基于空中交通网络节点最大流的性能分析

以减少空中交通延时为目的,从理论角度研究了空中交通网络的最大流.利用离散时间消失排队系统,计算得到了机场节点最大流的理论上界,并且对该理论上界进行了性能分析.通过仿真实验,验证了方法的有效性.     

局部战争对炮兵信息化建设的启示

本文通过对近几次局部战争特别是伊拉克战争的研究,分析信息化战争的特点、规律,从而得出炮兵在信息化战争中的作用和地位,以及炮兵应对信息化战争的建设思路。     

长行程屈曲约束支撑拟静力试验

为研究长行程屈曲约束支撑(buckling restrained brace,BRB)的抗震性能,针对不同有效屈服长度比的屈曲约束支撑进行了拟静力试验研究,对比分析了试件的滞回曲线、骨架曲线、延性系数、耗能能力、刚度退化和强度退化等性能指标.结果表明:高有效屈服长度比能够有效提高试件的极限承载力和极限位移;长行程屈曲约束支撑的延性系数为2.54～3.60,延性较好;有效屈服长度比对长行程屈曲约束支撑的刚度退化性能影响不大;高有效屈服长度比的长行程屈曲约束支撑,强度退化更稳定;抗震性能有所提高.     

壁判据检验激波/层流边界层干扰流动的数值计算

针对二维激波/层流边界层干扰流动数值计算结果的可信度问题,根据高智研究员提出的壁判据对数值计算结果进行了分析和可信度评估.对于二维可压流动,在壁面附近,已经证明壁判据与NS方程解析解相吻合,数值计算结果也表明达到了网格无关性,而利用Opencfd算出的数值解却发现:随着网格的逐渐加密,切向动量壁判据和能量壁判据吻和得越来越好,而法向动量壁判据仍然有较小的差距,但并不影响流场的结果,其原因是壁面压力边界条件选取不当.数值计算结果表明,壁判据可以作为含壁面流动的一种CFD计算结果可信度评估的工具,具体的评估标准仍需进一步研究.     

水泥改良土融沉对地层位移场影响的数值分析

【目的】分析水泥改良土融沉对地层位移场的影响规律,为水泥土改良冻结法应用于城市地下工程提供理论基础。【方法】以南京地铁10号线盾构出洞水平冻结加固工程为研究对象,采用三维数值模拟方法对水泥改良土融沉引起的地层位移进行了分析,采用单因素分析法,分析了融沉系数、覆土厚度、冻土壁尺寸对融沉位移场的影响规律。【结果】冻结区土体未经水泥土改良时,地表最大融沉量为12.811 cm; 水泥掺入比为12%时,地表最大融沉量为1.521 cm,表明水泥的掺入可明显减小冻土融沉。【结论】水泥土融沉时,土层越深,融沉位移越大,融沉范围越小; 地表融沉位移呈盆状沉降面,最大沉降位于出洞口处,随融沉系数增加,地表最大融沉量逐渐增大,但地层沉降分布规律不变; 覆土厚度越大,地表融沉量越小; 冻土壁尺寸增加时,地表位移发展速度变缓,地表沉降时间延长,最终融沉量增大。     

葡萄牙的“黄金时代”

葡萄牙经济近年来发展迅速,主要得益于稳定的政局和符合国情的经济政策及措施;社民党提出的“有控制的扩展战略”似将继续发挥作用。     

Sm-Co非晶垂直磁化膜厚度的椭圆偏振法测量

本文叙述了用椭圆偏振法测定Sm-Co非晶垂直磁化膜厚度的列线图法和搜索法,并对该膜样品进行了测量,结果表明这两种方法是简便可行的。     

Pilot Test of Advanced Treatments Combination of Wastewaterfor Groundwater Recharge

IntroductionInterests in artificial groundwater recharge ofreclaimed wastewater have been strengthened inrecent years in response to declining groundwaterlevels,increased vulnerability of surface watersupplies to contamination,opposition to increasedreliance upon surface water supplies and manyother reasons[14 ] .　A demonstration plantwill be builtin Beijing forartificial groundwater recharge with reclaimedwastewater effluent as a showplace and trainingcenter in China.This project was undert…     

Treatment of Organic Compounds in Reclaimed Wastewater for Groundwater Recharge

To study water quality problems associated with groundwater recharge, a tertiary treatment process, consisting of coagulation, sand filtration, and granular activated carbon (GAC) adsorption, was used in combination with a simulated soil aquifer treatment. The process significantly improved secondary effluent quality. GAC adsorption reduced organic substances expressed by UV-254, dissolved organic carbon as well as partially adsorbable organic halogens. The results of the Ames test show that the secondary effluent contains a high concentration of mutagens. GAC filtration removed adsorbable organic bromine slightly whereas GAC adsorption removed mutagens effectively. The simulated soil aquifer treatment was able to further reduce UV-254, dissolved organic carbon, and adsorbable organic halogens through biodegradation. Adsorbable organic bromine levels were also reduced by the soil aquifer treatment process. The given reclamation technology used for groundwater recharge is of benefit to the removal of dissolved organic carbon, UV-254, adsorbable organic halogens, and rnutagenicity.     

Poisson分布中未知参数的精确置信区间

 用假设检验法构造了Poisson分布中未知参数的置信下限和上限,及精确置信区间,为实际应用提供了理论依据.