Lantiq发布内置光控电路的GPON系统级芯片产品系列

<正>领先的宽带接入和家庭网络技术供应商领特公司(Lantiq)日前宣布推出世界首款带有内置光控电路的千兆位无源光网络(GPON)系统级芯片(SoC),该芯片应用于光网络单元(ONU)或光网络终端(ONT)。在该系列新型FALC~(TM)ON器件上集成的特性使GPON ONU/ONT制造     

GPON FEC接收机的设计挑战

<正>在ONT中选择APD还是FEC技术将对成本起决定性作用。许多GPON系统制造商极为关注这一问题,为向北美乃至世界其他地区的家庭提供三路信号播放业务(视频、语音和数据),千兆位无源光网络(GPON)成为重点考虑方案。为满足用户端的链路预算和成本目标,选择采用雪崩光电二极管(APD)接收器,还是带前向纠错(FEC)的标准接收器,目前尚存争议。     

GPON家庭网关ONT稳定性自动测试技术实现

GPON家庭网关ONT接入构成了光纤到户(FTTH)系统的支撑技术,其具有传输距离远、组网灵活、管理方便的特点,可实现多业务承载,被广泛应用于三网融合。ONT多业务的稳定性是一个关键指标,在实现GPON ONT VOIP、HSI、IPTV Triple Play业务的基础上,设计实现了多ONT并行的稳定性自动化测试平台。通过Jenkins自动触发测试,并利用思博伦网络测试仪Test Center、Abacus等进行测试验证,测试结束后自动分析测试结果、生成测试报告,并自动邮件发送。结果表明平台稳定高效,可满足多ONT并行长时间多业务测试需要,发现内存泄露问题,保证ONT业务稳定。     

GPON PK EPON

GPON标准的设计是以支持全业务(语音、数据和视频等)为出发点,不但能支持现有TDM、以太数据等业务,而且有较完备的OAM     

飞思卡尔和OpenCon共同推出GPON参考设计加速经济高效的CPE解决方案的开发

<正>联合解决方案能够加快并简化光网络终端的开发2007年11月28日,中国深圳(飞思卡尔技术论坛)——业内唯一一款支持语音的千兆无源光网络(GPON)SoC现已作为全面的硬件/软件参考设计工具箱的一部分推向市场,以促进经济的、高度集成的GPON用户端设备(CPE)的     

降低ONT应用成本——Broadlight推端到端GPON解决方案

6月1日,BroadLight公司宣布推出全面的端到端(E2E)GPON解决方案,该方案基于BroadLight的BL2000GPON System-on-Chip(SoC)器件,主要针对成本敏感ONT应用。该解决方案的推出将为客户提供低成本低风险的解决方案,加快客户ITU-T G.984兼容GPON设备推向市场的速度。“电信运营商对于GPON2.5Gbps的性能、1:64的分离比以及同时支持以太网和TDM非常感兴趣。”Infonetics Research公司首席分析师和共同创始人Michael Howard说,“BroadLight公司新推出的E2EGPON是我们目前知道的、能够帮助制造商快速生产低成本GPON产品的第一…     

电话语音产品荟萃

美国BICOM系列电话语音产品包括单板2线、4线、12线模拟,以及30线PCM数字接口板,它技术先进(板上含1～8个DSP)、扩展性强(一机可插8板)。 BICOM系列语音板可使用C语言进行开发,提供DOS、Win-dows、Windows NT环境上的API、支持TAPI标准。12线模拟、30线数字板上带有MVIP/SCSA总线接口,可与NMS及Dialogic系列产品互连互换,并提供如下优秀特性: 录放音期间可检测DTMF信号     

跨接在两个网络间的语音记录仪设计

设计了语音记录仪。该语音记录仪桥接在通信设备之间,同时提供3种桥接接口:以太网接口,支持在IP通信方式下的各通话组的直通及录音功能;二线接口,支持模拟二线方式下的直通及录音功能;音频接口,支持模拟音频方式下的直通及录音功能。同时话音记录仪提供FTP服务器,可以通过局域网对语音记录仪保存的语音文件进行下载和管理。此外,该设备支持语音回放功能。     

航电1394总线节点设计实现

机载总线节点接口模块作为系统总线网络的接入节点,其功能性能的完备性、可靠性对于总线网络系统的构建有着至关重要的作用。1394总线作为新一代飞机航空电子系统的网络传输总线,其节点模块设计的重要性不言而喻,以1394总线协议为依据,结合总线系统的需求背景,设计了一种航电1394总线节点接口模块。该模块基于标准化、通用化的设计思想,提取用户共性需求,结合1394总线协议层次结构,确定最终的产品架构。总线节点功能设计中采用CC/RN/BM一体化设计,提供PCI/PCIE主机接口,支持S100B/S200B/S400B可配置总线通信速率,设计灵活,为用户提供标准软硬件接口,有效降低了设计、维护成本。     

产品新闻

思科系统公司8月17日在京演示其面向数据、语音和视频集成网络的IP应用体系结构——Cisco AVVID。这一网络整合架构是企业未来一体化通讯网络的基础,包括统一的客户端服务、软硬件基础结构、目录服务、呼叫处理语音/数据应用、管理、服务及支持。它允许用户用现有设备把语音、数据和视频进行整合传输。而不必在向IP应用迁移中废弃已有的应用,让用户交换机PBX。同时,AVVID架构还提供了高品质的多媒体整合通信质量。 Cisco AVVID架构基于TAPI(电话应用程序接口)、JPATI(java电话应用程序接口)、MGCP(多媒体网关控制     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate