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721.
722.
G. Grasa V. Navarro O. Rubio J. A. Pea J. Santamaria 《Journal of Loss Prevention in the Process Industries》2002,15(6):525-530
Opinion polls were conducted to assess the level of risk perceived by the citizens in communities of different sizes where chemical industries were present. The aim of the study was to relate the risk perceived to variables such as the nature of risks, the specific information received regarding the industrial activity and the economic impact of this activity in the community. 相似文献
723.
724.
Shie‐Yui Liong Chandrasekaran Sivapragasam 《Journal of the American Water Resources Association》2002,38(1):173-186
ABSTRACT: Machine learning techniques are finding more and more applications in the field of forecasting. A novel regression technique, called Support Vector Machine (SVM), based on the statistical learning theory is explored in this study. SVM is based on the principle of Structural Risk Minimization as opposed to the principle of Empirical Risk Minimization espoused by conventional regression techniques. The flood data at Dhaka, Bangladesh, are used in this study to demonstrate the forecasting capabilities of SVM. The result is compared with that of Artificial Neural Network (ANN) based model for one‐lead day to seven‐lead day forecasting. The improvements in maximum predicted water level errors by SVM over ANN for four‐lead day to seven‐lead day are 9.6 cm, 22.6 cm, 4.9 cm and 15.7 cm, respectively. The result shows that the prediction accuracy of SVM is at least as good as and in some cases (particularly at higher lead days) actually better than that of ANN, yet it offers advantages over many of the limitations of ANN, for example in arriving at ANN's optimal network architecture and choosing useful training set. Thus, SVM appears to be a very promising prediction tool. 相似文献
725.
Kathryn Paxton George 《Journal of Agricultural and Environmental Ethics》1992,5(2):217-233
In response to Evelyn Pluhar'sWho Can Be Morally Obligated to Be a Vegetarian? in this journal issue, the author has read all of Pluhar's citations for the accuracy of her claims and had these read by an independent nutritionist. Detailed analysis of Pluhar's argument shows that she attempts to make her case by consistent misappropriation of the findings and conclusions of the studies she cites. Pluhar makes sweeping generalizations from scanty data, ignores causal explanations given by scientists, equates hypothesis with fact, draws false cause conclusions from studies, and in one case claims a conclusion opposite of what the scientist published. Such poor reasoning cannot be the basis of an argument for moral vegetarianism. A broader search of the literature and attention to reviews and textbooks in nutrition shows that each of Pluhar's claims is suspect or incorrect. Pluhar has not undermined my central claims: even if animals have certain rights and well-planned vegetarian diets are safe in complex industrialized societies, these diets cannot be so regarded if the presuppositions of high levels of wealth, education, and medical care do not exist; and, women, children, the aged and some ill persons are at greater risk on restrictive vegan diets. Thus, any duty of moral vegetarianism is not categorical but provisional in nature. 相似文献
726.
针对我国乡镇工业职业卫生面临的“高需求、低服务”。以及与农村初级卫生保健(PHC)相脱节问题。提出实施乡镇企业职业卫生与PHC相结合的必要性和迫切性。结合WHO职业卫生合作中心(上海)在华东地区的试点探索,提出两者结合的内容和方式的若干设想,强调从更新观念全面认识PHC和把职业卫生与安全作为PHC组成部分入手,深入实践,共同为卫生部领导下的全国性探索作贡献。 相似文献
727.
中国山区沟谷泥石流危险度的定量判定法 总被引:22,自引:5,他引:22
本文根据专家系统调查,确定了一次泥石流冲出物最大方量和泥石流暴发频率作为判定泥石流危险度的主要危险因子。运用灰色关联度分析,优选出10项判定泥石流危险度的次要危险因子,并根据关联序确定了它们的权重。在各危险因子等级划分的基础上,得出了泥石流危险度的定量计算公式。通过实例检验,证明该判定方法具有60%以上的可靠度。 相似文献
728.
Irving Spiewak 《Journal of the American Water Resources Association》1971,7(4):844-855
ABSTRACT The selection of an evaporator design must reflect the balancing of captial cost (primarily in heat exchanger surface and vessels) against operating cost (primarily steam cost) to achieve minimum cost. In a conjunctive plant the tendency is to select a low-capital cost, high-operating cost plant. In addition, it is advantageous to use a high-capacity plant which needs to be operated much less of the time than a plant which is sized just at the needed rate. For example, in the study of a possible system to satisfy a future increase of 450 MGD in water supply to New York Qty, a plant of 750 MGD capacity was selected as optimum. This plant, of the advanced VTE-MSF process type, would have a performance ratio of 9 lb product/1000 Btu as compared to 10-13 normally used for base-loaded plants. Steam would be supplied by a multi-unit dual-purpose nuclear power plant. The most economical type of energy supply would be “interruptible”; the steam would be used by a low pressure turbine to generate electricity during periods of peak electrical demand but would be available to the desalting plant at other times. The low pressure turbine would be available as spinning reserve during desalting plant operation. It is estimated that the desalting plant would have a load factor of 27 per cent over its life. 相似文献
729.
William L. Bathke R. J. Freund J. R. Conner 《Journal of the American Water Resources Association》1970,6(4):476-482
In this paper, a procedure for analyzing a water resource system with special emphasis on evaluation of acceptable economic risk due to occasional failures to deliver water is proposed. The basic methodology includes the development of a simple mathematical model which describes the physical hydrologic and economic characteristics of a single reservoir irrigation and city water supply system and an evaluation of economic benefits of the system with full and partial deliveries of water. The system is simulated for various combinations of decision variables (system magnitudes) and an optimum design is obtained by response surface technology. Emphasis is placed on the basic model and methodology although, in order to introduce some realism, the procedure is applied to data based on the existing reservoir system on the South Concho River in West Central Texas. 相似文献
730.
红外光谱法测定粉尘中游离二氧化硅综述 总被引:1,自引:1,他引:0
全面地回顾了国内外红外光谱法测定粉尘中游离二氧化硅的研究成果。系统而重点地介绍了溴化钾压片法、粉尘滤膜样品重沉积和采样滤膜直接测定技术,分析了样品粒度、标准石英物质和矿物干扰物对测定结果的影响及干扰消除方法;还介绍了国外对红外光谱法与X-射线衍射法进行比较性研究的结果和动态,并得出结论。文章所列参考文献对本领域研究人员和基层检测人员具有很高的参考价值。 相似文献