地表水多级模糊数学评价法修正应用探讨

针对地表水水质状况的科学评价问题,从计算原理出发,深入分析多级模糊数学综合评价方法无法科学合理评价劣Ⅴ类地表水的根本原因,并在此基础上探索性提出模糊数学评价应用修正方案。以武汉市的4个典型湖泊为评价分析对象,对修正方案的评估结果进行比较。实例研究证实模糊数学评价修正法能科学识别和合理描述劣V类水体的水质污染状况。以所有地表水污染状况为基础,整合所有待评水体污染指标超标最大值体系(溶解氧浓度的最小值)作为劣V类水质统一标准限值,能有效提高该评价法的科学合理性及全面通用性,有助于模糊数学综合评价法在地表水水质评价领域应用的完善与推广。     

模糊数学在水质综合评价中的应用

水质评价是环境管理的一个重要方面。污染程度是一个模糊概念，在实际工作把离散的质量级别进行连续性处理。模糊数学在水质评价中得到广泛应用。以长江干流段2004年1月至2004年12月的水质监测资料作为依据，运用模糊综合评价方法对水质进行了分级评价。结果显示，所评价的长江干流段水质为地表水标准中的Ⅱ类水。在2004年1月至2004年12月的时间段内，长江水质综合指数在2．0至2．6之间变动，2004年2月和8月水质综合指数最多为2．6，水质随时间的变化较平缓。在所评价的长江5个断面中水质综合指数都小于3．0，其中湖南岳阳城陵矶水质综合指数最高为2．6，其主要的污染物为CODMn，江苏南京林山水质综合指数最小为2．0。     

Modelling and optimisation of a product recovery network

An appropriate logistics network is an important element of the infrastructure of any product recovery company. Small and medium enterprises (SMEs) constitute a major fraction of the product recovery industry with a different business objective and scale of operation from those of original equipment manufacturers. This paper addresses the network design issues for SMEs involved in product recovery activities. A mathematical formulation is presented in an SME context and a subsequent simulation model is developed. A genetic algorithm approach is presented for optimising the network for a single product scenario.     

Construction of an optimum system design method considering product lifecycle

This paper proposes an optimum system design method that especially considers product lifecycles and aims to help designers make effective decisions during the product design phase. By considering and estimating all lifecycle factors of cost and environmental impact in addition to the product performance, this method facilitates development of optimum design solutions that incorporate requirements pertaining to the product's entire lifecycle. Furthermore, quantitative estimation of lifecycle factors enables the numerical expression of optimum solutions, rather than depending primarily on experiment and designer intuition. To demonstrate the effectiveness of the proposed method, this paper develops an optimum system design method for a milling machine as an example of a machine product designed for long term use. The lifecycle cost and the lifecycle environmental impact are generally expressed as the summation of each value during manufacturing phase, usage phase, disposal phase and recycling phase. In this example model, Eco-indicator 99 is used to evaluate environmental impact. In the proposed lifecycle design optimisation method, the relationships among the product performance, the lifecycle cost and the lifecycle environmental impact are evaluated as a multi-objective optimisation problem. Analysis of the obtained Pareto optimum solution sets subsequently enables designers to pursue breakthrough product design solutions.     

Sustainable supply chain network design: a multicriteria perspective

In this paper, we develop a rigorous modelling and analytical framework for the design of sustainable supply chain networks. We consider a firm that is engaged in determining the capacities of its various supply chain activities, i.e. the manufacturing, storage and distribution of the product to the demand locations. The firm is faced with both capital costs associated with constructing the link capacities and the links' operational costs. Moreover, the firm is aware of the emissions generated associated with the alternative manufacturing plants, storage facilities and modes of transportation/shipment, which may have different levels of emissions due, for example, to distinct technologies of, respectively, production, storage and transportation. The firm is assumed to be a multicriteria decision-maker who seeks to not only minimise the total costs associated with design/construction and operation, but also to minimise the emissions generated, with an appropriate weight, which reflects the price of the emissions, associated with the various supply chain network activities. We provide both the network optimisation modelling framework and an algorithm, which is then applied to compute solutions to a spectrum of numerical sustainable supply chain design examples in order to illustrate our approach.     

大城市郊区土地利用结构类型区评价：以南京市为例

通过对南京市郊区土地利用结构类型区划分指标的模糊聚类分析，将南京城郊划分为８个类型区，并比较分析了各个类型区的土地利用特征及集约经营程度，土地利用效益，最后指出：为了优化配置郊区土地资源，南京市郊区土地利用必须采取因地制宜，综合利用，集约经营，增加投入，保护耕地，持续利用的措施。     

Optimisation of reduction of global CO2 emission based on a simple model of the carbon cycle

A simple model has been designed to describe the interaction of climate and biosphere. Carbon dioxide, understood as a major emitted gas, leads to a change of global climate. Economic interpretation of the model is based on the maximisation of the global CO₂ cumulative emissions. The two most important profiles of emission have been obtained: optimal and multi-exponential suboptimal profiles, each displaying different characteristics. This revised version was published online in July 2006 with corrections to the Cover Date.     

单要素环境质量评价数学模式分析与探讨

本文以沈阳市地下水环境质量评价为例,在对综合指数法和模糊综合评判法进行理论阐述和模式分析的基础上,探讨两种方法的理论和实用价值及存在问题.