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91.
本文作者对廊坊市信息化建设存在的问题进行了分析,并提出了推进我市信息化建设的建议。  相似文献   
92.
厂商之窗     
《现代电视技术》2008,(2):153-158
辽宁电视台、索尼中国专业系统集团签署战略合作伙伴备忘录,广电总局数字节目管理中心采用大批Sony高端设备,北京电视台批量采购Sony HDCAM设备,汤姆逊测试技术再次荣获艾美技术大奖[编者按]  相似文献   
93.
Summary The analytical roles of chromatographic variables (column length, etc.) can be soundly comprehended and compared in terms of the precision (Φ) of measurements and efficiency (ϑ) of analysis which are described as Shannon information and information flow, respectively. The φϑ plots of the optimization process and the information Φ transmitted by a single peak are useful to understand the analytical structure of optimization. Variables treated here are mobile phase composition (X), column length (L), mobile phase velocity rate (u), detection wavelength (λ) and plate number (N).  相似文献   
94.
宽带IP城域网及其应用   总被引:1,自引:0,他引:1  
文章结合南京电信公众宽带IP城域网的建设,对宽带IP城域网的网络结构、用户接入安全、网络管理和认证计费作了阐述,并简要介绍了应用于宽带IP城域网上的一些业务。  相似文献   
95.
国内物流形势及邮政物流分析   总被引:3,自引:0,他引:3  
介绍了国内物流业的发展现状以及中国邮政的优势,提出了对中国邮政发展物流的个人看法。  相似文献   
96.
以勘察设计的经历,从技术先进、适用、可持续发展和升级、安全可靠、可建设和可维性出发,对当前信息与通信网的急剧发展、渗透和综合后出现的信息新技术和闪烁的通信新亮点进行了一些探讨性分析。  相似文献   
97.
本文通过简要介绍胜利股份信息管理系统的建设及实施情况,探讨如何建立一套先进的适合于本企业发展的管理信息系统.  相似文献   
98.
We report on ideas, problems and results, which occupied us during the past decade and which seem to extend the frontiers of information theory in several directions. The main contributions concern information transfer by channels. There are also new questions and some answers in new models of source coding. While many of our investigations are in an explorative state, there are also hard cores of mathematical theories. In particular we present a unified theory of information transfer, which naturally incorporates Shannon's theory of information transmission and the theory of identification in the presence of noise as extremal cases. It provides several novel coding theorems. On the source coding side we introduce data compression for identification. Finally we are led beyond information theory to new concepts of solutions for probabilistic algorithms.

The original paper [R. Ahlswede, General theory of information transfer, Preprint 97-118, SFB 343 Diskrete Strukturen in der Mathematik, Universität Bielefeld, 1997] gave to and received from the ZIF-project essential stimulations which resulted in contributions added as GTIT-Supplements “Search and channels with feedback” and “Noiseless coding for multiple purposes: a combinatorial model”.

Other contributions—also to areas initiated—are published in the recent book [R. Ahlswede et al. (Eds.), General Theory of Information Transfer and Combinatorics, Lecture Notes in Computer Science, vol. 4123, Springer, Berlin, 2006].

The readers are advised to study always the pioneering papers in a field—in this case the papers [R. Ahlswede, G. Dueck, Identification via channels, IEEE Trans. Inform. Theory 35 (1989) 15–29; R. Ahlswede, G. Dueck, Identification in the presence of feedback—a discovery of new capacity formulas, IEEE Trans. Inform. Theory 35 (1989) 30–39] on identification. It is not only the most rewarding way to come to new ideas, but it also helps to more quickly grasp the more advanced formalisms without going through too many technicalities. Perhaps also the recent Shannon Lecture [R. Ahlswede, Towards a General Theory of Information Transfer, Shannon Lecture at ISIT in Seattle 13th July 2006, IEEE Information Theory Society Newsletter, 2007], aiming at an even wider scope, gives further impetus.  相似文献   

99.
Wireless mobile networks from the fifth generation (5G) and beyond serve as platforms for flexible support of heterogeneous traffic types with diverse performance requirements. In particular, the broadband services aim for the traditional rate optimization, while the time-sensitive services aim for the optimization of latency and reliability, and some novel metrics such as Age of Information (AoI). In such settings, the key question is the one of spectrum slicing: how these services share the same chunk of available spectrum while meeting the heterogeneous requirements. In this work we investigated the two canonical frameworks for spectrum sharing, Orthogonal Multiple Access (OMA) and Non-Orthogonal Multiple Access (NOMA), in a simple, but insightful setup with a single time-slotted shared frequency channel, involving one broadband user, aiming to maximize throughput and using packet-level coding to protect its transmissions from noise and interference, and several intermittent users, aiming to either to improve their latency-reliability performance or to minimize their AoI. We analytically assessed the performances of Time Division Multiple Access (TDMA) and ALOHA-based schemes in both OMA and NOMA frameworks by deriving their Pareto regions and the corresponding optimal values of their parameters. Our results show that NOMA can outperform traditional OMA in latency-reliability oriented systems in most conditions, but OMA performs slightly better in age-oriented systems.  相似文献   
100.
通过设计和使用成本管理信息系统,实现从手工统计到系统计算的转变.详细阐述了该系统的设计目标、设计原则、设计思路和实现办法.阐述了运行效果,并提出今后的努力方向.  相似文献   
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