UML系统模型的组织

用UML对系统建模，可能要产生大量的描述系统模型的制品。说明了如何从系统的观点组织模型，并阐述了系统、子系统、视图和模型间的关系。     

微波通信站的防雷保护

本文介绍了由三个子系统构成的微波通信站防雷保护系统及其保护措施。三个子系统分别起到将绝大部分雷电流直接引入地中泄散、阻塞侵入到设备上的雷电波以及限制被保护物上的雷电过电压幅值的作用。这三个子系的作用是互相配合，各司其职，缺一不可的。     

智慧园区设计概要

新技术、新产品、新的子系统正在不断地被应用到智能化建设中,建筑智能化程度的高低已经在很大程度上决定建筑物的档次。该文以一个包含酒店以及商住的园区为例,提出了智慧园区的概念和智慧园区的设计理念。通过对酒店以及商住部分各子系统功能的介绍,使得智慧园区的建设有章可循;同时文章也提出了智慧园区建设将面临的挑战,使得读者对智慧园区的理解和认识更加直观和客观。     

某型车载式地空导弹武器系统效能分析

通过定义相关参数,将某型车载式地空导弹分为战时不可修复的3个子系统：弹体、雷达、地面发控设备,逐一运用WSEIAC模型进行效能分析,在此基础上推出全系统的效能,使全部计算既合理又简便。     

VSS based session setup mechanism in IMS

This paper proposes a novel session setup mechanism in IMS (IP Multimedia Subsystem) by introducing the functional entity termed VSS (Visitor Subscriber Server) which is used to provide registration and location management. The new mechanism aims at improving session setup procedure by a betterment of location management in IMS. Through the use of two-tier subscriber information database constituted by the HSS (Home Subscriber Server) and the VSS, the new mechanism seperates the registration procedure and location management from the S-CSCF (Serving-Call’Session Control Function), and makes them be handled by the VSS. At the same time, the new mechanism updates the signaling procedure of registration and session setup. With VSS based location management, the cost of registeration and session setup procedure as well as the delay of session setup procedure become lower. The cost and delay functions of the new session setup mechanism as well as the cost function of new registeration are deduced. Then, simulations and analysis verify that the performance of this new mechanism gets the benefit in cost and time.     

一种新的IMS分布式SCIM业务触发机制

IMS(IP Multimedia Subsystem)网络中,S-CSCF(Serving Call Session Control Function)逐次匹配过滤准则的业务触发机制使呼叫信令在S-CSCF与AS(Application Server)之间多次转发,增加了S-CSCF实体的负载压力和呼叫延迟时间。该文在现有IMS业务提供框架的基础上,提出分布式SCIM(DSCIM)业务触发机制,完成了业务流程中AS到AS的连续业务触发,避免了S-CSCF与AS之间信令的往返转发。通过Jackson排队网络理论对业务触发机制进行了数学模型分析和仿真实验,结果均表明DSCIM业务触发机制能够有效降低网络的平均呼叫时延,减轻S-CSCF的负载压力。     

电信业IMS发展研究

通过探讨分析电信业全业务运营发展的必然趋势,揭示FMC作为电信业全业务发展的必然选择。目前,IMS已成为业界认可的支持固定接入和移动接入的统一核心控制网络;本文重点分析研究了基于IMS实现融合网络的技术架构、使用的角度和优势、运营商转型、应用部署情况、面临的问题和思考。     

网络融合的趋势分析和展望

下一代网络业务、控制、承载、接入分离的思想为未来网络融合提供了统一的架构。网络融合包括业务融合、核心网络融合、接入网络融合、终端融合、运维融合等多个方面。未来融合网络的发展趋势将是在核心控制层采用IP多媒体子系统(IMS),在核心承载层采用因特网协议/多协议标记交换(IP/MPLS)技术,在业务层采用统一开放的业务提供架构,在接入层支持固定、移动、窄带、宽带等多种接入技术,终端则呈现多模化和智能化的趋势,最终实现一个用户、一个号码、一个终端、一个账单、一个核心网络、随时随地享受的全业务模式。     

IMS统一控制CS域补充业务可行性研究

通过对网络发展分析,提出了IMS统一控制CS域补充业务的必要性和具体的方案,对方案的可行性进行了分析。     

On performance of application triggering architecture in IMS network

The modeling of Application Triggering Architecture (ATA) in the IP Multimedia Subsystem (IMS) is presented. The session setup delay and system throughput are employed as the measurement to investigate the performance of ATA and the Serving Call Session Control Function (S-CSCF). With theoretical analysis and simulation results, we find that, the number of the ASs (Application Servers), the use of the subsequent Filter Criteria (sFC) and the arrival rate have heavy impact on the session setup delay and the S-CSCF is the major bottleneck in IMS network. The results are useful in constructing IMS network. At last, we propose several possible solutions to reduce the session setup delay and decrease the load of the S-CSCF.