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131.
针对雷达信号侦察系统搜索时间长、截获概率低的问题,文中提出了一种基于空域宽开雷达信号侦察系统的搜索调度方法来优化设计驻留时间。根据驻留时间的长短,将驻留时间分为仅能截获单个雷达脉冲的中等驻留时间和可截获多个雷达脉冲的长驻留时间。搜索开始阶段使用较短的中等驻留时间用于频域的快速扫描,在截获信号后将驻留时间调整为长驻留时间,以便采集雷达信号用于频率及周期结构分析。仿真结果表明,提出的算法可合理利用系统资源,提高系统的截获性能,为现有雷达对抗侦察系统设计提供了有益参考。 相似文献
132.
The problem of admission control in a DS-CDMA network carrying a heterogeneous mix of traffic is addressed. In an interference limited system such as DS-CDMA, admission of a new user impacts the performance of all other users, as well as the system capacity. The admission process is concerned with two factors: (1) maintaining the QoS of active users, (2) allocating bandwidth to new users. We propose a simple power control algorithm and prove that it is optimal in the sense of maintaining active link quality while maximizing free capacity for new admissions. The algorithm scales the powers of active links appropriately to achieve link protection and improved tolerance of the link to new interference from bursty sources. This algorithm can be used to overlay bursty packet data services without compromising QoS of active circuits. 相似文献
133.
文中对云计算以及相关的技术内涵等进行了分析,也介绍了虚拟存储技术的相关分类,最终对该项技术在不同领域的应用进行了一定研究,期望能够给该项技术的进一步发展带去一定的帮助。 相似文献
134.
135.
George Dimitrakopoulos Klaus Moessner Clemens Kloeck David Grandblaise Sophie Gault Oriol Sallent Kostas Tsagkaris Panagiotis Demestichas 《Mobile Networks and Applications》2006,11(6):799-811
Users’ expectations towards technology, in terms of quality, service availability and accessibility are ever increasing. Aligned
with this, the wireless world is rapidly moving towards the next generation of systems, featuring cooperating and reconfiguring
capabilities for coexisting (and upcoming) Radio Access Technologies (RATs), so that to improve connectivity and reduce costs.
In this respect, conventional planning and management techniques ought to be replaced by advanced schemes that consider multidimensional
characteristics, increased complexity and high speeds. To this effect, means are needed capable to support scalability and
to cater for advanced service features, provided to users at high rates and cost-effectively. This article provides a scheme
to optimize resource management in future systems, by describing a platform that accommodates engineering mechanisms that
deal with dynamic, demand driven planning and managing of spectrum and radio resources in reconfigurable networks. To do so,
it first discusses the fundamentals and the approach followed in the proposed architecture and then investigates the basic
functional modules. The architecture is validated through a set of use-cases that exemplify the operational applicability
and efficiency in a wide range of communication scenarios.
相似文献
Panagiotis DemestichasEmail: |
136.
浅谈电信运营商的转型 总被引:5,自引:0,他引:5
随着中国电信集团转型口号的正式提出,一时间基础电信运营商的战略转型成为行业关注的热点问题.本文系统地分析了电信运营商转型的必要性和转型的方向,探讨了转型给电信运营商所带来的运营模式和竞争模式的改变等问题.本文认为电信运营商未来运营的核心将是运营一个资源系统,运营商所担当的角色不仅仅是管道提供商,更多的是一个产业链、价值链的管理者和协调者.对于价值链的核心环节,电信运营商必须牢牢控制,而对于非核心的或者辅助性的环节,大可放心地采取外包方式,让更为专业的独立第三方运营. 相似文献
137.
动态重构是一项充分利用软硬件资源的技术。在介绍民机CNS系统和动态重构基本原理基础上,给出了一种动态重构的通用功能模块的设计方案,描述了利用有限状态机和排列组合原理计算系统配置的方法,并根据系统资源状况和应用的优先级对资源进行初次分配及再分配,设计出了一种动态重构算法,该算法能很好地兼顾资源备份式重构和资源抢占式重构。同时,指出对动态重构的品质设计需从可用性、可靠性、维护性方面考虑。最后,使用Simulink对动态重构算法的正确性进行了仿真验证。 相似文献
138.
为推动云计算战略在中国移动的有效落地,中国移动广东公司积极开展云计算应用的研究与验证,并形成了一系列应用成果。本文首先介绍了广东移动对云计算技术应用的整体规划,然后具体讲述广东移动对云计算技术的相关应用实践,包括在虚拟化资源池、终端桌面云以及分布式云计算等领域的应用成果,并对实践经验和应用效果进行了总结,最后对广东移动云计算技术应用的进一步发展和演进进行了展望。 相似文献
139.
Hojung?ChaEmail author Jongmin?Lee Jongho?Nang Sung-Yong?Park Jin-Hwan?Jeong Chuck?Yoo Jin-Young?Choi 《Wireless Networks》2005,11(3):265-274
This paper presents a case of video streaming system for mobile phone which has actually been implemented and deployed for commercial services in CDMA2000 1X cellular phone networks. As the computing environment and the network connection of cellular phones are significantly different from the wired desktop environment, the traditional desktop streaming method is not applicable. Therefore, a new architecture is required to suit the successfully streaming in the mobile phone environment. We have developed a very lightweight video player for use in mobile phone and the related authoring tool for the player. The streaming server has carefully been designed to provide high efficiency, reliability and scalability. Based on a specifically-designed suite of streaming protocol, the server employs an adaptive rate control mechanism which transmits the media packets appropriately into the network according to the change in network bandwidth.Hojung Cha is currently a professor in computer science at Yonsei University, Seoul, Korea. His research interests include multimedia computing system, multimedia communication networks, wireless and mobile communication systems and embedded system software. He received his B.S. and M.S. in computer engineering from Seoul National University, Korea, in 1985 and 1987, respectively. He received his Ph.D. in computer science from the University of Manchester, England, in 1991.Jongmin Lee is a Ph.D. candidiate in computer science at Yonsei University, Seoul, Korea. His research interests include wireless multimedia system, QoS architecture, multimedia communication networks. He received his B.S. and M.S. in computer science from Kwangwoon University in 1999 and 2001, respectively.Jongho Nang is a professor in the Department of Computer Science at Sogang University. He received his B.S. degree from Sogang University, Korea, in 1986 and M.S. and Ph.D. degree from KAIST, in 1988 and in 1992, respectively. His research interests are in the field of multimedia systems, digital video library, and Internet technologies. He is a member of KISS, ACM, and IEEE.Sung-Yong Park is an associate professor in the Department of Computer Science at Sogang University, Seoul, Korea. He received his B.S. degree in computer science from Sogang University, and both the M.S. and Ph.D. degrees in computer science from Syracuse University. From 1987 to 1992, he worked for LG Electronics, Korea, as a research engineer. From 1998 to 1999, he was a research scientist at Telcordia Technologies (formerly Bellcore) where he developed network management software for optical switches. His research interests include high performance distributed computing and systems, operating systems, and multimedia.Jin-Hwan Jeong received the B.S. and M.S. degrees in computer science from Korea University, Seoul, Korea, in 1997, and 1999, respectively. He is currently in Ph.D. course at Korea University. His research interests include video processing for thin devices, multimedia streaming and operating systems.Chuck Yoo received the B.S. degree in electronics engineering from Seoul National University, Seoul, Korea and the M.S. and Ph.D. in computer science in University of Michigan. He worked as a researcher in Sun Microsystems Lab. from 1990 to 1995. He joined the Computer Science and Enginnering Department, Korea University, Seoul, Korea in 1995, where he is currently a professor. His research interests include high performance network, multimedia streaming, and operating systems.Jin-Young Choi received the B.S. degree from Seoul National University, Seoul, Korea, in 1982, the M.S. degree from Drexel University in 1986, and the Ph.D. degree from University of Pennsylvania, in 1993. He is currently a professor of Computer Science and Engineering Department, Korea University, Seoul, Korea. His current research interests are in real-time computing, formal methods, programming languages, process algebras, security, software engineering, and protocol engineering. 相似文献
140.
介绍了UMA系统的基本功能以及不同的视频格式和网络状况给UMA系统带来的失配问题.阐述了在UMA系统中引入MPEG-21的第7部分--数字项改编,来实现资源改编引擎以支持转换编码工具和资源改变引擎QoS的实现,从而解决失配问题. 相似文献