WorldWideScience

Sample records for avianca plane crash

  1. Epidemiology of fatal and nonfatal injuries in the Avianca plane crash: Avianca Flight 052, January 25, 1990. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Barancik, J.I.; Kramer, C.F.; Thode, H.C. Jr.; Kahn, C.J. [Brookhaven National Lab., Upton, NY (United States); Greensher, J.; Schechter, S. [Nassau County Dept. of Health, Mineola, NY (United States)

    1992-11-01

    On January 25, 1990 Avianca Flight 052 crashed without a conflagration after running out of fuel; 73 persons died, 85 survived. Epidemiological, biostatistical, and related analytical methods were used for the analysis of decedent and survivor injury patterns and for the purpose of examining selected EMS and hospital issues-relative to disaster planning and incident management and response. Medical examiner and hospital records for all decedents and survivors were identified, abstracted, and coded using the International Classification of Diseases with Clinical Modifications, 9th Edition (ICD 9-CM) to determine the nature of injuries and comorbid conditions. Injury severity values were determined using the 1985 Abbreviated Injury Scale with Epidemiologic Modifications (AIS 85-EM).

  2. Suicide plane crash against nuclear power plants

    International Nuclear Information System (INIS)

    Cea (French atomic energy commission) and EDF (Electricity of France) are reassessing their safety standards concerning suicide plane attacks against nuclear facilities. The general idea is to study the non-linear behaviour of reinforced concrete in case of mechanical impact. American studies carried out in 1988 show that a F-14 phantom crashing into a 3,6 meter thick wall at a speed of 774 km/h penetrates only the first 5 cm of the wall. More recent studies performed in Germany and based on computerized simulations show that the reactor containment can sustain impacts from a F15 plane or even from a 747-Boeing but contiguous buildings like the one which houses spent fuels might be more easily damaged because of their metal roofing. (A.C.)

  3. Pediatric critical care social work: interventions with a special plane crash survivor.

    Science.gov (United States)

    Sefansky, S

    1990-08-01

    This article reviews the areas of social work practice that were necessary in the author's work with the family of the survivor of the Northwest Airlines Flight 255 plane crash in August 1987. Crisis intervention theory and family-centered social work practice are discussed as they relate to this unique situation. The areas of practice are broken into tasks for review and include tasks related to the institution, such as coordination with a variety of medical center departments, and tasks related to the family, such as identification, lodging, and privacy. The effects of the media on the staff and the institution and personal reactions to the involvement also are discussed. PMID:2401439

  4. The "flying" bile duct: avulsion of the common bile duct in a plane crash survivor.

    LENUS (Irish Health Repository)

    Mohan, H

    2012-02-01

    Blunt trauma is an unusual cause of extrahepatic bile duct injury. This is a case of a 51-year-old gentleman who sustained a significant seatbelt injury in a plane crash. Laparotomy, performed due to persistent abdominal pain, revealed that the common bile duct (CBD) was completely avulsed from the duodenum. Following insertion of drains and transfer to a hepatobiliary centre, the devascularised CBD was excised and replaced with a roux-en-y hepaticojejunostomy. Necrotic tissue was debrided from the pancreatic head. A persistent bile leak developed from the sub-hepatic drain. Repeat laparotomy revealed a bile leak from small ducts on the liver surface. Ligation of the ducts and bioglue sealing of the area were successfully performed. Subsequent to this a pancreatic fistula developed from the main pancreatic duct, which has since resolved. This unusual case illustrates the need for prompt recognition and early repair to optimise outcomes in traumatic CBD injury.

  5. A Story of a Crashed Plane in US-Mexican border

    Science.gov (United States)

    Bermudez, Luis; Hobona, Gobe; Vretanos, Peter; Peterson, Perry

    2013-04-01

    A plane has crashed on the US-Mexican border. The search and rescue command center planner needs to find information about the crash site, a mountain, nearby mountains for the establishment of a communications tower, as well as ranches for setting up a local incident center. Events like this one occur all over the world and exchanging information seamlessly is key to save lives and prevent further disasters. This abstract describes an interoperability testbed that applied this scenario using technologies based on Open Geospatial Consortium (OGC) standards. The OGC, which has about 500 members, serves as a global forum for the collaboration of developers and users of spatial data products and services, and to advance the development of international standards for geospatial interoperability. The OGC Interoperability Program conducts international interoperability testbeds, such as the OGC Web Services Phase 9 (OWS-9), that encourages rapid development, testing, validation, demonstration and adoption of open, consensus based standards and best practices. The Cross-Community Interoperability (CCI) thread in OWS-9 advanced the Web Feature Service for Gazetteers (WFS-G) by providing a Single Point of Entry Global Gazetteer (SPEGG), where a user can submit a single query and access global geographic names data across multiple Federal names databases. Currently users must make two queries with differing input parameters against two separate databases to obtain authoritative cross border geographic names data. The gazetteers in this scenario included: GNIS and GNS. GNIS or Geographic Names Information System is managed by USGS. It was first developed in 1964 and contains information about domestic and Antarctic names. GNS or GeoNET Names Server provides the Geographic Names Data Base (GNDB) and it is managed by National Geospatial Intelligence Agency (NGA). GNS has been in service since 1994, and serves names for areas outside the United States and its dependent areas, as

  6. Airplane crash

    International Nuclear Information System (INIS)

    In May, 1974, a severe airplane crash occurred near Springfield, llinois; the crew of three and a courier were killed. The plane was carrying a large container of controlled water with a slight amount of 60Co. A survey of the crash site by Air Force detectives and the radiological assistance team from Wright--Patterson Air Force Base indicated no radioactivity. Experiences of the incident were used to develop guidelines for future emergency preparedness

  7. The libidinal cocoon: a nurturing retreat for the families of plane crash victims.

    Science.gov (United States)

    Black, J W

    1987-12-01

    In 1985 the families of 137 passengers killed when a Delta Airlines jet crashed at Dallas-Fort Worth International Airport stayed in a secluded hotel while waiting for the victims' bodies to be retrieved and identified. In this protected environment, which the author calls the "libidinal cocoon," the families received intensive nurturing from the author, a Dallas psychiatrist; a team of Red Cross nurses; hotel staff; airline representatives; clergy; and each other. The supportive environment allowed the families to regress safely and to satisfy the basic yearning, intensified in times of personal loss, for an idealized caretaker who will meet all one's needs. The author believes this kind of intervention may be useful in future disasters with massive casualties. PMID:3692459

  8. FOG RISKS IN AVIATION. CASE STUDY: PLANE CRASH AT SMOLENSK (RUSSIA ON 10.04.2010

    Directory of Open Access Journals (Sweden)

    ŞCHIOPU COSMIN-LIVIU

    2013-03-01

    Full Text Available Fog, irrespective of its forms, has a negative impact on all aviation activities. Fog severely diminishes visibility, sometimes to such an extent that landing may become impossible. Fog is a serious weather threat and hazard in aviation and may produce deadly events. One such unfortunate event took place at Smolensk (Russia, on 10.04.2010, when the presidential aircraft, which was transporting Poland’s President, together with an official delegation, to commemorate 70 years from the Katyn massacre, simply crashed down close to the Smolensk North military aerodrome, at local hour 10:41:07.The present study actually makes an inventory of the extremely hazardous flying conditions, by thoroughly analyzing the weather reports and data, as well as visual and synoptic messages or official elements and information from that very day. All these materials show that the airdrome of destination was under the influence of a very active anti-cyclonic ridge, which accounted for very poor meteorological conditions. On such severe weather, the flight was doomed since greatly reduced visibility due to dense fog made landmarks orientation almost impossible and, furthermore, created false perceptions which led to fatal misjudgements and errors.

  9. Crash Under Investigation

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The cause of a fatal cargo plane accident in Shanghai is still unknown The flight data recorder of the Zimbabwean cargo plane that crashed on November 28 at Shanghai Pudong International Airport has been found near the crash scene,local aviation control authorities said.

  10. Icing – A Risk Factor in Aviation.Case Study: the Plane Crash in the Apuseni Mountains (Romania on 20.01.2014.

    Directory of Open Access Journals (Sweden)

    Şchiopu Cosmin-Liviu

    2015-05-01

    Full Text Available Icing - a risk factor in aviation. Case study: The plane crash in the Apuseni Mountains (Romania on 20.01.2014. Icing is a potentially harmful weather phenomenon for flight safety. Icing, irrespective of its forms, has a negative impact on all aviation activities since it severely impedes the aerodynamic properties of an aircraft, sometimes to such an extent that flying and landing may become impossible. Icing is a serious weather threat to aviation and may ultimately lead to deadly events. One such unfortunate event took place in the Western (Apuseni Mountains on the 20.01.2014, when an aircraft which was transporting a medical team on a humanitarian mission, simply crashed down in the area of the Western (Apuseni Mountains, at around 4:00 pm local time. The present study actually makes an inventory of the extremely hazardous flying conditions, by thoroughly analyzing the weather reports and data, as well as visual and synoptic messages or official elements and information from that very day. All these materials show that the flight route and the airdrome of destination were under the influence of a front which accounted for very poor meteorological conditions. On such bad weather, the flight was practically doomed to failure since low snow and sleet-bearing clouds were hanging down over the mountaintops. Flying straight through these clouds made any landmarks impossible to be seen and, furthermore, lack of orientation created false perceptions which led to fatal misjudgements and errors.

  11. Internationalization strategies of a Multilatina in the service sector: Avianca-Taca holdings S.A. case study

    Directory of Open Access Journals (Sweden)

    Carolina Franco-Arroyave

    2014-12-01

    Full Text Available This paper explores how existing internationalization theories can be applied to a Multilatina in the service sector, using the case of Avianca-Taca Holdings S.A. as an example. This paper introduces the company by analyzing the context in which it grew, starting with the service sector in Colombia, which is its country of origin. This paper also analyzes the international and domestic air transportation industry alongside the history of Avianca-Taca Holdings S.A. It describes in detail the internationalization program undertaken by the company and analyzes it based on three existing theories that may explain why such choices were made instead of others available. This paper explores different applications of these traditional theories. By this token, it concludes that, rather than using a brand new theory and aspiring to cover a large array of services, it is wiser to make decisions with a more comprehensive scope and use existing theories to adapt an efficient internationalization strategy to a particular context, region or country.

  12. Investigation of a fatal airplane crash: autopsy, computed tomography, and injury pattern analysis used to determine who was steering the plane at time of accident. A case report

    DEFF Research Database (Denmark)

    Høyer, Christian Bjerre; Nielsen, Trine Skov; Nagel, Lise Loft;

    2012-01-01

    A fatal accident is reported in which a small single-engine light airplane crashed. The airplane carried two persons in the front seats, both of whom possessed valid pilot certificates. Both victims were subject to autopsy, including post-mortem computed tomography scanning (PMCT) prior to the...... autopsy. The autopsies showed massive destruction to the bodies of the two victims but did not identify any signs of acute or chronic medical conditions that could explain loss of control of the airplane. PMCT, histological examination, and forensic chemical analysis also failed to identify an explanation...... for the crash. A detailed review of an airplane identical to the crashed airplane was performed in collaboration with the Danish Accident Investigation Board and the Danish National Police, National Centre of Forensic Services. The injuries were described using the abbreviated injury scale, the injury...

  13. Rail crash demonstration scenarios

    International Nuclear Information System (INIS)

    The paper describes the manner in which the rail crash scenario was selected for public demonstration. A simplified risk assessment led to the short listing of three contender scenarios involving a drop from a high level, a crash into an abutment and the crash of a train into a stationary flask. Predictive work led to the final selection of the train crash. (author)

  14. AP statistics crash course

    CERN Document Server

    D'Alessio, Michael

    2012-01-01

    AP Statistics Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP Statistics Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP Statistics course description outline and actual Advanced Placement test questions. It covers only the information tested on the exam, so you can make the most of your valuable study time. Our easy-to-read format covers: exploring da

  15. Allegheny County Crash Data

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Allegheny County from 2004 to 2015. Fields include injury severity,...

  16. Bubbles and market crashes

    CERN Document Server

    Youssefmir, M; Hogg, T; Youssefmir, Michael; Huberman, Bernardo; Hogg, Tad

    1994-01-01

    We present a dynamical theory of asset price bubbles that exhibits the appearance of bubbles and their subsequent crashes. We show that when speculative trends dominate over fundamental beliefs, bubbles form, leading to the growth of asset prices away from their fundamental value. This growth makes the system increasingly susceptible to any exogenous shock, thus eventually precipitating a crash. We also present computer experiments which in their aggregate behavior confirm the predictions of the theory.

  17. Currencies, Crises, and Crashes

    OpenAIRE

    Peter Kenen

    2002-01-01

    The emerging-market crises of the 1990s were characterized by crashes in exchange rates, credit flows, and output, and the currency crashes caused the other two. Because local banks and firms had large foreign-currency debts, the sharp depreciations of their countries' currencies had huge balance-sheet effects that led to an implosion of domestic credit flows, causing sharp falls in investment and output. It is wrong to blame the IMF for these calamitous outcomes. Nevertheless, the strategy a...

  18. Forensic odontological observations in the victims of DANA air crash

    OpenAIRE

    Obafunwa, John Oladapo; Ogunbanjo, Victor Olabode; Ogunbanjo, Ogunbiyi Babatunde; Soyemi, Sunday Sokunle; Faduyile, Francis Adedayo

    2015-01-01

    Introduction Forensic odontology or forensic dentistry is that aspect of forensic science that uses the application of dental science for the identification of unknown human remains and bite marks. Deaths resulting from mass disasters such as plane crash or fire incidence have always been given mass burial in Nigeria. This was obviously due to the fact that Forensic Pathologists whose roles involve disaster victim identification were not available at that time. However, in the DANA air crash ...

  19. Critical market crashes

    Science.gov (United States)

    Sornette, D.

    2003-04-01

    This review presents a general theory of financial crashes and of stock market instabilities that his co-workers and the author have developed over the past seven years. We start by discussing the limitation of standard analyses for characterizing how crashes are special. The study of the frequency distribution of drawdowns, or runs of successive losses shows that large financial crashes are “outliers”: they form a class of their own as can be seen from their statistical signatures. If large financial crashes are “outliers”, they are special and thus require a special explanation, a specific model, a theory of their own. In addition, their special properties may perhaps be used for their prediction. The main mechanisms leading to positive feedbacks, i.e., self-reinforcement, such as imitative behavior and herding between investors are reviewed with many references provided to the relevant literature outside the narrow confine of Physics. Positive feedbacks provide the fuel for the development of speculative bubbles, preparing the instability for a major crash. We demonstrate several detailed mathematical models of speculative bubbles and crashes. A first model posits that the crash hazard drives the market price. The crash hazard may sky-rocket at some times due to the collective behavior of “noise traders”, those who act on little information, even if they think they “know”. A second version inverses the logic and posits that prices drive the crash hazard. Prices may skyrocket at some times again due to the speculative or imitative behavior of investors. According the rational expectation model, this entails automatically a corresponding increase of the probability for a crash. We also review two other models including the competition between imitation and contrarian behavior and between value investors and technical analysts. The most important message is the discovery of robust and universal signatures of the approach to crashes. These precursory

  20. Braking news: link between crash severity and crash avoidance maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    This study focused on the link between crash severity and crash avoidance maneuvers. Various emergency lateral and speed control maneuvers were considered in response to different critical events that made the crash imminent. Partial proportional odds models that allowed for changes in effects...... across severity levels were estimated to accommodate the ordered-response nature of severity. The sample used for estimation consisted of data for single-vehicle crashes extracted from the General Estimates System crash database for the period from 2005 to 2009. Results showed the correlation between...... crash avoidance maneuvers and crash severity, with differences emerging for different critical events. Moreover, results showed two trends:(a) most drivers failed to act when facing critical events and (b) drivers rarely performed crash avoidance maneuvers that were correlated with a higher probability...

  1. Estimating likelihood of future crashes for crash-prone drivers

    Directory of Open Access Journals (Sweden)

    Subasish Das

    2015-06-01

    Full Text Available At-fault crash-prone drivers are usually considered as the high risk group for possible future incidents or crashes. In Louisiana, 34% of crashes are repeatedly committed by the at-fault crash-prone drivers who represent only 5% of the total licensed drivers in the state. This research has conducted an exploratory data analysis based on the driver faultiness and proneness. The objective of this study is to develop a crash prediction model to estimate the likelihood of future crashes for the at-fault drivers. The logistic regression method is used by employing eight years' traffic crash data (2004–2011 in Louisiana. Crash predictors such as the driver's crash involvement, crash and road characteristics, human factors, collision type, and environmental factors are considered in the model. The at-fault and not-at-fault status of the crashes are used as the response variable. The developed model has identified a few important variables, and is used to correctly classify at-fault crashes up to 62.40% with a specificity of 77.25%. This model can identify as many as 62.40% of the crash incidence of at-fault drivers in the upcoming year. Traffic agencies can use the model for monitoring the performance of an at-fault crash-prone drivers and making roadway improvements meant to reduce crash proneness. From the findings, it is recommended that crash-prone drivers should be targeted for special safety programs regularly through education and regulations.

  2. Road crash costs.

    OpenAIRE

    2010-01-01

    Road crashes result in all kinds of social costs, such as medical costs, production loss, human losses, property damage, settlement costs and costs due to congestion. Studies into road crash costs and their trends are carried out quite regularly. In 2009, the costs amounted to € 12.5 billion, or 2.2% of the Gross Domestic Product (GDP). Insight into these costs is used for policy preparation and evaluation, and makes it possible to compare them with costs in other areas. Another important app...

  3. The Crash of '87

    OpenAIRE

    Freeman, Alan

    1988-01-01

    This article was published in a Capital and Class symposium on the 1987 crash. Its analysis retains its full force in 2009. It compared the 1987 and the 1929 crash, and explored the historical similarities between the long US postwar decline and the UK’s, from the mid-nineteenth century. It situated both in a rigorous value-theoretic framework rooted in Marx’s concept of superprofit. It was the author’s first such published attempt. It combined, critically, Kondratieff’s account of long w...

  4. Time-Varying Crash Risk

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Feunoua, Bruno; Jeon, Yoontae;

    We estimate a continuous-time model with stochastic volatility and dynamic crash probability for the S&P 500 index and find that market illiquidity dominates other factors in explaining the stock market crash risk. While the crash probability is time-varying, its dynamic depends only weakly on...

  5. Estudio de factibilidad para formar idóneamente técnicos línea de aviones aprovechando la capacidad ociosa disponible del Centro de Entrenamiento Técnico de Avianca

    OpenAIRE

    Castillo Waltero, Monica Paola; Marín Maya, María Cecilia

    2013-01-01

    Avianca es una aerolínea colombiana con más de noventa años en la industria del transporte aéreo de pasajeros -- Cuenta además con un aproximado de mil personas capacitadas exclusivamente para la atención técnica de las aeronaves y realiza esta labor en el Centro de Entrenamiento Técnico ubicado en la ciudad de Bogotá -- Los técnicos línea de aviones son personas que realizaron estudios básicos de técnicos en instituciones técnicas y tecnológicas en su mayoría colombianas y posteriorm...

  6. Blind spot crashes.

    NARCIS (Netherlands)

    2009-01-01

    Crashes involving lorries turning right and cyclists going straight ahead usually have very serious consequences for the cyclist. The cyclist, who has right of way, is often overlooked by the lorry driver. For his part, the cyclist is often unaware that the lorry driver has not seen him or that the

  7. Advances in Crash Response

    Centers for Disease Control (CDC) Podcasts

    2009-06-29

    In this podcast, Dr. Richard C. Hunt, Director of CDC's Division of Injury Response, provides an overview on the benefits of using an Advanced Automatic Collision Notification system, or AACN, to help with emergency triage of people injured in vehicle crashes.  Created: 6/29/2009 by National Center for Injury Prevention and Control (NCIPC), Division of Injury Response (DIR).   Date Released: 6/29/2009.

  8. Crashes and Collateralized Lending

    OpenAIRE

    Jakub W. Jurek; Erik Stafford

    2011-01-01

    This paper develops a parsimonious static model for characterizing financing terms in collateralized lending markets. We characterize the systematic risk exposures for a variety of securities and develop a simple indifference-pricing framework to value the systematic crash risk exposure of the collateral. We then apply Modigliani and Miller's (1958) Proposition Two (MM) to split the cost of bearing this risk between the borrower and lender, resulting in a schedule of haircuts and financing ra...

  9. AP physics B crash course

    CERN Document Server

    Howell, Rebecca

    2012-01-01

    AP Physics B Crash Course - Get a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. Our AP Physics B Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know The Crash Course is based on an in-depth analysis of the AP Physics B course description outline and actual AP test questions. It covers only the information tested on the exam, so you can make the most of your valuable study time. Our easy-to-read format covers: mechanics, kinetic theory, t

  10. Crash course in readers' advisory

    CERN Document Server

    Orr, Cynthia

    2014-01-01

    One of the key services librarians provide is helping readers find books they'll enjoy. This ""crash course"" will furnish you with the basic, practical information you need to excel at readers' advisory (RA) for adults and teens.

  11. Building concepts against airplane crash

    International Nuclear Information System (INIS)

    In Germany safety related buildings of nuclear facilities as well as their equipment are to be designed against airplane crash. While the safety of the structure itself can always be guaranteed by structural means, the induced vibrations may cause severe problems for the equipment. Considerable effort was expended in recent years to comprehend the load case airplane crash in a more exact manner and to evaluate reasonable floor response spectra. Besides this analytical effort, investigations are cited to minimize the induced vibrations by new structural concepts. The present paper gives a survey concerning the development of structural concepts, culminating in the double shell structures that are state of the art today. Then the idea of spring supports, as it is known for the aseismic foundation of buildings, is further developed to a new spring concept which reduces the induced vibrations in an optimum way in the load case airplane crash and which additionally isolates earthquake vibrations. (orig.)

  12. Weather Conditions, Weather Information and Car Crashes

    OpenAIRE

    Adriaan Perrels; Athanasios Votsis; Väinö Nurmi; Karoliina Pilli-Sihvola

    2015-01-01

    Road traffic safety is the result of a complex interaction of factors, and causes behind road vehicle crashes require different measures to reduce their impacts. This study assesses how strongly the variation in daily winter crash rates associates with weather conditions in Finland. This is done by illustrating trends and spatiotemporal variation in the crash rates, by showing how a GIS application can evidence the association between temporary rises in regional crash rates and the occurrence...

  13. Distracted Driving Raises Crash Risk

    Science.gov (United States)

    ... a Seriously Ill Child Featured Website: NIDA for Teens Past Issues Most Viewed February 2014 Print RSS Find us on Facebook External link, please review our exit disclaimer . Subscribe Distracted Driving Raises Crash Risk Video technology and in-vehicle sensors showed that distracted driving, ...

  14. Market Crashes without External Shocks

    OpenAIRE

    Sergiu Hart; Yair Tauman

    2004-01-01

    It is shown here that market crashes and bubbles can arise without external shocks. Sudden changes in behavior coming after a long period of stationarity may be the result of endogenous information processing. Except for the daily observation of the market, there is no new information, no communication and no coordination among the participants.

  15. Knowledge crash and knowledge management

    OpenAIRE

    Ermine, Jean-Louis

    2010-01-01

    This article, by including the problem of “Knowledge Crash” in the more general framework of “Knowledge Management”, enlarges the concepts of knowledge, generation and knowledge transfer. It proposes a global approach, starting from a strategic analysis of a knowledge capital and ending in the implementation of socio-technical devices for inter-generational knowledge transfer.

  16. Braking News: the Link between Crash Severity and Crash Avoidance Maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    This study focuses on the linkage between crash severity and crash avoidance maneuvers. Various emergency lateral and speed control maneuvers are considered in response to different critical events that made the crash imminent. Partial proportional odds models are estimated to accommodate the...... ordered-response nature of severity while allowing for changes in effects across severity levels. The data sample for estimation consists of single-vehicle crashes extracted from the General Estimates System (GES) crash database for the period 2005-2009. Results show the correlation between crash...... avoidance maneuvers and crash severity, with differences emerging for different critical events. Moreover, results show two trends: (i) most drivers fail to act when facing critical events, and (ii) drivers rarely perform crash avoidance maneuvers that are correlated with higher probability of lower crash...

  17. Crash energy absorption of two-segment crash box with holes under frontal load

    Science.gov (United States)

    Choiron, Moch. Agus; Sudjito, Hidayati, Nafisah Arina

    2016-03-01

    Crash box is one of the passive safety components which designed as an impact energy absorber during collision. Crash box designs have been developed in order to obtain the optimum crashworthiness performance. Circular cross section was first investigated with one segment design, it rather influenced by its length which is being sensitive to the buckling occurrence. In this study, the two-segment crash box design with additional holes is investigated and deformation behavior and crash energy absorption are observed. The crash box modelling is performed by finite element analysis. The crash test components were impactor, crash box, and fixed rigid base. Impactor and the fixed base material are modelled as a rigid, and crash box material as bilinear isotropic hardening. Crash box length of 100 mm and frontal crash velocity of 16 km/jam are selected. Crash box material of Aluminum Alloy is used. Based on simulation results, it can be shown that holes configuration with 2 holes and ¾ length locations have the largest crash energy absorption. This condition associated with deformation pattern, this crash box model produces axisymmetric mode than other models.

  18. Cost of Physical Vehicle Crash Testing

    OpenAIRE

    Baguley, Paul; Roy, Rajkumar; James W. Watson

    2008-01-01

    The automotive safety-testing environment currently deploys virtual methods and physical crash testing for new product development and validation in safety testing legislation. Cost benefit analysis of crash testing is considered here by estimating the cost of physical crash testing. This has been achieved via the compilation of detailed process maps and AS-IS analyses of the current physical testing procedures. This leads on to detailed work and cost breakdown structures used in the comparat...

  19. Abdominal Injury Patterns in Real Frontal Crashes: Influence of Crash Conditions, Occupant Seat and Restraint Systems

    OpenAIRE

    Lamielle, S.; CUNY,S; Foret-Bruno, JY.; Petit, P.; VEZIN,P; Verriest, JP.; Guillemot, H.

    2006-01-01

    An in-depth study was conducted through the analysis of medical reports and crash data from real world accidents. The objective was to investigate the abdominal injury patterns among car occupants in frontal crashes. The influence of the type of restraint system, the occupant seat, the age and the crash severity was investigated. The results indicate that the risk of abdominal AIS 3+ injuries increased with crash severity and decreased with the introduction of belt retractors. Rear belted pas...

  20. Motorcycle-related spinal injury: crash characteristics.

    Science.gov (United States)

    Zulkipli, Zarir Hafiz; Abdul Rahmat, Abdul Manap; Mohd Faudzi, Siti Atiqah; Paiman, Noor Faradila; Wong, Shaw Voon; Hassan, Ahamedali

    2012-11-01

    This study presents an analysis of crash characteristics of motorcyclists who sustained spinal injuries in motorcycle crashes. The aim of the study is to identify the salient crash characteristics that would help explain spinal injury risks for motorcyclists. Data were retrospectively collected from police case reports that were archived at MIROS from year 2005 to 2007. The data were categorized into two subcategories; the first group was motorcycle crashes with spinal injury (case) and the second group was motorcycle crashes without spinal injury (control). A total of 363 motorcyclists with spinal injury and 873 motorcyclists without spinal injury were identified and analyzed. Descriptive analysis and multivariate analysis were performed in order to determine the odds of each characteristic in contributing to spinal injury. Single vehicle crash, collision with fixed objects and crash configuration were found to have significant influence on motorcyclists in sustaining spinal injury (p<0.05). Although relatively few than other impact configurations, the rear-end impacted motorcyclist shows the highest risk of spinal injury. Helmets have helped to reduce head injury but they did not seem to offer corresponding protection for the spine in the study. With a growing number of young motorcyclists, further efforts are needed to find effective measures to help reduce the crash incidents and severity of spinal injury. In sum, the study provides some insights on some vital crash characteristics associated with spinal injury that can be further investigated to determine the appropriate counter-measures and prevention strategies to reduce spinal injury. PMID:23036400

  1. AP calculus AB & BC crash course

    CERN Document Server

    Rosebush, J

    2012-01-01

    AP Calculus AB & BC Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP Calculus AB & BC Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP Calculus AB & BC course description outline and actual AP test questions. It covers only the information tested on the exams, so you can make the most of your valuable study time. Written by experienced math teachers, our

  2. AP English language & composition crash course

    CERN Document Server

    Hogue, Dawn

    2012-01-01

    AP English Language & Composition Crash Course - Gets You a Higher Advanced Placement Score in Less Time Crash Course is perfect for the time-crunched student, the last-minute studier, or anyone who wants a refresher on the subject. AP English Language & Composition Crash Course gives you: Targeted, Focused Review - Study Only What You Need to Know Crash Course is based on an in-depth analysis of the AP English Language & Composition course description outline and actual Advanced Placement test questions. It covers only the information tested on the exam, so you can make the most of your valua

  3. Database improvements for motor vehicle/bicycle crash analysis

    OpenAIRE

    Lusk, Anne C; Asgarzadeh, Morteza; Farvid, Maryam S

    2015-01-01

    Background: Bicycling is healthy but needs to be safer for more to bike. Police crash templates are designed for reporting crashes between motor vehicles, but not between vehicles/bicycles. If written/drawn bicycle-crash-scene details exist, these are not entered into spreadsheets. Objective: To assess which bicycle-crash-scene data might be added to spreadsheets for analysis. Methods: Police crash templates from 50 states were analysed. Reports for 3350 motor vehicle/bicycle crashes (2011) w...

  4. Property Damage Crash Equivalency Factors for Solving the Crash Frequency-Severity Dilemma: Case Study on South Korean Rural Roads

    OpenAIRE

    Oh, Jutaek; Washington, Simon; Lee, Dongmin

    2010-01-01

    Safety interventions (e.g. median barriers, photo enforcement) and road features (e.g. median type and width) can influence crash severities, crash frequencies, or both. Both dimensions—crash frequency and crash severity—are needed to obtain a full accounting of road safety. Extensive literature and common sense both dictate that all crashes are not ‘created’ equal—with fatalities costing society more than 1000 times the cost of property damage only crashes. Despite this glowing disparity, th...

  5. Crash Impact Demonstration. (pt 6/10)

    Science.gov (United States)

    1984-01-01

    This clip: Cockpit interior. Showing the pilot during impact, view forward. With narration. Background: On December 1st, 1984, a remote controlled 4 engined transport jet took off from Edwards AFB, CA and crashed into a barren patch of nearby desert. This Controlled Impact Demonstration was a joint R&D program by the FAA and NASA. The FAA designed the C.I.D. to underscore results of exhaustive research in two areas of aircraft safety: improved crash protection and reduced post-crash fire hazards.Despite the fact the crash did not go exactly as designed C.I.D.did achieve its primary objectives.The analysis of C.I.D. data continues. The CID's crash wothiness tests were as important to the FAA as the fire safety tests. The crash protection objectives were: 1st: To obtain data on impact forces and their transmission thru the structure to the seats and occupants. 2nd: To evaluate the performance of existing and advanced energy absorbing seats. 3rd :To compare tests used to predict structural behaviour with an actual crash. AMK (anti-misting kerosene) fuel was employed in the test. The FAA has examined AMK's potential for protecting commercial transports from ignition of misted fuels. All research indicated that AMK would be effective in preventing this problem. The C.I.D. was an opportunity to use AMK in a realistic, impact-survivable crash.

  6. Crash Impact Demonstration. (pt 7/10)

    Science.gov (United States)

    1984-01-01

    This clip: Montage of several different views thru the duration of impact. With narration. Background: On December 1st, 1984, a remote controlled 4 engined transport jet took off from Edwards AFB, CA and crashed into a barren patch of nearby desert. This Controlled Impact Demonstration was a joint R&D program by the FAA and NASA. The FAA designed the C.I.D. to underscore results of exhaustive research in two areas of aircraft safety: improved crash protection and reduced post-crash fire hazards.Despite the fact the crash did not go exactly as designed C.I.D.did achieve its primary objectives.The analysis of C.I.D. data continues. The CID's crash wothiness tests were as important to the FAA as the fire safety tests. The crash protection objectives were: 1st: To obtain data on impact forces and their transmission thru the structure to the seats and occupants. 2nd: To evaluate the performance of existing and advanced energy absorbing seats. 3rd :To compare tests used to predict structural behaviour with an actual crash. AMK (anti-misting kerosene) fuel was employed in the test. The FAA has examined AMK's potential for protecting commercial transports from ignition of misted fuels. All research indicated that AMK would be effective in preventing this problem. The C.I.D. was an opportunity to use AMK in a realistic, impact-survivable crash.

  7. Crash Impact Demonstration. (pt 3/10)

    Science.gov (United States)

    1984-01-01

    This clip: Extreme Long shot of impact showing the huge fireball surrounding the airplane. With narration. Background: On December 1st, 1984, a remote controlled 4 engined transport jet took off from Edwards AFB, CA and crashed into a barren patch of nearby desert. This Controlled Impact Demonstration was a joint R&D program by the FAA and NASA. The FAA designed the C.I.D. to underscore results of exhaustive research in two areas of aircraft safety: improved crash protection and reduced post-crash fire hazards.Despite the fact the crash did not go exactly as designed C.I.D.did achieve its primary objectives.The analysis of C.I.D. data continues. The CID's crash wothiness tests were as important to the FAA as the fire safety tests. The crash protection objectives were: 1st: To obtain data on impact forces and their transmission thru the structure to the seats and occupants. 2nd: To evaluate the performance of existing and advanced energy absorbing seats. 3rd :To compare tests used to predict structural behaviour with an actual crash. AMK (anti-misting kerosene) fuel was employed in the test. The FAA has examined AMK's potential for protecting commercial transports from ignition of misted fuels. All research indicated that AMK would be effective in preventing this problem. The C.I.D. was an opportunity to use AMK in a realistic, impact-survivable crash.

  8. Seat Design for Crash Worthiness

    Science.gov (United States)

    Pinkel, I Irving; Rosenberg, Edmund G

    1957-01-01

    A study of many crash deceleration records suggested a simplified model of a crash deceleration pulse, which incorporates the essential properties of the pulse. The model pulse is considered to be composed of a base pulse on which are superimposed one or more secondary pulses of shorter duration. The results of a mathematical analysis of the seat-passenger deceleration in response to the airplane deceleration pulse are provided. On the basis of this information, presented as working charts, the maximum deceleration loads experienced by the seat and passenger in response to the airplane deceleration pulse can be computed. This maximum seat-passenger deceleration is found to depend on the natural frequency of the seat containing the passenger, considered as a mass-spring system. A method is presented that shows how to arrive at a combination of seat strength, natural frequency, and ability to absorb energy in deformation beyond the elastic limit that will allow the seat to serve without failure during an airplane deceleration pulse taken as the design requirement.

  9. Weather Conditions, Weather Information and Car Crashes

    Directory of Open Access Journals (Sweden)

    Adriaan Perrels

    2015-11-01

    Full Text Available Road traffic safety is the result of a complex interaction of factors, and causes behind road vehicle crashes require different measures to reduce their impacts. This study assesses how strongly the variation in daily winter crash rates associates with weather conditions in Finland. This is done by illustrating trends and spatiotemporal variation in the crash rates, by showing how a GIS application can evidence the association between temporary rises in regional crash rates and the occurrence of bad weather, and with a regression model on crash rate sensitivity to adverse weather conditions. The analysis indicates that a base rate of crashes depending on non-weather factors exists, and some combinations of extreme weather conditions are able to substantially push up crash rates on days with bad weather. Some spatial causation factors, such as variation of geophysical characteristics causing systematic differences in the distributions of weather variables, exist. Yet, even in winter, non-spatial factors are normally more significant. GIS data can support optimal deployment of rescue services and enhance in-depth quantitative analysis by helping to identify the most appropriate spatial and temporal resolutions. However, the supportive role of GIS should not be inferred as existence of highly significant spatial causation.

  10. Post-crash fuel dispersal

    Energy Technology Data Exchange (ETDEWEB)

    Tieszen, S.R.

    1997-03-01

    This paper is a brief overview of work over the last several decades in understanding what occurs to jet fuel stored in aircraft fuel tanks on impact with the ground. Fuel dispersal is discussed in terms of the overall crash dynamics process and impact regimes are identified. In a generic sense, the types of flow regimes which can occur are identified and general descriptions of the processes are given. Examples of engineering level tools, both computational and experimental, which have applicability to analyzing the complex environments are presented. Finally, risk based decision is discussed as a quick means of identifying requirements for development of preventative or mitigation strategies, such as further work on the development of an anti-misting agent.

  11. 49 CFR 238.403 - Crash energy management.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Crash energy management. 238.403 Section 238.403... Equipment § 238.403 Crash energy management. (a) Each power car and trailer car shall be designed with a crash energy management system to dissipate kinetic energy during a collision. The crash...

  12. Factors Contributing to Crashes among Young Drivers

    Directory of Open Access Journals (Sweden)

    Lyndel J. Bates

    2014-08-01

    Full Text Available Young drivers are the group of drivers most likely to crash. There are a number of factors that contribute to the high crash risk experienced by these drivers. While some of these factors are intrinsic to the young driver, such as their age, gender or driving skill, others relate to social factors and when and how often they drive. This article reviews the factors that affect the risk of young drivers crashing to enable a fuller understanding of why this risk is so high in order to assist in developing effective countermeasures.

  13. Injury Differences Between Small and Large Overlap Frontal Crashes

    OpenAIRE

    Hallman, Jason J.; Yoganandan, Narayan; Pintar, Frank A.; Maiman, Dennis J.

    2011-01-01

    Because small overlap impacts have recently emerged as a crash mode posing great injury risk to occupants, a detailed analysis of US crash data was conducted using the NASS/CDS and CIREN databases. Frontal crashes were subcategorized into small overlap impact (SOI) and large overlap impact (LOI) using crash and crush characteristics from the datasets. Injuries to head, spine, chest, hip and pelvis, and lower extremities were parsed and compared between crash types. MAIS 3+ occupants in NASS/C...

  14. Amplification and Asymmetry in Crashes and Frenzies

    OpenAIRE

    Han N. Ozsoylev

    2005-01-01

    We often observe disproportionate reactions to tangible information in large stock price movements. Moreover these movements feature an asymmetry: the number of crashes is more than that of frenzies in the S&P 500 index. This paper offers an explanation for these two characteristics of large movements in which hedging (portfolio insurance) causes amplified price reactions to news and liquidity shocks as well as an asymmetry biased towards crashes. Risk aversion of traders is shown to be essen...

  15. Modelling the Crash Response of Composite Structures

    OpenAIRE

    Johnson, A.; Kohlgrüber, D.

    1997-01-01

    The paper describes recent progress on the materials modelling and numerical simulation of the dynamic crash response of fibre reinforced composite structures. The work is based on the application of explicit finite element analysis codes to composite aircraft structures and structural elements under low velocity impact conditions (up to 15 m/s). Structures studied are designed to absorb crash energy and reduce seat deceleration pulses in aircraft subfloor structures, and consist of an aircra...

  16. Marijuana Use and Motor Vehicle Crashes

    OpenAIRE

    Li, Mu-Chen; Brady, Joanne E.; DiMaggio, Charles J.; Lusardi, Arielle R.; Tzong, Keane Y.; Li, Guohua

    2011-01-01

    Since 1996, 16 states and the District of Columbia in the United States have enacted legislation to decriminalize marijuana for medical use. Although marijuana is the most commonly detected nonalcohol drug in drivers, its role in crash causation remains unsettled. To assess the association between marijuana use and crash risk, the authors performed a meta-analysis of 9 epidemiologic studies published in English in the past 2 decades identified through a systematic search of bibliographic data...

  17. Crash Recovery for Embedded Main Memory Database

    OpenAIRE

    Fang Ye; Shuang Wang; Yi-bing Li

    2012-01-01

    In the last years, the deployment of embedded real-time communication systems has increased dramatically. At the same time, the amount of data that needs to be managed by embedded real-time main memory databases is increasing, thus requiring an efficient data management. However, system crash will cause data loss in main memory, which will seriously affect the normal operation of the entire communication system. This paper introduces an algorithm of system crash recovery applied in main memor...

  18. Utilizing computed tomography scans for analysis of motorcycle helmets in real-world crashes - biomed 2011.

    Science.gov (United States)

    Loftis, Kathryn L; Moreno, Daniel P; Tan, Joshua; Gabler, Hampton C; Stitzel, Joel D

    2011-01-01

    In 2008, there were more than 5,000 motorcycle crash fatalities in the United States. Many states have motorcycle helmet laws that are meant to protect riders during a crash. After recruiting motorcycle occupants injured in crashes, a protocol was established to scan three different types of motorcycle helmets commonly worn (cap, ¾ shield, and full face shield) using a computed tomography (CT) scanner. The protocol developed was for a GE 64 slice PET/CT Discovery VCT scanner with axial images from anterior to posterior helmet acquired in helical mode. It had 512x512 resolution and the full face and ¾ face shield helmets were scanned with greater voxels in the axial plane compared to the skull cap helmets. New helmets were scanned as exemplary images for comparison with helmets involved in motorcycle crashes. After CT scans were gathered, three-dimensional reconstructions were made to visualize scratches and impacts to the exterior of the helmets. Initial work was also conducted in analyzing interior components, and a trend was seen in decreased thickness between the interior foam and shell with sides of the exterior helmet thought to have contacted roadside barriers or the ground during motorcycle crashes. These helmet analysis methods have been established, and will be used to investigate multiple motorcycle crashes in conjunction with occupant injuries and direct head impacts to improve helmet design and the understanding of head injuries. This work also establishes the basis for development of finite element models of three of the most common helmet types. PMID:21525626

  19. The risk of PTSD and depression after an airplane crash and its potential association with physical injury: A longitudinal study.

    Science.gov (United States)

    Gouweloos, Juul; Postma, Ingri L E; te Brake, Hans; Sijbrandij, Marit; Kleber, Rolf J; Goslings, J Carel

    2016-01-01

    In 2009, a commercial airplane crashed near Amsterdam. This longitudinal study aims to investigate (1) the proportion of survivors of the airplane crash showing a probable posttraumatic stress disorders (PTSD) or depressive disorder, and (2) whether symptoms of PTSD and depression were predicted by trauma characteristics. Identifying these trauma characteristics is crucial for early detection and treatment. Of the 121 adult survivors, 82 participated in this study 2 months after the crash and 76 participated 9 months after the crash. Risk for PTSD and depression was measured with the self-report instruments Trauma Screening Questionnaire and Patient Health Questionnaire-2. Trauma characteristics assessed were Injury Severity Score (ISS), hospitalisation, length of hospital stay, and seating position in the plane. Two months after the crash, 32 participants (of N=70, 46%) were at risk for PTSD and 28 (of N=80, 32%) were at risk for depression. Nine months after the crash, 35 participants (of N=75, 47%) were at risk for PTSD and 24 (of N=76, 35%) were at risk for depression. There was a moderate correlation between length of hospital stay and symptoms of PTSD and depression 9 months after the crash (r=.33 and r=.45, respectively). There were no differences in seating position between participants at high risk vs. participants at low risk for PTSD or depression. Mixed design ANOVAs showed also no association between the course of symptoms of PTSD and depression 2 and 9 months after the crash and ISS or hospitalisation. This suggests that health care providers need to be aware that survivors may be at risk for PTSD or depression, regardless of the objective severity of their physical injuries. PMID:26210753

  20. Property Damage Crash Equivalency Factors for Solving the Crash Frequency-Severity Dilemma: Case Study on South Korean Rural Roads

    OpenAIRE

    Oh, Jutaek; Washington, Simon; Lee, Dongmin

    2010-01-01

    Safety interventions (e.g. median barriers, photo enforcement) and road features (e.g. median type and width) can influence crash severities, crash frequencies, or both. Both dimensions—crash frequency and crash severity—are needed to obtain a full accounting of road safety. Extensive literature and common sense both dictate that all crashes are not ‘created’ equal—with fatalities costing society more than 1000 times the cost of property damage only crashes. Despite this glowing dis...

  1. Predicting crash risk and identifying crash precursors on Korean expressways using loop detector data.

    Science.gov (United States)

    Kwak, Ho-Chan; Kho, Seungyoung

    2016-03-01

    In order to improve traffic safety on expressways, it is important to develop proactive safety management strategies with consideration for segment types and traffic flow states because crash mechanisms have some differences by each condition. The primary objective of this study is to develop real-time crash risk prediction models for different segment types and traffic flow states on expressways. The mainline of expressways is divided into basic segment and ramp vicinity, and the traffic flow states are classified into uncongested and congested conditions. Also, Korean expressways have irregular intervals between loop detector stations. Therefore, we investigated on the effect and application of the detector stations at irregular intervals for the crash risk prediction on expressways. The most significant traffic variables were selected by conditional logistic regression analysis which could control confounding factors. Based on the selected traffic variables, separate models to predict crash risk were developed using genetic programming technique. The model estimation results showed that the traffic flow characteristics leading to crashes are differed by segment type and traffic flow state. Especially, the variables related to the intervals between detector stations had a significant influence on crash risk prediction under the uncongested condition. Finally, compared with the single model for all crashes and the logistic models used in previous studies, the proposed models showed higher prediction performance. The results of this study can be applied to develop more effective proactive safety management strategies for different segment types and traffic flow states on expressways with loop detector stations at irregular intervals. PMID:26710266

  2. A study to maximize the crash energy absorption efficiency within the limits of crash space

    International Nuclear Information System (INIS)

    The design of an engine room is important to protect the passenger from a crash impact by improving the absorption of the crash impact energy. The side member in the engine room absorbs most of the crash impact energy when the vehicle experiences a frontal crash. The side member is of two types: hat and 'U.' Analysis of the extent of energy absorption and the mechanism of the side member are necessary through a collapse mode in various load conditions. In this study, the design of experiments was used for evaluating the characteristics of the absorption of crash energy by side members through design variables. First, crash analysis was performed by experiment number extracted from the design of the experiment. Then, using the results of crash analysis, multiple regressions were conducted and sensitivity analysis performed for each design variable. Finally, the optimum design was developed for maximizing the absorption energy per unit weight considering various boundary conditions. In the present study, as a basic step for modeling the fatigue behavior of an extruded Al alloy cylinder, the fatigue crack growth data of the alloy was collected in two orientations. Microstructural analysis revealed that the material had recrystallized grains and clusters of constituent particles aligned in the direction of extrusion. Fatigue life of the samples revealed a shorter fatigue life representing a higher fatigue crack growth rate in the transverse direction

  3. Crash Recovery for Embedded Main Memory Database

    Directory of Open Access Journals (Sweden)

    Fang Ye

    2012-10-01

    Full Text Available In the last years, the deployment of embedded real-time communication systems has increased dramatically. At the same time, the amount of data that needs to be managed by embedded real-time main memory databases is increasing, thus requiring an efficient data management. However, system crash will cause data loss in main memory, which will seriously affect the normal operation of the entire communication system. This paper introduces an algorithm of system crash recovery applied in main memory database of embedded real-time communication system. This paper expatiates the software architecture of SDR base station, the cause of crash occurring, and proposes the flash recovery algorithm using for system recovery. A main memory database using this algorithm has been applied in a real communication system——multimode SDR base station communication system.

  4. Transportation Institute releases findings on driver behavior and crash factors

    OpenAIRE

    Box, Sherri

    2006-01-01

    Driver inattention is the leading factor in most crashes and near-crashes, according to a landmark research report released today by the National Highway Traffic Safety Administration (NHTSA) and the Virginia Tech Transportation Institute (VTTI).

  5. Gender and Age Differences among Teen Drivers in Fatal Crashes

    OpenAIRE

    Swedler, David I.; Bowman, Stephen M.; Baker, Susan P.

    2012-01-01

    To identify age and gender differences among teen drivers in fatal crashes, we analyzed FARS data for 14,026crashes during 2007–2009. Compared with female teenagers, crashes of male teenagers were significantly more likely to involve BACs of 0.08% or more (21% vs. 12%), speeding (38% vs. 25%), reckless driving (17% vs. 14%), night driving (41% vs. 36%) and felony crashes (hit-and-run, homicide, or manslaughter) (8% vs. 6%) (all χ2 p

  6. Identification of Car Passengers with RFID for Automatic Crash Notification

    OpenAIRE

    Ouyang, Dongfang

    2009-01-01

    Automatic Crash Notification is a system designed to be used in a crash situation. When a crash occurs, the intelligent system is activated and automatically sends select crash details to the appropriate Emergency Medical Service Center. These details can be the position of the vehicle and the likely severity of the damage. Using the information, the medical treatment resources demanded for the accident is assessed at Emergency Center. Accordingly, first-aid facilities are promptly and proper...

  7. Influence of Cannabis on Fatal Traffic Crash: A Detailed Analysis

    OpenAIRE

    VAN ELSLANDE, Pierre; FOURNIER, Jean-Yves; Jaffard, Magali

    2012-01-01

    The influence of cannabis on traffic crashes is a growing concern. Experimental studies provide ample evidences of cannabis influence on psychomotor and cognitive performances. Epidemiological works describe the excess crash risk that this substance causes. And yet, this psychotropic drug influence in causing crashes is still at the centre of many discussions. The present analysis consists in exploiting crash data in detail to obtain a more precise understanding of the failures that drivers a...

  8. Gasoline Prices and Their Relationship to Drunk-Driving Crashes

    OpenAIRE

    Guangqing Chi; Xuan Zhou; Timothy McClure; Paul Gilbert; Arthur Cosby; Li Zhang; Angela Robertson; David Levinson

    2010-01-01

    This study investigates the relationship between changing gasoline prices and drunk-driving crashes. Specifically, we examine the effects of gasoline prices on drunk-driving crashes in Mississippi by age, gender, and race from 2004Ð2008, a period experiencing great fluctuation in gasoline prices. An exploratory visualization by graphs shows that higher gasoline prices are generally associated with fewer drunk-driving crashes. Higher gasoline prices depress drunk- driving crashes among younger...

  9. Pre-crash system validation with PRESCAN and VEHIL

    NARCIS (Netherlands)

    Gietelink, O.J.; Verburg, D.J.; Labibes, K.; Oostendorp, A.F.

    2004-01-01

    This paper presents the tools for design and validation of Pre-Crash Systems: the software tool PRE-crash SCenario ANalyzer (PRESCAN) and the VEhicle-Hardware-In-the-Loop (VEHIL) facility. PRESCAN allows to investigate a pre-crash scenario in simulation. This scenario can then be compared with tests

  10. 14 CFR 29.952 - Fuel system crash resistance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel system crash resistance. 29.952... crash resistance. Unless other means acceptable to the Administrator are employed to minimize the hazard of fuel fires to occupants following an otherwise survivable impact (crash landing), the fuel...

  11. 49 CFR 563.10 - Crash test performance and survivability.

    Science.gov (United States)

    2010-10-01

    ... CFR 571.208, Occupant crash protection, must comply with the requirements in subpart (c) of this... 49 Transportation 6 2010-10-01 2010-10-01 false Crash test performance and survivability. 563.10... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EVENT DATA RECORDERS § 563.10 Crash...

  12. 14 CFR 27.952 - Fuel system crash resistance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel system crash resistance. 27.952... crash resistance. Unless other means acceptable to the Administrator are employed to minimize the hazard of fuel fires to occupants following an otherwise survivable impact (crash landing), the fuel...

  13. Analyzing road design risk factors for run-off-road crashes in The Netherlands with crash prediction models.

    NARCIS (Netherlands)

    Petegem, J.W.H. van & Wegman, F.C.M.

    2014-01-01

    About 50% of all road traffic fatalities and 30% of all traffic injuries in The Netherlands take place on rural roads with a speed limit of 80 km/h. About 50% of these crashes are run-off-road (ROR) crashes. To reduce the number of crashes on this road type, attention should be put on improving the

  14. Vehicle dynamics and crash dynamics with minicomputer.

    NARCIS (Netherlands)

    Giavotto, V. Puccinelli, L. Borri, M. Edelman, A. & Heijer, T.

    1982-01-01

    The definition and the development of the VEDYAC system is given. Following a previous large experience concerning the simulation of crashes with safety barriers, a basic philosophy has been developed and the requirements of the VEDYAC project have been fixed. The main features of the VEDYAC project

  15. Syncope and Motor Vehicle Crash Risk

    DEFF Research Database (Denmark)

    Numé, Anna-Karin; Gislason, Gunnar; Christiansen, Christine B;

    2016-01-01

    IMPORTANCE: Syncope may have serious consequences for traffic safety. Current clinical guideline recommendations on driving following syncope are primarily based on expert consensus. OBJECTIVE: To identify whether there is excess risk of motor vehicle crashes among patients with syncope compared...... reference. RESULTS: The 41 039 patients with syncope had a median age of 66 years (interquartile range [IQR], 47-78 years); 51.0% were women; and 34.8% had cardiovascular disease. Through a median follow-up of 2.0 years (IQR, 0.8-3.3 years), 1791 patients with syncope (4.4%) had a motor vehicle crash, 78.......83 (95% CI, 1.74-1.91) after adjustment for age, sex, socioeconomic position, and relevant comorbidities and pharmacotherapy. Men had a relatively higher rate of motor vehicle crashes (RR, 1.91; 95% CI, 1.79-2.03) than women (RR, 1.74; 95% CI, 1.63-1.87). The excess risk of motor vehicle crashes...

  16. Motor Vehicle Crash Injuries PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2014-10-07

    This 60 second Public Service Announcement is based on the October 2014 CDC Vital Signs report. Motor vehicle crashes are costly and preventable. Learn what can be done to help prevent motor vehicle injuries.  Created: 10/7/2014 by National Center for Injury Prevention and Control (NCIPC).   Date Released: 10/7/2014.

  17. Vital Signs-Motor Vehicle Crash Injuries

    Centers for Disease Control (CDC) Podcasts

    2014-10-07

    This podcast is based on the October 2014 CDC Vital Signs report. Motor vehicle crashes are costly and preventable. Learn what can be done to help prevent motor vehicle injuries.  Created: 10/7/2014 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 10/7/2014.

  18. CRASH3: cosmological radiative transfer through metals

    CERN Document Server

    Graziani, L; Ciardi, B

    2012-01-01

    Here we introduce CRASH3, the latest release of the 3D radiative transfer code CRASH. In its current implementation CRASH3 integrates into the reference algorithm the code Cloudy to evaluate the ionisation states of metals, self-consistently with the radiative transfer through H and He. The feedback of the heavy elements on the calculation of the gas temperature is also taken into account, making of CRASH3 the first 3D code for cosmological applications which treats self-consistently the radiative transfer through an inhomogeneous distribution of metal enriched gas with an arbitrary number of point sources and/or a background radiation. The code has been tested in idealized configurations, as well as in a more realistic case of multiple sources embedded in a polluted cosmic web. Through these validation tests the new method has been proven to be numerically stable and convergent. We have studied the dependence of the results on a number of physical quantities such as the source characteristics (spectral range...

  19. Behaviour of a spent fuel transport-storage cask during an airplane crash

    International Nuclear Information System (INIS)

    TRANSNUCLEAIRE has got an order for the design and manufacturing of dual purpose, transport and storage, casks for spent fuel.An original item of the qualification of the design of this cask, for the storage aspect, is the necessity to demonstrate the resistance to an air crash.The typical case taken into account for design is the crash of a military fighter (F16) with a total mass of 14600kg and an impact speed of 150ms-1. The demonstration of the ability of the cask to withstand this test is provided by both calculation and test.Two cases were considered. For the first one, the projectile hits the cask at the centre of the anti-crash lid. For the second one, it hits the cask in the plane of the closure system.The first step of the qualification is based on calculations performed with a code designed to study the effects of crashes. The aim of the calculations is, mainly, to determine the missile which has to be shot, and to select the worst orientation for the impact.To provide a full justification of the acceptability of the impact as concerned leaktightness, a test has been performed on a one-third scale model. It has shown that it was not altered by the impact.The paper provides a full description of the method of analysis, results of the numerical analysis, conclusion of the test and how the combination of calculation and test demonstrates the ability of the cask to withstand an airplane crash. ((orig.))

  20. Survivors’ experiences from a train crash

    Directory of Open Access Journals (Sweden)

    Rebecca Forsberg

    2011-11-01

    Full Text Available Rarely described are people's lived experiences from severe injury events such as train crashes. The number of train crashes named disasters with ≥10 killed and/or ≥100 nonfatally injured grows globally and the trend shows that more people survive these disasters today than did so in the past. This results in an increased number of survivors needing care. The aim of the study was to explore survivors’ experiences from a train crash. Narrative interviews were performed with 14 passengers 4 years after a train crash event. Qualitative content analysis was used to analyse the interviews. Experiences were captured in three main themes: (1 Living in the mode of existential threat describes how the survivors first lost control, then were thrown into a state of unimaginable chaos as they faced death. (2 Dealing with the unthinkable described how survivors restored control, the central role of others, and the importance of reconstructing the event to move forward in their processing. (3 Having cheated death shows how some became shackled by their history, whereas others overcame the haunting of unforgettable memories. Furthermore, the result shows how all experienced a second chance in life. Experiencing a train crash meant that the passengers experienced severe vulnerability and a threat to life and interdependence turned out to play a crucial role. Focusing on helping other passengers on site was one way to regain the loss of control and kept the chaos at bay. Family, friends, and fellow passengers turned out to be extremely important during the recovery process why such closeness should be promoted and facilitated.

  1. Driver inattention and driver distraction in serious casualty crashes: data from the Australian National Crash In-depth Study.

    Science.gov (United States)

    Beanland, Vanessa; Fitzharris, Michael; Young, Kristie L; Lenné, Michael G

    2013-05-01

    Driver inattention and driver distraction represent a major problem in road safety. Although both are believed to contribute to increased crash risk, there is currently limited reliable information on their role in crashes. The current study used in-depth data from the Australian National Crash In-depth Study to investigate the role of driver distraction and inattention in serious casualty crashes. The sample included 856 crashes from 2000 to 2011, in which at least one party was admitted to hospital due to crash-related injuries. Crashes were coded using a taxonomy of driver inattention that delineates five inattention subtypes: restricted attention, misprioritised attention, neglected attention, cursory attention, and diverted attention (distraction). Approximately 45% of crashes could not be coded due to insufficient information while in an additional 15% the participant indicated the "other driver was at fault" without specifying whether inattention was involved. Of the 340 remaining cases, most showed evidence of driver inattention (57.6%) or possible inattention (5.9%). The most common subtypes of inattention were restricted attention, primarily due to intoxication and/or fatigue, and diverted attention or distraction. The most common types of distraction involved voluntary, non-driving related distractions originating within the vehicle, such as passenger interactions. The current study indicates that a majority of serious injury crashes involve driver inattention. Most forms of inattention and distraction observed are preventable. This study demonstrates the feasibility of using in-depth crash data to investigate driver inattention in casualty crashes. PMID:23499981

  2. Quaternion hermitian planes

    OpenAIRE

    Stroppel, Markus

    1993-01-01

    The quaternion hermitian planes are defined, and are characterized by certain groups of automorphisms. For this purpose, characterizations of locally compact connected translation planes (in the context of stable planes) and compact connected projective desarguesian planes are given.

  3. Gender and Age Differences among Teen Drivers in Fatal Crashes.

    Science.gov (United States)

    Swedler, David I; Bowman, Stephen M; Baker, Susan P

    2012-01-01

    To identify age and gender differences among teen drivers in fatal crashes, we analyzed FARS data for 14,026crashes during 2007-2009. Compared with female teenagers, crashes of male teenagers were significantly more likely to involve BACs of 0.08% or more (21% vs. 12%), speeding (38% vs. 25%), reckless driving (17% vs. 14%), night driving (41% vs. 36%) and felony crashes (hit-and-run, homicide, or manslaughter) (8% vs. 6%) (all χ(2) p<0.001). Conversely, crashes of female teenagers were more likely to involve right angle ("t-bone") crashes (23% vs. 17%). Some crash characteristics associated with males and known to play a major role in crash causation also are more common in the youngest teenagers; for example, crashes of drivers age 15 or 16 were more likely than crashes of older teens to involve speeding or reckless driving. Crashes of drivers with BACs of 0.08% or higher increased with age in both genders. Some age effects differed by gender: for example, the proportion of crashes of female teens that involved speeding dropped from 38% to 22% between ages 15 and 19, while for males about 38% of crashes at each age involved speeding. The gender and age differences observed in teen drivers suggest opportunities for targeted driver training - for example, simulator training modules specifically tailored for male or female teenagers. Technology-based tools could also be developed to help parents to focus on the reckless driving tendencies of their sons. Insurance companies should consider ways to incentivize young males to drive more responsibly. PMID:23169121

  4. Analysis of Aircraft Crash Accident for WETF

    International Nuclear Information System (INIS)

    This report applies the methodology of DOE-STD-3014-96, ''Accident Analysis for Aircraft Crash into Hazardous Facilities'', to the Weapons Engineering Tritium Facility (WETF) at LANL. Straightforward application of that methodology shows that including local helicopter flights with those of all other aircraft with potential to impact the facility poses a facility impact risk slightly in excess of the DOE standard's threshold--10-6 impacts per year. It is also shown that helicopters can penetrate the facility if their engines impact that facility's roof. However, a refinement of the helicopter impact analysis shows that penetration risk of the facility for all aircraft lies below the DOE standard's threshold. By that standard, therefore, the potential for release of hazardous material from the facility as a result of an aircraft crashing into the facility is negligible and need not be analyzed further

  5. Explaining Differences in Crash and Injury Crash Outcomes in Red Light Camera Studies.

    Science.gov (United States)

    Langland-Orban, Barbara; Pracht, Etienne E; Large, John T; Zhang, Nanhua; Tepas, Joseph T

    2016-06-01

    Evaluations of red light camera (RLC) traffic safety programs have produced mixed results. Some conclude RLCs were associated with significant increases in motor vehicle crashes and injury crashes, whereas other research reports safety benefits. To understand the difference in findings, the present analysis assessed whether standards required for internal validity in quasi-experimental public health program evaluations were adhered to in frequently cited RLC analyses. Four evaluation standards were identified and used to assess the RLC analyses: lack of bias in the selection of both (a) treated sites and (b) comparison sites, (c) integration of relevant control variables in the analysis, and (d) full disclosure of results of the statistical analysis. Six leading RLC studies were then critiqued. Only two of the six studies adhered to the four standards and both concluded RLCs were associated with significant increases in crashes and injury or possible injury crashes. A third study reported an increase in fatal/injury crashes but did not test for statistical significance. Three studies reported equivocal findings; however, each failed to adhere to most standards. Differences in findings were attributed to the evaluation methods used. If implementing an RLC program, communities should use sound public health evaluation methods to assess effectiveness. PMID:25007792

  6. Modeling Situation Awareness and Crash Risk

    OpenAIRE

    Fisher, Donald L.; Strayer, David L.

    2014-01-01

    In this article we develop a model of the relationship between crash risk and a driver’s situation awareness. We consider a driver’s situation awareness to reflect the dynamic mental model of the driving environment and to be dependent upon several psychological processes including Scanning the driving environment, Predicting and anticipating hazards, Identifying potential hazards in the driving scene as they occur, Deciding on an action, and Executing an appropriate Response (SPIDER). Togeth...

  7. Can analyst predict stock market crashes?

    OpenAIRE

    Chong, Terence T. L.; Xiaolei Wang

    2013-01-01

    The frequency of financial market turmoil has been rising over the past two decades. While the incidence of market turmoil has increased, the performance of analysts during tumultuous times has not received much attention in the literature. This paper examines whether the accuracy of analyst forecasts on stock returns varies during tumultuous times. Our results indicate that analysts' forecast performance during stock market crashes drops significantly.

  8. Deleveraging, short sale constraints and market crash

    OpenAIRE

    Wu, Liang; Zhang, Lei; Fu, Zhiming

    2015-01-01

    In this paper, we develop a theory of market crashes resulting from a deleveraging shock. We consider two representative investors in a market holding different opinions about the public available information. The deleveraging shock forces the high confidence investors to liquidate their risky assets to pay back their margin loans. When short sales are constrained, the deleveraging shock creates a liquidity vacuum in which no trades can occur between the two representative investors until the...

  9. Motor Vehicle Crash Deaths PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2016-07-06

    This 60 second public service announcement is based on the July 2016 CDC Vital Signs report. In the U.S., about 90 people die in motor vehicle crashes each day and thousands more are injured, resulting in hundreds of millions of dollars in direct medical costs each year. Learn what you can do to stay safe.  Created: 7/6/2016 by National Center for Injury Prevention and Control (NCIPC).   Date Released: 7/6/2016.

  10. Injury Patterns in Side Pole Crashes

    OpenAIRE

    Pintar, Frank A.; Maiman, Dennis J.; Yoganandan, Narayan

    2007-01-01

    Side impact pole/tree crashes can have devastating consequences. A series of 53 CIREN cases of narrow-object side impacts were analyzed. Twenty-seven of 53 had serious chest injury and 27 had serious head injury. Unilateral chest trauma led to the examination of residual crush pattern that often demonstrated oblique door intrusion into the occupant thorax space. It was hypothesized that unilateral chest trauma was caused by antero-lateral chest loading. This hypothesis was evaluated by conduc...

  11. The Stock Market Crashes of 1929 and 1987: Linking History and Personal Finance Education

    Science.gov (United States)

    Lopus, Jane S.

    2005-01-01

    This article discusses two twentieth-century stock market crashes: the crash of 1929 and the crash of 1987. When this material is presented to students, they see important parallels between the two historical events. But despite remarkable similarities in the severity and many other aspects of the two crashes, the crash of 1929 was followed by the…

  12. 41 CFR 102-34.295 - To whom do we send crash reports?

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false To whom do we send crash... MANAGEMENT Motor Vehicle Crash Reporting § 102-34.295 To whom do we send crash reports? Send crash reports as... agency directives. (b) If the motor vehicle is leased from GSA Fleet, report the crash to GSA...

  13. Signal analysis, modeling and simulation of vehicle crash dynamics

    OpenAIRE

    Midjena, Debela Yadeta; Muraspahic, Sanin

    2013-01-01

    Vehicle crash safety has been a strong point of interest for long time in many countries due to the reason that safety statistics show high fatality rate of vehicle occupants involved in road accidents. All vehicles which are going to appear on the road must go through several serious crash investigations to approve whether they conform to the relevant safety standards. There are large crash test facilities built by big companies for these operations. However, a wide and full-scal...

  14. Performing Network Level Crash Evaluation Using Skid Resistance

    OpenAIRE

    McCarthy, Ross James

    2015-01-01

    Evaluation of crash count data as a function of roadway characteristics allows Departments of Transportation to predict expected average crash risks in order to assist in identifying segments that could benefit from various treatments. Currently, the evaluation is performed using negative binomial regression, as a function of average annual daily traffic (AADT) and other variables. For this thesis, a crash study was carried out for the interstate, primary and secondary routes, in the...

  15. On the Fatal Crash Experience of Older Drivers

    OpenAIRE

    Kent, Richard; Henary, Basem; Matsuoka, Fumio

    2005-01-01

    This study describes the fatal crash experiences of older drivers. Data from two U.S. databases (NASS-CDS and FARS) were used. Several crash, vehicle, and occupant characteristics were compared across age groups, including vehicle type, crash direction (PDOF), severity (ΔV), and injured body region. A sub-set of 97 fatally injured drivers was chosen for a detailed case study. The mean travel speed, ΔV, and airbag deployment rate decreased significantly with age (p

  16. Automated Vehicle Crash Rate Comparison Using Naturalistic Data

    OpenAIRE

    Blanco, Myra; Atwood, Jon; Russell, Sheldon; Trimble, Tammy; McClafferty, Julie; Perez, Miguel

    2016-01-01

    This study assessed driving risk for the United States nationally and for the Google Self-Driving Car project. Driving safety on public roads was examined in three ways. The total crash rates for the Self-Driving Car and the national population were compared to (1) rates reported to the police, (2) crash rates for different types of roadways, and (3) scenarios that give rise to unreported crashes. First, crash rates from the Google Self-Driving Car project per million miles driven, broken dow...

  17. Offsite radiological consequence analysis for the bounding aircraft crash accident

    International Nuclear Information System (INIS)

    The purpose of this calculation note is to quantitatively analyze a bounding aircraft crash accident for comparison to the DOE-STD-3009-94, ''Preparation Guide for U.S. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', Appendix A, Evaluation Guideline of 25 rem. The potential of aircraft impacting a facility was evaluated using the approach given in DOE-STD-3014-96, ''Accident Analysis for Aircraft Crash into Hazardous Facilities''. The following aircraft crash FR-equencies were determined for the Tank Farms in RPP-11736, ''Assessment Of Aircraft Crash FR-equency For The Hanford Site 200 Area Tank Farms'': (1) The total aircraft crash FR-equency is ''extremely unlikely.'' (2) The general aviation crash FR-equency is ''extremely unlikely.'' (3) The helicopter crash FR-equency is ''beyond extremely unlikely.'' (4) For the Hanford Site 200 Areas, other aircraft type, commercial or military, each above ground facility, and any other type of underground facility is ''beyond extremely unlikely.'' As the potential of aircraft crash into the 200 Area tank farms is more FR-equent than ''beyond extremely unlikely,'' consequence analysis of the aircraft crash is required

  18. Injury Risk Functions in Frontal Impacts Using Data from Crash Pulse Recorders

    OpenAIRE

    Stigson, Helena; Kullgren, Anders; Rosén, Erik

    2012-01-01

    Knowledge of how crash severity influences injury risk in car crashes is essential in order to create a safe road transport system. Analyses of real-world crashes increase the ability to obtain such knowledge.

  19. 77 FR 29247 - Federal Motor Vehicle Safety Standards; Occupant Crash Protection

    Science.gov (United States)

    2012-05-17

    ... Standards; Occupant Crash Protection AGENCY: National Highway Traffic Safety Administration (NHTSA... technical amendments to Federal Motor Vehicle Safety Standard (FMVSS) No. 208, Occupant Crash Protection... requirements for pressure vessels and explosive devices used in occupant crash protection systems, such as...

  20. Crash protection of stock car racing drivers--application of biomechanical analysis of Indy car crash research.

    Science.gov (United States)

    Melvin, John W; Begeman, Paul C; Faller, Ronald K; Sicking, Dean L; McClellan, Scott B; Maynard, Edwin; Donegan, Michael W; Mallott, Annette M; Gideon, Thomas W

    2006-11-01

    Biomechanical analysis of Indy car crashes using on-board impact recorders (Melvin et al. 1998, Melvin et al. 2001) indicates that Indy car driver protection in high-energy crashes can be achieved in frontal, side, and rear crashes with severities in the range of 100 to 135 G peak deceleration and velocity changes in the range of 50 to 70 mph. These crashes were predominantly single-car impacts with the rigid concrete walls of oval tracks. This impressive level of protection was found to be due to the unique combination of a very supportive and tight-fitting cockpit-seating package, a six-point belt restraint system, and effective head padding with an extremely strong chassis that defines the seat and cockpit of a modern Indy car. In 2000 and 2001, a series of fatal crashes in stock car racing created great concern for improving the crash protection for drivers in those racecars. Unlike the Indy car, the typical racing stock car features a more spacious driver cockpit due to its resemblance to the shape of a passenger car. The typical racing seat used in stock cars did not have the same configuration or support characteristics of the Indy car seat, and five-point belt restraints were used. The tubular steel space frame chassis of a stock car also differs from an Indy car's composite chassis structure in both form and mechanical behavior. This paper describes the application of results of the biomechanical analysis of the Indy car crash studies to the unique requirements of stock car racing driver crash protection. Sled test and full-scale crash test data using both Hybrid III frontal crash anthropomorphic test devices (ATDs) and BioSID side crash ATDs for the purpose of evaluating countermeasures involving restraint systems, seats and head/neck restraints has been instrumental in guiding these developments. In addition, the development of deformable walls for oval tracks (the SAFER Barrier) is described as an adjunct to improved occupant restraint through control

  1. Sawtooth crashes at high beta on JET

    Energy Technology Data Exchange (ETDEWEB)

    Alper, B.; Huysmans, G.T.A.; Sips, A.C.C. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Nave, M.F.F. [Universidade Tecnica, Lisbon (Portugal). Inst. Superior Tecnico

    1994-07-01

    The sawtooth crashes on JET display features which depend on beta. The main observation is a transient bulging of flux surfaces (duration inferior to 30 microsec.), which is predominantly on the low field side and extends to larger radii as beta increases. This phenomenon reaches the plasma boundary when beta{sub N} exceeds 0.5 and in these cases is followed by an ELM within 50 microsec. These sawtooth/ELM events limit plasma performance. Modelling of mode coupling shows qualitative agreement between observations of the structure of the sawtooth precursor and the calculated internal kink mode at high beta. (authors). 6 refs., 5 figs.

  2. Data Mining on Crash Simulation Data

    OpenAIRE

    Kuhlmann, A.; Vetter, R. -M.; Luebbing, Ch.; Thole, C. -A.

    2005-01-01

    The work presented in this paper is part of the cooperative research project AUTO-OPT carried out by twelve partners from the automotive industries. One major work package concerns the application of data mining methods in the area of automotive design. Suitable methods for data preparation and data analysis are developed. The objective of the work is the re-use of data stored in the crash-simulation department at BMW in order to gain deeper insight into the interrelations between the geometr...

  3. Mechanisms of injury in automobile crashes.

    Science.gov (United States)

    Huelke, D F

    1972-02-01

    The only way to determine the causes of injury in automobile collisions is through examination of data collected in detailed investigation of crashes. Such data were gathered from a ten-year study of collisions that caused injury to the occupants of the cars. In a comparison of injuries in the newer model automobiles-vehicles equipped with the safety features-with those in older model cars not equipped with the present-day occupant protection devices, significant reduction in injury severity was noted. PMID:5059662

  4. Innovative Anti Crash Absorber for a Crashworthy Landing Gear

    Science.gov (United States)

    Guida, Michele; Marulo, Francesco; Montesarchio, Bruno; Bruno, Massimiliano

    2014-06-01

    This paper defines an innovative concept to anti-crash absorber in composite material to be integrated on the landing gear as an energy-absorbing device in crash conditions to absorb the impact energy. A composite cylinder tube in carbon fiber material is installed coaxially to the shock absorber cylinder and, in an emergency landing gear condition, collapses in order to enhance the energy absorption performance of the landing system. This mechanism has been developed as an alternative solution to a high-pressure chamber installed on the Agusta A129 CBT helicopter, which can be considered dangerous when the helicopter operates in hard and/or crash landing. The characteristics of the anti-crash device are presented and the structural layout of a crashworthy landing gear adopting the developed additional energy absorbing stage is outlined. Experimental and numerical results relevant to the material characterization and the force peaks evaluation of the system development are reported. The anti-crash prototype was designed, analysed, optimized, made and finally the potential performances of a landing gear with the additional anti-crash absorber system are tested by drop test and then correlated with a similar test without the anti-crash system, showing that appreciable energy absorbing capabilities and efficiencies can be obtained in crash conditions.

  5. Analyzing angle crashes at unsignalized intersections using machine learning techniques.

    Science.gov (United States)

    Abdel-Aty, Mohamed; Haleem, Kirolos

    2011-01-01

    A recently developed machine learning technique, multivariate adaptive regression splines (MARS), is introduced in this study to predict vehicles' angle crashes. MARS has a promising prediction power, and does not suffer from interpretation complexity. Negative Binomial (NB) and MARS models were fitted and compared using extensive data collected on unsignalized intersections in Florida. Two models were estimated for angle crash frequency at 3- and 4-legged unsignalized intersections. Treating crash frequency as a continuous response variable for fitting a MARS model was also examined by considering the natural logarithm of the crash frequency. Finally, combining MARS with another machine learning technique (random forest) was explored and discussed. The fitted NB angle crash models showed several significant factors that contribute to angle crash occurrence at unsignalized intersections such as, traffic volume on the major road, the upstream distance to the nearest signalized intersection, the distance between successive unsignalized intersections, median type on the major approach, percentage of trucks on the major approach, size of the intersection and the geographic location within the state. Based on the mean square prediction error (MSPE) assessment criterion, MARS outperformed the corresponding NB models. Also, using MARS for predicting continuous response variables yielded more favorable results than predicting discrete response variables. The generated MARS models showed the most promising results after screening the covariates using random forest. Based on the results of this study, MARS is recommended as an efficient technique for predicting crashes at unsignalized intersections (angle crashes in this study). PMID:21094345

  6. Euclid Squares on Infinite Planes

    OpenAIRE

    W.B.Vasantha Kandasamy; Ilanthenral, K.; Florentin Smarandache

    2015-01-01

    In this book for the first time the authors study the new type of Euclid squares in various planes like real plane, complex plane, dual number plane, special dual like number plane and special quasi dual number plane.

  7. Impact of traffic states on freeway crash involvement rates.

    Science.gov (United States)

    Yeo, Hwasoo; Jang, Kitae; Skabardonis, Alexander; Kang, Seungmo

    2013-01-01

    Freeway traffic accidents are complicated events that are influenced by multiple factors including roadway geometry, drivers' behavior, traffic conditions and environmental factors. Among the various factors, crash occurrence on freeways is supposed to be strongly influenced by the traffic states representing driving situations that are changed by road geometry and cause the change of drivers' behavior. This paper proposes a methodology to investigate the relationship between traffic states and crash involvements on the freeway. First, we defined section-based traffic states: free flow (FF), back of queue (BQ), bottleneck front (BN) and congestion (CT) according to their distinctive patterns; and traffic states of each freeway section are determined based on actual measurements of traffic data from upstream and downstream ends of the section. Next, freeway crash data are integrated with the traffic states of a freeway section using upstream and downstream traffic measurements. As an illustrative study to show the applicability, we applied the proposed method on a 32-mile section of I-880 freeway. By integrating freeway crash occurrence and traffic data over a three-year period, we obtained the crash involvement rate for each traffic state. The results show that crash involvement rate in BN, BQ, and CT states are approximately 5 times higher than the one in FF. The proposed method shows promise to be used for various safety performance measurement including hot spot identification and prediction of the number of crash involvements on freeway sections. PMID:22795398

  8. Countermeasures for Reducing Alcohol-Related Crashes.

    Science.gov (United States)

    Voas, R B

    2000-01-01

    Programs to prevent alcohol-related crashes occur at several levels. Although most of the public thinks of drunk-driving prevention only in terms of the criminal justice system, much can be done to prevent alcohol-related highway deaths before the drinking-and-driving offender gets on the road. In recent years, the field of alcohol safety has merged with the area of public health concerned with preventing alcohol- and drug-related traumatic injury and death. This paper provides an overview of the status of road safety programs directed at reducing impaired driving. It covers ten topics falling into the three levels of prevention: primary programs to reduce alcohol consumption; secondary programs to prevent driving after drinking; and tertiary programs to prevent recidivism among convicted drinking drivers. PMID:26256029

  9. Bayesian log-periodic model for financial crashes

    DEFF Research Database (Denmark)

    Rodríguez-Caballero, Carlos Vladimir; Knapik, Oskar

    2014-01-01

    This paper introduces a Bayesian approach in econophysics literature about financial bubbles in order to estimate the most probable time for a financial crash to occur. To this end, we propose using noninformative prior distributions to obtain posterior distributions. Since these distributions...... part of the study, we analyze a well-known example of financial bubble – the S&P 500 1987 crash – to show the usefulness of the three methods under consideration and crashes of Merval-94, Bovespa-97, IPCMX-94, Hang Seng-97 using the simplest method. The novelty of this research is that the Bayesian...

  10. Projecting Fatalities in Crashes Involving Older Drivers, 2000-2025

    Energy Technology Data Exchange (ETDEWEB)

    Hu, P.S.

    2001-03-23

    As part of this research effort, we developed a new methodology for projecting elderly traffic crash fatalities. This methodology separates exposure to crashes from crash risk per se, and further divides exposure into two components, the number of miles driven and the likelihood of being a driver. This component structure permits conceptually different determinants of traffic fatalities to be projected separately and has thorough motivation in behavioral theory. It also permits finer targeting of particular aspects of projections that need improvement and closer linking of projections to possible policy instruments for influencing them.

  11. Evaluation of the First Transport Rotorcraft Airframe Crash Testbed (TRACT 1) Full-Scale Crash Test

    Science.gov (United States)

    Annett, Martin S.; Littell, Justin D.; Jackson, Karen E.; Bark, Lindley W.; DeWeese, Rick L.; McEntire, B. Joseph

    2014-01-01

    In 2012, the NASA Rotary Wing Crashworthiness Program initiated the Transport Rotorcraft Airframe Crash Testbed (TRACT) research program by obtaining two CH-46E helicopters from the Navy CH-46E Program Office (PMA-226) at the Navy Flight Readiness Center in Cherry Point, North Carolina. Full-scale crash tests were planned to assess dynamic responses of transport-category rotorcraft under combined horizontal and vertical impact loading. The first crash test (TRACT 1) was performed at NASA Langley Research Center's Landing and Impact Research Facility (LandIR), which enables the study of critical interactions between the airframe, seat, and occupant during a controlled crash environment. The CH-46E fuselage is categorized as a medium-lift rotorcraft with fuselage dimensions comparable to a regional jet or business jet. The first TRACT test (TRACT 1) was conducted in August 2013. The primary objectives for TRACT 1 were to: (1) assess improvements to occupant loads and displacement with the use of crashworthy features such as pre-tensioning active restraints and energy absorbing seats, (2) develop novel techniques for photogrammetric data acquisition to measure occupant and airframe kinematics, and (3) provide baseline data for future comparison with a retrofitted airframe configuration. Crash test conditions for TRACT 1 were 33-ft/s forward and 25-ft/s vertical combined velocity onto soft soil, which represent a severe, but potentially survivable impact scenario. The extraordinary value of the TRACT 1 test was reflected by the breadth of meaningful experiments. A total of 8 unique experiments were conducted to evaluate ATD responses, seat and restraint performance, cargo restraint effectiveness, patient litter behavior, and photogrammetric techniques. A combination of Hybrid II, Hybrid III, and ES-2 Anthropomorphic Test Devices (ATDs) were placed in forward and side facing seats and occupant results were compared against injury criteria. Loads from ATDs in energy

  12. Injury Risk for Rear-Seated Occupants in Small Overlap Crashes

    OpenAIRE

    Arbogast, Kristy B.; Locey, Caitlin M.; Hammond, Rachel; Belwadi, Aditya

    2013-01-01

    Small overlap crashes, where the primary crash engagement is outboard from the longitudinal energy absorbing structures of the vehicle, have received recent interest as a crash dynamic that results in high likelihood of injury. Previous analyses of good performing vehicles showed that 24% of crashes with AIS 3+ injuries to front seat occupants were small overlap crashes. However, similar evaluations have not been conducted for those rear seated. Vehicle dynamics suggest that rear seat occupan...

  13. Linux Crash Dump的设计与实现%AN INTRODUCTION TO DESIGN AND IMPLEMENTATION OF Linux Crash Dump

    Institute of Scientific and Technical Information of China (English)

    王勇; 沈亚谦; 潘金贵

    2002-01-01

    本文介绍了Linux Crash Dump的设计与实现方法.Linux Crash Dump提供了一种保存系统在发生Crash时内存映象的能力.通过对Dump结果的分析,可以有效地帮助诊断系统出错的原因.本文介绍了如何进行Crash Dump,以及Dump的数据的组织和保存方法等.

  14. A multinomial-logit ordered-probit model for jointly analyzing crash avoidance maneuvers and crash severity

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    the United States National Automotive Sampling System General Estimates System (GES) crash database for the years 2005-2009. Results show (i) the correlation between crash avoidance maneuvers and crash severity, and (ii) the link between drivers' attributes, risky driving behavior, road......' propensity to engage in various corrective maneuvers in the case of the critical event of vehicle travelling. Five lateral and speed control maneuvers are considered: “braking”, “steering”, “braking & steering”, and “other maneuvers”, in addition to a “no action” option. The analyzed data are retrieved from...

  15. Lighter and stronger planes

    OpenAIRE

    Attard, Bonnie; Duca, Edward

    2015-01-01

    The price of fuel is a large cost burden on the aerospace industry. A lighter plane means cheaper flights, increased aircraft range, and less environmental pollution. http://www.um.edu.mt/think/lighter-and-stronger-planes/

  16. Why Do Markets Crash? Bitcoin Data Offers Unprecedented Insights.

    Directory of Open Access Journals (Sweden)

    Jonathan Donier

    Full Text Available Crashes have fascinated and baffled many canny observers of financial markets. In the strict orthodoxy of the efficient market theory, crashes must be due to sudden changes of the fundamental valuation of assets. However, detailed empirical studies suggest that large price jumps cannot be explained by news and are the result of endogenous feedback loops. Although plausible, a clear-cut empirical evidence for such a scenario is still lacking. Here we show how crashes are conditioned by the market liquidity, for which we propose a new measure inspired by recent theories of market impact and based on readily available, public information. Our results open the possibility of a dynamical evaluation of liquidity risk and early warning signs of market instabilities, and could lead to a quantitative description of the mechanisms leading to market crashes.

  17. Why Do Markets Crash? Bitcoin Data Offers Unprecedented Insights.

    Science.gov (United States)

    Donier, Jonathan; Bouchaud, Jean-Philippe

    2015-01-01

    Crashes have fascinated and baffled many canny observers of financial markets. In the strict orthodoxy of the efficient market theory, crashes must be due to sudden changes of the fundamental valuation of assets. However, detailed empirical studies suggest that large price jumps cannot be explained by news and are the result of endogenous feedback loops. Although plausible, a clear-cut empirical evidence for such a scenario is still lacking. Here we show how crashes are conditioned by the market liquidity, for which we propose a new measure inspired by recent theories of market impact and based on readily available, public information. Our results open the possibility of a dynamical evaluation of liquidity risk and early warning signs of market instabilities, and could lead to a quantitative description of the mechanisms leading to market crashes. PMID:26448333

  18. Crash Prediction and Risk Evaluation Based on Traffic Analysis Zones

    Directory of Open Access Journals (Sweden)

    Cuiping Zhang

    2014-01-01

    Full Text Available Traffic safety evaluation for traffic analysis zones (TAZs plays an important role in transportation safety planning and long-range transportation plan development. This paper aims to present a comprehensive analysis of zonal safety evaluation. First, several criteria are proposed to measure the crash risk at zonal level. Then these criteria are integrated into one measure-average hazard index (AHI, which is used to identify unsafe zones. In addition, the study develops a negative binomial regression model to statistically estimate significant factors for the unsafe zones. The model results indicate that the zonal crash frequency can be associated with several social-economic, demographic, and transportation system factors. The impact of these significant factors on zonal crash is also discussed. The finding of this study suggests that safety evaluation and estimation might benefit engineers and decision makers in identifying high crash locations for potential safety improvements.

  19. Heavy Vehicle Crash Characteristics in Oman; 2009–2011

    Directory of Open Access Journals (Sweden)

    Islam Al-Bulushi

    2015-05-01

    Full Text Available In recent years, Oman has seen a shift in the burden of diseases towards road accidents. The main objective of this paper, therefore, is to describe key characteristics of heavy vehicle crashes in Oman and identify the key driving behaviours that influence fatality risks. Crash data from January 2009 to December 2011 were examined and it was found that, of the 22,543 traffic accidents that occurred within this timeframe, 3,114 involved heavy vehicles. While the majority of these crashes were attributed to driver behaviours, a small proportion was attributed to other factors. The results of the study indicate that there is a need for a more thorough crash investigation process in Oman. Future research should explore the reporting processes used by the Royal Oman Police, cultural influences on heavy vehicle operations in Oman and improvements to the current licensing system.

  20. Determinants of road traffic crash fatalities across Indian States

    NARCIS (Netherlands)

    M. Grimm (Michael); C. Treibich (Carole)

    2012-01-01

    textabstractObjective: This paper explores the determinants of road traffic crash fatalities in India. As potential factors, the analysis considers, besides income, the sociodemographic populationstructure, motorization levels, road and health infrastructure and road rule enforcement. Methods: An or

  1. Finite Element Crash Simulations and Impact-Induced Injuries

    Directory of Open Access Journals (Sweden)

    Jaroslav Mackerle

    1999-01-01

    Full Text Available This bibliography lists references to papers, conference proceedings and theses/dissertations dealing with finite element simulations of crashes, impact-induced injuries and their protection that were published in 1980–1998. 390 citations are listed.

  2. Relationship between organisational safety culture dimensions and crashes.

    Science.gov (United States)

    Varmazyar, Sakineh; Mortazavi, Seyed Bagher; Arghami, Shirazeh; Hajizadeh, Ebrahim

    2016-01-01

    Knowing about organisational safety culture in public transportation system can provide an appropriate guide to establish effective safety measures and interventions to improve safety at work. The aim of this study was investigation of association between safety culture dimensions (leadership styles and company values, usage of crashes information and prevention programmes, management commitment and safety policy, participation and control) with involved self-reported crashes. The associations were considered through Spearman correlation, Pearson chi-square test and logistic regression. The results showed an association among self-reported crashes (occurrence or non-occurrence) and factors including leadership styles and company values; management commitment and safety policy; and control. Moreover, it was found a negative correlation and an odds ratio less than one between control and self-reported crashes. PMID:25494102

  3. The impact of Crisis Communication on audience: A study based on plane crash

    OpenAIRE

    Chan, Calvin

    2007-01-01

    Organisational crises have now become as common as having a cold. Crises negatively affect the company's reputation and share price. Maintaining a reputation has today become paramount. Therefore, post-crisis communication is absolutely essential and has to be planned carefully. Poor crisis communication would leave the audience or the public with bad impression over the company. The poor crisis communication may even extend the bad impression over the whole industry. In responding to th...

  4. Crash Risk Reduction at Signalized Intersections Using Longitudinal Data

    OpenAIRE

    Mark L. Burkey; Obeng, Kofi

    2005-01-01

    This study extends the previous work of Burkey and Obeng (2004) that examined the impact of red light cameras on the type and severity of crashes at signalized intersections in Greensboro, NC. The extension takes the following form. First, we extend the data to cover 57 months, and to include demographics, technology variables, the condition of a driver at the time of the crash, vehicle characteristics, land use and visual obstruction. Second, instead of examining the impact of re...

  5. Studying the effect of weather conditions on daily crash counts

    OpenAIRE

    Brijs, Tom; Karlis, Dimitris; Wets, Geert

    2007-01-01

    In previous research, significant effects of weather conditions on car crashes have been found. However, most studies use monthly or yearly data and only few studies are available analyzing the impact of weather conditions on daily car crash counts. Furthermore, the studies that are available on a daily level do not model the data in a time-series context, hereby ignoring the temporal serial correlation that may be present in the data. In this paper, we introduce an Integer Autoregressive mod...

  6. A fuzzy logic approach to modeling a vehicle crash test

    OpenAIRE

    Pawlus, Witold; Karimi, Hamid Reza; Robbersmyr, Kjell G.

    2012-01-01

    This paper presents an application of fuzzy approach to vehicle crash modeling. A typical vehicle to pole collision is described and kinematics of a car involved in this type of crash event is thoroughly characterized. The basics of fuzzy set theory and modeling principles based on fuzzy logic approach are presented. In particular, exceptional attention is paid to explain the methodology of creation of a fuzzy model of a vehicle collision. Furthermore, the simulation results are presented and...

  7. Dynamics of a financial market index after a crash

    OpenAIRE

    Fabrizio Lillo; Mantegna, Rosario N.

    2002-01-01

    We discuss the statistical properties of index returns in a financial market just after a major market crash. The observed non-stationary behavior of index returns is characterized in terms of the exceedances over a given threshold. This characterization is analogous to the Omori law originally observed in geophysics. By performing numerical simulations and theoretical modelling, we show that the nonlinear behavior observed in real market crashes cannot be described by a GARCH(1,1) model. We ...

  8. Trade Deficit News, Systematic Risk and the Crash of 1987

    OpenAIRE

    Willem Thorbecke

    1994-01-01

    News of enormous trade deficits began affecting asset prices in the mid-1980s. Some have suggested that trade deficit news contributed to the October 1987 stock market crash. This argument would be more compelling if the trade deficit were a source of systematic risk to asset prices, since then trade deficit news could have contributed to the increased perception of the riskiness of holding equities that occurred just before the crash. Here the Arbitrage Pricing Theory is used to demonstrate ...

  9. Statistical modeling of total crash frequency at highway intersections

    Directory of Open Access Journals (Sweden)

    Arash M. Roshandeh

    2016-04-01

    Full Text Available Intersection-related crashes are associated with high proportion of accidents involving drivers, occupants, pedestrians, and cyclists. In general, the purpose of intersection safety analysis is to determine the impact of safety-related variables on pedestrians, cyclists and vehicles, so as to facilitate the design of effective and efficient countermeasure strategies to improve safety at intersections. This study investigates the effects of traffic, environmental, intersection geometric and pavement-related characteristics on total crash frequencies at intersections. A random-parameter Poisson model was used with crash data from 357 signalized intersections in Chicago from 2004 to 2010. The results indicate that out of the identified factors, evening peak period traffic volume, pavement condition, and unlighted intersections have the greatest effects on crash frequencies. Overall, the results seek to suggest that, in order to improve effective highway-related safety countermeasures at intersections, significant attention must be focused on ensuring that pavements are adequately maintained and intersections should be well lighted. It needs to be mentioned that, projects could be implemented at and around the study intersections during the study period (7 years, which could affect the crash frequency over the time. This is an important variable which could be a part of the future studies to investigate the impacts of safety-related works at intersections and their marginal effects on crash frequency at signalized intersections.

  10. Structural Integrity Assessment of Reactor Containment Subjected to Aircraft Crash

    International Nuclear Information System (INIS)

    When an accident occurs at the NPP, containment building which acts as the last barrier should be assessed and analyzed structural integrity by internal loading or external loading. On many occasions that can occur in the containment internal such as LOCA(Loss Of Coolant Accident) are already reflected to design. Likewise, there are several kinds of accidents that may occur from the outside of containment such as earthquakes, hurricanes and strong wind. However, aircraft crash that at outside of containment is not reflected yet in domestic because NPP sites have been selected based on the probabilistic method. After intentional aircraft crash such as World Trade Center and Pentagon accident in US, social awareness for safety of infrastructure like NPP was raised world widely and it is time for assessment of aircraft crash in domestic. The object of this paper is assessment of reactor containment subjected to aircraft crash by FEM(Finite Element Method). In this paper, assessment of structural integrity of containment building subjected to certain aircraft crash was carried out. Verification of structure integrity of containment by intentional severe accident. Maximum stress 61.21MPa of horizontal shell crash does not penetrate containment. Research for more realistic results needed by steel reinforced concrete model

  11. Linux Crash Dump分析工具的设计与实现%The Design and Implementation of an Analysis Tool of Linux Crash Dump

    Institute of Scientific and Technical Information of China (English)

    沈亚谦; 王勇; 潘金贵

    2002-01-01

    提出了一种利用Linux Crash Dump以及对Dump的分析来进行Linux系统调试的方法.着重描述了在目前Linux系统中添加Crash Dump功能的方法和Linux Crash Dump分析工具的具体实现方案.

  12. Investigating the Effects of Side Airbag Deployment in Real-World Crashes Using Crash Comparison Techniques

    OpenAIRE

    Loftis, Kathryn L.; Weaver, Ashley A.; Stitzel, Joel D.

    2011-01-01

    The objective of this study was to investigate side airbag (SAB) deployment in near side crashes and compare injuries and contact points between occupants with and without SAB deployment. Using NASS 2000–2008 and selecting for near side cases, with PDOF ± 20 degrees from 90 or 270, for non-pregnant adult belted occupants, there were 20,253 (weighted) SAB deployments. NASS showed that SABs have been increasing within the fleet, comprising 2% of airbags in 2000 and increasing to 33% of airbags ...

  13. Modeling Composite Laminate Crushing for Crash Analysis

    Science.gov (United States)

    Fleming, David C.; Jones, Lisa (Technical Monitor)

    2002-01-01

    Crash modeling of composite structures remains limited in application and has not been effectively demonstrated as a predictive tool. While the global response of composite structures may be well modeled, when composite structures act as energy-absorbing members through direct laminate crushing the modeling accuracy is greatly reduced. The most efficient composite energy absorbing structures, in terms of energy absorbed per unit mass, are those that absorb energy through a complex progressive crushing response in which fiber and matrix fractures on a small scale dominate the behavior. Such failure modes simultaneously include delamination of plies, failure of the matrix to produce fiber bundles, and subsequent failure of fiber bundles either in bending or in shear. In addition, the response may include the significant action of friction, both internally (between delaminated plies or fiber bundles) or externally (between the laminate and the crushing surface). A figure shows the crushing damage observed in a fiberglass composite tube specimen, illustrating the complexity of the response. To achieve a finite element model of such complex behavior is an extremely challenging problem. A practical crushing model based on detailed modeling of the physical mechanisms of crushing behavior is not expected in the foreseeable future. The present research describes attempts to model composite crushing behavior using a novel hybrid modeling procedure. Experimental testing is done is support of the modeling efforts, and a test specimen is developed to provide data for validating laminate crushing models.

  14. Crash testing of nuclear fuel shipping containers

    International Nuclear Information System (INIS)

    In an attempt to understand the dynamics of extra severe transportation accidents and to evaluate state-of-the-art computational techniques for predicting the dynamic response of shipping casks involved in vehicular system crashes, the Environmental Control Technology Division of ERDA undertook a program with Sandia to investigate these areas. The program encompasses the following distinct major efforts. The first of these utilizes computational methods for predicting the effects of the accident environment and, subsequently, to calculate the damage incurred by a container as the result of such an accident. The second phase involves the testing of 1/8-scale models of transportation systems. Through the use of instrumentation and high-speed motion photography the accident environments and physical damage mechanisms are studied in detail. After correlating the results of these first two phases, a full scale event involving representative hardware is conducted. To date two of the three selected test scenarios have been completed. Results of the program to this point indicate that both computational techniques and scale modeling are viable engineering approaches to studying accident environments and physical damage to shipping casks

  15. Cervical spine response in frontal crash.

    Science.gov (United States)

    Panzer, Matthew B; Fice, Jason B; Cronin, Duane S

    2011-11-01

    Predicting neck response and injury resulting from motor vehicle accidents is essential to improving occupant protection. A detailed human cervical spine finite element model has been developed, with material properties and geometry determined a priori of any validation, for the evaluation of global kinematics and tissue-level response. Model validation was based on flexion/extension response at the segment level, tension response of the whole ligamentous cervical spine, head kinematic response from volunteer frontal impacts, and soft tissue response from cadaveric whole cervical spine frontal impacts. The validation responses were rated as 0.79, assessed using advanced cross-correlation analysis, indicating the model exhibits good biofidelity. The model was then used to evaluate soft tissue response in frontal impact scenarios ranging from 8G to 22G in severity. Disc strains were highest in the C4-C5-C6 segments, and ligament strains were greatest in the ISL and LF ligaments. Both ligament and disc fiber strain levels exceeded the failure tolerances in the 22G case, in agreement with existing data. This study demonstrated that a cervical spine model can be developed at the tissue level and provide accurate biofidelic kinematic and local tissue response, leading to injury prediction in automotive crash scenarios. PMID:21665513

  16. Posttraumatic Growth After Motor Vehicle Crashes.

    Science.gov (United States)

    Wu, Kitty K; Leung, Patrick W L; Cho, Valda W; Law, Lawrence S C

    2016-06-01

    The relationship between sub-dimensions of posttraumatic growth (PTG) and distress was investigated for survivors of motor vehicle crashes (MVC). PTG and symptoms of posttraumatic stress disorder (PTSD) for 1045 MVC survivors who attended the Accident and Emergency Services were examined with the Chinese versions of the Posttraumatic Growth Inventory (PTGI) and the Impact of Event Scale-Revised 1 week after the experience of a MVC. A factor structure, which was different from both the original English version of the PTGI and the Chinese version of PTGI for cancer survivors, was identified. Factors extracted were: (1) Life and Self Appreciation; (2) New Commitments; (3) Enlightenment; and (4) Relating to Others. However, correlation analyses indicated a functional similarity between factors from this study and those from previous studies. Relations between PTG sub-dimensions and PTSD symptoms were identified. Results from hierarchical multiple regression analysis and structural equation modeling show that there were different predictors for different PTG sub-dimensions. Findings suggest that different modes of relationship between PTSD symptoms and PTG sub-dimensions may co-exist. PMID:27040687

  17. Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH-1 and CRASH-2 clinical trials

    Directory of Open Access Journals (Sweden)

    Roberts Ian

    2011-02-01

    Full Text Available Abstract Background All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. Methods We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials, quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. Results The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions, whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions. Conclusions Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. Trial Registration Numbers CRASH-1: ISRCTN74459797 CRASH-2: ISRCTN86750102

  18. Spatial regression analysis of traffic crashes in Seoul.

    Science.gov (United States)

    Rhee, Kyoung-Ah; Kim, Joon-Ki; Lee, Young-Ihn; Ulfarsson, Gudmundur F

    2016-06-01

    Traffic crashes can be spatially correlated events and the analysis of the distribution of traffic crash frequency requires evaluation of parameters that reflect spatial properties and correlation. Typically this spatial aspect of crash data is not used in everyday practice by planning agencies and this contributes to a gap between research and practice. A database of traffic crashes in Seoul, Korea, in 2010 was developed at the traffic analysis zone (TAZ) level with a number of GIS developed spatial variables. Practical spatial models using available software were estimated. The spatial error model was determined to be better than the spatial lag model and an ordinary least squares baseline regression. A geographically weighted regression model provided useful insights about localization of effects. The results found that an increased length of roads with speed limit below 30km/h and a higher ratio of residents below age of 15 were correlated with lower traffic crash frequency, while a higher ratio of residents who moved to the TAZ, more vehicle-kilometers traveled, and a greater number of access points with speed limit difference between side roads and mainline above 30km/h all increased the number of traffic crashes. This suggests, for example, that better control or design for merging lower speed roads with higher speed roads is important. A key result is that the length of bus-only center lanes had the largest effect on increasing traffic crashes. This is important as bus-only center lanes with bus stop islands have been increasingly used to improve transit times. Hence the potential negative safety impacts of such systems need to be studied further and mitigated through improved design of pedestrian access to center bus stop islands. PMID:26994374

  19. Modelling the hierarchical structure of road crash data : application to severity analysis

    OpenAIRE

    Lenguerrand, E.; MARTIN,JL; Laumon, B.

    2006-01-01

    Road crashes have an unquestionably hierarchical crash-car-occupant structure. Multilevel models are used with correlated data, but their application to crash data can be difficult. The number of sub-clusters per cluster is small, with less than two cars per crash and less than two occupants per car, whereas the number of clusters can be high, with several hundred/thousand crashes. Application of the Monte-Carlo method on observed and simulated French road crash data between 1996 and 2000 all...

  20. The tole of towing services at motor vehicle crashes.

    Science.gov (United States)

    Dean, L; Jame, W; Ryan, G A

    1975-08-16

    A survey of tow truck services operating in a defined area of the south-east suburbs of Melbourne was undertaken to determine their potential for delivering emergency medical care at the scene of crashes. Most towing firms have an association with a panel-beating shop, and operate within a limited area of one to three miles radius. The rapid response of tow trucks to crash scenes is due to their well-developed intelligence network of "spotters" and the short distances the trucks travel. Very little first aid is provided by the drivers, although one-fifth had some first aid training at some time. In about one-half of the calls to crashes a damaged vehicle is still at the scene, in about 20% an ambulance is called, and in about 5% a hospital admission occurs. Direct observation of 22 crashes suggests that on average, tow trucks arrive at a crash scene five minutes before the ambulance, and fifteen minutes before the police. There is a good case for making first aid training a preerequisite for issue of a tow truck operator's license. PMID:1160789

  1. Urban sprawl as a risk factor in motor vehicle crashes

    Science.gov (United States)

    Ewing, Reid; Hamidi, Shima; Grace, James B.

    2016-01-01

    A decade ago, compactness/sprawl indices were developed for metropolitan areas and counties which have been widely used in health and other research. In this study, we first update the original county index to 2010, then develop a refined index that accounts for more relevant factors, and finally seek to test the relationship between sprawl and traffic crash rates using structural equation modelling. Controlling for covariates, we find that sprawl is associated with significantly higher direct and indirect effects on fatal crash rates. The direct effect is likely due to the higher traffic speeds in sprawling areas, and the indirect effect is due to greater vehicle miles driven in such areas. Conversely, sprawl has negative direct relationships with total crashes and non-fatal injury crashes, and these offset (and sometimes overwhelm) the positive indirect effects of sprawl on both types of crashes through the mediating effect of increased vehicle miles driven. The most likely explanation is the greater prevalence of fender benders and other minor accidents in the low speed, high conflict traffic environments of compact areas, negating the lower vehicle miles travelled per capita in such areas.

  2. Delamination Modeling of Composites for Improved Crash Analysis

    Science.gov (United States)

    Fleming, David C.

    1999-01-01

    Finite element crash modeling of composite structures is limited by the inability of current commercial crash codes to accurately model delamination growth. Efforts are made to implement and assess delamination modeling techniques using a current finite element crash code, MSC/DYTRAN. Three methods are evaluated, including a straightforward method based on monitoring forces in elements or constraints representing an interface; a cohesive fracture model proposed in the literature; and the virtual crack closure technique commonly used in fracture mechanics. Results are compared with dynamic double cantilever beam test data from the literature. Examples show that it is possible to accurately model delamination propagation in this case. However, the computational demands required for accurate solution are great and reliable property data may not be available to support general crash modeling efforts. Additional examples are modeled including an impact-loaded beam, damage initiation in laminated crushing specimens, and a scaled aircraft subfloor structures in which composite sandwich structures are used as energy-absorbing elements. These examples illustrate some of the difficulties in modeling delamination as part of a finite element crash analysis.

  3. A crash programme scenario for the Canadian oil sands industry

    International Nuclear Information System (INIS)

    The report Peaking of World Oil Production: Impacts, Mitigation and Risk Management, by Robert L. Hirsch et al., concludes that Peak Oil is going to happen and that worldwide large-scale mitigation efforts are necessary to avoid its possible devastating effects for the world economy. These efforts include accelerated production, referred to as crash programme production, from Canada's oil sands. The objective of this article is to investigate and analyse what production levels that might be reasonable to expect from a crash programme for the Canadian oil sands industry, within the time frame 2006-2018 and 2006-2050. The implementation of a crash programme for the Canadian oil sands industry is associated with serious difficulties. There is not a large enough supply of natural gas to support a future Canadian oil sands industry with today's dependence on natural gas. It is possible to use bitumen as fuel and for upgrading, although it seems to be incompatible with Canada's obligations under the Kyoto treaty. For practical long-term high production, Canada must construct nuclear facilities to generate energy for the in situ projects. Even in a very optimistic scenario Canada's oil sands will not prevent Peak Oil. A short-term crash programme from the Canadian oil sands industry achieves about 3.6 mb/d by 2018. A long-term crash programme results in a production of approximately 5 mb/d by 2030

  4. Human fatigue and the crash of the airship Italia

    Directory of Open Access Journals (Sweden)

    Gregg A. Bendrick

    2016-07-01

    Full Text Available The airship Italia, commanded by General Umberto Nobile, crashed during its return flight from the North Pole in 1928. The cause of the accident was never satisfactorily explained. We present evidence that the crash may have been fatigue-related. Nobile's memoirs indicate that at the time of the crash he had been awake for at least 72 h. Sleep deprivation impairs multiple aspects of cognitive functioning necessary for exploration missions. Just prior to the crash, Nobile made three command errors, all of which are of types associated with inadequate sleep. First, he ordered a release of lift gas when he should have restarted engines (an example of incorrect data synthesis, with deterioration of divergent thinking; second, he inappropriately ordered the ship above the cloud layer (a deficiency in the assessment of relative risks; and third, he remained above the cloud layer for a prolonged period of time (examples of attention to secondary problems, and calculation problems. We argue that as a result of these three errors, which would not be expected from such an experienced commander, there was no longer enough static lift to maintain level flight when the ship went below the cloud layer. Applying Circadian Performance Simulation Software to the sleep–wake patterns described by Nobile in his memoirs, we found that the predicted performance for someone awake as long as he had been is extremely low. This supports the historical evidence that human fatigue contributed to the crash of the Italia.

  5. Mapping Bicycle Crash Risk Patterns on the Local Scale

    Directory of Open Access Journals (Sweden)

    Martin Loidl

    2016-09-01

    Full Text Available Currently, mainly aggregated statistics are used for bicycle crash risk calculations. Thus, the understanding of spatial patterns at local scale levels remains vague. Using an agent-based flow model and a bicycle crash database covering 10 continuous years of observation allows us to calculate and map the crash risk on various spatial scales for the city of Salzburg (Austria. In doing so, we directly account for the spatial heterogeneity of crash occurrences. Additionally, we provide a measure for the statistical robustness on the level of single reference units and consider modifiable areal unit problem (MAUP effects in our analysis. This study is the first of its kind. The results facilitate a better understanding of spatial patterns of bicycle crash rates on the local scale. This is especially important for cities that strive to improve the safety situation for bicyclists in order to address prevailing safety concerns that keep people from using the bicycle as a utilitarian mode of (urban transport.

  6. Option pricing during post-crash relaxation times

    Science.gov (United States)

    Dibeh, Ghassan; Harmanani, Haidar M.

    2007-07-01

    This paper presents a model for option pricing in markets that experience financial crashes. The stochastic differential equation (SDE) of stock price dynamics is coupled to a post-crash market index. The resultant SDE is shown to have stock price and time dependent volatility. The partial differential equation (PDE) for call prices is derived using risk-neutral pricing. European call prices are then estimated using Monte Carlo and finite difference methods. Results of the model show that call option prices after the crash are systematically less than those predicted by the Black-Scholes model. This is a result of the effect of non-constant volatility of the model that causes a volatility skew.

  7. Estimating national road crash fatalities using aggregate data.

    Science.gov (United States)

    Ahmed, Anwaar; Khan, Beenish Akbar; Khurshid, Muhammad Bilal; Khan, Muhammad Babar; Waheed, Abdul

    2016-09-01

    Injuries and fatalities from road traffic crashes have emerged a major public health challenge in Pakistan. Reliable estimates of road crash fatalities (RCF) of a country, is a vital element needed for identification and control of key risk factors, road-safety improvement efforts and prioritizing national health. Reliability of current annual RCF estimates for Pakistan becomes highly questionable due to serious underreporting. This study aimed to predict annual RCF for Pakistan using data from World Health Organization and International Road Federation sources. An ordinary least square (OLS) regression model that relates fatality rate with different explanatory variables was developed. RCF were predicted for Pakistan for year 2012 and 2013, and results were compared with national police reported estimates. Study results indicated that there is serious underreporting of RCF in Pakistan and immediate measures are needed to improve the existing road crash recording and reporting system at the national and subnational levels. PMID:25571957

  8. Car Crash Risk May Nearly Double in People Prone to Fainting

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_157512.html Car Crash Risk May Nearly Double in People Prone to ... as likely as others to get into a car crash, a new study finds. The researchers say the ...

  9. Drowsiness, counter-measures to drowsiness, and the risk of a motor vehicle crash

    OpenAIRE

    Cummings, P; Koepsell, T; Moffat, J; Rivara, F

    2001-01-01

    Objectives—Knowledge of how different indicators of drowsiness affect crash risk might be useful to drivers. This study sought to estimate how drowsiness related factors, and factors that might counteract drowsiness, are related to the risk of a crash.

  10. Crash Risk Soars When Truck Drivers Don't Treat Sleep Apnea

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_157882.html Crash Risk Soars When Truck Drivers Don't Treat ... their treatment program are much more likely to crash, a new study finds. "The most surprising result ...

  11. Pot-Linked Fatal Car Crashes Doubled in One State After Legalization

    Science.gov (United States)

    ... news/fullstory_158760.html Pot-Linked Fatal Car Crashes Doubled in One State After Legalization Experts say ... 2016 (HealthDay News) -- The number of fatal car crashes involving marijuana more than doubled after Washington state ...

  12. A different perspective on conspicuity related motorcycle crashes.

    Science.gov (United States)

    de Craen, Saskia; Doumen, Michelle J A; van Norden, Yvette

    2014-02-01

    The most common type of conflict in which a motorcyclist is injured or killed is a collision between a motorcycle and a car, often in priority situations. Many studies on motorcycle safety focus on the question why car drivers fail to give priority and on the poor conspicuity of motorcycles. The concept of 'looked-but-failed-to-see' crashes is a recurring item. On the other hand, it is not entirely unexpected that motorcycles have many conflicts with cars; there simply are so many cars on the road. This paper tries to unravel whether - acknowledging the differences in exposure - car drivers indeed fail to yield for motorcycles more often than for other cars. For this purpose we compared the causes of crashes on intersections (e.g. failing to give priority, speeding, etc.) between different crash types (car-motorcycle or car-car). In addition, we compared the crash causes of dual drivers (i.e. car drivers who also have their motorcycle licence) with regular car drivers. Our crash analysis suggests that car drivers do not fail to give priority to motorcycles relatively more often than to another car when this car/motorcycle approaches from a perpendicular angle. There is only one priority situation where motorcycles seem to be at a disadvantage compared to cars. This is when a car makes a left turn, and fails to give priority to an oncoming motorcycle. This specific crash scenario occurs more often when the oncoming vehicle is a motorcycle than when it is a car. We did not find a significant difference between dual drivers and regular car drivers in how often they give priority to motorcycles compared to cars. PMID:24291070

  13. Modeling crash spatial heterogeneity: random parameter versus geographically weighting.

    Science.gov (United States)

    Xu, Pengpeng; Huang, Helai

    2015-02-01

    The widely adopted techniques for regional crash modeling include the negative binomial model (NB) and Bayesian negative binomial model with conditional autoregressive prior (CAR). The outputs from both models consist of a set of fixed global parameter estimates. However, the impacts of predicting variables on crash counts might not be stationary over space. This study intended to quantitatively investigate this spatial heterogeneity in regional safety modeling using two advanced approaches, i.e., random parameter negative binomial model (RPNB) and semi-parametric geographically weighted Poisson regression model (S-GWPR). Based on a 3-year data set from the county of Hillsborough, Florida, results revealed that (1) both RPNB and S-GWPR successfully capture the spatially varying relationship, but the two methods yield notably different sets of results; (2) the S-GWPR performs best with the highest value of Rd(2) as well as the lowest mean absolute deviance and Akaike information criterion measures. Whereas the RPNB is comparable to the CAR, in some cases, it provides less accurate predictions; (3) a moderately significant spatial correlation is found in the residuals of RPNB and NB, implying the inadequacy in accounting for the spatial correlation existed across adjacent zones. As crash data are typically collected with reference to location dimension, it is desirable to firstly make use of the geographical component to explore explicitly spatial aspects of the crash data (i.e., the spatial heterogeneity, or the spatially structured varying relationships), then is the unobserved heterogeneity by non-spatial or fuzzy techniques. The S-GWPR is proven to be more appropriate for regional crash modeling as the method outperforms the global models in capturing the spatial heterogeneity occurring in the relationship that is model, and compared with the non-spatial model, it is capable of accounting for the spatial correlation in crash data. PMID:25460087

  14. Cyclists and drivers in road interactions: A comparison of perceived crash risk

    OpenAIRE

    CHAURAND, Nadine; Delhomme, Patricia

    2013-01-01

    Today’s increase in the number of cyclists has triggered a change in the interactions to be handled by road users. However, few studies have investigated crash risk perceived by cyclists interacting with other users, and few have compared cyclists’ and drivers’ perceptions of crash risk in bike–car interactions,the most dangerous situation for cyclists. Our aims here are to study perceived crash risk (no matter the seriousness of the crash) in six common road situation...

  15. Accident analysis for aircraft crash into hazardous facilities: DOE standard

    International Nuclear Information System (INIS)

    This standard provides the user with sufficient information to evaluate and assess the significance of aircraft crash risk on facility safety without expending excessive effort where it is not required. It establishes an approach for performing a conservative analysis of the risk posed by a release of hazardous radioactive or chemical material resulting from an aircraft crash into a facility containing significant quantities of such material. This can establish whether a facility has a significant potential for an aircraft impact and whether this has the potential for producing significant offsite or onsite consequences. General implementation guidance, screening and evaluation guidelines, and methodologies for the evaluations are included

  16. 78 FR 53386 - Federal Motor Vehicle Safety Standards; Occupant Crash Protection

    Science.gov (United States)

    2013-08-29

    ... 20 mph to 25 mph rigid barrier crash test (65 FR 30680). \\11\\ On September 2, 1993, NHTSA amended... considering unbelted crash test requirements date back to the 1970s (35 FR 16927).\\14\\ To do so without a...; Occupant Crash Protection AGENCY: National Highway Traffic Safety Administration (NHTSA), DOT....

  17. Two-fractal overlap time series: Earthquakes and market crashes

    Indian Academy of Sciences (India)

    Bikas K Chakrabarti; Arnab Chatterjee; Pratip Bhattacharyya

    2008-08-01

    We find prominent similarities in the features of the time series for the (model earthquakes or) overlap of two Cantor sets when one set moves with uniform relative velocity over the other and time series of stock prices. An anticipation method for some of the crashes have been proposed here, based on these observations.

  18. Car-Crash Experiment for the Undergraduate Laboratory

    Science.gov (United States)

    Ball, Penny L.; And Others

    1974-01-01

    Describes an interesting, inexpensive, and highly motivating experiment to study uniform and accelerated motion by measuring the position of a car as it crashes into a rigid wall. Data are obtained from a sequence of pictures made by a high speed camera. (Author/SLH)

  19. Crash simulations of wheelchair-occupant systems in transport.

    Science.gov (United States)

    Kang, W; Pilkey, W D

    1998-01-01

    A nonlinear multirigid body dynamic computer model has been developed to simulate the dynamic responses of a wheelchair-occupant system in a vehicle during a crash. The occupant, restrained by safety belts, is seated in a wheelchair that is, in turn, tied down in a vehicle. Validated extensively by crash sled tests at three laboratories, this model has been used to predict the responses of wheelchair-occupant systems in various crash environments. To evaluate the crashworthiness of different wheelchair tie-downs, the sensitivity of several design parameters, such as tiedown stiffness, wheel stiffness, and tiedown positions, has been studied using this model, and optimal values of these parameters for the wheelchair-occupant system have been obtained. Moreover, the model has been used to study the sensitivity of crash sled test pulse corridors in an effort to develop a sled test standard. It has been found that an existing ISO corridor allows large variation and should be "tightened." The model was implemented using a version of the multibody dynamic simulator, the Articulated Total Body program. PMID:9505255

  20. Finite pressure effects on the tokamak sawtooth crash

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Yasutaro

    1998-07-01

    The sawtooth crash is a hazardous, disruptive phenomenon that is observed in tokamaks whenever the safety factor at the magnetic axis is below unity. Recently, Tokamak Test Fusion Reactor (TFTR) experimental data has revealed interesting features of the dynamical pressure evolution during the crash phase. Motivated by the experimental results, this dissertation focuses on theoretical modeling of the finite pressure effects on the nonlinear stage of the sawtooth crash. The crash phase has been studied numerically employed a toroidal magnetohydrodynamic (MHD) initial value code deduced from the FAR code. For the first time, by starting from a concentric equilibrium, it has been shown that the evolution through an m/n = 1/1 magnetic island induces secondary high-n ballooning instabilities. The magnetic island evolution gives rise to convection of the pressure inside the inversion radius and builds up a steep pressure gradient across the island separatrix, or current sheet, and thereby triggers ballooning instabilities below the threshold for the axisymmetric equilibrium. Due to the onset of secondary ballooning modes, concomitant fine scale vortices and magnetic stochasticity are generated. These effects produce strong flows across the current sheet, and thereby significant modify the m = 1 driven magnetic reconnection process. The resultant interaction of the high-n ballooning modes with the magnetic reconnection process is discussed.

  1. Finite pressure effects on the tokamak sawtooth crash

    International Nuclear Information System (INIS)

    The sawtooth crash is a hazardous, disruptive phenomenon that is observed in tokamaks whenever the safety factor at the magnetic axis is below unity. Recently, Tokamak Test Fusion Reactor (TFTR) experimental data has revealed interesting features of the dynamical pressure evolution during the crash phase. Motivated by the experimental results, this dissertation focuses on theoretical modeling of the finite pressure effects on the nonlinear stage of the sawtooth crash. The crash phase has been studied numerically employed a toroidal magnetohydrodynamic (MHD) initial value code deduced from the FAR code. For the first time, by starting from a concentric equilibrium, it has been shown that the evolution through an m/n = 1/1 magnetic island induces secondary high-n ballooning instabilities. The magnetic island evolution gives rise to convection of the pressure inside the inversion radius and builds up a steep pressure gradient across the island separatrix, or current sheet, and thereby triggers ballooning instabilities below the threshold for the axisymmetric equilibrium. Due to the onset of secondary ballooning modes, concomitant fine scale vortices and magnetic stochasticity are generated. These effects produce strong flows across the current sheet, and thereby significant modify the m = 1 driven magnetic reconnection process. The resultant interaction of the high-n ballooning modes with the magnetic reconnection process is discussed

  2. An orthotropic damage model for crash simulation of composites

    NARCIS (Netherlands)

    Wang, W.; Swartjes, F.H.M.; Gan, M.D.

    2006-01-01

    In this paper, a practical orthotropic damage model is developed and tested for composite materials during crash. The model uses the Hashin's failure criteria in which the fibre and matrix failures are described explicitly, both in tension and compression. A linear softening degradation is proposed

  3. Exploring older driver crash trend: New Jersey case study

    Directory of Open Access Journals (Sweden)

    Vanvi Trieu

    2014-04-01

    Full Text Available Older drivers age 65 and above are known to experience greater risk on the roadway as well as increasing the risk to other roadway users. Within the next 20 years, their population is expected to increase from 41 million in 2011 to 70 million in 2030. To address this foreseeable change, the nation's recent Moving Ahead for Progress in the 21st Century (MAP-21 act requires state and local governments to examine older drivers and pedestrian risks and implement countermeasures as appropriate. This research was conducted to assist agencies in strategising for future plans, programmes and initiatives to better address the problem presented. This was accomplished by performing a detailed engineering analysis on crash data of older drivers over a 10-year period (2003–2012 from the state of New Jersey to identify crash trends and characteristics. A major finding from this research was the increase in fatal crashes of older drivers as a function of age. Top-ranking collision types with other vehicles and non-vehicles were identified. Crashes as a function of seasonal change, climate and lighting conditions were also examined.

  4. Two Fractal Overlap Time Series: Earthquakes and Market Crashes

    OpenAIRE

    Chakrabarti, Bikas K.; Arnab Chatterjee; Pratip Bhattacharyya

    2007-01-01

    We find prominent similarities in the features of the time series for the (model earthquakes or) overlap of two Cantor sets when one set moves with uniform relative velocity over the other and time series of stock prices. An anticipation method for some of the crashes have been proposed here, based on these observations.

  5. Investigation of work zone crash casualty patterns using association rules.

    Science.gov (United States)

    Weng, Jinxian; Zhu, Jia-Zheng; Yan, Xuedong; Liu, Zhiyuan

    2016-07-01

    Investigation of the casualty crash characteristics and contributory factors is one of the high-priority issues in traffic safety analysis. In this paper, we propose a method based on association rules to analyze the characteristics and contributory factors of work zone crash casualties. A case study is conducted using the Michigan M-94/I-94/I-94BL/I-94BR work zone crash data from 2004 to 2008. The obtained association rules are divided into two parts including rules with high-lift, and rules with high-support for the further analysis. The results show that almost all the high-lift rules contain either environmental or occupant characteristics. The majority of association rules are centered on specific characteristics, such as drinking driving, the highway with more than 4 lanes, speed-limit over 40mph and not use of traffic control devices. It should be pointed out that some stronger associated rules were found in the high-support part. With the network visualization, the association rule method can provide more understandable results for investigating the patterns of work zone crash casualties. PMID:27038500

  6. On rank 4 projective planes

    OpenAIRE

    Bachmann, O.

    1981-01-01

    Let a finite projective plane be called rank m plane if it admits a collineation group G of rank m, let it be called strong rank m plane if moreover GP=G1 for some point-line pair (P,1). It is well known that every rank 2 plane is desarguesian (Theorem of Ostrom and Wagner). It is conjectured that the only rank 3 plane is the plane of order 2. By [1] and [7] the only strong rank 3 plane is the plane of order 2. In this paper it is proved that no strong rank 4 plane exists.

  7. Safety performance functions for crash severity on undivided rural roads.

    Science.gov (United States)

    Russo, Francesca; Busiello, Mariarosaria; Dell'Acqua, Gianluca

    2016-08-01

    The objective of this paper is to explore the effect of the road features of two-lane rural road networks on crash severity. One of the main goals is to calibrate Safety Performance Functions (SPFs) that can predict the frequency per year of injuries and fatalities on homogeneous road segments. It was found that on more than 2000km of study-road network that annual average daily traffic, lane width, curvature change rate, length, and vertical grade are important variables in explaining the severity of crashes. A crash database covering a 5-year period was examined to achieve the goals (1295 injurious crashes that included 2089 injuries and 235 fatalities). A total of 1000km were used to calibrate SPFs and the remaining 1000km reflecting the traffic, geometric, functional features of the preceding one were used to validate their effectiveness. A negative binomial regression model was used. Reflecting the crash configurations of the dataset and maximizing the validation outcomes, four main sets of SPFs were developed as follows: (a) one equation to predict only injury frequency per year for the subset where only non-fatal injuries occurred, (b) two different equations to predict injury frequency and fatality frequency per year per sub-set where at least one fa tality occurred together with one injury, and (c) only one equation to predict the total frequency per year of total casualties correlating accurate percentages to obtain the final expected frequency of injuries and fatalities per year on homogeneous road segments. Residual analysis confirms the effectiveness of the SPFs. PMID:27177393

  8. Activity modes selection for project crashing through deterministic simulation

    Directory of Open Access Journals (Sweden)

    Ashok Mohanty

    2011-12-01

    Full Text Available Purpose: The time-cost trade-off problem addressed by CPM-based analytical approaches, assume unlimited resources and the existence of a continuous time-cost function. However, given the discrete nature of most resources, the activities can often be crashed only stepwise. Activity crashing for discrete time-cost function is also known as the activity modes selection problem in the project management. This problem is known to be NP-hard. Sophisticated optimization techniques such as Dynamic Programming, Integer Programming, Genetic Algorithm, Ant Colony Optimization have been used for finding efficient solution to activity modes selection problem. The paper presents a simple method that can provide efficient solution to activity modes selection problem for project crashing.Design/methodology/approach: Simulation based method implemented on electronic spreadsheet to determine activity modes for project crashing. The method is illustrated with the help of an example.Findings: The paper shows that a simple approach based on simple heuristic and deterministic simulation can give good result comparable to sophisticated optimization techniques.Research limitations/implications: The simulation based crashing method presented in this paper is developed to return satisfactory solutions but not necessarily an optimal solution.Practical implications: The use of spreadsheets for solving the Management Science and Operations Research problems make the techniques more accessible to practitioners. Spreadsheets provide a natural interface for model building, are easy to use in terms of inputs, solutions and report generation, and allow users to perform what-if analysis.Originality/value: The paper presents the application of simulation implemented on a spreadsheet to determine efficient solution to discrete time cost tradeoff problem.

  9. The Impact of Driver Inattention on Near-Crash/Crash Risk: An Analysis Using the 100-Car Naturalistic Driving Study Data

    OpenAIRE

    Klauer, Sheila G; Dingus, Thomas A.; Neale, Vicki L.; Sudweeks, Jeremy D.; Ramsey, D J

    2006-01-01

    The purpose of this report was to conduct in-depth analyses of driver inattention using the driving data collected in the 100-Car Naturalistic Driving Study. An additional database of baseline epochs was reduced from the raw data and used in conjunction with the crash and near-crash data identified as part of the original 100-Car Study to account for exposure and establish near-crash/crash risk. The analyses presented in this report are able to establish direct relationships between driving b...

  10. 78 FR 13756 - Technical Report: Effectiveness of LED Stop Lamps for Reducing Rear-End Crashes: Analyses of...

    Science.gov (United States)

    2013-02-28

    ... Reducing Rear-End Crashes: Analyses of State Crash Data AGENCY: National Highway Traffic Safety.... The report's title is: Effectiveness of LED Stop Lamps for Reducing Rear-End Crashes: Analyses of State Crash Data. DATES: Comments must be received no later than June 28, 2013. ADDRESSES: Report:...

  11. Influence of the strain path on crash properties of a crash-box structure by experimental and numerical approaches

    Science.gov (United States)

    Durrenberger, L.; Even, D.; Molinari, A.; Rusinek, A.

    2006-08-01

    In order to reduce the gas emission without decreasing the passengers safety, the UHSS (Ultra High Strength Steel) steels are more and more used in the automotive industry. The very high mechanical characteristics of these steels allow to reduce the car weight thanks to the thickness reduction of the structure parts. The aim of this study is to analyse the plastic pre-strain effect (forming) on the crash properties of a crash-box structure. In order to achieve this goal, experimental rheological tests have been performed by combining quasi-static tensile tests followed by dynamic tensile test (8.10 - 3 s - 1 ≤ dot{\\varepsilon} ≤ 1000 s - 1) for a TRIP steel produced by ARCELOR. The combination of these results allows to obtain a better understanding of the steel behaviour in dynamic loading under different strain paths. All these information are necessary for an efficient simulation of crash test by including a pertinent material response. A special attention is given to the influence of the previous forming process on the dynamical response of crash boxes.

  12. Nonlinear analysis of commercial aircraft impact on a reactor building—Comparison between integral and decoupled crash simulation

    International Nuclear Information System (INIS)

    Since 9/11, the crash of a commercial aeroplane on the reactor building of a nuclear power plant is a realistic design scenario. Before that the structural behaviour under a crash of a military plane was investigated by a procedure using load-time functions (Riera, 1968). Thereby, the computation of the load-time-function was based on a conceptional model considering the main stiffness parts and masses by discrete elements. With respect to the homogeneous structural set-up of a military plane, the application of this model and the derived load-time-function applied as lumped load case seems very feasible. Contrary thereto the structural set-up of a commercial aeroplane, with e.g. the high mass concentration of the turbine or the high stiffness of the wing box compared to other parts, is different. This can be counteracted by using a more detailed finite element (FE) model for the computation of the load-time-function and by dividing the load case for the reactor building in different main load zones. Although this represents a more detailed investigation, the procedure of using a load-time-function still has the disadvantage to separate the real scenario into two steps. Thereby, the direct interaction between the structure and the aeroplane including all softening effects due to material respectively structural compliances is neglected. This leads to the general conclusion that by applying load-time-functions the results are conservative compared to the real behaviour. Due to the increased capabilities of numerical software solutions it is also possible nowadays to carry out integral crash simulations, combining all effects within one simulation. Compared to the procedure of using load-time-functions, the numerical complexity and therefore the amount of work for this integral method are increased. Within this paper both procedures (load-time function by detailed FE-model and the integral method) are exemplarily compared to each other by a crash analysis of an

  13. Co-Movements Of U.S. And European Stock Markets Before And After The 2008 Gloal Stock Market Crash

    OpenAIRE

    Meric Ilhan; Nygren Lan Ma; Bentley Jerome T.; McCall Charles W.

    2015-01-01

    Empirical studies show that correlation between national stock markets increased and the benefits of global portfolio diversification decreased significantly after the global stock market crash of 1987. The 1987 and 2008 crashes are the two most important global stock market crashes since the 1929 Great depression. Although the effects of the 1987 crash on the comovements of national stock markets have been investigated extensively, the effects of the 2008 crash have not been studied sufficie...

  14. Social costs of road crashes: An international analysis.

    Science.gov (United States)

    Wijnen, Wim; Stipdonk, Henk

    2016-09-01

    This paper provides an international overview of the most recent estimates of the social costs of road crashes: total costs, value per casualty and breakdown in cost components. The analysis is based on publications about the national costs of road crashes of 17 countries, of which ten high income countries (HICs) and seven low and middle income countries (LMICs). Costs are expressed as a proportion of the gross domestic product (GDP). Differences between countries are described and explained. These are partly a consequence of differences in the road safety level, but there are also methodological explanations. Countries may or may not correct for underreporting of road crashes, they may or may not use the internationally recommended willingness to pay (WTP)-method for estimating human costs, and there are methodological differences regarding the calculation of some other cost components. The analysis shows that the social costs of road crashes in HICs range from 0.5% to 6.0% of the GDP with an average of 2.7%. Excluding countries that do not use a WTP- method for estimating human costs and countries that do not correct for underreporting, results in average costs of 3.3% of GDP. For LMICs that do correct for underreporting the share in GDP ranges from 1.1% to 2.9%. However, none of the LMICs included has performed a WTP study of the human costs. A major part of the costs is related to injuries: an average share of 50% for both HICs and LMICs. The average share of fatalities in the costs is 23% and 30% respectively. Prevention of injuries is thus important to bring down the socio-economic burden of road crashes. The paper shows that there are methodological differences between countries regarding cost components that are taken into account and regarding the methods used to estimate specific cost components. In order to be able to make sound comparisons of the costs of road crashes across countries, (further) harmonization of cost studies is recommended. This can be

  15. Motor vehicle crash-related subdural hematoma from real-world head impact data.

    Science.gov (United States)

    Urban, Jillian E; Whitlow, Christopher T; Edgerton, Colston A; Powers, Alexander K; Maldjian, Joseph A; Stitzel, Joel D

    2012-12-10

    Abstract Approximately 1,700,000 people sustain a traumatic brain injury (TBI) each year and motor vehicle crashes (MVCs) are a leading cause of hospitalization from TBI. Acute subdural hematoma (SDH) is a common intracranial injury that occurs in MVCs associated with high mortality and morbidity rates. In this study, SDH volume and midline shift have been analyzed in order to better understand occupant injury by correlating them to crash and occupant parameters. Fifty-seven head computed tomography (CT) scans were selected from the Crash Injury Research Engineering Network (CIREN) with Abbreviated Injury Scale (AIS) level 3+ SDH. Semi-automated methods were used to isolate the intracranial volume. SDH and additional occupant intracranial injuries were segmented across axial CT images, providing a total SDH injury volume. SDH volume was correlated to crash parameters and occupant characteristics. Results show a positive correlation between SDH volume and crash severity in near-side and frontal crashes. Additionally, the location of the resulting hemorrhage varied by crash type. Those with greater SDH volumes had significantly lower Glasgow Coma Scale (GCS) scores at the crash site in near-side crashes. Age and fracture type were found to be significant contributors to SDH volume. This study is a volumetric analysis of real world brain injuries and known MVC impacts. The results of this study demonstrate a relationship among SDH volume, crash mechanics, and occupant characteristics that provide a better understanding of the injury mechanisms of MVC-associated TBI. PMID:22928543

  16. Investigating driver injury severity patterns in rollover crashes using support vector machine models.

    Science.gov (United States)

    Chen, Cong; Zhang, Guohui; Qian, Zhen; Tarefder, Rafiqul A; Tian, Zong

    2016-05-01

    Rollover crash is one of the major types of traffic crashes that induce fatal injuries. It is important to investigate the factors that affect rollover crashes and their influence on driver injury severity outcomes. This study employs support vector machine (SVM) models to investigate driver injury severity patterns in rollover crashes based on two-year crash data gathered in New Mexico. The impacts of various explanatory variables are examined in terms of crash and environmental information, vehicle features, and driver demographics and behavior characteristics. A classification and regression tree (CART) model is utilized to identify significant variables and SVM models with polynomial and Gaussian radius basis function (RBF) kernels are used for model performance evaluation. It is shown that the SVM models produce reasonable prediction performance and the polynomial kernel outperforms the Gaussian RBF kernel. Variable impact analysis reveals that factors including comfortable driving environment conditions, driver alcohol or drug involvement, seatbelt use, number of travel lanes, driver demographic features, maximum vehicle damages in crashes, crash time, and crash location are significantly associated with driver incapacitating injuries and fatalities. These findings provide insights for better understanding rollover crash causes and the impacts of various explanatory factors on driver injury severity patterns. PMID:26938584

  17. Application of Probability Methods to Assess Crash Modeling Uncertainty

    Science.gov (United States)

    Lyle, Karen H.; Stockwell, Alan E.; Hardy, Robin C.

    2007-01-01

    Full-scale aircraft crash simulations performed with nonlinear, transient dynamic, finite element codes can incorporate structural complexities such as: geometrically accurate models; human occupant models; and advanced material models to include nonlinear stress-strain behaviors, and material failure. Validation of these crash simulations is difficult due to a lack of sufficient information to adequately determine the uncertainty in the experimental data and the appropriateness of modeling assumptions. This paper evaluates probabilistic approaches to quantify the effects of finite element modeling assumptions on the predicted responses. The vertical drop test of a Fokker F28 fuselage section will be the focus of this paper. The results of a probabilistic analysis using finite element simulations will be compared with experimental data.

  18. Response of equipment in nuclear power plants to airplane crash

    International Nuclear Information System (INIS)

    Nuclear power plants in Germany are to be designed against airplane crash. Two problems arise: first, the local problem of penetration as well as local destruction of the building and secondly the airplane induced vibrations of the whole building which cause loadings for secondary systems (equipment). This paper deals especially with the second problem. Floor response spectra due to airplane crash are presented for two different power plant buildings. The influence of various parameters (time history of excitation, direction and location of impact, mathematical model, soil, damping, etc.) are discussed. A comparison with the results of earthquake loading is given. Suggestions are made for developing suitable floor design spectra and using them to analyse multidegree-of-freedom systems. However, the paper gives only a partial answer to the questions arising because of some important restrictions which had to be made. Studies concerning these restrictions are still being conducted and will be presented in a separate paper. (Auth.)

  19. Response of equipment in nuclear power plants to airplane crash

    International Nuclear Information System (INIS)

    The question has been posed concerning the effect of airplane crash on the safety of the equipment (pipes, vessels, etc.) mounted on the floors and walls inside the outer structure. This equipment is set into vibration by the crash-induced shaking of the outer building; the resulting stresses may be quite appreciable. The following questions arise: a) how large are these stresses. Can they, for example, be larger than the stresses produced by earthquake loading. b) What are the significant response parameters. c) Which methods of analysis and design criteria are reasonable. To what extent is it possible to apply the techniques which have become generally accepted for earthquake loading. The paper presents a preliminary answer to these questions pending further work in this area. (orig./HP)

  20. Can a stochastic cusp catastrophe model explain stock market crashes?

    Czech Academy of Sciences Publication Activity Database

    Baruník, Jozef; Vošvrda, Miloslav

    2009-01-01

    Roč. 33, č. 10 (2009), s. 1824-1836. ISSN 0165-1889 R&D Projects: GA ČR GD402/09/H045; GA ČR GA402/09/0965 Grant ostatní: GAUK(CZ) 46108 Institutional research plan: CEZ:AV0Z10750506 Keywords : Stochastic cusp catastrophe * Bifurcations * Singularity * Nonlinear dynamics * Stock market crash Subject RIV: AH - Economics Impact factor: 1.097, year: 2009

  1. Fatal motorcycle crashes: a serious public health problem in Brazil

    OpenAIRE

    Carrasco Carlos; Godinho Mauricio; Berti de Azevedo Barros Marilisa; Rizoli Sandro; Fraga Gustavo

    2012-01-01

    Abstract Introduction The numbers of two-wheel vehicles are growing across the world. In comparison to other vehicles, motorcycles are cheaper and thus represent a significant part of the automobile market. Both the mobility and speed are attractive factors to those who want to use them for work or leisure. Crashes involving motorcyclists have become an important issue, especially fatal ones. Specific severe injuries are responsible for the deaths. Defining them is necessary in order to offer...

  2. Car Crashes and Central Disorders of Hypersomnolence: A French Study.

    Directory of Open Access Journals (Sweden)

    Fabio Pizza

    Full Text Available Drowsiness compromises driving ability by reducing alertness and attentiveness, and delayed reaction times. Sleep-related car crashes account for a considerable proportion of accident at the wheel. Narcolepsy type 1 (NT1, narcolepsy type 2 (NT2 and idiopathic hypersomnia (IH are rare central disorders of hypersomnolence, the most severe causes of sleepiness thus being potential dangerous conditions for both personal and public safety with increasing scientific, social, and political attention. Our main objective was to assess the frequency of recent car crashes in a large cohort of patients affected with well-defined central disorders of hypersomnolence versus subjects from the general population.We performed a cross-sectional study in French reference centres for rare hypersomnia diseases and included 527 patients and 781 healthy subjects. All participants included needed to have a driving license, information available on potential accident events during the last 5 years, and on potential confounders; thus analyses were performed on 282 cases (71 IH, 82 NT2, 129 NT1 and 470 healthy subjects.Patients reported more frequently than healthy subjects the occurrence of recent car crashes (in the previous five years, a risk that was confirmed in both treated and untreated subjects at study inclusion (Untreated, OR = 2.21 95%CI = [1.30-3.76], Treated OR = 2.04 95%CI = [1.26-3.30], as well as in all disease categories, and was modulated by subjective sleepiness level (Epworth scale and naps. Conversely, the risk of car accidents of patients treated for at least 5 years was not different to healthy subjects (OR = 1.23 95%CI = [0.56-2.69]. Main risk factors were analogous in patients and healthy subjects.Patients affected with central disorders of hypersomnolence had increased risk of recent car crashes compared to subjects from the general population, a finding potentially reversed by long-term treatment.

  3. The Great Crash and the Onset of the Great Depression

    OpenAIRE

    Christina D. Romer

    1988-01-01

    This paper argues that the collapse of stock prices in October 1929 generated temporary uncertainty about future income, which led consumers to forgo purchases of durable goods. That the Great Crash generated uncertainty is evidenced by the decline in surety expressed by contemporary forecasters. That this uncertainty affected consumer behavior is shown by the fact that spending on consumer durables declined drastically in late 1929, while spending on perishable goods rose slightly. This effe...

  4. Predictive estimates for behaviour in the train crash demonstration

    International Nuclear Information System (INIS)

    Predictive work for the Train Crash Demonstration included estimates of the post-impact behaviour of the flask, flatrol, locomotive and carriages. These estimates were produced using hand calculations and desk study of certain relevant railway incidents. Because of the natural uncertainties in the process, an event 'tree' was constructed to show the various possible motions foreseen. Observations from the Demonstration are summarised and compared with the estimates. (author)

  5. Determinants of road traffic crash fatalities across Indian States

    OpenAIRE

    Grimm, Michael; Treibich, Carole

    2012-01-01

    textabstractObjective: This paper explores the determinants of road traffic crash fatalities in India. As potential factors, the analysis considers, besides income, the sociodemographic populationstructure, motorization levels, road and health infrastructure and road rule enforcement. Methods: An original panel data set covering 25 Indian states is analyzed using multivariate regression analysis. Time and state fixed effects account for unobserved heterogeneity across states and time. Results...

  6. Liquidity, Default and Crashes: Endogenous Contracts in General Equilibrium

    OpenAIRE

    John Geanakoplos

    2001-01-01

    The possibility of default limits available liquidity. If the potential default draws nearer, a liquidity crisis may ensue, causing a crash in asset prices, even if the probability of default barely changes, and even if no defaults subsequently materialize. Introducing default and limited collateral into general equilibrium theory (GE) allows for a theory of endogenous contracts, including endogenous margin requirements on loans. This in turn allows GE to explain liquidity and liquidity crise...

  7. LESSONS IN CRISIS MISMANAGEMENT FROM THE 1929 CRASH

    OpenAIRE

    Janice M. Traflet (ed.)

    2006-01-01

    Crisis management theory illuminates the New York Stock Exchanges efforts to recover organizational legitimacy after the 1929 crash and the scandals unearthed in its wake. Ineptly defusing charges of an unfair and disorderly marketplace, NYSE President Richard Whitney and his Old Guard colleagues magnified perceptions of Exchange dysfunction. Even after New Deal reform of the securities sector the NYSE remained a self-regulatory organization. How did the NYSE emerge from its crisis decade (19...

  8. Numerical Simulation of Helicopter Cockpit Seat subjected to Crash Impact

    Directory of Open Access Journals (Sweden)

    M.N. Sulaiman

    2013-01-01

    Full Text Available Sikorsky S-61 or better known as “Nuri” had served the Malaysian aviation sector for the past four decades. It is mainly used for transportation, combat search and rescue purposes. However, there were Nuri helicopter crashes or accident cases reported during its operation period which involved loss of its occupants. The pilot survivability rate can be improved provided that the vertical impact loading on the helicopter is reduced during the crash accident. Utilization of an energy absorbing pilot seat or cockpit structure maybe one of the approaches to minimize the impact shock exerted to the occupants. However, the shock or maximum acceleration of the cockpit/pilot seat has to be first determined before a thorough design scheme can be undertaken. In this study, a vertical crash event of the Nuri pilot seat from 500 feet altitude was simulated and the maximum acceleration rate was determined using MSC PATRAN/LSDYNA. The pilot survivability was determined by comparing the result with human tolerance criteria data available in other published works. From the result, it was found that the maximum acceleration of the Nuri pilot seat was 584.4g at 19. 63 milliseconds, thus it can be concluded that the survivability aspect of the pilot is fatal when compared to other published works.

  9. Optimizing Scrip Systems: Efficiency, Crashes, Hoarders, and Altruists

    CERN Document Server

    Kash, Ian A; Halpern, Joseph Y

    2007-01-01

    We discuss the design of efficient scrip systems and develop tools for empirically analyzing them. For those interested in the empirical study of scrip systems, we demonstrate how characteristics of agents in a system can be inferred from the equilibrium distribution of money. From the perspective of a system designer, we examine the effect of the money supply on social welfare and show that social welfare is maximized by increasing the money supply up to the point that the system experiences a ``monetary crash,'' where money is sufficiently devalued that no agent is willing to perform a service. We also examine the implications of the presence of altruists and hoarders on the performance of the system. While a small number of altruists may improve social welfare, too many can also cause the system to experience a monetary crash, which may be bad for social welfare. Hoarders generally decrease social welfare but, surprisingly, they also promote system stability by helping prevent monetary crashes. In addition...

  10. Information note about the protection of nuclear facilities against aircraft crashes

    International Nuclear Information System (INIS)

    The protection of nuclear facilities against external risks (earthquakes, floods, fires etc..) is an aspect of safety taken into consideration by the French authority of nuclear safety (ASN). Concerning the aircraft crashes, the fundamental safety rules make three categories of aircraft: the small civil aircraft (weight 5.7 t). Nuclear facilities are designed to resist against crashes of aircraft from the first category only, because the probability of the accidental crash of a big aircraft are extremely low. This document comprises an information note about the protection of nuclear facilities against aircraft crashes, a dossier about the safety of nuclear facilities with respect to external risks in general (natural disasters and aircraft crashes), and an article about the protection of nuclear power plants against aircraft crashes (design, safety measures, regulation, surveillance, experience feedback). (J.S.)

  11. The role of exposure in comparisons of crash risk among different drivers and driving environments.

    Science.gov (United States)

    Chipman, M L; MacGregor, C G; Smiley, A M; Lee-Gosselin, M

    1993-04-01

    Crash rates based on drivers, driver-kilometers, and driver-days in the denominator were compared, using survey estimates of time and distance driven and the annual frequency of traffic crashes in Ontario. Rates by age, sex, and region were computed for all crashes and for crashes resulting in injury or fatality. Young male drivers remained at high risk for all types of denominator; older women had high rates when distance was included in the denominator. When time spent driving was substituted, men and women drivers over 60 had very similar rates. For comparisons of rural residents with urban and northern residents, time and distance give equivalent results. These findings suggest that apparent differences in crash risk per kilometre, whether for older women or for urban drivers, is explained by differences in typical driving speed and environment. Exposure time is better than distance to explain crash risk among drivers and regions with very different driving patterns and environments. PMID:8471119

  12. Driver crash risk factors and prevalence evaluation using naturalistic driving data.

    Science.gov (United States)

    Dingus, Thomas A; Guo, Feng; Lee, Suzie; Antin, Jonathan F; Perez, Miguel; Buchanan-King, Mindy; Hankey, Jonathan

    2016-03-01

    The accurate evaluation of crash causal factors can provide fundamental information for effective transportation policy, vehicle design, and driver education. Naturalistic driving (ND) data collected with multiple onboard video cameras and sensors provide a unique opportunity to evaluate risk factors during the seconds leading up to a crash. This paper uses a National Academy of Sciences-sponsored ND dataset comprising 905 injurious and property damage crash events, the magnitude of which allows the first direct analysis (to our knowledge) of causal factors using crashes only. The results show that crash causation has shifted dramatically in recent years, with driver-related factors (i.e., error, impairment, fatigue, and distraction) present in almost 90% of crashes. The results also definitively show that distraction is detrimental to driver safety, with handheld electronic devices having high use rates and risk. PMID:26903657

  13. Investigation of dynamics of ELM crashes and their mitigation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pankin, Alexei Y. [Tech-X Corporation, Boulder, CO (United States)

    2015-08-14

    The accurate prediction of H-mode pedestal dynamics is critical for planning experiments in existing tokamaks and in the design of future tokamaks such as ITER and DEMO. The main objective of the proposed research is to advance the understanding of the physics of H-mode pedestal. Through advances in coupled kinetic-MHD simulations, a new model for H-mode pedestal and ELM crashes as well as an improved model for the bootstrap current will be developed. ELMmitigation techniques will also be investigated. The proposed research will help design efficient confinement scenarios and reduce transient heat loads on the divertor and plasma facing components. During the last two years, the principal investigator (PI) of this proposal actively participated in physics studies related to the DOE Joint Research Targets. These studies include the modeling of divertor heat load in the DIII-D, Alcator C-Mod, and NSTX tokamaks in 2010, and the modeling of H-mode pedestal structure in the DIII-D tokamak in 2011. It is proposed that this close collaboration with experimentalists from major US tokamaks continue during the next funding period. Verification and validation will be a strong component of the proposed research. During the course of the project, advances will be made in the following areas; Dynamics of the H-mode pedestal buildup and recovery after ELM crashes – The effects of neutral fueling, particle and thermal pinches will be explored; Dynamics of ELM crashes in realistic tokamak geometries – Heat loads associated with ELM crashes will be validated against experimental measurements. An improved model for ELM crashes will be developed; ELM mitigation – The effect of resonant magnetic perturbations on ELMs stability and their evolution will be investigated; Development of a new bootstrap current model – A reduced model for will be developed through careful verification of existing models for bootstrap current against first-principle kinetic neoclassical simulations

  14. BKP plane partitions

    Energy Technology Data Exchange (ETDEWEB)

    Foda, Omar; Wheeler, Michael [Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria 3010 (Australia)

    2007-01-15

    Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another.

  15. BKP plane partitions

    OpenAIRE

    Foda, O.; Wheeler, M.

    2006-01-01

    Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another.

  16. BKP plane partitions

    International Nuclear Information System (INIS)

    Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another

  17. Homogeneous Plane Waves

    OpenAIRE

    Blau, Matthias; O'Loughlin, Martin

    2002-01-01

    Motivated by the search for potentially exactly solvable time-dependent string backgrounds, we determine all homogeneous plane wave (HPW) metrics in any dimension and find one family of HPWs with geodesically complete metrics and another with metrics containing null singularities. The former generalises both the Cahen-Wallach (constant $A_{ij}$) metrics to time-dependent HPWs, $A_{ij}(t)$, and the Ozsvath-Sch\\"ucking anti-Mach metric to arbitrary dimensions. The latter is a generalisation of ...

  18. Boundaries in digital planes

    Directory of Open Access Journals (Sweden)

    Efim Khalimsky

    1990-01-01

    Full Text Available The importance of topological connectedness properties in processing digital pictures is well known. A natural way to begin a theory for this is to give a definition of connectedness for subsets of a digital plane which allows one to prove a Jordan curve theorem. The generally accepted approach to this has been a non-topological Jordan curve theorem which requires two different definitions, 4-connectedness, and 8-connectedness, one for the curve and the other for its complement.

  19. Assessing the Residual Teen Crash Risk Factors after Graduated Drivers License Implementation

    OpenAIRE

    Thor, Craig P.; Gabler, Hampton C.

    2010-01-01

    Graduated driving licensing laws are now in place in all 50 U.S. states and the District of Columbia. However, despite stricter supervised driving requirements, restrictions on the number of passengers, and earlier nighttime driving curfews, teen drivers continue to be at a higher crash risk than the adult driving population. The National Motor Vehicle Crash Causation Survey (NMVCCS) dataset was examined to compare and contrast the primary crash factors for teen drivers (16–18 years. old) and...

  20. Real-world car-to-pedestrian-crash data from an urban centre

    OpenAIRE

    Matthes Gerrit; Stengel Dirk; Frank Matthias; Beirau Melissa; Schmucker Uli; Ekkernkamp Axel; Seifert Julia

    2010-01-01

    Abstract Background Pedestrians are at a high risk for crash and injury. This study aims at comparing data from real world crashes with data gathered from experimental settings. Methods IMPAIR (In-Depth Medical Pedestrian Accident Investigation and Reconstruction) was a prospective, observational study performed in a metropolitan area. Data was collected on-scene, from clinical records, and interviews. Data comprise crash data, details on injury pattern and injury severity. Results Thirty-sev...

  1. Non-Parametric Analyses of Log-Periodic Precursors to Financial Crashes

    OpenAIRE

    Wei-Xing Zhou; Didier Sornette

    2002-01-01

    We apply two non-parametric methods to test further the hypothesis that log-periodicity characterizes the detrended price trajectory of large financial indices prior to financial crashes or strong corrections. The analysis using the so-called (H,q)-derivative is applied to seven time series ending with the October 1987 crash, the October 1997 correction and the April 2000 crash of the Dow Jones Industrial Average (DJIA), the Standard & Poor 500 and Nasdaq indices. The Hilbert transform is app...

  2. Reproducing Context-sensitive Crashes in Mobile Apps using Crowdsourced Debugging

    OpenAIRE

    Gomez, Maria; Rouvoy, Romain; Seinturier, Lionel

    2015-01-01

    While the number of mobile apps published by app stores keeps increasing, the quality of these apps greatly varies. Unfortunately, end-users continue experiencing bugs and crashes for some of the apps installed on their mobile devices. Although developers heavily test their apps before release, context-sensitive crashes might still emerge after deployment. This paper therefore introduces MoTiF, a crowdsourced approach to support developers in automatically reproducing context-sensitive crashe...

  3. Investigating crash injury severity at unsignalized intersections in Heilongjiang Province, China

    Directory of Open Access Journals (Sweden)

    Yulong Pei

    2014-08-01

    Full Text Available Many studies suggest that more crashes occur due to mixed traffic flow at unsignalized intersections. However, very little is known about the injury severity of these crashes. The objective of this study is therefore to investigate how contributory factors affect crash injury severity at unsignalized intersections. The dataset used for this analysis derived from police crash reports from Dec. 2006 to Apr. 2009 in Heilongjiang Province, China. An ordered probit model was developed to predict the probability that the injury severity of a crash will be one of four levels : no injury, slight injury, severe injury, and fatal injury. The injury severity of a crash was evaluated in terms of the most severe injury sustained by any person involved in the crash. Results from the present study showed that different factors had varying effects on crash injury severity. Factors found to resuit in the increased probability of serious injuries include adverse weather, sideswiping with pedestrians on poor surface, the interaction of rear-ends and the third-class highway, winter night without illumination, and the interaction between traffic signs or markings and the third-class highway. Although there are some limitations in the current study, this study provides more insights into crash injury severity at unsignalized intersections.

  4. Vehicle-Barrier Tracking of a Scaled Crash Test for Roadside Barrier Design

    OpenAIRE

    Amato, Giuseppina; Ghosh, Bidisha; SIMMS, CIARAN

    2014-01-01

    In this paper the tracking system used to perform a scaled vehicle-barrier crash test is reported. The scaled crash test was performed as part of a wider project aimed at designing a new safety barrier making use of natural building materials. The scaled crash test was designed and performed as a proof of concept of the new mass-based safety barriers and the study was composed of two parts: the scaling technique and of a series of performed scaled crash tests. The scaling method was used for ...

  5. Road traffic crashes, injury and fatality trends in Sri Lanka: 1938–2013

    OpenAIRE

    2015-01-01

    Abstract Objective To analyse trends in road traffic crashes, injuries and fatalities over 75 years in Sri Lanka. Methods Data on road traffic crashes, injuries and fatalities between 1938 and 2013 were obtained from the Police Statistics Unit. Rates per 100 000 population were calculated and trends were analysed using joinpoint regression analysis. Findings Road traffic crashes and injuries rose substantially between 1938 and 2013: annual crashes increased from 61.2 to 183.6 per 100 000 peop...

  6. Relationship between crash rate and hourly traffic flow on interurban motorways

    OpenAIRE

    Martin, JL

    2002-01-01

    This paper describes the relationship between crash incidence rates and hourly traffic volume and discusses the influence of traffic on crash severity, based on observations made on 2000 km of french interurban motorways over 2 years. Incidence rates involving property damage-only crashes and injury-crashes are highest when traffic is lightest (under 400 vehicles/h). These incidence rates are at their lowest when traffic flows at a rate of 1000-1500 vehicles/h. For heavier traffic flows, cras...

  7. Determination of Selected Crash Parameters in Head-on Vehicle Collision with Rollover

    OpenAIRE

    Coufal, Tomáš; Semela, Marek

    2016-01-01

    The paper presents complete results of the head-on small overlap crash test of vehicle with driver moving at a speed of approximately 12 m/s against stationary vehicle with post-crash rollover. When a crash does not involve the main crush-zone structures, the occupant compartment is not well protected. The emphasis in the paper was put on determination and presentation of crash parameters for the application in traffic accident analyses and for simulation with the help of software for acciden...

  8. Injury severity data for front and second row passengers in frontal crashes.

    Science.gov (United States)

    Atkinson, Theresa; Leszek Gawarecki; Tavakoli, Massoud

    2016-06-01

    The data contained here were obtained from the National Highway Transportation Safety Administration׳s National Automotive Sampling System - Crashworthiness Data System (NASS-CDS) for the years 2008-2014. This publically available data set monitors motor vehicle crashes in the United States, using a stratified random sample frame, resulting in information on approximately 5000 crashes each year that can be utilized to create national estimates for crashes. The NASS-CDS data sets document vehicle, crash, and occupant factors. These data can be utilized to examine public health, law enforcement, roadway planning, and vehicle design issues. The data provided in this brief are a subset of crash events and occupants. The crashes provided are exclusively frontal crashes. Within these crashes, only restrained occupants who were seated in the right front seat position or the second row outboard seat positions were included. The front row and second row data sets were utilized to construct occupant pairs crashes where both a right front seat occupant and a second row occupant were available. Both unpaired and paired data sets are provided in this brief. PMID:27077084

  9. The effects of roadway characteristics on farm equipment crashes: A GIS approach

    Science.gov (United States)

    Greenan, Mitchell Joseph

    Tractors and other self-propelled farm equipment, such as combines, sprayers, and towed grain carts, are often used on public roadways as the primary means for traveling from homestead to homestead or from homestead to a distributer. Increased roadway exposure has led to a growing concern for crashes involving farm equipment on the public roadway. A handful of studies exist examining public roadway crashes involving farm equipment using crash data, but none thus far have evaluated road segment data to identify road-specific risk factors. The objective of this study is to identify if roadway characteristics (traffic density, speed limit, road type, surface type, road width, and shoulder width) affect the risk of a crash involving farm equipment on Iowa public roadways. A retrospective cohort study of Iowa roads was conducted to identify the types of roads that are at an increased risk of having a farm-equipment crash on them. Crash data from the Iowa Department of Transportation (to identify crashes) were spatial linked to Iowa roadway data using Geographic Information Systems (GIS). Logistic regression was used to calculate ORs and 95% CL. Out of 319,705 road segments in Iowa, 0.4% segments (n=1,337) had a farm equipment crash from 2005-2011. The odds of having a farm equipment crash were significantly higher for road segments with increased traffic density and speed limit. Roads with an average daily traffic volume of at least 1,251 vehicles were at a 5.53 times greater odds of having a crash than roads with a daily traffic volume between 0-30 vehicles. (CI: 3.90-7.83). Roads with a posted speed limit between 50mph and 60mph were at a 4.88 times greater odds of having a crash than roads with a posted speed limit of 30mph or less. (CI: 3.85-6.20). Specific roadway characteristics such as roadway and shoulder width were also associated with the risk of a crash. For every 5 foot increase in road width, the odds for a crash decreased by 6 percent (CI: 0.89-0.99) and

  10. Plane and geodetic surveying

    CERN Document Server

    Johnson, Aylmer

    2004-01-01

    Plane and Geodetic Surveying blends theory and practice, conventional techniques and GPS, to provide the ideal book for students of surveying.Detailed guidance is given on how and when the principle surveying instruments (theodolites, Total Stations, levels and GPS) should be used. Concepts and formulae needed to convert instrument readings into useful results are explained. Rigorous explanations of the theoretical aspects of surveying are given, while at the same time a wealth of useful advice about conducting a survey in practice is provided. An accompanying least squares adjustment program

  11. Explaining reduction of pedestrian–motor vehicle crashes in Arkhangelsk, Russia, in 2005–2010

    Directory of Open Access Journals (Sweden)

    Alexander V. Kudryavtsev

    2012-09-01

    Full Text Available Objective. To explain a reduction in pedestrian–motor vehicle crashes in Arkhangelsk, Russia, in 2005–2010. Study design. Retrospective ecological study. Methods. For 2005–2010, police data on pedestrian–motor vehicle crashes, traffic violations, and total motor vehicles (MVs were combined with data on changes in national road traffic legislation and municipal road infrastructure. Negative binomial regression was used to investigate trends in monthly rates of pedestrian–motor vehicle crashes per total MVs and estimate changes in these rates per unit changes in the safety measures. Results. During the 6 years, the police registered 2,565 pedestrian–motor vehicle crashes: 1,597 (62% outside crosswalks, 766 (30% on non-signalized crosswalks, and 202 (8% on signalized crosswalks. Crash rates outside crosswalks and on signalized crosswalks decreased on average by 1.1% per month, whereas the crash rate on non-signalized crosswalks remained unchanged. Numbers of signalized and non-signalized crosswalks increased by 14 and 19%, respectively. Also, 10% of non-signalized crosswalks were combined with speed humps, and 4% with light-reflecting vertical signs. Pedestrian penalties for traffic violations increased 4-fold. Driver penalties for ignoring prohibiting signal and failure to give way to pedestrian on non-signalized crosswalk increased 7- and 8-fold, respectively. The rate of total registered drivers’ traffic violations per total MVs decreased on average by 0.3% per month. All studied infrastructure and legislative measures had inverse associations with the rate of crashes outside crosswalks. The rate of crashes on signalized crosswalks showed inverse associations with related monetary penalties. Conclusions. The introduction of infrastructure and legislative measures is the most probable explanation of the reduction of pedestrian–motor vehicle crashes in Arkhangelsk. The overall reduction is due to decreases in rates of crashes

  12. Development of crash modification factors for changing lane width on roadway segments using generalized nonlinear models.

    Science.gov (United States)

    Lee, Chris; Abdel-Aty, Mohamed; Park, Juneyoung; Wang, Jung-Han

    2015-03-01

    This study evaluates the effectiveness of changing lane width in reducing crashes on roadway segments. To consider nonlinear relationships between crash rate and lane width, the study develops generalized nonlinear models (GNMs) using 3-years crash records and road geometry data collected for all roadway segments in Florida. The study also estimates various crash modification factors (CMFs) for different ranges of lane width based on the results of the GNMs. It was found that the crash rate was highest for 12-ft lane and lower for the lane width less than or greater than 12ft. GNMs can extrapolate this nonlinear continuous effect of lane width and estimate the CMFs for any lane width, not only selected lane widths, unlike generalized linear models (GLMs) with categorical variables. The CMFs estimated using GNMs reflect that crashes are less likely to occur for narrower lanes if the lane width is less than 12ft whereas crashes are less likely to occur for wider lanes if the lane width is greater than 12ft. However, these effects varied with the posted speed limits as the effect of interaction between lane width and speed limit was significant. The estimated CMFs show that crashes are less likely to occur for lane widths less than 12ft than the lane widths greater than 12ft if the speed limit is higher than or equal to 40mph. It was also found from the CMFs that crashes at higher severity levels (KABC and KAB) are less likely to occur for lane widths greater or less than 12ft compared to 12-ft lane. The study demonstrates that the CMFs estimated using GNMs clearly reflect variations in crashes with lane width, which cannot be captured by the CMFs estimated using GLMs. Thus, it is recommended that if the relationship between crash rate and lane width is nonlinear, the CMFs are estimated using GNMs. PMID:25616033

  13. Crash protectiveness to occupant injury and vehicle damage: An investigation on major car brands.

    Science.gov (United States)

    Huang, Helai; Li, Chunyang; Zeng, Qiang

    2016-01-01

    This study sets out to investigate vehicles' crash protectiveness on occupant injury and vehicle damage, which can be deemed as an extension of the traditional crash worthiness. A Bayesian bivariate hierarchical ordered logistic (BVHOL) model is developed to estimate the occupant protectiveness (OP) and vehicle protectiveness (VP) of 23 major car brands in Florida, with considering vehicles' crash aggressivity and controlling external factors. The proposed model not only takes over the strength of the existing hierarchical ordered logistic (HOL) model, i.e. specifying the order characteristics of crash outcomes and cross-crash heterogeneities, but also accounts for the correlation between the two crash responses, driver injury and vehicle damage. A total of 7335 two-vehicle-crash records with 14,670 cars involved in Florida are used for the investigation. From the estimation results, it's found that most of the luxury cars such as Cadillac, Volvo and Lexus possess excellent OP and VP while some brands such as KIA and Saturn perform very badly in both aspects. The ranks of the estimated safety performance indices are even compared to the counterparts in Huang et al. study [Huang, H., Hu, S., Abdel-Aty, M., 2014. Indexing crash worthiness and crash aggressivity by major car brands. Safety Science 62, 339-347]. The results show that the rank of occupant protectiveness index (OPI) is relatively coherent with that of crash worthiness index, but the ranks of crash aggressivity index in both studies is more different from each other. Meanwhile, a great discrepancy between the OPI rank and that of vehicle protectiveness index is found. What's more, the results of control variables and hyper-parameters estimation as well as comparison to HOL models with separate or identical threshold errors, demonstrate the validity and advancement of the proposed model and the robustness of the estimated OP and VP. PMID:26551733

  14. Homogeneous plane waves

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Matthias E-mail: mblau@ictp.trieste.it; O' Loughlin, Martin E-mail: loughlin@sissa.it

    2003-03-24

    Motivated by the search for potentially exactly solvable time-dependent string backgrounds, we determine all homogeneous plane wave (HPW) metrics in any dimension and find one family of HPWs with geodesically complete metrics and another with metrics containing null singularities. The former generalises both the Cahen-Wallach (constant A{sub ij}) metrics to time-dependent HPWs, A{sub ij}(x{sup +}), and the Ozsvath-Schuecking anti-Mach metric to arbitrary dimensions. The latter is a generalisation of the known homogeneous metrics with A{sub ij}{approx}1/(x{sup +}){sup 2} to a more complicated time-dependence. We display these metrics in various coordinate systems, show how to embed them into string theory, and determine the isometry algebra of a general HPW and the associated conserved charges. We review the Lewis-Riesenfeld theory of invariants of time-dependent harmonic oscillators and show how it can be deduced from the geometry of plane waves. We advocate the use of the invariant associated with the extra (timelike) isometry of HPWs for lightcone quantisation, and illustrate the procedure in some examples.

  15. The MOND Fundamental Plane

    CERN Document Server

    Cardone, V F; Diaferio, A; Tortora, C; Molinaro, R

    2010-01-01

    Modified Newtonian Dynamics (MOND) has been shown to be able to fit spiral galaxy rotation curves as well as giving a theoretical foundation for empirically determined scaling relations, such as the Tully - Fisher law, without the need for a dark matter halo. As a complementary analysis, one should investigate whether MOND can also reproduce the dynamics of early - type galaxies (ETGs) without dark matter. As a first step, we here show that MOND can indeed fit the observed central velocity dispersion $\\sigma_0$ of a large sample of ETGs assuming a simple MOND interpolating functions and constant anisotropy. We also show that, under some assumptions on the luminosity dependence of the Sersic n parameter and the stellar M/L ratio, MOND predicts a fundamental plane for ETGs : a log - linear relation among the effective radius $R_{eff}$, $\\sigma_0$ and the mean effective intensity $\\langle I_e \\rangle$. However, we predict a tilt between the observed and the MOND fundamental planes.

  16. Homogeneous plane waves

    International Nuclear Information System (INIS)

    Motivated by the search for potentially exactly solvable time-dependent string backgrounds, we determine all homogeneous plane wave (HPW) metrics in any dimension and find one family of HPWs with geodesically complete metrics and another with metrics containing null singularities. The former generalises both the Cahen-Wallach (constant Aij) metrics to time-dependent HPWs, Aij(x+), and the Ozsvath-Schuecking anti-Mach metric to arbitrary dimensions. The latter is a generalisation of the known homogeneous metrics with Aij∼1/(x+)2 to a more complicated time-dependence. We display these metrics in various coordinate systems, show how to embed them into string theory, and determine the isometry algebra of a general HPW and the associated conserved charges. We review the Lewis-Riesenfeld theory of invariants of time-dependent harmonic oscillators and show how it can be deduced from the geometry of plane waves. We advocate the use of the invariant associated with the extra (timelike) isometry of HPWs for lightcone quantisation, and illustrate the procedure in some examples

  17. Homogeneous Plane Waves

    CERN Document Server

    Blau, Matthias; Blau, Matthias; Loughlin, Martin O'

    2003-01-01

    Motivated by the search for potentially exactly solvable time-dependent string backgrounds, we determine all homogeneous plane wave (HPW) metrics in any dimension and find one family of HPWs with geodesically complete metrics and another with metrics with null singularities. The former generalises both the Cahen-Wallach (constant $A_{ij}$) metrics to time-dependent HPWs, $A_{ij}(t)$, and the Ozsvath-Sch\\"ucking anti-Mach metric to arbitrary dimensions. The latter is a generalisation of the known homogeneous metrics with $A_{ij}\\sim 1/t^2$ to a more complicated time-dependence. We display these metrics in various coordinate systems, show how to embed them into string theory, and determine the isometry algebra of a general HPW and the associated conserved charges. We review the Lewis-Riesenfeld theory of invariants of time-dependent harmonic oscillators and show how it can be deduced from the geometry of plane waves. We advocate the use of the invariant associated with the extra (timelike) isometry of HPWs for ...

  18. Analysis of 86 fatal motorcycle frontal crashes in Chongqing, China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hui; HUANG Wei; YANG Guang-yu; CHEN Rong; LIU Sheng-xiong; YU Yong-min; YIN Zhi-yong; WANG Zheng-guo

    2012-01-01

    Objective: To analyze the injuries of motorcyclists involved in fatal motorcycle frontal crashes.Methods: A survey group involving multi-discipline experts was built to randomly collect data on fatal motorcycle frontal collision accidents that occurred in Chongqing during 2006-2010.The sampled information included medical or autopsy reports,blood alcohol concentration (BAC)level,helmet use,accident witness,field sketch as well as field photos.The motorcyclist injuries were scored according to the Abbreviated Injury Scale (AIS) 2005.The involved riders with a BAC level≥20 mg/ml were attributed to alcohol use.Data were processed statistically with nonparametric test via software SPSS 11.0.Results:A total of 86 fatal motorcycle frontal crashes were sampled and further analyzed.The age of motorcyclists enrolled in this investigation showed nominal distribution and the middle-aged (30-39 years) occupied the highest percentage of fatalities.There were only 14 motorcyclists (16.3%) wearing helmets at the moment ofcollision.And 12.8% of these motorcyclist crashes were attributable to alcohol use.Impact injury was the main fatal cause,accounting for 72% of motorcyclist deaths,followed by tumbling injury (26%) and run-over (2%).Respectively 84%,22% and 19%of motorcyclists who sustained head,chest and abdominal trauma died.Extremity injury was the most frequently observed injury type.Conclusions: This investigation is helpful to build accident prevention programs and develop protection devices which may effectively mitigate injuries and prevent deaths following motorcycle frontal collision accidents.Further investigations on motorcycle collision accidents are still needed.

  19. Commuter motorcycle crashes in Malaysia: An understanding of contributing factors.

    Science.gov (United States)

    Oxley, Jennifer; Yuen, Jeremy; Ravi, Mano Deepa; Hoareau, Effie; Mohammed, Mohammed Azman Aziz; Bakar, Harun; Venkataraman, Saraswathy; Nair, Prame Kumar

    2013-01-01

    In Malaysia, two-thirds of reported workplace-related fatal and serious injury incidents are the result of commuting crashes (especially those involving motorcyclists), however, little is known about the contributing factors to these collisions. A telephone survey of 1,750 motorcyclists (1,004 adults who had been involved in a motorcycle commuting crash in the last 2 years and 746 adult motorcyclists who had not been involved in a motorcycle crash in the last 2 years) was undertaken. The contributions of a range of behavioural, attitudinal, employment and travel pattern factors to collision involvement were examined. The findings revealed that the majority of participants were licensed riders, rode substantial distances (most often for work purposes), and reported adopting safe riding practices (helmet wearing and buckling). However, there were some concerning findings regarding speeding behaviour, use of mobile phones while riding, and engaging in other risky behaviours. Participants who had been involved in a collision were younger (aged 25-29 years), had higher exposure (measured by distances travelled, frequency of riding, and riding on high volume and higher speed roads), reported higher rates of riding for work purposes, worked more shift hours and had a higher likelihood of riding at relatively high speeds compared with participants who had not been involved in a collision. Collisions generally occurred during morning and early evening hours, striking another vehicles, and during normal traffic flow. The implications of these findings for policy decisions and development of evidence-based behavioural/training interventions addressing key contributing factors are discussed. PMID:24406945

  20. The role of alcohol in Thailand motorcycle crashes.

    Science.gov (United States)

    Kasantikul, Vira; Ouellet, James V; Smith, Terry; Sirathranont, Jetn; Panichabhongse, Viratt

    2005-03-01

    In order to identify motorcycle accident cause factors and countermeasures in Thailand, a large prospective study was undertaken. Researchers conducted on-scene, in-depth investigation and reconstruction of 969 collisions involving 1082 motorcycle riders. Accidents were randomly sampled and included all levels of injury severity. Alcohol proved to be the most outstanding cause factor, with 393 drinking riders in crashes. Alcohol accidents were distinctly different from non-alcohol crashes. Alcohol accidents were more frequent on weekends and particularly at night, usually when the rider was on his way home. Drinking riders were more likely to lose control of the motorcycle, usually by running off the road. They were more likely to be in a single vehicle accident, to violate traffic control signals, and to be in non-intersection collisions. Males were far more likely to drink and ride than females. Drinking riders were far more likely to be inattentive to the driving task just before they crashed, and to be the primary or sole cause of the accident. One-fourth of all riders did not go to the hospital, and another 42% needed only treatment in the emergency room. Drinking riders were more likely to be hospitalized and far more likely to be killed. The higher hospitalization and fatality rates of drinking riders resulted from the kinds of accidents in which they were involved, not from the minimal differences in speeds and helmet use. Problems with balance and coordination were about equally rare among drinking and non-drinking riders. Inattention was a far greater contributing factor. PMID:15667823

  1. Road crash in China from 2003 to 2005

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ji-hong; QIU Jun; ZHAO Xin-cai; LIU Guo-dong; XIAO Kai; ZHANG Liang; JIANG Zhi-quan; WANG Zheng-guo

    2008-01-01

    Objective: To analyze characteristics and causes of road crash and injuries in China from 2003 to 2005.Methods : The data of road crash in 2003-2005 were collected to study the characteristics including total vehicle number, occurrence rates of traffic accidents and serious traffic accidents so as to discuss the causes and characteristics of road crash in China.Results: From 2003 to 2005, the numbers of traffic accidents, injuries and deaths as well as the mortality rates per 100 000 persons and per 10 000 vehicles declined in China. Until 2005, the total number of traffic accidents decreased to 450 000 and deaths to 99 000, with the mortality rate per 10 000 vehicles being 7.6 persons. While the drivers and passengers accounted for 33.2% and 26.6% of death casualties respectively in 2005. Most traffic accidents were caused by drivers, especially those with driving experience less than 3 years. Traffic accidents occurred on suburban roads accounted for 60%. The mortality rate of the traffic accidents per 100 km on the first grade road ranked the highest. The mortality rate of the traffic accidents on expressways ranked the highest, with continual increase of death and injury.Conclusions: At present, the increase trend of traffic accidents and casualties in China has been slowed down to some extent and shows a declining tendency, but the situation is far away from being optimistic. In order to cut down the number of traffic accidents and casualties, we should pay more attention to training and managing drivers with less than three driving years and those driving buses. Strict prevention measures should be laid on traffic accidents on first grade roads, expressways and suburban roads as well as the enhancement on improving first-aid system.

  2. Lower extremity finite element model for crash simulation

    Energy Technology Data Exchange (ETDEWEB)

    Schauer, D.A.; Perfect, S.A.

    1996-03-01

    A lower extremity model has been developed to study occupant injury mechanisms of the major bones and ligamentous soft tissues resulting from vehicle collisions. The model is based on anatomically correct digitized bone surfaces of the pelvis, femur, patella and the tibia. Many muscles, tendons and ligaments were incrementally added to the basic bone model. We have simulated two types of occupant loading that occur in a crash environment using a non-linear large deformation finite element code. The modeling approach assumed that the leg was passive during its response to the excitation, that is, no active muscular contraction and therefore no active change in limb stiffness. The approach recognized that the most important contributions of the muscles to the lower extremity response are their ability to define and modify the impedance of the limb. When nonlinear material behavior in a component of the leg model was deemed important to response, a nonlinear constitutive model was incorporated. The accuracy of these assumptions can be verified only through a review of analysis results and careful comparison with test data. As currently defined, the model meets the objective for which it was created. Much work remains to be done, both from modeling and analysis perspectives, before the model can be considered complete. The model implements a modeling philosophy that can accurately capture both kinematic and kinetic response of the lower limb. We have demonstrated that the lower extremity model is a valuable tool for understanding the injury processes and mechanisms. We are now in a position to extend the computer simulation to investigate the clinical fracture patterns observed in actual crashes. Additional experience with this model will enable us to make a statement on what measures are needed to significantly reduce lower extremity injuries in vehicle crashes. 6 refs.

  3. Epidemiology, Causes and Prevention of Car Rollover Crashes with Ejection

    OpenAIRE

    El-Hennawy, HM; El-Menyar, A; Al-Thani, H; Tuma, M; Parchani, A; H. Abdulrahman; Peralta, R; Asim, M.; Zarour, A; Latifi, R

    2014-01-01

    Rollover crashes (ROCs) are responsible for almost a third of all highway vehicle occupant fatalities. Although ROCs are common and serious mechanism of injury, ROCs are under-reported. To analyze the causes, mechanism, impact and prevention of ROCs, we reviewed the literature between 1984 and 2013. By utilizing the search engines PubMed, MEDLINE and EMBASE by using key words “ROCs” “Ejection” and “vehicle” the initial search yielded 241 abstracts, of which 58 articles were relevant. Most of ...

  4. Risk exposure and crash involvement rates of occasional drivers

    OpenAIRE

    Fontaine, H

    2001-01-01

    This paper describes how nearly half the cars in France are driven by more than one person. Generally, there is one principal driver who covers the greatest distance in the car and one or more occasional drivers. Many studies of risk that link crash data with car travel data only consider the risk exposure of principal drivers because of a lack of more detailed information on the different drivers of a particular car. It is however important to determine what percentage of total distance bein...

  5. A different perspective on conspicuity related motorcycle crashes.

    OpenAIRE

    Craen, S. de Doumen, M.J.A. & Norden, Y. van

    2013-01-01

    The most common type of conflict in which a motorcyclist is injured or killed is a collision between a motorcycle and a car, often in priority situations. Many studies on motorcycle safety focus on the question why car drivers fail to give priority and on the poor conspicuity of motorcycles. The concept of ‘looked-but-failed-to-see’ crashes is a recurring item. On the other hand, it is not entirely unexpected that motorcycles have many conflicts with cars; there simply are so many cars on the...

  6. Rebreathing in a subject wearing an integral crash helmet.

    OpenAIRE

    Greenbaum, R; Malins, A F; Davies, R.; Baskett, P J

    1982-01-01

    The respired air of a volunteer was analysed while he was wearing a variety of integral crash helmets. Observations were made with and without a protective balaclava, bib or scarf, or both. Rebreathing occurred and the peak inspired oxygen tension fell as low as 16.0 kPa (120 mm Hg) with a minimum inspired carbon dioxide of 2.1 KPa (16.0 mm Hg). Accessories worn or attached to the helmet which restrict airflow into the helmet should not be used. Attention should be paid to the "air conditioni...

  7. Airbag Effectiveness on Brain Trauma in Frontal Crashes

    OpenAIRE

    Pintar, Frank A.; Yoganandan, Narayan; Gennarelli, Thomas A.

    2000-01-01

    The purpose of this study was to evaluate the effectiveness of frontal restraint systems in reducing the potential for head injuries, specifically brain injuries and skull fractures. The US DOT NASS database files from 1991–1998 were evaluated for drivers and right front seat occupants in frontal crashes. Of the total driver and right front seat occupants in this data set, 3.83% sustained a brain injury without skull fracture, 0.05% sustained a skull fracture without a brain injury, and 0.16%...

  8. 75 FR 50958 - Federal Motor Vehicle Safety Standards; Motorcoach Definition; Occupant Crash Protection

    Science.gov (United States)

    2010-08-18

    ... Standards; Motorcoach Definition; Occupant Crash Protection AGENCY: National Highway Traffic Safety.... Stage 2: Frontal Sled Tests VI. Proposed Requirements a. Adding a Definition of ``Motorcoach'' to 49 CFR... frontal 48 kilometers per hour (km/h) (30 miles per hour (mph)) barrier crash test with instrumented...

  9. Crash Frequency Modeling Using Real-Time Environmental and Traffic Data and Unbalanced Panel Data Models.

    Science.gov (United States)

    Chen, Feng; Chen, Suren; Ma, Xiaoxiang

    2016-01-01

    Traffic and environmental conditions (e.g., weather conditions), which frequently change with time, have a significant impact on crash occurrence. Traditional crash frequency models with large temporal scales and aggregated variables are not sufficient to capture the time-varying nature of driving environmental factors, causing significant loss of critical information on crash frequency modeling. This paper aims at developing crash frequency models with refined temporal scales for complex driving environments, with such an effort providing more detailed and accurate crash risk information which can allow for more effective and proactive traffic management and law enforcement intervention. Zero-inflated, negative binomial (ZINB) models with site-specific random effects are developed with unbalanced panel data to analyze hourly crash frequency on highway segments. The real-time driving environment information, including traffic, weather and road surface condition data, sourced primarily from the Road Weather Information System, is incorporated into the models along with site-specific road characteristics. The estimation results of unbalanced panel data ZINB models suggest there are a number of factors influencing crash frequency, including time-varying factors (e.g., visibility and hourly traffic volume) and site-varying factors (e.g., speed limit). The study confirms the unique significance of the real-time weather, road surface condition and traffic data to crash frequency modeling. PMID:27322306

  10. The Thule episode epidemiological follow up after the crash of a B-52 bomber in Greenland

    DEFF Research Database (Denmark)

    Juel, K

    1992-01-01

    The aim was to explore the pattern of disease in staff associated with a bomber that crashed in 1968 when carrying nuclear bombs.......The aim was to explore the pattern of disease in staff associated with a bomber that crashed in 1968 when carrying nuclear bombs....

  11. Study Shows Just How Big a Role Cellphones Play in Car Crashes

    Science.gov (United States)

    ... Just How Big a Role Cellphones Play in Car Crashes In-vehicle videos highlight other distractions, such as ... the wheel, researchers report that video taken inside cars showed drivers were ... of crashes. Not surprisingly, the findings link cellphone use to ...

  12. The roles of motorcyclists and car drivers in conspicuity-related motorcycle crashes.

    NARCIS (Netherlands)

    Craen, S. de Doumen, M. Bos, N. & Norden, Y. van

    2012-01-01

    This report gives an overview of the available research on the different factors of influence on the perception of motorcycles. It also presents analyses of Dutch motorcycle crashes which provide a description of the relative occurrence of car-motorcycle crashes in the Netherlands. Finally, this rep

  13. Piercing of the containment shell of a reactor building in case of airplane crash

    International Nuclear Information System (INIS)

    The author presents a simple calculation model for a realistic check of the piercing safety of containments of reactor buildings in case of airplane crash. Its application is illustrated by a numerical example (Starfighter crash on the Unterweser nuclear power plant). (orig.)

  14. 77 FR 32712 - Technical Report: Evaluation of the Enhancing Vehicle-to-Vehicle Crash Compatibility Agreement...

    Science.gov (United States)

    2012-06-01

    ...This notice announces NHTSA's publication of a Technical Report reviewing and evaluating the Enhancing Vehicle-to-Vehicle Crash Compatibility Agreement. The report's title is: Evaluation of the Enhancing Vehicle-to-Vehicle Crash Compatibility Agreement: Effectiveness of the Primary and Secondary Energy-Absorbing Structures on Pickup Trucks and...

  15. Bicycle Guidelines and Crash Rates on Cycle Tracks in the United States

    Science.gov (United States)

    Morency, Patrick; Miranda-Moreno, Luis F.; Willett, Walter C.; Dennerlein, Jack T.

    2013-01-01

    Objectives. We studied state-adopted bicycle guidelines to determine whether cycle tracks (physically separated, bicycle-exclusive paths adjacent to sidewalks) were recommended, whether they were built, and their crash rate. Methods. We analyzed and compared US bicycle facility guidelines published between 1972 and 1999. We identified 19 cycle tracks in the United States and collected extensive data on cycle track design, usage, and crash history from local communities. We used bicycle counts and crash data to estimate crash rates. Results. A bicycle facility guideline written in 1972 endorsed cycle tracks but American Association of State Highway and Transportation Officials (AASHTO) guidelines (1974–1999) discouraged or did not include cycle tracks and did not cite research about crash rates on cycle tracks. For the 19 US cycle tracks we examined, the overall crash rate was 2.3 (95% confidence interval = 1.7, 3.0) per 1 million bicycle kilometers. Conclusions. AASHTO bicycle guidelines are not explicitly based on rigorous or up-to-date research. Our results show that the risk of bicycle–vehicle crashes is lower on US cycle tracks than published crashes rates on roadways. This study and previous investigations support building cycle tracks. PMID:23678920

  16. 76 FR 46359 - Announcing the Nineteenth Public Meeting of the Crash Injury Research and Engineering Network...

    Science.gov (United States)

    2011-08-02

    ...This notice announces the Nineteenth Public Meeting of members of the Crash Injury Research and Engineering Network. CIREN is a collaborative effort to conduct research on crashes and injuries at six Level I Trauma Centers across the United States linked by a computer network. The current CIREN model utilizes two types of centers, medical and engineering. Medical centers are based at Level I......

  17. 76 FR 53648 - Federal Motor Vehicle Safety Standards: Occupant Crash Protection

    Science.gov (United States)

    2011-08-29

    ... Standards: Occupant Crash Protection AGENCY: National Highway Traffic Safety Administration (NHTSA... vehicle safety standard (FMVSS) on occupant crash protection to remove the sunset of a requirement that a... vehicle seats. The NPRM preceding this final rule was published September 12, 2008 (73 FR 52939, Docket...

  18. Simulations of Pedestrian Impact Collisions with Virtual CRASH 3 and Comparisons with IPTM Staged Tests

    CERN Document Server

    Becker, Tony; Scurlock, Bob

    2015-01-01

    In this article, we present results from a series of Virtual CRASH-based pedestrian impact simulations. We compare the results of these Virtual CRASH pedestrian impact simulations to data from pedestrian impact collisions staged at the Institute of Police Technology and Management.

  19. Duality and noncommutative planes

    DEFF Research Database (Denmark)

    Jøndrup, Søren

    2015-01-01

    We study extensions of simple modules over an associative ring A   and we prove that for twosided ideals mm and nn with artinian factors the condition ExtA1(A/m,A/n)≠0 holds for the left A  -modules A/mA/m and A/nA/n if and only if it holds for the right modules A/nA/n and A/mA/m. The methods pro...... proving this are applied to show that noncommutative models of the plane, i.e. algebras of the form k〈x,y〉/(f)k〈x,y〉/(f), where f∈([x,y])f∈([x,y]) are noetherian only in case (f)=([x,y])...

  20. Assessment of aircraft crash FR-equency for the Hanford site 200 Area tank farms

    International Nuclear Information System (INIS)

    Two factors, the near-airport crash FR-equency and the non-airport crash FR-equency, enter into the estimate of the annual aircraft crash FR-equency at a facility. The near-airport activities, Le., takeoffs and landings FR-om any of the airports in a 23-statute-mile (smi) (20-nautical-mile, [nmi]) radius of the facilities, do not significantly contribute to the annual aircraft crash FR-equency for the 200 Area tank farms. However, using the methods of DOE-STD-3014-96, the total FR-equency of an aircraft crash for the 200 Area tank farms, all FR-om non-airport operations, is calculated to be 7.10E-6/yr. Thus, DOE-STD-3014-96 requires a consequence analysis for aircraft crash. This total FR-equency consists of contributions FR-om general aviation, helicopter activities, commercial air carriers and air taxis, and FR-om large and small military aircraft. The major contribution to this total is FR-om general aviation with a FR-equency of 6.77E-6/yr. All other types of aircraft have less than 1E-6/yr crash FR-equencies. The two individual aboveground facilities were in the realm of 1E-7/yr crash FR-equencies: 204-AR Waste Unloading Facility at 1.56E-7, and 242-T Evaporator at 8.62E-8. DOE-STD-3009-94, ''Preparation Guide for U.S. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', states that external events, such as aircraft crashes, are referred to as design basis accidents (DBA) and analyzed as such: ''if FR-equency of occurrence is estimated to exceed 10-6/yr conservatively calculated'' DOE-STD-3014-96 considers its method for estimating aircraft crash FR-equency as being conservative. Therefore, DOE-STD-3009-94 requires DBA analysis of an aircraft crash into the 200 Area tank farms. DOE-STD-3009-94 also states that beyond-DBAs are not evaluated for external events. Thus, it requires only a DBA analysis of the effects of an aircraft crash into the 200 Area tank farms. There are two attributes of an aircraft crash into a Hanford waste

  1. Estimating costs of traffic crashes and crime: tools for informed decision making.

    Science.gov (United States)

    Streff, F M; Molnar, L J; Cohen, M A; Miller, T R; Rossman, S B

    1992-01-01

    Traffic crashes and crime both impose significant economic and social burdens through injury and loss of life, as well as property damage and loss. Efforts to reduce crashes and crime often result in competing demands on limited public resources. Comparable and up-to-date cost data on crashes and crime contribute to informed decisions about allocation of these resources in important ways. As a first step, cost data provide information about the magnitude of the problems of crashes and crime by allowing us to estimate associated dollar losses to society. More importantly, cost data on crashes and crime are essential to evaluating costs and benefits of various policy alternatives that compete for resources. This paper presents the first comparable comprehensive cost estimates for crashes and crime and applies them to crash and crime incidence data for Michigan to generate dollar losses for the state. An example illustrates how cost estimates can be used to evaluate costs and benefits of crash-reduction and crime-reduction policies in making resource allocation decisions. Traffic crash and selected index crime incidence data from the calendar year 1988 were obtained from the Michigan State Police. Costs for crashes and index crimes were generated and applied to incidence data to estimate dollar losses from crashes and index crimes for the state of Michigan. In 1988, index crimes in Michigan resulted in $0.8 billion in monetary costs and $2.4 billion in total monetary and nonmonetary quality-of-life costs (using the willingness-to-pay approach). Traffic crashes in Michigan resulted in $2.3 billion in monetary costs and $7.1 billion in total monetary and nonmonetary quality-of-life costs, nearly three times the costs of index crimes. Based on dollar losses to the state, the magnitude of the problem of traffic crashes clearly exceeded that of index crimes in Michigan in 1988. From a policy perspective, summing the total dollar losses from crashes or crime is of less

  2. The Association between Regional Environmental Factors and Road Trauma Rates: A Geospatial Analysis of 10 Years of Road Traffic Crashes in British Columbia, Canada

    Science.gov (United States)

    Brubacher, Jeffrey R.; Chan, Herbert; Erdelyi, Shannon; Schuurman, Nadine; Amram, Ofer

    2016-01-01

    Background British Columbia, Canada is a geographically large jurisdiction with varied environmental and socio-cultural contexts. This cross-sectional study examined variation in motor vehicle crash rates across 100 police patrols to investigate the association of crashes with key explanatory factors. Methods Eleven crash outcomes (total crashes, injury crashes, fatal crashes, speed related fatal crashes, total fatalities, single-vehicle night-time crashes, rear-end collisions, and collisions involving heavy vehicles, pedestrians, cyclists, or motorcyclists) were identified from police collision reports and insurance claims and mapped to police patrols. Six potential explanatory factors (intensity of traffic law enforcement, speed limits, climate, remoteness, socio-economic factors, and alcohol consumption) were also mapped to police patrols. We then studied the association between crashes and explanatory factors using negative binomial models with crash count per patrol as the response variable and explanatory factors as covariates. Results Between 2003 and 2012 there were 1,434,239 insurance claim collisions, 386,326 police reported crashes, and 3,404 fatal crashes. Across police patrols, there was marked variation in per capita crash rate and in potential explanatory factors. Several factors were associated with crash rates. Percent roads with speed limits ≤ 60 km/hr was positively associated with total crashes, injury crashes, rear end collisions, and collisions involving pedestrians, cyclists, and heavy vehicles; and negatively associated with single vehicle night-time crashes, fatal crashes, fatal speeding crashes, and total fatalities. Higher winter temperature was associated with lower rates of overall collisions, single vehicle night-time collisions, collisions involving heavy vehicles, and total fatalities. Lower socio-economic status was associated with higher rates of injury collisions, pedestrian collisions, fatal speeding collisions, and fatal

  3. Cyclist–motorist crash patterns in Denmark: A latent class clustering approach

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2013-01-01

    Objective: The current study aimed at uncovering patterns of cyclist–motorist crashes in Denmark and investigating their prevalence and severity. The importance of implementing clustering techniques for providing a holistic overview of vulnerable road users’ crash patterns derives from the need to...... prioritize safety issues and to devise efficient preventive measures. Method: The current study focused on cyclist–motorist crashes that occurred in Denmark during the period between 2007 and 2011. To uncover crash patterns, the current analysis applied latent class clustering, an unsupervised probabilistic...... clustering approach that relies on the statistical concept of likelihood and allows partial overlap across clusters. Results: The analysis yielded 13 distinguishable cyclist–motorist latent classes. Specific crash patterns for urban and rural areas were revealed. Prevalent features that allowed...

  4. Risk factors associated with crash severity on low-volume rural roads in Denmark

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Rasmussen, Thomas Kjær; Kaplan, Sigal

    crashes were identified by map-matching the crash location to the geographic information system representing the national transport network and extracting the relevant crashes based on annual average traffic volumes. Injury severity was modeled by estimating a generalized ordered logit model due to its...... advantage in accommodating the ordered-response nature of severity while relaxing the proportional odds assumption. Model estimates and pseudo-elasticities show that aggravated crash injury severity is significantly associated with (i) alcohol and failure to wear seatbelts, (ii) involvement of vulnerable......Safety on low-volume rural roads is drawing attention due to the high fatality and severe injury rates in comparison with high-volume roads and the increasing awareness of sustainable rural development among policy makers. This study analyzes the risk factors associated with crash severity on low...

  5. Risk Factors Associated with Crash Severity on Low-Volume Rural Roads in Denmark

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Rasmussen, Thomas Kjær; Kaplan, Sigal

    2014-01-01

    crashes were identified by map-matching the crash location to the geographic information system representing the national transport network and extracting the relevant crashes based on annual average traffic volumes. Injury severity was modeled by estimating a generalized ordered logit model due to its...... advantage in accommodating the ordered-response nature of severity while relaxing the proportional odds assumption. Model estimates and pseudoelasticities show that aggravated crash injury severity is significantly associated with (1) alcohol and failure to wear seatbelts, (2) involvement of vulnerable road......Safety on low-volume rural roads is drawing attention due to the high fatality and severe injury rates in comparison with high-volume roads and the increasing awareness of sustainable rural development among policy makers. This study analyzes the risk factors associated with crash severity on low...

  6. Evaluation of vehicle damage involved in road crashes based on quantificated model

    Institute of Scientific and Technical Information of China (English)

    FAN Yan-hui; XU Hong-guo; JIANG Hua-ping

    2008-01-01

    Based on economics theory, social value loss caused by vehicle involved in crashes as well as various factors influencing on it were analyzed, the corresponding micro-econometrics model was theoretically given. Moreover, the practicability of the model,the veracity and rationality of quantification were analyzed. Based on probability theory and mathematical statistical theory, macro approach to evaluating vehicle damage in crashes was presented, and the corresponding macro-econometrics model was constructed. In addition, the macro-econometrics model was utilized to assess economic loss from statistical data of vehicle damaged in crashes, which has shown that the model can meet the demand of quantification analysis of vehicle damage, and be applied to the evaluation of economic loss caused by crashes. The results in this paper will be of practical significance for scientific, comprehensive and rational evaluating socio-economic loss caused by road crashes.

  7. Damage assessment of nuclear containment against aircraft crash

    International Nuclear Information System (INIS)

    Highlights: • Damage assessment of nuclear containment is studied against aircraft crash. • Four impact locations have been identified at the outer containment shell. • The mid of the total height has been found to be most vulnerable location. • The crown of dome has been found to be the strongest location. • Phantom F4 caused more localized and severe damage compared to other aircrafts. - Abstract: The behavior of nuclear containment structure has been studied against aircraft crash with an emphasis on the influence of strike location. The impact locations identified on the BWR Mark III type nuclear containment structure are mid-height, junction of dome and cylinder, crown of dome and arc of dome. The containment at each of the above locations has been impacted normally by Phantom F-4, Boeing 707-320 and Airbus A320 aircrafts. The loading of the aircraft has been assigned through the corresponding reaction-time response curve. ABAQUS/Explicit finite element code has been used to carry out the three-dimensional numerical simulations. The concrete damaged plasticity model was used to simulate the behavior of concrete while the behavior of steel reinforcement was incorporated using the Johnson–Cook elasto-viscoplastic material model. The mid-height of containment has been found to experience most severe deformation against each aircraft. Phantom F4 has been found to be most disastrous at each location. The results have been compared with those of the available studies with respect to the containment deformation

  8. Numerical simulation of aircraft crash on nuclear containment structure

    International Nuclear Information System (INIS)

    Highlights: ► The deformation was more localised at the center of cylindrical portion. ► The peak deflection at the junction of dome and cylinder was found to be 67 mm. ► The peak deflection at midpoint of the cylindrical portion was found to be 88.9 mm. ► The strain rate was found to be an important parameter to effect the deformation. ► The model without strain rate and 290 s−1 strain rate predicted very high deformations. - Abstract: Numerical simulations were carried with ABAQUS/Explicit finite element code in order to predict the response of BWR Mark III type nuclear containment against Boeing 707-320 aircraft crash. The load of the aircraft was applied using and force history curve. The damaged plasticity model was used to predict the behavior of concrete while the Johnson–Cook elasto-viscoplastic material model was used to incorporate the behavior of steel reinforcement. The crash was considered to occur at two different locations i.e., the midpoint of the cylindrical portion and the junction of dome and cylinder. The midpoint of the cylindrical portion experienced more deformation. The strain rate in the material model was varied and found to have a significant effect on the response of containment. The results of the present investigation were compared with those of the studies available in literature and a close agreement with the previous results was found in terms of maximum target deformation.

  9. Crash simulation of UNS electric vehicle under frontal front impact

    Science.gov (United States)

    Susilo, D. D.; Lukamana, N. I.; Budiana, E. P.; Tjahjana, D. D. D. P.

    2016-03-01

    Sebelas Maret University has been developing an Electric Vehicle namely SmarT-EV UNS. The main structure of the car are chasis and body. The chasis is made from steel and the body is made from fiberglass composite. To ensure the safety of the car, both static and dynamic tests were carried out to these structures, including their materials, like: tensile test, bending test, and impact test. Another test needed by this vehicle is crashworthiness test. To perform the test, it is needed complex equipments and it is quite expensive. Another way to obtain vehicle crashworthiness behaviour is by simulate it. The purpose of this study was to simulate the response of the Smart-EV UNS electric vehicle main structure when crashing rigid barrier from the front. The crash simulation was done in according to the NHTSA (National Highway Traffic Safety Administration) within the speed of the vehicle of 35 mph. The UNS Electric Vehicle was modelled using SolidWorks software, and the simulation process was done by finite element method using ANSYS software. The simulation result showed that the most internal impact energy was absorbed by chassis part. It absorbed 76.2% of impact energy, then the base absorbed 11.3 %, while the front body absorbed 2.5 %, and the rest was absorbed by fender, hood, and other parts.

  10. Spinal cord injuries from road traffic crashes in southeastern Iran

    Institute of Scientific and Technical Information of China (English)

    Mohammad R Rasouli; Mohsen Nouri; Vafa Rahimi-Movaghar

    2007-01-01

    Objective: To analyze the data of patients with spinal cord injury (SCI) induced by road traffic crashes in southeastern Iran for better understanding the pattern of these injuries and therefore for better designing health system planning.Methods: In this historical cohort study, the patients who had been transferred to Level I trauma center in southeastern Iran due to road traffic accidents with radiographic documented SCI were evaluated.Results: Among 64 patients with SCI, 38 patients (59.4%, 36 males and 2 females, aged 27.42 years ± 9.44 years on average) were injured by road traffic accidents.Car and motorcycle accidents were responsible for 26 cases (68.4%) and 12 cases (31.6%), respectively. And 31 patients (81. 6%) had complete SCI. Conus medularis (T12-L2) was the most affected level.Conclusions: Results are discussed in terms of preventive measures, specifically those concerning the use of restraint and helmet and driving behavior. This study should be extended nationally to gain a larger case series so that the SCI risk of particular vehicle configurations,considering other crash factors, can be more precisely quantified and the characteristics for low occurrence of SCI can be more precisely identified.

  11. Damage assessment of nuclear containment against aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Mohd Ashraf, E-mail: iqbal_ashraf@rediffmail.com; Sadique, Md. Rehan, E-mail: rehan.sadique@gmail.com; Bhargava, Pradeep, E-mail: bhpdpfce@iitr.ac.in; Bhandari, N.M., E-mail: nmbcefce@iitr.ac.in

    2014-10-15

    Highlights: • Damage assessment of nuclear containment is studied against aircraft crash. • Four impact locations have been identified at the outer containment shell. • The mid of the total height has been found to be most vulnerable location. • The crown of dome has been found to be the strongest location. • Phantom F4 caused more localized and severe damage compared to other aircrafts. - Abstract: The behavior of nuclear containment structure has been studied against aircraft crash with an emphasis on the influence of strike location. The impact locations identified on the BWR Mark III type nuclear containment structure are mid-height, junction of dome and cylinder, crown of dome and arc of dome. The containment at each of the above locations has been impacted normally by Phantom F-4, Boeing 707-320 and Airbus A320 aircrafts. The loading of the aircraft has been assigned through the corresponding reaction-time response curve. ABAQUS/Explicit finite element code has been used to carry out the three-dimensional numerical simulations. The concrete damaged plasticity model was used to simulate the behavior of concrete while the behavior of steel reinforcement was incorporated using the Johnson–Cook elasto-viscoplastic material model. The mid-height of containment has been found to experience most severe deformation against each aircraft. Phantom F4 has been found to be most disastrous at each location. The results have been compared with those of the available studies with respect to the containment deformation.

  12. Self-harm and risk of motor vehicle crashes among young drivers : findings from the DRIVE Study

    NARCIS (Netherlands)

    Martiniuk, Alexandra L. C.; Ivers, Rebecca Q.; Glozier, Nick; Patton, George C.; Lam, Lawrence T.; Boufous, Soufiane; Senserrick, Teresa; Williamson, Ann; Stevenson, Mark; Norton, Robyn

    2009-01-01

    Background: Some motor vehicle crashes, particularly single-vehicle crashes, may result from intentional self-harm. We conducted a prospective cohort study to assess the risk that intentional self-harm poses for motor vehicle crashes among young drivers. Methods: We prospectively linked survey data

  13. Modeling the effect of operator and passenger characteristics on the fatality risk of motorcycle crashes

    Directory of Open Access Journals (Sweden)

    Ali Tavakoli Kashani

    2016-01-01

    Full Text Available BACKGROUND:In Iran more than 25% of crash fatalities belong to motorcycle operators and passengers in the recent years, from which about 20% are related to passenger fatalities. METHODS: The aim of this study was to investigate the motorcycle operator and passenger characteristics as well as other contributory factors that may affect the fatality risk of motorcyclists involved in traffic crashes. To this end, motorcycle crash data between 2009 and 2012 was extracted from Iran traffic crash database and a logistic regression analysis was performed to obtain odds ratio estimates for each of the study variables. RESULTS: The fatality risk of motorcyclists has a direct relationship with the number of pillion passengers carried. Results also indicate that the amount of increase in the likelihood of having a fatality in a motorcycles crash is considerably higher when the operator is accompanied by a male passenger of the same age. Furthermore, results showed that if the crash is occurred in the darkness, on curves, in rural areas and on highways, then the crash would be more likely to be fatal. Moreover, the head-on collisions, older operators, unlicensed operators and not using a safety helmet were found to increase the likelihood of a fatality in a motorcycle crash. CONCLUSIONS: Preventative measures such as, imposing stricter rules regarding safety helmet usage and confining the number of pillion passengers to one, might be implemented to reduce the fatality risk in motorcycle crashes. In addition, more appropriate infrastructures for penalizing offending motorcyclists could also reduce the frequency of law violations such as not wearing helmet or riding without motorcycle license, which in turn, would result into a reduction in the fatality risk of motorcycle crashes

  14. Severity of road crashes involving pedestrians in Metro Manila, Philippines.

    Science.gov (United States)

    Verzosa, Nina; Miles, Rebecca

    2016-09-01

    Pedestrians are considered as one of the most vulnerable road users in less developed countries (LDCs). Yet, pedestrian safety remains poorly addressed in both urban and rural transportation plans in most LDCs. Since most pedestrian injury severity studies are conducted in developed countries, this study fills the gap with an inquiry focused on a highly urbanized region of an LDC that faces a rapid increase in car ownership and increasing pedestrian-related traffic injuries, documenting specific pedestrian safety issues and providing guidance for injury prevention measures in such places. Using the Metro Manila Accident Reporting and Analysis System (MMARAS) data from 2008 to 2011, this study combines binomial logistic regression and street level analysis that further explores the statistical results and examines other factors that contribute to collisions and increase the potential for serious injury or death in three cities in Metro Manila: Makati, Manila, and Quezon. The results of the binomial regression analysis show that traffic crashes that involve heavy and multiple vehicles, and an elderly pedestrian (60 years old and above), as well as those that occurred during the evening (7 pm to midnight) and late at night (1 am to 5 am) have significantly higher odds of resulting in a fatal outcome; when the crash involves a female pedestrian and when the road surface is wet the odds of a fatal outcome are lower. Moreover, by closely examining the environment of these roadways, the study finds that most pedestrian fatalities occur on high-speed, high-traffic-volume, multilane roadways, that are surrounded by land uses that generate a particularly problematic mix of heavy vehicular and pedestrian traffic. The street level analysis also finds that fatal pedestrian crashes occur close to different types of transit stations. The results of this study of three cities in Metro Manila, reflect the twofold challenge to pedestrian safety in rapidly urbanizing areas in

  15. Anger, Cognition, Ideology: What Crash Can Show Us About Emotion

    Directory of Open Access Journals (Sweden)

    Sue J. Kim

    2010-06-01

    Full Text Available

    Abstract (E: Sue J. Kim’s essay “Anger, Cognition, Ideology: What Crash Can Show Us About Emotion” argues for the relevance and importance of cognitive studies to ethnic and postcolonial literary studies, and vice versa. After surveying recent developments in the field of cognitive studies, the essay combines cultural and cognitive approaches in order to examine anger in and around the 2005 Paul Haggis film Crash.

     

    Abstract (F: Dans cet article, l’auteur fait un plaidoyer pour l’application des études cognitives aux études ethniques et postcoloniales et inversement. L’essai présente d’abord un survol des récents développements dans le domaine des études cognitives, puis combine les approches culturelles et cognitives dans une lecture détaillée du thème de la colère dans le film Crash de Paul Haggis (2005.

     

  16. Case-control analysis in highway safety: Accounting for sites with multiple crashes.

    Science.gov (United States)

    Gross, Frank

    2013-12-01

    There is an increased interest in the use of epidemiological methods in highway safety analysis. The case-control and cohort methods are commonly used in the epidemiological field to identify risk factors and quantify the risk or odds of disease given certain characteristics and factors related to an individual. This same concept can be applied to highway safety where the entity of interest is a roadway segment or intersection (rather than a person) and the risk factors of interest are the operational and geometric characteristics of a given roadway. One criticism of the use of these methods in highway safety is that they have not accounted for the difference between sites with single and multiple crashes. In the medical field, a disease either occurs or it does not; multiple occurrences are generally not an issue. In the highway safety field, it is necessary to evaluate the safety of a given site while accounting for multiple crashes. Otherwise, the analysis may underestimate the safety effects of a given factor. This paper explores the use of the case-control method in highway safety and two variations to account for sites with multiple crashes. Specifically, the paper presents two alternative methods for defining cases in a case-control study and compares the results in a case study. The first alternative defines a separate case for each crash in a given study period, thereby increasing the weight of the associated roadway characteristics in the analysis. The second alternative defines entire crash categories as cases (sites with one crash, sites with two crashes, etc.) and analyzes each group separately in comparison to sites with no crashes. The results are also compared to a "typical" case-control application, where the cases are simply defined as any entity that experiences at least one crash and controls are those entities without a crash in a given period. In a "typical" case-control design, the attributes associated with single-crash segments are weighted

  17. Plane Mercury librations

    Science.gov (United States)

    Barkin, Yu. V.; Ferrandiz, J. M.

    2009-04-01

    theory of Mercury librations in longitude by using three characteristics of Mercury rotation determined in the paper [3]. Two from these parameters are values of angle of librations in longitude and angular velocity in moment of passage of perihelion of Mercury orbit on 17 April 2002: (^g)0 = 0007 ± 0001, (^?•? )0 = (2.10± 0.06)•? ars/d. Third parameter determined in [3] is a dynamical coefficient: K = (B -A)•(4Cm ) = (5.08± 0.30) × 10-5. B > A are principal moment of inertia, corresponding to equatorial axes of inertia; Cm is a polar moment of inertia of the mantle of Mercury. 1 Analytical theory of plane Mercury librations. This theory describes forced and free librations of Mercury in longitude in the frame of plane problem about resonant librations of Mercury considered or as non-spherical rigid body, or as system of rigid non-spherical mantle and liquid ellipsoidal core. Saving the main terms for the perturbations of angle of librations ^g and angular velocity ^? in both mentioned cases we will have formulae [6]: ^g = K(E sin M + E sin2M + E sin 3M + E sin4M + E sin5M ) 1 2 3 4 5+K0 sin(E šKM- - φ) (A)

  18. Utilizing the eigenvectors of freeway loop data spatiotemporal schematic for real time crash prediction.

    Science.gov (United States)

    Fang, Shou'en; Xie, Wenjing; Wang, Junhua; Ragland, David R

    2016-09-01

    The concept of crash precursor identification is gaining more practicality due to the recent advancements in Advanced Transportation Management and Information Systems. Investigating the shortcomings of the existing models, this paper proposes a new method to model the real time crash likelihood based on loop data through schematic eigenvectors. Firstly, traffic volume, occupancy and density spatiotemporal schematics in certain duration before an accident occurrence were constructed to describe the traffic flow status. Secondly, eigenvectors and eigenvalues of the spatiotemporal schematics were extracted to represent traffic volume, occupancy and density situation before the crash occurrence. Thirdly, by setting the vectors in crash time as case and those at crash free time as control, a logistic model is constructed to identify the crash precursors. Results show that both the eigenvectors and eigenvalues can significantly impact the accident likelihood compared to the previous study, the proposed model has the advantage of avoiding multicollinearity, better reflection of the overall traffic flow status before the crash, and improving missing data problem of loop detectors. PMID:27258946

  19. Case series analysis of hindfoot injuries sustained by drivers in frontal motor vehicle crashes.

    Science.gov (United States)

    Ye, Xin; Funk, James; Forbes, Aaron; Hurwitz, Shepard; Shaw, Greg; Crandall, Jeff; Freeth, Rob; Michetti, Chris; Rudd, Rodney; Scarboro, Mark

    2015-09-01

    Improvements to vehicle frontal crashworthiness have led to reductions in toe pan and instrument panel intrusions as well as leg, foot, and ankle loadings in standardized crash tests. Current field data, however, suggests the proportion of foot and ankle injuries sustained by drivers in frontal crashes has not decreased over the past two decades. To explain the inconsistency between crash tests results and real world lower limb injury prevalence, this study investigated the injury causation scenario for the specific hind-foot injury patterns observed in frontal vehicle crashes. Thirty-four cases with leg, foot, and ankle injuries were selected from the Crash Injury Research and Engineering Network (CIREN) database. Talus fractures were present in 20 cases, representing the most frequent hind-foot skeletal injuries observed among the reviewed cases. While axial compression was the predominant loading mechanism causing 18 injuries, 11 injured ankles involved inversion or eversion motion, and 5 involved dorsiflexion as the injury mechanism. Injured ankles of drivers were more biased towards the right aspect with foot pedals contributing to injuries in 13 of the 34 cases. Combined, the results suggest that despite recent advancement of vehicle performance in crash tests, efforts to reduce axial forces sustained in lower extremity should be prioritized. The analysis of injury mechanisms in this study could aid in crash reconstructions and the development of safety systems for vehicles. PMID:26183693

  20. Prioritizing Highway Safety Manual's crash prediction variables using boosted regression trees.

    Science.gov (United States)

    Saha, Dibakar; Alluri, Priyanka; Gan, Albert

    2015-06-01

    The Highway Safety Manual (HSM) recommends using the empirical Bayes (EB) method with locally derived calibration factors to predict an agency's safety performance. However, the data needs for deriving these local calibration factors are significant, requiring very detailed roadway characteristics information. Many of the data variables identified in the HSM are currently unavailable in the states' databases. Moreover, the process of collecting and maintaining all the HSM data variables is cost-prohibitive. Prioritization of the variables based on their impact on crash predictions would, therefore, help to identify influential variables for which data could be collected and maintained for continued updates. This study aims to determine the impact of each independent variable identified in the HSM on crash predictions. A relatively recent data mining approach called boosted regression trees (BRT) is used to investigate the association between the variables and crash predictions. The BRT method can effectively handle different types of predictor variables, identify very complex and non-linear association among variables, and compute variable importance. Five years of crash data from 2008 to 2012 on two urban and suburban facility types, two-lane undivided arterials and four-lane divided arterials, were analyzed for estimating the influence of variables on crash predictions. Variables were found to exhibit non-linear and sometimes complex relationship to predicted crash counts. In addition, only a few variables were found to explain most of the variation in the crash data. PMID:25823903

  1. Injury risk for rear-seated occupants in small overlap crashes.

    Science.gov (United States)

    Arbogast, Kristy B; Locey, Caitlin M; Hammond, Rachel; Belwadi, Aditya

    2013-01-01

    Small overlap crashes, where the primary crash engagement is outboard from the longitudinal energy absorbing structures of the vehicle, have received recent interest as a crash dynamic that results in high likelihood of injury. Previous analyses of good performing vehicles showed that 24% of crashes with AIS 3+ injuries to front seat occupants were small overlap crashes. However, similar evaluations have not been conducted for those rear seated. Vehicle dynamics suggest that rear seat occupants may be at greater risk due to lack of lateral seating support and a steering wheel to hold, making them more sensitive to lateral movement seen in these crashes. Thus, the objective was to calculate injury risk for rear-seated occupants in small overlap collisions. AIS 2+ and AIS 3+ injury risk was calculated from NASS-CDS data from 2000-2011. Inclusion criteria were vehicles of model year 2000 or later, with CDC codes of "FL" or "FR", and an occupant in the second or third row. AIS2+ injury risk was 5.1%, and AIS3+ injury risk was 2.4%. Of note, half of the occupants were Occupants seated near side were nearly three times as likely to sustain an AIS2+ injury than occupants seated far side. Particular attention should be paid to the prominence of head injuries in this crash dynamic and consideration given to their mitigation. Additional research should determine whether countermeasures being implemented for front seat occupants can be beneficial to rear seat occupants. PMID:24406964

  2. Risk factors for severe injury in cyclists involved in traffic crashes in Victoria, Australia.

    Science.gov (United States)

    Boufous, Soufiane; de Rome, Liz; Senserrick, Teresa; Ivers, Rebecca

    2012-11-01

    This study examines the impact of cyclist, road and crash characteristics on the injury severity of cyclists involved in traffic crashes reported to the police in Victoria, Australia between 2004 and 2008. Logistic regression analysis was carried out to identify predictors of severe injury (serious injury and fatality) in cyclist crashes reported to the police. There were 6432 cyclist crashes reported to the police in Victoria between 2004 and 2008 with 2181 (33.9%) resulting in severe injury of the cyclist involved. The multivariate analysis found that factors that increase the risk of severe injury in cyclists involved in traffic crashes were age (50 years and older), not wearing a helmet, riding in the dark on unlit roads, riding on roads zoned 70 km/h or above, on curved sections of the road, in rural locations and being involved in head-on collisions as well as off path crashes, which include losing control of vehicle, and on path crashes which include striking the door of a parked vehicle. While this study did not test effectiveness of preventative measures, policy makers should consider implementation of programs that address these risk factors including helmet programs and environmental modifications such as speed reduction on roads that are frequented by cyclists. PMID:23036419

  3. A Perspective into Regulatory Requirements for Intentional Aircraft Crash

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Yun; Park, Jong Seuk; Chung, Yun Suk [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Kim, Inn Seock [ISSA Technology, Maryland (Korea, Republic of); Choi, Eong Soo; Kim, Jong Hyun [ACT Co., Daejeon (Korea, Republic of)

    2010-10-15

    In the aftermath of the 9/11 terrorist attacks on the United States, there was heightened interest worldwide in protecting nuclear power plants against intentional aircraft attack by terrorists. This paper presents our perspective into regulatory requirements for intentional aircraft crash that were set forth in foreign countries, including the latest rulemaking by the U.S. Nuclear Regulatory Commission (NRC), i.e., 10 CFR 50.54(hh) and 10 CFR 50.150 that have been made effective in May and July of 2009, respectively. In light of these international efforts to further enhance safety of NPPs, a study is also underway at the Korea Institute of Nuclear Safety (KINS) to establish an effective and efficient regulatory approach in consideration of the state of the art in this area

  4. A Perspective into Regulatory Requirements for Intentional Aircraft Crash

    International Nuclear Information System (INIS)

    In the aftermath of the 9/11 terrorist attacks on the United States, there was heightened interest worldwide in protecting nuclear power plants against intentional aircraft attack by terrorists. This paper presents our perspective into regulatory requirements for intentional aircraft crash that were set forth in foreign countries, including the latest rulemaking by the U.S. Nuclear Regulatory Commission (NRC), i.e., 10 CFR 50.54(hh) and 10 CFR 50.150 that have been made effective in May and July of 2009, respectively. In light of these international efforts to further enhance safety of NPPs, a study is also underway at the Korea Institute of Nuclear Safety (KINS) to establish an effective and efficient regulatory approach in consideration of the state of the art in this area

  5. Secondary fast reconnecting instability in the sawtooth crash

    CERN Document Server

    Del Sarto, Daniele

    2016-01-01

    In this work we consider magnetic reconnection in thin current sheets with both resistive and electron inertia effects. When the current sheet is produced by a primary instability of the internal kink type, the analysis of secondary instabilities indicates that reconnection proceeds on a time scale much shorter than the primary instability characteristic time. In the case of a sawtooth crash, non-collisional physics becomes important above a value of the Lundquist number which scales like S ~ (R/d_e)^{12/5}, in terms of the tokamak major radius R and of the electron skin depth d_e. This value is commonly achieved in present day devices. As collisionality is further reduced, the characteristic rate increases, approaching Alfv\\'enic values when the primary instability approaches the collisionless regime.

  6. Automatic Crash Recovery Artifacts From Internet Explorer 8 And 9

    Directory of Open Access Journals (Sweden)

    John Moran

    2012-09-01

    Full Text Available A good portion of today’s investigations include, at least in part, an examination of the user’s web history.Although it has lost ground over the past several years, Microsoft’s Internet Explorer still accounts for a large portion of the web browser market share.Most users are now aware that Internet Explorer will save browsing history, user names, passwords and form history.Consequently some users seek to eliminate these artifacts, leaving less for examiners to discover during investigations.However, most users, and probably a good portion of examiners are unaware Automatic Crash Recovery, can leave a gold mine of recent browsing history in spite of the users attempts to delete historical artifacts.

  7. Crash test for the Copenhagen problem with oblateness

    CERN Document Server

    Zotos, Euaggelos E

    2015-01-01

    The case of the planar circular restricted three-body problem where one of the two primaries is an oblate spheroid is investigated. We conduct a thorough numerical analysis on the phase space mixing by classifying initial conditions of orbits and distinguishing between three types of motion: (i) bounded, (ii) escape and (iii) collisional. The presented outcomes reveal the high complexity of this dynamical system. Furthermore, our numerical analysis shows a strong dependence of the properties of the considered escape basins with the total orbital energy, with a remarkable presence of fractal basin boundaries along all the escape regimes. Interpreting the collisional motion as leaking in the phase space we related our results to both chaotic scattering and the theory of leaking Hamiltonian systems. We also determined the escape and collisional basins and computed the corresponding escape/crash times. The highly fractal basin boundaries observed are related with high sensitivity to initial conditions thus implyi...

  8. Bubble, critical zone and the crash of Royal Ahold

    Science.gov (United States)

    Broekstra, Gerrit; Sornette, Didier; Zhou, Wei-Xing

    2005-02-01

    We find that the seed of the 2002/03 crisis of the Dutch supermarket giant AHOLD was planted in 1996. We have adapted Weidlich's theory of opinion formation to describe the formation of buy or sell decisions among investors, based on a competition between the mechanisms of herding and of personal opinion opposing the herd. Using our identification of a “critical zone” starting in mid-1997 describing the maturation of a systemic instability forewarning of an inevitable crash fueled by raising expectations of investors to maintain strong herding pressures, our study opens the possibility of developing early warning signals but also suggests to top management ways of dealing with the coming crisis.

  9. Aircraft crash analysis of the proposed sizewell B containment vessel

    International Nuclear Information System (INIS)

    This paper attempts to examine the behaviour of the proposed sizewell B containment vessel under the impact of a multi-role combat aircraft such as a Tornado and Phantom RF-4E. A 600 section of the containment vessel is analysed using three dimensional 20 noded isoparametric finite elements adopted in Program CRASH. The impact area under consideration is 28 m2 which is evaluated from the data obtained from these two aircraft. The vessel is assumed to have unbonded tendons both in the dome and in the barrel wall. The influence of the liner is included in evaluating resistance to the impact. A three-dimensional time dependent impact analysis is carried out which incorporates, direct integration concept. The final results obtained include displacements, velocities, accelerations; concrete scabbing, perforation and general cracking. The final damage is shown in a specially prepared post-mortem diagram. The paper has an appendix summarising the constitutive equations for the proposed numerical model. (orig.)

  10. Prescription medicines and the risk of road traffic crashes: a French registry-based study.

    Directory of Open Access Journals (Sweden)

    Ludivine Orriols

    Full Text Available BACKGROUND: In recent decades, increased attention has been focused on the impact of disabilities and medicinal drug use on road safety. The aim of our study was to investigate the association between prescription medicines and the risk of road traffic crashes, and estimate the attributable fraction. METHODS AND FINDINGS: We extracted and matched data from three French nationwide databases: the national health care insurance database, police reports, and the national police database of injurious crashes. Drivers identified by their national health care number involved in an injurious crash in France, between July 2005 and May 2008, were included in the study. Medicines were grouped according to the four risk levels of the French classification system (from 0 [no risk] to 3 [high risk]. We included 72,685 drivers involved in injurious crashes. Users of level 2 (odds ratio [OR]  = 1.31 [1.24-1.40] and level 3 (OR  = 1.25 [1.12-1.40] prescription medicines were at higher risk of being responsible for a crash. The association remained after adjustment for the presence of a long-term chronic disease. The fraction of road traffic crashes attributable to levels 2 and 3 medications was 3.3% [2.7%-3.9%]. A within-person case-crossover analysis showed that drivers were more likely to be exposed to level 3 medications on the crash day than on a control day, 30 days earlier (OR  = 1.15 [1.05-1.27]. CONCLUSION: The use of prescription medicines is associated with a substantial number of road traffic crashes in France. In light of the results, warning messages appear to be relevant for level 2 and 3 medications and questionable for level 1 medications. A follow-up study is needed to evaluate the impact of the warning labeling system on road traffic crash prevention.

  11. Understanding crash mechanism on urban expressways using high-resolution traffic data.

    Science.gov (United States)

    Hossain, Moinul; Muromachi, Yasunori

    2013-08-01

    Urban expressways play a vital role in the modern mega cities by serving peak hour traffic alongside reducing travel time for moderate to long distance intra-city trips. Thus, ensuring safety on these roads holds high priority. Little knowledge has been acquired till date regarding crash mechanism on these roads. This study uses high-resolution traffic data collected from the detectors to identify factors influencing crash. It also identifies traffic patterns associated with different types of crashes and explains crash phenomena thereby. Unlike most of the previous studies on conventional expressways, the research separately investigates the basic freeway segments (BFS) and the ramp areas. The study employs random multinomial logit, a random forest of logit models, to rank the variables; expectation maximization clustering algorithm to identify crash prone traffic patterns and classification and regression trees to explain crash phenomena. As accentuated by the study outcome, crash mechanism is not generic throughout the expressway and it varies from the BFS to the ramp vicinities. The level of congestion and speed difference between upstream and downstream traffic best explains crashes and their types for the BFS, whereas, the ramp flow has the highest influence in determining the types of crashes within the ramp vicinities. The paper also discusses about the applicability of different countermeasures, such as, variable speed limits, temporary restriction on lane changing, posting warnings, etc., to attenuate different patterns of hazardous traffic conditions. The study outcome can be utilized in designing location and traffic condition specific proactive road safety management systems for urban expressways. PMID:23628939

  12. Hotspots and social background of urban traffic crashes: A case study in Cluj-Napoca (Romania).

    Science.gov (United States)

    Benedek, József; Ciobanu, Silviu Marian; Man, Titus Cristian

    2016-02-01

    Mobility practices have changed dramatically in Romanian towns over the last 25 years, following the collapse of socialist mobility restrictions. Urban areas like Cluj-Napoca are facing both increasing immigration and car mobility, and therefore increasing levels of road traffic crashes. The analysis of traffic crashes is one of the most important elements for improving the road safety policy. This paper is divided in two parts. In the first one, the authors focus on identifying the traffic crash hotspots along the street network, while in the second part they discuss the social background of road traffic crash occurrence. The first step in analyzing traffic crashes is to determine crash hotspots. A four-year record (2010-2013) provided by the Traffic Department of the General Inspectorate of Romanian Police (GIRPTD) was used. As a method of hotspot determination, the Kernel Density Estimation tool was employed, in the frame of the spatial analysis along network (SANET). The outcome was the hotspot map of traffic crashes in Cluj-Napoca. The results have revealed 4 categories of street segments: not-dangerous, low-dangerous, medium-dangerous and high-dangerous. Based on this classification, at least 4 dangerous areas were identified, located at the city entrances-exits (in the West, North-West and East) and the city center (the most dangerous zone). The second part of the paper focuses on social groups involved in car crashes. The following are considered: age, gender and blood alcohol concentration of the person (driver or pedestrian) found guilty for every individual crash. PMID:26680130

  13. Analysis of factors associated with injury severity in crashes involving young New Zealand drivers.

    Science.gov (United States)

    Weiss, Harold B; Kaplan, Sigal; Prato, Carlo G

    2014-04-01

    Young people are a risk to themselves and other road users, as motor vehicle crashes are the leading cause of their death. A thorough understanding of the most important factors associated with injury severity in crashes involving young drivers is important for designing well-targeted restrictive measures within youth-oriented road safety programs. The current study estimates discrete choice models of injury severity of crashes involving young drivers conditional on these crashes having occurred. The analysis examined a comprehensive set of single-vehicle and two-vehicle crashes involving at least one 15-24 year-old driver in New Zealand between 2002 and 2011 that resulted in minor, serious or fatal injuries. A mixed logit model accounting for heterogeneity and heteroscedasticity in the propensity to injury severity outcomes and for correlation between serious and fatal injuries proved a better fit than a binary and a generalized ordered logit. Results show that the young drivers' behavior, the presence of passengers and the involvement of vulnerable road users were the most relevant factors associated with higher injury severity in both single-vehicle and two-vehicle crashes. Seatbelt non-use, inexperience and alcohol use were the deadliest behavioral factors in single-vehicle crashes, while fatigue, reckless driving and seatbelt non-use were the deadliest factors in two-vehicle crashes. The presence of passengers in the young drivers' vehicle, and in particular a combination of males and females, dramatically increased the probability of serious and fatal injuries. The involvement of vulnerable road users, in particular on rural highways and open roads, considerably amplified the probability of higher crash injury severity. PMID:24456849

  14. Safety impacts of SUVs, vans, and pickup trucks in two-vehicle crashes.

    Science.gov (United States)

    Toy, Edmond L; Hammitt, James K

    2003-08-01

    Policy makers, vehicle manufacturers, and consumers have shown growing concern about the relative safety of sport utility vehicles (SUVs), vans, pickups, and cars. Empirical analysis of real-world crashes is complicated by the possibility that apparent relationships between vehicle type and safety may be confounded by other factors, such as driver behavior and crash circumstances. This study compares different vehicle types with respect to their crashworthiness (self-protection) and aggressivity (risk to others) in crashes between two passenger vehicles. The U.S. Crashworthiness Data System is used to analyze detailed information on 6,481 drivers involved in crashes during 1993-1999. Logistic regression analysis is used to model the risk of serious injury or death to a driver, conditional on a crash occurring. Covariates include the body type of each vehicle in the crash; the driver's age, gender, and restraint use; and the configuration of the crash. A unique feature of this study is the use of "delta-v" to represent the joint effects of vehicle mass and crash severity. While estimated effects are somewhat sensitive to the injury severity level used as the outcome variable, SUVs, vans, and pickups appear to be more aggressive and may be more crashworthy than cars. Effects of pickups are most pronounced. Drivers in pickups face less risk of serious injury than car drivers (odds ratio [OR], 0.35; 95% confidence interval [CI], 0.20-0.60), and drivers who collide with pickups experience more than twice the risk than those who collide with a car (OR, 2.18; 95% CI, 1.03-4.62). While vehicle mass and crash severity contribute to the apparent crashworthiness and aggressivity of passenger vehicles, other vehicle characteristics associated with body type (e.g., the stiffness and height of the underlying structure of the vehicle) also influence safety risks. PMID:12926558

  15. Requirements of a system to reduce car-to-vulnerable road user crashes in urban intersections.

    Science.gov (United States)

    Habibovic, Azra; Davidsson, Johan

    2011-07-01

    Intersection crashes between cars and vulnerable road users (VRUs), such as pedestrians and bicyclists, often result in injuries and fatalities. Advanced driver assistance systems (ADASs) can prevent, or mitigate, these crashes. To derive functional requirements for such systems, an understanding of the underlying contributing factors and the context in which the crashes occur is essential. The aim of this study is to use microscopic and macroscopic crash data to explore the potential of information and warning providing ADASs, and then to derive functional sensor, collision detection, and human-machine interface (HMI) requirements. The microscopic data were obtained from the European project SafetyNet. Causation charts describing contributing factors for 60 car-to-VRU crashes had been compiled and were then also aggregated using the SafetyNet Accident Causation System (SNACS). The macroscopic data were obtained from the Swedish national crash database, STRADA. A total of 9702 crashes were analyzed. The results show that the most frequent contributing factor to the crashes was the drivers' failure to observe VRUs due to reduced visibility, reduced awareness, and/or insufficient comprehension. An ADAS should therefore help drivers to observe the VRUs in time and to enhance their ability to interpret the development of events in the near future. The system should include a combination of imminent and cautionary collision warnings, with additional support in the form of information about intersection geometry and traffic regulations. The warnings should be deployed via an in-vehicle HMI and according to the likelihood of crash risk. The system should be able to operate under a variety of weather and light conditions. It should have the capacity to support drivers when their view is obstructed by physical objects. To address problems that vehicle-based sensors may face in this regard, the use of cooperative systems is recommended. PMID:21545892

  16. Hot-Air Balloon Tours: Crash Epidemiology in the United States, 2000-2011

    Science.gov (United States)

    Ballard, Sarah-Blythe; Beaty, Leland P.; Baker, Susan P.

    2016-01-01

    Introduction Hot-air balloon tours are FAR Part 91-governed balloon rides conducted for compensation or hire. Part 91, General Aviation, in general involves the least strict federal regulations and accounts for the majority of aviation crashes and fatalities. Methods National Transportation Safety Board reports of hot-air balloon tour crashes in the United States from 2000 through 2011 were read and analyzed. Results During the 12-yr period, 78 hot-air balloon tours crashed, involving 518 occupants. There were 91 serious injuries and 5 fatalities; 83% of crashes resulted in one or more serious or fatal outcomes. Of the serious injuries characterized, 56% were lower extremity fractures. Most crashes (81%) occurred during landing; 65% involved hard landings. Fixed object collisions contributed to 50% of serious injuries and all 5 fatalities. During landing sequences, gondola dragging, tipping, bouncing, and occupant ejection were associated with poor outcomes. Of the crashes resulting in serious or fatal outcomes, 20% of balloons were significantly damaged or destroyed. Discussion The incidence of morbidity and mortality is high among hot-air balloon tour crashes, and the proportion of balloon crashes attributed to paid rides appears to have increased over time. In addition to examining the role of restraint systems, personal protective equipment, and power line emergency procedures in ballooning, injury prevention efforts should target factors such hard landings, object strikes, gondola instability, and occupant ejections, which are associated with balloon injuries and deaths. Crash outcomes may also improve with vehicle engineering that enables balloons themselves to absorb impact forces. PMID:24279231

  17. Assessment of methodologies for analysis of the dungeness B accidental aircraft crash risk.

    Energy Technology Data Exchange (ETDEWEB)

    LaChance, Jeffrey L.; Hansen, Clifford W.

    2010-09-01

    The Health and Safety Executive (HSE) has requested Sandia National Laboratories (SNL) to review the aircraft crash methodology for nuclear facilities that are being used in the United Kingdom (UK). The scope of the work included a review of one method utilized in the UK for assessing the potential for accidental airplane crashes into nuclear facilities (Task 1) and a comparison of the UK methodology against similar International Atomic Energy Agency (IAEA), United States (US) Department of Energy (DOE), and the US Nuclear Regulatory Commission (NRC) methods (Task 2). Based on the conclusions from Tasks 1 and 2, an additional Task 3 would provide an assessment of a site-specific crash frequency for the Dungeness B facility using one of the other methodologies. This report documents the results of Task 2. The comparison of the different methods was performed for the three primary contributors to aircraft crash risk at the Dungeness B site: airfield related crashes, crashes below airways, and background crashes. The methods and data specified in each methodology were compared for each of these risk contributors, differences in the methodologies were identified, and the importance of these differences was qualitatively and quantitatively assessed. The bases for each of the methods and the data used were considered in this assessment process. A comparison of the treatment of the consequences of the aircraft crashes was not included in this assessment because the frequency of crashes into critical structures is currently low based on the existing Dungeness B assessment. Although the comparison found substantial differences between the UK and the three alternative methodologies (IAEA, NRC, and DOE) this assessment concludes that use of any of these alternative methodologies would not change the conclusions reached for the Dungeness B site. Performance of Task 3 is thus not recommended.

  18. Fatal motorcycle crashes: a serious public health problem in Brazil

    Directory of Open Access Journals (Sweden)

    Carrasco Carlos

    2012-08-01

    Full Text Available Abstract Introduction The numbers of two-wheel vehicles are growing across the world. In comparison to other vehicles, motorcycles are cheaper and thus represent a significant part of the automobile market. Both the mobility and speed are attractive factors to those who want to use them for work or leisure. Crashes involving motorcyclists have become an important issue, especially fatal ones. Specific severe injuries are responsible for the deaths. Defining them is necessary in order to offer better prevention and a more suitable medical approach. Methods All fatal motorcycle crashes between January 2001 and December 2009 in Campinas, Brazil, were analyzed in this study. Official data have been collected from police incident reports, hospitals’ registers and autopsies. Both incidents and casualties were analyzed according to relevant variables. The Injury Severity Score (ISS was calculated, describing the most potentially fatal injuries. Results There were 479 deaths; 90.8% were male; the mean age was 27.8 (range 0-73; 86.4% were conductors of the vehicles; blood alcohol was positive in 42.3%; 49.7% died at a hospital; 32.6% died at the scene; 26.1% of the accidents occurred at night, 69.1% were urban and 30.9% occurred on highways. The main causes of injury were collisions (63% and falls (14%. The mean ISS was 38.5 (range 9-75. With regard to injuries, head trauma (67% and thoracic trauma (40% were the most common, followed by abdominal trauma (35%. Traumatic brain injury (67% and hypovolemic shock (38% were the most frequent causes of death. Conclusions Alcohol was a significant factor in relation to the accidents. Head trauma was the most frequent and severe injury. Half of the victims died before receiving adequate medical attention, suggesting that prevention programs and laws should be implemented and applied in order to save future lives.

  19. Nuclear containment structure subjected to commercial and fighter aircraft crash

    International Nuclear Information System (INIS)

    Highlights: • Nuclear containment response has been studied against aircraft crash. • Concrete damaged plasticity and Johnson–Cook elasto-viscoplastic models were employed. • Boeing 747-400 and Boeing 767-400 aircrafts caused global failure of containment. • Airbus A320 and Boeing 707-320 aircrafts caused local damage. • Tension damage of concrete was found more prominent compared to compression damage. -- Abstract: The response of a boiling water reactor (BWR) nuclear containment vessel has been studied against commercial and fighter aircraft crash using a nonlinear finite element code ABAQUS. The aircrafts employed were Boeing 747-400, Boeing 767-400, Airbus A-320, Boeing 707-320 and Phantom F4. The containment was modeled as a three-dimensional deformable reinforced concrete structure while the loading of aircraft was assigned using the respective reaction–time curve. The location of strike was considered near the junction of dome and cylinder, and the angle of incidence, normal to the containment surface. The material behavior of the concrete was incorporated using the damaged plasticity model while that of the reinforcement, the Johnson–Cook elasto-viscoplastic model. The containment could not sustain the impact of Boeing 747-400 and Boeing 767-400 aircrafts and suffered rupture of concrete around the impact region leading to global failure. On the other hand, the maximum local deformation at the point of impact was found to be 0.998 m, 0.099 m, 0.092 m, 0.089 m, and 0.074 m against Boeing 747-400, Phantom F4, Boeing 767, Boeing 707-320 and Airbus A-320 aircrafts respectively. The results of the present study were compared with those of the previous analytical and numerical investigations with respect to the maximum deformation and overall behavior of the containment

  20. Nuclear containment structure subjected to commercial and fighter aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Sadique, M.R., E-mail: rehan.sadique@gmail.com; Iqbal, M.A., E-mail: iqbalfce@iitr.ernet.in; Bhargava, P., E-mail: bhpdpfce@iitr.ernet.in

    2013-07-15

    Highlights: • Nuclear containment response has been studied against aircraft crash. • Concrete damaged plasticity and Johnson–Cook elasto-viscoplastic models were employed. • Boeing 747-400 and Boeing 767-400 aircrafts caused global failure of containment. • Airbus A320 and Boeing 707-320 aircrafts caused local damage. • Tension damage of concrete was found more prominent compared to compression damage. -- Abstract: The response of a boiling water reactor (BWR) nuclear containment vessel has been studied against commercial and fighter aircraft crash using a nonlinear finite element code ABAQUS. The aircrafts employed were Boeing 747-400, Boeing 767-400, Airbus A-320, Boeing 707-320 and Phantom F4. The containment was modeled as a three-dimensional deformable reinforced concrete structure while the loading of aircraft was assigned using the respective reaction–time curve. The location of strike was considered near the junction of dome and cylinder, and the angle of incidence, normal to the containment surface. The material behavior of the concrete was incorporated using the damaged plasticity model while that of the reinforcement, the Johnson–Cook elasto-viscoplastic model. The containment could not sustain the impact of Boeing 747-400 and Boeing 767-400 aircrafts and suffered rupture of concrete around the impact region leading to global failure. On the other hand, the maximum local deformation at the point of impact was found to be 0.998 m, 0.099 m, 0.092 m, 0.089 m, and 0.074 m against Boeing 747-400, Phantom F4, Boeing 767, Boeing 707-320 and Airbus A-320 aircrafts respectively. The results of the present study were compared with those of the previous analytical and numerical investigations with respect to the maximum deformation and overall behavior of the containment.

  1. Numerical simulation of aircraft crash on nuclear containment structure

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, M.A., E-mail: iqbalfce@iitr.ernet.in [Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee 247667 (India); Rai, S.; Sadique, M.R.; Bhargava, P. [Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee 247667 (India)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer The deformation was more localised at the center of cylindrical portion. Black-Right-Pointing-Pointer The peak deflection at the junction of dome and cylinder was found to be 67 mm. Black-Right-Pointing-Pointer The peak deflection at midpoint of the cylindrical portion was found to be 88.9 mm. Black-Right-Pointing-Pointer The strain rate was found to be an important parameter to effect the deformation. Black-Right-Pointing-Pointer The model without strain rate and 290 s{sup -1} strain rate predicted very high deformations. - Abstract: Numerical simulations were carried with ABAQUS/Explicit finite element code in order to predict the response of BWR Mark III type nuclear containment against Boeing 707-320 aircraft crash. The load of the aircraft was applied using and force history curve. The damaged plasticity model was used to predict the behavior of concrete while the Johnson-Cook elasto-viscoplastic material model was used to incorporate the behavior of steel reinforcement. The crash was considered to occur at two different locations i.e., the midpoint of the cylindrical portion and the junction of dome and cylinder. The midpoint of the cylindrical portion experienced more deformation. The strain rate in the material model was varied and found to have a significant effect on the response of containment. The results of the present investigation were compared with those of the studies available in literature and a close agreement with the previous results was found in terms of maximum target deformation.

  2. Experimental studies on the axial crash behavior of aluminum foam-filled hat sections

    Institute of Scientific and Technical Information of China (English)

    WANG Qing-chun; FAN Zi-jie; GUI Liang-jin; WANG Zheng-hong; FU Zi-lai

    2006-01-01

    Drop hammer tests were carried out to study the axial crash behavior of aluminum foam-filled hat sections.First,the axial crash tests of the empty hat sections,aluminum foam and the aluminum foam-filled hat sections were carried out;then,based upon the test results,the axial crash behavior of the aluminum foam-filled hat sections were analyzed.It was found that aluminum foam filling can increase the energy absorption capacities of the hat sections.Compared with the non-filled structures,aluminum foamfilled structures were much more stable and needed less mass to absorb the specified energy.

  3. The Role of High Frequency Trading in Market Volatility and Flash Crashes

    OpenAIRE

    Ngosa, Abigail

    2015-01-01

    High Frequency Trading is a phenomenon that is yet to be completely understood. This research attempts to find the relationship if any between high frequency trading and volatility as well as the relationship between volatility and flash crashes. A lot of empirical evidence has been carried out on high frequency trading since the infamous Flash Crash of May 6th 2010 with an array of conflicting results. Despite this, the question as to how HFT affects volatility and flash crashes is yet to be...

  4. International Evidence on Market Linkages After the 2008 Stock Market Crash

    OpenAIRE

    Gulser Meric; Christine Lentz; Wayne Smeltz; Ilhan Meric,

    2012-01-01

    The 2008 crash was the most important global stock market crash in history since the Great Depression. In this paper, we study the contemporaneous co-movements of and the time-series lead/lag linkages between global stock markets after the 2008 stock market crash by using the time-varying correlation analysis, principal components analysis (PCA), and Granger-causality (G-C) statistical techniques. We find that correlation between global stock markets has increased and the benefit of global po...

  5. The impact of crash simulation on productivity and problem-solving in automotive R&D

    OpenAIRE

    Spethmann, Philipp; Thomke, Stefan H.; Herstatt, Cornelius

    2006-01-01

    This paper analyzes the impact of the virtual tool 'crash simulation' on automotive R&D over the last 35 years. The research carried out in this context identifies and investigates distinct phases respectively stages of the potential of crash simulations based on the Finite Element Method and the stages' impact on automotive R&D in-depth. In a study of German Original Equipment Manufacturers' (OEM) utilization of crash simulations, the evolution of this tool is explored and its impact on prod...

  6. Vehicle mass and injury risk in two-car crashes: A novel methodology

    OpenAIRE

    R. Tolouei; Maher, M.; Titheridge, H.

    2013-01-01

    This paper introduces a novel methodology based on disaggregate analysis of two-car crash data to estimate the partial effects of mass, through the velocity change, on absolute driver injury risk in each of the vehicles involved in the crash when absolute injury risk is defined as the probability of injury when the vehicle is involved in a two-car crash. The novel aspect of the introduced methodology is in providing a solution to the issue of lack of data on the speed of vehicles prior to the...

  7. Gravitational Couplings for Gop-Planes and y-Op-Planes

    CERN Document Server

    Ospina-Giraldo, J F

    2000-01-01

    The Wess-Zumino actions for generalized orientifold planes (GOp-planes) and y-deformed orientifold planes (yOp-planes) are presented and two series power expantions are realized from whiches processes that involves GOp-planes,yOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard GOp-planes and y-Op-planes are showed.

  8. Conceptual Design of Wave Plane

    DEFF Research Database (Denmark)

    Frigaard, Peter; Trewers, Andrew; Kofoed, Jens Peter;

    The Wave Plane is a patented Wave Energy device of the overtopping type, designed to capture potential as well as kinetic energy. This is as such different to other overtopping devices, who usually only focus on potential energy. If Wave Plane A/S can deliver the turbine technology to utilize both...

  9. Analysis of Casualty Risk per Police-Reported Crash for Model Year 2000 to 2004 Vehicles, using Crash Data from Five States

    Energy Technology Data Exchange (ETDEWEB)

    Wenzel, Tom

    2011-03-20

    In this report we compare two measures of driver risks: fatality risk per vehicle registration-year, and casualty (fatality plus serious injury) risk per police-reported crash. Our analysis is based on three sets of data from five states (Florida, Illinois, Maryland, Missouri, and Pennsylvania): data on all police-reported crashes involving model year 2000 to 2004 vehicles; 2005 county-level vehicle registration data by vehicle model year and make/model; and odometer readings from vehicle emission inspection and maintenance (I/M) programs conducted in urban areas of four of the five states (Florida does not have an I/M program). The two measures of risk could differ for three reasons: casualty risks are different from fatality risk; risks per vehicle registration-year are different from risks per crash; and risks estimated from national data are different from risks from the five states analyzed here. We also examined the effect of driver behavior, crash location, and general vehicle design on risk, as well as sources of potential bias in using the crash data from five states.

  10. A dynamic mathematical test of international property securities bubbles and crashes

    Science.gov (United States)

    Hui, Eddie C. M.; Zheng, Xian; Wang, Hui

    2010-04-01

    This study investigates property securities bubbles and crashes by using a dynamic mathematical methodology developed from the previous research (Watanabe et al. 2007a, b [31,32]). The improved model is used to detect the bubble and crash periods in five international countries/cities (namely, United States, United Kingdom, Japan, Hong Kong and Singapore) from Jan, 2000 to Oct, 2008. By this model definition, we are able to detect the beginning of each bubble period even before it bursts. Meanwhile, the empirical results show that most of property securities markets experienced bubble periods between 2003 and 2007, and crashes happened in Apr 2008 triggered by the Subprime Mortgage Crisis of US. In contrast, Japan suffered the shortest bubble period and no evidence has documented the existence of crash there.

  11. An Inferential System for Determination of Candidate Crash Sites for Search and Rescue Operations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop, test, and prove the feasibility of a methodology for an inferential system for the generation of crash site likelihood maps. These maps will...

  12. The impact of pedestal turbulence and electron inertia on edge-localized-mode crashes

    Energy Technology Data Exchange (ETDEWEB)

    Xi, P. W. [FSC and State Key Lab of Nuclear Physics and Technology, Department of Physics, Peking University, Beijing 100871 (China); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Xu, X. Q. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon (Korea, Republic of); Center for Astrophysics and Space Sciences and Department of Physics, University of California San Diego, La Jolla, California 92093-0429 (United States)

    2014-05-15

    We demonstrate that the occurrence of Edge-Localized-Modes (ELM) crashes does not depend only on the linear peeling-ballooning threshold, but also relies on nonlinear processes. Wave-wave interaction constrains the growth time of a mode, thus inducing a shift in the criterion for triggering an ELM crash. An ELM crash requires the P-B growth rate to exceed a critical value γ>γ{sub c}, where γ{sub c} is set by 1/τ{sup ¯}{sub c}, and τ{sup ¯}{sub c} is the averaged mode phase coherence time. For 0<γ<γ{sub c}, P-B turbulence develops but drives enhanced turbulent transport. We also show that electron inertia dramatically changes the instability threshold when density is low. However, P-B turbulence alone cannot generate enough current transport to allow fast reconnection during an ELM crash.

  13. How Common are Noise Sources on the Crash Arc of Malaysian Flight 370

    Energy Technology Data Exchange (ETDEWEB)

    Fenimore, Edward E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kunkle, Thomas David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stead, Richard J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-10-21

    Malaysian Flight 370 disappeared nearly without a trace. Besides some communication handshakes to the INMASAT satellite, the Comprehensive Test Ban Treaty monitoring system could have heard the aircraft crash into the southern Indian Ocean. One noise event from Cape Leeuwin has been suggested by Stead as the crash and occurs within the crash location suggested by Kunkle at el. We analyze the hydrophone data from Cape Leeuwin to understand how common such noise events are on the arc of possible locations where Malaysian Flight 370 might have crashed. Few other noise sources were found on the arc. The noise event found by Stead is the strongest. No noise events are seen within the Australian Transportation Safety Board (ATSB) new search location until the 10th strongest event, an event which is very close to the noise level.

  14. U.S. Car Crash Deaths Down, but Still Surpass Other Nations

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159736.html U.S. Car Crash Deaths Down, But Still Surpass Other ... roadway death rate among 20 countries examined, the U.S. Centers for Disease Control and Prevention said. "It ...

  15. The analysis of epidemiological characteristics of road traffic crashes in a mountain city in western China

    Institute of Scientific and Technical Information of China (English)

    周继红; 赵新才; 王正国; 朱佩芳; 简华刚; 刘大维; 周金玲; 刘蕾

    2003-01-01

    Objective: To study the epidemiological characteristics and preventive methods of road traffic crashes in a mountain city in western China through sampling investigation of traffic crashes in different regions of Chongqing city in recent years. Methods: Two police teams of traffic management in downtown, two teams in suburb, one team in county and one freeway team were randomly selected, and road traffic crashes between 1988 and 1997 were investigated and analyzed. Results: A total of 13121 road traffic crashes with 6201 crashes with casualties were analyzed. The incidence of crashes was higher in May, June and July, and on Friday and Wednesday and at 8:00-12:00 and 14:00-18:00 within a day. Casualties were 44.0% in pedestrians and 42.5% in passengers of total casualties. The deaths and severe injuries in pedestrians were59.1% of total deaths and 56.4% of total severe injuries. The age of drivers and passengers were mainly at 18-30 years, followed by 31-40 years. People over 60 years old accounted for 24.1% of total pedestrian casualty. Head injury was the most common reason for deaths. The main reasons for these crashes were improper driving and violating traffic laws. Violating traffic laws by pedestrian was one of the main reasons for pedestrian casualty. Conclusions: The crashes are related to the characteristics of geography, climate, society activity of people, and the sense of traffic safety, the basic traffic construction and management in Chongqing. The traffic casualty of pedestrian is a big problem in Chongqing. To prevent and decrease road traffic injuries effective methods should be worked out and propaganda on traffic safety and traffic management should be strengthened according to different characteristics of different regions. To strengthen the first aid and treatment of cranium-brain injury and chest-back injury is also helpful in decreasing traffic deaths.

  16. Motor vehicle crashes and maternal mortality in New Mexico: the significance of seat belt use.

    OpenAIRE

    Schiff, M; Albers, L.; McFeeley, P

    1997-01-01

    In recent years, as deaths from medical complications during pregnancy have declined, injuries-specifically those sustained in motor vehicle crashes-represent a growing proportion of all pregnancy-associated deaths. To investigate pregnancy-associated deaths in motor vehicle crashes in New Mexico, we scrutinized the database of the New Mexico Office of the Medical Investigator for all deaths during pregnancy and up to 6 weeks postpartum from 1986 through 1995. A total of 97 deaths were identi...

  17. Associating crash avoidance maneuvers with driver attributes and accident characteristics: a mixed logit model approach

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    logit model that represents the selection among 5 emergencylateral and speed control maneuvers (i.e., “no avoidance maneuvers,” “braking,” “steering,” “braking and steering,” and“other maneuvers) while accommodating correlations across maneuvers and heteroscedasticity. Data for the analysis were...... rethinking in-vehicle collision warning systems. Future research should address the effectiveness of crash avoidance maneuvers and joint modeling of maneuver selection and crash severity....

  18. Identification of Energy Distribution for Crash Deformational Processes of Road Vehicles

    OpenAIRE

    István Harmati; Péter Várlaki

    2007-01-01

    Car body deformation modelling plays a very important role in crash accidentanalyses, as well as in safe car body design. The determination of the energy absorbed bythe deformation and the corresponding Energy Equivalent Speed can be of key importance;however their precise determination is a very difficult task. Although, using the results ofcrash tests, intelligent and soft methods offer an automatic way to model the crash processitself, as well as to determine the absorbed energy, the befor...

  19. Responsibility Study: Main Illicit Psychoactive Substances Among Car Drivers Involved in Fatal Road Crashes

    OpenAIRE

    Gadegbeku, B.; Amoros, E.; Laumon, B.

    2011-01-01

    In 1999, in France, before considering modifications in drug legislation, the government requested a study of the effect of illicit drugs on the risk of road crashes. It implemented a systematic screening of illicit drugs for all drivers involved in fatal crashes between October 2001 and September 2003. Within the European DRUID project, the study was restricted to car drivers. The project reported here is a responsibility analysis and, as such, it belongs to the framework of case-control stu...

  20. Reconstruction of Car-Electric Bicycle Side Collision Based on PC-Crash

    OpenAIRE

    Shenchao Wang; Yubin Qian; Xianguo Qu

    2014-01-01

    A collision model, an automobile model and a multi-rigid-body model in PC-crash are analyzed. By simulating a side collision accident between a car and an electric bicycle (EB), a method that reproduces the car-electric bicycle side collision accident based on PC-crash is presented according to some important information such as the final position, the contacting location between the cyclist and the car. A result is obtained by comparing with the reproduced result, the defor...

  1. Investor Recognition of Bankrputcy Costs: Evidence from the 1987 Market Crash

    OpenAIRE

    Cheol S. Eun; H. Jonathan Jang

    2000-01-01

    In this paper, we examine the behavior of stock prices of individual firms with different bond ratings surrounding the October market crash of 1987 and therefrom make inferences about the significance of bankruptcy costs borne by stockholders. The key findings are as follows: Immediately following the crash, stock prices of firms with different bond ratings display dramatically divergent behavior. Specifically, stocks with speculative bond ratings exhibit significantly negative cumulative abn...

  2. Onset of a Declining Trend in Fatal Motor Vehicle Crashes Involving Drunk-driving in Japan

    OpenAIRE

    ,

    2013-01-01

    Background In Japan, introduction of severe drunk-driving penalties and a lower blood alcohol concentration (BAC) limit in June 2002 was followed by a substantial reduction in fatal alcohol-related crashes. However, previous research suggests that this reduction started before the legal amendments. The causes of the decrease have not been studied in detail. Methods Monthly police data on fatal road traffic crashes from January 1995 to August 2006 were analyzed using a joinpoint regression mod...

  3. House-price crash and macroeconomic crisis: a Hong Kong case study

    OpenAIRE

    Zhang, Hewitt; Hu, Yannan; Hu, Bo

    2012-01-01

    The crash of house prices has become an important feature of macroeconomic crisis. We argue that the crash of house prices driven by contractionary monetary policy is not only a reaction, but also accelerates and amplifies the fluctuations of major macroeconomic variables. The impulse response of consumption to the house price shock estimated from Bayesian VAR is of same level as that of investment in Hong Kong, which is distinct from the United States. Therefore, in this paper we conduct a c...

  4. Co-Movements of European Equity Markets Before and After the 1987 Crash

    OpenAIRE

    Ilhan Meric,; Gulser Meric

    1997-01-01

    This article studies the changes in the co-movements of the twelve largest European equity markets after the 1987 international equity market crash. Tests based on Box M and principal component analysis indicate that the comovements of these equity markets changed significantly after the crash. Low correlations among national equity markets are often presented as evidence in support of the benefits of international portfolio diversification. The findings indicate that correlations among the t...

  5. Crash Aversion and the Cross-Section of Expected Stock Returns Worldwide

    OpenAIRE

    Weigert, Florian

    2013-01-01

    This paper examines whether investors receive a compensation for holding stocks with a strong sensitivity to extreme market downturns in a sample covering 40 different countries. Worldwide, stocks with strong crash sensitivity deliver average returns of more than 7% p.a. higher than stocks with weak crash sensitivity. The effect is robust across geographical subsamples and is not explained by systematic risk factors and alternative firm characteristics. I show that the risk premium is particu...

  6. Crash Aversion and the Cross-Section of Expected Stock Returns Worldwide

    OpenAIRE

    Weigert, Florian

    2016-01-01

    This paper examines whether investors receive compensation for holding stocks with a strong sensitivity to extreme market downturns in a sample covering forty countries. Worldwide, stocks with strong crash sensitivity deliver average returns of more than 7% p.a. higher than stocks with weak crash sensitivity. The effect is robust across geographical subsamples and is not explained by systematic risk factors and alternative firm characteristics. I show that the risk premium is particularly pro...

  7. Fatal car crash configurations and injury panorama : with special emphasis on the function of restraint system

    OpenAIRE

    Lindquist, Mats

    2007-01-01

    Background: Most traffic safety research projects require accurate real world data which is collected in different databases around the world. This is especially important since the results of these projects form the basis for new crash test procedures and standards. In many of these databases the involvement of the frontal structures of the car in frontal crashes is coded by using the SAE J224 practice (Society of Automobile Engineers). There were indications that by using this practice the ...

  8. The epidemiology of fatal cyclist crashes over a 14-year period in Alberta, Canada

    OpenAIRE

    Gaudet, Lindsay; Romanow, Nicole T. R.; Nettel-Aguirre, Alberto; Voaklander, Donald; Hagel, Brent E.; Rowe, Brian H

    2015-01-01

    Background Cycling is a popular recreational activity and a common transportation option; however, cycling-related injuries can be fatal. There are few studies of cycling fatalities in Canada and none in a region as sparsely populated as Alberta. Methods A chart review was conducted of cyclists involved in fatal crashes. Charts for deaths that occurred between 1998 and 2011 (inclusive) were identified and abstracted onto standardized forms. Personal characteristics and crash circumstances, in...

  9. Car crash and injury among young drivers: contribution of social, circumstantial and car attributes.

    Science.gov (United States)

    Laflamme, L; Vaez, M

    2007-03-01

    The objective of the study was to assess the independent contribution of individual, car and circumstantial features in severe and fatal car crashes involving young drivers. A prospective longitudinal, register-based cohort study was conducted at national level (in Sweden), in which people born in the years 1970-1972 (n = 334070) were followed up for the period 1988-2000 (aged 16-18 years in 1988) for their first two-car crashes leading to severe or fatal injury. Ten variables descriptive of the driver (sociodemographics), the car (safety level) and the crash have been analysed using multiple logistic regressions for male and female drivers separately, compiling crude and adjusted odds ratios with 95% CI. When controlling for other features, none of the variables descriptive of male and female drivers' socio-demographic characteristics impacts significantly on the odds of being severely injured or dying in a car-to-car crash. After adjustment, significant excess risks are observed for speed limits higher than the lowest one, type of crash other than rear end collision and road and light conditions other than favourable (dry and daylight), for both male and female drivers. For males only, cars from all car safety levels have significantly higher odds than those from the safest category. Among male and female young drivers, class differences in the risk of being severely injured in a traffic injury are substantial. Yet, despite this imbalance, crash characteristics (for males and females) and safety level of the vehicle driven (for males) remain the most determinant factors of crash severity. Understanding the social patterning of road traffic injuries is a challenge for public health and it seems that qualitative and quantitative differences in crash exposure offer part of the explanation. Young drivers from all social groups need, however, to be sensitized to the risk factors. PMID:17624005

  10. Occupant injury in rollover crashes - Contribution of planar impacts with objects and other vehicles.

    Science.gov (United States)

    Ivarsson, Johan; Poplin, Gerald; McMurry, Tim; Crandall, Jeff; Kerrigan, Jason

    2015-12-01

    Planar impacts with objects and other vehicles may increase the risk and severity of injury in rollover crashes. The current study compares the frequency of injury measures (MAIS 2+, 3+, and 4+; fatal; AIS 2+ head and cervical spine; and AIS 3+ head and thorax) as well as vehicle type distribution (passenger car, SUV, van, and light truck), crash kinematics, and occupant demographics between single vehicle single event rollovers (SV Pure) and multiple event rollovers to determine which types of multiple event rollovers can be pooled with SV Pure to study rollover induced occupant injury. Four different types of multiple event rollovers were defined: single and multi-vehicle crashes for which the rollover is the most severe event (SV Prim and MV Prim) and single and multi-vehicle crashes for which the rollover is not the most severe event (SV Non-Prim and MV Non-Prim). Information from real world crashes was obtained from the National Automotive Sampling System - Crashworthiness Data System (NASS-CDS) for the period from 1995 through 2011. Belted, contained or partially ejected, adult occupants in vehicles that completed 1-16 lateral quarter turns were assigned to one of the five rollover categories. The results showed that the frequency of injury in non-primary rollovers (SV Non-Prim and MV Non-Prim) involving no more than one roof inversion is substantially greater than in SV Pure, but that this disparity diminishes for crashes involving multiple inversions. It can further be concluded that for a given number of roof inversions, the distribution of injuries and crash characteristics in SV Pure and SV Prim crashes are sufficiently similar for these categories to be considered collectively for purposes of understanding etiologies and developing strategies for prevention. PMID:26418467

  11. Motor Vehicle Crash-Related Subdural Hematoma from Real-World Head Impact Data

    OpenAIRE

    Urban, Jillian E.; Whitlow, Christopher T.; Edgerton, Colston A.; Powers, Alexander K.; Maldjian, Joseph A.; Stitzel, Joel D.

    2012-01-01

    Approximately 1,700,000 people sustain a traumatic brain injury (TBI) each year and motor vehicle crashes (MVCs) are a leading cause of hospitalization from TBI. Acute subdural hematoma (SDH) is a common intracranial injury that occurs in MVCs associated with high mortality and morbidity rates. In this study, SDH volume and midline shift have been analyzed in order to better understand occupant injury by correlating them to crash and occupant parameters. Fifty-seven head computed tomography (...

  12. Crashes on the way to and from coal mines in New South Wales

    Energy Technology Data Exchange (ETDEWEB)

    Mabbott, N. [ARRB Group Ltd. (Australia)

    2005-07-01

    This study investigated incidents and crashes on the way to and from coal mines in New South Wales. It collected injury data relevant to vehicular crushes of coal miners and incident data from responses to questionnaires. The crush data and incident data was explored for information relevant to prevalence, fatigue, mine type and time of day. Comparisons were made to the results of a similar study conducted in Queensland. It was found that a high number of incidents and crashes are occurring for coal miners on the way to and from coal mines in NSW. Some of the causes of these crashes have been related to factors such as fatigue, health, wildlife on the road and interactions with other drivers. Strategies have been developed to reduce the prevalence of these crashes. the counter measurers shown within this report have the capacity to reduce road trauma due to travel crashes of NSW coal miners. The dissemination of this report and discussion of the possible countermeasures are a useful stating point and will hopefully promulgate actions to reduce travel crash injuries. The information arising from the results of this projet has provided a strong platform on which to base strategies to reduce the prevalence of coal miners suffering road trauma. 16 refs., 2 figs., 4 tabs.

  13. Data development technical support document for the aircraft crash risk analysis methodology (ACRAM) standard

    International Nuclear Information System (INIS)

    The Aircraft Crash Risk Analysis Methodology (ACRAM) Panel has been formed by the US Department of Energy Office of Defense Programs (DOE/DP) for the purpose of developing a standard methodology for determining the risk from aircraft crashes onto DOE ground facilities. In order to accomplish this goal, the ACRAM panel has been divided into four teams, the data development team, the model evaluation team, the structural analysis team, and the consequence team. Each team, consisting of at least one member of the ACRAM plus additional DOE and DOE contractor personnel, specializes in the development of the methodology assigned to that team. This report documents the work performed by the data development team and provides the technical basis for the data used by the ACRAM Standard for determining the aircraft crash frequency. This report should be used to provide the generic data needed to calculate the aircraft crash frequency into the facility under consideration as part of the process for determining the aircraft crash risk to ground facilities as given by the DOE Standard Aircraft Crash Risk Assessment Methodology (ACRAM). Some broad guidance is presented on how to obtain the needed site-specific and facility specific data but this data is not provided by this document

  14. Analysis of driver injury severity in single-vehicle crashes on rural and urban roadways.

    Science.gov (United States)

    Wu, Qiong; Zhang, Guohui; Zhu, Xiaoyu; Liu, Xiaoyue Cathy; Tarefder, Rafiqul

    2016-09-01

    This study analyzes driver injury severities for single-vehicle crashes occurring in rural and urban areas using data collected in New Mexico from 2010 to 2011. Nested logit models and mixed logit models are developed in order to account for the correlation between severity categories (No injury, Possible injury, Visible injury, Incapacitating injury and fatality) and individual heterogeneity among drivers. Various factors, such as crash and environment characteristics, geometric features, and driver behavior are examined in this study. Nested logit model and mixed logit model reveal similar results in terms of identifying contributing factors for driver injury severities. In the analysis of urban crashes, only the nested logit model is presented since no random parameter is found in the mixed logit model. The results indicate that significant differences exist between factors contributing to driver injury severity in single-vehicle crashes in rural and urban areas. There are 5 variables found only significant in the rural model and six significant variables identified only in the urban crash model. These findings can help transportation agencies develop effective policies or appropriate strategies to reduce injury severity resulting from single-vehicle crashes. PMID:27240127

  15. The odds of wrong-way crashes and resulting fatalities: A comprehensive analysis.

    Science.gov (United States)

    Ponnaluri, Raj V

    2016-03-01

    The United States of America and other nations are grappling with the incidence of wrong-way driving (WWD). The issue is as important today (NTSB, 2012) as it was a half-century ago (Hulbert and Beers, 1966). In the absence of a comprehensive analysis, any effort to implement WWD countermeasures can be counterproductive. Hence, this effort began with the express intent to identify the factors that cause WWD crashes and fatalities. This work is sizeable in that it evaluated one million complete crash records from Florida. The methodology comprised (a) administering a survey on the perceptions about WWD; (b) developing binomial logistic models for computing the odds of WWD crashes, and of fatal crashes within the WWD space; (c) analyzing the contributing variables; and (d) comparing perceptions with crash analysis results. The study parameters included driver's age, gender, licensing state, physical defect, blood alcohol concentration, vehicle use, seatbelt compliance, day and time of crash, roadway lighting, facility type, weather conditions, road geometrics, and traffic volumes. Individual variable analysis of 23 parameters and the model development process included the determination of odds ratios and statistical tests for the predictive power and goodness-of-fit. The results of this work are generally consistent with expectation, yet surprising at times. This work concludes with decision-making inputs to the scientist, policy-maker and practitioner on the need for effectively engineering the roads, actively educating people about wrong-way driving, and strictly enforcing traffic laws, rules and regulations. PMID:26745273

  16. Observation of different phases during an ELM crash with the help of nitrogen seeding

    International Nuclear Information System (INIS)

    A new method was applied to indirectly obtain information about the features of the crash of the H-mode edge transport barrier in consequence of an edge localized mode (ELM). The method is based on a combination of fast measurements, without spatial resolution, and relatively slow measurements, with high spatial resolution. The comparison of two different ELM scenarios in the full metal tokamak ASDEX Upgrade—a standard scenario and one with additional nitrogen seeding—revealed a two-fold nature of the ELM crash. In the case with additional nitrogen only a part of the standard crash is observed. This suggests the standard ELM crash consists of two or more consecutive events instead of a single distinct one. Some of these events are observed to be suppressed with changes in plasma parameters. The effect of the impurity seeding on different plasma parameters is documented in detail and compared to measurements conducted in machines with a carbon wall. The radial extent of the phases observed during the ELM crash differs in the kinetic profiles, with one instability extending inside the pedestal top and the other being confined to the pedestal region. This picture can explain the differences in the loss of stored energy and the change in ELM frequency which are observed for the analysed pair of discharges. It also suggests that the ELM crash starts at the pedestal top and only then affects the steep gradient region. (paper)

  17. Driving risk assessment using near-crash database through data mining of tree-based model.

    Science.gov (United States)

    Wang, Jianqiang; Zheng, Yang; Li, Xiaofei; Yu, Chenfei; Kodaka, Kenji; Li, Keqiang

    2015-11-01

    This paper considers a comprehensive naturalistic driving experiment to collect driving data under potential threats on actual Chinese roads. Using acquired real-world naturalistic driving data, a near-crash database is built, which contains vehicle status, potential crash objects, driving environment and road types, weather condition, and driver information and actions. The aims of this study are summarized into two aspects: (1) to cluster different driving-risk levels involved in near-crashes, and (2) to unveil the factors that greatly influence the driving-risk level. A novel method to quantify the driving-risk level of a near-crash scenario is proposed by clustering the braking process characteristics, namely maximum deceleration, average deceleration, and percentage reduction in vehicle kinetic energy. A classification and regression tree (CART) is employed to unveil the relationship among driving risk, driver/vehicle characteristics, and road environment. The results indicate that the velocity when braking, triggering factors, potential object type, and potential crash type exerted the greatest influence on the driving-risk levels in near-crashes. PMID:26319604

  18. How the choice of safety performance function affects the identification of important crash prediction variables.

    Science.gov (United States)

    Wang, Ketong; Simandl, Jenna K; Porter, Michael D; Graettinger, Andrew J; Smith, Randy K

    2016-03-01

    Across the nation, researchers and transportation engineers are developing safety performance functions (SPFs) to predict crash rates and develop crash modification factors to improve traffic safety at roadway segments and intersections. Generalized linear models (GLMs), such as Poisson or negative binomial regression, are most commonly used to develop SPFs with annual average daily traffic as the primary roadway characteristic to predict crashes. However, while more complex to interpret, data mining models such as boosted regression trees have improved upon GLMs crash prediction performance due to their ability to handle more data characteristics, accommodate non-linearities, and include interaction effects between the characteristics. An intersection data inventory of 36 safety relevant parameters for three- and four-legged non-signalized intersections along state routes in Alabama was used to study the importance of intersection characteristics on crash rate and the interaction effects between key characteristics. Four different SPFs were investigated and compared: Poisson regression, negative binomial regression, regularized generalized linear model, and boosted regression trees. The models did not agree on which intersection characteristics were most related to the crash rate. The boosted regression tree model significantly outperformed the other models and identified several intersection characteristics as having strong interaction effects. PMID:26710265

  19. A spatial generalized ordered response model to examine highway crash injury severity.

    Science.gov (United States)

    Castro, Marisol; Paleti, Rajesh; Bhat, Chandra R

    2013-03-01

    This paper proposes a flexible econometric structure for injury severity analysis at the level of individual crashes that recognizes the ordinal nature of injury severity categories, allows unobserved heterogeneity in the effects of contributing factors, as well as accommodates spatial dependencies in the injury severity levels experienced in crashes that occur close to one another in space. The modeling framework is applied to analyze the injury severity sustained in crashes occurring on highway road segments in Austin, Texas. The sample is drawn from the Texas Department of Transportation (TxDOT) crash incident files from 2009 and includes a variety of crash characteristics, highway design attributes, driver and vehicle characteristics, and environmental factors. The results from our analysis underscore the value of our proposed model for data fit purposes as well as to accurately estimate variable effects. The most important determinants of injury severity on highways, according to our results, are (1) whether any vehicle occupant is ejected, (2) whether collision type is head-on, (3) whether any vehicle involved in the crash overturned, (4) whether any vehicle occupant is unrestrained by a seat-belt, and (5) whether a commercial truck is involved. PMID:23333845

  20. Conversion of the dominantly ideal perturbations into a tearing mode after a sawtooth crash

    Energy Technology Data Exchange (ETDEWEB)

    Igochine, V., E-mail: valentin.igochine@ipp.mpg.de; Gude, A.; Günter, S.; Lackner, K.; Yu, Q.; Barrera Orte, L.; McDermott, R. M. [Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Bogomolov, A.; Classen, I. [FOM-Institute DIFFER, Dutch Institute for Fundamental Energy Research, 3430 BE Nieuwegein (Netherlands); Luhmann, N. C. [University of California at Davis, Davis, California 95616 (United States)

    2014-11-15

    Forced magnetic reconnection is a topic of common interest in astrophysics, space science, and magnetic fusion research. The tearing mode formation process after sawtooth crashes implies the existence of this type of magnetic reconnection and is investigated in great detail in the ASDEX Upgrade tokamak. The sawtooth crash provides a fast relaxation of the core plasma temperature and can trigger a tearing mode at a neighbouring resonant surface. It is demonstrated for the first time that the sawtooth crash leads to a dominantly ideal kink mode formation at the resonant surface immediately after the sawtooth crash. Local measurements show that this kink mode transforms into a tearing mode on a much longer timescale (10{sup −3}s−10{sup −2}s) than the sawtooth crash itself (10{sup −4}s). The ideal kink mode formed after the sawtooth crash provides the driving force for magnetic reconnection and its amplitude is one of the critical parameters for the length of the transition phase from a ideal into an resistive mode. Nonlinear two fluid MHD simulations confirm these observations.

  1. Geography of irreducible plane sextics

    OpenAIRE

    Akyol, Ayşegül; Degtyarev, Alex

    2014-01-01

    We complete the equisingular deformation classification of irreducible singular plane sextic curves. As a by-product, we also compute the fundamental groups of the complement of all but a few maximizing sextics.

  2. Towards Improving Crash Data Management System in Gulf Countries

    Directory of Open Access Journals (Sweden)

    Dr. Jamal Almatawah

    2014-09-01

    Full Text Available Scientific and analytical approaches to accident data collection, storage and analysis are essential in dealing with road safety problems. Police accident records in the majority of countries form the main (and sometimes the only source of accident data. Access to the accident database is also important to identifying specific safety problems and evaluating the effectiveness of the countermeasure introduced. Accident data collection and analysis offered by technological innovation such as Electronic Data Entry (EDE, Electronic Data transfer (EDT, and Geographic Information system (GIS are implemented in developed countries. Developing countries, including the Gulf countries, should take advantage of the experience of developed countries on how the advance accident data management system works to identifying, more accurately, the main factors contributing to traffic accident. The main purpose of this research is to provide information on accident statistics process in Virginia state, starting from the time of accident occurring until it is stored in the database, with the aim of using it towards improving the process of collecting and maintaining accident data system in Gulf countries. The task is performed by reviewing the relevant international literature and interviewing police officers in charge and academic researchers in order to compare the accident data management system and also the quality of the data. Recommendations towards developing the crash data management system will be obtained based on the research results and international experience.

  3. Co-Movements Of U.S. And European Stock Markets Before And After The 2008 Gloal Stock Market Crash

    Directory of Open Access Journals (Sweden)

    Meric Ilhan

    2015-08-01

    Full Text Available Empirical studies show that correlation between national stock markets increased and the benefits of global portfolio diversification decreased significantly after the global stock market crash of 1987. The 1987 and 2008 crashes are the two most important global stock market crashes since the 1929 Great depression. Although the effects of the 1987 crash on the comovements of national stock markets have been investigated extensively, the effects of the 2008 crash have not been studied sufficiently. In this paper we study this issue with a research sample that includes the U.S stock market and twenty European stock markets. We find that correlation between the twenty-one stock markets increased and the benefits of portfolio diversification decreased significantly after the 2008 stock market crash.

  4. Exploring the impacts of factors contributing to tram-involved serious injury crashes on Melbourne tram routes.

    Science.gov (United States)

    Naznin, Farhana; Currie, Graham; Logan, David

    2016-09-01

    Previous research is limited regarding factors influencing tram-involved serious injury crashes. The aim of this study is to identify key vehicle, road, environment and driver related factors associated with tram-involved serious injury crashes. Using a binary logistic regression modelling approach, the following factors were identified to be significant in influencing tram-involved fatal crashes in Melbourne: tram floor height, tram age, season, traffic volume, tram lane priority and tram travel speed. Low floor trams, older trams, tram priority lanes and higher tram travelling speeds are more likely to increase tram-involved fatal crashes. Higher traffic volume decreases the likelihood of serious crashes. Fatal crashes are more likely to occur during spring and summer. Findings from this study may offer ideas for future research in the area of tram safety and help to develop countermeasures to prevent specific fatality types from occurring. PMID:27352035

  5. Road traffic crash circumstances and consequences among young unlicensed drivers: A Swedish cohort study on socioeconomic disparities

    OpenAIRE

    Laflamme Lucie; Hasselberg Marie; Hanna Christina L; Möller Jette

    2010-01-01

    Abstract Background Young car drivers run a higher risk of road traffic crash and injury not only because of their lack of experience but also because of their young age and their greater propensity for adopting unsafe driving practices. Also, low family socioeconomic position increases the risk of crash and of severe crash in particular. Whether this holds true for young unlicensed drivers as well is not known. Increasing attention is being drawn to the prevalence and practice of unlicensed ...

  6. Demographics, Velocity Distributions, and Impact Type as Predictors of AIS 4+ Head Injuries in Motor Vehicle Crashes

    OpenAIRE

    Yoganandan, Narayan; Fitzharris, Michael; Pintar, Frank A.; Stemper, Brian D.; Rinaldi, James; Maiman, Dennis J.; Fildes, Brian N.

    2011-01-01

    The objective of the study was to determine differences between the United States-based NASS and CIREN and Australia-based ANCIS databases in occupant-, crash-, and vehicle-related parameters for AIS 4+ head injuries in motor vehicle crashes. Logistic regression analysis was performed to examine roles of the change in velocity (DV), crash type (frontal, far-side, nearside, rear impact), seatbelt use, and occupant position, gender, age, stature, and body mass in cranial traumas. Belted and unb...

  7. Predicting Crashes Using Traffic Offences. A Meta-Analysis that Examines Potential Bias between Self-Report and Archival Data

    Science.gov (United States)

    af Wåhlberg, Anders; Freeman, James; Watson, Barry; Watson, Angela

    2016-01-01

    Background Traffic offences have been considered an important predictor of crash involvement, and have often been used as a proxy safety variable for crashes. However the association between crashes and offences has never been meta-analysed and the population effect size never established. Research is yet to determine the extent to which this relationship may be spuriously inflated through systematic measurement error, with obvious implications for researchers endeavouring to accurately identify salient factors predictive of crashes. Methodology and Principal Findings Studies yielding a correlation between crashes and traffic offences were collated and a meta-analysis of 144 effects drawn from 99 road safety studies conducted. Potential impact of factors such as age, time period, crash and offence rates, crash severity and data type, sourced from either self-report surveys or archival records, were considered and discussed. After weighting for sample size, an average correlation of r = .18 was observed over the mean time period of 3.2 years. Evidence emerged suggesting the strength of this correlation is decreasing over time. Stronger correlations between crashes and offences were generally found in studies involving younger drivers. Consistent with common method variance effects, a within country analysis found stronger effect sizes in self-reported data even controlling for crash mean. Significance The effectiveness of traffic offences as a proxy for crashes may be limited. Inclusion of elements such as independently validated crash and offence histories or accurate measures of exposure to the road would facilitate a better understanding of the factors that influence crash involvement. PMID:27128093

  8. Thoracic Injury Risk as a Function of Crash Severity – Car-to-car Side Impact Tests with WorldSID Compared to Real-life Crashes

    OpenAIRE

    Sunnevång, Cecilia; Rosén, Erik; Boström, Ola; Lechelt, Ulf

    2010-01-01

    Side airbags reduce the risk of fatal injury by approximately 30%. Due to limited real-life data the risk reducing effect for serious injury has not yet been established. Since side airbags are mainly designed and validated for crash severities used in available test procedures little is known regarding the protective effect when severity increases.

  9. Cyclists and drivers in road interactions: A comparison of perceived crash risk.

    Science.gov (United States)

    Chaurand, Nadine; Delhomme, Patricia

    2013-01-01

    Today's increase in the number of cyclists has triggered a change in the interactions to be handled by road users. However, few studies have investigated crash risk perceived by cyclists interacting with other users, and few have compared cyclists' and drivers' perceptions of crash risk in bike-car interactions, the most dangerous situation for cyclists. Our aims here are to study perceived crash risk (no matter the seriousness of the crash) in six common road situations during which cyclist crashes are frequent and also to study cyclists' and drivers' perceived risk in bike-car interactions, in comparison to other interaction types (cyclist vs. cyclist and driver vs. driver). We predicted that perceived risk of being involved in a crash during a particular interaction would be greater when in interaction with a car than with a bike, and that drivers would perceive more risk than cyclists would. We also predicted that perceived risk would decrease with drivers' and cyclists' experience of their transportation mode and their perceived control over the interaction situation. We ran an online survey on two samples, experienced cyclists (N=336) and non-cyclist car drivers (N=92). Participants evaluated their personal risk - as cyclists or as drivers - of being involved in a road crash if they were in an interaction with a bike or a car for each of six risky road situations. Experience was measured in terms of years of vehicle driving and driven km; perceived control was measured in terms of perceived skill and responsibility for the risky behavior. The results validated our hypotheses: perceived risk was higher for car drivers than for cyclists and for interacting with a car than with a bike. The implications of these results for interventions to improve road safety for both cyclists and car drivers are discussed. PMID:23021420

  10. Explosive plane-wave lens

    Science.gov (United States)

    Marsh, Stanley P.

    1988-01-01

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive.

  11. Plane waves as tractor beams

    Science.gov (United States)

    Forgács, Péter; Lukács, Árpád; Romańczukiewicz, Tomasz

    2013-12-01

    It is shown that in a large class of systems, plane waves act as tractor beams: i.e., an incident plane wave can exert a pulling force on the scatterer. The underlying physical mechanism for the pulling force is due to the sufficiently strong scattering of the incoming wave into another mode carrying more momentum, in which case excess momentum is created behind the scatterer. This tractor beam or negative radiation pressure (NRP) effect, is found to be generic in systems with multiple scattering channels. In a birefringent medium, electromagnetic plane waves incident on a thin plate exert NRP of the same order of magnitude as optical radiation pressure, while in artificial dielectrics (metamaterials), the magnitude of NRP can even be macroscopic. In two dimensions, we study various scattering situations on vortices, and NRP is shown to occur by the scattering of heavy baryons into light leptons off cosmic strings, and by neutron scattering off vortices in the XY model.

  12. Plane waves in noncommutative fluids

    International Nuclear Information System (INIS)

    We study the dynamics of the noncommutative fluid in the Snyder space perturbatively at the first order in powers of the noncommutative parameter. The linearized noncommutative fluid dynamics is described by a system of coupled linear partial differential equations in which the variables are the fluid density and the fluid potentials. We show that these equations admit a set of solutions that are monochromatic plane waves for the fluid density and two of the potentials and a linear function for the third potential. The energy–momentum tensor of the plane waves is calculated.

  13. Plane waves in noncommutative fluids

    Science.gov (United States)

    Abdalla, M. C. B.; Holender, L.; Santos, M. A.; Vancea, I. V.

    2013-08-01

    We study the dynamics of the noncommutative fluid in the Snyder space perturbatively at the first order in powers of the noncommutative parameter. The linearized noncommutative fluid dynamics is described by a system of coupled linear partial differential equations in which the variables are the fluid density and the fluid potentials. We show that these equations admit a set of solutions that are monochromatic plane waves for the fluid density and two of the potentials and a linear function for the third potential. The energy-momentum tensor of the plane waves is calculated.

  14. Plane waves in noncommutative fluids

    Energy Technology Data Exchange (ETDEWEB)

    Abdalla, M.C.B., E-mail: mabdalla@ift.unesp.br [Instituto de Física Teórica, UNESP, Universidade Estadual Paulista, Rua Dr. Bento Teobaldo Ferraz 271, Bloco 2, Barra-Funda, Caixa Postal 70532-2, 01156-970, São Paulo, SP (Brazil); Holender, L., E-mail: holender@ufrrj.br [Grupo de Física Teórica e Matemática Física, Departamento de Física, Universidade Federal Rural do Rio de Janeiro (UFRRJ), Cx. Postal 23851, BR 465 Km 7, 23890-000 Seropédica, RJ (Brazil); Santos, M.A., E-mail: masantos@cce.ufes.br [Departamento de Física e Química, Universidade Federal do Espírito Santo (UFES), Avenida Fernando Ferarri S/N, Goiabeiras, 29060-900 Vitória, ES (Brazil); Vancea, I.V., E-mail: ionvancea@ufrrj.br [Grupo de Física Teórica e Matemática Física, Departamento de Física, Universidade Federal Rural do Rio de Janeiro (UFRRJ), Cx. Postal 23851, BR 465 Km 7, 23890-000 Seropédica, RJ (Brazil)

    2013-08-01

    We study the dynamics of the noncommutative fluid in the Snyder space perturbatively at the first order in powers of the noncommutative parameter. The linearized noncommutative fluid dynamics is described by a system of coupled linear partial differential equations in which the variables are the fluid density and the fluid potentials. We show that these equations admit a set of solutions that are monochromatic plane waves for the fluid density and two of the potentials and a linear function for the third potential. The energy–momentum tensor of the plane waves is calculated.

  15. Side Impact Regulatory Trends, Crash Environment and Injury Risk in the USA.

    Science.gov (United States)

    Prasad, Priya; Dalmotas, Dainius; Chouinard, Aline

    2015-11-01

    Light duty vehicles in the US are designed to meet and exceed regulatory standards, self-imposed industry agreements and safety rating tests conducted by NHTSA and IIHS. The evolution of side impact regulation in the US from 1973 to 2015 is discussed in the paper along with two key industry agreements in 2003 affecting design of restraint systems and structures for side impact protection. A combination of all the above influences shows that vehicles in the US are being designed to more demanding and comprehensive requirements than in any other region of the world. The crash environment in the US related to side impacts was defined based on data in the nationally representative crash database NASS. Crash environment factors, including the distribution of cars, light trucks and vans (LTV's), and medium-to-heavy vehicles (MHV's) in the fleet, and the frequency of their interactions with one another in side impacts, were considered. Other factors like, crash severity in terms of closing velocity between two vehicles involved in crash, gender and age of involved drivers in two-vehicle and single vehicle crashes, were also examined. Injury risks in side impacts to drivers and passengers were determined in various circumstances such as near-side, far-side, and single vehicle crashes as a function of crash severity, in terms of estimated closing speed or lateral delta-V. Also injury risks in different pairs of striking and struck cars and LTV's, were estimated. A logistic regression model for studying injury risks in two vehicle crashes was developed. The risk factors included in the model include case and striking vehicles, consisting of cars, SUV's, vans, and pickup trucks, delta-V, damage extent, occupant proximity to the impact side, age and gender of the occupant, and belt use. Results show that car occupants make up the vast majority of serious-to-fatally injured occupants. Injury rates of car occupants in two-vehicle collision are highest when the car is struck by a

  16. Effects from airplane crashes and gas explosions to Leningrad nuclear plant

    Energy Technology Data Exchange (ETDEWEB)

    Junttila, K.; Varpasuo, P. [IVO Power Engineering Oy, Vantaa (Finland)

    1998-12-31

    In this study the effects of aircraft crash and gas explosion to Leningrad Nuclear Power Plant has been researched. One of the two reactor buildings is modeled with finite element method using the pre-processor program MSC/PATRAN and analyzed with MSC/NASTRAN analysis program. In MSC/PATRAN or FEMAP, which is a pre-processor program of MSC/NASTRAN for Windows, the reactor building of the plant has been modeled with shell and beam elements and the load sets describing the aircraft crash and gas explosion have been developed. The crash loads are from Cessna 210 civil airplane crash with impact velocity 360 km/h and maximum impact force of 7 MN and Phantom RF-43 military airplane crash with impact velocity 215 m/s and with maximum impact force of 110 MN. The gas explosion pressure wave simulates the deflagration wave with maximum pressure of 0,045 MPa. Seven Cessna 210 airplane crash locations, two Phantom RF-43 airplane crash locations and one gas explosion load case is modeled. Airplane crash loads were from different directions and to different points of impact in the reactor building. The gas explosion load was assumed to affect the reactor building from one side parallel to one of the global coordinate axes of the model. With MSC/NASTRAN reactions from loads are analyzed. All loads were timedependent; their magnitude varied with time and consequently the analysis was carried out with the aid of transient response analysis. Time step in Cessna 210 analysis was 0,003 s and in Phantom RF-43 and gas explosion analyses 0,01 s. The greatest displacement from Cessna 210 loads was 12 mm and from Phantom RF-43 load 344 mm. The last value shows that construction would fail with that load. The greatest displacement from gas explosion load was 68 mm. Stresses are not so interesting in this preliminary analysis of the effects, but they are shown in pictures embedded in the report text. Displacements were greatest in upper part of the reactor building, where no intersections

  17. Patologia da comunicação: Crash sem pentecostes

    Directory of Open Access Journals (Sweden)

    Olgária Chain Féres Matos

    2008-11-01

    Full Text Available O objetivo do ensaio é mostrar a metrópole como o sujeito histórico da contemporaneidade, por meio da análise do filme Crash. Ela é o microcosmo em que se comunicam indivíduos pela mediação do automóvel. Nela inscrevem-se as relações sociais e seus conflitos: xenofobia, racismo, particularismos legais e desregulamentações políticas. Mundo menos dominado por pessoas e mais pelo acaso, ele resulta da determinação de todas as esferas da vida pelo fator econômico e pelas derivas do mercado mundial, forma moderna do destino. Palavras-chave: crash; estado de direito; estado de exceção; fundamentalismos Abstract: The Pathology of Communication: Crash without Pentecost — The purpose of this essay is to portray the metropolis as the historical subject of contemporaneousness, based on an analysis of the movie Crash, which illustrates the microcosm in which individual communications are mediated by the automobile and which is marked by social relations and their conflicts: xenophobia, racism, legal particularities and political deregulation. A world ruled by fortuitousness rather than by human will, it is the product of the determination of all spheres of life by economic factors and by global market trends, seen as the modern depiction of fate. Keywords: Crash; rule of law; rule of exception; fundamentalism

  18. A mixed logit analysis of two-vehicle crash severities involving a motorcycle.

    Science.gov (United States)

    Shaheed, Mohammad Saad B; Gkritza, Konstantina; Zhang, Wei; Hans, Zachary

    2013-12-01

    Using motorcycle crash data for Iowa from 2001 to 2008, this paper estimates a mixed logit model to investigate the factors that affect crash severity outcomes in a collision between a motorcycle and another vehicle. These include crash-specific factors (such as manner of collision, motorcycle rider and non-motorcycle driver and vehicle actions), roadway and environmental conditions, location and time, motorcycle rider and non-motorcycle driver and vehicle attributes. The methodological approach allows the parameters to vary across observations as opposed to a single parameter representing all observations. Our results showed non-uniform effects of rear-end collisions on minor injury crashes, as well as of the roadway speed limit greater or equal to 55mph, the type of area (urban), the riding season (summer) and motorcyclist's gender on low severity crashes. We also found significant effects of the roadway surface condition, clear vision (not obscured by moving vehicles, trees, buildings, or other), light conditions, speed limit, and helmet use on severe injury outcomes. PMID:23830505

  19. Analyzing and modeling risk exposure of pedestrian children to involvement in car crashes.

    Science.gov (United States)

    Elias, Wafa; Shiftan, Yoram

    2014-01-01

    This paper analyzes the various variables affecting pedestrian children road crashes, placing emphasis on the effect of daily activity patterns and the built environment, including the children's residential neighborhoods and the land use of the places where they conduct their activities. Two complementary data sources from the case study of an Arab town in northern Israel were used to provide a holistic picture of child-pedestrian road crashes: police files providing detailed analyzes of the reason for each crash, its location, and the characteristics of the driver involved; and a survey of 199 households with both involved and not involved children in road crashes, including a one-day travel diary. The study found that a combination of three groups of variables affects child-pedestrian road crashes: socio-economic status, travel patterns, and land use. Most vulnerable are boys from a low socio-economic group who live in areas of high density and mixed land use near a major road and who tend to walk to and from school and additional activities after school. PMID:23915471

  20. Experimental Photogrammetric Techniques Used on Five Full-Scale Aircraft Crash Tests

    Science.gov (United States)

    Littell, Justin D.

    2016-01-01

    Between 2013 and 2015, full-scale crash tests were conducted on five aircraft at the Landing and Impact Research Facility (LandIR) at NASA Langley Research Center (LaRC). Two tests were conducted on CH-46E airframes as part of the Transport Rotorcraft Airframe Crash Testbed (TRACT) project, and three tests were conduced on Cessna 172 aircraft as part of the Emergency Locator Transmitter Survivability and Reliability (ELTSAR) project. Each test served to evaluate a variety of crashworthy systems including: seats, occupants, restraints, composite energy absorbing structures, and Emergency Locator Transmitters. As part of each test, the aircraft were outfitted with a variety of internal and external cameras that were focused on unique aspects of the crash event. A subset of three camera was solely used in the acquisition of photogrammetric test data. Examples of this data range from simple two-dimensional marker tracking for the determination of aircraft impact conditions to entire full-scale airframe deformation to markerless tracking of Anthropomorphic Test Devices (ATDs, a.k.a. crash test dummies) during the crash event. This report describes and discusses the techniques used and implications resulting from the photogrammetric data acquired from each of the five tests.

  1. Design of lightweight magnesium car body structure under crash and vibration constraints

    Directory of Open Access Journals (Sweden)

    Morteza Kiani

    2014-06-01

    Full Text Available Car body design in view of structural performance and lightweighting is a challenging task due to all the performance targets that must be satisfied such as vehicle safety and ride quality. In this paper, material replacement along with multidisciplinary design optimization strategy is proposed to develop a lightweight car body structure that satisfies the crash and vibration criteria while minimizing weight. Through finite element simulations, full frontal, offset frontal, and side crashes of a full car model are evaluated for peak acceleration, intrusion distance, and the internal energy absorbed by the structural parts. In addition, the first three fundamental natural frequencies are combined with the crash metrics to form the design constraints. The wall thicknesses of twenty-two parts are considered as the design variables. Latin Hypercube Sampling is used to sample the design space, while Radial Basis Function methodology is used to develop surrogate models for the selected crash responses at multiple sites as well as the first three fundamental natural frequencies. A nonlinear surrogate-based optimization problem is formulated for mass minimization under crash and vibration constraints. Using Sequential Quadratic Programming, the design optimization problem is solved with the results verified by finite element simulations. The performance of the optimum design with magnesium parts shows significant weight reduction and better performance compared to the baseline design.

  2. Application of the Hyper-Poisson Generalized Linear Model for Analyzing Motor Vehicle Crashes.

    Science.gov (United States)

    Khazraee, S Hadi; Sáez-Castillo, Antonio Jose; Geedipally, Srinivas Reddy; Lord, Dominique

    2015-05-01

    The hyper-Poisson distribution can handle both over- and underdispersion, and its generalized linear model formulation allows the dispersion of the distribution to be observation-specific and dependent on model covariates. This study's objective is to examine the potential applicability of a newly proposed generalized linear model framework for the hyper-Poisson distribution in analyzing motor vehicle crash count data. The hyper-Poisson generalized linear model was first fitted to intersection crash data from Toronto, characterized by overdispersion, and then to crash data from railway-highway crossings in Korea, characterized by underdispersion. The results of this study are promising. When fitted to the Toronto data set, the goodness-of-fit measures indicated that the hyper-Poisson model with a variable dispersion parameter provided a statistical fit as good as the traditional negative binomial model. The hyper-Poisson model was also successful in handling the underdispersed data from Korea; the model performed as well as the gamma probability model and the Conway-Maxwell-Poisson model previously developed for the same data set. The advantages of the hyper-Poisson model studied in this article are noteworthy. Unlike the negative binomial model, which has difficulties in handling underdispersed data, the hyper-Poisson model can handle both over- and underdispersed crash data. Although not a major issue for the Conway-Maxwell-Poisson model, the effect of each variable on the expected mean of crashes is easily interpretable in the case of this new model. PMID:25385093

  3. Macroscopic modeling of pedestrian and bicycle crashes: A cross-comparison of estimation methods.

    Science.gov (United States)

    Amoh-Gyimah, Richard; Saberi, Meead; Sarvi, Majid

    2016-08-01

    The paper presents a cross-comparison of different estimation methods to model pedestrian and bicycle crashes. The study contributes to macro level safety studies by providing further methodological and empirical evidence on the various factors that influence the frequency of pedestrian and bicycle crashes at the planning level. Random parameter negative binomial (RPNB) models are estimated to explore the effects of various planning factors associated with total, serious injury and minor injury crashes while accounting for unobserved heterogeneity. Results of the RPNB models were compared with the results of a non-spatial negative binomial (NB) model and a Poisson-Gamma-CAR model. Key findings are, (1) the RPNB model performed best with the lowest mean absolute deviation, mean squared predicted error and Akaiki information criterion measures and (2) signs of estimated parameters are consistent if these variables are significant in models with the same response variables. We found that vehicle kilometers traveled (VKT), population, percentage of commuters cycling or walking to work, and percentage of households without motor vehicles have a significant and positive correlation with the number of pedestrian and bicycle crashes. Mixed land use is also found to have a positive association with the number of pedestrian and bicycle crashes. Results have planning and policy implications aimed at encouraging the use of sustainable modes of transportation while ensuring the safety of pedestrians and cyclist. PMID:27209153

  4. Origin of crashes in three US stock markets: shocks and bubbles

    Science.gov (United States)

    Johansen, Anders

    2004-07-01

    This paper presents an exclusive classification of the largest crashes in Dow Jones industrial average, SP500 and NASDAQ in the past century. Crashes are objectively defined as the top-rank filtered drawdowns (loss from the last local maximum to the next local minimum disregarding noise fluctuations), where the size of the filter is determined by the historical volatility of the index. It is shown that all crashes can be linked to either an external shock, e.g., outbreak of war, or a log-periodic power law (LPPL) bubble with an empirically well-defined complex value of the exponent. Conversely, with one sole exception all previously identified LPPL bubbles are followed by a top-rank drawdown. As a consequence, the analysis presented suggest a one-to-one correspondence between market crashes defined as top-rank filtered drawdowns on one hand and surprising news and LPPL bubbles on the other. We attribute this correspondence to the efficient market hypothesis effective on two quite different time scales depending on whether the market instability the crash represent is internally or externally generated.

  5. Serious head and neck injury as a predictor of occupant position in fatal rollover crashes.

    Science.gov (United States)

    Freeman, M D; Dobbertin, K; Kohles, S S; Uhrenholt, L; Eriksson, A

    2012-10-10

    Serious head and neck injuries are a common finding in fatalities associated with rollover crashes. In some fatal rollover crashes, particularly when ejection occurs, the determination of which occupant was driving at the time of the crash may be uncertain. In the present investigation, we describe the analysis of rollover crash data from the National Automotive Sampling System-Crashworthiness Data System for the years 1997 through 2007 in which we examined the relationship between a serious head and neck injury in an occupant and a specified degree of roof deformation at the occupant's seating position. We found 960 occupants who qualified for the analysis, with 142 deaths among the subjects. Using a ranked composite head and neck injury score (the HNISS) we found a strong relationship between HNISS and the degree of roof crush. As a result of the analysis, we arrived at a predictive model, in which each additional unit increase in HNISS equated to an increased odds of roof crush as follows: for ≥8 cm of roof crush compared with occupant position in a rollover crash-related fatality. PMID:22742739

  6. Comparison of risk factors for cervical spine, head, serious, and fatal injury in rollover crashes.

    Science.gov (United States)

    Funk, James R; Cormier, Joseph M; Manoogian, Sarah J

    2012-03-01

    Previous epidemiological studies of rollover crashes have focused primarily on serious and fatal injuries in general, while rollover crash testing has focused almost exclusively on cervical spine injury. The purpose of this study was to examine and compare the risk factors for cervical spine, head, serious, and fatal injury in real world rollover crashes. Rollover crashes from 1995-2008 in the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) were investigated. A large data set of 6015 raw cases (2.5 million weighted) was generated. Nonparametric univariate analyses, univariate logistic regression, and multivariate logistic regression were conducted. Complete or partial ejection, a lack of seatbelt use, a greater number of roof inversions, and older occupant age significantly increased the risk of all types of injuries studied (phead, and cervical spine injury (pinjury in general. Higher BMI was associated with an increased risk of fatal, serious, and cervical spine injury (phead injury. Greater roof crush was associated with a higher rate of fatal and cervical spine injury (poccupant height, and occupant gender had inconsistent and generally non-significant effects on injury. This study demonstrates both common and unique risk factors for different types of injuries in rollover crashes. PMID:22269486

  7. Robust human body model injury prediction in simulated side impact crashes.

    Science.gov (United States)

    Golman, Adam J; Danelson, Kerry A; Stitzel, Joel D

    2016-01-01

    This study developed a parametric methodology to robustly predict occupant injuries sustained in real-world crashes using a finite element (FE) human body model (HBM). One hundred and twenty near-side impact motor vehicle crashes were simulated over a range of parameters using a Toyota RAV4 (bullet vehicle), Ford Taurus (struck vehicle) FE models and a validated human body model (HBM) Total HUman Model for Safety (THUMS). Three bullet vehicle crash parameters (speed, location and angle) and two occupant parameters (seat position and age) were varied using a Latin hypercube design of Experiments. Four injury metrics (head injury criterion, half deflection, thoracic trauma index and pelvic force) were used to calculate injury risk. Rib fracture prediction and lung strain metrics were also analysed. As hypothesized, bullet speed had the greatest effect on each injury measure. Injury risk was reduced when bullet location was further from the B-pillar or when the bullet angle was more oblique. Age had strong correlation to rib fractures frequency and lung strain severity. The injuries from a real-world crash were predicted using two different methods by (1) subsampling the injury predictors from the 12 best crush profile matching simulations and (2) using regression models. Both injury prediction methods successfully predicted the case occupant's low risk for pelvic injury, high risk for thoracic injury, rib fractures and high lung strains with tight confidence intervals. This parametric methodology was successfully used to explore crash parameter interactions and to robustly predict real-world injuries. PMID:26158552

  8. Can a video-based hazard perception test used for driver licensing predict crash involvement?

    Science.gov (United States)

    Horswill, Mark S; Hill, Andrew; Wetton, Mark

    2015-09-01

    In 2008, the state of Queensland in Australia introduced a video-based hazard perception test as part of the licensing process for new drivers. A key validity check for such a test is whether scores are associated with crash involvement. We present data demonstrating that drivers who failed the hazard perception test (based on a ROC curve-derived pass mark) were 25% [95% confidence interval (CI) 6%, 48%] more likely to be involved in an active crash (defined as a crash occurring while the driver's vehicle was moving but they were not engaged in parking or reversing) during a one year period following the test (controlling for driving exposure, age, and sex). Failing drivers were also 17% (95% CI 6%, 29%) more likely to have been involved in active crashes prior to the test, in the period since obtaining their provisional license. These data support the proposal that the hazard perception test is a valid measure of crash-related driving performance. PMID:26093097

  9. Structural integrity analysis of an Ignalina nuclear power plant building subjected to an airplane crash

    International Nuclear Information System (INIS)

    Recent terrorist attacks using commandeered commercial airliners on civil structures have raised the issue of the ability of nuclear power plants to survive the consequences of an airliner crash. The structural integrity analysis due to the effects of an aircraft crash on an Ignalina nuclear power plant (INPP) accident localization system (ALS) building is the subject of this paper. A combination of the finite element method and empirical relationships were used for the analysis. A global structural integrity analysis was performed for a portion of the ALS building using the dynamic loading from an aircraft crash impact model. The local effects caused by impact of the aircraft's engine on the building wall were evaluated independently by using an empirical formula. The results from the crash analysis of a twin engine commercial aircraft show that the impacted reinforced concrete wall of the ALS building will not have through-the-wall concrete failure, and the reinforcement will not fail. Strain-rate effects were found to delay the onset of cracking. Therefore, the structural integrity of the impacted wall of the INPP ALS building will be maintained during the crash event studied

  10. Force Lines in Plane Stress

    DEFF Research Database (Denmark)

    Rathkjen, Arne

    A state of plane stress is illustrated by means of two families of curves, each family representing constant values of a derivative of Airy's stress function. The two families of curves form a map giving in the first place an overall picture of regions of high and low stress, and in the second...

  11. Plane and parabolic solar panels

    OpenAIRE

    Sales, J. H. O.; Suzuki, A.T.

    2009-01-01

    We present a plane and parabolic collector that absorbs radiant energy and transforms it in heat. Therefore we have a panel to heat water. We study how to increment this capture of solar beams onto the panel in order to increase its efficiency in heating water.

  12. Identification of Energy Distribution for Crash Deformational Processes of Road Vehicles

    Directory of Open Access Journals (Sweden)

    István Harmati

    2007-08-01

    Full Text Available Car body deformation modelling plays a very important role in crash accidentanalyses, as well as in safe car body design. The determination of the energy absorbed bythe deformation and the corresponding Energy Equivalent Speed can be of key importance;however their precise determination is a very difficult task. Although, using the results ofcrash tests, intelligent and soft methods offer an automatic way to model the crash processitself, as well as to determine the absorbed energy, the before-crash speed of the car, etc. Inthis paper a model is introduced which is able to describe the changing of the energydistribution during the whole deformational process and to analyze the strength of thedifferent parts without any human intervention thus significantly can contribute to theimprovement of the modelling, (automatic design, and safety of car bodies.

  13. Influence of equilibrium shear flow on peeling-ballooning instability and edge localized mode crash

    International Nuclear Information System (INIS)

    The E × B shear flow plays a dual role on peeling-ballooning modes and their subsequently triggered edge localized mode (ELM) crashes. On one hand, the flow shear can stabilize high-n modes and twist the mode in the poloidal direction, constraining the mode's radial extent and reducing the size of the corresponding ELM. On the other hand, the shear flow also introduces the Kelvin-Helmholtz drive, which can destabilize peeling-ballooning modes. The overall effect of equilibrium shear flow on peeling-ballooning modes and ELM crashes depends on the competition between these two effects. When the flow shear is either small or very large, it can reduce ELM size. However, for moderate values of flow shear, the destabilizing effect from the Kelvin-Helmholtz term is dominant and leads to larger ELM crashes.

  14. Effects of sawtooth crashes on beam ions and fusion product tritons in JET

    Energy Technology Data Exchange (ETDEWEB)

    Marcus, F.B.; Hone, M.A.; Jarvis, O.N.; Loughlin, M.J.; Sadler, G. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Adams, J.M.; Bond, D.S.; Watkins, N. [UKAEA Harwell Lab. (United Kingdom). Energy Technology Div.; Howarth, P.J.A. [Birmingham Univ. (United Kingdom)

    1994-07-01

    The effect of a sawtooth crash on the radial distribution of the slowing down fusion product tritons and on beams ions, is examined with measurements of the 2.5 MeV and 14 MeV neutron emission line-integrals before and after sawtooth crashes. In deuterium discharges, the 14 MeV neutron production was wholly attributable to burnup of the 1 MeV fusion product tritons from d-d fusion. The local emissivity of 14 MeV neutrons, and hence of the profile of thermalizing tritons, is shown to be only weakly affected by crashes in the discharges studied. This is in contradiction with the apparent behaviour of injected beam ions as deduced from a study of the considerable changes in local emissivity of the 2.5 MeV neutrons. Nevertheless, the behaviour of the fusion product tritons is consistent with the scaling of the beam injected deuterium. 1 ref., 6 figs.

  15. Regression Model for Light Weight and Crashworthiness Enhancement Design of Automotive Parts in Frontal CAR Crash

    Science.gov (United States)

    Bae, Gihyun; Huh, Hoon; Park, Sungho

    This paper deals with a regression model for light weight and crashworthiness enhancement design of automotive parts in frontal car crash. The ULSAB-AVC model is employed for the crash analysis and effective parts are selected based on the amount of energy absorption during the crash behavior. Finite element analyses are carried out for designated design cases in order to investigate the crashworthiness and weight according to the material and thickness of main energy absorption parts. Based on simulations results, a regression analysis is performed to construct a regression model utilized for light weight and crashworthiness enhancement design of automotive parts. An example for weight reduction of main energy absorption parts demonstrates the validity of a regression model constructed.

  16. Optimization of Car Body under Constraints of Noise, Vibration, and Harshness (NVH), and Crash

    Science.gov (United States)

    Kodiyalam, Srinivas; Yang, Ren-Jye; Sobieszczanski-Sobieski, Jaroslaw (Editor)

    2000-01-01

    To be competitive on the today's market, cars have to be as light as possible while meeting the Noise, Vibration, and Harshness (NVH) requirements and conforming to Government-man dated crash survival regulations. The latter are difficult to meet because they involve very compute-intensive, nonlinear analysis, e.g., the code RADIOSS capable of simulation of the dynamics, and the geometrical and material nonlinearities of a thin-walled car structure in crash, would require over 12 days of elapsed time for a single design of a 390K elastic degrees of freedom model, if executed on a single processor of the state-of-the-art SGI Origin2000 computer. Of course, in optimization that crash analysis would have to be invoked many times. Needless to say, that has rendered such optimization intractable until now. The car finite element model is shown. The advent of computers that comprise large numbers of concurrently operating processors has created a new environment wherein the above optimization, and other engineering problems heretofore regarded as intractable may be solved. The procedure, shown, is a piecewise approximation based method and involves using a sensitivity based Taylor series approximation model for NVH and a polynomial response surface model for Crash. In that method the NVH constraints are evaluated using a finite element code (MSC/NASTRAN) that yields the constraint values and their derivatives with respect to design variables. The crash constraints are evaluated using the explicit code RADIOSS on the Origin 2000 operating on 256 processors simultaneously to generate data for a polynomial response surface in the design variable domain. The NVH constraints and their derivatives combined with the response surface for the crash constraints form an approximation to the system analysis (surrogate analysis) that enables a cycle of multidisciplinary optimization within move limits. In the inner loop, the NVH sensitivities are recomputed to update the NVH

  17. Recession depression: mental health effects of the 2008 stock market crash.

    Science.gov (United States)

    McInerney, Melissa; Mellor, Jennifer M; Nicholas, Lauren Hersch

    2013-12-01

    Do sudden, large wealth losses affect mental health? We use exogenous variation in the interview dates of the 2008 Health and Retirement Study to assess the impact of large wealth losses on mental health among older U.S. adults. We compare cross-wave changes in wealth and mental health for respondents interviewed before and after the October 2008 stock market crash. We find that the crash reduced wealth and increased feelings of depression and use of antidepressant drugs, and that these effects were largest among respondents with high levels of stock holdings prior to the crash. These results suggest that sudden wealth losses cause immediate declines in subjective measures of mental health. However, we find no evidence that wealth losses lead to increases in clinically-validated measures of depressive symptoms or indicators of depression. PMID:24113241

  18. Multifractal analysis and instability index of prior-to-crash market situations

    CERN Document Server

    Piacquadio, M

    2009-01-01

    We take prior-to-crash market prices (NASDAQ, Dow Jones Industrial Average) as a signal, a function of time, we project these discrete values onto a vertical axis, thus obtaining a Cantordust. We study said cantordust with the tools of multifractal analysis, obtaining spectra by definition and by lagrangian coordinates. These spectra have properties that typify the prior-to-crash market situation. Any of these spectra entail elaborate processing of the raw signal data. With the unprocessed raw data we obtain an instability index, also with properties that typify the prior-to-crisis market situation. Both spectra and the instability index agree in characterizing such crashes, and in giving an early warning of them.

  19. Collective Behavior of Stock Prices as a Precursor to Market Crash

    Science.gov (United States)

    Maskawa, J.

    We study precursors to the global market crash that occurred onall main stock exchanges throughout the world in October 2008 about three weeks after the bankruptcy of Lehman Brothers Holdings Inc. on 15 September. We examine the collective behavior of stock returns and analyze the market mode, which is a market-wide collective mode, with constituent issues of the FTSE 100 index listed on the London Stock Exchange. Before the market crash, a sharp rise in a measure of the collective behavior was observed. It was shown to be associated with news including the words ``financial crisis". They did not impact stock prices severely alone, but they exacerbated the pessimistic mood that prevailed among stock market participants. Such news increased after the Lehman shock preceding the market crash. The variance increased along with the cumulative amount of news according to a power law.

  20. Linear Instability of the Plane Couette and Plane Poiseuille Flows

    CERN Document Server

    Chefranov, Sergey G

    2015-01-01

    We show possibility of the Plane Couette (PC) flow instability for Reynolds number Re>Reth=140. This new result of the linear hydrodynamic stability theory is obtained on the base of refusal from the traditionally used assumption on longitudinal periodicity of the disturbances along the direction of the fluid flow. We found that earlier existing understanding on the linear stability of this flow for any arbitrary large Reynolds number is directly related with an assumption on the separation of the variables of the spatial variability for the disturbance field and their periodicity in linear theory of stability. By the refusal from the pointed assumptions also for the Plane Poiseuille (PP) flow, we get a new threshold Reynolds value Reth=1040 that with 4% accuracy agrees with the experiment contrary to more than 500% discrepancy for the earlier known estimate Reth=5772 obtained in the frame of the linear theory but when using the "normal" disturbance form (S. A. Orszag, 1971).

  1. Gravitational Couplings for y-Gop-Planes

    CERN Document Server

    Ospina-Giraldo, J F

    2000-01-01

    The Wess-Zumino action for y deformed and generalized orientifold planes (yGOp-planes) is presented and one power expantion is realized from which processes that involves yGOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard yGOp-planes are showed.

  2. Gravitational Couplings for Generalized Orientifold Planes

    CERN Document Server

    Ospina-Giraldo, J F

    2000-01-01

    The Wess-Zumino action for generalized orientifold planes (GOp-planes) is presented and a series power expantion is realized from which processes that involves GOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard GOp-planes are showed.

  3. Optimization of starshades: focal plane versus pupil plane

    Science.gov (United States)

    Flamary, R.; Aime, C.

    2014-09-01

    We search for the best possible transmission for an external occulter coronagraph that is dedicated to the direct observation of terrestrial exoplanets. We show that better observation conditions are obtained when the flux in the focal plane is minimized in the zone in which the exoplanet is observed, instead of for the total flux received by the telescope. We describe the transmission of the occulter as a sum of basis functions. For each element of the basis, we numerically computed the Fresnel diffraction at the aperture of the telescope and the complex amplitude at its focus. The basis functions are circular disks that are linearly apodized over a few centimeters (truncated cones). We complemented the numerical calculation of the Fresnel diffraction for these functions by a comparison with pure circular disks (cylinder) for which an analytical expression, based on a decomposition in Lommel series, is available. The technique of deriving the optimal transmission for a given spectral bandwidth is a classical regularized quadratic minimization of intensities, but linear optimizations can be used as well. Minimizing the integrated intensity on the aperture of the telescope or for selected regions of the focal plane leads to slightly different transmissions for the occulter. For the focal plane optimization, the resulting residual intensity is concentrated behind the geometrical image of the occulter, in a blind region for the observation of an exoplanet, and the level of background residual starlight becomes very low outside this image. Finally, we provide a tolerance analysis for the alignment of the occulter to the telescope, which also favors the focal plane optimization. This means that telescope offsets of a few decimeters do not strongly reduce the efficiency of the occulter.

  4. Effect of forming rate on the impact tensile properties of the steels under crash test

    Directory of Open Access Journals (Sweden)

    M. Grumbach

    2007-01-01

    Full Text Available Purpose: The main objective of this study is to examine the mechanical and metallurgical behaviour of thetailored blanks and base metals for thin sheet steels used in the car industry by using a new type of crash test/impact (ITT. It exposes the effect of forming rate on the toughness of thin welded joints (tailored blanks forInterstitial Free (IFS steels used in the automotive industry.Design/methodology/approach: A special crash test device is used in different temperature and the simulatedcrash tests are performed at a constant speed of 5.52 m/s (strain rate about 250 s−1.Findings: The specimen is submitted to impact tensile test at different temperatures. According to testingtemperature, fracture mode varies: At low temperatures, brittle fracture occurs: Due to stress concentration,fracture always occurs in the notched section. At high temperatures, the specimen fails by ductile fracture.Toughness of the steel sheets (base metals, BM or tailored blanks, TBs after forming at certain levels is wellcompared at different materials and test conditions.Practical implications: This study gives very useful data for the crash test. This is a new conception ofspecimen and of the impact/crash machine. It is easily used in automotive industry for practical and economicreason to give rapid answers to designer and also steel makers for ranking the materials.Originality/value: This research used a new developed test called simplified crash test for evaluating theeffect of forming rate on the toughness of thin welded joints (tailored blanks / mechanical assemblies in highformability steel sheets for stamping submitted to dynamic loads such as experienced in real crash tests.

  5. Are drivers aware of sleepiness and increasing crash risk while driving?

    Science.gov (United States)

    Williamson, Ann; Friswell, Rena; Olivier, Jake; Grzebieta, Raphael

    2014-09-01

    Drivers are advised to take breaks when they feel too tired to drive, but there is question over whether they are able to detect increasing fatigue and sleepiness sufficiently to decide when to take a break. The aim of this study was to investigate the extent to which drivers have access to cognitive information about their current state of sleepiness, likelihood of falling asleep, and the implications for driving performance and the likelihood of crashing. Ninety drivers were recruited to do a 2h drive in a driving simulator. They were divided into three groups: one made ratings of their sleepiness, likelihood of falling asleep and likelihood of crashing over the next few minutes at prompts occurring at 200s intervals throughout the drive, the second rated sleepiness and likelihood of falling asleep at prompts but pressed a button on the steering wheel at any time if they felt they were near to crashing and the third made no ratings and only used a button-press if they felt a crash was likely. Fatigue and sleepiness was encouraged by monotonous driving conditions, an imposed shorter than usual sleep on the night before and by afternoon testing. Drivers who reported that they were possibly, likely or very likely to fall asleep in the next few minutes, were more than four times more likely to crash subsequently. Those who rated themselves as sleepy or likely to fall asleep had a more than 9-fold increase in the hazards of a centerline crossing compared to those who rated themselves as alert. The research shows clearly that drivers can detect changes in their levels of sleepiness sufficiently to make a safe decision to stop driving due to sleepiness. Therefore, road safety policy needs to move from reminding drivers of the signs of sleepiness and focus on encouraging drivers to respond to obvious indicators of fatigue and sleepiness and consequent increased crash risk. PMID:24803170

  6. Rural casualty crashes on the Kings Highway: A new approach for road safety studies.

    Science.gov (United States)

    Alian, Sahar; Baker, R G V; Wood, Stephen

    2016-10-01

    This paper will consider the contribution that changes in road geometry and driver visual information make to the incidence and distribution of road casualties in different driving environments. This relationship will be explored specifically for the Kings Highway, a major arterial road connecting Queanbeyan with coastal southern New South Wales, Australia. It introduces and suggests a new empirical approach of plotting crashes with road segmentation, calculating sinuosity indices and grades as key features of road geometry, and critical visual points as a behavioural component of road curvature, within a GIS context. It is an approach that might be used when detailed road geometry data is not available. The visualisation and segmentation approach in this research might be used for summarising crash rates and road geometry factors, and for comparing day/night and eastbound/westbound driving conditions. The results suggest some early interpretations for detailed road safety studies that might be considered at local or national levels. The rate of crashes increases according to changes in road geometry factors during the day and for eastbound travel. This is not the case for night driving where the incidence of crashes is similar on both straight and curved roads segments due to the headlight effect and limited background visual field. Crash clusters at day-time may be due to the stronger effect of road geometry (e.g. combination of curvature and vertical grade) on driver behaviour travelling eastbound. The outcomes suggest that it might be essential to consider the effect of environmental factors in any road safety and crash analysis studies. PMID:27372441

  7. A multinomial logit model-Bayesian network hybrid approach for driver injury severity analyses in rear-end crashes.

    Science.gov (United States)

    Chen, Cong; Zhang, Guohui; Tarefder, Rafiqul; Ma, Jianming; Wei, Heng; Guan, Hongzhi

    2015-07-01

    Rear-end crash is one of the most common types of traffic crashes in the U.S. A good understanding of its characteristics and contributing factors is of practical importance. Previously, both multinomial Logit models and Bayesian network methods have been used in crash modeling and analysis, respectively, although each of them has its own application restrictions and limitations. In this study, a hybrid approach is developed to combine multinomial logit models and Bayesian network methods for comprehensively analyzing driver injury severities in rear-end crashes based on state-wide crash data collected in New Mexico from 2010 to 2011. A multinomial logit model is developed to investigate and identify significant contributing factors for rear-end crash driver injury severities classified into three categories: no injury, injury, and fatality. Then, the identified significant factors are utilized to establish a Bayesian network to explicitly formulate statistical associations between injury severity outcomes and explanatory attributes, including driver behavior, demographic features, vehicle factors, geometric and environmental characteristics, etc. The test results demonstrate that the proposed hybrid approach performs reasonably well. The Bayesian network reference analyses indicate that the factors including truck-involvement, inferior lighting conditions, windy weather conditions, the number of vehicles involved, etc. could significantly increase driver injury severities in rear-end crashes. The developed methodology and estimation results provide insights for developing effective countermeasures to reduce rear-end crash injury severities and improve traffic system safety performance. PMID:25888994

  8. 77 FR 46154 - Announcing the Twentieth Public Meeting of the Crash Injury Research and Engineering Network (CIREN)

    Science.gov (United States)

    2012-08-02

    ...This notice announces the Twentieth Public Meeting of members of the Crash Injury Research and Engineering Network. CIREN is a collaborative effort to conduct research on crashes and injuries at six Level I Trauma Centers across the United States linked by a computer network. The current CIREN model utilizes two types of centers, medical and engineering. Medical centers are based at Level I......

  9. Airplane crash modelling: assessment of the riera model

    International Nuclear Information System (INIS)

    The Riera approach is the most common method of defining a loading curve of a missile impacting a structure. After a brief reminder of the Riera assumptions (soft crash for crushed parts, instantaneous deceleration of uncrushed part due to local crushing strength of crushing part), some physical insights are developed. According to this model, the loading curve F(x, t), where the section S(x) at distance x (x=x (t)) from missile nose is under crushing, is given by the sum of a term Re(x), corresponding to the mechanical crushing strength of the section S(x), and of a term μ(x)*v(t)2, corresponding to the inertial force exerted at section S(x) by mass elements of density μ(x), whose velocity decreases from v to zero. Some analytical considerations are proposed regarding the missile motion when impacting a rigid target and its energy dissipation. Results from models of missile and target structures performed with the fast dynamic Finite Element code RADIOSS are used to assess the robustness, accuracy and limits of Riera model. Significant discrepancies between these approaches are found for commercial aircraft. Models by fast dynamic explicit code display loading curves characterised by higher and sharper peaks, whereas the velocity decrease of the uncrushed part is delayed. Riera model assumptions are therefore questioned and analysed. Those discrepancies are mainly due to higher distribution peaks of crushing strength and mass density and due to some hard inclusions in aircraft structure, like the engines and the junction of wing to fuselage. Soft impact is no longer relevant for such parts, whose action is then characterised by high peaks of short duration. When rounding the loading curve and spreading the impact area, the shear rupture is underestimated. Regarding concrete damaging, the Riera approach appears too optimistic. In order to keep the simplicity of the Riera approach and to improve its accuracy, the authors propose to evaluate the loading curve by

  10. HTR confinement/containment and the protection against aircraft crash

    International Nuclear Information System (INIS)

    during accidental conditions), the diffusion data, the dust data and the deposition/lift off mechanisms. For modern modular HTRs, the last confinement barrier performances will have to be determined in accordance with the set of accidents to be considered in the design including internal and external hazards and the limits targeted for the public and the environment protection. Further more the paper presents an analysis of effects of a deliberate crash of a large commercial airliner on a former German HTR design. (authors)

  11. Exploring the effects of roadway characteristics on the frequency and severity of head-on crashes: case studies from Malaysian federal roads.

    Science.gov (United States)

    Hosseinpour, Mehdi; Yahaya, Ahmad Shukri; Sadullah, Ahmad Farhan

    2014-01-01

    Head-on crashes are among the most severe collision types and of great concern to road safety authorities. Therefore, it justifies more efforts to reduce both the frequency and severity of this collision type. To this end, it is necessary to first identify factors associating with the crash occurrence. This can be done by developing crash prediction models that relate crash outcomes to a set of contributing factors. This study intends to identify the factors affecting both the frequency and severity of head-on crashes that occurred on 448 segments of five federal roads in Malaysia. Data on road characteristics and crash history were collected on the study segments during a 4-year period between 2007 and 2010. The frequency of head-on crashes were fitted by developing and comparing seven count-data models including Poisson, standard negative binomial (NB), random-effect negative binomial, hurdle Poisson, hurdle negative binomial, zero-inflated Poisson, and zero-inflated negative binomial models. To model crash severity, a random-effect generalized ordered probit model (REGOPM) was used given a head-on crash had occurred. With respect to the crash frequency, the random-effect negative binomial (RENB) model was found to outperform the other models according to goodness of fit measures. Based on the results of the model, the variables horizontal curvature, terrain type, heavy-vehicle traffic, and access points were found to be positively related to the frequency of head-on crashes, while posted speed limit and shoulder width decreased the crash frequency. With regard to the crash severity, the results of REGOPM showed that horizontal curvature, paved shoulder width, terrain type, and side friction were associated with more severe crashes, whereas land use, access points, and presence of median reduced the probability of severe crashes. Based on the results of this study, some potential countermeasures were proposed to minimize the risk of head-on crashes. PMID:24172088

  12. Missile crash simulation with the computer program HEMP-ESI. Pt. 1 and 2

    International Nuclear Information System (INIS)

    The goal of the study is to simulate by a precalculation the crash of a soft cylindrical missile on reinforced concrete slabs. The corresponding experiments will be performed at the Meppen test facilities (West Germany). The study has shown that the program used (HEMP-ESI with explicit finite difference zones and finite shells) can realistically simulate the crash problem when three phenomena were correctly controlled. The actual comparison with the experiments will allow a quantitative evaluation of the numerical model. The main results for the two cases are given. (orig./HP)

  13. Effect of forming rate on the impact tensile properties of the steels under crash test

    OpenAIRE

    Grumbach, M; Bayraktar, E.; Kaplan, D.(Department of Physics, Illinois Institute of Technology, Chicago, Illinois, 60616, U.S.A.)

    2007-01-01

    Purpose: The main objective of this study is to examine the mechanical and metallurgical behaviour of thetailored blanks and base metals for thin sheet steels used in the car industry by using a new type of crash test/impact (ITT). It exposes the effect of forming rate on the toughness of thin welded joints (tailored blanks) forInterstitial Free (IFS) steels used in the automotive industry.Design/methodology/approach: A special crash test device is used in different temperature and the simula...

  14. Firefly Optimization and Mathematical Modeling of a Vehicle Crash Test Based on Single-Mass

    OpenAIRE

    Andreas Klausen; Sondre Sanden Tørdal; Hamid Reza Karimi; Robbersmyr, Kjell G.; Mladen Jecmenica; Ole Melteig

    2014-01-01

    In this paper mathematical modeling of a vehicle crash test based on a single-mass is studied. The model under consideration consists of a single-mass coupled with a spring and/or a damper. The parameters for the spring and damper are obtained by analyzing the measured acceleration in the center of gravity of the vehicle during a crash. A model with a nonlinear spring and damper is also proposed and the parameters will be optimized with different damper and spring characteristics and optimiza...

  15. Frontal Crash Analysis of a Fully Detailed Car Model Based on Finite Element Method

    Institute of Scientific and Technical Information of China (English)

    Han Shan-Ling; Zhu Ping; Lin Zhong-Qin; Shi Yu-Liang

    2004-01-01

    This paper sets up a highly detailed finite element model of a car for frontal crashworthiness applications, and then explains the characteristics of it. The geometry model is preprocessed by Hypermesh software. The finite element method solver program selected for the simulation is LS-DYNA. After the crash simulation is carefully analyzed, the frontal crash experiment is aimed to validate the finite element model. The simulation results are basically in agreement with the experimental results. The validation of the finite element model is crucial for the further research in optimization of the automotive structure or lightweighting of the vehicle.

  16. Time-Efficient Read/Write Register in Crash-prone Asynchronous Message-Passing Systems

    OpenAIRE

    Mostefaoui, Achour; Raynal, Michel

    2016-01-01

    The atomic register is certainly the most basic object of computing science. Its implementation on top of an n-process asynchronous message-passing system has received a lot of attention. It has been shown that t \\textless{} n/2 (where t is the maximal number of processes that may crash) is a necessary and sufficient requirement to build an atomic register on top of a crash-prone asynchronous message-passing system. Considering such a context, this paper visits the notion of a fast implementa...

  17. The Grushin plane and quasiconformal Jacobians

    OpenAIRE

    Meyerson, William

    2011-01-01

    We construct a quasiconformal map from the Grushin plane to the Euclidean plane. Then, we generalize the Grushin plane slightly and explain how the Grushin plane can serve as an intermediary in dealing with quasiconformal maps on Euclidean spaces. In particular, we construct a family of quasiconformal embeddings of the Euclidean plane into larger Euclidean spaces whose Jacobians fail to be locally integrable on a line.

  18. Adjusting for car occupant injury liability in relation to age, speed limit, and gender-specific driver crash involvement risk.

    Science.gov (United States)

    Keall, Michael; Frith, William

    2004-12-01

    It is well established that older drivers' fragility is an important factor associated with higher levels of fatal crash involvement for older drivers. There has been less research on age-related fragility with respect to the sort of minor injuries that are more common in injury crashes. This study estimates a quantity that is related to injury fragility: the probability that a driver or a passenger of that driver will be injured in crashes involving two cars. The effects of other factors apart from drivers' fragility are included in this measure, including the fragility of the passengers, the crashworthiness of cars driven, seatbelt use by the occupants, and characteristics of crashes (including configuration and impact speed). The car occupant injury liability estimates appropriately includes these factors to adjust risk curves by age, gender, and speed limit accounting for overrepresentation in crashes associated with fragility and these other factors. PMID:15545071

  19. The general relativistic infinite plane

    CERN Document Server

    Jones, Preston; Ragsdale, Michael; Singleton, Douglas

    2007-01-01

    Uniform fields are one of the simplest and most pedagogically useful examples in introductory courses on electrostatics or Newtonian gravity. In general relativity there have been several proposals as to what constitutes a uniform field. In this article we examine two metrics that can be considered the general relativistic version of the infinite plane with finite mass per unit area. The first metric is the 4D version of the 5D "brane" world models which are the starting point for many current research papers. The second case is the cosmological domain wall metric. We examine to what extent these different metrics match or deviate from our Newtonian intuition about the gravitational field of an infinite plane. These solutions provide the beginning student in general relativity both computational practice and conceptual insight into Einstein's field equations. In addition they do this by introducing the student to material that is at the forefront of current research.

  20. Plane waves as tractor beams

    CERN Document Server

    Forgács, Péter; Romańczukiewicz, Tomasz

    2013-01-01

    It is shown that in a large class of systems plane waves can act as tractor beams: i.e., an incident plane wave can exert a pulling force on the scatterer. The underlying physical mechanism for the pulling force is due to the sufficiently strong scattering of the incoming wave into another mode having a larger wave number, in which case excess momentum is created behind the scatterer. Such a tractor beam or negative radiation pressure effect arises naturally in systems where the coupling between the scattering channels is due to Aharonov-Bohm (AB) gauge potentials. It is demonstrated that this effect is also present if the AB potential is an induced, ("artificial") gauge potential such as the one found in J. March-Russell, J. Preskill, F. Wilczek, Phys. Rev. Lett. 58 2567 (1992).

  1. 41 CFR 102-34.290 - What forms do I use to report a crash involving a domestic fleet motor vehicle?

    Science.gov (United States)

    2010-07-01

    ... report a crash involving a domestic fleet motor vehicle? 102-34.290 Section 102-34.290 Public Contracts... forms do I use to report a crash involving a domestic fleet motor vehicle? Use the following forms to report a domestic fleet crash. The forms should be carried in any domestic fleet motor vehicle....

  2. Twisted sectors from plane partitions

    CERN Document Server

    Datta, Shouvik; Li, Wei; Peng, Cheng

    2016-01-01

    Twisted sectors arise naturally in the bosonic higher spin CFTs at their free points, as well as in the associated symmetric orbifolds. We identify the coset representations of the twisted sector states using the description of W_\\infty representations in terms of plane partitions. We confirm these proposals by a microscopic null-vector analysis, and by matching the excitation spectrum of these representations with the orbifold prediction.

  3. Plane SPDC-Quantum Mirror

    OpenAIRE

    Ion, M. L. D.; Ion, D. B.

    2013-01-01

    In this paper the kinematical correlations from the phase conjugated optics (equivalently with crossing symmetric spontaneous parametric down conversion (SPDC) phenomena) in the nonlinear crystals are used for the description of a new kind of optical device called SPDC-quantum mirrors. Then, some important laws of the plane SPDC-quantum mirrors combined with usual mirrors or lens are proved only by using geometric optics concepts. In particular, these results allow us to obtain a new interpre...

  4. Force Lines in Plane Stress

    OpenAIRE

    Rathkjen, Arne

    1994-01-01

    A state of plane stress is illustrated by means of two families of curves, each family representing constant values of a derivative of Airy's stress function. The two families of curves form a map giving in the first place an overall picture of regions of high and low stress, and in the second place, the map comprises a complete graphic representation of the stress at any point.

  5. Using naturalistic driving data to explore the association between traffic safety-related events and crash risk at driver level.

    Science.gov (United States)

    Wu, Kun-Feng; Aguero-Valverde, Jonathan; Jovanis, Paul P

    2014-11-01

    There has been considerable research conducted over the last 40 years using traffic safety-related events to support road safety analyses. Dating back to traffic conflict studies from the 1960s these observational studies of driver behavior have been criticized due to: poor quality data; lack of available and useful exposure measures linked to the observations; the incomparability of self-reported safety-related events; and, the difficulty in assessing culpability for safety-related events. This study seeks to explore the relationships between driver characteristics and traffic safety-related events, and between traffic safety-related events and crash involvement while mitigating some of those limitations. The Virginia Tech Transportation Institute 100-Car Naturalistic Driving Study dataset, in which the participants' vehicles were instrumented with various cameras and sensors during the study period, was used for this study. The study data set includes 90 drivers observed for 12-13 months driving. This study focuses on single vehicle run-off-road safety-related events only, including 14 crashes and 182 safety-related events (30 near crashes, and 152 crash-relevant incidents). Among the findings are: (1) drivers under age 25 are significantly more likely to be involved in safety-related events and crashes; and (2) significantly positive correlations exist between crashes, near crashes, and crash-relevant incidents. Although there is still much to learn about the factors affecting the positive correlation between safety-related events and crashes, a Bayesian multivariate Poisson log-normal model is shown to be useful to quantify the associations between safety-related events and crash risk while controlling for driver characteristics. PMID:25086439

  6. Air ionization wire plane chamber

    International Nuclear Information System (INIS)

    Radiation Measurement for protection level instrumentation requires large number of detectors. Since the number is large, the detector should be cost effective and yet should have good sensitivity. Gas detectors with presently available microelectronics and signal processing capabilities opened a new era in radiation monitoring. Present paper describes the use of air filled multi anode grid planes as detector for alpha detection. Due to multiple anode wire planes, the charge collection efficiency of the air ionization chamber is higher as compared to conventional ionization chamber. The signal from this Wire Plane Chamber (WPC) has a faster and narrower pulse shape as compared to conventional two-electrode chamber of similar dimensions. The reduction in capacitance also improves the signal to noise ratio so that air can be used as the ionization medium without any special cleaning procedure etc and it may be possible to use even engineering plastic as the structural material for the chamber. The paper gives the results obtained so far with this air ionization chamber. (author)

  7. Generalized plane gravitational waves of non-symmetric unified field theories in plane symmetry

    OpenAIRE

    Bhoyar, Sanjiv R.; Ajit Deshmukh

    2012-01-01

    In this paper we investigated the plane wave solutions of both the weak and strong non-symmetric unified field equations of Einstein and Bonner in a generalized plane symmetric space-time in the sense of Taub [Ann. Math. 53, 472 (1951)] for plane gravitational waves. We show that the plane wave solutions of Einstein and Bonner field equations exist in plane symmetry.

  8. Plane wave diffraction by a perfectly transparent half-plane.

    Science.gov (United States)

    Anokhov, Sergey P

    2007-09-01

    The exact solution is found for plane wave diffraction by an arbitrary phase step. The analysis is performed by using the Huygens-Fresnel principle and the superposition integral, where every secondary wave was identified with the surface element field of the actual electromagnetic wave. The dependence of the total field structure on the height of the phase step is analyzed. The formation algorithm is demonstrated for the primary wave component of the edge diffraction, which has a singular nature and determines nearly all physical properties of this phenomenon. PMID:17767219

  9. The application of the random regret minimization model to drivers’ choice of crash avoidance maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    (GES) crash database for the period between 2005 and 2009. The predictive ability of the RRM-based model is slightly superior to its RUM-based counterpart, namely the multinomial logit model (MNL) model. The marginal effects predicted by the RRM-based model are greater than those predicted by the RUM...

  10. The application of the random regret minimization model to drivers’ choice of crash avoidance maneuvers

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2012-01-01

    (GES) crash database for the period between 2005 and 2009. The predictive ability of the RRM-based model is slightly superior to its RUM-based counterpart, namely the multinomial logit model (MNL) model. The marginal effects predicted by the RRM-based model are greater than those predicted by the RUM...

  11. Fatal Crashes from Drivers Testing Positive for Drugs in the U.S., 1993–2010

    Science.gov (United States)

    Stimpson, Jim P.; Pagán, José A.

    2014-01-01

    Objective Illegal drug use is a persistent problem, prescription drug abuse is on the rise, and there is clinical evidence that drug use reduces driving performance. This study describes trends in characteristics of drivers involved in fatal motor vehicle crashes who test positive for drugs. Methods We used the Fatality Analysis Reporting System—a census of motor vehicle crashes resulting in at least one fatality on U.S. public roads—to investigate suspected drug use for the period 1993–2010. Results Drugged drivers who were tested for drug use accounted for 11.4% of all drivers involved in fatal motor vehicle crashes in 2010. Drugged drivers are increasingly likely to be older drivers, and the percentage using multiple drugs increased from 32.6% in 1993 to 45.8% in 2010. About half (52.4%) of all drugged drivers used alcohol, but nearly three-quarters of drivers testing positive for cocaine also used alcohol. Prescription drugs accounted for the highest fraction of drugs used by drugged drivers in fatal crashes in 2010 (46.5%), with much of the increase in prevalence occurring since the mid-2000s. Conclusions The profile of a drugged driver has changed substantially over time. An increasing share of these drivers is now testing positive for prescription drugs, cannabis, and multiple drugs. These findings have implications for developing interventions to address the changing nature of drug use among drivers in the U.S. PMID:24982537

  12. Crash Testing in the Lab: Putting a New Stop to the CO2 Car!

    Science.gov (United States)

    Decker, Rob

    2005-01-01

    Every year in the United States, the federal government, insurance companies and automobile manufacturers wreck hundreds of cars for safety-testing purposes. All this crashing comes in an effort to rate vehicular safety for the public. Inspired by numerous movies with car chases, dramatic wrecks and television commercials showing car safety tests,…

  13. Diagnostic analysis of the logistic model for pedestrian injury severity in traffic crashes.

    Science.gov (United States)

    Sze, N N; Wong, S C

    2007-11-01

    This study attempts to evaluate the injury risk of pedestrian casualties in traffic crashes and to explore the factors that contribute to mortality and severe injury, using the comprehensive historical crash record that is maintained by the Hong Kong Transport Department. The injury, demographic, crash, environmental, geometric, and traffic characteristics of 73,746 pedestrian casualties that were involved in traffic crashes from 1991 to 2004 are considered. Binary logistic regression is used to determine the associations between the probability of fatality and severe injury and all contributory factors. A consideration of the influence of implicit attributes on the trend of pedestrian injury risk, temporal confounding, and interaction effects is progressively incorporated into the predictive model. To verify the goodness-of-fit of the proposed model, the Hosmer-Lemeshow test and logistic regression diagnostics are conducted. It is revealed that there is a decreasing trend in pedestrian injury risk, controlling for the influences of demographic, road environment, and other risk factors. In addition, the influences of pedestrian behavior, traffic congestion, and junction type on pedestrian injury risk are subject to temporal variation. PMID:17920851

  14. Brace for impact! A thesis on medical care following an airplane crash

    NARCIS (Netherlands)

    I.L.E. Postma

    2014-01-01

    In this thesis the events and management of a mass casualty incident (MCI) of an airplane crash are studied from a medical point of view. The incident is broken down into areas that are applicable to other MCIs. it is believed that the detailed study of an exceptional event can provide vital informa

  15. Time series of stock price and of two fractal overlap: Anticipating market crashes?

    CERN Document Server

    Chakrabarti, Bikas K; Bhattacharya, P; Chakrabarti, Bikas K.; Chatterjee, Arnab; Bhattacharyya, Pratip

    2005-01-01

    We find prominent similarities in the features of the time series for the overlap of two Cantor sets when one set moves with uniform relative velocity over the other and time series of stock prices. An anticipation method for some of the crashes have been proposed here, based on these observations.

  16. Analysis of factors associated with injury severity in crashes involving young New Zealand drivers

    DEFF Research Database (Denmark)

    Weiss, Harold B.; Kaplan, Sigal; Prato, Carlo Giacomo

    2014-01-01

    fit than a binary and a generalized ordered logit. Results show that the young drivers’ behavior, the presence of passengers and the involvement of vulnerable road users were the most relevant factors associated with higher injury severity in both single-vehicle and two-vehicle crashes. Seatbelt non...

  17. Clustering, concurrency control, crash recovery, garbage collection, and security in object-oriented database management systems

    OpenAIRE

    de Paula, Everton, G.; Nelson, Michael L.

    1991-01-01

    This paper presents considerations about several topics that have a direct influence on data reliability and performance in object oriented database management systems. These topics are: physical storage management (clustering), concurrency control, crash recovery, garbage collection, and database security. Each topic is illustrated by its application to the Tactical Database as designed for the Low Cost Combat Direction System

  18. Sample-size guidelines for recalibrating crash prediction models: Recommendations for the highway safety manual.

    Science.gov (United States)

    Shirazi, Mohammadali; Lord, Dominique; Geedipally, Srinivas Reddy

    2016-08-01

    The Highway Safety Manual (HSM) prediction models are fitted and validated based on crash data collected from a selected number of states in the United States. Therefore, for a jurisdiction to be able to fully benefit from applying these models, it is necessary to calibrate or recalibrate them to local conditions. The first edition of the HSM recommends calibrating the models using a one-size-fits-all sample-size of 30-50 locations with total of at least 100 crashes per year. However, the HSM recommendation is not fully supported by documented studies. The objectives of this paper are consequently: (1) to examine the required sample size based on the characteristics of the data that will be used for the calibration or recalibration process; and, (2) propose revised guidelines. The objectives were accomplished using simulation runs for different scenarios that characterized the sample mean and variance of the data. The simulation results indicate that as the ratio of the standard deviation to the mean (i.e., coefficient of variation) of the crash data increases, a larger sample-size is warranted to fulfill certain levels of accuracy. Taking this observation into account, sample-size guidelines were prepared based on the coefficient of variation of the crash data that are needed for the calibration process. The guidelines were then successfully applied to the two observed datasets. The proposed guidelines can be used for all facility types and both for segment and intersection prediction models. PMID:27183517

  19. Reduced fertility after the crash of a U.S. bomber carrying nuclear weapons?

    DEFF Research Database (Denmark)

    Juel, K

    1995-01-01

    A register-based study was performed to elucidate whether workers employed on the Thule air base in the clean-up period after the crash of a U.S. B-52 bomber carrying nuclear bombs had reduced fertility, as measured by the numbers of liveborn children. The highest birth rates were among 25-34-year...

  20. Real-time wavelet detection of crashes in limit cycles of non-stationary fusion plasmas

    NARCIS (Netherlands)

    Berkel, M. van; Witvoet, G.; Baar, M.R. de; Nuij, P.W.J.M.; Morsche, H.G. ter; Steinbuch, M.

    2011-01-01

    The high performance mode(H-mode)is one of the baseline plasma scenarios for the experimental fusion reactor ITER. This scenario features a periodic crash-like reorganization of the plasma pressure and the magnetic flux in the plasmacore and plasma periphery. The core instability is often referred t

  1. Sport cycling crashes on public roads, the influence of bunch riding and experience.

    NARCIS (Netherlands)

    Wijlhuizen, G.J. Gent, P. van & Stipdonk, H.L.

    2014-01-01

    Cycling is a popular but unsafe mode of transport in the Netherlands and the number of seriously injured bicyclists has increased significantly since 2006. A special subgroup is the population of sport cyclists who perform their sport on public roads. The number of road crashes with sport cyclists s

  2. Brace for impact! A thesis on medical care following an airplane crash

    OpenAIRE

    Goslings, J.C.; Bloemers, F.W.; Bijlsma, T.S.; Heetveld, M.J.; Postma, I.L.E.

    2014-01-01

    In this thesis the events and management of a mass casualty incident (MCI) of an airplane crash are studied from a medical point of view. The incident is broken down into areas that are applicable to other MCIs. it is believed that the detailed study of an exceptional event can provide vital information for many other kinds of exceptional events.

  3. Frequency Estimates for Aircraft Crashes into Nuclear Facilities at Los Alamos National Laboratory (LANL)

    Energy Technology Data Exchange (ETDEWEB)

    George D. Heindel

    1998-09-01

    In October 1996, the Department of Energy (DOE) issued a new standard for evaluating accidental aircraft crashes into hazardous facilities. This document uses the method prescribed in the new standard to evaluate the likelihood of this type of accident occurring at Los Alamos National Laboratory's nuclear facilities.

  4. Classification of soft and hard impacts-Application to aircraft crash

    International Nuclear Information System (INIS)

    Before modeling an aircraft crash on a shield building of a nuclear power plant, it is very important to understand the physical phenomena and the structural behavior associated with this kind of impact. In the scientific literature, aircraft crash is classified as a soft impact, or as an impact of deformable missile. Nevertheless the existing classifications are not precise enough to be able to predict 'a priori' the structural response mode. The aim of this paper is to characterize very precisely what is a soft and a hard impact in the frame of aircraft crash on nuclear power plant. First the existing qualitative definition of soft and hard impact is quickly reviewed in order to introduce a new criterion to make a quantitative distinction between soft and hard impact. Then the experimental tests carried out during the last thirty years in the research field of aircraft crash are presented in the light of the new classification. The authors show that this characterization of soft and hard impacts has a real physical interest because it is linked to the failure mode for perforation: for soft impacts, perforation is the consequence of a shear plug breaking away and for hard impact it comes from local failure and projectile penetration. Moreover the boundary between soft and hard impact is the limit for the use of an impact force in an uncoupled computation of the impact

  5. Occupant Responses in a Full-Scale Crash Test of the Sikorsky ACAP Helicopter

    Science.gov (United States)

    Jackson, Karen E.; Fasanella, Edwin L.; Boitnott, Richard L.; McEntire, Joseph; Lewis, Alan

    2002-01-01

    A full-scale crash test of the Sikorsky Advanced Composite Airframe Program (ACAP) helicopter was performed in 1999 to generate experimental data for correlation with a crash simulation developed using an explicit nonlinear, transient dynamic finite element code. The airframe was the residual flight test hardware from the ACAP program. For the test, the aircraft was outfitted with two crew and two troop seats, and four anthropomorphic test dummies. While the results of the impact test and crash simulation have been documented fairly extensively in the literature, the focus of this paper is to present the detailed occupant response data obtained from the crash test and to correlate the results with injury prediction models. These injury models include the Dynamic Response Index (DRI), the Head Injury Criteria (HIC), the spinal load requirement defined in FAR Part 27.562(c), and a comparison of the duration and magnitude of the occupant vertical acceleration responses with the Eiband whole-body acceleration tolerance curve.

  6. Plane SPDC-Quantum Mirror

    CERN Document Server

    Ion, M L D

    2013-01-01

    In this paper the kinematical correlations from the phase conjugated optics (equivalently with crossing symmetric spontaneous parametric down conversion (SPDC) phenomena) in the nonlinear crystals are used for the description of a new kind of optical device called SPDC-quantum mirrors. Then, some important laws of the plane SPDC-quantum mirrors combined with usual mirrors or lens are proved only by using geometric optics concepts. In particular, these results allow us to obtain a new interpretation of the recent experiments on the two-photon geometric optics.

  7. Distributed Storage in the Plane

    OpenAIRE

    Altman, Eitan; Avrachenkov, Konstantin; Goseling, Jasper

    2014-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can contact the storage devices to retrieve the data.We compare the expected cost of obtaining the complete data under uncoded as well as coded data allocation strategies. It is shown that for the gen...

  8. Semantic versus syntactic cutting planes

    Czech Academy of Sciences Publication Activity Database

    Filmus, Y.; Hrubeš, Pavel; Lauria, M.

    Dagstuhl: Schloss Dagstuhl, Leibniz-Zentrum für Informatik, 2016 - (Ollinger, N.; Vollmer, H.), s. 1-13. (Leibniz International Proceedings in Informatics. 47). ISBN 978-3-95977-001-9. ISSN 1868-8969. [33rd Symposium on Theoretical Aspects of Computer Science (STACS 2016). Orléans (FR), 17.02.2016-20.02.2016] EU Projects: European Commission(XE) 339691 - FEALORA Keywords : proof complexity * cutting planes * lower bounds Subject RIV: BA - General Mathematics http://drops.dagstuhl.de/opus/frontdoor.php?source_opus=5736

  9. Plane waves in noncommutative fluids

    CERN Document Server

    Holender, M C B AbdallaL; Vancea, I V

    2012-01-01

    We study the dynamics of the noncommutative fluid in the Snyder space from the perturbative point of view. To this end, the relevant quantities are treated as series in powers of the noncommutative parameter. At the Planck scale, the relevant terms are of first order and the dynamics is described by a system of coupled linear partial differential equations in which the variables are the fluid density and the fluid potentials. We show that these equations admit a set of solutions that are monocromatic plane waves for the fluid density and two of the potentials and linear for the third potential. The energy-momentum tensor of these solutions is calculated.

  10. SNAP Satellite Focal Plane Development

    International Nuclear Information System (INIS)

    The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R and D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to advance our preparedness for mission proposal in the areas of detectors and electronics

  11. Combinatorial geometry in the plane

    CERN Document Server

    Hadwiger, Hugo; Klee, Victor

    2014-01-01

    Geared toward advanced undergraduates familiar with analysis and college geometry, this concise book discusses theorems on topics restricted to the plane such as convexity, coverings, and graphs. In addition to helping students cultivate rigorous thought, the text encourages the development of mathematical intuition and clarifies the nature of mathematical research.The two-part treatment begins with specific topics including integral distances, covering problems, point set geometry and convexity, simple paradoxes involving point sets, and pure combinatorics, among other subjects. The second pa

  12. Constructing a uniform plane-filling path in the ternary heptagrid of the hyperbolic plane

    OpenAIRE

    Maurice Margenstern

    2007-01-01

    In this paper, we distinguish two levels for the plane-filling property. We consider a simple and a strong one. In this paper, we give the construction which proves that the simple plane-filling property also holds for the hyperbolic plane. The plane-filling property was established for the Euclidean plane by J. Kari, see [2], in the strong version. We also give an application of the construction to devise a Peano curve in the hyperbolic plane.

  13. Differences in passenger car and large truck involved crash frequencies at urban signalized intersections: an exploratory analysis.

    Science.gov (United States)

    Dong, Chunjiao; Clarke, David B; Richards, Stephen H; Huang, Baoshan

    2014-01-01

    The influence of intersection features on safety has been examined extensively because intersections experience a relatively large proportion of motor vehicle conflicts and crashes. Although there are distinct differences between passenger cars and large trucks-size, operating characteristics, dimensions, and weight-modeling crash counts across vehicle types is rarely addressed. This paper develops and presents a multivariate regression model of crash frequencies by collision vehicle type using crash data for urban signalized intersections in Tennessee. In addition, the performance of univariate Poisson-lognormal (UVPLN), multivariate Poisson (MVP), and multivariate Poisson-lognormal (MVPLN) regression models in establishing the relationship between crashes, traffic factors, and geometric design of roadway intersections is investigated. Bayesian methods are used to estimate the unknown parameters of these models. The evaluation results suggest that the MVPLN model possesses most of the desirable statistical properties in developing the relationships. Compared to the UVPLN and MVP models, the MVPLN model better identifies significant factors and predicts crash frequencies. The findings suggest that traffic volume, truck percentage, lighting condition, and intersection angle significantly affect intersection safety. Important differences in car, car-truck, and truck crash frequencies with respect to various risk factors were found to exist between models. The paper provides some new or more comprehensive observations that have not been covered in previous studies. PMID:24140813

  14. Trait Predictors of Aggression and Crash-Related Behaviors Across Drivers from the United Kingdom and the Irish Republic.

    Science.gov (United States)

    Stephens, Amanda N; Sullman, Mark J M

    2015-09-01

    Aggressive driving is acknowledged as a contributor to motor vehicle crashes. This study explored a theoretical model of aggressive expression and crash-related outcomes using self-report data collected, using an online questionnaire, from drivers in the United Kingdom and the Republic of Ireland. The proposed model tested whether the personality traits of boredom proneness, sensation seeking, and impulsivity, coupled with trait driving anger, predicted aggressive driving; and whether aggressive driving predicted crash-related outcomes (loss of concentration and control, near misses, and moving violations). The structural model was confirmed, with aggressive expressions of anger being found to mediate the relationships driving anger and impulsivity had with the crash-related outcomes. Multigroup invariance analysis showed that the model remained invariant across drivers from the United Kingdom and Ireland, suggesting that the contributing factors for aggressive expression and crash involvement are similar across both countries. When self-reported crash-related conditions were compared between drivers in the United Kingdom and Ireland, drivers in the United Kingdom reported more aggressive driving, more minor crashes, more incidents of road rage, and more frequent losses of concentration and vehicle control. PMID:25809573

  15. Risk factors for causing road crashes involving cyclists: An application of a quasi-induced exposure method.

    Science.gov (United States)

    Martínez-Ruiz, Virginia; Lardelli-Claret, Pablo; Jiménez-Mejías, Eladio; Amezcua-Prieto, Carmen; Jiménez-Moleón, José Juan; Luna del Castillo, Juan de Dios

    2013-03-01

    A quasi-induced exposure approach was applied to the Spanish Register of Traffic Crashes to identify driver- and vehicle-related factors associated with the risk of causing a road crash involving a cyclist in Spain from 1993 to 2009. We analyzed 19,007 collisions between a bicycle and another vehicle in which only one of the drivers committed an infraction, and 13,540 records that included the group of non-infractor cyclists in the above collisions plus cyclists involved in single-bicycle crashes. Adjusted odds ratios were calculated for being responsible for each type of crash for each factor considered. Age from 10 to 19 years, male sex, alcohol or drug consumption and non-helmet use were cyclist-related variables associated with a higher risk of crash, whereas cycling more than 1h increased only the risk of single crashes. Bicycles with brake defects and ridden by two occupants were also at higher risk of involvement in a crash, whereas light defects were associated only with collisions with another vehicle. For drivers of the other vehicle, age more than 60 years, alcohol, not using safety devices and nonprofessional drivers were at higher risk. The risk of colliding with a bicycle was higher for mopeds than for passenger cars. PMID:23274281

  16. Emergency Locator Transmitter System Performance During Three Full-Scale General Aviation Crash Tests

    Science.gov (United States)

    Littell, Justin D.; Stimson, Chad M.

    2016-01-01

    Full-scale crash tests were conducted on three Cessna 172 aircraft at NASA Langley Research Center's Landing and Impact Research facility during the summer of 2015. The purpose of the three tests was to evaluate the performance of commercially available Emergency Locator Transmitter (ELT) systems and support development of enhanced installation guidance. ELTs are used to provide location information to Search and Rescue (SAR) organizations in the event of an aviation distress situation, such as a crash. The crash tests simulated three differing severe but survivable crash conditions, in which it is expected that the onboard occupants have a reasonable chance of surviving the accident and would require assistance from SAR personnel. The first simulated an emergency landing onto a rigid surface, while the second and third simulated controlled flight into terrain. Multiple ELT systems were installed on each airplane according to federal regulations. The majority of the ELT systems performed nominally. In the systems which did not activate, post-test disassembly and inspection offered guidance for non-activation cause in some cases, while in others, no specific cause could be found. In a subset of installations purposely disregarding best practice guidelines, failure of the ELT-to-antenna cabling connections were found. Recommendations for enhanced installation guidance of ELT systems will be made to the Radio Technical Commission for Aeronautics (RTCA) Special Committee 229 for consideration for adoption in a future release of ELT minimum operational performance specifications. These recommendations will be based on the data gathered during this test series as well as a larger series of crash simulations using computer models that will be calibrated based on these data

  17. Calibration of safety performance function for crashes on inter-city four lane highways in India

    Directory of Open Access Journals (Sweden)

    Naveen Kumar ChikkaKrishna

    2015-12-01

    Full Text Available There is a significant need to improve the highway safety during roadway planning, design and operations in developing countries like India. To receive appropriate consideration, safety needs to be dealt objectively within the transportation planning and highway design processes. Lack of available tools is a deterrent to quantify safety of a transportation facility during the planning or highway design process. The objective of this paper is to develop safety performance functions considering various elements involved in the planning, design and operation of a section on four-lane National Highway (NH-58 located in the state of Uttarakhand, India. The mixed traffic on Indian multilane highways comes with a lot of variability within, ranging from different vehicle types to different driver characteristics. This could result in variability in the effect of explanatory variables on crashes across locations. Hence, explanatory variables for highway segment safety analysis considered were geometric characteristics like curvature change rate, slope change rate, transverse slope and traffic characteristics in the form of average daily traffic, light vehicle traffic, light commercial vehicle traffic, heavy vehicle traffic, two-wheelers, non-motorised traffic volume and operating speed were analysed against dependent variable as crash count per 200 m per year. Safety performance functions involving the explanatory variables are calibrated to predict crash frequency using Poisson Weibull technique and crash types are predicted using ordered logit model. Model results suggest that increase in traffic volume leads to higher probability of crash risk and traffic safety is significantly distorted by higher curvature change rate values.

  18. Contact Cohomology of the Projective Plane

    OpenAIRE

    Ernstr{ö}m, Lars; Kennedy, Gary

    1997-01-01

    We construct an associative ring which is a deformation of the quantum cohomology ring of the projective plane. Just as the quantum cohomology encodes the incidence characteristic numbers of rational plane curves, the contact cohomology encodes the tangency characteristic numbers.

  19. On free fermions and plane partitions

    OpenAIRE

    Foda, O.; Wheeler, M.; Zuparic, M.

    2008-01-01

    We use free fermion methods to re-derive a result of Okounkov and Reshetikhin relating charged fermions to random plane partitions, and to extend it to relate neutral fermions to strict plane partitions.

  20. On maps taking lines to plane curves

    OpenAIRE

    Petrushchenko, Vsevolod; Timorin, Vladlen

    2014-01-01

    We study cubic rational maps that take lines to plane curves. A complete description of such cubic rational maps concludes the classification of all planarizations, i.e., maps taking lines to plane curves.

  1. Catastrophic Equatorial Icing Caused the Air France 447 and Malaysian 370 Crashes: Risks of More Such Disasters Are Increased By Global Warming

    Science.gov (United States)

    Gibson, C. H.

    2014-12-01

    Dangerous icing conditions near the equator have been observed, and may account for the tragic crashes of Air France 447 in 2009 and Malaysian Airlines 370 in 2014, not pilot error in either case. Six cases of engine failures from icing were reported in 2013 at high altitudes for 747-8 and 787 Dreamliner planes at tropical latitudes (journalofcosmology.com volume 23). Lack of horizontal Coriolis forces accounts for the extreme intermittency of equatorial turbulence and turbulent mixing, Baker and Gibson (1987). Intermittency factors inferred from the available microstructure data sets were much larger than those at higher latitudes, reflecting the wide range of scales of the turbulence cascade from small scales to large in the horizontal direction. Lognormal statistical analysis implies mean values of dissipation rates are likely to be 30,000 times larger than mode values at the equator, compared to only 2000 times larger at midlatitudes. Modern stratified turbulence theory (journalofcosmology.com volume 21) shows turbulent mixing of heat, mass, momentum, and chemical species in natural fluids such as the ocean, atmosphere, and cosmological fluids is dominated by mixing chimneys directed perpendicular to vertical and radial layers of gravitational stratification by the inertial vortex forces that define turbulence. Rarely, thick columns of supercooled steam reach cruising altitudes of jet aircraft. After entering such a column, the plane is doomed.

  2. Post-crash management of road traffic injury victims in Iran. Stakeholders' views on current barriers and potential facilitators

    Directory of Open Access Journals (Sweden)

    Mohammadi Reza

    2009-05-01

    Full Text Available Abstract Background Road traffic injuries are a major public health problem, especially in low- and middle-income countries. Post-crash management can play a significant role in minimizing crash consequences and saving lives. Iran has one of the highest mortality rates from road traffic injuries in the world. The present study attempts to fill the knowledge gap and explores stakeholders' perceptions of barriers to – and facilitators of – effective post-crash management in Iranian regions. Methods Thirty-six semi-structured interviews were conducted with medical services personnel, police officers, members of Red Crescent, firefighters, public-health professionals, road administrators; some road users and traffic injury victims. A qualitative approach using grounded theory method was employed to analyze the material gathered. Results The core variable was identified as "poor quality of post crash management". Barriers to effective post-crash management were identified as: involvement of laypeople; lack of coordination; inadequate pre-hospital services; shortcomings in infrastructure. Suggestions for laypeople included: 1 a public education campaign in first aid, the role of the emergency services, cooperation of the public at the crash site, and 2 target-group training for professional drivers, police officers and volunteers involved at the crash scene. An integrated trauma system and infrastructure improvement also is crucial to be considered for effective post-crash management. Conclusion To sum up, it seems that the involvement of laypeople could be a key factor in making post-crash management more effective. But system improvements are also crucial, including the integration of the trauma system and its development in terms of human resources (staffing and training and physical resources as well as the infrastructure development.

  3. The half plane UIPT is recurrent

    OpenAIRE

    Angel, Omer; Ray, Gourab

    2016-01-01

    We prove that the half plane version of the uniform infinite planar triangulation (UIPT) is recurrent. The key ingredients of the proof are a construction of a new full plane extension of the half plane UIPT, based on a natural decomposition of the half plane UIPT into independent layers, and an extension of previous methods for proving recurrence of weak local limits (still using circle packings).

  4. Aspects of Plane Wave (Matrix) String Dynamics

    OpenAIRE

    Blau, Matthias; O'Loughlin, Martin; Seri, Lorenzo

    2011-01-01

    We analyse two issues that arise in the context of (matrix) string theories in plane wave backgrounds, namely (1) the use of Brinkmann- versus Rosen-variables in the quantum theory for general plane waves (which we settle conclusively in favour of Brinkmann variables), and (2) the regularisation of the quantum dynamics for a certain class of singular plane waves (discussing the benefits and limitations of regularisations of the plane-wave metric itself).

  5. The Bolocam Galactic Plane Survey

    Science.gov (United States)

    Glenn, Jason; Aguirre, James; Bally, John; Battersby, Cara; Bradley, Eric Todd; Cyganowski, Claudia; Dowell, Darren; Drosback, Meredith; Dunham, Miranda K.; Evans, Neal J., II; Ginsburg, Adam; Harvey, Paul; Rosolowsky, Erik; Schlingman, Wayne; Shirley, Yancy L.; Stringfellow, Guy S.; Walawender, Josh; Williams, Jonathan

    2009-01-01

    The Bolocam Galactic Plane Survey (BGPS) is a 1.1 millimeter continuum survey of the northern Galactic Plane made with Bolocam and the Caltech Submillimeter Observatory. The coverage totals 170 square degrees, comprised of a contiguous range from -10.5 deg is less than or equal to 90.5 deg, 0.5 deg is less than or equal to b is less than or equal to 0.5 deg, with extended coverage in b in selected regions, and four targeted regions in the outer Galaxy, including: IC1396, toward the Perseus arm at l is approximately 111 deg, W3/4/5, and Gem OB1. Depths of the maps range from 30 to 60 mJy beam (sup 1). Approximately 8,400 sources were detected and the maps and source catalog have been made publicly available. Millimeter-wave thermal dust emission reveals dense regions within molecular clouds, thus the BGPS serves as a database for studies of the dense interstellar medium and star formation within the Milky Way.

  6. The INTEGRAL Galactic Plane Scanning

    CERN Document Server

    Fiocchi, Mariateresa

    2013-01-01

    After the first nine years of INTEGRAL operational life, the discovery of new sources and source types, a large fraction of which are highly transient or highly absorbed, is certainly one of the most compelling results and legacies of INTEGRAL. Frequent monitoring of the Galactic Plane in AO8 and AO9 campaigns allowed us to detect transient sources, both known and new, confirming that the gamma-ray sky is dominated by the extreme variability of different classes of objects. Regular scans of the Galactic Plane by INTEGRAL provide the most sensitive hard X-ray wide survey to date of our Galaxy, with flux limits of the order of 0.3 mCrab for an exposure time of ~2Ms. Many transient sources have been detected on a wide range of time scales (~hours to months) and identified by triggered followup observations, mainly by Swift/XRT and optical/infrared telescopes. These discoveries are very important to characterize the X-ray binary population in our Galaxy, that is necessary input for evolution studies. The transien...

  7. The UKIDSS Galactic Plane Survey

    CERN Document Server

    Lucas, P W; Longmore, A; Schröder, A C; Davis, C J; Adamson, A; Bandyopadhyay, R M; De Grijs, R; Smith, M; Gosling, A; Mitchison, S; Gaspar, A; Coe, M; Tamura, M; Parker, Q; Irwin, M; Hambly, N; Byant, J; Collins, R S; Cross, N; Evans, D W; Gonzalez-Solares, E; Hodgkin, S; Lewis, J; Read, M; Riello, M; Sutorius, E T W; Lawrence, A; Drew, J E; Dye, S

    2007-01-01

    The UKIDSS Galactic Plane Survey (GPS) is one of the five near infrared Public Legacy Surveys that are being undertaken by the UKIDSS consortium, using the Wide Field Camera on the United Kingdom Infrared Telescope. It is surveying 1868 sq.deg. of the northern and equatorial Galactic plane at Galactic latitudes -5

  8. Optimization of starshades: focal plane versus pupil plane

    CERN Document Server

    Flamary, Rémi

    2014-01-01

    We search for the best possible transmission for an external occulter coronagraph that is dedicated to the direct observation of terrestrial exoplanets. We show that better observation conditions are obtained when the flux in the focal plane is minimized in the zone in which the exoplanet is observed, instead of the total flux received by the telescope. We describe the transmission of the occulter as a sum of basis functions. For each element of the basis, we numerically computed the Fresnel diffraction at the aperture of the telescope and the complex amplitude at its focus. The basis functions are circular disks that are linearly apodized over a few centimeters (truncated cones). We complemented the numerical calculation of the Fresnel diffraction for these functions by a comparison with pure circular discs (cylinder) for which an analytical expression, based on a decomposition in Lommel series, is available. The technique of deriving the optimal transmission for a given spectral bandwidth is a classical reg...

  9. Counting plane curves of any genus

    OpenAIRE

    Caporaso, Lucia; Harris, Joe

    1996-01-01

    We obtain a recursive formula answering the following question: How many irreducible, plane curves of degree d and (geometric) genus g pass through 3d-1+g general points in the plane? The formula is proved by studying suitable degenerations of plane curves.

  10. The characteristic numbers of quartic plane curves

    OpenAIRE

    Vakil, Ravi

    1998-01-01

    The characteristic numbers of smooth plane quartics are computed using intersection theory on a component of the moduli space of stable maps. This completes the verification of Zeuthen's prediction of characteristic numbers of smooth plane curves. A short sketch of a computation of the characteristic numbers of plane cubics is also given as an illustration.

  11. Monopole Antenna with Modify Ground Plane

    OpenAIRE

    kamal raj singh rajoriya; Singhal, P.K.

    2012-01-01

    This paper presents on modified the ground plane of monopole antenna with varying the shape and length. Basically the length of ground plane of monopole antenna is equal and greater than λ/4. Here analyzed a different ground plane of monopole antenna that is provided an efficient bandwidth with sufficient return loss.

  12. Monopole Antenna with Modify Ground Plane

    Directory of Open Access Journals (Sweden)

    kamal raj singh rajoriya

    2012-06-01

    Full Text Available This paper presents on modified the ground plane of monopole antenna with varying the shape and length. Basically the length of ground plane of monopole antenna is equal and greater than λ/4. Here analyzed a different ground plane of monopole antenna that is provided an efficient bandwidth with sufficient return loss.

  13. An international review of the frequency of single-bicycle crashes (SBCs) and their relation to bicycle modal share

    DEFF Research Database (Denmark)

    Schepers, Paul; Agerholm, Niels; Amoros, Emmanuelle; Benington, Rob; Bjørnskau, Torkel; Dhondt, Stijn; de Geus, Bas; Hagemeister, Carmen; Loo, Becky P. Y.; Niska, Anna

    2015-01-01

    Objectives To study cyclists’ share of transport modes (modal share) and single-bicycle crashes (SBCs) in different countries in order to investigate if the proportion of cyclist injuries resulting from SBCs is affected by variation in modal share. Methods A literature search identified figures...... SBC casualties among the total number of road crash casualties increases proportionally less than the increase in bicycle modal share. Conclusions While most fatal injuries among cyclists are due to motor vehicle–bicycle crashes, most hospital admissions and emergency department attendances result...

  14. Development and use of computational techniques in Army Aviation research and development programs for crash resistant helicopter technology

    Science.gov (United States)

    Burrows, Leroy T.

    1993-08-01

    During the 1960's over 30 full-scale aircraft crash tests were conducted by the Flight Safety Foundation under contract to the Aviation Applied Technology Directorate (AATD) of the U.S. Army Aviation Systems Command (AVSCOM). The purpose of these tests were to conduct crash injury investigations that would provide a basis for the formulation of sound crash resistance design criteria for light fixed-wing and rotary wing aircraft. This resulted in the Crash Survival Design Criteria Designer's Guide which was first published in 1967 and has been revised numerous times, the last being in 1989. Full-scale aircraft crash testing is an expensive way to investigate structural deformations of occupied spaces and to determine the decelerative loadings experienced by occupants in a crash. This gave initial impetus to the U.S. Army to develop analytical methods to predict the dynamic response of aircraft structures in a crash. It was believed that such analytical tools could be very useful in the preliminary design stage of a new helicopter system which is required to demonstrate a level of crash resistance and had to be more cost effective than full-scale crash tests or numerous component design support tests. From an economic point of view, it is more efficient to optimize for the incorporation of crash resistance features early in the design stage. However, during preliminary design it is doubtful if sufficient design details, which influence the exact plastic deformation shape of structural elements, will be available. The availability of simple procedures to predict energy absorption and load-deformation characteristics will allow the designer to initiate valuable cost, weight, and geometry tradeoff studies. The development of these procedures will require some testing of typical specimens. This testing should, as a minimum, verify the validity of proposed procedures for providing pertinent nonlinear load-deformation data. It was hoped that through the use of these

  15. Occupant Dynamics in Rollover Crashes: Influence of Roof Deformation and Seat Belt Performance on Probable Spinal Column Injury

    OpenAIRE

    Bidez, Martha W.; Cochran, John E.; King, Dottie; Burke, Donald S.

    2007-01-01

    Motor vehicle crashes are the leading cause of death in the United States for people ages 3–33, and rollover crashes have a higher fatality rate than any other crash mode. At the request and under the sponsorship of Ford Motor Company, Autoliv conducted a series of dynamic rollover tests on Ford Explorer sport utility vehicles (SUV) during 1998 and 1999. Data from those tests were made available to the public and were analyzed in this study to investigate the magnitude of and the temporal rel...

  16. An introduction to finite projective planes

    CERN Document Server

    Albert, Abraham Adrian

    2015-01-01

    Geared toward both beginning and advanced undergraduate and graduate students, this self-contained treatment offers an elementary approach to finite projective planes. Following a review of the basics of projective geometry, the text examines finite planes, field planes, and coordinates in an arbitrary plane. Additional topics include central collineations and the little Desargues' property, the fundamental theorem, and examples of finite non-Desarguesian planes.Virtually no knowledge or sophistication on the part of the student is assumed, and every algebraic system that arises is defined and

  17. The Development of Two Composite Energy Absorbers for Use in a Transport Rotorcraft Airframe Crash Testbed (TRACT 2) Full-Scale Crash Test

    Science.gov (United States)

    Littell, Justin D.; Jackson, Karen E.; Annett, Martin S.; Seal, Michael D.; Fasanella, Edwin L.

    2015-01-01

    Two composite energy absorbers were developed and evaluated at NASA Langley Research Center through multi-level testing and simulation performed under the Transport Rotorcraft Airframe Crash Testbed (TRACT) research program. A conical-shaped energy absorber, designated the conusoid, was evaluated that consisted of four layers of hybrid carbon-Kevlar plain weave fabric oriented at [+45deg/-45deg/-45deg/+45deg] with respect to the vertical direction. A sinusoidal-shaped energy absorber, designated the sinusoid, was developed that consisted of hybrid carbon-Kevlar plain weave fabric face sheets, two layers for each face sheet oriented at +/-45deg with respect to the vertical direction, and a closed-cell ELFOAM P200 polyisocyanurate (2.0-lb/cu ft) foam core. The design goal for the energy absorbers was to achieve average floor-level accelerations of between 25- and 40-g during the full-scale crash test of a retrofitted CH-46E helicopter airframe, designated TRACT 2. Variations in both designs were assessed through dynamic crush testing of component specimens. Once the designs were finalized, subfloor beams of each configuration were fabricated and retrofitted into a barrel section of a CH-46E helicopter. A vertical drop test of the barrel section was conducted onto concrete to evaluate the performance of the energy absorbers prior to retrofit into TRACT 2. The retrofitted airframe was crash tested under combined forward and vertical velocity conditions onto soft soil. Finite element models were developed of all test articles and simulations were performed using LS-DYNA, a commercial nonlinear explicit transient dynamic finite element code. Test-analysis results are presented for each energy absorber as comparisons of time-history responses, as well as predicted and experimental structural deformations and progressive damage under impact loading for each evaluation level.

  18. Topological equivalence of finitely determined real analytic plane-to-plane map-germs

    OpenAIRE

    Skutlaberg, Olav

    2009-01-01

    Generic smooth plane-to-plane map germs are topologically equivalent to cones of mappings of the circle. We carry out a complete topological classification of smooth stable mappings of the circle and show how this classification leads, via the result mentioned above, to a topological classification of finitely determined real analytic plane-to-plane map germs.

  19. Ion heating and current and momentum profile relaxation during sawtooth crashes in the MST reversed field pinch

    International Nuclear Information System (INIS)

    Robust and global phenomena associated with sawtooth crashes are studied in a reversed field pinch plasma. These phenomena are: current profile relaxation, plasma momentum profile relaxation, and anomalous ion heating. We have implemented new diagnostics to characterize these processes with good spatial and temporal resolution. The profile of the parallel current to the magnetic field (inferred via laser polarimetry) flattens after the sawtooth crash which provides the most complete evidence of plasma relaxation toward a Taylor state. At the sawtooth crash we observe transport and relaxation of both the toroidal and parallel plasma momentum. The flattening of the parallel momentum profile has been predicted by two-fluid MHD theory. The majority ion temperature is measured with the Rutherford scattering diagnostic and the minority ion temperature is measured with charge exchange recombination spectroscopy. At the sawtooth crash the ion temperature almost doubles and a significant fraction of the equilibrium magnetic field energy is transferred into the ion thermal energy. (author)

  20. Assessment of the consequences of aircraft crashes on a PWR power plant (as applied to Sizewell B)

    International Nuclear Information System (INIS)

    The study analyses the probability of severe core damage and an uncontrolled release of radioactivity in the event of a postulated crash of a military combat aircraft on the central buildings of the proposed Sizewell-B pressurized water reactor. The study identifies a number of regional damage states which would arise as the result of such a crash. The probabilities of damage states are estimated on the basis of building geometries and resistance to impacts and the distribution of aircraft crash energies and angles in the vicinity of the site. For each regional damage state the surviving equipment is compared with the minimum requirements for reactor core control and from this comparison, probabilities of core damage are estimated using simple functional event trees. It is concluded that it is unreasonably pessimistic to assume that an aircraft crash onto Sizewell-B would lead inevitably to a core meltdown or uncontrolled release of radioactivity. (U.K.)

  1. Type, size and age of vehicles driven by teenage drivers killed in crashes during 2008-2012.

    Science.gov (United States)

    McCartt, Anne T; Teoh, Eric R

    2015-04-01

    Given teenagers' elevated crash rates, it is especially important that their vehicles have key safety features and good crash protection. A profile of vehicles driven by teenagers killed in crashes was developed. Data on vehicles of drivers ages 15-17 and ages 35-50 who died in crashes during 2008-2012 were obtained from the Fatality Analysis Reporting System. Using vehicle identification numbers, the vehicle make, model and model year were identified. 29% of fatally injured teenagers were driving mini or small cars, 82% were driving vehicles at least 6 years old, and 48% were driving vehicles at least 11 years old. Compared with middle-aged drivers, teenagers' vehicles more often were small or mini cars or older vehicles. Few teenagers' vehicles had electronic stability control or side airbags as standard features. Parents should consider safety when choosing vehicles for their teenagers. PMID:25525130

  2. Mathematical modeling and parameters estimation of car crash using eigensystem realization algorithm and curve-fitting approaches

    OpenAIRE

    Munyazikwiye, Bernard B.; Karimi, Hamid Reza; Robbersmyr, Kjell G.

    2013-01-01

    An eigensystem realization algorithm (ERA) approach for estimating the structural system matrices is proposed in this paper using the measurements of acceleration data available from the real crash test. A mathematical model that represents the real vehicle frontal crash scenario is presented. The model's structure is a double-spring-mass-damper system, whereby the front mass represents the vehicle-chassis and the rear mass represents the passenger compartment. The physical parameters of the ...

  3. Mathematical Modeling and Parameters Estimation of Car Crash Using Eigensystem Realization Algorithm and Curve-Fitting Approaches

    OpenAIRE

    Munyazikwiye, Bernard B.; Karimi, Hamid Reza; Robbersmyr, Kjell Gunnar

    2013-01-01

    An eigensystem realization algorithm (ERA) approach for estimating the structural system matrices is proposed in this paper using the measurements of acceleration data available from the real crash test. A mathematical model that represents the real vehicle frontal crash scenario is presented. The model’s structure is a double-spring-mass-damper system, whereby the front mass represents the vehicle-chassis and the rear mass represents the passenger compartment. The physical parameters of the ...

  4. Crash-Induced Vibration and Safety Assessment of Breakaway-Type Post Structures Made of High Anticorrosion Steels

    OpenAIRE

    Lee, Sang-Youl

    2016-01-01

    This study deals with car crash effects and passenger safety assessment of post structures with breakaway types using high performance steel materials. To disperse the impact force when a car crashes into a post, the post could be designed with a breakaway feature. In this study, we used a new high anticorrosion steel for the development of advanced breakaways. Based on the improved Cowper-Symonds model, specific physical properties to the high anticorrosion steel were determined. In particul...

  5. Studying the effect of weather conditions on daily crash counts using a discrete time-series model

    OpenAIRE

    Brijs, Tom; Karlis, Dimitris; Wets, Geert

    2008-01-01

    In previous research, significant effects of weather conditions on car crashes have been found. However, most studies use monthly or yearly data and only few studies are available analyzing the impact of weather conditions on daily car crash counts. Furthermore, the studies that are available on a daily level do not explicitly model the data in a time-series context, hereby ignoring the temporal serial correlation that may be present in the data. In this paper, we introduce an integer autoreg...

  6. Use and Limitations of Crash Data in Determining the Priority For Treating Sites with Low Skid Resistance

    OpenAIRE

    VINER, Helen; Coyle, Fiona; Brittain, S.; Caudwell, L.

    2012-01-01

    In assessing the treatment of sites with low skid resistance, the relative priority of lengths marginally below skid resistance threshold where there have been a number of recent crashes must be balanced with that of lengths substantially below the threshold with no recent crash history. The judgment is complicated by the highway authority having a duty of care to maintain the road in a safe and serviceable condition, so it is not acceptable to let the skid resistance deteriorate indefinitely...

  7. Safety impacts of platform tram stops on pedestrians in mixed traffic operation: A comparison group before-after crash study.

    Science.gov (United States)

    Naznin, Farhana; Currie, Graham; Logan, David; Sarvi, Majid

    2016-01-01

    Tram stops in mixed traffic environments present a variety of safety, accessibility and transport efficiency challenges. In Melbourne, Australia the hundred year-old electric tram system is progressively being modernized to improve passenger accessibility. Platform stops, incorporating raised platforms for level entry into low floor trams, are being retro-fitted system-wide to replace older design stops. The aim of this study was to investigate the safety impacts of platform stops over older design stops (i.e. Melbourne safety zone tram stops) on pedestrians in the context of mixed traffic tram operation in Melbourne, using an advanced before-after crash analysis approach, the comparison group (CG) method. The CG method evaluates safety impacts by taking into account the general trends in safety and the unobserved factors at treatment and comparison sites that can alter the outcomes of a simple before-after analysis. The results showed that pedestrian-involved all injury crashes reduced by 43% after platform stop installation. This paper also explores a concern that the conventional CG method might underestimate safety impacts as a result of large differences in passenger stop use between treatment and comparison sites, suggesting differences in crash risk exposure. To adjust for this, a modified analysis explored crash rates (crash counts per 10,000 stop passengers) for each site. The adjusted results suggested greater reductions in pedestrian-involved crashes after platform stop installation: an 81% reduction in pedestrian-involved all injury crashes and 86% reduction in pedestrian-involved FSI crashes, both are significant at the 95% level. Overall, the results suggest that platform stops have considerable safety benefits for pedestrians. Implications for policy and areas for future research are explored. PMID:26476596

  8. Road traffic crash circumstances and consequences among young unlicensed drivers: A Swedish cohort study on socioeconomic disparities

    Directory of Open Access Journals (Sweden)

    Laflamme Lucie

    2010-01-01

    Full Text Available Abstract Background Young car drivers run a higher risk of road traffic crash and injury not only because of their lack of experience but also because of their young age and their greater propensity for adopting unsafe driving practices. Also, low family socioeconomic position increases the risk of crash and of severe crash in particular. Whether this holds true for young unlicensed drivers as well is not known. Increasing attention is being drawn to the prevalence and practice of unlicensed driving among young people as an important contributor to road traffic fatalities. Methods This is a population-based cohort study linking Swedish national register data for a cohort of 1 616 621 individuals born between 1977 and 1991. Crash circumstances for first-time road traffic crash (RTC were compared considering licensed and unlicensed drivers. The socioeconomic distribution of injury was assessed considering household socioeconomic position, social welfare benefits, and level of urbanicity of the living area. The main outcome measure is relative risk of RTC. Results RTCs involving unlicensed drivers were over-represented among male drivers, suspected impaired drivers, severe injuries, crashes occurring in higher speed limit areas, and in fair road conditions. Unlicensed drivers from families in a lower socioeconomic position showed increased relative risks for RTC in the range of 1.75 to 3.25. Those living in rural areas had an increased relative risk for a severe RTC of 3.29 (95% CI 2.47 - 4.39 compared to those living in metropolitan areas. Conclusions At the time of the crash, young unlicensed drivers display more risky driving practices than their licensed counterparts. Just as licensed drivers, unlicensed young people from low socioeconomic positions are over-represented in the most severe injury crashes. Whether the mechanisms lying behind those similarities compare between these groups remains to be determined.

  9. Motor vehicle crashes in diabetic patients with tight glycemic control: a population-based case control analysis.

    Directory of Open Access Journals (Sweden)

    Donald A Redelmeier

    2009-12-01

    Full Text Available BACKGROUND: Complications from diabetes mellitus can compromise a driver's ability to safely operate a motor vehicle, yet little is known about whether euglycemia predicts normal driving risks among adults with diabetes. We studied the association between glycosylated hemoglobin (HbA1c and the risk of a motor vehicle crash using a population-based case control analysis. METHODS AND FINDINGS: We identified consecutive drivers reported to vehicle licensing authorities between January 1, 2005 to January 1, 2007 who had a diagnosis of diabetes mellitus and a HbA1c documented. The risk of a crash was calculated taking into account potential confounders including blood glucose monitoring, complications, and treatments. A total of 57 patients were involved in a crash and 738 were not involved in a crash. The mean HbA1c was lower for those in a crash than controls (7.4% versus 7.9%, unpaired t-test, p = 0.019, equal to a 26% increase in the relative risk of a crash for each 1% reduction in HbA1c (odds ratio = 1.26, 95% confidence interval 1.03-1.54. The trend was evident across the range of HbA1c values and persisted after adjustment for measured confounders (odds ratio = 1.25, 95% confidence interval 1.02-1.55. The two other significant risk factors for a crash were a history of severe hypoglycemia requiring outside assistance (odds ratio = 4.07, 95% confidence interval 2.35-7.04 and later age at diabetes diagnosis (odds ratio per decade = 1.29, 95% confidence interval 1.07-1.57. CONCLUSIONS: In this selected population, tighter glycemic control, as measured by the HbA1c, is associated with an increased risk of a motor vehicle crash.

  10. The log-periodic-AR(1)-GARCH(1,1) model for financial crashes

    CERN Document Server

    Gazola, L; Pizzinga, A; Riera, R

    2008-01-01

    This paper intends to meet recent claims for the attainment of more rigorous statistical methodology within the econophysics literature. To this end, we consider an econometric approach to investigate the outcomes of the log-periodic model of price movements, which has been largely used to forecast financial crashes. In order to accomplish reliable statistical inference for unknown parameters, we incorporate an autoregressive dynamic and a conditional heteroskedasticity structure in the error term of the original model, yielding the log-periodic-AR(1)-GARCH(1,1) model. Both the original and the extended models are fitted to financial indices of U. S. market, namely S&P500 and NASDAQ. Our analysis reveal two main points: (i) the log-periodic-AR(1)-GARCH(1,1) model has residuals with better statistical properties and (ii) the estimation of the parameter concerning the time of the financial crash has been improved.

  11. Automated dimensional inspection of cars in crash tests with digital photogrammetry

    Science.gov (United States)

    Beyer, Horst A.

    1991-09-01

    Changes in the shape of cars due to impact in crash tests are determined from the deformation vectors of points located in specific positions on the car. The coordinates of these points are measured before as well as after the test. Costs and measurement time can be significantly reduced by automated dimensional inspection with digital photogrammetry. This paper reports on a pilot test in which the measurement of a car prepared for a crash test was performed under practical conditions. It was shown that an accuracy of 1 mm in each coordinate axis within a measurement volume of 5 X 2 X 2 m3 can be achieved under factory- floor conditions with low-cost CCD cameras. A high level of automation and robustness was demonstrated. The measurements were performed in a very short time with model-driven techniques.

  12. Analyzing the Relationship Between Car Generation and Severity of Motor-Vehicle Crashes in Denmark

    DEFF Research Database (Denmark)

    Rich, Jeppe; Prato, Carlo Giacomo; Hels, Tove;

    2013-01-01

    car market with remarkably high registration tax that causes potential buyers to hold longer onto old cars, the relationship between technological enhancements of vehicles and severity of crashes requires particular attention. The current study investigated the relationship between car generation (i.......e., car’s first registration year) and injury severity sustained by car drivers involved in accidents in Denmark between 2004 and 2010. A generalized ordered logit model was estimated while controlling for several characteristics of the crash, the vehicle and the persons involved, and a sensitivity...... analysis was performed to assess the effect of car generation on drivers’ injury severity. Results illustrate that newer car generations are associated to significantly lower probability of injury and fatality, and that replacing older cars with newer ones introduces significant and not to be overlooked...

  13. Spatiotemporal and random parameter panel data models of traffic crash fatalities in Vietnam.

    Science.gov (United States)

    Truong, Long T; Kieu, Le-Minh; Vu, Tuan A

    2016-09-01

    This paper investigates factors associated with traffic crash fatalities in 63 provinces of Vietnam during the period from 2012 to 2014. Random effect negative binomial (RENB) and random parameter negative binomial (RPNB) panel data models are adopted to consider spatial heterogeneity across provinces. In addition, a spatiotemporal model with conditional autoregressive priors (ST-CAR) is utilised to account for spatiotemporal autocorrelation in the data. The statistical comparison indicates the ST-CAR model outperforms the RENB and RPNB models. Estimation results provide several significant findings. For example, traffic crash fatalities tend to be higher in provinces with greater numbers of level crossings. Passenger distance travelled and road lengths are also positively associated with fatalities. However, hospital densities are negatively associated with fatalities. The safety impact of the national highway 1A, the main transport corridor of the country, is also highlighted. PMID:27294863

  14. Effectiveness of low speed autonomous emergency braking in real-world rear-end crashes.

    Science.gov (United States)

    Fildes, B; Keall, M; Bos, N; Lie, A; Page, Y; Pastor, C; Pennisi, L; Rizzi, M; Thomas, P; Tingvall, C

    2015-08-01

    This study set out to evaluate the effectiveness of low speed autonomous emergency braking (AEB) technology in current model passenger vehicles, based on real-world crash experience. The validating vehicle safety through meta-analysis (VVSMA) group comprising a collaboration of government, industry consumer organisations and researchers, pooled data from a number of countries using a standard analysis format and the established MUND approach. Induced exposure methods were adopted to control for any extraneous effects. The findings showed a 38 percent overall reduction in rear-end crashes for vehicles fitted with AEB compared to a comparison sample of similar vehicles. There was no statistical evidence of any difference in effect between urban (≤60 km/h) and rural (>60 km/h) speed zones. Areas requiring further research were identified and widespread fitment through the vehicle fleet is recommended. PMID:25935427

  15. Design of the Cross Section Shape of AN Aluminum Crash Box for Crashworthiness Enhancement of a CAR

    Science.gov (United States)

    Kim, S. B.; Huh, H.; Lee, G. H.; Yoo, J. S.; Lee, M. Y.

    This paper deals with the crashworthiness of an aluminum crash box for an auto-body with the various shapes of cross section such as a rectangle, a hexagon and an octagon. First, crash boxes with various cross sections were tested with numerical simulation to obtain the energy absorption capacity and the mean load. In case of the simple axial crush, the octagon shape shows higher mean load and energy absorption than the other two shapes. Secondly, the crash boxes were assembled to a simplified auto-body model for the overall crashworthiness. The model consists of a bumper, crash boxes, front side members and a sub-frame representing the behavior of a full car at the low speed impact. The analysis result shows that the rectangular cross section shows the best performance as a crash box which deforms prior to the front side member. The hexagonal and octagonal cross sections undergo torsion and local buckling as the width of cross section decreases while the rectangular cross section does not. The simulation result of the rectangular crash box was verified with the experimental result. The simulation result shows close tendency in the deformed shape and the load-displacement curve to the experimental result.

  16. Exploring the impacts of safety culture on immigrants' vulnerability in non-motorized crashes: a cross-sectional study.

    Science.gov (United States)

    Chen, Cynthia; Lin, Haiyun; Loo, Becky P Y

    2012-02-01

    Pedestrians and cyclists are a vulnerable group of road users. Immigrants are disproportionally represented in pedestrian and cyclist crashes. We postulate that the mismatch in safety culture between countries of their origin and the U.S.A. contribute to their vulnerability in pedestrian and cyclist crashes. Over time, the differences may disappear and immigrants' traffic behavior gravitates toward those of native-borns. We describe this process as safety assimilation. Using the pedestrian and cyclist crash database in New York City between 2001 and 2003, we examined the effects of foreign-born population, their countries of origin, and time of entry into the USA on census tract-level pedestrian and cyclist crashes. We find that neighborhoods with a higher concentration of immigrants, especially those from Latin America, Eastern Europe, and Asia, have more crashes. Our results also exhibit a pattern of the hypothesized safety assimilation process. The study suggests a higher level of vulnerability of immigrants to pedestrian and cyclist crashes. We propose that targeted policies and programs need to be developed for immigrants of different countries of origin. PMID:22173474

  17. Estimate of aircraft crash hit frequencies on to facilities at the Lawrence Livermore National Laboratory (LLNL) Site 200

    International Nuclear Information System (INIS)

    Department of Energy (DOE) nuclear facilities are required by DOE Order 5480.23, Section 8.b.(3)(k) to consider external events as initiating events to accidents within the scope of their Safety Analysis Reports (SAR). One of the external initiating events which should be considered within the scope of a SAR is an aircraft accident, i.e., an aircraft crashing into the nuclear facility with the related impact and fire leading to penetration of the facility and to the release of radioactive and/or hazardous materials. This report presents the results of an Aircraft Crash Frequency analysis performed for the Materials Management Area (MMA), and the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) Site 200. The analysis estimates only the aircraft crash hit frequency on to the analyzed facilities. No initial aircraft crash hit frequency screening structural response calculations of the facilities to the aircraft impact, or consequence analysis of radioactive/hazardous materials released following the aircraft impact are performed. The method used to estimate the aircraft crash hit frequencies on to facilities at the Lawrence Livermore National Laboratory (LLNL) generally follows the procedure given by the DOE Standard 3014-96 on Aircraft Crash Analysis. However, certain adjustments were made to the DOE Standard procedure because of the site specific fight environment or because of facility specific characteristics

  18. Modeling the effects of AADT on predicting multiple-vehicle crashes at urban and suburban signalized intersections.

    Science.gov (United States)

    Chen, Chen; Xie, Yuanchang

    2016-06-01

    Annual Average Daily Traffic (AADT) is often considered as a main covariate for predicting crash frequencies at urban and suburban intersections. A linear functional form is typically assumed for the Safety Performance Function (SPF) to describe the relationship between the natural logarithm of expected crash frequency and covariates derived from AADTs. Such a linearity assumption has been questioned by many researchers. This study applies Generalized Additive Models (GAMs) and Piecewise Linear Negative Binomial (PLNB) regression models to fit intersection crash data. Various covariates derived from minor-and major-approach AADTs are considered. Three different dependent variables are modeled, which are total multiple-vehicle crashes, rear-end crashes, and angle crashes. The modeling results suggest that a nonlinear functional form may be more appropriate. Also, the results show that it is important to take into consideration the joint safety effects of multiple covariates. Additionally, it is found that the ratio of minor to major-approach AADT has a varying impact on intersection safety and deserves further investigations. PMID:26974024

  19. The Nexus between Analyst Forecast Dispersion and Expected Returns Surrounding Stock Market Crashes

    Directory of Open Access Journals (Sweden)

    Terence Tai-Leung Chong

    2009-12-01

    Full Text Available The performance of analysts’ forecasts has attracted increasing attention in recent years. However, as yet, no empirical study has investigated the nexus between the analyst forecast dispersion (AFD and excess returns surrounding stock market crashes in any depth. This paper attempts to fill this void by estimating a Fama-French model regression with AFD as a factor. Instead of an expected linear relationship, a nonlinear U-shape relationship between the AFD and excess returns is found.

  20. Market Reaction to Acquisition Announcements after the 2008 Stock Market Crash

    OpenAIRE

    Ozge Uyger; Gulser Meric; Ilhan Meric,

    2014-01-01

    Market reaction to mergers and acquisitions is a popular research topic in finance. It has been well documented in empirical literature that target companies earn significant abnormal market returns in corporate acquisitions. However, the effects of stock market crashes, and the effects of whether the acquirer is a domestic firm or a foreign firm, on target firm abnormal returns have not been studied sufficiently. In this paper, we make a contribution to the extant literature on these subject...

  1. Factors influencing social and health outcomes after motor vehicle crash injury: an inception cohort study protocol

    OpenAIRE

    Jagnoor, Jagnoor; Blyth, Fiona; Gabbe, Belinda; Derrett, Sarah; Boufous, Soufiane; Dinh, Michael; Day, Robert; Button, Gregory; Gillett, Mark; Joseph, Tony; Nicholas, Michael; Ivers, Rebecca; Maher, Chris G.; Willcock, Simon; Kenardy, Justin

    2014-01-01

    Background There is growing evidence that health and social outcomes following motor vehicle crash injury are related to cognitive and emotional responses of the injured individual, as well as relationships between the injured individual and the compensation systems with which they interact. As most of this evidence comes from other states in Australia or overseas, investigation is therefore warranted to identify the key determinants of health and social outcomes following injury in the conte...

  2. General and specific statistical properties of foreign exchange markets during a financial crash

    Science.gov (United States)

    Li, Wei-Shen; Tsai, Yun-Jie; Shen, Yu-Hsien; Liaw, Sy-Sang

    2016-06-01

    We investigate minute-by-minute foreign exchange rate (FX) data of 14 currencies with different exchange-rate regimes during a financial crash, and divide these data into several stages according to their respective tendencies: depreciation stage (stage 1), fluctuating stage (stage 2), and appreciation stage (stage 3). The tail distribution of FX rate returns satisfies a power-law structure for different types of currencies. We find the absolute value of the power-law exponent is smaller in emerging markets than in developed markets, especially during the stage 1, and is greatest in pegged currencies. We also find that the correlation properties of the FX rate return series have quite disparate results among the various types of currencies. Currencies in developed markets respectively have weak persistence and anti-persistence in short and long timescales; whereas the pegged currencies and currencies in emerging markets show different degrees of anti-persistence in various timescales. Further analyses on the data in divided stages indicate that emerging markets and pegged currencies have more prominent dual fractal structures after the depreciation stage, while the developed markets do not. Hurst exponent analyses on the sign series yield similar results to that on the original return series for most currencies. The magnitude series of the returns provide some unique results during a crash. The developed market currencies have strong persistence and exhibit a weaker correlation in the depreciation and appreciation stages. In contrast, the currencies of emerging markets as well as pegged currencies fail to show such a transformation, but rather show a constant-correlation behavior in the corresponding stages of a crash. These results indicate that external shocks exert different degrees of influence during different stages of the crash in various markets.

  3. 'Crashing' the rugby scrum -- an avoidable cause of cervical spinal injury. Case reports.

    Science.gov (United States)

    Scher, A T

    1982-06-12

    Deliberate crashing of the opposing packs prior to a rugby scrum is an illegal but commonly practised manoeuvre which can lead to abnormal flexion forces being applied to players in the front row, with resultant cervical spine and spinal cord injury. Two cases of cervical spinal cord injury sustained in this manner are presented. The mechanism of injury, the forces involved and preventive measures are discussed. PMID:7089756

  4. Requirements modeling in SEAM: The example of a car crash management system

    OpenAIRE

    Wegmann, Alain; Bajic-Bizumic, Biljana; Golnam, Arash; Popescu, George; Tapandjieva, Gorica; Saxena, Anshuman Bahadur; Yassaee, Maedeh; Regev, Gil

    2013-01-01

    This paper presents how business and IT requirements are captured with the Systemic Enterprise Architecture Methodology (SEAM). The method is applied to the Car Crash Management System (CMS) - Software Product Line (SPL) case study. The existing business situation is analyzed. We identify the problems and list relevant solutions. We select one of these solutions for which we define the business and the IT requirements. We then present the two components of SEAM used in this paper, goal-belief...

  5. How to Decrease Pedestrian Injuries: Conceptual Evolutions Starting From 137 Crash Tests

    OpenAIRE

    Thollon, L.; Jammes, C.; Behr, M.; ARNOUX,PJ; Cavallero, C.; Brunet, C

    2007-01-01

    The improvement of vulnerable users' protection has become an essential objective for our society. Injury assessments observed in clinical traumatology have led researchers and manufacturers to understand the mechanisms involved and to design safe vehicles to reduce the severity of pedestrian injuries. In all, 137 crash tests between 1979 and 2004 with postmortal human subjects (PMHS) were performed at the Laboratory of Applied Biomechanics to access pedestrian protection. A retrospective ana...

  6. Realizing stock market crashes: stochastic cusp catastrophe model of returns under time-varying volatility

    Czech Academy of Sciences Publication Activity Database

    Baruník, Jozef; Kukačka, Jiří

    2015-01-01

    Roč. 15, č. 6 (2015), s. 959-973. ISSN 1469-7688 R&D Projects: GA ČR GA402/09/0965; GA ČR GA13-32263S EU Projects: European Commission 612955 - FINMAP Institutional support: RVO:67985556 Keywords : Stochastic cusp catastrophe model * Realized volatility * Bifurcations * Stock market crash Subject RIV: AH - Economics Impact factor: 0.653, year: 2014 http://library.utia.cas.cz/separaty/2014/E/barunik-0434202.pdf

  7. Matching or Crashing? Personality-based Team Formation in Crowdsourcing Environments

    OpenAIRE

    Lykourentzou, Ioanna; Antoniou, Angeliki; Naudet, Yannick

    2015-01-01

    "Does placing workers together based on their personality give better performance results in cooperative crowdsourcing settings, compared to non-personality based crowd team formation?" In this work we examine the impact of personality compatibility on the effectiveness of crowdsourced team work. Using a personality-based group dynamics approach, we examine two main types of personality combinations (matching and crashing) on two main types of tasks (collaborative and competitive). Our experi...

  8. The Crash of 1882 and the Bailout of the Paris Bourse

    OpenAIRE

    Eugene N. White

    2007-01-01

    The crash of the French stock market in 1882 presented the Paris Bourse with its worst crisis of the nineteenth century. Its structure was similar in key respects to today’s futures markets, with a dominant forward market leading the Bourse to adopt a common fund to guarantee transactions and liquidity. While this mutualization of risk protects clients and brokers from idiosyncratic shocks, it is generally assumed that it also provides considerable protection against systemic shocks, as no tw...

  9. A UNIT BASED CRASHING PERT NETWORK FOR OPTIMIZATION OF SOFTWARE PROJECT COST

    OpenAIRE

    PRITI SINGH; FLORENTIN SMARANDACHE; DIPTI CHAUHAN; AMIT BHAGHEL

    2014-01-01

    Crashing is a process of expediting project schedule by compressing the total project duration. It is helpful when managers want to avoid incoming bad weather season. However, the downside is that more resources are needed to speed-up a part of a project, even if resources may be withdrawn from one facet of the project and used to speed-up the section that is lagging behind.

  10. Aircraft-crash-protected steel reactor building roof structure for the European market

    International Nuclear Information System (INIS)

    This paper recommends the use of all steel roof structures for the reactor building of European Boiling Water Reactor (BWR) plants. This change would make the advanced US BWR designs more compatible with European requirements. Replacement of the existing concrete roof slab with a sufficiently thick steel plate would eliminate the concrete spelling resulting from a postulated aircraft crash, potentially damaging the drywell head or the spent fuel pool

  11. Safe Routes to Play? Pedestrian and Bicyclist Crashes Near Parks in the Los Angeles Region

    OpenAIRE

    Hanning, Cooper; Jerrett, Michael; Su, Jason G.; Wolch, Jennifer

    2012-01-01

    Rationale: Areas near parks may present active travelers with higher risks than in other areas due to the confluence of more pedestrians and bicyclists, younger travelers, and the potential for increased numbers of motor vehicles. These risks may be amplified in low-income and minority neighborhoods due to generally higher rates of walking or lack of safety infrastructure.  Objectives: We pursued three research objectives: (1) to determine if pedestrian and bicycle crashes occur at h...

  12. CDC Vital Signs–Motor Vehicle Crash Deaths

    Centers for Disease Control (CDC) Podcasts

    2016-07-06

    This podcast is based on the July 2016 CDC Vital Signs report. In the U.S., about 90 people die in motor vehicle crashes each day and thousands more are injured, resulting in hundreds of millions of dollars in direct medical costs each year. Learn what you can do to stay safe.  Created: 7/6/2016 by National Center for Injury Prevention and Control (NCIPC).   Date Released: 7/6/2016.

  13. Sport cycling crashes on public roads, the influence of bunch riding and experience.

    OpenAIRE

    Wijlhuizen, G.J. & Gent, P. van

    2014-01-01

    Cycling is a popular but unsafe mode of transport in the Netherlands and the number of seriously injured bicyclists has increased significantly since 2006. A special subgroup is the population of sport cyclists who perform their sport on public roads. The number of road crashes with sport cyclists shows an increasing trend. The authors propose two factors which might contribute to this trend. First, bunch riding among sport cyclists, and second the inflow of cyclists with low experience. No e...

  14. Modelling physiological features of Human body behavior in car crash simulations

    OpenAIRE

    Behr, M.; GODIO,Y; LLARI,M; Brunet, C

    2007-01-01

    Human numerical models are widely used to investigate injury mechanisms involved in car crash configurations. One limitation of these models is linked to the time dependency of biological tissues mechanical properties, as a result of various physiological modifications. To answer this limitation, we present one possible approach to evaluate the influence of internal body pressures (mainly resulting from breathing) on the result of a frontal impact, by modelling main muscles responsible for re...

  15. Evaluation of damages of airplane crash in European Advanced Boiling Water Reactor (EU-ABWR)

    International Nuclear Information System (INIS)

    European Advanced Boiling Water Reactor (EU-ABWR) is developed by Toshiba. EU-ABWR accommodates an armored reactor building against Airplane Crash (APC), severe accident mitigation systems, N+2 principle in safety systems and a large output of 1600 MWe. Thanks to above mentioned features, EU-ABWR's design objectives and principles are consistent with safety requirements in an European market. In this paper, evaluation of damages induced by APC has been summarized. (author)

  16. The invisible hand and the rational agent are behind bubbles and crashes

    OpenAIRE

    Galam, Serge

    2016-01-01

    The substantial turmoil created by both 2000 dot-com crash and 2008 subprime crisis has fueled the belief that the two classical paradigms of economics, which are the invisible hand and the rational agent, are not appropriate to describe market dynamics and should be abandoned at the benefit of alternative new theoretical concepts. At odd with such a view, using a simple model of choice dynamics from sociophysics, the invisible hand and the rational agent paradigms are given a new legitimacy....

  17. Radioactivity in the galactic plane

    Science.gov (United States)

    Walraven, G. D.; Haymes, R. C.

    1976-01-01

    The paper reports the detection of a large concentration of interstellar radioactivity during balloon-altitude measurements of gamma-ray energy spectra in the band between 0.02 and 12.27 MeV from galactic and extragalactic sources. Enhanced counting rates were observed in three directions towards the plane of the Galaxy; a power-law energy spectrum is computed for one of these directions (designated B 10). A large statistical deviation from the power law in a 1.0-FWHM interval centered near 1.16 MeV is discussed, and the existence of a nuclear gamma-ray line at 1.15 MeV in B 10 is postulated. It is suggested that Ca-44, which emits gamma radiation at 1.156 MeV following the decay of radioactive Sc-44, is a likely candidate for this line, noting that Sc-44 arises from Ti-44 according to explosive models of supernova nucleosynthesis. The 1.16-MeV line flux inferred from the present data is shown to equal the predicted flux for a supernova at a distance of approximately 3 kpc and an age not exceeding about 100 years.

  18. Focal Plane Instrumentation of VERITAS

    CERN Document Server

    Nagai, T; Sleege, G; Petry, D

    2007-01-01

    VERITAS is a new atmospheric Cherenkov imaging telescope array to detect very high energy gamma rays above 100 GeV. The array is located in southern Arizona, USA, at an altitude of 1268m above sea level. The array consists of four 12-m telescopes of Davies-Cotton design and structurally resembling the Whipple 10-m telescope. The four focal plane instruments are equipped with high-resolution (499 pixels) fast photo-multiplier-tube (PMT) cameras covering a 3.5 degree field of view with 0.15 degree pixel separation. Light concentrators reduce the dead-space between PMTs to 25% and shield the PMTs from ambient light. The PMTs are connected to high-speed preamplifiers allowing operation at modest anode current and giving good single photoelectron peaks in situ. Electronics in the focus box provides real-time monitoring of the anode currents for each pixel and ambient environmental conditions. A charge injection subsystem installed in the focus box allows daytime testing of the trigger and data acquisition system b...

  19. Duel-Plane Optical Disdrometer

    Science.gov (United States)

    Winsky, B. E.; Eichinger, W. E.

    2011-12-01

    Acquiring better drop-size distributions of rainfall will improve our understanding of the spatial and temporal variability of rainfall. In order to fully capture the spatial and temporal variability of rainfall, a robust, calibration free, low-cost instrument that provides an accurate drop-size distribution is required. Therefore, The University of Iowa Lidar Group has developed and built a new duel-plane optical disdrometer that meets these criteria. Two sheets of laser light, vertically spaced by 1 cm are produced by two 670nm laser beams passing through a collecting lens and culminating lens, respectively. The two sheets of laser light then pass through a convex lens located 20 cm from the lasers that focuses the light on a photo detector. A computer reads in and stores the voltages at 10 kHz. The velocity, diameter, shape and drop-size distribution of raindrops are extracted from the voltage measurements. Rainfall data collected in Iowa City, IA tested our disdrometer's robustness and accuracy of providing drop-size distributions. Our distrometer is advantageous because it is simple, low-cost, and requires no calibration.

  20. Periodical plane puzzles with numbers

    CERN Document Server

    Rezende, Jorge

    2011-01-01

    Consider a periodical (in two independent directions) tiling of the plane with polygons (faces). In this article we shall only give examples using squares, regular hexagons, equilateral triangles and parallelograms ("unions" of two equilateral triangles). We shall call some "multiple" of the fundamental region "the board". We naturally identify pairs of corresponding edges of the the board. Figures 9 and 19-29, in this article, show different boards. The "border" of the board is represented by a yellow thick line, unless part of it or all of it is the edge of a face. The board is tiled by a finite number of polygons. Construct polygonal plates in the same number, shape and size as the polygons of the board. Adjacent to each side of each plate draw a number, or two numbers, like it is shown in Figures 1 and 18-29. Figure 1 shows the obvious possibility of having plates with simple drawings, coloured drawings, etc. Now the game is to put the plates over the board polygons in such a way that the numbers near eac...

  1. Failure analysis of parameter-induced simulation crashes in climate models

    Directory of Open Access Journals (Sweden)

    D. D. Lucas

    2013-01-01

    Full Text Available Simulations using IPCC-class climate models are subject to fail or crash for a variety of reasons. Quantitative analysis of the failures can yield useful insights to better understand and improve the models. During the course of uncertainty quantification (UQ ensemble simulations to assess the effects of ocean model parameter uncertainties on climate simulations, we experienced a series of simulation crashes within the Parallel Ocean Program (POP2 component of the Community Climate System Model (CCSM4. About 8.5% of our CCSM4 simulations failed for numerical reasons at combinations of POP2 parameter values. We apply support vector machine (SVM classification from machine learning to quantify and predict the probability of failure as a function of the values of 18 POP2 parameters. A committee of SVM classifiers readily predicts model failures in an independent validation ensemble, as assessed by the area under the receiver operating characteristic (ROC curve metric (AUC > 0.96. The causes of the simulation failures are determined through a global sensitivity analysis. Combinations of 8 parameters related to ocean mixing and viscosity from three different POP2 parameterizations are the major sources of the failures. This information can be used to improve POP2 and CCSM4 by incorporating correlations across the relevant parameters. Our method can also be used to quantify, predict, and understand simulation crashes in other complex geoscientific models.

  2. Road traffic crashes in rural setting:an experience of a middle-income country

    Institute of Scientific and Technical Information of China (English)

    Ali Davoudi-Kiakalayeh; Reza Mohammadi; Shahrokh Yousefzade-Chabok; Sohiel Saadat

    2014-01-01

    Objective: To date, there has been little information published on the death of rural road accident deaths. This study uses burden of injury method to explore a more accurate estimate of years of life lost due to road traffic crashes occurring over a four-year period in Guilan province, northern Iran. Methods: Rural road accident deaths from 2009 to 2013 were extracted from Iran’s Forensic Medicine System, Death Registry System and Road Trauma Research center database. Results: During the study period, the average years of life lost due to motor vehicle crashes was 13.8 per 1 000 persons, ranging from 11.9 during March 2011-2012 to 15.8 per 1 000 persons during March 2012-2013. Conclusion: Road accident deaths in 2013 remained at the same high level as in 2009. The information obtained from this study provides a new perspective on fatal road traffic crash victims in rural settings and show us that more attention is needed in this area.

  3. Road traffi c crashes in rural setting: an experience of a middle-income country

    Directory of Open Access Journals (Sweden)

    Davoudi-Kiakalayeh Ali

    2014-12-01

    Full Text Available 【Abstract】Objective: To date, there has been little information published on the death of rural road accident deaths. This study uses burden of injury method to explore a more accurate estimate of years of life lost due to road traffic crashes occurring over a four-year period in Guilan province, northern Iran. Methods: Rural road accident deaths from 2009 to 2013 were extracted from Iran’s Forensic Medicine System, Death Registry System and Road Trauma Research center database. Results: During the study period, the average years of life lost due to motor vehicle crashes was 13.8 per 1 000 persons, ranging from 11.9 during March 2011- 2012 to 15.8 per 1 000 persons during March 012-2013. Conclusion: Road accident deaths in 2013 remained at the same high level as in 2009. The information obtained from this study provides a new perspective on fatal road traffi c crash victims in rural settings and show us that more attention is needed in this area. Key words: Accidents, traffi c; Iran; Mortality

  4. Full-Scale Crash Test of a MD-500 Helicopter with Deployable Energy Absorbers

    Science.gov (United States)

    Kellas, Sotiris; Jackson, Karen E.; Littell, Justin D.

    2010-01-01

    A new externally deployable energy absorbing system was demonstrated during a full-scale crash test of an MD-500 helicopter. The deployable system is a honeycomb structure and utilizes composite materials in its construction. A set of two Deployable Energy Absorbers (DEAs) were fitted on the MD-500 helicopter for the full-scale crash demonstration. Four anthropomorphic dummy occupants were also used to assess human survivability. A demonstration test was performed at NASA Langley's Landing and Impact Research Facility (LandIR). The test involved impacting the helicopter on a concrete surface with combined forward and vertical velocity components of 40-ft/s and 26-ft/s, respectively. The objectives of the test were to evaluate the performance of the DEA concept under realistic crash conditions and to generate test data for validation of dynamic finite element simulations. Descriptions of this test as well as other component and full-scale tests leading to the helicopter test are discussed. Acceleration data from the anthropomorphic dummies showed that dynamic loads were successfully attenuated to within non-injurious levels. Moreover, the airframe itself survived the relatively severe impact and was retested to provide baseline data for comparison for cases with and without DEAs.

  5. Full-scale crash test and FEM simulation of a crashworthy helicopter seat

    Institute of Scientific and Technical Information of China (English)

    HU Da-yong; ZHANG Xiang

    2012-01-01

    Crashworthy seat structure with considerable energy absorption capacity is a key component for aircraft to improve its crashworthiness and occupant survivability in emergencies. According to Federal Aviation Administration(FAA) regulations, seat performance must be certified by dynamic crash test which is quite expensive and time-consuming. For this reason, numerical simulation is a more efficient and economical approach to provide the possibility to assess seat performances and predict occupant responses. A numerical simulation of the crashworthy seat structure was presented and the results were also compared with the full-scale crash test data. In the numerical simulation, a full-scale three-dimensional finite element model of the seat/occupant structure was developed using a nonlinear and explicit dynamic finite element code LS-DYNA3D. Emphasis of the numerical simulation was on predicting the dynamic response of seat/occupant system,including the occupant motion which may lead to injuries,the occupant acceleration-time histories, and the energy absorbing behavior of the energy absorbers. The agreement between the simulation and the physical test suggestes that the developed numerical simulation can be a feasible substitute for the dynamic crash test.

  6. CRASH SAFETY OF A TYPICAL BAY TABLE IN A RAILWAY VEHICLE

    Directory of Open Access Journals (Sweden)

    Emmanuel MATSIKA

    2015-12-01

    Full Text Available Increasingly, urban and high speed trains are incorporating tables (workstations as common railway vehicle interior furniture because passengers prefer seating by bay tables. Among table design characteristics, the most challenging is meeting crashworthiness requirements. Past accident data and sled test results have shown that in the event of railway vehicle frontal impact, occupants located in the bay seating are exposed to chest and abdominal injuries upon contact with tables resulting from secondary collision. In some cases tables have tended to be structurally weak; they easily detach from the side walls and/or floor mounting. Subsequently these become unguided missiles that strike occupants, resulting in injuries. This paper presents an analysis of the crash performance of a typical bay table. The results provide some understanding of the table’s crash safety, giving an indication of its impact aggression. Table materials are characterised using quasi-static compressive tests. In addition, experimental dynamic (impact tests are conducted using a pendulum representing a body block (mass. The results provide information about the possible loading of the table on the occupant in the event of a crash. Contact forces are compared with chest and abdominal injury tolerance thresholds to infer the collision injury potential. Recommendations are then made on design of bay tables to meet the “functional-strength-and-safety balance”.

  7. Dynamic programming-based hot spot identification approach for pedestrian crashes.

    Science.gov (United States)

    Medury, Aditya; Grembek, Offer

    2016-08-01

    Network screening techniques are widely used by state agencies to identify locations with high collision concentration, also referred to as hot spots. However, most of the research in this regard has focused on identifying highway segments that are of concern to automobile collisions. In comparison, pedestrian hot spot detection has typically focused on analyzing pedestrian crashes in specific locations, such as at/near intersections, mid-blocks, and/or other crossings, as opposed to long stretches of roadway. In this context, the efficiency of the some of the widely used network screening methods has not been tested. Hence, in order to address this issue, a dynamic programming-based hot spot identification approach is proposed which provides efficient hot spot definitions for pedestrian crashes. The proposed approach is compared with the sliding window method and an intersection buffer-based approach. The results reveal that the dynamic programming method generates more hot spots with a higher number of crashes, while providing small hot spot segment lengths. In comparison, the sliding window method is shown to suffer from shortcomings due to a first-come-first-serve approach vis-à-vis hot spot identification and a fixed hot spot window length assumption. PMID:27209154

  8. Toward an effective long-term strategy for preventing motor vehicle crashes and injuries.

    Science.gov (United States)

    Mawson, Anthony R; Walley, E Kenneth

    2014-08-01

    Casualties due to motor vehicle crashes (MVCs) include some 40,000 deaths each year in the United States and one million deaths worldwide. One strategy that has been recommended for improving automobile safety is to lower speed limits and enforce them with speed cameras. However, motor vehicles can be hazardous even at low speeds whereas properly protected human beings can survive high-speed crashes without injury. Emphasis on changing driver behavior as the focus for road safety improvements has been largely unsuccessful; moreover, drivers today are increasingly distracted by secondary tasks such as cell phone use and texting. Indeed, the true limiting factor in vehicular safety is the capacity of human beings to sense and process information and to make rapid decisions. Given that dramatic reductions in injuries and deaths from MVCs have occurred over the past century due to improvements in safety technology, despite increases in the number of vehicles on the road and miles driven per vehicle, we propose that an effective long-term strategy for reducing MVC-related injury would be continued technological innovation in vehicle design, aimed at progressively removing the driver from routine operational decision-making. Once this is achieved, high rates of speed could be achieved on open highways, with minimal risk of crashes and injury to occupants and pedestrians. PMID:25116634

  9. Toward an Effective Long-Term Strategy for Preventing Motor Vehicle Crashes and Injuries

    Directory of Open Access Journals (Sweden)

    Anthony R. Mawson

    2014-08-01

    Full Text Available Casualties due to motor vehicle crashes (MVCs include some 40,000 deaths each year in the United States and one million deaths worldwide. One strategy that has been recommended for improving automobile safety is to lower speed limits and enforce them with speed cameras. However, motor vehicles can be hazardous even at low speeds whereas properly protected human beings can survive high-speed crashes without injury. Emphasis on changing driver behavior as the focus for road safety improvements has been largely unsuccessful; moreover, drivers today are increasingly distracted by secondary tasks such as cell phone use and texting. Indeed, the true limiting factor in vehicular safety is the capacity of human beings to sense and process information and to make rapid decisions. Given that dramatic reductions in injuries and deaths from MVCs have occurred over the past century due to improvements in safety technology, despite increases in the number of vehicles on the road and miles driven per vehicle, we propose that an effective long-term strategy for reducing MVC-related injury would be continued technological innovation in vehicle design, aimed at progressively removing the driver from routine operational decision-making. Once this is achieved, high rates of speed could be achieved on open highways, with minimal risk of crashes and injury to occupants and pedestrians.

  10. Probabilities of aircraft crashes at Rocky Flats and subsequent radioactive release

    International Nuclear Information System (INIS)

    The probability of a small airplane from Jefferson County Airport (Jeffco) or Stapleton International Airport crashing into a plutonium area at the Rocky Flats Plant has been calculated at 1.4 x 10-4 and 4.2 x 10-6 per year, respectively. The probability of such a crash involving a large airplane from Jeffco or Stapleton is 3.5 x 10-6 and 1.1 x 10-6 per year, respectively. Overall, the chance of an aircraft of any size, or any type, and from any source crashing into a plutonium area at Rocky Flats is 2.88 x 10-4 per year. An event tree was developed to cover every plausible series of events leading to a release of plutonium in the range of 0 to 1000 grams. Selected results show an annual release probability of 3.9 x 10-5 for less than 0.5 grams, 5.8 x 10-6 for 50 to 70 grams, 5.6 x 10-8 for 200 grams, and 6.4 x 10-10 for 1000 grams. Calculations led to a weighted average release amount of 3.7 x 10-4 grams of plutonium per year. Because of conservative assumptions, it is estimated that these probabilities are high by a factor of about two for small aircraft and 10 for large aircraft

  11. Crash injury risk behavior in adolescent latino males: the power of friends and relational connections.

    Science.gov (United States)

    Vaca, Federico E; Anderson, Craig L

    2011-01-01

    The adolescent Latino male mortality profile is an anomaly when compared to an otherwise more favorable overall U.S. Latino population mortality profile. Motor vehicle crash fatalities bear a considerable proportion of mortality burden in this vulnerable population. Friend influence and relational connection are two contextual domains that may mediate crash injury risk behavior in these adolescents. Our study goal was to assess the role of friend influence over time and relational connections associated with crash injury risk behavior (CIRB) in adolescent Latino males. Waves I and II data from the National Longitudinal Study of Adolescent Health were used. Scale of CIRB, and three relational connections; school connectedness, parent connectedness, and expectation of academic success were developed and tested. Friend nomination data were available and the index student responses were linked to friend responses. Linear regression was used to assess the relationship of relational connections and friend CIRB on index student CIRB at wave I and II. Longitudinal analysis did not show significant evidence for friend influence among adolescent Latino males on CIRB. The best predictor of CIRB at wave II for adolescent Latino males was their CIRB at wave I. Relational connections were important yet exaggerated cross-sectionally but their effect was substantially attenuated longitudinally. The lack of friend influence on CIRB for adolescent Latino males may be specific to this demographic group or characteristic of the sample studied. Prevention strategies that focus on modulating friend influence in adolescent Latino males may not yield the desired prevention effects on CIRB. PMID:22105382

  12. Neural network based approach for time to crash prediction to cope with software aging

    Institute of Scientific and Technical Information of China (English)

    Moona Yakhchi; Javier Alonso; Mahdi Fazeli; Amir Akhavan Bitaraf; Ahmad Patooghy

    2015-01-01

    Recent studies have shown that software is one of the main reasons for computer systems unavailability. A growing ac-cumulation of software errors with time causes a phenomenon cal ed software aging. This phenomenon can result in system per-formance degradation and eventual y system hang/crash. To cope with software aging, software rejuvenation has been proposed. Software rejuvenation is a proactive technique which leads to re-moving the accumulated software errors by stopping the system, cleaning up its internal state, and resuming its normal operation. One of the main chal enges of software rejuvenation is accurately predicting the time to crash due to aging factors such as me-mory leaks. In this paper, different machine learning techniques are compared to accurately predict the software time to crash un-der different aging scenarios. Final y, by comparing the accuracy of different techniques, it can be concluded that the multilayer per-ceptron neural network has the highest prediction accuracy among al techniques studied.

  13. Built environment effects on cyclist injury severity in automobile-involved bicycle crashes.

    Science.gov (United States)

    Chen, Peng; Shen, Qing

    2016-01-01

    This analysis uses a generalized ordered logit model and a generalized additive model to estimate the effects of built environment factors on cyclist injury severity in automobile-involved bicycle crashes, as well as to accommodate possible spatial dependence among crash locations. The sample is drawn from the Seattle Department of Transportation bicycle collision profiles. This study classifies the cyclist injury types as property damage only, possible injury, evident injury, and severe injury or fatality. Our modeling outcomes show that: (1) injury severity is negatively associated with employment density; (2) severe injury or fatality is negatively associated with land use mixture; (3) lower likelihood of injuries is observed for bicyclists wearing reflective clothing; (4) improving street lighting can decrease the likelihood of cyclist injuries; (5) posted speed limit is positively associated with the probability of evident injury and severe injury or fatality; (6) older cyclists appear to be more vulnerable to severe injury or fatality; and (7) cyclists are more likely to be severely injured when large vehicles are involved in crashes. One implication drawn from this study is that cities should increase land use mixture and development density, optimally lower posted speed limits on streets with both bikes and motor vehicles, and improve street lighting to promote bicycle safety. In addition, cyclists should be encouraged to wear reflective clothing. PMID:26609666

  14. Numerical Reconstruction and Injury Biomechanism in a Car-Pedestrian Crash Accident

    Institute of Scientific and Technical Information of China (English)

    ZOU Dong-hua; LI Zheng-dong; SHAO Yu; FENG Hao; CHEN Jian-guo; LIU Ning-guo; HUANG Ping; CHEN Yi-jiu

    2012-01-01

    Objective To reconstruct a car-pedestrian crash accident using numerical simulation technology and explore the injury biomechanism as forensic evidence for injury identification.Methods An integration of multi-body dynamic,finite elcment (FE),and classical method was applied to a car-pedestrian crash accident.The location of the collision and the details of the traffic accident were determined by vehicle trace verification and autopsy.The accident reconstruction was performed by coupling the three-dimensional car behavior from PC-CRASH with a MADYMO dummy model.The collision FE models of head and leg,developed from CT scans of human remains,were loaded with calculated dummy collision parameters.The data of the impact biomechanical responses were extracted in terms of von Mises stress,relative displacement,strain and stress fringes.Results The accident reconstruction results were identical with the examined ones and the biomechanism of head and leg injuries,illustrated through the FE methods,were consistent with the classical injury theories.Conclusion The numerical simulation technology is proved to be effective in identifying traffic accidents and exploring of injury biomechanism.

  15. Signal processing for plane wave actuators

    OpenAIRE

    T. Corbach; Holters, M.; U. Zölzer

    2010-01-01

    Plane wave actuators without an enclosure per se have a forward and backward radiation. The backward radiation is unwanted in many applications when a single direction radiation is desired. To avoid the disadvantages of an enclosure a system is proposed, which provides a high suppression of the unwanted backward radiation using a pair of plane wave actuators. This is achieved by adapted input signal filters. The influences of the second plane wave actuator to the forward rad...

  16. Nanostructured carbon films with oriented graphitic planes

    International Nuclear Information System (INIS)

    Nanostructured carbon films with oriented graphitic planes can be deposited by applying energetic carbon bombardment. The present work shows the possibility of structuring graphitic planes perpendicular to the substrate in following two distinct ways: (i) applying sufficiently large carbon energies for deposition at room temperature (E>10 keV), (ii) utilizing much lower energies for deposition at elevated substrate temperatures (T>200 deg. C). High resolution transmission electron microscopy is used to probe the graphitic planes. The alignment achieved at elevated temperatures does not depend on the deposition angle. The data provides insight into the mechanisms leading to the growth of oriented graphitic planes under different conditions.

  17. Enumeration of Cylindric Plane Partitions - part I

    CERN Document Server

    Langer, Robin

    2012-01-01

    Cylindric plane partitions may be thought of as a natural generalization of reverse plane partitions. A generating series for the enumeration of cylindric plane partitions was recently given by Borodin. The first result of this paper is a $(q,t)$-analog of Borodin's identity which extends previous work by Okada in the reverse plane partition case. Our proof uses commutation relations for $(q,t)$-vertex operators acting on Macdonald polynomials as given by Garsia, Haiman and Tesla. The second result of this paper is an explicit combinatorial interpreation of the $(q,t)$-Macdonald weight in terms of a non-intersecting lattice path model on the cylinder.

  18. Large Format Uncooled Focal Plane Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Black Forest Engineering has identified innovative modifications in uncooled focal plane array (UFPA) architecture and processing that allows development of large...

  19. Effects of Smoke-Free Laws on Alcohol-Related Car Crashes in California and New York: Time Series Analyses From 1982 to 2008

    OpenAIRE

    Bernat, Debra H.; Maldonado-Molina, Mildred; Hyland, Andrew; Wagenaar, Alexander C

    2012-01-01

    We examined effects of New York and California’s statewide smoke-free restaurant and bar polices on alcohol-related car crash fatalities. We used an interrupted time-series design from 1982 to 2008, with 312 monthly observations, to examine the effect of each state’s lawonsingle-vehicle-nighttime crashes and crashes involving a driver with a blood alcohol concentration of 0.08 grams per deciliter or greater.

  20. Driver sleepiness and risk of motor vehicle crash injuries: A population-based case control study in Fiji (TRIP 12) ☆

    OpenAIRE

    Herman, Josephine; Kafoa, Berlin; Wainiqolo, Iris; Robinson, Elizabeth; McCaig, Eddie; Connor, Jennie; Jackson, Rod; Ameratunga, Shanthi

    2014-01-01

    Introduction Published studies investigating the role of driver sleepiness in road crashes in low and middle-income countries have largely focused on heavy vehicles. We investigated the contribution of driver sleepiness to four-wheel motor vehicle crashes in Fiji, a middle-income Pacific Island country. Method The population-based case control study included 131 motor vehicles involved in crashes where at least one person died or was hospitalised (cases) and 752 motor vehicles identified in r...