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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.
11

Off the rails: the cost performance of infrastructure rail projects

Love, P.E.D., Zhou, J., Edwards, D.J., Irani, Zahir, Sing, C-P. 2017 March 1914 (has links)
Yes / Governments in Australia place great emphasis on the development and expansion of their rail networks to improve productivity and service the increasing needs and demands from businesses and commuters. A case study approach is used to analyze the cost performance of 16 rail projects constructed by a contractor between 2011 and 2014, which ranged from AU$3.4 to AU$353 million. Findings indicate that scope changes during construction were the key contributors that lead to the amendment of each project’s original contractual value. As a result, there is a need for public and private sector asset owners to establish a cost contingency using a probabilistic rather than a deterministic approach to accommodate the potential for scope changes during construction. To improve cost certainty during the construction of rail projects, it is suggested that use of collaborative forms of procurement juxtaposed with the use of Building Information Modelling and Systems Information Modelling are implemented. The utilization of such technological and process innovations can provide public and private sector asset owners charged with delivering and maintaining their rail networks with confidence projects can be delivered within budget and are resilient to unexpected events and adaptable to changing needs, uses or capacities. / The authors would like to acknowledge the financial support provided by the Australian Research Council (DP160102882).
12

Imagerie à éclairements structurés inconnus / Blind-structured illumination microscopy for super-resolution imaging

Labouesse, Simon 06 November 2017 (has links)
La microscopie à éclairements structurés (SIM) permet théoriquement de doubler la résolution d’un microscope optique standard. Pour atteindre cette limite théorique, le SIM requière un contrôle très précis des illuminations, ce qui le rend coûteux et difficile à calibrer. Cette thèse cherche à simplifier drastiquement le principe du SIM en proposant une approche « aveugle » qui reconstruit une image de l’échantillon à partir d’éclairements aléatoires, i.e., très facile à générer. Cette stratégie permet en théorie l’imagerie super-résolue tout en réduisant fortement le coût de l’instrument. Nous avons étudié du point de vu théorique et algorithmique les performances et les limitations d’un estimateur joint de l’objet et des illuminations (estimateur Blind-SIM joint). Notamment, une reformulation mathématique du problème d’estimation jointe a été proposée qui permet d’analyser l'origine de la super-résolution mais également de proposer des nouvelles stratégies de mises en œuvre très rapides. Une étude empirique a mis en lumière l’impact de la parcimonie et du contenue fréquentielles des illuminations sur le niveau de super-résolution obtenu. L’estimateur joint étant asymptotiquement inconsistant, nous nous sommes également intéressé à définir un « critère de contraste » pour ce problème permettant d’estimer uniquement l’objet d’intérêt. Une étude mathématique de la capacité de super-résolution de ce type d'estimateur a été conduite. Enfin, on a observé un effet de super-résolution en condition réelles sur de nombreux objets, 2 ou 3D, fixe ou mobile, biologique ou non tel que des billes, des podosomes, de l’actine. / Structured illumination microscopy (SIM) allow theoretically to double the super-resolution of a standard optical microscope. However, to reach this theoretical limit, SIM require a precise knowledge of the illuminations, making it costly and difficult to calibrate. The aim of this thesis is to simplify the use of SIM by using a blind approach who allow the use of random illuminations to reconstruct a super-resolved image of the object. This strategy theoretically allow the super-resolution, while maintaining a low cost instrumentation. During those three years of thesis, we have studied theoretically and algorithmically the performances and the limitations of a joint estimator of the objet and the illuminations (joint Blind-SIM estimator). A mathematically equivalent reformulation of the joint problem was proposed allowing us to study the super-resolution origin and to propose a fast and parallelizable new approach. An empirical study has highlighted the impact of parsimony and of the frequency content of the illuminations on the reached super-resolution level. Because the joint estimator is asymptotically not consistent, we also studied a contrast criterion for our problem (typically a marginal likelihood), here only the object of interest is estimated. We have mathematically studied the super-resolution capacity of this kind of estimators. Finally, real data using random illuminations where acquired and we have observed a super-resolution effect using our algorithms on multiples real objects of different kind, 2 or 3D, fix or mobile, biological or not, like beads, podosomes, actines.
13

Análises multiresíduos de agrotóxicos em tomate (Lycopersicon esculentum Mill) utilizando CG-EM e monitoramento / Multiresidue analysis of pesticides in tomato (Lycopersicon esculentum Mill) using GC-MS and monitoring

Andrade, Graziela Cristina Rossi de Moura 23 July 2009 (has links)
A preocupação com os danos provocados à saúde do trabalhador rural e ao meio ambiente devido ao uso indiscriminado de agrotóxicos tem aumentado nos últimos anos. O uso generalizado e intensivo destas substâncias tem gerado diversos problemas relacionados à saúde pública e ao desequilíbrio ambiental, incluindo: intoxicações de agricultores, contaminação de alimentos, água e solos. O tomate é hoje, uma hortaliça bastante conhecida e de elevado consumo no mundo. Sua cultura é bastante afetada por quebras de rendimento e depreciação da qualidade de matéria- prima, em razão da ocorrência de doenças, pragas e estresses abióticos. Apesar da preocupação com o monitoramento dos resíduos de agrotóxicos nos alimentos, poucas metodologias analíticas podem alcançar resultados de alta qualidade simultaneamente para uma gama extensiva de agrotóxicos. No presente estudo, foi desenvolvida e validada a metodologia de análise de multirresíduos QuEChERS (quick, easy, cheap, effective, rugged, and safe) para quantificação de resíduos de agrotóxicos em tomate. Este método provê resultados de forma rápida, fácil, com custo acessível e com alta qualidade. Foram analisados agrotóxicos utilizados principalmente no controle de insetos, sendo: buprofezina, carbofurano, \'alfa\'-endossulfam, \'beta\'-endossulfam, sulfato de endossulfam e monocrotofós. Para isso, realizou-se a fortificação do tomate, previamente homogeneizado, com soluções contendo os agrotóxicos em 3 níveis de fortificação (0,0625; 0,25 e 1,00 mg/Kg). A purificação dos extratos foi realizada através de clean-up dispersivo, e em seguida os extratos foram analisados por CG-EM modo SIM. Neste estudo avaliaram-se os seguintes parâmetros de validação do método: linearidade da curva analítica, sensibilidade, limite de detecção (LD), limite de quantificação (LQ), o efeito matriz, bem como a precisão e a exatidão (em termos de percentual de recuperação). A faixa linear de concentração das curvas analíticas situou-se entre 0,25 a 4,0 ng.\'mü\'L-1 com valores de r2 maiores que 0,99 (na matriz). A técnica CG-EM modo SIM promoveu a quantificação (critérios de recuperação entre 70 e 120% e valores de CV% menores que 20%) de todos os agrotóxicos estudados. Portanto, conclui-se que o método mostrou-se adequado às análises multirresíduos dos agrotóxicos em tomate, apresentando sensibilidade e seletividade adequadas, e todos os parâmetros de validação encontram-se de acordo com os limites sugeridos para validação de métodos cromatográficos. Foram coletadas amostras (n=33) em varejões na cidade de Piracicaba e os níveis residuais de agrotóxicos apresentaram-se abaixo dos limites de detecção para os produtos analisados. Os produtos acefato, deltametrina, difenoconazole e fenpropatrina foram avaliados no sistema CG-EM e não apresentaram sensibilidade e seletividade nas condições cromatográficas aplicadas. A implementação de novos métodos cromatográficos para análise de resíduos de agrotóxicos em alimentos devem ser fomentados para contribuir com o monitoramento eficiente, visando avaliar a qualidade e segurança dos alimentos consumidos pela população, caracterizar as fontes de contaminação e proporcionar uma avaliação quanto ao uso inadequado e não autorizado dos agrotóxicos / The concernment about the damage caused to the health of rural workers and the environment due to indiscriminate use of pesticides has increased in recent years. The commonly and intensive use of these substances has created several problems related to public health and environmental disequilibrium, including poisoning of farmers, contamination of food, water and soil. Nowadays, the tomato is a well known vegetables and high consumption in the world. Its culture is highly affected by loss of yield and depreciation of the quality of raw material, due to the occurrence of diseases, pests and abiotic stresses. Considering the concernment about the monitoring of pesticide residues in food, few analytical methods can achieve high quality results for both a wide range of pesticides. In this study, was developed and validated the methodology of multiresidue analysis QuEChERS (quick, easy, cheap, effective, rugged, and safe) for quantification of residues of pesticides in tomatoes. This method provides results quick, easy, inexpensive and high quality. Were analyzed mainly pesticides used to control insects, are: buprofezina, carbofuran, \'alfa\'-endossulfam, \'beta\'- endossulfam, sulphate endossulfam and monocrotophos. Then, performed a spiking of tomatoes homogenized previously, with solutions containing pesticides, in 3 of fortification levels (0.0625, 0.25 and 1.00 mg/kg). The purification of the extracts was performed by dispersive clean-up, and then the extracts were analyzed by GC-MS using SIM mode. This study evaluated the following parameters for validation of the method: linearity, sensitivity, limit of detection (LOD), limit of quantification (LOQ), matrix effect, precision and accuracy (in terms of percentage of recovery). The linear range of concentration of the analytical curves was between 0.25 to 4.0 ng.\'mü\'L-1 with r2 values of greater than 0.99 (in the matrix). The technique GC-MS SIM mode promoted quantification (criteria of recovery between 70 and 120% and RSD% values of less than 20%) of all pesticides studied. Therefore, concluded that the method proved to be appropriate for multiresidue analysis of pesticides in tomatoes, showing sensitivity and selectivity adequate, and all parameters of validation are according with the limits suggested for validation of chromatographic methods. Samples were collected (n = 33) in the Piracicaba city in local market and the levels of pesticide residues were below the limits of detection for the products analyzed. The products acephate, deltamethrin, difenoconazole and fenpropathrin were evaluated in the GC-MS and showed no sensitivity and selectivity in the chromatographic conditions applied. The implementation of new chromatographic methods for analysis of pesticide residues in food should be encouraged to contribute to efficient monitoring to evaluate the quality and safety of food consumed by the population, identify the sources of contamination and provide an assessment as to the misuse and use unauthorized pesticides
14

A interatividade do canal de retorno no SBTVD com o uso do sinal 2G / The interactivity of the return channel in the ISDB-Tb with the use of the 2G signal

Azevedo, Fábio Henrique de 28 March 2018 (has links)
Submitted by Fábio Henrique de Azevedo (fhazvdo@yahoo.com.br) on 2018-10-09T11:47:48Z No. of bitstreams: 1 Relatório técnico-científico.pdf: 7773319 bytes, checksum: a4494c93c456073f98183f0e5cc7d4ba (MD5) / Rejected by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: 1 - Inserir no corpo do texto a ata de defesa, pois é um ítem obrigatório Agradecemos a compreensão on 2018-10-09T11:59:07Z (GMT) / Submitted by Fábio Henrique de Azevedo (fhazvdo@yahoo.com.br) on 2018-10-09T12:34:34Z No. of bitstreams: 1 Relatório técnico-científico (com ata de defesa e parecer circunstanciado).pdf: 9097240 bytes, checksum: b71a5582e2b7e262dc5c6bca51828641 (MD5) / Rejected by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: 1 - A ficha catalográfica deve ser inserida logo após a folha de rosto 2 - A ata de defesa deve ser inserida logo após a ficha catalográfica. Agradecemos a compreensão on 2018-10-09T13:28:26Z (GMT) / Submitted by Fábio Henrique de Azevedo (fhazvdo@yahoo.com.br) on 2018-10-09T14:43:08Z No. of bitstreams: 1 Relatório técnico-científico (com ficha após folha e ata após ficha).pdf: 8492090 bytes, checksum: df7b797887e36395132db5ba2202de80 (MD5) / Approved for entry into archive by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br) on 2018-10-09T17:19:37Z (GMT) No. of bitstreams: 1 azevedo_fh_me_bauru.pdf: 8492090 bytes, checksum: df7b797887e36395132db5ba2202de80 (MD5) / Made available in DSpace on 2018-10-09T17:19:37Z (GMT). No. of bitstreams: 1 azevedo_fh_me_bauru.pdf: 8492090 bytes, checksum: df7b797887e36395132db5ba2202de80 (MD5) Previous issue date: 2018-03-28 / No Brasil a televisão (TV) de sinal aberto, apesar da sua grande abrangência, vem perdendo espaço para a televisão a cabo e para a internet com conteúdo via fluxo de mídia (streaming). Apesar dos atuais aparelhos de TV serem hoje denominados televisores inteligentes (SmartTV) eles são, na realidade, uma combinação de TV com internet, dependendo de conexão à rede de banda larga e aplicativos de redes sociais para oferecer interatividade na programação de TV aberta. Essa necessidade de outro dispositivo (smartphone, tablet etc.) faz com que as pessoas percam o interesse e deixem de assistir à televisão, pois se distraem com a variedade de funções que tais equipamentos possuem (e-mail, sites de notícias, dentre outros). Os fabricantes de televisores estão aprimorando a qualidade de imagens e sons dos atuais aparelhos de TV e vendem a sensação de se estar dentro dos programas veiculados. Porém, falta ainda um último passo nessa percepção que é o da interação entre os dois lados da tela. O objetivo desta pesquisa foi propor uma solução ao telespectador, trazendo de volta a simplicidade de assistir à televisão, mas com a capacidade de interação já oferecida em alguns programas televisivos através do uso do controle remoto. Portanto, nesta pesquisa técnico-científica propôs-se um novo método para a interatividade televisiva, utilizando a interatividade do canal de retorno ao Sistema Brasileiro de Televisão Digital: com o uso de um cartão inteligente de telefones celulares de tecnologia GSM (cartão SIM) e dos sinais de telecomunicação utilizados no país, buscou-se oferecer uma alternativa para solucionar o problema de interatividade do canal de retorno sem o uso da internet e suas mídias sociais. Como resultado prático deste projeto, é relatado neste relatório técnico-científico o Pedido Nacional de Invenção, o Modelo de Utilidade, o Certificado de Adição de Invenção e entrada na fase nacional do PCT do Instituto Nacional da Propriedade Industrial – INPI para o registro de patente do cartão inteligente. / Despite its massive scope, the market share for analogue TV in Brazil has been decreasing; cable TV and streaming are taking over. Although TV sets are presently referred to as "intelligent devices" (Smart TV), in fact they blend TV programming and internet, thus needing connection with broadband network and social network applications in order to offer interactivity for analogue TV programming. The need for additional equipment (such as a smartphone or a tablet computer) induces viewers not to watch television; for they get distracted by the diversity of options such devices present (email, news websites, etc.). TV set manufacturers are currently improving the quality of its image and sound, making one feel they are within the show; however there is one step missing in this perception: the intercommunication between the two sides of the screen. This study proposes solutions to the viewer, retrieving that feeling of simplicity inherent to watching TV but with the existing interaction offered in some programs by means of the remote control. Therefore, this technical and scientific study introduces a new method of TV interactivity, employing the return channel interactivity to the Brazilian Digital Television System with the SIM card (intelligent card for GSMtechnology cell phones) and the telecommunication signals used in Brazil. This feature may promote a problem-solving alternative concerning the return channel interactivity, without the internet and its social media, however. As a practical result, the National Patent Application, the Utility Model, the Certificate of Addition to Invention and the entry in the national phase of the PCT at the National Institute of Industrial Property (INPI) are here reported, so that the patent to the intelligent card can be registered.
15

Análises multiresíduos de agrotóxicos em tomate (Lycopersicon esculentum Mill) utilizando CG-EM e monitoramento / Multiresidue analysis of pesticides in tomato (Lycopersicon esculentum Mill) using GC-MS and monitoring

Graziela Cristina Rossi de Moura Andrade 23 July 2009 (has links)
A preocupação com os danos provocados à saúde do trabalhador rural e ao meio ambiente devido ao uso indiscriminado de agrotóxicos tem aumentado nos últimos anos. O uso generalizado e intensivo destas substâncias tem gerado diversos problemas relacionados à saúde pública e ao desequilíbrio ambiental, incluindo: intoxicações de agricultores, contaminação de alimentos, água e solos. O tomate é hoje, uma hortaliça bastante conhecida e de elevado consumo no mundo. Sua cultura é bastante afetada por quebras de rendimento e depreciação da qualidade de matéria- prima, em razão da ocorrência de doenças, pragas e estresses abióticos. Apesar da preocupação com o monitoramento dos resíduos de agrotóxicos nos alimentos, poucas metodologias analíticas podem alcançar resultados de alta qualidade simultaneamente para uma gama extensiva de agrotóxicos. No presente estudo, foi desenvolvida e validada a metodologia de análise de multirresíduos QuEChERS (quick, easy, cheap, effective, rugged, and safe) para quantificação de resíduos de agrotóxicos em tomate. Este método provê resultados de forma rápida, fácil, com custo acessível e com alta qualidade. Foram analisados agrotóxicos utilizados principalmente no controle de insetos, sendo: buprofezina, carbofurano, \'alfa\'-endossulfam, \'beta\'-endossulfam, sulfato de endossulfam e monocrotofós. Para isso, realizou-se a fortificação do tomate, previamente homogeneizado, com soluções contendo os agrotóxicos em 3 níveis de fortificação (0,0625; 0,25 e 1,00 mg/Kg). A purificação dos extratos foi realizada através de clean-up dispersivo, e em seguida os extratos foram analisados por CG-EM modo SIM. Neste estudo avaliaram-se os seguintes parâmetros de validação do método: linearidade da curva analítica, sensibilidade, limite de detecção (LD), limite de quantificação (LQ), o efeito matriz, bem como a precisão e a exatidão (em termos de percentual de recuperação). A faixa linear de concentração das curvas analíticas situou-se entre 0,25 a 4,0 ng.\'mü\'L-1 com valores de r2 maiores que 0,99 (na matriz). A técnica CG-EM modo SIM promoveu a quantificação (critérios de recuperação entre 70 e 120% e valores de CV% menores que 20%) de todos os agrotóxicos estudados. Portanto, conclui-se que o método mostrou-se adequado às análises multirresíduos dos agrotóxicos em tomate, apresentando sensibilidade e seletividade adequadas, e todos os parâmetros de validação encontram-se de acordo com os limites sugeridos para validação de métodos cromatográficos. Foram coletadas amostras (n=33) em varejões na cidade de Piracicaba e os níveis residuais de agrotóxicos apresentaram-se abaixo dos limites de detecção para os produtos analisados. Os produtos acefato, deltametrina, difenoconazole e fenpropatrina foram avaliados no sistema CG-EM e não apresentaram sensibilidade e seletividade nas condições cromatográficas aplicadas. A implementação de novos métodos cromatográficos para análise de resíduos de agrotóxicos em alimentos devem ser fomentados para contribuir com o monitoramento eficiente, visando avaliar a qualidade e segurança dos alimentos consumidos pela população, caracterizar as fontes de contaminação e proporcionar uma avaliação quanto ao uso inadequado e não autorizado dos agrotóxicos / The concernment about the damage caused to the health of rural workers and the environment due to indiscriminate use of pesticides has increased in recent years. The commonly and intensive use of these substances has created several problems related to public health and environmental disequilibrium, including poisoning of farmers, contamination of food, water and soil. Nowadays, the tomato is a well known vegetables and high consumption in the world. Its culture is highly affected by loss of yield and depreciation of the quality of raw material, due to the occurrence of diseases, pests and abiotic stresses. Considering the concernment about the monitoring of pesticide residues in food, few analytical methods can achieve high quality results for both a wide range of pesticides. In this study, was developed and validated the methodology of multiresidue analysis QuEChERS (quick, easy, cheap, effective, rugged, and safe) for quantification of residues of pesticides in tomatoes. This method provides results quick, easy, inexpensive and high quality. Were analyzed mainly pesticides used to control insects, are: buprofezina, carbofuran, \'alfa\'-endossulfam, \'beta\'- endossulfam, sulphate endossulfam and monocrotophos. Then, performed a spiking of tomatoes homogenized previously, with solutions containing pesticides, in 3 of fortification levels (0.0625, 0.25 and 1.00 mg/kg). The purification of the extracts was performed by dispersive clean-up, and then the extracts were analyzed by GC-MS using SIM mode. This study evaluated the following parameters for validation of the method: linearity, sensitivity, limit of detection (LOD), limit of quantification (LOQ), matrix effect, precision and accuracy (in terms of percentage of recovery). The linear range of concentration of the analytical curves was between 0.25 to 4.0 ng.\'mü\'L-1 with r2 values of greater than 0.99 (in the matrix). The technique GC-MS SIM mode promoted quantification (criteria of recovery between 70 and 120% and RSD% values of less than 20%) of all pesticides studied. Therefore, concluded that the method proved to be appropriate for multiresidue analysis of pesticides in tomatoes, showing sensitivity and selectivity adequate, and all parameters of validation are according with the limits suggested for validation of chromatographic methods. Samples were collected (n = 33) in the Piracicaba city in local market and the levels of pesticide residues were below the limits of detection for the products analyzed. The products acephate, deltamethrin, difenoconazole and fenpropathrin were evaluated in the GC-MS and showed no sensitivity and selectivity in the chromatographic conditions applied. The implementation of new chromatographic methods for analysis of pesticide residues in food should be encouraged to contribute to efficient monitoring to evaluate the quality and safety of food consumed by the population, identify the sources of contamination and provide an assessment as to the misuse and use unauthorized pesticides
16

Modul elektrické zabezpečovací ústředny s komunikátorem GSM / Module of electronic security central with GSM communicator

Dokulil, Zdeněk January 2010 (has links)
The aim of this diploma thesis is to design and manufacture a small modular burglar alarm control panel with an emphasis on GSM communication functions. The first part of the thesis discusses history of control panels from the first attempts to present technologies. Also a classification of wired and wireless systems is defined. The second part contains an general proposal of the GSM-enabled panel design and description of the circuit. SIM 300C module has been chosen as a GSM terminal device. The final part contains description of key parts of the firmware and a detailed manual for end users. The proposed design has been realized and succesfully tested.
17

Hardware-In-the-Loop simulation of a small scale prototype of a Wave Energy Converter

Magnusson, Anton January 2020 (has links)
Renewable energy sources are a hot topic, both when it comes to climate change and the constant increase in demand of electricity due to population growth and a more electrified society. One such energy source is wave energy - an energy source with great potential but still relatively new with the need for further development. Blekinge Institute of Technology (BTH) together with Ocean Harvesting Technologies (OHT) have made a collaboration to build a scaled Hardware-In-the-Loop (HIL) system of a power take-off (PTO) based on OHTs wave energy converter, InfinityWEC. The purpose is to teach the students at BTH about hydrodynamic and HIL simulations. A manual will also be written to help students perform the lab activities. A model of the HIL system will first be implemented in Matlab/Simulink, both with and without the WEC-Sim hydrodynamic simulation toolbox and simulations will be run to predict the system's behaviour. To parametrize the hydrodynamic model, the open-source Boundary Element Method (BEM) code, NEMOH, is used. The HIL system consists of electric motors, connected mechanically to each other with a coupling. One of the motors is the actuator, which applies torque to the second motor according to the simulated hydrodynamic loads on the buoy. The second motor on the other hand applies a torque according to the load connected to it or torque-controlled according to a selected control strategy. In this thesis two different types of loading is used: 1) resistive load without control of the generator drive, 2) resistive and capacitive load with reactive control of the generator drive. The load resistance can be changed within a limited range as well as the sea state. Data that can be collected are the position and angular velocity of the motors, the currents to and from the two motors and the voltage over the load capacitance. The project concluded that the compensation needed for the motors to get the true hydrodynamic force has little effect when using reactive control and that a protective capacitor is be needed between the actuator motor and the power supply to protect it from reverse current. Finally, this work demonstrated the effectiveness of HIL systems to execute simulations to test and validate PTO systems in wave energy converters. The advantages are that one can create representative wave loading without the presence of water and with ease test different sea states. / Förnybara energikällor är ett hett ämne, både när det gäller klimatförändringar och den ständiga ökningen av efterfrågan av el på grund av befolkningsökning och ett mer elektrifierat samhälle. En sådan energikälla är vågenergi - en energikälla med stor potential men fortfarande relativt ny med behov av vidareutveckling. Blekinge Tekniska Högskola (BTH) vill tillsammans med Ocean Harvesting Technologies (OHT) konstruera ett skalat Hardware-In-The-Loop (HIL) system av power take-off (PTO) baserat på OHT:s vågenergiomvandlare, InfinityWEC. Syftet är att lära eleverna på BTH om hydrodynamik och HIL-simuleringar. En manual kommer också att skrivas för att hjälpa eleverna att utföra labbaktiviteterna. En modell av HIL-systemet kommer först att konstrueras i Matlab/Simulink, både med och utan WEC-Sim hydrodynamisk simuleringsverktygslåda och simuleringar kommer att köras för att förutsäga systemens beteende. För att bestämma de nödvändiga parametrarna för hydrodynamiska modellen används Boundary Element Method koden NEMOH. HIL-systemet består av elmotorer, som är mekaniskt anslutna till varandra med en koppling. En av motorerna är ställdonet, som tillämpar vridmoment på den andra motorn enligt de simulerade hydrodynamiska belastningarna på bojen. Den andra motorn tillämpar ett vridmoment enligt belastningen som är kopplad till den eller är moment reglerad enligt en vald kontrollstrategi. I denna avhandling används två olika typ av belastning: 1) resistiv belastning utan kontroll av generatorndrivdonet, 2) resistiv och kapacitive belastning med reaktiv kontroll av generatorndrivdonet. Belastningsmotståndet kan ändras inom ett visst intervall och lika så havstillståndet. Data som kan samlas in är motorernas position och vinkelhastighet, strömmen till och från de två motorerna och spänningen över last kapasitatorn. I projektet drogs slutsatsen att den kompensation som behövs för motorerna för att få den riktiga hydrodynamiska kraften har liten påverkan reaktiv kontroll används och att det behövs en skyddande kondensator mellan ställdonsmotorn och strömförsörjningen för att skydda den mot bakström. Slutligen visade detta arbete hur effektiva HIL-system är för att utföra simuleringar för att testa och validera PTO-system i vågenergiomvandlare. Fördelarna är att man kan skapa representativ vågbelastning utan närvaro av vatten och med lätthet testa olika havstillstånd.
18

Emprego do método SIM para obtenção das curvas isócronas e de ruptura por fluência / Use of SIM to obtain isochrone and creep rupture curves

Costanzi, Marcio Antonio 03 October 2003 (has links)
A obtenção de resultados de fluência em geossintéticos (isócronas e curva de ruptura por fluência) requer longo tempo de observação e rigoroso controle laboratorial. Dessa forma, muitos produtos disponíveis no mercado brasileiro não foram ensaiados quanto a este fenômeno dificultando sobremaneira a elaboração de projetos mais seguros e econômicos. Há, portanto, a necessidade de estudos não só do fenômeno da fluência em si, mas também de métodos de ensaio que facilitem e acelerem a obtenção das curvas de fluência. Este trabalho apresenta um estudo da fluência de dois geotêxteis não tecidos, um de polipropileno e outro de poliéster, através de ensaios acelerados, utilizando-se o processo denominado Stepped Isothermal Method (SIM). Os valores obtidos pelo método SIM foram comparados aos valores obtidos nos ensaios convencionais, realizados segundo a norma ISO 13431. Os resultados experimentais indicam que os ensaios acelerados, utilizando o método SIM, foram capazes de simular o fenômeno da fluência com boa precisão e, portanto, podem trazer uma grande economia de tempo, além de facilitar e agilizar a caracterização da fluência de geossintéticos. / Creep tests are time consuming and require rigorous laboratory testing control. Because of that many products commercially available in Brazil were not tested regarding this phenomenon. The absence of creep data is an obstacle to the design soil reinforced structures. It is therefore required continuous research effort not only to elucidate creep phenomenon but also to help in the development of test methods that ease and speed up the obtaining of creep curves. This paper presents a creep study carried out on two non-woven geotextiles (PP and PET) using temperature accelerated creep test, namely the Stepped Isothermal Method (SIM). The values obtained using the SIM method were compared to the ones obtained using conventional creep tests following the ISO 13431. The experimental results indicate that the accelerated creep tests, using the SIM method, were capable of simulating the creep phenomenon with good accuracy and, hence, they can bring a great deal of time saving to the characterization of creep in geosynthetics.
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Emprego do método SIM para obtenção das curvas isócronas e de ruptura por fluência / Use of SIM to obtain isochrone and creep rupture curves

Marcio Antonio Costanzi 03 October 2003 (has links)
A obtenção de resultados de fluência em geossintéticos (isócronas e curva de ruptura por fluência) requer longo tempo de observação e rigoroso controle laboratorial. Dessa forma, muitos produtos disponíveis no mercado brasileiro não foram ensaiados quanto a este fenômeno dificultando sobremaneira a elaboração de projetos mais seguros e econômicos. Há, portanto, a necessidade de estudos não só do fenômeno da fluência em si, mas também de métodos de ensaio que facilitem e acelerem a obtenção das curvas de fluência. Este trabalho apresenta um estudo da fluência de dois geotêxteis não tecidos, um de polipropileno e outro de poliéster, através de ensaios acelerados, utilizando-se o processo denominado Stepped Isothermal Method (SIM). Os valores obtidos pelo método SIM foram comparados aos valores obtidos nos ensaios convencionais, realizados segundo a norma ISO 13431. Os resultados experimentais indicam que os ensaios acelerados, utilizando o método SIM, foram capazes de simular o fenômeno da fluência com boa precisão e, portanto, podem trazer uma grande economia de tempo, além de facilitar e agilizar a caracterização da fluência de geossintéticos. / Creep tests are time consuming and require rigorous laboratory testing control. Because of that many products commercially available in Brazil were not tested regarding this phenomenon. The absence of creep data is an obstacle to the design soil reinforced structures. It is therefore required continuous research effort not only to elucidate creep phenomenon but also to help in the development of test methods that ease and speed up the obtaining of creep curves. This paper presents a creep study carried out on two non-woven geotextiles (PP and PET) using temperature accelerated creep test, namely the Stepped Isothermal Method (SIM). The values obtained using the SIM method were compared to the ones obtained using conventional creep tests following the ISO 13431. The experimental results indicate that the accelerated creep tests, using the SIM method, were capable of simulating the creep phenomenon with good accuracy and, hence, they can bring a great deal of time saving to the characterization of creep in geosynthetics.
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Towards nanoscale interconnect for system-on-chip / Approches de mise en oeuvre des nanocommunication pour les réseaux nanocapteurs sans fil et les systèmes sur puce.

Yalgashev, Olimjon 29 October 2015 (has links)
La nanocommunication est un nouveau paradigme qui permet de communiquer à l'échelle nanométrique, via des mécanismes moléculaires, électromagnétiques, acoustiques, ou nano-mécaniques. Le cadre général de cette thèse concerne les réseaux de nanocapteurs sans fil et les nanoréseaux sur puce. Plus précisément, il s'agit des architectures d'interconnexion et des protocoles de communication dans la bande de fréquence des Térahertz. En effet, les architectures réseaux et les protocoles de communication existants doivent être repensés en tenant compte des mécanismes de communication à l'échelle nanométrique.En premier lieu, nous nous sommes focalisés sur la nécessité de développer des approches de diffusion efficaces dans le contexte des réseaux de nanocapteurs sans fil. Une approche de diffusion efficace, issue d'une adaptation d'un protocole de la famille des protocoles d'inondation probabilistes, est présenté et son efficacité et validée par simulations à l'aide de Nano-Sim et NS3.En second lieu, une étude approfondie de l'impact des portées de transmission sur les performances du mécanisme de diffusion basé sur les ondes électromagnétiques à l'échelle nanométrique a été effectuée. Les résultats des simulations montrent que l'adaptation des portées des nano-noeuds permet de contrôler le mécanisme d'inondation et de réduire les redondances des paquets tout en augmentant les débits. Une approche adaptative de sélection de portées de transmission contrôlée au niveau des nano-noeuds est proposée. En dernier lieu, nous nous sommes attaqués à un troisième défi en examinant ce nouveau paradigme de nanocommunication dans le contexte de la conception des nanoréseaux sur puce (Network on Chip, NoC). / Nanocommunication is a new paradigm that enables connectivity at the nanoscale through molecular, electromagnetic, acoustic, or nanomechanical mechanisms. The general context of this thesis concerns wireless nanosensor networks and nanonetworks on chips. More precisely, the thesis deals with interconnection architectures and communication protocols in the terahertz band. The existing network architectures and communication protocols should be revisited taking into account the communication mechanisms at the nanoscale.First, dissemination approaches in the context of wireless nanosensor networks are addressed. An efficient broadcasting approach is presented and the simulation performance results with Nano-Sim and NS3 show that the proposed scheme is superior to flooding, especially in the cases of excessive broadcasts.Second, we investigated the impact of transmission ranges on the performance of broadcast mechanisms based on electromagnetic waves at the nanoscale. Adaptive transmission range of electromagnetic-based communication approaches are proposed. Simulations are conducted with fixed and adaptive transmission ranges to show the efficiency of the proposed approaches in terms of throughput and latency according to the network density.The third part addresses the hypothesis of using EM-based nanonetwok as an on-chip interconnect for SoCs.

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