基于消息的离散事件仿真方法

本文提出了一种基于沙息的离散事件仿真方法,它将面向对象的程序设计方法,分布式仿真和并行算法的概念结合在一起,与传统的离散事件仿真方法相比,是一种更加灵活而直观的模型仿真方法。     

一个基于Java的分布式对象应用系统

描述了一个网格应用系统框架,该应用系统以Ｊａｖａ为开发环境,各个功能模块以Ｊａｖａ对象的模式,独立地工作在Ｉｎｔｅｒｎｅｔ的主机上,各功能模块只负责消化处理自己职责范围内的沙息,并把响应沙息发送到网络,因此,各功能模块具有高度的自治性和互动的透明性。     

N-立方体消息通信时延的分析

本文利用生灭过程理论,对Ｎ－立方体的消息通信延时建立了一个计算模型,在存在消息堵塞的情况下对Ｎ－立方体采用虫孔寻径机制和ｅ－ｃｕｂｅ算法时的沙息通信延迟进行了分析求解,最后,通过模拟实验,证明了结果的正确性。     

基于ebXML的消息服务器研究

本文通过对ebXML消息服务以及消息结构进行分析研究,给出了基于ebXML的消息服务器应具有的功能、并提出了其设计原则。最后讨论了消息服务器中关键模块-消息解析器的设计。     

Microsoft Win32消息处理机制及应用编程

Win32消息处理机制是Win32应用编程需要了解的核心内容之一，该文对消息队列、消息发送、消息循环和消息类型进行了深入分析．并列举了几个消息处理机制在编程中的应用。     

基于MOM的消息代理研究与实现

消息代理作为一种以消息进行软件集成的技术,应用越来越广泛。本文对消息代理在软件集成中的作用和使用方式进行了的描述,并提出了一种设计实现方案,包括作为消息代理数据传输基础的消息队列、发布订阅系统和核心部件消息代理器。     

基于信息机制的Windows多任务机理透视

讨论了Windows消息循环的机制,并在与DOS环境中的资源共享进行对比的同时,给出了两个关键的消息机制：键盘消息机制和窗口消息机制的处理流程。最后,对消息机制下多任务的实现以及Windows多任务的控制过程进行了阐述,为Windows程序的开发起到了指导作用。     

云环境下实时消息推送服务构建研究

随着移动互联网技术的发展,各类消息纵横交错,人们在获取关联信息时常感到无从选择。传统的消息获取,用户需要主动拉取网络存储的消息,此种方式获取消息的效率极其低下,会产生众多与用户无关的消息。消息推送需要用户不停地拉取刷新,属于被动推送。随着云技术的发展,消息推送技术逐步转变为云推送,告别了单一服务器推送的模式。对现有各类消息推送技术进行研究和分析,针对传统基于主题订阅模式的消息推送服务只能对应单一移动端通信的不足,提出了云实验环境下实现实时消息推送服务的构建方案,设计了消息推送服务(PushWeb)的运行框架,运用H5技术中的WebSocket技术实现了管理平台和移动客户端应用程序,并将其部署在阿里云中,经测试在良好的网络环境下能够将消息实时准确地推送至移动端。     

MMS系统的体系结构和关键技术的研究

多媒体消息业务(MultimediaMessagingService,MMS)是被3GPP和WAP论坛定义的一种标准的移动信息业务,该文根据国际标准,提出了现阶段的MMS实现方案,论述了MMS业务所涉及的网络功能实体,体系结构以及通信接口的实现方案;详细论述了MMS业务中涉及的关键技术———WAPPush技术,并进行了相关协议分析;最后给出MMS业务中利用非连接Push过程的消息序列图。     

基于JMS的一种消息过滤改进算法

本文分析了JMS发布／订阅模式下传统的消息过滤机制,针对其不能快速处理大量相同或相似消息的缺陷,提出了一种改进的消息过滤算法。通过对所有订阅条件进行预处理来优化匹配结果,在此过程中并对相同或相似订阅条件属性进行处理,从而提高消息匹配效率。     

A real-time messaging system for token ring networks

The Computer Networks Laboratory at the University of Virginia has developed a real-time messaging service that runs on IBM PCs and PC/ATs when interconnected with a Proteon ProNET-10 token ring local area network. The system is a prototype for a real-time communications network to be used aboard ships. The system conforms to the IEEE 802.2 logical link control standard for type I (connectionless, or datagram) service, with an option for acknowledged datagrams. The application environment required substantial network throughput and bounded message delay. Thus, the development philosophy was to emphasize performance initially and to offer only primitive user services. After providing and measuring the performance of a basic datagram service, the intent is to add additional user services one at a time and to retain only those which the user can ‘afford’ in terms of their impact on throughput, delay, and CPU utilization. The current system is programmed in C. The user interface is a set of C procedure calls that initialize tables, reserve buffer space, send and receive messages, and report network status. The system is now operational, and initial performance measurements are complete. Using this system, an individual PC can transmit or receive approximately 200 short (about 100 bytes) messages per second, and the PC/AT operates at nearly 500 short messages per second.     

Pointer variables in concurrent Pascal

Concurrent Pascal and similar languages are inefficient when used to program systems where processes exchange large messages. The inefficiencies, caused by copying of data, can be removed by introducing pointer variables, and this paper shows how this is done without allowing unrestricted sharing of variables. Pointer variables also give means to solve problems of dynamic resource allocation and dynamic addressing. Examples with performance figures for an actual implementation are given.     

CAN报文实时性分析及在线评估

结合CAN总线的位填充机制和最坏情况下的报文延迟时间的数学模型,针对周期性报文,提出基于主节点的报文调度方式,给出了该调度方式下的报文响应时间数学模型．通过CAN总线系统实验平台,对CAN报文的实际长度进行检测和分析,并对符合SAE标准的报文实时性进行了分析和评估．实验表明,基于主节点的调度方式保证了CAN报文的实时性,使得系统具有可调度性．     

MPI_ALLGATHER实现算法的改进与性能分析

首先分析了影响MPI组通信性能的各方面因素,提出了一种衡量算法性能的模型。基于这种分析及模型,提出了一种将邻居交换和递归倍增两种算法结合的新的MPI_ALLGATHER实现算法。新的算法比邻居交换算法通信次数少,比递归倍增算法具有较好的通信局部性。通过在高性能机群系统中的测试,发现新算法在多种情况下比邻居交换算法具有更优的性能,在中等长度消息通信时具有最优的性能,在长消息通信时性能比递归倍增算法和Bruck算法的性能更优,且在长消息通信时多数情况下性能最优。     

基于消息分类的复合模式消息中间件研究

总结消息传递模式和消息队列模式的优缺点，提出一种基于消息分类的复合模式消息中间件设计方案，通过使用最佳的传递模式传递不同需求的消息，提高消息中间件的适用性、灵活性，可以同时满足高速、大数据量数据的传输和可靠持久消息的传输，适用于多种应用领域。     

How to improve snap-stabilizing point-to-point communication space complexity?

A snap-stabilizing protocol, starting from any configuration, always behaves according to its specification. In this paper, we are interested in the message forwarding problem in a message-switched network in which the system resources must be managed in order to deliver messages to any processor of the network. To this end, we use the information provided by a routing algorithm. In the context of an arbitrary initialization (due to stabilization), this information may be corrupted. In Cournier et al. (2009) [1], we show that there exist snap-stabilizing algorithms for this problem (in the state model). This implies that we can request the system to begin forwarding messages without losses even if routing information is initially corrupted.In this paper, we propose another snap-stabilizing algorithm for this problem which improves the space complexity of the one in Cournier et al. (2009) [1].     

Mean value and tail distribution of the message delay in statistical multiplexers with correlated train arrivals

In this paper, we study a statistical multiplexer which is modelled as a discrete-time single-server infinite-capacity queueing system. This multiplexer is fed by messages generated by an unbounded population of users. Each message consists of a generally distributed number of fixed-length packets.

We assume the packet arrival process to exhibit simultaneously the following two types of correlation. First, the messages arrive to the multiplexer at the rate of one packet per slot, which results in what we call a primary correlation in the packet arrival process. Also, on a higher level, the arrival process contains an additional secondary correlation, resulting from the fact that the behaviour of the user population is governed by a two-state Markovian environment. Specifically, the state of this user environment in a particular slot determines the distribution of the number of newly generated messages in that slot.

In previous work on this model, we provided analytical results for the moments and the tail distribution of the system contents. Using these results, we now concentrate on the message delay performance of this system, under the important assumption of a first-come-first-served queueing discipline for packets, whereby packets that arrive during the same slot are stored in random order. Closed-form expressions are derived for the mean value of both the total delay and the transmission time of an arbitrary message. Additionally, we provide a reasonably tight upper and lower bound for the tail probabilities of the message delay. By means of some numerical examples, we discuss the influence of the environment parameters on the delay performance.     

基于Windows消息的软件界面集成技术研究

随着工程规模的扩大,以及软件行业的蓬勃发展,现有工程分析问题经常涉及多个工程软件的交叉使用,软件集成平台的开发成为一个新的研究方向.文章介绍了软件界面集成过程中捕获句柄、利用消息实现程序的控制、消息拦截等关键技术,以及集成平台的实现过程.按照该方法在Visual C#.NET开发环境下实现了Virtual Lab与自行开发的航炮系统集成平台软件的集成,证明了该方法的有效性.文中以机械行业软件集成为例介绍的通用界面集成技术,适用于其他行业软件的集成,甚至跨学科软件集成.     

基于贝叶斯及多模式串模糊匹配算法的不良短信甄别混合模型

手机短信业务一方面给人们带来诸多便利,另一方面不法分子利用短信进行违法犯罪活动也日益猖狂,如何防范和打击此类犯罪活动对执法机关来说是一个新的挑战。提出了一个基于贝叶斯分类算法和改进的多模式串模糊匹配算法的不良短信甄别混合模型,以实现对不良短信的识别和分类。短信经由朴素贝叶斯分类器进行是否不良的判断,对确认为不良的短信再经过多模式串的模糊匹配进行不良类别的分类。实验表明该方法提高了不良短信识别的准确率,具有良好的应用前景和实际效益。重点分析不良短信识别和分类过程。     

拦截Windows传递VB窗口的消息

说明了拦截Ｗｉｎｄｏｗｓ传递给ＶＢ窗口程序的消息的方法,根据拦截消息后常见的３种处理方式,分别给出了一个实际例子。