• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 186
  • 59
  • 34
  • 24
  • 20
  • 17
  • 8
  • 8
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 2
  • Tagged with
  • 439
  • 439
  • 60
  • 56
  • 56
  • 53
  • 52
  • 45
  • 38
  • 35
  • 35
  • 34
  • 31
  • 31
  • 30
  • 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.
141

O ensino de progressão geométrica de segunda ordem no ensino médio / The teaching of geometric progression of second order in high school

Lopes, Fernando Henrique [UNESP] 28 August 2017 (has links)
Submitted by FERNANDO HENRIQUE LOPES null (prof.fernandohenrique@hotmail.com) on 2017-09-26T12:07:17Z No. of bitstreams: 1 Dissertação FINAL.pdf: 738423 bytes, checksum: 268542ff74b4d1d629da8bc04263c740 (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-28T12:36:50Z (GMT) No. of bitstreams: 1 lopes_fh_me_sjrp.pdf: 738423 bytes, checksum: 268542ff74b4d1d629da8bc04263c740 (MD5) / Made available in DSpace on 2017-09-28T12:36:50Z (GMT). No. of bitstreams: 1 lopes_fh_me_sjrp.pdf: 738423 bytes, checksum: 268542ff74b4d1d629da8bc04263c740 (MD5) Previous issue date: 2017-08-28 / O presente trabalho tem como objetivo principal apresentar a definição e propriedades de progressões geométricas de 2º grau, geralmente não trabalhadas no estudo de sequências numéricas, que é iniciado no 1º Ano do Ensino Médio. Para isto, é realizado um estudo de casos gerais para sequências e séries de números reais, para posteriormente, exibir aplicações do conceito no Ensino Médio. Inicialmente é apresentado ao aluno as definições e propriedades de sequências e séries, que requer um estudo mais aprofundado uma vez que é um assunto de maior complexidade para aplicação em turmas de ensino médio. Tais propriedades são utilizadas como ferramentas para o desenvolvimento posterior de progressões aritméticas e geométricas, tanto de 1ª como de 2ª ordem. Uma vez definidas as progressões, atividades sobre o assunto são aplicadas aos alunos para que os mesmos dissertem sobre suas facilidades e dificuldades encontradas na resolução. / The present work has as main objective to present the definition and properties of geometric progressions of 2nd degree, usually not worked in the study of numerical sequences, that is initiated in the 1st Year of High School. For this, a study of general cases for sequences and series of real numbers is carried out, later, to show applications of the concept in High School. Initially the definitions and properties of sequences and series are presented to the student, which requires a more in-depth study since it is a subject of greater complexity for application in high school classes. These properties are used as tools for the later development of arithmetic and geometric progressions, both 1st and 2nd order. Once the progressions are defined, activities on the subject are applied to the students so that they tell about their facilities and difficulties found in the resolution.
142

Verificações da punção e da estabilidade global em edifícios de concreto: desenvolvimento e aplicação de recomendações normativas / Punching shear and global stability of concrete buildings: development and application of code provisions

Juliana Soares Lima 20 April 2001 (has links)
Neste trabalho, são estudas as verificações da punção global segundo a revisão da NBR 6118. A partir da análise dos fenômenos físicos e com base nos estudos teóricos realizados, são feitas sugestões para serem contornadas algumas omissões da Norma. Também são propostas complementação que facilitem o entendimento das novas recomendações e, ainda, modificações que melhorem seus resultados. Sugerem-se métodos simplificados relacionados à punção excêntrica, e propõem-se algumas alterações quanto ao uso do &#947z como coeficiente majorador na avaliação da estabilidade global. Observa-se que as verificações, apesar de mais trabalhosas, apresentam melhorias significativas em relação à NBR 6118 (1978), mostrando-se mais detalhadas e eficientes. Ainda assim, considera-se importante a introdução de algumas complementações, como aquelas sugeridas neste trabalho. / This work presents an overview of the requirements for punching shear and global stability of buildings in the draft Brazilian Code for concrete structures. Suggestions are made for fulfilling some omissions of the Code, based on theoretical studies and physical phenomena analysis. Some complements and changes are also proposed to facilitate the understanding of the new recommendations and to improve their results. Simplified methods related to the eccentric punching and modifications in the use of &#947z as a first order effects magnifier are suggested. It is concluded that the new provisions are more detailed and efficient, presenting significant improvements on both topics, especially when compared to NBR 6118 (1978). Nevertheless, it is considered important the introduction of some complements, as those suggested in this work.
143

Linear degeneracy in multidimensions

Moss, Jonathan January 2016 (has links)
Linear degeneracy of a PDE is a concept that is related to a number of interesting geometric constructions. We first take a quadratic line complex, which is a three parameter family of lines in projective space P3 specified by a single quadratic relation in the Plucker coordinates. This complex supplies us with a conformal structure in P3. With this conformal structure, we associate a three-dimensional second order quasilinear wave equation. We show that any PDE arising in this way is linearly degenerate, furthermore, any linearly degenerate PDE can be obtained by this construction. We classify Segre types of quadratic complexes for which the structure is conformally flat, as well as Segre types for which the corresponding PDE is integrable. These results were published in [1]. We then introduce the notion of characteristic integrals, discuss characteristic integrals in 3D and show that, for certain classes of second-order linearly degenerate dispersionless integrable PDEs, the corresponding characteristic integrals are parameterised by points on the Veronese variety. These results were published in [2].
144

Solutions to the equivalent mutants problem : A systematic review and comparative experiment

Orzeszyna, Wojciech January 2011 (has links)
Context: Mutation testing is a fault-based technique for measuring the effectiveness of a test set in terms of its ability to detect faults. Mutation testing seeds artificial faults into an application and checks whether a test suite can detect them. If these faults are not found, the test suite is still not considered to be 'good enough'. However, there are also mutations which keep the program semantics unchanged and thus cannot be detected by any test suite. Finding a way to assess these mutations is also known as the equivalent mutant problem (EMP). Objectives: The main objective of this thesis is to conduct a systematic literature review in the field of mutation testing, to identify and classify existing methods for equivalent mutants detection. In addiction, other objectives are: analyze possibilities to improve existing methods for equivalent mutant detection, implement new or improved method and compare it with existing ones. Methods: Based on the systematic literature review method we have went over publications from six electronic databases and one conference proceedings. Standard method was extended by scanning lists of references and some alternative sources: searching in Google Scholar, checking personal websites of relevant authors and contacting all of them. We have performed all the systematic literature review steps such as the protocol development, initial selection, final selection, quality assessment, data extraction and data synthesis. In the second part of this thesis - an experiment, we have implemented four second order mutation testing strategies and compared them each other from four different perspectives: mutants reduction, equivalent mutants reduction, fault detection loss and mutation testing process time reduction. Results: The search identified 17 relevant techniques in 22 articles. Three categories of techniques can be distinguished: detecting (DEM), suggesting (SEM) and avoiding equivalent mutants generation (AEMG). Furthermore, for each technique current state of development and some ideas on how to improve it are provided. The experiment proved that DifferentOperators strategy gives the best results in all four investigated areas. In addition, time for manual mutants classification against equivalence was measured. Assessing one first order mutant takes 11 minutes 49 seconds, while for the second order mutants classification time is 9 minutes 36 seconds in average. Conclusions: After three decades of studies, results obtained for techniques from the DEM group are still far from perfection (best one is detecting 47,63% of equivalent mutants). Thus, new paths for the solution have been developed - SEM and AEMG group. Methods from both categories help in dealing with EMP, however from SEM provide only mutants likely to equivalent, while from AEMG cause some loss of test effectiveness. The conclusion from the experiment is that DifferentOperators strategy gives the best results among all proposed.
145

Politisk gestaltning av Europaparlamentsvalet i svenska dagstidningar

Andreas, Andersson Kurdve January 2017 (has links)
Uppsatsens syfte är att undersöka hur den politiska gestaltningen i de svenska dagstidningarna Dagens Nyheter och Svenska Dagbladet skiljer sig åt under olika tidsperioder och därmed vid de olika valen; Europaparlamentsvalet samt Svenskt Riksdagsval. Uppsatsen utgår från teorier om andrahandsval och vad det innebär samt teorier om mediegestaltning av politik och vilken roll det kan ha. Uppsatsen jämför Europaparlamentsvalet 2014 med Svenska Riksdagsvalet 2014 för att belysa skillnaderna mellan de två valen samt hur de gestaltas i nämnda dagstidningar. Vidare belyses läsaren om hur Europaparlamentsvalet har förändrats över tid genom en undersökning av perioden år 2003-2004 i syftet att uppmärksamma hur Europaparlamentsvalet som ägde rum år 2004 gestaltades och tolkades av samma svenska dagstidningar då som vid senare tidsperiod. Uppsatsen avslutar i att diskutera resultatet och gör försök att förklara Europaparlamentsvalet position idag samt i framtiden utifrån den empiri och de teorier om andrahandsval som uppsatsen utgick från.
146

Investigation of the response of groups of wave energy devices

Bellew, Sarah Louise January 2011 (has links)
Placing wave energy devices within close proximity to each other can be beneficial as the costs of deployment, maintenance and infrastructure are reduced significantly compared to if the devices are deployed in isolation. A mathematical model is presented in this thesis which combines linear wave theory with a series of linear driven harmonic oscillators to model an array (group) of floating wave energy devices which move predominantly in heave (vertically) in a train of incident regular waves. Whilst similar mathematical models have been used previously to investigate interactions between fluids and groups of structures, much of the published work does not address array configurations or device constraints that are relevant to designers of structure-supported array devices. The suitability of linear theory for application to closely spaced arrays is assessed in this thesis through comparison to small-scale experimental data and by evaluation of the magnitude of second-order hydrodynamic forces. Values of mechanical damping and mass are determined for each element of an array in order to achieve the maximum power from an array of floats without requiring the knowledge of the motion of every float within the array in order to apply the forces to any one float. Further to this, the analysis of floats of varying geometry is performed in order to assess the possibility of array optimisation through the variation of float geometries within a closely spaced array.It is shown in this thesis that linear theory provides a reasonable prediction of the response of floats that are sufficiently close together to interact for most wave frequencies to which the arrays are likely to be subjected. Under the assumption of easily implementable mechanical damping, it is determined that the power output from an array of floats of equal geometry can be increased by specifying different magnitudes of mechanical damping on each float independently of the radiation damping. Variations in submerged float geometries for the purpose of manipulating array characteristics according to the incident wave frequency are best applied through the variation in draft of a single geometry. Variations in submerged float geometry which occur close to the free surface are found to be of the greatest significance. Where the float is uniform in cross-section, the most appropriate method to select float drafts within an array is found to be based on the evaluation of the total damping on each float.
147

Convex relaxations in nonconvex and applied optimization

Chen, Jieqiu 01 July 2010 (has links)
Traditionally, linear programming (LP) has been used to construct convex relaxations in the context of branch and bound for determining global optimal solutions to nonconvex optimization problems. As second-order cone programming (SOCP) and semidefinite programming (SDP) become better understood by optimization researchers, they become alternative choices for obtaining convex relaxations and producing bounds on the optimal values. In this thesis, we study the use of these convex optimization tools in constructing strong relaxations for several nonconvex problems, including 0-1 integer programming, nonconvex box-constrained quadratic programming (BoxQP), and general quadratic programming (QP). We first study a SOCP relaxation for 0-1 integer programs and a sequential relaxation technique based on this SOCP relaxation. We present desirable properties of this SOCP relaxation, for example, this relaxation cuts off all fractional extreme points of the regular LP relaxation. We further prove that the sequential relaxation technique generates the convex hull of 0-1 solutions asymptotically. We next explore nonconvex quadratic programming. We propose a SDP relaxation for BoxQP based on relaxing the first- and second-order KKT conditions, where the difficulty and contribution lie in relaxing the second-order KKT condition. We show that, although the relaxation we obtain this way is equivalent to an existing SDP relaxation at the root node, it is significantly stronger on the children nodes in a branch-and-bound setting. New advance in optimization theory allows one to express QP as optimizing a linear function over the convex cone of completely positive matrices subject to linear constraints, referred to as completely positive programming (CPP). CPP naturally admits strong semidefinite relaxations. We incorporate the first-order KKT conditions of QP into the constraints of QP, and then pose it in the form of CPP to obtain a strong relaxation. We employ the resulting SDP relaxation inside a finite branch-and-bound algorithm to solve the QP. Comparison of our algorithm with commercial global solvers shows potential as well as room for improvement. The remainder is devoted to new techniques for solving a class of large-scale linear programming problems. First order methods, although not as fast as second-order methods, are extremely memory efficient. We develop a first-order method based on Nesterov's smoothing technique and demonstrate the effectiveness of our method on two machine learning problems.
148

Att lova eller inte lova väljarna - det är EU-frågan : En jämförande studie av de svenska riksdagspartiernas vallöften inför Europaparlamentsvalen 2014 och 2019

Carlson, Ester January 2021 (has links)
The European Parliament elections have for decades been described as 'second-order national elections', meaning that parties tend to have a national focus rather than a European one. Furthermore, the parties are often described as a weak link between the European Union and its citizens. Studies on the parties' election promises have mainly been done on national elections and show that election promises become increasingly important over time. However, no previous studies have looked at election promises in European elections. The purpose of this comparative case study is to compare the election promises that Swedish parliamentary parties present in their election manifestos for the European Parliament elections of 2014 and 2019, in order to contribute to both the discourse on European Parliament elections and the discourse on election promises. Two established fields of research that have not previously met in this way. Based on previous research, this study tests eight hypotheses on the material. By mapping and analyzing 1374 election promises from 16 election manifestos, the result shows a predominant share of election promises with a European focus, rather than national. The election promises are surprisingly specific rather than vague and mainly critical of EU-policy rather than the European Union as a political system. The conclusion of this result is that the European Parliament elections as 'second-order national elections' do not emerge when election promises are studied. The results of this study has shown that there is reason to revise the prevailing picture of European Parliament elections in this field of research.
149

Tunable C Band Coupled-C BPF with Resonators Using Active Capacitor and Inductor

Wang, Yu 01 September 2016 (has links)
No description available.
150

A Dirichlet-Dirichlet DD-pre-conditioner for p-FEM

Beuchler, Sven 31 August 2006 (has links)
In this paper, a uniformly elliptic second order boundary value problem in 2D is discretized by the p-version of the finite element method. An inexact Dirichlet-Dirichlet domain decomposition pre-conditioner for the system of linear algebraic equations is investigated. The solver for the problem in the sub-domains and a pre-conditioner for the Schur-complement are proposed as ingredients for the inexact DD-pre-conditioner. Finally, several numerical experiments are given.

Page generated in 0.0712 seconds