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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.
121

Least-squares variance component estimation theory and GPS applications /

Amiri-Simkooei, AliReza, January 2007 (has links)
Originally presented as the author's thesis (doctoral)--Delft University of Technology. / Includes bibliographical references (p. [185]-194) and index.
122

Tests for specification errors in classical linear least squares regression analysis

Ramsey, James Bernard. January 1968 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 140-143).
123

Is it too late baby? pinpointing the emergence of a black-white test score gap in infancy /

Rippeyoung, Phyllis Love Farley. January 2006 (has links)
Thesis (Ph.D.)--University of Iowa, 2006. / Supervisor: Mary Noonan Includes bibliographical references (leaves 170-182).
124

Reconstructing and analyzing surfaces in 3-space

Sun, Jian, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 129-135).
125

Least squares finite element methods for the Stokes and Navier-Stokes equations /

Bochev, Pavel B. January 1994 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 155-158). Also available via the Internet.
126

An analysis of the modeling used to determine customer satisfaction

Patten, Kyle January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Kevin Dhuyvetter / Many companies use surveys to establish customer satisfaction metrics. This OEM has been using surveys to analyze customer satisfaction with their products, services, and distribution channel for several decades. Satisfaction metrics are established for the brand, product, and channel partners. The product metric is derived from a question on the survey asking customers how satisfied they are with the product. There are subsequent questions thereafter inquiring about satisfaction with specific functional areas of the product. It is common practice to use Partial Least Squares (PLS) regression analysis to evaluate what impacts the functional area questions have on the overall satisfaction question. The model results are used to understand what areas of the machine should be focused on to improve customers’ experiences with the machine. These results are compared to other data sources such as warranty, field reports, customer focus groups, etc. The results from these models are sometimes questioned based on what common intuition would suggest. Typically the top three drivers to the product metric are understandable, but there are often one or two key areas that do not make logical sense. The objective of this thesis was to understand whether PLS modeling is appropriate given the nature of customer survey data. Models were estimated using existing survey data on a specific model in the tractor product line. PLS models assume data are linear with no bounds. This in itself likely makes this type of model inappropriate for analyzing customer survey data. Responses are bounded on an 11 point scale from 0-10, however, the PLS model being non-bounded assumes there can be a score under 0 or over 10. The model also assumes a linear slope that would indicate each covariate answer 0-10 has the same level of effect on the response variable. This research has found that each covariate answer is in fact non-linear. For example, a customer answering a 2 to quality of manufacturing workmanship has a different impact on the overall satisfaction score than a customer who answers 8. Finally, this research discovered that the PLS models produce negative coefficients of significant value that are not reported to the enterprise. Binary and ordered logistic (logit) models were estimated as an alternative to PLS. Logistic models are non-linear and are commonly used to evaluate bounded data. Response data were separated into two groups based on Net Promoter Score (NPS) Methodology (Reicheld 2006). Using the NPS methodology, 0-6 scores are considered detractors, 7-8 scores are considered passives, and 9-10 scores are considered promoters. The logistic models demonstrate that the top two drivers to customer satisfaction scores are still quality of manufacturing workmanship and reliability/operational availability (similar to results of the PLS model). The unresolved problems question on the survey was included in the models and demonstrated that the predicted probability of a customer being a promoter is much higher in both binary and ordered logit models if no unresolved problems exist. Finally, the model found engine oil consumption remained negative and is statistically significant suggesting that even with the alternative modeling approach there still may be data issues related to the survey. It is recommended that the OEM implement logistic modeling for analyzing customer survey data. It is also recommended that a new survey design be constructed to eliminate issues with correlated data that can lead to spurious and unexplainable results.
127

Mínimos quadrados aplicados à super-resolução de vídeo

Brandalise, Rodrigo 20 February 2014 (has links)
Neste trabalho é proposta uma adaptação do método de Mínimos Quadrados aplicado à reconstrução de imagens com Super-Resolução, visando a reconstrução de vídeo (sequências de imagens) em tempo real. Resultados demonstram que a implementação proposta pode apresentar um desempenho melhor que o algoritmo de menor custo computacional da literatura, com um pequeno incremento no número de operações. Por fim, a estrutura proposta sugere viabilidade de análise. De posse de um modelo teórico de comportamento, parâmetros ótimos de projeto podem ser obtidos melhorando ainda mais o desempenho do algoritmo. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-02-11T16:26:47Z No. of bitstreams: 1 Dissertacao Rodrigo Brandalise.pdf: 882370 bytes, checksum: f5b09a60e986391a1d064bc07ccb57e6 (MD5) / Made available in DSpace on 2015-02-11T16:26:47Z (GMT). No. of bitstreams: 1 Dissertacao Rodrigo Brandalise.pdf: 882370 bytes, checksum: f5b09a60e986391a1d064bc07ccb57e6 (MD5) / In this work an adaptation of the Least Squares method applied to Super-Resolution image reconstruction is proposed aiming real time video (image sequences) reconstruction. Results demonstrate that the proposed implementation presents a better performance than the algorithm with the lower computational cost presented in the literature, considering a small increase in the number of operations. Finally, the proposed structure suggests feasibility of analysis. A theoretical model for the algorithm behavior can leads to an optimal parameters design yielding further improvements in the algorithm performance.
128

Comparison of Two Vortex-in-cell Schemes Implemented to a Three-dimensional Temporal Mixing Layer

Sadek, Nabel January 2012 (has links)
Numerical simulations are presented for three dimensional viscous incompressible free shear flows. The numerical method is based on solving the vorticity equation using Vortex-In-Cell method. In this method, the vorticity field is discretized into a finite set of Lagrangian elements (particles) and the computational domain is covered by Eulerian mesh. Velocity field is computed on the mesh by solving Poisson equation. The solution proceeds in time by advecting the particles with the flow. Second order Adam-Bashford method is used for time integration. Exchange of information between Lagrangian particles and Eulerian grid is carried out using the M’4 interpolation scheme. The classical inviscid scheme is enhanced to account for stretching and viscous effects. For that matter, two schemes are used. The first one used periodic remeshing of the vortex particles along with fourth order finite difference approximation for the partial derivatives of the stretching and viscous terms. In the second scheme, derivatives are approximated by least squares polynomial. The novelty of this work is signified by using the moving least squares technique within the framework of the Vortex-in-Cell method and implementing it to a three dimensional temporal mixing layer. Comparisons of the mean flow and velocity statistics are made with experimental studies. The results confirm the validity of the present schemes. Both schemes also demonstrate capability to qualitatively capture significant flow scales, and allow gaining physical insight as to the development of instabilities and the formation of three dimensional vortex structures. The two schemes show acceptable low numerical diffusion as well.
129

Optimization of Sampling Structure Conversion Methods for Color Mosaic Displays

Zheng, Xiang January 2014 (has links)
Although many devices can be used to capture images of high resolution, there is still a need to show these images on displays with low resolution. Existing methods of subpixel-based down-sampling are reviewed in this thesis and their limitations are described. A new approach to optimizing sampling structure conversion for color mosaic displays is developed. Full color images are filtered by a set of optimal filters before down-sampling, resulting in better image quality according to the SCIELAB measure, a spatial extension of the CIELAB metric measuring perceptual color difference. The typical RGB stripe display pattern is tested to get the optimal filters using least-squares filter design. The new approach is also implemented on a widely used two-dimensional display pattern, the Pentile RGBG. Clear images are produced and color fringing artifacts are reduced. Quality of down-sampled images are compared using SCIELAB and by visual inspection.
130

Mínimos quadrados aplicados à super-resolução de vídeo

Brandalise, Rodrigo 20 February 2014 (has links)
Neste trabalho é proposta uma adaptação do método de Mínimos Quadrados aplicado à reconstrução de imagens com Super-Resolução, visando a reconstrução de vídeo (sequências de imagens) em tempo real. Resultados demonstram que a implementação proposta pode apresentar um desempenho melhor que o algoritmo de menor custo computacional da literatura, com um pequeno incremento no número de operações. Por fim, a estrutura proposta sugere viabilidade de análise. De posse de um modelo teórico de comportamento, parâmetros ótimos de projeto podem ser obtidos melhorando ainda mais o desempenho do algoritmo. / In this work an adaptation of the Least Squares method applied to Super-Resolution image reconstruction is proposed aiming real time video (image sequences) reconstruction. Results demonstrate that the proposed implementation presents a better performance than the algorithm with the lower computational cost presented in the literature, considering a small increase in the number of operations. Finally, the proposed structure suggests feasibility of analysis. A theoretical model for the algorithm behavior can leads to an optimal parameters design yielding further improvements in the algorithm performance.

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