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1.
2005年10月11日《中共中央关于制定国民经济和社会发展第十一个五年规划的建议》中指出“加强宽带通信网、数字电视网和下一代互联网等信息基础设施建设,推进‘三网融合’,健全信息安全保障体  相似文献   

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A forecast of the practical and promising devices, circuits, and systems that can be expected in the next one to five years is presented. It is based on a survey of a group of distinguished practitioners throughout the industry. The forecasts cover the areas of lasers and electrooptics, integrated optoelectronics, electron devices, digital integrated circuits, high-frequency and microwave devices, VLSI signal and image processing systems, analog ICs and signal processing, power electronics and systems, neural systems and applications, and medical image and signal processing. A particularly optimistic outlook is seen for lasers, fiber optics, optoelectronic ICs, and optical switching and processing. Digital ICs and power electronics are also expected to make steady gains. In addition, flat panel displays will attract a fair amount of activity, with the liquid-crystal and electroluminescent types emerging as the leaders in this decade. Looking further out, advances in artificial and biological neural systems represents a natural extension to more sophisticated problem-solving in speech processing, vision and communications  相似文献   

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The authors describe some of the current neural prostheses and examine technological developments needed for future generations of neural prosthetic implants. Current developments include the peroneal nerve stimulator, upper and lower extremity functional neuromuscular stimulation and the auditory prosthesis. Three issues connected with future developments include stimulating and recording electrodes, the interconnection system, encapsulation, the command unit, force, touch, and position sensors, and signal conditioning  相似文献   

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The Montreal Protocol controls the manufacture and use of substances that deplete the Earth's stratospheric ozone. Amongst the chemicals under regulatory control are two halogenated solvents used widely in the electronics industry: CFC-113 and 1.1.1 trichloroethane. The paper gives the environmental science of ozone depletion and its ecological impact. The properties and uses of the common halogenated solvents are discussed and the range of more environmentally acceptable cleaning options, suitable for the applications in the electronics industry, are given  相似文献   

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Lidgate  D. 《IEE Review》1990,36(1):27-30
All conventional energy sources are now under attack from conservationists, and the changing ESI privatisation plans have cast a cloud over Britain's nuclear future. The author discusses the state of fossil fuel power production in the UK and then discusses the alternatives including renewable energy sources. The possibilities of using wind energy and a Severn barrage are discussed. The effects on the environment of renewables is also discussed  相似文献   

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《IEE Review》1990,36(4):131-134
The availability of cheap optical fibre and associated transceivers has encouraged the development of the next generation of computer networks. Most prominent among these is the fibre distributed-date interface (FDDI), which is expected to become a standard. The authors describe the principal advantages of the FDDI (namely its size and transmission rate) and outline the apparently bright future of FDDI networks and their applications  相似文献   

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Wright  D.J. To  M. 《IEEE network》1990,4(2):34-40
The extent of the diversity in telecommunication services of the next decade is investigated, using a number of transport-oriented characteristics. Groups of services that have similar transport requirements are identified. The results are shown to have implications on priority considerations in the headers of asynchronous time-division multiplexing (ATDM), otherwise known as asynchronous transfer mode, cells, and also to provide an introduction strategy for ATDM switching into the present network. A detailed service characterization and a taxonomy of services are included  相似文献   

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In addition to inducing attenuation and depolarization in satellite links, scattering by rain can create intersystem interference. This type of interference was investigated extensively in the 1970s for terrestrial paths, but little has been done to study its effects on modern and future satellite links. Studies of the potential interference created by the scattering of an uplink signal into an adjacent satellite and the inverse case where a downlink signal is scattered into the earth station of an adjacent satellite system are reported. Two computation methods for the interfering power are presented. The first, based on the bistatic radar equation, takes only the first-order multiple scattering into account, whereas the second method, based on the radiative transfer equation, includes higher orders of multiple scattering  相似文献   

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The growth of a conversational audio-visual service such as videoconferencing depends on an ability to provide a complete system at a price the customer can afford. Video compression technology can play a significant role by drastically reducing transmission costs. The paper outlines progress in establishing a new standard, H.261, for video coding bit rates between 64 kbit/s and 2 Mbit/s  相似文献   

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People, not technology, have become the focus of current interface design. Multimedia interface designers try to take advantage of human senses to ease our communication with one another and with the computer. This survey of current work highlights the complexity facing them in their task  相似文献   

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本文概述九十年代通信技术的新动向,主要讲卫星通信、移动通信、光纤通信以及公用和专用通信网传输技术的发展趋势。文中着重指出各种有前途的新技术,包括卫星通信的星上点波束天线,小孔径天线地面终端,与ISDN兼容;数字移动通信的蜂窝微区(micro-cell),个人便携通信的无线接入交换网;光纤通信的掺铒光纤放大器,DFB调谐单频激光管,多量子阱(MQW),光电子集成,外差检测,密集FDM多路载波通信;以及公用通信网数字化、综合化、宽带化组成B-ISDN,同步光纤网,同步数字体系,异步转移方式;专用通信网的局域网(LAN和MAN),光纤分布数据接口,分隙环(slotted ring),分布排队双总线等新建议。  相似文献   

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Since the mid-1980s, the Chinese audiovisual industry has gone through a series of institutional reforms aimed at decentralization and marketization. The reform measures from the mid-1980s to the mid-1990s affected the general trend in film production and criticism during the period. The outcome of film reform has been the commercialization and privatization of the Chinese film industry and the surge of entertainment pictures. Meanwhile, the global popularity of Hollywood pictures (re)defined what counted as quality films for Chinese audiences. As such, the industrial structure and market practice institutionalized by Hollywood have become the new model for the Chinese film industry. Approached from an institutional perspective, this article gives major attention to the structural formation of the market and the audiovisual industries, that is, the industries' ownership and control related to state policy.  相似文献   

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There can be few topics developing faster than automotive electronics. Although the application of microcomputer-based systems is now well established for the control of automobile engines, there is still greater scope for the use of high-reliability electronic technology in other areas of vehicle operation. Amongst these are systems, such as air-bags, which improve safety, and also features which improve comfort and convenience. In this paper the operation of electronically controlled antilock braking systems (ABS) and electrically power-assisted steering (EPAS) is examined  相似文献   

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在20世纪90年代,美国的CATV一直领先于信息技术(IT)产业。不断发展并取得了巨大的进步。回顾美国这11年(1989~1999)的发展历程,供国内业界人士借鉴,将有利于国内CATV事业在新世纪中的发展。现参照美国有线电视协会(NCTA)的’2000年会有关资料,对其11年来的发展作一综述以供读者参考。  相似文献   

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In this paper the recent considerations of NASA's Earth Observing System Science and Mission Requirements Working Group are summarized. The Working Group was chartered to consider the broad Earth Science objectives that could be addressed from a low-earth orbital perspective in the 1990s, together with consideration of the specific observations and instrument packages that would be needed to meet the science objectives. The concept that was developed diverges somewhat from past practices in that the Working Group chose to consider Eos as an information system, where mission operations, Eos databases, and information about other relevant data sets are tied together by an information network. The network would link users with mission data repositories, with Eos and non-Eos data archives, and with subsets of Eos and related data maintained as active research databases. Three Eos instrument packages were chosen on the basis of synergistic groupings of instruments to make simultaneous observations of selected phenomena over a variety of wavelengths. The suggested packages are: 1) a surface-imaging and-sounding package, with two imaging spectrometers, a high-resolution multifrequency microwave radiometer, and a Lidar atmospheric sounder and altimeter; 2) an active microwave package, with a synthetic-aperture radar, an altimeter, and a scatterometer; and 3) an atmospheric physical and chemical monitoring package, with a variety of instruments to measure atmospheric chemistry, winds, and energy balances. The significant observing capabilities offered by the Eos instrument packages, if implemented in the proposed information system environment, will allow significant increases in our understanding of global processes operating above, on, and beneath the earth's surface.  相似文献   

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Modern reflector theory and practice, with emphasis on the recent past are reviewed. Included are a brief historical review and performance definitions for the nonspecialist. Special sections are devoted to shaped multiple reflectors, reflector surface metrology, and reflectors for the next decade and beyond. In spite of decreasing budgets for scientific, commercial, and military space programs, the 1990s promise to be a true golden age for the reflector antenna art  相似文献   

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1 理顺体制是有线电视事业建设的前提1.1 理顺隶属关系 ,加强企业领导由于企业党委领导重视和认识程度不同 ,石油企业有线电视在发展过程中曾经走过一段弯路 ,如有的隶属通信部门 ,有的隶属工会组织 ,因此挫伤了部分电视工作者办台的积极性 ,影响了有线电视事业的发展。后来企业党委总结经验教训 ,根据有关文件精神 ,明确规定企业电视台隶属于企业党委直接领导 ,它的具体任务是 :(1)根据企业党政组织的总任务 ,制定具体宣传规划 ,努力做好阶段性的配合宣传。(2 )为保证企业生产经营的顺利实施 ,应开展丰富多彩的报道 ,传递信息 ,发挥引导…  相似文献   

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