纳微米聚合物颗粒分散体系微孔滤膜流动特征

为了评价纳微米聚合物颗粒分散体系在低渗透油藏中的流动特征,利用微孔滤膜模拟低渗透油藏的喉道,采 用激光粒度仪和微孔滤膜过滤装置,对其流动特征及其影响因素进行了研究。结果表明：水化时间小于120 h 时,聚 合物颗粒的封堵作用较强;水化时间大于120 h 后,聚合物颗粒逐级调驱能力增强;随着压力差增大,聚合物颗粒储层 深处逐级调驱的效果增强,压力差大于0.15 MPa 后,逐级调驱效果增加的速度明显加快;随着滤膜孔径减小,聚合物 颗粒过滤速度急剧降低,在0.45,0.80µm 微孔滤膜上粒径为1.68µm 聚合物颗粒具有很强的封堵能力,而在3.0 µm 微 孔滤膜上具有较强的储层深部逐级调驱效果;随着聚合物颗粒浓度增加,储层深部逐级调驱效果变弱,颗粒浓度增至 2.0 g/L 后,聚合物颗粒已经没有深部逐级调驱的效果。     

一种高速卷积的实时实现方法

卷积是数字信号处理的基本算法，本文介绍了一种实时实现高速卷积的体系结构，采用甚超大规模集成电路芯片ＬＨ９１２４和ＦＰＧＡ器件实现了７０ＭＨ＿Ｚ带宽信号卷积的实时处理。该系统已应用于机载合成孔径雷达实时信号处理机的脉压系统。     

Comparative Risk Analysis of Dioxins in Fish and Fine Particles from Heavy-Duty Vehicles

Dioxins and airborne fine particles are both environmental health problems that have been the subject of active public debate. Knowledge on fine particles has increased substantially during the last 10 years, and even the current, lowered levels in the Europe and in the United States appear to be a major public health problem. On the other hand, dioxins are ubiquitous persistent contaminants, some being carcinogens at high doses, and therefore of great concern. Our aim was to (a) quantitatively analyze the two pollutant health risks and (b) study the changes in risk in view of the current and forthcoming EU legislations on pollutants. We performed a comparative risk assessment for both pollutants in the Helsinki metropolitan area (Finland) and estimated the health effects with several scenarios. For primary fine particles: a comparison between the present emission situation for heavy-duty vehicles and the new fine particle emission standards set by the EU. For dioxins: an EU directive that regulates commercial fishing of Baltic salmon and herring that exceed the dioxin concentration limit set for fish meat, and a derogation (= exemption) from the directive for these two species. Both of these two decisions are very topical issues and this study estimates the expected changes in health effects due to these regulations. It was found that the estimated fine particle risk clearly outweighed the estimated dioxin risk. A substantial improvement to public health could be achieved by initiating reductions in emission standards; about 30 avoided premature deaths annually in the study area. In addition, the benefits of fish consumption due to omega-3 exposure were notably higher than the potential dioxin cancer risk. Both regulations were instigated as ways of promoting public health.     

基于改进粒子群优化方法的供应商优选与订货量分配模型

研究了随机性需求环境下的供应商优选与订货量分配问题,构建了以质量、成本、交货期3个准则为目标函数、以其他目标为约束条件的多目标随机约束规划模型;借助于加权法和罚函数法,将多目标随机约束规划模型转化为单目标优化模型;进而设计了带惯性因子和收缩因子的粒子群优化求解算法对所建模型进行求解,并与常用的遗传算法求解方法进行对比分析,实例验证了粒子群优化算法解决此类优化问题的可行性和有效性.     

基于磁阻传感器的磁靶向药物实时示踪系统设计

目的:设计基于磁阻传感器的检测系统,实现实时磁靶向药物运动轨迹的跟踪?方法:用Fe-Fe3O4核壳结构纳米颗粒模拟磁靶向药物,磁阻传感器检测到其磁场信号进行处理和变换,得到其空间位置信息?结果:用LabVIEW软件实现实时检测,实时显示磁性颗粒运动位置?结论:检测系统具有良好的实时性及精准度,可为临床研究磁靶向药物的在体检测提供一种新方式?