移动自组网选播路由协议ARAD

针对移动自组(ad hoc)网的特点,提出了一种适合ad hoc移动网络的选播路由协议——ARAD协议.该协议在充分考虑选播路由特点的基础上,将ad hoc按需距离矢量路由(AODV)协议的路由发现机制与动态源路由(DSR)协议的缓存源路由技术相结合,在动态变化的ad hoc网络中实现了一种高效的选播路由.模拟结果表明,在动态的网络环境下,ARAD协议能够取得良好的性能.     

Ad hoc无线网络路由技术的研究

路由技术是Ad hoc的关键技术,也是影响网络整体性能最重要的因素之一。对Ad hoc的路由协议进行总结性分析,并研究表驱动路由协议中的DSDV和按需路由协议中的DSR和AODV协议;结合现有协议存在的一些问题,提出相应的解决方案。     

基于能量有效的Ad hoc路由协议的研究

Ad hoc网络是一种无基础设施,由无线移动终端组成的临时多跳自治网络。本文从能量有效的目标出发,对3类不同策略的路由协议进行比较,评价各个协议之间的性能优劣。     

MPLSVPN技术安全探讨

VPN(虚拟专用网)安全方面必须是地址和路由隔离、骨干网对外界隐蔽和能预防攻击。基于MPLS(多协议标签交换)的VPN与一般第二层VPN的安全方案比较及其加强措施进行探讨.     

应用于Ad Hoc网络的时延敏感自适应路由协议

针对Ad Hoc网络中实时业务对网络平均时延的要求，提出了一种应用于Ad Hoc网络的新型路由协议——时延敏感的自适应路由协议。该协议在保持“最少跳数”的最佳路由条件下，增加了“平均最短时延”的约束条件，从而不仅可以为实时业务(即时延敏感的业务)提供可靠的路由，同时还能根据网络节点当前的业务流量，动态地选择最佳路径，降低网络的平均时延。这是一种新型的有QoS保证的路由协议。仿真结果表明，该协议的确可以有效地改善网络的性能。     

基于移动自组网的组播安全研究

Ad hoc网络已经被广泛应用,针对Ad hoc网络的安全研究也越来越普遍.针对Ad hoc网络中密钥的安全问题进行分析和讨论,指出组密钥机制存在的安全问题.最后在Ad hoc网络的ODMRP协议的基础上,提出一种组密钥生成算法,该算法比传统算法有更高的安全性和更好的生成效率.     

无线网状网路由技术与协议分析

无线网状网络是由Ad Hoc网络发展而来的一种多点对多点的无线网络,目前无线网状网络的路由协议都从很大程度上参考Ad Hoc网络的路由协议,其中经典型路由协议更是直接将Ad Hoc路由协议应用于无线网状网络环境。对经典型无线网状网路由协议进行介绍,并对其中具有代表性的协议进行重点分析。     

MPLS网络技术的发展和基本原理与应用简介

IP技术的核心架构就是路由查找算法使用最长匹配原则,递归查找,并且必须使用软件查找。而IP的本质就是"只关心过程,不注重结果"的尽力而为的服务。随着会联网技术的发展,传统的IP转发技术已经难以满足一些具有特殊需要的网络应用技术。多标签协议交换技术(Multiprotocol Label Switching,以下简称MPLS)在这种情况下应运而生。从MPLS的发展和技术实现角度,阐述MPLS技术的基本原理。     

浅谈MPLS VPN的技术特点及应用

MPLS VPN是一种基于MPLS技术的IP-VPN,是在网络路由和交换设备上应用MPLS技术,简化核心路由器的路由选择方式,利用结合传统路由技术的标记交换实现的IP虚拟专用网络(IP VPN),可用来构造宽带的Intranet、Extranet,满足多种灵活的业务需求。     

基于链路动态特征的自组网路由选择方法

针对在动态的移动ad hoc网络环境中失效路由的频繁重建和维护操作造成大量控制负载开销以及能量消耗的问题,提出了一种基于无线逻辑链路信息熵度量的路由稳定性计算方法.此算法通过网络运行过程中无线链路状态变化所表现出的不确定性特征来刻画网络节点的稳定程度,并在路由建立过程中选择相对稳定的无线移动节点作为数据传输的参与节点....     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.     

新闻(英文)

正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to     

Win-Win Cooperation

正The Chinese Premier Li Keqiang's recent trip to the UK has reinforced the China-UK comprehensive strategic partnership;just as the British Prime Minister David Cameron put it,"the relationship is gaining in strength,depth and understanding"after a bucket of business deals being inked worth more than 30 billion US dollars.From the first agreement signing in 2004 to the new agreement of mutual standards recognition and adoption in     

Systematic Approach for Emerging Industry

正A national directory of standards complexes for strategic emerging sectors was recently developed and released jointly by 12governmental departments,namely,SAC,NDRC,MOST,MIIT,MEP,MOA,AQSIQ,State Forest Administration,State Administration of Science and Technology for National Defense,State Oceanic Administration and National Railway Administration.     

Strictest Pollutants Emission Standards

正Four new national standards on air pollutant emission control offi cially issued by the Ministry of Environment Protection(MEP)together with AQSIQ and SAC has been brought into force from July 1,2014.The Emission standard for air pollutants of coal-burning,oil-burning and gasfi red boilers,which is the strictest emission standard historically,will tackle the stubborn pollution problem of boilers and waste incineration in most of China’s regions.     

Instructions to Authors

New Carbon Materials is a bimonthly journal published with the permission of the Ministry of Science and Technology and of the State News and Publication Agency.The journal is sponsored by the Institute of Coal Chemistry,Chinese Academy of Sciences,and is published by Science Press.Aims and Scope     

Progress on Standards Copyright Protection

正Recently,National Copyright Administration of China(NCAC)has rewarded 215 organizations and 179 individuals for their outstanding efforts on investigating standards copyright infringement and piracy in 2013.Hua Jianhua,the Deputy-Director of National Standards Copyright Protection Workgroup Office won a third prize of the national individual award.In 2012,SAC set up the national standards copyright protection working group,and developed policies to crack down standards infringement and piracy behaviors and to strengthen standards copyright protection.