• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 60
  • 36
  • 22
  • 17
  • 8
  • 8
  • 5
  • 3
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 199
  • 38
  • 21
  • 21
  • 17
  • 16
  • 14
  • 13
  • 12
  • 12
  • 11
  • 11
  • 10
  • 10
  • 10
  • 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

Rapid Identification Of Aspergillus Spp. Using A Pcr Based Melting Curve Method And Characterization Of A Novel Chitinase In Insect Resistant Maize Lines

Wu, Biing-Ru 11 December 2009 (has links)
Identification of fungal isolates is critical in studying Aspergillus flavus ecology and for developing methods to reduce aflatoxin contamination. In our efforts to track biocontrol applications of the atoxigenic A. flavus K49 (NRRL 30797), we have developed a rapid and accurate classification system for A. flavus based on PCR product melting temperatures (Tm). Using 18 primers and a total of 59 Aspergilli strains, including all 49 representatives of the Georgian peanut Vegetative Compatibility Groups (VCGs), a decision tree Tm flowchart was generated. The decision tree can classify all 59 strains using only 9 of the SSR primers and an average of 3.4 primers for each definitive classification. To confirm the effectiveness of the decision tree for strain identification, unknown samples isolated from experimental fields inoculated with various A. flavus strains in Stoneville, MS were analyzed. Ninety-six percent of the samples could be placed into a VCG using Tm(s) coupled with the decision tree. This dynamic system is an excellent tool for researchers studying biodiversity of A. flavus.
12

Design and Analysis of LOOM based a-ZnO Optical Waveguide Sensors

Srinivasan, Aarthi 25 April 2011 (has links)
No description available.
13

Landsat TM-Based Forest Area Estimation Using Iterative Guided Spectral Class Rejection

Wayman, Jared Paul 26 May 2000 (has links)
In cooperation with the USDA Forest Service Southern Research Station, an algorithm has been developed to replace the current aerial-photography-derived FIA Phase 1 estimates of forest/non-forest with a Landsat Thematic Mapper-based forest area estimation. Corrected area estimates were obtained using a new hybrid classifier called Iterative Guided Spectral Class Rejection (IGSCR) for portions of three physiographic regions of Virginia. Corrected area estimates were also derived using the Landsat Thematic Mapper-based Multi-Resolution Land Characteristic Interagency Consortium (MRLC) cover maps. Both satellite-based corrected area estimates were tested against the traditional photo-based estimates. Forest area estimates were not significantly different (at the 95% level) between the traditional FIA, IGSCR, and MRLC methods, although the precision of the satellite-based estimates was lower. The estimated percent forest area and the standard error (respectively) of the estimates for each region and method are as follows; Coastal Plain- Phase 1 66.06% and 1.08%, IGSCR 68.88% and 2.93%, MRLC 69.84% and 3.08%. Piedmont- Phase 1 63.87% and 1.91%, IGSCR 65.52% and 3.50%, MRLC 59.19% and 3.83%. Ridge and Valley- Phase 1 69.74% and 1.22%, IGSCR 70.02%, and 2.43%, MRLC 70.53% and 2.52%. Map accuracies were not significantly different (at the 95% level) between the IGSCR method and the MRLC method. Overall accuracies ranged from 80% to 89% using FIA definitions of forest and non-forest land use. Given standardization of the image rectification process and training data properties, the IGSCR methodology is objective and repeatable across users, regions, and time and outperforms the MRLC for FIA applications. / Master of Science
14

Estudo de desempenho de ferramenta computacional no cálculo da luz natural em edificações para a cidade de Juiz de Fora

São José, Juliana Amaral de 02 June 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-05-26T12:43:06Z No. of bitstreams: 1 julianaamaraldesaojose.pdf: 7938285 bytes, checksum: d9d0facf478a36117953b78e547880e2 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-26T13:17:13Z (GMT) No. of bitstreams: 1 julianaamaraldesaojose.pdf: 7938285 bytes, checksum: d9d0facf478a36117953b78e547880e2 (MD5) / Made available in DSpace on 2017-05-26T13:17:13Z (GMT). No. of bitstreams: 1 julianaamaraldesaojose.pdf: 7938285 bytes, checksum: d9d0facf478a36117953b78e547880e2 (MD5) Previous issue date: 2015-06-02 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / A demanda crescente do mercado da construção civil por edificações que possuam baixo consumo energético exige, a cada dia, respostas rápidas e soluções de projeto eficientes. O uso de software na elaboração do projeto aperfeiçoa cada vez mais este processo. O objetivo dessa pesquisa foi conhecer a melhor aplicabilidade e usabilidade do software AutodeskR EcotectTM Analysis no processo de projeto, em relação à contribuição da luz natural no ambiente construído. O referido software se apresenta como uma alternativa para auxiliar a análise de conforto durante as primeiras etapas da elaboração do projeto. Para sua análise, foram cruzados os resultados de simulações computacionais e resultados obtidos através de medições feitas no local de estudo. A contribuição após a aferição de resultados deste trabalho, está na demonstração da adequação e usabilidade de softwares de simulação na otimização do processo de projeto. Assim, este estudo nos mostra a melhor aplicabilidade do software no que diz respeito à influência da iluminação natural na concepção arquitetônica. Este processo de usabilidade e desempenho do software pode proporcionar o desenvolvimento de novas metodologias de trabalho para o processo projetual. / The increasing market of low energy building constructions demand new efficiency projects and quickly solutions. The AutodeskR EcotectTM Analysis software allows the evaluation of comfort during the early stages of project design. The aim of this research was to evaluate the software performance on the architectural project concerning the daylighting. A sequence of methodological analyses were performed to compare results from computational simulation and collected data from the study site. According to the results is possible to prove the suitability and usability of the software in the project optimization. This work shows the optimization of the software concerning the effect of daylighting on the architectonic conception. The performance and adequacy of the software leads to the development of new strategies for the design process.
15

Network Design Considerations in Telemetry Systems

Grebe, Andy, Klein, Wayne 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / In today’s world, computer networking has become common place both in industry as well as home, however all networks are not the same! The Telemetry world, like with many industries, has critical design considerations that need to be evaluated when you begin a new system or just adding on to a current infrastructure. This paper is intended to outline needed considerations when planning or implementing a network design in Telemetry Systems. These applications can range from sensor data transport through High Definition/High Speed Video applications.
16

Avalia??o do comportamento de degrada??o de Blenda de PEBD com aditivo PEPZYME(TM)

Miranda, Gabriela Messias 24 November 2017 (has links)
Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2017-12-11T15:49:59Z No. of bitstreams: 1 Disserta??o Gabriela Messias Miranda.pdf: 10446144 bytes, checksum: 5a93d29a212d33d004ce8c576f23db33 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-12-18T10:43:52Z (GMT) No. of bitstreams: 1 Disserta??o Gabriela Messias Miranda.pdf: 10446144 bytes, checksum: 5a93d29a212d33d004ce8c576f23db33 (MD5) / Made available in DSpace on 2017-12-18T10:50:02Z (GMT). No. of bitstreams: 1 Disserta??o Gabriela Messias Miranda.pdf: 10446144 bytes, checksum: 5a93d29a212d33d004ce8c576f23db33 (MD5) Previous issue date: 2017-11-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Low density polyethylene (LDPE) was mixed with the PEPZYMETM commercial additive in order to prepare a blend with biodegradation behavior, therefore was added 8% of the commercial additive (PE8), once that the PE is a material of high resistance to degradation. Due to this property, processability and low cost, LDPE is a plastic very used in various applications, mostly in packaging. Beside biodegradation, it is important evaluate your abiotic degradation. For that, it was realized a accelerated aging assay for 1000 h with cycles of 8h of UVA radiation in 60 ?C and cycles of 4 h of condensation in 50 ?C, to evaluate the behavior of this material front weathering. After the pure PE samples (PE0) and with additive were removed to each 200h and characterized, in order to identify the changes in the chemical properties, physical, mechanical, thermal and morphological, caused through the additive effect as well as weathering effect. The results of this study showed that the aging provoke changes in the structural characteristics (insertion of functional groups) and morphological (appearance of microcracks and increase of th roughness), mechanical (increase of the stiffness and loss of plasticity) and thermal (increase of the crystallinity degree and of the range of thermal degradation) properties; being this changes very attractive for the microorganisms when the exposed materials were put in contact with the soil. The presence of the additive in the PE matrix helped in the aging process, once that functional groups were added in the chemical structure of LDPE. The C, H, N contents and carbonyl indexes of the samples were of according with the FTIR spectrums. The C:N ratios of PE8 and PE8/env presented the expected behavior in the literature (decrease of this value) for the occurrence of decomposition process. / Polietileno de baixa densidade (PEBD) foi misturado com o aditivo comercial PEPZYMETM a fim de preparar uma blenda com comportamento de biodegrada??o, para tanto foi adicionado 8% do aditivo comercial (PE8), uma vez que o PE ? um material de alta resist?ncia a degrada??o. Devido a esta propriedade, processabilidade e seu baixo custo, o PEBD ? um pl?stico muito utilizado em diversas aplica??es, principalmente em embalagens. Al?m da biodegrada??o, ? importante avaliar ? sua degrada??o abi?tica. Para isso foi realizado um ensaio de envelhecimento acelerado durante 1000 h com ciclos de 8 h de radia??o UVA a 60 ?C e de 4 h de condensa??o a 50 ?C, para avaliar o comportamento deste material frente ao intemperismo. Ap?s, as amostras de PE puro (PE0) e com aditivo, foram retiradas a cada 200 h e caracterizadas, a fim de identificar as altera??es nas propriedades qu?micas, f?sicas, mec?nicas, t?rmicas e morfol?gicas, causadas pelo efeito do aditivo bem como pelo efeito do intemperismo. Os resultados deste estudo mostraram que o envelhecimento provoca altera??es nas caracter?sticas estruturais (inser??o de grupos funcionais) e nas propriedades morfol?gicas (aparecimento de microfissuras e aumento da rugosidade), mec?nicas (aumento da rigidez e perda de plasticidade) e t?rmicas (aumento da cristalinidade e do intervalo de degrada??o t?rmica), sendo estas altera??es muito atraentes para os microrganismos quando os materiais expostos s?o colocados em contato com o solo. A presen?a do aditivo na matriz de PE ajudou no processo de envelhecimento, uma vez que foram adicionados grupos funcionais na estrutura qu?mica do PEBD. Os Teores de C, N, H e os ?ndices de carbonila das amostras estavam de acordo com os espectros de FTIR. A raz?o C/N de PE8 e PE8/env apresentou o comportamento esperado na literatura (redu??o deste valor) para ocorr?ncia do processo de decomposi??o.
17

Análise da deposição em aplicações aéreas de defensivos em função de diferentes alturas de vôo e volumes de calda /

Salvador, Jonas Felipe, 1984- January 2011 (has links)
Orientador: Ulisses Rocha Antuniassi / Banca: Carolina Aparecida de Souza Queiroz / Banca: Paulo Roberto Arbex Silva / Resumo: O setor florestal brasileiro ocupa destaque no cenário mundial da cultura de florestas plantadas. A ampliação das áreas com florestas plantadas demandam desenvolvimento tecnológico e otimização de mão-de-obra. O uso da aviação está em franca expansão na atividade florestal. O presente trabalho teve o objetivo de definir qual a melhor combinação entre alturas de vôo e volumes de calda na aplicação aérea de herbicidas em área de implantação florestal por meio de análise de deposição das caldas. O experimento foi realizado em área de pastagem da Fazenda Morro Branco, situada no município de Porto Espiridião no Estado de Mato Grosso. O ensaio foi instalado com nove tratamentos que consistiram nas combinações de três volumes de calda (20, 30 e 50 L ha-1) e três alturas de vôo (10, 30 e 40 m). As aplicações foram realizadas utilizando-se uma Aeronave Air Tractor AT-802, equipada com barras contendo 54 bicos com pontas de jato plano ajustáveis. Os dados foram analisados inicialmente por meio de mapas para verificar a variabilidade espacial e tendência da distribuição pontual dos depósitos das caldas. Posteriormente foi realizada a análise comparativa dos tratamentos utilizando o método estatístico "Intervalo de Confiança para Diferenças entre as Médias" com grau de confiança de 95% (IC95%). Para a determinação dos depósitos de calda foi utilizado metodologia de cromatografia líquida de alta eficiência (HPLC) e para determinação de deriva foi utilizado balanço de massas. Em geral, houve tendência de aumento de depósitos de calda com a redução da altura de vôo, independente do volume aplicado. Os tratamentos com altura de vôo de 10 m apresentaram quantidades de depósitos superiores aos demais tratamentos, independente do volume de calda aplicado / Abstract: The Brazilian forestry sector takes a highlight position on the global forest plantations. Forestry plantation areas are in expansion and require technological development and workmanship optimization. The use of aviation technology is growing in forest areas. The aim of the study was to define the best combination of height flight and spray volume rates in aerial herbicides application in forestry establishment area by deposition analysis. The experiment was conducted in a pasture area at Morro Branco Farm, located in Porto Espiridiao City, Mato Grosso State. The test was set up with nine treatments, consisted of three spray volumes rates (20, 30 and 50 L ha-1) and three height flights (10, 30 and 40 m). The applications were performed by Aircraft Air Tractor AT-802, equipped with boom containing 54 nozzles with adjustable flat fan tips. Data were analyzed initially by using maps to determine the spatial distribution and trend of timely deposits of mixtures. Afterwards, for comparison between treatments, the statistical method "Confidence Intervals for Differences between Means" was used, with confidence level of 95%. Spray deposits was determinate by High Performance Liquid Chromatography (HPLC) and for drift determination was used mass balance. In general, there was a tendency to increase spray deposits by reducing flying height, regardless of the volume applied. The treatments with 10 m flying height had higher deposits amounts, regardless of spray volume rate / Mestre
18

Microstructure autour de l'ion Tm observée par corrélation angulaire perturbée

Haroutunian, Roger 20 April 1972 (has links) (PDF)
voir fichier pdf
19

At what age can children reliably and validly self-report their health-related quality of life? An investigation using the PedsQL(tm) 4.0 Generic Core Scales Database

Limbers, Christine A. 15 May 2009 (has links)
Health-related quality of life (HRQOL) assessment has emerged as a vital health outcome measure in clinical trials, healthcare services and evaluation, and population health outcomes research. Reliability, validity, and parent-child agreement of the PedsQL™ 4.0 Generic Core Scales were examined using child self-report and parent proxy-report age subgroup data on over 8,000 children ages 5-16 years from the PedsQL 4.0 Generic Core Scales DatabaseSM. The PedsQL™ 4.0 Generic Core Scales demonstrated good internal consistency reliability for children as young as 5 years; healthy children across the age subgroups demonstrated a statistically significant difference in HRQOL (better HRQOL) than children with a known chronic health condition. Confirmatory factor analysis demonstrated that a 5-factor model fit almost identically across the age subgroups, providing further evidence that children as young as 5 years are reliable and valid self-reporters of their HRQOL. Parent-child agreement was in the moderate-to-good range, with parents reporting significantly higher PedsQL™ 4.0 scores across the age subgroups. In conclusion, the analyses support the reliability and validity of child self-report in children as young as 5 years old.
20

Study on Enzyme and Nucleic Acid Interactions by AFM in Liquids

Hu, Ya-hui 25 July 2006 (has links)
The image resolution of atomic force microscopy (AFM) is still less superior to that of the electron microscopy (EM). However AFM operated in liquids complemented by Tapping-mode (TM) detection proves to be more suitable for imaging biomolecules in physiological-like environments. Nevertheless, manipulation of AFM in solution turned out to be non-trivial, several technical difficulties were encountered. In the thesis, I report using divalent cation-containing buffer as a feasible method to immobilize DNA molecules effectively for imaging in liquid media. AFM operating conditions, such as cantilever oscillating drive frequency, setpoint amplitude, feedback control parameters and scan rates were studied to obtain the optimized function. Various AFM images of Ssp I-linearized pUC19 DNA/EcoR I restriction enzyme complexes were captured, revealing the molecular details of their complex machineries. For example, the intermediate stage of the enzyme cleavage action was displayed by images showing that DNA was bent by an acute angle at the active site in the presence of one single EcoR I molecule. Some evidence for a jumping, sliding or intersegmental transfer mechanism is achieved. To trace the enzyme-DNA interaction dynamic in real time, preliminary results were obtained, but further improvements are required.

Page generated in 0.0292 seconds