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1

Berveglieri, Adilson [UNESP]. "Classificação fuzzy de vertentes por krigagem e TPS com agregação de regiões via diagrama de Voronoi." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/88156.

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Made available in DSpace on 2014-06-11T19:23:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-16Bitstream added on 2014-06-13T20:30:02Z : No. of bitstreams: 1 berveglieri_a_me_prud.pdf: 2017717 bytes, checksum: 69925cc487658d0455ded0ccb94753b8 (MD5)<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>As vertentes, como superf cies inclinadas, consistem em express~oes da Geomorfologia moldadas por fatores naturais (end ogenos e ex ogenos) e pelo pr oprio homem. Suas formas determinam o uxo ou o ac umulo de agua e representam caracter sticas fundamentais para a preven c~ao e resolu c~ao de problemas associados ao relevo, tais como utiliza c~ao do solo, constru c~ao civil entre outros. A classi ca c~ao da vertente em c oncava, convexa ou retil - nea permite a identi ca c~ao de areas conforme sua declividade. Assim, por meio de uma grade retangular regular, base do modelo digital de terreno, gera-se uma malha interpolada por fun c~oes estimadoras: thin-plate spline, que possui caracter sticas de suaviza c~ao e krigagem, que al em da suavidade tamb em considera a depend encia espacial. Logo ap os, a classi ca c~ao e feita, obedecendo a infer encia fuzzy baseada em fun c~oes de pertin encia que de nem classes a partir do c alculo da inclina c~ao e da concavidade ou convexidade do terreno. Entretanto, o resultado dessa classi ca c~ao est a atrelado a resolu c~ao da malha, n~ao permitindo fazer qualquer corre c~ao pontual. Pois, pequenas areas de pouca signi c ancia podem ser formadas, necessitando elimin a-las. Nesse sentido, para que o resultado seja ajustado, aplica-se o diagrama de Voronoi, caracterizado por sua rela c~ao de abrang encia e proximidade, como ferramenta para agregar regi~oes anteriormente classi cadas de modo a permitir um ajuste local e tornar o resultado mais condizente com a area em estudo, quando comparada a mapas geomorfol ogicos correspondentes<br>Slopes, such as inclined surfaces, consist in geomorphological expressions shaped by natural factors (endogenous and exogenous) and also by man himself. Their shapes determine the ow or accumulation of water and represent fundamental characteristics for the prevention and resolution of problems associated with relief, as land use, buildings, and others. Classi- cating slopes in concave, convex or straight allows to identi cate areas based on declivity. Thus, by regular rectangular grid which represents a digital terrain model, it generates a interpolated mesh by estimator functions: thin-plate spline, which has characteristics of smoothing, and kriging, which besides smoothing also considers spatial dependence. After that, the classi cation is realized according to fuzzy inference based on membership functions that de ne classes from the calculation of the slope and concavity or convexity of the ground. However, the classi cation depends on mesh resolution and it not allows any point correction. Once small areas with little importance can be formed requiring eliminate them. In order to adjust the result, it applies the Voronoi diagram, characterized by its comprisement and close relationship and scope, as a tool to aggregate regions previously classi ed and allow a local adjustment, that can provides a consistent result in study areas, if it was compared to the corresponding geomorphological maps
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2

Diogo, Alexandrino José Basto. "Fenomenologia estrutural da dupla curvatura no processo de ideação arquitetónica." Doctoral thesis, Universidade de Lisboa, Faculdade de Arquitetura, 2019. http://hdl.handle.net/10400.5/18528.

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Tese de Doutoramento em Arquitetura, com a especialização em Teoria e Prática do Projeto apresentada na Faculdade de Arquitetura da Universidade de Lisboa para obtenção do grau de Doutor.<br>O elevado valor plástico e a eficiência estrutural intrínseca das formas curvas contrasta paradoxalmente com a sua parca utilização na arquitetura, não tirando proveito das suas potencialidades e tornando-a mais pobre espacialmente. A maior complexidade destas formas, exige por sua vez um maior domínio da geometria, da fenomenologia estrutural e dos processos construtivos, impondo uma visão holística e interdisciplinar, que resulte num processo dialético entre a conceção e a construção. As ferramentas digitais deviam constituir um quadro tecnológico capaz de acolher e responder a estas questões, designadamente da produção das superfícies curvas. Esta realidade emergente exige um processo cognitivo e metodológico, que importa refletir, quer na prática profissional, quer no ensino da arquitetura. As teorias de projeto digital e os seus esquemas taxonómicos, estão longe de refletir as necessidades operativas e teóricas da prática de projeto. Embora intua a sua importância na prática do arquiteto, a sua abordagem é ainda de grande abstração, a um nível semiótico. O trabalho ora produzido recorre a um conjunto de axiomas e teoremas operativos para constituir uma metodologia de carácter funcional, que tem a criatividade como capacidade operativa máxima. A tecnologia construtiva que emerge do pós-guerra regida pela necessidade de baixo custo e rapidez, resulta em sistemas construtivos lineares, inábeis em lidar com a conceção e manuseamento da geometria curva e com a personalização. Esta lacuna foi o pretexto para o desenvolvimento do sistema construtivo Brick-Warp. O sistema referido recorre a peças produzidas em série, personalizadas à posteriori por processos de fabricação digital, juntando a produção em série com a personalização em série. A isto acresce um processo de montagem que recorre ao pré-esforço para estabilizar as peças, dispensando a utilização de cibramento. O que torna o sistema construtivo, pensamos, especialmente competitivo. O trabalho desenvolvido consegue abarcar na sua aproximação ao problema, tanto a a dimensão teórica como a dimensão construtiva, originalidade essa que, pensamos, fortalece a proficiência das proposições apresentadas. Palavras-Chave: Superfícies curvas e dupla curvatura, Fenomenologia estrutural, Sistemas construtivos, Ferramentas digitais, Alvenaria estrutural.<br>ABSTRACT: The inherent structural efficiency of curved shapes and the eminent value of their plasticity contrasts paradoxically with its sparse use in Architecture. This situation prevents the whole subject matter of profiting from this area of great potential, thus rendering it less rich in terms of spacial analysis and use. The greater complexity of these shapes demands in turn a greater mastery of Geometry, structural phenomenology and correspective building processes, imposes a holistic and therefore interdisciplinary approach which results both in and from a dialectal process between conception and construction. The digital tools should make up a technological framework capable of responding to these questions, namely of the creation of curved shapes. The reality demands a cognitive methodology which reflect this, wether in architectural pratice or teaching. Theories for digital processing and their taxonomic schemes are far from reflecting the operational and theoretical demands regarding of project practice. Although it is important in the architect's practice, his approach is still of great abstraction. The present dissertation resorts to a set of principles and theorems to build a functional methodology which holds creativity as its top operating capability. Constructive technology emerging from the post war era, governed by the need for low cost and speed derived into linear constructive systems, inapt to dealing with the design and handling curved geometry or customizing and personalization. This gap was the pretext for the development of the Brick-Warp system. The given system resorted to parts which were mass produced and later personalised by digital fabrication, marrying mass production to mass personalisation. An assembly procedure is then used resorting to pre-stress in order to stabilize the parts thus dismissing the need to apply scaffold. It is these features that will ultimately make the system, we think, specially competitive. The work now completed, encompasses both the theoretical and the constructive dimensions of the problem, the originality of which, we think, strengthens the proficiency of the propsitions now presented.<br>N/A
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3

Arantes, Renata Antônia Tadeu. "Análise e classificação de formas biológicas." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-27112014-114454/.

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Este trabalho representa um estudo pertencente a área de visão computacional, mais especificamente a morfologia biológica e evolução. A análise de formas é fundamental para a solução de muitos problemas relacionados a visão, cujas técnicas de visão computacional podem ser aplicadas em estudos sobre evolução relacionados a biologia. Neste trabalho prestamos uma atenção especial a complexidade do método de análise de formas, introduzindo uma nova e simples característica (a curvatura digital) para ser representadas por marcos anatômicos (\"landmarks\"). É importante observar que este tipo de representação é amplamente aplicado em problemas relacionados à área de morfologia biológica. O trabalho também está direcionado a extração e seleção de características (features) mais informativas obtidas de dados de landmarks, analisando vantagens e desvantagens de sua aplicação. As melhores features morfológicas extraídas serão usadas como ferramentas para classificar as amostras de roedores Thrichomys apereoides da familia Echimydae e obter esquemas hierárquicos (taxonomias) das espécimes e comparar com taxonomias tradicionais. A distribuição geográfica das amostras é também levada em consideração e é observado que existe um bom acordo entre tal distribuição e os grupos obtidos pela análise discriminante considerando as propriedades morfológicas das amostras. Os principais resultados deste trabalho é que a verificação ao menos para os tipos de dados e problemas considerados, um simples método como a curvatura digital pode conduzir para melhores resultados do que aqueles obtidos pelos tradicionais<br>This work addresses the application of computational vision to the area of biological morphology and evolution. Shape analysis plays an important role in the solution of many related problems. In this work we pay special attention to the complexity of shape analysis methods, introducing a new and simple feature (the digital curvature) to be estimated from anatomical landmarks. It is important to observe that this type of representation is widely applied in related problems in biological morphology. The current work also addresses the extraction and selection of the most informative features obtained from landmark data, analyzing the advantages and disadvantages of each approach. The best morphological features extracted are used to classify the samples (Thrichomys apereoides rodents from the Echimydae family) in order to get hierarchical structures (taxonomy) of the species, which is compared to the traditional taxonomy. The geographical distribution of the samples is also taken into account and it is observed that there is a good agreement between such a distribution and the groups obtained by discriminant analysis considering the morphological properties of the samples. The main results of this work is the verification that, at least for the considered type of data and problem, a simple method such as the digital curvature can lead to better results than those obtained by the traditional, more complex, approaches
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4

Koenigkan, Luciano Vieira. "Método de análise do contorno de aglomerados de gotas de chuva artificial em imagem digital." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/18/18133/tde-21032006-181214/.

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Este trabalho apresenta um método para análise do contorno de gotas de chuva artificial em imagem digital, o qual se caracteriza como uma ferramenta para melhor compreensão dos processos agrícolas que envolvem o uso de chuvas artificiais, como a irrigação e a aplicação de defensivos, sendo desenvolvido com o uso de técnicas para análise de formas bidimensionais e processamento de sinais, como representação de formas por contornos paramétricos, análise de Fourier e filtragem gaussiana. Os resultados obtidos demonstram precisão na análise de imagens de aglomerados de gotas, acrescentando as características de descritor apresentadas pela curvatura, assim como a flexibilidade de calibração oferecidas pela abordagem multi-escala adotada, possibilitando a obtenção de erros de medida não maiores que 5%, para os padrões circulares testados com raios entre 10 e 200 pixels<br>This work presents a method for contour analysis of artificial rain drop based on both digital image and curvature processing. The method is characterized as a tool, which allows a better understanding of the raindrops in irrigation and agrochemicals spraying processes. Its development was based on parametric contours representation of shapes, Fourier analysis, and Gaussian filtering. Results show the suitability of the method, which presents errors smaller than 5% for curvature determination in the range of the radius variation in betwen 10 and 200 pixels as well as the ability for raindrop clusters analysis
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5

Lordão, Fernando Augusto Ferreira. "Reconhecimento de formas utilizando modelos de compressão de dados e espaços de escalas de curvatura." Universidade Federal da Paraí­ba, 2009. http://tede.biblioteca.ufpb.br:8080/handle/tede/6137.

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Made available in DSpace on 2015-05-14T12:36:54Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2499209 bytes, checksum: 80d399f8f00f3e82d2a3b34e52fd6b05 (MD5) Previous issue date: 2009-08-27<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>As the processing power of computers increases, the quantity and complexity of stored data have growing in the same way, requiring more sophisticated mechanisms to accomplish retrieval with efficacy and efficiency over these information. In image processing, it has become common the retrieval based on its own content, namely Content-Based Image Retrieval (CBIR), which eliminates the need to place additional annotations as textual descriptions and keywords registered by an observer. The purpose of this work is the development of an image retrieval mechanism based on shape recognition. The mechanism consists in (1) compute the Full Curvature Scale Space (FullCSS) image descriptors; and (2) apply over them a lossless compression method objecting to (3) classify these descriptors and retrieve the corresponding images. The FullCSS descriptors register the curvature variations on the image contour indicating the degree and the signal of these variations, which allow identifying where the curvature is concave or convex. The adopted compression method uses the Prediction by Partial Matching (PPM) compression model, which has been successfully used in other works to classify texture images. The results obtained show that this novel approach is able to reach competitive levels of efficacy and efficiency when compared to other works recently developed in this same area.<br>Com o aumento do poder de processamento dos computadores, cresceu também a quantidade e complexidade dos dados armazenados, exigindo mecanismos cada vez mais sofisticados para se conseguir uma recuperação eficaz e eficiente destas informações. No caso do processamento de imagens, tem se tornado comum a recuperação baseada em seu próprio conteúdo, ou seja, Recuperação de Imagem Baseada em Conteúdo (Content-Based Image Retrieval CBIR), eliminando a necessidade de anotações adicionais como descrições textuais e palavras-chave registradas por um observador. A proposta deste trabalho é o desenvolvimento de um mecanismo de recuperação de imagens através do reconhecimento de sua forma. O mecanismo consiste em (1) calcular os descritores Full Curvature Scale Space (FullCSS) das imagens; e (2) aplicar sobre eles um método de compressão sem perdas com a finalidade de (3) classificar esses descritores e recuperar as imagens correspondentes. Os descritores FullCSS registram as variações na curvatura do contorno da imagem indicando o grau e o sinal dessas variações, permitindo identificar onde a curvatura é côncava ou convexa. O método de compressão adotado utiliza o modelo de compressão Prediction by Partial Matching (PPM), utilizado com sucesso em outros trabalhos para classificar imagens de texturas. Os resultados obtidos indicam que esta abordagem inovadora é capaz de atingir níveis competitivos de eficácia e eficiência quando comparada a outros trabalhos atualmente desenvolvidos nesta mesma área.
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Seguel, Plaza Francisco Javier. "Identificación de daño en placas tipo sándwich usando un sistema de correlación de imágenes digital y la curvatura de los modos de vibración." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/143668.

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Magíster en Ciencias de la Ingeniería, Mención Mecánica<br>Medir la vibración con cámaras de alta velocidad permite la disponibilidad de una gran cantidad de datos, ya que el sistema discretiza la super ficie a medir en un arreglo rectangular de miles de puntos. Contar con datos en alta resolución puede ser un factor positivo a la hora de localizar el daño y determinar su severidad, en especial cuando las zonas afectadas son de poco tamaño. El objetivo de esta investigación es explorar el potencial en el uso de un sistema de correlación de imágenes de alta velocidad (DIC) para la medición de la vibración y la detección de daño por delaminación en placas compuestas tipo panal de abeja. El estudio contempló la preparación de cinco escenarios de daño por delaminación, de diferentes formas y tamaños, más una placa sin daño, y la implementación de tres métodos de detección de daño basados en la curvatura de los modos de vibración: two dimensional gapped smooth method (TDGSM), uniform load surface method (ULSM) y strain energy method (SEM). Se midió la vibración de las placas con un sistema DIC de alta velocidad, en rangos cercanos a sus frecuencias naturales. Con los datos obtenidos mediante el sistema DIC se pudieron obtener los modos de vibrar de las placas, para los distintos escenarios de daño, pudiendo contar con al menos seis modos de vibración por placa. Estos datos fueron tratados con un algoritmo de suavizamiento y recuperación de datos. Posterior a esto, se aplicaron las metodologías de detección, utilizando la información de las placas con y sin daño. Se obtuvieron grá ficos de contorno de los índices de daño obtenidos con los métodos de detección, los cuales proporcionaron imágenes similares a radiografías de las placas. Los resultados obtenidos probaron la efi cacia de los métodos de detección de daño al utilizar la información obtenida mediante el sistema DIC. La curvatura de los modos de vibración es una característica altamente sensible a cambios locales en la estructura, y esta propiedad es la base de todos los métodos de detección utilizados. . Todos los métodos fueron capaces de detectar tanto la localización como parte de la severidad de los escenarios de daño estudiados. En los casos de daño múltiple, en su mayoría, las metodologías solo pudieron detectar uno de los daños presentes en la estructura. Destacó el método SEM , el cual fue capaz de detectar un área delaminada pequeña y un escenario de daño múltiple, que no habían sido detectados en trabajos anteriores, con otras técnicas de detección.<br>Este trabajo ha sido parcialmente financiado por CONICYT
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Suen, Tsz-yin Simon. "Curvature domain stitching of digital photographs." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38800901.

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Suen, Tsz-yin Simon, and 孫子彥. "Curvature domain stitching of digital photographs." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38800901.

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Deshmukh, Prutha. "Damage Detection Of a Cantilever Beam Using Digital Image Correlation." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1623169831665585.

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Nagler, Johannes [Verfasser], Brigitte [Akademischer Betreuer] Forster-Heinlein, Uwe [Akademischer Betreuer] Kähler, and Martin [Akademischer Betreuer] Buhmann. "Digital Curvature Estimation: An Operator Theoretic Approach / Johannes Nagler. Betreuer: Brigitte Forster-Heinlein ; Uwe Kähler ; Martin Buhmann." Passau : Universität Passau, 2015. http://d-nb.info/1078405816/34.

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Felhoelter, Dennis G. "A graphics facility for integration, editing, and display of slope, curvature, and contours from a digital terrain elevation database." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23247.

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12

Gotardo, Paulo Fabiano Urnau. "Segmentaçao de imagens de profundidade utilizando curvaturas de superfícies e um método de estimativa robusto." reponame:Repositório Institucional da UFPR, 2011. http://hdl.handle.net/1884/25439.

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Neste trabalho são apresentadas contribuições para o aperfeiçoamento da segmentação de imagens de profundidade, um processo de fundamental importância a sistemas de visão computacional e ainda um dos maiores desafios nesta área de pesquisa. O principal objetivo é desenvolver técnicas de segmentação que preservem melhor a topologia dos objetos em cena, de modo a auxiliar processos posteriores de representação, modelagem, reconhecimento e reconstrução de objetos, ajudando a diminuir algumas limitações na utilização de sistemas de visão computacional. O problema da segmentação de imagens de profundidade foi abordado em duas formas diferentes e as principais contribuições apresentadas são: (1) dois métodos de deteção de bordas inéditos baseados em valores das curvaturas de superfície H e K e integrando dados de profundidade e de intensidade luminosa correspondentes à mesma cena: e (2) um novo método de segmentação de imagens de profundidade utilizando um algoritmo genético e um método de estimativa robusto, aperfeiçoados, para a extração de superfícies planas das imagens. Através da utilização de uma mesma base de imagens, os resultados experimentais foram comparados positivamente aos resultados obtidos por outros quatro métodos de segmentação de imagens de profundidade, considerados a principal referência no assunto de acordo com a literatura. Os métodos de deteção de bordas integrando dados de intensidade luminosa preservam melhor as formas e localizações de bordas dos objetos em cena e podem ser utilizados para melhorar os resultados obtidos por outros métodos de segmentação. O método de segmentação por extração de superfícies planas foi avaliado quantitativamente, utilizando um conjunto de métricas relacionadas a segmentações manualmente geradas, e apresentou um melhor desempenho na preservação da topologia dos objetos, principalmente, pelo fato de melhor segmentar regiões pequenas das imagens. As contribuições apresentadas constituem avanços relevantes para o aperfeiçoamento da segmentação de imagens de profundidade e estão sendo utilizadas como suporte a um projeto mais amplo, o SRIC3D, em desenvolvimento pelo grupo de pesquisa IMAGO.
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Berveglieri, Adilson. "Classificação fuzzy de vertentes por krigagem e TPS com agregação de regiões via diagrama de Voronoi /." Presidente Prudente : [s.n.], 2011. http://hdl.handle.net/11449/88156.

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Orientador: Messias Meneguette Júnior<br>Banca: João Fernando Custodio da Silva<br>Banca: Ricardo Luís Barbosa<br>Resumo: As vertentes, como superf cies inclinadas, consistem em express~oes da Geomorfologia moldadas por fatores naturais (end ogenos e ex ogenos) e pelo pr oprio homem. Suas formas determinam o uxo ou o ac umulo de agua e representam caracter sticas fundamentais para a preven c~ao e resolu c~ao de problemas associados ao relevo, tais como utiliza c~ao do solo, constru c~ao civil entre outros. A classi ca c~ao da vertente em c^oncava, convexa ou retil - nea permite a identi ca c~ao de areas conforme sua declividade. Assim, por meio de uma grade retangular regular, base do modelo digital de terreno, gera-se uma malha interpolada por fun c~oes estimadoras: thin-plate spline, que possui caracter sticas de suaviza c~ao e krigagem, que al em da suavidade tamb em considera a depend^encia espacial. Logo ap os, a classi ca c~ao e feita, obedecendo a infer^encia fuzzy baseada em fun c~oes de pertin^encia que de nem classes a partir do c alculo da inclina c~ao e da concavidade ou convexidade do terreno. Entretanto, o resultado dessa classi ca c~ao est a atrelado a resolu c~ao da malha, n~ao permitindo fazer qualquer corre c~ao pontual. Pois, pequenas areas de pouca signi c^ancia podem ser formadas, necessitando elimin a-las. Nesse sentido, para que o resultado seja ajustado, aplica-se o diagrama de Voronoi, caracterizado por sua rela c~ao de abrang^encia e proximidade, como ferramenta para agregar regi~oes anteriormente classi cadas de modo a permitir um ajuste local e tornar o resultado mais condizente com a area em estudo, quando comparada a mapas geomorfol ogicos correspondentes<br>Abstract: Slopes, such as inclined surfaces, consist in geomorphological expressions shaped by natural factors (endogenous and exogenous) and also by man himself. Their shapes determine the ow or accumulation of water and represent fundamental characteristics for the prevention and resolution of problems associated with relief, as land use, buildings, and others. Classi- cating slopes in concave, convex or straight allows to identi cate areas based on declivity. Thus, by regular rectangular grid which represents a digital terrain model, it generates a interpolated mesh by estimator functions: thin-plate spline, which has characteristics of smoothing, and kriging, which besides smoothing also considers spatial dependence. After that, the classi cation is realized according to fuzzy inference based on membership functions that de ne classes from the calculation of the slope and concavity or convexity of the ground. However, the classi cation depends on mesh resolution and it not allows any point correction. Once small areas with little importance can be formed requiring eliminate them. In order to adjust the result, it applies the Voronoi diagram, characterized by its comprisement and close relationship and scope, as a tool to aggregate regions previously classi ed and allow a local adjustment, that can provides a consistent result in study areas, if it was compared to the corresponding geomorphological maps<br>Mestre
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14

Sandy, Alexis Emily. "Environmental and Digital Data Analysis of the National Wetlands Inventory (NWI) Landscape Position Classification System." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33572.

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The National Wetlands Inventory (NWI) is the definitive source for wetland resources in the United States. The NWI production unit in Hadley, MA has begun to upgrade their digital map database, integrating descriptors for assessment of wetland functions. Updating is conducted manually and some automation is needed to increase production and efficiency. This study assigned landscape position descriptor codes to NWI wetland polygons and correlated polygon environmental properties with public domain terrain, soils, hydrology, and vegetation data within the Coastal Plain of Virginia. Environmental properties were applied to a non-metric multidimensional scaling technique to identify similarities within individual landscape positions based on wetland plant indicators, primary and secondary hydrology indicators, and field indicators of hydric soils. Individual NWI landscape position classes were linked to field-validated environmental properties. Measures provided by this analysis indicated that wetland plant occurrence and wetland plant status obtained a stress value of 0.136 (Kruskalâ s stress measure = poor), which is a poor indicator when determining correlation among wetland environmental properties. This is due principally to the highly-variable plant distribution and wetland plant status found among the field-validated sites. Primary and secondary hydrology indicators obtained a stress rating of 0.097 (Kruskalâ s stress measure = good) for correlation. The hydrology indicators measured in this analysis had a high level of correlation with all NWI landscape position classes due the common occurrence of at least one primary hydrology indicator in all field validated wetlands. The secondary indicators had an increased accuracy in landscape position discrimination over the primary indicators because they were less ubiquitous. Hydric soil characteristics listed in the 1987 Manual and NTCHS field indicators of hydric soils proved to be a relatively poor indicator, based on Kruskalâ s stress measure of 0.117, for contrasting landscape position classes because the same values occurred across all classes. The six NWI fieldâ validated landscape position classes used in this study were then further applied in a public domain digital data analysis. Mean pixel attribute values extracted from the 180 field-validated wetlands were analyzed using cluster analysis. The percent hydric soil component displayed the greatest variance when compared to elevation and slope curvature, streamflow and waterbody, Cowardin classification, and wetland vegetation type. Limitations of the soil survey data included: variable date of acquisition, small scale compared to wetland size, and variable quality. Flow had limitations related to its linear attributes, therefore is often found insignificant when evaluating pixel values that are mean of selected pixels across of wetland landscape position polygons. NLCD data limitations included poor quality resolution (large pixel size) and variable classification of cover types. The three sources of information that would improve wetland mapping and modeling the subtle changes in elevation and slope curvature that characterize wetland landscapes are: recent high resolution leaf-off aerial photography, high-quality soil survey data, and high-resolution elevation data. Due to the data limitations and the choice of variables used in this study, development of models and rules that clearly separate the six different landscape positions was not possible, and thus automation of coding could not be attempted.<br>Master of Science
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15

Burgholzer, Robert William. "Using Accumulation Based Network Identification Methods to Identify Hill Slope Scale Drainage Networks in a Raster GIS." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/32001.

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The simple accumulation-based network identification method (ANIM) in a raster Geographic Information System (GIS) posed by Oâ Callaghan and Mark (1984) has been criticized for producing a spatially uniform drainage density (Tarboton 2002) at the watershed scale. This criticism casts doubt on the use of ANIMs for deriving properties such as overland flow length for nonpoint source pollution models, without calibrating the accumulation threshold value. However, the basic assumption that underlies ANIMs is that convergent topography will yield a more rapid accumulation of cells, and thus, more extensive flow networks, with divergent, or planar terrain yielding sparser networks. Previous studies have focused on networks that are coarser than the hill-slope scale, and have relied upon visual inspection of drainage networks to suggest that ANIMs lack the ability to produce diverse networks. In this study overland flow lengths were calculated on a sub-watershed basis, with standard deviation, and range calculated for sub-watershed populations as a means of quantifying the diversity of overland flow lengths produced by ANIM at the hill slope scale. Linear regression and Spearman ranking analyses were used to determine if the methods represented trends in overland flow length as suggested by manual delineation of contour lines. Three ANIMs were analyzed: the flow accumulation method (Oâ Callaghan and Mark, 1984), the terrain curvature method (Tarboton, 2000) and the ridge accumulation method (introduced in this study). All three methods were shown to produce non-zero standard deviations and ranges using a single support area threshold, with the terrain curvature method producing the most diverse networks, followed by the ridge accumulation method, and then the flow accumulation method. At an analysis unit size of 20 ha, the terrain curvature method produced a standard deviation that was most similar to those suggested by the contour crenulations, -13.5%, followed by the ridge accumulation method, -21.5%, and the flow accumulation method, -61.6%. The ridge accumulation produced the most similar range, -19.1%, followed by terrain curvature, -24.9%, and flow accumulation, -65.4%. While the flow accumulation networks had a much narrower range of predicted flow lengths, it had the highest Spearman ranking coefficient, Rs=0.722, and linear regression coefficient, R2=0.602. The terrain curvature method was second, Rs=0.641, R2=0.469, and then ridge accumulation, Rs=0.602, R2=0.490. For all methods, as threshold values were varied, areas of dissimilar morphology (as evidenced by the common stream metric stream frequency) experienced changes in overland flow lengths at different rates. This results in an inconsistency in ranking of sub-watersheds at different thresholds. When thresholds were varied to produce average overland flow lengths from 75 m to 150 m, the terrain curvature method showed the lowest incidence of rank change, 16.05%, followed by the ridge accumulation method, 16.73%, then flow accumulation, 25.18%. The results of this investigation suggest that for all three methods, a causal relationship exists between threshold area, underlying morphology, and predicted overland flow length. This causal relationship enables ANIMs to represent contour network trends in overland flow length with a single threshold value, but also results in the introduction of rank change error as threshold values are varied. Calibration of threshold value (varying threshold in order to better match observed overland flow lengths) is an effective means of increasing the accuracy of ANIM predictions, and may be necessary when comparing areas with different stream frequencies. It was shown that the flow accumulation method produces less diverse networks than the terrain curvature and ridge accumulation methods. However, the results of rank and regression analyses suggest that further investigation is required to determine if these more diverse ANIM are in fact more accurate than the flow accumulation method.<br>Master of Science
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16

Hill, Evelyn June. "Applying statistical and syntactic pattern recognition techniques to the detection of fish in digital images." University of Western Australia. School of Mathematics and Statistics, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0070.

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This study is an attempt to simulate aspects of human visual perception by automating the detection of specific types of objects in digital images. The success of the methods attempted here was measured by how well results of experiments corresponded to what a typical human’s assessment of the data might be. The subject of the study was images of live fish taken underwater by digital video or digital still cameras. It is desirable to be able to automate the processing of such data for efficient stock assessment for fisheries management. In this study some well known statistical pattern classification techniques were tested and new syntactical/ structural pattern recognition techniques were developed. For testing of statistical pattern classification, the pixels belonging to fish were separated from the background pixels and the EM algorithm for Gaussian mixture models was used to locate clusters of pixels. The means and the covariance matrices for the components of the model were used to indicate the location, size and shape of the clusters. Because the number of components in the mixture is unknown, the EM algorithm has to be run a number of times with different numbers of components and then the best model chosen using a model selection criterion. The AIC (Akaike Information Criterion) and the MDL (Minimum Description Length) were tested.The MDL was found to estimate the numbers of clusters of pixels more accurately than the AIC, which tended to overestimate cluster numbers. In order to reduce problems caused by initialisation of the EM algorithm (i.e. starting positions of mixtures and number of mixtures), the Dynamic Cluster Finding algorithm (DCF) was developed (based on the Dog-Rabbit strategy). This algorithm can produce an estimate of the locations and numbers of clusters of pixels. The Dog-Rabbit strategy is based on early studies of learning behaviour in neurons. The main difference between Dog-Rabbit and DCF is that DCF is based on a toroidal topology which removes the tendency of cluster locators to migrate to the centre of mass of the data set and miss clusters near the edges of the image. In the second approach to the problem, data was extracted from the image using an edge detector. The edges from a reference object were compared with the edges from a new image to determine if the object occurred in the new image. In order to compare edges, the edge pixels were first assembled into curves using an UpWrite procedure; then the curves were smoothed by fitting parametric cubic polynomials. Finally the curves were converted to arrays of numbers which represented the signed curvature of the curves at regular intervals. Sets of curves from different images can be compared by comparing the arrays of signed curvature values, as well as the relative orientations and locations of the curves. Discrepancy values were calculated to indicate how well curves and sets of curves matched the reference object. The total length of all matched curves was used to indicate what fraction of the reference object was found in the new image. The curve matching procedure gave results which corresponded well with what a human being being might observe.
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17

Hu, Min. "Local variation in bending stiffness in structural timber of Norway spruce : for the purpose of strength grading." Licentiate thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-38119.

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Most strength grading machines on the European market use an averagemodulus of elasticity (MOE), estimated on a relatively large distance along awood member, as the indicating property (IP) to bending strength. Theaccuracy of such grading machines in terms of coefficient of determination israther low at R2 ≈ 0.5. This research is motivated by a desire to increase theaccuracy of the strength grading in the industry today. The aim of the presentstudy is to contribute knowledge of local variation in bending stiffness/MOEwith high resolution and thus locate weak sections due to stiffness reducingfeatures (the most important is knots) for structural timber.The present study introduces three methods that involve structural dynamics,classical beam theory and optical measurement to assess local wood stiffness.Specifically: The dynamic method, in which a wood member is treated as an ordinaryphysical structure and the local stiffness is studied by exploring itsdynamic properties. In Method II, a bending MOE profile is established based on local fibre angle information. The local fibre orientation is detected through highresolution laser scanning based on the tracheid effect.  For Method III, a bending MOE profile is established using surfacestrain information under four-point bending. A high resolution strainfield is obtained using the digital image correlation (DIC) technique. From the present study, the two latter methods are more favourable inevaluating the local stiffness within a piece of structural timber. Moreover, thestudy reveals that the established bending MOE profiles using the two lattermethods, i.e. based on information of the local fibre angle and surface strain,agree reasonably well. However, for some patterns of knot clusters, the localbending MOE, calculated on the basis of fibre angles, is significantly higherthan the local bending MOE estimated on the basis of surface strain.<br>De flesta av de utrustningar för hållfasthetssortering som utnyttjas på deneuropeiska marknaden använder ett medelvärde på elasticitetsmodulen(MOE), beräknat på en relativt stor längd av en sågad planka, som indikativparameter (IP). Sådan hållfasthetssortering ger en noggrannhet i termer avförklaringsgrad på R2 ≈ 0.5, vilket är ganska lågt. Arbetet i denna studiemotiveras av en önskan att öka noggrannheten i hållfasthetssorteringen. Syftetmed denna studie är att bidra med kunskap om lokala variationer iböjstyvhet/MOE med hög upplösning och att lokalisera veka snitt (där kvistarär den viktigaste försvagande faktorn) för konstruktionsvirke.Den aktuella studien introducerar tre metoder som omfattar strukturdynamik,klassisk balkteori och optisk mätning vid bedömningen av lokal styvhet imaterialet. Specifikt:  Metod I, där den lokala böjstyvheten studerades genom de dynamiskaegenskaperna såsom egenfrekvens och modform.  Metod II, där en MOE profil beräknas på basis av information om lokalafibervinklar på ett virkesstyckes ytor. Den lokala fiberorienteringen mätsmed högupplöst laserskanning baserad på den så kallade trakeideffekten.  Metod III, där en MOE-profil fastställdes med hjälp avtöjningsinformation för en hel flatsida av en planka belastad med konstantböjmoment. Det högupplösta töjningsfältet erhölls med hjälp av teknikför Digital Image Correlation (DIC). Studien visar att de två sistnämnda metoderna är mycket lämpade för attutvärdera den lokala styvheten i ett virkesstycke. Dessutom visar studien att deMOE-profiler som togs fram med hjälp av de två sistnämnda metoderna,vilka baseras på information om lokala fibervinklar och töjningsfältet på ytan,stämde överens för större delen av virkesstycket. För visa kvistgrupper kan dock den lokala böjstyvheten högre med metoden baserad på fibervinklar.
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18

Li, Yongqiang. "Experimental Studies on the Mechanical Durability of Proton Exchange Membranes." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/29944.

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Three testing methods are proposed to characterize properties of fuel cell materials that affect the mechanical durability of proton exchange membranes (PEMs). The first two methods involved measuring the in-plane biaxial strength of PEMs and the biaxial hygrothermal stresses that occur in PEMs during hygrothermal cycles. The third method investigated the nonuniform thickness and compressibility of gas diffusion media which can lead to concentrated compressive stresses in the PEM in the through-plane direction. Fatigue and creep to leak tests using multi-cell pressure-loaded blister fixtures were conducted to obtain the lifetimes of PEMs before reaching a threshold value of gas leakage. These tests are believed to be more relevant than quasi-static uniaxial tensile to rupture tests because of the introduction of biaxial cyclic and sustained loading and the use of gas leakage as the failure criterion. They also have advantages over relative humidity cycling test because of the controllable mechanical loading. Nafion® NRE-211 membrane was tested at three different temperatures and the time-temperature superposition principle was used to construct a stress-lifetime master curve. Tested at 90oC, extruded Ion Power® N111-IP membrane was found to have longer lifetime than GoreTM-Select® 57 and Nafion NRE-211 membranes under the same blister pressure profiles. Bimaterial specimens fabricated by bonding a piece of PEM to a substrate material were used to measure the hygral stresses, compressive and tensile, in the PEM during relative humidity cycles. The substrate material and its thickness were carefully chosen so that stresses in the PEM could be obtained directly from the curvature of the bimaterial specimen without knowing the constitutive properties of the PEM. Three commercial PEMs were tested at 80oC by cycling the relative humidity between 90% and 0% and by drying the membrane to 0%RH after submersion in liquid water. Stress histories for all three membranes show strong time-dependencies and Nafion® NRE-211 exhibited the largest tensile stress upon drying. Besides in-plane stresses, hard spots in gas diffusion media (GDM) can locally overcompress PEMs in the out-of-plane direction and cause electrical shorting. In this study, GDM samples sealed with an impermeable Kapton® film on the surface were compressed with uniform air pressure and the nonuniform displacement field was measured with a three-dimensional digital image correlation technique. Hard spots as a result of the nonuniform thickness and compressibility of the GDM were found and their severities as stress risers are evident. Locally, a nominal platen compression (similar to bipolar plate land compression) of 0.68 MPa can lead to compressive stress as large as 2.30 MPa in various hard spots that are in the order of 100s µm to 1 mm in size.<br>Ph. D.
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19

Rugis, John. "Digital surface curvature." 2008. http://hdl.handle.net/2292/3105.

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The theoretical basis for this thesis can be found in the subject of differential geometry where both line and surface curvature is a core feature. We begin with a review of curvature basics, establish notational conventions, and contribute new results (on n-cuts) which are of importance for this thesis. A new scale invariant curvature measure is presented. Even though curvature of continuous smooth lines and surfaces is a well-defined property, when working with digital surfaces, curvature can only be estimated. We review the nature of digitized surfaces and present a number of curvature estimators, one of which (the 3-cut mean estimator) is new. We also develop an estimator for our new scale invariant curvature measure, and apply it to digital surfaces. Surface curvature maps are defined and examples are presented. A number of curvature visualization examples are provided. In practical applications, the noise present in digital surfaces usually precludes the possibility of direct curvature calculation. We address this noise problem with solutions including a new 2.5D filter. Combining techniques, we introduce a data processing pipeline designed to generate surface registration markers which can be used to identify correspondences between multiple surfaces. We present a method (projecting curvature maps) in which high resolution detail is merged with a simplified mesh model for visualization purposes. Finally, we present the results of experiments (using texture projection merging and image processing assisted physical measurement) in which we have identified, characterized, and produced visualizations of selected fine surface detail from a digitization of Michelangelo’s David statue.
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20

Goodpasture, Brenda K., and Robert(Robert B. ). McGhee. "Terrain classification from digital elevation data using slope and curvature information." Thesis, 1987. http://hdl.handle.net/10945/22546.

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21

Villa, C., Jo Buckberry, and N. Lynnerup. "Evaluating osteological ageing from digital data." 2016. http://hdl.handle.net/10454/8762.

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Yes<br>Age at death estimation of human skeletal remains is one of the key issues in constructing a biological profile both in forensic and archaeological contexts. The traditional adult osteological methods evaluate macroscopically the morphological changes that occur with increasing age of specific skeletal indicators, such as the cranial sutures, the pubic bone, the auricular surface of the ilium and the sternal end of the ribs. Technologies such as CT and laser scanning are becoming more widely used in anthropology, and several new methods have been developed. This review focuses on how the osteological age-related changes have been evaluated in digital data. Firstly, the 3D virtual copies of the bones have been used to mimic the appearance of the dry bones and the application of the traditional methods. Secondly, the information directly extrapolated from CT scan has been used to qualitatively or quantitatively assess the changes of the trabecular bones, the thickness of the cortical bones, and to perform morphometric analyses. Lastly, the most innovative approach has been the mathematical quantification of the changes of the pelvic joints, calculating the complexity of the surface. The importance of new updated reference datasets, created thanks to the use of CT scanning in forensic settings, is also discussed.<br>CV was supported from the Danish Council for Independent Research (DFF – 4005-00102B – FTP)
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22

Lin, Yi, and 林毅. "On-Chip Curvature Correction Technique Suitable for All-Digital Time-Domain Temperature Sensor." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/xh8mnh.

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YOU, SONG-QUAN, and 尤松泉. "Design and Implementation of High-Accuracy All-Digital Temperature Sensor with Auto Curvature Correction." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f8hmme.

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碩士<br>國立高雄第一科技大學<br>電子工程系碩士班<br>106<br>This paper presents a high-accuracy all-digital smart temperature sensor (STS), including an automatic correction and measurement system, which can more effectively improve STS accuracy and automatically assist the chips measurement to further save test time and cost. Inverter-based STS has the advantages of low cost, low power consumption. The one-point calibration technique that can eliminate the effect for process variation and reduce the testing time and cost. However, the output curve exists for a certain curvature to seriously affect the accuracy. A previously simple curvature correction circuit (CCC) was proposed to correct the curvatures of all sensors by using only one sample sensor. The method is simple and effective, but each sensor still has different curvature, so error will exist. Furthermore, the error curve is not ideally symmetrical to the calibration temperature point, a curvature correction method is proposed in this paper, and more sensors curvature parameters () and linear parameters () can be calculated by automatic curvature correction system. The proposed modified CCC to accurately remove each sensor curve error and linearity error to obtain the best accuracy, the correct technique can be directly suitable for all CMOS processes. The proposed STS was implemented in eight Xilinx Field Programmable Gate Arrays (FPGA) for performance verification. The logic utilization for total circuit is 89 slices, which is increased by 16% compared to the previous with 74 slices. The error in the temperature range from -20 °C to 100 °C is improved from 1.6 ºC to 1.1 ºC, which is equivalent to a precision improvement of more than 30%. This result is effectively proved that the proposed method has its significance. Finally, the automatic correction and measurement system can assist the measurement of chips read and report, can greatly reduce labor costs and time.
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Lin, Shih-Hao, and 林世豪. "Design and Realization of All-Digital Smart Temperature Sensor with Curvature Correction and One-Point Calibration Support." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/91858710946298840589.

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Chung, Che-Yuan, and 張哲源. "Using the CCD digital Camera and Inclinometer to Measure the Curvature and Ovalization of Each Section for Circular under Cyclic Bending." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/3p7x9b.

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碩士<br>國立成功大學<br>工程科學系碩博士班<br>92<br>In this project, an accurate and easy to set up curvature and ovalization for each section measurement apparatus for circular tubes is proposed. The apparatus contains:a CCD digital camera, two inclinometers and a self-designed bracket. The bracket has two extended arms on both sides, the front of each arm has a clamp. The clamp can grab the circular tube tightly, and an inclinometer is under each clamp. The bracket will move up and down along with the cyclic bending when the circular tube is subjected to cyclic bending. The CCD digital camera will take photograph of the change of the circular tube during the bending process. Simultaneously, the two inclinometer under the clamps will detect angle changes of the circular tube during the bending process, Next, the images taken by the CCD digital camera will transfer to a computer, and a image process software will analyze to obtain the ovalization of each section for circular tube under cyclic bending. Simultaneously, the angle changes detected by two inclinometers will transfer to a computer, too, the curvature for circular tube under cyclic bending can be calculated through a very simple calculation process. For testing the capability of this newly designed measurement apparatus, the tube bending will be used to experimentally test the AL-7005 stainless steel tubes with be used to measure the curvature and ovalization of each section for AL-7005 stainless steel tubes under cyclic bending.
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Kufner, Jan. "Vztah morfometrických charakteristik terénu a síťových analýz v prostředí GIS." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-323462.

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The main objective of the diploma thesis is creation of methodology and automatization of calibration process of network graph based on the values of morphometric characteristics and motion vectors. The resulting morphometric values of the terrain have been detected on the basis of mathematical and cartographic methods for line course expression. The most accurate one has been used in GIS network analysis over the road network and digital terrain models, which were chosen as the most appropriate for this purpose. Relationship between morphometric values and values suitable for use in network analysis (speed, time, ...) has been studied using specific examples in appropriately selected territory with using selected vehicle, which was designated as a bicycle. The practical part for the verification of functionality of the suggested methodology has been compared with other models of accessibility, available web-map portals and route planners. The process of transport network evaluation based on selected parameters has been automated in Python programming language as a tool in ArcGIS software, which is attached to the diploma thesis. Powered by TCPDF (www.tcpdf.org)
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(8300103), Shams R. Rahmani. "Digital Soil Mapping of the Purdue Agronomy Center for Research and Education." Thesis, 2020.

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This research work concentrate on developing digital soil maps to support field based plant phenotyping research. We have developed soil organic matter content (OM), cation exchange capacity (CEC), natural soil drainage class, and tile drainage line maps using topographic indices and aerial imagery. Various prediction models (universal kriging, cubist, random forest, C5.0, artificial neural network, and multinomial logistic regression) were used to estimate the soil properties of interest.
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