自毁装置的安全性和可靠性

为了研究集束弹药自毁装置的安全性与可靠性,分析和评价自毁装置设计,对自毁装置进行了理论抽象,建立了自毁装置安全性失效模型; 引入信息论方法,建立了抽象自毁装置顺序控制起爆信息输出量和顺序时间窗控制起爆信息输出量模型; 对典型的M85子弹药引信、XM1161引信、M230SD引信安全性及可靠性进行了分析。理论分析表明,M230SD引信安全性及可靠性优于XM1161引信、M85子弹药引信,与实验结果一致。     

局部对立条件下斜率变点估计的收敛速度

对至多只有一个斜率变点的模型,在误差分布为非正态时,本文利用滑窗方法研究了局部对立假设下变点估计的相合性和收敛速度问题,同时给出了部分模拟结果.     

晶体硅太阳电池双层电极优化分析与实验研究

相对于单层电极结构,优化的前表面双层电极能够明显减小功率损失,改善晶体硅太阳电池的电学特性．本文对晶体硅太阳电池的双层电极进行了优化分析和实验研究.通过扫描电子显微镜观测将双层电极的截面抽象为更接近于实际的半椭圆型,建立了太阳电池前表面的双层电极模型,理论分析了双层电极的电学损失和光学损失.结合丝网印刷后光诱导电镀太阳电池的实验,得到了理论和实验上的最优化光诱导电镀增厚电极厚度与丝网印刷电极宽度的关系.所得到的理论和实验结果符合良好.由于并不涉及电极制备的具体技术,双层电极理论模型普遍适用于多种类型的双层电极结构.     

弹性需求下城市公交网络服务的优化

对具有弹性需求的城市公交网络系统进行了票价结构与发车频率组合的优化。考虑到公交定价和发车频率会影响乘客需求以及乘客对路径的选择行为,将这一问题描述为一个双层规划问题,上层是寻求社会福利最大的优化问题;下层考虑了乘客的出行选择行为,为弹性需求下乘客在城市公交网络上流量分布的随机用户平衡分配模型。鉴于双层规划问题的非凸性,运用模拟退火算法对模型进行求解,并给出一个仿真算例说明提出的模型和算法的合理性。     

用云纹干涉法测量和研究双层钴合金的挠度

运用云纹干涉原理对双层钴-合金材料进行三点弯曲试验,测试其常温与高温条件下的挠度值.通过大量试验,且与千分表测试的挠度值进行比较.结果表明,常温条件下的云纹测试挠度值与千分表法可以达到同样的精确度.同时,该实验方法体现了高温云纹干涉法在材料高温力学性能测试方面的优越性.高温云纹法是非接触式测量,在高温环境下有效地解决了量具高温变形的困难,且结合云纹图像可以对试件受力动态变形情况进行实时观测和分析,是一种较为精确测试常温及高温挠度的新方法.     

双层网格圆底扁球壳的非线性稳定问题

从基于等效夹层壳思想的双层网格扁壳,非线性弯曲理论的变分方程出发,利用坐标变换方法和驻值余能原理,导出双层网格圆底扁球壳,在均布压力作用下的轴对称大挠度方程和边界条件．采用修正迭代法,求得了两类边界条件下双层网格圆底扁球壳的非线性载荷-位移关系式和临界屈曲载荷的解析表达式,并讨论了几何参数对临界屈曲载荷的影响．     

8-羟基喹啉镧两亲性配合物LB膜的双层电致发光器件

以具有不同层数的两亲配合物二[2-(N-十六烷基氨基甲酰基)-8-羟基喹啉]合镧[La(HQ)₂Cl]的LB膜为发光层,PBD为电子传输层,制备了双层结构的电致发光(EL)器件:ITO/LB膜/PBD/Al.器件产生黄绿色注入式发光.LB膜的层数和沉积压对器件的性能具有重要影响.在16V激发电压下,5,11和21层LB膜双层EL器件的电流密度分别为48,29和16.4mA/cm²,启亮电压阀值为7.5,8.5和9.5V.器件的亮度随电流密度和驱动电压的增加而增加.在相同偏压下,21层LB膜EL器件的亮度大于5和11层LB膜的器件.在25mN/m沉积的LB膜制备的EL器件具有较高的亮度(1219cd/m₂)和击穿电压.     

低反射低吸收高平均功率输出窗的设计

 对高平均功率微波、毫米波输出窗的反射和吸收功率进行了理论分析，以蓝宝石输出窗为例，给出了低反射、低吸收的高平均功率回旋速调管放大器输出窗的设计方案。该放大器输出窗厚度为1.35mm，半径为9mm，工作频率为34GHz，在加工误差小于2%的情况下，输出窗反射率小于1%，当平均输出功率为10kW时窗片的吸收功率为2.5W。     

Three-body entanglement induced by spontaneous emission in a three two-level atoms system

We study three-body entanglement induced by spontaneous emission in a three two-level atoms system by using the entanglement tensor approach. The results show that the amount of entanglement is strongly dependent on the initial state of the system and the species of atoms. The three-body entanglement is the result of the coherent superposition of the two-body entanglements. The larger the two-body entanglement is, the stronger the three-body entanglement is. On the other hand, if there exists a great difference in three two-body entanglement measures, the three-body entanglement is very weak. We also find that the maximum of the two-body entanglement obtained with nonidentical atoms is greater than that obtained with identical atoms via adjusting the difference in atomic frequency.     

A set of Boussinesq-type equations for interfacial internal waves in two-layer stratified fluid

Many new forms of Boussinesq-type equations have been developed to extend the range of applicability of the classical Boussinesq equations to deeper water in the study of the surface waves. One approach was used by Nwogu (1993. J. Wtrw. Port Coastal and Oc. Eng. 119, 618--638) to improve the linear dispersion characteristics of the classical Boussinesq equations by using the velocity at an arbitrary level as the velocity variable in derived equations and obtain a new form of Boussinesq-type equations, in which the dispersion property can be optimized by choosing the velocity variable at an adequate level. In this paper, a set of Boussinesq-type equations describing the motions of the interfacial waves propagating alone the interface between two homogeneous incompressible and inviscid fluids of different densities with a free surface and a variable water depth were derived using a method similar to that used by Nwogu (1993. J. Wtrw. Port Coastal and Oc. Eng. 119, 618--638) for surface waves. The equations were expressed in terms of the displacements of free surface and density-interface, and the velocity vectors at arbitrary vertical locations in the upper layer and the lower layer (or depth-averaged velocity vector across each layer) of a two-layer fluid. As expected, the equations derived in the present work include as special cases those obtained by Nwogu (1993, J. Wtrw. Port Coastal and Oc. Eng. 119, 618-638) and Peregrine (1967, J. Fluid Mech. 27, 815-827) for surface waves when the density of the upper fluid is taken as zero.