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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.
331

The Performance Effects of Latent Factors on Assimilation of Commercial Open-Source ERP Software on Small-Medium Enterprises

Cereola, Sandra 22 September 2008 (has links)
This study tests a theoretical model developed to investigate the impact of assimilation of commercial open source enterprise resource planning software (COSES) in small and medium sized enterprises (SMEs). Specifically, the model explains how the top management team’s (TMT’s) information technology (IT) knowledge and experience impact both assimilation and firm performance. The hypotheses were tested using survey data from SMEs that have implemented COSES. Results from structural equation modeling suggest that SMEs benefit, through higher levels of assimilation and performance, from adopting innovative enterprise resource planning (ERP) systems such as COSES when they have a TMT that has experience with and is knowledgeable about technology. The study also highlights the importance of the TMT in facilitating IT assimilation.
332

Recherche de nouvelles résonances se désintégrant en paires de quarks top avec le détecteur ATLAS du LHC / Search of new resonances decaying into top quark pairs with the ATLAS detector at the LHC and jet calibration studies

Camacho Toro, Reina Coromoto 13 July 2012 (has links)
(...) Le travail de recherche exposé dans cette thèse a été réalisé en utilisant les données collectées par le détecteur ATLAS auprès du LHC. Le LHC est l'accélérateur de particules le plus grand et le plus puissant jamais construit. Il est constitué d'un double anneau de stockage de protons. Environ 10000 physiciens et ingénieurs du monde entier participent à cette expérience en développant de nouvelles techniques et approches pour identifier les événements intéressants cachés dans l'environnement complexe produit dans des collisions proton-proton. Les premières collisions proton-proton ont eu lieu à la fin de l'année 2009 à une énergie de 900~GeV dans le système du centre de masse. Le 19 Mars 2010, le LHC a battu un record en augmentant l'énergie des faisceaux à 3.5 TeV, et les premières collisions à 7 TeV ont été enregistrées le 30 Mars 2010. L'énergie par faisceau pour l'ensemble de 2011 était de 3.5 TeV, et 4 TeV en 2012. Un an d'arrêt technique est prévu en 2013 avant de parvenir à l'énergie nominale de collision de 14 TeV. Quatre expériences se partagent les quatre points de croisement des faisceaux du grand anneau du LHC. Une d'entre elles, ATLAS, est un détecteur généraliste avec un vaste programme de physique. ATLAS est constitué d'un détecteur interne de traces dans un champ magnétique de 2 T, offrant une couverture jusqu'à |η|<2.5, un système calorimétrique allant jusqu'à |η|<4.9, un spectromètre à muons dans un champ magnétique toroïdal et un système de déclenchement composé de trois niveaux. Tous les sous-systèmes ont d'excellentes performances en termes d'efficacité et de résolution. Cette thèse comprend trois travaux interconnectés. En premier lieu, elle décrit les résultats de la recherche de nouvelles résonances qui se désintègrent en paires tt en utilisant les premiers 2.05 fb-1 de données collectées par le détecteur ATLAS en 2011. Dans une deuxième partie, en connection avec cette recherche, des études de performance de Jet Vertex Fraction (JVF) en utilisant des événements tt sont également présentées. JVF est une variable qui peut être utilisée pour réduire les effets d'empilement afin d'améliorer la précision et la sensibilité des analyses de physique à haute luminosité. Finalement, les performances de la calibration Globale Séquentielle des jets, sa validation sur des données réelles et l'évaluation de l'incertitude systématique qui lui est associée seront aussi discutées. La détermination précise de l'échelle en énergie des jets (JES: acronyme de Jet Energy Scale) ainsi que l'obtention d'une résolution optimale sont extrêmement importantes pour de nombreuses analyses de physique au LHC. Cela est vrai en particulier pour la recherche de nouvelles résonances tt en raison de la présence de jets dans l'état final. Les résultats sont présentés dans l'ordre dans lequel ils ont été réalisés au cours de cette thèse. (...) / (...) The studies presented in this thesis were performed using data collected by the ATLAS detector at the LHC. The LHC is the largest and highest energy particle accelerator ever built. Around 10000 physicists and engineers around the world are taking part in this experience by developing new techniques and approaches to identify the interesting physics buried in the complex environment produced in the LHC pp collisions. The LHC produced its first pp collisions on November 23, 2009 at the injection energy of 450 GeV. On March 19, 2010 the LHC broke a record by raising the beam energy to 3.5 TeV, and the first pp collisions at 7 TeV were recorded on March 30, 2010. The beam energy for the whole 2011 year was 3.5 TeV per beam, while in 2012 the beam energy is 4 TeV. At the beginning of 2013 the LHC will go into a long shutdown to prepare for higher energy collisions starting in 2014. At the four collision points of the LHC, detectors have been placed to study the high-energy collisions. One of these detectors, ATLAS, a general purpose detector with an extensive initial physics program. The ATLAS detector consists of a tracking system in a 2 T solenoid field, providing coverage up to a pseudo-rapidity of |η|<2.5, sampling electromagnetic and hadronic calorimeters up to |η|<4.9, muon chambers in a toroidal magnetic field and a trigger system consisting of three levels of event selection. So far, the ATLAS sub-detectors have shown an excellent performance in terms of efficiency and resolution. This thesis contains three different analyses interconnected. The main one concerns the results of the search for new resonances that decay to top-quark pairs using the first 2.05 fb-1 of data collected by the ATLAS detector in 2011. Secondly and related to this search, performance studies of the Jet Vertex Fraction (JVF) in top-quark pairs topologies are presented too. JVF is a variable that can be used to reduce the pile-up effects to improve the precision and sensitivity of physics analyses at high luminosities. Finally, results regarding the performance, validation in data and associated systematic uncertainty derivation of the Global Sequential (GS) jet calibration are discussed. The determination of the jet energy scale and the achievement of the optimal jet performance is of key importance to many LHC physics analyses, specially to the main analysis of this thesis due to the presence of jets in the final state. The results are presented in order that they were performed during the thesis.
333

Charakteristika herních kombinací vrcholných družstev žen na Mistrovství světa 2010 ve volejbalu / The feature of playing combinations of the national team of women played the Word championship in 2010 volleyball

Jindrová, Veronika January 2011 (has links)
Name: The feature of playing combinations of the national team of women played the Word championship in 2010 in volleyball. Subject: The feature of vollejball, the top volleyball, the feature of players and the feature of the whole Word championship in 2010 in volleyball of women. The goal of work: To describe a feature of playing combinations of the top women teams played in the Word championship in 2010 in Japan. To value striking combinations out of the kinds of variatious, how often the strike was applied, and Access of striking. Results: After meeting the goals to auclyse the most used Leeds of strikes combinations. To express the succsess of playing combinations of the top teams including the Czech team. Key words: volleyball, the top volleyball, playing combinations, word championship
334

Charakteristika hry vrcholových družstev žen na MS 2010 ve volejbalu / The characteristic of the games of top women's teams at the vollejball World Cup 2010

Šimková, Adéla January 2011 (has links)
6 ABSTRAKT 1. NAME The characteristic of the games of top women's teams at the volleyball World Cup 2010 2. SUBJECT The characteristic of vollejball, The feature of women's teams at the volleyball World Cup 2010 3. THE GOAL OF WORK Characteristics performance of the game selected volleyball team women's at the World Cup 2010 in Japan, based on the success of the selected gaming activities of individuals. 4. RESULTS After meeting the goals to characterize and compare the results of selected teams, a success in selected gaming activities of the individual. 5. KEY WORDS volleyball, the top volleyball, individual playing activities, World Championships,
335

Investigation of antennas and energy harvesting methods for use with a UHF microtransceiver in a biosensor network

Hodges, Amelia Lynn January 1900 (has links)
Master of Science / Department of Electrical and Computer Engineering / William B. Kuhn / This work was a part of NASA EPSCoR Project NNX11AM05A: Biosensor Networks and Telecommunication Subsystems for Long Duration Missions, EVA Suits, and Robotic Precursor Scout Missions. The project’s main goal is the development of a wireless sensor network inside an astronaut’s spacesuit. Antennas are essential components in a wireless network. Since this antenna will be used inside the spacesuit it is important to consider both the physical size limitations and the desired antenna polarization. After exploring the WWVB radio station antenna which provides the preferred vertical polarization and has a suitable aspect ratio, the top hat antenna seemed promising for intrasuit communication. The design of a top hat antenna is outlined. Then, the antennas were tested using 433 MHz radios in a full scale model spacesuit. This spacesuit was designed specifically to model the behavior of aluminized mylar in the real suit. Test results support the feasibility of an intrasuit wireless network. If a gateway radio is placed on the chest or back, a sensor could be placed anywhere on the body and provide an adequate signal. These initial tests did not include a matching network, but the additional link-margin afforded by a matching network, even an imperfect match, is considered. Energy harvesting is explored as an alternative to batteries powering the intrasuit radio. In the oxygen rich environment of a spacesuit, even the smallest spark can be catastrophic. A variety of energy harvesting options are explored with a focus on thermal energy harvesting. The temperature difference between the human skin and the astronaut’s Liquid Cooling and Ventilation Garment can be used to produce a small voltage. To increase the voltage a step-up converter is implemented. Final integration of the two systems with a biosensor is left for on-going work in the three year NASA project.
336

Využití IPTV v univerzitní síti / IPTV use in academic network

Jireš, Kamil January 2009 (has links)
The purpose of this diploma thesis is to provide readers the deployment of IPTV solutions using free software. In this thesis the reader will familiarize with the theory of IPTV, which implies a necessary part of the system, IPTV related protocols and possible errors that can be when running the IPTV service. The work is divided into four parts. The first part discusses the theory. In theory, the reader familiarize with the definition of basic concepts, which are essential elements of the system, the protocols used in conjunction with IPTV and will also be discussed errors that may occur during operation of IPTV services. The second section outlines the architecture of which the reader can find a solution that was implemented in an experimental operation. The third section focuses on the choice of components (hardware and software) that were used in the test sytem. The variants are mentioned, from which the components were selected. The fourth section contains the actual implementation, which describes each components. At the end of the fourth part is inserted configuration files that can be used in case of repeated implementation of the solution.
337

Measuring Immersion and Enjoyment in a 2D Top-Down Game by Replacing the Mouse Input with Eye Tracking

Fransson, Jonatan, Hiiriskoski, Teemu January 2019 (has links)
Background. Eye tracking has been evaluated and tried in different 2D settings for research purposes. Most commercial games that are using eye tracking use it as an assistive extra input method and are focused around third or first person. There are few 2D games developed with eye tracking as an input method. This thesis aims to test the use of eye tracking as a replacement input method with a chosen set of mechanics for the purpose of playing a 2D top-down game with eye tracking as the main input method. Objectives. To test eye tracking in a 2D top-down game and use it as a replacement input method for the mouse in a novel effort to evaluate immersion and enjoyment. Method. To conduct this study the Tobii 4C eye tracker is used as the replacement peripheral in a 2D game prototype developed for the study. The game prototype is developed with the Unity game engine which the participants played through twice with a different input mode each time. Once with a keyboard and mouse and a second time with a keyboard and an eye tracker. The participants played different modes in alternating order to not sway the results. For the game prototype three different mechanics were implemented, to aim, search for hidden items and remove shadows. To measure immersion and enjoyment an experiment was carried out in a controlled manner, letting participants play through the game prototype and evaluating their experience. To evaluate the experience the participants answered a questionnaire with 12 questions relating to their perceived immersion and a small interview with 5 questions about their experience and perceived enjoyment. The study had a total of 12 participants. Results. The results from the data collected through the experiment indicate that the participants enjoyed and felt more involvement in the game, 10 out of 12 participants answering that they felt more involved with the game using eye tracking compared to the mouse. Analyzing the interviews, the participants stated that eye tracking made the game more difficult and less natural to control compared to the mouse. There is a potential problem that might sway the results toward eye tracking, most participants stated that eye tracking is a new experience and none of the participants had used it to play video games before. Conclusions. The results from the questionnaire prove the hypothesis with statistics, with a p-value of 0.02 &lt; 5% for both increased involvement and enjoyment using eye tracking. Although the result might be biased due to the participant's inexperience with eye tracking in video games. Most of the participants reacted positively towards eye tracking with the most common reason being that it was a new experience to them.
338

Kognitiv kontroll, självreglering och impulsivitet / Cognitive control, self-regulation and impulsivity

Hammarberg, Maxine January 2019 (has links)
Kognitiv kontroll är förmågan att flexibelt anpassa sitt beteende till en eller flera specifika inre motiverande handlingar. Kognitiv kontroll möjliggör denna fokusering för de krav som informationsprocessen kräver. Kognitiv kontroll samt självreglering handlar bland annat om en så kallad top-down informationsprocess i ett globalt neuralt nätverk som pågår i den mänskliga hjärnan. Vi människor utövar denna kognitiva kontroll varje dag i vårat vardagliga liv utan vidare reflektioner. Detta sker genom flera informationsprocesser samtidigt och det är därför svårt att finna en enhetlig integrerad förklaring till de underliggande neurala mekanismerna. Syftet med arbetet är att förklara vad kognitiv kontroll, självreglering och impulsivitet innebär. Kopplingen mellan dessa två kognitiva kapaciteter föreskrivs i denna uppsats gällande de neurala mekanismerna och även kopplingen mellan kognitiv kontroll och självreglering i form av prestationer av både kontrollerade experiment och det vardagliga livet. Medan impulsivitet kopplat till kognitiv kontroll och självreglering är konsekvensen av när de neurala och kognitiva processerna brister i någon mening. Studier relaterat till kognitiv kontroll, inhibering och impulsbeteende använder sig bland annat av functional magnetic resonance imaging (fMRI) för att studera och undersöka detta kognitiva fenomen. Idag beskrivs impulsivitet samt bristande kontroll möjligen som ett maladaptivt beteende med hjälp av bland annat fMRI. Ytterligare fMRI studier har även visat på att kognitiv kontroll samt bristande kognitiv kontroll möjligen kan handla om en minskad eller ökad aktivering i nucleus accumbens, insulan och anterior cingulate cortex (ACC). Forskare inom ämnet har försökt att grundligt undersöka detta neurala nätverk genom flera olika perspektiv och därav presenterar uppsatsen några olika exempel av dessa ingångar för att möjliggöra ett brett perspektiv av denna komplexa mentala kapacitet. Resultaten inom ämnet visar än idag på en komplex multifaciterad natur av de underliggande neurala korrelaten.
339

The Gladiators of the OMXSPI : What are the key drivers trailing the durable performance?

Cullhed, Jakob, Olsson, Fredrik January 2019 (has links)
Background and problem: The impact on the stock market of macroeconomic factors have been analyzed in several earlier studies. These are forces constantly changing and thereby they contribute to changing the supply and demand of stocks. The fact that macroeconomic variables have affected the top performing stocks of the OMXSPI during 2004 – 2018, in terms of performance, plays an important part of the study. Different authors have recognized different factors to affect the stock price development and there has not yet been established an explanation of the determinants of stock prices. Purpose: The purpose of the study was to identify the stocks that continuously have had a development superior to the OMXSPI, and therefore have contributed the most to the development of the OMXSPI during 2004 – 2018. Moreover, the study analyzes the drivers that have contributed to the performance of these stocks. Furthermore, the study clarifies which factors that have contributed to the development of the P/E and the EV/EBITDA of the top performers. Methodology: The study followed a quantitative and deductive approach. The Swedish stock market was analyzed with a focus on the OMXSPI were the top performing stocks of this index were identified through a screening process. Moreover, the top performers were put against the OMXSPI in different time periods to compare the performance. Furthermore, multiples of these top performers and the sectors which they trade in were calculated in order to compare the multiples to each other, with the purpose of analyzing them relative to each other in different time periods. Conclusion: From the findings it could be established very similar patterns between the top performers and the OMXSPI. The difference mainly being that the top performers in every sequence experienced a superior development than the OMXSPI, but also greater declines during short sequences. Moreover, the tables displayed remarkable returns of the top performers and the aggregated top performers traded at premium levels in all analyzed time periods.
340

La spectrométrie de masse haute résolution : application à la FT-ICR bidimensionnelle et à la protéomique dans les domaines de l’archéologie et la paléontologie / High Resolution Mass Spectrometry : Application to Two-Dimensional FT-ICR and Proteomics in the Fields of Archeology and Paleontology

Bray, Fabrice 12 December 2017 (has links)
La spectrométrie de masse est une méthode d’analyse qui permet de travailler sur une large gamme d’échantillons. Elle est utilisée dans de nombreux domaines de recherche comme la chimie analytique, la protéomique, la lipidomique et la métabolomique…Dans un premier temps, mon travail s’est focalisé sur le développement d’une méthode indépendante d’analyse de données par spectrométrie de masse à transformée de Fourier bidimensionnelle. Pour augmenter la résolution en première dimension, une analyse FT-ICR 2D avec un échantillonnage non uniforme (NUS) a été développée. L’augmentation de la résolution dans la première dimension a permis l’obtention d’une haute résolution pour les ions précurseurs. La FT-ICR 2D a été utilisée avec succès pour l’analyse de triacylglycérols contenus dans du plasma mais aussi pour l’analyse d’échantillons archéologiques.Dans un second temps, une stratégie protéomique conjointe bottom-up et top-down a été appliquée à l’analyse d’échantillons archéologiques et paléontologiques à partir d’ossements ou de céramiques. Le développement d’une méthodologie bottom-up, a permis à partir d’ossements archéologiques d’espèces inconnues l’identification des protéines et leurs modifications chimiques. Cet ossement a pu être attribué comme appartenant à l’espèce Homo sapiens. Une analyse top-down a été utilisée pour l’analyse d’échantillons archéologiques. Pour la première fois, une protéine (la caséine de lait) a été identifiée dans un échantillon archéologique d’amphore de l’époque de l’empereur Claude (1er siècle de notre ère) grâce la détection de grands fragments de caséine. / Mass spectrometry is a method of analysis which works on a wide range of sample types. It is used in many research fields such as analytical chemistry, proteomics, lipidomics and metabolomics...Firstly, my work was dedicated to the development of an independent data analysis methodology based on two-dimensional Fourier transform mass spectrometry. For increasing the resolution on the first dimension a 2D FT-ICR analysis with non-uniform sampling was developed. The resolution increase in the first dimension leading to high resolution for the precursor ions. The 2D FT-ICR has been successfully applied for the analysis of triacylglycerol contained on plasma and also for archaeological samples. This methodology led to 2D maps allowing a rapid classification of plants or animals samples.Secondly, a joint bottom-up and top-down proteomics strategy was applied for the analysis of archaeological and paleontological samples from bones or ceramics. The development of a bottom-up methodology, allowed the identification of proteins and their chemical modifications from archeological bones. These bones have been attributed to Homo sapiens. The development of a top-down methodology was applied to the analysis of archaeological ceramic. For the first time, a protein (milk casein) was identified in an archaeological sample of an amphora from Claudius emperor era (1st century A.D) via the detection of large fragments of casein. This first application of the top down proteomics showed that new information can be provided such as the in situ molecular degradation.

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