考虑法向压力梯度的三维旋转边界层计算

本文以量级分析为基础,建立了一般曲线坐标系上的三维旋转边界层方程。对旋转在边界层中的影响进行分析之后,提出了一个能够处理壁面法向压力梯度不为零问题的压力梯度迭代方法。在传统的Box法的基础上发展了一套完整的求解三维旋转边界层的方法和程序,并对螺旋面、压气机转子叶面以及圆柱面上的旋转边界层进行了计算,与他人的计算和实验的对比分析表明,该方法和程序是正确的,可用于求解任意几何物面上的三维旋转边界层。     

空腹式刚架拱桥梁拱节点三维光弹性试验研究

福州市尤溪洲闽江大桥是国内首座在拱肋（圈）上不设立柱和斜撑的空腹式刚架拱桥．作为空腹式刚架拱桥受力关键部位——梁与拱的连接部位，受力及构造复杂．通过三维光弹性试验，研究该梁、拱结合部的内力传递、应力集中、局部应力分布规律，为空腹式刚架拱桥节点设计、施工提供依据．     

Extraction and concentration of vapors from fire debris for forensic purposes: Evaluation of the use of Radiello Passive Air Sampler

The Radiello Passive Air Sampler is one of the latest innovations developed for the sampling of pollutants in the air by passive headspace. It has been reported that its properties allow an enhanced sensitivity, reproducibility and adsorption capacity. It therefore appears to be of interest in the extraction of potential residues of ignitable liquids present in fire debris when arson is suspected.A theoretical approach and several laboratory tests have made it possible to precisely characterize in a forensic perspective the potential of the device in extracting and concentrating the vapors of ignitable liquids found in fire debris. Despite some advantages, the Radiello device appears to be less efficient than traditional axial symmetry samplers.     

Analysis of amphetamine and methamphetamine as emerging pollutants in wastewater and wastewater-impacted streams

The identification and quantitation of the non-ecstasy amphetamine-type stimulants (ATSs) amphetamine and methamphetamine in lakes, rivers, wastewater treatment plant influents, effluents, and biosolids are reviewed. Neither monitoring nor reporting is required of these ATSs, which are considered emerging pollutants, but they have been identified in the environment. Amphetamine and methamphetamine enter our water supply by human excretion after legal or illegal consumption and via manufacturing in clandestine laboratories. Analytical methodology for sampling, sample preparation, separation, and detection of ATSs is discussed. Reported occurrences of ATSs in the environment and their use in municipal sewage epidemiology are noted. Future research needs that challenge applications of analytical techniques are discussed. The review focuses on research reported from 2004 to 2009.     

标准镜的高精度柔性支撑镜框的优化设计

为了实现干涉仪标准镜中光学元件的高精度定位,设计了一种柔性支撑镜框,研究了该结构的力学模型、结构参数、定位精度和透镜变形。首先,根据材料力学原理将柔性镜框等效为一个弹簧系统;根据力学方程和几何关系,建立了透镜中心位置与柔性结构的挠度之间的二元方程。然后,分析了安装位置、温度、结构参数对透镜位置以及作用力的影响。最后,应用有限元仿真分析了所设计结构的力学性能,并进行对比验证。结果表明,数值仿真分析的结果与有限元仿真结果基本相同,柔性镜框的柔性结构厚度最优值为1.5 mm。该设计方案完全满足干涉仪标准镜对镜框在定位精度、稳定性方面的要求。     

基于经典光学方法的物体表面微观结构的三维成像

设计了基于经典光学方法的物体表面微观结构的三维成像实验装置以及相应计算程序,从记录不同角度平行光照射下的物体表面照度出发,经图片处理后得到物体表面的三维立体结构.     

激光辐照下复合材料树脂基热分解3维温度场模型

 采用控制体积法,从质量和能量守恒角度,推导了激光辐照下复合材料树脂基热分解时温度变化的基本方程。用多步模型描述树脂的热分解反应。提出了热分解气体的1维运动假设,这使得可以在3维情况下考虑热分解气体对流传输的影响,且在不引入力学量的前提下实现3维温度场模型的封闭。考虑到树脂基复合材料的各向异性,对部分分解材料的导热率计算公式进行了推导,并重新推导了部分分解材料对激光的吸收系数计算公式。在一定的简化下,推导的能量守恒方程与文献结果一致。     

高功率激光装置打靶精度测试技术

 多路激光打靶精度在惯性约束聚变实验中起着至关重要的作用,提出了基于X光针孔相机的激光打靶精度测试方法。根据显微镜读取的靶平面坐标系的靶孔中心坐标及打多孔靶后X光针孔相机所记录的靶孔中心坐标,建立靶平面坐标系和X光针孔相机坐标系之间的转换关系;通过打焦斑靶,建立焦斑模板,采用套模板的方法,读取X光针孔相机坐标系中焦斑中心坐标;由靶平面坐标系和X光针孔相机坐标系之间的转换关系,求出靶平面坐标系中焦斑中心坐标,计算得到激光打靶精度,分析打靶精度测试结果的不确定度,从而给出多路激光打靶精度测量技术和方法。     

A study on volunteer augmentation navigation technology

Navigation augmentation technology is one of the most common methods to increase the continuity,reliability and integrity of the global satellite navigation system.The concept of volunteer augmentation navigation (VNA) is proposed and the elements and topological structure of VNA are also analyzed in this paper.The study focuses on the neural network model that volunteers and ordinary users use modern communication information network to exchange self-organizing information.The neural cell model of Voluntee...