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J. E. Russell 《International Journal of Wireless Information Networks》1994,1(3):149-163
It is postulated that today we are in the midst of a major paradigm shift in the communications industry. The essence of this paradigm shift is a transition from today's universal telephone service which has been perfected over the past 100 years, to a future communication service environment, referred to as universal personal communication. Under this new paradigm, communications will be person based in contrast to the predominantly location-based communication environment of today. Societal trends, evolving global standards for communication, regulatory policies, and emergent technologies are seen as the forces driving such a transition. Universal personal communications will be characterized by flexible access to universal services permittingmore enduser control which will result in personalization and customization of such services. Furthermore, the centralized intelligence focus of today's communication networks needs to evolve toward a focus where network intelligence can be migrated to the periphery of the core transport network. The viability of universal personal communication will be critically dependent upon how well it addresses the end customer value proposition. Two key elements of this proposition are transparency of mobility and personalization of service environments. A zonal service environment model which classifies and characterizes these various service environments in terms of common communication parameters is proposed. This model is built around hierarchical structures for both cellular and digital wireless transmission, and can be viewed as critical towards the realization of transparent mobility management and personalization of services. 相似文献
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Jahn A. Holzbock M. Muller J. Kebel R. de Sanctis M. Rogoyski A. Trachtman E. Franzrahe O. Werner M. Fun Hu 《Communications Magazine, IEEE》2003,41(7):36-43
The demand to make air travel more pleasant, secure, and productive for passengers is one of the winning factors for both airlines and the aircraft manufacturing industry for which aeronautical communications is one of the enablers. This article describes current trends in the area of aeronautical passenger communication toward personal and wireless in-cabin communications and multimedia data networks. Technological challenges are summarized as well as market potentials and regulatory issues. 相似文献
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移动通信业在经过十年的繁荣之后,不得不冷静地思考今后如何生存和发展的问题。 如果说业界过去关注的焦点是新一代技术研发与推广,以便争夺国际市场,那么今天更多的是关注如何挖掘现有基础设施的潜力来提高收益和积累资金以求生存与发展。投资者则对大规模建设项目持更为谨慎的态度,决不介入无把握的风险投资。 原来运营商们都认为互联网业务真的每一季度会翻一番,移动通信会长驱直入。结果他们都在残酷的事实面前大失所望。但是,外国厂商对亚洲市场,特别是加入WTO之后的中国市场的兴趣并未减少。他们认为在这些地区开放市… 相似文献
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Eli Skogerbø 《Telematics and Informatics》1997,14(4):383-393
The article takes a starting point in theories on the distinctiveness of “small states” and discusses the relevance of this approach in the analysis of the current changes in communication policies in Europe. In order to assess the applicability of these perspectives, external constraints on national policy-making are identified. These constraints, convergence of technologies and markets and the Europeanisation of communications polices work as levelling forces on differences across countries, and should, accordingly, contribute to the removal of national characteristics. In the second part of the article this hypothesis is challenged although not refuted. Drawing on instiutional perspectives on political and social change and data from an on-going research comparative policy analysis-project, the author argues that historical legacies and national characteristics may have a lasting and distinctive effects on the formulation of communication policies also in the future. 相似文献
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通信行业安全生产管理是各运营商生产经营工作稳定运转的重要保障,安全生产信息化管理平台的构建是企业管理的重要环节。文章介绍了通信行业安全生产信息化管理平台主要功能和整体架构,描述了安全生产管理平台的主要模块及其功能。 相似文献
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《网络电信》2008,(3):I0011-I0018
“In 1976, the United States launched the first practical optical fiber communications systems in the world, and unveiling the prelude of the development history of optical communications. Hence the development of China's optical fiber and cable industry is keeping up development with the world, China started to build the first experimental optical fiber communications line in 1978 and China set up two optical fiber and cable joint venture in the late 1980s. In the 1990s, China's rapid economic development has directly spurred the development of the telecommunications industry, the business on optical communications came out for a short period of time. In 2001 in the peak period of the optical fiber and cable market, the total number of the enterprises surpasses 200. With the decline of the world's communications market, China's optical communications market also has drastic shrinks. Since the decline from 2002, the demand of China started to rising up. At the same time, China's optical communications market in 2007 also began to enjoy its recovery.” 相似文献
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本文对通信行业节能减排的思想进行了分析,并对通信行业节能减排的措施和管理进行了论述,说明了通过实施节能减排措施,完善管理体系,可以有效地推进节能减排工作. 相似文献
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国外军用飞机平视显示器的发展 总被引:8,自引:0,他引:8
平视显示器是现代化军用飞机中的主飞行显示器.了解国外平视显示器的发展趋势可以为国内平显的发展方向提供参考.在分析研究大量资料的基础上,指出目前军用平显的发展趋势.给出了合成视景平视显示器的概念、优点、工作原理、显示格式,及国外平板类平视显示器的研究现状. 相似文献
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《Vehicular Technology, IEEE Transactions on》1976,25(4):191-192
This standard defines the minimum requirements for a multiplex or nonmultiplex voice/telemetry channel to assure compatibility and interoperability of portable physiologic monitoring equipment with both radio and telephone equipments and hospital emergency and display devices. Specifically, it defines a National telemetry subcarrier frequency within the voice band which is compatible with both radio and telephone transmission characteristics. This standard applies only to voice and telemetry modulation-demodulation electronic instrumentation used in emergency medical care. 相似文献
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G. Russell Pipe 《Telematics and Informatics》1984,1(4):409-418
The terminological and conceptual background in which national and international information policy have developed are described. Transborder data flow, a term which increasingly is used to represent the international aspects of information policy, comprises both technical and non-technical features of content and carriage issues. Legislation applying to personal information, concerns over data security and vulnerability of information systems and economic policy aspects are reviewed. 相似文献
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Evolution of satellite communications: Integration of ETSI BSM and DVB‐RCS for future satellite terminals
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Tomaso de Cola Mario Marchese Maurizio Mongelli 《International Journal of Satellite Communications and Networking》2016,34(2):131-154
The main added value of the European Telecommunications Standards Institute broadband satellite multimedia (ETSI BSM) architecture is the definition of the Satellite Independent‐Service Access Point (SI‐SAP) protocol interface, which formally separates Satellite Dependent (SD) from SI layers, thus enabling the implementation of powerful vertical QoS mapping strategies. On the other hand, DVB‐S2/RCS satellite standard is considered the driving technology to integrate satellite with terrestrial infrastructure and provide up‐to‐date services. This paper focuses on the integration of ETSI BSM architecture and DVB‐RCS technology, by analysing the adaptations needed on real DVB‐RCS terminals to be interoperable with the SI‐SAP interface. To this end, the detailed design of an underlying architecture taking into account required adaptations and new functionalities is proposed. The possible further evolutions of the BSM specification are also highlighted, showing the potential for the development of future devices integrating both DVB‐RCS and ETSI BSM architectures also in view of the recent upgrade to the DVB‐RCS2 standard. The paper also validates the SI‐SAP QoS functionalities and proves the performance benefits in terms of QoS and quality of experience of Web‐browsing by means of a satellite emulator developed fors this aim. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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随着新一代信息技术与先进制造技术的深度融合,智能制造成为新时代高端装备制造企业转型升级的重要途径。通过分析在数字经济浪潮下,高端装备行业的趋势和企业发展过程中面临的机遇与挑战,提出了通过智能制造实现制造业的转型发展道路的思考,并就企业如何推进智能制造规划和建设提出了具体的建议。 相似文献
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根据BA无标度网络模型提出了一种具有无标度特性的有向网络演化模型,并设计程序进行了仿真实验,对有向网络的度分布进行了分析,结果表明,利用文中提出的有向网络演化模型生成的复杂有向网络的度分布符合幂律分布,能有效的模拟现实世界的具有无标度特性的复杂有向网络,可以在此模型上展开对复杂有向网络的其他相关拓扑性质的分析及研究。 相似文献
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