63 research outputs found

    Smart metering infrastructure for distribution network operation

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    With the increasing demand for energy throughout the world and the associated environmental problems, the development of a highly efficient and environmentally friendly Smart Grid has become an important objective worldwide. In Great Britain, the Smart Grid has been primarily focused on the distribution networks and smart metering is widely considered as a critical step towards the Smart Grid future. Conventionally, the communications infrastructure at the distribution level is very limited in terms of functionality and availability. There was very limited work to evaluate the impact of the communications performance of smart metering infrastructure on distribution network operation. This research investigated the impact of smart metering applications on communications requirements and the impact of the communications performance of smart metering infrastructure on distribution network operation. A smart metering communications infrastructure was modelled and simulated using OPNET. The impact of smart metering applications on smart metering communications requirements has been investigated. It is shown that individual communications requirements for smart meters are not particularly communications intensive and that infrequent large transactions posed the most significant challenges on the communications infrastructure. As the link speed decreased, large time delays were observed which have direct impact on the functions related to distribution network operations. An evaluation method was then developed to quantify the impact of smart metering communications infrastructure on distribution network operation. The main characteristics of the smart metering communications infrastructure were modelled. The characteristics of load variation were analysed and used to quantify the relationship between the time delay and the measurement error of the power system. The measured data from smart meters was refined to be used by the distribution network operational functions using state estimation and the impact was quantified using optimal power flow. Results show that fast data access is necessary for smart meter data to be used by the voltage control and the power control functions of a distribution network. The potential of using smart metering for outage management was investigated. A topology analysis method was developed which maps the physical plant model of a distribution network to a simplified analytical model. An outage area identification algorithm was developed which uses the information from smart meters and is based on the simplified network model. The outage area identification can act as one of the main functions of an outage management system providing possible outage extent information. The impact of smart meter communications on the outage area identification algorithm was investigated based on the OPNET communications model. Test results showed that smart metering has a potential to support outage management of a power distribution network. Test results showed that the arrival criterion and the smart metering communications infrastructure have a large impact on the performance of the outage area identification

    Communication in microgrids and virtual power plants

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    One of the cornerstones of the steady operation of microgrids and virtual power plants as building blocks for smart grid is the communication system, which is the main objective for evaluation and research in this thesis. The given project investigates the most widespread communication protocols along with IEC 61850 standard for substations automation applied in smart grids. Based on the presented analysis for communication technologies and protocols the appropriate communication solution for the laboratory microgrid at UiT – The Arctic University of Norway (Campus Narvik) is suggested and implemente

    The role of communication systems in smart grids: Architectures, technical solutions and research challenges

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    The purpose of this survey is to present a critical overview of smart grid concepts, with a special focus on the role that communication, networking and middleware technologies will have in the transformation of existing electric power systems into smart grids. First of all we elaborate on the key technological, economical and societal drivers for the development of smart grids. By adopting a data-centric perspective we present a conceptual model of communication systems for smart grids, and we identify functional components, technologies, network topologies and communication services that are needed to support smart grid communications. Then, we introduce the fundamental research challenges in this field including communication reliability and timeliness, QoS support, data management services, and autonomic behaviors. Finally, we discuss the main solutions proposed in the literature for each of them, and we identify possible future research directions

    New Challenges in Quality of Services Control Architectures in Next Generation Networks

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    A mesura que Internet i les xarxes IP s'han anat integrant dins la societat i les corporacions, han anat creixent les expectatives de nous serveis convergents així com les expectatives de qualitat en les comunicacions. Les Next Generation Networks (NGN) donen resposta a les noves necessitats i representen el nou paradigma d'Internet a partir de la convergència IP. Un dels aspectes menys desenvolupats de les NGN és el control de la Qualitat del Servei (QoS), especialment crític en les comunicacions multimèdia a través de xarxes heterogènies i/o de diferents operadors. A més a més, les NGN incorporen nativament el protocol IPv6 que, malgrat les deficiències i esgotament d'adreces IPv4, encara no ha tingut l'impuls definitiu.Aquesta tesi està enfocada des d'un punt de vista pràctic. Així doncs, per tal de poder fer recerca sobre xarxes de proves (o testbeds) que suportin IPv6 amb garanties de funcionament, es fa un estudi en profunditat del protocol IPv6, del seu grau d'implementació i dels tests de conformància i interoperabilitat existents que avaluen la qualitat d'aquestes implementacions. A continuació s'avalua la qualitat de cinc sistemes operatius que suporten IPv6 mitjançant un test de conformància i s'implementa el testbed IPv6 bàsic, a partir del qual es farà la recerca, amb la implementació que ofereix més garanties.El QoS Broker és l'aportació principal d'aquesta tesi: un marc integrat que inclou un sistema automatitzat per gestionar el control de la QoS a través de sistemes multi-domini/multi-operador seguint les recomanacions de les NGN. El sistema automatitza els mecanismes associats a la configuració de la QoS dins d'un mateix domini (sistema autònom) mitjançant la gestió basada en polítiques de QoS i automatitza la negociació dinàmica de QoS entre QoS Brokers de diferents dominis, de forma que permet garantir QoS extrem-extrem sense fissures. Aquesta arquitectura es valida sobre un testbed de proves multi-domini que utilitza el mecanisme DiffServ de QoS i suporta IPv6.L'arquitectura definida en les NGN permet gestionar la QoS tant a nivell 3 (IP) com a nivell 2 (Ethernet, WiFi, etc.) de forma que permet gestionar també xarxes PLC. Aquesta tesi proposa una aproximació teòrica per aplicar aquesta arquitectura de control, mitjançant un QoS Broker, a les noves xarxes PLC que s'estan acabant d'estandarditzar, i discuteix les possibilitats d'aplicació sobre les futures xarxes de comunicació de les Smart Grids.Finalment, s'integra en el QoS Broker un mòdul per gestionar l'enginyeria del tràfic optimitzant els dominis mitjançant tècniques de intel·ligència artificial. La validació en simulacions i sobre un testbed amb routers Cisco demostra que els algorismes genètics híbrids són una opció eficaç en aquest camp.En general, les observacions i avenços assolits en aquesta tesi contribueixen a augmentar la comprensió del funcionament de la QoS en les NGN i a preparar aquests sistemes per afrontar problemes del món real de gran complexitat.A medida que Internet y las redes IP se han ido integrando dentro de la sociedad y las corporaciones, han ido creciendo las expectativas de nuevos servicios convergentes así como las expectativas de calidad en las comunicaciones. Las Next Generation Networks (NGN) dan respuesta a las nuevas necesidades y representan el nuevo paradigma de Internet a partir de la convergencia IP. Uno de los aspectos menos desarrollados de las NGN es el control de la Calidad del Servicio (QoS), especialmente crítico en las comunicaciones multimedia a través de redes heterogéneas y/o de diferentes operadores. Además, las NGN incorporan nativamente el protocolo IPv6 que, a pesar de las deficiencias y agotamiento de direcciones IPv4, aún no ha tenido el impulso definitivo.Esta tesis está enfocada desde un punto de vista práctico. Así pues, con tal de poder hacer investigación sobre redes de prueba (o testbeds) que suporten IPv6 con garantías de funcionamiento, se hace un estudio en profundidad del protocolo IPv6, de su grado de implementación y de los tests de conformancia e interoperabilidad existentes que evalúan la calidad de estas implementaciones. A continuación se evalua la calidad de cinco sistemas operativos que soportan IPv6 mediante un test de conformancia y se implementa el testbed IPv6 básico, a partir del cual se realizará la investigación, con la implementación que ofrece más garantías.El QoS Broker es la aportación principal de esta tesis: un marco integrado que incluye un sistema automatitzado para gestionar el control de la QoS a través de sistemas multi-dominio/multi-operador siguiendo las recomendaciones de las NGN. El sistema automatiza los mecanismos asociados a la configuración de la QoS dentro de un mismo dominio (sistema autónomo) mediante la gestión basada en políticas de QoS y automatiza la negociación dinámica de QoS entre QoS brokers de diferentes dominios, de forma que permite garantizar QoS extremo-extremo sin fisuras. Esta arquitectura se valida sobre un testbed de pruebas multi-dominio que utiliza el mecanismo DiffServ de QoS y soporta IPv6. La arquitectura definida en las NGN permite gestionar la QoS tanto a nivel 3 (IP) o como a nivel 2 (Ethernet, WiFi, etc.) de forma que permite gestionar también redes PLC. Esta tesis propone una aproximación teórica para aplicar esta arquitectura de control, mediante un QoS Broker, a las noves redes PLC que se están acabando de estandardizar, y discute las posibilidades de aplicación sobre las futuras redes de comunicación de las Smart Grids.Finalmente, se integra en el QoS Broker un módulo para gestionar la ingeniería del tráfico optimizando los dominios mediante técnicas de inteligencia artificial. La validación en simulaciones y sobre un testbed con routers Cisco demuestra que los algoritmos genéticos híbridos son una opción eficaz en este campo.En general, las observaciones y avances i avances alcanzados en esta tesis contribuyen a augmentar la comprensión del funcionamiento de la QoS en las NGN y en preparar estos sistemas para afrontar problemas del mundo real de gran complejidad.The steady growth of Internet along with the IP networks and their integration into society and corporations has brought with it increased expectations of new converged services as well as greater demands on quality in communications. The Next Generation Networks (NGNs) respond to these new needs and represent the new Internet paradigm from the IP convergence. One of the least developed aspects in the NGNs is the Quality of Service (QoS) control, which is especially critical in the multimedia communication through heterogeneous networks and/or different operators. Furthermore, the NGNs natively incorporate the IPv6 protocol which, despite its shortcomings and the depletion of IPv4 addresses has not been boosted yet.This thesis has been developed with a practical focus. Therefore, with the aim of carrying out research over testbeds supporting the IPv6 with performance guarantees, an in-depth study of the IPv6 protocol development has been conducted and its degree of implementation and the existing conformance and interoperability tests that evaluate these implementations have been studied. Next, the quality of five implementations has been evaluated through a conformance test and the basic IPv6 testbed has been implemented, from which the research will be carried out. The QoS Broker is the main contribution to this thesis: an integrated framework including an automated system for QoS control management through multi-domain/multi-operator systems according to NGN recommendations. The system automates the mechanisms associated to the QoS configuration inside the same domain (autonomous system) through policy-based management and automates the QoS dynamic negotiation between peer QoS Brokers belonging to different domains, so it allows the guarantee of seamless end-to-end QoS. This architecture is validated over a multi-domain testbed which uses the QoS DiffServ mechanism and supports IPv6.The architecture defined in the NGN allows QoS management at level 3 (IP) as well as at level 2 (e.g. Ethernet, WiFi) so it also facilitates the management of PLC networks. Through the use of a QoS Broker, this thesis proposes a theoretical approach for applying this control architecture to the newly standardized PLC networks, and discusses the possibilities of applying it over the future communication networks of the Smart Grids.Finally, a module for managing traffic engineering which optimizes the network domains through artificial intelligence techniques is integrated in the QoS Broker. The validations by simulations and over a Cisco router testbed demonstrate that hybrid genetic algorithms are an effective option in this area.Overall, the advances and key insights provided in this thesis help advance our understanding of QoS functioning in the NGNs and prepare these systems to face increasingly complex problems, which abound in current industrial and scientific applications

    CORRUPTION IN THE PALESTINIAN AUTHORITY: NEO-PATRIMONIALISM, THE PEACE PROCESS AND THE ABSENCE OF STATE-HOOD

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    ABSTRACT The thesis examines the practice of corruption in the Palestinian Authority (PA) from the period of its establishment until the death of Arafat. Palestinian elite formation from the late Ottoman period until the establishment of the PA was assessed in order to identify the elites that came into power in the PA and the political cultures they came to espouse. The two primary elite groups’ (Outsider elites and Insider counter-elites) conflicting political cultures were assessed in how they influenced the decision making process, the construction, and exhibited institutional behaviour of the PA. With the signing of the Declaration of Principles on Interim Self-Government Arrangements (Oslo Accords) on the 13th of September, 1993 between the Palestine Liberation Organisation (PLO) and the Government of Israel it established the Palestinian Authority as the government in transition for the Palestinians. The agreements conferred the governing power and leadership role to the PLO Outsider elites (under Arafat). Due to the secret nature and asymmetrical power relation by which the negotiations and agreements were conducted and signed between the PLO Outsider leadership and the Government of Israel, which excluded inputs from Palestinian Insider elites, the culminating PA structure came to exhibit institutional weakness with certain neo-patrimonial behaviour. The political framework by which the Oslo Accords constructed the PA and influenced by international actors warranted institutional-weakness. Moreover, as external actors’ demands for the PA to deal with the declining Peace Process, and address political and security issues increased, PA corruption behaviour became more apparent and proliferated which became indicative of its fundamental problem in that it lacked statehood, lacked authority and legitimacy, and thus resorted to neo-patrimonial and repressive methods to govern. This neo-patrimonial political culture of Arafat and his governing Outsider elites used corruption as a PA political tool for survival thus suppressing a nascent democratic political culture of the Insiders and consequently led to an institutionalisation of corruption in the PA

    Applications integration for manufacturing control systems with particular reference to software interoperability issues

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    The introduction and adoption of contemporary computer aided manufacturing control systems (MCS) can help rationalise and improve the productivity of manufacturing related activities. Such activities include product design, process planning and production management with CAD, CAPP and CAPM. However, they tend to be domain specific and would generally have been designed as stand-alone systems where there is a serious lack of consideration for integration requirements with other manufacturing activities outside the area of immediate concern. As a result, "islands of computerisation" exist which exhibit deficiencies and constraints that inhibit or complicate subsequent interoperation among typical MCS components. As a result of these interoperability constraints, contemporary forms of MCS typically yield sub-optimal benefits and do not promote synergy on an enterprise-wide basis. The move towards more integrated manufacturing systems, which requires advances in software interoperability, is becoming a strategic issue. Here the primary aim is to realise greater functional synergy between software components which span engineering, production and management activities and systems. Hence information of global interest needs to be shared across conventional functional boundaries between enterprise functions. The main thrust of this research study is to derive a new generation of MCS in which software components can "functionally interact" and share common information through accessing distributed data repositories in an efficient, highly flexible and standardised manner. It addresses problems of information fragmentation and the lack of formalism, as well as issues relating to flexibly structuring interactions between threads of functionality embedded within the various components. The emphasis is on the: • definition of generic information models which underpin the sharing of common data among production planning, product design, finite capacity scheduling and cell control systems. • development of an effective framework to manage functional interaction between MCS components, thereby coordinating their combined activities. • "soft" or flexible integration of the MCS activities over an integrating infrastructure in order to (i) help simplify typical integration problems found when using contemporary interconnection methods for applications integration; and (ii) enable their reconfiguration and incremental development. In order to facilitate adaptability in response to changing needs, these systems must also be engineered to enable reconfigurability over their life cycle. Thus within the scope of this research study a new methodology and software toolset have been developed to formally structure and support implementation, run-time and change processes. The tool set combines the use of IDEFO (for activity based or functional modelling), IDEFIX (for entity-attribute relationship modelling), and EXPRESS (for information modelling). This research includes a pragmatic but effective means of dealing with legacyl software, which often may be a vital source of readily available information which supports the operation of the manufacturing enterprise. The pragmatism and medium term relevance of the research study has promoted particular interest and collaboration from software manufacturers and industrial practitioners. Proof of concept studies have been carried out to implement and evaluate the developed mechanisms and software toolset

    Political identity building and the Israeli-Palestinian conflict : theoretical approach and empirical analysis

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    This thesis develops a general theoretical approach to political identity building under emerging conditions of globalisation. This theoretical approach is used to analyse political developments in Israeli and Palestinian societies since the start of the Oslo process in 1993. Combining Rosenau's concepts of 'frontiers' and 'fragmegration' with Wendt's analysis of identity in international relations, a three level model for political identity building is developed. It argues that political identity is formed on the substate, state and the supra-state level. Although the state level is maintained as an important location for political identity, it is argued that the concept of 'national identity' is too limited a variable under emerging conditions of globalisation. Six main significators of political identity are analysed: territory, ethnicity, history, language, religion and gender. These cut across all three levels. The case studies use a series of in-depth interviews with political actors on all three levels. It is shown that both societies are currently experiencing a deep identity crisis. Different political identity groups have developed which lack common ground in their conceptions of what kind of states Israel or Palestine should be. Israeli society is increasingly fragmenting on all three levels of political interaction. In consequence, the state level is turning into a battleground for particular political identities and is increasingly unable to establish societal cohesion. Palestinian society experiences an increasing isolation of the state level. This is due to the autocratic and neo- patrimonial structure of the Palestinian Authority which marginalised the substate and the supra-state level from political decision making. Therefore, here too, societal cohesion cannot be generated on the state level. In consequence, opposition to the Palestinian Authority and the peace process in general is strengthened

    Software framework for the development of context-aware reconfigurable systems

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    In this project we propose a new software framework for the development of context-aware and secure controlling software of distributed reconfigurable systems. Context-awareness is a key feature allowing the adaptation of systems behaviour according to the changing environment. We introduce a new definition of the term “context” for reconfigurable systems then we define a new context modelling and reasoning approach. Afterwards, we define a meta-model of context-aware reconfigurable applications that paves the way to the proposed framework. The proposed framework has a three-layer architecture: reconfiguration, context control, and services layer, where each layer has its well-defined role. We define also a new secure conversation protocol between distributed trustless parts based on the blockchain technology as well as the elliptic curve cryptography. To get better correctness and deployment guarantees of applications models in early development stages, we propose a new UML profile called GR-UML to add new semantics allowing the modelling of probabilistic scenarios running under memory and energy constraints, then we propose a methodology using transformations between the GR-UML, the GR-TNCES Petri nets formalism, and the IEC 61499 function blocks. A software tool implementing the methodology concepts is developed. To show the suitability of the mentioned contributions two case studies (baggage handling system and microgrids) are considered.In diesem Projekt schlagen wir ein Framework für die Entwicklung von kontextbewussten, sicheren Anwendungen von verteilten rekonfigurierbaren Systemen vor. Kontextbewusstheit ist eine Schlüsseleigenschaft, die die Anpassung des Systemverhaltens an die sich ändernde Umgebung ermöglicht. Wir führen eine Definition des Begriffs ``Kontext" für rekonfigurierbare Systeme ein und definieren dann einen Kontextmodellierungs- und Reasoning-Ansatz. Danach definieren wir ein Metamodell für kontextbewusste rekonfigurierbare Anwendungen, das den Weg zum vorgeschlagenen Framework ebnet. Das Framework hat eine dreischichtige Architektur: Rekonfigurations-, Kontextkontroll- und Dienste-Schicht, wobei jede Schicht ihre wohldefinierte Rolle hat. Wir definieren auch ein sicheres Konversationsprotokoll zwischen verteilten Teilen, das auf der Blockchain-Technologie sowie der elliptischen Kurven-Kryptographie basiert. Um bessere Korrektheits- und Einsatzgarantien für Anwendungsmodelle zu erhalten, schlagen wir ein UML-Profil namens GR-UML vor, um Semantik umzufassen, die die Modellierung probabilistischer Szenarien unter Speicher- und Energiebeschränkungen ermöglicht. Dann schlagen wir eine Methodik vor, die Transformationen zwischen GR-UML, dem GR-TNCES-Petrinetz-Formalismus und den IEC 61499-Funktionsblöcken verwendet. Es wird ein Software entwickelt, das die Konzepte der Methodik implementiert. Um die Eignung der genannten Beiträge zu zeigen, werden zwei Fallstudien betrachtet

    Washington's meddling for peace in the politics of Israel and the Palestinian Authority

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Political Science, 2012.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (p. 819-878).Governments often try to use their foreign policies to influence the choice of who will rule in other countries. However, scholars know strikingly little about this commonplace and consequential phenomenon, especially when it is scoped down to the use of diplomatic tools short of force. Indeed, this lacuna is especially striking in comparison to the voluminous literatures on other forms of international meddling such as military intervention or coercive diplomacy for producing policy change. This project seeks to contribute to the nascent research program on partisan intervention by drawing on the historical record to pose tentative answers to two pertinent research questions in the context of America's Mideast policies. The first topic focuses on occurrence: when are sender states likely to engage in this behavior, and when are they less likely to do so? The second topic focuses on efficacy: when does this policy help achieve the sender state's objectives, and when does it fail? This project seeks to answer these questions by drawing on Washington's peace process diplomacy. It uses official archives and expert interviews to supplement the existing historiographic record, documenting America's efforts to bolster perceived pro--peace leaders in Israel since 1977 and among the Palestinians since 1986. It also explores U.S. decision--making toward Iran as a shadow case for leverage over additional study variables, along with other instances of outside intervention into Israeli politics by European or Arab states. It finds that the issue area of leadership selection intervention is unusually subject to the individualistic preferences of top leaders in the sender state. Because exceptionally blatant meddling of this sort tends to elicit a backlash, self-admitted LSI is therefore discouraged. Instead, practitioners go to great lengths to maintain alternative pretenses that prevent revelation of their true intentions. This inherently complicates the task of legislative oversight, decreases points of leverage for lobbyists or working--level bureaucrats, and magnifies these leaders' subjective interpretation of international circumstances. In short, LSI is intensely personal.by David Andrew Weinberg.Ph.D
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