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141.
Tao Zhang Eric van den Berg Sunil Madhani Ashutosh Dutta Shantidev Mohanti 《Wireless Networks》2007,13(5):617-633
Mobile users and devices want to discover and share a growing range of information as the processing and storage capabilities
of mobile devices grow. For example, users want to discover nearby networks, and location-based or time-sensitive user information
contents. A mobile device may want to discover neighboring networks and the parameters required to access these networks so
that it can intelligently decide which networks to use next, and use its existing network connection to authenticate with
selected neighboring networks before it moves into the coverage areas of the selected networks. This can significantly reduce
handoff delays. Existing service discovery frameworks are not effective for such neighboring network discovery or for discovering
dynamic, location- or time-sensitive user information contents. This paper describes and evaluates a new approach—Mobile Information
Services enabled by Mobile Publishing (MIS-MP)—for real time collection, discovery, and sharing of network and user information.
With MIS-MP, mobiles take full advantage of the wealth of information they can accumulate during their routine mobility and
use of networks to help each other to discover the information they want when and where they want it. This is accomplished
by mobiles publishing the information they collect about the networks they visited, and the user information contents they
learned or used, to make the information available to other mobiles. This paper presents analytical models and simulation
results to evaluate the feasibility and performance of MIS-MP. It also describes a testbed implementation of MIS-MP and some
of the lessons we learned.
Tao Zhang is Director of Mobile Networking Research Group at Telcordia Technologies, Piscataway, New Jersey, USA. He develops and directs
research and advanced development programs in mobile networking and applications, including mobility and applications across
heterogeneous radio networks, mobile information services, vehicular networking, mobile peer-to-peer applications, sensor
networking and applications, and collaborative networking .Dr. Zhang’s work has led to several new commercial products. He
co-authored the book “IP-Based Next Generation Wireless Networks” published by John Wiley & Sons in 2004. He initiated the International Conference on Collaborative Computing: Networking,
Applications, and Worksharing (CollaborateCom), and has been serving in various roles for it. Dr. Zhang holds 4 U.S. patents,
with over 25 more pending. He received the 2000 Telcordia CEO Award (for most exceptional teams and individuals who have achieved
a significant business success) and 2002 SAIC’s Executive Science and Technology Council Publication Prize.
Eric van den Berg received his Ph.D. in Applied Mathematics from Cornell University in 1999. After obtaining his degree, he joined Telcordia
Technologies, where he is a Research Scientist in Applied Research Department. His research interests include traffic modeling
and performance analysis of IP- and wireless networks. He received the 2000 Telcordia CEO Award (for most exceptional individuals
and teams who have achieved a significant business success) and the 2002 SAIC Executive Science and Technology Council Publication
Prize.
Sunil Madhani is a Distinguished MTS with Motorola where he manages the IP Realization team in Mobile Device Technology Office. He aims
at working on unconventional and disruptive IP technologies. His current research focus is on convergent networks, dynamic
mobility management and fast handoff in secured/seamless wireless LAN/WAN roaming. His past research includes registration/configuration
protocols in wireless environment, application layer mobility management, secured Mobile IP, managed DOS attack sensor and
TCP/IP boosters. Sunil Madhani holds MS (2002) in Engineering Management & System from Columbia University and MS (1997) in
Computer Science from State University of New York. 相似文献
142.
A general synthesis procedure is given for a versatile signal flow graph realization of a general transfer function by using current differencing buffered amplifier (CDBA). The proposed configuration uses n+1 CDBAs, n capacitors and at most 2n+4 resistors. This number of resistors can be reduced to n+1 for special cases. The circuit is eligible to obtain a variety of transfer characteristics with the same common denominator polynomial, and it is easily converted to different modes of operations. It is straightforward to find the values of the passive elements from the coefficients of the transfer function to be realized. Simulations results are obtained by using commercially available active component AD844 and CMOS technology as well. All of these make the proposed circuit attractive. 相似文献
143.
A protocol of quantum secret sharing between multiparty and multiparty with four states was presented. It was shown that this
protocol can nullify the Trojan horse attack with a multi-photon signal, the fake-signal attack with Einstein-Podolsky-Rosen
pairs, the attack with single photons, and the attack with invisible photons. In addition, the upper bounds of the average
success probabilities were given for dishonest agent eavesdropping encryption using the fake-signal attack with any two-particle
entangled states.
Supported by the National Natural Science Foundation of China (Grant No. 10671054), the Key Project of Science and Technology
Research of Education Ministry of China (Grant No. 207011) and the Natural Science Foundation of Hebei Province, China (Grant
Nos. A2005000140 and 07M006) 相似文献
144.
In this work we have performed a detailed analysis, using signal processing tools, to study time series of data (temperature proxy) extracted from the GRIP ice-core records and we relate it with the evolution of atmospheric CO2 within the last glacial period. Our method is based in considering the warm periods known as Dansgaard–Oeschger (D/O) events and posterior returns to the cold stage as a climatic cycle. After the warming phase, D/O events relax to the initial cold state in three different ways, what gives rise to three classes of cycles. Also, the Younger/Dryas–Bolling/Allerod (Y/D–B/A) cycle corresponds to one of the classes obtained. We have found that all cycles start with identical warming phases which seem completely unrelated to variations in CO2 concentration. We discuss on the consequences for global climatology of such steady pattern of cycles. 相似文献
145.
高速PCB串扰分析及其最小化 总被引:6,自引:0,他引:6
技术进步带来设计的挑战,在高速、高密度PCB设计中,串扰问题日益突出。本文就串扰原理和对信号完整性影响进行分析,并在此基础上提出了高速PCB设计中串扰最小化的方法。 相似文献
146.
Yang Li Jian Dong Ke Chen Wei Guo 《International Journal of Infrared and Millimeter Waves》2008,29(7):663-672
This paper presents a signal-level simulation model for simulating the process that antenna array of Aperture Synthesis Radiometer
(ASR) collecting thermal radiation and transforming thermal radiation signal into radio frequency (RF) signal. By using the
equivalent complex baseband signals to represent the practical thermal radiation and RF signals, simulation efficiency is
improved significantly. The statistic characteristics of simulation results are found to match the corresponding theoretical
analysis well. Results of an imaging simulation experiment show that this model can be employed in ASR system-level simulator
design. 相似文献
147.
We prove a uniqueness theorem for two non-constant meromorphic functions sharing three values which improves a recent result of T.C. Alzahary. As a consequence of our main result we also improve a theorem of G. Brosch. 相似文献
148.
线路共享指的是,用户除了从自己归属的本地电话公司(ILEC)以外还能选择从其它运营公司(主要指CLEC)为自己提供数据业务,并且不必安装第二条电话线。线路共享为现有电话线路上开展数据业务竞争铺平了道路,它在美国被视作能否成功开放DSL市场的关键因素。本文对美国针对DSL发展问题出台线路共享政策以及线路共享政策出台后的实施状况加以报道。对于我国制定线路共享政策和实施管理提供参考。 相似文献
149.
150.
D. V. Rogers J. E. Allnutt 《International Journal of Satellite Communications and Networking》1986,4(1):1-11
Exploitation of the international 14/11 GHz communications bands will probably follow the same pattern as that of the 6/4 GHz bands. First, the available monopolarized bandwidth will be filled. Next, multiple beams that use spatial isolation to provide frequency reuse will be developed. Finally, full dual-polarized operation will be employed. In the 14/11 GHz bands, rain can cause appreciable attenuation and depolarization. In some instances, dual polarized links will be depolarization limited. If up-link power control is implemented on attenuation dominated paths, depolarization can again dominate, owing to interference constraints. In both cases, a measure of depolarization compensation needs to be introduced to reduce the impact of interference. Part I of this paper quantifies this problem and establishes a set of reference statistics which can be used to assess the need for impairment restoration. Part II will discuss several ways of reducing the system impact of path depolarization. 相似文献