Mέσα στα πλαίσια της διπλωματικής αυτής προσεγγίστηκε μια νεα τεχνική για τη διάγνωση σφαλμάτων τετράχρονης μηχανής. Αυτή η τεχνική βασίζεται πάνω σε πιεζοηλεκτρικά υλικά και αισθητήρες και υλοποιεί την ικανότητά τους να μετατρέπουν μηχανική τάση ή πίεση σε ηλεκτρική τάση. Αυτοί οι αισθητήρες τοποθετούνται πάνω στη μηχανή και το παραγόμενο σήμα δειγματοληπτείται και περνά απο μια επεξεργασία με σκοπό την αποκόμιση μιας διάγνωσης για την κατάσταση στην οποία βρίσκεται η μηχανή αλλά και για τη συνεχή παρακολούθηση αυτής. Κατα την εκπόνηση της διπλωματικής, διαφορετικές τεχνικές για την εύρεση σφαλμάτων μηχανής χρησιμοποιούνται και προσεγγίζονται διαφορετικοί αλγόριθμοι δειγματοληψίας και επεξεργασίας με σκοπό να εξασφαλισθεί ο πιο αποδοτικός για την εφαρμογή αυτή. Ακόμα, η χρήση και οι ικανότητες των σύγχρονων ενσωματωμένων συστημάτων ερευνώνται και πιο συγκεκριμμένα του μικροεπεξεργαστή της Analog, τον ADuC7020, πάνω στον οποίο βασίζεται και η διπλωματική αυτή, για την υλοποίηση της συσκευής εντοπισμού σφαλμάτων και τον προγραμματισμό αυτής. Κατα την φάση της εξομοίωσης, ένα ημιτονοειδές σήμα χρησιμοποιήθηκε για την προσέγγιση του ήχου της μηχανής. Στο στάδιο της επεξεργασίας του σήματος χρησιμοποιήθηκε ψηφιακό φίλτρο πεπερασμένης κρουστικής απόκρισης (FIR) και τροποποιημένος αλγόριθμος DFT για τη δειγματοληψία και την επεξεργασία του ψηφικοποιημένου σήματος αλλά και για την αναγνώριση της συχνότητας. Πιο συγκεκριμένα, υλοποιήθηκε ο βελτιστοποιημένος αλγόριθμος Goertzel ο οποίος προτιμήθηκε για την επίτευξη μεγαλύτερων ταχυτήτων. Τέλος, υλοποιήθηκε και η τεχνική της υπερδειγματοληψίας για την επίτευξη μεγαλύτερης ακρίβειας. Ο προγραμματισμός έγινε σε γλώσσα C και το λογισμικό που χρησιμοποιήθηκε ήταν το μVision4 της Keil. / At the present thesis we examine the automatic fault detection in petrol engines using piezoelectric sensors in embedded systems.

Made available in DSpace on 2015-03-13T17:08:28Z (GMT). No. of bitstreams: 1 1-100.pdf: 4856681 bytes, checksum: 9a9a288a1ab8a2fbbf25e68815d417ca (MD5) Previous issue date: 2009-10-19 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The study area consist in high sensitivity environments located on the northern coast of Rio Grande do Norte, Northeast Brazil. The barrier island are the main geomorphological features on the coastal landscape, being naturally instable and surrounded by industrial activities like oil fields, salt industry, shrimp farms and urban areas sometimes installed parallel to the coast, combined with coast engineering interventions. High energy hydrodynamic process are responsible for the morphological instability of the coast. The study was based on remote sensing data obtained between 1954 and 2007 which consist in orbital images from Landsat, CBERS and Ikonos satellites and aerial photos. With all data integrated on GIS environment it was possible to update thematic maps of geology, geomorphology, vegetation, soil and landuse and development of multitemporal maps pointing areas with erosion and depositions of sediments, defining the critical erosion process on this region. The bigger morphological changes are related to changes on wind patterns during the year, terrestrial and sea breezes during the day, with spits and barrier island migration, opening and closing of channels like the one parallel to the coast on the area of Serra and Macau oil fields. These factors combined with the significant reduction on sediment budgets due to the loss of natural spaces to sediment reworking contribute to the low resilience which tends to be growing on the area of Serra and Macau oil fields. In front of such scenery a detailed monitoring was done in order to find technological possibilities for coastal restoration. A pilot area was defined to start the project of mangrove restore together with beach nourishment in order to minimize the effect of the erosion caused by the channel parallel to the coast, contributing to stabilize the northeast channel as the main one. It s expected that such methodology will aid the coastal environments restoration and the balance between industrial activities and coastal erosion / A ?rea de estudo est? inserida no litoral setentrional do Rio Grande do Norte, situado no extremo NE do Brasil, apresenta ambientes de alta sensibilidade ambiental tendo como principal caracter?stica na geomorfologia do litoral as ilhas barreiras, ambientes fr?geis e ef?meros circundado por atividades antr?picas como os campos petrol?feros, a atividade salineira, de carcinicultura e ?reas urbanas. A regi?o ? caracterizada por processos hidrodin?micos de alta energia respons?veis pela intensa a??o da din?mica costeira. O estudo foi realizado tendo como base dados entre 1954 e 2007 obtidos com o uso de sensores orbitais ?pticos: Landsat, CBERS, Ikonos e fotografias a?reas, validadas por fotografias a?reas de pequeno formato adquiridas ao longo dos anos. Com todos os dados integrados em ambiente SIG, foi atualizado o mapa Geol?gico, Geomorfol?gico, Vegeta??o, Pedol?gico, de Uso e Ocupa??o do Solo do BDAG e confeccionado os mapas multitemporais, apontando como resultado o mapeamento das ?reas de acres??o e de eros?o de sedimentos, caracterizando o processo de eros?o como cr?tico na ?rea do estudo. As altera??es morfol?gicas de maior magnitude observadas est?o relacionadas ? modifica??o no padr?o anual de ventos, destacando-se as brisas marinhas e terrestres na circula??o di?ria, com migra??o dos spits e das ilhas barreiras dominadas por mar?, levando a abertura e fechamento de canais de mar?, em especial do canal paralelo ? linha de costa, pr?ximo aos campos petrol?feros, proporciona uma redu??o significativa de aporte de sedimento na zona costeira, devido ? indisponibilidade de espa?o natural para o retrabalhamento do sedimento. Estes fatores combinados contribuem para a baixa resili?ncia1 que tende a ser crescente na ?rea dos Campos de Serra e Macau. Dentro deste cen?rio, foi realizado um levantamento minucioso buscando alternativas tecnol?gicas de restaura??o costeira. Enfim, por se tratar de ambientes predominantemente de ilhas barreiras, foi mapeada uma ?rea piloto, onde ? sugerida a instala??o do projeto de restaura??o dos ecossistemas de manguezais, combinada com restaura??o ecol?gica de engordamento de praia, buscando minimizar o efeito do Canal paralelo ? linha de costa, corroborando para a estabiliza??o do canal noroeste como o canal preferencial. Espera-se com esta estrat?gia metodol?gica contribuir para a restaura??o de ambientes costeiros e o conv?vio da atividade com a problem?tica da eros?o costeira

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-12-15T16:48:52Z No. of bitstreams: 1 AndreRodriguesFabricio_DISSERT.pdf: 2394615 bytes, checksum: dba8eaca128da0e2f6646fa6d4ff0f03 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2015-12-18T21:39:39Z (GMT) No. of bitstreams: 1 AndreRodriguesFabricio_DISSERT.pdf: 2394615 bytes, checksum: dba8eaca128da0e2f6646fa6d4ff0f03 (MD5) / Made available in DSpace on 2015-12-18T21:39:39Z (GMT). No. of bitstreams: 1 AndreRodriguesFabricio_DISSERT.pdf: 2394615 bytes, checksum: dba8eaca128da0e2f6646fa6d4ff0f03 (MD5) Previous issue date: 2014-09-11 / O Estado brasileiro desenvolveu a pol?tica de Conte?do Local como a??o regulat?ria inserida na din?mica do setor petrol?fero para, garantindo a prefer?ncia ? ind?stria nacional, conseguir desenvolv?-la dentro do seu territ?rio. Com base nessa realidade, o presente trabalho se prop?e a analisar a pol?tica de Conte?do Local perante o objetivo constitucional de desenvolvimento conforme disposto na Constitui??o Federal de 1988. Para tanto, aplicar-se-? o m?todo hipot?tico-dedutivo, para, indicando a Pol?tica de Conte?do Local como meio hipot?tico de a??o estatal que busca o desenvolvimento, possa ser criticada atrav?s das lacunas nela existentes, algo a ser tratado atrav?s do m?todo dial?tico de investiga??o, objetivando a formula??o de uma impress?o te?rica sobre a pol?tica. Foi obtido como resultado a inadequa??o estrutural da pol?tica de Conte?do Local perante o objetivo constitucional de desenvolvimento, pela limita??o do seu potencial realizado pela falta de planejamento e legitima??o por parte do Estado na formula??o de uma pol?tica p?blica estatal t?o importante, apesar de ter sido averiguada que axiologicamente a fundamenta??o existente para sua sustenta??o jur?dica ? perfeita, sendo poss?vel de ser encontrada por todo o teor do texto constitucional. Conclui-se, que apesar de sua formula??o inadequada, a pol?tica de Conte?do Local tem conseguido dentro da estrutura criada pela Ag?ncia Nacional do Petr?leo, realizar um papel importante para ind?stria nacional, algo que deve ser incrementado, algo somente feito atrav?s de uma reestrutura??o da sua formata??o com a consequente distribui??o de compet?ncias e de metas a serem cumpridas pelos ?rg?os estatais em prol da melhoria da qualidade de vida, presente e futura, nos diversos ?mbitos territoriais da sociedade brasileira. / On the petroleum industry, the State developed the Local Content police as a regulatory action to guarantee the preference of the national supply industry. Observing that, this paper will analyze the Local Content police aware of the constitutional goal of development as wright in the Constitui??o Federal de 1988. For it, will be used the hypothetical-deductive method for identifying the Local Content police as State strategy of development turn it in the object of critics in a dialectic way of thinking to in the final, present a conclusion about the police. As result was saw that the existent structure of the police at Brazil is inefficient, claiming for a rebuilt. For conclusion, is said that because of the inadequate construction of the Local Content police created inside of the Ag?ncia Nacional do Petr?leo ? ANP, the efficiency of the full potential of the police is been stopped, something that can be only corrected although a re-make of the police

Made available in DSpace on 2014-12-17T15:14:53Z (GMT). No. of bitstreams: 1 MichelliSO_TESE.pdf: 582340 bytes, checksum: ab3d5e44a55d3fc0f68bbe728403a091 (MD5) Previous issue date: 2011-07-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Oil prospecting is one of most complex and important features of oil industry Direct prospecting methods like drilling well logs are very expensive, in consequence indirect methods are preferred. Among the indirect prospecting techniques the seismic imaging is a relevant method. Seismic method is based on artificial seismic waves that are generated, go through the geologic medium suffering diffraction and reflexion and return to the surface where they are recorded and analyzed to construct seismograms. However, the seismogram contains not only actual geologic information, but also noise, and one of the main components of the noise is the ground roll. Noise attenuation is essential for a good geologic interpretation of the seismogram. It is common to study seismograms by using time-frequency transformations that map the seismic signal into a frequency space where it is easier to remove or attenuate noise. After that, data is reconstructed in the original space in such a way that geologic structures are shown in more detail. In addition, the curvelet transform is a new and effective spectral transformation that have been used in the analysis of complex data. In this work, we employ the curvelet transform to represent geologic data using basis functions that are directional in space. This particular basis can represent more effectively two dimensional objects with contours and lines. The curvelet analysis maps real space into frequencies scales and angular sectors in such way that we can distinguish in detail the sub-spaces where is the noise and remove the coefficients corresponding to the undesired data. In this work we develop and apply the denoising analysis to remove the ground roll of seismograms. We apply this technique to a artificial seismogram and to a real one. In both cases we obtain a good noise attenuation / A explora?c ao petrol?ıfera ?e uma das atividades mais complexas e de dif?ıcil execu?c ao na ind?ustria do petr?oleo e tamb?em ?e umas de suas tarefas mais importantes. Devido aos elevados custos dos m?etodos diretos usados para localiza?c ao e avalia?c ao das jazidas de petr?oleo, tais como a perfura?c ao de po?cos explorat?orios para a medi?c ao de propriedades in situ, m?etodos indiretos s ao utilizados com esta finalidade. O principal destes m?etodos ?e o da sondagem s?ısmica. Neste processo de explora?c ao, ondas s?ısmicas geradas por explos oes ou por vibradores, propagam-se no subsolo e ap?os serem espalhadas pelas heterogeneidades das estruturas geol?ogicas retornam `a superf?ıcie onde s ao coletadas para constru?c ao dos sismogramas ou imagens s?ısmicas. No entanto, os sismogramas cont em, al?em das informa?c oes sobre as estruturas do subsolo, uma grande quantidade de ru?ıdo, sendo o principal deles o chamado ru?ıdo de rolamento superficial ( ground roll ou ondas de Rayleigh). A atenua?c ao desses ru?ıdos ?e essencial para uma boa interpreta?c ao dos dados e sinais s?ısmicos. A an?alise dos sismogramas pode ser feita utilizando-se diversos tipos de transformadas espectrais que levam o sinal s?ısmico para o espa?co das frequ encias (Transformada de Fourier) ou para o espa?co tempo-frequ encia (Transformada Wavelet), onde costuma ser mais simples atenuar ou remover os ru?ıdos de uma forma cir?urgica. Isto permite que, ao levar o sinal s?ısmico de volta ao espa?co original, o sinal represente apenas as informa?c oes sobre as estruturas geol?ogicas de interesse. Por outro lado, a transformada curvelet ?e uma nova e efetiva transformada espectral que tem sido largamente usada no estudo e representa?c ao de dados complexos. Nessa an?alise, as fun?c oes ou sinais estudados s ao expressados em termos de fun?c oes de base com car?ater direcional que permitem representar, mais efetivamente que outras an?alises, imagens e sinais com descontinuidades superficiais ou ao longo de curvas. A an?alise curvelet mapeia o espa?co das frequ encias em diferentes escalas e em setores angulares, de modo que se pode identificar as regi oes deste espa?co dominadas pelo ru?ıdo presente no sinal. Remover os coeficientes referentes a essas regi oes ?e remover o ru?ıdo do sinal. Assim, nesta tese implementamos e aplicamos a an?alise curvelet para remover o ru?ıdo de rolamento superficial dos sinais s?ısmicos. Testamos este m?etodo tanto para um sismograma sint?etico quanto para um sismograma real e obtivemos uma ?otima atenua?c ao do ru?ıdo em ambos os casos. Comparamos este m?etodo com os m?etodos empregados anteriormente e discutimos poss?ıveis aplica?c oes desta t?ecnica a outros problemas

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T23:07:12Z No. of bitstreams: 1 JorgeLuisDeOliveiraPintoFilho_TESE.pdf: 8152297 bytes, checksum: 669cfdc30d92d542a303ce3d3de6f61c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-14T00:36:04Z (GMT) No. of bitstreams: 1 JorgeLuisDeOliveiraPintoFilho_TESE.pdf: 8152297 bytes, checksum: 669cfdc30d92d542a303ce3d3de6f61c (MD5) / Made available in DSpace on 2017-03-14T00:36:04Z (GMT). No. of bitstreams: 1 JorgeLuisDeOliveiraPintoFilho_TESE.pdf: 8152297 bytes, checksum: 669cfdc30d92d542a303ce3d3de6f61c (MD5) Previous issue date: 2016-08-29 / A Bacia Hidrogr?fica do rio Apodi-Mossor? ? BHRAM, localiza-se na Regi?o Oeste do Estado do Rio Grande do Norte ? RN, onde seu baixo curso contempla uma consider?vel interven??o antr?pica, relacionada com a explora??o de petr?leo e g?s, minera??o de areia, explora??o de calc?rio, atividade salineira, com?rcio e servi?os, urbaniza??o, tr?fego de ve?culos, transporte de cargas, constru??o civil, turismo, fruticultura irrigada, carcinicultura, pesca, pecu?ria e gera??o de energia e?lica. A partir dessa press?o antr?pica esta tese buscou comparar os indicadores socioecon?micos e ambientais dos munic?pios do baixo curso dessa bacia, bem como avaliar as condi??es socioecon?micos e ambientais da ?rea do Campo Petrol?fero Canto do Amaro ? CPCA/RN. Como procedimentos metodol?gicos adotaram-se: aplica??o do gr?fico de radar para mensurar os indicadores socioecon?micos e ambientais dos munic?pios do baixo curso da BHRAM/RN; percep??o ambiental das condi??es socioecon?micas e ambientais das comunidades rurais da ?rea do CPCA/RN; monitoramento dos teores de metais pesados em diversos ambientes na ?rea; avalia??o do sistema de abastecimento de ?gua para consumo humano na regi?o investigada; identifica??o dos impactos ambientais no CPCA/RN atrav?s do sistema Press?o-Estado-Impacto-Resposta e; proposi??o de a??es de gest?o ambiental para atenuar a problem?tica pesquisada. Constatou-se que no baixo curso da bacia existe uma concentra??o dos melhores ?ndices na dimens?o econ?mica, enquanto a dimens?o ambiental encontra-se em uma situa??o intermedi?ria e, a dimens?o social ainda possui valores inferiores. Evidenciou-se que na ?rea do CPCA/RN a popula??o local tem restri??es socioecon?micas e vive em comunidades rurais com defici?ncias nos componentes de saneamento ambiental. Determinou-se que os ambientes relacionados com a ind?stria do petr?leo foram os que comportaram-se com maiores n?veis m?dios dos metais pesados: Cu, Cr, Fe (em po?os ativos), Ni (po?os ativos) e, Pb (res?duos s?lidos). Entretanto, tr?s outros tipos de usos dos solos apresentaram maiores valores dos metais pesados: Cd (?reas naturais), Mn (rio do Carmo) e Zn (Carcinicultura); entrentanto, esses n?veis s?o relativamente baixos quando comparados aos obtidos em solos de interfer?ncia de tr?fego de ve?culos, atividade petroqu?mica e aos valores de refer?ncia de qualidade. Verificou-se fragilidades no abastecimento de ?gua para consumo humano nos aspectos de quantidade de ?gua e qualidade de ?gua, com valores abaixo do permitido para Oxig?nio Dissolvido e com presen?a de ?leo e graxas. Observou-se que o CPCA/RN oportuniza a gera??o de emprego, renda, royalties, energia, combust?vel e proje??o da regi?o no cen?rio nacional. Entretanto, essa cadeia produtiva representa grandes riscos e vulnerabilidades socioambientais atrav?s dos seguintes aspectos e impactos: gera??o de emiss?es atmosf?ricas, gera??o de res?duos semiss?lidos (lama e cascalho), gera??o de res?duos s?lidos, gera??o de efluentes l?quidos, gera??o de ru?dos, polui??o h?drica, polui??o do solo, polui??o sonora, polui??o atmosf?rica, polui??o visual, supress?o vegetal, processos erosivos, interfer?ncia na flora local, interfer?ncia na fauna local, altera??o da estabilidade dos ecossistemas, altera??o da din?mica de uso do solo, riscos ? sa?de dos trabalhadores, press?o nas comunidades locais, interfer?ncias nas atividades tradicionais e, press?o na infraestrutura de servi?os p?blicos. A ?rea do CPCA/RN tem implica??es socioecon?micas e ambientais que comprometem a manuten??o da qualidade do baixo curso da BHRAM/RN, sendo requeridas diretrizes de gest?o ambiental para atenuar a problem?tica. / The Basin Apodi-Mossor? River - BHRAM, located in the Western Region of the State of Rio Grande do Norte - RN, where its low course includes a considerable human intervention, related to oil and gas, sand mining, limestone exploration, sea salt industry, trade and services, urbanization, vehicle traffic, cargo transportation, construction, tourism, irrigated fruit, shrimp farming, fishing, livestock and wind power generation. From this anthropic pressure this thesis aimed to compare the socio-economic and environmental indicators of the municipalities of the lower course of this basin, as well as assessing the socioeconomic and environmental conditions of the Canto do Amaro Oil Field area - CPCA / RN. The following methodological procedures were adopted: radar chart application to measure the socioeconomic and environmental indicators of the municipalities of the lower course of BHRAM / RN; environmental perception of socioeconomic and environmental conditions of rural communities in the area of the CPCA / RN; monitoring of heavy metal content in several environments in the area; evaluation of the water supply for human consumption in the investigated region; identification of environmental impacts in the CPCA / RN through the Pressure-State-Impact-Response system and; proposition of environmental management actions to mitigate the researched problematic. It was found that there is a concentration of the best rates in the economic dimension in the lower course of the basin, while the environmental dimension is in an intermediate situation, with the social dimension still shows lower values. It was demonstrated that the local population in the area of CPCA / RN has socio-economic constraints and lives in rural communities with deficiencies in environmental sanitation components. It was determined that the settings related to the oil industry displayed the higher average levels of heavy metals: Cu, Cr, Fe (in active wells), Ni (active wells), and Pb (solid wastes). Meanwhile, three other types of land uses showed higher values of heavy metals: Cd (natural areas), Mn (Carmo River) and Zn (Shrimp farms); however, these levels are relatively low when compared to those soils with vehicle traffic interference, with petrochemical activity and to the quality benchmarks. It has been found weaknesses in the water supply for human consumption in the aspects of water quantity and water quality with values below the allowed by the legislation for Dissolved Oxygen and with content of oil and greases. It was observed that the CPCA / RN provides an opportunity to generate employment, income, royalties, energy, fuel and projection of the region on the national scene. However, this chain represents great risks and socioenvironmental vulnerabilities through the following aspects and impacts: generation of atmospheric emissions, generation of semi-solid waste (mud and gravel), solid waste generation, the generation of wastewater, noise generation, water pollution, soil pollution, noise pollution, air pollution, visual pollution, vegetation removal, erosion, interference with local flora, interference with local fauna, changing the stability of ecosystems, changes in land use dynamics, risks to workers' health, pressure on local communities, interference in traditional activities and pressure on public services infrastructure. The area of the CPCA / RN has socioeconomic and environmental implications that affect the maintainance of the quality of the lower course of BHRAM / RN, being required environmental management guidelines to mitigate the problem.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-03T21:15:21Z No. of bitstreams: 1 MauriloGoncalvesBragaJunior_DISSERT.pdf: 8769119 bytes, checksum: e351abbadca543f896ba48254b1921fb (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-07T21:40:50Z (GMT) No. of bitstreams: 1 MauriloGoncalvesBragaJunior_DISSERT.pdf: 8769119 bytes, checksum: e351abbadca543f896ba48254b1921fb (MD5) / Made available in DSpace on 2017-04-07T21:40:50Z (GMT). No. of bitstreams: 1 MauriloGoncalvesBragaJunior_DISSERT.pdf: 8769119 bytes, checksum: e351abbadca543f896ba48254b1921fb (MD5) Previous issue date: 2016-12-16 / A avalia??o do comportamento hidrodin?mico e hidroqu?mico de aqu?feros em ?reas sob a influ?ncia da atividade petrol?fera s?o essenciais para a prote??o e gest?o do recurso h?drico subterr?neo. Neste sentido, s?o analisadas neste trabalho as rela??es entre as cargas hidr?ulicas dos aqu?feros Barreiras-Janda?ra e A?u na ?rea de Fazenda Bel?m, setor oeste da Bacia Potiguar, Estado do Cear?, e suas implica??es na qualidade das ?guas subterr?neas. Foram definidas as superf?cies potenciom?tricas das unidades aqu?feras Barreiras-Jandaira e A?u em diferentes per?odos desde seu estado original, antes da influ?ncia da atividade petrol?fera, at? os dias atuais, bem como identificadas as modifica??es hidroqu?micas nessas unidades ao longo desse per?odo. Foi poss?vel concluir que os aqu?feros A?u e Barreiras-Janda?ra correspondem a sistemas aqu?feros individualizados e sem comunica??o hidr?ulica entre si. Os tipos hidroqu?micos distintos definidos para as ?guas dos dois sistemas aqu?feros ratificam o isolamento hidr?ulico caracterizado, sugerindo a inexist?ncia de mistura de ?guas entre os mesmos, desde seu estado original at? o presente. O estudo constatou ainda um rebaixamento localizado da superf?cie potenciom?trica do Aqu?fero A?u, o que aponta para a necessidade de se propor medidas de controle, mediante o monitoramento cont?nuo dos n?veis d??gua desse aqu?fero e da qualidade de suas ?guas / The evaluation of the hydrodynamic and hydrochemistry behavior of the aquifers in areas under the influence of the oil exploration activity is essential to the protection and management of the groundwater resource. In this sense, were analyzed in this work the relationship between hydraulic loads of aquifers Barreiras-Janda?ra and A?u, in the oil production concession area of Fazenda Bel?m, West sector of the Potiguar Basin, State of Cear?, and its implications on the quality of groundwater. The A?u Aquifer is composed by Units 2 and 3 of A?u Formation, composed predominantly of thick sandstones at the base, with decreasing grain size to the top, with metrics and decimetrics beds of mudstone and silt. On top of the A?u Aquifer occurs a 70 meters thick package of mudstone and silt of Unit 4 of A?u Formation, which covers and seals the Units 2 and 3 of A?u Aquifer, giving a confined character to it. The Aquifer system Barreiras-Janda?ra is represented by sandstones and conglomerates of the Barreiras Formation and Quaternary Sediments, which cover the carbonates of Janda?ra Formation (packstones and wackstones) and expose the groundwater of this Aquifer at atmospheric pressure. The potentiometric surfaces of the two aquifers systems for different periods, since its original state, before the influence of the oil exploration activity, until the present day were set, as well the variations in hydrochemistry of these units, throughout this period and the saturated thickness of the two Aquifer units. With this amount of information is possible to presume that the A?u and Barreiras?Janda?ra aquifers correspond to individual aquifers systems without hydraulic communication with each other. The distinct water chemical classes of the two aquifers confirm the isolation between them indicating the absence of water mix between the two systems, since its original state until the present. The study has identified a local fall in the potentiometric surface of the A?u aquifer, which points to the need to propose measures of control, through the continuous monitoring of water levels of the aquifer and the quality of its waters.

The thesis concerns with measurement of processes of support and maintenance of a specialized information system for petrol stations. It is a system for support of retail sale of fuel and other non-fuel goods. As the main objective of the thesis was selected design of set of metrics for measurement of these processes based on multidimensionality principle. It means that dimensions and indicators are designed separately and a set of recommended metrics is based on their combinations. It is possible to get additional metrics using other combinations. The theoretical basis of the thesis is the ITIL library -- which is an internationally respected standard for IT service management -- and metrics designed in other literature and diploma theses. The designed metrics are adapted for the analyzed environment and service information system, however, they should be usable in other environments as well. Selected metrics were implemented to the service information system and measured in a relatively wide sample of input data. This allowed evaluating usability of the metrics and comparison of the threshold values with the measured ones. The relationship of metrics and service agreements (SLAs) is described in the end of the thesis. Specific metrics suitable to be incorporated to SLA were designed including a real-life example.

This thesis deals with the evaluation of risks of business development proposals ZEVOS a.s. acting on the fuel market. The thesis is divided into three main parts, the first part describes the theoretical knowledge. In this section are shown and described methods of dealing with the internal and external surroundings of the company. In the second part, which deals with the analytical part, the methods used to assess the current situation in the market where the company operates. The third part provides a proposal for the development of business solutions and financial investment return.

Please read the abstract in the section, 00front of this document / Dissertation (MEng (Environmental Engineering))--University of Pretoria, 2008. / Chemical Engineering / MEng / Unrestricted

[pt] Nesta dissertação é desenvolvido um modelo para previsão de curto prazo da demanda mensal de gasolina automotiva no Brasil. A metodologia usada consiste em, a partir de uma análise exploratória dos dados, procurar construir um modelo usando uma estratégia bottom-up, ou seja, parte-se de um modelo simples e processa-se seu refinamento até encontrar um modelo apropriado que mais se adequa à realidade. Partiu-se então de um modelo autoprojetivo indo até uma formulação de Redes Neurais passando por um modelo de regressão dinâmica. Os modelos são então comparados segundo alguns critérios, basicamente no que tange à sua eficiência preditiva. Conclui-se ao final sobre a eficiência de se conjugar modelos estatísticos clássicos (como Box & Jenkins e Regressão Dinâmica) com as chamadas Redes Neurais que, por sua vez, propiciaram resultados muito bons em relação à otimização das previsões. Isto é altamente desejável na modelagem de séries temporais e, em particular, neste trabalho, na previsão de curto prazo de gasolina automotiva. / [en] In this dissertation a short term model to forecast automotive gasoline demand in Brazil is proposed. From the methodology point of view, data is analyzed and a model using a bottom-up strategy is developed. In other words, a simple model is improved step by step until a proper model that sits well the reality is found. Departuring from a univariate model it ends up in a neural network formulation, passing through dynamic regression models. The models obtained in this scheme are compared according to some criterion, mainly forecast accuracy. We conclude, that the efficiency of putting together classical statistics models (such as Box & Jenkins and dynamic regression) and neural networks improve the forecasting results. This results is highly desirable in modeling time series and, particularly, to the short term forecast of automotive gasoline, object of this dissertation.