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81.
以位于自然保护区边缘的火电厂建设项目环境影响评价为实例,阐述了火电厂生态环境评价中对自然保护区珍稀鸟类的保护方法,以供类似项目的生态环境影响评价借鉴。  相似文献   
82.
Cascade-based attack vulnerability on the US power grid   总被引:5,自引:0,他引:5  
The vulnerability of real-life networks subject to intentional attacks has been one of the outstanding challenges in the study of the network safety. Applying the real data of the US power grid, we compare the effects of two different attacks for the network robustness against cascading failures, i.e., removal by either the descending or ascending orders of the loads. Adopting the initial load of a node j to be Lj=[kjmΓjkm)]α with kj and Γj being the degree of the node j and the set of its neighboring nodes, respectively, where α is a tunable parameter and governs the strength of the initial load of a node, we investigate the response of the US power grid under two attacks during the cascading propagation. In the case of α<0.7, our investigation by the numerical simulations leads to a counterintuitive finding on the US power grid that the attack on the nodes with the lowest loads is more harmful than the attack on the ones with the highest loads. In addition, the almost same effect of two attacks in the case of α=0.7 may be useful in furthering studies on the control and defense of cascading failures in the US power grid.  相似文献   
83.
战时火力发电厂重要目标分类防护探讨   总被引:3,自引:2,他引:1  
基于重要目标防护准则和模糊聚类算法,构建火力发电厂目标评价准则指标体系和模糊聚类模型,实现了火力发电厂重要目标的分类防护,进而选用具有针对性的防护措施,解决了重要目标在战时防护措施选择不完善、不合理的问题,有效地提升了战时火力发电厂的生存能力;通过模糊聚类模型实现分类防护,不仅有利于提高重要目标防护效率,而且使得防护资源少、力量弱,供需突出的问题得以改善,同时,在应对自然灾害等重大突发事件发生时,有助于保护发电厂的生产能力。通过案例给出战时某火力发电厂的具体防护措施,合理地解决了发电厂重要目标和关键部位的防护问题。  相似文献   
84.
思索生产安全事故频发共性表象"违法、违章"背后的原因,提出"生产安全事故基因"概念。分析得出"去小概率性"、"社会责任缺失"和"非货币化产出分析能力短缺"3种生产安全事故基因,前两种基因是不可去基因,后一种是可去基因,三者会在不同的条件下以显性或隐性的形式呈现,并作用于生产过程;提出企业组织安全进化的常规对策——完善市场经济环境,创新对策——教育要为"安全"生产服务,强调学历教育系统在创新对策中的重要地位和作用。通过"基因"分析及其对策,为安全生产培养安全管理人员和相关人才,推动安全生产,实现经济与社会和谐发展。  相似文献   
85.
燃煤电厂烟气脱硫技术综合评价研究   总被引:1,自引:1,他引:0  
应用模糊数学原理和层次分析法,从经济、技术和环境三方面综合评价烟气脱硫技术,使烟气脱硫技术的选择更科学。以五种典型烟气脱硫技术为评价对象,应用该综合评价方法得出石灰石-石膏法较优的结论。  相似文献   
86.
Four different methods of epiphytic lichen mapping were used for the assessment of air quality in the region under the influence of the Sostanj Thermal Power Plant (Salek Valley, Slovenia). Three methods were based on the presence of different lichen species (VDI, EU and ICP-Forest), the fourth on a frequency and coverage assessment of different growth forms of epiphytic lichens, e.g. crustose, foliose and fruticose (SI). A comparison of the results from the assessment of air quality between forest sites (ICP-Forest, SI) and open areas (VDI, EU and SI), obtained by the different methods of epiphytic lichen mapping, is presented in the contribution. Data showed that lichen species richness is worse in forest sites in comparison with open areas. From the data obtained it can be concluded that epiphytic lichen mapping in open areas is a better method for the assessment of air pollution in a given area than mapping in forest sites. The species-based methods in open areas are more powerful and useful for air quality assessment in polluted research areas than the SI and ICP-Forest methods.  相似文献   
87.
An entrained-flow system has been designed and constructed to simulate in-flight mercury capture by sorbents in ducts of coal-fired utility plants. The test conditions of 1.5 s residence time, 140°C temperature, 4.5 ppbv inlet Hg0 concentration, and 0–20 lb/MMacf sorbent injection rates were chosen to simulate conditions in the ducts. Novel oxidants developed in previous fixed-bed tests and novel sorbents derived from the novel oxidants were tested for their Hg0 capture in the entrained-flow system to examine the possibility of using those sorbents in a full-scale system. Darco-FGD and Darco Hg-LH served as benchmark sorbents with which mercury control capability of the novel oxidants and novel sorbents could be compared. The test results showed that the novel oxidants have remarkable Hg0 oxidation capability, and the novel sorbents showed a better performance in Hg0 removal than Darco Hg-LH.  相似文献   
88.
Multicriteria decision support systems are applied in natural resource management in order to clarify the planning process for the stakeholders, to make all available information usable and all objectives manageable. Especially when the public is involved in planning, the decision support system should be easy to comprehend, transparent and fair. Social choice theory has recently been applied to group decision-making in natural resources management to accomplish these objectives. Although voting forms the basis of democracy, and is usually taken as a fair method, the influence of voters over the outcome may vary. It is also possible to vote strategically to improve the results from each stakeholder's point of view. This study examines the use of social choice theory in revealing stakeholders' preferences in participatory forest planning, and the influence of different voters on the outcome. The positional voting rules examined were approval voting and Borda count, but both rules were slightly modified for the purposes of this study. The third rule examined, cumulative rule, resembles utilitarian voting rules. The voting rules were tested in a real participatory forest planning situation in eastern Lapland, Finland. All voting rules resulted in a different joint order of importance of the criteria. Yet, the preference orders produced had also a lot in common and the criteria could be divided into three quite distinct groups according to their importance. The influence of individual voters varied between the voting rules, and in each case different voter was the most influential.  相似文献   
89.
为确定生物质能发电环境方面的可行性,分析了生物质能发电的工艺流程,相比于火电的优缺点,并进行了生物质能热电联厂的大气环境影响评价研究。结果表明:预测评价的烟尘、SO2和NO2排放浓度分别为11,63mg/m^3、200.3mg/m^3和378.7mg/m^3,均远低于火力发电的排放值;在不同条件下、不同地点SO2和NO2的1小时、日均浓度也均远低于火力发电的浓度值。说明了生物质能发电在环境友好性方面具有明显的优势。  相似文献   
90.
We develop a spectral framework for testing the hypothesis of complete spatial randomness (CSR) for a spatial point pattern. Five formal tests based on the periodogram (sample spectrum) proposed in Mugglestone (1990) are considered. A simulation study is used to evaluate and compare the power of the tests against clustered, regular and inhomogeneous alternatives to CSR. A subset of the tests is shown to be uniformly more powerful than the others against the alternatives considered. The spectral tests are also compared with three widely used space-domain tests that are based on the mean nearest-neighbor distance, the reduced second-order moment function (K-function), and a bivariate Cramér-von Mises statistic. The test based on the scaled cumulative R-spectrum is more powerful than the space-domain tests for detecting clustered alternatives to CSR, especially when the number of events is small.  相似文献   
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