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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

Harmful Algal Blooms of the West Florida Shelf and Campeche Bank: Visualization and Quantification using Remote Sensing Methods

Soto Ramos, Inia Mariel 01 January 2013 (has links)
Harmful Algal Blooms (HABs) in the Gulf of Mexico (GOM) are natural phenomena that can have negative impacts on marine ecosystems on which human health and the economy of some Gulf States depends. Many of the HABs in the GOM are dominated by the toxic dinoflagellate Karenia brevis. Non-toxic phytoplankton taxa such as Scrippsiella sp. also form intense blooms off the Mexican coast that result in massive fish mortality and economic losses, particularly as they may lead to anoxia. The main objectives of this dissertation were to (1) evaluate and improve the techniques developed for detection of Karenia spp. blooms on the West Florida Shelf (WFS) using satellite remote sensing methods, (2) test the use of these methods for waters in the GOM, and (3) use the output of these techniques to better understand the dynamics and evolution of Karenia spp. blooms in the WFS and off Mexico. The first chapter of this dissertation examines the performance of several Karenia HABs detection techniques using Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images and historical ground truth observations collected on the WFS from August 2002 to December 2011. A total of 2323 in situ samples collected by the Florida Fish and Wildlife Research Institute to test for Karenia spp. matched pixels with valid ocean color satellite observations over this period. This dataset was used to systematically optimize variables and coefficients used in five published HAB detection methods. Each technique was tested using a set of metrics that included the F-Measure (FM). Before optimization, the average FM for all techniques was 0.47. After optimization, the average FM increased to 0.59, and false positives decreased ~50%. The addition of a Fluorescence Line Height (FLH) criterion improved the performance of every method. A new practical method was developed using a combination of FLH and Remote Sensing Reflectance at 555 nm (Rrs555-FLH). The new method resulted in an FM of 0.62 and 3% false negatives, similar to those from more complex techniques. The first chapter concludes with a series of recommendations on how to improve the detection techniques and how to take these results a step further into a Gulf wide observing systems for HABs. In chapter two, ocean color techniques were used to examine the extension, evolution and displacement of four Karenia spp. events that occurred in the WFS between 2004 and 2011. Blooms were identified in the imagery using the new Rrs-FLH method and validated using in situ phytoplankton cell counts. The spatial extension of each event was followed in time by delineating the blooms. In 2004 and 2005, the WFS was affected by a series of hurricanes that led to high river discharge and intense sediment resuspension events. Both processes had an impact on HAB occurrence. For example, I tracked a Karenia spp. bloom found in late December 2004 approximately 40-80 km offshore Saint Petersburg, which then expanded reaching an extension of >8000 km2 in February 2005. The bloom weakened in spring 2005 and intensified again in summer reaching >42,000 km2 after the passage of hurricane Katrina in August 2005. This bloom covered the WFS from Charlotte Harbor to the Florida Panhandle. Two other cases were studied in the WFS. The results of the Hybrid Coordinate Ocean Model from the U.S. Navy aid understanding the dispersal of the blooms. During fall 2011, three field campaigns to study HABs in Mexico were conducted to do an analysis of optical properties and explore the possibility of using ocean color techniques to distinguish between the main phytoplankton blooms in that region. Three main bloom scenarios were observed in the Campeche Bank region: massive diatom blooms, blooms dominated by Scrippsiella spp., and Karenia spp. blooms. The normalized specific phytoplankton absorption spectra were found to be different for Karenia spp. and Scrippsiella sp. blooms. A new technique that combines phytoplankton absorption derived from MODIS data and the new technique developed in Chapter One showed potential for a detection technique that can distinguish between Karenia and Scrippsiella blooms. Additional work is needed to improve the new technique developed for Mexican waters, but results show potential for detection techniques that can be used Gulf-wide. This will help better understand the dynamic and possible connectivity of phytoplankton blooms in the GOM.
12

Proposal of two solutions to cope with the faulty behavior of circuits in future technologies

Rhod, Eduardo Luis January 2007 (has links)
A diminuição no tamanho dos dispositivos nas tecnologias do futuro traz consigo um grande aumento na taxa de erros dos circuitos, na lógica combinacional e seqüencial. Apesar de algumas potenciais soluções começarem a ser investigadas pela comunidade, a busca por circuitos tolerantes a erros induzidos por radiação, sem penalidades no desempenho, área ou potência, ainda é um assunto de pesquisa em aberto. Este trabalho propõe duas soluções para lidar com este comportamento imprevisível das tecnologias futuras: a primeira solução, chamada MemProc, é uma arquitetura baseada em memória que propõe reduzir a taxa de falhas de aplicações embarcadas micro-controladas. Esta solução baseia-se no uso de memórias magnéticas, que são tolerantes a falhas induzidas por radiação, e área de circuito combinacional reduzida para melhorar a confiabilidade ao processar quaisquer aplicações. A segunda solução proposta aqui é uma implementação de um IP de infra-estrutura para o processador MIPS indicada para sistemas em chip confiáveis, devido a sua adaptação rápida e por permitir diferentes níveis de robustez para a aplicação. A segunda solução é também indicada para sistemas em que nem o hardware nem o software podem ser modificados. Os resultados dos experimentos mostram que ambas as soluções melhoram a confiabilidade do sistema que fazem parte com custos aceitáveis e até, no caso da MemProc, melhora o desempenho da aplicação. / Device scaling in new and future technologies brings along severe increase in the soft error rate of circuits, for combinational and sequential logic. Although potential solutions are being investigated by the community, the search for circuits tolerant to radiation induced errors, without performance, area, or power penalties, is still an open research issue. This work proposes two solutions to cope with this unpredictable behavior of future technologies: the first solution, called MemProc, is a memory based architecture proposed to reduce the fault rate of embedded microcontrolled applications. This solution relies in the use magnetic memories, which are tolerant to radiation induced failures, and reduced combinational circuit area to improve the reliability when processing any application. The second solution proposed here is an infrastructure IP implementation for the MIPS architecture indicated for reliable systems-on-chip due to its fast adaptation and different levels of application hardening that are allowed. The second solution is also indicated for systems where neither the hardware nor the software can be modified. The experimental results show that both solutions improve the reliability of the system they take part with affordable overheads and even, as in the case of the MemProc solution, improving the performance results.
13

Quaternary CLB a falul tolerant quaternary FPGA

Rhod, Eduardo Luis January 2012 (has links)
A diminuição no tamanho dos transistores vem aumentando cada vez mais o número de funções que os dispositivos eletrônicos podem realizar. Apesar da diminuição do tamanho mínimo dos transistores, a velocidade máxima dos circuitos não consegue seguir a mesma taxa de aumento. Um dos grandes culpados apontados pelos pesquisadores são as interconexões entre os transistores e também entre os componentes. O aumento no número de interconexões dos circuitos traz consigo um significativo aumento do cosumo de energia, aumento do atraso de propagação dos sinais, além de um aumento da complexidade e custo do projeto dos circuitos integrados. Como uma possível solução a este problema é proposta a utilização de lógica multivalorada, mais especificamente, a lógica quaternária. Os dispositivos FPGAs são caracterizados principalmente pela grande flexibilidade que oferecem aos projetistas de sistemas digitais. Entretanto, com o avanço nas tecnologias de fabricação de circuitos integrados e diminuição das dimensões de fabricação, os problemas relacionados ao grande número de interconexões são uma preocupação para as próximas tecnologias de FPGAs. As tecnologias menores que 90nm possuem um grande aumento na taxa de erros dos circuitos, na lógica combinacional e sequencial. Apesar de algumas potenciais soluções começara a ser investigadas pela comunidade, a busca por circuitos tolerantes a erros induzidos por radiação, sem penalidades no desempenho, área ou potência, ainda é um assunto de pesquisa em aberto. Este trabalho propõe o uso de circuitos quaternários com modificações para tolerar falhas provenientes de eventos transientes. Como principal contribuição deste trabalho destaca-se o desenvolvimento de uma CLB (do inglês Configurable Logic Block) quaternária capaz de suportar eventos transientes e, na possibilidade de um erro, evitá-lo ou corrigi-lo. / The decrease in transistor size is increasing the number of functions that can be performed by the electronic devices. Despite this reduction in the transistors minimum size, the circuit’s speed does not follow the same rate. One of the major reasons pointed out by researchers are the interconnections between the transistors and between the components. The increase in the number of circuit interconnections brings a significant increase in energy consumption, propagation delay of signals, and an increase in the complexity and cost of new technologies IC designs. As a possible solution to this problem the use of multivalued logic is being proposed, more specifically, the quaternary logic. FPGA devices are characterized mainly by offering greater flexibility to designers of digital systems. However, with the advance in IC manufacturing technologies and the reduced size of the minimum fabricated dimensions, the problems related to the large number of interconnections are a concern for future technologies of FPGAs. The sub 90nm technologies have a large increase in the error rate of its functions for the combinational and sequential logic. Although potential solutions are being investigated by the community, the search for circuits tolerant to radiation induced errors, without performance, area, or power penalties, is still an open research issue. This work proposes the use of quaternary circuits with modifications to tolerate faults from transient events. The main contribution of this work is the development of a quaternary CLB (Configurable Logic Block) able to withstand transient events and the occurrence of soft errors.
14

Proposal of two solutions to cope with the faulty behavior of circuits in future technologies

Rhod, Eduardo Luis January 2007 (has links)
A diminuição no tamanho dos dispositivos nas tecnologias do futuro traz consigo um grande aumento na taxa de erros dos circuitos, na lógica combinacional e seqüencial. Apesar de algumas potenciais soluções começarem a ser investigadas pela comunidade, a busca por circuitos tolerantes a erros induzidos por radiação, sem penalidades no desempenho, área ou potência, ainda é um assunto de pesquisa em aberto. Este trabalho propõe duas soluções para lidar com este comportamento imprevisível das tecnologias futuras: a primeira solução, chamada MemProc, é uma arquitetura baseada em memória que propõe reduzir a taxa de falhas de aplicações embarcadas micro-controladas. Esta solução baseia-se no uso de memórias magnéticas, que são tolerantes a falhas induzidas por radiação, e área de circuito combinacional reduzida para melhorar a confiabilidade ao processar quaisquer aplicações. A segunda solução proposta aqui é uma implementação de um IP de infra-estrutura para o processador MIPS indicada para sistemas em chip confiáveis, devido a sua adaptação rápida e por permitir diferentes níveis de robustez para a aplicação. A segunda solução é também indicada para sistemas em que nem o hardware nem o software podem ser modificados. Os resultados dos experimentos mostram que ambas as soluções melhoram a confiabilidade do sistema que fazem parte com custos aceitáveis e até, no caso da MemProc, melhora o desempenho da aplicação. / Device scaling in new and future technologies brings along severe increase in the soft error rate of circuits, for combinational and sequential logic. Although potential solutions are being investigated by the community, the search for circuits tolerant to radiation induced errors, without performance, area, or power penalties, is still an open research issue. This work proposes two solutions to cope with this unpredictable behavior of future technologies: the first solution, called MemProc, is a memory based architecture proposed to reduce the fault rate of embedded microcontrolled applications. This solution relies in the use magnetic memories, which are tolerant to radiation induced failures, and reduced combinational circuit area to improve the reliability when processing any application. The second solution proposed here is an infrastructure IP implementation for the MIPS architecture indicated for reliable systems-on-chip due to its fast adaptation and different levels of application hardening that are allowed. The second solution is also indicated for systems where neither the hardware nor the software can be modified. The experimental results show that both solutions improve the reliability of the system they take part with affordable overheads and even, as in the case of the MemProc solution, improving the performance results.
15

Exposition aux bactéries environnementales dans l’habitat : méthodes de mesure et impacts sur la santé des occupants / Exposure to the environmental bacteria in the housing environment : methods of measure and impacts on the health of the occupants

Guenoune, Yanis 21 December 2017 (has links)
La qualité de l’air des environnements intérieurs est essentielle pour la santé. Le manque de renouvellement d’air et l’humidité dans les habitats favorise la prolifération microbienne. Les effets sur la santé sont multiples et souvent associés à des maladies chroniques respiratoires, tel que l’asthme. Ces effets sont plus ou moins graves selon le niveau d’exposition et la vulnérabilité des occupants et le rôle des moisissures est pointé. Cependant, le manque d’outils valides permettant d’évaluer quantitativement l’exposition aux bactéries environnementales constitue une des principales difficultés pour mieux appréhender leur impact sur la santé humaine. Un protocole expérimental basé sur les techniques culturales a été développé et testé au laboratoire pour mesurer la survie des bactéries dans des poussières domestiques collectées au sol. L’analyse de ces poussières a permis de déterminer le temps de survie des bactéries testées. Cependant, les méthodes culturales actuelles sont limitées et n’apportent pas assez d’informations sur la composition de la flore bactérienne dans l’habitat. L’utilisation des méthodes moléculaires, tel que le séquençage haut débit, est nécessaire pour y remédier. Par ailleurs, les poussières domestiques pourraient constituer un substrat intégrateur de l’exposition chronique des occupants. Outre le développement, la standardisation, et la validation d’outils de mesure, une approche globale de sensibilisation et de prévention du risque d’exposition aux contaminants des environnements intérieurs est recommandée, en particulier chez les populations vulnérables. / Indoor air quality is essential for health. Lack of ventilation and presence of humidity in habitats promotes microbial growth. The health effects are multiple and often associated with chronic respiratory diseases, such as asthma. These effects are more or less serious depending on the level of exposure and the vulnerability of occupants and the role of mold is pointed out. However, the lack of valid tools for quantitatively assessing exposure to environmental bacteria is one of the main difficulties in better understanding their impact on human health. An experimental protocol based on cultural techniques was developed and tested in the laboratory to measure the survival of bacteria in domestic dust collected on the ground. The analysis of these dusts made it possible to determine the survival time of the bacteria tested. However, current culture methods are limited and do not provide enough information on the composition of the bacterial flora in the habitat. The use of molecular methods, such as high throughput sequencing, is needed to address this. In addition, domestic dust could be an integrating substrate for chronic occupant exposure. In addition to the development, standardization, and validation of measurement tools, a comprehensive approach to raising awareness and preventing the risk of indoor exposure to contaminants is recommended, particularly for vulnerable populations.
16

Quaternary CLB a falul tolerant quaternary FPGA

Rhod, Eduardo Luis January 2012 (has links)
A diminuição no tamanho dos transistores vem aumentando cada vez mais o número de funções que os dispositivos eletrônicos podem realizar. Apesar da diminuição do tamanho mínimo dos transistores, a velocidade máxima dos circuitos não consegue seguir a mesma taxa de aumento. Um dos grandes culpados apontados pelos pesquisadores são as interconexões entre os transistores e também entre os componentes. O aumento no número de interconexões dos circuitos traz consigo um significativo aumento do cosumo de energia, aumento do atraso de propagação dos sinais, além de um aumento da complexidade e custo do projeto dos circuitos integrados. Como uma possível solução a este problema é proposta a utilização de lógica multivalorada, mais especificamente, a lógica quaternária. Os dispositivos FPGAs são caracterizados principalmente pela grande flexibilidade que oferecem aos projetistas de sistemas digitais. Entretanto, com o avanço nas tecnologias de fabricação de circuitos integrados e diminuição das dimensões de fabricação, os problemas relacionados ao grande número de interconexões são uma preocupação para as próximas tecnologias de FPGAs. As tecnologias menores que 90nm possuem um grande aumento na taxa de erros dos circuitos, na lógica combinacional e sequencial. Apesar de algumas potenciais soluções começara a ser investigadas pela comunidade, a busca por circuitos tolerantes a erros induzidos por radiação, sem penalidades no desempenho, área ou potência, ainda é um assunto de pesquisa em aberto. Este trabalho propõe o uso de circuitos quaternários com modificações para tolerar falhas provenientes de eventos transientes. Como principal contribuição deste trabalho destaca-se o desenvolvimento de uma CLB (do inglês Configurable Logic Block) quaternária capaz de suportar eventos transientes e, na possibilidade de um erro, evitá-lo ou corrigi-lo. / The decrease in transistor size is increasing the number of functions that can be performed by the electronic devices. Despite this reduction in the transistors minimum size, the circuit’s speed does not follow the same rate. One of the major reasons pointed out by researchers are the interconnections between the transistors and between the components. The increase in the number of circuit interconnections brings a significant increase in energy consumption, propagation delay of signals, and an increase in the complexity and cost of new technologies IC designs. As a possible solution to this problem the use of multivalued logic is being proposed, more specifically, the quaternary logic. FPGA devices are characterized mainly by offering greater flexibility to designers of digital systems. However, with the advance in IC manufacturing technologies and the reduced size of the minimum fabricated dimensions, the problems related to the large number of interconnections are a concern for future technologies of FPGAs. The sub 90nm technologies have a large increase in the error rate of its functions for the combinational and sequential logic. Although potential solutions are being investigated by the community, the search for circuits tolerant to radiation induced errors, without performance, area, or power penalties, is still an open research issue. This work proposes the use of quaternary circuits with modifications to tolerate faults from transient events. The main contribution of this work is the development of a quaternary CLB (Configurable Logic Block) able to withstand transient events and the occurrence of soft errors.
17

Proposal of two solutions to cope with the faulty behavior of circuits in future technologies

Rhod, Eduardo Luis January 2007 (has links)
A diminuição no tamanho dos dispositivos nas tecnologias do futuro traz consigo um grande aumento na taxa de erros dos circuitos, na lógica combinacional e seqüencial. Apesar de algumas potenciais soluções começarem a ser investigadas pela comunidade, a busca por circuitos tolerantes a erros induzidos por radiação, sem penalidades no desempenho, área ou potência, ainda é um assunto de pesquisa em aberto. Este trabalho propõe duas soluções para lidar com este comportamento imprevisível das tecnologias futuras: a primeira solução, chamada MemProc, é uma arquitetura baseada em memória que propõe reduzir a taxa de falhas de aplicações embarcadas micro-controladas. Esta solução baseia-se no uso de memórias magnéticas, que são tolerantes a falhas induzidas por radiação, e área de circuito combinacional reduzida para melhorar a confiabilidade ao processar quaisquer aplicações. A segunda solução proposta aqui é uma implementação de um IP de infra-estrutura para o processador MIPS indicada para sistemas em chip confiáveis, devido a sua adaptação rápida e por permitir diferentes níveis de robustez para a aplicação. A segunda solução é também indicada para sistemas em que nem o hardware nem o software podem ser modificados. Os resultados dos experimentos mostram que ambas as soluções melhoram a confiabilidade do sistema que fazem parte com custos aceitáveis e até, no caso da MemProc, melhora o desempenho da aplicação. / Device scaling in new and future technologies brings along severe increase in the soft error rate of circuits, for combinational and sequential logic. Although potential solutions are being investigated by the community, the search for circuits tolerant to radiation induced errors, without performance, area, or power penalties, is still an open research issue. This work proposes two solutions to cope with this unpredictable behavior of future technologies: the first solution, called MemProc, is a memory based architecture proposed to reduce the fault rate of embedded microcontrolled applications. This solution relies in the use magnetic memories, which are tolerant to radiation induced failures, and reduced combinational circuit area to improve the reliability when processing any application. The second solution proposed here is an infrastructure IP implementation for the MIPS architecture indicated for reliable systems-on-chip due to its fast adaptation and different levels of application hardening that are allowed. The second solution is also indicated for systems where neither the hardware nor the software can be modified. The experimental results show that both solutions improve the reliability of the system they take part with affordable overheads and even, as in the case of the MemProc solution, improving the performance results.
18

Užmaskuoto kenkėjiško programinio kodo tinklalapiuose aptikimas pagal jo savybes / Detection of malicious obfuscated code in websites using its characteristics

Ladyga, Linas 20 June 2011 (has links)
Darbo tikslas – sudaryti ir praktiškai realizuoti metodą užmaskuoto kenkėjiško programinio kodo tinklalapiuose aptikimui pagal jo savybes. Darbe nagrinėjamos tinklalapiuose talpinamo užmaskuoto kenkėjiško kodo aptikimo problemos. Išanalizuoti kenkėjiško kodo maskavimo metodai ir jo savybės. Aprašytas užmaskuoto JavaScript kodo aptikimo metodas, paremtas nustatytomis užmaskuoto kodo savybėmis ir pagal jas aprašytais paieškos kriterijais: žodžio ilgiu, simbolių skaičiumi žodyje ir simbolių dažniu žodyje. Metodas pristatytas pranešime 14-oje Lietuvos jaunųjų mokslininkų konferencijoje „Mokslas - Lietuvos ateitis“, įvykusioje Vilniuje 2011 m. balandžio 15 d. Remiantis šiuo metodu atliktas tyrimas, kurio rezultatai rodo pasiūlyto metodo veiksmingumą – pasiektas 98% užmaskuoto kodo aptikimo tinklalapiuose tikslumas. Tyrimo rezultatai paskelbti straipsnyje, kuris priimtas spausdinimui recenzuojamame periodiniame mokslo žurnale „Jaunųjų mokslininkų darbai“. Darbą sudaro: įvadas, 6 skyriai, išvados, literatūros sąrašas, priedai. Darbo apimtis – 55 p. teksto be priedų, 23 iliustr., 4 lent., 44 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai. / The aim of this thesis is to suggest and practically implement a method of malicious obfuscated code detection using its characteristics. In this thesis we analyze problems of obfuscated malicious code detection in websites, malicious code obfuscation techniques and obfuscated code characteristics. In this paper suggested method of malicious obfuscated code detection in websites using its characteristics is described. Method is based on three search characteristics: word size, number of characters in word and frequency of particular characters. Method was presented in the 14th Conference for Lithuania Junior Researchers SCIENCE FOR FUTURE held in Vilnius, April 15, 2011. An experiment based on this study was made. Results show the effectiveness of the proposed method – 98% accuracy of obfuscated code detection in websites was reached. Experiment results were published in an article, which is being published in a reviewed periodical academic journal "Young Scientists". Structure: introduction, 6 chapters, conclusions and suggestions, references. Thesis consists of – 55 p. text without appendixes, 23 pictures, 4 tables, 44 bibliographical entries. Appendixes included.
19

Estudo comparativo de técnicas para Diagnóstico de falhas em motores de Indução trifásicos

Nóbrega Sobrinho, Carlos Alberto 31 August 2015 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2017-05-22T15:08:58Z No. of bitstreams: 1 arquivo total.pdf: 10123779 bytes, checksum: a9bc3c38b693c977dc116bf2cde4af83 (MD5) / Made available in DSpace on 2017-05-22T15:08:58Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 10123779 bytes, checksum: a9bc3c38b693c977dc116bf2cde4af83 (MD5) Previous issue date: 2015-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Electrical motors are responsible for 95% of primary movement source in industrialized nations. Among those, 90% are Three-Phase Induction Motors, present in almost all industrial sectors. Due to its importance on this sector, there is a need for monitoring them in order to avoid production stops and operational disasters. In this work, studies were conducted on common fault diagnostics in Three-Phase Induction Motors intending industrial applications. Different sensoring techniques were used and their performance were analyzed. An embedded system was developed to make field applications with different techniques possible. This installation can be done noninvasively and data collection can be obtained in real time. Fast Fourier Transform (FFT) and wavelet processing techniques are used as tools in mathematical processing of the data. In the first moment, fault analyses were conducted offline making use of data acquisition devices and further processing of the information. In a second phase, the embedded system was used to monitor automatically (online) the evolution of the damage developed. The system receives the motor current signal, and using local processing, conducts the spectral analysis of the signal identifying incipient faults. These data are available for communication with or without wires. For the embedded system implementation, the algorithms were adjusted to comply with the embedded hardware resources restrictions. Through theoretical and experimental development, several techniques were used and compared with the objective of performing a full diagnostic TIM malfunction. The experimental results corroborate the theoretical ones, and it was conducted a detailed study of the methods on the state of the art and new approaches were made. / industrializadas. Desses, 90% são motores de indução trifásicos (MIT), estando presentes em praticamente todos os setores industriais. Devido a sua importância no setor produtivo, existe a necessidade que os mesmos sejam devidamente monitorados evitando interrupções na produção e desastres operacionais. Nesse trabalho foram realizados estudos para diagnósticos de falhas comuns em motores de indução trifásicos visando aplicação industrial. As diferentes técnicas de sensoriamento foram utilizadas e o desempenho de cada método foi analisado. Um sistema embarcado foi desenvolvido com o intuito de se viabilizar as aplicações em campo, cuja instalação pode ser realizada de forma não invasiva e as informações podem ser obtidas em tempo real. A Transformadas Rápida de Fourier (FFT) e as técnicas de processamento wavelet serão utilizadas como ferramentas matemáticas no tratamento dos dados. Em um primeiro momento, as análises das falhas foram feitas de forma off-line, fazendo uso de placas de aquisição de dados e um posterior tratamento das informações. Em um segundo momento, foi desenvolvido o sistema embarcado que faz um monitoramento automático (online) da evolução da avaria, que recebe o sinal de corrente do motor e, utilizando processamento local, faz a análise espectral do sinal identificando falhas incipientes. Esses dados ficam disponíveis (off line e on line) por comunicação com ou sem fios. Para a implementação do sistema embarcado, os algoritmos foram ajustados de modo a respeitar as restrições de recursos do hardware embarcado. Através de desenvolvimento teórico e experimental, várias técnicas foram utilizadas e comparadas com o objetivo de se realizar um diagnóstico completo de avaria de MIT. Os resultados experimentais corroboram com os teóricos e foi realizado um estudo aprofundado dos métodos do estado da arte e novas abordagens foram realizadas.
20

Ubiquitination assays and protein-protein interactions of E3 ligase CHIP.

De Silva, Anthony Ruvindi Iroshana 06 July 2023 (has links)
No description available.

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