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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.
121

Comércio internacional, um modelo para segurança portuária de modernização da aduana brasileira. / International trade, a model for port security and Brazilian Customs modernization.

Russo Filho, Antonio 01 September 2006 (has links)
Este trabalho consta da apresentação de um modelo, denominado de Plano de Segurança Aduaneira Portuária (PSAP), a ser implementado pela Secretaria da Receita Federal, a partir de suas unidades locais, denominadas de ?Inspetorias da Receita Federal? ou de ?Alfândega de determinado Porto ou Aeroporto?. Foi desenvolvido especificamente para os portos alfandegados brasileiros e considera uma implantação gradual e acompanhada, a partir de um projeto piloto a ser testado no Porto de Santos. O PSAP consiste na automação de todos os processos e controles da atividade portuária, com utilização de alta tecnologia para a fiscalização da aduana, mediante inspeção não-intrusiva de contêineres, sua lacração e rastreamento na zona portuária. Centralizando os dados de diversos sistemas de controle das atividades portuárias em uma Central de Tratamento das Informações (CTI) e trabalhando esses registros mediante o cruzamento de todos os dados disponíveis. O Plano busca, com o resultado dessa análise integral, disparar uma ação fiscal específica, baseada na determinação do ?risco? potencial da carga, com probabilidade de elevado grau de sucesso da operação. Além das necessidades de equipamentos e software, o modelo define todas as rotinas operacionais para a utilização desses recursos de maneira eficaz e duradoura garantindo a viabilidade do modelo. A apresentação deste trabalho está subdividida em sete itens: apresentação geral da pesquisa; apreciação do conceito de segurança; informações sobre o estado da arte, por meio de conhecimentos sobre o modelo atualmente vigente na aduana brasileira; análise dos acordos internacionais sobre segurança assinados pelo Brasil; apresentação do Porto de Santos, por selecioná-lo como o de maior relevância e local para o plano piloto do modelo proposto; caracterização e descrição do modelo e conclusão, com argumentos favoráveis à implantação do PSAP. Finalmente, a justificativa da pertinência do modelo para a Secretaria da Receita Federal, é a certeza de que ele propiciará uma melhor fiscalização aduaneira, o que resultará em eficácia na prevenção e no combate aos crimes de contrabando, descaminho, pirataria e contrafação. / This work is the presentation of a model named as ?Plano de Segurança Aduaneira Portuaria? (Customs Port Security Plan) ? PSAP to be implemented by ?Secretaria da Receita Federal?, throughout its local units called ?Inspetorias da Receita Federal? or ?Alfândega? at a certain Seaport or Airport. It was developed specially for the Brazilian Custom Ports and it is considered a gradual implementation followed closely, starting with a pilot project to be tested at Port of Santos. The PSAP plan consists of the automation of the processes and controls of the port activities, utilizing advance technology for Customs examinations through non-intrusive container inspections of the containers within the port to include their seal and tracking and security in the port area. Centralizing all electronic data coming from different control systems of activities within port area in a ?Central de Tratamento das Informações? (Central Treatment of Information) ? CTI and working these information by utilizing all the data available. The Plan looks for the best action should be taken with the results of that entire analysis based on determines the potential cargo risk and which with a high probability successful operation. Besides the equipment and software needs, the model defines all operational routine to utilize these resources in an efficient and lasting way of using those riches providing the model viability. The presentation of this work is divided in seven items the research general presentation, shows security concepts,. It tells the condition of the art through the knowledge of the present model in Brazilian Customs, it analyzes the international agreements regarding security signed up by Brazil, introduction of Port of Santos selected like the most relevant and the place for the proposed plan pilot project, it describes the model after the characterization and concludes with argues that justify the implementation of the PSAP. Finishing, the argue that justifies the opportunity of the model to the ?Secretaria da Receita Federal? is the certainty that it will provide a better customs inspection so will result in effective way preventing and combating against crimes like smuggling fraud piracy and counterfeit.
122

Rede neural convolucional aplicada à identificação de equipamentos residenciais para sistemas de monitoramento não-intrusivo de carga / Convolutional neural network applied to the identification of residential equipment for non-intrusive load monitoring systems

PENHA, Deyvison de Paiva 03 April 2018 (has links)
Submitted by Kelren Mota (kelrenlima@ufpa.br) on 2018-06-25T18:48:12Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_RedeNeuralConvolucional.pdf: 2088560 bytes, checksum: 6328f6f59bc552055a366b1e4a32793d (MD5) / Approved for entry into archive by Kelren Mota (kelrenlima@ufpa.br) on 2018-06-25T18:48:32Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_RedeNeuralConvolucional.pdf: 2088560 bytes, checksum: 6328f6f59bc552055a366b1e4a32793d (MD5) / Made available in DSpace on 2018-06-25T18:48:32Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_RedeNeuralConvolucional.pdf: 2088560 bytes, checksum: 6328f6f59bc552055a366b1e4a32793d (MD5) Previous issue date: 2018-04-03 / Este trabalho apresenta a proposta de uma nova metodologia para identificação de equipamentos residenciais em sistemas de Monitoramento Não-Intrusivo de cargas. O sistema é baseado em uma Rede Neural Convolucional para classificação dos equipamentos, que utilizam, diretamente como entradas para o sistema, os dados do sinal transitório de potência de 7 equipamentos obtidos no momento em que estes são ligados em uma residência. A metodologia foi desenvolvida usando dados de um banco de dados público (REED) que apresenta dados coletados a uma baixa frequência (1 Hz). Os resultados obtidos na base de dados de testes apresentam acurácia superior a 90%, indicando que o sistema proposto é capaz de realizar a tarefa de identificação, além disso os resultados apresentados são considerados satisfatórios quando comparados com os resultados já apresentados na literatura para o problema em questão. / This research presents the proposal of a new methodology for the identification of residential equipment in non-intrusive load monitoring systems. The system is based on a Convolutional Neural Network to classify residential equipment, which uses directly as inputs to the system, the transient power signal data of 7 equipment obtained at the moment they are connected in a residence. The methodology was developed using data from a public database (REED) that presents data collected at a low frequency (1 Hz). The results obtained in the test database show an accuracy of more than 90%, indicating that the proposed system is capable of performing the task of identification. In addition, the results presented are considered satisfactory when compared with the results already presented in the literature for the problem in question.
123

Méthodes de réduction de modèles appliquées à des problèmes d'aéroacoustique résolus par équations intégrales / Reduced order methods applied to aeroacoustic problems solved by integral equations

Casenave, Fabien 05 December 2013 (has links)
Cette thèse s'articule autour de deux thématiques : les méthodes numériques pour la propagation d'ondes acoustiques sous écoulement et les méthodes de réduction de modèles. Dans la première thématique, nous développons une méthode de couplage d'éléments finis et d'éléments de frontière pour résoudre l'équation d'Helmholtz convectée, lorsque l'écoulement est uniforme à l'extérieur d'un domaine borné. En particulier, nous proposons une formulation bien posée à toutes les fréquences de la source. Dans la deuxième thématique, nous proposons une solution au problème classique d'accumulation d'arrondis machine qui survient en calculant l'estimateur d'erreur a posteriori dans la méthode des bases réduites. Par ailleurs, nous proposons une méthode non intrusive pour calculer une approximation sous forme séparée des systèmes linéaires résultant de l'approximation en dimension finie de problèmes aux limites dépendant d'un ou plusieurs paramètres / This thesis has two topics : numerical methods for acoustic wave propagation in a flow and reduced order models. In the first topic, we develop a coupled finite element and boundary element method to solve the convected Helmholtz equation, when the flow is uniform outside a bounded domain. In particular, we propose a formulation that is well-posed at all the frequencies of the source. In the second topic, we propose a solution to the classical problem of round-off error accumulation that occurs when computing the a posteriori error bound in the reduced basis method. Furthermore, we propose a non intrusive method for the approximation, in a separated representation form, of linear systems resulting from the finite-dimensional approximation of boundary-value problems depending on one or several parameters
124

Comércio internacional, um modelo para segurança portuária de modernização da aduana brasileira. / International trade, a model for port security and Brazilian Customs modernization.

Antonio Russo Filho 01 September 2006 (has links)
Este trabalho consta da apresentação de um modelo, denominado de Plano de Segurança Aduaneira Portuária (PSAP), a ser implementado pela Secretaria da Receita Federal, a partir de suas unidades locais, denominadas de ?Inspetorias da Receita Federal? ou de ?Alfândega de determinado Porto ou Aeroporto?. Foi desenvolvido especificamente para os portos alfandegados brasileiros e considera uma implantação gradual e acompanhada, a partir de um projeto piloto a ser testado no Porto de Santos. O PSAP consiste na automação de todos os processos e controles da atividade portuária, com utilização de alta tecnologia para a fiscalização da aduana, mediante inspeção não-intrusiva de contêineres, sua lacração e rastreamento na zona portuária. Centralizando os dados de diversos sistemas de controle das atividades portuárias em uma Central de Tratamento das Informações (CTI) e trabalhando esses registros mediante o cruzamento de todos os dados disponíveis. O Plano busca, com o resultado dessa análise integral, disparar uma ação fiscal específica, baseada na determinação do ?risco? potencial da carga, com probabilidade de elevado grau de sucesso da operação. Além das necessidades de equipamentos e software, o modelo define todas as rotinas operacionais para a utilização desses recursos de maneira eficaz e duradoura garantindo a viabilidade do modelo. A apresentação deste trabalho está subdividida em sete itens: apresentação geral da pesquisa; apreciação do conceito de segurança; informações sobre o estado da arte, por meio de conhecimentos sobre o modelo atualmente vigente na aduana brasileira; análise dos acordos internacionais sobre segurança assinados pelo Brasil; apresentação do Porto de Santos, por selecioná-lo como o de maior relevância e local para o plano piloto do modelo proposto; caracterização e descrição do modelo e conclusão, com argumentos favoráveis à implantação do PSAP. Finalmente, a justificativa da pertinência do modelo para a Secretaria da Receita Federal, é a certeza de que ele propiciará uma melhor fiscalização aduaneira, o que resultará em eficácia na prevenção e no combate aos crimes de contrabando, descaminho, pirataria e contrafação. / This work is the presentation of a model named as ?Plano de Segurança Aduaneira Portuaria? (Customs Port Security Plan) ? PSAP to be implemented by ?Secretaria da Receita Federal?, throughout its local units called ?Inspetorias da Receita Federal? or ?Alfândega? at a certain Seaport or Airport. It was developed specially for the Brazilian Custom Ports and it is considered a gradual implementation followed closely, starting with a pilot project to be tested at Port of Santos. The PSAP plan consists of the automation of the processes and controls of the port activities, utilizing advance technology for Customs examinations through non-intrusive container inspections of the containers within the port to include their seal and tracking and security in the port area. Centralizing all electronic data coming from different control systems of activities within port area in a ?Central de Tratamento das Informações? (Central Treatment of Information) ? CTI and working these information by utilizing all the data available. The Plan looks for the best action should be taken with the results of that entire analysis based on determines the potential cargo risk and which with a high probability successful operation. Besides the equipment and software needs, the model defines all operational routine to utilize these resources in an efficient and lasting way of using those riches providing the model viability. The presentation of this work is divided in seven items the research general presentation, shows security concepts,. It tells the condition of the art through the knowledge of the present model in Brazilian Customs, it analyzes the international agreements regarding security signed up by Brazil, introduction of Port of Santos selected like the most relevant and the place for the proposed plan pilot project, it describes the model after the characterization and concludes with argues that justify the implementation of the PSAP. Finishing, the argue that justifies the opportunity of the model to the ?Secretaria da Receita Federal? is the certainty that it will provide a better customs inspection so will result in effective way preventing and combating against crimes like smuggling fraud piracy and counterfeit.
125

Mesure et modlisation dynamique de la couche de gele dans un racteur mtallurgique

Bertrand, Clment January 2014 (has links)
Rsum : La mesure des profils transitoires et de la vitesse de solidification sont deux donnes importantes pour le contrle de procds industriels impliquant un changement de phase. Dans le cas de llectrolyse de laluminium, ce processus de solidification assure la protection du systme et influe sur la performance nergtique du procd de fabrication. Malheureusement, ces donnes se rvlent, dans la plupart des cas, difficilement accessibles. Ce travail de thse porte sur le dveloppement de nouveaux outils permettant ltude et la caractrisation de la solidification de matriaux changement de phase et haute temprature. Lobjectif est de dvelopper un systme de mesure du front de solidification de matriaux changement de phase non destructif et ne perturbant pas le milieu de mesure, tout en assurant une prcision et une rponse suffisamment rapide pour exploiter de nouvelles stratgies de contrle dans les cuves dlectrolyse. Ce travail couple une tude exprimentale fondamentale de la solidification de la cryolithe avec une modlisation numrique de phnomne de changement de phase solide-liquide dans des conditions proches du fonctionnement de cuves dlectrolyse. // Abstract : Measurement of transient solidification fronts and of solidification rate are two important data for controlling industrial processes involving a solid-liquid phase change. In the case of aluminium electrolysis, this solidification process protects the system and affects the energy performance of the manufacturing process. Unfortunately, these data are not easy to obtain in most cases. This thesis focuses on the development of new tools for the study and on the solidification characterization of phase change materials at high temperature. The goal is to develop a nondestructive solidification front measurement system for phase change materials without disturbing the measurement medium, while ensuring accuracy and a fast enough response time to exploit new control strategies in electrolysis cells. This work couples a fundamental experimental study of the cryolite solidification with numerical modeling of solid-liquid phase change phenomenon under conditions close to those during normal operation of electrolytic cells.
126

Investigation of circuit breaker switching transients for shunt reactors and shunt capacitors

Ramli, Mohd Shamir January 2008 (has links)
Switching of shunt reactors and capacitor banks is known to cause a very high rate of rise of transient recovery voltage across the circuit breaker contacts. With improvements in circuit breaker technology, modern SF6 puffer circuits have been designed with less interrupter per pole than previous generations of SF6 circuit breakers. This has caused modern circuit breakers to operate with higher voltage stress in the dielectric recovery region after current interruption. Catastrophic failures of modern SF6 circuit breakers have been reported during shunt reactor and capacitor bank de-energisation. In those cases, evidence of cumulative re-strikes has been found to be the main cause of interrupter failure. Monitoring of voltage waveforms during switching would provide information about the magnitude and frequency of small re-ignitions and re-strikes. However, measuring waveforms at a moderately high frequency require plant outages to connect equipment. In recent years, there have been increasing interests in using RF measurements in condition monitoring of switchgear. The RF measurement technique used for measuring circuit breaker inter-pole switching time during capacitor bank closing is of particular interest. In this thesis, research has been carried out to investigate switching transients produced during circuit breaker switching capacitor banks and shunt reactors using a non-intrusive measurement technique. The proposed technique measures the high frequency and low frequency voltage waveforms during switching operations without the need of an outage. The principles of this measurement technique are discussed and field measurements were carried out at shunt rector and capacitor bank installation in two 275 kV air insulated substations. Results of the measurements are presented and discussed in this thesis. The proposed technique shows that it is relatively easy to monitor circuit breaker switching transients and useful information on switching instances can be extracted from the measured waveforms. Further research works are discussed to realise the full potential of the measuring technique.
127

Preservando a privacidade de Smart Grids através de adição de ruído. / Preserving the privacy of Smart Grids through addition of noise.

BARBOSA, Pedro Yóssis Silva. 06 August 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-08-06T18:59:56Z No. of bitstreams: 1 PEDRO YÓSSIS SILVA BARBOSA - DISSERTAÇÃO PPGCC 2014..pdf: 17089632 bytes, checksum: 4623777c293a51dbb1b392f37d2dd75e (MD5) / Made available in DSpace on 2018-08-06T18:59:56Z (GMT). No. of bitstreams: 1 PEDRO YÓSSIS SILVA BARBOSA - DISSERTAÇÃO PPGCC 2014..pdf: 17089632 bytes, checksum: 4623777c293a51dbb1b392f37d2dd75e (MD5) Previous issue date: 2014-02-27 / Capes / Companhias de energia começaram a substituir os medidores de energia tradicionais pelos Smart Meters, que podem transmitir valores de consumo para as companhias em curtos intervalos de tempo. Com uma insfraestrutura de Smart Meters, existem muitas motivações para as concessionárias de energia coletarem dados de consumo em alta resolução. Entretanto, isto implica em informações bastante detalhadas sobre os consumidores sendo monitoradas. Consequentemente, um problema sério precisa ser resolvido: como preservar a privacidade dos consumidores sem afetar a prestação de certos serviços pelas concessionárias? Claramente, este é um tradeoff entre privacidade e utilidade. Existem diversas abordagens para preservar a privacidade, porém muitas delas afetam a utilidade dos dados ou possuem um alto custo computacional. Neste trabalho, nós propomos e avaliamos uma abordagem computacionalmente barata que preserva a privacidade e utilidade dos dados através de adição de ruído. Para validar a privacidade, nós avaliamos possíveis ataques (tal como Monitoramento Não-Intrusivo de Carga de Eletrodomésticos - NIALM, do inglês Non-Intrusive Appliance Load Monitoring) utilizando dados reais de consumidores. Para validar a utilidade, nós avaliamos a influência da abordagem em vários benefícios que podem ser providos com o uso de Smart Meters. / Power providers have started replacing traditional electricity meters for Smart Meters, which can transmit power consumption levels to the provider within short intervals. With a Smart Metering infrastructure, there are many motivations for power providers to collect highresolution data of electricity usage from consumers. However, this implies in very detailed information about the consumers being monitored. Consequently, a serious issue needs to be addressed: how to preserve the privacy of consumers but making the provision of certain services still possible? Clearly, this is a tradeoff between privacy and utility. There are several approaches for privacy preserving, but many of them affect the data usefulness or are computationally expensive. In this work, we propose and evaluate a lightweight approach for privacy and utility based on the addition of noise. To validate the privacy, we evaluate possible attacks (such as a NIALM - Non-Intrusive Appliance Load Monitoring) using real consumers' data. To validate the utility, we analyze the influence of the approach in various benefits that can be provided through the use of Smart Meters.
128

Estudo Paleomagnético de Unidades Paleoproterozóicas do Cráton Amazônico / Paleomagnetic Study of Paleoproterozoic Units from Amazonian Craton

Franklin Bispo dos Santos 03 May 2012 (has links)
Na América do Sul, o Cráton Amazônico representa um componente essencial nas reconstruções de supercontinentes, entretanto, há uma grande escassez de dados paleomagnéticos de qualidade para esta unidade geotectônica, principalmente, para o Proterozóico. Com o intuito de esclarecer a participação do Cráton Amazônico na evolução do ciclo continental, este trabalho apresenta um estudo paleomagnético realizado em quatro unidades geológicas Paleo- a Mesoproterozóicas pertencentes ao Cráton Amazônico. As unidades escolhidas para este estudo foram às rochas vulcânicas do Grupo Surumu (1980-1960 Ma, U-Pb), as soleiras máficas Avanavero (ca. 1780 Ma, U-Pb) ambas situadas no norte do Estado de Roraima (Escudo das Guianas), os enxames de diques Nova Guarita e a intrusiva máfica Guadalupe ambas localizadas no norte do Estado do Mato Grosso (Escudo Brasil-Central). Determinações 40Ar/39Ar realizadas em biotitas de quatro diques de Nova Guarita mostraram resultados coerentes, fornecendo uma idade média de 1418,5 ± 3,5 Ma para a época de intrusão dos diques. Idades U-Pb obtidas em rochas da intrusiva máfica Guadalupe indicam uma idade mínima de 1530 Ma para estas amostras. As análises paleomagnéticas realizadas em mais de 1100 espécimes de rocha através dos tratamentos térmicos e por campos magnéticos alternados revelaram direções características coerentes para as quatro unidades de rochas estudadas: (1) as rochas do Grupo Surumu apresentaram direções noroeste com inclinações positivas. Foi calculada uma direção média Dm = 298,6°, Im = 39,4° (N = 20, alfa95 = 10,1°, K = 11,4), a qual foi interpretada como sendo de origem primária; (2) as rochas máficas Avanavero apresentaram direções sudeste com inclinações positivas/negativas baixas, sendo determinada uma direção média Dm = 135,6°, Im = -2,1° (N = 10, alfa95 = 15,9°, K = 10,2°). Um teste de contato cozido realizado para um dos sítios amostrados atesta o caráter primário da magnetização remanente isolada, a qual foi adquirida pelas rochas há ca.1780 Ma atrás; (3) os diques máficos Nova Guarita apresentaram polaridades reversas e normais, tendo sido isoladas direções sul/sudoeste com inclinações positivas e nordeste com inclinações negativas. Um teste de contato cozido positivo foi obtido para um dique que intrude o Granito Matupá, o qual confirma que a magnetização remanente (Dm = 220,5°, Im = 45,9°, N = 19, alfa95 = 6,5°, K = 27,7) isolada para estas rochas corresponde a uma magnetização termorremanente adquirida durante a formação da rocha há ca. 1419 Ma atrás; (4) rochas pertencentes a Intrusiva Máfica Guadalupe também apresentaram polaridades reversas e normais. Direções noroeste/nordeste com inclinações positivas ou sul/sudeste com inclinações negativas foram isoladas para estas rochas, para as quais foi calculada a direção média Dm = 356,6°, Im = 59,4°, (N = 10, alfa95 = 10,2°, K = 23,2). A idade desta componente, entretanto, ainda não está bem estabelecida, podendo representar uma remagnetização adquirida durante o evento Brasiliano, já que ela é similar às magnetizações adquiridas há 520 Ma, presentes em formações geológicas do Cráton Amazônico e do Cráton do São Francisco. A caracterização da mineralogia magnética de todas as amostras investigadas foi obtida através de curvas termomagnéticas, curvas de histerese e curvas de magnetização remanente isotérmica. Quatro pólos paleomagnéticos para o Cráton Amazônico foram determinados para estas componentes, os quais estão localizados em 234,8° E, 27,4°N (A95=9,8°) (pólo GS, Grupo Surumu), 27,5°E, -45,8°N (A95=11,5°) (pólo AV, Avanavero), 245,9°E, -47,9°N (A95=7,0°) (pólo NG, Nova Guarita) e 306,2°E, 38,9°N (A95=13,7°) (pólo GUA, Guadalupe). Os resultados paleomagnéticos obtidos para as rochas Surumu (pólo GS) contribuíram para um melhor ajuste da curva de deriva polar aparente (CDPA) para o Escudo das Guianas durante o Paleoproterozóico (2070-1960 Ma). A comparação desta CDPA com a construída para o Cráton Oeste-África para o mesmo período de tempo sugere que estes blocos cratônicos estavam unidos há 1970-2000 Ma atrás, em uma paleogeografia em que as zonas de cisalhamento Guri, no Escudo das Guianas, e Sassandra, no Cráton Oeste-África estavam alinhadas como sugerido em modelos anteriores. O pólo Avanavero de 1780 Ma é consistente com a paleogeografia do supercontinente Columbia em que o proto-Cráton Amazônico e a Báltica estavam unidos como no modelo SAMBA (South America-Baltica) proposto anteriormente com base em evidências geológicas. No cenário proposto aqui para o Supercontinente Columbia há 1780 Ma atrás, o Cráton Oeste-África estava unido ao proto-Cráton Amazônico na mesma configuração sugerida pelos dados paleomagnéticos de 1790-2000 Ma. O atual lado leste da Laurentia estava unido ao norte (atual) da Báltica. A Sibéria estava unida com a atual costa Ártica da Laurentia e a proto-Austrália, com a atual costa oeste da Laurentia, em posição similar ao modelo SWEAT. Embora os dados paleomagnéticos disponíveis para o Cráton Norte da China e Índia indiquem paleolatitudes equatorias para estes dois blocos, nesta época, suas posições no supercontinente Columbia são ainda incertas. No modelo do Columbia apresentado neste trabalho, o Norte da China foi colocado ao lado da Sibéria e a Índia, ao lado da proto-Austrália, em decorrência de evidências geológicas. Outros blocos cratônicos, tais como, Congo-São Francisco, Kalahari e Rio de La Plata não foram incluídos, pela ausência de pólos paleomagnéticos desta idade. Os dados paleomagnéticos atualmente existentes para a Báltica e a Laurentia mostram que estes dois blocos continentais permaneceram unidos desde 1830 Ma até, pelo menos, 1270 Ma atrás. Já o pólo paleomagnético obtido para os diques Nova Guarita de 1419 Ma e o pólo de mesma idade, recentemente obtido para a Intrusiva Indiavaí, quando comparados com pólos de mesma idade da Báltica e da Laurentia, sugerem que o proto-Craton Amazônico já havia iniciado sua ruptura no Supercontinente Columbia nessa época. De modo alternativo, porém, essa diferença na posição dos pólos do proto-Cráton Amazônico e da Báltica/Laurentia, pode ser explicada por movimentos transcorrentes dextrais que teriam ocorrido entre o Escudo das Guianas e a parte sul do Cráton Amazônico em tempos posteriores a 1420 Ma. Neste caso, esta grande massa continental do Supercontinente Columbia, composta pelo proto-Cráton Amazônico, Báltica e Laurentia, pode ter permanecida unida por, pelo menos, 400 Ma. / The Amazonian Craton is an important component in Paleoproterozoic reconstructions, however, paleomagnetic data for this craton are yet scarce. Aiming to decipher the involvement of the Amazonian Craton in the Contiental cycle evolution, paleomagnetic studies were carried out in four Paleo- to Mesoproterozoic geological units. The chosen units are the volcanic rocks from the Surumu Group (1,980-1,960 Ma, U-Pb), the Avanavero mafic sills (ca. 1,780 Ma, U-Pb), both from the northern Roraima State (Guyana Shield), and the Nova Guarita dyke swarm and Guadalupe mafic intrusive, both from the northern Mato Grosso State (Central- Brazil Shield). 40Ar/39Ar determinations on biotites from samples belonging to four Nova Guarita dykes yielded well-defined plateau ages whose mean 1,418.5 ± 3.5 Ma is interpreted as the age of dyke intrusion. U-Pb (SHRIMP) determinations on rocks from the Guadalupe mafic Intrusive indicate a minimum age of 1,530 Ma for this unit. Paleomagnetic analysis performed on more than 1,100 specimens by thermal and alternating magnetic field (AF) treatments revealed stable characteristic remanent magnetizions (ChRM) for all geological units: (1) northwestern directions with positive inclinations were isolated for samples from the Surumu Group (mean: Dm = 298.6°, Im = 39.4°, N = 20, alpha95 = 10.1°, K = 11.4), which were interpreted to be primary. (2) Southeastern directions with low downward/upward inclinations were isolated for the Avanavero rocks, for which a mean direction was calculated: Dm=135.6°, Im = -2.1° (N=10, alpha95 = 15.9°, K = 10.2°). A positive baked contact test attests for the primary origin of this ChRM direction, which was probably acquired at about 1,780 Ma ago; (3) both south/southwestern directions with downward inclinations or northeastern directions with upward inclinations were isolated for the Nova Guarita dykes. A positive baked contact test attests for the primary nature of the ChRM directions (Dm = 220.5°, Im = 45.9°, N=19, alpha95=6.5°, K = 27.7) which most probably correspond to a termo-remanent magnetization (TRM) acquired at ca. 1,419 Ma ago; 10 (4) both northwest/northeastern directions with downward inclinations or outhsoutheastern directions with upward inclinations were isolated for rocks from the Guadalupe intrusive, whose mean direction is: Dm=356.6°, Im=59.4°, (N =10, alpha95=10.2°, K = 23.2). The age of this component is yet uncertain. U-Pb geochronology suggests an age of (or older than) 1,530 Ma for these rocks, however, a remagnetization effect at Cambrian times (520 Ma) cannot be rolled out as these directions are very similar to those found for younger geological units in the Amazonian Craton and Sao Francisco Craton. Four new paleomagnetic poles for the Amazonian Craton were obtained from these magnetic components, which are located at: 234.8°E, 27.4°N (A95=9.8°) (GS pole, Surumu Group), 27.5°E, 45.8°S (A95=11.5°) (AV pole, Avanavero), 245.9°E, 47.9°S (A95=7.0°) (NG pole, Nova Guarita) and 306.2°E, 38.9°N (A95 = 13.7°) (GUA pole, Guadalupe). The 1,960 Ma Surumu pole contributes to better define the APW path traced for the Guyana Shield in the time interval between 2,070 Ma and 1,960 Ma. Comparison of this APW path with that traced for West-Africa Craton for the same time interval suggests that these two cratonic blocks were linked together, in a paleogeography where the Guri (Guyana Shield) and Sassandra (West-Africa Craton) shear zones are aligned, as suggested by previous models. The Avanavero pole is consistent with the proto-Amazonian Craton and Baltica link as in the SAMBA (South America-Baltica) model at ca. 1,780 Ma ago, as previously proposed based on geological evidence. In the scenario proposed here for the Columbia Supercontinent at 1,780 Ma ago, the West-Africa Craton was linked to the proto-Amazonian Craton in the same configuration as suggested by Paleoproterozoic (1,960-2,000 Ma) paleomagnetic data (see above). Actual eastern Laurentia was linked to northern Baltica. Siberia was located at the actual Arctic Coast of Laurentia, and proto-Australia at the western coast of Laurentia, in a position similar to that of SWEAT model. Although available 1,780 Ma paleomagnetic data from North China and India indicate low paleolatitudes for these two blocks, their positions in the supercontinent Columbia are yet uncertain. In our model, North China is located beside Siberia, and India beside proto-Australia, based on geological evidences. Other cratonic blocks, such as Congo-Sao Francisco, Kalahari and Rio de la Plata were not included as no 1,780 Ma paleomagnetic poles are presently available for them. The paleomagnetic poles presently available for Baltica and Laurentia, show that these two blocks remained as a single continental mass since 1,830 Ma up to at least 1,270 Ma. However, the 1,419 Ma Nova Guarita pole and the recently published 1,416 Ma Indiavai pole from the Amazonian Craton, when compared with poles of similar age from Baltica and Laurentia suggest that the proto-Amazonian Craton had already broke-up from the Columbia Supercontinent at that time. Alternatively, the difference in the position of the 1,420 Ma poles from the proto-Amazonian Craton and those from Baltica/Laurentia, may be explained by dextral transcurrent movements between the Guyana Shield and the southern part of the Amazonian Craton at times later than 1,420 Ma. If so, this great continental mass, formed by proto-Amazonian Craton, Baltica and Laurentia may have remained as a single continental block for at least 400 Ma.
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Improving performance of non-intrusive load monitoring with low-cost sensor networks / Amélioration des performances de supervision de charges non intrusive à l'aide de capteurs sans fil à faible coût

Le, Xuan-Chien 12 April 2017 (has links)
Dans les maisons et bâtiments intelligents, il devient nécessaire de limiter l'intervention humaine sur le système énergétique, afin de fluctuer automatiquement l'énergie consommée par les appareils consommateurs. Pour cela, un système de mesure de la consommation électrique d'équipements est aussi nécessaire et peut être déployé de deux façons : intrusive ou non-intrusive. La première solution consiste à relever la consommation de chaque appareil, ce qui est inenvisageable à une grande échelle pour des raisons pratiques liées à l'entretien et aux coûts. Donc, la solution non-intrusive (NILM pour Non-Intrusive Load Monitoring), qui est capable d'identifier les différents appareils en se basant sur les signatures extraites d'une consommation globale, est plus prometteuse. Le problème le plus difficile des algorithmes NILM est comment discriminer les appareils qui ont la même caractéristique énergétique. Pour surmonter ce problème, dans cette thèse, nous proposons d'utiliser une information externe pour améliorer la performance des algorithmes existants. Les premières informations additionnelles proposées considèrent l'état précédent de chaque appareil comme la probabilité de transition d'état ou la distance de Hamming entre l'état courant et l'état précédent. Ces informations sont utilisées pour sélectionner l'ensemble le plus approprié des dispositifs actifs parmi toutes les combinaisons possibles. Nous résolvons ce problème de minimisation en norme l1 par un algorithme d'exploration exhaustive. Nous proposons également d'utiliser une autre information externe qui est la probabilité de fonctionnement de chaque appareil fournie par un réseau de capteurs sans fil (WSN pour Wireless Sensor Network) déployé dans le bâtiment. Ce système baptisé SmartSense, est différent de la solution intrusive car seul un sous-ensemble de tous les dispositifs est surveillé par les capteurs, ce qui rend le système moins intrusif. Trois approches sont appliquées dans le système SmartSense. La première approche applique une détection de changements de niveau sur le signal global de puissance consommé et les compare avec ceux existants pour identifier les dispositifs correspondants. La deuxième approche vise à résoudre le problème de minimisation en norme l1 avec les algorithmes heuristiques de composition Paréto-algébrique et de programmation dynamique. Les résultats de simulation montrent que la performance des algorithmes proposés augmente significativement avec la probabilité d'opération des dispositifs surveillés par le WSN. Comme il n'y a qu'un sous-ensemble de tous les appareils qui sont surveillés par les capteurs, ceux qui sont sélectionnés doivent satisfaire quelques critères tels qu'un taux d'utilisation élevé ou des confusions dans les signatures sélectionnées avec celles des autres. / In smart homes, human intervention in the energy system needs to be eliminated as much as possible and an energy management system is required to automatically fluctuate the power consumption of the electrical devices. To design such system, a load monitoring system is necessary to be deployed in two ways: intrusive or non-intrusive. The intrusive approach requires a high deployment cost and too much technical intervention in the power supply. Therefore, the Non-Intrusive Load Monitoring (NILM) approach, in which the operation of a device can be detected based on the features extracted from the aggregate power consumption, is more promising. The difficulty of any NILM algorithm is the ambiguity among the devices with the same power characteristics. To overcome this challenge, in this thesis, we propose to use an external information to improve the performance of the existing NILM algorithms. The first proposed additional features relate to the previous state of each device such as state transition probability or the Hamming distance between the current state and the previous state. They are used to select the most suitable set of operating devices among all possible combinations when solving the l1-norm minimization problem of NILM by a brute force algorithm. Besides, we also propose to use another external feature that is the operating probability of each device provided by an additional Wireless Sensor Network (WSN). Different from the intrusive load monitoring, in this so-called SmartSense system, only a subset of all devices is monitored by the sensors, which makes the system quite less intrusive. Two approaches are applied in the SmartSense system. The first approach applies an edge detector to detect the step-changes on the power signal and then compare with the existing library to identify the corresponding devices. Meanwhile, the second approach tries to solve the l1-norm minimization problem in NILM with a compositional Pareto-algebraic heuristic and dynamic programming algorithms. The simulation results show that the performance of the proposed algorithms is significantly improved with the operating probability of the monitored devices provided by the WSN. Because only part of the devices are monitored, the selected ones must satisfy some criteria including high using rate and more confusions on the selected patterns with the others.
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Kontaktlös flödesmätning med trådlös dataöverföring : Undersökning av kostnadseffektiva system

Svensson, Sonny January 2017 (has links)
Målet med undersökningen har varit att undersöka möjligheten att ta fram en kostnadseffektiv lösning för att mäta flöden i slutna rörsystem. Anledningen till att kontaktlösa metoder valts för arbetet är dess egen-skaper att kunna installeras utan att göra ingrepp i ledningarna eller på något sätt påverka det flödande mediet i dessa. Utrustning skall inhand-las och testas i fält. I underökningen ingår det även att ta fram en lämplig metod för att trådlöst överföra insamlat mätdata till valfri IT-miljö och där kunna presentera mätdata på ett översiktligt sätt i ett övervaknings-system samt använda mätdatat till olika statistiska beräkningar. Det hu-vudsakliga applikationsområdet som undersöks är läckageindikering i dricksvattenledningsnät. Anledningen till detta är att många kommuner inte har råd att investera i dyr mätutrustning för övervakning och för dem kan det vara intressant med ett billigt system som är relativt enkelt att installera och implementera i deras befintliga övervakningssystem. Re-sultat av en enkätundersökning som gjorts i samband med undersök-ningen har visat att intresset är stort hos kommunerna, men den visar även att övervakning av vattenledningsnäten med vissa traditionella me-toder kommer att bli svårare i framtiden i och med den stigande andelen plaströr i ledningsnäten. Fälttester av inköpt mätutrustning visar att den skulle kunna implementeras och fungera som flödesövervakning i led-ningsnät. Även fast dess mätnoggrannhet var under det förväntade så vi-sade utrustningen på god linjäritet. / The aim of the survey has been to investigate the possibilities of using a cost-effective solution for measuring flows in closed pipes. Non-intrusive measuring methods are chosen because it’s able to install them without interfering the flow in- or alter- the pipe in any way. Equipment will be purchased and field tested during the time of the survey. The survey also includes investigating suitable methods for wirelessly transmitting col-lected data to an IT-environment, and using measurement data for sur-veillance purposes and various statistical calculations. The main applica-tion area investigated is leakage indication in drinking water pipeline net-works, the reason being that many municipalities can’t afford to invest in expensive measuring equipment and they may be interested in an inex-pensive system that is relatively easy to install and implement in their existing monitoring system. The results of a poll conducted in connection with the survey have shown that there is considerable interest among the municipalities, but it also shows that monitoring of the water supply net-works with traditional methods may become more difficult in the future, the main reason for this seems to be the increasing amount of plastic pipe-lines in the pipeline networks. Field tests of the purchased equipment show that it may be suitable to implement as flow measuring device with the purpose of leakage monitoring, even though its measurement accu-racy was below expected it still shows good linearity.

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