Dissertations / Theses on the topic 'Buffet'

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1

Findlay, David Bruce. "A numerical study of aircraft empennage buffet." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/10926.

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2

Zan, Steven James. "An investigation of low-speed wing buffet." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358845.

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3

Bogdanski, Steffen [Verfasser]. "Numerische Untersuchungen zum stoßinduzierten Buffet / Steffen Bogdanski." München : Verlag Dr. Hut, 2014. http://d-nb.info/1060587645/34.

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4

Mayer, Rouven [Verfasser]. "Buffet Control by Shock Control Bumps / Rouven Mayer." München : Verlag Dr. Hut, 2019. http://d-nb.info/1188516345/34.

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5

Hawley, Charles William. "Broke at the buffet : food insecurity in America." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1676.

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6

Giannelis, Nicholas Frank. "Transonic Shock Buffet in Rigid and Aeroelastic Systems." Thesis, The University of Sydney, 2019. https://hdl.handle.net/2123/21515.

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For limited flight conditions in the transonic regime, self-sustained shock oscillations may develop. This transonic shock buffet phenomenon limits the flight envelope and is detrimental to both aircraft handling qualities and structural integrity. While substantial research has been devoted to this transonic instability, an understanding of how buffet evolves through the flight envelope and how this affects the aeroelastic response has remained elusive. This work aims to address these questions. URANS simulations are performed on three wing sections across a range of freestream conditions. Evaluation of the buffet boundaries highlights differences between thick and thin profiles. The buffet response is found to be particularly sensitive to changes in Mach number and incidence. High-incidence conditions on thick profiles yield atypical motions in which the shock dissipates during its upstream excursion. A bimodal cycle is found at moderate incidence on the thin profile, where the flow alternates between leading-edge stall and classical buffet motion. Modal decomposition of the flow reveals these motions stem from increasingly prevalent fluidic modes associated with shear layer instabilities. Aeroelastic simulations highlight distinct response characteristics and a greater sensitivity to the structural configuration for the thin profile. Synchronisation between the aerodynamic and structural responses is found in pitch, heave and pitch-heave simulations for both profiles. Lock-in to the pitch mode occurs at pitch frequencies above the buffet, and to the heave mode for heave frequencies below. This behaviour varies with the mass and damping ratio and CG translation. Further, a relationship between lock-in and nontypical transonic LCOs is identified. Two data-driven methods for stability analysis are also developed to classify the modal interactions of the aeroelastic response from limited data.
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Woods, M. I. "An investigation of buffet over low-observable planforms." Thesis, University of Bath, 1999. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285317.

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8

Kelly, Edward. "Bend it like Buffet - The application of Torbets Leadership." Thesis, Lancaster University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525162.

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9

Merrill, Megan J. "Food selection behaviors of children in a buffet setting /." View online, 2009. http://repository.eiu.edu/theses/docs/32211131559265.pdf.

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10

Hartmann, Axel [Verfasser]. "Experimental Analysis of Wave Propagation at Buffet Flows / Axel Hartmann." Aachen : Shaker, 2012. http://d-nb.info/106904623X/34.

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11

Hunt, David Leslie. "An investigation of supersonic buffet using a Large Eddy Simulation." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318735.

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12

El-Badawy, Ayman Aly. "Structural Identification and Buffet Alleviation of Twin-Tailed Fighter Aircraft." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/26764.

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We tackle the problem of identifying the structural dynamics of the twin tails of the F-15 fighter plane. The objective is to first investigate and identify the different possible attractors that coexist for the same operating parameters. Second is to develop a model that simulates the experimentally determined dynamics. Third is to suppress the high-amplitude vibrations of the tails due to either principal parametric or external excitations. To understand the dynamical characteristics of the twin-tails, the model is excited parametrically. For the same excitation amplitude and frequency, five different responses are observed depending on the initial conditions. The coexisting five responses are the result of the nonlinearities. After the experimental identification of the system, we develop a model to capture the dynamics realized in the experiment. We devise a nonlinear control law based on cubic velocity feedback to suppress the response of the model to a principal parametric excitation. The performance of the control law is studied by comparing the open- and closed-loop responses of the system. Furthermore, we conduct experiments to verify the theoretical analysis. The theoretical and experimental findings indicate that the control law not only leads to effective vibration suppression, but also to effective bifurcation control. We investigate the design of a neural-network-based adaptive control system for active vibration suppression of the model when subjected to a parametric excitation. First, an emulator neural network was trained to represent the structure and thus used to predict the future responses of the model. Second, a neurocontroller is developed to determine the necessary control action. The computer-simulation studies show great promise for artificial neural networks to control the model vibrations caused by parametric excitations. We investigate the use of four different control strategies to suppress high-amplitude responses of the F-15 fighter to a primary resonance excitation. The control strategies are linear velocity feedback, nonlinear velocity feedback, positive position feedback, and saturation-based control. For each case, we conduct bifurcation analyses for the open- and closed-loop responses of the system and investigate theoretically the performance of the different control strategies. We also calculate the instantaneous power requirements of each control law. The experimental results agree with the theoretical findings.
Ph. D.
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13

Tung, Wei-Chia. "A customer perception and satisfaction survey for a Chinese buffet." Online version, 2003. http://www.uwstout.edu/lib/thesis/2003/2003tungw.pdf.

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14

Greeven, Frank Grace Catherine. "Diseño de Balanced Scorecard en Buffet´s de Grupo CGC." Tesis, Universidad de Chile, 2008. http://repositorio.uchile.cl/handle/2250/101943.

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El objetivo principal de este estudio fue diseñar una herramienta de control de gestión, en particular un Balance Scorecard o Cuadro de Mando Integral en el restaurante Buffet’s perteneciente a Grupo CGC, con el fin de mejorar el control de gestión que se realiza actualmente. Entre las falencias que se identificaron en el sistema actual se encuentra el poco control y la inexistencia de indicadores financieros. En el estudio se partió utilizando la metodología de Rediseño de Procesos. Las etapas fueron las siguientes: definir el caso, investigando todos los departamentos y personas que participan en la planificación estratégica y control de la gestión, basado en la recopilación de la información; comprender la situación actual, a través de reuniones con el personal que trabaja en las distintas áreas involucradas, además de la revisión de los procesos en terreno; rediseñar, a través de entrevistas con diversos estamentos de la empresa. En la etapa de rediseño del proceso se decidió implementar un Balance Scorecard pues permite superar las limitaciones de la gestión basada sólo en información financiera y en indicadores de resultado, incorporando métricas asociadas a los clientes, proveedores, el personal, la tecnología y la innovación. Para el diseño se realizaron las siguientes actividades: análisis del entorno; definir y/o proponer mejoras de la misión, visión, análisis FODA, estrategia genérica, objetivos corporativos y objetivos de los centros de negocio; traducir la visión, estrategias y objetivos corporativos en forma de variables claves y de metas y estándares susceptibles de control; diseñar indicadores para la evaluación de la gestión; confeccionar el mapa estratégico; y, crear los planes estratégicos. En términos generales, los resultados obtenidos de la implementación del Balance Scorecard fueron: integración de la variable financiera a la planificación estratégica y el control de la gestión; mejora de los indicadores; mejora del proceso de toma de decisiones; acceso a la información de control en forma oportuna; y, disminución de los errores a lo largo del proceso de control. Como conclusión se encuentra que se realizaron mejoras en la misión y la visión. La estrategia que posee Buffet’s es de diferenciación por producto, donde el cliente elige el producto por su calidad, por su sabor. Algunos de los objetivos que estaban declarados en la empresa se mantuvieron, por otro lado, se crearon otros, especialmente del área financiera. Se identificaron dos temas estratégicos en el mapa, estos fueron: aumento de ventas y la disminución de costos. La mayoría de los objetivos, sin embargo, están orientados al aumento de las ventas, algo que se ha visto mermado en el último año, por el surgimiento de competencia. Se pretende lograr, como objetivo ligado a las ventas, un aumento del 5% semestral. Como recomendación se sugiere especial cuidado en la implementación de este diseño, especialmente con el recurso humano involucrado, de manera de lograr su apoyo e involucramiento.
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15

Lapponi, André. "Bloomberg UPT 2019. Parte 6 de 12. Análisis fundamental de compañías con Bloomberg." Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/628246.

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La Universidad Peruana de Ciencias Aplicadas (UPC) fue sede de la segunda edición del “University Premium Training” organizada por Bloomberg, empresa líder en información financiera y económica a nivel mundial. / El evento, que fue realizado los días 5, 6 y 7 de noviembre en el campus San Isidro, tuvo como objetivo poder reforzar las competencias de los docentes de diversas universidades de Lima que emplean Bloomberg como una herramienta didáctica para la educación y planificación financiera. Esta compañía brinda herramientas de software financiero, como análisis, plataformas de comercio capital y servicios de datos para las empresas quienes deseen consultar información bursátil y financiera en tiempo real. / Además, se contó con la participación de expertos que emplean la herramienta como apoyo para la toma de decisión financiero: Lizzette Lara; especialista en riesgos y derivados, André Lapponi; especialista Senior en Portafolio y Análisis técnico, Pedro Cortejo, CEO-Founder de Decision Capital, entre otros.
Se explica el análisis de las últimas crisis en USA, la estrategia de Warren Buffet, la selección de acciones y portafolio. Ponente: André Lapponi, especialista senior en portafolios y análisis técnico – Bloomberg.
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16

Black, Christopher Lee Carleton University Dissertation Engineering Aerospace. "CF-18 tail buffet prediction based on rigid model pressure data." Ottawa, 1993.

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17

Lemos, Melina Mirley da Silva. "Avaliação da qualidade microbiológica do ar em cozinhas e zonas de buffet." Master's thesis, Escola Superior de Hotelaria e Turismo do Estoril, 2011. http://hdl.handle.net/10400.26/2422.

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Tem sido constatada a relevância da contaminação do ar de ambientes internos. Em ambientes de manipulação de alimentos, para além da questão da saúde dos ocupantes, pode também interferir na qualidade final do produto. O objetivo deste estudo foi avaliar a qualidade microbiológica do ar em áreas de preparação e manipulação de alimentos e zona de exposição do buffet em hotéis do Algarve. Como método de colheita das amostras, foi selecionado o de impactação em meio sólido. Os meios de cultura selecionados foram o PCA (Plate Count Agar) para bactérias e para fungos o Rose Bengal (RB).
The relevance of contamination of the indoors air has been noted. In food handling environments, beside the issue of health of the occupants, the contamination of the indoors air can also interfere in the final product quality. This study aims to evaluate the microbiological air quality in preparation and handling food areas in a buffet area in two hotels in Algarve City, Portugal. The selected method of sampling was solid medium impaction. The culture were selected method was PCA (plate count agar) for bacteria and the Rose Bengal (RB) to fungi. For 15 consecutive days two different hotels were analyzed, at the first one the air samples were collected at the cafe, pastry, gard manger and the area in the buffet restaurant; Hotel kitchen and buffet area in the restaurant at the second one. According to Portuguese law, all air samples for bacteria analysis were within the maximum levels and for fungi, 93.3% of the samples were satisfactory. The values are proposed by the APHA. 71.1% and 53.3% of the samples were satisfactory for bacteria and fungi respectively. Following the Scale’s Fung, 74.5% for bacteria samples were satisfactory, acceptable 24.4% and 1.1% unsatisfactory. As for fungi, 61.3% of samples were satisfactory, 23.3% acceptable and 15.6% unsatisfactory. The study was unable to establish a direct relationship between the results and the weather or the number of people in the kitchens in the days of sampling. Although most environments are analyzed in accordance with current legislation, it is suggested a further deepening in studies that seek to evaluate appropriate limits the situation in Portugal, followed by a review of the amounts set out in legislation, since the existing ones are not specific for the food industry.
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18

Eastwood, Jeremy Peter. "3D bumps : bridging the gap between lift/drag improvement and buffet alleviation?" Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610537.

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19

Alinder, Helena, and Josefin Nilsson. "An Evaluation of the Indian Buffet Process as Part of a Recommendation System." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229424.

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This report investigates if it is possible to use the Indian Buffet Process (IBP), a stochastic process that defines a probability distribution, as part of a recommendation system. The report focuses on recommendation systems where one type of object, for instance movies, is recommended to another type of object, for instance users.         A concept of performing link prediction with IBP is presented, along with a method for performing inference. Three papers that are related to the subject are presented and their results are analyzed together with additional experiments on an implementation of the IBP.        The report arrives at the conclusion that it is possible to use IBP in a recommendation system when recommending one object to another. In order to use IBP priors in a recommendation system which include real-life datasets, the paper suggests the use of a coupled version of the IBP model and if possible perform inference with a parallel Gibbs sampling.
Denna rapport undersöker om det är möjligt att använda Indian Buffet Process (IBP), en stokatisk process som definierar en sannolikhetsfördelning, som en del av ett rekommendationssystem. Rapporten fokuserar på rekommendationssystem där en sorts objekt, exempelvis filmer, rekommenderas till en annan sorts objekt, exempelvis användare.         Ett sätt att förutse länkar, link prediction, mellan olika objekt med hjälp av IBP presenteras tillsammans med en metod för att dra statistiska slutsatser, inference. Tre rapporter som är relaterade till ämnet presenteras och deras resultat analyseras tillsammans med ytterligare experiment på en implementation av IBP.        Rapporten drar slutsatsen att det är möjligt att använda IBP i ett rekommendationssystem då systemet rekommenderar ett objekt till ett annat objekt. Rapporten föreslår en kopplad version av IBP för att kunna använda IBP i ett rekommendationssystem som arbetar på riktigt data samt att inference ska utföras med en parallell Gibbs sampling.
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20

Alvites, Torres Carlos Enrique, and Mendoza Jonathan Josep Prado. "Estudio de pre-factibilidad de un restaurant buffet criollo, en la ciudad de Lima." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2012. http://tesis.pucp.edu.pe/repositorio/handle/123456789/1682.

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Actualmente el Perú está viviendo un ciclo de crecimiento económico basado en políticas macroeconómicas prudentes y correctas. Esto ha llevado a que el Perú crezca 6% en promedio en los últimos años el cual ha sido impulsado principalmente por el consumo interno. Durante el año 2012 se han abierto aproximadamente 10 centros comerciales en el Perú, cada vez más grupos económicos poderosos invierten en negocios relacionados al consumo, tales como el grupo Intercorp, Romero y Brescia. Franquicias como Subway, Starbucks, TacoBell y HardRock café están no solo están retornando al país sino piensan abrir locales en provincias, efecto que años atrás pudo ser impensada. Considerando ello y además que la idiosincrasia del peruano ligada a la aprecio de la comida. En la que toda celebración siempre está alrededor de una mesa de comida, conlleva a estudiar el mercado culinario del Perú en busca de una ventana de oportunidad.
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21

Svärd, Johan. "Saint-Saëns fagottsonat i G-dur : En analys och studie av Saint-Saëns fagottsonat i G-dur (Op.168) och fagottens olika system." Thesis, Kungl. Musikhögskolan, Institutionen för klassisk musik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kmh:diva-2485.

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I följande uppsats har jag skrivit om Saint-Saëns fagottsonat i G-dur, Op.168 och min relation till verket. Arbetet innehåller en studie av kompositörens liv kring tiden då styckets skrevs. Jag har använt olika analysmetoder och valt att analysera stycket ur flera perspektiv, detta för att få en djupare insikt och mer verktyg att arbeta med under min instuderingsprocess. Här får vi en generell analys över verket samt en djupgående mer teoretisk analys av sonatens första sats. I arbetet har jag även studerat fagottens historia och analyserat skillnaderna mellan fagottens uppbyggnad under tiden stycket skrevs i förhållande till dagens moderna fagotter. För att förtydliga detta har jag även valt att analysera två olika tolkningar av stycket, där exekutörerna spelar på fagotter med helt olika konstruktioner. Ett stort fokus ligger även på analysen kring min egen instuderningsprocess där jag tar upp svårigheter, hinder och mitt tillvägagångssätt.
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22

Roberts, Patrick James. "An Experimental Study of Concurrent Methods for Adaptively Controlling Vertical Tail Buffet in High Performance Aircraft." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19863.

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High performance twin-tail aircraft, like the F-15 and F/A-18, encounter a condition known as tail buffet. At high angles of attack, vortices are generated at the wing fuselage interface (shoulder) or other leading edge extensions. These vortices are directed toward the twin vertical tails. When the flow interacts with the vertical tail it creates pressure variations that can oscillate the vertical tail assembly. This results in fatigue cracks in the vertical tail assembly that can decrease the fatigue life and increase maintenance costs. For many years, research has been conducted to understand this phenomenon of buffet and to reduce its adverse effects on the fatigue life of aerospace structures. Many proposed solutions to this tail buffet problem have had limited success. These include strengthening the tail, modifying the vortex flow, using an active rudder control, and leading edge extensions. Some of the proposed active controls include piezoelectric actuators. Recently, an offset piezoceramic stack actuator was used on an F-15 wind tunnel model to control buffet induced vibrations at high angles of attack. The controller was based on acceleration feedback control methods. In this thesis a procedure for designing the offset piezoceramic stack actuators is developed. This design procedure includes determining the quantity and type of piezoceramic stacks used in these actuators. The changes of stresses, in the vertical tail caused by these actuators during an active control, are investigated. In many cases, linear controllers are very effective in reducing vibrations. However, during flight, the natural frequencies of the vertical tail structural system changes as the airspeed increases. This in turn, reduces the effectiveness of a linear controller. Other causes such as the unmodeled dynamics and nonlinear effects due to debonds also reduce the effectiveness of linear controllers. In this thesis, an adaptive neural network is used to augment the linear controller to correct these effects.
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Carn, Cheril, and cheril Carn@dsto defence gov au. "The inverse determination of aircraft loading using artificial neural network analysis of structural response data with statistical methods." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080109.090600.

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An artificial Neural Network (ANN) system has been developed that can analyse aircraft flight data to provide a reconstruction of the aerodynamic loads experienced by the aircraft during flight, including manoeuvre, buffet and distributed loading. For this research data was taken from the International Follow-On Structural Test Project (IFOSTP) F/A-18 fatigue test conducted by the Royal Australian Air Force and Canadian Forces. This fatigue test involved the simultaneous application of both manouevre and buffet loads using airbag actuators and shakers. The applied loads were representative of the actual loads experienced by an FA/18 during flight tests. Following an evaluation of different ANN types an Ellman network with three linear layers was selected. The Elman back-propagation network was tested with various parameters and structures. The network was trained using the MATLAB 'traingdx' function with is a gradient descent with momentum and adaptive learning rate back-propagation algorithm. The ANN was able to provide a good approximation of the actual manoeuvre or buffet loads at the location where the training loads data were recorded even for input values which differ from the training input values. In further tests the ability to estimate distributed loading at locations not included in the training data was also demonstrated. The ANN was then modified to incorporate various methods for the calculation and prediction of output error and reliability Used in combination and in appropriate circumstances, the addition of these capabilities significantly increase the reliability, accuracy and therefore usefulness of the ANN system's ability to estimate aircraft loading.To demonstrate the ANN system's usefulness as a fatigue monitoring tool it was combined with a formulae for crack growth analysis. Results inficate the ANN system may be a useful fatigue monitoring tool enabling real time monitoring of aircraft critical components using existing strain gauge sensors.
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Selin, Janina. "Towards reducing food waste in a hotel breakfast buffet : A case study of Profil Hotels Calmar Stadshotell." Thesis, Linnéuniversitetet, Institutionen för organisation och entreprenörskap (OE), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-76322.

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Food waste is a major environmental issue. It takes electricity, water, and energy to produce food, to store it, to refrigerate it, to transport it and to prepare it. If for some reason the food is then not consumed, it goes to landfill, where it produces greenhouse gases. The fact that food waste is a significant contributor to the tourism industry’s negative impact on the environment has not received as much attention from tourism academics as one could expect, given the magnitude of the problem in tourism, neither has it been given much attention on how to handle it. This study therefore looks into ways to alter consumer food waste as well as identifying the opportunities of food service strategies that allow reducing food waste, while at the same time maintaining the quality of the service at a hotel in Kalmar. The research used social practice theory (SPT) and the concept of service quality as a theoretical framework to guide the collection as well as the analysis. The empirical work of this study consists of two phases, where firstly an exploratory phase was conducted to measure food waste from the breakfast buffet and to conduct a customer survey to point out possible initiatives to reduce food waste. The responses and results were then further analyzed to find patterns and themes which formed the explanatory phase, focusing on assessing the interest of hotel management to adopt solutions reducing food wasted from the breakfast service. The results and analysis proved that most participants, whether consumers or providers, already have a general idea of what sustainable food consumption means as well as engaging in sustainable practices and behaviors. The analysis of the results through the framework of SPT revealed that the factors that motivate participants to engage in sustainable behaviors resonate more to sustainable consumption rather than reducing the consumption, which can be a reason for the vast amount of food waste. However, the results revealed that though there is a growing movement towards reducing food waste as well as straightforward strategies that can be implemented to reduce food waste, there is still a need to try and change the fundamental behaviors to become more sustainable in that matter.
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Silliman, Mary Rachel. "Row crop environments provide an all-you-can-eat buffet and pesticide exposure to foraging honey bees." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/103602.

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The western honey bee, Apis mellifera, provide invaluable economic and ecological services while simultaneously facing stressors that may compromise their health. For example, agricultural landscapes, such as a row crop system, are necessary for our food production, but they may cause poor nutrition in bees from a lack of available nectar and pollen. Row crops are largely wind or self-pollinated, and while previous studies have focused on the impact of bees to row crops, fewer studies have examined the reciprocal relationship of the row crops on honey bees. Here we investigated the foraging dynamics of honey bees in a row crop environment. We decoded, mapped, and analyzed 3460 waggle dances, which communicate the location of where bees collected food, for two full foraging seasons (April – October, 2018-2019), and concurrently collected pollen from returning foragers. We found that bees foraged mostly locally (< 2 km) throughout the season. The shortest communicated median distances (0.48 and 0.32 km), indicating abundant food availability, occurred in July in both years, which was when our row crops were in full bloom. We determined, by plotting and analyzing the communicated locations, that most mid-summer foraging was in row crops, with at least 40% of honey bee recruitment dances indicating either cotton or soybean fields. Bees also largely foraged for nectar when visiting row crop fields, only returning to the hive with Glycine spp. pollen, and foraging on nearby trees and weeds for pollen. Foragers were exposed to thirty-five different pesticides throughout the foraging season, based on pesticide residues in collected pollen. Overall, row crop fields are contributing a surprising majority of mid-summer forage to honey bee hives and suggests that similar agricultural landscapes may also provide abundant, mid-summer forage opportunities for honey bees, however, at the risk of pesticide exposure.
Master of Science in Life Sciences
Declines in the number of honey bee hives have been observed in the United States and western Europe throughout the last century, driven by environmental stressors such as poor nutrition caused by anthropogenic landscape change and pesticide exposure. Agricultural landscapes, for example, contain monocultures and often necessitate pesticide use, which may be detrimental to bee health. Because of these effects, it is necessary to understand how honey bees forage in these systems and what potential health risks they face. We investigated honey bees foraging dynamics in a row crop environment, observing honey bee waggle dance recruitment behavior and gathering forager-collected pollen to better understand when, where, and what honey bees forage on throughout the season (April – October). We found that bees largely foraged near the hive throughout the season, indicating that sufficient resources were available, particularly in July when crops were in full bloom. During full bloom bees considerably foraged in cotton and soybean fields. We found that bees collected minimal row crop pollen, apart from soybean pollen, largely foraging on trees and flowering weeds for pollen. Through pollen foraging bees were exposed to thirty-five pesticides, ranging in toxicity and mode of action. Overall, honey bees foraging in a row crop system foraged substantially in row crop fields during the mid-summer. Row crops systems may be able to provide abundant forage during the mid-summer, but could come at the risk of exposure to pesticides.
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Bayon, De Noyer Maxime P. "Tail buffet alleviation of high performance twin tail aircraft using offset piezoceramic stack actuators and acceleration feedback control." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/12499.

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27

Patel, Umesh. "Control authority and the design of active controllers for buffet suppression of the F-15 and F/A-18." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/12161.

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28

Bérard, Adrien. "Method Development for Computer Aided Engineering for Aircraft Conceptual Design." Licentiate thesis, KTH, Aeronautical and Vehicle Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9240.

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This thesis presents the work done to implement new computational tools and methods dedicated to aircraft conceptual design sizing and optimization. These tools have been exercised on different aircraft concepts in order to validate them and assess their relevance and applicability to practical cases.First, a geometry construction protocol has been developed. It is indeed essential to have a geometry description that supports the derivation of all discretizations and idealizations used by the different analysis modules (aerodynamics, weights and balance, stability and control, etc.) for which an aircraft concept is evaluated. The geometry should also be intuitive to the user, general enough to describe a wide array of morphologies and suitable for optimization. All these conditions are fulfilled by an appropriate parameterization of the geometry. In addition, a tool named CADac (Computer Aided Design aircraft) has been created in order to produce automatically a closed and consistent CAD solid model of the designs under study. The produced CAD model is easily meshable and therefore high-fidelity Computational Fluid Dynamics (CFD) computations can be performed effortlessly without need for tedious and time-consuming post-CAD geometry repair.Second, an unsteady vortex-lattice method based on TORNADO has been implemented in order to enlarge to scope of flight conditions that can be analyzed. It has been validated satisfactorily for the sudden acceleration of a flat plate as well as for the static and dynamic derivatives of the Saab 105/SK 60.Finally, a methodology has been developed to compute quickly in a semi-empirical way the buffet envelope of new aircraft geometries at the conceptual stage. The parameters that demonstrate functional sensitivity to buffet onset have been identified and their relative effect quantified. The method uses a combination of simple sweep theory and fractional change theory as well as the buffet onset of a seed aircraft or a provided generic buffet onset to estimate the buffet envelope of any target geometry. The method proves to be flexible and robust enough to predict within mainly 5% (and in any case 9%) the buffet onset for a wide variety of aircrafts, from regional turboprop to long-haul wide body or high-speed business jets.This work was done within the 6th European framework project SimSAC (Simulating Stability And Control) whose task is to create a multidisciplinary simulation environment named CEASIOM (Computerized Environment for Aircraft Synthesis and Integrated Optimization Methods), oriented toward stability and control and specially suited for aircraft conceptual design sizing and optimization.


SimSAC
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29

Bana, Mohammed. "Complexity perspectives and investment decisions." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/2980.

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Thesis (MPhil (Information Science))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: This thesis investigates investment theory in the light of complexity theory. These insights from diverse fields contain powerful images, metaphors and ways of thinking that allows one to seek new ways of comprehending the nature of the economy and therefore the nature of investment and the related issues of uncertainty and decision making. Complexity theory views the economy as being a dynamic, continuously adaptive, nonlinear system. This is in contrast to traditional or classical economic theory that views the economy as being a simple, linear, equilibrium deterministic system. This thesis is a conceptual study exploring the implications of a complexity worldview for investment decisions by looking at the nature and characteristics of complexity and then overlaying it on the characteristics of the economy. It is argued that complexity is caused by three elements: the structure of the system, human behaviour and exogenous factors. Thereafter follows an analysis of how investment decisions are made in the light of complexity by illustrating the investment models of two very successful, yet different investors: Warren Buffet and George Soros. Buffet’s model hinges on value. He realises that emergent phenomenon driven by irrational behaviour of investors leads to intrinsic values of shares to differ widely from perceived value. When quoted or perceived values are low than it is advisable to purchase as you have a margin of safety. Over the long term the market recognises the real value of the share. He tries to ignore the vagaries of the market and to focus on fundamentals. His list of fundamentals include; the franchise value of the company, quality of management and industry dynamics. George Soros in contrast utilises emergence patterns to locate potential investments. His model is that systems are flawed, human thinking and decision making is flawed and the interaction of the two lead to perturbations and oscillations. He focuses in trying to understand the flaw in systems and in human behaviour and to find some kind of pattern that he could utilise to make a profit. It is shown that both investment models can be understood from a complexity perspective and that these two investors built aspects from complexity into their decision models.
AFRIKAANSE OPSOMMING: Die tesis ondersoek investeringsteorie in die lig van kompleksiteitsteorie. Met die hulp van metafore en insigte vanuit kompleksiteitsdenke word gesoek na nuwe maniere om die aard van die mark en investering verwante aspekte van onsekerheid en besluitneming te verstaan. Die kompleksiteitsperspektief sien die ekonomie as’n dinamiese en aanpassende nie-lineêre sisteem. Dit word gedoen deur die implikasies wat kompleksiteit vir investeringsbesluite inhou konseptueel te ondersoek. Die aard en eienskappe van komplekse sisteme word verduidelik en dan op die ekonomie toegepas. Daar word geargumenteer dat kompleksiteit deur drie elemente veroorsaak word: die struktuur van die sisteem, menslike gedrag en eksogene faktore. Daarna word die praktyk van investeringsbesluite geanaliseer in terme van kompleksiteit duer investeringsmodelle van twee suksesvolle, maar uiteenlopende, investeerders te ondersoek, naamlik Warren Buffet en George Soros. Buffet se model draai rondom waarde. Hy sien die irrasionele gedrag van investeerders as ‘n ontvouende fenomeen wat lei tot ‘n gaping tussen intrinsieke en verwagte waarde. Sy investering word gebaseer op die aanname dat oor die langer termyn die mark die intrinsieke waarde herken. Hy ignoreer dus korttermyn skommelinge in die verwagte waarde en fokus op die fundamentele, waaronder die maanwaarde van die besigheid, die kwaliteit van die bestuur, en industrie-dinamika tel. Soros se model daarenteen gebruik ontvouende patrone en potensiële investeringsgeleenthede te ontbloot. Sy model is dat sisteme inherente teenstrydighede het as ook menslike gedrag en besluitneming. Dit lei tot ossilasies en versteurings. Sy fokus is gerig daarop om hierdie versteurings in die sisteem tot voordeel aan te wend. Daar word getoon hoedat beide investeringsmodelle vanuit ‘n kompleksiteitsperspektief verstaan kan word en dat die twee investeerders sulke aspekte in hulle investeringsbesluite inbou.
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30

Birkenfalk, Sigge. "Hur många luftvärmepumpar har Warren Buffet? eller Är payoffkejsaren naken? : En uppsats om att förväxla företagsekonomiska abstrakta begrepp med privatekonomisk konkret realitet." Thesis, Stockholm University, School of Business, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6407.

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Uppsatsen behandlar payoffbegreppets användning vid privatekonomiska beslut. Författaren visar att privatekonomi och företagsekonomi, två oförenliga paradigm, begreppsmässigt förväxlas och blandas samman i energibranschen Företagsekonomiska abstraktioner utan konkreta motsvarigheter i privatekonomisk praxis skapar osäkerhet, förvirring och tvekan. De aktörer och kunder som undviker paradigmatisk sammanblandning och fokuserar privatekonomiska begrepp går oberörda förbi de svårigheter som annars väntar. Nyckelord: Lönsamhet, payoff, abstraktioner, mentala konstruktioner, privatekonomiska begrepp, företagsekonomiska begrepp, fenomenografi, argumentationsanalys, paradigm.

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31

Ku, Fei Yen. "Towards Automatic Initial Buffer Configuration." Thesis, University of Waterloo, 2003. http://hdl.handle.net/10012/1078.

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Buffer pools are blocks of memory used in database systems to retain frequently referenced pages. Configuring the buffer pools is a difficult and manual task that involves determining the amount of memory to devote to the buffer pools, the number of buffer pools to use, their sizes, and the database objects assigned to each buffer pool. A good buffer configuration improves query response times and system throughput by reducing the number of disk accesses. Determining a good buffer configuration requires knowledge of the database workload. Empirical studies have shown that optimizing the initial buffer configuration (determined at database design time) can improve system throughput. A good initial configuration can also provide a faster convergence towards a favorable dynamic buffer allocation. Previous studies have not considered automating the buffer pool configuration process. This thesis presents two techniques that facilitate the initial buffer configuration task. First, we develop an analytic model of the GCLOCK buffer replacement policy that can be used to evaluate the effectiveness of a particular buffer configuration for a given workload. Second, to obtain the necessary model parameters, we propose a workload characterization scheme that extracts workload parameters, describing the query reference patterns, from the query access plans. In addition, we extend an existing multifractal model and present a multifractal skew model to represent query access skew. Our buffer model has been validated against measurements of the buffer manager of a commercial database system. The model has also been compared to an alternative GCLOCK buffer model. Our results show that our proposed model closely predicts the actual physical read rates and recognizes favourable buffer configurations. This work provides a foundation for the development of an automated buffer configuration tool.
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32

Mercier, Eric. "Jeune peinture et réaction figurative (1948-1959)." Nancy 2, 2005. http://www.theses.fr/2005NAN21015.

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L'opposition entre une abstraction triomphante et une figuration exsangue résume la vision actuelle du débat artistique, en France, pendant les années 50. Si elle en constitue bien la problématique essentielle, constatons qu'entre ces deux "camps", rien n'est encore définitivement joué. La nouvelle génération figurative qui s'exprime au lendemain de la Seconde Guerre mondiale transpose dans ses oeuvres ses interrogations existentielles, reflets de l'angoisse et des incertitudes d'une humanité qui découvre les camps de la mort puis les incertitudes de la guerre froide. Ces jeunes connaissent un succès rapide : la critique les soutient et les impose dans les salons parisiens et au palmarès de nombreux prix. Puis, brutalement, ils sont "lâchés" par le pouvoir culturel et disparaissent des cimaises officielles. Nous expliquons les raisons de cet ostracisme qui perdure aujourd'hui encore
Current thinking about the artistic debat that took place in France during the 1950s is most often encapsulated as being the struggle between triumphant and axhausted figurativism. If this is, indeed, the essential question, one must recognize that nothing has at yet been definitively setteled for the two camps. The present thesis examines the new figurative generation which was active immediately after the Second World War. These young artists transposed into their paintings their existential questions, reflecting the anguish and uncertainty of manking which had just become aware of the concentration camps and the incertainties of the cold war. Success soon came for these youngs painters : the critics encouraged them and insisted that their works be shown in Parisian salons, and that their receive numerous prizes. Then, they were brutally dropped by the cultural establishment. The present thesis explains the reasons for this ostracism which still exists
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33

Santos, Renan Gauthier Cardoso dos [UNESP]. "A festa na metrópole: uma leitura sobre o papel dos buffets na vida cotidiana de São Paulo no século XXI." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/95614.

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Este trabalho analisa o cotidiano da cidade de São Paulo a partir dos espaços destinados a realização de festas – buffets. Delimitamos o bairro de Moema localizado na Região Sul da metrópole paulista para estudar o papel desses serviços na sua relação com a festa. O consumo realizado nesses lugares e o uso de forma temporária também aparecem imersos ao longo da análise. A produção da festa é estudada a partir do desenvolvimento da vida de bairro e da metrópole, que comporta mudanças nos hábitos de consumo para o qual a festa agora possui lugar.
The aim of this study is to investigate the daily life of the city of São Paulo by analyzing places where parties are held – the buffets. We have chosen Moema neighborhood, located in the South Region of São Paulo to study the role of such places in relation to the parties. The consumption taking place in these locations and their occasional use are also objects of this investigation. The production of parties is studied, taking into consideration the neighborhood life and metropolis development, which can shed light into the understanding of consumption habits such as the existence of parties.
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34

Eusébio, Patrícia Santos. "A peixeirada – plano de negócios para um restaurante especializado." Master's thesis, Instituto Superior de Economia e Gestão, 2019. http://hdl.handle.net/10400.5/19957.

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Mestrado em Contabilidade, Fiscalidade e Finanças Empresariais
O plano de negócios surge como o primeiro passo para decidir se o investidor deve ou não investir. Segundo Michael Porter (1996) "a estratégia consiste em fazer escolhas perante situações de trade-off", desta forma é fundamental que as empresas se adequem e façam um plano de negócios antes de proceder a qualquer investimento para não incorrer em riscos desnecessários. Hoje em dia, a experiência do consumidor relativamente ao peixe, vai muito mais para além da simples compra do mercado, este quando procura o produto junto do comércio tradicional vai em busca de uma descoberta de sabor e tradição, aliando a qualidade à arte de comer bem, e é aqui que A Peixeirada se pretende posicionar. Propor ao cliente algo mais que uma mera degustação de pescado é a nossa ambição, pretendemos leva-lo ao que de melhor se encontra na região centro, sobretudo a gastronomia. E se, até aqui, pensa que este seria só mais um projeto de restauração está enganado. Devido à saturação do mercado da restauração em buffets, sobretudo de sushi e rodízios de carne, surge A Peixeirada. Pretendemos oferecer um buffet de degustação, a um preço bastante razoável tendo em conta a qualidade oferecida. Para a elaboração deste projeto foi seguida a metodologia de Harvard (2007). Foram também realizadas entrevistas aos eventuais promotores do projeto para perceber a aceitação do mesmo e também os custos e toda a logística inerente.
The strategic business plan emerges as the first step for to decide whether or not the investor should invest. Second Michael Porter (1996) "strategy is about making choices in situations of trade-offs", in this way it is essential that companies fit in and make a strategic business plan before proceeding to any investment not to incur risks. The project presented is a proposal for a strategic business plan for the A Peixeirada, a possible project that will expand the Eusébio fish shop, to another sector other than the one for which it was created. Nowadays, the consumer's experience of fish goes much further than simply buying the market, this when looking for the product along the traditional trade goes in search of a discovery of flavor and tradition, combining quality to the art of eating well, and this is where the A Peixeirada is intended to position. Proposing to the client something more than a mere tasting of fish is our ambition, we intend to take it to what is best in the center region, especially the gastronomy. And if, so far, you think this would be just another restoration project is mistaken. Due to the saturation of the restoration market in buffets, especially sushi and meat casters, A Peixeirada emerges. We intend to offer a tasting buffet, at a very reasonable price considering the quality offered.
info:eu-repo/semantics/publishedVersion
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35

Kutuchief, Britny Chanel. "Keeping A Straight Face." Cleveland State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=csu1397563089.

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36

Dang, Hong-Phuong. "Approches bayésiennes non paramétriques et apprentissage de dictionnaire pour les problèmes inverses en traitement d'image." Thesis, Ecole centrale de Lille, 2016. http://www.theses.fr/2016ECLI0019/document.

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L'apprentissage de dictionnaire pour la représentation parcimonieuse est bien connu dans le cadre de la résolution de problèmes inverses. Les méthodes d'optimisation et les approches paramétriques ont été particulièrement explorées. Ces méthodes rencontrent certaines limitations, notamment liées au choix de paramètres. En général, la taille de dictionnaire doit être fixée à l'avance et une connaissance des niveaux de bruit et éventuellement de parcimonie sont aussi nécessaires. Les contributions méthodologies de cette thèse concernent l'apprentissage conjoint du dictionnaire et de ces paramètres, notamment pour les problèmes inverses en traitement d'image. Nous étudions et proposons la méthode IBP-DL (Indien Buffet Process for Dictionary Learning) en utilisant une approche bayésienne non paramétrique. Une introduction sur les approches bayésiennes non paramétriques est présentée. Le processus de Dirichlet et son dérivé, le processus du restaurant chinois, ainsi que le processus Bêta et son dérivé, le processus du buffet indien, sont décrits. Le modèle proposé pour l'apprentissage de dictionnaire s'appuie sur un a priori de type Buffet Indien qui permet d'apprendre un dictionnaire de taille adaptative. Nous détaillons la méthode de Monte-Carlo proposée pour l'inférence. Le niveau de bruit et celui de la parcimonie sont aussi échantillonnés, de sorte qu'aucun réglage de paramètres n'est nécessaire en pratique. Des expériences numériques illustrent les performances de l'approche pour les problèmes du débruitage, de l'inpainting et de l'acquisition compressée. Les résultats sont comparés avec l'état de l'art.Le code source en Matlab et en C est mis à disposition
Dictionary learning for sparse representation has been widely advocated for solving inverse problems. Optimization methods and parametric approaches towards dictionary learning have been particularly explored. These methods meet some limitations, particularly related to the choice of parameters. In general, the dictionary size is fixed in advance, and sparsity or noise level may also be needed. In this thesis, we show how to perform jointly dictionary and parameter learning, with an emphasis on image processing. We propose and study the Indian Buffet Process for Dictionary Learning (IBP-DL) method, using a bayesian nonparametric approach.A primer on bayesian nonparametrics is first presented. Dirichlet and Beta processes and their respective derivatives, the Chinese restaurant and Indian Buffet processes are described. The proposed model for dictionary learning relies on an Indian Buffet prior, which permits to learn an adaptive size dictionary. The Monte-Carlo method for inference is detailed. Noise and sparsity levels are also inferred, so that in practice no parameter tuning is required. Numerical experiments illustrate the performances of the approach in different settings: image denoising, inpainting and compressed sensing. Results are compared with state-of-the art methods is made. Matlab and C sources are available for sake of reproducibility
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37

Sartor, Fulvio. "Unsteadiness in transonic shock-wave/boundary layer interactions : experimental investigation and global stability analysis." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4705.

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Dans cette étude nous considérons l'interaction entre une onde de choc et une couche limite turbulente sur un écoulement transsonique sur une bosse d'un point de vue expérimentale et théorique.Des mesures expérimentales ont permis de montrer que l'interaction est caractérisée par la coexistence de deux fréquences caractéristiques distinctes, mais l'origine des oscillations est controversée. Des simulations numériques permettent une description de l'écoulement moyen, mais ne sont pas capables de reproduire le comportement instable de l'interaction. Nous proposons d'abord une étude de stabilité globale: une décomposition en valeurs propres de l'opérateur de Navier-Stokes linéarisé indique que l'interaction est un phénomène stable, et la dynamique de l'écoulement ne peut pas être décrite par un mode global instable.Nous considérons ensuite une approche linéarisée, où la réceptivité de l'écoulement à un forçage externe est analysée à travers une décomposition en valeurs singulières du Résolvant global. Cette nouvelle approche est proposée afin d'expliquer le processus de sélection de fréquence dans cet écoulement, et montre que l'interaction filtre et amplifie le bruit résiduel existant.La même approche est enfin appliquée sur un cas d'écoulement transsonique autour d'un profil d'aile, qui peut présenter des oscillations périodiques de l'onde de choc. La décomposition en valeurs propres de opérateur de Navier-Stokes linéarisé est capable de décrire la dynamique du choc, tandis que la décomposition en valeurs singulières du Résolvant global peut indiquer la présence des instabilité convectives
A transonic interaction between a shock wave and a turbulent boundary layer is experimentally and theoretically investigated. The configuration is a channel flow over a bump, where a shock wave causes the separation of the boundary layer and a recirculating bubble is observed downstream of the shock foot.The mean flow is experimentally investigated by means of PIV, then different techniques allows to identify the main unsteadiness of this shock-wave/boundary-layer interaction. As recognised in similar configurations, the flow presents two distinguished characteristic frequencies, whose origins are still unknown.Numerical simulations are performed solving RANS equations. Results are in good agreement with the experimental mean flow, but the approach fails to predict the unsteady. The solution of RANS equations is then considered as a base flow, and a global stability analysis is performed. Eigenvalue decomposition of the Navier-Stokes operator indicates that the interaction is stable, and the dynamics cannot be described by unstable global modes.A linearised approach based on a singular-value decomposition of the Resolvent is then proposed: the noise-amplifier behaviour of the flow is highlighted by the linearised approach. Medium-frequency perturbations are shown to be the most amplified in the mixing layer, whilst the shock wave behaves as a low-pass filter.The same approach is then applied to a transonic flow over a profile, where the flow can present high-amplitude shock oscillations. The stability analysis can describe both the buffet phenomenon when an unstable mode is present, and the convective instabilities responsible of medium-frequency unsteadiness
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38

Dumon, Jéromine. "Etude expérimentale et numérique du phénomène de tremblement transsonique sur un profil diamant." Thesis, Toulouse, ISAE, 2020. http://www.theses.fr/2020ESAE0009.

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Le développement de lanceurs spatiaux réutilisables nécessite une connaissance appro-fondie des effets des écoulements transsoniques sur la structure du lanceur, commele tremblement transsonique. En effet, l’intégrité mécanique du lanceur peut êtrecompromise par des interactions onde de choc/couche limite. Ces interactions peuventinduire, par exemple, des forces latérales responsables des moments de roulis et detangage, ou une excitation modale de certains éléments de structure pouvant conduireà leur endommagement, voire leur rupture. Ce travail rapporte des études numériqueset expérimentales sur la caractérisation de l’écoulement transsonique autour d’un aileronà profil losangique, conçu pour les lanceurs dédiés aux nanosatellites, avec un intérêtparticulier pour le tremblement transsonique. Ce phénomène a été longuement étudié.Malheureusement, les mécanismes intimes à l’origine du tremblement et la dynamiquedu phénomène sont encore débattus. De plus, il y a un manque d’études sur lesprofils losangiques. Des visualisations strioscopiques résolues en temps, des mesuresde pressions stationnaire et instationnaire pariétales ainsi que des mesures LDV sontréalisées expérimentalement dans une soufflerie transsonique. Les résultats sont comparésà des prédictions numériques basées sur des approches RANS instationnaire et LES. Lestraits tridimensionnels du tremblement transsonique et son caractère chaotique sur unprofil diamant sans flèche sont mis en évidence expérimentalement
The development of reusable space launchers requires a comprehensive knowledge oftransonic flow effects on the launcher structure, such as buffet. Indeed, the mechanicalintegrity of the launcher can be compromised by shock wave/boundary layer interactions.These interactions can induce, amongst others, lateral forces responsible for rolling andpitching moments, or modal excitation of some structural elements that can lead to theirdamage or even failure. This work reports numerical and experimental investigationson the characterization of the transonic flow past a diamond airfoil, designed fornanosatellite-dedicated launchers, with a particular interest for buffeting. Buffeting hasbeen extensively studied. Unfortunately, the detailed mechanisms that are responsiblefor the buffet inception and its dynamics are still debated. Moreover, there is a lackof studies for diamond airfoils. Here, time-resolved Schlieren visualizations, steadyand unsteady pressure measures and LVD measures are experimentally conducted ina transonic wind tunnel. They are compared with numerical predictions based on un-steady RANS and LES approaches. Three dimensional features of buffet over a diamondairfoil without swept, and the occurrence of a chaotic state, are experimentally highlighted
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39

Santos, Renan Gauthier Cardoso dos. "A festa na metrópole : uma leitura sobre o papel dos buffets na vida cotidiana de São Paulo no século XXI /." Rio Claro : [s.n.], 2009. http://hdl.handle.net/11449/95614.

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Orientador: Bernadete A. Caprioglio de Castro Oliveira
Banca: Romualdo Dias
Banca: Carlos Henrique da Costa Silva
Resumo: Este trabalho analisa o cotidiano da cidade de São Paulo a partir dos espaços destinados a realização de festas - buffets. Delimitamos o bairro de Moema localizado na Região Sul da metrópole paulista para estudar o papel desses serviços na sua relação com a festa. O consumo realizado nesses lugares e o uso de forma temporária também aparecem imersos ao longo da análise. A produção da festa é estudada a partir do desenvolvimento da vida de bairro e da metrópole, que comporta mudanças nos hábitos de consumo para o qual a festa agora possui lugar.
Abstract: The aim of this study is to investigate the daily life of the city of São Paulo by analyzing places where parties are held - the buffets. We have chosen Moema neighborhood, located in the South Region of São Paulo to study the role of such places in relation to the parties. The consumption taking place in these locations and their occasional use are also objects of this investigation. The production of parties is studied, taking into consideration the neighborhood life and metropolis development, which can shed light into the understanding of consumption habits such as the existence of parties.
Mestre
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40

Degrutère, Marcel. "L'Orgue à Rouen aux dix-septième et dix-huitième siècles : étude historique et organologique." Paris 4, 1986. http://www.theses.fr/1986PA040081.

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A partir de nombreux documents d'archives inédits, cette étude tend à cerner le phénomène de l'orgue dans une ville, de manière quantitative et qualitative. Apres avoir situé Rouen dans son contexte, ce travail étudie l'aspect historique du phénomène "orgue", en soulignant le rôle des commanditaires, l'activité des facteurs d'orgues et leurs éventuels rapports respectifs. Sur le plan organologique, il s'intéresse à l'entretien des orgues et à l'évolution des buffets de Rouen et des différentes parties de l'instrument
From various unpublished records, this study tends to close in upon the organ phenomena in a town, in a quantitative and qualitative way. After placing Rouen in its right context, this work deals with historical aspect of the organ phenomena and underlines the part played by the commanditaires, the organ-builders' activity and their possible connections. In the organological field, the work concentrates on the organ maintenance and the development of organ-cases in Rouen; it also deals with the different parts of the instrument
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Ueda, Diego Santelli. "Análise econômico-financeira das empresas AMBEV, Coca-Cola e Pepsi com base nos critérios de investimento de Warren Buffett." Universidade Federal do Amazonas, 2016. http://tede.ufam.edu.br/handle/tede/5274.

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Currently, non-alcoholic drinks consumption is shrinking, what was 88.9 liters per person in 2010 increased to 80.6 liters in 2014 (ABIR, 2015). This challenging environment in which they are the beverage industry requires increasing attention of managers and investors in decision-making. Thus, it is through the economic and financial evaluation of investments that can project the success or failure economic, based on the variables that make up the financial statements. However, some investors can get good results even in the face of a negative scenario, is the case of Warren Buffett. Before the above, this study aims to economic and financial analyzing Ambev companies, Coca-Cola and Pepsi based on Warren's investment methodology Buffett proposed the work of Andrade and Koshio (2014) to see if such companies have a competitive advantage long term on the scenario outlined. Therefore, it has the following objectives: i. Identify and compare the criteria of Warren Buffett for each account group, according to the methodology used by Andrade and Koshio (2014); ii. Sort criteria Warren Buffett as the Zurra methodology (2008); iii. Assess whether there is a relationship between the valuation of the price of the Shares to the rating methodology of Warren Buffett criteria via weighting Zurra weight system (2008). The research was classified as the goals as exploratory, descriptive explanatory, using procedures as bibliographic and documentary survey with qualitative and quantitative approach. The results showed that the methodology of Andrade and Koshio (2014) was not sufficient to determine the level of satisfaction of the criteria of Warren Buffett, only determined the level of service to investor criteria. However, when using the Zurra methodology (2008) was able to sort the satisfaction of the criteria of Warren Buffett whose results showed satisfactory level for Coca-Cola, or durable competitive advantage. However, by correlating the historical price of the shares with the classification methodology of Warren Buffett criteria via weighting Zurra weight system (2008) found that Ambev pointed valuation superior to the other companies disproving the results in the classification the satisfaction of Warren Buffett's criteria.
Atualmente, o consumo de bebidas não alcoólicas está encolhendo, o que antes era de 88,9 litros por pessoa em 2010 passou para 80,6 litros em 2014 (ABIR, 2015). Esse ambiente desafiador em que se encontram as indústrias de bebidas requer cada vez mais atenção dos administradores e investidores na tomada de decisão. Assim, é por meio da avaliação econômico-financeira dos investimentos que se pode projetar o sucesso ou insucesso econômico deste, tendo como base as variáveis que compõe os demonstrativos contábeis. Porém, alguns investidores conseguem obter bons resultados mesmo diante de um cenário negativo, é o caso de Warren Buffett. Ante do exposto, o presente trabalho tem como objetivo analisar econômico-financeira as empresas Ambev, Coca-Cola e Pepsi com base na metodologia de investimento de Warren Buffett proposta pelo trabalho de Andrade e Koshio (2014) para saber se tais empresas possuem vantagem competitiva de longo prazo diante do cenário delineado. Para tanto, tem como objetivos específicos: i. Identificar e Comparar os critérios de Warren Buffett para cada grupo de conta, conforme metodologia utilizada por Andrade e Koshio (2014); ii. Classificar os critérios de Warren Buffett conforme a metodologia de Zurra (2008); iii. Avaliar se existe uma relação entre a valorização do Preço das Ações com a metodologia de classificação dos critérios de Warren Buffett via ponderação do sistema de peso de Zurra (2008). A pesquisa foi classificada quanto aos objetivos como exploratória, descritiva explicativa, utilizando como procedimentos o levantamento bibliográfico e documental com abordagem quali-quanti. Os resultados apontaram que a metodologia de Andrade e Koshio (2014) não foi suficiente para determinar o nível de satisfação dos critérios de Warren Buffett, apenas determinaram o nível de atendimento aos critérios do investidor. Porém, ao utilizar a metodologia de Zurra (2008) foi possível classificar a satisfação dos critérios de Warren Buffett cujo resultado apontou nível satisfatório para Coca-Cola, ou seja, vantagem competitiva durável. Contudo, ao correlacionar o preço histórico das ações com o com a metodologia de classificação dos critérios de Warren Buffett via ponderação do sistema de peso de Zurra (2008) verificou-se que a Ambev apontou valorização superior às demais empresas refutando os resultados encontrados na classificação da satisfação dos critérios de Warren Buffett.
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42

Elvira, Clément. "Modèles bayésiens pour l’identification de représentations antiparcimonieuses et l’analyse en composantes principales bayésienne non paramétrique." Thesis, Ecole centrale de Lille, 2017. http://www.theses.fr/2017ECLI0016/document.

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Cette thèse étudie deux modèles paramétriques et non paramétriques pour le changement de représentation. L'objectif des deux modèles diffère. Le premier cherche une représentation en plus grande dimension pour gagner en robustesse. L'objectif est de répartir uniformément l’information d’un signal sur toutes les composantes de sa représentation en plus grande dimension. La recherche d'un tel code s'exprime comme un problème inverse impliquant une régularisation de type norme infinie. Nous proposons une formulation bayésienne du problème impliquant une nouvelle loi de probabilité baptisée démocratique, qui pénalise les fortes amplitudes. Deux algorithmes MCMC proximaux sont présentés pour approcher des estimateurs bayésiens. La méthode non supervisée présentée est appelée BAC-1. Des expériences numériques illustrent les performances de l’approche pour la réduction de facteur de crête. Le second modèle identifie un sous-espace pertinent de dimension réduite à des fins de modélisation. Mais les méthodes probabilistes proposées nécessitent généralement de fixer à l'avance la dimension du sous-espace. Ce travail introduit BNP-PCA, une version bayésienne non paramétrique de l'analyse en composantes principales. La méthode couple une loi uniforme sur les bases orthonormales à un a priori non paramétrique de type buffet indien pour favoriser une utilisation parcimonieuse des composantes principales et aucun réglage n'est nécessaire. L'inférence est réalisée à l'aide des méthodes MCMC. L'estimation de la dimension du sous-espace et le comportement numérique de BNP-PCA sont étudiés. Nous montrons la flexibilité de BNP-PCA sur deux applications
This thesis proposes Bayesian parametric and nonparametric models for signal representation. The first model infers a higher dimensional representation of a signal for sake of robustness by enforcing the information to be spread uniformly. These so called anti-sparse representations are obtained by solving a linear inverse problem with an infinite-norm penalty. We propose in this thesis a Bayesian formulation of anti-sparse coding involving a new probability distribution, referred to as the democratic prior. A Gibbs and two proximal samplers are proposed to approximate Bayesian estimators. The algorithm is called BAC-1. Simulations on synthetic data illustrate the performances of the two proposed samplers and the results are compared with state-of-the art methods. The second model identifies a lower dimensional representation of a signal for modelisation and model selection. Principal component analysis is very popular to perform dimension reduction. The selection of the number of significant components is essential but often based on some practical heuristics depending on the application. Few works have proposed a probabilistic approach to infer the number of significant components. We propose a Bayesian nonparametric principal component analysis called BNP-PCA. The proposed model involves an Indian buffet process to promote a parsimonious use of principal components, which is assigned a prior distribution defined on the manifold of orthonormal basis. Inference is done using MCMC methods. The estimators of the latent dimension are theoretically and empirically studied. The relevance of the approach is assessed on two applications
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43

Palm, Emanuel. "Graphics’ Card Utility withWebGL and N-Buffering : Improving performance using N-buffer strategies with WebGL." Thesis, KTH, Data- och elektroteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-146652.

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This thesis covers the utilization of N buffers in order to reduce resource contention on an abstract WebGL machine, and subsequently freeing up machine processing time. The buffers touched are frame buffers and vertex buffers. The paper also briefly covers the purpose and function of N buffering in relation to graphics and the function of a WebGL machine, the research and production of benchmark prototypes, some relevant benchmark results, and analysis and conclusions. The conclusion is made that the use of N>1 buffering is a potentially viable strategy for increasing WebGL performance, and some theories are outlined and suggestions given for further research to be made for the resolving of how this performance gain may be improved.
Denna uppsats granskar nyttjandet av N buffrar för att minska uppkomsten av resurskonflikter på en abstrakt WebGL maskin, och således frigöra processtid på maskinen i fråga. De typer av buffrar som vidrörs är så kallade frame buffers och vertex buffers. Uppsatsen går också igenom syftet och funktionen hos N buffrar i relation till grafik och funktionen hos en WebGL maskin, förstudien kring och produktionen av prestandatest-prototyper, en del relevanta mätresultat, samt analys och slutsatser. Slutsatsen nås att nyttjandet av N>1 buffrar är en potentiellt gångbar strategi för ökandet av prestanda hos WebGL, och en del teorier presenteras och förslag ges kring ytterligare studier för attöka prestanda ytterligare.
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44

Segee, Molly Catherine. "Surrogate Models for Transonic Aerodynamics for Multidisciplinary Design Optimization." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/71321.

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Multidisciplinary design optimization (MDO) requires many designs to be evaluated while searching for an optimum. As a result, the calculations done to evaluate the designs must be quick and simple to have a reasonable turn-around time. This makes aerodynamic calculations in the transonic regime difficult. Running computational fluid dynamics (CFD) calculations within the MDO code would be too computationally expensive. Instead, CFD is used outside the MDO to find two-dimensional aerodynamic properties of a chosen airfoil shape, BACJ, at a number of points over a range of thickness-to-chord ratios, free-stream Mach numbers, and lift coefficients. These points are used to generate surrogate models which can be used for the two-dimensional aerodynamic calculations required by the MDO computational design environment. Strip theory is used to relate these two-dimensional results to the three-dimensional wing. Models are developed for the center of pressure location, the lift curve slope, the wave drag, and the maximum allowable lift coefficient before buffet. These models have good agreement with the original CFD results for the airfoil. The models are integrated into the aerodynamic and aeroelastic sections of the MDO code.
Master of Science
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45

Bonnifet, Valentin. "Prédiction du phénomène de tremblement sur un profil d'aile avec une approche LES de type PANS-RSM." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS389.

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L'objectif de cette étude est le developpement d'un modèle de sous-maille à équations de transport pour la simulation aux grandes échelles. Le modèle de sous-maille est développé par analogie avec le modèle statistique du second ordre proposé par Gerolymos-Lo-Vallet-Younis. Un paramètre de contrôle constant y est introduit afin de régler la quantité d'énergie cinétique turbulente modélisée par le modèle de sous-maille. Ce paramètre permet un passage continue entre la résolution directe et statistique des équations de Navier-Stokes. Cette approche à la capacité de prédire correctement des écoulements turbulents avec un maillage spatio-temporel plus grossier qu'avec l'approche de la simulation au grandes échelles classique utilisant des modèles de sous-maille algébriques. La méthode proposée est utilisée pour simuler un écoulement transsonique autour du profil d'aile OAT15A. Pour les conditions d'entrées étudiées, cet écoulement est le siège d'une interaction onde de choc couche limite turbulente sur l'extrados du profil d'aile provoquant une oscillation auto-entretenue de la position de l'onde de choc. Les résultats montrent que l'approche développée est apte à reproduire le mouvement de l'onde de choc. Une analyse des grandeurs filtrées de l'écoulement, des corrélations turbulentes ainsi que de l'impact du paramètre de contrôle est présentée. Enfin, cette étude énonce des suggestions de développement pour améliorer le modèle de sous-maille proposé en utilisant un paramètre de contrôle inhomogène en espace et/ou en temps
This PhD was devoted to develop a Large Eddy Simulation subgrid scale model based on transport equations. The subgrid scale model is built in the same manner as second order statistical model suggested by Gerolymos-Lo-Vallet-Younis. A constant control parameter has been introduced to tune the amount of turbulent kinetic energy handled by subgrid scale model. This parameter allows a bridging from Direct Numerical Simulation to Reynolds Averaged Navier-Stokes. This approach can correctly predict turbulent flow with coarser grid and time step than canonical Large Eddy Simulation based on algebraic subgrid scale models where subgrid length scale corresponds to Taylor micro scale. Indeed, the subgrid scale model handles a large part of turbulent kinetic energy in the boundary layer.Transonic flow simulation around OAT15A airfoil is carried out using the suggested approach. On particular inflow conditions, the shock-wave shows a self-sustained motion on the airfoil upper side resulting from the shock-wave boundary layer interaction. Reynolds Averaged Navier-Stokes is not able to predict averaged field because this large unsteadiness is undeterministic and an LES approach is needed. According to the results, the suggested approach can handle shock-wave motion. Filtered flow field, turbulent correlation and control parameter impact analysis are presented. Finally, development ways are suggested in order to improve the subgrid scale model using inhomogeneous control parameter in space and/or time
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46

Nilsson, Alexander, and Kristina Sollander. "INCREASED EFFICIENCY BY PLANNING AN ASSEMBLY LINE WITH SPECIFIC REQUIREMENTS." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-27315.

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Purpose – The purpose with this study is to investigate how an assembly line for products with long cycle time, high product variation and operators who follow the products through the flow can be planned for a high resource utilization as well as the challenges that can arise when planning an assembly line with an increasing demand and how these can be handled. Method – To fulfill the purpose of this study a case study was conducted at Mastec Components AB in Vaggeryd. The empirical data gathered from the case study was obtained through interviews, observations and document studies. The empirical data was then analysed against theory, which means that pattern matching was used and the analyse led to the studies results. Findings – This study illustrates how an assembly line with special demands can be planned to gain high resource utilization. When the products cycle times are multiple they can be sorted into product families to simplify the planning and it also enables a tacted planning method to be used. The study also presents how the usage of time buffers can facilitate the planning of an assembly line. Moreover the study illuminates the importance of controlling tact, both from the customer and the own production. When demand increases it is important that the production line is capable to keep up, therefore some arrangements can be done to reduce waste and increase capacity. Possible alternatives can be buffers, allocating resources and parallel assembly lines. Implications – The study investigates a type of assembly line where the operators follow the products through the flow. This type of assembly line is unexplored in theory and thereby a knowledge gap has been identified which partly have been covered by this study. Further on, the study contributed to an increased understanding of the consequences that occur when operators follow the flow and when products have long varying cycle times. The study also shows the value of calculating tact and use the advantages from it to easier handle variation in demand. Limitations – The case study was performed as one case study which means that only one unit has been analysed. This was due to the lack of resources to do several case studies, both regarding time and ability to find more facilities with similar conditions. If it were possible to conduct more case studies the results could have been more general. Keywords – Tact, tact time, tacted planning, assembly line, planning, operators, buffer.
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47

Franz, Durán Pedro Pablo. "Buffer contracíclico y buffer de conservación de capital: Un análisis crítico." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/148175.

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Ingeniero Civil Industrial
Chile se encuentra actualmente en un proceso de cambios en su regulación bancaria, mediante un proyecto que tiene como fin modificar la Ley General de Bancos (LGB), y así aumentar la solidez del sistema financiero del país. Dentro de las propuestas a implementar, se encuentra la creación de un buffer o colchón de conservación de capital (CCoB) y un buffer contracíclico (CCyB), los cuales corresponden a requisitos de capital adicional por sobre el mínimo obligatorio. El primero de los buffers es constante y equivalente un 2,5 % de los APR, mientras que el segundo es variable y podrá tomar valores entre 0 % y 2,5 % de los APR. La implementación de las normas internacionales propuestas por Basilea conlleva un proceso previo de adaptación de las mismas a la realidad de cada país, ya que todos estos poseen distintas regulaciones y por lo mismo no pueden ser implementadas de la misma forma. Como apoyo a este proceso de adaptación es que se realiza un análisis crítico de ambos buffers. En el análisis del CCoB se obtiene como una de las principales críticas, y mediante un análisis financiero, que el modelo de restricciones a imponer sobre el reparto de utilidades debería ser de forma continua en vez de discreta, con el fin de evitar la perdida de solvencia que posee este último modelo. Por otra parte, se presenta evidencia obtenida mediante revisión de la literatura, sobre la necesidad de restringir todo tipo de pagos discrecionales que hacen uso del Capital Adicional de Nivel 1, ya que de lo contrario los bancos podrían realizar arbitraje regulatorio. Por último, se concluye que es necesario que la entidad reguladora de los bancos posea un nivel de discrecionalidad al momento de exigir el cumplimiento del buffer. El análisis que se realiza sobre el buffer contracíclico comienza con un estudio contrafactual elaborado con datos del Banco Central, donde se muestra el comportamiento del CCyB durante los últimos años. Para comprender el efecto que tendrá este sobre el crecimiento del crédito, se propone seguir la metodología propuesta por Gambacorta y Drehmann (2011), pero al replicar su trabajo no se llega a resultados concluyentes, por lo que se deja propuesta la realización de un estudio econométrico con el fin de determinar las variables que influyen en el crecimiento del crédito. Además, mediante la revisión de literatura, se muestra que la implementación mecánica del CCyB generaría un aumento en la prociclicidad del ciclo económico, mientras que, por otra parte, las alternativas que poseen los bancos para aumentar su índice de capital, podrían generar resultados contrarios a los buscados por Basilea.
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48

Khan, Jamal Ahmad. "Improving TCP Data Transportation for Internet of Things." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/84946.

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Internet of Things (IoT) is the idea that every device around us is connected and these devices continually collect and communicate data for analysis at a large scale in order to enable better end user experience, resource utilization and device performance. Therefore, data is central to the concept of IoT and the amount being collected is growing at an unprecedented rate. Current networking systems and hardware are not fully equipped to handle influx of data at this scale which is a serious problem because it can lead to erroneous interpretation of the data resulting in low resource utilization and bad end user experience defeating the purpose of IoT. This thesis aims at improving data transportation for IoT. In IoT systems, devices are connected to one or more cloud services over the internet via an access link. The cloud processes the data sent by the devices and sends back appropriate instructions. Hence, the performance of the two ends of the network ie the access networks and datacenter network, directly impacts the performance of IoT. The first portion of the our research targets improvement of the access networks by improving access link (router) design. Among the important design aspects of routers is the size of their output buffer queue. %Selecting an appropriate size of this buffer is crucial because it impacts two key metrics of an IoT system: 1) access link utilization and 2) latency. We have developed a probabilistic model to calculate the size of the output buffer that ensures high link utilization and low latency for packets. We have eliminated limiting assumptions of prior art that do not hold true for IoT. Our results show that for TCP only traffic, buffer size calculated by the state of the art schemes results in at least 60% higher queuing delay compared to our scheme while achieving almost similar access link utilization, loss-rate, and goodput. For UDP only traffic, our scheme achieves at least 91% link utilization with very low queuing delays and aggregate goodput that is approx. 90% of link capacity. Finally, for mixed traffic scenarios our scheme achieves higher link utilization than TCP only and UDP only scenarios as well as low delays, low loss-rates and aggregate goodput that is approx 94% of link capacity. The second portion of the thesis focuses on datacenter networks. Applications that control IoT devices reside here. Performance of these applications is affected by the choice of TCP used for data communication between Virtual Machines (VM). However, cloud users have little to no knowledge about the network between the VMs and hence, lack a systematic method to select a TCP variant. We have focused on characterizing TCP Cubic, Reno, Vegas and DCTCP from the perspective of cloud tenants while treating the network as a black box. We have conducted experiments on the transport layer and the application layer. The observations from our transport layer experiments show TCP Vegas outperforms the other variants in terms of throughput, RTT, and stability. Application layer experiments show that Vegas has the worst response time while all other variants perform similarly. The results also show that different inter-request delay distributions have no effect on the throughput, RTT, or response time.
Master of Science
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49

Martin, Amy. "Does religion buffer cheating?" Thesis, Northern Illinois University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3611371.

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Given the current amount of cheating in our society and more specifically in our schools, the focus of this dissertation was to examine the impact of religiosity on cheating behavior in an academic arena. Additionally social norms and the individual difference variable of self-monitoring were also investigated to determine their impact on cheating behavior. Furthermore, self-regulation was examined to determine if non-cheating high self-monitors deplete more self-regulatory resources than those non-cheating low self-monitors in a cheating situation.

Participants completed a religiosity and self-monitoring measure prior to coming into the laboratory. At a date of their choosing, participants completed the laboratory portion of the study. In the laboratory, participants were given a job-competency measure to complete, at which time they were given an opportunity to cheat. The participants completed the job-competency measure alone or in the presence of a confederate. Four different conditions were formed: a control condition, a cheating condition, a passive condition, and an active noncheating condition. It was also in the laboratory that their grip strength was measured.

Contrary to expectations, religiosity was not a significant predictor of cheating behavior. However, norms did impact cheating behavior; there was more cheating when the confederate cheated and less cheating when the confederate discouraged cheating behavior. Additionally, there was an impact of self-monitoring in response to the created norms, such that high self-monitors tended to follow the behaviors of the confederates more so than low self-monitors. Contrary to expectations, self-regulatory resources were not significantly impacted for noncheating high self-monitors in a confederate-induced cheating condition.

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50

Tian, Zhao. "Buffer-aided cooperative networks." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/19041.

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In this thesis new methods are presented to achieve performance enhancement in wireless cooperative networks. In particular, techniques to improve diversity gain, throughput and minimise the transmission delay are described. A buffer-aided amplify-and-forward max-link relay selection scheme for both symmetric and asymmetric channels is introduced. This approach shows that the max-link scheme is most effective over the traditional max-SNR scheme when the source-to-relay and relay-to-destination links are symmetric. The closed form expressions for the outage probability and average packet delay of the proposed scheme under both symmetric and asymmetric channel configurations is derived. The diversity order and the coding gain of the AF max-link scheme is analytically provided. Then a novel relay selection scheme with significantly reduced packet delay is proposed. Both the outage performance and average packet delay of the proposed scheme are analysed. The analysis shows that, besides the diversity and coding gains, the proposed scheme has average packet delay similar to that of a non buffer-aided relay system when the channel SNR is sufficiently high thereby. A novel buffer-aided link selection scheme based on network-coding in a multiple hop relay network is proposed. Compared with existing approaches, the proposed scheme significantly increases the system throughput. This is achieved by applying data buffers at the relays to decrease the outage probability and using network-coding to increase the data rate. The closed-form expressions of both the average throughput and packet delay are derived. The proposed scheme has not only significantly higher throughput than both the traditional and existing buffer-aided max-link scheme, but also smaller average packet delay than the max-link scheme. A decode-and-forward buffer-aided relay selection for the underlay cognitive relay networks in the presence of both primary transmitter and receiver is presented. A novel buffer aided relay selection scheme for the cognitive relay network is proposed, where the best relay is selected with the highest signal-to-interference-ratio among all available source-to-relay and relay-to-destination links while keeping the interference to the primary destination within a certain level. A closed-form expression for the outage probability of the proposed relay selection scheme is obtained. Finally, A novel security buffer-aided decode-and-forward cooperative wireless networks is considered. An eavesdropper which can intercept the data transmission from both the source and relay nodes is considered to threaten the security of transmission. Finite size data buffers are assumed to be available at every relay in order to avoid having to select concurrently the best source-to-relay and relay-to-destination links. A new max-ratio relay selection policy is proposed to optimise the secrecy transmission by considering all the possible source-to-relay and relay-to-destination links and selecting the relay having the link which maximises the signal to eavesdropper channel gain ratio. Two cases are considered in terms of knowledge of the eavesdropper channel strengths: exact and average gains, respectively. Closed-form expressions for the secrecy outage probability for both cases are obtained. The proposed max-ratio relay selection scheme is shown to outperform one based on max-min-ratio relay scheme.
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