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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.
51

Vývoj aplikací na platformě Windows Mobile / Mobile application development on Windows Mobile platform

Novotný, Marek January 2009 (has links)
This thesis treats of the development of mobile applications for Windows Mobile platform. It contains a list of other mobile platforms (mobile operating systems) and a comparative table according to selected categories, so that readers can get an idea of other platforms. Part of this thesis is an overview of technologies for development, which is supported by the comparative table. The main objective is to propose a methodology of mobile application development for platform Windows Mobile. To clarify the most important specifics serves the separate chapters describing these specifics. It is about the design of user interface for mobile applications, where attention is placed on the method of operating, because for each method of operating should be a different user interface design. Another specific feature, which is discussed in my thesis, is testing applications in Microsoft Device Emulator V3, this precedes the description of this tool for testing and the possibilities of its settings. To demonstrate the methodology the thesis contains the practical example illustrating the gradual steps corresponding to the phases of the methodology and execution of activities. In the annex are tables describing the various phases of the methodology, a description of their objectives, roles and them associated activities and what are the inputs and outputs of this phase.
52

Design and implementation of architectures for the deployment of secure community wireless networks

Hortelano Otero, Jorge 25 February 2011 (has links)
Recientes avances en las tecnologías de la comunicación, así como la proliferación de nuevos dispositivos de computación, están plasmando nuestro entorno hacia un Internet ubicuo. Internet ofrece una plataforma global para acceder con bajo coste a una vasta gama de servicios de telecomunicaciones, como el correo electrónico, comercio electrónico, tele-educación, tele-salud y tele-medicina a bajo coste. Sin embargo, incluso en los países más desarrollados, un gran número de áreas rurales todavía están pobremente equipadas con una infraestructura básica de telecomunicaciones. Hoy en día, existen algunos esfuerzos para resolver esta falta de infraestructura, pero resultan todavía insuficientes. Con este objetivo presentamos en esta tesis RuralNet, una red comunitaria inalámbrica para proveer acceso a Internet de forma personalizada a los subscriptores de un área rural. Los objetivos de este estudio han sido el desarrollo de una nueva arquitectura para ofrecer un acceso a Internet flexible y seguro para zonas rurales aisladas. RuralNet combina el paradigma de las redes mesh y el uso de los dispositivos inalámbricos embebidos más económicos para ofrecer un gran número de servicios y aplicaciones basados en Internet. La solución desarrollada por RuralNet es capaz de cubrir grandes áreas a bajo coste, y puede también ser fácilmente desplegado y extendido tanto en términos de cobertura como de servicios ofrecidos. Dado que la implementación y la evaluación de RuralNet requiere un alto coste y una gran cantidad de mano de obra, hemos considerado que la simulación y la emulación eran una alternativa válida para ahorrar costes. Con este objetivo hemos desarrollado Castadiva, un emulador flexible proyectado para la evaluación de redes MANET y mesh. Castadiva es un emulador basado en dispositivos de bajo coste, utilizado para evaluar los protocolos y las aplicaciones desarrolladas. / Hortelano Otero, J. (2011). Design and implementation of architectures for the deployment of secure community wireless networks [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/10079 / Palancia
53

Emulátor přenosové sítě / Transmission network emulator

Urbanovský, Jozef January 2020 (has links)
Diplomová práca sa zaoberá vývojom emulátoru prenosových parametrov dátovych sietí nad protokolovou sadou TCP/IP. Práca opisuje špecifiká sieťovej časti Linuxového jadra ako aj realizáciu emulátoru pomocou userspace programov ako tc, netem, ifb a iptables ovládajúcich jadro. Program pre emuláciu je realizovaný v jazyku Python a je ovládaný cez grafické rozhranie vytvorené s PyQt5. Aplikácia bola otestovaná a verifikovaná, že je dostatočne presnou reprezentáciou špecifikovanej WAN siete a že taktiež využíva prostriedky efektívne.
54

Emulátor Mobilní telefonní ústředny / Mobile Switching Centre Emulator

Králíček, Jan January 2013 (has links)
This thesis attempts to provide basic overview of the topic of the GSM system and tries to design Mobile Switching Centre Emulator that could perform the operation Location Update. The first part of this thesis describes the principles and specifics of the GSM network (network structure, the operations required to support user mobility, network entities, etc.). The second part of this thesis describes the SS7 signaling protocols, SIGTRAN and MAP protocol. The final part deals with design of the emulator.
55

Emulador de turbina eólica : uma ferramenta para o estudo experimental e computacional /

Oliveira, José Rodrigo de. January 2019 (has links)
Orientador: André Luiz Andreoli / Resumo: As fontes renováveis de energia apresentam-se como solução para problemas relacionados ao aumento da demanda por energia elétrica e crescimento dos níveis de emissão de gás carbônico, uma vez que são não poluentes, limpas e abundantes. Aproveitamentos eólicos se mostram como uma das mais promissoras fontes de energia renovável, e por essa razão as pesquisas envolvendo este tipo de aproveitamento têm despertado grande interesse na comunidade científica. Este trabalho apresenta o desenvolvimento de um emulador de turbina eólica (ETE), uma ferramenta de apoio às investigações experimentais capaz de reproduzir o comportamento mecânico dinâmico de uma turbina eólica através de uma malha de controle digital em configuração de hardware-in-the-loop atuando sobre um acionamento eletrônico de uma máquina de indução Operando como fonte de força motriz, o ETE torna mais fácil a avaliação dinâmica de geradores e seus sistemas de controle associados voltados às aplicações envolvendo energia eólica. A pesquisa apresenta uma revisão bibliográfica sobre o estado da arte, a modelagem e a implementação experimental de um emulador de turbina eólica utilizando um motor de indução trifásico (MIT) acionado por um inversor de frequência. Para isso, é implementado um controle em malha fechada de conjugado e velocidade. Este controle faz com que o acionamento eletromecânico representado pelo MIT e inversor de frequência apresente em seu eixo o comportamento de uma turbina eólica conforme os parâmetros... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
56

Cost-efficient method forlifetime extension ofinterconnectedcomputer-based systems / Kostnadseffektiv metod för livstidsförlängning avsammanlänkade datorbaserade system

Holmberg, Wilhelm January 2021 (has links)
Lifetime and obsolescence of components for computer-based systems poses issues for continued usage and maintenance of the systems. This thesis investigates possible alternatives for lifetime extension of a train identification system used in Stockholm Metro. Research of other train identification systems available on the market were made to enable a cost comparison between lifetime extension and system replacement. Methods for extending lifetime of computer-based system, where components are obsolete, were investigated. Since most system documentation was inaccessible a reverse- engineering approach was chosen. Through usage of electrical schematics acquired and open-source hardware descriptions a hardware emulator was developed, which is directly compatible with the existing hardware. The total amount of resources used indicates it is possible to extend the systems lifetime at a low cost, as compared to the cost of system replacement. / Livslängd och åldrande av komponenter för datorbaserade system utgör problem för fortsatt användande och underhåll av systemen. Den här avhandlingen undersöker möjliga alternativ för livstidsförlängning av ett tågidentifieringssystem som används i Stockholms tunnelbana. Efterforskningar av andra tågidentifieringssystem tillgängliga på marknaden genomfördes för att möjliggöra en kostnadsjämförelse mellan livstidsförlängning och systemutbyte. Metoder för förlängning av livslängd av datorbaserade system, där komponenter är föråldrade, undersöktes. Då stora delar av systemdokumentationen inte var tillgänglig valdes baklängesutveckling som strategi. Genom användande av förvärvade elscheman och öppen-källkod hårdvarubeskrivningar kunde en hårdvaruemulator utvecklas, vilken är direkt kompatibel med befintlig hårdvara. Den totala resursanvändningen indikerar att det är möjligt att förlänga systemets livslängd till en låg kostnad, jämfört med kostnaden för ett systembyte.
57

Cost-Effective, Focused Instrumentation for TT&C/COMMS Engineering

Williams, Steve 10 1900 (has links)
ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / The need for sophisticated tools in the expanding areas of Telemetry, Tracking and Control/Command (TT&C) and Communications (COMMS) system simulation, development, verification, analysis, maintenance, debug, and education is well understood. Emerging requirements for these toolsets include features, ease-of-use, performance, and price points that specifically address telemetry and signals work. And, while not yet as available, understood, or pervasively installed, these economical and focused tools are displacing high-cost, general-purpose Test and Measurement (T&M) equipment at an increasing rate.
58

An aircraft based emulation platform and control model for LEO satellite antenna beam steering

Kruger, Iwan Carel 12 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: A joint project between the KU Leuven and Stellenbosch Universities was at the time of this thesis underway to develop a space borne electronically beam steerable antenna and the associated ground-space segments. This thesis covers the development of an aircraft based satellite emulator to facilitate convenient aircraft based testing of an antenna array, intended for low earth orbit satellite deployment and subsystems to control the antenna array. A flight strategy is developed to emulate such a satellite pass as best possible, with the strategy implemented in software on in-flight PC hardware. A full interface between the aircraft avionics and satellite bus system has been developed to enable generation of the required antenna steering commands and to create a satellite bus image to the payload. Successful test results are presented, as obtained from the actual aircraft ight simulator. The thesis describes the successful development and testing of a low altitude flight test strategy for certain satellite borne systems, as a cost-effective and realistic interim step to actual and very expensive space flight testing. / AFRIKAANSE OPSOMMING: 'n Gesamentlike projek deur KU Leuven en Stellenbosch Universiteit was tydens die verloop van hierdie tesis besig met die ontwikkeling om 'n ruimte gebaseerde elektroniese straal beheerde antenna en geassosieerde substelsels daar te stel. Hierdie tesis handel oor die ontwikkeling van 'n vliegtuig gebaseerde satelliet emulator om die toetsing van 'n elektroniese stuurbare antenna, wat bedoel is vir 'n lae aardse wentelbaan, te fasiliteer en die ontwikkeling van substelsels wat die stuurbare antenna beheer. 'n Vlug strategie is ontwikkel om so 'n satelliet wentelbaan so na as moontlik te emuleer. Die strategie word dan geïmplementeer in die sagteware van die aanboord vlug rekenaar. 'n Intervlak tussen die vliegtuig instrumente en satellietbus is ontwikkel om die generering van die nodinge instruksies te fasiliteer en om 'n virtuele satellietbus vir die res van die satelliet stelsel te skep. Suksesvolle toets resultate word getoon wat met behulp van 'n vliegtuig simulator verkry is. Die tesis beskryf die suksesvolle ontwikkeling en toetsing van 'n lae vlugtoets strategie vir satelliet stelsels, as 'n koste effektiewe en realistiese tussenstap, tot baie duur ruimte vlugtoetsing.
59

Investigating the potential for improving the accuracy of weather and climate forecasts by varying numerical precision in computer models

Thornes, Tobias January 2018 (has links)
Accurate forecasts of weather and climate will become increasingly important as the world adapts to anthropogenic climatic change. Forecasts' accuracy is limited by the computer power available to forecast centres, which determines the maximum resolution, ensemble size and complexity of atmospheric models. Furthermore, faster supercomputers are increasingly energy-hungry and unaffordable to run. In this thesis, a new means of making computer simulations more efficient is presented that could lead to more accurate forecasts without increasing computational costs. This 'scale-selective reduced precision' technique builds on previous work that shows that weather models can be run with almost all real numbers represented in 32 bit precision or lower without any impact on forecast accuracy, challenging the paradigm that 64 bits of numerical precision are necessary for sufficiently accurate computations. The observational and model errors inherent in weather and climate simulations, combined with the sensitive dependence on initial conditions of the atmosphere and atmospheric models, renders such high precision unnecessary, especially at small scales. The 'scale-selective' technique introduced here therefore represents smaller, less influential scales of motion with less precision. Experiments are described in which reduced precision is emulated on conventional hardware and applied to three models of increasing complexity. In a three-scale extension of the Lorenz '96 toy model, it is demonstrated that high resolution scale-dependent precision forecasts are more accurate than low resolution high-precision forecasts of a similar computational cost. A spectral model based on the Surface Quasi-Geostrophic Equations is used to determine a power law describing how low precision can be safely reduced as a function of spatial scale; and experiments using four historical test-cases in an open-source version of the real-world Integrated Forecasting System demonstrate that a similar power law holds for the spectral part of this model. It is concluded that the scale-selective approach could be beneficially employed to optimally balance forecast cost and accuracy if utilised on real reduced precision hardware.
60

Metodologia para desenvolvimento e aplicação de um emulador de redes elétricas inteligentes em ambiente controlado. / Methodology for developing and application of a Smart Grid emulator in a controlled environment.

Luiz Henrique Leite Rosa 25 June 2018 (has links)
O presente trabalho visa propor uma metodologia para desenvolvimento e aplicação de um inovador emulador de redes elétricas inteligentes (REIs) para testes sistêmicos de funcionalidades de Smart Grids envolvendo dispositivos inteligentes (hardware) e sistemas de tecnologia da informação (software) em ambiente laboratorial. Além de dar uma dimensão da importância dos laboratórios de redes elétricas inteligentes para a pesquisa do tema, o levantamento bibliográfico apresentado neste trabalho permite concluir que as pesquisas envolvendo hardware-in-the-loop (HIL) tendem a concentrar suas análises nos equipamentos de hardware testados, como dispositivos de medição, equipamentos de potência (inversores de frequência e outros), dispositivos de controle e seus algoritmos e não em estudos que envolvam análises mais sistêmicas e interações dos dispositivos com sistemas de TI normalmente presentes nos Centros de Operação da Distribuição (COD), os quais cumprem papéis cada vez mais importantes nas funcionalidades de Redes Inteligentes. A metodologia proposta parte da premissa de que um ambiente para testes de funcionalidades de Smart Grids deve permitir análises sistêmicas, não apenas focadas nos dispositivos de controle de uma porção particular da rede ou sistemas de automação específicos, mas devem envolver a maior porção de rede possível e necessária para a correta representação das redes elétricas inteligentes. Neste sentido, a metodologia define e caracteriza os principais módulos e etapas de desenvolvimento de um emulador de redes elétricas inteligentes, ao mesmo tempo em que propõe soluções para os desafios de integração destes módulos, aplicando conceitos de hardware-in-the-loop, software-in-the-loop (SIL), e simulação com sincronização orientada a evento, além de propor soluções com simulação de sistemas de potência em regime permanente e hardware de baixo custo que permitiram o desenvolvimento do emulador de redes em laboratório de Smart Grid. As principais características do emulador de REIs desenvolvido e implementado no laboratório de Smart Grid, conforme a metodologia proposta, também são descritas neste trabalho. Por fim, são apresentados os casos teste, mais especificamente provas de conceito, envolvendo redes de teste IEEE/PES e redes reais das concessionárias do grupo EDP, financiador do projeto de implantação do laboratório no âmbito do Programa de P&D ANEEL, os quais serviram de base para a avaliação do desempenho do emulador e discussões finais sobre as contribuições da metodologia de desenvolvimento proposta neste trabalho. / This work aims to proposing a methodology for the development and application of an innovative Smart Grid emulator for systemic testing of Smart Grids functionalities involving intelligent devices and information technology systems in a laboratory environment. Besides demonstrating the importance of the Smart Grid for the subject research, the literature review clarifies that the research involving hardware-in-the-loop (HIL) tends to concentrate its analyses in the equipment under test, such as power devices, control devices and their algorithms. Instead, it should consider systemic studies involving the interaction of these devices with Operation Centre IT systems, so relevant to the Smart Grid functionalities. The proposed methodology is based on the premise that an environment for testing Smart Grids functionalities should allow systemic analysis instead of focusing only on control devices of a specific area or specific automation systems. Instead, it should involve a more detailed representation of the network that is necessary for the correct representation of the Smart Grid. In this direction, the methodology defines and characterizes the development stages and main modules of a Smart Grid emulator and proposes solutions for integration issues. It applies concepts of hardware-in-the-loop, software-in-the-loop (SIL), simulation with event-driven synchronization, besides steady-state power simulation and low-cost hardware solutions that enabled the development of the Power grid emulator at a Smart Grid laboratory. The main features of the Smart Grid emulator developed and implemented at the Smart Grid laboratory, according to the proposed methodology, are also described in this work. Finally, the description of the Smart Grid laboratory, test cases and proofs of concepts involving IEEE/PES test feeders and real networks of the EDP utility, sponsor of the project for laboratory implementation under the ANEEL R&D Program, are presented to prove the Emulator performance and to discuss the contribution of the methodology herein proposed.

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