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141.
本文归纳分析出亚太光纤市场的两个显著特点,介绍了亚太地区光通信发展水平,以及亚太各国和地区间的光通信合作,指出亚太光纤市场得以迅速发展的主要原因。 相似文献
142.
全新的智能型电话机,结合了先进的电脑技术和传统的电话技术,功能日趋多元化。本文介绍了国内智能电话机的技术水平、产品现状及生产厂家,并对其未来发展提出了观点。 相似文献
143.
In this approach, the complexity of the self-organizing microstructure of the stock exchange is explicitly taken into consideration: the process of offers and trades as well as the adjustment of individual expectations are modelled with help of a (stochastic) jump process. Its abilities are illustrated by modelling the continuous quotations of asset prices at an auction type stock exchange. The functional form of the transition (hazard) rates is chosen to reflect the individual preferences and expectations as well as the economic environment. The model is described in detail and examples of Monte Carlo simulation results are presented. 相似文献
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145.
为了解我国对窄带ISDN业务的近期实际需求和潜在市场,有关部门在京、沪、穗三城市对ISDN业务做了缜密的调查研究。本文摘要介绍此次调查的部分结果。 相似文献
146.
Roberto?BattitiEmail author Renato?Lo?Cigno Mikalai?Sabel Fredrik?Orava Bj?rn?Pehrson 《Mobile Networks and Applications》2005,10(3):275-287
This work discusses the evolution of W-LANs from their current status of wireless termination of LAN services to a possible global infrastructure where the access networks become open to multiple operators and a vehicle of a win-win scenario, where both users and operators benefit from the new network architecture. The idea of Open Access Networks (OANs) can go beyond wireless HotSpots and be generalized to a generic shared access infrastructure that fosters service operators competition and drastically reduces the cost of last mile coverage.The general concept of Open Access Networks is detailed, highlighting its difference with the more traditional model of vertical integration of the access network into the global service. About the OANs development, it is shown how to support the quick and smooth evolution of the infrastructure toward a widespread and reliable communication support.Business models are discussed by mentioning the different actors, the market organization and the different organization forms.The final part of the paper is devoted to technical challenges such as access control, security, privacy, roaming, resource exploitation and service differentiation. As an example of how to tackle these problems, we discuss a pricing technique devoted to resource management and billing support.In addition we present a simulation on how the OAN concept can speed-up the deployment of broadband access in a real case.A preliminary version of this paper with the title “Global Growth of Open Access Networks: from WarChalking and Connection Sharing to Sustainable Business” was presented at WMASH 2003.
Roberto Battiti received the Laurea degree from the University of Trento, Italy, in 1985 and the Ph.D. degree from the California Institute of Technology (Caltech), USA, in 1990. He has been a consultant in the area of parallel computing and pattern recognition and since 1991 he has been a faculty member at the University of Trento, where he is now full professor of Computer Networks. His main research interests are heuristic algorithms for optimization problems, in particular reactive search algorithms for maximum clique, maximum satisfiability, graph coloring, networks and massively parallel architectures, code assignment in wireless and cellular networks, protocols for pricing and Quality of Service in wireless networks.Prof. R. Battiti is currently Dean of the international Graduate School in Information and Communication Technologies at Trento, Deputy Dean at the Faculty of Science, member of the advisory committee for the future Telecommunications Plan of the Autonomous Province of Trento. Prof. R. Battiti is associate editor of various scientific journals. He is the author of more than fifty scientific publications, including special issues dedicated to experimental algorithmics and wireless on-demand networks.R. Battiti is a member of IEEE Computer Society and ACM Sigmobile.
Renato Lo Cigno is Associate Professor at the Department of Computer Science and Telecommunications (DIT) of the University of Trento, Italy. He received a Dr. Ing. degree in Electronic Engineering from Politecnico di Torino in 1988. From 1989 to 2002 has been with the Telecommunication Research Group of the Electronics Department of Politecnico di Torino.From June 1998 to February 1999, he was at the CS Department at UCLA as Visiting Scholar under grant CNR 203.15.8. He is coauthor of more than 90 journal and conference papers in the area of communication networks and systems. His curent research interests are in performance evaluation of wired and wireless networks, modeling and simulation techniques, flow and congestion control, as well as network management and architecture. Renato Lo Cigno is member of the IEEE Communication Society and ACM Sigcomm.
Mikalai Sabel received his master degree in radio physics from Belorussian State University in 2002. He is now pursuing his Ph.D. at the international Graduate School of Information and Communication Technologies at University of Trento, Italy. His research interest include wireless LANs, pricing and incentive engineering, IEEE802.11 MAC protocol. His current research is focused on optimization algorithms that can provide stability and maximum global welfare in a non-cooperative environment where singles tries to maximize their own benefit function. Experimentation of such schemes to pricing techniques and micro-payments in TLC networks provides the application environment of the fundamental research.
Fredrik Orava is associate professor at KTH, Stockholm, Sweden. He conducts research into scalable (in terms of cost, capacity, number of users and devices etc.) communication system architectures and technologies. He has a MSc in engineering physics from Uppsala University and a PhD in computer systems also from Uppsala University. He previously held positions as researcher at the Swedish Institute for Computer Science (SICS); senior lecturer and manager of the telecommunications systems laboratory at the department for teleinformatics, KTH; acting professor in telecomunication systems at KTH; director for the Swedish Centre for Internet Technologies; and vice president of Dynarc AB with world wide responsibility for product management. Dynarc AB develops, manufactures and sells IP routers for optical IP networks.
Bjorn Pehrson is a professor of telecommunication systems at KTH, the Royal Institute of Technology in Stockholm, since 1992, where he has also served as a department chairman and vice dean. He had his PhD from Uppsala University 1975 where he also served as senior lecturer and established a research group in computer and communication technology. During the period 1985-1992 he participated in the establishment of the Swedish Institute of Computer Science. Björn Pehrson research interests are currently focussed on open network topologies allowing different actors forming new value chains to build networks together based on different, sometimes very local business models. The results are applied in testbeds, especially in rural areas and in developing countries.This revised version was published online in August 2005 with a corrected cover date. 相似文献
147.
In this paper, we analyze market efficiency for the Shanghai stock market over time using a model-free method known as multifractal detrended fluctuation analysis. Through analyzing the change of scale behavior, we find that the price-limited reform improved the efficiency in the long term, but the influence in the short term was very minor. Employing the method of moving window, using three different measures we find that the Shanghai stock market became more and more efficient after the reform. We also implement the same procedure on volatility series and find the evidence of inefficiency. 相似文献
148.
随着互联网络技术的飞速发展,网络聊天日益进入了人们的生活,聊天室也受到了越来越多网民的欢迎,它为网友提供了实时性交流的渠道.提出了用ASP开发基于B/S模式的聊天室系统,并对系统的设计与实现加以详细的阐述,并给出了部分关键代码. 相似文献
149.
Kostas A. Tsagkaris George Dimitrakopoulos Panagiotis Demestichas 《Wireless Networks》2009,15(3):391-405
The ceaseless evolution of wireless communications is reflected nowadays on the introduction of Beyond-3G (B3G) systems, characterized
by the coexistence and cooperation of various Radio Access Technologies (RATs), over a common infrastructure. Major facilitator
of this convergence is the advent of cognitive networks, which deploy elements (base stations and mobile terminals) that are
able to proactively adapt to environmental stimuli, so that to optimize their performance. Part of the adaptation action takes
place in cognitive base stations that own several reconfigurable transceivers, which are controlled by appropriate management
functionality and may dynamically change their operating parameters. Each reconfiguration set includes a specific RAT, carrier
frequency, as well as demand volume to be allocated per transceiver. Accordingly, proper evaluation of the various candidate
reconfiguration sets appears to be of high significance. To this effect, in this paper we consider a cognitive network segment
with transceivers operating at 3G RAT/carrier and we solve the DAMC problem (Demand Allocation into Multiple Carriers problem),
which aims at evaluating and selecting the optimum policy to allocate the demand into the available 3G carrier frequencies.
Optimality is expressed in terms of minimizing the total transmitted/received power per base station, thus deciding for the
reconfigurations with the least impact on network interference. Indicative simulation scenarios and results are also presented
for the validation and verification of the proposed functionality.
相似文献
Panagiotis DemestichasEmail: |
150.