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11.
城市品格是城市无形层面里最本质的部分。城市品格的塑造需要渗入人文精神和城市特色,这样才能使人们生活得更美好。对镇江而言,要塑造城市品格,就需要立足镇江的历史与现实,结合镇江民众的思考,从功利与超功利的角度进行具体的探索。  相似文献   
12.
通信对抗作战能力评估是解决装备实力比较和兵力规划等问题的前提和基础,如何有效描述通信对抗作战能力,是评估问题的关键所在。根据通信对抗作战能力指标不可公度性的特点,利用效用函数对指标进行描述;并通过对聚合模型的讨论,建立评估模型;最后通过实例验证了利用效用函数法进行通信对抗作战能力评估的可行性和合理性。  相似文献   
13.
In this paper, we address the problem of user-class based service differentiation in CDMA networks. Users are categorized into three classes who get differentiated services based on their expected quality of service (QoS) from the service provider and the price they are willing to pay. We adopt a game theoretic approach for allocating resources through a two-step process. During a service admission, resource distribution is determined for each class. Then, the resource allocated to each class is distributed among the active users in that class. We devise a utility function for the providers which considers the expected revenue and the probability of users leaving their service provider if they are not satisfied with the service. Our model demonstrates how power can be controlled in a CDMA network to differentiate the service quality. Also, we show the impact of admitting high paying users on other users. Mainak Chatterjee received his Ph.D. from the department of Computer Science and Engineering at The University of Texas at Arlington in 2002. Prior to that, he completed his B.Sc. with Physics (Hons) from the University of Calcutta in 1994 and M.E. in Electrical Communication Engineering from the Indian Institute of Science, Bangalore, in 1998. He is currently an Assistant Professor in the department of Electrical and Computer Engineering at the University of Central Florida. His research interests include economic issues in wireless networks, applied game theory, resource management and quality-of-service provisioning, ad hoc and sensor networks, CDMA data networking, and link layer protocols. He serves on the executive and technical program committee of several international conferences. Haitao Lin received the BE degree in radio engineering from Southeast University, Nanjing, China, in 1996, the MS degree in computer applications from the Beijing University of Posts and Telecommunications, Beijing, China, in 2000, and Ph.D. in Computer Science and Engineering from The University of Texas at Arlington in 2004. He is currently with Converged Multimedia Services System Engineering at Nortel, Richardson, Texas. His research interests include wireless network performance evaluation and enhancement, wireless link adaptation, wireless network resource management, and applied game theory. Sajal K. Das received B.S. degree in 1983 from Calcutta University, M.S. degree in 1984 from Indian Institute of Science, Bangalore, and Ph.D. degree in 1988 from University of Central Florida, Orlando, all in Computer Science. He is currently a Professor of Computer Science and Engineering and also the Founding Director of the Center for Research in Wireless Mobility and Networking (CReWMaN) at the University of Texas at Arlington (UTA). Prior to 1999, he was a professor of Computer Science at the University of North Texas (UNT), Denton where he founded the Center for Research in Wireless Computing (CReW) in 1997, and also served as the Director of the Center for Research in Parallel and Distributed Computing (CRPDC) during 1995–97. Dr. Das is a recipient of the UNT Student Association's Honor Professor Award in 1991 and 1997 for best teaching and scholarly research; UNT's Developing Scholars Award in 1996 for outstanding research; UTA's Outstanding Faculty Research Award in Computer Science in 2001 and 2003; and the UTA College of Engineering Research Excellence Award in 2003. He is also frequently invited as a keynote speaker at international conferences and symposia. Dr. Das' current research interests include mobile wireless communications, resource and mobility management in wireless networks, mobile and pervasive computing, wireless multimedia, ad hoc and sensor networks, mobile internet architectures and protocols, distributed and grid computing, performance modeling and simulation. He has published over 350 research papers in these areas in international journals and conferences, directed numerous industry and government funded projects, and holds five US patents in wireless mobile networks. He received four Best Paper Awards in the ACM MobiCom'99, ICOIN'01, ACM MSWiM'00, and ACM/IEEE PADS'97. He as the Editor in Chief of the Pervasive and Mobile Computing (PMC) journal and also as an Associate Editor of IEEE Transactions on Mobile Computing, ACM/Kluwer Wireless Networks, Parallel Processing Letters, Journal of Parallel, Distributed and Emerging Systems. He served as General Chair of IEEE WoWMoM'05, PerCom'04, IWDC'04, MASCOTS'02, ACM WoWMoM'00-02; General Vice Chair of IEEE PerCom'03, ACM MobiCom'00 and IEEE HiPC'00-01; Program Chair of IWDC'02, WoWMoM'98-99; TPC Vice Chair of ICPADS'02; and as TPC member of numerous IEEE and ACM conferences. He is Vice Chair of the IEEE Computer Society's TCPP and TCCC Executive Committees.  相似文献   
14.
Utility based resource allocation strategy in multi-cell orthogonal frequency-division multiplexing (OFDM) system plays a critical role in next generation mobile communication systems. Based on the analysis of risk aversion utility functions, this article proposed the system utility based utility, which is named the customer satisfaction (CS) utility. Compared with the proportional fairness (PF) utility, the CS utility reflects the user demands better, and enables the system to adjust its resource allocation according to both the traffic requirements and the resource situation.  相似文献   
15.
在对"流"公平的CSFQ(Core-Stateless Fair Queueing)算法基础上进行改进,将算法设计思想由对流速率的公平分配改为对表征用户需求的效用函数的公平分配,从而提出一种对用户公平的核心无状态队列管理算法(Core-Stateless User Fair Queueing,CSUFQ),该算法能近似实现边界及核心路由器上对用户需求的最大最小公平,仿真实验证明了其效果.  相似文献   
16.
支持CE的T—MPLS关键技术及应用   总被引:1,自引:0,他引:1  
传送多协议标记交换(T—MPLS)作为一种面向连接的分组传送技术,是支持电信级以太网(CE)的主要承载技术。从T—MPLS技术特性入手,文章介绍了T—MPLS标准化的最新进展及其面临的挑战,给出T—MPLS作为CE承载技术的组网模型,在此基础上,讨论了与T—MPLS有关的数据转发平面,控制平面,网络生存性,操作、维护和管理(OAM)等关键技术,分析了基于T—MPLS的CE技术的应用情况。  相似文献   
17.
软件定义网络(SDN)采用控制和转发的分离架构,使研究者可以通过软件实现任意的网络控制逻辑,而不需对网络设备本身进行修改,具备极强的灵活性,已经在路由决策、网络虚拟化、无线接入、云计算数据中心网络等领域得到研究和应用,成为一项热点技术。但SDN在蓬勃发展的同时,也引入了新的安全风险,带来新的安全问题。另一方面,SDN也给传统安全技术以冲击,带来创新的网络安全应用发展的机会。鉴于此,结合SDN网络架构的特点综述了SDN安全的研究现状,包括SDN安全风险分析和安全技术及应用,并思考了SDN对信息安全的意义。  相似文献   
18.
资源分配是移动容迟容断网络的核心问题之一,影响着容迟容断网络路由甚至整个系统的效率.然而目前移动容迟容断网络的资源分配策略大多基于神经网络和遗传算法的混合算法,计算量大,不利于实时应用.为此根据移动网络可预测环境,提出了接入路由器消息矩阵及准二维接入带宽的约束条件,在此基础上建立了基于效用函数的资源分配策略,以满足实时要求.算法具有O(n)的算法复杂度,仿真结果显示切换掉话率和新呼叫阻塞率仅比最优化算法升高约1/4,计算用时则只有其36.99%.说明其在保证实时性的前提下仍能提供较好的QoS.算法可以进一步推广到二维移动场景中.  相似文献   
19.
针对MPLS技术在运营商应用中存在问题的分析,结合SDN思想和概念,将网络抽象为“网络转发”、“业务控制”和“运营支撑”三个平面,提出端到端无缝MPLS组网的解决方案。  相似文献   
20.
实用新型创造性判断中,现有技术的领域是判断现有技术是否给出了“技术启示”的重要考虑因素,如何认定“相近或相关的技术领域”往往成为争论的焦点.本文基于专利法和审查指南的相关规定,通过对一个典型案例的分析,得出基于产品的功能原理和现有技术的内在关联性,来认定现有技术是否属于“相近或相关的技术领域”.  相似文献   
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