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271.
Michael R. Greenberg Robert M. Hordon 《Journal of the American Water Resources Association》1976,12(4):669-680
ABSTRACT The relative economic costs of meeting projected public potable water demands through increasing the supply, controlling the demand, and increasing the capacity for interagency water transfers are explored. These alternatives and combinations are evaluated with the aid of a linear programming model in northeastern New Jersey, a major metropolitan region of over 4.5 million people, for the years 1975 to 2000. After more than 30 model tests it was found that a combination of increased interagency transfers and added water supplies was the least expensive solution. 相似文献
272.
Joachim Schleich David White 《Journal of the American Water Resources Association》1997,33(1):135-142
ABSTRACT: Linear programming is applied to identify the least cost strategy for reaching politically specified phosphorus and total suspended solids reduction targets for the Fox-Wolf river basin in Northeast Wisconsin. The programming model uses data collected on annualized unit reduction costs associated with five categories of sources of phosphorus and total suspended solids discharge in each of the 41 sub-watersheds in the basin to determine the least cost management strategy. Results indicate that: (1) cost-effective nutrient reduction requires careful selection of geographic areas and source categories to address throughout the watershed; (2) agricultural sources are the most cost-effective to address in the basin; and (3) care should be exercised in setting nutrient reduction targets, given that there are likely to be significantly increasing marginal costs of nutrient reduction; the model predicts that lowering the most restrictive target by 33 percent would cut reduction expenditures by about 75 percent. Policy implications of the model include support for the investigation and potential development of institutional arrangements that enable cost-effective nutrient reduction activities to occur, such as the creation of an agency with authority over a given watershed, coordinated watershed management activities, or nutrient trading programs. 相似文献
273.
Richard A. Andrews Richard R. Weyrick 《Journal of the American Water Resources Association》1973,9(2):258-272
ABSTRACT A linear programming model for a river basin was developed to include almost all water-related economic activity both for consumers and producers. The model was so designated that the entire basin or basin sub-division could be analyzed. The model included seven sectors, nine objective function criteria, and three river-flow levels. Economic basis for conflicts among sectors over incidence of cost allocation and level of economic activity can be traced to some chosen objective. The disposal of untreated household waste water, particularly from the rural household, directly into the river was consistent with maximizing net benefits and minimizing costs. The optimum resource allocation, water-treatment plants, farms and industry activities would change with flow level. For each of the three industries analyzed separately, paper, wool and tanning, public treatment of industrial waste water was the optimal treatment process in one or more of the solutions. Lake shoreline was the dominant feature determining lake-resource valuation. Implied capital value varied from $126 per shoreline foot to over $250 depending on discount rate. Implied prices on lake surface ranged from $42 to $147 per acre. Strong economic forces encouraged small lot sizes for vacation cottages. 相似文献
274.
Robert C. Ward David A. Link William M. Crosswhite 《Journal of the American Water Resources Association》1972,8(3):495-504
ABSTRACT This paper summarizes a study employing a systems approach for analyzing one class of modifications within a poultry processing plant. The modifications considered were changes in water-flow arrangements and process characteristics to reduce water intake of the plant and waste-treatment costs. The object of the study was to develop a technique or techniques by which a combination of proposed modifications could be chosen to minimize water flow through the plant. Existing and proposed flows were represented as a network, and linear programming was used to solve the minimum-flow problem for the network. Application of the technique was made to an existing, typical plant in Durham, N.C. Results of the application showed fresh water intake could be reduced by 45% to 51%, and furthermore that annual returns of 62% to 494% could be obtained on investment in the optimum modification sets, as fresh water costs varying from 10 cents to $1.00 per 1000 gal. Types of modifications of a poultry processing plant are classified by types, and the relative importance and effectiveness of each type are discussed. 相似文献
275.
陈中林 《防灾减灾工程学报》1994,(2)
文献研究给出了用线性模型曲线理论来计算地震加速度数据的反应谱理论.文献又给出了它的简便算法,但这算法忽视了强震丢头记录中初始点数据一般为非零值的影响.本文为此研究给出了更为普通和实用的包括初始数据点为任意值时的间便算法. 给出算例.将这线性模型理论的反应谱计算结果与作者新近研究的时限光滑化模型曲线精确理论计算结果作了对照,反映出用线性模型理论计算存在误差的状况. 相似文献
276.
采用火灾发生起数、死亡人数、受伤人数、直接经济损失、烧毁面积、受灾户数及人口火灾发生率7项指标构建河南省火灾风险评价综合体系,并用BP神经网络对该省份的18个地级市行政区的火灾风险进行评价,评价结果显示,该方法不但可以体现各地区的火灾风险相对水平,而且还可避免传统方法的主观性,具有较强的可行性和可靠性,对控制火灾风险、客观地反映各地区的消防工作现状具有一定的指导意义。 相似文献
277.
278.
燃煤二氧化硫排放量的回归测算模型 总被引:2,自引:0,他引:2
利用方差分析和多元线性回归分析的方法研究了二氧化硫排放量与原煤中可燃硫和不可燃硫含量的关系,建立了燃煤二氧化硫排放量的回归测算模型,并以山东省火电厂为例进行数值模拟.结果显示,所建回归测算模型模拟精度高,效果好,是二氧化硫排放量测算方法的重大改进. 相似文献
279.
280.
The flash point is one of the most important physicochemical parameters used to characterize the fire and explosion hazard for flammable liquids. The flash points of ternary miscible mixtures with different components and compositions were measured in this study. Four model input parameters, being normal boiling point, the standard enthalpy of vaporization, the average number of carbon atoms and the stoichiometric concentration of the gas phase for mixtures, were employed and calculated based on the theory of vapor–liquid equilibrium. Both multiple linear regression (MLR) and multiple nonlinear regression (MNR) methods were applied to develop prediction models for the flash points of ternary miscible mixtures. The developed predictive models were validated using data measured experimentally as well as taking data on flash points of ternairy mixtures from the literature. Results showed that the obtained average absolute error of both the MLR and the MNR model for all the datasets were within the range of experimental error of flash point measurements. It is shown that the presented models can be effectively used to predict the flash points of ternary mixtures with only some common physicochemical parameters. 相似文献