Tesis:

1

Akcelik, Mustafa. "Improving Remotely-sensed Precipitation Estimates Over Mountainous Regions". Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12615666/index.pdf.

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In support of the National Oceanic and Atmospheric Administration (NOAA) National Weather Service&rsquo
s (NWS) flash flood warning and heavy precipitation forecast efforts, the NOAA National Environmental Satellite Data and Information Service (NESDIS) Center for Satellite Applications and Research (STAR) has been providing satellite based precipitation estimates operationally since 1978. Two of the satellite based rainfall algorithms are the Hydro-Estimator (HE) and the Self-Calibrating Multivariate Precipitation Retrieval (SCaMPR). Satellite based rainfall algorithms need to be adjusted for the orographic events and atmospheric variables for the continued improvement of the estimates. However, unlike the HE algorithm, the SCaMPR does not currently make any adjustments for the effects of complex topography on rainfall estimate. Bias structure of the SCaMPR algorithm suggests that the rainfall algorithm underestimates precipitation in case of upward atmospheric movements and high temperature levels. Also SCaMPR algorithm overestimates rainfall in case of downward atmospheric movements and low temperature levels. A regionally dependent empirical elevation-based bias correction technique and also a temperature based bias correction technique may help to improve the quality of satellite-derived precipitation products. In this study, an orographic correction method and a temperature correction method that will enhance precipitation distribution, improve accuracy and remove topography and temperature dependent bias is developed for the Self-Calibrating Multivariate Precipitation Retrieval (SCaMPR) rainfall algorithm to be used in operational forecasting for meteorological and hydrological applications.

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2

Medeiros, Nathalia Maira Cabral de. "An?lise filogen?tica e funcional de dois genes de reparo hom?logos a AP endonuclease em cana-de-a??car: ScARP1 e ScARP3". Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12627.

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Made available in DSpace on 2014-12-17T14:03:44Z (GMT). No. of bitstreams: 1 NathaliaMCM_DISSERT.pdf: 2544480 bytes, checksum: eab320fea2fc6e6b04c8d45099041a93 (MD5) Previous issue date: 2014-03-21
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The genome of all organisms constantly suffers the influence of mutagenic factors from endogenous and/or exogenous origin, which may result in damage for the genome. In order to keep the genome integrity there are different DNA repair pathway to detect and correct these lesions. In relation to the plants as being sessile organisms, they are exposed to this damage frequently. The Base Excision DNA Repair (BER) is responsible to detect and repair oxidative lesions. Previous work in sugarcane identified two sequences that were homologous to Arabidopsis thaliana: ScARP1 ScARP3. These two sequences were homologous to AP endonuclease from BER pathway. Then, the aim of this work was to characterize these two sequence using different approaches: phylogenetic analysis, in silico protein organelle localization and by Nicotiana tabacum transgenic plants with overexpression cassette. The in silico data obtained showed a duplication of this sequence in sugarcane and Poaceae probably by a WGD event. Furthermore, in silico analysis showed a new localization in nuclei for ScARP1 protein. The data obtained with transgenic plants showed a change in development and morphology. Transgenic plants had slow development when compared to plants not transformed. Then, these results allowed us to understand better the potential role of this sequence in sugarcane and in plants in general. More work is important to be done in order to confirm the protein localization and protein characterization for ScARP1 and ScARP3
O genoma de todos os organismos sofre constantemente a influ?ncia de fatores mutag?nicos que podem ser de origem end?gena e/ou ex?gena, estes podem resultar em danos ao material gen?tico. Se esses danos n?o forem corrigidos pode levar ao aparecimento de muta??es. As plantas por serem organismos sesseis est?o continuamente expostas a estes fatores. Considerando isto, os organismos (animais e vegetais) possuem diferentes vias de reparo de DNA para manter a integridade do material gen?tico. Dentro destas vias, h? a via de Reparo por Excis?o de Bases (BER) que ? composta por diferentes enzimas, e dentro dessa via h? a enzima AP endonuclease que ? alvo deste estudo. Trabalhos anteriores em cana-de-a??car identificaram duas sequ?ncias de cDNA hom?logas a esta prote?na que foram denominadas ScARP1 e ScARP3. Com isso, o objetivo deste trabalho foi caracterizar estas duas sequ?ncias por meio de an?lises filogen?ticas utilizando sequ?ncias presentes dentro do reino Plantae, e de an?lises estruturais dos genes de AP endonuclease por an?lise in silico e por plantas transg?nicas contendo cassetes de super-express?o. Al?m disso, foi realizado transforma??es e a obten??o plantas transg?nicas de Nicotiana tabacum contendo cassetes de super-express?o em orienta??o anti-senso. Foi tamb?m analisado a rela??o filogen?tica de genes DNA ligase I presentes no organismo vegetal de estudo. Os resultados obtidos permitiram verificar que as sequ?ncias ScARP1 e ScARP3 correspondem a uma duplica??o, provavelmente devido a um processo de duplica??o do genoma como um todo (WGD) que deve ter ocorrido no grupo das gram?neas (Poaceae). Refor?ando estes dados, foi verificado um poss?vel direcionamento da prote?na para organelas diferentes, sendo que a ScARP1 pode ser encontrada no n?cleo e a ScARP3 em mitocondrias e/ou cloroplasto. Com rela??o as plantas transg?nicas contendo o cassete em orienta??o anti-senso foi observado que estas apresentaram crescimento lento quando comparado com a planta selvagem (n?o transformada). Al?m disso, seu fen?tipo abrange altera??es morfol?gicas no crescimento foliar, baixa estatura e diminui??o na produ??o de sementes. Entretanto, ainda se faz necess?rio a obten??o da linhagem homozigota para aprofundar essas observa??es. Desta forma, estes resultados permitem compreender um pouco melhor do poss?vel papel da enzima AP endonuclease em cana-de-a??car e em plantas

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3

Rodrigues, Rodrigues Carlos Saulo Borges Carlos Saulo Borges. "O espaço intersticial entre a casa e a escarpa : a propósito do parque natural do Rio Seco". Master's thesis, Universidade de Lisboa. Faculdade de Arquitetura, 2014. http://hdl.handle.net/10400.5/7806.

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Dissertação para obtenção do grau de Mestre em Arquitetura, apresentada na Universidade de Lisboa - Faculdade de Arquitetura.
Este trabalho pretende analisar a reestruturação do vale do Rio Seco e qual o papel das maquetes no processo explorativo inerente à resolução de potenciais problemas a esse nível. É feito um estudo sobre os diferentes conceitos associados ao ato de desenhar: cidade e habitação, sendo feita uma análise centrada em algumas das ideias chave do arquiteto Le Corbusier. São abordados os diferentes planos urbanos por ele elaborados dentro da lógica da “Ville Radieuse” e a sua ideia de Unidade de Habitação e Célula Habitacional (o espaço mínimo). Complementarmente, faz-se uma alusão à perceção das suas obras a partir do ponto de vista dos seus habitantes. A partir das ideias de Le Corbusier, apresenta-se uma leitura de casos de estudo ligados à temática da habitação coletiva e dos planos urbanos. Ainda a respeito da temática da habitação coletiva, abordamos de alguns estudos de caso que fazem parte do panorama internacional e nacional, falando de arquitetos tais como: Herzog e De Meuron, Charles Correia, Teotónio Pereira entre outros. Uma boa leitura do local de intervenção e da sua envolvente assume também grande importância neste caso. A escarpa apresenta-se como um elemento natural de relevo no local de intervenção e carece de uma solução que a enobreça. É feita uma leitura histórica e geológica deste espaço tão nobre para percebermos quais as suas qualidades naturais. Por fim, a proposta projetual é explorada e apresentada. O recurso a diferentes maquetes é muito marcante pela facilidade de manipulação e pela leitura imediata que este processo apresenta.
ABSTRACT: This work pretends to analyze the process of restructuring the valley of Rio Seco and how the architectural models can help to solve that problem. A study is done about the different concepts concerning the act of drawing cities and homes. It’s made an analysis of the different ideas that came from the architect Le Corbusier. The several urban plans made by him are studied inside the idea of the “Ville Radieuse” and its plans to create a Residential Unit and a Cell Housing (minimum space). As a complement, is made an analysis of the perception of its works from the point of view of its inhabitants. From Corbusier ideas, is also made a reading of recent national and international study cases that come from other architects such as Herzog and De Meuron, Charles Correia, Teotónio Pereira among others. In this case, a good reading of the working site and its surroundings is also extremely important. The scarp presents itself as a natural element of relief in the intervention site and is in need of a solution that ennobles her. It’s made an historical and geological reading of this noble space for us to understand and observe its natural qualities. Lastly, the projetual proposition is explored and presented. The use of several models is very important because of its easy handling and instant reading that the process presents.

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4

Behnamian, Amir. "Experimental Studies of Scalar Transport and Mixing in a Turbulent Shear Flow". Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33167.

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High resolution, multi-sensor, hot/cold-wire measurements were made in passively heated, uniformly sheared turbulence in a wind-tunnel. Measurements were focused on terms that are important for modelling of the scalar probability density function (PDF) equation. Unlike previous studies, which considered a single combination of velocity and scalar fields at a time, in this study three different scalar fields were investigated in the same nearly homogeneous turbulence with three passively superimposed temperature fields, namely a transversely homogeneous temperature field with a uniform mean gradient, and two inhomogeneous temperature fields, the plume of a heated line source and a thermal mixing layer. The use of the same uniformly sheared flow allowed the isolation of the effects of scalar inhomogeneity and initial conditions by evaluating the results in the three scalar fields. Thus, the measurements covered a wide range of scalar field conditions and set the ground for a conclusive comparison. For the homogeneous scalar field, results conformed with the literature: the scalar PDF was essentially Gaussian; the conditional expectations of velocities upon the scalar value were approximately linear; and the conditional expectation of the scalar dissipation rate upon the scalar value was mildly anisotropic and had a shape that was similar to those of any of its three parts, which justifies the use of the streamwise part as a surrogate for the total. All these properties behaved very differently in two inhomogeneous scalar fields, the thermal mixing layer and the plume of a heated line source: the scalar PDFs were distinctly sub-Gaussian; the conditional velocity expectations were non-linear functions of the scalar value; and the conditional scalar dissipation rates were very strongly anisotropic, as well as depending on the scalar value in fashions that differed strongly from those of any of their three parts.

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5

Kujat, Jens. "Scalar fields in cosmology". Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1142978764.

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6

Ashcroft, P. R. "Cosmology with scalar fields". Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.596177.

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In this thesis we investigate a number of roles that scalar fields can play in cosmology. In particular it is generally believed that the early Universe underwent a period of very rapid expansion. We call this epoch inflation. Initially we investigate the evolution of two slow-rolling scalar fields with potentials of the form V = V_oφ^-^a exp(-bφ^m). By considering different values of the parameters a, b and m, we drive several new inflationary solutions in which one field just evolves in the background and is not important for the inflationary dynamics. In addition, we find new solutions where both fields are dynamically important during inflation. Moreover, we discuss the evolution of perturbations in both the scalar fields and the spacetime metric, concentrating on the production of entropy perturbations. We find that for a large region in parameter space and initial conditions, tensor modes are negligible, and that adiabatic and isocurvature perturbations are essentially uncorrelated. We move on to consider perturbations in the Randall-Sundrum braneworld scenario. At energies higher than the brane tension, the dynamics of a scalar field rolling down a potential are modified compared with the predictions of General Relativity. These modifications imply, among other things, that steeper potentials can be used to drive an epoch of slow-roll inflation. The evolution of entropy and adiabatic modes during inflation driven by two scalar fields confined to the brane is studied. We show that the amount of entropy perturbation produced during inflation is suppressed compared to the predictions made by General Relativity. As a consequence, the initial conditions do not matter in multiple field inflation in braneworlds if inflation is driven at energies much higher than the brane tension. Following this, we study the evolution of slow-roll inflation in a five-dimensional braneworld model with two boundary branes and a bulk scalar field. Assuming that the inflationary scale is below the brane tension, we can employ the moduli space approximation to study the dynamics of the system. Detuning the brane tension results in a potential for the moduli fields which we show will not support a period of slow-roll inflation. We then study an inflation field confined to the positive tension brane, to which the moduli fields are non-minimally coupled. We discuss in detail the two cases of V (χ) = ½m² χ² and V (χ) = l χ⁴ and demonstrate that increasing the coupling results in spectra which are further away from scale-invariance. Furthermore, there is an increase in the tensor mode production, while entropy perturbations are subdominant. Finally, we point out that the five-dimensional spacetime is unstable during inflation because the negative tension brane collapses.

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7

Davies, Trevor Bamidelé. "Quadratic scalar-tensor gravity". Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=234075.

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This thesis develops novel analytic models of scalar-tensor theories with quadratic coupling. In this framework, the coupling strength between scalar and matter is regulated in a way that allows the vacuum expectation value to vanish for low matter densities while becoming non-vanishingly large in the high-density regime. This results in significant deviations from the predictions of General Relativity in the strong-gravity regime. In astrophysics, we addressed the core-collapse supernova problem to account for the apparently missing energy required to explain the observed powerful explosions. We assumed a small, massless scalar gravitational field, thus allowing General Relativity to be recovered in the weak-gravity asymptotic limit. The non-trivial effects coming from the coupling function in the presence of a high-density field were analyzed at the instant of neutron star formation. Our results show that the scalar gravitational field evolves from a cosmological value to a new equilibrium via a Higgs-like mechanism. Additionally, the calculations associated with the gravitational binding energy shift and relevant relaxation timescale are explicitly shown. The full theory space of the model was also investigated for positive values of the coupling parameter. We studied a mechanism to address the stalled shock issue in core-collapse scenarios, which involved the application of sufficiently large positive values to the coupling parameter. Our results show that pulsating neutron stars act like optical cavities in which resonant scalar waves are parametrically amplified. It implies that the surface of a neutron star acts like an anti-phase reflector, releasing traveling scalar gravitational waves similar to an optical laser. In cosmology, the same framework was applied to a generic Friedman-Robertson-Walker universe involving general metric coupling and scalar potential functions. In cosmology, the same framework was applied to a generic Friedman-Robertson-Walker universe involving general metric coupling and scalar potential functions. We developed a mechanism which allowed the scalar field to be dynamically trapped, thus generating a potential capable of driving primordial inflation. Our results show that a trapped scalar field produces non-trivial dynamical consequences when applied to standard cosmology. Additionally, our analytic solutions for the generic inflationary behaviour, produce acceptable duration and e-foldings, thus recovering the Hubble parameter which is consistent with the present-day value. A feature of our cosmological model is that the universe can undergo several accelerating or decelerating phases, even though the scalar potential and metric coupling are monotonic functions overall. As this is important for the current dark energy problem, the quasi-static motion of the gravitational field induced by the scalar potential in the early universe, is investigated for a small value of the scalar field with normalized metric at the present time. Our results show that a variable Lambda Cold Dark Matter universe emerges naturally from the quadratic model.

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8

Castro, Fábio Chibana de. "Tachyon Scalar Field Cosmology". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-17052017-063702/.

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In this work we test a cosmological model with an interaction between dark energy and dark matter, where a tachyon scalar field plays the role of dark energy. With that in mind, we developed a numerical code that solves the background equations and extracts the cosmological parameters and we compared the results of the interacting tachyon model with those of other dark energy candidates. Our results show that the model indeed explains the observational data and has interesting cosmological properties, but might face challenges when compared to other dark energy candidates.
Neste trabalho testamos um modelo cosmológico com uma interação entre energia escura e matéria escura, onde um campo escalar taquiônico desempenha o papel da energia escura. Para isso, desenvolvemos um código computacional que resolve as equações numericamente e vincula os parâmetros cosmológicos e, assim, comparamos os resultados do modelo taquiônico interagente com os de outros candidatos à energia escura. Nossas análises mostram que o modelo, de fato, consegue explicar os dados observacionais, além de possuir propriedades cosmológicas interessantes, mas apresenta dificuldades quando comparado a outros modelos de energia escura.

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9

Wilson, Toby. "Scalar fields and gravity". Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52355/.

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In this thesis we discuss scalar field theories, and their applications to gravity. We provide a summary of why there is interest in modifying Einstein’s General Relativity, and discuss why scalar fields make a good candidate for a modification to make. We demonstrate their effects on the dynamics of matter, and discuss the necessity of screening mechanisms in order for these scalar fields to not be ruled out by current observations. We present discussion on two screening mechanisms in particular, the Chameleon and Vainshtein mechanisms. We then present work that aims to study the soft behaviour of scattering amplitudes belonging to single scalar field theories. We generalise current techniques in the literature such that the study of a much wider set of theories is possible. We use this technique to perform a detailed study of a particular family of theories, a so called (1, 2) theory, and demonstrate that the DBI symmetry is the unique way to enhance the soft behaviour of the scattering amplitudes of this family. We also identify the special Galileon as the unique way to maximally enhance the soft behaviour within the (1, 2) class, and verify the validity of recursion techniques to calculate scattering amplitudes. We then move on to studying the Chameleon in more detail. We provide motivation for modifying its high energy behaviour by studying the ‘surfer solution’, and use this to propose the DBI-Chameleon. We demonstrate that this theory avoids the problems the Chameleon suffers in the early Universe and forms a good effective field theory in this regime. Finally we present a UV complete theory describing a massive Galileon, and study its dynamics to verify if it exhibits Vainshtein screening. Theories with Vainshtein screening are usually unable to be UV completed in a Wilsonian way. We present our preliminary findings which suggest screening is possible for at least some parameter values.

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10

Yayla, Oguz. "Scalar Multiplication On Elliptic Curves". Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607753/index.pdf.

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Elliptic curve cryptography has gained much popularity in the past decade and has been challenging the dominant RSA/DSA systems today. This is mainly due to elliptic curves offer cryptographic systems with higher speed, less memory and smaller key sizes than older ones. Among the various arithmetic operations required in implementing public key cryptographic algorithms based on elliptic curves, the elliptic curve scalar multiplication has probably received the maximum attention from the research community in the past a few years. Many methods for efficient and secure implementation of scalar multiplication have been proposed by many researchers. In this thesis, many scalar multiplication methods are studied in terms of their mathematical, computational and implementational points.

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11

Andersson, Mattias. "Scalar fields on star graphs". Thesis, Karlstads universitet, Avdelningen för fysik och elektroteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-9139.

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A star graph consists of a vertex to which a set of edges are connected. Such an object can be used to, among other things, model the electromagnetic properties of quantum wires. A scalar field theory is constructed on the star graph and its properties are investigated. It turns out that there exist Kirchoff's rules for the conserved charges in the system leading to restrictions of the possible type of boundary conditions at the vertex. Scale invariant boundary conditions are investigated in detail.
En stjärngraf består av en nod på vilken vilken ett antal kanter är anslutna. Ett sådant objekt kan bland annat användas till att modellera de elektromagnetiska egenskaperna hos kvanttrådar. En skalärfältsteori konstrueras på stjärngrafen och dess egenskaper undersöks. Det visar sig att det exisisterar en typ av Kirchoffs lagar för de konserverade laddningarna i systemet. Detta leder till restriktioner på vilka randvillkor som är möjliga vid noden. Skalinvarianta randvillkor undersöks i detalj.

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12

Grenier, Patrick. "Scalar fields generating contemporary inflation". Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80283.

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The evidence for an accelerating expansion of our Universe at the present epoch have led us to look for an energy component which could generate it. That may consist in quintessence in the form of a system of scalar fields {φa} rolling down a potential V({φ a}). This master's thesis presents the equations relevant to the cosmological evolution of such a system, along with the different conditions required for a viable cosmology. Also, via the exploration of two distinct models, two fundamental problems of quintessence theory are outlined. The impossibility of escaping the fine-tuning of initial conditions is first presented in link to the Liouville's theorem, and second the difficulty of avoiding the coincidence of the recent rise of quintessence even in the presence of attractors is shown.

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13

Distelhoff, Markus Friedrich Wilhelm. "Scalar mixing in stirred tanks". Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265206.

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14

Green, T. C. "Scalar controlled induction motor drives". Thesis, Heriot-Watt University, 1990. http://hdl.handle.net/10399/892.

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15

Malquarti, MichaeÌˆl. "Scalar fields and cosmic acceleration". Thesis, University of Sussex, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404774.

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16

Wands, David Graham. "Cosmology of scalar-tensor gravity". Thesis, University of Sussex, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335537.

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17

O'Gorman, Paul Ambrose Pullin Dale Ian. "Theory and simulation of passive scalar mixing in the presence of a mean scalar gradient /". Diss., Pasadena, Calif. : California Institute of Technology, 2004. http://resolver.caltech.edu/CaltechETD:etd-05272004-150652.

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18

Du, Hang y harrydu519@yahoo com au. "L.I.F.E long-scape". RMIT University. Architecture and Design, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091105.123653.

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What was once begun as research called LIFE has become the key component of my master's project. The meaning of LIFE has been redefined by a new landscape language. Living, infrastructure, traffic, shopping and eating identify the most common scenarios that are an intrinsic part of our daily lives. These are not exempt from the problems and difficulties characteristic of large cities like Shanghai. Landscape no longer focuses only on building parks or squares. In my project it has its own definition that informs about how to create a sustainable space not only for public use but also for private use. The research into the different ways people live has assisted me in identifying the Longtang morphology -a living system that was very popular and successful in downtown Shanghai in the 30's. Longtang is a fast-disappearing architecture due to the urban expansion in older Shanghai. Nowadays people's living conditions have improved. The buildings are new and mostly high-rise, without the unique Longtang style- easy eating and shopping ¨C in the past and without the good neighborhood relationships and useful public space. However, Longtang's living style to some extent surpasses the modern high-rise living structure. This research acknowledges the success of LIFE as a balanced schema in Longtang. The space in a traditional Longtang is neither public nor private. Longtang residents concede and build on its spatial negotiations, as private space is very restricted. Transferring private space into public space is one of the most important rules people learn while living in the Longtang. And my research question concerning how Longtang urban morphology can be used as a tool in the development of Shanghai becomes my key point in studying the Longtang structure, especially the changeability of the Longtang space. The research also identified a need for public space in various scales. The provision of this space is not easy as Shanghai is a highly dense area. My project proposes the use of public space as private-testing the strategy at different scales.

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19

Baxter, Alasdair Duncan. "The utilisation of scampi waste with special reference to properties of chitosan". Thesis, University of Lincoln, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276132.

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20

Lepore, Jason. "Experiments on passive scalar mixing in turbulent flows with different velocity- and scalar-field boundary conditions". Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119387.

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An experimental investigation of the influence of the large-scale features of turbulent flows on the mixing of a passive scalar therein is presented. Given the direct relationship between the large scales of turbulent flows and the geometrical configuration of the flow, two distinct sets of experiments are conducted in which the dependence of the scalar mixing on the (i) scalar- and (ii) velocity-field boundary conditions is studied. The first set of experiments is conducted in the plane wake downstream of a circular cylinder. To vary the scalar-field boundary conditions, while maintaining a hydrodynamically identical flow field, two different heat injection mechanisms are employed. First, a heating element is embedded within the cylinder that generates the hydrodynamic wake. When the element is energized, the wake is therefore heated by means of a "heated cylinder." Second, an array of fine, Nichrome wires is installed downstream of the cylinder. This configuration, known as a "mandoline," has been demonstrated to have a negligible influence on the velocity field, due to the small diameter of the wires. Using this apparatus, multiple velocity and passive-scalar statistics are examined. The measurements suggest that certain small-scale statistics may be contaminated by the large-scale features of the scalar field. Consequently, it is of interest to determine why such statistics exhibit these dependencies. In particular, the passive scalar structure functions, and their inertial-convective-range scaling exponents, along with the mixed velocity-temperature structure functions and the (non-centered) autocorrelations of the dissipation rate of scalar variance are employed to obtain quantitative estimates of the internal intermittency of the passive scalar field. It is revealed that the high-order passive scalar structure function scaling exponents display a significant difference when comparing the results generated using different heat injection mechanisms. Upon examination of the kurtosis structure functions of the temperature difference, the present work suggests that passive scalar structure function scaling exponents exhibit a dependence on the scalar-field boundary conditions due to the finite (and different) Péclet numbers of the flows under consideration — an effect that is significantly less prominent in the measurements of the mixed velocity-temperature structure functions and the (non-centered) autocorrelations of the dissipation rate of scalar variance. The second set of experiments consists of a study of the scalar field downstream of a concentrated line source within a fully-developed, high-aspect-ratio channel flow. However, unlike previous dispersion measurements employing concentrated sources, the current research employs a line source oriented in the direction of the inhomogeneity of the velocity field. Consequently, the resulting wake downstream of the line source is statistically three-dimensional. In such an arrangement, the velocity field at each wall-normal position is different, since the velocity field in the current configuration is solely a function of the wall-normal distance. The resultant mixing is studied using a variety of statistics, including the mean and root-mean-square temperature distributions, probability density functions of the temperature fluctuations, as well as the (turbulent) intensity of the scalar fluctuations. These results are contrasted with prior transverse dispersion measurements in which the scalar dispersion remains statistically two-dimensional, in an attempt to elucidate the effect of the velocity-field boundary conditions. The findings suggest that both the mean flow shear and turbulence intensity of the velocity field play an important role in determining the mixedness of the scalar field.
Une étude expérimentale de l'effet des caractéristiques à grandes-échelles des écoulements turbulents sur le mélange d'un scalaire passif y est présentée. Étant donné la relation directe entre les grandes échelles des écoulements turbulents et la configuration géométrique de l'écoulement, deux ensembles d'expériences distincts sont menés dans lesquels la dépendance du mélange d'un scalaire sur les conditions limites du (i) champ scalaire et (ii) champ de vitesse est étudiée. Le premier ensemble d'expériences est réalisé dans le sillage d'un cylindre circulaire. Pour varier les conditions limites du champ scalaire, tout en gardant le même écoulement hydrodynamique, deux mécanismes d'injection de chaleur différents sont utilisés. Premièrement, un élément chauffant est incorporé dans le cylindre qui génère le sillage hydrodynamique. Lorsque l'élément est mis sous tension, le sillage est donc chauffé au moyen d'un « cylindre chauffé ». Deuxièmement, un ensemble de fils fins est installé en aval du cylindre. Cette configuration, connue sous le nom de « mandoline, » s'est avérée d'avoir une influence négligeable sur le champ de vitesse, en raison du faible diamètre des fils. Par conséquent, l'une des deux configurations peut être utilisée pour chauffer le sillage, sans modifier le champ de vitesse, et de nombreuses statistiques du champ scalaire et du champ de vitesse sont examinées. En particulier, les fonctions de structure du champ scalaire (et leurs exposants d'échelle), ainsi que les fonctions de structure mixte vitesse-température et les autocorrélations (non-centrées) du taux de dissipation de la variance scalaire, sont utilisées pour obtenir des estimations quantitatives de l'intermittence interne du champ scalaire. Il est conclu que les exposants d'échelle des fonctions de structure du champ scalaire passif présentent une différence importante lorsque l'on compare les résultats obtenus en utilisant de différents mécanismes d'injection de chaleur. Lorsque l'on examine les fonctions de structure du coefficient d'aplatissement de la différence de température, ce mémoire suggère que les exposants d'échelle des fonctions de structure démontrent une dépendance aux conditions limites du champ scalaire en raison des nombres de Péclet finis (et différents) des écoulements étudiés — un effet qui est nettement moins important dans les fonctions de structure mixte vitesse-température et les autocorrélations du taux de dissipation de la variance scalaire.Le deuxième ensemble d'expériences consiste d'une étude du champ scalaire en aval d'une source concentrée linéaire dans un écoulement de canal pleinement développé, ayant un rapport hauteur-largeur élevé. Contrairement à des mesures de dispersion précédentes utilisant des sources concentrées, ce travail emploie une source linéaire orientée dans la direction de l'inhomogénéité du champ de vitesse. Par conséquent, le panache thermique créé par la source linéaire est (statistiquement) tridimensionnel. Dans une tel configuration, le champ de vitesse à chaque distance du mur est différent, puisque le champ de vitesse dans la configuration actuelle est uniquement une fonction de la distance du mur. Le mélange du scalaire passif est étudié en utilisant une variété de statistiques, incluant la moyenne et la moyenne quadratique du champ de température, des fonctions de densité de probabilité des fluctuations de température, ainsi que l'intensité (turbulent) des fluctuations scalaires. Ces résultats (i) exposent les différences entre ces mésures et celles de dispersion transverse, dans lesquelles la dispersion du scalaire reste statistiquement bidimensionel, et (ii) facilitent l'élucidation des effets des conditions limites du champ de vitesse sur le mélange d'un scalaire passif. Les résultats suggèrent que le cisaillement de l'écoulement moyen et l'intensité turbulent du champ de vitesse jouent un rôle important dans la détermination du niveau de mélange du champ scalaire.

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21

Anteau, Michael J. "Ecology of lesser scaup and amphipods in the upper-Midwest scope and mechanisms of the spring condition hypothesis and implications for migration habitat conservation /". Connect to this title online, 2006. http://etd.lsu.edu/docs/available/etd-01242006-093828/.

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22

Juárez, Aubry Benito Alberto. "Scalar Field Coupling to BF Gravity". Thesis, Universidad de las Américas Puebla, 2011. http://catarina.udlap.mx/u_dl_a/tales/documentos/lfa/juarez_a_ba/.

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We perform the coupling of a scalar field to the action principle of the BF type introduced by Capovilla, Montesinos, Prieto, and Rojas; known as CMPR, which describes general relativity and includes the Immirzi parameter. This coupling is naturally also valid in the framework of the modified CMPR action with cosmological constant developed by Montesinos and Velázquez..

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23

Bos, Wouter. "Passive scalar mixing in turbulent flow". Phd thesis, Ecole Centrale de Lyon, 2005. http://tel.archives-ouvertes.fr/tel-00199364.

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Le mélange d'un scalaire passif par un écoulement turbulent est étudié. D'abord, la simulation numérique directe (DNS), la simulation des grandes échelles (LES) et des arguments dimensionnels sont employés pour étudier le spectre du flux de scalaire dans une turbulence isotrope avec un gradient moyen uniforme de scalaire. Une loi d'échelle est dérivée. Cette loi conduit à des pentes du spectre variant entre -5/3 et -7/3 en zone inertielle. De premiers résultats de LES plaident en faveur d'un comportement en K^-2. Ensuite, en utilisant une fermeture en deux points (EDQNM), nous montrons qu'aux nombres de Reynolds très élevés, le spectre de flux de scalaire dans la zone intertielle se comporte en K^-7/3. Ce résultat est en accord avec l'analyse dimensionnelle classique de Lumley (1967). Aux nombres de Reynolds correspondant aux expériences de laboratoire, la fermeture conduit à des spectres plus près de K^-2. Nous montrons ensuite que le comportement en K^-2 trouvé en LES est induit par le forçage à grande échelle. La fermeture est alors appliquée au cas des écoulements homogènes cisaillés et les spectres du flux de scalaire longitudinal et transverse sont étudiés. Le spectre du flux longitudinal est trouvé proportionnelle à K^-23/9. Ce résultat est en accord avec l'expérience mais est en désaccord avec l'analyse dimensionnelle classique. Finalement, nous montrons que le lien entre la dispersion de particules et le mélange d'un scalaire permet de formuler une fermeture en deux points et un temps qui ne nécessite l'introduction d'aucune constante dans le modèle.

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24

Ramamurthy, Arun. "Towards scalar synchronization in SIMT architectures". Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37732.

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An important class of compute accelerators are graphics processing units (GPUs). Popular programming models for non-graphics computation on GPUs, such as CUDA and OpenCL, provide an abstraction of many parallel scalar threads. Contemporary GPU hardware groups 32 to 64 scalar threads as a single warp or wavefront and executes this group of scalar threads in lockstep. The inherent mismatch between scalar programming model and vector hardware creates a challenge when developing applications that employ synchronization on the GPU. This challenge arises from the use of a hardware stack to manage control flow divergence among scalar threads. This thesis explains the porting of the Apriori benchmark to a GPU which led to the research on synchronization in SIMT hardware. It then proposes instruction set and hardware changes that simplify the implementation of mutual exclusion when porting multiple-instruction, multiple data (MIMD) programs with synchronization to accelerators employing single-instruction, multiple thread (SIMT) hardware. These instructions when compared with more complex software only solutions, achieve similar performance. This thesis also implements and evaluates queue based mutual exclusion on SIMT hardware.

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25

Lavertu, Robert A. "Scalar dispersion in turbulent channel flow". Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79243.

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Experimental results of scalar dispersion from a concentrated source in an inhomogeneous turbulent flow field are presented in this thesis.
The flow field is fully developed channel flow---one of the simplest inhomogeneous turbulent flows. A fine line source is used to inject the scalar (temperature). The temperature injection does not affect the flow field, hence it is passive. The line source is in the spanwise (z) direction of the channel, and is located at transverse (i.e., wall-normal) locations: y/h = 0.067, 0.17, and 1.0 (where h is the channel half-width). Measurements of the resultant thermal plume for each source location are taken for two Reynolds numbers: 10400 and 22800 (where Re = Uch/nu: U c is the centerline velocity and nu is the kinematic viscosity). Hot-wire anemometry and cold-wire thermometry are used to acquire velocity and temperature data, respectively.
It is shown that the downstream decay of the mean temperature rise is less than that of isotropic grid-generated turbulence and homogenous turbulent shear flow. The peak RMS temperature fluctuation also decays at a slower rate. For the near-wall source locations, the peak of the transverse RMS temperature profile drifts toward the channel centerline with increasing downstream distance from the source. Also, for the near-wall source locations, the scalar PDF is quasi-Gaussian, indicating improved mixing in that region. As the plume is traversed toward the centerline, the PDF evolves into a very positively skewed shape.
An extensive database of the thermal plume is compiled, which consists of the mean, RMS, and skewness profiles of the temperature field, PDFs of the temperature field, and temperature-velocity correlations. This database can be used to test numerical and/or theoretical models, highlighting their strengths and weaknesses.

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26

Díaz, Calzadilla Pablo. "Scalar stars and effective field theory". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23167/.

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The axion is one of the favored candidates to form the cold dark matter in the universe. This pseudo-scalar field may form compact objects called axion stars, whose physics is well captured by means of non-relativistic effective field theory coupled to Newtonian gravity. The interplay between gradient energy, self-interactions and gravity gives rise to both dilute and dense axion stars. While the existence of the dilute axion stars is well established, the situation is more complicated in the case of the so-called dense axion stars, an extra physically stable solution of the system of differential equations describing the dynamics of the axion field in the regime where self-interactions play an important role. The existence of the dense axion stars has not been settled in the literature. In this thesis, we discuss first the appropriate non-relativistic formalism for the study of these clumps by means of the various non-relativistic reductions found in the literature. We analyze the stability, for different sizes and number of particles, of these objects considering quartic self-interaction potentials. This allows us to corroborate the results for these cases already presented by other authors. We also go beyond the simplest case, by analyzing more complicated potentials describing with higher precision the axion self-interactions. By employing the correct non-relativistic axion effective field theory we show that the dense branch is an artefact of the non-relativistic reduction procedure.

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27

Burvall, Anna. "Axicon imaging by scalar diffraction theory". Doctoral thesis, KTH, Microelectronics and Information Technology, IMIT, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3736.

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Axicons are optical elements that produce Bessel beams,i.e., long and narrow focal lines along the optical axis. Thenarrow focus makes them useful ine.g. alignment, harmonicgeneration, and atom trapping, and they are also used toincrease the longitudinal range of applications such astriangulation, light sectioning, and optical coherencetomography. In this thesis, axicons are designed andcharacterized for different kinds of illumination, using thestationary-phase and the communication-modes methods.

The inverse problem of axicon design for partially coherentlight is addressed. A design relation, applicable toSchell-model sources, is derived from the Fresnel diffractionintegral, simplified by the method of stationary phase. Thisapproach both clarifies the old design method for coherentlight, which was derived using energy conservation in raybundles, and extends it to the domain of partial coherence. Thedesign rule applies to light from such multimode emitters aslight-emitting diodes, excimer lasers and some laser diodes,which can be represented as Gaussian Schell-model sources.

Characterization of axicons in coherent, obliqueillumination is performed using the method of stationary phase.It is shown that in inclined illumination the focal shapechanges from the narrow Bessel distribution to a broadasteroid-shaped focus. It is proven that an axicon ofelliptical shape will compensate for this deformation. Theseresults, which are all confirmed both numerically andexperimentally, open possibilities for using axicons inscanning optical systems to increase resolution and depthrange.

Axicons are normally manufactured as refractive cones or ascircular diffractive gratings. They can also be constructedfrom ordinary spherical surfaces, using the sphericalaberration to create the long focal line. In this dissertation,a simple lens axicon consisting of a cemented doublet isdesigned, manufactured, and tested. The advantage of the lensaxicon is that it is easily manufactured.

The longitudinal resolution of the axicon varies. The methodof communication modes, earlier used for analysis ofinformation content for e.g. line or square apertures, isapplied to the axicon geometry and yields an expression for thelongitudinal resolution. The method, which is based on abi-orthogonal expansion of the Green function in the Fresneldiffraction integral, also gives the number of degrees offreedom, or the number of information channels available, forthe axicon geometry.

Keywords:axicons, diffractive optics, coherence,asymptotic methods, communication modes, information content,inverse problems

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28

Skarbø, Roger. "FPGA Implementation of a Video Scaler". Thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10187.

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Three algorithms for video scaling were developed and tested in software, for implementation on an FPGA. Two of the algorithms were implemented in a video scaler system. These two algorithms scale up with factors 1.25 and 1.875, which is used for scaling SD WIDE to HD resolution and SD WIDE to FullHD resolution, respectively. An algorithm with scaling factor 1.5, scaling HD to FullHD, was also discussed, but not implemented. The video scaler was tested with a verilog testbench provided by ARM. When passing the testbench, the video scaler system was loaded on an FPGA. Results from the FPGA were compared with the software algorithms and the simulation results from the testbench. The video scaler implemented on the FPGA produced predictable results. Even though a fully functional video scaler was made, there were not time left to create the necessary software drivers and application software that would be needed to run the video scaler in real time with live video output. So a comparison of the output from the implemented algorithms is performed with common scaling algorithms used in video scalers, such as bilinear interpolation and bicubic interpolation. This thesis also deal with graphics scaling. Some well-known algorithms for graphic scaling were written in software, including a self-made algorithm to suit hardware. These algorithms were not implemented in hardware, but comparison of the results are performed.

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29

Dick, Frank Albert. "Scalar field theories of nucleon interactions". Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-042507-084002/.

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Dissertation (Ph.D.) -- Worcester Polytechnic Institute.
Keywords: ladder approximation; inelastic process; Bethe-Salpeter; BSE; nucleon; scalar field; pion. Includes bibliographical references (p.161-163).

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30

Lin, Zhi McLaughlin Richard M. "Passive scalar intermittency in random flows". Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,1143.

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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2007.
Title from electronic title page (viewed Mar. 27, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Mathematics." Discipline: Mathematics; Department/School: Mathematics.

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31

Foster, Scott. "Singularity structure of scalar field cosmologies /". Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phf757.pdf.

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32

Hawkins, Rachael Mary. "Scalar field Braneworld and inflationary cosmologies". Thesis, Queen Mary, University of London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414462.

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33

Thorne, Robert S. "Renormalizability of effective scalar field theory". Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358742.

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34

Stephanov, Mikhail Alexeevich. "Scalar-fermion theories on the lattice". Thesis, University of Oxford, 1994. http://ora.ox.ac.uk/objects/uuid:555a30de-2df9-4d39-b2dc-1974398911f7.

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We study scalar-fermion models with Yukawa interaction on a space-time lat- tice. Such models can describe the Higgs sector of the Standard Model in the case when the Higgs particle is very heavy (few hundred GeV) and there are very heavy fermions whose masses are due to their Yukawa interactions with the Higgs field. We study a realistic model with four component scalar field as well as simplified models with one and two component scalar fields. We use a mean field approximation to calculate equations for critical lines in the large d (dimension of space-time) limit. These lines are in very good agreement with available Monte Carlo data for the models at d = 4. We calculate fermion correlation functions in the mean field and large d approximations to study properties of different phases in the lattice models. We find two distinct phases with vanishing expectation values of the scalar field. One (at small Yukawa coupling Y) contains massless fermions, while in the other (at large F) the fermions have masses larger than the scale given by the inverse lattice spacing. We find that in the latter phase fermions can form bosonic bound states. These states show up as poles in a four-fermion correlator. We discuss pos- sible continuum limits in the lattice scalar-fermion models. In particular, we show that a theory defined near the critical line separating the disordered phase from the phase with antiferromagnetic order is not unitary.

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35

Filippopoulos, Pavlos. "Reference memory in human scaler timing". Thesis, Keele University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510708.

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This thesis explored the role of reference memory in human scalar timing. Chapters 3 and 4 examined if there is a distinction between reference memory and working memory. Using a combination of normal temporal generalization and pseudoepisodic temporal generalization conditions, the same physical durations (comparisons and standards) were asked to be compared by participants and judge for their equality (Chapter 3). Even though conditions consisted of the same comparison and standard durations participants showed difference in behaviour between the two tasks: that is it appeared that in normal temporal generalization they appeared to be more conservative in responding YES to whether a comparison was the same as a standard. Computer modelling supported these findings (Chapter 4). Chapter 5 examined a simple possible interference task. Participants were asked to provide judgements in a test block after being exposed to interfered blocks towards different standard durations (short, long or same interference) with the use of shorter or longer standards and comparisons. An interference effect was discovered and supported by computer modelling that raised logical questions towards the stability of reference memory, not only through interference from different standards but from comparison durations as well. The instability of reference memory due to bias manipulation was examined in Chapters 6 and 7. PartiCipants were biased by the use of shorter or longer comparisons (bias sequences) in order to misjudge the standard as being shorter or longer in a test sequence after they have completed a short or long bias sequence. Chapter 6 also explored the biasing effect with the use of post-response feedback. The effect was also supported by computer modelling in Chapter 7. The thesis overall suggested a clear distinction between reference and working memory and provided evidence supporting the instability of reference memory through interference (standard manipulation) and bias (comparison manipulation).

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36

Da, Silva Caroline Dos Santos. "Cosmic strings and scalar tensor gravity". Thesis, Durham University, 1999. http://etheses.dur.ac.uk/4577/.

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This thesis is concerned with the study of cosmic strings. We studied the values for the Higgs mass and string coupling for which the gravitational effect of an infinite cosmic string in the context of the Einstein theory is not only locally but also globally weak. We conclude this happens for strings formed at scales less or equal to the Planck one with Higgs mass being less or equal to the boson vectorial mass. Then we examined the metric of an isolated self-gravitating abelian-Higgs vortex in dilatonic gravity for arbitrary coupling of the vortex fields to the dilaton. We looked for solutions in both massless and massive dilaton gravity. We compared our results to existing metrics for strings in Einstein and .Jordan-Brans-Dicke theories. We explored the generalisation of Bogomolnyi arguments for our vortices and commented on the effects on test particles. We then included the presence of an axion field and examined the metric of an isolated self-gravitating axionic-dilatonic string. Finally we studied dilatonic strings through black hole solutions in string theory. We concluded that the horizon of non-extreme charged black holes supports the long-range fields of the Nielsen-Olesen string that can be considered as black hole hair and whose gravitational effect is in general the production of a conical deficit into the metric of the black hole background. We also concluded that the effect of the dilaton on the horizon of these black holes is to generate an additional charge.

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37

Hawley, Scott Hearne. "Scalar analogues of compact astrophysical systems /". Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.

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38

Puliçe, Beyhan Demir Durmuş Ali. "Spacetime Compactification Induced By Scalar Fields/". [s.l.]: [s.n.], 2006. http://library.iyte.edu.tr/tezlerengelli/master/fizik/T000606.pdf.

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39

Gleeson, James P. Saffman P. G. "Randon advection of a passive scalar /". Diss., Pasadena, Calif. : California Institute of Technology, 1999. http://resolver.caltech.edu/CaltechETD:etd-02062008-095449.

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40

Marchais, Edouard. "Infrared properties of scalar field theories". Thesis, University of Sussex, 2013. http://sro.sussex.ac.uk/id/eprint/45244/.

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Phase transitions and critical phenomena are of central importance in quantum field theory and statistical physics. We investigate the low energy properties of O(N) symmetric scalar field theories using functional renormalisation group methods for all N. This modern formulation of Wilson's renormalisation group allows a continuous interpolation between short and long distance physics without resorting to a weak coupling expansion. To leading order in the derivative expansion, we study the phase transition and the approach to convexity in the deep infrared limit. In the limit of infinite N, the fluctuations of the Goldstone modes dominate allowing for a complete analytical discussion of the effective potential. For finite N, the radial fluctuations become important and we resort to systematic series expansions. In both cases a systematic and thorough analysis of the diverse fixed point solutions is carried out. This leads to a comprehensive picture of the scaling potential for a large number of universality classes. We also study the dependence of our results on the regularisation scheme. Finally, we establish that the infrared completion of the effective potential in the broken phase is driven by a fixed point that leads to the flattening of the non-convex part of the potential.

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41

Palma, Gonzalo Alejandro. "Bulk scalar fields in braneworld models". Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614285.

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42

Bhattacharya, Arindam. "Gradient Dependent Reconstruction from Scalar Data". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1449181983.

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43

Wang, Hua. "Colour image representation by scalar variables". Thesis, Loughborough University, 1992. https://dspace.lboro.ac.uk/2134/10477.

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A number of studies have shown that it is possible to use a colour codebook, which has a limited number of colours (typically 100-200), to replace the colour gamut and obtain a good quality reconstructed colour image. Thus colour images can be displayed on less expensive devices retaining high quality and can be stored in less space. However, a colour codebook is normally randomly arranged and the coded image, which is referred to as the index image, has no structure. This prevents the use of this kind of colour image representation in any further image processing. The objective of the research described in this thesis is to explore the possibility of making the index image meaningful, that is, the index image can retain the structure existing in the original full colour image, such as correlation and edges. In this way, a three band colour image represented by colour vectors can be transfomled into a one band index image represented by scalar variables. To achieve the scalar representation of colour images, the colour codebook must be ordered to satisfy the following two conditions: (I) codewords representing similar colours must be close together in the code book and (2) close code words in the codebook must represent similar colours. Some effective methods are proposed for ordering the colour codebook. First, several grouping strategies are suggested for grouping the code words representing similar colours together. Second, an ordering function is designed, which gives a quantity. measurement of the satisfaction of the two conditions of an ordered codebook. The code book ordering is then iteratively refined by the ordering function. Finally, techniques, such as artificial codeword insertion, are developed to refine the code book ordering further. A number of algorithms for colour codebook ordering have been tried to retain as much structure in the index image as possible. The efficiency of the algorithms for ordering a colour codebook has been tested by applying some image processing techniques to the index image. A VQ/DCT colour image coding scheme has been developed to test the possibility of compressing and decompressing the index image. Edge detection is applied to the index image to test how well the edges existing in the original colour image can be retained in the index image. Experiments demonstrate that the index image can retain a lot of structure existing in the original colour image if the codebook is ordered by an appreciate ordering algorithm, such as the PNNbased/ ordering function method together with artificial codeword insertion. Then further image processing techniques, such as image compression and edge detection, can be applied to the index image. In this way, colour image processing can be realized by index image processing in the same way as monochrome image processing. In this sense, a three-band colour image represented by colour vectors is transformed into a single band index image represented by scalar variables.

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44

Domenech, Fuertes Guillem. "Inflationary Cosmology in Scalar-Tensor Theories". Kyoto University, 2017. http://hdl.handle.net/2433/227579.

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45

Raza, Aleksis. "Scalar curvature and multiplicity-free actions". Thesis, Imperial College London, 2006. http://hdl.handle.net/10044/1/1264.

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This thesis comprises of three main results. First, we use Guillemin-Abreu theory from KÃƒ?Ã‚Â¤hler toric geometry to derive a formula for the scalar curvature of SU(n)-invariant KÃƒ?Ã‚Â¤hler metrics on Cn n f0g or, equivalently, spaces of the form S2nÃƒ?Ã‚Â¡1 Ãƒ?Ã‚Â£ (0,Ãƒ?Ã‚Â¥). Second, we use the aforementioned formula to describe a U(n)-invariant, scalar-flat, KÃƒ?Ã‚Â¤hler metric on the blow-up bCn of Cn at the origin in symplectic coordinates. This metric is the generalization of the well-known Burns metric on bC2. Third, we use an equivariant version of an Ãƒ?Ã‚?infinite dimensional moment map frameworkÃƒ?Ã‚? to derive a formula for the scalar curvature of SU(n)-invariant, KÃƒ?Ã‚Â¤hler metrics on the multiplicity-free SU(n)-space Xn of the form SU(n) Ãƒ?Ã‚Â£ U where U is a certain open connected subset of the Lie algebra of a Cartan torus in SU(n) i.e. RnÃƒ?Ã‚Â¡1.

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46

Westmoreland, Shawn. "Energy conditions and scalar field cosmology". Kansas State University, 2013. http://hdl.handle.net/2097/15811.

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Master of Science
Department of Physics
Bharat Ratra
In this report, we discuss the four standard energy conditions of General Relativity (null, weak, dominant, and strong) and investigate their cosmological consequences. We note that these energy conditions can be compatible with cosmic acceleration provided that a repulsive cosmological constant exists and the acceleration stays within certain bounds. Scalar fields and dark energy, and their relationships to the energy conditions, are also discussed. Special attention is paid to the 1988 Ratra-Peebles scalar field model, which is notable in that it provides a physical self-consistent framework for the phenomenology of dark energy. Appendix B, which is part of joint-research with Anatoly Pavlov, Khaled Saaidi, and Bharat Ratra, reports on the existence of the Ratra-Peebles scalar field tracker solution in a curvature-dominated universe, and discusses the problem of investigating the evolution of long-wavelength inhomogeneities in this solution while taking into account the gravitational back-reaction (in the linear perturbative approximation).

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47

Thornton, Andrew M. "Studies of lattice fermion-scalar interactions". Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/14539.

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48

Schultz, Anne-Catrin. "Der Schichtungsprozess im Werk von Carlo Scarpa eine Untersuchung der Hintergründe von Entwurfsmethodik und Kompositionstrategie Carlo Scarpa's /". [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=958856389.

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49

馮穎川 y Wing-chuen Edmond Fung. "Maritime Museum Park-scape". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31985178.

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Fung, Wing-chuen Edmond. "Maritime Museum Park-scape". Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25945488.

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Tesis sobre el tema "SCaMPR"

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