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1.
生命周期评价方法及其应用 总被引:6,自引:0,他引:6
介绍了生命周期评价的目的、意义和基本方法,并运用该方法对燃煤发电、废纸造纸、废旧塑料气化发电等几种不同工业过程的环境影响进行了分析。 相似文献
2.
涂立桥 《黄石理工学院学报》2005,21(5):1-5
从国债的可持续性、国债的货币扩张效应、国债对经济增长的影响三个层面评估了我国当前的国债风险,并针对我国的国债特点,提出了防范国债风险的措施。 相似文献
3.
There is widespread application of indicators to the assessment of environmental condition of streams. These indicators are intended for use by managers in making various comparative and absolute assessments and often have a role in resource allocation and performance assessment. Therefore, the problem of formally defining confidence in the results is important but difficult because the sampling strategies used are commonly based on a compromise between the requirements of statistical rigour and the pragmatic issues of access and resources. It is rare to see this compromise explicitly considered and consequently there is seldom quantification of the uncertainty that could affect the confidence a manager has in an indicator. In this paper, we present a method for quantitatively assessing the tradeoffs between sampling density and uncertainty in meeting various monitoring objectives. Assessments using judgement‐based representative reaches are shown to be unreliable; instead a sampling approach is recommended based on the random selection of measuring sites. A detailed dataset was collected along two streams in Victoria, Australia, and the effect of sampling density was assessed by subsampling from this dataset with precision related to the number of sites assessed per reach length and the intensity of the sampling at each site. The sampling scheme to achieve a given precision is shown to depend on the monitoring objective. In particular, three objectives were considered: (1) making a baseline assessment of current condition; (2) change detection; and (3) detection of a critical threshold in condition. Change detection is shown to be more demanding than assessing baseline condition with additional sampling effort required to achieve the same precision. Sampling to detect a critical threshold depends on nominating acceptable values of Type I and II error and the size of the effect to be detected. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
4.
应用突变多准则评价法对南水北调中线水源工程项目的多方案比选作出评价决策。该方法为专家决策系统提供一种数学方法 ,以便用计算机实现多目标、多层次、多方案的评价决策。 相似文献
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Practitioners and regulators are concerned that when auditors perceive management's attitude or character as indicative of low fraud risk, they are not sufficiently sensitive to high levels of incentive or opportunity risks in their overall fraud‐risk assessments. In this study, we examine whether a fraud‐triangle decomposition of fraud‐risk assessments (that is, separately assessing attitude, opportunity, and incentive risks prior to assessing overall fraud risk) increases auditors' sensitivity to opportunity and incentive cues when perceptions of management's attitude suggest low fraud risk. In an experiment with 52 practicing audit managers, we find that auditors who decompose fraud‐risk assessments are more sensitive to opportunity and incentive cues when making their overall assessments than auditors who simply make an overall fraud‐risk assessment. However, this increased sensitivity to opportunity and incentive cues appears to happen only when those cues suggest low fraud risk. When opportunity and incentive cues suggest high fraud risk, auditors are equally sensitive to those cues whether they use a decomposition or a holistic approach. We discuss and examine potential explanations for this finding. 相似文献
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本文分析了电力商标的实质内涵,总结了电力商标的基本特征,在此基础上对商标的评估模型进行了创新构建,新建模型有两大特点:一是将商标收益分割为两部分计量;二是用强度系数进行了调整强化,为电力商标的评估提供一种新思路。 相似文献
9.
Cleyo Harris Travis O. Brenden Chris S. Vandergoot Matthew D. Faust Seth J. Herbst Charles C. Krueger 《Journal of Great Lakes research》2021,47(1):48-58
Infrequent captures of invasive, non-native grass carp (Ctenopharyngodon idella) have occurred in Lake Erie over the last 30+ years, with recent evidence suggesting wild reproduction in the lake’s western basin (WB) is occurring. Information on grass carp movements in the Laurentian Great Lakes is lacking, but an improved understanding of large-scale movements and potential areas of aggregation will help inform control strategies and risk assessment if grass carp spread to other parts of Lake Erie and other Great Lakes. Twenty-three grass carp captured in Lake Erie’s WB were implanted with acoustic transmitters and released. Movements were monitored with acoustic receivers deployed throughout Lake Erie and elsewhere in the Great Lakes. Grass carp dispersed up to 236 km, with approximately 25% of fish dispersing greater than 100 km from their release location. Mean daily movements ranged from <0.01 to 2.49 km/day, with the highest daily averages occurring in the spring and summer. The Sandusky, Detroit, and Maumee Rivers, and Plum Creek were the most heavily used WB tributaries. Seventeen percent of grass carp moved into Lake Erie’s central or eastern basins, although all fish eventually returned to the WB. One fish emigrated from Lake Erie through the Huron-Erie Corridor and into Lake Huron. Based on our results, past assessments may have underestimated the potential for grass carp to spread in the Great Lakes. We recommend focusing grass carp control efforts on Sandusky River and Plum Creek given their high use by tagged fish, and secondarily on Maumee and Detroit Rivers. 相似文献
10.
为提高堤防工程风险评价的准确性,提出了基于极限学习机的堤防工程多元风险指标评价方法。首先,综合考虑影响堤防风险的28个评价指标,利用层次分析法从预警系统、堤防工程系统、环境系统和社会经济系统这4个方面建立了堤防工程多元风险评价指标体系。接着,基于极限学习机算法对28个指标进行标准化处理及分级标准构建,以风险指标作为输入量,分级隶属度作为输出量,划分风险等级,量化评价指标,估计多元风险评价指标值和判断风险的严重程度。最后,依托鄱阳湖重点堤防——康山大堤,构建多元风险评价指标体系,运用极限学习机算法计算多元风险评价指标值。评价结果表明:康山大堤目前处于基本安全水平,符合康山大堤经过两次加固后的工程实际情况,并与其他方法进行对比,验证了提出方法的可靠性和有效性。该方法可拓展应用到其他重要水工结构工程风险评估中。 相似文献