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61.
In 1982 the Council of the European Communities issued a Directive on the Major Accident Hazards of Certain Industrial Activities, commonly known as the Seveso Directive. Besides other requirements, the Directive specifies that members of the public liable to be affected by a major accident from certain industrial activities must be informed of safety measures and how they should behave in the event of an accident. The Directive was subsequently amended in an extensive way. Upon the transposition of the Seveso Directive and its amendments into national legislations, the 12 European Member States are faced with the task of "appropriately and effectively" informing the public about major accident hazards. Delays are observed throughout the community, both in transposing the Directives and implementing public information. A pilot study on "Risk Information Needs" was commissioned and carried out at two Seveso sites in Italy in order to begin to resolve some of the problems involved in the provision of public information and to suggest appropriate guidelines. One hundred subjects answered an experimental protocol designed to assess their "information needs." This article presents the theoretical background, the pragmatic aims, and the design of the study. It also summarizes its most relevant findings and suggests some recommendations for the provision of information to the public.  相似文献   
62.
在建立现代企业制度的探索中,原有的“承包制”在实践中已暴露它的不足,与改革的深入不相适应。企业的生机在于竞争和风险。在商品经济条件下,企业经营实际上就是经营者运用创新手段,将受损风险转化为超额收获。而企业生产经营所存在的诸多不确定因素,可以通过概率论中的中心极限定理和经验,借鉴计划评审法(PERT)中概率估算法对企业的经验风险度作出有价值的测定。  相似文献   
63.
Coherent decision analysis with inseparable probabilities and utilities   总被引:1,自引:0,他引:1  
This article explores the extent to which a decision maker's probabilities can be measured separately from his/her utilities by observing his/her acceptance of small monetary gambles. Only a partial separation is achieved: the acceptable gambles are partitioned into a set of belief gambles, which reveals probabilities distorted by marginal utilities for money, and a set of preference gambles, which reveals utilities reciprocally distorted by marginal utilities for money. However, the information in these gambles still enables us to solve the decision maker's problem: his/her utility-maximizing decision is the one that avoids arbitrage (i.e., incoherence or Dutch books).  相似文献   
64.
In electrical engineering, circuit designs are now often optimized via circuit simulation computer models. Typically, many response variables characterize the circuit's performance. Each response is a function of many input variables, including factors that can be set in the engineering design and noise factors representing manufacturing conditions. We describe a modelling approach which is appropriate for the simulator's deterministic input–output relationships. Non-linearities and interactions are identified without explicit assumptions about the functional form. These models lead to predictors to guide the reduction of the ranges of the designable factors in a sequence of experiments. Ultimately, the predictors are used to optimize the engineering design. We also show how a visualization of the fitted relationships facilitates an understanding of the engineering trade-offs between responses. The example used to demonstrate these methods, the design of a buffer circuit, has multiple targets for the responses, representing different trade-offs between the key performance measures.  相似文献   
65.
Mosler  Karl 《Theory and Decision》1997,42(3):215-233
Indices and orderings are developed for evaluating alternative strategies in the management of risk. They reflect the goals of reducing individual and collective risks, of increasing equity, and of assigning priority to the reduction and to the equity of high risks. Individual risk is defined as the (random or non-random) level of exposure to a danger. In particular the role of a lower negligibility level is investigated. A class of indices is proposed which involves two parameters, a negligibility level and a parameter of inequality aversion, and several interpretations of the indices are discussed. We provide a set of eight axioms which are necessary and sufficient for this class of indices, and we present an approach to deal with partial information on the parameters.  相似文献   
66.
This study considers the problem of inferring a functional evaluation criterion from existing performance measure policies. The objective is to develop a rational basis by which to adaptively evaluate a current best set of performance measures from alternative sets. The analysis is based on a matrix approach for relating system characteristics to performance measures across a set of activities. A procedure for ranking measure combinations which are candidate implementation alternatives is devised using this matrix representation and cost information. An example illustrating the procedure is presented.  相似文献   
67.
B. J. M. Ale 《Risk analysis》2005,25(2):231-241
In managing major accident hazards in industry risk, both the United Kingdom and the Netherlands use quantitative risk analysis and quantified risk criteria. These should be understood in the historical, legal, and political context in which they were drawn up. Even when criteria are numerically the same they do not necessarily mean the same thing. The legal and historical context differs widely between the two countries. Nevertheless, it is surprising that the final results in terms of land use and levels of risk are very similar.  相似文献   
68.
Quantitative Estimates of Risk for Noncancer Endpoints   总被引:2,自引:0,他引:2  
While quantitative estimates of risk have been a standard practice in cancer risk assessment for many years, no similar practice is evident in noncancer risk assessment. We use two recent examples involving methylmercury and arsenic to illustrate the negative impact of this discrepancy on risk communication and cost-benefit analysis. We argue for a more balanced treatment of cancer and noncancer risks and suggest an approach for reaching this goal.  相似文献   
69.
The 2003 Heat Wave in France: Dangerous Climate Change Here and Now   总被引:14,自引:0,他引:14  
In an analysis of the French episode of heat wave in 2003, this article highlights how heat wave dangers result from the intricate association of natural and social factors. Unusually high temperatures, as well as socioeconomic vulnerability, along with social attenuation of hazards, in a general context where the anthropogenic contribution to climate change is becoming more plausible, led to an excess of 14,947 deaths in France, between August 4 and 18, 2003. The greatest increase in mortality was due to causes directly attributable to heat: dehydration, hyperthermia, heat stroke. In addition to age and gender, combinatorial factors included preexisting disease, medication, urban residence, isolation, poverty, and, probably, air pollution. Although diversely impacted or reported, many parts of Europe suffered human and other losses, such as farming and forestry through drought and fires. Summer 2003 was the hottest in Europe since 1500, very likely due in part to anthropogenic climate change. The French experience confirms research establishing that heat waves are a major mortal risk, number one among so-called natural hazards in postindustrial societies. Yet France had no policy in place, as if dangerous climate were restricted to a distant or uncertain future of climate change, or to preindustrial countries. We analyze the heat wave's profile as a strongly attenuated risk in the French context, as well as the causes and the effects of its sudden shift into amplification. Research and preparedness needs are highlighted.  相似文献   
70.
This research was initiated to study lead levels in various food items in the city of Kanpur, India, to assess the dietary intake of lead and to estimate blood lead (PbB) levels, a biomarker of lead toxicity. For this purpose, sampling of food products, laboratory analysis, and computational exercises were undertaken. Specifically, six food groups (leafy vegetables, nonleafy vegetables, fruits, pulses, cereals, and milk), drinking water, and lead air concentration were considered for estimating lead intake. Results indicated highest lead content in leafy vegetables followed by pulses. Fruits showed low lead content and drinking water lead levels were always within tolerable limits. It was estimated that average daily lead intake through diet was about 114 microg/day for adults and 50 microg/day in children; tolerable limit is 250 microg/day for adults and 90 microg/day for children. The estimated lead intakes were translated into the resultant PbB concentrations for children and adults using a physiologically-based pharmacokinetic (PBPK) model. Monte Carlo simulation of PbB level variations for adults showed that probability of exceeding the tolerable limit of PbB (i.e.,10 microg/dL) was 0.062 for the pre-unleaded and 0.000328 for the post-unleaded gasoline period. The probability of exceeding tolerable limits in PbB level was reduced by a factor of 189 in the post-unleaded scenario. The study also suggested that in spite of the introduction of unleaded gasoline, children continue to be at a high risk (probability of exceeding 10 microg/dL = 0.39) because of a high intake of lead per unit body weight.  相似文献   
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