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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.
1

The measurement of sporting performance using mobile physiological monitoring technology

Johnstone, James Alexander January 2014 (has links)
Coaches are constantly seeking more ecologically valid and reliable data to improve professional sporting performance. Using unobtrusive, valid and reliable mobile physiological monitoring devices may assist in achieving this aim. For example, there is limited information regarding professional fast bowlers in cricket and understanding this role during competitive in-match scenarios rather than in simulated bowling events could enhance coaching and physical conditioning practices. The BioharnessTM is a mobile monitoring device and assesses 5 variables (Heart rate [HR], Breathing frequency [BF], Accelerometry [ACC], Skin temperature [ST] and Posture [P]) simultaneously. Therefore, the aims of this research were to assess the effectiveness of the BioharnessTM mobile monitoring device during professional sporting performance using fast bowlers in cricket and this was to be achieved in five research studies. Study 1 presented the physiological profile of professional cricketers reporting fitness data with other comparable professional athletes, with a specific interest in fast bowlers who were to be the focus of this work. The 2nd and 3rd study assessed the reliability and validity of the BioharnessTM through controlled laboratory based assessment. For validity, strong relationships (r = .89 to .99, P < .01) were reported for HR, BF, ACC and P. Limits of Agreement reported HR (-3 ± 32 beat.min-1), BF (-3.5 ± 43.7 br.min-1) and P (0.2 ± 2.6o). ST established moderate relationships (-0.61 ± 1.98 oC; r =.76, P <.01). Reliability between subject data reported low Coefficient of Variation (CV) and strong correlations for ACC and P (CV < 7.6%; r = .99, P <.01). HR and BF (CV ~ 19.4%; r ~.70, P <.01) and ST (CV 3.7%; r = .61, P < .01), present more variable data. Intra and inter device data presented strong relationships (r > .89, P < .01, CV < 10.1%) for HR, ACC, P and ST. BF produced weaker data (r < .72, CV < 17.4%). Study 4 assessed reliability and validity of the BioharnessTM in a field based environment using an intermittent protocol. Precision of measurement reported good relationships (r = .61 to .67, P < .01) and large Limits of Agreement for HR (> 79.2 beat.min-1) and BF (> 54.7 br.min-1). ACC presented excellent precision (r = .94, P < .01). Results for HR (r = ~ .91, P < .01: CV <7.6%) and ACC (r > .97, P < .01; CV < 14.7%) suggested these variables are reliable in the field environment. BF presented more variable data (r = .46 - .61, P < .01; CV < 23.7%). In all studies, as velocity of movement increased (> 10 km.h-1) variables became more erroneous. HR and ACC were deemed as valid and reliable to be assessed during in-match sporting performance in study 5. This final study sought to utilise and assess the BioharnessTM device within professional cricket, assessing physiological responses of fast-medium bowlers within a competitive sporting environment, collected over three summer seasons. The BioharnessTM presented different physiological profiles for One Day (OD) and Multi Day (MD) cricket with higher mean HR (142 vs 137 beats.min-1, P < .05) and ACC (Peak acceleration (PkA) 227.6 vs 214.9 ct.episode-1, P < .01) values in the shorter match format. Differences in data for the varying match states of bowling (HR, 142 vs 137 beats.min-1, PkA 234.1 vs 226.6 ct.episode-1), between over (HR, 129 vs 120beats.min-1, PkA 136.4 vs 126.5 ct.episode-1) and fielding (115 vs 106 beats.min-1, PkA 1349.9 vs 356.1 ct.episode-1) were reported across OD and MD cricket. Therefore, this information suggests to the coach that the training regimes for fast bowlers should be specific for the different demands specific to the format of the game employed. Relationships between in-match BioharnessTM data and bowling performance were not clearly established due to the complexities of uncontrollable variables within competitive cricket. In conclusion, the BioharnessTM has demonstrated acceptable validity and reliability in the laboratory and the field setting for all variables (Heart rate, Breathing frequency, Accelerometry, Skin temperature and Posture) but with limitations for heart rate and breathing frequency at the more extreme levels of performance. Furthermore, taking these limitations into account it has successfully been utilised to assess performance and provide further insight into the physiological demands in the professional sport setting. Therefore, this work suggests that coaches and exercise scientists working together should seek to utilise new mobile monitoring technology to access unique insights in to sporting performance which may be unobtainable in the laboratory or a simulated field based event.
2

Analog Non-Linear Multi-Variable Function Evaluation By Piece-wise Linear Approximation

Desai, Dileep Reddy 25 August 2010 (has links)
No description available.
3

A Design and Optimization Methodology for Multi-Variable Systems

Lott, Eric M. January 2015 (has links)
No description available.
4

Weakest Bus Identification Based on Modal Analysis and Singular Value Decomposition Techniques

Jalboub, Mohamed K., Rajamani, Haile S., Abd-Alhameed, Raed, Ihbal, Abdel-Baset M.I. 12 February 2010 (has links)
Yes / Voltage instability problems in power system is an important issue that should be taken into consideration during the planning and operation stages of modern power system networks. The system operators always need to know when and where the voltage stability problem can occur in order to apply suitable action to avoid unexpected results. In this paper, a study has been conducted to identify the weakest bus in the power system based on multi-variable control, modal analysis, and Singular Value Decomposition (SVD) techniques for both static and dynamic voltage stability analysis. A typical IEEE 3-machine, 9-bus test power system is used to validate these techniques, for which the test results are presented and discussed.
5

Measuring Expected Returns in a Fluid Economic Environment

Evans, Donald C. III 15 March 2004 (has links)
This paper examines the components of the Capital Asset Pricing Model and the model's uses to analyze portfolios returns. It also looks at subsequent versions of the CAPM including a multi-variable CAPM with the inclusion of selected macro-variables as well as a non-stationary beta CAPM to estimate portfolio returns. A new model is proposed that combines the multi-variable component together with the non-stationary beta component to derive a new CAPM that is more effective at capturing current market conditions than the traditional CAPM with the fixed beta coefficient. The multi-variable CAPM with non-stationary beta is applied, together with the select macro-variables, to estimate the returns of a portfolio of assets in the oil-sector of the economy. It looks at returns during the period of 1995-2001 when the economy exhibited a wide range of variation in market returns. This paper tests the hypothesis that adapting the traditional CAPM to include beta non-stationarity will better estimate portfolio returns in a fluid market environment. The empirical results suggest that the new model is statistically significant at measuring portfolio returns. This model is estimated with an Ordinary Least Square (OLS) estimations process and identifies three factors that are statistically significant. These include quarterly changes in the Gross Domestic Product (GDP), the Unemployment Rate and the Consumer Price Index (CPI). / Master of Arts
6

Structures et stratégies de commande des filtres actifs parallèle et hybride avec validations expérimentales / Structures and control strategies of parallel active and hybrid filters with experimental validations

Abdusalam, Mohamed Muftah 29 May 2008 (has links)
Ce manuscrit est consacré à la dépollution des réseaux électriques par les filtres actifs. Dans un premier temps, le filtre actif parallèle triphasé trois fils à structure tension y est étudié théoriquement, par simulation, puis expérimentalement. Une nouvelle stratégie de commande, basée sur la méthode des puissances instantanées et mettant en œuvre des « filtres multi-variables » est étudiée. Trois types de contrôleurs de courant sont envisagés : hystérésis classique, hystérésis modulée et MLI. L’hystérésis modulée est retenue car elle garantit simultanément la robustesse du système et une fréquence de commutation fixe. Un banc expérimental a permis de conforter les résultats obtenus par simulation. Ensuite, le filtre hybride parallèle (FHP) triphasé et l’optimisation de sa commande ont été examinés. L’objectif majeur est d’améliorer les performances de filtrage tout en s’attachant à minimiser la complexité de la commande. Le filtre hybride étudié est constitué d’un filtre actif triphasé à structure tension connecté en série avec un filtre triphasé passif de type LC, accordé sur l’harmonique 7. Nous avons proposé une première modification (commande dite « simplifiée ») de la commande classique dans le référentiel lié au synchronisme en introduisant des « filtres multi-variables » au lieu des filtres d’extraction classiques des deux boucles de contrôle, dites « feedback » et « feedforward ». Cette modification nous a permis de réduire considérablement la complexité de l’algorithme de commande (suppression de la PLL de la boucle « feedforward ») tout en améliorant les performances du filtrage. Ensuite, la PLL de la boucle « feedback » a également été supprimée. Ces optimisations ont conduit à des résultats de simulation très satisfaisants en terme de THD. Une nouvelle commande du filtre hybride à trois bras a également été proposée. La boucle feedforward est alors divisée en deux boucles. La première est destinée à supprimer l’harmonique 5 et l’autre l’harmonique 7 alors que le filtre passif est alors accordé sur l’harmonique 11. Les résultats de simulation obtenus sont très satisfaisants. Pour conclure cette étude théorique, nous avons étudié une nouvelle topologie de filtre hybride basée sur un onduleur triphasé à deux bras avec un condensateur à point milieu. Un flot de conception et d’implantation sur cible FPGA de commandes numériques de systèmes de puissance a été appliqué au cas de la commande dite « simplifiée » du FHP. Chaque étape a été détaillée et validée soit par simulation en mode continu ou en mode discret, soit expérimentalement lors de la programmation finale d’un composant FPGA de type Stratix II de la famille Altera, intégrant l’ensemble de la commande numérique du FHP. / In this thesis, and with the aim to improve the power quality, we have theoretically and experimentally studied two types of filtering, the shunt active power filter and hybrid, passive and active power filter. The modelling and simulation of a parallel active filter with three types of current controllers (MLI, classical hysteresis and modulated hysteresis) are first studied. The behavior of the active filter under transient conditions is also presented. Then, we have experimentally validated the simulation results obtained for the modulated hysteresis. The test bench consists of a parallel active filter, a non-linear load, a digital control system DSPACE (DS1104) and an analog card. Next, we studied by modelling and simulation the hybrid filter. For both cases, the use of multi-variable filter improves the filtering performances. An experimental prototype called "FPGA in the Loop" has been implemented to validate digital control of hybrid filter. In addition, a comparison between the two filters has been realised in order to find the best way to reduce network harmonic currents.
7

AVALIAÇÃO DOS CRITÉRIOS DO PLANO DE PARTICIPAÇÃO NOS LUCROS POR MEIO DE INDICADORES DE DESEMPENHO / EVALUATION CRITERION ON PROFIT AND/OR RESULT-SHARING BY NEAN OF PERFORMANCE INDICATORS

Barasuol, Edelmar Eloi 22 February 2006 (has links)
The present study focuses on the research and evaluation of a profit- and/or result-sharing plan (PRSP) applied during 7 years at the CERTHIL Company. Multi-variable and descriptive analyses were the methods used. The objective of the research was to propose a methodology that would facilitate the implantation and evaluation of future profit-sharing plans at other companies. It is classified as a quantitative study. A questionnaire (Likert scale) was given to directors and collaborators of CERTHIL and directors of the company CERMISSÕES, which intends to implant the PRSP. The evaluation of indicators by the multi-variable analysis allowed for the selection of an ideal group of variables for analysis. The factorial analysis enabled the identification of the degree of importance of each indicator analyzed, facilitating the study of those indicators that have greater and lesser influence in the plan. The analysis of the principal components allowed for the reduction and identification of variables of greater statistical relevance, that better explain the factors to be analyzed and identify those that will maintain greater management control. The methodology proposed proved to be important and highly applicable in the evaluation and implantation of Profit- and/or Result-Sharing plans. This method can be used as a tool to monitor performance indicators applied to the PRSP and contribute to business planning. / O presente estudo concentra-se em uma pesquisa e avaliação do plano de participação nos lucros e resultado PLR aplicado há 7 anos na CERTHIL. Utilizou-se os métodos de análise descritiva e multivariada. O objetivo da pesquisa é avaliar os critérios do PLR por meio dos indicadores de desempenho aplicado aos processos produtivos. Classifica-se como pesquisa quantitativa. Aplicou-se um questionário valendo-se de uma escala Likert onde foi aplicado junto aos gestores e colaboradores da CERTHIL e gestores da CERMISSÕES - que pretende implantar a PLR. A análise descritiva foi útil para fazer o comparativo do entendimento e opinião dos respondentes de ambas as cooperativas sobre a PLR, quanto a sua implantação, influência na qualidade, lucratividade, gestão administrativa, motivação, relacionamento e comprometimento. A avaliação dos indicadores, através da análise multivariada, possibilitou selecionar um grupo ideal de variáveis para análise. A análise fatorial proporcionou a identificação do grau de importância de cada indicador analisado, facilitando o acompanhamento dos indicadores que influenciam em maior e menor importância na composição do plano. A análise de componentes principais possibilita reduzir e identificar as variáveis de maior relevância estatística, que mais expliquem os fatores a serem analisados e identifiquem as que deve manter um maior controle gerencial. Os procedimentos multivariados confirmam sua importância e aplicabilidade na avaliação e implantação de planos de participação nos lucros e resultados nas empresas. Pode-se utilizar,esse método, como ferramenta para monitorar indicadores de desempenho aplicados a PLR e contribuir na gestão administrativa.
8

Search for supersymmetric particles in final states with multi-leptons with the ATLAS detector / Recherche de particules supersymétriques dans des états finaux multileptoniques avec le détecteur ATLAS

Ren, Huan 18 October 2017 (has links)
Le grand collisionneur de Hadron (LHC), plus grand accelerateur au monde situe au CERN (Organisation Europeenne pour la recherche Nucleaire), produit des collisions proton proton collectees depuis 2009 par le detecteur ATLAS a une energie atteignant 8TeV dans le centre de masse en 2012 (Run1) et 13 TeV en 2015 et 2016 (Run2). Les modeles theoriques SuperSymetrique (SUSY), extension du Modele Standard (SM), relient chaque boson (de spin entier) a un fermion specifique (de spin demi entier) comme super partenaire. De nouvelles particules elementaires sont ainsi introduites. Apres une breve presentation du SM et des principaux modeles SUSY, the LHC et le detecteur ATLAS sont decrits suivi par une etude de performance sur l'isolation des taus. La partie principale du memoire decrit ensuite en detail deux recherches de particules SUSY avec le detecteur ATLAS et les resultats obtenus.La premiere recherche decrite est celle de production directe de stau avec un etat final a deux tau de signes opposes et plusieurs jets dans des collisions pp a 8TeV et une luminosite integree de 20.1 fb-1. Des techniques d’analyse multi variables ont ete utilisees pour ameliorer la sensibilite. Aucun exces significatif par rapport au SM n’a ete observe. Dans une recherche directe de stau, un signal avec m(LSP) = 0 GeV et m(stau) = 100 GeV est exclus.La deuxieme recherche presentee est celle de la production forte de squarks et de gluions avec des etats finaux, a deux leptons de memes signes ou a trois leptons, associees a des jets dans des collisions proton-proton a $\sqrt{s} = 13 TeV$ et une luminosite integree de 13.2 fb-1. Aucun exces significatif par rapport au SM n’a ete observe. / The Large Hadron Collider (LHC), largest collider located at CERN (European Organization for Nuclear Research). produces proton-proton collisions collected by the ATLAS detector since 2009 at a collision center of mass energy up to 8 TeV before 2012 (Run1) and 13 TeV in 2015 and 2016 (Run2). Supersymmetry (SUSY) theory models, extension of the Standard Model (SM), link each boson (of integer spin) to a certain fermion (of half integer spin) as super-partner. New elementary particles are then introduced.After a brief presentation of the Standard Model and of the main SUSY models, the LHC and the ATLAS detector are described followed by a performance study on tau isolation. The main part of the document finally describes in details two searches for SUSY particles with the ATLAS detector and the obtained results.The first one is a search for direct stau production with final state of two opposite sign taus and multi-jets in 8 TeV pp collision and 20.1 fb-1 integrated luminosity. Multivariable analysis techniques are used to improve the sensitivity. No significant excess over the SM expectation was observed. Upper-limit was set on the cross-section of the signal models. For “direct stau” search, we excluded the signalpoint with m(LSP) = 0 GeV and m(stau) = 100 GeV.The second one is a search for squarks and gluinos strong production in final states with jets and two same-sign leptons or three leptons at 13 TeV and 13.2 fb-1 integrated luminosity. No significant excess over the SM expectation was observed. Upper-limit was set on the cross-section of all the models involved. Region with gluino mass up to 1.7 TeV have been excluded.
9

Anomaly Detection using LSTM N. Networks and Naive Bayes Classifiers in Multi-Variate Time-Series Data from a Bolt Tightening Tool / Anomali detektion med LSTM neuralt nätverk och Naive Bayes klassificerare av multivariabel tidsseriedata från en mutterdragare

Selander, Karl-Filip January 2021 (has links)
In this thesis, an anomaly detection framework has been developed to aid in maintenance of tightening tools. The framework is built using LSTM networks and gaussian naive bayes  classifiers. The suitability of LSTM networks for multi-variate sensor data and time-series prediction as a basis for anomaly detection has been explored. Current literature and research is mostly concerned with uni-variate data, where LSTM based approaches have had variable but often good results. However, most real world settings with sensor networks, such as the environment and tool from which this thesis data is gathered, are multi-variable. Thus, there is a need to research the effectiveness of the LSTM model in this setting. The thesis has emphasized the need of well defined evaluation metrics of anomaly detection approaches, the difficulties of defining anomalies and anomaly datasets, as well as illustrated the effectiveness of LSTM networks in multi-variate environments. / I den här uppsatsen har ett anomali detektions ramverk utvecklats för att bidra till underhållandet av åtdragarverktyg. Ramverket bygger på LSTM neurala nätverk och gaussian Naive Bayes klassificerare. Användbarheten av LSTM nätverk för multi-variabel data och tidsserie prediktion som basis för anomali detektion har undersökts. Nutida literatur och forskning berör mest envariabel data där LSTM baserade metoder ofta har presterat bra. Men, de flesta system i verkligheten är inte envariabel utan multivariabel, som den miljö verktyget, vars data undersöks i den här uppsatsen, opererar i. Därför anses det att det finns ett behov att undersöka användbarheten av LSTM modeller i den här typen av miljö. Det här arbetet har betonat vikten av väldefinierade utvärderingsvärden för anomali detektion, svårigheterna med att definiera anomalier och anomalidataset, samt illustrerat användbarheten av LSTM nätverk i multivariabla miljöer.
10

Meteorologically adjusted trends of ozone and dispersion of air pollutants in the Hsuehshan Tunnel

Li, Han-chieh 22 June 2010 (has links)
This study separated two parts: PART ¢¹ Meteorologically adjusted trends of ozone Since meteorological changes strongly affect ambient ozone concentrations, trends in concentrations of ozone upon the adjustment of meteorological variations are important of evaluating emission reduction efforts. This work is to study meteorological effects on the long-term trends of ozone concentration using a multi-variable additive model in Kaohsiung. The long-term trends of ozone concentration were analyzed using the Holland model (without meteorological-adjusted) and the robust MM Regression model (with meteorological-adjusted) based on the data of eight EPA air quality stations from 1997 to 2006 in Kaohsiung area. According to the result of the simulation, the simulated value of the robust MM-Regression model present more valid than the Holland model.The simulated results show that the long-term ozone concentration increases at 13.84% (or 13.06%) monthly (or annually) after meteorological adjustments, less than at 26.10% (or 23.80%) without meteorological adjustments in Kaohsiung county. The simulated results show that the long-term ozone concentration increases at 9.01% (or 6.88%) monthly (or annually) after meteorological adjustments, less than at 22.01% (or 19.67%) without meteorological adjustments in Kaohsiung city. Wind speed, duration of sunshine and pressure are the three dominant factors that influence the ground-level ozone levels in Kaohsiung area. PART ¢º Dispersion of air pollutants in the Hsuehshan Tunnel Concentrations of carbon monoxide (CO) and nitrogen oxides (NOx) were measured from November 14 ¡V 17 2008 in a cross-mountain Hsuehshan traffic tunnel stretching 12.9 km and containing eastward and westward channels. Air pollutants of CO (carbon monoxide) and NOx (nitrogen oxides) will be monitored at the inlet, outlet and vertical shafts of the tunnel. Meanwhile, numerical simulation of three-dimensional turbulent flow will be performed using STAR-CD software. Traffic and pollutant concentrations during the weekends exceeded those during the weekdays. Measured concentrations of CO at the two tunnel outlets (14.5 ¡V 22.8 ppm) were approximately three times higher than those at the two tunnel inlets (3.2 ¡V 7.3 ppm), while concentrations of NOx at the two tunnel outlets (1.9 ¡V 2.9 ppm) were approximately four to five times higher than those at the two tunnel inlets (0.3 ¡V 0.8 ppm). The outlet of vertical draft 2 had the highest pollutant concentrations (CO = 12.3 ppm; NOx = 1.9 ppm), followed by vertical drafts 1 and 3. Three-dimensional turbulence modeling results indicate that airflow in the tunnel was primarily driven by the combined effects of axial fans and vehicles. Results of this study demonstrate that simulated pollutant concentrations increase downstream and are vertically stratified, due to tailpipe exhausts close to tunnel floor. Simulations agreed fairly well with measurements.

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