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31.
Risk Perception and Symptom Reporting   总被引:1,自引:0,他引:1  
  相似文献   
32.
Major accident risks posed by chemical hazards have raised major social concerns in today's China. Land‐use planning has been adopted by many countries as one of the essential elements for accident prevention. This article aims at proposing a method to assess major accident risks to support land‐use planning in the vicinity of chemical installations. This method is based on the definition of risk by the Accidental Risk Assessment Methodology for IndustrieS (ARAMIS) project and it is an expansion application of severity and vulnerability assessment tools. The severity and vulnerability indexes from the ARAMIS methodology are employed to assess both the severity and vulnerability levels, respectively. A risk matrix is devised to support risk ranking and compatibility checking. The method consists of four main steps and is presented in geographical information‐system‐based maps. As an illustration, the proposed method is applied in Dagushan Peninsula, China. The case study indicated that the method could not only aid risk regulations on existing land‐use planning, but also support future land‐use planning by offering alternatives or influencing the plans at the development stage, and thus further enhance the roles and influence of land‐use planning in the accident prevention activities in China.  相似文献   
33.
Emerging “prevention‐based” approaches to chemical regulation seek to minimize the use of toxic chemicals by mandating or directly incentivizing the adoption of viable safer alternative chemicals or processes. California and Maine are beginning to implement such programs, requiring manufacturers of consumer products containing certain chemicals of concern to identify and evaluate potential safer alternatives. In the European Union, the REACH program imposes similar obligations on manufacturers of certain substances of very high concern. Effective prevention‐based regulation requires regulatory alternatives analysis (RAA), a methodology for comparing and evaluating the regulated chemical or process and its alternatives across a range of relevant criteria. RAA has both public and private dimensions. To a significant degree, alternatives analysis is an aspect of product design; that is, the process by which private industry designs the goods it sells. Accordingly, an RAA method should reflect the attributes of well‐crafted product design tools used by businesses. But RAA adds health and environmental objectives to the mix of concerns taken into account by the product designer. Moreover, as part of a prevention‐based regulatory regime, it implicates important public values such as legitimacy, equity, public engagement, and accountability. Thus, an RAA should reflect both private standards and public values, and be evaluated against them. This article adopts that perspective, identifying an integrated set of design principles for RAA, and illustrating the application of those principles.  相似文献   
34.
In a job shop, because of large setup times, each operation is assigned to only one machine. There is no alternative routing. In a flexible manufacturing system, each manufacturing operation can often be performed on several machines. Therefore, with automated equipment, the capacity of a machine to perform certain operations is not independent of the capacity of other machines. Often, however, operations managers can use a route‐independent answer to production planning questions. For example, how much can be produced of a certain part type and when are important capacity questions in business negotiations, when the detailed routing and scheduling are not yet of interest or cannot be known. This paper provides a mathematical model for the route‐independent analysis of the capacity of flexible manufacturing systems based on a concept of operation types. An example is provided both to illustrate the use of operation types and to highlight the differences between the traditional route‐dependent and the proposed route‐independent formulations of capacity constraints. Some computational results are also given. Finally, a sensitivity analysis is developed to analyze the feasibility of production plans when production requirements and machine capacities can change.  相似文献   
35.
用综合财务指标衡量企业融资约束   总被引:1,自引:0,他引:1  
李焰  张宁 《中国管理科学》2008,16(3):145-150
投资现金流敏感性是关于企业融资约束研究中普遍采用的方法,但近十年以来对该方法的合理性有越来越多的争议。本论文以kaplan和Zingales的研究为基础,选择中国上市公司样本数据建立用于识别融资约束的综合财务指标评分模型,获得了可信度较高的度量企业融资约束的数值区间。研究结果为识别企业融资约束提供了可用的基本的方法,丰富了企业投资、融资研究和融资约束方面的研究。  相似文献   
36.
In study 1 different groups of female students were randomly assigned to one of four probabilistic information formats. Five different levels of probability of a genetic disease in an unborn child were presented to participants (within‐subject factor). After the presentation of the probability level, participants were requested to indicate the acceptable level of pain they would tolerate to avoid the disease (in their unborn child), their subjective evaluation of the disease risk, and their subjective evaluation of being worried by this risk. The results of study 1 confirmed the hypothesis that an experience‐based probability format decreases the subjective sense of worry about the disease, thus, presumably, weakening the tendency to overrate the probability of rare events. Study 2 showed that for the emotionally laden stimuli, the experience‐based probability format resulted in higher sensitivity to probability variations than other formats of probabilistic information. These advantages of the experience‐based probability format are interpreted in terms of two systems of information processing: the rational deliberative versus the affective experiential and the principle of stimulus‐response compatibility.  相似文献   
37.
化工技术开发项目的投资 ,主要包括有形资产投资和无形资产投资 .在作项目的经济评价时 ,要涉及从技术研究和开发阶段开始 ,直到项目建设实施阶段的全部资产价值 ,即从技术研究开发的成本和有形资产的成本两方面来考虑 .综合对项目资产和技术进行估价 ,以作为投资决策的依据 .本文将从理论上探讨化工技术开发项目的估价方法 ,包括项目的技术估价和资产估价 .  相似文献   
38.
研究了糖酵解反应模型(修正Selkov模型)双曲型反应-扩散方程的稳定性和化学振荡.与抛物型方程的结果比较表明,抛物型系统是双曲型系统当反应-扩散数增至无穷大时的特殊情况;双曲型系统不存在波速可能趋于无穷大的问题;二者的稳定性区域存在很大区别;双曲型系统更适合于用来研究糖酵解反应中的化学振荡.  相似文献   
39.
This exploratory study examines cognitive risk factors, anxiety sensitivity, and positive and negative affect, as related to the development of anxiety and depression. In a mailed survey, adolescents completed the Child Anxiety Sensitivity Index and the Positive and Negative Affectivity Scale. Previous research utilized the broad and unified variable of anxiety sensitivity as a predictor of anxiety. In this study, we separate and examine the four specific factors of anxiety sensitivity: mental incapacitation concerns, social concerns, disease concerns, and unsteady concerns, and relate it to specific anxiety disorders and depression. Results indicate good convergent validity and improved divergent validity when utilizing the four factors of anxiety sensitivity as compared to using it as one construct. Results also suggest: (1) OCD and GAD share numerous similarities and (2) the importance of the role of negative affectivity in anxiety and depression. Being aware of the components of anxiety sensitivity and how they relate to specific anxiety disorders can help a social worker when rendering a diagnosis. Part of the data presented in this article was from David A. Dia’s doctoral dissertation.  相似文献   
40.
化学传感器是当代信息产业的重要组成部分,其发展迅速,已在人类现代生活中发挥了重要的作用。本文介绍了化学传感器的基本概念,工作原理和分类,在此基础上着重总结了相关最新研究进展,并对化学传感器的发展做出了展望。  相似文献   
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