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271.
针对多年来一直争论的过网网损分摊公平性问题,从功率平衡角度阐述了过网网损的本质。然后从过网网损本质和电力市场的公平性原则出发,深入分析了现有应用于过网网损计算的平均网损系数法模型,在此基础上提出了一种新的模型,该模型采用转供网送出功率与全网网损率的乘积作为过网网损,在完成过网网损计算的同时自动将过网网损合理分摊至区域内各受电主体。该模型一方面能够反映转供网送出功率与过网网损之间的关系,符合过网网损本质属性;另一方面区域内各主体采取降低自身电网网损的措施,在降低自身电网过网网损分摊量的同时,也降低了过网网损,即该模型对降低过网网损具有明确积极的指导意义。  相似文献   
272.
煤矿运输安全性的灰熵综合评价   总被引:1,自引:4,他引:1  
基于灰熵理论,提出一种新的安全性评价方法即灰熵综合评价。灰熵是离散序列均衡程度的测度,灰色关联度是参考序列和比较序列之间接近程度的测度。该法将灰色关联度和均衡度合成为均衡接近度,并以此作为评价准则,从而避免了低层次多因素权重确定的主观性,使评价模型更加合理,评价结果更加客观。通过利用多层次灰熵综合评价模型,对平顶山煤业(集团)有限责任公司六矿运输系统的安全性进行综合评价,其结果表明,该方法较其他评价方法更加客观,结论更符合实际,同时指出了今后运输安全管理工作的重点。  相似文献   
273.
ABSTRACT: Preservation of the few remaining ecologically vital riparian areas in the southwestern United States is a significant policy concern. This article reports on two economic aspects of preserving a nationally renowned riparian birding area in Southern California. First, the article examines visitor willingness to pay (WTP) for habitat restoration and estimates an annual WTP of US $77 per visitor to preserve the habitat, about a half‐million dollars a year for estimated visitor numbers in 2000 and 2001. Second, it documents visitor expenditures in the local economy to be approximately three‐quarters of a million dollars per year. This direct visitor spending attributable to the riparian habitat generates around US $1.3 million in increased local business activity in this relatively remote rural area.  相似文献   
274.
ABSTRACT: The Black River, a tributary of the Chehalis River in western Washington State, has a history of widespread low dissolved oxygen (DO), anoxia in some locations, and fish kills. As part of a Total Maximum Daily Load (TMDL) study, environmental data were collected during two summer dry seasons and simulations were conducted with the WASP5 model to assess the effect of biochemical oxygen demand ( BOD ), ammonia, and nutrient loads on DO in the Black River. DO levels were below the State water quality regulatory criterion of 8.0 mg/L in almost all locations during the study. The slow middle reach of the river showed stratified conditions, with anoxia in some of the deepest pools. Based on model simulations, DO was found to still fall below the 8.0 mg/L criterion in the entire mainstem under “natural” conditions, and eutrophication was identified as a potential problem in the middle reach. A TMDL was proposed for BOD and ammonia that would prevent significant degradation of DO in the Black River. To prevent eutrophic conditions in the Black River, a TMDL for total phosphorus was proposed that establishes a protective criterion of 0.05 mg/L for the middle river during the dry low-flow season.  相似文献   
275.
本文以生产力系统为研究对象,以布局效益为目标,通过资源要素、地区、产业之间关联关系的调查分析及其关联矩阵的确定,建立了生产力布局优化模型;并对湖南省16大主要工业行业布局进行了综合评价,为生产力布局的调整提供了重要的定量分析依据。  相似文献   
276.
ABSTRACT: Pricing policy in water allocation has become of more concern as some areas find water is indeed a scarce resource. Demand estimates, where the quantity purchased-value in use relationships are of concern, have been made in other studies for residential, industrial, and agricultural uses in many areas of the country. The price-quantity relations for water use in commercial firms are estimated and discussed for several different types of stores in this study. A derived demand model is used to estimate commercial demand in the Miami, Florida, area. The price elasticity was generally low (inelastic) for all groups studied except for department stores. This group was found to have an elastic demand for water at all prices above $0.93 per thousand gallons purchased per month, where the mean price for this part of the sample was $1.24. The major implication of the study is that commercial establishments may be responsive to price changes over the long run, much as has already been shown for other types of user groups in other studies.  相似文献   
277.
ABSTRACT: Low flow augmentation from multipurpose reservoirs may yield significant water quality benefits. Cost allocation assigns a portion of reservoir expense to water quality consumers, waste water dischargers who benefit from increased receiving flow. Whereas such allocation currently is not authorized for Federal projects, the procedure is increasingly appropriate for efficient multiobjective management. Waste water treatment costs, multipurpose reservoir costs, and water quality are modeled for Oregon's Willamette River. Water quality is expressed as a function of treatment and augmentation levels. Treatment cost necessary to achieve a given water quality without augmentation less treatment cost with augmentation is an alternative cost of water quality maintenance. With a cost allocation procedure, this alternative cost is used to determine water quality's share of reservoir cost. Under current conditions, water quality beneficiaries could be charged approximately seven percent of annualized reservoir expense. This charge is one-fourth the expense of additional treatment facilities required were augmentation not provided.  相似文献   
278.
ABSTRACT: Southeastern Montana's Tongue River basin is experienceing rapid development of its extensive coal deposits which is significantly impacting the basin's hydrologic systems. Energy development projects may require more water than is available and threatens to dewater the river, degrade water quality, and endanger aquatic econosystems. The Montana Water Use Act promised to end the uncertainty which has existed in Montana water law. However, serious difficulties have been encountered in implementing the law and Tongue River water rights remain in a state of uncertainty. The Tongue River's water was allocated in 1978 but the division of the river's water is meaningless due to Indian lawsuits and lack of an agreement between Montana and Wyoming concerning the Yellowstone River Compact. Thus water which is hydrologically available may not be legally available.  相似文献   
279.
ABSTRACT: As the many recreational uses of waterways have intensified, management agencies have increasingly turned to water surface zoning techniques to provide safe, equitable opportunities while also protecting aquatic habitats. Other publications have described the concept of water surface zoning; the study reported on was conducted to determine its current use nationwide. Depending on jurisdiction of the water surface in question and state legislation to zone water surfaces, nonfederal zoning regulations sometimes emanate directly from state government, and sometimes involve direct state and local government cooperation. Results of a national survey show that water surface zoning techniques employed by state and local governments in 1976–77 fall into five broad categories: restrictions on boat speed and horsepower, special use zoning, time zoining, protective space zoning, and limited density zoning. Examples of each are reported on in this paper.  相似文献   
280.
中国水资源需求管理及其政策评价   总被引:4,自引:0,他引:4  
本文从分析中国水资源问题入手,对水资源问题出路做了探索,认为建立并执行科学的水资源需求管理政策体系是中国21 世纪解决水问题,实现可持续发展战略的必由之路  相似文献   
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