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481.
戴其文 《中国人口.资源与环境》2011,(Z1)
基于生态重要性,以重要物种空间分布种数为参数构建生物多样性保护重要性评价模型,以陇南市为例,乡镇为研究单元,基于模型对全市生物多样性保护重要性进行评价,基于评价结果将研究区分为优先补偿区、次级优先补偿区、次级补偿区和潜在补偿区,对各等级补偿区的特征分析结果表明:①各类补偿区分布相对集中,优先补偿区主要分布在陇南市南部,集中分布在文县。②各等级补偿区由高到低在补偿面积、补偿乡镇数量和补偿人口方面不断增加。③优先补偿区范围相对较小,而次级优先补偿区和次级补偿区范围相对较大,潜在补偿区占很大的比例。④优先补偿区与自然保护区有着密切的联系,大多数优先补偿乡镇位于自然保护区内。 相似文献
482.
483.
任何一项环境试验标准在描述试验条件与试验方法时。直接或间接地对其相应的试验设备提出了具体的要求。正确选用试验设备是保证试验准确性的前提,本文介绍了霉菌试验设备的选用及检定,同时建议建立一种新型的气候试验设备基本参数检定方法标准体系。 相似文献
484.
油气集输站场防爆区域的划分与电气设备的选用 总被引:1,自引:1,他引:0
结合作者近几年来对油田油气集输站场进行安全评价的实际情况,初步总结了油气集输站场爆炸危险区域划分和防爆电气设备选用的方法和步骤,并针对在油气集输站场安全现状评价过程中遇到的一些实际问题,提出了油气集输站场电气设备使用过程中的一些注意事项和应对措施。 相似文献
485.
湿法烟气脱硫除雾器设计选型和维护 总被引:1,自引:0,他引:1
分析了除雾器叶片的设计要求,比较了平板型和屋脊型除雾器的特点。从运行、维护的角度出发,建议建立除雾器检测和冲洗制度,以确保除雾器的安全、正常运行。 相似文献
486.
Introduction
In this paper, we show that FARS data can be a comparable alternative to observational NOPUS data in estimating seat belt use in the United States once we correct for sample selection bias.Results
Based on assumptions of independence for seatbelt choice, we establish a lower and upper bound for seatbelt usage rates, and find that once we correct for sample selection bias, the seatbelt usage estimates from the corrected FARS emerge at least as a comparable alternative to NOPUS estimates.Impact on Industry
This implies that researchers can use corrected FARS to complement NOPUS, thus being able to utilize the rich cross-sectional details available in FARS data to analyze various relevant research questions. 相似文献487.
D. O. Akinyele R. K. Rayudu Rodney H. G. Tan 《International Journal of Green Energy》2016,13(13):1352-1368
The module performance is an important consideration for selecting PV technologies for electricity production, as well as the economic aspect. Also, PV energy yield under varying environmental conditions is largely dependent on the type of technology used. Therefore, this article presents a comparative analysis of different PV modules, of the same power, namely, monocrystalline, polycrystalline, amorphous silicon and hybrid, based on performance, cost and space requirement. The performance is evaluated in terms of module power output, yield, capture losses, fill factor and efficiency, according to the IEC 61724 standards, using Gwako, Nigeria as a case study. A novel technique called Fundamental PV Module Performance Analysis is used to analyze and compare the performance of the PV modules. The performance of a single module is then employed to calculate the overall performance of a PV array designed for a small off-grid house, and a suitable module is determined amongst the modules under study. Results provide insights into the behaviors of the different technologies with the environmental factors of the location, which have an impact on their power and kWh/kW outputs and the efficiency. This knowledge, coupled with the understanding of the constraints of cost and the module space requirements would be useful to researchers, engineers, installers etc. in Nigeria, for planning and developing photovoltaic electric systems for off-grid applications. 相似文献
488.
Wild geese foraging on farmland cause increasing conflicts with agricultural interests, calling for a strategic approach to mitigation. In central Norway, conflicts between farmers and spring-staging pink-footed geese feeding on pastures have escalated. To alleviate the conflict, a scheme by which farmers are subsidized to allow geese to forage undisturbed was introduced. To guide allocation of subsidies, an ecological-based ranking of fields at a regional level was recommended and applied. Here we evaluate the scheme. On average, 40 % of subsidized fields were in the top 5 % of the ranking, and 80 % were within the top 20 %. Goose grazing pressure on subsidized pastures was 13 times higher compared to a stratified random selection of non-subsidized pastures, capturing 67 % of the pasture feeding geese despite that subsidized fields only comprised 13 % of the grassland area. Close dialogue between scientists and managers is regarded as a key to the success of the scheme. 相似文献
489.
Ahmad Mayyas Mohammed T. Hayajneh 《International Journal of Sustainable Engineering》2016,9(5):292-304
In the classical multiple attribute decision-making or MADM methods, the ratings and the weights of the criteria are known precisely. However, in eco-material selection exercises, the available data are typically inadequate because of the selection dual quantitative and qualitative natures. Some of the qualitative selection criteria can be rated in several classes rather being expressed by exact numerical values; hence the application of fuzzy concepts in decision-making seems attractive to deal with such kind of ratings. Thusly, the presented study attempts to propose an eco-material selection approach specific to the automobile body panels using a fuzzy technique for order preference by similarity to ideal solution (TOPSIS), to incorporate both numerical and rating-based criteria into one holistic sustainability model. TOPSIS and fuzzy logic can aid the material selection process in translating the design goals and parameters into usable numbers that in turn can be used to rank candidate materials in their closeness to the ideal solution. An additional uniqueness of this study stems from using the fuzzy-TOPSIS as a scoring tool without any assigned weights for the different selection attributes, in order to avoid the bias that is typically associated with other classical MADM, such as quality function deployment, analytical hierarchy process and digital logic. 相似文献
490.
城市污水处理厂工艺方案选择技术经济分析 总被引:1,自引:0,他引:1
城市污水处理厂需要较大的投资和运营费用.在我国目前经济条件比较落后,怎样用最少的钱达到最佳的处理效果非常关键.污水处理厂建设中最重要的就是污水处理工艺的选择.通过工程预算得到不同工艺不同规模的处理方案的总费用,通过曲线拟和得到不同工艺的费用和规模的函数关系式.根据技术经济学原理,将污水治理项目的费用和削减污染物的数量相联系,对项目的费用流和削减污染物负荷流进行贴现计算. 相似文献