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651.
环境质量评价模糊集理论与模式研究 总被引:5,自引:0,他引:5
探讨了模糊集理论方法对环境质量评价的可行性,以大气环境质量评价为例,叙述了这种方法的研究程序及计算步骤。研究表明,采用模糊集理论方法对大气环境质量进行评价,结果结果合理,方法可行,有一定的参考价值。 相似文献
652.
Targeting Water Reuse with Multiple Contaminants 总被引:1,自引:0,他引:1
653.
我国钢铁工业废水治理及其发展趋势 总被引:1,自引:0,他引:1
我国水资源人均拥有量仅为世界人均拥有量的四分之一,而且降水在时空分布上很不均衡。这一现实,决定了节省水资源,保护水环境是我国一项长期的战略任务。文章概要地叙述了钢铁工业废水治理及其发展过程。作者认为,要从根本上解决钢铁工业废水对水环境的污染与破坏,必须采取综合防治措施,并把整套循环用水技术引入生产工艺过程,使废水与污染物都作为资源加以回收,并实现循环利用。上述过程的实质,是模拟大自然生物圈循环运行 相似文献
654.
John W. Labadie Dennis A. Bode Andrew M. Pineda 《Journal of the American Water Resources Association》1986,22(6):927-940
ABSTRACT: A water supply network optimization model called MODSIM3 is presented as a decision-support tool for aiding city staff in determining how best to utilize and exchange existing and potential water supplies with other users in a river basin. The model is applied to the City of Fort Collins, Colorado, water supply system as a means of determining optimum ways the City can utilize direct flow rights, storage rights, and exchangeable waters from various sources. Results clearly confirm both the benefits of the use of exchanges and the value of MODSIM3 as a water supply planning and management tool. 相似文献
655.
M. Heidari J. Sadeghipour O. Drici 《Journal of the American Water Resources Association》1987,23(2):325-335
ABSTRACT: A ground-water-management model was developed to investigate the best management options for the containment of an oil-field-brine plume in the Equus Beds aquifer in south-central Kansas. The main purpose of the management model was to find the optimal locations and minimum rates of pumpage of a set of plume-interception wells, to successfully reverse the velocity vectors at observation wells located along the plume front, and also to satisfy freshwater demands from supply wells. The effects of the calculated minimum withdrawals from the interception wells on the migration of contaminants throughout the ground-water system were evaluated utilizing a solute-transport model. This latter analysis was carried out to ensure the containment of the plume. Whereas application of the management model to the study area achieves the management objectives, the implementation of the results is believed to be impractical and expensive. This is because a considerable amount of water must be pumped out to reverse the velocity vectors in the vicinity of the plume. In general, the proposed technique of pollutant containment may be effective when applied to aquifers having low hydraulic gradients and/or to aquifers with hazardous plumes whose containment is not subject to economic constraints. 相似文献
656.
Wulf Lindner Klaus Lindner Gabor Karadi 《Journal of the American Water Resources Association》1988,24(1):27-33
ABSTRACT; This paper presents a numerical model for the prediction of optimal ground water withdrawal from a two-aquifer system by observing a set of constraints determined by the ecological conditions of the ground water basin. The aquifer system consists of an upper unconfined and a lower confined aquifer with a leaky stratum between them. It is assumed that water is withdrawn from the confined aquifer only, but the unconfined aquifer will also be affected due to the leakiness of the layer separating the upper and lower aquifers. Simulation and linear programming are employed for developing a computer model for the optimal management of such systems, with the objectives of determining withdrawal rates for predetermined ground water levels. 相似文献
657.
J. Hugh. Ellis Charles S. ReVelle 《Journal of the American Water Resources Association》1988,24(2):435-447
ABSTRACT: A deterministic, separable, linear algorithm is presented for maximizing aggregate hydropower production. The method is iterative and amenable to solution using standard LP software. The utility of the technique is demonstrated using several test applications involving a hypothetical single-purpose hydropower reservoir and a monthly increment 20-year flow record from the Gunpowder River in Maryland. The separable linearized forms solved quickly using MPSX on a variety of IBM hardware: 3090-400 VF, 3084 QX, dual processor 4381-3, and an AT/370 personal computer. For comparison purposes, the original nonlinear nonseparable version of the model was also solved using MINOS. This yielded a value of aggregate hydropower marginally higher than that using MPSX. The separable, linearized methodology proved to be a useful and an efficient means of generating good starting points for MINOS. The use of these warm starts effected substantial reductions in MINOS execution times. 相似文献
658.
Spatial based compromise programming for multiple criteria decision making in land use planning 总被引:1,自引:0,他引:1
Sumbangan Baja David M. Chapman Deirdre Dragovich 《Environmental Modeling and Assessment》2007,12(3):171-184
Today, competing land use is continuing to occur in many developed regions. In the Agricultural Development Zone of Western
Sydney Region, which is characterised by complex landscape patterns, land use competition is widespread. From a land use planning
perspective, identification of suitable locations for a given type of land use is necessary for decision makers to formulate
land use alternatives in different locations, based on existing land potential and constraints. For such a region, use of
a simple method that implements a categorical system and considers only inherent land characteristics in the analysis is often
inadequate to arrive at an optimal spatial decision. The primary aim of this paper is to develop spatial modelling procedures
for agricultural land suitability analysis using compromise programming (CoPr) and fuzzy set approach within a geographical
information systems (GIS) environment. Five main sets of spatial data for use as decision criteria were developed by using
fuzzy set methodology: a land suitability index (LSI) for maximising the land productivity objective; an erosion tolerance
index (ETI) for minimising the erosion risk objective; a runoff curve number (CN) for maximising the water discharge regulation
objective; an accessibility (RP) measure for maximising the land accessibility objective; and the proximity to water body
(WP) for minimising the water pollution objective. An L
p
-metric was used in the analysis utilising different strategies with representative indices ranging from a situation where
full tradeoff among criteria occurs to a noncompensatory condition. Different weighting combinations were also applied, and decision analysis was carried out by using values ranging
from 0 to 1.0, where 1.0 is considered as an ideal point. The CoPr model demonstrated in this paper yielded a promising result,
as several different techniques of sensitivity analysis show reasonably good results. Likewise, an overlay of that result
with the present land use/land cover indicates a good corresponding spatial matching between existing land use (orchard and
cultivated land), and the cells (land parcels) classified as the best in CoPr. The results are amenable to various map display
techniques, either using continuous values or by defining different cut off points in the data space within a raster GIS environment. 相似文献
659.
660.
济南地下水资源系统多目标管理模型及模糊带权方法 总被引:1,自引:0,他引:1
根据济南地下水资源系统管理研究,建立了济南地下水资源系统多目标管理模型;利用模糊数学理论,提出一种模糊带权方法,它能同时解决互为矛盾、互为竞争的各目标之间的不可比性和主次性问题。实际计算表明,本文建立的多目标管理模型和提出的方法是合理的和有效的。 相似文献