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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.
1

A theoretical investigation of the propagation of waves in non-uniform waveguides

Smith, N. H. January 1986 (has links)
No description available.
2

Forces modulating the folding of Bacteriorhodopsin

Allen, Samantha Jane January 2002 (has links)
No description available.
3

E Pluribus Unum: A Study of Reconnecting a Broken Urban Fabric

Haecker, Krystyn 05 July 2013 (has links)
A city requires the architecture that comprises it to stitch together its urban fabric, creating connections between various, potentially disconnected, parts. Architecture mediates its surrounding public and open spaces, including plazas, streets, and parks. To fully understand a site of a future development, it is first important to understand the current and future conditions of the area within which the site is located, and in some cases its historical context as well. Only then can designers produce architecture that responds to and provides for its urban context for current and future generations. By studying the current, historic, and future contexts of Banneker Overlook, this thesis was developed by a thorough understanding of its site as a means of influencing the program and future architectural design. Banneker Overlook in its current state is a disconnected urban park in Southwest Washington, DC, originally intended as a connection point between two parts of the city. The purpose of this thesis is to reconnect the higher L'enfant Promenade with the lower Maine Avenue and Southwest Waterfront by means of the architecture and exterior public spaces. The program chosen for the site is a large public museum called the National Museum of the American People. It will "tell the story of ALL of the American People from prehistoric times to the present" (National Museum of the American People).  A large cultural building was used because of its capability to pull Washington residents and visitors to a single location coming from various, possibly disconnected, parts of the city. As a product of the site conditions, this thesis along with its site and building program became a study of creating connections of places, spaces, ideas, and people over time and space in an attempt to understand how architecture could represent this idea at both an urban and building scale. All of these ideas can be represented in our original national motto: E Pluribus Unum, "Out of Many, One." / Master of Architecture
4

Connecting Core Concepts with Everyday Chemistry

Miraflores-Barizo, Ophelia 08 1900 (has links)
<p> The rationale for this project is based on the recognition that chemistry courses tend to be taught too much from a theoretical standpoint, with little reference to everyday life. This is one of the reasons that a majority of students think that chemistry is difficult, boring, tedious, and uninteresting (Worthy, 1982). If they have the choice, many students would rather not take a chemistry course, and if they do, it will probably be their last course in Chemistry.</p> <p> It is the intent of the Ontario Curriculum Guidelines to provide some science-technology-society connections. The aim of this project is to provide supplemental science-technology society connections, and selected concrete examples of practical, everyday chemistry for teachers, so that they may enrich their classes, motivate their students, and put theory into an appropriate context. If classes are more interesting and relevant to the world of the students, then more students could be motivated to take chemistry courses and consider continuing to more advanced classes. A second purpose for this project is to stimulate a typical non-science student's interest in chemistry and science. It is even more necessary to motivate these students by providing interesting connections with the real world and suitable applications of theory and principles. These connections with the real world are important for such students, so that they will be better able to make informed decisions as scientifically literate citizens, managers, or politicians, not only for themselves, but for the benefit of society as a whole.</p> <p> To accomplish the aims of this project, two or three short hand-outs of practical everyday chemistry were prepared for each of the core topics in the Grade 11 (SCH 3A) and Chemistry OAC (SCH OA) courses. A few of the examples included Dental Chemistry, Culinary Chemistry, Insect Pheromones, and Teflon.</p> <p> Results of the survey taken from chemistry teachers showed that these hand-outs would better motivate students to study chemistry. Teachers think it is useful for their classes. They would like a compilation of these examples, if one were to be made available.</p> / Thesis / Master of Science (Teaching)
5

Exploratory Data Analysis using Clusters and Stories

Hossain, Mahmud Shahriar 25 July 2012 (has links)
Exploratory data analysis aims to study datasets through the use of iterative, investigative, and visual analytic algorithms. Due to the difficulty in managing and accessing the growing volume of unstructured data, exploratory analysis of datasets has become harder than ever and an interest to data mining researchers. In this dissertation, we study new algorithms for exploratory analysis of data collections using clusters and stories. Clustering brings together similar entities whereas stories connect dissimilar objects. The former helps organize datasets into regions of interest, and the latter explores latent information by connecting the dots between disjoint instances. This dissertation specifically focuses on five different research aspects to demonstrate the applicability and usefulness of clusters and stories as exploratory data analysis tools. In the area of clustering, we investigate whether clustering algorithms can be automatically "alternatized" and how they can be guided to obtain alternative results using flexible constraints as "scatter-gather" operations. We demonstrate the application of these ideas in many application domains, including studying the bat biosonar system and designing sustainable products. In the area of storytelling, we develop algorithms that can generate stories using distance, clique, and syntactic constraints. We explore the use of storytelling for studying document collections in the biomedical literature and intelligence analysis domain. / Ph. D.
6

The Study of Optoelectronic Characteristics and Charge Generation Mechanism in White Organic Light-Emitting Diode with Tandem Structure

Liu, Chia-Chun 24 August 2011 (has links)
Recently, tandem white organic light-emitting diodes are attracting a great deal of interest due to their potential illumination applications. A tandem structure is a mean two or more electroluminescence units that joined together through connecting units in series. So, we can make sense that the connecting unit has play an important role in this particular structure. In my paper research, the functions of connecting units are usually being considered with two aspects: charge transporting and charge generation. But, it was rarely discussed which function is the key point. Three devices were fabricated in this study : (¢¹) unit device, (¢º) tandem device 1 with connecting layers of Alq3:Li/MoO3 and (¢») tandem device 2 with connecting layers of Alq3:Li/HAT-CN. Base on this two connecting unit structure, we can get a quantifiable data from adopting, carrier transporting and carrier generation and figure out which function of connecting unit in tandem device is the main factor. The unit device has outstanding performance comparing to others fluorescence white OLED. It exhibits a maximum luminance of 49820 cd/m2 at 1755 mA/cm2, the power efficiency of 2.52 lm/W at 20 mA/cm2 and CIE (0.33, 0.33). But the power efficiency decreased to 2.07 lm/W at 20 mA/cm2 in tandem device 1. In order to improve device performance, we choose new material HAT-CN to replace to MoO3. From our result, the tandem device 2 have increase power efficiency from 2.07 lm/W to 2.24 lm/W at 20 mA/cm2, and the maximum luminance reach 71790 cd/m2 at 650 mA/cm2 with CIE(0.30, 0.39). We want to figure out why the power efficiency increased after using HAT-CN in tandem device. So we further designed and fabricated the hole only device, electron only device and capacitance device to figure out the charge transporting and charge generation behavior between these two connecting unit constructed based on Alq3:Li/MoO3 and Alq3:Li/HAT-CN. After analyzing the results of these devices, we found that the charge generating plays a major role in tandem OLED¡¦s performance. In other words, if the more carriers can be generated in the connecting layers, the higher power efficiency in tandem device can be realized.
7

Train : from spaces of potential to places of interaction

Kleinhans, Erika 07 December 2012 (has links)
This dissertation investigates the role of Architecture in promoting participation, interaction and awareness of the public in sporting activities, specifically with regard to the underprivileged community of Hammanskraal. The problems with the existing sports facilities are the following: * the location of the facilities; and * the fact that even though they are public facilities, they do not necessarily act as public spaces. They are fenced off and cover a vast area of land without providing proper shade for the players and spectators. The proposed intervention addresses these problems through the introduction of sports facilities into the public realm. This is achieved through locating of these facilities next to a new railway station and pedestrian and vehicle route that crosses over the railway line (Fig 3). The proposal intends to create a threshold space for members of the community in which to interact through sport, trade, social and cultural activities. The programme will provide sports training fields, a multi -functional hall, a gymnasium, a station and retail facilities. The architectural response is informed by the following : * the amalgamation of sports facilities with the public space; * programmatic requirements; and * responses to contextual conditions. / Dissertation MArch(Prof)--University of Pretoria, 2012. / Architecture / Unrestricted
8

New Belgrade’s Cultural Spine: Revitalization of the spaces lost to the Highway E75

Prostran, Nikola January 2022 (has links)
New Belgrade’s Cultural Spine: Revitalization of the spaces lost to the Highway E75 is a Masterplan project that has a healing aspect to the city fabric and public life. Belgrade is a city located at the confluence of the Sava and Danube rivers which divide the city into three parts. Still, besides this division, there is also a Highway that has a disruptive effect on the city fabric.  How do the communities surrounding the highway interact with it? How they can use the space which now is not possible? The project is about communities and heritage adjacent to the highway. How to provide access to it? Focusing on New Belgrade’s Central Zone, this project provides the model that is an alternative to the model of big developments, instead of covering up empty sites, it is trying to rethink their function and create a cultural spine that is desperately forgotten in this part of the city.
9

Estabilidade assintótica e estrutural de campos vetoriais / Asymptotic and Structural Stability of Vector Fields

Pires, Benito Frazão 01 August 2006 (has links)
O objetivo deste trabalho é provar um Closing Lema Parcial para variedades bidimensionais compactas, orientáveis ou não--orientáveis. Para enunciá--lo, considere um campo vetorial \\linebreak $X\\in\\mathfrak^r(M)$, $r\\ge 2$, de classe $C^r$ em uma variedade bidimensional compacta $M$, e seja $\\Sigma$ um segmento transversal a $X$ passando por um ponto recorrente não--trivial $p$ de $X$. Seja $P:\\Sigma\\to\\Sigma$ a correspondente transformação de primeiro retorno. O primeiro resultado deste trabalho consiste em mostrar que se $P$ tem a propriedade de que para todo $n\\ge N$ e $x\\in{m dom}\\,(P^n)$, $\\vert DP^n(x)\\vert<\\lambda$, onde $N\\in\\N$ e $0<\\lambda<1$, então existe um campo vetorial $Y$ arbitrariamente próximo de $X$ na topologia $C^r$ tendo uma trajetória periódica passando por $p$. O segundo resultado consiste em apresentar condições, sobre os expoentes de Lyapunov de $P$, para que $\\vert DP^n\\vert<\\lambda$ para todo $n\\ge N$. Nesta tese, também incluímos um resultado sobre a estabilidade assintótica no infinito de campos planares diferenciáveis, mas não necessariamente de classe $C^1$. / The aim of this work is to provide a Partial $C^r$ Closing Lemma for compact surfaces, orientable or non--orientable. To state it, let $X\\in\\mathfrak^r(M)$, $r\\ge 2$, be a $C^r$ vector field on a compact surface $M$ and let $\\Sigma$ be a transverse segment to $X$ passing through a non--trivial recurrent point $p$ of $X$. Let $P:\\Sigma\\to\\Sigma$ be the corresponding first return map. The first result of this work consists in showing that if $P^n$ has the property that for all $n\\ge N$ and $x\\in{m dom}\\,(P^n)$, $\\vert DP^n(x)\\vert<\\lambda$, where $N\\in\\N$ e $0<\\lambda<1$, then there exists a vector field $Y$ arbitrarily close to $X$ in the $C^r$ topology such that $p$ is a periodic point of $Y$. The second result consists in presenting sufficient conditions, upon the Lyapunov exponents of $P$, so that $\\vert DP^n\\vert<\\lambda$ for all $n\\ge N$. In this thesis, we also include a result concerning the asymptotic stability at infinity of planar differentiable vector fields, not necessarily of class $C^1$.
10

Estabilidade assintótica e estrutural de campos vetoriais / Asymptotic and Structural Stability of Vector Fields

Benito Frazão Pires 01 August 2006 (has links)
O objetivo deste trabalho é provar um Closing Lema Parcial para variedades bidimensionais compactas, orientáveis ou não--orientáveis. Para enunciá--lo, considere um campo vetorial \\linebreak $X\\in\\mathfrak^r(M)$, $r\\ge 2$, de classe $C^r$ em uma variedade bidimensional compacta $M$, e seja $\\Sigma$ um segmento transversal a $X$ passando por um ponto recorrente não--trivial $p$ de $X$. Seja $P:\\Sigma\\to\\Sigma$ a correspondente transformação de primeiro retorno. O primeiro resultado deste trabalho consiste em mostrar que se $P$ tem a propriedade de que para todo $n\\ge N$ e $x\\in{m dom}\\,(P^n)$, $\\vert DP^n(x)\\vert<\\lambda$, onde $N\\in\\N$ e $0<\\lambda<1$, então existe um campo vetorial $Y$ arbitrariamente próximo de $X$ na topologia $C^r$ tendo uma trajetória periódica passando por $p$. O segundo resultado consiste em apresentar condições, sobre os expoentes de Lyapunov de $P$, para que $\\vert DP^n\\vert<\\lambda$ para todo $n\\ge N$. Nesta tese, também incluímos um resultado sobre a estabilidade assintótica no infinito de campos planares diferenciáveis, mas não necessariamente de classe $C^1$. / The aim of this work is to provide a Partial $C^r$ Closing Lemma for compact surfaces, orientable or non--orientable. To state it, let $X\\in\\mathfrak^r(M)$, $r\\ge 2$, be a $C^r$ vector field on a compact surface $M$ and let $\\Sigma$ be a transverse segment to $X$ passing through a non--trivial recurrent point $p$ of $X$. Let $P:\\Sigma\\to\\Sigma$ be the corresponding first return map. The first result of this work consists in showing that if $P^n$ has the property that for all $n\\ge N$ and $x\\in{m dom}\\,(P^n)$, $\\vert DP^n(x)\\vert<\\lambda$, where $N\\in\\N$ e $0<\\lambda<1$, then there exists a vector field $Y$ arbitrarily close to $X$ in the $C^r$ topology such that $p$ is a periodic point of $Y$. The second result consists in presenting sufficient conditions, upon the Lyapunov exponents of $P$, so that $\\vert DP^n\\vert<\\lambda$ for all $n\\ge N$. In this thesis, we also include a result concerning the asymptotic stability at infinity of planar differentiable vector fields, not necessarily of class $C^1$.

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