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1.
支持PSTN向NGN演进的协议——BICC   总被引:1,自引:0,他引:1  
在传统电信网向下一代网络(NGN)的演进过程中,为了既能实现与现有网络的兼容,又可以实现对任何分组网络的承栽,ITU—T提出的承载无关呼叫控制协议——BICC成为目前的一个研究热点。首先介绍了BICC的体系架构与功能模型,接着分析了BICC的呼叫流程,最后给出了如何实现BICC对IP网络的承载控制。  相似文献   

2.
随着互联网技术的发展,特别是基于互联网Voip技术不断的实践,各大运营商出于网络成本及新业务提供等各种不同目的,将NGN技术应用于电信级网络。NGN是基于IP分组技术,业务与呼叫完全分离,呼叫控制和承载完全分离,融合语音、数据、多媒体和移动业务的网络。本文结合营口网通软交换建设实践,主要对NGN架构进行了详细论述,并对固网运营商实现软交换后,业务能力的提升进行了阐述。  相似文献   

3.
呼叫接纳控制是通讯网络设计与运营中的一个重要优化问题. 环网络中,这一问题的目标是对于给定的具有边容量的环网络和任意利润的呼叫的集合,确定最大利润的呼叫子集并为其中每一个呼叫安排路径,使得任一边容量不被违反. 对于无向和有向环网络呼叫接纳控制问题, 均给出了多项式时间近似方案.  相似文献   

4.
基于软交换(SoftSwitch)领域中网间互通(Interworking)技术的发展,通过对ITU-T组织提供的建议(Q.1912.5,TRQ.2815)的分析,介绍了SIP与BICC/ISUP互通的技术实现规范以及需求,为实现IP网络与PSTN/PLMN的互通提供一种可行的解决与实现方法.  相似文献   

5.
为了实现在智能公用电话上提供各种增值业务,使公用电话也可以访问互联网上的服务,提出了将PSTN网络和IP网络相结合,由语音接入平台、数字运营平台和增值业务平台三部分组成的智能公话系统平台·系统采用了软交换的思想,将呼叫控制与业务承载相分离,增值业务平台可以通过服务提供商接口随时加入新的增值业务·阐述了智能公话系统平台的设计与实现,并进行了平台的性能分析·  相似文献   

6.
提出了3G系统中软切换双队列机制的多业务接入控制策略,对不同业务给予不同的优先权,根据网络的不同状态控制语音或数据切换呼叫、语音或数据新呼叫入网;尤其采用软切换双队列机制,保证了有用的虚假切换请求不丢失,从而有效降低切换呼叫的切换失败概率.实验结果表明,该方法硬件实现简单并能动态分配移动通信网络资源,有效地保证移动通信网络中切换业务的服务质量;该接入控制策略具有切换呼叫等待处理时间短,切换失败概率低等特点.  相似文献   

7.
要实现端到端的QoS既需要接入网、核心网和外部网络的不同域间的共同保证,还需要承载层和业务应用层的相互配合。IMS是建立在承载网络基础上的控制层网络,采用基于策略的机制提供QoS控制。IMS基于策略的架构就是为了要提供不同域间、上下层间的相互协同。介绍了IMS QoS支持机制,描述了IMS QoS的体系结构及信令控制流程,分析了该架构的不足之处,并提出了相关的改进方案。  相似文献   

8.
赵刚 《科技信息》2011,(29):I0075-I0076
软交换是把呼叫控制功能从媒体网关中分离出来,通过服务器上的软件实现基本呼叫控制功能,它具有伸缩性强、接口标准、业务开放等特点,发展极为迅速。软交换作为网络发展的必经阶段,被中石化管道储运公司正在适时地引入到网络中。本文将对软交换在中石化管道储运网中的应用和网络发展进行分析和探讨。  相似文献   

9.
呼叫切换技术作为提高移动网络服务质量的关键,是目前移动网络技术的一个难题.为解决用户位移导致的服务器之间呼叫切换问题,通过对软交换技术及SIP协议的深入剖析,设计并实现了基于软交换技术的IPH呼叫切换系统.对IPH系统的总体架构、功能接口、状态转换及特殊消息类等关键问题进行了详细阐述,并使用WiFi-GSM双模手机对该...  相似文献   

10.
SIP协议是下一代网络(NGN)中的重要协议,本文对SIP协议的结构及实现方法等做了概要介绍,在此基础上将SIP协议栈应用于BCM1101的VoIP网关系统中,采用开放源代码的SIP协议栈oSIP实现呼叫控制,并且扩充oSIP协议栈的REFER功能,实现多方会议控制.该系统具有广泛的适用性和良好的可扩展性等优点.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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