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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.
571

Ciência cidadã por meio de estações modulares: construindo as condições para um monitoramento meteorológico colaborativo / Citizen science through modular stations : building the conditions for a collaborative meteorological monitoring

Alves, Leonardo Sehn January 2018 (has links)
Foi desenvolvido um protótipo de hardware de sistema de monitoramento meteorológico como tecnologia aberta e livre e voltado para a ciência cidadã, chamado de Estações Meteorológicas Modulares (EMM). Foram considerados critérios de acessibilidade dos materiais e facilidade de modificação no desenvolvimento do projeto. Todos os programas utilizados no desenvolvimento são softwares livres. Um dos elementos desenvolvidos, a placa de controle das EMM, possibilita medir diferentes parâmetros meteorológicos, além de realizar o registro dados e envio para um servidor. Também possibilita a inclusão de novos sensores. Por todos esses fatores, é considerada satisfatória quanto a sua funcionalidade. A estrutura mecânica das EMM atingiu um patamar de preço acessível a indivíduos e organizações como escolas e associações de moradores de bairro, e apresenta fácil adaptabilidade a diferentes condições de instalação. O custo total do sistema ficou abaixo de alternativas proprietárias amadoras e significativamente abaixo de alternativas proprietárias profissionais. Soluções acessíveis para alguns elementos da EMM ainda requerem testes mais aprofundados. Parte das ferramentas utilizadas na fabricação da placa de controle ainda carece de maior disseminação junto à sociedade para acessibilizar o sistema das EMM. Os registros de desenvolvimento do trabalho foram feitos em forma de documentação aberta por meio de cadernos de laboratório abertos. As atividades de fabricação, montagem e instalação das EMM foram feitas seguindo métodos colaborativos chamados de Encontros de Fabricação Colaborativa e Mutirões das EMM. O resultado deste trabalho, unindo as documentações, os registros dos métodos colaborativos de fabricação, montagem e instalação e as consolidadas oficinas do projeto, é sintetizado no Guia da Comunidade EMM. Este é um roteiro para quem quiser fazer parte e ampliar uma rede de monitoramento ambiental colaborativo com as EMM, e é baseado em atividades educacionais para compreensão dos diferentes elementos da ferramenta e para a emancipação tecnológica. Uma das EMM foi comparada com uma estação automática oficial do Instituto Nacional de Meteorologia (INMET). Nessas comparações, as medidas de temperatura e pressão atmosférica apresentaram diferenças menores do que a acurácia dos sensores, enquanto a umidade relativa do ar apresentou uma diferença acima da acurácia do sensor. Este foi um primeiro passo de validação das EMM. / It was developed the hardware prototype of a meteorological monitoring system as free and open source hardware with focus on citizen science. The system is called Estações Meteorológicas Modulares (EMM, from Portuguese Modular Meteorological Stations). Affordability and reachability of materials and ease of remix were criteria considered in the development of this project. All the programs used in the development are free software. One of the elements developed, the control board of the EMM, is considered satisfactory in terms of: the parameters it enables to measure, the functionalities of communication and register of data, and the possibility of inclusion of new sensors.. The resulting solution to the mechanical structure of the EMM is low cost, affordable to schools and neighborhood associations, and is easy to adapt to different conditions of installation. The whole cost of the system is lower than proprietary amateur alternatives and significantly lower than proprietary professional solutions. Reachable and affordable solutions to some elements of the EMM still need some deeper testing. Some of the tools used to produce the control board still need a broader dissemination among the society in order to ensure the reachability and affordability of the EMM system. The work development registers were made as open documentation by means of open laboratory notebooks. The EMM fabrication, mounting and installations activities were made as collaborative methods called Encontros de Fabricação Colaborativa (from Portuguese, Collaborative Fabrication Gatherings) and Mutirões of the EMM. The result of this work, merging the documentation, the register of collaborative methods of fabrication, mounting and installations, and the consolidated workshops of the EMM project, are synthesized in the EMM Community Guide. This is a script to the ones who want to make part and expand the collaborative environmental monitoring network with the EMM, and it is based in educational activities to comprehend the different elements of the tool and to promote the technological emancipations. One of the EMM was compared to an official automatic meteorological station from Instituto Nacional de Meteorologia (INMET, from Portuguese Meteorology National Institute). In this comparison, the temperature and atmospheric pressure measurements showed differences lower than the accuracy of the sensors used, and the relative air humidity presented a difference higher than the accuracy of the sensor. This was the first step to validate the EMM.
572

Desenvolvimento de um código computacional aberto de análise quantitativa para determinação de radionuclídeos por espectrometria gama com detectores semicondutores / Development of an open source software of quantitative analysis for radionuclide determination by gamma-ray spectrometry using semiconductor detectors

Marcelo Francis Máduar 26 May 2010 (has links)
A quantificação da atividade de radionuclídeos emissores de raios gama em amostras medidas por espectrometria gama com detectores HPGe depende da análise dos fotopicos presentes no espectro, especialmente da determinação exata das suas áreas líquidas. Tal análise é geralmente realizada com o auxílio de ferramentas de software proprietário. Este trabalho apresenta uma metodologia, descrição de algoritmos e um aplicativo de código aberto, denominado OpenGamma, para a busca e análise de fotopicos a fim de se obter seus parâmetros relevantes e as atividades dos radionuclídeos na amostra. A implementação computacional é distribuída sob licença aberta para o código principal e com o uso de pacotes de software aberto para o projeto da interface e para bibliotecas matemáticas. O procedimento para a busca de picos é realizado em três etapas. Primeiramente, executa-se uma pesquisa preliminar com o método da segunda diferença, que consiste na geração de um espectro derivado para a busca de picos candidatos. Na segunda etapa, calculam-se as larguras experimentais dos picos, dos quais escolhem-se aqueles bem formados e isolados para a obtenção da função de ajuste da largura vs. canal, por meio do método de Levenberg-Marquardt para ajustes não-lineares. Por fim, regiões do espectro com picos agrupados são delimitadas e novo ajuste não-linear é aplicado a cada região para a obtenção dos termos da linha de base e dos fotopicos. A partir destes termos, são calculadas as áreas líquidas dos picos. Para a determinação da atividade, curvas de calibração de eficiência previamente obtidas, bem como dados de transições gama dos radionuclídeos, são incorporadas ao código e aplicadas. O código foi escrito em linguagem C++ e a interface foi desenvolvida com a ferramenta Qt. Para as funções matemáticas e procedimentos de ajuste, foi usada a biblioteca científica GNU (GSL). A validação de código foi feita por meio da análise de: 1) espectros sintéticos de teste da AIEA, especialmente desenhados para a avaliação de desempenho de software; 2) espectros obtidos com amostras de exercícios de intercomparação e 3) espectros da rotina de trabalho do Laboratório de Radiometria Ambiental (LRA) do IPEN e analisados com o aplicativo comercial InterWinner. Os resultados obtidos são consistentes com os valores de referência e com aqueles obtidos pelo aplicativo citado, sugerindo que o código OpenGamma pode ser utilizado com segurança na espectrometria de raios gama de uso geral. / Radioactivity quantification of gamma-ray emitter radionuclides in samples measured by HPGe gamma-ray spectrometry relies on the analysis of the photopeaks present in the spectra, especially on the accurate determination of their net areas. Such a task is usually performed with the aid of proprietary software tools. This work presents a methodology, algorithm descriptions and an open source application, called OpenGamma, for the peak search and analysis in order to obtain the relevant peaks parameters and radionuclides activities. The computational implementation is released entirely in open-source license for the main code and with the use of open software packages for interface design and mathematical libraries. The procedure for the peak search is performed on a three step approach. Firstly a preliminary search is done by using the second-difference method, consisting in the generation of a derived spectrum in order to find candidate peaks. In the second step, the experimental peaks widths are assessed and well formed and isolated ones are chosen to obtain a FWHM vs. channel relationship, by application of the Levenberg-Marquardt minimization method for non-linear fitting. Lastly, regions of the spectrum with grouped peaks are marked and a non-linear fit is again applied to each region to obtain baseline and photopeaks terms; from these terms, peaks net areas are then assessed. For the activity determination, previously obtained efficiency calibration curves, as well as nuclides gamma-ray data, are incorporated in the code and applied. The code was developed in C++ language and the interface was developed with Qt GUI software toolkit. GNU scientific library, GSL, was employed to perform fitting procedures as needed. Validation of code was done by analyzing: 1) synthetic test spectra from IAEA, especially designed for software performance evaluation; 2) spectra obtained from samples of intercomparison exercises and 3) spectra from routine activities of the Environmental Radiometric Laboratory (LRA) at IPEN and analyzed with the commercial software package InterWinner. Results obtained are consistent with the reference values and with those obtained by the aforementioned package. The results suggest that the OpenGamma code could be safely used in general-purpose gamma-ray spectrometry.
573

Manejo populacional de cães e gatos: métodos quantitativos para caracterizar populações, identificar prioridades e estabelecer indicadores / Dog and cat population management: quantitative methods to characterize populations, identify priorities and to establish indicators

Baquero, Oswaldo Santos 05 October 2015 (has links)
O manejo populacional de cães e gatos é um conjunto de estratégias para controlar e prevenir problemas relacionados com o convívio entre esses animais e os seres humanos. Nesta tese é proposto um fluxo de trabalho baseado em métodos quantitativos, para auxiliar o planejamento, implementação e monitoramento de programas de manejo populacional de animais de companhia. Ao seguir o fluxo de trabalho é possível coletar dados para caracterizar populações, analisar esses dados para propor intervenções e avaliar o efeito das intervenções. A proposta foi baseada na articulação de cinco pesquisas. Na primeira pesquisa foi implementado de um desenho amostral complexo para caracterizar a população de cães e gatos domiciliados de Votorantim, São Paulo. Na segunda pesquisa que foi baseada nos dados levantados na primeira, foram usadas análises de correspondências múltiplas para identificar perfis de opiniões públicas em relação ao abandono de cães e gatos. Na terceira pesquisa foi avaliada a validade do desenho amostral usado na primeira pesquisa, mediante simulações estocásticas. Na quarta pesquisa foi desenvolvido um modelo matemático de manejo populacional que permite priorizar as intervenções de acordo com o efeito que produzem. Na quinta pesquisa foi desenvolvido um modelo matemático para avaliar a eficiência do controle reprodutivo realizado com contraceptivos de efeito reversível. Os modelos das duas últimas pesquisas foram baseados em sistemas acoplados de equações diferenciais e em análises de sensibilidade global e local. A proposta foi implementada em um software de código aberto, o pacote do R capm, que pode ser incorporado na rotina de trabalho dos setores envolvidos no manejo populacional de animais de companhia / Dog and cat population management is a set of strategies to control and prevent problems related with the coexistence between those animals and human beings. In this thesis it is proposed a work-fiow based on quantitative methods to support the planning, implementation and mo- nitoring of companion animal population management programs. Following the work-fiow, it is possible to collecf data to characterize populations, analyze that data to propose interventions and assess the effect of interventions. The proposal was based on the articulation of five rese- arches. In the first research, a complex sampling design was implemented to characterize the owned dog and cat populations of Votorantim, São Paulo. In the second research, which was based on data from the first one, public opinion profiles regarding dog and cat abandonment were identified using multiple correspondence analysis. In the third research, the validity of the sampling design used in the first research was assessed through stochastic simulations. In the fourth research, a mathematical model of population management was developed. With that model, it is possible to prioritize interventions according to the effect they produce. In the fifth research, a mathematical model was developed to assess the efficiency of reproductive control based on contraceptives with reversible effect. The models of the last two researches were based on systems of coupled differential equations, and on global and local sensitivity analysis. The proposal was implemented in an open source software, the R package capm, that can be incorporated in the working routine of sectors involved with companion animal population management
574

Sistemas de Arquivos Distribuídos / Distributed File Systems

Kon, Fabio 08 November 1994 (has links)
Este trabalho se inicia com uma discussão sobre as principais características dos Sistemas de Arquivos Distribuídos, ou seja, espaço de nomes, localização, cache, consistência, replicação, disponibilidade, escalabilidade, heterogeneidade, tolerância a falhas e segurança. Analisamos diversos sistemas de arquivos existentes quanto a estas características dando especial atenção aos sistemas NFS, Andrew, Coda, Sprite, Zebra, Harp, Frolic e Echo. Descrevemos alguns modelos analíticos para o comportamento de sistemas de arquivos distribuídos e, em seguida, apresentamos um novo modelo para sistemas baseados em leases - um mecanismo para a garantia de consistência em sistemas distribuídos. Finalmente, descrevemos a nossa implementação do sistema de arquivos distribuído SODA - que utiliza leases - apresentando dados sobre o seu desempenho. / We begin with a discussion of some of the main characteristics of Distributed File Systems, namely locality, name space, cache, consistency, replication, availability, scalability, heterogeneity, fault tolerance and security. We analyze several file systems based on these characteristics. We focus mainly on NFS, Andrew, Coda, Sprite, Zebra, Harp, Frolic, and Echo. We then describe some analytical models of the behavior of distributed file systems. After that we present a new model of systems based on leases - a mechanism to assure consistency on a distributed system. Finally we describe our implementation of the SODA distributed file system - which uses leases - presenting some results on its performance.
575

Collaboration massivement distribuée et gestion du savoir en ligne: le cas de la communauté WordPress (2003-2008). "Code is poetry", but a "documentation resource should be managed"

Ruzé, Emmanuel 04 December 2009 (has links) (PDF)
Le déploiement du numérique se caractérise par une montée en puissance des communautés sur Internet. Celles-ci ont permis l'émergence de formes organisationnelles significativement nouvelles intéressant les managers et supportées par les technologies de l'information, en particulier les mouvements open-source puis Web 2.0.. Cependant, l'articulation entre les modes d'organisation sous-jacents à ces deux courants parfois confondus n'a pas été comprise de façon exhaustive. En particulier, les usages de la technologie wiki se situent à la frontière entre les deux mouvements ; ils constituent un point de tensions potentiel entre les pratiques de l'open-source et les principes de « collaboration massivement distribuée » caractéristiques des sites à « contenu ouvert ». Cette thèse propose une étude de cas en profondeur, celle du déploiement dans une communauté open-source d'un système d'information fondé sur la technologie wiki et ouvert aux contributions volontaires. La communauté WordPress l'a implémenté afin de centraliser et rendre public le savoir nécessaire à la viabilité du projet. Nous montrons dans quelle mesure des formes de gouvernance ont émergé pendant l'histoire de la communauté afin de gérer ce bien informationnel collectif : formes d'articulation avec la communauté et d'appropriation du savoir, routines, collaboration structurée entre volontaires, constitution dynamique du bien collectif. Notre thèse propose donc une contribution à la compréhension des formes informelles de gouvernance qui conditionnent la viabilité des biens publics numériques. Nous adoptons une approche micro-historique sur la période 2003-2008 à partir de matériaux d'archives traités selon plusieurs méthodologies qualitatives et quantitatives. Nous montrons ensuite la fécondité des concepts de l'économie cognitive pour comprendre l'émergence des formes de gouvernance observées. Cette thèse fut en effet une collaboration entre les laboratoires CRG et CREA de l'Ecole polytechnique.
576

Sécurité des systèmes d'exploitation répartis : architecture décentralisée de méta-politique pour l'administration du contrôle d'accès obligatoire.

Blanc, Mathieu 19 December 2006 (has links) (PDF)
Dans cette thèse, nous nous intéressons au contrôle d'accès obligatoire dans les systèmes d'exploitation répartis. Nous présentons une approche novatrice fondée sur un modèle de méta-politique pour l'administration décentralisée des noeuds du système réparti. Ces travaux visent la sécurité des grands réseaux partagés, i.e. les clusters, grilles ou ensembles de noeuds coopérant par Internet. L'architecture que nous proposons garantit des propriétés de sécurité globales et une bonne tolérance aux pannes. Ces propriétés, non prises en comptes par les modèles de contrôle d'accès classiques, sont obtenues grâce à notre méta-politique. Nous en présentons une formalisation, puis nous exhibons une technique de vérification garantissant l'absence de flots d'information illégaux au sein des noeuds du réseau. Nous décrivons ensuite comment le modèle peut être étendu pour la détection d'intrusions. Enfin, nous proposons une implantation supportant différents systèmes cibles tels que SELinux et grsecurity.
577

Intellectual Property Rights in Software : A Critical Investigation from an Ethical Perspective

Schulz, Axel January 2004 (has links)
<p>The development of software was considered until the beginning of the 1990th as a cathedral like product development in closed companies. This way of development changed in the last decade. Open source software (OSS) development challenged this consideration significantly. OSS is produced in co-operation by skilled people, distributed and used by many moral agents. The result, the software itself, can be studied and modified. Herein is the main incentive for people to develop the software. In such a mode of production the freedom to access knowledge and information (=source code) is a necessity to produce the artifact (software).</p><p>Software is a digital entity. The main difference in comparison to natural resources like oil, land, minerals is that it can be used and reproduced without losses. It lacks the capacity of getting naturally scarce. Contemporary intellectual property rights assume implicitly that goods might getting scarce one day. Imbedded in the term intellectual property is also an idea of "fencing" objects. In this thesis I will argue that anartificial"encing"of digital objects might cause unintentional bad consequences for the society. An other quality intellectual property rights are claimed to have is that they serve as an incentive for inventors/authors to produce new inventions and ideas. The practice of OSS development works without such an incentive provided by intellectual property rights.</p><p>The moral conflict, which I attempt to unravel in this work deals with the question to what extend the application of intellectual property rights in software is necessary and how restrictive particular property rights in digital objects should be - if there should be any at all. Knowledge as the factor of production is of the same value in knowledge societies as land was for agrarian societies. The difference is in the mode of production and the un-limitless availability of digitalized knowledge. I argue that the"protection"of knowledge, and software is knowledge, has to be carefully revised in so called knowledge societies.</p>
578

Utvärdering av Mock Objekt Bibliotek : ur ett interaktionsbaserat perspektiv

Billskog, David January 2007 (has links)
<p>Att skriva enhetstester är en viktig del i nya populära systemutvecklingsmetoder som extreme programming. Med testdriven utveckling skriver man testerna innan den källkod som skall testas. Ett vanligt problem med dessa tester är att de blir beroende av delar i systemet som inte är intressant för själva testen. Mock objekt är en teknik som gör det enkelt att isolera tester från allt som inte är relaterat till det som skall testas.</p><p>Det finns två sätt att se på mock objekt. Den traditionella synen är att mock objekt skall användas som ett verktyg vid isolering av externa system. Den alternativa synen är att mock objekt är ett designverktyg som kan driva fram en bättre design i systemet. I denna uppsats utvärderas ett antal mock objekt bibliotek ur detta nyare perspektiv. Resultatet visar att det finns åtskilliga skillnader mellan biblioteken.</p>
579

The Instant Generation : - hur ser ungdomars attityder till fildelning ut?

Strand, Carl January 2006 (has links)
<p>Abstract:</p><p>Title: Engelska (Svenska)</p><p>Number of pages: 40 (47 including appendix)</p><p>Author: Carl Strand</p><p>Tutor: Göran Svensson</p><p>Course: Media and Communication Studies C</p><p>Period: Fall 2005</p><p>University: Division of Media and Communication, Department of Information Science, Uppsala University</p><p>Purpose/Aim: The purpose of this essay is to analyze how young people, in the ages 18 to 25, relate to the subject of file sharing, and what their attitudes to this phenomenon are. I aim to describe how they use file sharing, their knowledge about it, how their usage have changed due to the new copyright law, what their stands are on the question of resource control and management on the Internet, and what they think of the future of file sharing.</p><p>Material/Method: The method being used is a qualitative focus group interview model, used to investigate how young people look at the subject of file sharing. The results of the interviews is then applied to a theoretical framework based on thoughts of Denis McQuail, Lawrence Lessig concerning creativity, copyright, resource management and file sharing on the Internet</p><p>Main Results: My conclusion is that the widespread file sharing habits of young people is not only caused by the temptation of getting free stuff, but of the lack of commercial and legal alternatives. Youths are willing to pay for media if the distribution is superior to the illegal file sharing alternative. They are a generation of young people that has grown up in a society where the tendency in many fields has been to make everything faster and more effective. They want to be able to get everything, and they want it fast. They are what I call the Instant Generation.</p><p>Keywords: File sharing, attitudes, focus groups, Darknet, Open Source, free resources, free creativity</p>
580

Library Communication Among Programmers Worldwide

Berglund, Erik January 2002 (has links)
Programmers worldwide share components and jointly develop components on a global scale in contemporary software development. An important aspect of such library-based programming is the need for technical communication with regard to libraries – library communication. As part of their work, programmers must discover, study, and learn as well as debate problems and future development. In this sense, the electronic, networked media has fundamentally changed programming by providing new mechanisms for communication and global interaction through global networks such as the Internet. Today, the baseline for library communication is hypertext documentation. Improvements in quality, efficiency, cost and frustration of the programming activity can be expected by further developments in the electronic aspects of library communication. This thesis addresses the use of the electronic networked medium in the activity of library communication and aims to discover design knowledge for communication tools and processes directed towards this particular area. A model of library communication is provided that describes interaction among programmer as webs of interrelated library communities. A discussion of electronic, networked tools and processes that match such a model is also provided. Furthermore, research results are provided from the design and industrial valuation of electronic reference documentation for the Java domain. Surprisingly, the evaluation did not support individual adaptation (personalization). Furthermore, global library communication processes have been studied in relation to open-source documentation and user-related bug handling. Open-source documentation projects are still relatively uncommon even in open-source software projects. User-related Open-source does not address the passive behavior users have towards bugs. Finally, the adaptive authoring process in electronic reference documentation is addressed and found to provide limited support for expressing the electronic, networked dimensions of authoring requiring programming skill by technical writers. Library communication is addressed here by providing engineering knowledge with regards to the construction of practical electronic, networked tools and processes in the area. Much of the work has been performed in relation to Java library communication and therefore the thesis has particular relevancefor the object-oriented programming domain. A practical contribution of the work is the DJavadoc tool that contributes to the development of reference documentation by providing adaptive Java reference documentation. / On the day of the public defence the title of article I was: Designing Electronic Library Reference Documentation.

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