A Survey on Communication Networks for Electric System Automation

Published in Computer Networks 50 (2006) 877–897, an Elsevier journal. The definitive version of this publication is available from Science Direct. Digital Object Identifier:10.1016/j.comnet.2006.01.005In today’s competitive electric utility marketplace, reliable and real-time information become the key factor for reliable delivery of power to the end-users, profitability of the electric utility and customer satisfaction. The operational and commercial demands of electric utilities require a high-performance data communication network that supports both existing functionalities and future operational requirements. In this respect, since such a communication network constitutes the core of the electric system automation applications, the design of a cost-effective and reliable network architecture is crucial. In this paper, the opportunities and challenges of a hybrid network architecture are discussed for electric system automation. More specifically, Internet based Virtual Private Networks, power line communications, satellite communications and wireless communications (wireless sensor networks, WiMAX and wireless mesh networks) are described in detail. The motivation of this paper is to provide a better understanding of the hybrid network architecture that can provide heterogeneous electric system automation application requirements. In this regard, our aim is to present a structured framework for electric utilities who plan to utilize new communication technologies for automation and hence, to make the decision making process more effective and direct.This work was supported by NEETRAC under Project #04-157

The seamless integration of Web3D technologies with university curricula to engage the changing student cohort

The increasing tendency of many university students to study at least some courses at a distance limits their opportunities for the interactions fundamental to learning. Online learning can assist but relies heavily on text, which is limiting for some students. The popularity of computer games, especially among the younger students, and the emergence of networked games and game-like virtual worlds offers opportunities for enhanced interaction in educational applications. For virtual worlds to be widely adopted in higher education it is desirable to have approaches to design and development that are responsive to needs and limited in their resource requirements. Ideally it should be possible for academics without technical expertise to adapt virtual worlds to support their teaching needs. This project identified Web3D, a technology that is based on the X3D standards and which presents 3D virtual worlds within common web browsers, as an approach worth exploring for educational application. The broad goals of the project were to produce exemplars of Web3D for educational use, together with development tools and associated resources to support non-technical academic adopters, and to promote an Australian community of practice to support broader adoption of Web3D in education. During the first year of the project exemplar applications were developed and tested. The Web3D technology was found to be still in a relatively early stage of development in which the application of standards did not ensure reliable operation in different environments. Moreover, ab initio development of virtual worlds and associated tools proved to be more demanding of resources than anticipated and was judged unlikely in the near future to result in systems that non-technical academics could use with confidence. In the second year the emphasis moved to assisting academics to plan and implement teaching in existing virtual worlds that provided relatively easy to use tools for customizing an environment. A project officer worked with participating academics to support the teaching of significant elements of courses within Second LifeTM. This approach was more successful in producing examples of good practice that could be shared with and emulated by other academics. Trials were also conducted with ExitRealityTM, a new Australian technology that presents virtual worlds in a web browser. Critical factors in the success of the project included providing secure access to networked computers with the necessary capability; negotiating the complexity of working across education, design of virtual worlds, and technical requirements; and supporting participants with professional development in the technology and appropriate pedagogy for the new environments. Major challenges encountered included working with experimental technologies that are evolving rapidly and deploying new networked applications on secure university networks. The project has prepared the way for future expansion in the use of virtual worlds for teaching at USQ and has contributed to the emergence of a national network of tertiary educators interested in the educational applications of virtual worlds

The EnTrak system : supporting energy action planning via the Internet

Recent energy policy is designed to foster better energy efficiency and assist with the deployment of clean energy systems, especially those derived from renewable energy sources. To attain the envisaged targets will require action at all levels and effective collaboration between disparate groups (e.g. policy makers, developers, local authorities, energy managers, building designers, consumers etc) impacting on energy and environment. To support such actions and collaborations, an Internet-enabled energy information system called 'EnTrak' was developed. The aim was to provide decision-makers with information on energy demands, supplies and impacts by sector, time, fuel type and so on, in support of energy action plan formulation and enactment. This paper describes the system structure and capabilities of the EnTrak system

Digital technology and governance in transition: The case of the British Library

Comment on the organizational consequences of the new information and communications technologies (ICTs) is pervaded by a powerful imagery of disaggregation and a tendency for ?virtual? forms of production to be seen as synonymous with the ?end? of bureaucracy. This paper questions the underlying assumptions of the ?virtual organization?, highlighting the historically enduring, diversified character of the bureaucratic form. The paper then presents case study findings on the web-based access to information resources now being provided by the British Library (BL). The case study evidence produces two main findings. First, radically decentralised virtual forms of service delivery are heavily dependent on new forms of capacity-building and information aggregation. Second, digital technology is embedded in an inherently contested and contradictory context of institutional change. Current developments in the management and control of digital rights are consistent with the commodification of the public sphere. However, the evidence also suggests that scholarly access to information resources is being significantly influenced by the ?information society? objectives of the BL and other institutional players within the network of UK research libraries

The antecedents of e-learning adoption within Italian corporate universities: A comparative case study

The implementation of Information and Communication Technologies (ICT) in business education appears to be influenced by a number of organizational issues, such as culture and technological sophistication. However, extant research has had very little to say about the antecedents that shape the adoption and diffusion of ICT across companies. In order to shed light on the phenomenon under investigation, this paper presents a comparative case study between five Italian companies that have instituted a corporate university. By distinguishing companies in typical cases and deviant cases with regard to the extensive use of e-learning technologies, our findings provide some useful insights about the antecedents that make companies more or less prone to employ the new frontiers of technology in their CUs

Secure Integration of Desktop Grids and Compute Clusters Based on Virtualization and Meta-Scheduling

Reducing the cost for business or scientific computations, is a commonly expressed goal in today’s companies. Using the available computers of local employees or the outsourcing of such computations are two obvious solutions to save money for additional hardware. Both possibilities exhibit security related disadvantages, since the deployed software and data can be copied or tampered if appropriate countermeasures are not taken. In this paper, an approach is presented to let a local desktop machines and remote cluster resources be securely combined into a singel Grid environment. Solutions to several problems in the areas of secure virtual networks, meta-scheduling and accessing cluster schedulers from desktop Grids are proposed

Asynchronously Replicated Shared Workspaces for a Multi-Media Annotation Service over Internet

This paper describes a world wide collaboration system through multimedia Post-its (user generated annotations). DIANE is a service to create multimedia annotations to every application output on the computer, as well as to existing multimedia annotations. Users collaborate by registering multimedia documents and user generated annotation in shared workspaces. However, DIANE only allows effective participation in a shared workspace over a high performance network (ATM, fast Ethernet) since it deals with large multimedia object. When only slow or unreliable connections are available between a DIANE terminal and server, useful work becomes impossible. To overcome these restrictions we need to replicate DIANE servers so that users do not suffer degradation in the quality of service. We use the asynchronous replication service ODIN to replicate the shared workspaces to every interested site in a transparent way to users. ODIN provides a cost-effective object replication by building a dynamic virtual network over Internet. The topology of this virtual network optimizes the use of network resources while it satisfies the changing requirements of the users

Profiles of social networking sites users in the Netherlands

Online social networking has become a reality and integral part of the daily personal, social and business life. The extraordinary increase of the user numbers of Social Networking Sites (SNS) and the rampant creation of online communities presents businesses with many challenges and opportunities. From the commercial perspective, the SNS are an interesting and promising field: online social networks are important sources of market intelligence and also offer interesting options for co-operation, networking and marketing. For SMEs especially the Social Networking Sites represent a simple and low cost solution for listening the customer’s voice, reaching potential customers and creating extensive business networks. This paper presents the results of a national survey mapping the demographic, social and behavioral characteristics of the Dutch users of SNS. The study identifies four different user profiles and proposes a segmentation framework as basis for better understanding the nature and behavior of the participants in online communities. The findings present new insights to marketing strategists eager to use the communication potential of such communities; the findings are also interesting for businesses willing to explore the potential of online networking as a low cost yet very efficient alternative to physical, traditional networking

An integrated approach for analysing and assessing the performance of virtual learning groups

Collaborative distance learning involves a variety of elements and factors that have to be considered and measured in order to analyse and assess group and individual performance more effectively and objectively. This paper presents an approach that integrates qualitative, social network analysis (SNA) and quantitative techniques for evaluating online collaborative learning interactions. Integration of various different data sources, tools and techniques provides a more complete and robust framework for group modelling and guarantees a more efficient evaluation of group effectiveness and individual competence. Our research relies on the analysis of a real, long-term, complex collaborative experience, which is initially evaluated in terms of principled criteria and a basic qualitative process. At the end of the experience, the coded student interactions are further analysed through the SNA technique to assess participatory aspects, identify the most effective groups and the most prominent actors. Finally, the approach is contrasted and completed through a statistical technique which sheds more light on the results obtained that far. The proposal draws a well-founded line toward the development of a principled framework for the monitoring and analysis of group interaction and group scaffolding which can be considered a major issue towards the actual application of the CSCL proposals to real classrooms.Peer ReviewedPostprint (author's final draft