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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.
61

Estudos de confiabilidade de redes GNSS

Collischonn, Carolina January 2015 (has links)
O principal objetivo dessa dissertação foi estudar a confiabilidade de redes GNSS. Em termos metodológicos foram analisadas redes obtidas pelos seguintes métodos: redes com inclusão de linhas-base repetidas, por posicionamento relativo e pelo Posicionamento por Ponto Preciso (PPP). A rede GNSS utilizada possui seis estações pertencentes a Rede Brasileira de Monitoramento Continuo (RBMC) do Instituto Brasileiro de Geografia e Estatística (IBGE). As estações se localizam no oeste do estado de São Paulo. Para atingir o objetivo do trabalho foram estruturadas as seguintes hipóteses: a inserção de novas linhas-base em uma estrutura de rede GNSS possibilita melhorar a eficiência na detecção de outliers e aumenta a confiabilidade da rede, bem como, existe um limiar de número de linhas-base que a partir dele não se verifica mais melhora na confiabilidade. E, a outra hipótese, é que redes GNSS podem ser formadas a partir do PPP e ter parâmetros de qualidade estimados (de precisão e de confiabilidade), requisito fundamental para o uso em aplicações geodésicas. Com relação a primeira hipótese foi gerado um artigo onde é aplicado o controle de qualidade por meio da teoria de confiabilidade convencional analisando a melhora da confiabilidade a partir da inclusão de linhas-base repetidas em rede GNSS. Primeiramente foi realizado o ajustamento por mínimos quadrados da rede GNSS e calculadas as medidas de confiabilidade: o número de redundância local, a confiabilidade interna, externa e razão tendência-ruído. As linhas-base repetida na rede foram selecionadas a partir da análise de qual observação possuía menor valor de número de redundância local. O ajustamento foi realizado novamente, bem como o cálculo das medidas de confiabilidade. Esse procedimento foi repetido cinco vezes, quando se verificou a estabilização dos resultados. A segunda hipótese resultou no artigo onde foi apresentada uma metodologia de desenvolvimento de rede utilizando dados GNSS processados pelo PPP. Nesse artigo foi aplicada a teoria convencional de confiabilidade para verificar a potencialidade da metodologia apresentada. Diferentes tempos de rastreio foram empregados nos experimentos. O serviço de processamento de PPP utilizado é o fornecido pelo IBGE. A partir dos resultados foram feitas análises para verificar a aplicabilidade da metodologia descrita em rede com dados GNSS de 24, 6 e 4 horas de rastreio. Após o ajustamento, os testes global e o data snooping foram aplicados. Também é analisada a confiabilidade da rede com o objetivo de avaliar o método proposto, além de verificar a influência do tempo de rastreio nos resultados. / The main goal of the present dissertation was to study the reliability of GNSS networks. In methodological terms networks obtained from the following methods were analyzed: networks with including repeated baselines, relative positioning and Precise Point positioning (PPP). The GNSS network used has six stations belonging to the Brazilian Network of Continuous Monitoring (RBMC) of the Brazilian Institute of Geography and Statistics (IBGE), located in the west part of São Paulo. In order to achieve the objective of the study the following hypotheses were structured: the insertion of the new baselines in a GNSS network structure enables to improve the efficiency in detecting outliers and increases network reliability, just like, there is a threshold in the number of baselines in which above these number there is no improvement in the reliability. The other hypothesis is that GNSS networks can be formed from the PPP and have its quality parameters estimated (accuracy and reliability), fundamental requirement for geodetic applications. An article was generated regarding the first hypothesis where the quality control trough the conventional reliability theory was applied to analyze the quality improvement from the inclusion of repeated baselines in GNSS network. First, the least squared adjustment was made and then the reliability measures were calculated, which are: local redundancy number, the internal and external reliability and bias to noise - ratio. The repeated base lines in the network were selected by choosing the observations with lowest number of local redundancy. The adjustment and the calculation of the reliability measures were performed again. When this procedure was repeated five times, the stabilization of the results was observed. The second hypothesis resulted in an article in which a methodology of network development using GNSS data processed by the PPP was presented. In this paper the conventional reliability theory was applied to verify the presented methodology capability. Different occupation times were used in the experiments. The PPP processing service used is provided by the IBGE. From the results, analyses were performed to verify the applicability of the methodology described in network with GNSS data of 24, 6 and 4 occupation. After the adjustment, the global and data snooping tests were applied. The network reliability is also analyzed with the objective of evaluating the proposed method. In addition was verifying the influence of occupation time in the results.
62

Avaliação da qualidade do posicionamento por satélites com integração GPS/GLONASS

SILVA, Emanoel Gomes de Sousa 06 March 2015 (has links)
Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-03-23T17:22:47Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissert_EmanoelGomes_vFinal (1).pdf: 3169112 bytes, checksum: 670b4efee57c1d0f5415070a594b6ca0 (MD5) / Made available in DSpace on 2016-03-23T17:22:47Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissert_EmanoelGomes_vFinal (1).pdf: 3169112 bytes, checksum: 670b4efee57c1d0f5415070a594b6ca0 (MD5) Previous issue date: 2015-03-06 / CAPES / O posicionamento geodésico atualmente é realizado em sua maioria a partir do GNSS. Dentre os sistemas disponíveis, o GPS ainda é o mais utilizado na atualidade, porém, o GLONASS está totalmente operacional, o que torna possível a aplicação de sistema multi-constelação no posicionamento geodésico. Os dois sistemas encontram-se em fase de modernização, o que permite estudos e pesquisas relacionadas à integração dos sinais GPS e GLONASS (GPS/GLONASS), seja para fins de posicionamento geodésico ou em outras atividades da comunidade usuária, dentro das engenharias e pesquisas científicas. Dentre os métodos de posicionamento, destaca-se o método PPP, o qual tem sido alvo de muitas investigações e melhoramentos nos últimos anos em função das melhorias nos produtos disponíveis pelos centros do IGS. O PPP em sua forma convencional requer o uso de medidas em duas frequências, órbitas e correções precisas dos erros dos relógios dos satélites, além da modelagem matemática para corrigir os diversos efeitos envolvidos com a propagação dos sinais GNSS e efeitos geodinâmicos afetando as estações terrestres. Uma vez que os diversos efeitos tenham sido corrigidos, espera-se precisão da ordem de poucos centímetros na estimativa de coordenadas no método PPP após algumas horas de coleta de dados. A integração GPS/GLONASS no PPP requer compatibilização entre sistemas de referência e sistemas de tempo. Espera-se que a utilização de dados GPS/GLONASS, forneça melhor geometria para estimativa dos parâmetros, além de proporcionar maior redundância para o ajustamento, o que gera maior confiabilidade (capacidade de detectar erros) nos resultados. Dentro deste contexto, esta pesquisa tem como objetivos investigar a modelagem matemática para a integração de dados GPS/GLONAS no método PPP, além de avaliar a acurácia do posicionamento para dados coletados no Brasil. Análises qualitativas foram realizadas para verificar o impacto da utilização das medidas GLONASS juntamente com medidas GPS no PPP considerando o caso de posicionamento estático e cinemático. A análise das precisões dos parâmetros foi realizada a priori com base na construção da matriz Jacobiana (matriz A), a qual não requer o uso de observações GNSS. A partir desta matriz se obtém a matriz N e sua inversa proporciona a Matriz de Covariância dos parâmetros. Esta tarefa é muito útil, por exemplo, no planejamento de redes Avaliação da qualidade do posicionamento GNSS com integração GPS/GLONASS Emanoel Gomes de Sousa Silva geodésicas e, no caso da integração GPS/GLONASS no método PPP observou-se melhorias nas estimativas das precisões das coordenadas em torno de 30%. A precisão da componente úmida da troposfera, no caso da análise a priori, foi de até 20% com observações em dias distintos de um ano. Para a análise de acurácia no caso de posicionamento cinemático, as coordenadas estimadas no método relativo foram adotadas como referência em relação ao PPP cinemático. No caso de análise de acurácia do PPP estático as coordenadas divulgadas das estações da RBMC e da rede SIRGAS-CON foram adotadas como referência. Foram processados no modo PPP estático dados de cinco estações distribuídas em diferentes latitudes no Brasil ao longo do ano de 2013 com a geração de séries temporais anuais de coordenadas. A melhoria em acurácia posicional ao utilizar integração GPS/GLONASS atingiu máximo de aproximadamente 25%. Além disto, observaram-se melhorias no tempo de convergência do PPP. / The geodetic positioning is currently accomplished in most of part by using GNSS. Among available systems, GPS is still the most widely used nowadays; however GLONASS is totally operational, what turns possible the application of multi-constellation system in the geodetic positioning. Both GPS and GLONASS (GPS/GLONASS) are under modernization process allowing studies about integration of signals either for geodetic positioning purposes or other activities in the engineering field and scientific researches. Among the geodetic positioning methods the PPP method (Precise Point Positioning) has been widely investigated in the last years and experienced many improvements, as for instance due to improvements in available products through IGS centers. The PPP in its conventional form requires the use of measures on two frequencies, precise orbits and correction of satellite clock error as well as adequate mathematical modeling to correct for several effects involved in the spread of GNSS signals and geodynamic effects affecting ground stations. Once the various effects have been corrected, it is expected coordinates accuracy of a few centimeters in the PPP method after a few hours of data collection. The Combined GPS/GLONASS in PPP requires compatibility between reference systems and time systems. It is expected that the use of GPS/GLONASS data, provide better geometry to estimate parameters and also provide increased redundancy for the adjustment, which generates higher reliability (ability to detect errors) in the results. Within this context, the aim of this research is to investigate the mathematical model for the Combined GPS/GLONASS data in the PPP method and evaluate the accuracy of positioning for data collected in Brazil. Qualitative analyzes were performed to verify the impact of using GLONASS together with GPS measurements in PPP considering static and kinematic positioning. Precision analysis of parameters was a priori performed based on the inverse of the matrix N. This task is very useful a for instance in geodetic network planning and for GPS/GLONASS integrations in PPP it was observed improvements of the order of 30% in the estimated precision. The parameter related with tropospheric wet delay was also a priori analyzed and improvements of up to 20% were observed at different days of a year. In the case of kinematic positioning, the coordinates estimated in the relative method were adopted as reference to compute Avaliação da qualidade do posicionamento GNSS com integração GPS/GLONASS Emanoel Gomes de Sousa Silva accuracy of kinematic PPP. Concerning the static positioning it was used as ground truth official coordinates of RBMC stations and SIRGAS-CON network. For the static PPP, it was processed data from five stations distributed in different latitudes along of Brazil in the year 2013 with generations of time series of coordinates. The Improvement in positional accuracy when applying GPS/GLONASS reached maximum value of 25%. Besides that, it was observed improvements in the PPP convergence time.
63

Le partenariat public-privé en infrastructure : évaluation de la performance administrative et des effets démocratiques dans le contexte québécois

Hudon, Pierre-André January 2013 (has links)
Le partenariat public-privé (PPP) est un mode d’approvisionnement gouvernemental qui combine, en une seule entente contractuelle à long terme, toutes les étapes traditionnelles de la réalisation d’une infrastructure : la conception, la construction, l’exploitation, l’entretien et le financement. Au Québec, la décision d’utiliser le mode PPP a été accompagnée d’une série de réformes légales, réglementaires et institutionnelles. Ces réformes ont profondément bouleversé la manière de réaliser les grands projets d’infrastructure. Or, il semble que peu d’analyses aient été effectuées quant aux impacts de ces changements sur la gouvernance démocratique de l’approvisionnement en infrastructure. Cette thèse se penche donc sur le PPP en tant que mécanisme d’approvisionnement, mais aussi en tant que point de départ d’une série de réformes administratives venant influencer considérablement la gouvernance de l’approvisionnement gouvernemental. Le document propose d’abord une relecture et une redéfinition de la gouvernance démocratique à partir de la théorie des études critiques en management et de la théorie des instruments d’action publique. Les réformes récentes de l’administration publique québécoise y sont examinées à la lumière de cette redéfinition. Les politiques d’approvisionnement, ainsi que les critères d’appréciation qui leur sont propres, sont aussi étudiés à la lumière de la théorie critique. Ensuite, de façon plus précise, le mode PPP est étudié en partant de ses origines et des raisons qui ont mené à son adoption. D’un point de vue empirique, trois cas pratiques sont examinés afin de produire, d’une part, une évaluation de la performance administrative du mode PPP et, d’autre part, une caractérisation de ses effets démocratiques. Une attention particulière est portée au mécanisme du « comparateur public », qui fait l’objet d’une analyse financière critique. La thèse en arrive aux conclusions suivantes : D’abord, au niveau micro, soit celui du fonctionnement interne des PPP, les conséquences suivantes sont observables : une définition des besoins plus rigoureuse, mais contraignante à long terme; des économies difficiles à démontrer; une dynamique de confrontation et non de partenariat entre acteurs privés et publics; un entretien contractuellement garanti qui présente un avantage réel étant donné la tendance bien documentée des gouvernements à mal entretenir les infrastructures; et des risques financiers réels, mais pouvant être atténués notamment par le montage financier. Ensuite, au niveau meso, soit celui de l’arrimage avec les principes de la gouvernance démocratique, les conséquences de la mise en œuvre de la politique québécoise des PPP sont les suivantes : un discours trompeur sur les économies réelles, notamment par l’utilisation d’une méthodologie d’analyse financière ambiguë; un modèle de prise de décision laissant place à l’intervention politique illégitime; des difficultés quant à la gestion à long terme des incertitudes; et une imputabilité rendue plus difficile par la contractualisation. Finalement, au niveau macro, soit celui de la redéfinition du rôle de l’État induit par la mise en œuvre de la politique sur les PPP, les conséquences sont les suivantes: une dérive de la gouvernance vers une forme illégitime de contrôle politique; un modèle néolibéral de partenariat non-observable dans la pratique et s’effaçant plutôt au profit d’une logique de compétition classique; et une modernisation inachevée, reposant sur les principes de la gouvernementalité managériale plutôt que sur ceux de la rationalité communicationnelle. La thèse se conclut, au dernier chapitre, par une redéfinition critique de la gouvernance de l’approvisionnement gouvernemental. Cette redéfinition s’appuie sur un certain nombre de propositions de recherche pouvant servir de base à une réforme de la politique d’approvisionnement en infrastructure.
64

Význam vzájemné spolupráce orgánů státní správy a samosprávy a sociálních partnerů (PPP) pro rozvoj cestovního ruchu / The importance of mutual cooperation of the bodies of state administration and local government and social partners for tourism development

Machačová, Romana January 2008 (has links)
Diplomová práce se zabývá partnerstvím veřejného a soukromého sektoru - PPP, z angl. Public Private Partnership. Práce je zaměřena na oblast cestovního ruchu, ve které je vzájemná spolupráce velmi důležitá, neboť v cestovním ruchu dochází ke každodennímu střetu veřejného a soukromého sektoru. Práce ukazuje význam této spolupráce na pilotních projektech České republiky, splňujících definici PPP, a na projektech založených na principu partnerství, které jsou v cestovním ruchu daleko častější. PPP pomáhá rozvíjet infrastrukturu, která je tolik potřebná pro rozvoj cestovního ruchu, a je příležitostí pro regiony a kraje, jak realizovat projekty, které by nemohly provést tradiční cestou.
65

Bariéry aplikace PPP projektů v České republice / Barriers that inhibit application of PPP projects in Czech Republic

Horňáková, Lenka January 2008 (has links)
Main subject of this work characterisation of PPP projects and barriers that inhibit application of PPP projects in Czech Republic. First there are characterised main concepts as public sector and his mission in providing public goods and services. Attention is also paid to characterization of PPP projects and to the differences between providing public goods and services through PPP scheme or by traditional way. Afterwards there is described the whole process of preparation and implementation of a PPP project including the key moments, that can't be ignored. If ignored, it could cause incorrigible faults in the implementation phase. This work also includes analysis of interviews made with a view to find out, how are Czech citizens informed about PPP projects. The produces of this work serve as basis for setting strategy and policy, which should be observed. Otherwise there is a risk that the project won't be finished successfully with positive public evaluation.
66

Public Private Partnerships in Health Care: European PPP models and factors influencing the positive outcome of such ventures / Public Private Partnerships ve zdravotnictví: Evropské PPP modely a faktory ovlivňující pozitivní výsledky těchto podniků

Siroky, Joseph Yan January 2012 (has links)
A number of European countries are turning to private finance for public hospitals and other healthcare infrastructure. Public-private partnerships (PPP) are intended to bind private sector efficiencies, secure appropriate risk transfer between hospital operators, infrastructure owners and other partners, and ensure optimum whole-life asset management. This paper discusses the different factors that influence significantly the outcomes of European PPP ventures, the scope of different PPP models, and experience so far in delivering new infrastructure and stimulating innovation and quality improvements. Finally, it draws conclusions, through recent case studies, on the factors that have a significant influence in shaping PPP models and policies. The methods used were extensive literature research and analysis, further supported by case study analysis of the Pembury Hospital, Braga Hospital, Berlin Buch Hospital and De La Ribera Hospital. The outcome of this paper draws upon the concept of "bundling" of services and concludes that this may be seen as a way of providing more appropriate risk allocation that creates incentives for efficient and effective behavior of the private sector.
67

Value creation over time: the application of IIRC integrated reporting framework to demonstrate the value of MICE business / IIRC統合報告フレームワークを用いた国際会議・MICEビジネスの価値創造モデル

Nishimoto, Keiko 23 September 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(経営科学) / 甲第22817号 / 経営博第11号 / 新制||経営||2(附属図書館) / 京都大学大学院経営管理教育部経営科学専攻 / (主査)教授 若林 靖永, 教授 澤邉 紀生, 教授 若林 直樹 / 学位規則第4条第1項該当 / Doctor of Philosophy in Management Science / Kyoto University / DGAM
68

Porovnání stavu PPP projektů se zahraničím / Comparison of Situation in the Area of PPP Project with Foreign Countries

Belás, Daniel January 2015 (has links)
The diploma thesis „Comparison of situation in the area of PPP project with foreign countries“ is an analysis of the issues connected with realization of projects. Part of diploma thesis is a brief description of problems themselves, their pluses and minuses for which the PPP projects are not widely used and the characteristic of various institutions involved in public private partnership. Part of the work is also a short quetionnaire.
69

Public private partnership policy in Nigeria's infrastructure development landscape : a critical appraisal of the infrastructure Concession Regulatory Act

Abdulsalam, Mutait Mobolanle January 2014 (has links)
Nigeria is rich country in terms of natural resources, It has one of Africa's largest economy, having being endowed with massive natural, human, renewable and non-renewable resources. With a population of about 160 million people which creates a large market for goods and services, rich soil suitable for commercial agriculture, deposits of natural resources including crude-oil, natural-gas, tin, and rock-salt, and cash crops including cocoa, kola-nut, cotton, groundnut and timber, Nigeria has the potential of being one of the largest economy globally and the political hegemony in Africa.1 However, the country has not been able to achieve sustainable development as a result of the deplorable state of infrastructure. Nigeria is confronted with the problem of immense infrastructure deficit which adversely affect national income, cost of production and distribution of goods and services, reduces Foreign Direct Investment(FDI), and result in poverty, unemployment, frequent youth unrest and fall in the general living standards.2 The poor state of infrastructure assets in the country is traceable primarily to the neglect by government and poor maintenance during the transition period from military rule to civilian administration. In an attempt to recover from the infrastructure decay, privatization was commenced in the late 90s through to the 21st century. Yet, there was no commendable improvements as the quality of public services dropped continuously and most of the enterprises were eventually wounded up as a result of corruption, poor maintenance and lack of skilled expertise.3 Furthermore, as a result of budget deficit caused by contraction in fiscal space, and continuous increase in demand for public services which correlates with population growth and rural-urban migration, public financing cannot facilitate bridging of the infrastructure gap. Also, having realized the success of Public Private Partnership (PPP) in other climes, government adopted PPP in 2005 to aid transition of the state of national infrastructure through private involvement in infrastructure financing. Unfortunately, for well over one decade of adopting PPP, Nigeria has not witnessed any commendable changes in her infrastructure assets. The poor performance of PPP in country has been traced to several factors including corruption, lack of transparency, and undue political interference. Central to the factors is the problem of regulatory deficit.4 Consequently, this study will examine the Nigerian PPP legal and regulatory framework to ascertain the problems responsible for the inability of the infrastructure financing technique to facilitate sustainable development through successful infrastructure projects. / Dissertation (LLM)--University of Pretoria, 2014 / gm2015 / Centre for Human Rights / LLM / Unrestricted
70

Water in the Glass

Draper, Natalie R. 13 July 2009 (has links)
No description available.

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