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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The Key to Unlocking the Secret Window

McConnell, Sarah E. 12 1900 (has links)
David Koepp's Secret Window was released by Columbia Pictures in 2004. The film's score was written by Philip Glass and Geoff Zanelli. This thesis analyzes transcriptions from six scenes within the film in conjunction with movie stills from those scenes in an attempt to explain how the film score functions.
42

Strömfördelning i triangulära elektrokroma fönster / Current Distribution in Triangular Electrochromic Windows

Molin Andersson, Sofie January 2016 (has links)
One of the world’s largest energy user is the building sector, where much of the energy goes to cooling of buildings. There is need for novel technology to reduce this energy usage, and one way is to install electrochromic windows. They have the ability to vary the transmittance of visible and infrared light by the application of a small electrical voltage, and hence to save large amounts of energy and money and to increase indoor comfort by avoiding strong glares from sunlight. This study concentrates on thin-film electrochromic devices that are based on flexible polyester foils. The conventional design is to make rectangular devices with contacts placed on transparent conductor layers opposite of each other. An electric potential is applied between the contacts, generating an electric field which causes ions to move between films of electrochromic active materials. Since there is an interest on the market for electrochromic windows of other geometries, such as triangular, there is a need to know how to place the contacts in order to obtain a rapid and uniform colouring and bleaching of the device. In order to investigate this, a mathematical model describing the current distribution over the device is a great tool. The model used in this study takes secondary current distribution into account, which includes ohmic effects and electrode kinetics, but neglects diffusive effects due to the assumption that the electrolyte is homogeneous. It describes the two dimensional ohmic flow through the transparent conductor films, the local current due to electrochemical effects in the electrochromic active materials, and a correlation between the optical properties and the injected charge over time. The model is simulated using FlexPDE, which solves the system of differential equations using a Finite Elements Method (FEM). To adjust model parameters, model simulation results are compared to experimental data from rectangular electrochromic devices. Initially, experiments are done on small are devices on which current distribution effects are small. The model is then further developed and validated using large area rectangular devices with 67 cm between the contacts. The model is shown to meet the aims of this study, which is to obtain a simulation tool which can predict the trend in the transmittance distribution. The strength of having this model at hands is that it becomes possible to simulate the transmittance behaviour over time for full size electrochromic windows of different geometries, without having to manufacture expensive devices for experiments. It provides a great design tool for optimizing a rapid and uniform colouring and bleaching, and to investigate how to reduce material costs without affecting performance too much. In this study an example which shows the strength of the model is given. The placement of contacts and its effect on the transmittance distribution in triangular electrochromic windows is examined. It shows that the current distribution model enables time-efficient and cheap design of electrochromic windows.
43

PROBABILITY OF FALSE POLYNOMIAL DIVISION SYNCHRONIZATION USING SHORTENED CYCLIC CODES

Schauer, Anna Lynn, Ingels, Frank M. 11 1900 (has links)
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Shortened cyclic codes are not cyclic, but many cyclic shifts of various code words are still part of the shortened code set. This paper addresses the probability of false synchronization obtained through polynomial division of a serial shortened cyclic code stream in a “sliding” window correlator.
44

Metamaterial window glass for adaptable energy efficiency

Mann, Tyler Pearce 02 October 2014 (has links)
A computational analysis of a metamaterial window design is presented for the purpose of increasing the energy efficiency of buildings in seasonal or cold climates. Commercial low-emissivity windows use nanometer-scale Ag films to reflect infrared energy, while retaining most transmission of optical wavelengths for functionality. An opportunity exists to further increase efficiency through a variable emissivity implementation of Ag thin-film structures. 3-D finite-difference time-domain simulations predict non-linear absorption of near-infrared energy, providing the means to capture a substantial portion of solar energy during cold periods. The effect of various configuration parameters is quantified, with prediction of the net sustainability advantage. Metamaterial window glass technology can be realized as a modification to current, commercial low-emissivity windows through the application of nano-manufactured films, creating the opportunity for both new and after-market sustainable construction. / text
45

Contrôle actif du rayonnement acoustique des plaques : une approche à faible autorité/Active control of sound radiation from plates : a low authority approach

De Man, Pierre 04 June 2004 (has links)
L'objectif de cette thèse consiste en l'étude d'une stratégie de contrôle actif à faible autorité avec comme application le contrôle actif du rayonnement acoustique d'une plaque. Depuis l'essor du contrôle actif, son application aux problèmes acoustiques et vibracoustiques a été investiguée par de nombreux chercheurs, exploitant soit la théorie du contrôle optimal, soit des approches originales basées plus particulièrement sur la physique. Des notions spécifiques au contrôle vibroacoustique ont été développées comme, par exemple, les modes radiatifs pouvant caractériser le rayonnement acoustique d'une plaque d'une manière adaptée au contrôle. Le contrôle actif à faible autorité, pour lequel le Laboratoire de Structures Actives a développé une expertise dans le domaine de l'amortissement et du contrôle actif des vibrations, est une solution attractive par sa simplicité de mise en oeuvre. Le plus souvent implémenté sous la forme d'un contrôle décentralisé constitué de boucles indépendantes, le contrôle à faible autorité bénéficie de certaines garanties de stabilité et de robustesse. Bien que notre stratégie de contrôle puisse s'appliquer à n'importe quel type de plaque, l'application considérée dans ce travail a été motivée par le contexte socio-économique actuel en rapport avec les nuisances acoustiques. Il était en effet intéressant d'évaluer la stratégie de contrôle pour le problème de la transmission acoustique d'un vitrage. La stratégie de contrôle se divise en deux étapes. Tout d'abord le développement d'un capteur unique destiné à fournir une mesure représentative du bruit rayonné par une plaque en basse fréquence. Deux capteurs de vitesse volumétrique (l'un discret, l'autre distribué) ont ainsi été développés et évalués expérimentalement. Ensuite, une procédure d'optimisation de l'emplacement d'un ensemble d'actionneurs pilotés en parallèle est proposée. L'objectif de cette phase d'optimisation est de forcer la réponse fréquentielle du système à posséder les propriétés d'un système colocalisé. La stratégie de contrôle est ensuite évaluée sur deux structures expérimentales. / This thesis is concerned with a low authority active control strategy applied to the sound radiation control of a baffled plate. Since the development of active control , numerous researchers have studied its application to acoustical or vibroacoustical problems using either the modern control theory or other methods based rather on the understanding of the physics of the problem. Vibroacoustical active control has lead to the definition of radiation modes allowing to describe the radiated sound of a plate in an appropriate manner for active control purposes. Low autorithy control (LAC), for which the Active Structures Laboratory has gained an expertise for active vibration control applications is an interesting solution for its implementation simplicity. Most of the time it consists of several decentralized control loops, and benefits from guaranteed stability and robustness properties. Although our control strategy can be applied to any kind of plates, the application considered here has been motivated by the present socio-economical context related to noise annoyances. The active control strategy has been applied the problem of the sound transmission loss of glass plates (windows). This strategy is in two steps : first a volume velocity sensor is developed as to give a measure representative of the radiated sound at low frequencies. Two sensors have been developed (one discrete and one distributed) and experimentally tested. Next, an optimisation strategy is proposed which allow to locate on the plate a set of several actuators driven in parallel. The goal of this optimisation task is to obtain an open-loop frequency response which behave like a collocated system. The control strategy is finally evaluated on two plate structures.
46

Reliable user datagram protocol (RUDP).

Thammadi, Abhilash January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Gurdip Singh / As the network bandwidth and delay increase, TCP becomes inefficient. Data intensive applications over high-speed networks need new transport protocol to support them. This project describes a general purpose high performance data transfer protocol as an application level solution. The protocol Reliable UDP-based data transfer works above UDP with reliability. Reliable Data Transfer protocol provides reliability to applications using the Sliding Window protocol (Selective Repeat). UDP uses a simple transmission model without implicit handshaking techniques for providing reliability and ordering of packets. Thus, UDP provides an unreliable service and datagrams may arrive out of order, appear duplicated, or go missing without notice. Reliable UDP uses both positive acknowledgements and negative acknowledgements to guarantee data reliability. Both simulation and implementation results have shown that Reliable UDP provides reliable data transfer. This report will describe the details of Reliable UDP protocol with simulation and implementation results and analysis.
47

A software assistant for manual stereo photometrology

Sheer, Paul January 1997 (has links)
A dissertation submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of master of Science in Engineering. / A software package was written under the X Window System, Version 11, to assist in manual stereopsis of multiple views. The package enables multiple high resolution (2000 by 1500 pixels and higher) black and white photographs to be viewed simultaneously. Images have adjustable zoom windows which can be manipulated with the pointing device. The zoom windows enlarge to many times the resolution of the image enabling sub-pixel measurements to be extrapolated by the operator. A user-friendly interface allows for fast pinhole camera calibration (from known 3D calibration points) and enables three dimensional lines, circles, grids, cylinders and planes to be fitted to markers specified by the user. These geometric objects are automatically rendered in 3D for comparison with the images. The camera calibration is performed using an iterative optimisation algorithm which also tries multiple combinations of omitted calibration points. This allows for some fault tolerance of the algorithm with respect to erroneous calibration points. Vector mathematics for the geometrical fits is derived. The calibration is shown to converge on a variety of photographs from actual plant surveys. In an artificial test on an array of constructed 3D coordinate markers, absolute accuracy was found to be 1 mm (standard deviation of the Euclidean error) for a distance of 2.5 meters from a standard 35 mm camera. This translates to an error of 1.6 pixels in the scanned views. Lens distortion was assumed to be negligible, except for aspect ratio distortion which was calibrated for. Finally. to demonstrate the efficacy of the package, a 3D model was reconstructed from ten photographs of a human face, taken from different angles. / AC2017
48

Exploration Framework For Detecting Outliers In Data Streams

Sean, Viseth 27 April 2016 (has links)
Current real-world applications are generating a large volume of datasets that are often continuously updated over time. Detecting outliers on such evolving datasets requires us to continuously update the result. Furthermore, the response time is very important for these time critical applications. This is challenging. First, the algorithm is complex; even mining outliers from a static dataset once is already very expensive. Second, users need to specify input parameters to approach the true outliers. While the number of parameters is large, using a trial and error approach online would be not only impractical and expensive but also tedious for the analysts. Worst yet, since the dataset is changing, the best parameter will need to be updated to respond to user exploration requests. Overall, the large number of parameter settings and evolving datasets make the problem of efficiently mining outliers from dynamic datasets very challenging. Thus, in this thesis, we design an exploration framework for detecting outliers in data streams, called EFO, which enables analysts to continuously explore anomalies in dynamic datasets. EFO is a continuous lightweight preprocessing framework. EFO embraces two optimization principles namely "best life expectancy" and "minimal trial," to compress evolving datasets into a knowledge-rich abstraction of important interrelationships among data. An incremental sorting technique is also used to leverage the almost ordered lists in this framework. Thereafter, the knowledge abstraction generated by EFO not only supports traditional outlier detection requests but also novel outlier exploration operations on evolving datasets. Our experimental study conducted on two real datasets demonstrates that EFO outperforms state-of-the-art technique in terms of CPU processing costs when varying stream volume, velocity and outlier rate.
49

Análise da satisfação dos clientes de uma loja de automóveis usados na Serra Gaúcha

Fantoni, Gustavo January 2017 (has links)
Este trabalho teve o objetivo de mensurar o grau de satisfação dos clientes de uma loja de automóveis usados na serra gaúcha. O número de questionários coletados ao final da pesquisa foi de 146 entrevistados, possibilitando a criação de um perfil destes. O método utilizado foi de cunho exploratório, descritivo e explicativo. Para a coleta de dados, utilizou-se o um formulário baseado na escala Likert, que permitiu avaliar questões relativas à importância baseada no nível de concordância de uma afirmação. A partir das médias obtidas, aplicou-se uma série de ferramentas de análise. A principal delas foi a “Janela do Cliente”. A intenção foi descrever os principais atributos apontados a melhorar, sendo os principais e mais relevantes: flexibilidade na negociação, financiamento próprio, tempo de resposta, qualidade dos automóveis, promoções, taxa de juros, horário de atendimento, qualidade no atendimento, iluminação da loja, agilidade no atendimento, disposição dos carros e comprometimento. Também foi aplicada a ferramenta análise de variância (ANOVA), onde observamos a maioria dos atributos listados, com seus respectivos resultados. A análise de regressão serviu para apurar que 5 atributos foram eleitos como de maior relevância para os entrevistados, sendo a variável com maior impacto positivo sobre a satisfação geral dos clientes a flexibilidade na negociação. Por fim, com a análise fatorial foi possível criar grupos de variáveis que se relacionam, identificando 5 grupos de importância, classificados como: aparência estrutura e precificação, habilidade e negociação, disponibilidade da equipe, solicitude ao cliente e confiança. / This work had the objective of measuring the degree of customer satisfaction of a used car shop in the state of Rio Grande do Sul. The number of questionnaires collected at the end of the survey was 146 interviewees, making it possible to create a profile of these. The method used was exploratory, descriptive and explanatory. For data collection, a form based on the Likert scale was used, which allowed to evaluate questions related to the importance based on the level of agreement of an affirmation. From the averages obtained, a series of analysis tools were applied. The main one was the "Client Window". The intention was to describe the main attributes aimed at improving, being the main and most relevant: flexibility in negotiation, own financing, response time, car quality, promotions, interest rate, service hours, service quality, store lighting , Agility in service, car layout and commitment. We also applied the analysis of variance (ANOVA) tool, where we observed most of the listed attributes, with their respective results. The regression analysis served to ascertain that 5 attributes were chosen as of greater relevance for the interviewees, being the variable with the greatest positive impact on the general satisfaction of the clients the flexibility in the negotiation. Finally, with the factorial analysis it was possible to create groups of variables that are related, identifying 5 groups of importance, classified as: structure and pricing appearance, skill and negotiation, team availability, client solicitude and trust.
50

A refugee crisis as a policy window : a case study on the Hungarian immigration policy change in 2015

Fagerström, Simon January 2017 (has links)
The escalating conflict in Syria that started in 2011 would cause millions of Syri- ans to flee the country. It is estimated that as much as 7,6 million Syrians were displaced internally and 3,7 million externally. This initially caused an enormous pressure on neighboring countries were refugees were displacing to (Ostrand 2011: 1-2). Though as the years passed the large majority of externally displaced refugees stayed in the neighboring states, though this would change in 2015 (UNHCR 2013: 1-3). In the spring of 2015 several ships either sank or were abandoned in the Mediterranean resulting in fatalities. Though as an increasing amount of refugees reached the southern member states of the EU it created an immense pressure on the immigration handling processes of the affected countries such as Italy and Greece (Livingstone, Cerelus 2016). A large amount of refugees would then start moving up throughout eastern Europe towards northern countries such as Germany and Swe- den. Though it won’t be long until Hungary decides to fence in its southern border to prevent refugees from passing through the country. As criticism flourished from the EU, member states of the EU, and other organizations, Hungary did not alter its policy, but instead came to further deteriorate the relations by defending its political position (Than, Krisztina 2017). This was done even though Hungary is heavily dependent on monetary support from the European Union as well as access to its Schengen zone (European Union 2017). Little research has been done on this matter where countries such as Hungary, Poland and Slovakia amongst others have decided to challenge the basic principles of free movement and the Dublin treaty after the refugee crisis. This senior thesis aim to look at how Hungary could have been able to do a immigration policy change that stands in contrast to that of the EU while they are in many ways dependent on the Schengen zone and financial support from the EU.

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