新一代应急综合通信系统的构建

从应用和技术角度分析了应急综合通信系统的需求,提出了基于IP技术的综合网络通信平台——应急综合通信系统的构建方法,有效解决了目前城市应急联动系统亟待解决的3个问题:①传统的电话、VHF/UHF/HF无线电、新一代无线数字集群、VSAT卫星、移动电话网GSM/GPRS、计算机网络综合通信与互通互联;②移动(车载)指挥中心的综合通信;③指挥中心(包括固定和移动指挥中心)间的互联互通。     

Managing a portfolio of long term service agreements

Long-term service agreements (LTSAs) for the maintenance of capital-intensive equipments such as gas turbines and aircraft engines are gaining wide acceptance. A typical LTSA contract spans over a period of around 10 years making a manufacturer fully responsible for maintaining the customer equipment. In this paper, we address the management of a portfolio of such contracts from the manufacturer’s perspective. The goal is to meet all the service requirements imposed by the contracts while minimizing total cost incurred. We develop a deterministic integer programming model to generate the optimal maintenance schedules that minimize the total portfolio cost. We then propose two heuristic algorithms for the problem.     

The tightness in the ergodic analysis of regenerative queueing processes

The tightness of some queueing stochastic processes is proved and its role in an ergodic analysis is considered. It is proved that the residual service time process in an open Jackson-type network is tight. The same problem is solved for a closed network, where the basic discrete time process is embedded at the service completion epochs. An extention of Kiefer and Wolfowitz's “key” lemma to a nonhomogeneous multiserver queue with an arbitrary initial state is obtained. These results are applied to get the ergodic theorems for the basic regenerative network processes. This revised version was published online in June 2006 with corrections to the Cover Date.     

智能网CS-2阶段提供的业务和能力

本文简要介绍了智能网第2功能级(IN CS-2)所提供的3类业务及其业务特征,并从智能网概念模型(INCM)的角度,论述了 CS-2所具有的能力,着重介绍了 CS-2与 CS-1相比较所增加的功能实体及功能实体间的关系。     

Performance analysis of congestion avoidance algorithms with non‐zero MCR guarantee for ABR service in ATM networks

This paper proposes a novel explicit rate allocation algorithm called Fast Rate Allocation Congestion Avoidance (FRACA) algorithm supporting non‐zero minimum cell rate (MCR). The non‐zero MCR guarantee strategy for ABR service in ATM networks focused in this paper is MCR plus equal share (The ATM Forum Traffic Management Specification, version 4.0. April 1996). The main goals for designing the algorithm are the fast convergence according to the max–min fairness criteria, fairness among all sessions, maximum network utilization while the switch queue length is properly controlled. At the same time, it should work well under a wide range of network conditions without the need for adjusting the algorithm parameters. The performance of the proposed algorithm is evaluated and compared with the Generic Weighted Fairness (GWF) ERICA + (J Comput Comm 2000; 149). Simulation results show that the proposed algorithm achieves the design goals in the evaluated scenarios. Copyright © 2004 John Wiley & Sons, Ltd.     

从电信业价值链的演变看电信增值业务的发展及监管

竞争加剧、市场细分使得传统的电信业务价值链由原来简单的几个环节逐渐向复杂、多环节发展。垒球通信业的发展使得运营商、制造商都在寻求新的业务收入增长点：新的价值链已初现端倪并在逐步完善发展中。本文从电信业近年的价值链演变分析入手，对当今电信增值业务的发展及其监管提出初步探讨。     

宽带业务持续发展策略研究

文章认为以即时通信(IM)为代表的互联网新业务比以往更强烈地冲击着传统电信业务和运营模式,电信运营商发展宽带业务的思路应跟上形势的变化.文章探讨了电信运营商宽带业务发展策略,提出电信运营商应定位于成为电信级公共业务平台运营商,应关注下一代业务交付平台的发展,应加强对宽带业务持续发展的重要驱动力--非PC宽带终端的研究与开发.     

Remarks on the remaining service time upon reaching a target level in the M/G/1 queue

In this note we establish connections between new and previous results on the remaining service time upon reaching a target level in the M/G/1 queue.     

Web空间要素服务中的复杂要素建模与实现

介绍了一个复杂空间要素建模方法与Web空间要素服务系统,探讨了复杂要素类型的自定义规则,并针对多数据源的空间要素数据查询介绍了查询算法和优化策略。     

基于综合业务数据库的智能网设计方案

提出了综合业务数据库系统的设计方案,数据库系统的设计采用软件总线思想,模块化的设计,通过实现SCP,SDP,SMP,SCEP的功能,为用户提供标准的智能网业务,定制各种增值业务,并能满足下一代网络NGN的智能业务应用.