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141.
In this study, an inexact fuzzy-robust two-stage programming (IFRTSP) method is developed for tackling multiple forms of uncertainties
that can be expressed as discrete intervals, probabilistic distributions and/or fuzzy membership functions. The model can
reflect economic penalties of corrective measures against any infeasibilities arising due to a particular realization of system
uncertainties. Moreover, the fuzzy decision space can be delimited into a more robust one with the uncertainties being specified
through dimensional enlargement of the original fuzzy constraints. A management problem in terms of regional air pollution
control has been studied to illustrate the applicability of the proposed approach. Results indicate that useful solutions
for planning the air quality management practices have been generated. They can help decision makers identify desired pollution-abatement
strategy with minimized system cost and maximized environmental efficiency. 相似文献
142.
A geographic information system (GIS)-based approach with spatial analysis advantages was developed to optimize the total
emission control scheme on air pollution in Lanzhou, combined with Models-3 modeling system and a linear programming model.
GIS system is mainly used for establishing a multifactor assessment model to quantitatively divide environmental functional
zone, and also used for selecting control sites in linear programming model. The results show that most of the urban area
belongs to the second type of function, which is 122.8 km2 occupying about 76.5% and the third type of about 32.9 km2 occupying 20.5%. To reach the air quality up to the national standard in the entire control area, some large-emission factories
need to cut emissions from 19% to 27%. For small but low-emission height sources, the cut may be as high 40%. The improvement
of the ecological environment is urgently needed for controlling the background particle pollution in Lanzhou city. 相似文献
143.
Lake eutrophication problems have received considerable attention in Taiwan, especially because they relate to the quality of drinking water. In this study, steady-state river water quality and lake eutrophication models are solved using dynamic programming algorithms to find the nutrient removal rates for eutrophication control during dry season. The kinetic cycle of chlorophyll-a, phosphorus and nitrogen for a complete-mixed lake is considered in the optimization framework. The Newton-iterative technique is adopted to solve the nonlinear equations for the steady-state lake eutrophication model. The optimization framework is applied to Cheng-Ching Lake in southern Taiwan. Several nutrient loading scenarios for eutrophication control are studied. Optimization results for nutrient removal rates and corresponding wastewater treatment capacities of each reach of the Kao-Ping River define the least cost approach to lake eutrophication control. A natural purification method, structural free water surface wetland, is also suggested to save more investment and improve river water quality at the same time. 相似文献
144.
我区环境规划编制与实施现状调查分析 总被引:2,自引:0,他引:2
环境规划是国民经济和社会发展的有机组成部分,是环境决策在时间、空间上的具体安排,其目的是指导人们进行各项环境保护活动,以最小的投资获取最佳的环境效益,促进环境、经济和社会的可持续发展。环境规划担负着从整体上、战略上和统筹规划上来研究和解决环境问题的任务,对于可持续发展战略的顺利实施起着十分重要的作用。 相似文献
145.
本文对建设校园网的前期准备工作作了详细的阐述,对各阶段的工作详细作了规划,对于准备建设校园网的学校具有指导意义. 相似文献
146.
Shuichi Ikebuchi Toshiharu Kojiri 《Journal of the American Water Resources Association》1992,28(1):223-231
ABSTRACT: The operational problems of a reservoir are expressed by three coordinates: space, time stage, and objective. The operational procedure is formulated using dynamic programming as a multi-objective problem. After comparing the scalar and the vector optimization, the scalar optimization technique is applied to turbidity analysis in a reservoir. 相似文献
147.
ABSTRACT: The optimization of real-time operations for a single reservoir system is studied. The objective is to maximize the sum of hourly power generation over a period of one day subject to constraints of hourly power schedules, daily flow requirement for water supply and other purposes, and the limitations of the facilities. The problem has a nonlinear concave objective function with nonlinear concave and linear constraints. Nonlinear Duality Theorems and Lagrangian Procedures are applied to solve the problem where the minimization of the Lagrangian is carried out by a modified gradient projection technique along with an optimal stepsize determination routine. The dimension of the problem in terms of the number of variables and constraints is reduced by eliminating the 24 continuity equations with a special implicit routine. A numerical example is presented using data provided by the Bureau of Reclamation, Sacramento, California. 相似文献
148.
ABSTRACT: The surrogate worth tradeoff method is utilized for evaluation of alternative sewage sludge disposal systems for the Boston, Massachusetts, area. The two objectives incorporated into a decision-making framework are net economic benefit and level of environmental impact. 相似文献
149.
论述通过对脉冲布袋除尘器清灰电磁阀进行分组来降低脉冲布袋除尘器由可编程控制器(PLC)构成控制系统的造价的一种方法. 相似文献
150.
环境规划决策与方法刍议 总被引:1,自引:0,他引:1
介绍了环境规划与决策的基本概念、分类及环境规划决策在国内外的应用.在查阅国内外文献的基础上,提出环境规划决策采用的一般模式、分类以及决策的基本方法.指出在环境规划的具体实务和决策时,可考虑对选择模型的原理和方法的实际运用,并举例说明选择模型在环境规划决策最优方案选择中使用的思路与步骤:通过待选方案的坐标图确定有效率点,连结有效率点确定可能性界限,当有效率点的选择不仅限于一个时,可通过各有效率点的无差异图与可能性界限的切点筛选出最优方案. 相似文献