Environmentally conscious long-range planning and design of supply chain networks

In this paper, a mathematical programming-based methodology is presented for the explicit inclusion of life cycle assessment (LCA) criteria as part of the strategic investment decisions related to the design and planning of supply chain networks. By considering the multiple environmental concerns together with the traditional economic criteria, the planning task is formulated as a multi-objective optimization problem. Over a long-range planning horizon, the methodology utilizes mixed integer modelling techniques to address strategic decisions involving the selection, allocation and capacity expansion of processing technologies and assignment of transportation links required to satisfy the demands at the markets. At the operational level, optimal production profiles and flows of material between various components within the supply chain are determined. As such, the formulation presented here combines the elements of the classical plant location and capacity expansion problems with the principles of LCA to develop a quantitative decision-support tool for environmentally conscious strategic investment planning.     

Model-based direct search optimization of the broke recirculation system in a newsprint mill

This work is concerned with the dynamic modelling of the papermaking section of an integrated newsprint mill, and the subsequent application of two direct search methods in a proof-of-concept optimization study of broke recirculation strategies. The effect of the current broke recirculation policy on the mixed pulp properties at the paper machine headboxes was quantified using a dynamic simulation generating data for an objective function which reflected the rate of change in measurable (flow, consistency and temperature) and immeasurable (total dissolved solids and fibre length distribution) parameters. Genetic Algorithm and the Nelder–Mead simplex methods were then linked dynamically to the simulation and used to find improved ways of recirculating broke pulp. Specifically, the profile of the changes to the broke ratio was modelled using a quadratic function and a second-order transfer function, and the coefficients of these functions were optimized. The optimized broke recirculation resulted in a significant reduction in the value of the objective function, thus, suggesting that the fluctuations in the properties of the mixed pulp stream could be dampened and paper machine headbox stability improved. It is expected that this process enhancement strategy would contribute to an increase in production yield (via a reduction in the occurrence of paper machine breaks), and thus an overall reduction in the waste of materials and energy.     

一维非稳态河流水质模型的一种数值解法

根据实际情况需要，讨论了一维河流在非稳态条件下难于解析法求解时的一种数值法－隐式差分法，在此基础上，为了对实际工作中相应河流模式计算提供借鉴和参考。应用微机对这种方法进行了模拟计算和结果分析。     

金属塑性成形计算机模拟的若干进展

结合作者正在开展的研究工作，综述了金属生性成形计算机模拟技术近年来的一些重要进展，主要涉及模拟计算方法，利用模拟技术的工艺优化设计、材料组织性能演化的模拟以及模拟软件设计方法等。     

宁镇山脉岩基岩浆的化学演化

本文根据四个杂岩体中主要矿物的化学成分和全岩主要元素资料,利用T·L·Wright(1984)提供的质量平衡计算程序来模拟它们的成因,然后再用微量元素来检验和完善上述模式。定量模拟结果表明,分离结晶作用是造成这些杂岩体在岩石学和地球化学上分异的主要原因,并可用斜长石,角闪石、黑云母、磷灰石和榍石的分步分离来解释各杂岩体的成分变化,但对每一个杂岩体来说矿物分离比例可大不相同。微量元素的检验结果和主要元素的模拟趋势基本一致,但分离矿物的绝对值可不完全相同。     

基于PFEA法的板料成形工艺参数优化

基于参数化有限元分析(PFEA)法,对板料成形工艺参数优化进行了深入的研究,利用交互式参数化有限元分析方法对典型的方盒件工艺参数进行了优化研究,其优化结果与试验结果基本吻合,表明优化方案高效、可行。     

洱海流域环境经济相协调的农林土地利用不确定性系统规划

以云南大理洱海流域为例，应用区间数量优化模型对流域的农林土地利用进行了研究．结果表明，洱海流域目前的土地利用结构需要进行适当调整，具体调整方案因分区不同而不同．决策者可以在模型解的基础上，结合经验和系统新信息对模型解作进一步解译以生成合理可行的实施方案，确保在适当的非点源污染贡献的范围内土地利用的经济产出最大，从而达到流域农林土地利用的环境经济协调发展     

密切值法用于城市污水处理厂布局规划的研究

用密切值法作多目标决策优选，由城市污水处理厂的3个标准方式和11个家处理厂的工艺改造投资、污水厂运行成本和处理水量等11个评价指标的极端情况，组成“虚拟”的最好（长期保留）和最差（应该废除）方案，进而求出各污水处理厂（统称为样本点）与最好、最差方案的距离，计算可综合反映与最好和最差方案距离两者水平的综合参数－密切值，并根据密切值的大小进行排序。实例计算表明，密切值法与灰色局势决策法得到相似的排序结果，说明密切值法用于城市污水处理厂布局规划是切实可行的。而且密切值法不需要确定白化函数等主观参数，计算结果更客观和可靠。     

浅谈排污指标有偿转让

实行排污权交易，将企业经济效益同污染防治工作直接挂钩，可变企业被动防治污染为主动防治，变政府直接管理环境为间接管理，更符合社会主义市场经济运行机制。排污指标有偿使用与转让是排污权交易的核心，着重探讨了排污指标有偿使用费与有偿转让费的计算及排污指标交易中的注意事项。     

BOD5测定的简捷方法研究

目前国内外普遍规定20±1℃培养5天,分别测定样品培养前后的溶解氧(简称DO),二者之差即为BOD5值.对同一水样,只测出培养前的任一稀释倍数水样的DO值,通过计算便可准确得出其它稀释倍数水样的D0值.通过对不同浓度下BOD5实测值与计算值进行比较,计算出相对误差进行分析,结果都达到了水质监测实验室质量控制指标-准确度允许差.因此,这种计算方法是切实可行.