长江,嘉陵江重庆城区段二维水质对流扩散数学模型

对二水质对流扩散数学模型的有限差分解作了较详细的叙述，同时对距离步长，时间步长计算，网络内水深，流速，横向扩散系数的求取也作了简要介绍。     

咸淡水地区种植结构优化模型

本文将地下水系统控制与作物种植系统相结合,建立以浅层地下水投入效益为目标,在水土资源等多种约束条件下咸淡水地区种植结构优化模型。该模型被用于确定河北省南皮县几个典型年份(1985,1990,1995,2000)种植结构优化方案。     

冷轧带钢在线磨辊辊面粗糙度的实验研究

对影响磨削辊面粗糙度的因素进行了系统分析和实验研究 ,得出了轧辊转速、砂轮速度、砂轮粒度、磨削液等因素对磨削辊面粗糙度影响的一般规律 ,利用回归分析的方法建立了粗糙度的数学模型     

人工神经网络模型和公路复垦土地适宜性评价

提出了人工神经网络用于公路临时用地复垦土地适宜性评价，利用该模型对京大高速公路山西段复垦山西段复垦土地进行了适宜性评价，探讨了人工神经网络在土地复垦适宜性评价时的特点和注意问题。     

灰色局势决策模型在生态环境综合整治方案优化中的应用

应用灰色系统理论，将安徽省环境问题归纳为１０类事件，针对这些事件提出 对策，建立灰色局势决策模型，得到了符合安徽省社会、经济、技术及环境条件的优化决策方案。研究表明，灰色局势决策模型原理简单，计算简便，结果可靠，是玫中很实用价值的多方案优化模型。     

三维叠前时间偏移技术在江苏WZD地区的应用

当地下地质构造复杂、断裂发育,横向速度变化不是太剧烈的情况下,提高偏移成像精度,三维叠前时间偏移是一种行之有效的方法。三维叠前时间偏移取得成功的关键:一是高保真、高信噪比的叠前数据;二是建立一个合理的三维偏移速度场。随着计算机性能的不断提高,三维叠前时间偏移逐渐成为常规处理技术,该技术在江苏油田WZD地区得到了广泛的应用,实际资料处理结果及钻探效果证实了三维叠前时间偏移技术是解决WZD地区复杂构造成像精度的一种好方法。     

昆明的水资源及其开发

昆明地区地面水紧缺，地下水资源虽然丰富，但部分富水地段过量开采，已形成严重后果。目前除从流域内水库开发外，规划从牛栏江、普渡河引水，满足近、中期需要。至２０１０年，昆明供水预计出现２８０×１０６ｍ３／ａ的缺口，必须制订相应政策，采取控制和治理滇池污染等措施，才能缓解矛盾，保证经济的可持续发展。     

Heavy metal adsorption on the Le An River sediment —The adsorption model

In this study,the surface properties and adsorption properties of the Le An River sediment were modelled via surface complexation approach.The model parameters were determined based on the data of our potentiometric titration experiments and the metal adsorption experiments with the Le An River sediment samples.Consequently,the surface complexation models for the natural sediment,in our case the Le An River sediments,which can interpret the experimental data very well were successfully established.Three typical surface complexation models that is the constant capacitance model,the diffuse layer model and the triple layer model,were considered in this research.This work indicated that the consistency and the interdependency among model parameters together with the selection of the surface adsorbed species should be emphasized.     

Effect of domestic sewage on growth of phytoplankton-mathematical model

A mathematical model relating to the change in phytoplankton biomass in the period of growth and nutrient concentration in the media was proposed on the basis of the Monod equation and was testified by simulation experiments. Analysis of the experiment data showed that: the half-saturation constants for growth Kp (μmol/L) for Skeletonema, Chaetoceros and Prorocentrum were 5.52, 1.90 and 0.46, respectively; the balance between stimulation of nutrients and the inhibition of some other materials was found in the effect of domestic sewage on algal growth and the stimulation played a leading role; domestic sewage was more stimulative on dinoflag-ellate than on diatom and chlorophyte when the assemblage of the algae was cultured. The experiment suggested that mathematical model reasonably explained the characteristics of phytoplankton growth in different nutrient conditions and was worthy to be further improved for eutrophication prediction in off-shore water.     

宁夏人口、粮食与水土资源利用

人口、粮食与水土资源利用是宁夏回族自治区国民经济发展中的重要问题。文中分析了宁夏人口、粮食与水土资源利用现状,应用灰色系统理论及回归分析,建立人口、粮食预测模型,对2000年宁夏的人口、粮食进行了预测。分析2000年水土资源不同开发利用条件下粮食供需平衡情况后指出,充分合理利用黄河水资源,扩大灌溉面积,配合先进的农业技术,宁夏粮食不仅能自给,而且还能提供一定数量的商品粮。最后提出了解决粮食问题,防止生态环境恶化的主要途径。