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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

Efeito de solvente no espectro de absorção da 5-fluorouracil. Análise de diferentes procedimentos teóricos / Solvent Effect on the 5-fluorouracil absorption spectrum, Analysis od different theoretical procedures

Silva, Carlos Eduardo Bistafa da 25 February 2011 (has links)
A molécula 5-fluorouracil (5FU) é muito utilizada em tratamentos de câncer. Seu espectro de absorção é caracterizado por duas bandas de diferentes intensidades, as transições n-p* e p-p*, e seu estudo em diferentes solventes é de considerável importância para compreender a fotofísica do estado excitado. Este é o primeiro passo essencial para obter a caracterização da dinâmica de emissão. Neste trabalho, nós estudamos teoricamente o espectro de absorção da 5FU em dois solventes, água e acetonitrila, usando o método Sequential Quantum Mechanics/ Molecular Mechanics (SQM/MM). Uma etapa importante para uma simulação realista é a polarização do soluto pelo solvente. Neste estudo, esta polarização foi obtida usando dois modelos: Polarizable Continuum Model (PCM), que é uma alternativa simples e um método iterativo usando Average Solvent Electrostatic Configuration (ASEC). Após isso, simulações usando Monte Carlo Metrópolis no ensemble NVT em condições normais de temperatura e pressão foram realizadas e configurações estatisticamente descorrelacionadas separadas para subsequentes cálculos de Mecânica Quântica usando diversos métodos: Configuration Interaction (CI), Time Dependent Density Functional Theory (TD-DFT) e um método semi-empírico (INDO/CIS). Os espectros calculados em ambos os solventes foram obtidos em mais de uma aproximação: contínua, discreta e explícita. Os resultados estão em boa concordância com os valores experimentais e enfatizam a importância da inclusão de moléculas de solvente explícitas nos cálculos. Nós especialmente notamos que em solventes, a transição n-p* é deslocada para o azul enquanto a transição p-p* é deslocada para o vermelho, indicando uma tendência para reversão dessas duas bandas se comparadas à fase gasosa. Isto aponta para diferenças na fotofísica, dependendo da polaridade do solvente. Os resultados também permitem uma avaliação dos diferentes procedimentos teóricos utilizados. / The 5-fluorouracil molecule is very used in cancer treatment. Its absorption spectrum is characterized by two broad bands of different intensities, the n-p* and p-p* transitions, and its study in different solvents is of considerable importance for the understanding of the photophysics of the excited state. It is the first essential step for obtaining the characterization of the emission dynamics. In this work we have theoretically studied the absorption spectrum of 5FU in two solvents, water and acetonitrile, using the Sequential Quantum Mechanics/Molecular Mechanics method (SQM/MM). An important step for a realistic simulation is the polarization of the solute by the solvent. In this study, this polarization was obtained by using two models: Polarizable Continuum Model (PCM), which is a simple alternative, and an iterative method using the Average Solvent Electrostatic Configuration (ASEC). After this, Monte Carlo Metropolis simulations in the NVT ensemble in normal conditions of temperature and pressure were made and statistically uncorrelated configurations sampled for the subsequent Quantum Mechanics calculations using several methods: Configuration Interaction (CI), Time Dependent Density Functional Theory (TD-DFT) and a semiempirical method (INDO/CIS). The calculated spectra in both solvents were obtained using more than one approach: continuum, discrete and explicit. The results are in good agreement with experimental values and emphasize the importance of explicitly including solvent molecules. We specially note that in solvents, the n-p* is blue-shifted and the p-p* transition is red-shifted leading to a tendency for reversal of these two bands compared to gas phase. This points to differences in the photophysics, depending on the solvent polarity. The results also allow an evaluation of the different theoretical procedures used.
2

Efeito de solvente no espectro de absorção da 5-fluorouracil. Análise de diferentes procedimentos teóricos / Solvent Effect on the 5-fluorouracil absorption spectrum, Analysis od different theoretical procedures

Carlos Eduardo Bistafa da Silva 25 February 2011 (has links)
A molécula 5-fluorouracil (5FU) é muito utilizada em tratamentos de câncer. Seu espectro de absorção é caracterizado por duas bandas de diferentes intensidades, as transições n-p* e p-p*, e seu estudo em diferentes solventes é de considerável importância para compreender a fotofísica do estado excitado. Este é o primeiro passo essencial para obter a caracterização da dinâmica de emissão. Neste trabalho, nós estudamos teoricamente o espectro de absorção da 5FU em dois solventes, água e acetonitrila, usando o método Sequential Quantum Mechanics/ Molecular Mechanics (SQM/MM). Uma etapa importante para uma simulação realista é a polarização do soluto pelo solvente. Neste estudo, esta polarização foi obtida usando dois modelos: Polarizable Continuum Model (PCM), que é uma alternativa simples e um método iterativo usando Average Solvent Electrostatic Configuration (ASEC). Após isso, simulações usando Monte Carlo Metrópolis no ensemble NVT em condições normais de temperatura e pressão foram realizadas e configurações estatisticamente descorrelacionadas separadas para subsequentes cálculos de Mecânica Quântica usando diversos métodos: Configuration Interaction (CI), Time Dependent Density Functional Theory (TD-DFT) e um método semi-empírico (INDO/CIS). Os espectros calculados em ambos os solventes foram obtidos em mais de uma aproximação: contínua, discreta e explícita. Os resultados estão em boa concordância com os valores experimentais e enfatizam a importância da inclusão de moléculas de solvente explícitas nos cálculos. Nós especialmente notamos que em solventes, a transição n-p* é deslocada para o azul enquanto a transição p-p* é deslocada para o vermelho, indicando uma tendência para reversão dessas duas bandas se comparadas à fase gasosa. Isto aponta para diferenças na fotofísica, dependendo da polaridade do solvente. Os resultados também permitem uma avaliação dos diferentes procedimentos teóricos utilizados. / The 5-fluorouracil molecule is very used in cancer treatment. Its absorption spectrum is characterized by two broad bands of different intensities, the n-p* and p-p* transitions, and its study in different solvents is of considerable importance for the understanding of the photophysics of the excited state. It is the first essential step for obtaining the characterization of the emission dynamics. In this work we have theoretically studied the absorption spectrum of 5FU in two solvents, water and acetonitrile, using the Sequential Quantum Mechanics/Molecular Mechanics method (SQM/MM). An important step for a realistic simulation is the polarization of the solute by the solvent. In this study, this polarization was obtained by using two models: Polarizable Continuum Model (PCM), which is a simple alternative, and an iterative method using the Average Solvent Electrostatic Configuration (ASEC). After this, Monte Carlo Metropolis simulations in the NVT ensemble in normal conditions of temperature and pressure were made and statistically uncorrelated configurations sampled for the subsequent Quantum Mechanics calculations using several methods: Configuration Interaction (CI), Time Dependent Density Functional Theory (TD-DFT) and a semiempirical method (INDO/CIS). The calculated spectra in both solvents were obtained using more than one approach: continuum, discrete and explicit. The results are in good agreement with experimental values and emphasize the importance of explicitly including solvent molecules. We specially note that in solvents, the n-p* is blue-shifted and the p-p* transition is red-shifted leading to a tendency for reversal of these two bands compared to gas phase. This points to differences in the photophysics, depending on the solvent polarity. The results also allow an evaluation of the different theoretical procedures used.
3

Congestion Management at the Network Edge

Daneryd, Oscar January 2014 (has links)
In the Internet of today there is a demand for both high bandwidth and low delays. Bandwidth-heavy applications such as large downloads or video streaming compete with more delay-sensitive applications; web-browsing, VoIP and video games. These applications represent a growing share of Internet traffic. Buffers are an essential part of network equipment. They prevent packet loss and help maintain hight throughput. As bandwidths have increased so have the buffer sizes. In some cases way to much. This, and the fact that Active Queue Management (AQM) is seldom implemented, has given rise to a phenomenon called Bufferbloat. Bufferbloat is manifested at the bottleneck of the network path by large flows creating standing queues that choke out smaller, and usually delay-sensitive, flows. Since the bottleneck is often located at the consumer edge, this is where the focus of this thesis lies. This work evaluates three different AQM solutions that lower delays without requiring complicated configuration; CoDel, FQ_CoDel and PIE. FQ_CoDel had the best performance in the tests, with the lowest consistent delays and high throughput. This thesis recommends that AQM is implemented at the network edge, preferably FQ_CoDel.
4

Mejoramiento de factores operacionales de proyectos nuevos pozos

Álvarez Rivas, Carlos Alberto January 2013 (has links)
Magíster en Gestión y Dirección de Empresas / Este emprendimiento se crea por la necesidad de buscar herramientas de gestión en el ámbito de proyectos que se desarrollan en la Gerencia de Producción de Mina, Pozas y Servicios de la Empresa SQM Salar. Este mejoramiento tiene como finalidad aumentar la extracción del área mina, mediante mejoramiento de factores operacionales en las etapas de implementación de los proyectos de nuevos pozos de extracción, que den como resultado menores tiempos de implementación, mayor disponibilidad y confiabilidad operativa. Las áreas que involucra este análisis son dependientes directamente de la Vicepresidencia de Operaciones Salar Litio y que incluyen a la Gerencia de proyectos y Gerencia de Operaciones Mina. Históricamente ha existido la sensación que los proyectos de la Gerencia de Producción Mina, Pozas y Servicios se pudieron desarrollar de mejor forma logrando que la operación se ajustara a los parámetros de proyecto en los plazos y costos estimados. Por lo mismo se realiza una búsqueda de alternativas y/o mejores prácticas que permita tener una guía general que nos oriente hacia metodologías probadas que lleven a lograr un mejor desempeño. Para que esta investigación tenga validez desde el punto de vista de una propuesta formal, es necesario contar con el apoyo de los interesados, que en este caso incluyen principalmente a áreas de proyecto y operaciones, lo cual, debido al profesionalismo que presentan los integrantes de los equipos mencionados se logra sin mayor dificultad. Cabe señalar que el pilar fundamente que hace posible el desarrollo de este trabajo, consiste en que el objetivo está muy bien entendido por todos los involucrados en la organización y que consiste en aumentar la capacidad de extracción de la Mina a través de proyectos de expansión.
5

Selecting the best strategy to improve quality, keeping in view the cost and other aspects

Karahasanovic, Ermin, Lönn, Henrik January 2007 (has links)
The purpose with the thesis was to create a general model that can help companies to take the best decision when it comes to improving the quality of an object. The model was created to solve the problem formulation; How to find the best way to improve the quality of an object, focusing primarily on the relationship between cost and quality but also take other important aspects into consideration. Before the model was created a literature study was performed in ELIN without any useable result. After the literature study was performed quality models like Quality Function Deployment (QFD) and Total Quality Management (TQM) were studied. The study of QFD and TQM showed that they are somewhat complicated and often consider the entire organisation. Simple Quality Model is a smaller model and focuses only at one object at a time. TQM and QFD have however been good inspiration for the creation of SQM. The model was tested in a real-time situation at Saab Communication. Together with Saab Communication we decided to apply SQM to the Swedish defence telenetwork (FTN). In FTN the model was tested at the basic connections. SQM generated 7 different alternatives to improve the dependability in a basic connection. After the application of SQM it showed that alternative 7 was the best alternative. Alternative 7 was to decrease the switch over time. The switch over is today not handled by a special employee and is instead shared among several workers. By employing two new employees there is a possibility to lower the switch over time with 50% down from today’s 60 minutes to 30. To implement this alternative would bring a cost of 5 374 034 SEK and a quality increase of 0,1398955% for the basic connections in the Swedish defence tele-network.
6

Selecting the best strategy to improve quality, keeping in view the cost and other aspects

Karahasanovic, Ermin, Lönn, Henrik January 2007 (has links)
<p>The purpose with the thesis was to create a general model that can help companies to take the best decision when it comes</p><p>to improving the quality of an object. The model was created to solve the problem formulation; How to find the best way to</p><p>improve the quality of an object, focusing primarily on the relationship between cost and quality but also take other</p><p>important aspects into consideration. Before the model was created a literature study was performed in ELIN without any</p><p>useable result. After the literature study was performed quality models like Quality Function Deployment (QFD) and Total</p><p>Quality Management (TQM) were studied. The study of QFD and TQM showed that they are somewhat complicated and</p><p>often consider the entire organisation. Simple Quality Model is a smaller model and focuses only at one object at a time.</p><p>TQM and QFD have however been good inspiration for the creation of SQM. The model was tested in a real-time situation</p><p>at Saab Communication. Together with Saab Communication we decided to apply SQM to the Swedish defence telenetwork</p><p>(FTN). In FTN the model was tested at the basic connections. SQM generated 7 different alternatives to improve</p><p>the dependability in a basic connection. After the application of SQM it showed that alternative 7 was the best alternative.</p><p>Alternative 7 was to decrease the switch over time. The switch over is today not handled by a special employee and is</p><p>instead shared among several workers. By employing two new employees there is a possibility to lower the switch over time</p><p>with 50% down from today’s 60 minutes to 30. To implement this alternative would bring a cost of 5 374 034 SEK and a</p><p>quality increase of 0,1398955% for the basic connections in the Swedish defence tele-network.</p>
7

Impact of coordination challenges on quality of global software development projects

Nekkanti, Lakshmi Sowjanya January 2016 (has links)
Context. Global software development (GSD) gained huge recognition in today’s business world. Most of the software companies day by day are striving hard to evolve globally where software is developed in the context of different environmental settings that are distanced on various factors like geography, timezone, culture and language. Coordination is the factor that plays one of the prominent roles in such a setting for effective teamwork and project success. Although numerous efforts has been done in this research area, there has been no proper evidence from industry about the impact of these coordination challenges on the overall quality of the software when being developed in a distributed setting. Objectives. The purpose of this study is to examine and identify the coordination challenges and risks faced in global software development projects that has a negative impact on the quality of software from practitioner’s perspective. It also identify the tools, methods, and techniques that are used in industry to overcome these challenges and maintain quality standards. Methods. The aims and objectives of our study are fulfilled by conducting survey among practitioners working in GSD projects all around the globe. Further, 10 interviews are conducted with practitioners working in different companies and geographical locations in order to gain a detailed understanding of the impact of identified coordination challenges on the quality of software in GSD projects. Results. A total of 50 survey responses are recorded, out of which 48 respondents specify that coordination challenges has a negative impact on software quality in GSD context. By the ratings given by the participants, we identified the challenges and risks that had a major impact. Mixed results are obtained during interviews where most of them prioritized coordination as a major problem in GSD projects. It also included that use of some tools, methods and processes help them in overcoming this issue. The quality attributes that are mostly affected due to the challenges in GSD projects are also identified. Conclusions. After the analysis of survey results, the coordination challenges and associated risks in GSD projects are identified. They were found to havemostly negative impact on software quality. After thematic analysis of interview results, we observed that though the impact of coordination challenges is negative, its extent of implication is moderate in most cases.
8

Světelné znečištění v okolí hvězdárny Ondřejov / Light pollution in the vicinity of the Ondřejov Observatory

Kocourek, David January 2017 (has links)
Light pollution is currently one of the environmental problems of human society. With the technological development and the increase of the human population on the planet, the landscape is constantly increasing the emission of disturbing light into the surrounding area during the night. The largest producer of light pollution is the urban and suburban regions where light spreads to several decades away, increasing the brightness of the sky, as well as rural or nature-close landscapes. Exposure to disturbing light has a demonstrably unfavorable effect on human, animal and plant health as well as on the balance of whole ecosystems. In this work I focus on finding and assessing the state of sky brightness in the interest zone of the observatory of Astronomical Institute AV at Ondřejov. Based on my own data measured in the field during nine night excursions, I created an interpolated map of ArcMap 10.2 and, according to directional measurements, interpreted the main polluters in this area. The results clearly show a clear trend to reduce the sky's brightness from the northwest to the east. The measurements also show that the local sources of obstrusive light near Ondřejov have a slight influence on the overall zenith brightness of the sky compared to the presence of Prague, several miles away....
9

Quantifizierung von Synergiepotentialen bei der Bewertung von Bankenzusammenschlüssen /

Frank, Regina. January 2005 (has links)
Univ., Diss. u.d.T.: Regina Frank "Quantifizierung von Synergiepotentialen im Rahmen der Bewertung von Zusammenschlüssen von Universalbanken"--Bremen, 2002. / Literaturverz. S. 281 - 329.
10

Nástroj pro analýzu uživatelských dat získaných z instalací AVG Admin Konzole / Tool for Analysis of User Data Gathered from AVG Admin Console Installations

Heroutová, Tereza January 2012 (has links)
This document describes the design and implementation of a tool which allows for evaluation and visualisation of statistical data gathered from users of the AVG Admin Console application. The document describes collected statistical data including their localization and storing all the data in the database is discussed. The application was tested on real statistical data and possible improvements based on the results are proposed.

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