长城加油卡网络管理系统架构的设计与实现

简要介绍发长城加油卡管理系统的系统结构和功能,以及通信网络平台的网络拓扑结构,系统采用ＴＣＰ／ＩＰ协议与Ｃｌｉｅｎｔ／Ｓｅｒｖｅｒ框架,实现了在金融领域中控环境与小型机环境之间异种网ＴＣＰ／ＩＰ互联的网络解决方案。     

CAD／CAPP／MRPⅡ／GT信息集成的探讨

实现ＣＩＭＳ的关键技术之一是动态信息集成。本文论术字一ＣＩＭＳ系统中ＣＡＤ／ＣＡＰＰ／ＭＲＰⅡ／ＧＴ之间的信息集成技术及其实现方法,提出了在ＣＡＤ系统中通过建立与工艺设计工步内容相匹配的、基于设计基本特征和工艺基本特征的特征建模技术及处理来实现ＣＡＤ／ＣＡＰＰ之间信息共享的方法;论述了ＣＡＰＰ系统通过与ＭＲＰⅡ系统中工艺路线管理模式块之间信息传递来实现并行ＣＡＰＰ设计的步骤,提出了ＧＴ与ＭＲＰⅡ之     

TCP／IP通信协议探讨

本文详细介绍了ＴＣＰ／ＩＰ协议的内容,并讨论了ＴＣＰ／ＩＰ协议的分层结构和ＴＣＰ／ＩＰ的几个协议。除此之外,总结了ＴＣＰ／ＩＰ协议的特点,并指出了讨论ＴＣＰ／ＩＰ协议的意义。     

Windows TCP／IP平台上MMS通信系统研究与实现

Ｗｉｎｄｏｗｓ ＴＣＰ／ＩＰ是当今流行的应用和开发平台。ＭＭＳ（制造报文规范）是计算机网络应用层的重要标准之一，适合于ＣＩＭＳ和自动化系统通信。本文首先介绍ＭＭＳ协议规范和Ｗｉｄｎｏｗｓ ＴＣＰ／ＩＰ开放系统平台，接着探讨了在Ｗｉｎｄｏｗｓ ＴＣＰ／ＩＰ平台上开发ＭＭＳ通信系统的方法和步骤，最后给出ＭＭＳ通信系统实现流程。     

机械CAD软件精品XTMCAD

机械ＣＡＤ软件精品ＸＴＭＣＡＤ公司产品ＸＴＭＣＡＤ特征化参数化集成机械ＣＡＤ／ＣＡＰＰ／ＣＡＭ系统板金ＣＡＤ／ＣＡＰＰ／ＣＡＭ系统模具ＣＡＤ／ＣＡＭ冷冲模ＣＡＤ／ＣＡＭ数控冲床、铣床、线切割图形自动编程系统图纸光栅、矢量混合编辑及矢量化系统工程图纸光...     

信息窗

信息窗ＭＤＴＶ公司的ＣＡＤ／ＣＡＥ／ＣＡＭ软件及技术广泛应用于中国汽车工业在机械工业部主办的一年一度的大型国际汽车展览会上，法国ＭＤＴＶ公司展出了他们最新的ＣＡＤ／ＣＡｎ／ＣＡＭ系统产品和技术。他们在７台工作站和微机上同时演示人们熟悉的ＥＵＣＬＩＤ、...     

利用CATV电缆构造局域网技术的探讨

针对目前ＣＡＴＶ非常普及的情况，本文提出了利用现有的ＣＡＴＶ系统组建宽带局域网的建议，同时讨论了其改造实现技术，提出了一种新的ＣＳＭＡ／ＣＤ的实现方法，并初步分析了该系统的性能和应用前景。     

与MDT无缝集成的MoldCreator

ＭｏｌｄＣｒｅａｔｏｒ是以色列Ｒ＆Ｂ公司设计开发的产品,由于Ｒ＆Ｂ公司与Ａｕｔｏｄｅｓｋ公司为ＭＡＩ合作伙伴,这样,ＭｏｌｄＣｒｅａｔｏｒ就与ＭＤＴ一起,为企业提供了基于ＭＤＴ的ＣＡＤ／ＣＡＥ／ＣＡＭ一体化解决方案。 ＭｏｌｄＣｒｅａｔｏｒ与 ＭＤＴ之间的无缝集成,使用户不仅可以充分享受到ＭＤＴ软件的设计建模的强大功能,同时也使二者可以在同一个界面下进行造型、局部细化设计和模架的设计工作,从而避免了ＣＡＤ系统与模具设计系统之间的数据交换和传输,这就大大简化了设计者的工作,也避免了易出现问题的数据传…     

利用CATV电缆线构造局域网

针对目前ＣＡＴＶ非常普及的情况，提出了利用现有的ＣＡＴＶ系统组建宽带局域网的建议，同时讨论了其改造和实现的技术，并提出了一种新的ＣＳＭＡ／ＣＤ的实现方法，初步分析了该系统的性能和应用前景。     

可转位刀片三维断屑槽CAT／CAD／CAM系统

本文阐述了一个可转位刀片三维断槽测量，设计与制造的有关，实用的ＣＡＴ／ＣＡＤ／ＣＡＭ系统，并对该开发系统各部分结构和功能进行了简介。     

基于三层网络架构及DOM的XML系统模型

本文阐述如何在三层网络架构上运用XML以构造XML文档支持系统,提出了基于三层网络架构及DOM的XML系统的模型,该系统与传统的客户／服务器应用或是应用一般的数据传输方式如HTML等系统相比具有减少了网络流量、更有利于检索、可从多种不同的数据源集成数据、开放性、可扩充性、可重用性等一系列特点。     

A high performance hybrid SSVEP based BCI speller system

The existing EEG based keyboard/speller systems have a tradeoff between the target detection time and classification accuracy. This study focuses on increasing the accuracy and probability of target classification rates in the SSVEP based speller system. We proposed two different types of hybrid SSVEP system by combining SSVEP with vision based eye gaze tracker (VET) and electro-oculogram (EOG). Thirty six targets were randomly chosen for this study and their corresponding visual stimulus was presented with unique frequencies. The visual stimuli were segregated into three groups and each group were arranged into different regions (left/middle/right) of the keyboard/speller layout for improving the probability of target detection rate. The VET/ EOG data were utilized to identify the regions that belong to the selected target. The region/group determination decreases the issue of misclassification of SSVEP frequencies. The averaged spelling accuracies of SSVEP-VET and SSVEP-EOG system for all the subjects is 91.2% and 91.39% respectively. Later, a visual feedback was added to the SSVEP-EOG system (SSVEP-EOG-VF) for improving the target detection rate. In this case, an average classification accuracy of 98.33% was obtained with the information transfer rate (ITR) of 69.21 bits/min for all the subjects. An accuracy of 100% was obtained for five subjects with the ITR of 74.1 bits/min in this system.     

Dynamic queue level control of TCP/RED systems in AQM routers

One main TCP congestion control objective is, by dynamically adjusting the source window size according to the router queue level, to stabilize the buffer queue length at a given target, thereby achieving predictable queueing delay, reducing packet loss and maximizing link utilization. One difficulty therein is the TCP acknowledging actions will experience a time delay from the router to the source in a TCP system. In this paper, a time-delay control theory is applied to analyze the mechanism of packet-dropping at router and the window-updating in TCP source in TCP congestion control for a TCP/RED dynamic model. We then derive explicit conditions under which the TCP/RED system is asymptotically stable in terms of the instantaneous queue. We discuss the convergence of the buffer queue lengths in the routers. Our results suggest that, if the network parameters satisfy certain conditions, the TCP/RED system is stable and its queue length can converge to any target. We illustrate the theoretical results using ns2 simulations and demonstrate that the network can achieve good performance and converge to the arbitrary target queues.     

Network model and effective evolutionary approach for AGV dispatching in manufacturing system

Automated guided vehicles (AGVs), are the state-of-the-art, and are often used to facilitate automatic storage and retrieval systems (AS/RS). In this paper, we focus on the dispatching of AGVs in a flexible manufacturing system (FMS). A FMS environment requires a flexible and adaptable material handling system. We model an AGV system by using network structure. This network model of an AGV dispatching has simplexes decision variables with considering most AGV problem’s constraints, for example capacity of AGVs, precedence constraints among the processes, deadlock control. Furthermore, these problems can be solved by using a lot of heuristic algorithms as network optimization problems. We are also proposed an effective evolutionary approach for solving a kind of AGV’s problems in which minimizing time required to complete all jobs (i.e. makespan) and minimizing the number of AGVs, simultaneously. For applying an evolutionary approach for this multicriteria case of AGV problem, priority-based encoding method and Interactive Adaptive-weight GA (i-awGA) were proposed. Numerical analyses for case study show the effectiveness of proposed approach. Received: June 2005 / Accepted: December 2005     

A Wireless Instructor System for Computer-Supported Collaborative Learning Requiring Immersive Presence (CSCLIP)

The Computer-Supported Collaborative Learning Requiring Immersive Presence (CSCLIP) concept has been established with the objective of extending and enhancing thee-learning experience of distance education, especially for classes that involve laboratory (lab) experiments. The CSCLIP concept defines immersive presence as an inherent requirement that enables cognitive, affective, and most importantly psychomotor learning objectives to integrate into designs and concepts for next generation e-learning systems (Sharda et~al., 2003). Within the CSCLIP architectural framework, the Wireless Instructor (WI) system has been conceptualized and developed as an essential device to effectively support teaching while roaming instructional features for both local and distance students. The WI system provides cost effective means to establish a real-time immersive presence for the distance learning (DL) student and his/her lab group peers. The technical design and system architecture to create a WI system are introduced in this paper. The objective of the WI system is to make the learning experience more vivid and interactive by enabling the DL students, as well as the local students that are not in the same room with the instructor(s) at the same time, to be able to flexibly interact with the instructor(s) in real-time. With this system the students can experience real-time or non-real-time virtual tours with the instructor(s), enabling the students to visit places that may not be easily accessible due to distance, limited space and/or time, cost, or possible danger. The WI system consists of two major sub-components. First is a wireless audio and video (AV) system, which transfers real-time AV signals to and from the instructor(s) to all students. Second is the wireless instructor locator & data assistant system. These two systems can be combined into one WI unit, but as the applied development technologies are somewhat distinct, their features and architectural designs will be described separately throughout this paper. Integration of the two systems will enable further capabilities.This revised version was published online in March 2005 with corrections to the cover dateThis project was funded by the U.S. Department of Education (DoE) award no. P116Z020042 project titled Telecommunications Virtual Laboratory Development.     

面向嵌入式系统的优化编译器生成器设计

构造嵌入式系统是一个硬件软件的协同设计问题 .嵌入式软件的有效开发需要相应编译器的支持 .由于嵌入式系统存储空间有限 ,所以编译器生成的机器代码必须非常紧凑 .我们可以使用编译器的生成器来提高编译器的开发效率 .本文给出了一种编译器生成器的设计原理 ,利用该编译器生成器可以迅速生成面向某种指令系统和机器特征 ,并且能够对输出代码进行自动紧凑的编译器     

基于关系型数据库的CA系统

当PKI技术应用于企业或政府信息化时，它必须与其它业务系统集成。采用与业务系统相一致的关系型数据库，有利于不同系统的集成。当CA系统采用关系型数据库和浏览器／Web应用服务器／数据库服务器3层结构时，证书相关信息的查询可以通过HTTP协议简单实现，LDAP和OCSP引擎可以使系统与标准协议保持兼容。另外，在这种结构下，通过引入基于关系型数据库的角色、权限管理机制，可以大大简化CA/RA的管理，使系统的运行和维护更加容易。     

基于HLA结构的分布交互仿真的系统设计问题

对基于HLA/RTI结构的分布交互式多机仿真系统的体系结构、底层通信网络、运行支持系统、仿真应用对象模型和管理对象模型进行了论述,旨在为分布仿真应用系统的开发探索一条有效途径。     

ABC/ADL:一种基于XML的软件体系结构描述语言

作为基于构件的软件开发过程的系统蓝图,软件体系结构(SA)扮演了非常重要的角色,其研究受到越来越多的关注．而软件体系结构描述语言(ADL)是研究和应用SA的基础．提出了一种基于XML的体系结构描述语言——ABC／ADL．ABC／ADL具备大多数ADL描述软件系统高层结构的能力,还支持系统的逐步精化与演化,并支持系统的自动化组装和验证．采用数据互操作标准XML作为元语言,不仅使ABC／ADL具有与其他ADL的互操作性,还有助于实现设计阶段的制品与其他软件生命周期阶段制品之间的可追踪性．     

Mapping Wireless Communication Algorithms onto a Reconfigurable Architecture

Future mobile communication systems have to be flexible while adapting to environmental conditions and user demands. These systems also have to be energy-efficient as they are used in battery-operated terminals. We expect that heterogeneous reconfigurable hardware can overcome the contradicting requirements in flexibility, energy-efficiency and performance. A coarse-grain reconfigurable processor, called MONTIUM, is presented. An overview of a wireless LAN communication system, HiperLAN/2, and a Bluetooth communication system will be given. Possible implementations of these systems in heterogeneous reconfigurable hardware are discussed. Performance figures of the implemented HiperLAN/2 baseband processing in the MONTIUM architecture are presented. The required performance can be obtained at low clock frequencies with small configuration overhead. The flexibility of the MONTIUM is shown, as the baseband processing of both HiperLAN/2 and Bluetooth is implemented on the same architecture.