Entering the information age: implications for developing countries

The author moves from a relatively restricted view of established telecommunications services and institutions to a wider conception of information technology and considers implications for developing countries. He notes that a particularly intractable set of policy issues arises in this field. The introduction of computers and information services and their convergence with telecommunications, broadcasting, publishing, and other traditionally separate activities offer important potential gains even to very underdeveloped economies. Achieving these gains, however, requires an approach that cuts across traditional sectors and institutions and may require government guidance and initiative. Formulating and implementing such policy is much more difficult than in the traditional telecommunications sector, because informatics does not conform to established divisions of responsibility and is a relatively new field in which experience is limited. The author outlines and discusses key policy issues and offers suggestions on how they can initially be addressed     

人工智能在能源互联网中的应用综述

人工智能技术具有高效解决复杂问题的突出优点。能源互联网是信息技术与能源相结合的产物,可以为消费者提供灵活的能源共享服务。由于可再生能源具有间歇性和波动性,对可再生能源的有效利用对能源供需信息的实时性要求越来越高,能源的供需曲线也变得更加复杂多变,因此人工智能技术在能源互联网中具有广泛的应用前景。人工智能技术已经被广泛地应用于能源互联网领域中的系统建模、预测、控制和优化等方面。文章对人工智能技术在能源互联网典型应用场景的研究现状进行了综述,并对未来的发展方向进行了展望。     

Enhancing electrical engineering computer laboratory qualitythrough support evaluation

The realization of enhanced quality in electrical engineering education requires the integrated efforts of every aspect of administration, instruction, and support. Traditional evaluation activities have focused on curriculum design and instructional feedback. The role of the systematic evaluation of support services is examined. The findings of a support-specific evaluation are discussed     

Why the Ancillary Services Markets in California Don’t Work and What to Do About It

A competitive market for energy requires a competitive market for ancillary services. As California’s experience shows, the two can’t be isolated from each other. Better coordination and a portfolio approach may help.     

Congestion rents and FTR evaluations in mixed-pool-bilateral systems

Evaluation of key metrics for congestion management, including the congestion rents and the financial transmission rights (FTR) payoffs, requires the efficient allocation of transmission services and the calculation of appropriate locational marginal prices (LMPs). This requirement is particularly acute when there are bilateral transactions coexisting with the centralized pool markets. We propose a new formulation for this purpose, which captures explicitly the contribution of the bilateral transactions to the social welfare. The proposed formulation effectively integrates the pool market and the bilateral transactions on a consistent basis and results in the more efficient allocation of the transmission resources than the conventional tool. We assess analytically the capabilities of the proposed formulation and solution and quantify the improvements in the evaluations over those done using the conventional approach. Such improvements are also illustrated using simulation results on a wide range of test systems including the IEEE 118-bus network.     

Fuzzy interrupted energy assessment rate based on actual system performance

In competitive environment, customer outage cost may be taken into account for the delivery of energy services. Based on a probabilistic approach the outage cost can be evaluated from the Interrupted Energy Assessment Rate (IEAR) which normally requires customer perception on the damages occurred from an electricity interruption. In general the IEAR is only calculated based on mean values, even though the obtained customer damage information usually contains fairly large deviation. To cope with the large deviation of the data, this paper employs fuzzy arithmetic to model the customer damage function which is consequently used in association with power interruption statistics, rather than conventional probabilistic reliability calculation, to calculate the Fuzzy Interrupted Energy Assessment Rate (FIEAR). The proposed method has been tested with a distribution system of which more than 40,000 actual interruptions were recorded. The results show that the FIEAR normally covers the IEAR and provides flexibility to allow the customer outage cost to be implemented in real competitive environment.     

基于RIA技术的综合网管平台研究

随着互联网的普及以及信息通信技术的发展,基于Web部署的企业级信息应用服务已成为主流。国家电网以集中服务、集中维护和集中监控为内涵的＂大运行＂体系的构建,客观上要求电力通信网综合网管平台系统能够实现低成本的Web部署,以便于各级通信管理部门可以便捷地接入与访问。然而传统的Browser/Server（B/S）体系架构远远无法满足综合网管的交互复杂性和实时性要求。RIA（Rich Internet Application,富互联网应用程序）技术的出现使得综合网管二层部署、三层应用的建设模式成为可能。文章通过对RIA技术的研究,探讨了基于RIA技术的电力通信网综合网管系统的设计与架构。     

Predictive call admission control for multimedia streaming in CDMA cellular environments

Third-generation (3G) wireless networks based on code-division multiple access (CDMA) have been engineered to provide mobile users with voice as well as advanced packet data services. Support of Internet-based multimedia streaming services is considered a critical factor for future deployment of such networks. Provisioning streaming services in a dependable way, however, requires supporting data transmission at relatively high data rates while maintaining session quality during both intracell and intercell user movements. In this paper, an adaptive bandwidth allocation and admission control scheme is proposed for managing network resources for a streaming service. Streaming requests are assumed to be served by an adaptive server capable of choosing suitable video streaming parameters (e.g., video resolution, frame rate, and encoding parameters) in response to possible requests from the wireless network to vary the currently allocated bandwidth. The devised admission control scheme exploits a priori knowledge of user mobility patterns to minimize the risk of running into an overload condition after acceptance of a new multimedia streaming connection. The obtained simulation results show that, compared to a nonpredictive admission control scheme, the proposed scheme achieves a lower forced-termination probability and higher throughput, while consuming less base-station transmission energy.     

IEC 61850快速报文传输服务在VxWorks中的实现

采样值和通用面向对象的变电站事件(GOOSE)报文是IEC 61850标准中实时性要求最高的2种通信服务(以下简称为快速报文传输服务)。不同于VxWorks默认采用的传输控制协议(TCP)/互联网协议(IP)协议栈,快速报文传输服务要求直接由应用/表示层映射到数据链路层。针对这一问题,在分析快速报文传输服务的抽象通信服务接口(ACSI)和特定通信服务映射(SCSM)的基础上,在VxWorks中设计了实现快速报文传输服务的快速通信接口、应用任务与函数,继而提出了快速报文传输服务的实时处理方法,最后组建了测试环境对GOOSE报文的实现及其实时性进行了测试。     

A distributed information repository for autonomic context-aware MANETs

Due to the emergence of multimedia context-rich applications and services over wireless networks, networking protocols and services are becoming more and more integrated, thus relying on context and application information to support their operation. Further, wireless protocols and services now employ information from several network layers and the environment, breaking the layering paradigm. In order to cope with this increasing reliance on information, we have proposed MANIP, a middleware for MANETs that instantiates a new networking plane. The Information Plane (InP) is a distributed entity to store and disseminate information concerning the network, its services and the environment, orchestrating the collaboration among cross-layer protocols, autonomic management solutions and context-aware services. We use MANIP to support the autonomic reconfiguration of a P2P network over MANETs. Simulation results show that the MANIP-enabled solutions reduce the response time and increase the number of solved P2P queries when compared to classic, cross-layer implementations of the same protocols.     

ICT网络模式的关键技术与发展

信息通信技术（ICT）要求信息网络与通信网络融合在一个网络平台上,同时提供数据信息传输、音视频会议、电话、传真、即时通信等多种类型的应用服务。文章介绍了有关ICT网络模式的OTN,T-MPLS,ION,ASON,IMS,xPON,4G,LTE,PLC等关键技术及国内外研究与应用情况,为ICT技术在电力系统的深入研究与应用提供借鉴。     

OFDM系统信道估计算法研究及其在低压电力线通信上的应用

低压电力线通信以其特有的优势将在未来高速数据通信业务中发挥重要的作用，OFDM(正交频分复用)技术具有很强的抗多径能力，非常适合低压电力线通信的多径信道传输。采用相干解调的OFDM系统需要对信道进行估计，以获得信道状态信息(CSI)。文中分析比较了OFDM系统信道估计算法，并根据低压电力线信道的特点，选择了适合于电力线通信的信道估计方法。     

电力设计企业向工程公司转型的组织机构研究

面对新的能源结构调整,以及更加集成化的工程建设环境,作为智力密集型的传统电力设计企业不得不调整自身的组织结构,向产业链条横向和纵向更加延展的工程公司转型.这种转型对现有企业的项目开发能力、工程建设能力、管理优化能力以及售后服务能力都提出了更高的要求,对于这些新能力的引导,需要能够服务于工程建设全产业链的组织机构作为坚实...     

Time and Cost-Driven Scheduling of Data Parallel Tasks in Grid Workflows

The necessity of identifying suitable computing resources to solve a scientific or engineering problem in a Grid environment requires more and more sophisticated resource management systems: 1) strategies and technologies should be able to master the complexity of modern large-scale networks and computing facilities and 2) the convergence of Grid computing toward the service-oriented approach is fostering a new vision where economic aspects represent central issues to burst the adoption of computing as a utility. In this context, the design and execution of data and compute-intensive applications are often simplified by the adoption of model-driven approaches based on workflows. The execution of Grid workflows can leverage on meta-scheduling systems to automatically and transparently allocate tasks to resources that ensure the fulfillment of functional requirements and quality-of-service (QoS) constraints, specified by the user. This paper presents a time and cost-constrained scheduling strategy that, according to the data parallelism pattern, is able to deploy scientific and business workflow tasks (or other kinds of application tasks) on pools of resources selected with the aim of minimizing the overall execution time. The strategy was implemented as a plug-in in a matchmaker for Grid services and its validity and accuracy were experimentally proved on a real testbed leveraging a framework for the deployment of data parallel tasks. The results show that the tasks deployment is effective and accurate and pave the way for using the Internet as a utility computing facility.      

电力系统嵌入式NTP授时服务器设计与实现

随着电力系统规模的扩大以及电力系统控制技术的发展,时间同步变得越来越重要。NTP网络授时服务作为电力系统时间同步中一项重要的方式。因此,设计一个高精度的NTP服务器为电力系统提供授时服务是十分重要的。本文以AT91RM9200处理器为硬件核心,嵌入式Linux系统为软件核心,设计了电力系统NTP授时服务器。经试验证明,授时精度高,系统运行稳定。     

Comparison of ANSI and IEC 909 short-circuit current calculationprocedures

A generalization of the methods used by both ANSI and IEC 909 is presented. The philosophical differences in calculation procedures are discussed. Although ANSI fault calculation methods are designed to determine a value to compare with the equipment ratings, the IEC 909 Standard presents a method that inherently more accurately models the fault currents that flow. The IEC method requires significantly more complex modeling of the power system fault contributions than the ANSI method requires. By understanding the calculation differences, the difference in equipment ratings becomes more meaningful     

电网企业云计算技术应用

“十二五”期间,国家电网公司提出了建设坚强智能电网和三集五大体系的重大举措,这就要求信息、通信进一步全面提升,因此启动SG-ERP工程建设.“十二五”的信息化建设需要云计算技术的支撑.文章提出了适合电网企业现有IT基础设施的云计算技术框架并分析了引入云计算的预期成效.电网企业将通过云计算技术降低系统建设和运营成本,提高信息处理能力,实现IT服务创新,增强企业核心竞争力.     

Service Clouds: Distributed Infrastructure for Adaptive Communication Services

This paper describes service clouds, a distributed infrastructure designed to facilitate rapid prototyping and deployment of adaptive communication services. The infrastructure combines adaptive middleware functionality with an overlay network substrate in order to support dynamic instantiation and reconfiguration of services. The service clouds architecture includes a collection of low-level facilities that can be invoked directly by applications or used to compose more complex services. After describing the service clouds architecture, we present results of experimental case studies conducted on the PlanetLab Internet testbed alone and a mobile computing testbed.     

Services: A System's Perspective

A system's perspective of services is contained herein. Analogous to manufacturing, services can and should also be viewed from a system's perspective. While the interdependences, similarities, and complementarities of manufacturing and services are significant, there are considerable differences between goods and services, including the shift in focus from mass production to mass customization (whereby a service is produced and delivered in response to a customer's stated or imputed needs). In general, a service system can be considered to be a combination or recombination of three essential components-people (characterized by behaviors, attitudes, values, etc.), processes (characterized by collaboration, customization, etc.), and products (characterized by software, hardware, infrastructures, etc.). Furthermore, inasmuch as a service system is an integrated system, it is, in essence, a system-of-systems (SoS) which objectives are to enhance its efficiency (leading to greater interdependency), effectiveness (leading to greater usefulness), and adaptiveness (leading to greater responsiveness). The integrative methods include a component's design, interface, and interdependency; a decision's strategic, tactical, and operational orientation; and an organization's data, modeling, and cybernetic consideration. A number of insights are also provided, including an alternative SoS view of services; the increasing complexity of systems (especially service systems), with all the attendant life-cycle design, human interface, and system integration issues; the increasing need for real-time, adaptive decision making within such an SoS; and the fact that modern systems are also becoming increasingly more human-centered, if not human-focused-thus, products and services are becoming more complex and more personalized or customized.     

Wind generation imbalances penalties in day-ahead energy markets: The Italian case

Today there is a lot of interest in wind energy exploitation. It has been emphasized by adopted incentive mechanisms and by the possibility to sell energy to the electrical market in different ways. The rise of wind installed power requires more energy for ancillary services. Moreover, imbalance costs have to be sustained by the Transmission System Operator (TSO) which could charge them to all the consumers where wind power producers are not penalized for their imbalances. To solve this problem some solutions can be adopted depending on market rules that are different from one country to another. In particular referring to the current Italian market framework and taking into account to the state-of-the-art wind power forecasting, an economic assessment of imbalance for some wind farms have been compared to balancing costs of the TSO. Different stochastic approaches have been adopted, using available historical data, in the analysis of various scenarios both for the TSO and for wind plant owners. Also possible mechanisms for imbalance settlements have been proposed in order to maintain grid safety costs within a reasonable level for electricity consumers, and to avoid an excessively penalizing treatment for wind energy source investments in order to satisfy environmental targets of the European Community.