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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.
1271

THE RELATIONSHIP OF THE MUNSELL SOIL COLOR WITH THE LANDSAT SPECTRAL BANDS.

Rodriguez-Morean, Alfonso Luis. January 1982 (has links)
No description available.
1272

Colour-singlet exchange and tests of models of diffractive DIS

Williams, Jennifer C. January 2000 (has links)
No description available.
1273

Caracterización de genes vinculados al crecimiento y al color de capa en la Llama (Lama glama)

Daverio, María Silvana 01 October 2014 (has links)
La Llama es el Camélido doméstico más abundante de Argentina. La cría de Llamas constituye una actividad económica de gran importancia debido a que es una especie poliproductora de carne, fibra, cuero y transporte. Actualmente existe interés creciente por mejorar el rendimiento y calidad de estos productos. El estudio de genes candidatos permite vincular las variaciones de un carácter y la manera en que éste se manifiesta en el fenotipo del individuo. En ese contexto la hormona de crecimiento (GH), producto del gen GH1 y secretada por la glándula pituitaria, estimula el crecimiento de huesos y músculos. Por otra parte, es bien conocido el interés que existe en la producción de fibras por determinados colores con mayor valor comercial. La determinación del color de capa en mamíferos se debe a la interacción de los genes MC1R (receptor 1 de melanocortina) y ASIP (péptido de señalización Agouti). Ambos controlan el tipo y localización de pigmento eumelánico (negro-marrón oscuro o sepia) o feomelánico (rojoamarillento) producido. Esta Tesis tuvo por objetivo caracterizar y analizar la diversidad genética del gen GH1 y realizar la caracterización molecular de las variantes alélicas de MC1R y ASIP en Llamas con distintos fenotipos de colores de capas. Mediante PCR se amplificaron y luego secuenciaron los tres genes. El gen GH1 mostró un alto nivel de variabilidad encontrándose 15 SNPs, mayormente situados en región no codificante. Sin embargo se identificaron dos polimorfismos en el promotor y uno en la región 5´no traducible. Dado que los polimorfismos localizados en el promotor podrían afectar los niveles de expresión del gen, se concluye que los mismos pueden ser útiles en futuros estudios de asociación. Con respecto al gen MC1R se identificaron 13 SNPs en región codificante, 10 de los cuales fueron no sinónimos. La combinación de 3 de estos polimorfismos permitieron diferenciar Llamas con capas pigmentadas (A259/A376/T383) de las blancas no albinas (BNA) que carecían de pigmento (G259/G376/C383). En ASIP el hallazgo más importante fue una deleción de 57pb en el Exón 4 con posible pérdida de función. De esta manera, el alelo delecionado en homocigosis se observó en Llamas eumelánicas y el alelo sin delecionar en estado homocigota o heterocigota, se vió en Llamas feomelánicas. La identificación de los alelos de los genes MC1R y ASIP permitió proponer un mecanismo por el cual se genera la pigmentación feomelánica y eumelánica (TO) en las Llamas.
1274

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.
1275

Simulation motrice et perception d'objets manipulables : quand l'action potentielle contribue à l'identification de la couleur / Motor simulation and perception of graspable objects : when potential action contribute to the identification of the color

Ferrier, Laurent 17 June 2011 (has links)
L’effet de potentialisation motrice, initialement décrit par Tucker et Ellis (1998), correspond au bénéfice entrainé par l’action potentielle évoquée par la perception d’objets manipulables en lien avec le dispositif de réponse. Cet effet a été observé dans de nombreux contextes expérimentaux. Toutefois, il semble que cet effet ne s’observe pas lorsque la tâche des participants ne porte pas directement sur une caractéristique requise pour le contrôle de l’action (Tipper, Paul & Hayes, 2006) ou qui n’entraîne pas suffisamment d’attention sur l’objet (Ellis, Tucker, Symes & Vainio, 2007 ; Symes, Ellis & Tucker, 2005). Le cas particulier de l’identification de la couleur est un exemple dans lequel cet effet n’est généralement pas constaté (Symes et al. 2005 ; Tipper et al. 2006). En s’appuyant sur des travaux qui proposent une alternative aux théories dissociatives classiques du système visuel (Creem & Proffitt, 2001 ; Frey, 2007 ; Young, 2006 ; Derbyshire, Ellis & Tucker, 2006) et qui se basent essentiellement sur des processus de résonance motrice et de simulation comme condition nécessaire à l’identification et à la reconnaissance (Rizzolatti & Matelli, 2003 ; Bar, 2007 ; Berthoz & Petit, 2003), cette thèse a pour objet de spécifier les conditions d’observation du phénomène de potentialisation motrice en tâche d’identification chromatique. Pour ce faire, nous avons adapté le paradigme SRC modifié de Tucker et Ellis (1998) et le protocole d’amorçage développé par Phillips et Ward (2002) à l’étude de l’identification des couleurs d’objets manipulables. Les résultats que nous avons obtenus montrent une interaction entre l’identification de la couleur et les simulations motrices associées à la perception d’objets manipulables. Ces résultats sont discutés en faveur des modèles qui cherchent à réconcilier les approches écologiques et représentationnelles de la perception ainsi que de ceux qui insistent sur la nature profondément proactive et simulationniste du système perceptif. / Potentiation of action effect, originally described by Tucker and Ellis (1998), corresponds to the advantage led by action evoked by the perception of graspable objects related to the response device. These effects have been reported for many experimental conditions. However, this effect is not observed when the task is not directly about a characteristic required for action control (Tipper, Paul & Hayes, 2006) or when it does not allowed for enough attention on the object (Ellis, Tucker, Symes & Vainio, 2007; Symes, Ellis & Tucker, 2005). Color perception and identification is a particular case where these effects are generally not observed (Symes et al. 2005; Tipper et al. 2006). Relying on recent works that propose an alternative to theories of classic dissociation of the visual system (Creem & Proffitt, 2001; Frey, 2007; Young, 2006; Derbyshire, Ellis & Tucker, 2006) and that are essentially based on motor resonance and simulation processes as a condition to identification and recognition (Rizzolatti & Matelli, 2003; Bar, 2007; Berthoz & Petit, 2003), this thesis aims to specify the conditions of observation of a potentiation of action phenomenon in a chromatic identification task. To that end, we have adapted the SRC paradigm (stimulus response compatibility) modified by Tucker and Ellis (1998) and the priming paradigm developed by Phillips and Ward (2002) to study color identification of graspable objects. Results we obtain shows an interaction between the identification of color and the motor simulations associated with the perception of graspable objects. We discuss our results in the light of models which tend to reconcile ecological and representational approaches of perception as well as those which insist on the deeply proactive and simulationist nature of the perceptual system.
1276

FAST FRIENDS: IMPLICIT BIAS OF CROSS-GROUP FRIENDSHIPS IN A COLLEGE OF AGRICULTURE

Harper, Tiffany 01 January 2017 (has links)
Cross-group paired individuals were administered an intervention to measure impacts of inmate interactions and friendships on anxiety and implicit bias among participants. Researchers predicted the intervention would decrease levels of racial anxiety, implicitness, prejudice, and racial color-blindness among entering freshmen in the College of Agriculture, Food & Environment at the University of Kentucky. Results indicated that the control group had no change in implicitness. The treatment group yielded no change in implicitness on four out of five experimental measures with the exception of decrease in communal orientation, thus altering the implicit bias of participants.
1277

Ethical Decisions in Two Different Works of Charles Waddell Chesnutt

Bokhari, Shuaa Abdulrashid 16 December 2016 (has links)
Chesnutt's short stories collection The Wife of His Youth and Other Stories of the Color Line (1899). Charles Chesnutt wrote two short stories which are "The Sheriff's Children" and "Her Virginia Mammy." He wrote them with white audiences in mind. In “The Sheriff’s Children,” Chesnutt presents Tom as a protagonist, his father Sheriff Campbell, and his half-sister Polly. In “Her Virginia Mammy,” he mentions Clara as a protagonist, her love Dr. Winthrop, and her mother Mrs. Harper. Chesnutt records their struggles in Post-Reconstruction North Carolina. He romanticized his characters’ difficult ethical decisions related to racial identity to illustrate more dramatically the consequences of their oppression. “The Sheriff’s Children” and “Her Virginia Mammy” both illustrate the ethical dilemmas of their protagonists, demonstrating to Chesnutt’s white readers the struggles and losses of black and biracial families.
1278

Interactions Among Multiple Plastic Traits in Caterpillar Thermoregulation

Nielsen, Matthew Erik, Nielsen, Matthew Erik January 2016 (has links)
Adaptive phenotypic plasticity is a key mechanism by which organisms deal with variation in many different aspects of their environment. Adaptive plasticity can occur in any trait, from aspects of biochemistry and morphology to behaviors. Because so many different traits can be plastic, organisms often respond plastically to a given change in their environment, such as an increase in temperature, with adaptive changes in multiple traits. Nevertheless, how these different plastic responses interact with each other and evolve together has received little attention. My research addresses these potential interactions among plastic traits and proposes new hypotheses regarding the causes and consequences of these interactions. It does so by focusing on heat avoidance in the caterpillars of Battus philenor (the pipevine swallowtail) which involves two distinct plastic mechanisms. First, the caterpillars can change color when they molt, a form of morphological plasticity in which they develop a red color under high temperatures which cools them by absorbing less solar radiation. Second, when the caterpillars become too hot, they will leave their host to seek cooler thermal refuges, a case of behavior as a form of plasticity. In terms of function, I demonstrated through field research that these two responses to high temperatures are largely redundant. Behavior provides a much stronger and faster response than color change, and red coloration provides little additional cooling when on a refuge. Instead, the primary benefit of color change is that it reduces the use of refuge seeking behavior, allowing the caterpillars to stay on their hosts longer. Using laboratory experiments, I demonstrated that this change in the use of refuge-seeking behavior with color occurs because color changes the cue for the behavior, body temperature, rather having any effect on how the caterpillar responds to that cue. Alternatively, similar experiments on caterpillars of varying sizes show that developmental size change lowers the body temperature at which caterpillars leave their host, demonstrating a change in the response to the cue (although larger caterpillars are also warmer, so both mechanisms are likely relevant for how size changes the expression of behavior). All of my research to this point was conducted on the local population in southern Arizona, which experiences quite high temperatures, but B. philenor is also found in much cooler environments, such as the Appalachian Mountains. Given this variation in their thermal environment, I used common garden experiments to compare the capacity for color change and refuge-seeking among B. philenor caterpillars from across the species range. Both color change and refuge seeking not only occurred in all populations, but also had the same reaction norms, occurring at the same temperatures and to the same degree. This is particularly notable for color change, which is not observed in the wild in northeastern populations, and thus has persisted despite minimal if any use. Overall, I have shown that studies of plasticity need to account for plasticity in different traits as well as the interactions between these forms of plasticity. My research on B. philenor provides a model for how to address these interactions, which future research can extend to additional organisms and environmental circumstances.
1279

Uppfattningen av den grafiska designen på teförpackningar : Enkätundersökning och visuell innehållsanalys / The perception of the graphic design of tea packages : Survey and visual content analysis

Andrén, Sandra, Man, Nicole January 2016 (has links)
Idag konkurrerar företagen om att sälja lika produkter, därför är det viktigt att sticka ut och inte smälta in i mängden. I butikerna finns det stor variation av förpackningar och därför har den grafiska designen en betydelsefull roll. Denna studie undersöker teförpackningens grafiska design och om den grafiska designen på teförpackningar har en inverkan på hur konsumenten uppfattar produkten. Denna studie är endast inriktad på teförpackningar som innehåller tepåsar och inte löste i förpackning. Fokus ligger på den grafiska designen på teförpackningens framsida och inte formen av förpackningen. Studien har genomförts med en enkätundersökning och en visuell innehållsanalys. Studien syftar till att ta reda på vad det är i teförpackningens grafiska design som bidrar till hur konsumenten uppfattar produkten. Resultatet av undersökningen visade att produktens märke hade en stor betydelse på hur konsumenten uppfattade produkten och dess design. / The companies of today all compete to sell the same products and it’s important to stand out. There’s a great variety of packaging in the stores and that’s why graphic design play an important role. This study examines the graphic design of the tea packaging and if graphic design on tea packages has an impact on how consumers perceive the product. This study is only focused on tea packages containing tea bags and not loose tea. The focus is on graphic design on the front of the tea package and not the shape of the tea package. The study was implemented with a survey and a visual content analysis. The study aims to find out what it is in the tea packaging graphic design that contributes to how the consumer perceives the product. The results of the survey showed that the brand had a big impact on how consumers perceived the product and its design.
1280

Handheld and robotic phenotyper designs

Wei, Yong January 1900 (has links)
Doctor of Philosophy / Department of Biological & Agricultural Engineering / Naiqian Zhang / One of precision agriculture researches currently focuses on the relationship between plant phenotype, genotype, and ambient environment, including critical investigations of a multi-sensor-integrated phenotyping platform and data mining technology for big data. This study examined the designs of two phenotyping platforms and developed machine vision (MV) technology to estimate wheat growth status and count wheat head. The GreenSeeker, an infrared thermometer (IRT), a web camera, and a global positioning system (GPS) receiver were integrated into one handheld phenotyping platform, named as Phenocorn. The Phenocorn allowed simultaneous collection of the normalized difference vegetative index (NDVI) and canopy temperature (CT) with precise assignment of all measurements to plot location by GPS data points. The Phenocorn was tested using a field trial of 10 historical and current elite wheat (Triticum aestivium) breeding lines at the International Maize and Wheat Improvement Center (CIMMYT) in Ciudad Obregon, Mexico, during the 2013 and 2014 growing seasons. Results showed that the NDVI data, PVC (percent vegetation coverage) data, and temperature data obtained by the handheld phenocorn could availably reflect the wheat growing status in the field, and the handheld phenocorn could be used as an instrument to do plant phenotyping information collection. This study also used the modular design method to design the mechanical structures of a robot-based phenotyping platform, named as Phenorobot. Its control system was based on a Controller Area Network (CAN bus). The basic function performances such as steering function, lifter load, and movement features were tested in the laboratory. Proposed design indicators were achieved, demonstrating its potential utilization for field experiments. Image acquisition is one of the main data collection methods for plant phenotyping research. The method for extracting plant phenotyping traits based on MV was explored in this research. Experiments for detecting the wheat development based on the images taken in the field were designed and carried out from March to June 2015, and a method based on color analysis to estimate percent vegetation coverage (PVC) of wheat was developed. A wheat growth model based on the PVC was used for the wheat growth status analysis. In addition, a wheat head counting method was developed and divided into three steps: wheat head image segmentation, leaf debris elimination, and wheat head counting. This paper proposes the first wheat head counting model (WCM) based on the pixels group measurement of wheat heads. Compared to the Joint Points Counting (JPC) method (Liu et al., 2014) and the Wheatear Shape Index (WSI) method (Frédéric et al., 2012), the WCM more accurately counted wheat heads from images taken in the experiments.

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