Extending Anisotropic Perfectly Matched Layer Absorbing Boundary Condition to Biaxial Media

The absorbing boundary condition required for an anisotropic perfectly matched layer for materials that exhibit a uniaxial and biaxial permittivity tensor is investigated. These materials are used in optical and millimeter wave devices and other particular situations such as in the construction of modern aircraft and automobiles. The derivation presented in this paper may be not suitable for all the arbitrary orientations but for many common situations. The effectiveness of the condition is also illustrated with examples by the finite-difference and finite-element method.     

电磁驱动的金属泵结构设计和工作原理分析

设计电磁驱动的金属泵机械结构,分析其振动机理,确定其输出功率的影响因素,比较金属泵和压电泵的优缺点。     

基于高阶叠层基函数的加速迭代求解方法

研究了高阶叠层矢量基函数的尺度因子对迭代法求解矩阵方程收敛性的影响,选择了可以有效降低矩阵条件数的尺度因子;在此基础上,详细阐述了求解基于高阶叠层矢量基函数阻抗矩阵方程的叠层共轭梯度方法(HCGM),并从理论上分析了叠层共轭梯度算法的收敛性能.通过计算实例表明,与共轭梯度方法(CGM)相比.使用HCGM可以大幅度减少矩阵方程的迭代求解时间.     

一种利用反射电极偏压的半反半透LCD

介绍了一种VA模式反射电极偏压的常黑单盒厚半反半透LCD。在透射区,形成连续且均匀的贯穿液晶层的电场;而在反射区,电场则主要由电极表面形状控制。由此,可使透射区的位相延迟约是反射区的2倍。这样一种半反半透LCD不论透射区还是反射区都有很高的光透过率(>90%),同时二者灰阶特性重合度也很好。     

2,5—二氯苯胺防蛀剂的高效液相色谱分析

介绍了用高效液相色谱法快速测定新型防蛀剂２,５－二氯苯胺的方法,分离柱为ＨｙｐｅｒｓｉｌＣ１８柱,淋洗液为乙腈－水－醋酸（７０：２８：２）。该方法操作简便,分离条件较好,回收率大于９９％,变异系数为０．３５％。     

遥控空拍技术关键问题及其应用

针对遥控空拍技术的技术特点和应用实际，从飞行器的合理选择、系统的市场定位、系统指标的设计、系统的开放性等几个关键问题入手，简要阐述了遥控空拍技术在设计研制过程中面临的主要问题，并列举了遥控空拍技术的几个典型应用实例。     

光通信用塑料光纤及其系统应用

详细分析了塑料光纤的结构、特性以及其相关通信系统网络组件;分析了应用质子注入技术可以解决塑料光纤通信系统光探测器光敏面积和响应带宽之间的矛盾;最后通过最新的塑料光纤通信系统应用总结了塑料光纤的现状,讨论了POF通信系统其面临的问题。     

基于日志模板的异常检测技术

日志分析是云计算业务平台管理中一项非常重要的工作.日志分析旨在保证云平台的高效性与可用性,传统的人工分析方式存在日志复杂、日志量大等问题.本文提出了一种日志异常检测方法,首先基于编辑距离进行文本聚类形成日志模板,在此基础上构建特征向量,利用弱分类器训练形成得分特征向量,利用得分特征向量与随机森林构建强分类器.实验表明,日志模板与真实模板之间的互信息为0.91,较为接近,利用随机森林构建的强分类器在本文的数据集上表现最好,分类精度达0.94.     

会话边缘控制器关键技术实现

通过对会话边缘控制器(SBC)及相关的SIP协议、网络地址转换/防火墙、媒体处理、拓扑隐藏及协议修改技术的说明,给出了SBC的核心模块的设计原型,并对信令代理和媒体代理关键子模块进行了设计实现说明。采用B2 BUA、状态机、SIP/RTP/RTCP消息修改、地址映射、回调函数、媒体流处理、服务质量(QoS)控制策略等技术,对系统做了具体实现。测试结果表明,系统具备了作为一个SBC的功能。     

Studies of high DC current induced degradation in III-V nitridebased heterojunctions

We report experiments on high dc current stressing in commercial III-V nitride based heterojunction light-emitting diodes. Stressing currents ranging from 100 mA to 200 mA were used. Degradations in the device properties were investigated through detailed studies of the current-voltage (I-V) characteristics, electroluminescence, deep-level transient Fourier spectroscopy and flicker noise. Our experimental data demonstrated significant distortions in the I-V characteristics subsequent to electrical stressing. The room temperature electroluminescence of the devices exhibited a 25% decrement in the peak emission intensity. Concentration of the deep-levels was examined by deep-level transient Fourier spectroscopy, which indicated an increase in the density of deep-traps from 2.7×10¹³ cm^-3 to 4.2×10¹³ cm^-3 at E₁=E _C-1.1 eV. The result is consistent with our study of 1/f noise, which exhibited up to three orders of magnitude increase in the voltage noise power spectra. These traps are typically located at energy levels beyond the range that can be characterized by conventional techniques including DLTS. The two experiments, therefore, provide a more complete picture of trap generation due to high dc current stressing