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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.
1

Utilization of Canopy Reflectance to Predict Yield Response of Corn and Cotton to Varying Nitrogen Rates

Rattanakaew, Totsanat 11 December 2015 (has links)
Fertilizer N is one of the most costly inputs in corn (Zea mays L.) and cotton (Gossypium hirsutum L.) production and is a strong yield determining factor. Variable rate N fertilization has the potential to improve resource use efficiency, profitability, and help to minimize adverse environmental impacts. Vegetation indices (VIs) may be useful for in-season crop health monitoring to assist in fertilizer N management and yield prediction. This research determined the utility of aerial imagery in detecting corn and cotton response to varying N supply using five selected VIs. The VIs derived from aerial images, chlorophyll readings and tissue N for corn from V5 to V9 growth stages and cotton beginning the 1st week of flowering through to latelowering were used to relate to fertilizer N rates and plant N status and yield. The results showed that VIs derived from aerial imagery could be used to differentiate N supply and in-season grain yield of corn beginning at V5 to V6; however, models from later growth stages had greater r2 values than earlier growth stages. Single variable models that used VI, chlorophyll content, or plant N concentration as an independent variable were overall stronger than 2 variable Multiple Linear Regression models (MLRs). Three independent variables used in MLRs contained multicollinearity. For cotton, the use of VIs derived from aerial imagery to differentiate N supply may depend on environmental factors such as soil and weather. However, VIs may be useful for in-season lint yield prediction beginning the 1st week of flowering although later stages improved accuracy. The MLRs that were developed with 2 independent variables may be more suitable for in-season lint yield prediction than single independent variable models.
2

Isually Lossless Coding for Color Aerial Images Using PEG

Oh, Han, Kim, Yookyung 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper describes a psychophysical experiment to measure visibility thresholds (VT) for quantization distortion in JPEG2000 and an associated quantization algorithm for visually lossless coding of color aerial images. The visibility thresholds are obtained from a quantization distortion model based on the statistical characteristics of wavelet coefficients and the deadzone quantizer of JPEG2000, and the resulting visibility thresholds are presented for the luminance component (Y) and two chrominance components (Cb and Cr). Using the thresholds, we have achieved visually lossless coding for 24-bit color aerial images at an average bitrate of 4.17 bits/pixels, which is approximately 30% of the bitrate required for numerically lossless coding.
3

Simulação litográfica / Litographic simulation

Ferla, Tania Mara January 2014 (has links)
Litografia óptica é o processo pelo qual os padrões desenhados pelos projetistas de circuitos integrados são transferidos para o wafer através de ondas de luz. Com a miniaturização dos componentes, aumenta cada vez mais a discrepância entre os padrões projetados e o que é realmente impresso. Tal fato ocorre porque as dimensões dos padrões são menores do que o comprimento de onda utilizado para imprimi-los. Desta forma, é imprescindível que se saiba ou se tenha uma aproximação do que será impresso antes da fabricação dos circuitos para eliminar possíveis defeitos, através da utilização de técnicas de melhoramento de resolução. Essa aproximação é obtida através de simuladores de litografia óptica, que possuem o grande desafio de obter uma aproximação em um tempo viável. Sendo assim, neste trabalho apresentamos o problema de litografia óptica e seu embasamento matemático, bem como técnicas para implementar um simulador litográfico de forma eficiente. Tais técnicas foram utilizadas para o desenvolvimento do simulador Lithux. E, também apresentamos brevemente, técnicas de melhoramento de resolução, onde muitas utilizam simuladores de litografia para reproduzir sua eficiência. / Optical Lithography is the process whereby the patterns designed by the integrated circuit designers are transferred to the wafer by light waves. With the miniaturization of components, the gap between the projected patterns and what is actually printed is steadily increasing as the pattern dimensions are now smaller than the wavelength used to print them. Therefore, in this work we present the problem of optical lithography and its mathematical foundations, as well as techniques to efficiently implement a lithographic simulator. These techniques were used to develop the Lithux simulator. We also briefly present techniques for resolution enhancement, where many of them use lithographic simulators to simulate their efficiency. Thus, it is essential to know or to have an approximation of what will be printed before the circuit manufacturing to eliminate potential defects through the use of resolution enhancement techniques. This approximation is obtained by optical lithography simulators that have the challenge of getting this approximation in a practicable time.
4

The Study of Aerial Images Enhancement by Bi-dimensional Empirical mode Decomposition

Hu , Chun-Ting 20 February 2012 (has links)
Aerial images had been used in various fields. If the shooting it in conditions of bad weather, that quality was damage. So requires use of image processing methods for improvement. With the growth and progress of technology, image enhancement method is quickly flourishing. That needs of different options for the appropriate treatment. In this study, image enhancement by the nature of Bi-dimensional empirical mode decomposition (BEMD). Empirical mode decomposition in nonlinear signal processing has excellent results. It can break out some of the base signal and trend. In the BEMD of the signal information for the edge of the image, the trend term for the light distribution. Decomposition can be retained the edge features of the image, and contrast of light and shadow maps make adjustments to improve the uneven lighting situations. In order to retain the color information, so the decomposition of the image before the image for color conversion, will be divided into three¡@degrees of brightness and color images, and then the brightness of the image for the¡@decomposition of the action. The use of subjective and objective image evaluation indicators, to determine the two-dimensional empirical mode decomposition¡@ method with other image enhancement difference. The results show that the conventional image enhancement has a problem that bright side of the whole image, resulting in reduced edge feature information. However, BEMD to effectively improve the image problem of uneven brightness and thoroughly to keep edge features.
5

Simulação litográfica / Litographic simulation

Ferla, Tania Mara January 2014 (has links)
Litografia óptica é o processo pelo qual os padrões desenhados pelos projetistas de circuitos integrados são transferidos para o wafer através de ondas de luz. Com a miniaturização dos componentes, aumenta cada vez mais a discrepância entre os padrões projetados e o que é realmente impresso. Tal fato ocorre porque as dimensões dos padrões são menores do que o comprimento de onda utilizado para imprimi-los. Desta forma, é imprescindível que se saiba ou se tenha uma aproximação do que será impresso antes da fabricação dos circuitos para eliminar possíveis defeitos, através da utilização de técnicas de melhoramento de resolução. Essa aproximação é obtida através de simuladores de litografia óptica, que possuem o grande desafio de obter uma aproximação em um tempo viável. Sendo assim, neste trabalho apresentamos o problema de litografia óptica e seu embasamento matemático, bem como técnicas para implementar um simulador litográfico de forma eficiente. Tais técnicas foram utilizadas para o desenvolvimento do simulador Lithux. E, também apresentamos brevemente, técnicas de melhoramento de resolução, onde muitas utilizam simuladores de litografia para reproduzir sua eficiência. / Optical Lithography is the process whereby the patterns designed by the integrated circuit designers are transferred to the wafer by light waves. With the miniaturization of components, the gap between the projected patterns and what is actually printed is steadily increasing as the pattern dimensions are now smaller than the wavelength used to print them. Therefore, in this work we present the problem of optical lithography and its mathematical foundations, as well as techniques to efficiently implement a lithographic simulator. These techniques were used to develop the Lithux simulator. We also briefly present techniques for resolution enhancement, where many of them use lithographic simulators to simulate their efficiency. Thus, it is essential to know or to have an approximation of what will be printed before the circuit manufacturing to eliminate potential defects through the use of resolution enhancement techniques. This approximation is obtained by optical lithography simulators that have the challenge of getting this approximation in a practicable time.
6

Simulação litográfica / Litographic simulation

Ferla, Tania Mara January 2014 (has links)
Litografia óptica é o processo pelo qual os padrões desenhados pelos projetistas de circuitos integrados são transferidos para o wafer através de ondas de luz. Com a miniaturização dos componentes, aumenta cada vez mais a discrepância entre os padrões projetados e o que é realmente impresso. Tal fato ocorre porque as dimensões dos padrões são menores do que o comprimento de onda utilizado para imprimi-los. Desta forma, é imprescindível que se saiba ou se tenha uma aproximação do que será impresso antes da fabricação dos circuitos para eliminar possíveis defeitos, através da utilização de técnicas de melhoramento de resolução. Essa aproximação é obtida através de simuladores de litografia óptica, que possuem o grande desafio de obter uma aproximação em um tempo viável. Sendo assim, neste trabalho apresentamos o problema de litografia óptica e seu embasamento matemático, bem como técnicas para implementar um simulador litográfico de forma eficiente. Tais técnicas foram utilizadas para o desenvolvimento do simulador Lithux. E, também apresentamos brevemente, técnicas de melhoramento de resolução, onde muitas utilizam simuladores de litografia para reproduzir sua eficiência. / Optical Lithography is the process whereby the patterns designed by the integrated circuit designers are transferred to the wafer by light waves. With the miniaturization of components, the gap between the projected patterns and what is actually printed is steadily increasing as the pattern dimensions are now smaller than the wavelength used to print them. Therefore, in this work we present the problem of optical lithography and its mathematical foundations, as well as techniques to efficiently implement a lithographic simulator. These techniques were used to develop the Lithux simulator. We also briefly present techniques for resolution enhancement, where many of them use lithographic simulators to simulate their efficiency. Thus, it is essential to know or to have an approximation of what will be printed before the circuit manufacturing to eliminate potential defects through the use of resolution enhancement techniques. This approximation is obtained by optical lithography simulators that have the challenge of getting this approximation in a practicable time.
7

CHARACTERISTICS AND APPLICATIONS OF A SCANNING NANO-SLIT OPTICAL SENSOR

George, Anoop January 2011 (has links)
In this dissertation, imaging characteristics of a nano-slit are investigated. Applications of a scanning and rotating nano-slit in measuring sub-micron aerial features are demonstrated. Coherent sub-micron spot distributions are reconstructed with a very high contrast. Finally, high NA partially coherent images with features as small as 210 nm half-pitch are reconstructed and the ultimate resolution of the system is determined.A nano-slit is characterized as a sensor for coherent line-and-space features. Experiments and simulation verify image detection with contrasts greater than 0.9. Effects of polarization on imaging performance are reported. A scanning and rotating nano-slit in conjunction with a filtered back-projection technique is used to reconstruct sub-micron coherent spot distributions. Simulation results show very good agreement with the experiment. Further, it is shown that the reconstruction is very resilient to some common random experimental errors.Imaging characteristics of a scanning nano-slit sensor are determined for high NA partially coherent images. Good imaging performance (contrast > 0.8) is demonstrated with line-and-space images up to a spatial frequency of 2.38 lp / micron. Sub-micron features in a high NA partially coherent image are measured with a scanning and rotating nano-slit. A modified microscope is used to create the measured features, including 210 nm half-pitch features that cannot be imaged using the microscope in a conventional imaging mode. Using the filtered back projection technique, two-dimensional sub-micron features are reconstructed by the nano-slit sensor. It is determined that the resolution limit of ~ 200 nm is determined by the reconstruction technique and not by the width of the nano-slit.
8

Para onde cresce a cidade: dinâmica de expansão urbana e caracterização urbano-ambiental em área da bacia do Guarapiranga / Urban growing: urban evolution and the Guarapiranga´s Basin urban environmental caracterization

Bielavsky, Mariana 13 June 2006 (has links)
Essa pesquisa trata do crescimento urbano e implicações ambientais de uma área na bacia do Guarapiranga. Essa área abrange parte dos municípios de São Paulo, Itapecerica da Serra e Embu Guaçu. O intuito é apresentar a evolução urbana da área entre os anos 1962 e 2001, com análises de fotografias áreas. Em uma escala intra-urbana, a pesquisa apresenta a interpretação de fotografias áreas para o ano de 2001 criando a carta de áreas homogêneas urbanas. Os principais dados dessa pesquisa são para o ano de 2001, de modo que pudemos os indicadores sócio-demográficos dos dados do censo do IBGE realizado para o ano de 2000.Com todos esses dados, podemos apontar os vetores de crescimento urbano da área, assim como seus problemas sócio-ambientais. / This research is about the urban growing in an area wich is considered model in the Guarapiranga´s Basin. This area encloses the citys of São Paulo, Itapecerica da Serra and Embu Guaçu. The intention is present the urban evolution of the area between the years 1962 and 2001, with analyses of aerial photography. In intra urban scale, the research presents the aerial photography\'s urban interpretation for the year 2001, making the maps of the urban homogenous zones areas. The main data or this research is about the year 2001, in the way that we could have the social demography in the IBGE´s censo data for the year 2000. With all this data, we have got the growing expansion city vectors as also the social and ambient problems.
9

Extração de contornos de telhados de edifícios a partir da integração de imagem aérea de alta-resolução e dados LASER, utilizando campos aleatórios de Markov / Extraction of building roof countors through integration of high-resolution aerial images and LASER data, using Markov random field

Fernandes, Vanessa Jordão Marcato [UNESP] 19 December 2016 (has links)
Submitted by VANESSA JORDÃO MARCATO FERNANDES null (vanessamarcato@yahoo.com.br) on 2017-01-30T18:15:29Z No. of bitstreams: 1 fernandes_vjm_tese.pdf: 25329126 bytes, checksum: 92c837eb39ae9af74c15ccf278cd2a84 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-03T16:39:11Z (GMT) No. of bitstreams: 1 fernandes_vjm_dr_prud.pdf: 25329126 bytes, checksum: 92c837eb39ae9af74c15ccf278cd2a84 (MD5) / Made available in DSpace on 2017-02-03T16:39:11Z (GMT). No. of bitstreams: 1 fernandes_vjm_dr_prud.pdf: 25329126 bytes, checksum: 92c837eb39ae9af74c15ccf278cd2a84 (MD5) Previous issue date: 2016-12-19 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Esse trabalho propõe o desenvolvimento de um método para a extração automática de contornos de telhados de edifícios com a combinação de dados de Varredura a LASER Aerotransportado (VLA) e dados fotogramétricos e campos aleatórios de Markov (MRF). Inicialmente, um Modelo Digital de Superfície normalizado (MDSn) é gerado através da diferença entre o Modelo Digital de Superfície (MDS) e o Modelo Digital de Terreno (MDT), obtidos a partir da nuvem de pontos LASER. Em seguida, o MDSn é segmentado para a obtenção dos polígonos que representam objetos altos da cena. Esses polígonos são projetados na imagem para restringir o espaço de busca para a segmentação da imagem em regiões. Esse processo possibilita a extração de polígonos na imagem que representem objetos altos. O processo de identificação de contornos de telhados, em meio aos objetos altos detectados na imagem, na etapa anterior, é realizado através da otimização de uma função de energia estabelecida com base em MRF que modela propriedades específicas de contornos de telhados de edifícios. No modelo MRF são utilizados tanto os polígonos extraídos da imagem quanto os extraídos dos dados VLA. A função de energia é otimizada pelo método Algoritmo Genético (AG). O método proposto nesse trabalho foi avaliado com base em dados reais - imagens aéreas de alta resolução e dados VLA. Os resultados obtidos na avaliação experimental mostraram que a metodologia funciona adequadamente na tarefa de extrair os contornos de telhados de edifícios. A função de energia proposta associada ao método de otimização AG diferenciou corretamente os contornos de telhados de edifícios dos demais objetos altos presentes nas cenas. Os contornos de telhados extraídos apresentam boa qualidade, o que é evidenciado por meio dos índices de completeza e correção obtidos pela avaliação numérica. Com base nos índices médios obtidos para cada experimento, têm-se as médias de completeza e correção para os experimentos iguais a 90,96% e 98,99%, respectivamente. Os valores máximos de completeza e correção são de 99,19% e 99,94%, respectivamente, e os valores mínimos de 78,08% e 97,46%, respectivamente. Os menores valores de completeza estão associados às áreas de oclusão por vegetação e presença de sombras. / This paper proposes a method for the automatic extraction of building roof contours through a combination of Airborne Laser Scanner (ALS) and photogrammetric data, and Markov Random Field (MRF). Initially, a normalized digital surface model (nDSM) is generated on the basis of the difference between the digital surface model and the digital terrain model, obtained from the LiDAR point cloud. Then the nDSM is segmented to obtain the polygons representing aboveground objects. These polygons are projected onto image to restrict the search space for image segmentation into regions. This process enables the extraction of polygons in the image representing aboveground objects. Building roof contours are identified from among the aboveground objects in the image by optimizing a Markov-random-field-based energy function that embodies roof contour specific properties. In the MRF model are used both polygons extracted from image and from ALS data. The energy function is optimized by the Genetic Algorithm (GA) method. The method proposed in this work was evaluated based on real data - high-resolution aerial images and ALS data. The results obtained in the experimental evaluation showed that the methodology works adequately in the task of extracting the contours of building roofs. The proposed energy function associated with the GA optimization method correctly differentiated the building roof contours from the other high objects present in the scenes. The extracted roof contours show good quality, which is evidenced by the indexes of completeness and correctness obtained by numerical evaluation. Based on the mean indexes obtained for each experiment, the average completeness and correctness for the experiments were equal to 90.96% and 98.99%, respectively. The maximum completeness and correctness values are 99.19% and 99.94%, respectively, and the minimum values are 78.08% and 97.46%, respectively. The lowest values of completeness are associated to the vegetation occlusion areas and presence of shadows. / FAPESP: 2012/22332-2
10

Cartographers : a practice based investigation on memory, conflict and the aerial image

Bonizzi, Valentina January 2016 (has links)
The power of the relationship between the photographic apparatus and migration is situated at a metaphorical crosslink between the two-dimensional outcome of marking borders on a map, or printing an image on a flat surface, and the time that affects the events that shape the very heart of that crosslink. The rigidity of borders, and sometimes their false ideas of flexibility can be seen on how recently Europe has proved (again) that ‘open boundaries’ is a non specific inclusive idea. The experience of migrants going through conflict situations is representative of the relationship between the ‘having to deal with’ the happenings, in most cases forced, and at the same time changing, transforming the landscape, leaving or bringing old and new values. Therefore the democratic power in this work is intended as the collective recognition of the importance of simple acts of looking, bringing values to the transformative nature of human beings. Because of its mechanical nature and the stillness of the images it produces, photography has the capacity to show transformation, with the quality of its materiality, which continuously challenges the users of photography in accessing different formats, since its invention. In the context of this work (Cartographers), photography becomes an inspiration for the concept, planning and making of the film process. Film can embrace elements that photography doesn’t have, like sound and duration, added to landscape and to portraits. These elements may help the viewer to understand a narrative that grows from a single trunk, the film, whose roots are holding onto the lightness of the sky instead of the thickness of the ground by representing, filmically, the expressions of the people who speak about their experiences. The ‘democratization of cartography’ – is in this written text considered as a shift of attention from the act of cartography to who makes it, the cartographers. Therefore map-making does not function as a merely two-dimensional outcome but as a nuance of an experience that is individual and collective. Cartographers reveals a map visible through the memory of a community of people who originate from the same place and have lived the same conflict (WWII) while being scattered across several different countries (Italy, France, Scotland). The work Cartographers, a film and series of archival aerial image, makes available the maps of these happenings, which memories are pulled together and suggest a reflection towards a democratic act of cartography making. The aim of this research is opposite to the creation of a cartography newly created by joining points from different journeys, experiences or concepts: in this work as the director of the film I have attempted to make emerge that the cartographers are aware of each other, their map is drawn collectively and everyday, and it does not join different points, but it starts from a single one and it explodes in different directions. The exploration of this work and research was made by attempting to represent what can be felt with the connection they have with the starting point. This is not only a process that looks at a certain community but is a dialogue with the memory of that community of cartographers which aids the understanding of the landscape that we traverse in our daily lives. With their memories, the subjects of the interviews - which I refer to as the Cartographers - leave a transparent but permanent trace that remains fixed in the landscape and makes it what it is today. The role of the artist in this case, is not the one of the ‘creator’ of a certain map, but the one that wipes the dust about to reveal the map of the treasure, and finds a way to show to the public, that the suspended moment of revelation, is the treasure itself.

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