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31.
本文以tss和MD110联网调试中主波叫通话状态下同时挂机时话路出现“吊死”90s的现象为中心,分析了信令配合过程及产生问题的原因,介绍了解决的办法,提出了两点建议。 相似文献
32.
为了使无线随机网络编码策略更好适用于较大数据量的传输要求,在无线信道的广播特性的基础上加入了将数据分块处理,并考虑了额外开销对信道利用率的影响.通过对分块传输模型的分析,确认信道利用率与分块的大小紧密相关,为了在通信前选择一个适当的分块大小以获得更高的信道利用率,给出了一种计算最优数据块大小的方法.仿真结果表明:该方法简单可行,使用该方法选择数据块大小后,信道利用率将十分接近其上限值. 相似文献
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34.
文中针对公司资产存在的形式多种多样,公司管理人员年底清查资产需要浪费大量宝贵的时间和人力物力,且容易遗漏或重复,实物很难与账面相符的管理情况,设计了一个基于物联网与FRID技术相结合的资产管理系统,在介绍了物联网技术与FRID技术后,详细介绍了该系统的整体架构设计,资产编码设计、RFID标签设计,资产管理系统设计。通过对该系统的实际应用表明,该系统实现了资产系统化、信息化、网络化的管理。对于合理配置和利用资产,降低投入成本,增加投入产出效益,提高管理水平和效率等方面上有着重大的意义。实现了资产管理的信息共享。 相似文献
35.
重点讨论对我国国防信息基础设施的体系结构发展有重大影响的热点技术,介绍了一个超级国防信息系统网络结构建议,以及它的网络功能和应用的军事意义 相似文献
36.
In this paper, we propose a policy-based framework for the management of wireless ad hoc networks and briefly describe a characteristics-based taxonomy that provides a platform to analyze and compare different architectural choices. We develop a solution suite that helps achieve our goal of a self-organizing, robust and efficient management system. One of the main contributions of this work is the prototype implementation and testing of the mechanisms and protocols comprising our framework in a multi-hop ad hoc network environment. Experiments are conducted using both an emulated ad hoc network testbed and a true wireless testbed. Degradation in management system performance is observed as the number of hops between a policy server and client increases. Our proposed k-hop clustering algorithm alleviates this problem by limiting the number of hops between a server and client. We demonstrate the operation of our prototype implementation, illustrating QoS management in a multi-domain ad hoc network environment using the proposed cluster management, redirection, and policy negotiation mechanisms. 相似文献
37.
Stimulating Cooperation in Self-Organizing Mobile Ad Hoc Networks 总被引:24,自引:0,他引:24
In military and rescue applications of mobile ad hoc networks, all the nodes belong to the same authority; therefore, they are motivated to cooperate in order to support the basic functions of the network. In this paper, we consider the case when each node is its own authority and tries to maximize the benefits it gets from the network. More precisely, we assume that the nodes are not willing to forward packets for the benefit of other nodes. This problem may arise in civilian applications of mobile ad hoc networks. In order to stimulate the nodes for packet forwarding, we propose a simple mechanism based on a counter in each node. We study the behavior of the proposed mechanism analytically and by means of simulations, and detail the way in which it could be protected against misuse. 相似文献
38.
To provide responsive information services in a ubiquitous computing environment, service software and system development are indispensable. A component-based ubiquitous information system with a JAIN (Java APIs for Integrated Networks) platform to achieve seamless transmissions and reach-everywhere communications was designed in our research. In this development, numerous ubiquitous service modules were identified: location management, roaming, mobile IP and WAP networking. These component-based network modules were constructed using a component composition language with component specification and interface definition, running on top of a distributed service architecture using a JAIN platform to distribute the ubiquitous information services to mobile users. Two applications, Wireless-Application-Protocol (WAP) Mail and Video-on-Demand (VoD) services, show that the JAIN-like platform with the developed networking components effectively fills the gap for application developers between mobile appliances and various kinds of ubiquitous information services. 相似文献
39.
Optimal Distributed Location Management in Mobile Networks 总被引:4,自引:0,他引:4
Krishnamurthi Govind Azizoğlu Murat Somani Arun K. 《Mobile Networks and Applications》2001,6(2):117-124
An important issue in the design of future Personal Communication Services (PCS) networks is the efficient management of location information. In this paper, we consider a distributed database architecture for location management in which update and query loads of the individual databases are balanced. We obtain lower bounds to the worst-case delay in locating a mobile user, to the average delay, and to the call blocking probability. We then propose a dynamic location management algorithm that meets these lower bounds. The optimality of this algorithm with respect to these three performance measures, as well as simplicity, make it an appealing candidate for distributed location management in PCS networks. 相似文献
40.