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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.
531

A distributed analysis and monitoring framework for the compact Muon solenoid experiment and a pedestrian simulation

Karavakis, Edward January 2010 (has links)
The design of a parallel and distributed computing system is a very complicated task. It requires a detailed understanding of the design issues and of the theoretical and practical aspects of their solutions. Firstly, this thesis discusses in detail the major concepts and components required to make parallel and distributed computing a reality. A multithreaded and distributed framework capable of analysing the simulation data produced by a pedestrian simulation software was developed. Secondly, this thesis discusses the origins and fundamentals of Grid computing and the motivations for its use in High Energy Physics. Access to the data produced by the Large Hadron Collider (LHC) has to be provided for more than five thousand scientists all over the world. Users who run analysis jobs on the Grid do not necessarily have expertise in Grid computing. Simple, userfriendly and reliable monitoring of the analysis jobs is one of the key components of the operations of the distributed analysis; reliable monitoring is one of the crucial components of the Worldwide LHC Computing Grid for providing the functionality and performance that is required by the LHC experiments. The CMS Dashboard Task Monitoring and the CMS Dashboard Job Summary monitoring applications were developed to serve the needs of the CMS community.
532

Evaluation of the Effects of Pair Programming on Performance and Social Practices in Distributed Software Development / Evaluation of the Effects of Pair Programming on Performance and Social Practices in Distributed Software Development

Haider, Muhammad Tauqeer, Ali, Imran January 2011 (has links)
Context. Agile methods address the challenges of an unpredictable world by relying on “people and their creativity rather than on processes”, accelerate delivery of software and considered as a reaction to plan-based or traditional methods. Distributed software development helps to access a pool of skilled personnel, completion of tasks around the clock and more. Incorporating of agile methods in distributed software development could help to solve some problems of distributed software development such as lack of communication and its dependencies, close collaboration and so on. Objectives. In this study we investigate the proposed benefits of pair programming, an XP development technique used by agile, and its effects on performance and social practices in distributed software development. Methods. Systematic literature review and an experiment are utilized to fulfill the objectives of this study. In the systematic review a sub-set of the research articles are selected relevant to the subject of this study from the electronic sources including, ACM Digital Library, IEEE, Xplore, EiVillage (Compendx, Inspec), Science Direct and ISI Web of Science. Experiment is conducted to investigate the pair programming effects on performance and social practices. Results. Many proposed benefits of pair programming in existing literature are identified and reported in both collocated and distributed settings. Pair programming is reported as an effective software development technique as well as a pedagogical tool. Experimental results showed that pair programming also effects performance in distributed software development, and positively impacts the social practices (human or social factors). Conclusions. There are many benefits of pair programming reported in collocated settings and less in distributed software development. Pair programming impacts the performance and social practices positively. However, we also conclude that the effective use of pair programming in distributed software development will yield the concrete results as well as the programmers’ pairs should be trained, experienced and well motivated for an effective use of pair programming and to overcome the challenges of distributed software development.
533

Perception of Realistic Flocking Behavior in the Boid Algorithm

Larsson, Max, Lundgren, Sebastian January 2017 (has links)
Context. Simulation of nature is something that is used to immerse the player into the world of games. By adding details in the world such as birds circling in the sky or small fishes swimming in a flock, developers can improve the gaming experience for the user. More precise simulations are something that should be aspired for. This thesis will explore the boid flocking algorithm and evaluate what settings users perceive as realistic behavior for simulating schools of fish. Objectives. This thesis proposes that there should be a set of variables that reflect a more realistic behavior and through gathering data from volunteers and mapping their answers, conclude if that statement is true. Methods. A boid simulation will be run in a number of different scenarios, each differing in variables that are vCohesion, vSeparationand vAmount that make changes to the overall behavior. This behavior is then recorded and compared next to each other in a perceptual experiment with the objective of finding out the preferred settings interms of realism. Results. The experiment showed that the preferred value of vSeperation was around 50 to 60 world units. The value of vCohesion and vAmount was random to what was perceived, so their impact on realism was not significant enough. Conclusions. After running the experiment it was apparent that there was a preferred value on some of the variables that were examined. The larger impact on realism was in the distance each boid wanted to keep from its neighbor, the vision range of each boid defined what was considered a neighborhood. The range on this variable was not of much importance and did not impact what the user perceived as realistic.
534

An Experiment on the Suitability of RAM for Test Case Design

Wu, Hong January 2009 (has links)
To perform software testing at the early stages of software development process can save the cost and effort on finding and fixing defects. As the first stage of software development process, requirements engineering has been moved away from project-initiated requirements engineering towards requirements-initiated development in the last decade. This leads new challenges that it demands support for handling the requirements continually come in from multiple stakeholders on multiple abstraction levels instead of some specific customers. Requirements Abstraction Model was developed as a hierarchical abstraction method for requirements management, which is enable product management to leverage their resources and select requirements for implementation without overloading the organization. RAM was validated in industry on the usability for requirements management, but there is no evaluation for RAM on software testing. This thesis presents an empirical study with a goal of evaluating the suitability of RAM for test case design in respective of efficiency and effectiveness by the comparison with IEEE Std. 830 which is a standard of the traditional requirements specification. For achieving the goal of this study, a controlled experiment is conducted based on the refinement on an initial experiment planning, and is operated with twenty developers in industry in China. Analysis of the collected data from the experiment indicates that RAM has a similar effectiveness as using the requirements in IEEE Std. 830 format, while RAM is more efficient for test case design. Therefore, RAM is suitable for test case design, and has better performance than IEEE Std. 830 comprehensively in view of both efficiency and effectiveness.
535

Etude de la production inclusive de J/ψ dans les collisions pp et Pb-Pb √sNN =5.02 TeV avec le spectromètre à muon de l'expérience ALICE au LHC / Study of the inclusive J/ψ production in pp and Pb-Pb collisions at √sNN = 5.02 TeV with the ALICE muon spectrometer at the LHC

Audurier, Benjamin 05 October 2017 (has links)
La production des états charmonia (par exemple le J/ψ et le ψ(2S)) est l’une des sondes étudiées pour comprendre les propriétés du Plasma de Quarks et de Gluons (PQG) formé dans les collisions d’ions lourds à très haute énergie. En effet, la présence d’un milieu déconfiné est susceptible de modifier le taux de production des charmonia par effet d’écrantage de couleur de la paire de quarks charme-anti-charme. Une telle suppression fut déjà observée dans les collisions d’ions lourds aux énergies du SPS et du RHIC. Dans les collisions Pb-Pb à √sNN = 2.76 TeV au LHC, une suppression relative du taux de production du J/ψ par rapport à celui mesuré dans les collisions pp normalisé aux nombres de collisions binaires proton-proton (facteur de modification nucléaire RAA) fut aussi mesurée. Cette suppression est cependant moins importante que ce qui fut observé à plus petites énergies dans le centre de masse. Ceci peut s’expliquer par la présence d’un nouveau mécanisme de production, la recombinaison de quarks charme et anticharme déconfinés au moment de l’expansion hydrodynamique du PQG ou durant la phase d’hadronisation. Dans cette thèse, nous présentons les résultats de la production de J/ψ dans les collisions pp et Pb-Pb, mesurée par le détecteur ALICE à √sNN = 5.02 TeV à rapidité avant dans le canal de décroissance dimuonique. La section efficace de production mesurée dans les collisions pp est comparée à différents modèles théoriques et est utilisée pour calculer le RAA en collisions Pb-Pb, lui-même comparé à différentes prédictions théoriques ainsi qu’aux précédentes mesures. / The production of charmonium states (for instance J/ψ and ψ(2S)) is one of the probes studied to investigate the properties of the Quark-Gluon Plasma (QGP) formed in high-energy heavy-ion collisions. Indeed, the presence of a deconfined medium should modify the charmonium production yield, due to the color screening of the charm quark anti-quark potential. Such a suppression was already observed in heavy-ion collisions at SPS and RHIC energies. In Pb-Pb collisions at √sNN = 2.76 TeV at the LHC, a clear suppression of the J/ψ yield with respect to the one measured in binary-scaled pp collisions (nuclear modification factor RAA) was observed, but much smaller than that at lower collision energies. This observation can be explained by the presence of a new production mechanism, the (re)combination of deconfined charm and anti-charm quarks during the hydrodynamical expansion of the QGP or at the hadronization stage. In this thesis, we report on the results of the J/ψ production in pp and Pb-Pb collisions measured with the ALICE detector √sNN = 5.02 TeV at forward rapidity in the dimuon channel. The cross-section in pp collisions is compared to various model calculations, and is used to compute the RAA in Pb-Pb collisions, which is also compared to theoretical predictions as well as to previous measurements.
536

PASSWORD PRACTICE : The effect of training on password practice

Ekström, Niklas January 2015 (has links)
There are several concerning issues with passwords today; one of them being weak passwords, but password management also plays a big role e.g. when the users reuses passwords over several services or don't change their passwords on a regular basis. With the usage of passwords for several aspects of our daily lives comes the responsibility of trying to mitigate these issues, a role that often falls on to the users themselves. The usage of guidelines has proved helpful in this regard but still lacks important aspects. This paper suggests the usage of education in the form of a lecture to help with the problem. In this paper we conducted a study of password leaks, a literature analysis of the area around passwords and perform some qualitative interviews with different kinds of people with varying education and usage of passwords. The results from these studies will then lay the foundation for the lecture in the experiment part of the paper, two experiment groups will be used, one given a lecture as education on the matter and one control group not given any education. The study has showed that the usage of a lecture can help increase the entropy, average length of user‟s passwords. These results can be interpreted together with another study that did a similar experiment to that a lecture can be a more efficient way to teach users about passwords.
537

The Effect of Corporate Social Responsibility Investment and Disclosure on Cooperation in Business Collaborations

Farrington, Sukari 11 November 2017 (has links)
I experimentally examine whether disclosure of corporate social responsibility (CSR) investment facilitates cooperation in business collaborations. Business collaborations are essential for firms to maintain their competitive advantage. However, half of all ventures fail. A major reason for this high failure rate is a lack of cooperation among business collaboration partners, known as relational risk. Findings suggest that CSR disclosure leads to greater CSR investment, but does not result in an overall higher level of cooperation. However, CSR disclosure moderates the link between CSR investment and cooperation. When CSR investment is disclosed, cooperation is highest when both managers invest in CSR. Further, managers who invest in CSR are more sensitive to CSR disclosure information than managers who do not invest in CSR. Managers who invest in CSR are more cooperative when they receive a signal their partner also invested in CSR. Managers who do not invest in CSR do not attend to CSR disclosure information and are equally cooperative when partnered with a CSR investor or a non-CSR investor. Finally, when CSR investment is not disclosed, managers who invest in CSR are no more likely to cooperate than managers who do not invest in CSR. Although CSR is widespread, little is known about why managers invest in CSR or disclose CSR information. This study has implications for practitioners and academics on CSR by demonstrating a potential benefit of CSR investment and disclosure, mitigating relational risk in business collaborations.
538

Atletické činnosti v mateřské škole / Atletic Activites in kindergarten

Milasevičová, Michaela January 2015 (has links)
This thesis is focused on the inclusion of athletic activities in kindergarten. It is conceived as a methodical collection of athletic activities that are established for kindergarten teachers. Its aim is to find suitable athletic activities, to create an overview and to practically try them with preschool children. The work is divided into two parts: theoretical and practical. The theoretical part is dedicated to a preschool child in terms of physiological and motor. It also describes the importance of play and movement in this age. Another chapter deals with the Framework educational program for preschool education and its relationship to athletics. Then the chapter about athletics follows, which provides a brief history of athletics and its importance to the child. There are also described physical abilities, which are closely related to athletic activities since their assumption. The last part is about the correct techniques of athletic disciplines that can be implemented in kindergarten and it is running, jumping and throwing. In the practical part there are selected athletic activities and games, which are divided into groups according to disciplines of running, dumping, throwing and combination of all activities. In the final section is recorded according to their evalution of selection and...
539

Právní úprava pokusů na zvířatech / Legislation of animal experiment

Kropíková, Karolína January 2017 (has links)
This diploma thesis analyzes legislation of executing animal experiments and protection of experimental animals. It is divided into five chapters, each of one is focused on specific area of the topic. The first chapter describes legal sources on international, European and state level. The chapter is closed by a subchapter about judicial activity. The second chapter is focused on principles of animal experiments and its two subchapters describe the 3R concept and legal principles of animal experiments. The third chapter concerns theoretical aspects and key concepts of animal experiment. It is divided into four subchapters, which involve the term of animal experiment, welfare, status of living animal in a legal system of Czech Republic and alternatives to animal experiments. Each of this unit is divided into subchapters, which are focused on specific areas. The fourth chapter concerns six subchapters, which describes the authorization for using animals for experiments, persons working with experimental animals, acceptable experiment, experimental animals, project of experiment and executing experiments. Each of this units is divided into subchapters according to focus of each chapter. The last fifth chapter describes delict responsibility and it is divided into two subsections - responsibility in...
540

Automotive Engine Calibration with Experiment-Based Evolutionary Multi-objective Optimization / 実験ベース進化的多目的最適化による自動車用エンジンの適合 / ジッケン ベース シンカテキ タモクテキ サイテキカ ニ ヨル ジドウシャヨウ エンジン ノ テキゴウ

Kaji, Hirotaka 24 September 2008 (has links)
The aim of this thesis is establishment of an overall framework of a novel control parameter optimization of automotive engine. Today, control parameters of an automotive engine have to be adjusted adequately and simultaneously to achieve plural criteria such as environmental emissions, fuel-consumption and engine torque. This process is called 'engine calibration'. Because many electronic control devices have been adopted for engine to satisfy these objectives, the complexity of engine calibration is increasing year to year. Recent progress in automatic control and instrumentation provides a smart environment called Hardware In the Loop Simulation (HILS) for engine calibration. In addition, Response Surface Methodology (RSM) based on statistical model is currently employed as the optimization method. Nevertheless, this approach is complicated by adequate model selection, precise model construction, and close model validation to confirm the precision of the model output. To cope with these problems, we noticed experiment-based optimization via HILS environment based on Multi-objective Evolutionary Algorithms (MOEAs), that is expected to be a powerful optimization framework for real world problems such as engineering design, as another automatic calibration approach. In experiment-based optimization, the parameters of a real system are optimized directly by optimization techniques in real time through experimentation. In this thesis, this approach is called Experiment-Based Evolutionary Multi-objective Optimization (EBEMO) and it is proposed as a novel automatic engine calibration technique. This approach can release us from burdens of model selection, construction, and validation. When using this technique, calibration can be done immediately after specifications have been changed after optimization. Hence, EBEMO promises to be an effective approach to automatic engine calibration. However, since conventional MOEAs face several difficulties, it is not easy to apply it to real engines. On the one hand, deterioration factors of the search performance of MOEAs in real environments have to be considered. For example, the observation noise of sensors included in output interferes with convergence of MOEAs. In addition, transient response by parameter switching also has similar harmful effects. Moreover, the periodicity of control inputs increase the complexity of the problems. On the other hand, the search time of MOEAs in real environments has to reduce because MOEAs require a tremendous number of evaluations. While we can obtain many measurements with HILS, severe limitations in the number of fitness evaluations still exist because the real experiments need real-time evaluations. Therefore, it is difficult to obtain a set of Pareto optimal solutions in practical time with conventional MOEAs. Additionally, plural MOPs defined by plural operating conditions of map-based controllers has to be optimized. In this thesis, to overcome the difficulties and to make EBEMO using the HILS environment feasible, five techniques are proposed. Each technique is developed through problem formulation, and their effectiveness are confirmed via numerical and real engine experiments. First, observation noise handling technique for MOEAs is considered. Because observation noise deteriorates the search ability of MOEAs, a memorybased fitness estimation method to exclude observation noise is introduced. Then, a crossover operator for periodic functions is proposed. Periodicity exists in engineering problems and leads to harmful effects on the performance of evolutionary algorithms. Moreover, the influence of transient response caused by parameter switching for dynamical systems is considered. In order to solve this problem, a solver of traveling salesman problems is used to determine the evaluation order of individuals. In addition, Pre-selection as acceleration method of MOEAs is proposed. In this technique, the generated offspring are pre-evaluated in the approximation model made by the search history, and then the promising offspring are evaluated in a real environment. Finally, parameterization of multi-objective optimization problems is considered. In engine calibration for maps, optimal control parameters have to be obtained at each operating condition such as engine speed and torque. This problem can be formulated in a form that needs to solve all of the plural multi-objective optimization problems defined by plural conditional variables. To solve this problem effectively, an interpolative initialization method is proposed. Through the real engine experiments, it was confirmed that EBEMO can achieve a practical search accuracy and time by using proposed techniques. In conclusion, the contribution of EBEMO for engine calibration is discussed. Additionally, the directions for future work are outlined. / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(情報学) / 甲第14187号 / 情博第320号 / 新制||情||61(附属図書館) / 26493 / UT51-2008-N504 / 京都大学大学院情報学研究科社会情報学専攻 / (主査)教授 喜多 一, 教授 酒井 徹朗, 教授 片井 修 / 学位規則第4条第1項該当

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