A PRECONDITIONER FOR DOMAIN DECOMPOSITION METHODS WITH MORTAR LAGRANGE MULTIPLIE

In this paper we consider the domain decomposition methods with mortar element Lagrange multipliers to two-dimensional elliptic problems.We shall construct a kind of simple preconditioners for the corresponding interface equation.It will be shown that condition number of the preconditioned interface matrix is almost optimal.     

A PRECONDITIONER FOR DOMAIN DECOMPOSITION METHODS WITH MORTAR LAGRANGE MULTIPLIERS

In this paper we consider the domain decomposition methods with mortar element Lagrange multipliers to two-dimensional elliptic problems. We shall construct a kind of simple preconditioners for the corresponding interface equation. It will be shown that condition number of the preconditioned interface matrix is almost optimal.     

Preliminary Discussion on the Relationship Between EM Wave Propagation Characteristics and Medium Parameters in Anisotropic Medium

The reflection and transmission characteristics of an anisotropic half-space medium normally illuminated by a plane wave are analyzed by kDB coordination. The general formula of reflection coefficient at the air-medium interface is given, and its validity is also discussed. The possible propagating modes in different mediums and the effect of medium parameters on these modes are emphatically studied. This work provides the theoretical preparations for the parameter reconstruction of an anisotropic material.     

Interior penalty bilinear IFE discontinuous Galerkin methods for elliptic equations with discontinuous coefficient

<正> This paper applies bilinear immersed finite elements (IFEs) in the interior penalty discontinuousGalerkin (DG) methods for solving a second order elliptic equation with discontinuous coefficient.A discontinuous bilinear IFE space is constructed and applied to both the symmetric and nonsymmetricinterior penalty DG formulations.The new methods can solve an interface problem on a Cartesianmesh independent of the interface with local refinement at any locations needed even if the interfacehas a nontrivial geometry.Numerical examples are provided to show features of these methods.     

New design and analysis of finite difference domain decomposition algorithm for the two-dimensional heat equation

<正> It is presented in this paper that the new design and its analysis of finite difference domaindecomposition algorithms for the two-dimensional heat equation,and the numerical results have shownthe stability and accuracy of the algorithms,where Saul'yev asymmetric schemes have been used atthe interface points.The Algorithm Ⅱ in this paper has further extended those developed by Dawsonand the others,Zhang and Shen.     

Designing cost-effective network-on-chip by dual-channel access mechanism

A dual-channel access mechanism to overcome the drawback of traditional single-channel access mechanism for network-on-chip (NoC) is proposed.In traditional single-channel access mechanism,every Internet protocol (IP) has only one channel to access the on-chip network.When the network is relatively idle,the injection rate is too small to make good use of the network resource.When the network is relatively busy,the ejection rate is so small that the packets in the network cannot leave immediately,and thus the probability of congestion is increased.In the dual-channel access mechanism,the injection rate of IP and the ejection rate of the network are increased by using two optional channels in network interface (NI) and local port of routers.Therefore,the communication performance is improved.Experimental results show that compared with traditional single-channel access mechanism,the proposed scheme greatly increases the throughput and cuts down the average latency with reasonable area increase.     

A High Speed Signal Processing Machine -Its Architecture, Language and Compiler

A systolic array architecture computer (FXCQ) has been designed for signal processing. R can handle floating point data at very high speed. It is composed of 16 processing cells and a cache that are connected linearly and form a ring structure. All processing cells are identical and programmable. Each processing cell has the peak performance of 20 million floating-point operations per second (20MFLOPS). The machine therefore has a peak performance of 320 M FLOPS. It is integrated as an attached processor into a host system through VME bus interface. Programs for FXCQ are written in a high-level language -B language, which is supported by a parallel optimizing compiler. This paper describes the architecture of FXCQ, B language and its compiler.     

The Studies of Some Key Technologies in Magnetic Disk Drives

This paper introduces some final results of some key technologies in magnetic disk drives. We dicuss the design and experiment of thin film head, magnetic fluid exclusion seal system, head disk interface and the engineering appilcations of these technologies in magnetic disk drives.     

Exponential stability for cellular neural networks: an LMI approach

A new sufficient conditions for the global exponential stability of the equilibrium point for delayed cellular neural networks （DCNNs） is presented. It is shown that the use of a more general type of Lyapunov-Krasovskii function enables the derivation of new results for an exponential stability of the equilibrium point for DCNNs. The results establish a relation between the delay time and the parameters of the network. The results are also compared with one of the most recent results derived in the literature.     

Channel Mismatching in Sidelobe Canceler: Limitations and Remedies

After a brief recall of the Sidelobe Canceler (SLC) working principle, including the derivation of a general formula for the Cancellation Ratio (CR), the effects of channel mismatching are investigated. In particular, curves providing CRvalues as a function of amplitude and phase channel mismatching, radar bandwidth, and jammer direction of arrival (JDOA) are provided for the cases of one and two auxiliary antennas. Subsequently, a time -space processor for performance restoration is analyzed in detail. In addition to the above mentioned quantities, the attainable CR value is expressed as a function of the space-time processor parameters. The contribution of the paper is related to the derivation of a number of mathematical equations of CR for several cases of practical interest for the radar engineer. In addition, several curves are presented to assist design of SLC systems.     

CADCSC软件系统人机界面设计

本文论述了CADCSC软件系统的界面设计。提出了适合各种用户的、由多种交互方式组成的混合人机交互界面;为控制系统的计算机辅助设计提供了统一的命令表达方式和统一的运行界面;介绍了其中界面设计一致性与灵活性。     

MIS用户界面设计中面向对象技术的应用

高层管理信息系统涉及的信息类型多、结构复杂，对用户界面的要求高。常用的关系型数据库管理系统所提供的图形设计能力很弱，影响了系统开发工作的效率。在一个实际系统的设计中，我们采用面向对象技术分析用户界面，定义出界面的各种对象和信息模型，提高了图形用户界面程序的可重用性，缩短了系统开发周期.     

EAST装配仿真的三维交互和用户界面设计

EAST装配仿真是典型的大型机械装置的装配仿真，规划其复杂几何部件的装配路径需要提供较好的用户界面和三维交互环境。传统的三维交互、用户界面设计已经不适合EAST装配仿真。本文首先简单介绍了大型机械装置EAST的装配特点和系统设计思想，然后提出了高架行车的运动模型、用户界面模型和多三维视景的构造方法。最后通过高架行车拟实控制、多三维视景环境、视景与控制界面相分离的实现创建了自然、高效的EAST装配仿真用户界面和三维交互环境。     

采用真雷达显示器的航海雷达模拟器的关键技术

传统的雷达模拟器大致可分为全微机化的雷达模拟器及采用真雷达显示器和雷达信号发生器板的雷达模拟器。第一种雷达模拟器的操作界面逼真度尚待进一步提高，第二种雷达模拟器由于受雷达信号发生器板内存等限制，所能模拟的海区不如第一种雷达模拟器多，灵活性欠佳。本文的雷达模拟器采用微机生成雷达视频信号，通过雷达接口板将由计算机模拟的不同海区雷达回波图像显示在真雷达显示器上，具有灵活性大、逼真度高的特点。对该雷达模拟器的几个关键技术：雷达不同显示方式下的坐标变换、岸线回波生成算法、雷达信号接口板的的设计作了详尽介绍。该接口板可产生满足雷达／ARPA显示设备需要的各种信号，并可实时将计算机模拟的雷达视频数据转换成雷达显示设备可以接收的雷达回波信号，显示在真实雷达显示设备上。成功地应用在全任务大型船舶操纵模拟器中。     

基于场景的虚拟环境用户界面研究及实现

虚拟环境用户界面是人与虚拟环境交互的工具也是虚拟现实的重要组成部分之一。传统的用户界面模型都是基于命令而非基于用户意图，结果与需要用户频繁的地虚拟环境和界面来回归换，从而找断用户设计思路或破坏用户的情景感受。本文给出一个基于场景的虚拟环境用户界面的模型，并结合虚拟装配应用实例验证该模型及实现方法。     

用PLD构成高速RS—485同步总线接口

在复杂的主从多点系统中，以微机为核心的各站之间的高速数据交换是必不可少的重要环节。本文介绍了用可编程逻辑阵列芯片实现ＲＳ－４８５高速串行同步通信的一种设计方法。所设计的接口电路克服了用标准接口芯片实现的接口电路中存在的一些问题，如死机、丢帧、传输数据率低及收发占用机时过长等问题。通过在实际系统中的大量检验，证明本文的设计思想具有较高的实用价值。     

基于TCP/IP协议的图像传输网络接口的设计与实现

网络接口对于图像在局域网或因特网中传输起着关键作用。讨论了基于TCP/IP协议用于网络相机的网络接口,采用MAC控制器芯片和51单片机,实现了一种实用的、低成本的网络接口方案。给出了网络接口的硬件组成框图。针对具体的网络相机应用背景,讨论了接口相关协议的实现方法以及基于Winsock的编程接收,并对通过UDP协议传输图像时丢包和包失序现象产生的原因及处理方法进行了探讨。最后给出了在局城网环境下的实验结果。     

界面矛盾运动规律的逻辑推演

界面矛盾形成原因以及界面矛盾运动规律的探索，是解决系统内部界面矛盾与冲突的两个基本前提。通过逻辑推理，推演出界面矛盾的运动规律曲线，将界面矛盾运动和发展过程分为五个阶段，即创立期、分歧期、磨合期、平稳期和危机期，并对各个阶段的矛盾属性、表现特征和主要原因进行了阐述，最后从哲学思辨的角度，论述了界面矛盾运动规律研究对界面管理的启示。