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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.
1481

Modern Conservative Judicial Activism in the Supreme Court and the Entrenchment of Privilege as a Rights Claim

Mooradian, Carmen Beatriz B. 01 April 2013 (has links)
In this work , I analyze the emergence of a series of Supreme Court cases in the Rehnquist and Roberts era which frame race-conscious legislation as discriminatory against whites; and which are responded to by the conservative justices as though anticlassification and reverse-discrimination are indeed rights claims. I analyze the response of the conservative justices to such claims, and posit that response of the conservative Justices to such cases constitutes activism. Further, the emergence of these cases can be attributed to the entrenchment of a colorblind narrative that is by its very nature not grounded in social reality, or historical context; and which aims to elevate the privileges of whiteness into rights. The implications of these narratives and conservative judicial activism will have monumental consequences for minority populations of color in the country.
1482

Color Persistent Anisotropic Diffusion of Images

Freddie, Åström, Michael, Felsberg, Reiner, Lenz January 2011 (has links)
Techniques from the theory of partial differential equations are often used to design filter methods that are locally adapted to the image structure. These techniques are usually used in the investigation of gray-value images. The extension to color images is non-trivial, where the choice of an appropriate color space is crucial. The RGB color space is often used although it is known that the space of human color perception is best described in terms of non-euclidean geometry, which is fundamentally different from the structure of the RGB space. Instead of the standard RGB space, we use a simple color transformation based on the theory of finite groups. It is shown that this transformation reduces the color artifacts originating from the diffusion processes on RGB images. The developed algorithm is evaluated on a set of real-world images, and it is shown that our approach exhibits fewer color artifacts compared to state-of-the-art techniques. Also, our approach preserves details in the image for a larger number of iterations. / Original Publication:Åström Freddie, Felsberg Michael and Lenz Reiner, Color Persistent Anisotropic Diffusion of Images, 2011, Image Analysis, SCIA conference, 23-27 May 2011, Ystad Sweden, 262-272.http://dx.doi.org/10.1007/978-3-642-21227-7_25Copyright: Springer
1483

Segmentation Based Depth Extraction for Stereo Image and Video Sequence

Zhang, Yu 24 August 2012 (has links)
3D representation nowadays has attracted much more public attention than ever before. One of the most important techniques in this field is depth extraction. In this thesis, we first introduce a well-known stereo matching method using color segmentation and belief propagation, and make an implementation of this framework. The color-segmentation based stereo matching method performs well recently, since this method can keep the object boundaries accurate, which is very important to depth map. Based on the implemented framework of segmentation based stereo matching, we proposed a color segmentation based 2D-to-3D video conversion method using high quality motion information. In our proposed scheme, the original depth map is generated from motion parallax by optical flow calculation. After that we employ color segmentation and plane estimation to optimize the original depth map to get an improved depth map with sharp object boundaries. We also make some adjustments for optical flow calculation to improve its efficiency and accuracy. By using the motion vectors extracted from compressed video as initial values for optical flow calculation, the calculated motion vectors are more accurate within a shorter time compared with the same process without initial values. The experimental results shows that our proposed method indeed gives much more accurate depth maps with high quality edge information. Optical flow with initial values provides good original depth map, and color segmentation with plane estimation further improves the depth map by sharpening its boundaries.
1484

The Role of Concepts in Perception

Connolly, Kevin L. 19 January 2012 (has links)
The claim of my dissertation is that some basic concepts are required for perception. Non-basic concepts, we acquire, and I give an account as to how that process changes our perception. Suppose you are looking at the Mona Lisa. It might seem that you can perceive a lot more shades of color and a lot more shapes than for which you possess precise concepts. I argue against this. For every color or shape in appearance you have the ability to categorize it as that color or shape. It’s just that this is done by your sensory system prior to appearance. I argue that empirical studies show this. Blindsighted patients, for instance, are blind in part of their visual field. But they can use color and shape information received through the blind portion. I take this, along with other studies, to show that once you perceive a color or shape, it has already been categorized. I then argue that we perceive only low-level properties like colors and shapes. For in-stance, we don’t perceive high-level kind properties like being a table or being a wren. I do think that wrens or tables might look different to you after you become disposed to recognize them. Some take this to show that being a wren or being a table can be represented in your perception. I argue that this inference does not follow. If you are not disposed to recognize wrens, but we track the attention of someone who is, and we get you to attend to wrens in that same way, your visual phenomenology might be exactly the same as theirs. But there is no reason to think that it represents a wren. After all, you lack a recognitional disposition for wrens. I take this and other arguments to show that we perceive only low-level properties like colors and shapes.
1485

Association analysis of MC1R, MC4R and AGRP in beef cattle

McLean, Kim Lauren 13 January 2010
Three interrelated genes postulated to affect economically important traits related to growth and/or carcass quality of beef cattle were chosen to characterize and perform association analyses for this study. Melanocortin 1 receptor (MC1R), melanocortin 4 receptor (MC4R) and agouti related protein (AGRP) play an integral role in the appetite pathway and in fat deposition.<p> We genotyped 328 crossbred steers of various coat colours that were purchased at weaning and fed until slaughter for the previously published alleles ED, E+ and e. The E+ allele was present at five percent in this population and therefore was not included in further analysis. Black cattle of ED/ED or ED/e genotype had increased backfat (P<0.05) and required significantly fewer days (15-25) (P<0.01) on feed to reach a target fat level for slaughter compared to the red cattle. Red cattle of e/e genotype were found to have significantly larger longissimus dorsi (l. dorsi) area, shipping weight and hot carcass weight. Subsequent analysis revealed that the differences were comparable whether black versus red coat colour or MC1R genotype was used as the criteria for the group of cattle.<p> MC4R sequence was obtained from 20 random crossbred steers. In addition to several previously published polymorphisms, a novel Ser330Asn polymorphism was detected. A population of 382 crossbred Canadian steers and 985 crossbred American steers was genotyped for this Ser330Asn polymorphism. A minor allele frequency of 0.01 was observed in the Canadian and 0.02 in the American steer populations. No homozygous g.989AA cattle were detected. In the Canadian population, heterozygous steers had increased grade fat (P=0.036) and decreased lean meat yield (P=0.032). Similarly in the American population, steers of the g.989GA genotype had increased backfat (P=0.031) and less desirable yield grades (P=0.022,) but also lower ribeye area measurements (P=0.031). These results suggest that genotyping for the Ser330Asn polymorphism may lead to increased quality of carcasses either through lean meat production or backfat measurements, depending on the goal of the beef operation.<p> Sequence data obtained from 38 Bos taurus beef cattle, 4 Holsteins and 4 Bos indicus cattle revealed six polymorphisms in the AGRP gene. No polymorphisms that altered amino acids were detected in Bos taurus cattle. Genotyping of 382 crossbred beef steers was performed for two polymorphisms, an intronic deletion (g.439_440delTC) and a base pair substitution in exon 4 that did not alter an amino acid (g.715G>A). An ANOVA analysis, using PROC Mixed, was performed for both polymorphisms on several growth and carcass traits. No significant differences were observed.<p> Polymorphisms in MC1R and MC4R could be used as genetic tests which may be beneficial for beef producers in North America. The significant differences observed in this study in relation to cattle growth and fat deposition would represent savings for producers when used for sorting feedlot cattle or in selection of breeding cattle.
1486

The Role of Concepts in Perception

Connolly, Kevin L. 19 January 2012 (has links)
The claim of my dissertation is that some basic concepts are required for perception. Non-basic concepts, we acquire, and I give an account as to how that process changes our perception. Suppose you are looking at the Mona Lisa. It might seem that you can perceive a lot more shades of color and a lot more shapes than for which you possess precise concepts. I argue against this. For every color or shape in appearance you have the ability to categorize it as that color or shape. It’s just that this is done by your sensory system prior to appearance. I argue that empirical studies show this. Blindsighted patients, for instance, are blind in part of their visual field. But they can use color and shape information received through the blind portion. I take this, along with other studies, to show that once you perceive a color or shape, it has already been categorized. I then argue that we perceive only low-level properties like colors and shapes. For in-stance, we don’t perceive high-level kind properties like being a table or being a wren. I do think that wrens or tables might look different to you after you become disposed to recognize them. Some take this to show that being a wren or being a table can be represented in your perception. I argue that this inference does not follow. If you are not disposed to recognize wrens, but we track the attention of someone who is, and we get you to attend to wrens in that same way, your visual phenomenology might be exactly the same as theirs. But there is no reason to think that it represents a wren. After all, you lack a recognitional disposition for wrens. I take this and other arguments to show that we perceive only low-level properties like colors and shapes.
1487

Development of molecular markers for marker assisted selection for seed quality traits in oilseed rape

Rahman, Md. Mukhlesur 28 September 2007 (has links)
Molecular markers for seed quality traits including erucic acid content genes, seed coat color genes in Brassica napus and seed coat color genes in B. rapa were developed. A single base change in the Bn-FAE1.1 gene in the A genome and a two-base deletion in the Bn-FAE1.2 gene in the C genome produce the nearly zero content of erucic acid observed in canola. The single base change was detected as single nucleotide polymorphic (SNP) marker with an ABI SNaPshot kit. A multiplexing primer set was designed by adding a polyT to the 5´ primer end to increase SNP detection throughput through sample pooling. The two-base deletion in the C genome gene was detected as a sequence characterized amplified region (SCAR) marker in an ABI 3100 Genetic analyzer. To increase the throughput, one genome specific primer was labeled with four fluorescence dyes and combined with 20 different primers to produce PCR products with different fragment sizes. These multiplexed high throughput molecular markers have been successfully implemented in our canola/rapeseed breeding programs. Trigenic inheritance was observed for seed coat color in B. napus. Three Sequenced Related Amplified Polymorphism (SRAP) markers very closely linked to the three different seed coat color genes were developed. Chromosome-walking technology was used to convert the SRAP marker into a SCAR marker and a SNP marker. Subsequently, the first seed coat color gene (Bn1) marker was converted into a SCAR marker, and the second seed coat color gene (Bn2) marker was converted into a SNP marker. Digenic inheritance was observed for seed coat color genes in B. rapa. A SRAP marker was identified as being tightly linked to the major seed coat color gene (Br1). The SRAP marker was sequenced and extended sequences were obtained using chromosome-walking technology. The flanking sequences of the SRAP marker contained 24 SNPs and a 12-bp deletion position that allowed the marker to be converted into a co-dominant SNP marker and a co-dominant SCAR marker, respectively. The SCAR marker was detected in the ABI 3100 genetic analyzer with four fluorescently labeled M13 primers integrated with different SCAR primers, which permitted pooling of PCR samples for high throughput detection. / October 2007
1488

Estética en la pintura: El hecho de pintar

Carroggio de Molina, Alberto 06 March 1987 (has links)
En el ámbito de la Pintura Realista, es prácticamente imposible hallar documentos que, habiendo sido escritos por pintores, hagan referencia a su metodología.Por ello presentamos esta Tesis a modo de testimonio personal metodológico, dentro del campo del realismo pictórico.Iniciamos nuestra exposición con una aplicación estricta del concepto de color como sensación, y, ateniéndonos a ello, presentamos la sensación de color como un estado de conciencia, es decir, como sensación de color.En consecuencia, resulta imposible establecer valores objetivos de las nociones de luminosidad, pureza, valor cromático, equivalencia entre colores, etc., por lo que rechazamos tales propiedades referidas al color.En el marco de lo estrictamente pictórico, exponemos distintas opciones visuales que emanan de la superficie de trabajo o del modelo, la opción dependerá de las distintas pretensiones formales o de las condiciones personales del pintor. De ello se desprenden diversos resultados que justifican algunas de las diferencias pictóricas que se han producido en el Realismo.La noción de color como estado de conciencia supone, en un momento u otro del proceso, la creación de esta sensación, por lo que el color no es propiedad de los objetos, sino que es patrimonio exclusivo del sujeto que lo genera. Esta situación aplicada al resto de los sentidos nos conduce a un estado que podemos considerar como «autista» y que hemos denominado en un lenguaje algo rimbombante la soledad cósmica. Es decir, el individuo es creador del universo que le rodea, ya que éste surge a partir de las respuestas de los mecanismos. Estas son lo único que el individuo es capaz de concienciar y por tanto de conocer. De lo que se deduce que las categorías de las cosas vienen determinadas por tales mecanismos y no por la cosa en sí tomada como algo ajeno a nosotros.Por ello, el hecho de pintar, sujeto a tales mecanismos, tanto visuales como conceptuales, es una consecuencia de los mismos. Así pues, cuanto más nos ajustemos a las premisas de tales mecanismos, más correcto será nuestro trabajo como pintores.Pretendemos además, con nuestra Tesis, iniciar una línea de investigación abierta a nuevos comunicados de otros pintores y de esta forma conseguir un banco de datos, con suficiente fundamento teórico, que permita la elaboración de conclusiones definitivas sobre los procesos de la pintura realista.
1489

Extracción de compuestos fenólicos de la uva al vino. Papel de los enzimas de maceración

Romero Cascales, María Inmaculada 23 May 2008 (has links)
La extracción de los compuestos fenólicos, responsables de ciertas características de color de los vinos, va a depender entre otros, de la degradación de la pared celular, por lo que el uso de enzimas pectolíticos podría ser una técnica adecuada para obtener vinos con mayor carga polifenólica. Los resultados mostraron que la extracción de los compuestos fenólicos durante la maceración es incompleta. Además, estudiando la extractabilidad de los compuestos fenólicos en diferentes variedades se observó que ciertos parámetros indicativos de la madurez fenólica de la uva y de la composición de la pared celular de los orujos pueden ayudar a predecir algunos de los parámetros cromáticos más importantes en el vino. El estudio de la aplicación de enzimas comerciales, mostró que, dependiendo de las características de la uva y el tiempo de maceración, los resultados obtenidos varían, por tanto el uso de éstos estará en función de la uva a vinificar. / The extraction of phenolic compounds, main responsibles of wine color, will depend on the degradation of the cell wall, so the use of pectolytic enzymes could be a suitable technique for obtaining wines with greater polyphenol cotent.The results showed that extraction of phenolic compounds during the maceration is incomplete. In addition, studying the extractability of phenolic compounds in different varieties, it was observed that certain parameters indicative of phenolic ripeness of the grapes and the composition of the cell wall of the marc can help to predict some of the most important color parameters in wine. The application of commercial enzymes showed that depending on the characteristics of the grapes and how long the maceration process is, the results vary, therefore their use will depend on the characteristics of the grapes and the vinification process.
1490

Heat transfer and fluid-dynamics in double and single skin facades

Faggembauu, Débora 19 December 2006 (has links)
Una proporción muy importante del presupuesto energético total de los países europeos es destinado al consumo energético del sector de la edificación, tanto en el ámbito doméstico como terciario. Debido a que esta tendencia continúa en aumento, es de vital importancia optimizar los edificios tanto desde el punto de vista de las envolventes térmicas, como de las instalaciones térmicas y las condiciones de operación y funcionamiento.Esta tesis incide fundamentalmente en el diseño eficiente de la fachada, ya que éste es uno de los principales elementos que determinan el comportamiento térmico de los edificios. No sólo actúa como barrera entre las condiciones externas e internas, sino que el diseño eficiente de la misma, contribuye en forma relevante a la reducción del consumo de calefacción, aire acondicionado, ventilación e iluminación. Asimismo, es un elemento que incide notablemente en las condiciones de salubridad y confort. Actualmente, existe un gran auge del uso de fachadas completamente hechas de vidrio, este tipo de construcción presenta una serie de ventajas arquitectónicas y estéticas, pero desde el punto de vista térmico pueden representar problemas de sobrecalentamientos y pérdidas de energía importantes, tanto en las áreas mediterráneas como en otras zonas climáticas. En este sentido, las fachadas de doble piel, compuestas por dos capas separadas por un canal de aire, usado para evacuar o aprovechar la energía solar absorbida por la fachada, pueden representar una opción de diseño válida para solventar esta problemática. Asimismo, este tipo de diseño puede producir unas condiciones de confortabilidad adecuadas debido a la reducción de las temperaturas de las superficies interiores de las fachadas.El objetivo de esta tesis es el de contribuir al estudio de sistemas pasivos en general, y fachadas avanzadas en particular. Para ello, se ha desarrollado una herramienta numérica para la simulación de fachadas de edificios de simple y doble piel. La principal característica de este código es la de asumir un comportamiento unidimensional y transitorio. Las ecuaciones gobernantes (continuidad, momentum y conservación de la energía) son resueltas mediante la aplicación del método de volúmenes finitos. Las fachadas incluyen elementos arquitectónicos novedosos, como materiales de cambio de fase, aislamiento transparente, superficies selectivas y colectores solares con acumuladores integrados en la superficie de las fachadas. En la tesis, se describen las características de los modelos físicos y matemáticos implementados y se definen parámetros instantáneos e integrados que describen el comportamiento térmico de las fachadas. Los modelos numéricos implementados han sido sujetos a procesos de verificación y validación en diferentes formas: i) por comparación de los resultados numéricos con los obtenidos para situaciones simplificadas que cuentan con solución analítica, ii) por comparación con parámetros globales tabulados en la literatura de ciertas configuraciones de fachadas, y iii) por comparación de los resultados numéricos con los obtenidos experimentalmente en celdas de ensayo sometidas a diferentes condiciones climáticas.Se presentan resultados de estudios paramétricos de diferentes configuraciones de fachadas y aplicaciones del código numérico para la optimización del diseño de fachadas de edificios emblemáticos del entorno. Como acciones futuras, se prevé la conexión de este tipo de simulaciones con otras de más alto nivel, bidimensionales, para optimizar zonas concretas de las fachadas. / A significant proportion of the total national energy budget of european countries goes toward energy consumption in buildings, therefore the efforts addressed to optimize building's thermal behaviour are of vital importance. In this sense, facades play a fundamental role. Not only do they act as barriers between external and internal conditions, but they can also help to reduce the consumption of energy for heating, ventilation and air conditioning. Moreover, they can help to produce healthy and comfortable indoor conditions. The use of large, transparent areas in facades is a common current practice. Despite the architectural interest of these glazed areas, in Mediterranean climatic conditions they are responsible for building overheating. In these zones, double-skin envelopes made up of two layers of glass separated by an air channel -to collect or evacuate the solar energy absorbed by the facade- are considered to be a design option that could resolve this issue. In other climatic conditions, large heat losses may constitute the most determinant factor. Anyway, the comfort parameters are influenced by the large transparent areas, also in this design aspect, double skin facades may contribute to obtain more comfortable and pleasant living spaces.The objectives of this thesis are to give a step forward in the study and numerical analysis of passive systems in general, and advanced facades in particular. A one-dimensional and transient numerical code for the simulation of double and single skin facades including advanced technological elements, like phase change materials, transparent insulation and facade integrated collectors-accumulators has been developed. The features of the physic and mathematical models implemented are described and instantaneous or integratedperformance parameters describing thermal behaviour of the facades are defined. The numerical models implemented within the numerical tool have been subjected to a verification and validation process in different forms: by comparing the numerical results with those obtained for simplified situations with analytical solutions, with tabulated global performance coefficients of simple façade configurations and with the results of other building simulation codes. Experimental research has been carried out in test cells situated at different geographical locations, thus they were subjected to different climatic conditions. The main objective of the developed numerical code is to simulate advanced facades in order to assess the long term performance, and to account with a virtual tool to test passive designs, including challenging innovations.The applications of the numerical tool described in this thesis, for the optimisation of facades of real buildings are presented. As future actions, the link of the one-dimensional simulations produced by this numerical tool with a multi-dimensional simulation of specific zones of the facades is foreseen.

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