Al型Wey1群子根系轨道生成的格

利用Weyl群的性质及置换理论,讨论了Al型Weyl群作用下的子根系轨道生成的格.在同类型格中,研究了不同格之间的包含关系,给出了一个子根系是给定由μ生成的格L(μ)中一个元素的条件,最后讨论了按包含关系或反包含关系规定L(μ)的偏序时,L(μ)是否为几何格.     

乙烯裂解炉辐射段炉管Cr20Ni32Nb材料的焊接工艺

乙烯裂解炉炉管采用的高铬镍合金材料在焊接过程中易出现热裂纹的问题,针对该问题,在工程实际中对乙烯裂解炉辐射段炉管材料—Cr20Ni32Nb进行焊接性分析和焊接工艺评定,采用“超合金化”焊接材料,并制定合理的焊接工艺,成功地解决了Cr20Ni32Nb高铬镍材料离心铸造炉管的焊接热裂纹问题。     

Simulation of interconnect inductive impact in the presence of process variations in 90 nm and beyond

The on-chip inductive impact on signal integrity has been a problem for designs in deep-submicrometer technologies. The inductive impact increases the clock skew, max timing, and noise of bus signals. In this letter, circuit simulations using silicon-validated macromodels show that there is a significant inductive impact on the signal max timing (/spl sim/ 10% pushout versus RC delay) and noise (/spl sim/2/spl times/RC noise). In nanometer technologies, process variations have become a concern. Results show that device and interconnect process variations add /spl sim/ 3% to the RLC max-timing impact. However, their impact on the RLC signal noise is not appreciable. Finally, inductive impact in 65- and 45-nm technologies is investigated, which indicates that the inductance impact will not diminish as technology scales.     

Characteristics of a 12-domain MVA-LCD

A multi-domain (12-domain) vertical alignment liquid crystal display (MVA-LCD) device is proposed and its electro-optic characteristics evaluated through a 3-D simulator. The MVA-LCD exhibits advantages in wide viewing angle, high transmittance, fast response time, and small color shift when a pair of wide view crossed circular polarizers is employed. Potential applications of this MVA-LCD for high quality LCD TVs and computer monitors are emphasized.     

Quality-of-service provisioning and efficient resource utilization in CDMA cellular communications

One of the major challenges in supporting multimedia services over Internet protocol (IP)-based code-division multiple-access (CDMA) wireless networks is the quality-of-service (QoS) provisioning with efficient resource utilization. Compared with the circuit-switched voice service in the second-generation CDMA systems (i.e., IS-95), heterogeneous multimedia applications in future IP-based CDMA networks require more complex QoS provisioning and more sophisticated management of the scarce radio resources. This paper provides an overview of the CDMA-related QoS provisioning techniques in the avenues of packet scheduling, power allocation, and network coordination, summarizes state-of-the-art research results, and identifies further research issues.     

激光雷达距离像相关跟踪中的图像预处理

相干激光雷达距离像预处理是获得最终图像必不可少的步骤,其处理的好坏直接关系到目标识别的正确与否及追踪的稳定性.本文首先通过基于相干激光雷达特性得到仿真激光雷达含噪距离像与强度像,进而对原始噪声图像进行了背景抑制与距离反常抑制(中值滤波)以及二者结合预处理.用基于MCD距离的相关算法对处理前、后图像进行追踪.最后给出跟踪绝对误差.     

基于水平集的图像分割方法在箱包DR-CT检测系统中的应用

将水平集活动轮廓跟踪算法引入箱包DR-CT检测系统的图像处理中，针对箱包DR图像特点，利用水平集算法不需预知待检图像拓扑模型，且在复杂拓扑情况下对图像分割效果较好的优点，对图像进行分割。实验表明，该方法能有效的实现箱包DR图像分割。     

生物芯片技术的应用与展望

生物芯片技术是20世纪90年代中期发展起来的一项尖端技术,已经成为科学界的研究热点之一。简述了生物芯片的概念与主要分类,主要介绍了生物芯片技术在基因测序与基因表达分析、基因突变和多态性检测、转基因食品的检测、食品中微生物的检测、临床医学、疫苗研制等方面的最新应用,并对其在中药研究以及农业、环保、司法鉴定、基因武器等领域的发展前景作了预测及展望。     

改性三聚氰胺氰尿酸盐阻燃玻纤增强PA6的研究

采用改性三聚氰胺氰尿酸盐阻燃玻纤增强尼龙6,考察了阻燃材料的阻燃性能、加工流变性能、力学性能及热变形温度,分析了该阻燃剂的作用机理。     

四价钒离子VO2+在几种阳离子交换膜中的自扩散行为

研究了VO2 在3种阳离子交换膜PE01,NF120以及Nafion1135中的自扩散行为,采用UV-3802可见-紫外分光光度仪测定VO2 浓度,建立浓度与时间的关系,用Ct=Ct∞(1-exp(-αt))经验方程拟合实验数据,得到VO2 在3种膜PE01,NF120以及Nafion1135中的自扩散方程.结合Fick扩散理论,推导出了VO2 在膜中的扩散系数D与方程中经验常数α的关系,计算出了VO2 在3种阳离子交换器Nafion1135,PE01以及NF120中的扩散系数分别为2.66×10-13,2.09×10-13和3.26×10-13m2/s.在所研究的阳离子交换膜中,PE01膜对VO2 具有最好的阻隔作用.