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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.
61

Production Of Z + Jet And Hf Jet Energy Scale Calibration At 7 Tev In The Cms Experiment At Lhc

Bilin, Bugra 01 September 2011 (has links) (PDF)
Forward Jet Calibration for CMS detector is presented using Z boson + jet event samples in the pseudorapidity region of 0 &lt / |&eta / | &lt / 5. The results are based on proton-proton collision data at center of mass energy of &radic / s = 7 TeV corresponding to &sim / 1 fb&minus / 1 of data. Z bosons are reconstructed from opposite sign lepton pairs (&mu / +&mu / &minus / , e+e&minus / ) and the transverse momentum balance of the Z boson and the associated jet is used to derive the calibration coefficients. The coefficients are tested on jets from a WW Monte Carlo sample using the W-mass constraint. The W mass peak position is observed to be improved by 20 % without loss of resolution.
62

Study Of The Heavy Quarkonia Spectra In The Quark Model

Takan, Taylan 01 February 2012 (has links) (PDF)
Conventional Heavy Quarkonium systems, Charmonium and Bottomonium, are believed to be composed of a heavy quark and anti-quark pair. These systems are investigated by dierent methods resulting from dierent approaches to Quantum Chromodynamics (QCD), such as Lattice QCD, Eective Theories and Sum Rules. In this thesis we study the spectrum of Charmonium and Bottomonium using a non-relativistic Quark Model. Assuming one gluon exchange for the short distances and a linear confining potential for long distances we derive Breit-Fermi interaction Hamiltonian and calculate the spectra arising from this Hamiltonian. Also we calculate the partial widths of E1 and M1 radiative decays.
63

Schnittstelle Spieler

Piehler, Robert 11 June 2008 (has links)
Die Qualität der Schnittstelle eines Videospiels kann wesentlich zu dessen kommerziellen Erfolg beitragen. Dennoch beschränkt sich die entsprechende Evaluation primär auf die Auswertung qualitativer Daten, die etwa in Nutzertests erhoben werden. Inferenzstatistische Verfahren kommen bisher mangels theoretischer Grundlagen kaum zum Einsatz. Die vorliegende Arbeit stellt daher ein theoretisches Framework zur quantitativen Analyse verschiedener Dimensionen der Schnittstellengestaltung in Videospielen zur Verfügung. Dabei wird ausgehend von spielwissenschaftlichen Überlegungen und einer Erweiterung von Huizingas Konzept des „magic circle“ ein Bogen von perzeptiven, psychologischen und soziologischen bis hin zu kulturellen Aspekten gespannt. Methodisch handhabbar wird dieses Konstrukt durch eine Ausrichtung am Genre-Begriff, der für den Bereich der Videospiele diskutiert wird. So entsteht ein ganzheitliches Modell, das den Grundstein zu einem zielgruppenspezifischen und quantitativen Messinstrument für Interfaces in Videospielen legt. / The quality of a videogame’s interface is a decisive factor to its commercial success. However, the current evaluation methods focus primarily on qualitative research data like those generated in usability tests. Methods of inferential statistics are not common yet because of a lack of theoretical fundamentals. To address this issue, this paper provides a theoretical framework for quantitative analysis on different dimensions of interface design in videogames. Aspects of perception, psychology, sociology as well as culture are dealt with in this context and the associated scientific concepts are conflated by a theoretical extension of Huizinga’s “magic circle”. The technical term “genre” in regard to videogames is also discussed in this paper and it proves to be a basis for connecting the various concepts methodically. As a result, this paper presents a holistic model, which can be applied in future audience-specific and quantitative measuring instruments for interfaces in videogames.
64

Persuasive Kommunikation in Computerspielen

Valtin, Georg, Pietschmann, Daniel 27 October 2008 (has links)
Seit Menschen miteinander kommunizieren gibt es Persuasion, also das Bestreben, den Kommunikationspartner zu beeinflussen. Bereits in der Antike wurde dieses Handwerk in Form der klassischen Rhetorik systematisiert und gezielt eingesetzt. In den vergangenen Jahren gab es Versuche, diese etablierten Konzepte auf interaktive Medien zu übertragen, was aber nur ansatzweise gelang. Um den Besonderheiten interaktiver Medien gerecht zu werden, sollten ihre prozesshafte Natur und ihre Wechselwirkungen mit den Aktionen des Nutzers im Mittelpunkt stehen. Genau das ist beim Konzept der prozeduralen Rhetorik von Ian Bogost der Fall, weshalb dieser Ansatz als Grundlage der hier vorgenommenen Untersuchungen zu persuasiven Computerspielen dient. Im Rahmen der Arbeit werden zudem die unterschiedlichen Formen der Rhetorik vorgestellt und die Notwendigkeit der Berücksichtigung prozeduraler Rhetorik dargelegt. Anhand der Beispiele The McDonald's Videogame und America's Army verdeutlichen die Autoren den Einsatz verschiedener persuasiver Techniken aus klassischer und prozeduraler Rhetorik.
65

Wie kommt der Tod ins Spiel? Von Leichen und Geistern in Casual Games

Schreiter, Miriam 04 October 2018 (has links)
Diese Arbeit beschäftigt sich mit Tod in digitalen Spielen und geht der Frage nach, über welche Routen und Netzwerke der Tod ins digitale Spiel kommt. Ziel war es herauszufinden, wie Tod in digitalen Spielen repräsentiert wird, welche Praktiken im Zusammenhang mit Tod in digitalen Spielen erkennbar sind und welche soziokulturellen Aspekte und Konzepte von Tod in digitalen Spielen ausgehandelt und konstruiert werden. Im Mittelpunkt steht das Spielgenre der Casual Games, wobei der Untersuchungsfokus insbesondere auf den sog. Wimmelbildspielen oder Hidden Objekt Games liegt. In diesen Spielen dreht sich alles um das Sammeln, Kombinieren und Suchen von Gegenständen in dichten, mit Objekten überfüllten Wimmelbildszenen sowie um das Lösen von Rätseln und Puzzles. Zur Bearbeitung des Themas wurden im Rahmen einer ethnografischen Untersuchung verschiedene Methoden miteinander kombiniert (visuelle, textuelle und inhaltliche Analysen, Close Playing, ethnografische Gespräche und Dichte Beschreibung). Auf Basis vielfältigen Materials (digitale Wimmelbildspiele, Webseiten, Foren- und Bewertungsbeiträge, Let’s Plays, Berichte und Interviews, literarische Texte, Filme, Transkripte von Spielsessions) werden vier Beziehungsnetze herausgearbeitet, über die der Tod ins Spiel kommt. Das erste Beziehungsnetz beschreibt transmediale Zusammenhänge und durchzieht verschiedene Medien, wobei der Tod über alte, weitgereiste Stoffe, Motive und kulturelle Topoi ins Spiel kommt, die den Zwecken und Möglichkeiten des digitalen Mediums angepasst werden. Die drei anderen Beziehungsnetze werden unter dem Begriff der Ökonomie zusammengefasst: Anhand der Ökonomie der Aufmerksamkeit wird gezeigt, wie der Tod über kulturell und visuell etablierte Aufmerksamkeitsregimes, Todessymboliken und -motive ins Spiel kommt. Dass Tod auch Teil der Spielpraktiken selbst ist, weil er die Spielhandlungen initiiert und strukturiert, wird anhand der Ökonomie des Accomplishments dargelegt. Die Ausführungen zur Ökonomie des Wertes machen deutlich, wie Spielebewertungen sowie soziale Todes- und Sterbeerfahrungen die Beziehung zwischen Spieler, Spiel und Spieleproduzent mitbestimmen können. In der Arbeit wird somit nicht nur dargelegt, dass dem Thema Tod eine zentrale Rolle beim Spielen von digitalen Spielen zukommt, sondern auch, dass Tod die Gestaltung und Vermarktung dieser Spiele maßgeblich beeinflusst und somit ebenfalls Bestandteil alltäglicher digitaler Kommunikationsformen ist.
66

Detection of 18-methyl steroids: case report on a forensic urine sample and corresponding dietary supplements

Thieme, Detlef, Anielski, Patricia, Rzeppa, Sebastian, Wolf, Clemens A., Wolber, Gerhard, Keiler, Annekathrin M. 01 March 2024 (has links)
The detection of a putative 18-methyl-19-nortestosterone metabolite in a forensic bodybuilder's urine sample collected as part of a criminal proceeding has triggered a follow-up investigation. Four different dietary supplements in the possession of the suspect were examined with regard to possible precursor steroids. This led to the detection of the declared ingredient methoxydienone, which was confirmed by both, GC–MSMS and LC-HRMSMS. As neither 18-methyl-testosterone, nor 18-methyl-19-nortestosterone were detectable in the supplements, the possibility that the metabolite originates from methoxydienone was investigated. For this purpose, the metabolic fate of methoxydienone was studied in vitro using human HepG2 cells and in vivo by a single oral administration. While the 18-methyl-19-nortestosterone metabolite was not generated by HepG2 cells incubated with methoxydienone, it was observed in the urine samples collected at 2, 6, 10 and 24 h after methoxydienone administration. Moreover, the potential binding of methoxydienone as ligand to the human androgen receptor was modelled in silico in comparison with 18-methylnandrolone, for which androgen receptor activation had been shown in an in vitro approach before. In conclusion, we could ascribe the presence of the 18-methyl-19-nortestosterone metabolite in a forensic urine sample to originate from methoxydienone present in dietary supplements. Methoxydienone was observed to slowly degrade by demethylation of the methoxy substituent in liquid solutions. While no compound-specific intermediates were identified that allowed differentiation from other 18-methyl steroids, the 18-methyl-19-nortestosterone metabolite proved to be a suitable marker for reliable detection in doping analysis.
67

Agreement of steroid profiles in Athlete Biological Passport residues and corresponding serum samples

König, Simon, Rzeppa, Sebastian, Thieme, Detlef, Keiler, Annekathrin M. 26 February 2024 (has links)
The steroid module of the Athlete Biological Passport (ABP) is based on the analysis of six endogenous steroids in urine samples and a Bayesian statistical approach. However, the urinary steroid concentrations may be affected by confounders like microbial degradation, possible co-administration of diuretics as masking agents, insufficient conjugate hydrolysis or UGT2B17 gene polymorphisms affecting glucuronidation. Therefore, it can be helpful to use other matrices (ABP blood and serum samples) to quantify steroids and thereby support noticeable deviations in the Athlete Biological Passport, for example, abnormally increased urinary testosterone/epitestosterone (T/E) ratios. Aim of the study was to investigate the feasibility to re-use plasma obtained from athlete ABP blood samples for measuring a steroid profile. Therefore, testosterone, androstenedione, cortisol and cortisone were quantified in 36 intra-individual matching ABP blood and serum samples. The steroid levels measured in both matrices showed a high agreement indicating a good stability uninfluenced by storage temperature and duration. Our results pointed out the possibility to expand the athlete ABP blood analysis for steroid profiling.
68

Search For A Standart Model Higgs Boson In Cms Via Vector Boson Fusion In The H-ww-lvlv Channel And Optimization Of Energy Reconstruction In Cms Using Test Beam 2006 Data

Yazgan, Efe 01 July 2007 (has links) (PDF)
One of the goals of the LHC is to test the existence of the Higgs Boson. This thesis presents a study of the potential to discover the Standard Model Higgs boson in the vector boson fusion (VBF) channel for the Higgs mass range 120-200 GeV/c2. The decay of Higgs bosons into WW* final state with both W-bosons decaying leptonically is considered. The main backgrounds are tt_+j and W+W-jj. This study, based on a full simulation of the CMS detector at the LHC, shows that a 5(Sigma) discovery can be done with an integrated luminosity of 12-72 fb-1 for 130-200 GeV/c2 Higgs bosons. Due to the uncertainties in the backgrounds, it is important to measure the backgrounds from data. This study shows that the major background can be measured directly to 7% with 30 fb-1. After discovering the Higgs boson mass using transverse mass template distributions is investigated in the VBF channel. The performance of the combined CMS electromagnetic and hadronic calorimeters (EB+HB) was measured at the H2 test beam at the CERN SPS during 2006 with various partivles in a large momentum range, 1-350 GeV/c. Another major contribution of this thesis is developing the method to optimize the energy reconstruction for the combined EB+HB system with which the corrected responses become 100% with 6% fluctuation and the stochastic resolution is improved from 111% to 94%.
69

Graviton Induced Monojet Production In Cms Within Add Type Led

Surat, Ugur Emrah 01 July 2010 (has links) (PDF)
The discovery reach for the ADD-type Large Extra Dimension (LED) scenario in the CMS Experiment at the LHC is presented by looking at the Monojet + Missing Energy signature, which arises as a result of a single graviton emission accompanied by a quark or gluon. Using Monte Carlo generated events, two LHC run scenarios were considered and compared namely a center-of-mass energy of 14 TeV and integrated luminosity of 100 pb&amp / #8722 / 1, and a center-of-mass energy of 10 TeV and integrated luminosity of 200 pb&amp / #8722 / 1. Details from extensive trigger studies are presented and offline selection techniques that optimize the signal excess over backgrounds are highlighted. As a result of this study, it is shown that the existing Tevatron limits on the ADD model can be improved through the implementation of this analysis in CMS Experiment with a factor of 3 using the the early LHC data.
70

Measurement Of Differential Photon-jet Cross Section From 7 Tev Pp Collisions In The Cms Experiment At The Lhc

Ocalan, Kadir 01 March 2012 (has links) (PDF)
Prompt photons are produced primarily by quark-gluon compton scattering and quark-anti-quark annihilation mechanisms that their measurements are driven by several motivations at hadron colliders. Measurement of prompt photons can be used for probing perturbative Quantum Chromodynamics (pQCD). Prompt photons are produced in the final states of important decays providing evidence for low mass Higgs boson and new physics searches. Compact Muon Solenoid (CMS) is one of the multi-purpose experiments conducted at the Large Hadron Collider (LHC) to study the Standard Model (SM) physics including prompt photons and new theories in proton-proton collisions. In this thesis, photon reconstruction is discussed along with the photon identification methods in the CMS experiment. Photon efficiency measurements are presented as an important ingredient for photon+jet cross section measurement. Photon High Level Trigger (HLT) efficiencies, reconstruction (RECO) efficiencies, and identification (ID) efficiencies are presented that are measured from collision data recorded by the CMS detector and Monte Carlo simulation data. Efficiency corrected differential photon+jet cross section measurement results are presented in this study. The collision data used in this thesis corresponds to 2.2 /fb integrated luminosity collected by the CMS detector at a center-of-mass energy of 7 TeV from 2011 LHC proton-proton collision running.

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