对结构静力弹塑性分析方法的几点改进

探讨了结构静力弹塑性分析方法的基本原理，指出了该方法目前存在的缺陷，基于模态Pushover法（MPA）提出了根据振型参与重量来确定对结构地震反应起主要影响的振型数以及两阶段的侧向力加载模式，并对确定结构目标位移的方法作了一些改进。采用动力时程分析法和改进的静力弹塑性方法，对一个优化钢框架结构的地震反应进行了数值模拟分析，其结果表明，采用本文改进的静力弹塑性分析方法对结构进行推覆分析，能较准确地模拟结构的地震反应，具有易操作、计算精度高的优点。     

Structural analysis of assemblages of thin-walled members

A matrix method for the analysis of structural systems composed of thin-walled members is presented. The matrix displacement analysis includes the effects of thin-walled non-uniform torsion theory, cross-section asymmetry, eccentric restraint as well as joint types peculiar to thin-walled members. The method is used for a prediction of the elastic behaviour of a set of representative test frames. The test frames were pitched-roof portals constructed from channel sections bent about their major-axis and supported by eccentric restraints simulating purlins and girts.     

灰色神经网络最优权组合模型预测城市需水量

需水量预测是一个大量数据指标和影响因素共同作用的复杂系统。目前以单一的模型预测为主,而这种预测方法仅能体现该系统的局部。针对这一情况,利用灰色模型和改进BP神经网络,建立最优权组合模型预测城市需水量,使用Matlab进行实例计算,并与其他预测方法比较。结果表明,该模型有较高的预测精度,优于单个模型,预测效果更优于其他方法。     

硅烷涂层对腐蚀性水环境下水泥基材料的保护试验

暴露在腐蚀性水环境下的混凝土结构的破坏是各种工业、桥梁设施面临的主要问题。在混凝土结构表面涂刷保护涂料是一种避免混凝土遭受破坏的简单可行的办法。本文介绍了涂覆乙烯基苯丙烯酸硅烷涂料的圆柱体和立方体砂浆试块在3%硫酸溶液、7000mg/l的无水硫酸钠溶液和模拟海水环境中侵蚀试验,结果显示经过这种硅烷涂料处理的砂浆试块具有优异的耐海水和抵抗硫酸盐的能力,但是在3%硫酸溶液中,试块的表面被严重破坏,重量变化明显。     

局部热暴露对人体全身热反应的影响

介绍了有关局部热暴露的研究背景和重要进展，包括局部热暴露环境参数对局部热感觉的影响，局部热感觉对全身热反应的影响，不同部位的局部热感觉对全身热感觉影响的权重，以及相关的心理学和生理学研究现状。讨论了局部热暴露环境评价指标的选取和局部热暴露作用部位的选择，并指出了今后的研究方向。     

对房屋成新度确定方法的探讨

对房屋质量等级的判定建立了模糊数学综合评判模型，提出了对旧房价格评估的成新度计算方法。     

地下工程围岩稳定性的模糊综合评判法

围岩稳定性受多种不确定性因素的影响，不仅具有随机性，也具有模糊性。选择影响围岩稳定性的一些主要因素，采用模糊数学综合评判方法，对围岩稳定用模糊语言进行不同程度的评价，得出了合理的结果。     

Pore blockage effect of NOM on atrazine adsorption kinetics of PAC: the roles of PAC pore size distribution and NOM molecular weight

Natural organic matter (NOM) in natural water has been found to have negative effects on the adsorption of various trace organic compounds by activated carbon through two major mechanisms: direct competition for sites and pore blockage. In this study, the pore blockage effect of NOM on atrazine adsorption kinetics was investigated. Two types of powdered activated carbon (PAC) and three natural waters were tested to determine the roles of PAC pore size distribution and NOM molecular weight distribution in the pore blockage mechanism. When PAC was preloaded with natural water, the pore blockage effect of the NOM was found to cause a reduction of up to more than two orders of magnitude in the surface diffusion rate of atrazine compared to simultaneous adsorption of atrazine and NOM with fresh PAC. The surface diffusion coefficient of atrazine for preloaded PAC decreased with a decrease in PAC dose or an increase in NOM surface concentration. Because of the pore blockage effect of NOM, a 30% drop in atrazine removal was observed in a continuous flow PAC/microfiltration (MF) system after 7 days of contact compared to the removal predicted from the batch isotherm test. Large micropores and mesopores were found to play an important role in alleviating the effect of pore blockage. A PAC with a relatively large fraction of large micropore and mesopores was shown to suffer much less from the pore blockage effect compared with a PAC that had a much smaller fraction of large pores. Natural waters with different NOM molecular weight distribution caused different extent of pore blockage. The NOM molecules with molecular weight between 200 and 700 Dalton appeared to be responsible for the pore blockage effect.     

气象分层对地炮弹道虚温偏差量计算的影响

为了研究不同弹道气象分层方法对地炮弹道虚温偏差量(BVTD)计算结果的影响,论述了炮兵弹道气象分层方法,分析了目前研究中弹道分层方法存在的问题,基于实际探空资料计算了不同分层数量下的BVTD。结果表明:随着弹道气象分层数量的增加,最终BVTD将逐渐趋近于一理想值,当弹道气象分层数量达到20层时,BVTD即可达到与高空气象探测一致的误差水平;增加弹道气层分层数量,将提高地炮BVTD的计算精度,有助于提高炮兵气象保障的水平。     

基于正态云关联度的军事后勤仓库选址评估

针对军事后勤物资仓库的战略性、经济性等特点,构建仓库选址评估指标体系;为减少因评估过程随机性、指标标准确定模糊性等主、客观因素对选址评估造成的不利影响,引入正态云的概念;给定理想状态下指标体系的标准正态云,构建各选址方案正态云评估矩阵,采用计算评估云与标准云关联度的方法评估各选址方案;用熵权法计算各项指标权重,将各方案评估云与标准云关联度的加权和作为选址方案的综合评估指数,根据综合评估指数大小衡量各方案优劣,通过应用示例说明该方法对军事后勤仓库选址评估具有一定的参考价值。