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Dear colleagues,
Does anyone know if there are any reference values (i.e., thresholds, service levels) for urban planning practices and analysis, considering the following indicators?
1) criminality/criminal occurrences (*)
2) accidents between vehicles and pedestrians
3) average volume of motorized traffic (in urban areas)
Are there international standards, for example, from ISO or another institution? I would appreciate it if anyone could point out a reference source (link to an article, report, or standard) to support the information.
Thank you for your attention.
_____________
(*) For crime, I found only the Homicide Rate as a reference indicator (but without thresholds). This indicator seems to me to be extremely limiting since it ignores other types of crimes that are more common and affect more people, such as robberies (with or without weapons) and theft, in addition to neglecting sexual crimes and assaults (also grave) and vandalism (lighter). It seems that focusing only on homicides is reductionist and omits other risks to the population.
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I suggest you to have a look at the following, interesting references:
- Global status report on road safety: time for action.
1.Accidents, Traffic - statistics and numerical data. 2.Accidents, Traffic - trends. 3.Wounds and injuries - epidemiology. 4.Safety - statistics and numerical data. 5.Data collection. I.World Health Organization. Dept. of Violence and Injury Prevention.
- TAG UNIT A4.1 - Social Impact Appraisal - GOV.UK
1 Social Impact Appraisal. 2 Accidents Impacts. 3 Physical Activity Impacts. 4 Security Impacts. 5 Severance Impacts. 6 Journey Quality Impacts and etc.
- Crime, Violence, and Development: Trends, Costs, and Policy Options in the Caribbean
A Joint Report by the United Nations Office on Drugs and Crime and the Latin America and the Caribbean Region of the World Bank
- Sustainable Transport Evaluation. Developing Practical Tools for Evaluation in the Context of the CSD Process
UNITED NATIONS DEPARTMENT OF ECONOMIC AND SOCIAL AFFAIRS
Commission on Sustainable Development. Nineteenth Session. 2-13 May 2011
My best regards, Amir Beketov.
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In the event like the Fukushima accident, if the turbine-driven pump fails, one can use accumulators to inject the store inventory into the SG for additional coping time. Why don't we do that?
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Dear Dr Shah,
I have seen in the thermal-hydraulics modeling of SBOs, this modification (injection of some numbersof accumulators into the SGs instead of primary circuit) will result in increase of coping time, but I think the answer to your question is very dependent to the NPP design and also consideration of other accidents. In other words it should be assessed case by case.
First, I consider an under operation PWR. This Plant is designed with specific numbers and configuration of accumulators, HPIS, LPIS and the associated accident analysis including (LOCA, SBO, MSLB, and ...) is performed considering these safety injections. Modification of Accumulators injection lines needs Re-assessment of all theses accidents and performance analysis of other injection systems, as the modification may be useful for SBO stand alone, but it may deteriorate the situation for some break sizes of LOCA or other accidents. Furthurmore, backfitting of the NPP should be assessed from the structural-civil work aspects and also some new setpoints, as this kind of modifications may need closing/ opening new penetration in the SG's piping, compartments of the containment and etc. but it doesn't mean that it's not applicable, this modification is more practical for NNP designs with larger number of accumulators or other sources of water that is capable of injecting water into SGs. You can find some studies that the SG shell side can be refilled by use of fire fighting hoses that are fed from outside of the containment.
For newer designs of NPPs and under construction NPPs, I have done some literature search and what I found is that the designers are more tended to use passive heat removal systems for condensing steam from SGs and send it back to them. these kind of systems can extend the coping time much more in comparison to accumulators injection into SGs.
Best Regards.
Alireza
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Dear Colleagues,
We would like to invite you to submit both original research and review articles to this Special Issue on "Accident Analysis and Prevention: Experimental & Numerical Approaches" organised by Applied Sciences (IF=1.689) ISSN 2076-3417 and Guest Edited by Prof. Ricardo J. Alves de Sousa and Dr. Mariusz Ptak.
In this Special Issue we expect to collect a set of contributions on topics that may include, but are not limited to the studies of human and environmental aspects prior to accidents; the type and severity of accidents; the design and implementation of passive and active protective devices; the biomechanics of impact and resulting injuries; and statistics and decision-making tools.
The submission deadline is 30 April 2019, yet the papers will be published immediately after acceptance.
Please find more information here:
Keywords
  • numerical simulation 
  • biomechanics 
  • composite materials 
  • protective devices 
  • road traffic accidents 
  • sports injuries 
  • crashworthiness 
  • accident analysis
  • accident prevention
Prof. Ricardo Alves de Sousa Dr. Mariusz Ptak Guest Editors
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Just an update - the current IF of Applied Sciences is now 2.217 (was 1.689).
Deadline for manuscript submissions: 31 July 2019
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Writing in the February 2019 edition of Accident Analysis & Prevention, researcher Laura S. Fruhen of the Future of Work Institute at Curtin University in Perth, Australia said: “Car drivers’ negative attitudes towards cyclists are linked with pro-automobility, but not environmental attitudes.”
An online survey of 308 motorists found antipathy towards cyclists whether or not they were wearing Spandex (Lycra) and riding in groups.
“A significant link between negative attitudes towards cyclists and aggressive behaviour addressed at cyclists was not moderated by the type of cyclist shown,”said Fruhen.
What is the cause of drivers aggression?
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Some motorists say cyclists are stealing their space in the road and that they shouldnt be allowed to use the roads.
In a personal experience, I was told I was "slowing" them.
I think bad experience with irresponsable cyclists could influence, in mi city there are a lot of cyclists who ignore red lights, make dangerous turns, etc, so some motorists use this as an argument.
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Machine learning; Real-time prediction; Accident analysis
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The basic idea is to detect changes in pitch, roll, and yaw by the sensor.
You can use the Kalman Filter for the real-time prediction.
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For a new research project dealing with the safety of young cyclists, I am looking for publications or in-depth studies related to bicycle accidents of children aged between 8 and 14 years. Any hints to publications or other material would be appreciated.
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You can find some statistics when scan data base by age category: www.sewik.pl - polish database of accidents.
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In my activity within ABRAM (Autonomous BRAking for Motorcycles) project, I am trying to evaluate the potential benefits of an autonomous emergency braking system applied to motorcycles (also known as MAEB). Currently the potential benefits are expressed in terms of impact speed reduction.
Common sense suggests that a reduction in the impact speed may lead to a reduction in the severity of the crash outcomes. However, only a proof of a correlation between some crash parameters and injury outcomes would provide the fundamental support for assessing the potential benefits of MAEB.
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The linear correlation between motorcycle crash speed, crash speed squared (as a measure of KE) and various measures of injury severity (ISS, AISmax, Brain AISmax, etc.) runs in the neighborhood of .25 - .35.  This was true for Hurt study, Thailand study and MAIDS data.   Terry Smith's 2009 MAIDS paper showed a significant correlation of precrash (running) speed and injury severity but not crash speed.  
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To some extent, the injury severity of accident consequences depends on the impact speed and other characteristics of collisions. We can make use of the information related to injury to conduct accident reconstruction and vehicle speed analysis. When the traces on the road surface and braking measure of drivers are uncertain, the parameters associated with injury severity (e.g. MAIS/ISS, fracture or some special injury) can be helpful to estimate the impact speed of vehicle or reconstruct the occupant status when the crash was happening (e.g. to inspect an occupant was driver or passenger; a road user was riding a bike or not). You are very welcome to talk with me on the related topics. Many thanks in advance.
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Agree with the view that going from injury severity to impact speed would be too reliable. Having done a lot of research review in this field in the past four years, I am not aware of any published work on this.
Determining delta-v from vehicle crush depth, skid marks and other crash dynamics evidence is a pretty standard crash reconstruction practice. There are publicly available US data sets of reconstructed crashes (+200,000 cases) held by National Highway Traffic Safety Administration (NHTSA). The data sets are called NASS/CDS and CIREN databases. Injury data is available there as well. Cases are weighted according to distribution of crash severities in the USA.
Delta-v can be used to theorise vehicle impact speeds, and the relationship to injury severity, although many limitations exist. We did this in a couple of recent papers among my uploaded publications.
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Nowadays, big data comes into our work and life, especially in relation to road traffic. There are massive video monitoring source of road traffic in China, particularly including occurred various crashes, which can be extracted from the cameras in vehicles or on roads or other places. By means of the vivid video record, we can observe and analyze the accident process, and judge what happened, who impact who and who is in duty. Also, the vehicle speed can be easily estimated by a simple calculation method based on the video, and accordingly the whole crash could be reconstructed. However, except for these applications mentioned, what else can be carried out. It is of importance to consider how to fully use the video record source and to perform data mining to obtain more findings for promoting traffic safety and accident prevention. Have you made use of video source of crashes in your work? Any suggestion is welcome! Thanks in advance!
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It is worth checking the experience gained in large naturalistic driving studies (NDS), for example SHRP2 (https://insight.shrp2nds.us/documents/shrp2_background.pdf). The issue is not how to collect data but how to process it afterwards. One has to define and apply various (semi)automatic triggers and also link them to the environment characteristics.
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Rear-end crashes involving multi-vehicle in expressways may be more serious in future. Now we are studying this crash type. For example, several vehicles follow each other with high speed and suddenly one of them goes wrong and serious crashes will occur. The characteristics, crash propagation, injury severity and influence factors should be focused. And the research methods could be mechanical modeling, accident reconstruction and computer simulation. Could you please introduce some relevant literature regarding multi-vehicle rear-end crashes? Thank you in advance!
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A recent Austroads study authored by my colleague at ARRB:
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Could you share with me this documents to compare characteristics like classification (primary, secondary, etc.), road width, lane width, separators, sidewalks dimensions, etc, with the real conditions of the roads in my city?
Thanks for your help!
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HI, if this is still an active question for you try the excellent answers and references I received for my recent question on urban local road safety. Most of the answers related to urban road safety in general.  
Very roughly: intersections and their design, land use, road standards, pedestrian movements.
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Do you remember the lovely hostesses and their beautiful tricycles in the opening ceremony of Rio 2016 Olympic Games? They are so cool! But do you know how many accidents related to tricycles? Now I'm studying the frequency, characteristics, severity and factor correlation of the accidents involving tricycles based on hundreds of crash cases. Here, the tricycles include man-power type and electric type. In China, these vehicles are very common and popular on roads. But now I hardly find any paper regarding this. Could you recommend some related papers for me? Thanks in advance.
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If you can not contact the authors contact me and maybe I can help.
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Tire burst is one of the causation of serious traffic crashes, especially for the cars at high speed. However, it is difficult to simulate this common phenomenon. Now we will use mechanical modeling, automobile theory and crash reconstruction to investigate tire burst of cars and related crashes. But it’s hard to find some existing papers regarding this. Could you recommend some related papers or give some suggestions for me? Thanks in advance.
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Look at the Nationalk Highway Traffic Safety Administration's regulatory impact analysis on tire pressure monitoring systems at  http://www.nhtsa.gov/DOT/NHTSA/Rulemaking/Rules/Associated%20Files/TPMS-2005-FMVSS-No138.pdf
Especially look at the analysis of impact on crashes.
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For long term trend of the number of crashes in a country, the weather conditions (long hard winter, warm spring and/or autumn) definitely are relevant.
Besides this, I have read about the relevance of the state of the economy as a further determinant of a rise or decrease of crashes several times. But the evidence always was from the US. I am curious if there is European evidence available, also.
I anybody aware of research from Europe, dealing with the influence of the weather and economic indicators on road crashes?
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In my country road safety information campaigns have not been used as a tool to reduce road accidents. Therefore, I assume that such a measure will have a good effect. However, we have experience in the development of such information campaigns. Where can I read the literature on the development of information campaigns, about the content, effectiveness evaluation, etc.
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According to my personal experience just because I worked in the past as a journalist for a specific campaign about road safety, I studied a bit the subject.
The client was a very relevant Italian PA with a consistent budget.
We share with those guys a panel of ideas and then they developed  a specific capaign utilizing an inhouse company.
The final result was to differentiate  the campaign through different medias .
They chose 3 different channel because it was in the late '90 during wich the social media had practically no existence.
So we proposed to select TV, radio and newspaper (divided in two groups, ie generalizated and specialized. The difference was to considered specialized if dedicated to a target focus of one scientific discipline.  So, for example, a financial newspaper was considered specialized instead a monthly journal for describing new and old cars was considered generalized).
In TV and in the radio the choice was to advertise in some particular hours like 6.00- 8.00 am and 6.00- 9.00 pm.
The message of 30'' or 1' was to describe what happened before an accident with deaths in wich, e. g., a child ask to his father: "dad, why did you decide to use your mobile phonewhen I say do not? " or a wife taking with her husband " you were in late but I didn't expect for dinner on time. I knew that were snowing. I told your on the phoneymoon be fore your leave the work". Others were about the the abuse of alcohol or drugs and even the cigarettes (the last was stopped by some tobacco lobby).
For specialized newspapers  we proposed to show inphograph about stats of accidents, number of deaths and serious  injuries with historic trends ( hoping they showed an improvement)
 For generalizated newspaper the message was with pictograms showing images of serious casualties and accidents.
Hoping to be a little bit useful. 
Luca
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Now I'm studying the characteristics and application of the envelop curve for the analysis on pedestrian-car accidents. But I can’t find any paper about this. Could you recommend some related papers for me? Thanks in advance.
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You may want to read the following paper. It is about application of WAD of pedestrians and bicyclists for head injuries. 
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Generally said, I plan to validate a specific indicator X (derived from driving behaviour) which should be linked to traffic safety (accidents) on level of road sections. Validation should statistically prove this relationship. I can think of various ways (i.e. possible study designs), but I would appreciate your opinions and advices.
Option 1 - I can define, based on theory or experience, two conditions when X is safe and when is unsafe. This can be compared to accidents / no accidents.
Option 2 - I can collect X on many sections and link it with accident history.
Option 3 - I can choose the critical sections (based on accidents) and collect X there - thus I should obtain "unsafe" values of X.
Option 4 - naturalistic driving study = studying the drivers behaviour visually. When they behave "unsafely", values of X will be "unsafe".
These are only my theories - please feel free to comment! I will welcome discussion, references, etc. Thank you.
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Option 1 would a validation exercise indeed. You can do this very simply by correlating the model and real outcome. There are several statistical methods depending on what outcomes you are comparing. One example I have is EuroRAP star rating vs. crash rates - two different variables, not directly comparable.
If you went with Option 2, e.g. a statistical modeling (accident prediction model), then you can use various residual plots as long as you got an independent sample not used in modelling. There are more sophisticated methods than that of course.
Option 3 could be modified by adding data from 'safe' sites. Then you are looking cross-tab analysis, the predecessor of statistical models. See answer for Option 2.
Option 3 - you are looking at proxy measures. As far as I understand this subject, it is the next frontier in road safety. Great for developing understanding of combined human, vehicle and road factors involved in crashes, i.e. everything that current statistical models do not do. The near future.
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I am doing a research on organizational factors related to the safety performance.I find that there are many studies focus on the unsafe acts of front-line operators,which also named human errors ,and have gained deep insight into their mechanism and characteristics from different perspectives.But I find few research papers have clear statements about the mechanism of organizational factors.Who should be responsible for organizational factors?Do some kind of human error lead to organizational factors?Whose human error,managers ,designers or someone else?
I  look forward to your helps!I appreciate if you can give me some references on my questions!
Thank you
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Hello Lin Zhou
please check pdf
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For vehicle to pedestrian crashes, statistics results show that females are at higher risk in crashes. Female pedestrians have more fatalities than males without regard to age, height, weight or other characteristics. Why female pedestrians or cyclists are generally vulnerable than males? Is it truly a gender difference? Is it because males are naturally stronger than females? But we have no further research work. Could you recommend me some related papers or existing research findings? Any suggestions are very welcome!
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To add to this: in this report
the scientist involved have found that in the age group 20 - 60 years old, male drivers had 1.5 higher risk (accidents/km) of a fatal accident than female drivers. However, for the non-fatal accidents, the risk of the women is 26% higher to get injured and 16% higher to get involved in an accident than men. So, one may in fact assign males a more risky driving-style, but only after proper normalization. However, this analysis was performed for the US in 1990; different areas and different times may provide different numbers.
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Perceived danger acts as a major barrier to the uptake of cycling as a sustainable mode of transport. Therefore, a greater understanding of how these perceptions arise and how they are overcome is necessary.
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Hi all,
I have published a new paper on this area, which uses mental mapping and a Generalised Linear Mixed Model to unpack perceived cycling risk: http://www.sciencedirect.com/science/article/pii/S0001457515301688
Richard
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I am fitting a SPF with Negative Binomial and the ADT was significant and negative. The data corresponds to rural mountainous with low traffic volume. Do you have any possible explanation for this? perhaps a similar experience? suggested references?
Thanks!
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Yes, congestions also came up my mind... But since AADT is usually used (which is aggregated annually), I would think it is not likely that congestion would influence this.
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Hi there, I'm doing crash count modelling based on road segment. There are two exposure variables in my data, 1. length of the road segment and 2. AADT. How can I include these two f variables in my modelling? Based on Stata, I can declare these variables as a exposure variable, with coefficient constrained to 1 or include these variables in modelling. What is the best way in dealing with these two variables?
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You are correct, both AADT and length are the typical exposure variables on a segment level.
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An ontology can help to organise occupational safety and health (OSH) knowledge and allow machines to interrogate OSH knowledge base to answer questions more intelligently. There are numerous accident and ill health classification taxonomies around, but are there comprehensive OSH ontology around? 
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 Thanks Deborah. Looks really useful. I'll read the paper. Is the ontology open access?
Mark, Appreciate the offer. I'll keep it in mind. Thanks.
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i wanna do research about mesoscopic traffic flow parameters which affect crash severity in urban highway. i know that mesoscopic parameters are combination of macroscopic & microscopic parameters. but what kinds of variable should i consider for making a crash severity models
thanks for your time and consideration
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Crash Severity on a urban highway, as on other roads, mainly depends on the kinetic energy. The kinetic energy by the speed. The speed by traffic flow, density, lane width, tortuosity of the route etc.
I would check the following parameters in function of the crash  severity:
number and width of lanes, traffic flows per lane (in passenger car equivalents per hour), composition of traffic flow, speed (85th percentile or speed diagrams for the entire path), speed differences among different types of vehicles (such as cars, vans, trucks etc).
The interdependence of these parameters and the crash severity should give you some good results.
Good work and good luck
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Crashes involving commercial vehicles (e g. Heavy-duty truck) are very serious. So it is crucial for these vehicles to be equipped with some practical active safety systems and driver assistant systems to avoid related accidents. Drivers are always in risky status, such as fatigue, sleepy, distraction, speeding, especially in adverse conditions of night, bad weather and visibility. Types of crashes usually include rear-end, frontal, side impact between vehicles and single-vehicle collision, which mainly have the characteristics of lane departure, speeding and with blind zone for large trucks. Due to so many casualties caused by these accidents in China, researchers should investigate some proper systems for trucks based on the contributing factors of crashes.
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In Europe, speed limiters are mandatory, and there are specific speed limits that the drivers must comply with, according to the type of roads. The itinerary must be provided to the law enforcement.
All heavy vehicles (for passengers and goods) must be equiped with a tachograph (analoge or digital) wich allows the law enforcement authorities to track the driving and rest periods, as well as the speed.
European laws are quite strict when it comes to avoid fatigue in driving so resting periods are compulsory and the company must keep the record of the data for control purposes. The driver must be able to provide the authorities the data of the last 28 days so that he can prove that he hasn´t been working more than he should.
The fines are heavy for the companies but, as in almost everything, the companies still find a way to get around the rule of law.
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Driving simulator is used to simulate the driving behavior like normal traveling on roads. It will stop the vehicle when crash happens. At that time, I always wonder why it couldn’t be designed as working continuously even a short period of time, and then we could know the behavior of drivers during collision. Due to the zero risk of this type of test, if necessary, maybe some accidents could be reconstructed through human involvement simulation in place of computer simulation.
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Dear Quan Yan,
Yes, you can continuously run the simulation post-crash, depending on your  simulation engine/software. We developed our own for research purposes and thus we are able to control the behaviour of the simulation software like what we want. Perhaps you might want to contact simulation professional software developers ( like drive square above ) for assistance. 
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Is adding Passive system with diversity high reliability in the safety systems the answer to sustained core decay heat removal for avoiding sever accident?
Is taxing the NPP operators with inaccurate severe accident analysis based SAMG justified?
What about the human reliability factor for SAMG implementation and success in preventing and mitigating sever accidents in new and existing NPPs?
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The European Council of 24/25 March, 2011, requested that the safety of all EU nuclear plants should be reviewed, on the basis of a comprehensive and transparent risk and safety assessment ("stress tests"). These “stress tests” are defined as targeted reassessments of the safety margins of nuclear power plants, developed by ENSREG, including the European Commission:
All nuclear power plants in the EU underwent stress tests and peer reviews in 2011 and 2012. Many other countries and territories also conducted comprehensive nuclear risk and safety assessments, based on the EU stress-test model. These include Switzerland and Ukraine (both of which fully participated in the EU stress tests), Armenia, Turkey, Russia, Taiwan, Japan, South Korea, South Africa and Brazil:
Follow-up of the peer review of the stress tests performed on European nuclear power plants - see:  http://www.ensreg.eu/EU-Stress-Tests/Follow-up
The March 2011 accident at the Fukushima Dai-ichi plant resulted in a new effort on the part of the nuclear industry to ensure that the existing SAMGs were as effective as possible. EPRI Report „Severe Accident Management Guidance Technical Basis Report Volume 1: Candidate High-Level Actions and Their Effects“, Final Report, October 2012, updates the original technical bases for SAMGs to reflect the lessons learned to date from the Fukushima Dai-ichi accident:
This update also incorporates insights gained from a substantial body of severe-accident research and analysis conducted since the original development.
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Data on Road Accidents in India is alarming.  It is in the order of several years.  You check on the data of Lose Prevention Association, Sion, India.  When I refer to International data, it is equally bad in many countries. What are the suggestions to the public to reduce the accidents on roads?
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you must use new technologies  like Intelligent transportation systems 
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What are the best method to compare frequency of two crash locations?
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If you have no denominator data for the sites (eg no of vehicles passing/unit time, population density of area) you could use a comparison of Poisson variables ,using  crash counts in successive time periods as basic data.
If you have denominator data you could use comparison of proportions with exact binomial statistics or normal approximation.
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For national (or regional) road safety evaluations and comparison we have been using two safety performance indicators (SPIs):
- direct (crashes, fatalities, injuries...)
- indirect (speed, speeding, seat belt use, daytime running lights use, cell phone use...)
Now I am trying to find some correlations between them. And I ask, for example: Should percent of speeding correlate with crash counts? or with fatalities? or injuries?
All is done on the level of country (or regions) - so direct SPIs are from national/regional statistics. Indirect SPIs are from surveys, typically 7 locations per region, once per year.
And lots of other questions, for example: when surveys are done in weekdays, spring/autumn, dry weather, should crashes to correlation also come only from the same conditions? (or possibly even only in the days/hours of survey?)
I will welcome any ideas on how to do these analyses, references, etc. Thank you in advance.
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When discussing correlations you have to keep in mind that correlations do not necessarily imply causal relations. Often, they are a consequence of a common influence by an ignored third factor such as properties of the infrastructure (many or few freeways), regional structure (predominantly urban or countryside), cultural properties,  (liberal or strict) legislation, (sloppy or stringent) control/enforcement. For example, in countries with liberal speed regulations (e.g., 75 or even 85 mph allowed on some roads) and sloppy enforcement (hardly any speed limit monitoring), few speed tickets are issued, i.e., the statistical data show little speeding. Nevertheless, in an objective sense, there may be many drivers driving too fast for the given situation resulting in comparatively many accidents.  This results in a paradoxical correlation with an unexpected sign between speeding and accidents.  This is a variant of the classical Simpson's paradox: The more firefighters are sent to the scene, the more damage the fire will  cause.
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Most data regarding sports accidents emanate from hospitals and rescuers. In France, it is somewhat difficult to get precise information as to these accidents. I would be interested in international data in order to compare the situation in France and in other countries...
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We are doing some research on prevalence of injuries among players Chhattisgarh, India.
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I applied a negative binomial model to evaluate whether toll highways PPP are safer than conventionally procured roads. To this end I have calibrated a negative binomial regression model covering years 2007-2009.
I sent the paper to a journal and the reviewer told me "The NB model employed is only suitable for a cross-sectional data. A more suitable model would be: random-effects or fixed-effects NB model”.
So, I was reading about the topic and would like to do a random effect NB model in SPSS. SPSS is more familiar to me, that is why I would like to do the model in that software.
thanks a lot!
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Dear Thais, 
Random-effects models become necessary when spatial correlation (data collected from the same geographic region) or temporal correlations (data collected con the same road section over successive time periods) are suspected to be present. It is to be said that random-effects  models are more especially appropriate for capturing respectively spatial or temporal correlations, but not a combination of the two.
Random-parameters models attempt to account for possible unobserved heterogeneity (unobserved factors that may vary across accident observations) by allowing the regression model coefficients to be random-parameters, in contrast with the assumption that parameters are considered to be constant across observations.
A special case in the class of random-parameters models is the so called random-intercept Negative Binomial model. In this model only the regression intercept is random, and this model is known in the literature to be equivalent to the random-effect Negative Binomial model.    
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I am aware that a large sample will be needed, but I am not aware of a formula to compute the sample size.
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A good paper that discuses this issue is "How Many Accidents Are Needed To Show A Difference?" by Ezra Hauer.  Here is a link to the article: http://www.sciencedirect.com/science/article/pii/S0001457508000535
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What are plausible explanations for these results which seem to contradict most other traffic safety studies (that have consistently found higher risks for men and for older cyclists).
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@Xochitl
Experience can certainly be a factor, but one which is hard to disentangle from a general decrease in risk taking behaviour with age (perhaps based on near misses or real accidents)
@Vincenzo
Distraction is certainly one of the top causes cited by cyclists involved in an accident in Belgium. However is it unclear to me why women would be more distracted than men (in Belgium and the other way around in other countries)
@Yves 
The population was limited to those of working age and mainly focussed on commuting so probably not due to differences in time activity pattern.
However on the gender issues I think you may have a point. Some of the men in the study reported really long commuting distances along e.g. canals where accident risk (per km cycled) is probably very low. On the other hand women seem to take trips more often in the rush hour (e.g. AB modelling by Beckx et al) and in town centres with more intersections and therefore higher risk (while their risk aversion while driving/cycling) may still be higher than that of men)
@Henk
Thank you for the Dutch graph. The reversal of male/female risk ratio with age is really interesting. The SHAPES sample was limited to those of working age (<65) and the number of observations in the +50y was indeed very low. On the other hand we are very confident in our assessment of the distance cycled which we observed frequently during a whole year.
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Please tell me where I can read the publication about criteria (measures), which allow to evaluate the quality of the road traffic management (such as delays cars, the number of traffic accidents, and other possible integral criteria). 
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In Brazil, the quality of service on rural highways are determined based on HCM. However, there are studies that have been produced to create appropriate methods to evaluate these roads. Some papers were published in english, but others are not published yet.
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I am look for literature on spray explosion
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A good starting point is the HSE information sheet on Explosion hazards due to spray releases: http://www.hse.gov.uk/offshore/infosheets/is1-2009.pdf 
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The correlation between vulnerable users ,especially those over 65, and proneness to red light running regarding drivers at road intersections.
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Dear Muath can you send me a copy of these paper?
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I am interested in the programs themselves, as well as scientific methods of their development. Also of interest is the assessment of their effectiveness (how much money is spent/what is the effect obtained). I am also interested in the programs of public transport development.
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Fines is the most effective method to improve road safety these days in my country.
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We can prevent over 90% of road accidents with few techniques and safe driving procedures.
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This is a known dilemma. If you make the road safer, the driver takes more risks. We call ourselfs an "intelligent life form" but we don't really act very intelligent. Espacially not while driving.
I personally think that the roads will only then be really safe, when WE stop driving and let the computers drive our vehicles. But that is still a distant future.
In the meantime we try to compansate the psychological errors of drivers by environmental measures.
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I have used stopped motion of a vehicle to detect accidents. As after the accident the vehicle's motion will be stopped, its position won't change and neither does the bounding box around it.
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Another suggestion is to detect the deacceleration rate. for example if the object goes from high speed to zero speed in a short period of time, that would be an indication of accident.
Combined by analyzing the change of the speed in the surrounding objects, sudden changes of some objects would be an indication also.
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Instead of other statistical or conventional approaches, what are the main reasons that are inductive for modelling?
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fuzzy data classification methods are suitable for complex data subject to uncertainties. The uncertain nature of noisy data requires the use of fuzzy methods.
Good luck
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The objetive is to analyse the injury severity of the crah victims using the MAIS scale.
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Dear Sara, dear Niels,
the following thesis
says that an attempt to translate ICD-10 to AIS 2005 update 2008 was only partly successful. In general, for me it seemed unsatisfactory and not recommendable without a lot of future improvements. For ICD-9 I cannot tell, but I would not suggest to use AIS 90 or 98 today, as the 2005 version is now the most updated scale. A translation from 98 to 2005 is provided on
but still no perfect fit is given.
Anyway: as different approaches towards injury coding are realised in ICD and AIS a translation will always be very limited.
If you have access to raw data (injuries) I'd suggest to code directly in AIS. Of course it needs some time, but the quality will be much better.
Kind regards
Sylvia
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Study design is descriptive cross sectional
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You could take a look at http://www.bmj.com/content/328/7444/857 a study of motorcyclists in New Zealand. Beware though, they went to great lengths to trace and contact MC drivers at 4 recieving hospitals and got a good response rate. If you don;t have resources for this your rep[sonse rate will be much lower and probably quite biased.
Best of luck
Phil