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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.
131

Analysis of Order Strategies for Alternating Algorithms in Optimization

Ntiamoah, Daniel 05 June 2023 (has links)
No description available.
132

EVALUATION OF SPHERICITY USING MODIFIED SEQUENTIAL LINEAR PROGRAMMING

SARAVANAN, SHANKAR January 2005 (has links)
No description available.
133

Browser Based Visualization for Parameter Spaces of Big Data Using Client-Server Model

Glendenning, Kurtis M. 09 September 2015 (has links)
No description available.
134

A study of casting distortion and residual stresses in die casting

Garza-Delgado, Abelardo January 2007 (has links)
No description available.
135

Oriented 3D Printing

El Sahi, Simon Boliver January 2008 (has links)
<p> Ink-jet printing onto flat paper is a widely established process. In this thesis, we make extensions to printing on target surfaces such as metals and glass, using a 5-axis orientable head. Original artwork is created using CAD, and is sampled to create the ink jet point cloud. The target surface location is registered using a standard Coordinate Measuring Machine (CMM) 5-axis touch trigger probe. The probe is then replaced with the ink jet head and the printing process is carried out. Demonstration of the system is illustrated using flat metal and glass samples, as well as rapid prototyped 3-D plastic shapes.</p> / Thesis / Master of Applied Science (MASc)
136

NetClust: A Framework for Scalable and Pareto-Optimal Media Server Placement

Yin, H., Zhang, X., Zhan, T.Y., Zhang, Y., Min, Geyong, Wu, D.O. January 2013 (has links)
No / Effective media server placement strategies are critical for the quality and cost of multimedia services. Existing studies have primarily focused on optimization-based algorithms to select server locations from a small pool of candidates based on the entire topological information and thus these algorithms are not scalable due to unavailability of the small pool of candidates and low-efficiency of gathering the topological information in large-scale networks. To overcome this limitation, a novel scalable framework called NetClust is proposed in this paper. NetClust takes advantage of the latest network coordinate technique to reduce the workloads when obtaining the global network information for server placement, adopts a new Kappa -means-clustering-based algorithm to select server locations and identify the optimal matching between clients and servers. The key contribution of this paper is that the proposed framework optimizes the trade-off between the service delay performance and the deployment cost under the constraints of client location distribution and the computing/storage/bandwidth capacity of each server simultaneously. To evaluate the performance of the proposed framework, a prototype system is developed and deployed in a real-world large-scale Internet. Experimental results demonstrate that 1) NetClust achieves the lower deployment cost and lower delay compared to the traditional server selection method; and 2) NetClust offers a practical and feasible solution for multimedia service providers.
137

An Algorithm and System for Measuring Impedance in D-Q Coordinates

Francis, Gerald 10 May 2010 (has links)
This dissertation presents work conducted at the Center for Power Electronics Systems (CPES) at Virginia Polytechnic Institute and State University. Chapter 1 introduces the concept of impedance measurement, and discusses previous work on this topic. This chapter also addresses issues associated with impedance measurement. Chapter 2 introduces the analyzer architecture and the proposed algorithm. The algorithm involves locking on to the voltage vector at the point of common coupling between the analyzer and the system via a PLL to establish a D-Q frame. A series of sweeps are performed, injecting at least two independent angles in the D-Q plane, acquiring D- and Q-axis voltages and currents for each axis of injection at the point of interest. Chapter 3 discusses the analyzer hardware and the criteria for selection. The hardware built ranges from large-scale power level hardware to communication hardware implementing a universal serial bus. An eight-layer PCB was constructed implementing analog signal conditioning and conversion to and from digital signals with high resolution. The PCB interfaces with the existing Universal Controller hardware. Chapter 4 discusses the analyzer software. Software was written in C++, VHDL, and Matlab to implement the measurement process. This chapter also provides a description of the software architecture and individual components. Chapter 5 discusses the application of the analyzer to various examples. A dynamic model of the analyzer is constructed, considering all components of the measurement system. Congruence with predicted results is demonstrated for three-phase balanced linear impedance networks, which can be directly derived based on stationary impedance measurements. Other impedances measured include a voltage source inverter, Vienna rectifier, six-pulse rectifier and an autotransformer-rectifier unit. / Ph. D.
138

Translational Neuroimaging of Emotion Processes in Posttraumatic Stress Disorder and Depression

McCurry, Katherine Lorraine 14 August 2020 (has links)
Disrupted emotion processes are central features of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD), which are linked to altered neural response patterns. However, inconsistent results have led to questions about the reliability of such findings. Heterogeneous clinical presentations across individuals with PTSD and MDD are likely to be associated with heterogeneous neurobehavioral changes which may differ depending on the emotion process studied. Similarly, neurobehavioral signatures of treatment response prediction may vary based on the task or context probed. In these studies, we examined how neuroimaging of emotion processes may shed light on mechanisms underlying symptom heterogeneity in PTSD (Study 1) and how similar neuroimaging signatures may be useful for predicting response to MDD treatment (Study 2). Results showed re-experiencing and hyperarousal symptoms had opponent effects on neural habituation to negative images, such that while increasing severity of hyperarousal symptoms was related to diminished habituation, increasing severity of re-experiencing symptoms was associated with enhanced habituation. Additionally, across MDD studies, two regions of the brain, the right anterior insula and the subgenual anterior cingulate cortex, exhibited pretreatment responses to negative emotional stimuli that were predictive of clinical response to treatment. Considered together, this work demonstrates the translational utility of neuroimaging of negative emotion processes to enhance our understanding of symptomatology and treatment prediction in PTSD and MDD. / Ph.D. / People who have posttraumatic stress disorder (PTSD) or depression often notice changes in the intensity and range of emotions they experience. These changes are thought to be related to differences in how the brain processes emotional information. Using neuroimaging to visualize changes that occur in the brains of individuals with PTSD or depression when they are experiencing negative emotions, we may gain a better understanding of how their symptoms are impacting them and how they may respond to different types of treatments. In these studies, I used brain imaging to measure responses to emotional images of people with and without PTSD. I found that certain PTSD symptoms affected the way people's brains responded over time to negative and neutral images. More several arousal symptoms were linked to less decreases of brain responses over time or less habituation. More severe symptoms of intrusive memories or distress when exposed to reminders of trauma were associated with greater decreases of brain responses to negative images. In a second study, I found that across studies of people with depression, two regions of the brain that are involved in emotion processing and stress responsivity, show pretreatment responses to negative emotional stimuli that are related to how they are likely to respond to treatment for depression. Overall, my research demonstrates how brain responses to negative emotions may be useful for understanding symptoms of mental health disorders and may help with predicting how individuals will respond to treatment.
139

Modeling and predicting the performance of coordinate measuring machines

Talabgaew, Sompoap 01 April 2003 (has links)
No description available.
140

Estudo de um formalismo para discretizar eficientemente as equações integrais do Método da Coordenada Geradora Hartree-Fock / The study of a formalism to discretize efficiently the integral equations of the generator coordinate Hartree-Fock method

Chahad, Alexandre Pereira 09 June 2009 (has links)
A busca por um conjunto de bases de alta qualidade é feita por vários grupos, pois a utilização destes conjuntos é importante para a obtenção de resultados exatos, tanto para propriedades atômicas quanto para propriedades moleculares. Os conjuntos usados neste trabalho são constituídos através da utilização do Método da Coordenada Geradora Hartree-Fock em sua versão polinomial e foram construídos de forma a permitirem uma maior flexibilidade à camada de valência do átomo, flexibilidade esta que foi proporcionada pelo número de funções que descrevem a última camada do átomo. Uma nova metodologia para a construção de conjuntos de base foi proposta neste trabalho. Esta nova metodologia diminui a busca artesanal pela busca pelos conjuntos de base introduzindo o Método Simplex em nosso programa gerador de base GENBASIS minimizando o tempo de procura por essa bases de qualidade. A aplicação destes conjuntos para estimativa de propriedades atômicas e moleculares foi feita em comparação com conjuntos de base largamente utilizados na literatura, envolvendo cálculos com vários níveis de teoria, desde o método Hartree-Fock até a Teoria do Funcional Densidade. / The search for high quality basis set is made by several groups since the quality of the basis sets is a very important factor to obtain accurate results for atomic and molecular properties. The basis sets used in this work are designed by using the polynomial Generate Coordinate Method and were constructed with the aim to improve the flexibility of a basis sets to describe the valence shell. A new methodology for the search of this basis set is proposed in this work. This new methodology makes the search for this basis set less artisanal with the introduction of the Simplex Method in our basis generator program, GENBASIS. This introduction minimizes the time used in the search for these quality basis set. The application of our basis sets in atomic and molecular calculations were compared with the most used basis sets in the literature and were performed by using different level of calculations, namely, from Hartree-Fock to Density Functional Theory.

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