Study of Corrugated Elliptical Waveguides for Slow-Wave Structures

The slow-wave characteristics taking account of space harmonics for confocal corrugated elliptical waveguides are presented. By using the field-matching method, the dispersion equation, and the mean interaction impedance for odd hybrid modes of this structure are derived. Based on our results, changing the waveguide eccentricity can improve the dispersion characteristics and the interaction impedance for _oEH₀₁ mode     

商用车CAN总线仪表开发与设计

本文阐述了汽车仪表的功能、作用及现状,介绍了商用车CAN总仪表的性能特点及总体构成,对系统各部分功能模块的软、硬件结构及功能设计原理进行了细致说明.对于在车辆中存在的各种随机干扰,本文强调了几种抗干扰滤波方法与措施.     

IC封装载板的新型表面涂饰层——ENEPIG

文章介绍一种新型的化学镀镍化学镀钯与浸金表面涂饰层,克服了化学镀镍浸金涂层的缺点,更加适合于IC封装载板上应用。     

全位置药芯焊丝自保护焊厚壁钢管焊接试验

为了解决长输管道安装工程中全位置自动化焊接问题,采用自行研制的全位置焊接机器人BIPT3,采用自保护药芯焊丝对管径为4 m壁厚为60 mm的输水钢管进行了打底、填充和盖面焊接.实现了大管径钢管的药芯焊丝自保护焊的全位置自动化焊接.焊接过程稳定,无咬边和驼峰现象,焊接工艺优良,电弧稳定,焊缝外形美观.     

集成在ERP采购管理中的数据挖掘技术

设计实现一个可扩展的、开放的集成在ERP采购管理系统中的数据挖掘系统.采用DM与DB/DW紧耦合方式构建,使用基于约束的交互式数据挖掘技术,将计算模型和工具分离,通过人机界面和知识推理接受用户决策需求并输出决策结果.     

基于UDP的局域网内时钟同步协议

当前在网络应用中,广泛采用NTP和SNTP进行时钟同步,但NTP协议非常复杂且精度受限于外部条件.在分析某类网络应用特性的基础上,提出一个新的适合于此类应用的时钟同步协议.该协议实现简单而且可以达到很高的时钟精度.     

DCG-VCS:一种基于DCG的版本管理系统

传统的版本管理系统只提供基于文件系统的版本管理,难以支持需要图状结构的应用的版本管理.提出一种基于有向带圈图(DCG)的版本管理系统DCG-VCS,它能够处理任意有向带圈图结构的版本化问题.在分析传统版本管理系统所存在问题的基础上,提出了有向带圈图结构DCG的版本化模型,详细阐述了DCG-VCS的主要设计问题,包括中央库的储存模型和版本编号、签入和签出算法,一致性维护和签入并发性保证等.最后讨论了DCG-VCS在语义网络的知识管理中的应用.     

BAAQ: an infrastructure for application integration and knowledge discovery in bioinformatics.

The emerging grid computing technologies enable bioinformatics scientists to conduct their researches in a virtual laboratory, in which they share public databases, computational tools as well as their analysis workflows. However, the development of grid applications is still a nightmare for general bioinformatics scientists, due to the lack of grid programming environments, standards and high-level services. Here, we present a system, which we named Bioinformatics: Ask Any Questions (BAAQ), to automate this development procedure as much as possible. BAAQ allows scientists to store and manage remote biological data and programs, to build analysis workflows that integrate these resources seamlessly, and to discover knowledge from available resources. This paper addresses two issues in building grid applications in bioinformatics: how to smoothly compose an analysis workflow using heterogeneous resources and how to efficiently discover and re-use available resources in the grid community. Correspondingly an intelligent grid programming environment and an active solution recommendation service are proposed. Finally, we present a case study applying BAAQ to a bioinformatics problem.     

A CODING SCHEME USING GLOBAL MOTION ESTIMATION FOR AVS P-FRAME

Block matching has been used for motion estimation and motion compensation in the Audio and Video Standard （AVS） for years. While having an acceptable performance in describing motion between frames, it requires quite a few bits to represent the motion vectors. In certain circumstances, the use of global motion estimation and compensation would perform equally well or even better than the block matching in terms of motion accuracy, while it results in the coding of global motion model parameters. In this letter, we modify an AVS coder by adding （1） six global motion model parameters to the frame header, and （2） mode selection among INTRA, SKIP, INTER-16×16, INTER-16×8, INTER-8×16, INTER-8×8, and Global Motion Compensation （GMC） modes by Lagrange optimal rate-distortion criteria. Simulation results demonstrate that over 0.1dB improvement in PSNR is obtained compared to the AVS coder for an average coded P-frame with the same bitrate.     

An Airborne Radar Clutter Tracking Algorithm Based on Multifractal and Fuzzy C-Mean Cluster

For an airborne Iookdown radar, clutter power often changes dynamically about 80 dB with wide distributions as the platform moves. Therefore, clutter tracking techniques are required to guide the selection of const false alarm rate （CFAR） schemes. In this work, clutter tracking is done in image domain and an algorithm combining multifractal and fuzzy C-mean （FCM） cluster is proposed. The clutter with large dynamic distributions in power density is converted to steady distributions of multifractal exponents by the multifractal transformation with the optimum moment. Then, later, the main lobe and side lobe are tracked from the multifractal exponents by FCM clustering method.