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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

A Novel Patient Monitoring Framework and Routing Protocols for Energy & QoS Aware Communication in Body Area Networks

Khan, Zahoor Ali 20 June 2013 (has links)
Significant challenges to patient monitoring systems in a hospital environment include the reliable and energy-efficient transmission of data and their real-time display. This thesis proposes innovative and novel mechanisms for the reliable transmission of patient data in Body Area Network (BAN) communication, which simultaneously ensure high throughput, low data latency, and low energy consumption by implementing energy and QoS aware routing protocols. Five main contributions are made in this regard. Firstly, a novel patient monitoring system (ZK-BAN peering framework) is proposed for real-time hospital BAN communication that displays patient data on the display units by considering data privacy, low energy consumption, better control on the devices, and patient mobility. Secondly, a novel energy-aware peering routing protocol (EPR) is introduced in which the choice of next hop is based on the residual energy and geographic information of the neighbor nodes. EPR contains three main components: a Hello protocol, a neighbor table constructor algorithm, and a routing table constructor algorithm. Thirdly, a new modular QoS-aware routing protocol (QPRD) is designed to handle the ordinary and delay-sensitive data for BAN communication in hospitals. QPRD provides an end-to-end path delay mechanism to calculate the path delays of all possible paths from a source to destination and then chooses the best path with the lowest path delay for delay-sensitive packets. Fourthly, a novel modular QoS-aware routing protocol (QPRR) is developed to handle ordinary and reliability-sensitive data for BAN communication in hospitals. The modular architecture of QPRR includes five modules: a reliability module, a packet classifier, a Hello protocol module, a routing services module, and a QoS-aware queuing module. The proposed mechanisms for end-to-end path reliability calculation and data transmission using redundant paths ensure more reliable BAN communication. Finally, a new integrated energy and QoS aware routing protocol (ZEQoS) is designed to deal with ordinary, delay-sensitive, and reliability-sensitive data packets. Extensive simulations in the OMNeT++ based Castalia 3.2 simulator show that EPR, QPRD, QPRR, and ZEQoS perform better than other similar energy and QoS aware routing protocols.
102

Towards a model for ensuring optimal interoperability between the security systems of trading partners in a business-to-business e-commerce context

Pather, Maree 25 August 2009 (has links)
A vast range of controls/countermeasures exists for implementing security on information systems connected to the Internet. For the practitioner attempting to implement an integrated solution between trading partners operating across the Internet, this has serious implications in respect of interoperability between the security systems of the trading partners. The problem is exacerbated by the range of specification options within each control. This research is an attempt to find a set of relevant controls and specifications towards a framework for ensuring optimal interoperability between trading partners in this context. Since a policy-based, layered approach is advocated, which allows each trading partner to address localized risks independently, no exhaustive risk analysis is attempted. The focus is on infrastructure that is simultaneously optimally secure and provides optimal interoperability. It should also be scalable, allowing for additional security controls to be added whenever deemed necessary. / Computing / M. Sc. (Information Systems)
103

A framework for promoting interoperability in a global electronic market-space

Pather, Maree 30 June 2005 (has links)
The primary contributions to the area of electronic business integration, propounded by this thesis, are (in no particular order):  A novel examination of global Business-to-Business (B2B) interoperability in terms of a "multiplicity paradox" and of a "global electronic market-space" from a Complex Systems Science perspective.  A framework for an, integrated, global electronic market-space, which is based on a hierarchical, incremental, minimalist-business-pattern approach. A Web Services-SOA forms the basis of application-to-application integration within the framework. The framework is founded in a comprehensive study of existing technologies, standards and models for secure interoperability and the SOA paradigm. The Complex Systems Science concepts of "predictable structure" and "structural complexity" are used consistently throughout the progressive formulation of the framework.  A model for a global message handler (including a standards-based message-format) which obviates the common problems implicit in standard SOAP-RPC. It is formulated around the "standardized, common, abstract application interface" critical success factor, deduced from examining existing models. The model can be used in any collaboration context.  An open standards-based security model for the global message handler. Conceptually, the framework comprises the following:  An interoperable standardized message format: a standardized SOAP-envelope with standardized attachments (8-bit binary MIME-serialized XOP packages).  An interoperable standardized message-delivery infrastructure encompassing an RPC-invoked message-handler - a Web service, operating in synchronous and/or asynchronous mode, which relays attachments to service endpoints.  A business information processing infrastructure comprised of: a standardized generic minimalist-business-pattern (simple buying/selling), comprising global pre-specifications for business processes (for example, placing an order), standardized specific atomic business activities (e.g. completing an order-form), a standardized document-set (including, e.g. an order-form) based on standardized metadata (common nomenclature and common semantics used in XSD's, e.g. the order-form), the standardized corresponding choreography for atomic activities (e.g. acknowledgement of receipt of order-form) and service endpoints (based on standardized programming interfaces and virtual methods with customized implementations). / Theoretical Computing / PHD (INFORMATION SYSTEMS)
104

Arquitetura e implementação de uma rede em anel de comutação optica de pacotes / Architecture and implementation of an optical packet switched ring network

Oliveira, Vinicius Garcia de 26 August 2009 (has links)
Orientadores: Peter Jurgen Tatsch, Marcos Rogerio Salvador / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-14T19:15:56Z (GMT). No. of bitstreams: 1 Oliveira_ViniciusGarciade_M.pdf: 16025820 bytes, checksum: 7d131f46cf420654c7f70129842770a7 (MD5) Previous issue date: 2009 / Resumo: A convergência das aplicações, dos serviços e das redes de telecomunicação está mudando o mundo e o jeito como as pessoas agem e interagem. Embora com limitações, computação distribuída, teleconferência, tele-educação rádio, televisão e jogos já são possíveis na Internet. É razoável propor que em um futuro próximo estas limitações tendam a desaparecer e será possível suportar aplicações bem mais sofisticadas e complexas, tais como realidade virtual e tele-presença. ...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital. / Abstract: The convergence of the services, applications and telecommunication networks is changing the way people do their things and interact to each other. With limitations, distributed computing, teleconference, tele-education, radio, television and games are already possible through the Internet. In a close future these limitations probably will disappear and it will be possible to provide new and more sophisticated applications as virtual reality and tele-presence....Note: The complete abstract is available with the full electronic document / Mestrado / Telecomunicações / Mestre em Engenharia Elétrica
105

PLEX MPLS : analise, projeto e implementação de uma plataforma para experimentos com MPLS com suporte a QoS / PLEX MPLS : analysis, project and implementation of a platform for experiments with MPLS with QoS support

Sazima, Ricardo 15 October 2005 (has links)
Orientador: Mauricio Ferreira Magalhães / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-04T17:32:51Z (GMT). No. of bitstreams: 1 Sazima_Ricardo_M.pdf: 1107563 bytes, checksum: a1179beaec699c0dcd87b45284e4a99c (MD5) Previous issue date: 2004 / Resumo: Dados a banda de transmissão atualmente disponível, o protocolo (IP) utilizado para transmitir a maior parte de tráfego e a quantidade de tráfego e seus requisitos de aos, a Engenharia de Tráfego (TE, de Traffic Engineering) tomou-se um componente cada vez mais importante nas redes de comunicações. O padrão do IETF para enncaminhamento roteamento entitulado Multi-Protocol Label Switching (MPLS) preenche lacunas importantes neste cenário e é peça chave das metodologias de TE mais sofisticadas. Nesta dissertação é apresentado um modelo genérico de TE e uma proposta para uma Plataforma para Experimentos com MPLS (PLEX MPLS) que permite que o usuário defina, execute, e analise configurações de Engenharia de Tráfego com MPLS em uma rede IP. Os principais objetivos da PLEX MPLS são: . Estudo da tecnologia MPLS e suporte a outros trabalhos em andamento no contexto do grupo de estudos em MPLS do DCA . Experimentos com engenharia de tráfego com MPLS: validação das tecnologias e conceitos relacionados . Experimentos didáticos em disciplinas de laboratório de redes. Os principais conceitos de TE e MPLS são apresentados como referência, bem como uma descrição do NIST Switch, a plataforma MPLS escolhida para este trabalho. A análise, projeto e implementação da PLEX MPLS são apresentados, pois formam parte significativa do trabalho desenvolvido. A PLEX não só utiliza, como também estende as funcionalidades oferecidas pelo NIST Switch a fim de oferecer um esquema de TE mais completo e eficiente. Na fase de análise, vemos quais os principais requisitos para a implementação desta plataforma, seguindo uma metodologia de Engenharia de Software. Na fase de projeto, vemos as soluções propostas para os problemas identificados na fase de análise e temos uma especificação dos componentes a serem implementados. Na fase seguinte, discutimos a implementação das principais características dos componentes da PLEX, justificando as decisões tomadas. Para validar a implementação da PLEX de acordo com sua proposta, foram realizados alguns experimentos em uma rede de testes com tráfego real. A execução destes experimentos é descrita e seus resultados analisados. Os resultados obtidos assinalam claramente a importância e utilidade de esquemas de TE baseada em MPLS. Uma interessante metodologia para TE, compilada a partir de várias propostas, é apresentada. Finalmente, apontam-se caminhos a seguir em um trabalho futuro de refinamento da PLEX / Abstract: Given the bandwidth currently available, the protocol (IP) used to transmit most Internet traffic, the quantity of traffic produced and its QoS requirements, Traffic Engineering (TE) has become an increasingly important component of communications networks. IETF's standard for forwarding/routing, which is entitled Multi-Protocol Label Switching (MPLS), presents important solutions in this scenario playing a major role in more sophisticated TE methodologies. This work presents a generic methodology for TE and a proposal for a Platform for Experiments with MPLS (PLEX MPLS) which allows the user to define, execute and analyze Traffic Engineering configurations with MPLS in an IP network. The main goals of PLEX MPLS are: . Study of the M PLS technology and support of other ongoing works with M PLS in the DCA . Traffic Engineering experiments with MPLS: validation of the related concepts and technologies . Support of didactic experiments in academic disciplines. The main concepts of MPLS and TE are presented as reference, as well as a brief description of NIST Switch, the MPLS software chosen for the PLEX MPLS implementation. The analysis, project and implementation of PLEX MPLS are presented, since are significant part of the developed work. PLEX not only uses, but also extends NIST Switch functionalities to offer a more complete and efficient TE scheme. In the analysis phase the main requirements for the PLEX implementation are specified, following a well-known Software Engineering methodology. The solutions found for the problems identified in the analysis phase are presented in the project phase alongside with a specification of the components that will be implemented. In the next phase, the implementation of PLEX is discussed focusing on the most important characteristics of PLEX components and justifying the implementation ecisions. In order to validate PLEX implementation and its proposal, some experiments were made in a test network with reallive traffic. These experiments are described and its results analyzed. The results obtained clearly indicate the importance and utility of TE schemes based on MPLS. Also an interesting TE methodology compiled from several proposals is presented. Finally, possible improvements and future work on PLEX MPLS are indicated. / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica
106

Deployment, Management, & Operations of Internet Routers for Space-Based Communication

Sims, Zack A. 25 August 2015 (has links)
No description available.
107

Modelagem do prognóstico e gestão da saúde de máquinas mecânicas no contexto de sistemas ciberfísicos na manufatura / Prognostics and health management modelling of mechanical machines in the context of cyber-physical systems in mnufacturing

Nunez, David Lira 14 September 2017 (has links)
Os recentes avanços na manufatura inteligente abrem oportunidades na área do suporte industrial, especificamente na manutenção e gestão de ativos físicos. Essa tendência permite que os dados coletados das máquinas, quando estão em pleno funcionamento, possam interagir com computadores, (ciberespaço), através de uma rede de comunicação formando assim o conceito de Sistemas Ciberfísicos (CPS – do inglês Cyber-Physical Systems). Além disso, os rápidos avanços da tecnologia de informação e comunicação proporcionam ferramentas para que essa interação possa analisar os dados, de forma cada vez mais rápida, autônoma, ubíqua e em tempo real, oferecendo informações que auxiliam aos humanos na tomada de decisões mais eficazes. Nesse contexto, o Prognóstico e Gestão da Saúde de máquinas (PHM – do inglês Prognostics Health and Management) é indicado como uma aplicação promissora da manufatura inteligente dentro do contexto de CPS. Atualmente as propostas de PHM encontradas na literatura cientifica são aplicadas a casos específicos e sem uma padronização da sua implementação, impedindo que tais abordagens possam ser replicadas em diferentes cenários da manufatura. Assim, o presente trabalho propõe a construção de um modelo ontológico para auxiliar na implementação do PHM em diversos cenários de manufatura, a ser aproveitada futuramente por ferramentas de softwares com foco em manufatura inteligente, padronizando seus conceitos, termos, e a forma de coleta e tratamento de dados. A abordagem metodológica DSR (do inglês Design Science Research) é usada para guiar o desenvolvimento da pesquisa. A construção deste modelo ontológico, que integra tanto os dados coletados quanto as informações necessárias para a tomada de decisões, possibilita o controle da estimativa de uma falha antes dela ocorrer de uma forma mais autônoma. Os principais resultados do modelo ontológico construído são: uma ontologia flexível capaz de ser usada em vários tipos de máquinas mecânicas de diversos tipos de manufatura; a possibilidade de armazenar o conhecimento contido em normas internacionais, históricos de atividades das máquinas, e arquiteturas consolidadas no contexto do PHM, permitindo a constante atualização de dados dependendo de particularidades que cada processo produtivo pode conter, e finalmente, usando a linguagem SPARQL entrega-se informações que podem ser usadas para tomada de decisões em intervenções oportunas de manutenção nos equipamentos de uma indústria real. O modelo é demonstrado considerando o caso de uma bomba centrífuga que comprovou sua fidelidade, integridade, nível de detalhe, robustez e consistência, fornecendo informações anteriormente alimentadas por dados reais obtidos em empresas próximas. / Recent advances in smart manufacturing open up opportunities in industrial support, specifically in maintenance and physical asset management. This trend allows data collected from machines, when are in full operation, to interact with cyberspace computers through a communication network, thus forming the concept of cyber-physical systems (CPS). Besides, rapid advances in information and communications technologies provide tools for analysing data, in an increasingly rapid, autonomously, ubiquitous and in real time way, providing information that assists humans in making better decisions. In this sense, Prognostics and Health Management (PHM) of machines, is indicated as a promising application of Smart Manufacturing in the CPS contexto. Currently the PHM proposals found in the scientific literature are applied to specific cases and without a standardization of their implementation, preventing such approaches from being replicated in different manufacturing scenarios. Thus, the present work proposes the construction of an ontological model to assist in the implementation of the PHM in several manufacturing scenarios, to be harnessed in the future by software tools focused on intelligent manufacturing, standardizing their concepts, terms, and the form of data collection and processing. The DSR (Design Science Research) methodological approach is used to guide the development of the research. The construction of this ontological model, which integrates both the collected data and the necessary information for the decision making, allows the control of the estimate of a failure before it occurs in a more autonomous way. The main results of the ontological model are: a flexible ontology capable of being used on several types of mechanical machines of various types of manufacturing; the possibility of storing the knowledge contained in international standards, machine history of activities, and consolidated architectures in the context of the PHM, allows the constant updating of data depending on particularities that each productive process can contain, and finally, using the SPARQL language, it is given information that can be used for decisionmaking in timely maintenance interventions in the equipment of a real industry. The model is demonstrated considering the case of a centrifugal pump that proved its fidelity, integrity, level of detail, robustness and consistency, providing information previously fed by real data obtained in nearby companies.
108

Modelagem do prognóstico e gestão da saúde de máquinas mecânicas no contexto de sistemas ciberfísicos na manufatura / Prognostics and health management modelling of mechanical machines in the context of cyber-physical systems in mnufacturing

Nunez, David Lira 14 September 2017 (has links)
Os recentes avanços na manufatura inteligente abrem oportunidades na área do suporte industrial, especificamente na manutenção e gestão de ativos físicos. Essa tendência permite que os dados coletados das máquinas, quando estão em pleno funcionamento, possam interagir com computadores, (ciberespaço), através de uma rede de comunicação formando assim o conceito de Sistemas Ciberfísicos (CPS – do inglês Cyber-Physical Systems). Além disso, os rápidos avanços da tecnologia de informação e comunicação proporcionam ferramentas para que essa interação possa analisar os dados, de forma cada vez mais rápida, autônoma, ubíqua e em tempo real, oferecendo informações que auxiliam aos humanos na tomada de decisões mais eficazes. Nesse contexto, o Prognóstico e Gestão da Saúde de máquinas (PHM – do inglês Prognostics Health and Management) é indicado como uma aplicação promissora da manufatura inteligente dentro do contexto de CPS. Atualmente as propostas de PHM encontradas na literatura cientifica são aplicadas a casos específicos e sem uma padronização da sua implementação, impedindo que tais abordagens possam ser replicadas em diferentes cenários da manufatura. Assim, o presente trabalho propõe a construção de um modelo ontológico para auxiliar na implementação do PHM em diversos cenários de manufatura, a ser aproveitada futuramente por ferramentas de softwares com foco em manufatura inteligente, padronizando seus conceitos, termos, e a forma de coleta e tratamento de dados. A abordagem metodológica DSR (do inglês Design Science Research) é usada para guiar o desenvolvimento da pesquisa. A construção deste modelo ontológico, que integra tanto os dados coletados quanto as informações necessárias para a tomada de decisões, possibilita o controle da estimativa de uma falha antes dela ocorrer de uma forma mais autônoma. Os principais resultados do modelo ontológico construído são: uma ontologia flexível capaz de ser usada em vários tipos de máquinas mecânicas de diversos tipos de manufatura; a possibilidade de armazenar o conhecimento contido em normas internacionais, históricos de atividades das máquinas, e arquiteturas consolidadas no contexto do PHM, permitindo a constante atualização de dados dependendo de particularidades que cada processo produtivo pode conter, e finalmente, usando a linguagem SPARQL entrega-se informações que podem ser usadas para tomada de decisões em intervenções oportunas de manutenção nos equipamentos de uma indústria real. O modelo é demonstrado considerando o caso de uma bomba centrífuga que comprovou sua fidelidade, integridade, nível de detalhe, robustez e consistência, fornecendo informações anteriormente alimentadas por dados reais obtidos em empresas próximas. / Recent advances in smart manufacturing open up opportunities in industrial support, specifically in maintenance and physical asset management. This trend allows data collected from machines, when are in full operation, to interact with cyberspace computers through a communication network, thus forming the concept of cyber-physical systems (CPS). Besides, rapid advances in information and communications technologies provide tools for analysing data, in an increasingly rapid, autonomously, ubiquitous and in real time way, providing information that assists humans in making better decisions. In this sense, Prognostics and Health Management (PHM) of machines, is indicated as a promising application of Smart Manufacturing in the CPS contexto. Currently the PHM proposals found in the scientific literature are applied to specific cases and without a standardization of their implementation, preventing such approaches from being replicated in different manufacturing scenarios. Thus, the present work proposes the construction of an ontological model to assist in the implementation of the PHM in several manufacturing scenarios, to be harnessed in the future by software tools focused on intelligent manufacturing, standardizing their concepts, terms, and the form of data collection and processing. The DSR (Design Science Research) methodological approach is used to guide the development of the research. The construction of this ontological model, which integrates both the collected data and the necessary information for the decision making, allows the control of the estimate of a failure before it occurs in a more autonomous way. The main results of the ontological model are: a flexible ontology capable of being used on several types of mechanical machines of various types of manufacturing; the possibility of storing the knowledge contained in international standards, machine history of activities, and consolidated architectures in the context of the PHM, allows the constant updating of data depending on particularities that each productive process can contain, and finally, using the SPARQL language, it is given information that can be used for decisionmaking in timely maintenance interventions in the equipment of a real industry. The model is demonstrated considering the case of a centrifugal pump that proved its fidelity, integrity, level of detail, robustness and consistency, providing information previously fed by real data obtained in nearby companies.
109

OpenFlow based load balancing and proposed theory for integration in VoIP network

Pandita, Shreya 21 May 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In today's internet world with such a high traffic, it becomes inevitable to have multiple servers representing a single logical server to share enormous load. A very common network configuration consists of multiple servers behind a load balancer. The load balancer determines which server would service a clients request or incoming load from the client. Such a hardware is expensive, runs a fixed policy or algorithm and is a single point of failure. In this paper, we will implement and analyze an alternative load balancing architecture using OpenFlow. This architecture acquires flexibility in policy, costs less and has the potential to be more robust. This paper also discusses potential usage of OpenFlow based load balancing for media gateway selection in SIP-PSTN networks to improve VoIP performance.
110

Reducing handoff latency in proxy mobile IPv6

Vojini, Sumith Dev 21 May 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Mobile IP though allows mobility features to a node it suffers from signaling Latencies which are mainly incurred due to the fact that the MN itself is involved in the handover process. To overcome this problem proxy mobile IPv6(PMIPv6) was defined where the mobility signaling is taken care of by a proxy server while keeping track of the MN's movement. PMIPv6 has considerably reduced the handover latency but the demand for real time applications over the network has increased tremendously due to recent explosion of the cloud era. My thesis focuses on increasing the L3 handoff signaling efficiency by reducing the latency. This is achieved by our idea to do both the AAA authentication as well as the LMA registration in PMIPv6 at the same time. The simulation results show that our proposed approach perform better than the current PMIPv6 L3 handover signaling reducing the latency as well as packet loss.

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