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101.
In this paper we propose a new protocol called time-space label switching protocol (TSL-SP) in optical burst switching (OBS), and define the terms time-space label (TSL) and time-space routing (TSR). An important concept of response time is introduced in the time label mechanism. The TSL-SP is a new technology that can quickly and efficiently forward data with a label on the optical networks. A two-dimension label switched path (TD-LSP) can be set up, that is maintained and deleted by the TSL-SP. For clearly illuminating the operation principles of the TSL-SP, we propose a new approach of orthogonal time-space coordinates in which the vertical coordinate is the space label and the horizontal coordinate is the time label. The proposed TD-LSP can dramatically reduce the routing failure probability and greatly improve the link network efficiency compared with other signaling protocols. Moreover, we define the time-space label control plane that can achieve the higher efficiency. When the TSL-SP is applied to networks, switching performance can be improved by two orders compared to the switching performance with the conventional OBS signaling protocols. The fundamental goal of TSL-SP is to band the signaling and routing functions together closely. Also, the TSL-SP can reduce the complexity of the network, support automatic service offering, and provide traffic engineering. 相似文献
102.
XU Li~ 《中国邮电高校学报(英文版)》2004,11(4)
MANET(Mobile Ad Hoc Network)is a collection of wireless mobile nodes forming a temporary communica-tion network without the aid of any established infrastructure or centralized administration.The lifetime of a MANETdepends on the battery resources of the mobile nodes.So energy consumption may one of important design criterions forMANET.With changing the idle model to sleep model in the grid environment,this paper proposes a new energy-awarerouting protocol.Performance simulation results show that the proposed strategy can dynamic balance the traffic load in-side the whole network,extend the lifetime of a MANET,and without decreasing the throughput ratio. 相似文献
103.
Giovanni Giambene Enrico Zoli 《International Journal of Satellite Communications and Networking》2003,21(2):199-225
In this paper, we investigate a packet access scheme that is able to support mixed traffics in the presence of high propagation delays. Referring to a Time‐Code Division Multiple Access air interface, we propose a Medium Access Control (MAC) protocol based on a random access scheme. A successful attempt grants the use of a slot‐code resource. This protocol is named Adaptive Time Code‐Packet Reservation Multiple Access (ATC‐PRMA), since the access parameters are changed, depending on the traffic load conditions, so as to fulfil Quality of Service requirements. Numerical examples are carried out for the Low Earth Orbit (LEO)‐Mobile Satellite System (MSS) scenario, but all these considerations could be applied to High‐Altitude Platform Stations (HAPSs) as well. In both cases, high propagation delays prevent an immediate feedback to users. An analytical approach is proposed to study the stability of our MAC scheme. Accordingly, we define a criterion for optimizing system performance. The predicted ATC‐PRMA behaviour is supported by simulation results. Finally, we show the performance improvement of ATC‐PRMA with respect to a MAC protocol not employing adaptive parameters. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
104.
本文描述一种采用BP神经网络对雷达辐射源体制和用途进行智能识别的方法 ,包括理论分析、神经网络结构设计、推理和学习算法设计、编程算法设计、实验结果比较与分析等。实验表明 ,该方法有着良好的识别效果 相似文献
105.
106.
氨合成塔出口氨含量偏低原因分析及对策 总被引:1,自引:0,他引:1
阐述UHDE合成塔运行现状 ,分析氨净值达不到设计值的原因 ,提出相应的解决措施 相似文献
107.
Castonguay Louis G.; Schut Alexander J.; Aikens Deane E.; Constantino Michael J.; Laurenceau Jean-Philippe; Bologh Laura; Burns David D. 《Canadian Metallurgical Quarterly》2004,14(1):4
This study is a preliminary investigation of an integrative treatment aimed at improving the efficacy of cognitive therapy (CT) for depression. The development of the treatment protocol was based on process findings, which suggested that strategies used in CT to resolve alliance ruptures may actually exacerbate problems in the therapeutic relationship. The protocol integrates, within the traditional CT treatment manual, procedures to repair alliance ruptures that are derived from or consistent with humanistic and interpersonal therapies. Although conducted by inexperienced therapists, the integrative treatment led to greater improvement than a waiting-list condition. The results also compare favorably to previous findings for CT. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
自治Agents的面向服务的协商模型 总被引:3,自引:0,他引:3
提出了一个基于自治Agents的面向服务的协商模型。模型主要包括两大模块:首先定义了一系列的战略和战术过程,使得Agents可以产生初始建议,评价对方的建议,以及在此基础上做出反建议;其次,定义了两个层次的Agent通信机制。二者相辅相成,实现了Agents间合作的动态形成和随机协调,使得Agents可以承担因环境的不确定性而需动态协作的复杂任务。 相似文献
109.
The present situations of waste refrigerators recycling and disposing were analyzed. Three key technologies of layout design
of recycling plants of waste refrigerators were presented as follows: 1) establishment of recycling process of waste refrigerators;
2) the general plane layout of recycling plants; 3) the detailed layout of workshops of recycling plants. The focus of the
three key technologies is to tackle the problem of the detailed layout of workshops of the recycling plants. By adopting Petri
net, the model of logistics system of workshops was established and then optimized, and finally the detailed layout chart
of recycling plants was gained. By adopting E-factory, the recycling plants were simulated. The results show that the method
mentioned is effective.
Foundation item: Project(50375044) supported by the National Natural Science Foundation of China 相似文献
110.
Allen M. Johnson Michael A. Schoenfelder David J. Lebold 《Quality and Reliability Engineering International》1993,9(1):55-62
The Rainbow net simulation technique is applied to modelling the impact of system load and fault handling on the availability of a fault-tolerant multiprocessor architecture. Rainbow nets are described along with the motivation for creating this modelling technique. A Rainbow net fault-handling model is created for the fault-tolerant multiprocessor architecture and the topology is shown to remain constant in size, independent of the number of processor, memory and I/O elements configured in the system. Simulation is performed with a varying load in terms of the number of active jobs the system must support. Results are given showing how the fault-tolerant capability varies with load. Two new metrics for evaluating fault tolerance are introduced; namely full fault-tolerability and partial fault-tolerability. They are based on simple observations in the model. 相似文献