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排序方式: 共有674条查询结果,搜索用时 15 毫秒
61.
62.
Rosario G. Garroppo Stefano Giordano Davide Iacono Luca Tavanti 《Wireless Networks》2011,17(6):1441-1459
In WiMAX systems the Base Station scheduler plays a key role as it controls the sharing of the radio resources among the users.
The goal of the scheduler is multiple: achieve fair usage of the resources, satisfy the QoS requirements of the users, maximize
goodput, and minimize power consumption, and at the same time ensuring feasible algorithm complexity and system scalability.
Since most of these goals are contrasting, scheduler designers usually focus their attention on optimizing one aspect only.
In this scenario, we propose a scheduling algorithm (called GTSN\mathrm{GTS_N}) whose goal is to contemporaneously achieve efficiency and fairness, while also taking into account the QoS requirements
and the channel state. GTSN\mathrm{GTS_N} exploits the properties of Time Utility Functions (TUFs) and Game Theory. Simulations prove that the performance of GTSN,\mathrm{GTS_N}, when compared to that of several well-known schedulers, is remarkable. GTSN\mathrm{GTS_N} provides the best compromise between the two contrasting objectives of fairness and efficiency, while QoS requirements are
in most cases guaranteed. However, the exponential complexity introduced by the game theory technique makes it rather impractical
and not computationally scalable for a large number of users. Thus we developed a suboptimal version, named sub-GTSN.\mathrm{GTS_N}. We show that this version retains most of the features and performance figures of its brother, but its complexity is linear
with the number of users. 相似文献
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66.
Aicardi M. Davoli F. Giordano A. 《Selected Areas in Communications, IEEE Journal on》1989,7(2):219-225
A solution for the connection of personal computers or workstations to a central station (represented by a mainframe or a server attached to a local area network) by means of a shared radio channel is presented. Issues regarding the multiple-access protocol are discussed, and an access scheme that is based on the independent stations algorithm (ISA) is presented. The necessary modifications of the basic ISA are discussed, and the overall algorithm is analyzed and tested by simulation. An implementation that is currently being developed is briefly described, focusing on the choices made for the logical link control protocol, the transmission techniques, and the interface software 相似文献
67.
V. Alderucci E. Passalacqua N. Giordano P. L. Antonucci F. Parmigiani N. Ricci 《Journal of Applied Electrochemistry》1990,20(2):235-239
This paper reports the experimental evidence for morphological changes that occur at the electrodes of phosphoric acid fuel cells (PAFC) under very severe (OCV) conditions. In addition, the dissolution of Pt-supported crystallites in H3PO4 is demonstrated by Transmission Electron Microscopy (TEM) confirming previous results already reported in the literature. Finally, the experimental data are discussed on the basis of an analysis of the reaction rates and models for the corrosion mechanism is postulated. 相似文献
68.
Measurement is made of the first-sound generation and detection efficiencies of vibrating superleak transducers (VSTs) operated in superfluid4He. This is accomplished by using an ordinary pressure transducer to generate first sound with a VST as the detector, and by using a pressure transducer to detect the sound generated by a VST. The results are in reasonably good agreement with the current theory of VST operation. 相似文献
69.
Multihop Ad Hoc Networking: The Reality 总被引:1,自引:0,他引:1
In this article we show that, although pure general-purpose MANET (mobile ad hoc networks) does not yet exist in the real world, the multihop ad hoc networking paradigm was successfully applied in several classes of networks that are penetrating the mass market. We present as examples mesh, opportunistic, vehicular, and sensor networks, where the multi-hop ad hoc paradigm is applied in a pragmatic way to extend the Internet and/or to support well-defined application requirements. We contrast these successful areas of ad hoc networking to the lack of impact of pure general-purpose MANET, demonstrating how a more pragmatic approach is a winner 相似文献
70.
Rosario G. Garroppo Stefano Giordano Michele Pagano 《International Journal of Communication Systems》2002,15(10):851-866
The paper presents an analytical study aimed to establish a dimensioning procedure for the token bucket algorithm, used as a meter in a Differentiated Services network architecture, when a stochastic model for the multiplexed traffic is available. In the work, we propose an equivalent queueing system method to ‘on line’ estimate the linear bounded arrival processes (LBAP) parameters when a non‐zero probability of non‐conforming packets is accepted. Then, we validate our approach considering an aggregation of fluidic On‐Off processes with exponentially distributed sojourn time in each state, used to model telephone sources with voice activity detection (VAD). To test the goodness of our analytical results, we employ discrete event simulations, which have highlighted the accuracy of the proposed dimensioning procedure in a voice over IP (VoIP) scenario. Moreover, we investigate the multiplexing gain and the effect of different parameters on the LBAP characterization of the VoIP traffic, taking into account a non‐zero probability of non‐conforming packets. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献