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21.
《Ergonomics》2012,55(2):103-119
Au cours d'une plongée Active en atmosphere d'Helium-Oxygène (40 A.T.A. à saturation) trois sujets plongeura professionnels ont été souiius à une enquete quantifiée relative à leurs sensations de fatigue; paralleéement leur CFF (Critical flicker frequencyé a été déterminée. Les inesuros ont été faitos en surface, pendant un confinement à I'Heliox, pendant la compression, le séjour au fond, la décompression, et après retour-surfaco (durée de l'exploration: 16 jours). L'analyse statistique des résultats a conduit aux conclusions suivants: (1) Les signes subjectifs décelés ont consisté en baisse do vigilance et troubles physiques. (2) Ces signes sont plus marqués pendant la compression et la saturation. lis sont réduits en décompression, sans effet conaécutif certain. (3) Les signes de fatigue ne sont pas différents le matin et le soir. (4) La fréquence critique do papillotoment (CFF) est négativement correlée avec la profondeur. (5) Los modifications de CFF sont correlées avec le développement des signes subjectifs do fatigue. (6) La fatigue hyperbare est un syndrome hétérogèno oú la baisse de vigilance et les troubles physiques paraissent tenir une place majeure. 相似文献
22.
《Journal of Nuclear Science and Technology》2013,50(5):476-487
If an accident resulting in an emergency occurs at a nuclear facility, the emergency technical advisory body (ETAB) is asked to make technical advice to the national government for emergency response. In order for the ETAB to carry out its role, a significant amount of materials containing information on nuclear power plants is prepared in the ETAB. These materials are all paper copies and very voluminous. Therefore it is required that they should be computerized for more effective use. Further, methods should be developed which aid the ETAB to understand the status of the affected facility and to predict potential radioactivity release to the environment. To support the ETAB's activities in an emergency, the materials have been computerized as databases for more effective and quick use of them, and an expert system has been developed to quickly predict accident progression and environmental fission product release with the multivariate analysis method. The databases and the expert system have been unified to be a system of COSTA. The first phase of developing COSTA has been completed in FY1992. This paper describes the present status of development of COSTA. 相似文献
23.
《Ergonomics》2012,55(7):946-965
Three experiments examined some of the factors that might affect motorcyclists' conspicuity to other road users. In each case, subjects saw a sequence of slides showing traffic, some of which contained a motorcyclist. A record was taken of their reaction times to decide whether or not a motorcyclist was present in each slide. Experiments 1 and 2 examined the effects on conspicuity of headlight use, type of clothing, distance of motorcyclist from viewer, and driving situation (urban or semi-rural). Experiment 3 looked more closely at environmental influences on motorcyclist conspicuity, systematically varying the level of background ‘clutter’ behind the motorcyclist. All three experiments indicate that the effectiveness of the conspicuity aids used, especially clothing, may depend on the situation in which the motorcyclist was located: bright clothing and headlight use may not be infallible aids to conspicuity. Brightness contrast between the motorcyclist and the surroundings may be more important as a determinant of conspicuity than the motorcyclist's brightness per se. Motorcyclists' conspicuity is a more complex issue than has hitherto been acknowledged. 相似文献
24.
《Journal of Nuclear Science and Technology》2013,50(11):824-835
Massive ingress of air into the core of a high-temperature gas cooled reactor is among the accidents with a low occurrence frequency, but there are still gaps in understanding with respect to its consequences. In the present paper, massive air ingress combined with a delayed start of the afterheat removal system is investigated and compared to air ingress, accidents with normal operation of the afterheat removal procedure. A computer programme REACT/THERMIX used for these accident analyses is described. For a high-temperature gas cooled reactor with a pebble bed core, it is shown that massive air ingress has no real safety endangering consequences even if the operation of the afterheat removal system is delayed by 6 h. 相似文献
25.
本文对建筑施工企业安全管理问题进行了研究,并制定了相应的对策来解决这些问题,希望能为广大的建筑施工企业管理者提供一些参考。 相似文献
26.
《Ergonomics》2012,55(3):487-498
Abstract The significance of occupational falls is established through analysis of workers' compensation data of a major insurance company. The data covered 11%of the American privately insured workforce and exposure estimates were based on Bureau of Labor Statistics demographics. The number of incidents and the relative cost of falls were examined by age, gender, industry, climate and geographic region and empirical data are presented. These data establish the enormous cost of falls measured in terms of individual pain and suffering and in losses to industrial organizations. 相似文献
27.
针对水泥搅拌桩桩体强度不合格或承载力不满足设计要求等常见的质量事故,结合工程实际,介绍了换填法在处理水泥搅拌桩质量事故中的应用并阐述了实际效果,以期避免发生质量事故或将发生事故的可能性降至最低限度。 相似文献
28.
Background
Travel practices are changing: bicycle and motorized two-wheeler (MTW) use are rising in some of France’s large cities. These are cheaper modes of transport and therefore attractive at a time of economic crisis, but they also allow their users to avoid traffic congestion. At the same time, active transport modes such as walking and cycling are encouraged because they are beneficial to health and reduce pollution. It is therefore important to find out more about the road crash risks of the different modes of transport. To do this, we need to take account of the number of individuals who use each, and, even better, their travel levels.Method
We estimated the exposure-based fatality rates for road traffic crashes in France, on the basis of the ratio between the number of fatalities and exposure to road accident risk. Fatality data were obtained from the French national police database of road traffic casualties in the period 2007–2008. Exposure data was estimated from the latest national household travel survey (ENTD) which was conducted from April 2007 to April 2008. Three quantities of travel were computed for each mode of transport: (1) the number of trips, (2) the distance traveled and (3) the time spent traveling. Annual fatality rates were assessed by road user type, age and sex.Results
The overall annual fatality rates were 6.3 per 100 million trips, 5.8 per billion kilometers traveled and 0.20 per million hours spent traveling. The fatality rates differed according to road user type, age and sex. The risk of being killed was 20 to 32 times higher for motorized two-wheeler users than for car occupants. For cyclists, the risk of being killed, both on the basis of time spent traveling and the number of trips was about 1.5 times higher than for car occupants. Risk for pedestrians compared to car occupants was similar according to time spent traveling, lower according to the number of trips and higher according to the distance traveled. People from the 17–20 and 21–29 age groups and those aged 70 and over had the highest rates. Males had higher rates than females, by a factor of between 2 and 3.Conclusion
When exposure is taken into account, the risks for motorized two-wheeler users are extremely high compared to other types of road user. This disparity can be explained by the combination of speed and a lack of protection (except for helmets). The differential is so great that prevention measures could probably not eliminate it. The question that arises is as follows: with regard to public health, should not the use of MTW, or at least of motorcycles, be deterred? The difference between the fatality risk of cyclists and of car occupants is much smaller (1.5 times higher); besides, there is much room for improvements in cyclist safety, for instance by increasing the use of helmets and conspicuity equipment. Traffic calming could also benefit cyclists, pedestrians and perhaps moped users. 相似文献29.
The occurrence of accidents and injuries continues to be a major problem in construction worldwide. Even though accident statistics have been improving in most markets there are significant areas requiring further attention. The extent of integrated working between designers and constructors may be an instrumental factor. A comparison is undertaken of the accident performance of 55 large construction projects in the UK, with varying levels of design/construction integration as represented by procurement path. Although a statistical relationship between high levels of integration and low levels of accidents was weak, a follow‐up interview study provided strong support, suggesting that a lack of significance was related to the unreliability of the statistics available. The interview study also indicated reasons for this link. A key element in improved safety was seen to be better communications and a more positive relationship between designers and constructors. Further research into designing for safety for all procurement paths is recommended. 相似文献
30.
中国煤矿重大瓦斯爆炸事故规律分析 总被引:18,自引:1,他引:18
通过对中国煤矿1980年到2000年20年间发生的重大瓦斯爆炸事故和发生在国有重点煤矿的重大瓦斯爆炸事故的对比分析显示在所有导致中国煤矿重大瓦斯爆炸事故的直接原因中.人因(含故意违章45.89%、管理失误44.89%、缺陷设计6.90%)所占比率高达96.59%以上,这一数据在国有重点煤矿为人因(故意违章48.78%、管理失误35.36%、缺陷设计4.90%)占89.02%。这使我们对中国煤矿重大瓦斯爆炸事故的致因规律有了全新认识。在研究重大瓦斯爆炸事故环境特征、特征源交叉数据的基础上,对比得出中国煤矿雷大瓦斯爆怍事故规律图并分析。 相似文献