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1.
面向服务的综合电子信息系统软件策略   总被引:1,自引:0,他引:1  
针对SOA在综合电子信息系统中的应用,介绍了SOA的概念,分析了应用需求,研究了基于SOA的系统软件结构和主要特征;从标准化、构件化、工具化、数据模型、服务总线、治理和管理等方面提出了SOA软件发展策略;探索了SOA软件的实现方法.  相似文献   

2.
2012年是华平股份发展至关重要的一年,公司在市场、销售、产品等方面都取得了较大的发展。 市场方面,华平股份对公司团队进行了调整和优化,扩充了技术研究和市场销售队伍,完善了总部、7个大区(华东、华中、华南、西北、西南、东北),31个办事处的三级架构模式,实现了服务网络的全国全覆盖,有效地保障了客户服务要求的响应时间和服...  相似文献   

3.
采用发光二极管的液晶投影机的设计   总被引:2,自引:0,他引:2  
华锋  冉旭  于恒 《液晶与显示》2008,23(3):365-370
利用红、绿、蓝三个发光二极管(LED)作为液晶投影机的光源,设计了包括发光二极管、集光透镜组、偏振光转化器、积分透镜、场透镜、偏光板、十字合成棱镜,以及1.40 cm(0.55 in)液晶板的新型照明系统的光学引擎.比较了LED投影机与目前超高压汞灯投影机两种光学引擎技术,讨论了LED投影机的发光效率、光谱特性,并测量了样机的照度、对比度.测量结果达到了设计目标.  相似文献   

4.
基于FPGA动态显示乐曲演奏器片上系统的分析与设计   总被引:1,自引:0,他引:1  
杨国庆 《现代电子技术》2006,29(19):162-164
分析了乐曲演奏设计中音符、频率、节拍、显示与编码的相互关系,并在EDA开发工具QuartusⅡ平台上,采用VHDL语言层次化和模块化的设计方法,通过音符编码的设计思想,实现了基于FPGA片上系统(SoC)动态显示乐曲演奏器的设计,使乐曲演奏数字电路设计得到了更好的优化,同时减少了设计芯片的数量、缩小了体积、降低了功耗、提高了设计的灵活性、可靠性和可扩展性。  相似文献   

5.
制约物联网发展的因素研究   总被引:2,自引:0,他引:2  
龙燕  韦运玲 《广东通信技术》2010,30(12):40-42,58
介绍了物联网的发展背景,阐述了物联网的体系结构和核心技术,介绍了物联网的应用领域,并详细地从标准、技术、安全、IP地址、市场、产品开发难度等方面详细研究了制约物联网的发展因素。  相似文献   

6.
丁森华 《电视技术》2012,36(14):28-32
介绍了数字家庭相关背景和发展历程,分析了其网络化、信息化、智能化、安全性和一体化服务5个方面的要求,并重点介绍了OSGi、DLNA、闪联、e家佳等主要标准,列举了基于各标准的典型应用,最后对数字家庭发展的方向进行了总结。  相似文献   

7.
"5·12"汶川特大地震,震级之高、破坏之大、波及之广、营救之难均超过了唐山大地震,给四川灾区带来了巨大的破坏,造成了严重的人员和财产损失.但是四川人民并没有被突如其来的灾难吓倒,而是团结一心、坚忍不拔、努力自救,展示了四川人能够吃大苦、耐大劳、百折不挠、勇于担当的崇高精神,受到了舆论的普遍赞扬,感动了中国,感动了世界.  相似文献   

8.
环氧塑封料的性能和应用研究   总被引:3,自引:0,他引:3  
介绍了环氧塑封料的国内外发展概况,着重论述了其物理性能、机械性能、热性能、导热性能、电性能、化学性能、阻燃性能、贮存性能、封装性能,以及应用中封装工艺、缺陷的解决办法,并就发展前景发表了自己的看法.  相似文献   

9.
介绍了数字家庭相关背景和发展历程,分析了其网络化、信息化、智能化、安全性和一体化服务5个方面的要求,并重点介绍了OSGi、DLNA、闪联、e家佳等主要标准,列举了基于各标准的典型应用,最后对数字家庭发展的方向进行了总结.  相似文献   

10.
ZigBee技术具有低功耗、低成本、低速率、近距离、短时延、大容量、高度安全等优势,成为极具竞争力的新兴技术。文章首先给出了ZigBee的标准化组织和现状,介绍了ZigBee的特点,研究了ZigBee的协议栈结构,分析了ZigBee的网络构成,比较了ZigBee不同的网络拓扑结构,最后讨论了ZigBee的应用领域。  相似文献   

11.
龚强 《信息技术》2005,29(9):1-5
网格的本质特征主要是低成查高效能、安全性更可靠、异构整合调度;一般物理特征具有充分共享性、虚拟抽象性、有机集成性和合理协商性等。网格还具有分布复杂,规模巨大;资源汇集,充分共享;动态增减,异构多样;同构类似,管理多重等普通特征。网格的多方参与性特征体现在源于各方,差异性强;数据海量、.功能不同;多方建设、协同维护;用户众多、需求各异。分析、研究这些特征对网格技术研究、应用以及网格建设有重要意义。  相似文献   

12.
Global consensus on the next generation of wireless mobile communications, broadly termed “beyond 3G”, sketches a heterogeneous infrastructure comprising different wireless systems in a complementary manner and vested with reconfiguration capabilities, which support a flexible and dynamic adaptation of the wireless network and its spectrum resources to meet the ever-changing service requirements. For ubiquitous reconfiguration to become a practical capability of mobile communication systems, it is necessary to establish a global architecture for modeling, expressing, and circulating essential metadata related to reconfiguration, including reconfigurable device capabilities and semantic properties of protocol stacks. We outline the relevant standardization initiatives in the mobile domain, summarize existing work in reconfiguration-supporting architectures, and identify key shortcomings that may hinder the advent of ubiquitously reconfigurable systems. Further on, we point out some major limitations of current metadata standards in the mobile domain for the representation of capability information pertaining to reconfigurable protocol stacks. Next, we identify essential metadata classes in support of reconfigurable communication systems, introducing an associated object-oriented UML model. We elaborate on the design rationale of the UML model, presenting and discussing the alternative metadata representation standards and suitable encoding formats. Finally, we demonstrate the suitability of our UML model by applying our reconfiguration-supporting vocabulary in the cases of a standardized protocol stack of 3G mobile devices and stationary 3G cellular network elements. Vangelis Gazis received his B.Sc. and M.Sc. (Communication Networking) degrees from the Department of Informatics & Telecommunications of the University of Athens, Greece, in 1995, and 1998, respectively. He also received an M.B.A. degree from the Athens University of Economics and Business in 2001. Since 1996 until, he has been with the research staff of the Communication Networks Laboratory (CNL) of the University of Athens. He has participated in national and European research projects (MOBIVAS, ANWIRE) of the IST framework programme. He specializes in reconfigurable mobile systems and networks for beyond 3G, metadata and ontology languages, reflective and component middleware, adaptable services and open API frameworks for telecommunications. He is currently a Ph.D. candidate in the Department of Informatics & Telecommunications of the University of Athens. Nancy Alonistioti holds a B.Sc. degree and a Ph.D. degree in informatics and telecommunications from the University of Athens. Presently, she is a senior researcher in the Department of Informatics and Telecommunications of the University of Athens. In the past, she has held a research position with the Institute of Informatics and Telecommunications of NCSR “Demokritos” in the areas of protocol and service design and testing, mobile systems (UMTS), open architectures, and software defined radio systems and networks. Her current research interests are in reconfigurable mobile systems and networks beyond 3G, and adaptable services, pervasive computing and context awareness. She has participated in several national and European R&D projects, and has been the technical manager of the IST-MOBIVAS and IST-ANWIRE projects, which have had a focus on reconfigurable mobile systems, networks an respective service provision. She is currently a member of the management team and workpackage leader in the FP6 IST-E2R project on reconfigurability; she also serves as technical manager for the University of Athens in the FP6 IST-LIAISON project, which focuses on location based services in working environments. Dr Alonistioti is co-editor and co-author of the book entitled “Software defined radio, Architectures, Systems and Functions”, published by John Wiley in May 2003. She has authored over 55 publications in the area of mobile communications and reconfigurable systems and networks. Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Athens, Greece, in 1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and 1984, respectively. From 1983 to 1986, he was on the faculty of the Electrical Engineering and Computer Science Department, University of Connecticut, Storrs. From 1986 to 1994, he was on the faculty of the Electrical and Computer Engineering Department, Northeastern University, Boston, MA. During the period 1993D1994, he served as Director of the Communications and Digital Processing Research Center, Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks Laboratory (UoA-CNL) and the Networks Operations and Management Center. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in the framework of the Advanced Communication Technologies and Services (ACTS) and Information Society Technologies (IST) programs funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE, E2R, LIAISON). His research interests are in the design and performance analysis of communication networks, and wireless/mobile communication systems and services. He has authored more than 190 papers in the above areas. Dr. Merakos is Chairman of the Board of the Greek Universities Network, the Greek Schools Network, and Member of the Board of the Greek Research Network. In 1994, he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications.  相似文献   

13.
龚强 《信息技术》2008,32(5):1-6
美国、欧洲、日本、泰国、韩国、马来西亚、中国,都启动了大型网格研究计划,并得到了产业界的大力支持.纵观世界各国网格技术的发展,呈现出以下几个特点:高度重视,投资巨大;百家争鸣,各有千秋;欧美争锋、普遍进步;突飞猛进注重应用.在未来的若干年里,网格的发展将在更加贴近应用,满足需求的前提下体现标准化整合、多技术渗透与融合、大型化以及广泛深入的应用发展趋势.  相似文献   

14.
Three alternative schemes for secure Virtual Private Network (VPN) deployment over the Universal Mobile Telecommunication System (UMTS) are proposed and analyzed. The proposed schemes enable a mobile node to voluntarily establish an IPsec-based secure channel to a private network. The alternative schemes differ in the location where the IPsec functionality is placed within the UMTS network architecture (mobile node, access network, and UMTS network border), depending on the employed security model, and whether data in transit are ever in clear-text, or available to be tapped by outsiders. The provided levels of privacy in the deployed VPN schemes, as well as the employed authentication models are examined. An analysis in terms of cost, complexity, and performance overhead that each method imposes to the underlying network architecture, as well as to the mobile devices is presented. The level of system reliability and scalability in granting security services is presented. The VPN management, usability, and trusted relations, as well as their behavior when a mobile user moves are analyzed. The use of special applications that require access to encapsulated data traffic is explored. Finally, an overall comparison of the proposed schemes from the security and operation point of view summarizes their relative performance. Christos Xenakis received his B.Sc. degree in computer science in 1993 and his M.Sc. degree in telecommunication and computer networks in 1996, both from the Department of Informatics and Telecommunications, University of Athens, Greece. In 2004 he received his Ph.D. from the University of Athens (Department of Informatics and Telecommunications). From 1998–2000 was with the Greek telecoms system development firm Teletel S.A., where was involved in the design and development of advanced telecommunications subsystems for ISDN, ATM, GSM, and GPRS. Since 1996 he has been a member of the Communication Networks Laboratory of the University of Athens. He has participated in numerous projects realized in the context of EU Programs (ACTS, ESPRIT, IST). His research interests are in the field of mobile/wireless networks, security and distributed network management. He is the author of over 15 papers in the above areas. Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Greece, in 1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and 1984, respectively. From 1983 to 1986, he was on the faculty of Electrical Engineering and Computer Science at the University of Connecticut, Storrs. From 1986 to 1994 he was on the faculty of the Electrical and Computer Engineering Department at Northeastern University, Boston, MA. During the period 1993–1994 he served as Director of the Communications and Digital Processing Research Center at Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks Laboratory (UoA-CNL) and the Networks Operations and Management Center. His research interests are in the design and performance analysis of broadband networks, and wireless/mobile communication systems and services. He has authored more than 150 papers in the above areas. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in the framework of the Advanced Communication Technologies & Services (ACTS) and Information Society Technologies (IST) programmes funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE). He is chairman of the board of the Greek Universities Network, the Greek Schools Network, and member of the board of the Greek Research Network. In 1994, he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications.  相似文献   

15.
The principal cause of speech recognition errors is a mismatch between trained acoustic/language models and input speech due to the limited amount of training data in comparison with the vast variation of speech. It is crucial to establish methods that are robust against voice variation due to individuality, the physical and psychological condition of the speaker, telephone sets, microphones, network characteristics, additive background noise, speaking styles, and other aspects. This paper overviews robust architecture and modeling techniques for speech recognition and understanding. The topics include acoustic and language modeling for spontaneous speech recognition, unsupervised adaptation of acoustic and language models, robust architecture for spoken dialogue systems, multi-modal speech recognition, and speech summarization. This paper also discusses the most important research problems to be solved in order to achieve ultimate robust speech recognition and understanding systems. Dr. Sadaoki Furui is currently a Professor at Tokyo Institute of Technology, Department of Computer Science. He is engaged in a wide range of research on speech analysis, speech recognition, speaker recognition, speech synthesis, and multimodal human-computer interaction and has authored or coauthored over 450 published articles. From 1978 to 1979, he served on the staff of the Acoustics Research Department of Bell Laboratories, Murray Hill, New Jersey, as a visiting researcher working on speaker verification. He is a Fellow of the IEEE, the Acoustical Society of America and the Institute of Electronics, Information and Communication Engineers of Japan (IEICE). He was President of the Acoustical Society of Japan (ASJ) from 2001 to 2003 and the Permanent Council for International Conferences on Spoken Language Processing (PC-ICSLP) from 2000 to 2004. He is currently President of the International Speech Communication Association (ISCA). He was a Board of Governor of the IEEE Signal Processing Society from 2001 to 2003. He has served on the IEEE Technical Committees on Speech and MMSP and on numerous IEEE conference organizing committees. He has served as Editor-in-Chief of both Journal of Speech Communication and the Transaction of the IEICE. He is an Editorial Board member of Speech Communication, the Journal of Computer Speech and Language, and the Journal of Digital Signal Processing. He has received the Yonezawa Prize and the Paper Awards from the IEICE (1975, 88, 93, 2003), and the Sato Paper Award from the ASJ (1985, 87). He has received the Senior Award from the IEEE ASSP Society (1989) and the Achievement Award from the Minister of Science and Technology, Japan (1989). He has received the Technical Achievement Award and the Book Award from the IEICE (2003, 1990). He has also received the Mira Paul Memorial Award from the AFECT, India (2001). In 1993 he served as an IEEE SPS Distinguished Lecturer. He is the author of “Digital Speech Processing, Synthesis, and Recognition” (Marcel Dekker, 1989, revised, 2000) in English, “Digital Speech Processing” (Tokai University Press, 1985) in Japanese, “Acoustics and Speech Processing” (Kindai-Kagaku-Sha, 1992) in Japanese, and “Speech Information Processing” (Morikita, 1998) in Japanese. He edited “Advances in Speech Signal Processing” (Marcel Dekker, 1992) jointly with Dr. M.M. Sondhi. He has translated into Japanese “Fundamentals of Speech Recognition,” authored by Drs. L.R. Rabiner and B.-H. Juang (NTT Advanced Technology, 1995) and “Vector Quantization and Signal Compression,” authored by Drs. A. Gersho and R. M. Gray (Corona-sha, 1998).  相似文献   

16.
介绍了澳大利亚插头产品的法规要求及插头的型式、尺寸、参数和测试要点,分析了插头的电流额定值和配线之间的关系,强调了插销绝缘套的要求.对重要的试验项目,如弯曲试验、插销绝缘套的耐磨试验、温升试验、高温压力试验进行了说明.  相似文献   

17.
The tremendous momentum toward building a mobile wireless Internet using the Internet Protocol (IP) has thrust many challenges upon the technology developers and the operators. These challenges encompass the 2.5G, 3G, and future solutions and standards. Some of the key issues deal with supporting IP traffic across different wireless and MAC protocols, end-to-end QoS and mobility, traffic engineering and scalability, protection/restoration, operations and management, authentication/privacy/security, billing, and content and context aware networking. This article addresses the drivers, the issues, and solutions (wherever possible) in the above areas, and concludes with a summarization of the challenges that lie ahead.  相似文献   

18.
PKI是目前在电子商务中安全传输方案,SSL和SET两种安全的电子交易协议,在网上交易中有着广泛地应用,是大多数在线支付所采用的支付协议。这里在探讨PKI、SSL、SET技术原理的基础上,对它们各自的作用、技术实现、工作漉程等进行了描述;对它们之间的联系、区别、应用范围进行了深入的分析。  相似文献   

19.
组呼通信在指挥调度中有着重要作用,而在一些地面没有基站的地方,就无法正常使用。卫星通信具有无视地形,通信范围广,不易受陆地灾害影响,易于建设等优点。把卫星通信和组呼通信结合在一起的卫星组呼通信技术兼顾两者的优点,能更好的发挥指挥调度这一作用。当前卫星组呼通信采用固定频率方式,组呼成员在一个频率下进行通信,这种方式实用性不好。本文研究的是移动卫星组呼,在GMR-1系统的基础上研究了卫星组呼通信中MAC层的功能,提出了MAC-Ready-Gcc、MAC-Dedicated-Gcc这两个为了支持组呼的状态,并针对在MAC层发生的PTT竞争提出了一种回退策略。  相似文献   

20.
在数字化中国的大背景下,在公司个人宽带与互动电视在线交费用户均突破300万户的情况下,为解决我们的用户总找不到自己喜欢看的节目,记不住频道名称和喜欢的节目,提升公司竞争力。通过对前端的点播系统、AAA系统、EPG系统、PORTAL系统、ISMP系统、媒资系统、机顶盒终端的功能进行剥离、整合和详细设计,最后完成终端用户语音操控电视直播、点播、时移、回看、页面操控、系统设置,并支持普通话和四川话方言的目的。达到提升用户体验,增加公司竞争力,促进业务的发展。系统试运行后,用户体验效果得到很大提升,完全达到预期设计目的。  相似文献   

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