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新一代移动通信系统包括目前的3G移动通信系统、下一代B3G/4G移动通信系统,以及无线宽带通信系统。论述了新一代移动通信测试技术在系统和终端设备研制生产中的需求,给出了3G通信系统测试、3GPP数据增强系统测试、CDMA2000-1X高速数据传输测试、3GPP LTE通信系统测试、WiMAX通信系统测试、B3G/4G通信系统测试和UWB无线通信测试技术的方向与重点。 相似文献
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CIE-computer-integrated enterprise-technically best describes the Hibernia's new Grand Banks, Newfoundland, offshore drilling and production platform. Designed and constructed in an era of oil company belt-tightening, Hibernia takes advantage of modern technology to achieve the goal of a safe, cost-effective control system design. Some of the design criteria used in the control system design are discussed: system operability, training, safety, maintainability, constructability, expandability and integration, engineering/management information, and cost effectiveness. The main features of the control system are then described including: the process control system, fire and gas detection system, emergency control system, ECS/PCS process shutdown, electrical power management system, HVAC control system, drilling data acquisition system, and the engineering/management information system 相似文献
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软交换平台是下一代网络的核心功能实体之一,为下一代网络提供具有实时性要求的业务呼叫控制和连接控制功能。文章介绍了下一代网络的基本概念,重点论述了软交换平台的体系结构、以软交换技术为基础的下一代交换网络的电力发展策略,以及在下一代电力通信网络中的重要应用,强调了下一代网络将成为未来几年电力通信发展和建设的重要方向。 相似文献
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Hasegawa T. Yamaji K. Irokawa H. Shirahama H. Tanaka C. Akabane K. 《Power Delivery, IEEE Transactions on》1996,11(4):1783-1788
A high voltage thyristor valve is the basic component of an HVDC transmission system. Development of a 500 kV valve for next generation HVDC transmission systems is described. First, the power loss of the valve is analyzed to decide a reasonable wafer size for the light-triggered thyristor. From these results, a six inch diameter wafer size is selected. A light-triggered thyristor, with ratings of 8 kV and 3.5 kA, is developed using the six inch wafer. The design of the valve employing the thyristor and test results with a prototype valve prove that a 500 kV valve can be realized by this design method 相似文献
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《Engineering & Technology》2008,3(11):60-63
The more we come to rely on search engines, the more we find their shortcomings. With public searchers like Google lurching toward more commercial business models, should organizations consider building their own search engines? By Chris Edwards. "Everyone thinks search is typing keywords into a box," says Mike Lynch, the head of search specialist Autonomy. "But that is going to change." The science of Web searching has reached a crucial stage in its development: for proof just Google 'Web search future'. Lynch reckons that, as the mechanics of search head into the deepest recesses of the IT system, it will steadily reduce our dependence on Google as a primary Web inquisitor, and make that box fade from our memories. 相似文献
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Demands for network bandwidth increase daily. In order to meet our ever-increasing network bandwidth needs, one solution is to design and build the next generation Internet with an optical core infrastructure, with last connection provisioning time and unprecedented high data rates of 100 terabits per second and higher. An optical network is built by interconnecting various optical switches with wavelength-division multiplexing (WDM) fibers, i.e., fibers that can simultaneously transmit data over different wavelengths. Many of today's commercial optical networks, however, do not utilize the WDM technology efficiently. With respect to the current state of the technology, an Optical Burst Switched (OBS) Network is one of the most promising all-optical architectures for the next generation Internet. It efficiently supports the transmission of bursty traffic over an all-optical infrastructure. OBS is still being developed and it has not been standardized yet. This article describes the main features of an OBS network, its benefits as well as its challenges. 相似文献
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Since the present hierarchical power grid structure and AC interface are mature and rigid, a new electric power system architecture is proposed here to save the earth by making use of renewable energy sources. The architecture consists of a new concept and a historical technology, that is, a network of many “electric clusters” with a DC interface. The cluster includes dispersed electric power generators, electric appliances, electric storage, and “electric power routers.” The router is equipment to resourcefully route electrical energy between neighboring clusters and to manage electrical energy in the cluster. The transfers of electrical energy (between clusters and within clusters) and the generation of electricity from renewal energy sources (such as sunlight, wind, tides, and biogas) are intermittent and have very wide dynamic ranges, so that the interface must make use of DC. When we achieve an energy society with this architecture, we will be able to reduce energy consumption, greenhouse gas emissions, and materials use. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(1): 18–25, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20039 相似文献
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《Engineering & Technology》2009,4(8):40-42
The emergence of highspeed 3D image processing technologies is a major milestone for the vision industry as it represents the most significant step change in processing capabilities since the development of the 2D pattern recognition algorithms. 相似文献
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当前网络应用层存在许多安全问题并缺少有效的安全认证机制,文中介绍了IPng的特色、以IPSec为基础的安全概念与功能,以及在IPv6新体系下在其应用领域中采用的安全策略。 相似文献
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速率匹配单元是WCDMA系统相对于其他2G到3G的移动通信系统比较独特的基带信号处理单元。论文从算法、思想、执行流程上分析了速率匹配的目的、原理与意义,并简略介绍了一种硬件设计实现的方案。 相似文献
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