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1.
Domination of the electromagnetic spectrum is a crucial component of the 21st century warfare. In the harsh electromagnetic environment of the modern battlefield, it is of the utmost importance to deny the opposing force the opportunity to attack or exploit the detection/interception of friendly communications assets through the deployment of electronic protection (EP) measures in order to attain low probability of detection (LPD), low probability of interception (LPI) and anti-jam (A/J). Given that directional antennas are a suitable means to achieve both extended range and LPD/LPI, this paper proposes mechanisms to optimize the trade-off between these capabilities, minimizing the number of hops and end-to-end delay when routing packets in a multi-hop ad-hoc network, while taking into account stealth requirements. The novel scheme is based on a variant of Fisheye State Routing, coupled with a power control algorithm to guarantee a LPD/LPI beyond the zone covered by the omni-directional radiation footprint of the network. The performance of the proposed scheme is evaluated through computer simulation. 相似文献
2.
A laboratory information management system (LIMS) can make a major contribution to the quality and therefore to the efficiency
and competitiveness of a laboratory. Since it can impact all aspects of a laboratory's organization it must be the key if
not the principal player of the laboratory's quality system. It should support the laboratory in establishing, maintaining
and applying quality procedures thereby enabling the laboratory to achieve its quality goals. As a tool, LIMS permits the
laboratory to input and use its own know-how and experience to optimize the total organization (internal and external) and
workflow of generated information. However, perceived "quality" in the context of an LIMS, can be viewed as being made up
of different facets such as the security, reliability and accessibility of information as well as its turn around time and
production cost. This paper reviews the role of a LIMS in the laboratory and the contribution that both system design and
functionality can have on "building quality ".
Received: 5 October 1998 · Accepted: 20 October 1998 相似文献
3.
With the recent growth in smartphone services, the “mobile” environment has become a key factor to consider in the design of the future Internet. In this paper, we propose Mobile‐Oriented Future Internet (MOFI), which is a new architecture for the future Internet for mobile‐oriented environments. The MOFI architecture is designed with three functional features: global identifier and local locator in the identifier‐locator separation, query‐first data delivery for route optimization, and distributed control of identifier‐locator mapping. The proposed architecture and functional operations are implemented and tested using the Linux platform. From the experiment results, we see that the MOFI architecture performs better than the existing identifier‐locator separation schemes, such as Proxy Mobile IP and Host Identity Protocol, in terms of data throughout, mapping control overhead, and handover delay. 相似文献
4.
FEPPCON研讨会与电力电子的未来展望 总被引:1,自引:0,他引:1
2004年5月在意大利举行的第五届FEPPCON国际研讨会上,近40位欧美电力电子专家、学者和工程师讨论了电力电子及其应用的中长期发展前景,包括以下主要问题:电力电子和系统、系统集成,储能技术、分布式电力系统和电动(或混合电动)汽车中电力电子的应用、计算机及其它用途的标准电源模块、电力电子装置性能的改进(智能控制、能量管理、热问题、无源元件集成等)。本文摘要介绍FEPPCON国际研讨会并评述FEPPCON-5的讨论和总结。 相似文献
5.
宽带光纤接入网及其发展展望 总被引:2,自引:0,他引:2
文章指出各种宽带光纤接入网都有其最佳使用场合和时机,宽带点到点有源光纤系统最适合企事业用户;宽带点到点有源以太网光纤系统适合在低密度用户分散地区应用;宽带点到多点无源光纤系统最适合新建或改建的密集用户区应用.文章认为中国宽带光纤接入网的发展将可能跨越ATM无源光网络(APON)、宽带无源光网络(BPON)和以太网无源光网络(EPON)阶段,从宽带点到点以太网光纤系统和千兆比特以太网无源光网络(GEPON)开始,较快地过渡到千兆比特无源光网络(GPON). 相似文献
6.
中国互联网发展的带宽不足、上网速度慢,是长期制约我国电信网络发展的瓶颈.随着"2001宽带年"宽带网建设的启动,将为我们早日铺就信息高速公路. 相似文献
7.
8.
曾一江 《中国电子科学研究院学报》2011,6(4):391-395
S模式ADS-B系统概念结合了自动相关监视和S模式信标雷达,是一种监视和数据链的综合系统,包括机载设备和地面设备,它是在S模式二次监视雷达的基础上发展起来的一种新型的空管监视系统,正逐步得到国际上的广泛应用。介绍了S模式ADS-B的原理及应用范围,并对其性能进行了详细的对比分析。 相似文献
9.
Some experimental results of LC in capillary columns are presented. The possible effect of turbulence which has been much emphasised lately is overrated. The future of LC in capillary columns lies in extreme miniaturization. 相似文献
10.
Recent advances in disruptive technologies, such as P2P content distribution, and research in high-speed optical and wireless transmission and in the virtualization of systems have sparked fundamental discussions about how to design the future Internet: Is a clean-slate approach mandatory? Would an evolutionary process be more appropriate? What kind of network and application features will drive the design of the future Internet? The aims of this position paper are to outline the technological trends and challenges for the emerging future Internet and to discuss the requirements and implications. 相似文献