分布构件模型技术比较研究

目前的构件模型主要包括CORBA—CCM，EJB和COM／DCOM／COM 三大类。它是基于Web的应用程序开发的核心技术。对这三类构件模型技术的工作机理进行了较详尽的描述，同时对它们之间的关系和优缺点进行了比较研究；最后指出，COM 是开发基于Windows平台应用的有效技术，而CORBA和EJB技术的结合是开发完全与平台无关的Web应用的最佳技术。     

COM/DCOM与CORBA互操作的实现

COM／DCOM和CORBA的异构性决定了COM／DCOM对象和CORBA对象间不可能实现相互通讯。本文应用刚出现的SOAP技术，实现COM／DCOM和CORBA的互操作。     

基于CORBA-JAVA软件复用查询系统中间件技术的研究与实现

分布式对象中间件技术是为了解决分布计算和软件复用过程中存在的异构问题而提出的。CORBA，EJB，COM／DCOM是目前主要的三大中间件技术，它们都有自己的优势应用领域，CORBA和Java的结合在解决Internet www应用方面具有无比的优势，本文介绍了基于Java／CORBA的WWW信息查询系统开发的一般方法。     

关于CORBA与EJB集成模型的研究

分布式对象中间件技术是解决软件复用过程中存在的异构问题和分布式计算而提出来的,目前主要的中间件技术有:CORBA、EJB、COM等,分析了CORBA和EJB各自的优势,在此提出了CORBA和EJB结合来解决WEB应用方面更多的问题,解决两者的互访问题。     

关于CORBA与EJB集成模型的研究

分布式对象中间件技术是解决软件复用过程中存在的异构问题和分布式计算而提出来的,目前主要的中间件技术有:CORBA、EJB、COM等,分析了CORBA和EJ各自的优势,在此提出了CORBA和EJB结合来解决WEB应用方面更多的问题,解决两者的互访问题.     

异构环境下分布组件的对象互操作性的研究

分析了三种目前主要的分布组件模型的特点、体系结构和通信模型。重点讨论了COM／DCOM，CORBA和RMI／EJB三种组件之间的互操作能力，最后给出了一个异构环境下的分布式组件的交互模型。     

EJB组件技术分析

首先介绍了组件技术产生以及发展过程,简略分析了COM,CORBA组件模型,并详细介绍了EJB技术,及其实现方法和各种Bean的功用.     

分布式技术及其应用概述

分布式应用技术是一门新兴的基于网络应用的开发技术，它提供了一种与以往截然不同的网络应用开发模式，实现了高效率、大规模、组件化的分布式程序开发过程.本文首先介绍并比较了分布式技术中目前较为成熟的COM／DCOM、CORBA和EJB技术，然后介绍了新一代的Web Services和网格技术及发展趋势。     

软件复用与EJB构件技术

本文总结了软件复用、构件技术的相关概念,介绍了EJB3.0构件技术开发的架构模型以及构件的类型,最后对当前主流的构件技术标准CORBA、COM、EJB进行了比较。     

基于CCM的软件构件组装技术的研究

OMG在推出的CORBA3．0规范中提出了一个构件模型（CCM）。CORBA构件不仅定义了对外提供的功能，而且还定义了构件所需要的外部功能，使得构件可以利用接口进行组装。同时CCM借鉴了EJB、COM等构件模型的优点，并充分利用了CORBA的开放性。本文在对CORBA构件模型以及模型组装框架中的相关技术进行研究的基础上，努力探索基于CCM的构件组装在系统开发中的应用。     

Intranet／Extranet的安全技术

分析了Intranet/Extranet所面临的安全性问题,介绍了加密技术、信息完整性技术,鉴别交换技术、确认技术、入侵检测技术及访问控制技术等六种基本的安全技术,最后给出一个实例。     

Asymptotic simplifications for hybrid BEM/GO/PO/PTD techniques based on a Generalized Scattering Matrix approach

In this paper we describe a new hybrid weak coupling of asymptotic GO/PO/PTD techniques, Boundary Element Methods (BEM) and Finite Element Method (FEM) based on the FACTOPO Domain Decomposition Methodology (DDM). Thus, the modular domain decomposition approach already assessed with exact techniques such as BEM and FEM is conserved, with the utilization of GO/PO/PTD techniques, resulting in an important reduction of CPU time during parametric studies. As the coupling scheme between asymptotic and exact methods is based on the Lorentz reciprocity theorem, the external structure of the large object is considered perfectly conducting. The accuracy and efficiency of this technique is assessed by performing the computation of the diffraction and radiation by several test-objects in a multi-domain way, cross compared with reference integral equation results.     

Adaptive r and h — r algorithms for boundary elements

The techniques of mesh redistribution (r) and mesh refinement-redistribution (h – r) have been proven to be of considerable practical importance in the numerical solution of boundary value problems. In this paper, the implementation of these techniques in the boundary element formulation is considered. To assess the validity of the proposed algorithms, two model problems are employed. These problems are the potential equation and the equations of linear elasticity in two dimensions, both containing boundary singularities (cracks).     

Nonsmooth H/sub /spl infin// synthesis

We develop nonsmooth optimization techniques to solve H/sub /spl infin// synthesis problems under additional structural constraints on the controller. Our approach avoids the use of Lyapunov variables and therefore leads to moderate size optimization programs even for very large systems. The proposed framework is versatile and can accommodate a number of challenging design problems including static, fixed-order, fixed-structure, decentralized control, design of PID controllers and simultaneous design and stabilization problems. Our algorithmic strategy uses generalized gradients and bundling techniques suited for the H/sub /spl infin// norm and other nonsmooth performance criteria. We compute descent directions by solving quadratic programs and generate steps via line search. Convergence to a critical point from an arbitrary starting point is proved and numerical tests are included to validate our methods. The proposed approach proves to be efficient even for systems with several hundreds of states.     

基于GPU平台的有效字典压缩与解压缩技术

压缩技术被广泛应用于数据存储和传输中,然而由于其内在的串行特性,大多数已有的基于字典的压缩与解压缩算法被设计在CPU上串行执行。为了探究使用图形处理器（graphic processing unit,GPU）对压缩与解压缩过程潜在性能的提升,结合合并内存访问与并行组装的技术,基于CUDA（compute unified device archi-tecture）平台研究了两种并行压缩与解压缩方法：基于字典的无状态压缩和基于字典的LZW压缩。实验结果表明,与传统的单核实现比较,所提方法能够显著改善已有的基于字典的串行压缩与解压缩算法的性能。     

非标准VAX／VMS设备的I／O操作

本文介绍了不同驱动和谐实现ＶＡＸ／ＶＭＳ非标准设备Ｉ／Ｏ操作的方法，即通过映射系统的Ｉ／Ｏ空间、联结设备的中断向量，调用中断服务例程和／或中断后递交的ＡＳＴ例程，实现设备的Ｉ／Ｏ操作。文中给出了实现这种操作的具体步骤。     

E-service design using i* and e/sup 3/ value modeling

Two requirements engineering techniques, i* and e/sup 3/ value, work together to explore commercial e-services from a strategic-goal and profitability perspective. We demonstrate our approach using a case study on Internet radio.     

TCP／IP网络的通信安全技术

该文介绍了基于TCP／IP协议的计算机网络通信安全技术,包括在TCP／IP的网络层、传输层及传输层之上等各个层次中采用密码技术以保证数据的保密性、完整性及可认证性,分析了IPSEC、Secure TCP,SSL等典型的安全协议。     

Robust H/sub /spl infin// and mixed H/sub 2//H/sub /spl infin// filters for equalization designs of nonlinear communication systems: fuzzy interpolation approach

Generally, it is difficult to design equalizers for signal reconstruction of nonlinear communication channels with uncertain noises. In this paper, we propose the H/sub /spl infin// and mixed H/sub 2//H/sub /spl infin// filters for equalization/detection of nonlinear channels using fuzzy interpolation and linear matrix inequality (LMI) techniques. First, the signal transmission system is described as a state-space model and the input signal is embedded in the state vector such that the signal reconstruction (estimation) design becomes a nonlinear state estimation problem. Then, the Takagi-Sugeno fuzzy linear model is applied to interpolate the nonlinear channel at different operation points through membership functions. Since the statistics of noises are unknown, the fuzzy H/sub /spl infin// equalizer is proposed to treat the state estimation problem from the worst case (robust) point of view. When the statistics of noises are uncertain but with some nominal (or average) information available, the mixed H/sub 2//H/sub /spl infin// equalizer is employed to take the advantage of both H/sub 2/ optimal performance with nominal statistics of noises and the H/sub /spl infin// robustness performance against the statistical uncertainty of noises. Using the LMI approach, the fuzzy H/sub 2//H/sub /spl infin// equalizer/detector design problem is characterized as an eigenvalue problem (EVP). The EVP can be solved efficiently with convex optimization techniques.     

Client／Server数据库模型下的并发控制与恢复技术

并发控制与恢复技术在client／server结构DBMS中有着极其重要的地位，直接关系到运行的正确性以及数据库的健壮性。在Client／Server结构中，进行日常事务处理时的首要任务就是保持缓存的一致性，这是进行并发控制的基础。本文详细地分析和研究了Client／SerVer中用到的缓存算法和恢复技术，指出了现有技术存在的不足，并对其发展趋势进行了展望。