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Utvecklingen av satellitbaserad positionsbestämning gör det idag befogat att begära låga osäkerheter med GNSS. Det är idag möjligt att uppnå osäkerheter kring centimetern. Bäst mätosäkerhet ger relativ mätning som sker med stöd av antingen enkelstations- eller nätverks-RTK. I Sverige erbjuder Lantmäteriet med sitt SWEPOS ett tätt referensnätverk som förser användaren med korrektionsdata oavsett position inom Sveriges gränser. Dock är det inte alla länder som kan erbjuda denna positionstjänst. Geografiskt stora länder har mycket svårt att skapa ett referensnät, det skulle betyda flera tusen stationer och gör det till en ekonomisk fråga. Det är bl.a. ur den synpunkten andra metoder har växt fram. En av dessa är Precise Point Positioning (PPP). Enligt G. Hedling (personlig kommunikation, 18 mars 2015) har PPP fått en väl etablering inom jordbruket samt på maritima gruv- och oljeplattformar. Metoden är lämplig vid stora öppna ytor och när avståndet till närmsta referensstation är stor. PPP använder sig av absolut positionering och kan mäta både statiskt och kinematiskt och resultat kan fås i realtid och genom efterberäkning. Det ligger i Lantmäteriets intresse att testa kinematisk PPP i Sverige och den här studien testar kinematisk PPP i realtid med programvaran BNC 2.11 och med korrektioner från International GPS Service (IGS). Enligt Bisnath & Gao (2009) erhålls decimeterosäkerhet med kinematisk PPP och för att bestämma dess tillförlitlighet har i den här studien koordinatavvikelse beräknats mellan BNC och enkelstations-RTK med stöd från SWEPOS. Koordinaterna från enkelstations-RTK har vid testerna angivits som de sanna koordinaterna, genom ett statiskt test har det undersökts om det är motiverat. Utifrån den statiska mätningen har även intialiseringstiden kunnat utredas, alltså den tid det tar för PPP att konvergera. Efterberäkningstjänsten CSRS-PPP har också testats och jämförts mot kända koordinater vid den statiska mätningen.Studien visar att efter närmare en timmes observation avviker PPP under 2 dm i plan mot enkelstations-RTK. Den visar också att 15-30 minuters konvergeringstid är nödvändig för att erhålla osäkerheter på några decimeter. Några av de faktorer som påverkar resultatet är bl.a. jonosfärstörning. högt PDOP-värde och antal processerade satelliter i mjukvarorna, hur mycket är svårt att säga. Vid en tappad signal krävs en ny omintialisering på flera tiotals minuter. Studien visar också att det är lämpligt att använda enkelstations-RTK som sanning. Vid den statiska mätningen avviker enkelstations-RTK kring centimetern mot den kända punktens koordinater, vilket anses godtagbart. CSRS-PPP uppvisar bra resultat och är inte mycket sämre än det resultat enkelstations-RTK redovisar. / Today it´s possible to achieve low uncertainties when surveying with GNSS. You can expect uncertainties around centimeter-level. The best results are achieved when using relative-surveying with corrections from single-station- or network-RTK. The Swedish mapping, cadastral and land registration authority (Lantmäteriet) is providing a well-developed network of reference stations. The network, called SWEPOS, offers corrections for its users independent of position within the Swedish borders. Far from all nations has the ability or the financial resources to create such an expanded network. Instead, other methods for satellite surveying have been developed, including Precise Point Positioning (PPP). According to G. Hedling (personal communication, 18 march 2015) PPP is well-established in the agriculture and in the maritime mining- and oil-industry. The method is suitable in open areas and it is independently of nearby reference stations. PPP is using what’s called absolute-surveying. The surveying is performed either kinematic or static and the results can be obtained thru post-processing or in real-time. “Lantmäteriet” has interest in testing kinematic PPP in Sweden and for this thesis kinematic PPP in real-time is tested with BNC 2.11 software and corrections is given from the International GPS Service (IGS). According to Bisnath & Gao (2009) it is possible to achieve uncertainties in decimeter-level with kinematic PPP. To determine the reliability of PPP the deviation has been calculated against single-station-RTK. The single-station-RTK coordinates have in this study been used as the “truth” and in an additional test using static measurements it has been investigated if that’s correct. From the static test the initialization time for PPP as well as the quality of the post-processing service CSRS-PPP has been studied.The results show that after nearly an hour of observation the deviation between PPP and single-station-RTK are below 2 dm for the level-coordinates. The initialization time of 15-30 minutes is necessary to achieve uncertainties of a few decimeters. Elements that are affecting the results are disturbance in the ionosphere, high PDOP and number of processed satellites in the software. In which extent it’s not possible to determine. When the signal is lost between rover and satellites a re-initialization of 15-30 minutes is needed. It also shows that it is reasonable to use single-station-RTK as the “truth”. Single-station-RTK deviates a proximately one centimeter in relation to known coordinates. The post-processing service CSRS-PPP gives remarkably good results not far from what single-station-RTK offers.

Asymmetric digital subscriber line (ADSL) is a broadband access technology capable of delivering large bandwidth over existing copper telephone line infrastructure. This research aims at characterizing and analyzing TCP/IP performance in presence of a new protocol stack (TCP/IP over PPP and ATM) being promoted for one of the ADSL network architectures. Using extensive simulations, we verify the adverse effects of asymmetric links on the performance of TCP and additional throughput degradation caused by the overhead at the AAL5- ATM layers. This study involves unidirectional as well as bi-directional data transfer using different traffic mixes including bursty and non-bursty types of traffic. Bi-directional data transfer over asymmetric links results in ACK compression wherein TCP acknowledgements (ACKs) get bunched together behind larger data packets, further exacerbating the effect of asymmetry on TCP performance. By implementing the simulation model for PPP encapsulation over AAL5, we characterize its effect in terms of throughput degradation and excessive delay. We quantify the improvement in the throughput obtained by delaying the TCP ACKs and by TCP/IP header compression. These techniques being effective for unidirectional traffic over asymmetric links, however, do not prove as effective when ATM enters the scenario or in presence of bi-directional data transfer. Further, we implemented a simulation model of the Smart ACK Dropper (SAD), a technique to regulate the flow of TCP ACKs. Considerable improvement in performance especially in the presence of unidirectional data transfer is achieved using the SAD technique. Although the improvement is to a lesser extent in the presence of bi-directional data traffic, SAD helps the network in quickly recovering from the impact of ACK compression. We also propose and implement certain customized queuing/scheduling and policing mechanisms to enable differentiated servicing of TCP ACKs and data packets, and mitigate the effect of ACK compression. While providing considerable TCP performance improvement in presence of SAD, custom queuing also allows fair sharing of bandwidth between TCP flows, unlike priority queuing, which starves the low priority flow. The committed access rate (CAR)policing scheme provides considerable performance improvement when used with SAD, and is especially useful when TCP ACKs compete with bursty data traffic over the slower upstream. / Master of Science

Yes

[pt] A PPP (Parcerias Públicos-Privados) tem por objetivo viabilizar projetos de infraestrutura através da concessão de algum tipo de apoio governamental com garantias ou aportes de recursos, visando mitigar o risco do projeto tornando-o mais atrativo para o setor privado. Este estudo utiliza a metodologia de opções reais para modelar o impacto dos incentivos do governo no contrato de concessão sobre o valor do projeto. A análise de projeto sob esta ótica considera as flexibilidades especificas do projeto em estudo, tornando o projeto viável que antes poderia não ser atrativo ao investidor privado, em função das grandes incertezas existentes sobre a demanda prevista. Será realizado um estudo de caso baseado na Manifestação de Interesse da Iniciativa Privada – MIP 03/2012, que tem por objetivo o início da licitação de concessão ou PPP para a implantação, manutenção, e operação do serviço de transporte metroviário da LINHA 3 do Estado do Rio de Janeiro, entre os Municípios de Niterói e São Gonçalo. / [en] The PPP (Public-Private Partnership) aims to facilitate infrastructure projects by granting some form of government support with guarantees or capital injections, to mitigate project risk by making it more attractive to the private sector. In this study, we will use the methodology of Real Options to model the impact of government incentives in the contract of concession on the value of the project. The analysis of the project by this point of view considers the specific flexibilities of the project being studied, making the project feasible which previously might not be attractive to the private investor, according to the major uncertainties about the expected demand. It will be done a study case based in the Expression of Interest from Private Initiative - MIP 03/2012 that has as objective the start of the bidding for concession or PPP for deployment, maintenance and operation of the Subway Systems service from Line 3 of Rio de Janeiro State, between the cities of Niterói and São Gonçalo.

<p>For every operating condition of an internal combustion engine there exists an optimal spark timing, called maximum brake torque (MBT), which maximises the output torque and the efficiency of the engine. Traditionally MBT timing is implemented as an open-loop control where the ignition timing is found by using a combination of static lookup tables and sensor information. With a direct closed-loop control from the combustion process the performance of internal combustion engines could be improved. The thesis investigates if it is possible to estimate the MBT timing from the ionization current for every operating condition of a spark ignited engine where the operating conditions are defined by the engine parameters lambda, internal exhaust gas recirculation, engine load, engine speed and spark advance.</p><p>First an investigation of how much loss of torque an error from the MBT position corresponds to is made. Then the influence of the engine parameters on the shape of the ionization current was studied. Last different peak pressure position (PPP) estimating algorithms are presented and a new technique is developed where an engine operating point dependant part of the ionization current is used depending on the current operating condition of the engine. Two of the presented PPP estimating algorithms are then complemented with this technique and the results look promising.</p>

For every operating condition of an internal combustion engine there exists an optimal spark timing, called maximum brake torque (MBT), which maximises the output torque and the efficiency of the engine. Traditionally MBT timing is implemented as an open-loop control where the ignition timing is found by using a combination of static lookup tables and sensor information. With a direct closed-loop control from the combustion process the performance of internal combustion engines could be improved. The thesis investigates if it is possible to estimate the MBT timing from the ionization current for every operating condition of a spark ignited engine where the operating conditions are defined by the engine parameters lambda, internal exhaust gas recirculation, engine load, engine speed and spark advance. First an investigation of how much loss of torque an error from the MBT position corresponds to is made. Then the influence of the engine parameters on the shape of the ionization current was studied. Last different peak pressure position (PPP) estimating algorithms are presented and a new technique is developed where an engine operating point dependant part of the ionization current is used depending on the current operating condition of the engine. Two of the presented PPP estimating algorithms are then complemented with this technique and the results look promising.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-01-11T11:43:24Z No. of bitstreams: 1 anamariamachadofranckincerti.pdf: 1380702 bytes, checksum: 2565bfd7905d7af3dcd92049d3b2e67a (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2017-01-31T11:19:26Z (GMT) No. of bitstreams: 1 anamariamachadofranckincerti.pdf: 1380702 bytes, checksum: 2565bfd7905d7af3dcd92049d3b2e67a (MD5) / Made available in DSpace on 2017-01-31T11:19:26Z (GMT). No. of bitstreams: 1 anamariamachadofranckincerti.pdf: 1380702 bytes, checksum: 2565bfd7905d7af3dcd92049d3b2e67a (MD5) Previous issue date: 2016-02-29 / Esta dissertação, desenvolvida no Programa de Pós-graduação Profissional em Gestão e Avaliação da Educação Pública da Universidade Federal de Juiz de Fora, é o resultado de uma pesquisa que investigou as ações desenvolvidas pela equipe gestora da Escola Estadual das Seringueiras (nome fictício) do município de Carauari, Amazonas. O objetivo principal foi analisar como a equipe gestora da Escola Estadual das Seringueiras, com um número reduzido de integrantes, organiza suas atividades e planeja suas ações no âmbito da gestão administrativa e pedagógica no período compreendido entre os anos de 2011 e 2014. A metodologia adotada neste trabalho consistiu-se em uma pesquisa qualitativa, por meio de um estudo de caso, onde se buscou analisar fontes documentais, entrevistas e questionários, fundamentação teórica nos dispositivos legal nacional e estadual, como também, em pressupostos de autores dentre os quais se destacam Heloiza Luck (2009), Vieira (2008), Canário (1997). No primeiro capítulo realizou-se uma contextualização da Rede Estadual de Educação do Amazonas. Buscou-se identificar as práticas de trabalho relativas ao contexto administrativo, pedagógico e funcionamento da escola. Ao mesmo tempo realizou-se o levantado do perfil da equipe gestora, do corpo docente e discente e aprofundou-se na análise do PPP e dos índices de proficiência alcançados nas avaliações externas. O segundo capítulo apresenta uma releitura do conceito de gestão democrática e participativa embasados nas dimensões de Luck de forma que norteiam a dimensão escolar no que se refere ao trabalho e as tomadas de decisões desta equipe, o que forneceu suporte para avaliar como esta equipe gestora cumpre sua agenda de trabalho escolar,como se organiza e planeja suas ações mesmo possuindo uma equipe gestora mínima, pouca participação da comunidade escolar, alta rotatividade de profissionais e, principalmente, como esta gerencia o seu processo educacional tendo um PPP desatualizado e não possuindo um Conselho Escolar. Neste contexto investigativo observou-se que mesmo possuindo problemas nas áreas pedagógico/administrativa, esta escola alcançou índices satisfatórios nas avaliações externas no IDEB e no SADEAM, se firmando na comunidade como uma escola de valor que busca a qualidade no processo educativo. O último capítulo apresenta uma proposta de intervenção para o aprimoramento das ações a serem realizada no contexto escolar de forma que possam minimizar os entraves encontrados no fazer pedagógico e administrativo na escola pesquisada e, também, direciona encaminhamentos que visam a reelaboração do PPP, criação do Conselho Escolar e a elaboração de uma agenda de eventos como forma de fortalecimento do processo de gestão democrática e participativa nesta escola. / This dissertation, developed at the Graduate Program in Professional Management and Public Education Evaluation of the Federal University of Juiz de Fora, is the result of a research that investigated the developed actions by the management team at State School of Seringueiras (fictitious name), in Carauari town, Amazonas. The main objective was analyze how the management team at State School of Seringueiras, with a reduced number of members, organize their activities and plan their actions in the framework of a administrative management and pedagogical for the period from 2011 to 2014. The adopted methodology in this study consists of a qualitative research through a case study, where was analyzed documentary sources, interview and questionnaires, theoretical foundations in national and state legal devices, but also in, preconditions of authors among which stand out Heloiza Luck (2009), Vieira (2008), Canário (1997). In the first chapter there is a contextualization of State Schooling in Amazonas. We sought to identify work practices relating to administrative context, pedagogical and the proper functioning of the school. At the same time management team, faculty and students survey profile was developed, and deepened in analysis about PPP and proficiency index reached in the external evaluations. The second chapter presents a re-reading of democratic and participative management concept grounded in Luck dimensions in a way that guide the educational dimension regarding the work and decisions making taken by the team, what provided support to evaluate how this management team fulfills their school's words agenda, how is organized and planed their actions even though with a minimum management team, very little involvement of school community, professional's hight turnover and, mainly, how manage educational process having a outdated PPP and having no School Council. In this investigative context was noted that even having problems in administrative/pedagogical area, this school reached satisfactory indices in external evaluations at IDEB and SADEAM, staying firm in community as a value school that search for quality in education process. The last chapter presents a proposal for an intervention in actions enhancement to be held in a school context in a way that minimize the barriers found in do pedagogical and administrative at the research school and, also, directs referrals which aim at the reelaboration of PPP, creation of a School Council and the elaboration of an events agenda as a fortification way in the democratic and participative management in the process of school.

Diploma thesis deals with the implementation of the public private partnership concept in Czech Republic. Its primary aim is to highlight risks of the PPP concept. Thesis describes theoretical and practical risks of the concept and concludes that the threat of risks is much more significant when the PPP concept is implemented in insufficiently suitable environment. In the practical part the thesis finds an answer to the question whether the PPP concept is suitable for implementation in the Czech Republic. By analyzing the legal and institutional environment and factors such as public procurement, corruption, transparency and public finances, the thesis demonstrates that under current conditions the implementation of the PPP concept is not suitable in Czech Republic. Conclusions are confirmed by analysis of PPP concept implementation. Finally, the thesis pronounces recommendations about the future application of the PPP concept in Czech Republic.