AQUIFER MANAGEMENT UNDER TRANSIENT AND STEADY-STATE CONDITIONS1

ABSTRACT: The equations of transient and steady-state flow in two-dimensional artesian aquifers are approximated using finite differences. The resulting linear difference equations, combined with other linear physical and management constraints and a linear objective function, comprise a linear programming (LP) formulation. Solutions of such LP models are used to determine optimal well distributions and pumping rates to meet given management objectives for a hypothetical transient problem and for a steady-state field problem.     

Landfill space consumption dynamics in the Lower Rio Grande Valley by grey integer programming-based games

The Lower Rio Grande Valley (LRGV) region in South Texas emerges as a warehouse and transportation center between Central America and the US with positive growth impacts due to the North American Free Trade Agreement (NAFTA). In 10 years time, a 39.8% population increase has resulted in a 25% boost in solid waste per capita disposal rate in the region. A landfill space shortage drives a need for landfill operators to understand their optimal management strategies in this highly-competitive market. Initially, a strategic plan for optimal solid waste pattern distribution minimizes net costs for cities. This is accomplished through a grey integer programming algorithm that encapsulates all uncertainty present in the solid waste system. Secondly, a series of grey integer submodels construct payoff matrices for a zero-sum two-person game. The ensuing game theoretic analysis is critical for evaluating optimal pricing strategies for tipping fees available to the most significant regional landfills (e.g. Browning-Ferris Industries (BFI) and City of Edinburg) as they compete over disposal contracts. The BFI landfill intrinsically benefits from its competitive pricing policy and central location to solid waste generators. The City of Edinburg landfill, on the other hand, wishes to secure its lucrative solid waste management revenue. It desires a gaming strategy backed by optimality that integrates ambiguity in solid waste generation, design capacity boundaries, and unitary shipping costs. Results show that a two-tiered analysis via grey integer programming-based games may pave the way for 'grey Nash equilibria' pricing tactics that will help the Edinburg landfill maintain its waste contracts.     

COST EFFECTIVE OPERATION OF URBAN WATER SUPPLY SYSTEM USING DYNAMIC PROGRAMMING1

ABSTRACT: Efficient operation of a city water supply system is an important goal of all municipalities. Efficient operation should result in minimum operation cost through reduction in total energy use and/ or reduction in on-peak energy consumption. An optimization model was designed for operating the water supply systems of cities using groundwater. The Newton-Raphson pipe network was used for network analysis and a dynamic programming optimization algorithm was used for determining a schedule for pump operation in the pipe network system. The model is most suitable for use in small cities with up to 45,000 in population, but with large-scale disintegration techniques may also be used for larger cities. The savings in operation costs are a function of energy cost and energy use pattern and water use pattern in the area.     

LINEAR PROGRAMS FOR NONLINEAR HYDROLOGIC ESTIMATION1

ABSTRACT: The minimization of the sum of absolute deviations and the minimization of the absolute maximum deviation (mini-max) were transformed into equivalent linear programs for the estimation of parameters in a transient and linear hydrologic system. It is demonstrated that these two methods yield viable parameter estimates that are globally optimal and reproduce properly the timing and magnitude of hydrologic events and associated variables such as total runoff. The two linear estimation methods compared favorably with the popular least-squares nonlinear estimation method. The generality of the theoretical developments shows that linear program equivalents are adequate competitors of nonlinear methods of hydrologic estimation and parameter calibration.     

伊金霍洛旗生态环境建设与对策分析

生态环境是人类生存和发展的基本条件。保护和建设好生态环境，是实现经济社会可持续发展的迫切要求，也是一个地区可持续发展的重要内容。文章从伊金霍洛旗实际出发。以生态效益、经济效益、社会效益有序配置和高度统一，统筹考虑生态环境与经济社会的发展。并提出了有效的建设和保护措施。     

建筑施工现场危险区域主客观双线路风险评估研究

危险源是危险区域分析的基础,在国家强调工业安全的背景下,建筑工程施工现场危险区域的安全管理显得尤为重要,但目前相关领域缺乏系统的识别方法与评估框架.在考虑危险区域的阶段性与空间性的基础上,将主客观双线路评估应用于建筑施工现场危险区域的风险评估.主观路线采用失效模式与影响分析(FMEA)方法实施,并利用综合加权模糊TOP...     

基于不确定性的水资源优化配置模型及其实证研究

针对城市水资源系统中存在的不确定性,将可信性模糊机会约束规划模型与区间规划相结合,提出了不确定环境下的可信性模糊-区间线性规划(FILP)模型,将其应用于某城市水资源优化配置与科学管理中,构建了城市水资源优化配置FILP模型.该模型以城市的经济、社会与环境的可持续发展为目标,以供需水量等为不确定性约束,以各水源在各子区不同部门间的分配为决策变量,利用改进的风险显性区间规划算法进行求解得到一定置信度和意愿水平下的水资源优化配置风险-收益权衡方案.实证研究表明,该模型反映了不确定性因素对水资源系统收益的影响,能够为实际的优化决策提供方法支持.     

循环经济评价指标体系进展研究

发展循环经济是实现可持续发展的新经济模式,也是全面建设小康社会的必然选择.本文在分析了我国循环经济的内涵和衡量标准的基础上,详细介绍了现有我国循环经济评价指标体系在社会、区域和企业三个层面的研究状况,并归纳、总结了我国循环经济评价指标体系研究中存在的一些问题,提出今后的研究重点:(1)以不同的理论为基础,分别建立社会、区域和企业的评价指标体系.(2)通过建立综合评价模型等方法进行循环经济的总体评价.(3)加强对指标权重的研究.(4)加强对具体企业循环经济评价指标体系的研究.     

基于DPSIR模型的省域绿色发展绩效评价

提高绿色发展水平是推动生态文明建设,实现美丽中国的重要途径。将驱动力—压力—状态—影响—响应（DPSIR）模型运用在绿色发展绩效评价中,构建了建设美丽中国愿景下的省域绿色发展绩效评价指标体系,采用层次分析法确定指标权重,采取目标渐进法进行标准化处理,在此基础上构建省域绿色发展绩效综合指数。以贵州省为研究对象,对2009—2019年的绿色发展水平进行评估。结果表明：2009—2019年贵州省绿色发展绩效综合指数呈逐年递增,从Ⅰ级（低）向Ⅲ级（一般）转化的趋势;DPSIR模型中压力层的社会压力、资源消耗、污染排放指标对贵州省绿色发展影响最大;目前贵州省绿色发展处于一般水平（Ⅲ级）,下一阶段应重视提升经济发展水平、实施生态环境整治、推进减污降碳、加大民生保障等方面,从而提高贵州省绿色发展水平,最终实现“美丽贵州”。

     

实施ISO14000系列标准应与我国实际相结合

简要介绍ＩＳＯ１４０００系列标准的特点，内容和目的，一年多试点工作表明实施ＩＳＯ１４０００环境管理系列标准将成为环境管理模式的一次重大发展，从６个方面阐述了实施ＩＳＯ１４０００系列标准必须与我国的环境保护工作实际尤其应与正在推行的清洁生产相结合。