对中国国际标准化工作的几点建议

中国政府及产业界积极参与国际通信标准化活动,有利地推动了中国由电信大国向电信强国的战略转变,中国制造的通信设备在国际市场正获得越来越多的份额.对中国通信产业界如何参与国际标准化活动并在其中取得主导地位,文章从提高参与国际标准化工作意识,利用ITU、IEC和ISO等国际权威组织,认清中国在国际标准化领域的地位,熟悉国际标准化规则和环境,强化中国知识产权工作等5个方面提出了具体建议.     

多媒体数据压缩标准化的现状与发展

信息化社会一个重要问题是“信息爆炸”,解决“信息爆炸”的方法之一是数据压缩编码技术,随着数据压缩编码技术的发展和广泛应用,许多国际组织制定了应用于不同领域的数据压缩标准。该文介绍了由国际标准化组织(ISO)和国际电信联盟(ITU)制定的视频数据压缩编码的各种国际标准及这些标准在其相应领域的应用,并指出了分析和研究一种新的国际标准的重要性。     

Capabilities of TRANSURANUS code in simulating power ramp tests from the IFPE database

Investigations of fuel behavior are carried out in close connection with experimental research, operation feedback and computational analyses. OECD NEA sets up the “International Fuel Performance Experiments (IFPE) database”, a public domain database on nuclear fuel performance experiments with the purpose of model development and code validation. The objective of the activity (performed in the framework of the IAEA CRP FUMEX-III project) is to investigate the pellet-clad interaction mechanism and the capability of TRANSURANUS code in simulating the phenomena, processes occurring in the fuel rod during the power ramps, with focus on the parameters influencing the cladding failures. The experimental database adopted is the Studsvik PWR Super-Ramp subprogram, part of the IFPE database, which consists of 28 pressurized water reactor fuel rods power ramped at burnup from 28 to 45 MWd/kgU. Relevant results by TRANSURANUS are presented in connection with the experimental evidences. Focus is given on the PCI/SCC failure, demonstrating that the failure threshold, available in TRANSURANUS, results conservative both in case of KWU and W rods.     

国际电联的电信管理网体系结构

文章简述了国际电联在其Ｍ．３０１０建议中提出的电信管理网体系结构中，即：“信息结构”，“功能结构”和“物理结构”，并预测电信管理网今后的发展方向。     

国际电联多媒体通信技术研究组研究课题

多媒体通信是近年来通信技术方面研究的特点，是目前电信界最热门和最活跃的研究方向，也是与市场结合得最紧密的研究课题。     

TMS320C54X实现ITU G.728语音编码标准

ＩＴＵ Ｇ．７２８标准晃国际电信联盟于１９９２年的一种比４特率为１６Ｋｂ／ｓ低延时ＣＥＬＰ类型语音编解码器。本文首先对Ｇ．７２８编解码算法和定点数字处理芯片ＴＭＳ３２０Ｃ５４Ｘ作了简单介绍。由于Ｇ．７２８标准是一种低延时语音编码标准,因此计算复杂度高,在实时实现中需要作特别处理。本文着重介绍了这种低延时ＣＥＬＰ（ＬＤ－ＣＥＬＰ）算法在ＴＭＳ３２０Ｃ５４Ｘ上实现的软、硬件设计和在定点ＤＳＰ芯片实现此     

Estimation of the error performance objectives for satellite communication systems

We consider the physical layer error performance parameters and design criteria for digital satellite systems established by ITU‐R Recommendation S.1062, where the performance objectives are given in terms of the bit error rate (BER) divided by the average number of errors within a cluster. It is well known that errors on satellite links employing forward error correction (FEC) schemes tend to occur in clusters. The resulting block error rate is the same as if it was caused by randomly occurring bit errors with an error‐event ratio of BER/α, where α is the average number of errors within a cluster. The factor, α, accounts for the burstiness of the errors and also represents the ratio between the BER and the error‐event ratio. This paper proposes theoretical methods to estimate the factor, α. Using the weight distributions of the FEC codes, we derive a set of expressions for the factor, α, as well as their compact lower bounds. We present lower bounds for various FEC schemes including binary BCH codes, block turbo codes, convolutional codes, and turbo codes. The simulation results show that the proposed lower bounds are good estimates in the high signal‐to‐noise ratio region. Copyright © 2008 John Wiley & Sons, Ltd.     

国际电信联盟的重大改革

本文概要介绍国际电们联盟的改革，包括：电联新机构的设置、电信标准部门和无线电通信部门的构成及其工作任务。     

ENUM发展面临的三大问题

ENUM是因特网工程任务组织(IETF）的“电话号码映射”工作组提出的一种用域名系统存储E．164号码的方法，并进一步提供如何用一个E．164号码在DNS中查找可用服务的方法。本介绍了ENUM发展的历史和现状，着重分析ENUM发展面临的号码、管理和安全隐私问题。ENUM面临的问题是传统电信网与因特网不同管理模式冲突的重要表现，具有国际和国内双重影响，如何解决这些问题不仅对ENuM这一新兴技术的发展前景有直接影响，对下一代网络管理模式也将产生重要而深远的影响。     

数字视频网络的相关标准

本文介绍了建立数字视频网络所需了解的相关标准。