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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.
171

Measurements of Angular Correlations in Minimum Bias Events and Preparatory Studies for Charged Higgs Boson Searches at the Tevatron and the LHC

Bélanger-Champagne, Camille January 2011 (has links)
Studies of minimum bias events at colliders probe the behavior of QCD in the non-perturbative regime. The phenomenology of events in this regime is described by empirical models that take many parameters, which all need to be tuned to the observed data. Measurements based on angular correlations between the highest transverse momentum charged particle track and the other charged particle tracks in collision events can, because of their robustness against experimental and detector effects, be a component of the tuning inputs for the models. We measure such observables in a variety of pseudorapidity ranges and at many center-of-mass energies at DØ and ATLAS. We observe that such observables are poorly described by current models and tunes that are used to produce simulated event samples, making them valuable information for the tuning process. The Matrix Element method is a powerful analysis tool to extract precise measurements from data samples of limited statistics. We have investigated the potential of the Matrix Element method to measure the mass of the charged Higgs in the exclusive decay H±→τ±ν→e±+3ν when produced in top quark decays at the Tevatron, with emphasis on the construction of transfer functions in the τ decay chain. We concluded that the τ decay chain can be successfully parametrized via a transfer function and that the method has the potential to provide an accurate charged Higgs mass measurement in this channel. Triggering on τ leptons is a key component for many beyond the Standard Model searches at ATLAS, such as the search for the charged Higgs boson. Events containing Z bosons can be used to measure the efficiency of the ATLAS τ hadronic-decay trigger. We have used a tag-and-probe method on simulated Z boson decays to 2 τ leptons where one decays to a μ while the other decays hadronically. The μ is used as the tag and the τ side is probed. We demonstrated that the efficiency of the τ hadronic-decay trigger can be accurately measured with this method using the first 100 pb-1 of ATLAS data. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 732
172

Einfluss eines Beatmungshelmes auf die Leistung zweier verschiedener Intensivbeatmungsgeräte im Vergleich zu einer Gesichtsmaske und zur invasiven Beatmung - Eine experimentelle Lungenmodelluntersuchung / Influence of a helmet for noninvasive ventilation on the mechanical properties and performance of a respiratory system compared to a facemask and invasive ventilation - a lung model study

Fischer, Sven 10 October 2012 (has links)
No description available.
173

Moterų griaučių raumenų sistemos viršutinės dalies funkcinės būklės įvertinimas prieš ir po pasyvios ir aktyvios kineziterapijos priemonių taikymo / Evaluation of women’s upper part of musculoskeletal system functional state before and after active and passive physical therapy

Erlickytė, Jolanta 21 June 2010 (has links)
Tyrimo tikslas: Įvertinti moterų griaučių raumenų sistemos viršutinės dalies funkcinę būklę prieš ir po pasyvios ir aktyvios kineziterapijos priemonių taikymo. Tyrimo uždaviniai: 1. Įvertinti moterų griaučių raumenų sistemos viršutinės dalies raumenų skausmo slenksčio pokyčius prieš ir po pasyvios ir aktyvios kineziterapijos. 2. Nustatyti moterų griaučių raumenų sistemos viršutinės dalies judesių amplitudės pokyčius prieš ir po pasyvios ir aktyvios kineziterapijos priemonių taikymo. 3. Įvertinti moterų griaučių raumenų sistemos viršutinės dalies raumenų jėgos pokyčius prieš ir po pasyvios ir aktyvios kineziterapijos. 4. Palyginti pasyvios ir aktyvios kineziterapijos priemonių efektyvumą moterų griaučių raumenų sistemos viršutinės dalies raumenų skausmo slenksčiui, judesių amplitudei bei raumenų jėgai. Tyrimo metodai: Buvo ištirtos 20 jauno ir vidutinio amžiaus sveikos moterys. Tiriamosios buvo suskirstytos į dvi grupes. Vienai grupei buvo taikomos pasyvios kineziterapijos priemonės, kitai – aktyvios. Prieš ir po kineziterapijos buvo vertinamas spaudimo sukeltas raumenų skausmo slenkstis (algometru), žasto judesių amplitudė (goniometru), rankų sukabinimo už nugaros ir kaklo judesių amplitudė (centimetrine juostele), pečių juostos raumenų jėga (rankos dinamometru ir „Stabilizer Pressure Biofeedback“ prietaisu). Išvados: 1. Po pasyvios kineziterapijos priemonių taikymo raumenų skausmo slenkstis statistiškai reikšmingai padidėjo 20- yje iš 22- jų vertintų miofascijinių... [toliau žr. visą tekstą] / The aim of the research: To evaluate women’s upper part of musculoskeletal system functional state before and after passive and active physical therapy. To achieve this aim the following tasks were set up: 1. To evaluate changes of muscle pain threshold in the upper part of the musculoskeletal system. 2. To assess changes of range of motion in the upper part of the musculoskeletal system. 3. To evaluate changes of muscle force in the upper part of the musculoskeletal system. 4. To compare the effect of passive and active physical therapy for the muscle pain threshold, range of motion and muscle force in the upper part of the musculoskeletal system. Method of the research: 20 young and middle-aged healthy women were tested. Subjects were divided in to two groups. We have applied passive physical therapy modalities for the first group, active physical exercises for the second group. We have assessed the muscle pain threshold (using algometer), the range of motion (goniometer and tape – measure) and muscle force (hand held dynamometer and „Stabilizer Pressure Bioffedback“) before and after passive and active physical therapy. Conclusions: 1. After the passive physical therapy the muscle pain threshold statistically significant increase in the 20 of 22 assessed myofascial trigger points (p<0,05). After active physical therapy - the muscle pain threshold a statistically significant increase in 12 of 22 assessed myofascial trigger points (p<0,05). 2. After passive physical... [to full text]
174

Miofascijinių trigerinių taškų terapijos ir tempimo pratimų poveikis skausmui ir kaklo judesių amplitudei / The impact of myofascial trigger poin therapy and streching exercises on pain and cervical range of motion

Vaišnoraitė, Lina 10 September 2013 (has links)
Tyrimo problema: miofascijinis skausmo sindromas, sukeltas aktyvių miofascijinių trigerinių, taškų vargina lėtiniais raumenų skausmais, sutrikdo judesių amplitudę, miegą ir gyvenimo kokybę. Latentiniai miofascijiniai trigeriniai taškai bet kuriuo metu, paveikti bet kokio mechaninio stimulo gali tapti aktyviais. Gydant ir taip šalinant latentinius miofascijinius trigerinius taškus užkertamas kelias aktyvių miofascijinių trigerinių taškų formavimuisi ir tuo pačiu miofascijinio skausmo sindromo atsiradimui. Tyrimo objektas: kaklo judesių amplitudės ir miofascijinių trigerinių taškų sukelto skausmo pokyčiai taikant miofascijinių trigerinių taškų terapiją ir tempimo pratimus. Tyrimo tikslas: nustatyti miofascijinių trigerinių taškų terapijos ir tempimo pratimų poveikį skausmui ir kaklo judesių amplitudei. Tyrimo uždaviniai: 1. Nustatyti išeminės kompresijos poveikį galvos sukamojo ir trapecinio viršutinės dalies raumenų miofascijinių trigerinių taškų sukeltam skausmui ir kaklo judesių amplitudei. 2. Nustatyti išeminės kompresijos ir tempimo pratimų poveikį galvos sukamojo ir trapecinio viršutinės dalies raumenų miofascijinių trigerinių taškų sukeltam skausmui ir kaklo judesių amplitudei. 3. Palyginti išeminės kompresijos taikomos atskirai ir kartu su tempimo pratimais veiksmingumą mažinant galvos sukamojo ir trapecinio viršutinės dalies raumenų miofascijinių trigerinių taškų sukeltą skausmą ir didinant kaklo judesių amplitudę. 4. Nustatyti miofascijinių trigerinių taškų sukelto... [toliau žr. visą tekstą] / Problem of study: Myofascial pain syndrome, caused by active myofascial trigger points, causes chronic muscle pain, restricts range of motion, decreases sleep and quality of life. Latent myofascial trigger points at any time can transforme into active myofascial trigger points, when a mechanical stimulus appears. Treating and eliminating latent myofascial trigger points prevent latent myofascial trigger points from transforming into active myofascial trigger points, and hence, prevent the development of myofascial pain syndrome. Object of study: changes of cervical range of motion and myofascial trigger points pain after application of myofascial trigger point therapy and streching exercises. Aim of study: to determine the impact of myofascial trigger point therapy and streching exercises for MTrPs pain and cervical range of motion. Goals of study: 1. To determine the change of sternocleidomastoid and upper trapezius muscles myofascial trigger points pain and cervical range of motion, when ischemic compression is applied. 2. To determine the change of sternocleidomastoid and upper trapezius muscles myofascial trigger points pain and cervical range of motion, when ischemic compression and streching exercises are applied. 3. To compare the effectiveness of ischemic compression and streching exercises on sternocleidomastoid and upper trapezius muscles myofascial trigger points pain and cervical range of motion. 4. To determine the relation beatween myofascial trigger points pain... [to full text]
175

Evaluation of gigabit links for use in HEP trigger processing

Anderson, Christopher R. January 1999 (has links)
No description available.
176

Probing the Quark-Gluon Plasma from bottomonium production at forward rapidity with ALICE at the LHC

Marchisone, Massimiliano 06 December 2013 (has links) (PDF)
The main goal of ultrarelativistic heavy-ion collisions is the study of the properties of the matter at very high temperatures and energy densities. Quantum chromodynamics (QCD) predicts in these conditions the existence of a new phase of the matter whose components are deconfined in a Quark-Gluon Plasma (QGP). Heavy quarks (charm e bottom) are produced in the first stages of the collisions, before to interact with the medium. Therefore, the measurement of the quarkonia (cc and bb mesons) is of particular interest for the study of the QGP: their dissociation mainly due to the colour screening is sensible to the initial temperature of the medium. Previous measurements at the SPS and RHIC allowed to understand some characteristics of the system produced, but they also opened many questions. With an energy 14 times higher than RHIC, the LHC (Large Hadron Collider) at CERN opened a new era for the study of the QGP properties. ALICE (A Large Ion Collider Experiment) is the LHC experiment fully dedicated to the study of the Quark-Gluon Plasma produced in Pb-Pb collisions at an energy of 2.76 TeV per nucleon. The experiment also participates to the proton-proton data taking in order to obtain the fundamental reference for the study of ion-ion and proton-ion collisions and for testing the predictions at very small Bjorken-x values of the perturbative QCD. Quarkonia, D and B mesons and light vector mesons are measured at forward rapidity by a Muon Spectrometer exploiting their (di)muonic decay. This detector is composed of a front absorber, a dipole magnet, five stations of tracking (Muon Tracking) and two stations of trigger (Muon Trigger). The work presented in this thesis has been carried out from 2011 to 2013 during the first period of data taking of ALICE. After a detailed introduction of the heavy-ion physics and a description of the experimental setup, the performance of the Muon Trigger in Pb-Pb collisions are shown. A particular attention is devoted to the stability of the detector during the time and to the trigger effectiveness. Moreover, the cluster size, corresponding to the number of adjacent strips hit by a particle, is studied as a function of different variables. The experimental results will be compared to simulations in order to obtain a good parametrization of this phenomenon. Finally, the Ç production in Pb-Pb collisions is carefully analysed and compared to that in pp collisions at the same energy. The results are then compared to the J/ψ measurements obtained by ALICE, to the CMS results and to some theoretical predictions.
177

Sequential prediction for budgeted learning : Application to trigger design

Benbouzid, Djalel 20 February 2014 (has links) (PDF)
Classification in machine learning has been extensively studied during the pastdecades. Many solutions have been proposed to output accurate classifiers and toobtain statistical grantees on the unseen observations. However, when machinelearning algorithms meet concrete industrial or scientific applications, new computationalcriteria appear to be as important to satisfy as those of classificationaccuracy. In particular, when the output classifier must comply with a computationalbudget needed to obtain the features that are evaluated at test time, wetalk about "budgeted" learning. The features can have different acquisition costsand, often, the most discriminative features are the costlier. Medical diagnosis andweb-page ranking, for instance, are typical applications of budgeted learning. Inthe former, the goal is to limit the number of medical tests evaluate for patients,and in the latter, the ranker has limited time to order documents before the usergoes away.This thesis introduces a new way of tackling classification in general and budgetedlearning problems in particular, through a novel framework lying in theintersection of supervised learning and decision theory. We cast the classificationproblem as a sequential decision making procedure and show that this frameworkyields fast and accurate classifiers. Unlike classical classification algorithms thatoutput a "one-shot" answer, we show that considering the classification as a seriesof small steps wherein the information is gathered sequentially also providesa flexible framework that allows to accommodate different types of budget constraintsin a "natural" way. In particular, we apply our method to a novel type ofbudgeted learning problems motivated by particle physics experiments. The particularityof this problem lies in atypical budget constraints and complex cost calculationschemata where the calculation of the different features depends on manyfactors. We also review similar sequential approaches that have recently known aparticular interest and provide a global perspective on this new paradigm.
178

The effect of soluble organic carbon substrates, and environmental modulators on soil microbial function and diversity

Hoyle, Frances Carmen January 2007 (has links)
[Truncated abstract] The principal aim of this thesis was to examine the response of the microbial community to the addition of small amounts (<50 μg C g-1 soil) of organic C substrates (‘trigger molecules’) to soil. This addition is comparative to indigenous soluble C concentrations for a range of soil types in Western Australia (typically measured between 20 and 55 μg C g-1 soil). Previously it has been reported that the application of trigger molecules to European soils has caused more CO2-C to be evolved (up to six fold) than was applied . . . Findings from this study indicated that there was an additional CO2 release (i.e. greater than the C added) on application of organic C substrates to some soil treatments. However, findings from this study indicate that the response of the microbial community to small additions of soluble C substrate is not consistent for all soil types and may vary due to greater availability of C, and supports the premise that microbial responses vary in a yet to be predicted manner between soil type and ecosystems. Differences in microbial response to the addition of soluble organic C are likely attributable to differences in soil attributes and environmental factors influencing both the diversity of microbes present and the frequency of food events. Theoretically, trigger molecules could also provide a possible control mechanism for microorganisms in arable farming systems. These mechanisms include stimulating either targeted pathogenic microorganisms that starve after depletion of a suitable substrate; or stimulating beneficial microorganisms to manipulate nutrient cycling, by targeting specific functional groups and altering mineralisation and immobilisation turnover rates.
179

Search for the standard Higgs boson produced in association with a pair of top quark in the multi-leptons channel in the CMS experiment / Recherche du boson de Higgs standard produit en association avec une paire de quarks top dans le canal multi-leptons dans l'expérience CMS

Coubez, Xavier 15 September 2017 (has links)
La découverte en 2012 de la dernière particule élémentaire prédite par le Modèle Standard, le boson de Higgs, a ouvert une nouvelle ère en physique des particules. L’un des objectifs est désormais de sonder les couplages du boson de Higgs aux autres particules afin de confirmer la validité du modèle. Le travail de cette thèse a porté dans un premier temps sur l’identification de jets issus de quark b dès le système de déclenchement. L’objectif est de permettre de sélectionner un millier d’événements parmi les quarante millions produits chaque seconde au LHC en identifiant des objets présents dans l’état final de processus de physique intéressants tels que la production associée d’un boson de Higgs se désintégrant en paire de quark b avec un boson Z se désintégrant en neutrinos non détectés. Dans un second temps, l’étude du couplage du boson de Higgs au quark top, particule la plus massive au sein du Modèle Standard a été réalisée. Après l’étude d’un bruit de fond important de la production associée d’un boson de Higgs et d’une paire de quarks top, une nouvelle méthode a été utilisée pour améliorer la discrimination entre le signal et les principaux bruits de fond. Cette analyse a conduit à la première évidence expérimentale du couplage entre le boson de Higgs et le quark top. / The discovery in 2012 of the last elementary particle predicted by the Standard Model, the Higgs boson, has opened a new era in particle physics. One of the objectives now is to probe the coupling of the Higgs boson to other particles in order to confirm the validity of the model. The work of this thesis focused initially on the identification of jets coming from b quark at trigger level. The goal is to allow for the selection of one thousand events among the forty million produced every second at the LHC, by identifiying objects present in the final states of interesting physics processes such as the associated production of a Higgs boson decaying in a pair of b quark with a Z boson decaying into undetected neutrinos. The work then moved to the study of the coupling of the Higgs boson to the quark top, most massive particle in the Standard Model. After a study of one of the important background of the associated production of the Higgs boson and a top quark pair, a new method called matrix element method has been used to improve the discrimination between signal and background. This analysis has led to the first experimental evidence of coupling between the Higgs boson and the top quark.
180

Measurement of the differential cross section of Z boson production in association with jets at the LHC

Wang, Qun 13 June 2018 (has links)
This thesis presents the measurement of the differential cross section of Z boson pro-duction in association with jets (Z+jets) in proton-proton collision at the center-of-massenergy of 13 TeV. The data has been recorded with the CMS detector at the LHC duringthe year 2015, corresponding to an integrated luminosity of 2.19 fb −1 .A study of theCMS muon High Level Trigger (HLT) with the data collected in 2016 is also presented.The goal of analysis is to perform a first measurement at 13 TeV of the cross sections ofZ+jets as a function of the jet multiplicity, its dependence on the transverse momentumof the Z boson, the jet kinematic variables (transverse momentum and rapidity), thescalar sum of the jet momenta, and the balance in the transverse momentum betweenthe reconstructed jet recoil and the Z boson. The results are obtained by correctingthe detector effects, and are unfolded to particle level. The measurement are com-pared to four predictions using different approximations: at the leading-order (LO),next-to-leading-order (NLO) and next-to-next-to-leading order (NNLO) accuracy. Thefirst two calculations used M AD G RAPH 5_ A MC@NLO interfaced with PYTHIA 8 for theparton showering and hadronisation, one of which includes matrix elements (MEs) atLO, another includes one-loop corrections (NLO). The third is a fixed-order calculationwith NNLO accuracy for Z+1 jet using the N -jettiness subtraction scheme (N jetti ). Thefourth uses the GENEVA program with an NNLO calculation combined with higher-order resummation.A series of studies on the HLT double muon trigger are also included. Since 2015 theLHC reached higher luminosity, more events are produced inside the CMS detector persecond, which resulted in more challenges for the trigger system. The work presentedincludes the monitoring, validation and the calibration of the muon trigger paths since2016. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

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