低湖平原典型湖垸水系规划数学模型——新兴垸排涝灌溉系统最优规划

以“四湖”地区典型湖垸（新兴垸）为背景，给出了典型湖垸水利系统满足综合设计排涝标准的评价准则。用大系统理论与方法，建立了该湖垸水利规划的大系统数学模型，提出了根据子系统之间的关联变量修建节制闸的设计思想，从而使排涝灌溉一体化。最后，用动态规划方法，给出了递推关系式。     

基于双层规划模型的城市固体废物管理系统优化研究

采用变权重组合模型和情景分析法,对北京市的城市固体废物(MSW)产量进行有效地预测.预测结果表明,北京市垃圾产量增幅不大但处理设施容量存在缺口.在科学预测的基础上,构建以温室气体(GHG)控制为上层目标,系统成本最小化为下层目标的双层规划模型(BLPMGMC).该模型的结果表明,焚烧和堆肥将是北京市MSW的主要处理方式;在3个规划时段内,GHG总排放量达到1.67×106t(以CO2当量计),填埋场的CH4和焚烧厂的N2O是GHG排放的主要贡献者;系统总成本达到7.0×109元,其中,65%的成本来自于焚烧厂和堆肥厂.4种模型结果的对比分析表明,双层规划能提供综合经济和环境因素的管理方案.     

危险品运输道路轴辐式网络设计

为降低危险品运输网络的总风险和成本,实现规模效益,根据危险品道路运输网络规划中存在监管者路网规划和运输者路线选择的双层约束特征,探讨轴辐式网络在危险品运输网络设计中的应用。针对长距离、大规模的第三方危险品货运业务,建立上层以风险最小化,下层以成本最小化为目标的双层规划模型。运用Matlab对模型进行求解。最后,通过实例分析检验模型和算法的有效性。结果表明,通过对运输企业网络进行轴辐式网络设计,即将原有节点设置为一个或多个枢纽点,集中零散分布的货源,能比传统直通式物流网络设计节约总运输成本。     

IDENTIFICATION OF AN OPTIMAL GROUNDWATER MANAGEMENT STRATEGY IN A CONTAMINATED AQUIFER1

A groundwater hydraulic management model is used to identify the optimal strategy for allocating limited fresh-water supplies and containing wastes in a hypothetical aquifer affected by brine contamination from surface disposal ponds. The present cost of pumping from a network of potential supply and interception wells is minimized over a five-year planning period, subject to a set of hydraulic, institutional, and legal constraints. Hydraulic constraints are formulated using linear systems theory to describe drawdown and velocity variables as linear functions of supply and interception well discharge decision variables. Successful validation of the optimal management strategy suggests that the model formulation can feasibly be applied to define management options for locally contaminated aquifer systems which are used to fulfill fresh-water demands.     

ASSESSMENT ANALYSIS FOR WATER SUPPLY ALTERNATIVES1

ABSTRACT Providing adequate water supplies of good quality is becoming a serious problem in many areas of the United States. Some of the alternatives proposed for meeting the growing shortage of clean-water or cheap-water are reallocation, reuse, and importation. This paper outlines a methodology to assess all of these water supply alternatives by examining the amount and time-staging for development of water sources. In conceptualizing the problem, sources of supply are classified in three categories: primary or base supplies, secondary or effluent supplies, and supplementary or imported supplies. A model of the water system is formulated as a “transportation problem” in linear programming depicting the possible sources of supply which can be used to satisfy the requirements of various water users. The optimizing objective in the model is to minimize the cost of water under various assumptions for operating the system. A case study of the Salt Lake Qty, Utah, area is used to illustrate the application of the model in obtaining optimal water supply allocations for projected future demands. Assessment of alternatives in the study include redistribution of supplies, time-staging of supplies and related treatment facilities, and sensitivity of allocations to changes in costs.     

Waterfowls habitat modeling: Simulation of nest site selection for the migratory Little Tern (Sterna albifrons) in the Nakdong estuary

This paper aims to find patterns in nest site selection by Little Terns Sterna albifrons, in the Nakdong estuary in South Korea. This estuary is important waterfowl stopover and breeding habitat, located in the middle of the East Asia-Australasian Flyway. The Little Tern is a common species easily observed near the seashore but their number is gradually declining around the world. We investigated their nests and eggs on a barrier islet in the Nakdong estuary during the breeding season (May to June, 2007), and a pattern for the nest site selection was identified using genetic programming (GP). The GP generated a predictive rule-set model for the number of Little Tern nests (training: R² = 0.48 and test: 0.46). The physical features of average elevation, variation of elevation, plant coverage, and average plant height were estimated to determine the influence on nest numbers for Little Tern. A series of sensitivity analyses stressed that mean elevation and vegetation played an important role in nest distribution for Little Tern. The influence of these two variables could be maximized when elevation changed moderately within the sampled quadrats. The study results are regarded as a good example of applying GP to vertebrate distribution patterning and prediction with several important advantages compared to conventional modeling techniques, and can help establish a management or restoration strategy for the species.     

Parameter Uncertainty Reduction for SWAT Using Grace,Streamflow, and Groundwater Table Data for Lower Missouri River Basin1

Abstract: This study incorporates the newly available Gravity Recovery and Climate Experiment (GRACE) water storage data and water table data from well logs to reduce parameter uncertainty in Soil and Water Assessment Tool (SWAT) calibration using a SUFI2 (sequential uncertainty fitting) framework for the Lower Missouri River Basin. Model evaluations are performed in multiple stages using a multiobjective function consisting of multisite streamflow and GRACE water storage data as well as a groundwater component. Results show that (1) a model calibrated with both streamflow and GRACE data simultaneously can maintain the water balance for the whole basin, but may improperly partition surface flow and base flow. Additional inclusion of the groundwater constraint can significantly improve the model performance in groundwater hydrological processes. In our case, the estimation of specific yield of shallow aquifers has been increased to 10^?2 from previous much underestimated level (<10^?3). (2) The daily streamflow data are needed to confine the parameters related to water flow in channels such as the Manning’s coefficient, which are less sensitive to the monthly simulations. (3) Parameters are nonuniformly sensitive for different goal variables, and thus, proper specification of a prior distribution of parameters may be the key factor for global optimization algorithms to obtain stable and realistic model performance.     

Sustainability of forest management plans: a discrete goal programming approach

Let us consider i = 1, 2,...n alternative forest plans to be evaluated according to j = 1, 2,...m indicators of sustainability. An expert or panel of experts suggests a set of targets or desirable levels of achievement for the m indicators of sustainability considered. Within this context, an important problem is to determine the system with a higher level of achievement with respect to the targets attached by the expert to the m indicators. A natural extension of this problem involves determining a ranking of the n systems considered. A general procedure based on discrete goal programming is proposed to address these problems. The methodology is applied in a case study of a Spanish forest.     

生态工业园区建设理论探讨

资源和环境问题是我国面临的严重的生态安全和环境安全问题 ,也是制约我国经济可持续发展的问题。生态工业是与环境协调发展的环境友好的工业体系。生态工业园是实现生态工业的理想的生态系统 ,通过工业园区内物质流、能量流、信息流和正确设计来模拟自然生态系统 ,形成企业间的共生网络 ,从而解决工业发展与资源和环境保护之间的相互制约的关系。随着我国工业化进程的推进 ,生态工业园区的建设步伐也在加快。笔者对生态工业园区建设的总体思路、建设指标以及建设过程中存在的主要问题等内容进行了理论探讨。以期抛砖引玉 ,促进生态工业园区的理论研究 ,推动生态工业园区在我国的实践。     

COMPROMISE PROGRAMMING METHODOLOGY FOR DETERMINING INSTREAM FLOW UNDER MULTIOBJECTIVE WATER ALLOCATION CRITERIA1

ABSTRACT: This paper presents a quantitative assessment framework for determining the instream flow under multiobjective water allocation criteria. The Range of Variability Approach (RVA) is employed to evaluate the hydrologic alterations caused by flow diversions, and the resulting degrees of alteration for the 32 Indicators of Hydrologic Alteration (IHAs) are integrated as an overall degree of hydrologic alteration. By including this index in the objective function, it is possible to optimize the water allocation scheme using compromise programming to minimize the hydrologic alteration and water supply shortages. The proposed methodology is applied to a case study of the Kaoping diversion weir in Taiwan. The results indicate that the current release of 9.5 m³/s as a minimum instream flow does not effectively mitigate the highly altered hydrologic regime. Increasing the instream flow would reduce the overall degree of hydrologic alteration; however, this is achieved at the cost of increasing the water supply shortages. The effects on the optimal instream flow of the weighting factors assigned to water supplies and natural flow variations are also investigated. With equal weighting assigned to the multiple objectives, the optimal instream flow of 26 m³/s leads to a less severely altered hydrologic regime, especially for those low‐flow characteristics, thereby providing a better protection of the riverine environment.