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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.
301

Clustering Algorithms for Time Series Gene Expression in Microarray Data

Zhang, Guilin 08 1900 (has links)
Clustering techniques are important for gene expression data analysis. However, efficient computational algorithms for clustering time-series data are still lacking. This work documents two improvements on an existing profile-based greedy algorithm for short time-series data; the first one is implementation of a scaling method on the pre-processing of the raw data to handle some extreme cases; the second improvement is modifying the strategy to generate better clusters. Simulation data and real microarray data were used to evaluate these improvements; this approach could efficiently generate more accurate clusters. A new feature-based algorithm was also developed in which steady state value; overshoot, rise time, settling time and peak time are generated by the 2nd order control system for the clustering purpose. This feature-based approach is much faster and more accurate than the existing profile-based algorithm for long time-series data.
302

A Quasi-Experimental Study of Inter-rater Reliability When Awarding Exceptional Quality Points on the Texas Teacher Appraisal Instrument

Dobbs, Louann 08 1900 (has links)
This study investigates the inter-rater reliability of appraisers who award exceptional quality points on the Texas Teacher Appraisal Instrument. Inter-rater reliability was measured when appraisers scored exceptional quality points after viewing a videotaped lesson. Comparisons were made between appraisers when grouped according to elementary or secondary certification, sex, years of administrative experience, and type of training. A total of 707 subjects from 56 school districts participated in the study. Five research hypotheses were formulated with the .05 level of significance for acceptance. All hypotheses were tested by correlation of coefficients, multiple response procedures, frequencies, and percentages. The data measuring inter-rater reliability of the appraisers in training imply that there is very little reliability in the awarding of exceptional quality points on the Texas Teacher Appraisal Instrument. The findings of this study are that certification, sex, administrative experience, and type of training made no significant differences when scoring the instrument. Therefore, it is concluded that the scoring of exceptional quality points is a subjective, professional judgment made by each appraiser when observing a teacher. Since no significant reliability was found, the scoring of exceptional quality points cannot be supported as a reliable means of determining the quality of teaching in Texas schools. Generally, elementary certified appraisers awarded fewer exceptional quality points than secondary appraisers, males awarded slightly more points than females, appraisers indicated no noticeable trend because of years of administrative experience, and less experienced appraisers had the tendency to award more points than experienced appraisers. Therefore, inter-rater reliability in awarding exceptional quality points cannot be expected on a consistent basis. Each appraiser, regardless of certification, sex, years of administrative experience or training, will use his or her own professional judgment when scoring the instrument.
303

Waring-type problems for polynomials : Algebra meets Geometry

Oneto, Alessandro January 2016 (has links)
In the present thesis we analyze different types of additive decompositions of homogeneous polynomials. These problems are usually called Waring-type problems and their story go back to the mid-19th century and, recently, they received the attention of a large community of mathematicians and engineers due to several applications. At the same time, they are related to branches of Commutative Algebra and Algebraic Geometry. The classical Waring problem investigates decompositions of homogeneous polynomials as sums of powers of linear forms. Via Apolarity Theory, the study of these decompositions for a given polynomial F is related to the study of configuration of points apolar to F, namely, configurations of points whose defining ideal is contained in the ``perp'' ideal associated to F. In particular, we analyze which kind of minimal set of points can be apolar to some given polynomial in cases with small degrees and small number of variables. This let us introduce the concept of Waring loci of homogeneous polynomials. From a geometric point of view, questions about additive decompositions of polynomials can be described in terms of secant varieties of projective varieties. In particular, we are interested in the dimensions of such varieties. By using an old result due to Terracini, we can compute these dimensions by looking at the Hilbert series of homogeneous ideal. Hilbert series are very important algebraic invariants associated to homogeneous ideals. In the case of classical Waring problem, we have to look at power ideals, i.e., ideals generated by powers of linear forms. Via Apolarity Theory, their Hilbert series are related to Hilbert series of ideals of fat points, i.e., ideals of configurations of points with some multiplicity. In this thesis, we consider some special configuration of fat points. In general, Hilbert series of ideals of fat points is a very active field of research. We explain how it is related to the famous Fröberg's conjecture about Hilbert series of generic ideals. Moreover, we use Fröberg's conjecture to deduce the dimensions of several secant varieties of particular projective varieties and, then, to deduce results regarding some particular Waring-type problems for polynomials. In this thesis, we mostly work over the complex numbers. However, we also analyze the case of classical Waring decompositions for monomials over the real numbers. In particular, we classify for which monomials the minimal length of a decomposition in sum of powers of linear forms is independent from choosing the ground field as the field of complex or real numbers.
304

Mesure de cohérence stéréoscopique : effet du vieillissement et du microstrabisme

Laframboise, Stéphane January 2006 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
305

Reconstruction interactive de modèles hiérarchiques par sculpture d'espace

Granger-Piché, Martin January 2004 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
306

Statická analýza programů v C# / Static analysis of C# programs

Malý, Petr January 2014 (has links)
The goal of this diploma thesis is to study and implement selected methods of static code analysis for C# programs translated into the Common Intermediate Language. The results of this work are integrated into the ParallaX Development Environment system. This diploma thesis focuses on Structural, Points-to and Dependence. analysis. Powered by TCPDF (www.tcpdf.org)
307

Vznik algických zón na ruce při jízdě na spinningovém kole / The formation of algic zones on hands while riding a spinning bike

Firstová, Kateřina January 2012 (has links)
Title: The formation of algic zones on hands while riding a spinning bike Objectives: The aim of the work is verification of changes of nociception in pre-defined points in the cyclists hands during one hour's spinning lesson. Methods: A total of 13 participants (9 female, 4 male), aged between 20-50 years old, took part in this study. First personal data was collected using a structured questionnaire. Subsequently, the pain threshold in the palms and palmar sides of the fingers of both hands was measured using algometer Algometer type II, from the company Somedic Sales AB. The acquired data was then statistically evaluated and compared by Pearson correlation quotient and analysis of variance ANOVA. A comparison of the pain treshold before and after the spinning lesson, related to gender, dominant and non-dominant hand and the age of participants, was eventually carried out. Results: After an hour of spinning had occured, in all measured points there was a reduction in pain threshold with an average of 12.83%. This change was the same in all of the measured points, which means that there was no overloading of one hand or any group of the points. The statistical evaluation has shown, that the change of the pain threshold is not dependent on the gender of the participants, and it is not statistically...
308

Food safety knowledge and attitudes: investigating the potential benefits of on-site food safety training for folklorama, a temporary food service event

Mancini, Roberto January 1900 (has links)
Master of Science / Department: Diagnostic Medicine/Pathobiology / Douglas Powell / Folklorama in Winnipeg, Manitoba, Canada is a 14-day temporary food service event that explores the many different cultural realms of food, food preparation, and entertainment. The ethnic nature and diversity of foods prepared within each pavilion presents a unique problem for food inspectors as each culture prepares food in their own very unique way. In 2010, the Russian pavilion at Folklorama was implicated in a foodborne outbreak of E.coli O157 causing 37 illnesses and 18 hospitalizations. Both the Department of Health and Folklorama Board of Directors realized a need for implementation of a food safety delivery program that would be more effective than a simple 2-hour food safety course delivered via PowerPoint slides. Until 2011, the 2-hour food safety course delivered to event co-ordinators and food operators for Folklorama pavilions was not mandatory. The course is now mandatory in 2011 for all Folklorama pavilions. Five randomly chosen pavilions were trained on-site, in their work environment, focusing on critical control points specific to their menu. A control group (five pavilions) did not receive on-site food safety training. Critical infractions noted on standardized food inspection reports were assessed. Results of the current study suggest no statistically significant difference in food inspection scores between the trained group and control group. Results imply that the 2-hour food safety course delivered via slides was sufficient to pass public health inspections.
309

Construction of algebraic curves with many rational points over finite fields / Construction of algebraic curves with many rational points over finite fields

Ducet, Virgile 23 September 2013 (has links)
L'étude du nombre de points rationnels d'une courbe définie sur un corps fini se divise naturellement en deux cas : lorsque le genre est petit (typiquement g<=50), et lorsqu'il tend vers l'infini. Nous consacrons une partie de cette thèse à chacun de ces cas. Dans la première partie de notre étude nous expliquons comment calculer l'équation de n'importe quel revêtement abélien d'une courbe définie sur un corps fini. Nous utilisons pour cela la théorie explicite du corps de classe fournie par les extensions de Kummer et d'Artin-Schreier-Witt. Nous détaillons également un algorithme pour la recherche de bonnes courbes, dont l'implémentation fournit de nouveaux records de nombre de points sur les corps finis d'ordres 2 et 3. Nous étudions dans la seconde partie une formule de trace d'opérateurs de Hecke sur des formes modulaires quaternioniques, et montrons que les courbes de Shimura associées forment naturellement des suites récursives de courbes asymptotiquement optimales sur une extension quadratique du corps de base. Nous prouvons également qu'alors la contribution essentielle en points rationnels est fournie par les points supersinguliers. / The study of the number of rational points of a curve defined over a finite field naturally falls into two cases: when the genus is small (typically g<=50), and when it tends to infinity. We devote one part of this thesis to each of these cases. In the first part of our study, we explain how to compute the equation of any abelian covering of a curve defined over a finite field. For this we use explicit class field theory provided by Kummer and Artin-Schreier-Witt extensions. We also detail an algorithm for the search of good curves, whose implementation provides new records of number of points over the finite fields of order 2 and 3. In the second part, we study a trace formula of Hecke operators on quaternionic modular forms, and we show that the associated Shimura curves of the form naturally form recursive sequences of asymptotically optimal curves over a quadratic extension of the base field. Moreover, we then prove that the essential contribution to the rational points is provided by supersingular points.
310

Demand-Driven Static Analysis of Heap-Manipulating Programs

Chenguang Sun (5930306) 16 August 2019 (has links)
<div>Modern Java application frameworks present significant challenges for existing static analysis algorithms. Such challenges include large-scale code bases, heap-carried dependency, and asynchronous control flow caused by message passing.</div><div>Existing analysis algorithms are not suitable to deal with these challenges. One reason is that analyses are typically designed to operate homogeneously on the whole program. This leads to scalability problems when the analysis algorithms are used on applications built as plug-ins of large frameworks, since the framework code is analyzed together with the application code. Moreover, the asynchronous message passing of the actor model adopted by most modern frameworks leads to control flows which are not modeled by existing analyses.</div><div>This thesis presents several techniques for more powerful debugging and program understanding tools based on slicing. In general, slicing-based techniques aim to discover interesting properties of a large program by only reasoning about the relevant part of the program (typically a small amount of code) precisely, abstracting away the behavior of the rest of the program.</div><div>The key contribution of this thesis is a demand-driven framework to enable precise and scalable analyses on programs built on large frameworks. A slicing algorithm, which can handle heap-carried dependence, is used to identify the program elements relevant to an analysis query. We instantiated the framework to infer correlations between registration call sites and callback methods, and resolve asynchronous control flows caused by asynchronous message passing.</div>

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