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Al-Abbass, Faysal. "Decentralized model reference adaptive systems with variable structure controllers /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487266691094338.
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Shubo, Jin, and Zhao Yanshan. "A MICROWAVE DIGITAL FREQUENCY SYNTHESIZER USED FOR S-BAND TELEMETRY RECEIVER." International Foundation for Telemetering, 1997. http://hdl.handle.net/10150/609681.
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International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, NevadaThis paper describes a kind of Microwave Digital Frequency Synthesizer used for S-band telemetry receivers. As well known many modern electronic systems employ a Frequency Synthesizer whose spectral purity is critical. The characteristics of a PLL (Phase-Locked Loop) Frequency Synthesizer, such as frequency resolution, phase noise, spurious suppression and switch time, should be compromised in our design. A heterodyne Frequency Synthesis is often considered as a good approach to solve the problem. But it is complicated in structure and circuit. A variable-reference-driven PLL Frequency Synthesizer was introduced which can give an improved trade-off among frequency resolution, phase noise, spurious suppression. In this paper the phase noise and spurious suppression characteristic of variable-reference-driven PLL Frequency Synthesizer is analyzed theoretically and compared with that of the heterodyne Frequency Synthesizer. For engineering application, a practical Microwave Digital Frequency Synthesizer used for telemetry receiver has been designed, which is characterized by simply structure, low phase noise and low spurious output. The output spectrum of experimental measurements is given.
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Casper, Adlerteg, and Sen Adem. "Navigation with variable point of reference for 3DOF differential drive mobile robot." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-54574.
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In this thesis, a kinematic model for controlling an Omni-directional 3 DOF DDR with an external navigation point is presented. Two different dynamic models for investigating the resulting torque on the three active motors on the robot are also developed and validated. The focus of the thesis is on the design of kinematic and dynamic models in an ideal environment and the kinematic model in a high fidelity environment. The kinematic model uses inverse kinematics to translate the controlling motion reference from the external navigation point to the three active motors on the DDR. The thesis also includes a comparison of the two different dynamic models based on Kane's method and Newton's second law of motion, respectively. The models presented in this thesis could aid autonomous robots with attached payloads such as hospital beds move with the centre of geometry as a focal point and thereby perform movements. The results show that such a kinematic model for controlling the specific robot is shown to be feasible in an ideal environment. However, due to PID controllers for the active wheel motors not being exact enough, the model in the high fidelity environment does not perform correctly in all cases. Furthermore, the dynamic model results provide an understanding of the difference of torque dependant on the distance to the navigation point.
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Jacome, Isael Calistrato. "Controle adaptativo por modelo de referencia e estrutura vari?vel discreto no tempo." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18573.
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With the technology progess, embedded systems using adaptive techniques are being used frequently. One of these techniques is the Variable Structure Model- Reference Adaptive Control (VS-MRAC). The implementation of this technique in embedded systems, requires consideration of a sampling period which if not taken into consideration, can adversely affect system performance and even takes the system to instability. This work proposes a stability analysis of a discrete-time VS-MRAC accomplished for SISO linear time-invariant plants with relative degree one. The aim is to analyse the in uence of the sampling period in the system performance and the relation of this period with the chattering and system instability
Com o avanco da tecnologia, sistemas embarcados utilizando t?cnicas adaptativas est?o sendo utilizados com mais frequencia. Uma dessas t?cnicas ? o Controlador adaptativo por Modelo de Referencia e Estrutura Variavel (VS-MRAC). A implementa??o dessa t?cnica em sistemas embarcados, requer a considera??o de um per?odo de amostragem que se n?o for levado em considera??o, pode afetar de maneira negativa a performance do sistema e at? mesmo lev?-lo a instabilizacao. Este trabalho prop?e uma an?lise de estabilidade do VS-MRAC para o caso discreto para uma planta SISO linear, invariante no tempo, de grau relativo unit?rio. O objetivo ? analisar a influ?ncia do per?odo de amostragem no desempenho do sistema, e a rela??o desse per?odo com o fen?meno de "chattering" e instabiliza??o do sistema
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Phillips, Robert Allan. "Clinical applications of high frame rate digital ultrasound and variable reference M-mode echocardiography /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19510.pdf.
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Jackson, Caroline Margaret. "Towards a theory of variable personality : a study with reference to the Palestinian situation." Thesis, University of Bristol, 2001. http://hdl.handle.net/1983/a2cdf83f-7706-463a-969e-612dd5824eb7.
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This thesis is primarily concerned with the question of personality in international law. In order to assessp ersonality the vehicles of the Palestinian situation and representation of Palestinians in the West Bank and Gaza Strip are used. Therefore at points in the study each dominates in order to further the overall thesis. The study looks beyond the jaded constitutive/declaratory debate regarding recognition and personality and examines recent state practice, which sheds further light on the issue. A flexible approach to personality is taken and it is asserted that the best description of the process of recognition and achievement of status for both emerging states and representative groups is that an entity's status can be variable: variable in an evolutionary sense, in relation to the range of responses which the international community may have and also in relation to status on the international stage. Thus an entity may operate with different degrees of status at any one point in time depending on with whom and what circumstances are in question. This theory is then examined in relation to the Palestinian situation. The progression of the Palestinian Liberation Organisation and the Palestinian Authority on the world stage is investigated through, inter alia, their relationships with other states and international organisations. The variability theory asserted above appears to be borne out in the Palestinian context which leads on to questions of what broader implications this may have for other areas of international law. Two subject areas are then discussed in relation to the implications of the theory of variable personality. First, the concept of responsibility which has traditionally been adopted in relation to states rather than other entities on the international stage. Second, the protection of the rights of those placed under the jurisdiction of an entity with variable levels of personality, noting that this is also an issue which is generally dealt with at a state level. In each examination the Palestinian situation is drawn upon to provide concrete examples of the possible problems which may arise for other areas of international law due to the theory of variable personality. Examples of ways in which those issues could be reconciled are also considered. Lastly, both subject areas provide further important conclusions in relation to the assertion that personality may be variable.
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Misbach, Charlotte. "Determination of reference intervals in small size dogs for variables used in veterinary cardiology." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30304/document.
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La dégénérescence valvulaire mitrale (MVD) est la cardiopathie la plus fréquente chez le chien de petit format. Certaines variables écho-Doppler et sanguines sont incontournables dans son évaluation mais nécessitent d'être interprétées selon un intervalle de référence (IR) spécifique. L'objectif de ce travail a été de déterminer des IR pour 31 variables d'utilité clinique en cardiologie vétérinaire dans une population importante de chiens sains de petit format et selon les recommandations du Clinical and Laboratory Standard Institute. Les trois études réalisées permettent de conclure que l'élaboration d'IR spécifiques dans une sous-population canine est pertinente pour certaines variables. De plus, l'effet de certains facteurs comme le poids, l'âge et le sexe doivent être pris en compte si un intérêt clinique est identifiéDegenerative mitral valve disease is the most common heart disease in small size dogs. Several echocardiographic, Doppler and blood variables are crucial in the assessment of the disease but need to be interpreted in the light of a specific reference interval (RI). The aim of this work was to determine RI for 31 variables of clinical interest in veterinary cardiology within a large population of healthy small size dogs by using the Clinical and Laboratory Standard Institute recommendations. The three studies performed here allowed to conclude that determination of specific RI in this canine sub-population is relevant. Moreover, the effect of covariates such as body-weight, age and gender should be taken into account only if a clinical interest is identified
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Wiles, Jonathan. "The Effects of isometric excercise on selected cardiovascular Variables with specific reference to blood pressure." Thesis, University of Kent, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499702.
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Ullah, Saif. "Effect of Dividend Policy Measures on Stock Prices : With Reference to Karachi Stock Exchange, Pakistan." Thesis, Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-7825.
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The objective of this study is to examine the dividend policy measures effect on the stock prices. A sample of 171 listed companies from Karachi Stock Exchange, Pakistan is examined for a period from 1998 to 2006. The dependent variable stock price volatility is regressed against the dividend policy measures (independent variables) e.g., dividend yield, dividend payout ratio, actual cash dividends and dividend to total assets of the firm, after controlling for firms’ profitability, liquidity, gearing, size and growth. This study finds that, dividend policy measures have strong effect on the stock market prices but results are contradictory to earlier research in Pakistan. Dividend payout and actual cash dividends have negative, significant relationship with stock prices and dividend yield have significant positive relationship with stock market prices.
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Bouscasse, Hélène. "Essays on travel mode choice modeling : a discrete choice approach of the interactions between economic and behavioral theories." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE2106/document.
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Cette thèse a pour objectif d’incorporer des éléments de théories de psychologie et d’économie comportementale dans des modèles de choix discret afin d’améliorer la compréhension du choix modal réalisé à l’échelle régionale. Les estimations se basent sur une enquête de type choice experiment présentée en première partie. Une deuxième partie s’intéresse à l’incorporation de variables latentes pour expliquer le choix modal. Après une revue de littérature sur les modèles de choix hybrides, c’est-à-dire des modèles combinant modèle d’équations structurelles et modèle de choix discret, un tel modèle est estimé pour montrer comment l’hétérogénéité d’outputs économiques (ici, la valeur du temps) peut être expliquée à l’aide de variables latentes (ici, le confort perçu dans les transports en commun) et de variables observables (ici, la garantie d’une place assise). La simulation de scénarios montre cependant que le gain économique (diminution de la valeur du temps) est plus élevé lorsque les politiques agissent sur des dimensions palpables que sur des dimensions latentes. S’appuyant sur un modèle de médiation, l’estimation d’un modèle d’équations structurelles montre par ailleurs que l’effet de la conscience environnementale sur les habitudes de choix modal est partiellement médié par l’utilité indirecte retirée de l’usage des transports en commun. Une troisième partie s’intéresse à deux formalisations de l’utilité issues de l’économie comportementale : 1) l’utilité dépendante au rang en situation de risque et 2) l’utilité dépendante à la référence. Dans un premier temps, un modèle d’utilité dépendante au rang est inséré dans des modèles de choix discret et, en particulier, un modèle à classes latentes, afin d’analyser l’hétérogénéité intra- et inter-individuelle lorsque le temps de déplacement n’est pas fiable. La probabilité de survenue d’un retard est sur-évaluée pour les déplacements en train et sous-évaluée pour les déplacements en voiture, en particulier pour les automobilistes, les usagers du train prenant d’avantage en compte l’espérance du temps de déplacement. Dans les modèles prenant en compte l’aversion au risque, les fonctions d’utilité sont convexes, ce qui implique une décroissance,de la valeur du temps. Dans un deuxième temps, une nouvelle famille de modèles de choix discret généralisant le modèle logit multinomial, les modèles de référence, est estimée. Sur mes données, ces modèles permettent une meilleure sélection des variables explicatives que le logit multinomial et l’estimation d’outputs économiques plus robustes, notamment en cas de forte hétérogénéité inobservée. La traduction économique des modèles de référence montre que les meilleurs modèles empiriques sont également les plus compatibles avec le modèle de dépendance à la référence de Tversky et KahnemanThe objective of this thesis is to incorporate aspects of psychology and behavioral economics theories in discrete choice models to promote a better understanding of mode choice at regional level. Part II examines the inclusion of latent variables to explain mode choice. A literature review of integrated choice and latent variable models – that is, models combining a structural equation model and a discrete choice model – is followed by the estimation of an integrated choice and latent variable model to show how the heterogeneity of economic outputs (here, value of time) can be explained with latent variables (here, perceived comfort in public transport) and observable variables (here, the guarantee of a seat). The simulation of scenarios shows, however, that the economic gain (decrease in value of time) is higher when policies address tangible factors than when they address latent factors. On the basis of a mediation model, the estimation of a structural equation model furthermore implies that the influence of environmental concern on mode choice habits is partially mediated by the indirect utility derived frompublic transport use. Part III examines two utility formulations taken from behavioral economics: 1) rankdependent utility to model risky choices, and 2) reference-dependent utility. Firstly, a rank-dependent utility model is included in discrete choice models and, in particular, a latent-class model, in order to analyze intra- and inter-individual heterogeneity when the travel time is subject to variability. The results show that the probability of a delay is over-estimated for train travel and under-estimated for car travel, especially for car users, as train users are more likely to take into account the expected travel time. In the models that account for risk aversion, the utility functions are convex, which implies a decrease in value of time. Secondly, a new family of discrete choice models generalizing the multinomial logit model, the reference models, is estimated. On my data, these models allow for a better selection of explanatory variables than the multinomial logit model and a more robust estimation of economic outputs, particularly in cases of high unobserved heterogeneity. The economic formulation of reference models shows thatthe best empirical models are also more compatible with Tversky et Kahneman’s reference-dependent model
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Weaver, David. "Norm-referenced construct validation of the Adaptive Behavior Scale for Infants and Early Childhood (ABSI) using covariance structure modeling (LISREL) /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487266362339311.
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Drut, Amandine. "La mesure de l’homocystéinémie plasmatique chez le chat : validité de la méthode de chromatographie liquide haute performance couplée à la spectrométrie de masse en tandem, déterminants biologiques, intervalle de référence et application aux maladies rénales chroniques." Thesis, Nantes, Ecole nationale vétérinaire, 2019. http://www.theses.fr/2019ONIR131F.
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L'homocystéinémie est un bio-marqueur utilisé en médecine humaine pour le diagnostic précoce des carences en cobalamine ou en folates et pour l’évaluation du risque cardiovasculaire dans certains contextes pathologiques comme l’insuffisance rénale chronique. En médecine vétérinaire, plusieurs études commencent à s’intéresser au statut de l’homocystéine chez l’animal malade. Le premier objectif de notre étude a été de définir les déterminants biologiques et l’intervalle de référence de l’homocystéinémie plamatique chez le chat adulte sain, après avoir vérifié la validité de la méthode de chromatographie liquide haute performance – spectrométrie de masse en tandem. Notre travail a confirmé l’adéquation de cette technique pour le dosage de l’homocystéine dans le plasma de chat. L’étude de l’homocytéinémie plasmatique chez le chat sain a fourni un intervalle de référence étendu, montrant une forte variabilité interindividuelle que nous ne sommes pas parvenus à expliquer par des déterminants épidémiologiques. Une influence de la teneur alimentaire en protéines et de la créatininémie a été mis en évidence. Une signature métabolique forte a été identifiée au sein d’un groupe d’animaux présentant une homocystéinémie élevée, suggérant une altération du métabolisme de l’homocystéine chez certains chats sains. Le second objectif de notre travail a été de comparer l’homocystéinémie plasmatique entre une population de chats atteints de maladie rénale chronique stable et la population de chats sains établie précédemment. Cette étude menée sur un petit nombre de chats atteints de maladie rénale chronique n’a pas mis en évidence de différence par rapport à la population de référenceIn human medicine, plasma plasma homocysteine concentration is a biomarker used for early diagnosis of cobalamin or folate deficiencies, and cardiovascular risk assessment in some medical conditions such as chronic kidney failure. ln veterinary medicine, several studies are beginning to address the status of homocysteine in diseased animals. The first objective of our study was to define the biological determinants and the reference interval of plasma homocysteine concentration in healthy adult cats, after having verified the concentration validity of the high-performance liquid chromatography - tandem mass spectrometry method. Our work confirmed the suitability of this technique for the measurement of homocysteine in feline plasma. The study of plasma homocysteine concentrations in healthy cats provided a particularly wide reference interval, showing high inter-individual variability that we were not able to explain by epidemiological determinants. We described an influence of the dietary protein content and plasma creatinine concentration. A strong metabolic signature was identified in a group of animals with elevated plasma homocysteine concentrations, suggesting alterations in the homocysteine metabolism in some healthy cats. The second aim of our work was to compare plasma homocysteine concentrations between a population of cats with stable chronic kidney disease and the previously established population of healthy individuals. This study of a small number of cats with chronic kidney disease did not show any differences from the reference population
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Al-Salim, Taha Hussein. "A comparative application of flood routing models on the rivers Wear and Tees with special reference to the state variable model." Thesis, Durham University, 1995. http://etheses.dur.ac.uk/5126/.
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An analysis of a number of flood routing methods has been carried out in this study. These methods are namely, the Muskingum-Cunge Method, the Variable Parameter Diffusion Method, the State Variable Kinematic Wave Model, and the state variable modelling of nonlinear Muskingum Model. The Muskingum-Cunge and Variable Parameter Diffusion Methods are recommended for use on British Rivers by the Natural Environment Research Council flood studies report, 1975.In using numerical flood routing model, it is very important to calculate the model parameters. For instance storage routing models require a suitable form of storage-discharge relationship. Past flow records were used for the above calculation. The state Variable Kinematic Wave Model has been applied for routing the flood hydrograph through river reaches. The stage and discharge are computed by a kinematic wave routing technique using the state variable approach in which the one-dimensional differential equations of unsteady flow are solved by state and output equations of the state variable model. The nonlinear Muskingum equation has been solved using the state variable modelling technique. Two parameter estimation techniques namely, Hooke-Jeeves and linear regression, are employed for the calibration of the nonlinear Muskingum model parameters (a, x, and m).The applicability of the flood routing model computer programs to different flood events of different seasons for reaches of both the Rivers Wear and Tees is demonstrated. Discriptions of the geology and hydrological data for reaches of both the Rivers Wear and Tees are given in this study. The computed and observed hydrographs of flood routing models used in this study are compared.
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Hamerlain, Mustapha. "Commande hiérarchisée à modèle de référence et à structure variable d'un robot manipulateur à muscles artificiels." Toulouse, INSA, 1993. http://www.theses.fr/1993ISAT0013.
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La legerete et la souplesse des robots manipulateurs (ceux utilisant des actionneurs a muscles artificiels en particulier) justifient le recours a des algorithmes de commande robustes. Les correcteurs a structure variable travaillant en mode de glissement sont une solution au probleme de la commande de systemes non lineaires. L'auteur presente le principe d'une commande discontinue, adaptative et hierarchisee. La methodologie est detaillee dans le cas d'un systeme non lineaire a n axes et n actionneurs dans un espace a 2n dimensions: sur une hypersurface de glissement, la dynamique du systeme boucle multivariable est plongee dans celle d'un systeme reduit et libre. Les resultats obtenus en regulation et en poursuite sur un degre de liberte puis sur trois degres de liberte motorises par des muscles artificiels pneumatiques sont compares a ceux fournis par un algorithme de commande classique de type pid. La validite de cette technique de commande est confirmee par les resultats d'experimentation qui montrent sa robustesse vis-a-vis des interactions entre les axes, de la variation de la charge manipulee, de la connaissance incertaine de l'ordre du systeme et des parametres dynamiques. L'analyse de cette methodologie est regroupee dans des tableaux de synthese qui offrent un outil de base utile pour la commande des systemes non lineaires
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Leung, Wai-cheung Ricky. "The effects of academic self-concept, gender and family variables on school achievement, with special reference to junior secondaryunderachievers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B29789849.
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Mitchell, Jayne. "The association of selected coronary heart disease risk factor variables between family members, with specific reference to physical activity." Thesis, University of Exeter, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292377.
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Manotas, Gonzalez Norha Cecilia. "Descentralizacion y participacion: dos variables democraticas tensiones y distennsiones en el sector salud, referencias a Brasil y Colombia." reponame:Repositório Institucional do FGV, 1997. http://hdl.handle.net/10438/3428.
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Previous issue date: 1997The mam purpose of this study is the decentralization analysis and the participation as democratical categories of the State's rearrangement specialy in the field of health policy in Brazil and Colombia. A theorical analysis was accomplished on the both categories and it's impact in the reformation of the relationship between State and society in order to examine it's conjunction on the reformulation, implementation and control of the health policys. The results founded allowed us to elaborated na analitical landmark of gradation leveI' s of decentralization and participation as well as the significances of these in the practice of a more democratical health management.
Este estudio tiene como tema central el análisis de la descentralización y la participación, como categorias democratizantes de la reforma de Estado, particulannente en la política de salud de Brasil y Colombia. Se realizó un análisis teórico de las dos categorias y de su impacto en la refonnulación de la relación Estado y sociedad, para en el último capítulo examinar su conjunción en la formulación, implementación y control de las políticas de salud. Los resultados obtenidos permitieron elaborar un marco analítico de graduación de niveles de descentralización y participación, así como, la importancia de éstas en la práctica de una gestión de la salud más democrática.
Este estudo tem, como tema central, a análise da descentralização e da participação como categorias democratizantes da reforma do Estado, particularmente, na área das políticas de saúde no Brasil e na Colômbia. Foi realizada uma análise teórica de ambas as categorias e de seu impacto na reformulação da relação Estado e sociedade para examinar, no último capítulo, sua conjunção na formulação, implementação e controle das políticas de saúde. Os resultados obtidos permitiram elaborar um marco analítico de gradação dos níveis de descentralização e participação assim como a importância destas na prática de uma gestão de saúde mais democrática.
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Kazemi, Ali School of Modern Language Studies UNSW. "A systematic study of self-repairs in second language classroom presentations: with some reference to social variables and language proficiency." Awarded by:University of New South Wales. School of Modern Language Studies, 2006. http://handle.unsw.edu.au/1959.4/24298.
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Self-repairs have been the subject of investigation in a number of research areas, notably psycholinguistics and conversation analysis. This study has aimed at the examination of self-repairs in second language classroom presentations. Specifically, it has sought to gain insight into self-repairs in naturally occurring talk and to explicate the possible relationships between the variables of age, sex, and educational background and self-repair behaviour of L2 speakers as well as the possible link between self-repair and proficiency. Accomplishing these required a scrutiny of individual self-repairs and their classification. However, the classifications which have traditionally been used in the psycholinguistic approach suffer from a number of shortcomings, as they are usually based on the analysis of surface forms of self-repairs. Because of the subjectivity involved in this process, there has been considerable variation in terms of classes of self-repairs and also the decision as to where a given self-repair belongs. An in-depth analysis of self-repair data revealed that self-repairs do cluster into categories. This analysis also yielded a set of features which are relevant to the study of self-repairs. In addition to showing that the established categories are mutually exclusive, comparison of major categories of self-repairs according to these features, which characterise the trajectory of self-repairs, resulted in the explication of a number of regularities in the way L2 speakers carry out self-repairs. Having established a data-driven classification of repairs, an attempt was made to see whether learner variables of age, sex and educational background have any significant effect on self-repairs. It turned out that none of these variables have a significant effect on self-repairs. In addition, it became clear that while beginning, intermediate, and advanced L2 speakers have been shown to demonstrate significant proficiency-related differences, these differences fade away when they come from the same proficiency level.
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Devereux, G. "The effects of isometric exercise training on resting blood pressure with specific reference to selected cardiovascular, neuromuscular, and metabolic variables." Thesis, Canterbury Christ Church University, 2010. http://create.canterbury.ac.uk/6974/.
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There were two purposes to the work of this thesis (a) to identify the role of isometric training intensity in the training-induced reductions in resting blood pressure, and (b) to identify whether the mechanism for the reduced resting blood pressure is best reflected in what can be broadly termed cardiovascular, neuromuscular or metabolic markers of that training. Firstly, in a cross-sectional study, the only strong correlation was found between heart rate variability (a cardiovascular marker) and resting blood pressure. Secondly, this cardiovascular marker was also significantly affected by a single session of isometric exercise, an effect that persisted for at least 4 hours after exercise. However, thirdly, this marker and other cardiovascular markers (such as cardiac output and stroke volume) did not correlate with reductions in blood pressure seen after 4 weeks of isometric training. Instead, the training-induced reductions in blood pressure correlated strongly with neuromuscular and metabolic markers of isometric training. The extent to which local muscle fatigue was induced during isometric training correlated with the reductions in resting blood pressure. Therefore (a) isometric training intensity appears to be of utmost importance in the reductions in resting blood pressure (when bilateral-leg exercise is performed in 2 minute bouts), and (b) the mechanism whereby the adaptations in resting blood pressure occur is best reflected in neuromuscular and metabolic markers of local muscle fatigue during that training. These findings are discussed with a particular focus on the possible role of muscle metaboreceptor stimulation, during isometric training in the mechanism of training-induced reduction in resting blood pressure.
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Ochoa, Banafsheh K. "Maxillary growth in comparison to mandibular growth." Oklahoma City : [s.n.], 2002. http://library.ouhsc.edu/epub/theses/Ochoa-Banafsheh-K.pdf.
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Abbas, Aghababazadeh Farnoosh. "Estimating the Local False Discovery Rate via a Bootstrap Solution to the Reference Class Problem: Application to Genetic Association Data." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33367.
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Modern scientific technology such as microarrays, imaging devices, genome-wide association studies or social science surveys provide statisticians with hundreds or even thousands of tests to consider simultaneously. Testing many thousands of null hypotheses may increase the number of Type $I$ errors. In large-scale hypothesis testing, researchers can use different statistical techniques such as family-wise error rates, false discovery rates, permutation methods, local false discovery rate, where all available data usually should be analyzed together. In applications, the thousands of tests are related by a scientifically meaningful structure. Ignoring that structure can be misleading as it may increase the number of false positives and false negatives. As an example, in genome-wide association studies each test corresponds to a specific genetic marker. In such a case, the scientific structure for each genetic marker can be its minor allele frequency.
In this research, the local false discovery rate as a relevant statistical approach is considered to analyze the thousands of tests together. We present a model for multiple hypothesis testing when the scientific structure of each test is incorporated as a co-variate. The purpose of this model is to incorporate the co-variate to improve the performance of testing procedures. The method we consider has different estimates depending on the tuning parameter. We would like to estimate the optimal value of that parameter by considering observed statistics. Thus, among those estimators, the one which minimizes the estimated errors due to bias and to variance is chosen by applying the bootstrap approach. Such an estimation method is called an adaptive reference class method. Under the combined reference class method, the effect of the co-variates is ignored and all null hypotheses should be analyzed together.
In this research, under some assumptions for the co-variates and the prior probabilities, the proposed adaptive reference class method shows smaller error than the combined reference class method in estimating the local false discovery rate, when the number of tests gets large. We describe the adaptive reference class method to the coronary artery disease data, and we use simulation data to evaluate the performance of the estimator associated with the adaptive reference class method.
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Gustafsson, Jonatan. "Linearization Based Model Predictive Control of a Diesel Engine with Exhaust Gas Recirculation and Variable-Geometry Turbocharger." Thesis, Linköpings universitet, Fordonssystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-174829.
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Engine control systems aim to ensure satisfactory output performance whilst adhering to requirements on emissions, drivability and fuel efficiency. Model predictive control (MPC) has shown promising results when applied to multivariable and nonlinear systems with operational constraints, such as diesel engines. This report studies the torque generation from a mean-value heavy duty diesel engine with exhaust gas recirculation and variable-geometry turbocharger using state feedback linearization based MPC (LMPC). This is accomplished by first introducing a fuel optimal reference generator that converts demands on torque and engine speed to references on states and control signals for the MPC controller to follow. Three different MPC controllers are considered: a single linearization point LMPC controller and two different successive LMPC (SLMPC) controllers, where the controllers are implemented using the optimization tool CasADi. The MPC controllers are evaluated with the World Harmonized Transient Cycle and the results show promising torque tracking using a SLMPC controller with linearization about reference values.
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Dann, Rebekkah S. Koch Gary G. "Methods for strengthening the design and analysis of clinical trials to show non-inferiority of a new treatment to a reference treatment for a binary response variable." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,705.
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Thesis (DrPH)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Doctorate of Public Health in the School of Public Health (Biostatistics)." Discipline: Biostatistics; Department/School: Public Health.
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Bonsall, James P. T. "A reappraisal of archaeological geophysical surveys on Irish road corridors 2001-2010. With particular reference to the influence of geological, seasonal and archaeological variables." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/7348.
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Geophysical surveys in the Republic of Ireland and elsewhere rarely have the opportunity to receive direct, meaningful and quantitative feedback from ground observed excavations, despite their frequent occurrence as a subsequent phase of development-led archaeological projects. This research critically reappraises the largest and most coherent geophysical archive maintained by a single end-user over a ten year period. The geophysical archive has been collated from 170 reports on linear road schemes as a result of commercially-driven assessments in Ireland, to facilitate the biggest analysis of geophysical survey legacy data and subsequent detailed excavations.
The analysis of the legacy data archive has reviewed and tested the influence of key variables that have, in some circumstances, affected the methods and outcomes of geophysical assessments in Ireland over the last 10 years. By understanding the impact of those key variables upon the legacy data - which include archaeological feature type, geology, sampling strategy and seasonality - appropriate and new ways to research linear corridors have been suggested that should be employed in future geophysical survey assessments for a range of environments and archaeological site types. The comprehensive analysis of geophysical surveys from the legacy data archive has created definitive statements regarding the validity of geophysical techniques in Ireland. Key failures that occurred in the past have been identified and a thorough investigation of new and novel techniques or methods of survey will facilitate a more robust approach to geophysical survey strategies in the future. The outcomes of this research are likely to have ramifications beyond the Irish road corridors from which the legacy data derives.National Roads Authority (NRA)
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Bonsall, James Peter Thomas. "A reappraisal of archaeological geophysical surveys on Irish road corridors 2001-2010 : with particular reference to the influence of geological, seasonal and archaeological variables." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/7348.
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Geophysical surveys in the Republic of Ireland and elsewhere rarely have the opportunity to receive direct, meaningful and quantitative feedback from ground observed excavations, despite their frequent occurrence as a subsequent phase of development-led archaeological projects. This research critically reappraises the largest and most coherent geophysical archive maintained by a single end-user over a ten year period. The geophysical archive has been collated from 170 reports on linear road schemes as a result of commercially-driven assessments in Ireland, to facilitate the biggest analysis of geophysical survey legacy data and subsequent detailed excavations. The analysis of the legacy data archive has reviewed and tested the influence of key variables that have, in some circumstances, affected the methods and outcomes of geophysical assessments in Ireland over the last 10 years. By understanding the impact of those key variables upon the legacy data - which include archaeological feature type, geology, sampling strategy and seasonality - appropriate and new ways to research linear corridors have been suggested that should be employed in future geophysical survey assessments for a range of environments and archaeological site types. The comprehensive analysis of geophysical surveys from the legacy data archive has created definitive statements regarding the validity of geophysical techniques in Ireland. Key failures that occurred in the past have been identified and a thorough investigation of new and novel techniques or methods of survey will facilitate a more robust approach to geophysical survey strategies in the future. The outcomes of this research are likely to have ramifications beyond the Irish road corridors from which the legacy data derives.
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Engström, Alexander, and Patrik Jogedal. "Kunskapsvarians vid förhandlingar : En studie om hur kunskapsvarians påverkar förankringseffekten vid förhandlingar." Thesis, Högskolan i Gävle, Avdelningen för ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-21572.
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Syfte: Denna uppsats behandlar en undermedveten kognitiv bias vilken benämns som ”anchoring effect” eller förankringseffekten. Effekten uppenbaras då människor tenderar att lägga för mycket tillit till den första informationen som görs tillgänglig vid olika typer av beslutsfattande. Teoriramen för detta forskningsområde är tämligen utbredd med drygt 40 år av studier som på senare tid börjat undersöka förankringseffektens påverkan vid förhandlingar. Dessutom finns utbredda konstateranden för att betydande kunskap inte lindrar effekten i någon större omfattning. Däremot föreligger bristande forskningsslutsatser kring hur kunskapsvarians vid förhandlingar påverkar förankringseffekten. Till följd av detta avser studien att undersöka nedanstående syfte: Syftet med denna studie är att undersöka hur förankringseffekten påverkar utfallet i en förhandlingssituation, när kunskapsvarians råder mellan parterna gällande det aktuella förhandlingsområdet. Metod: I studien genomfördes ett experiment med totalt 44 deltaganden. Experimenten utgjordes av prisförhandlingar gällande en fiktiv bostad, där varje enskild deltagare fick genomgå två förhandlingar vardera. Den första förhandlingen avsåg en lägenhetsförsäljning och den andra en villaförsäljning där parterna agerade säljare respektive köpare. I experimentgruppen förelåg det kunskapsvarians då tredjeårsstudenter från fastighetsmäklarprogrammet mötte studenter med annan utbildningsbakgrund. I kontrollgruppen ställdes motsatsvis deltagare från samma utbildning mot varandra för att skapa mindre skillnader i kunskap beträffande det aktuella förhandlingsområdet. Resultat & slutsats: Resultatet i denna studie tyder på att deltagare vars kunskap stod dem till förfogande, alstrat förmånligare överenskommelser i jämförelse med deltagare med låg kunskapsnivå. Detta trots att deltagarna vars kunskapsnivå var låg, erhållit fördelen av förankringseffekten då de fick lägga det första budet. Resultatet indikerar därmed att förankringseffekten kan lindras till följd av kunskapsvarians vid förhandlingar. Förslag till vidare forskning: Vidare forskning bör utgå från liknande förhandlingsexperiment där forskaren i första hand eftersträvar att generera större kunskapsskillnader mellan parterna i förhandlingen. En större omfattning av denna studie torde således resultera i ökade statistiska klarheter vilket torde vara gynnsamt för det aktuella forskningsområdet. Uppsatsens bidrag: Studiens bidrag är att forskningsresultaten tyder på en lindring av förankringseffekten vid kunskapsvarians inom förhandlingar. Detta till skillnad från tidigare studier där olika kunskapnivåer inte visats ha någon större betydelse. I och med att ingen tidigare studie undersökt detta förhållande har denna studie lyckats identifiera ett tydligt forskningsgap som bidragits till.Aim: This paper is about a subconscious cognitive bias referred to as "Anchoring Effect". The effect is revealed by the fact that people tend to put too much trust in the first information that is made available in different types of decision-making situations. The theory framework for this research area is fairly widespread with over 40 years of studies, and lately the research has begun examining the anchoring effect in different types of negotiation dyads. In addition, there are widespread findings that significant knowledge does not mitigate the effect in any notable degree. However, there is a lack of research findings regarding how differences in knowledge within negotiations might affect the anchoring effect. Therefore, this study intends to investigate the following: The purpose of this study is to investigate how the anchoring effect is affecting the outcome of a negotiation, when the parties have different levels of knowledge regarding the negotiated area. Method: This study has conducted an experiment with a total of 44 participants. The experiments have involved simulated price negotiations regarding a condominium and a residence property. Each participant performed two negotiations each, one for respective dwelling place. In the experimental group, there was a difference in knowledge when third year students from a real estate brokering program negotiated with students from other programs. In contradistinction to the experimental group, the control group included students with similar education background in order to create minor knowledge differences within the negotiated area. Result & Conclusion: The result of this study shows undeniably that the experiment participants with greater knowledge have generated more favourable agreements, compared to the participants with lower relevant knowledge. Even though the participants with lower knowledge had the advantage of presenting the initial offer in the experimental group. Thus, a mitigation of the anchoring effect has been identified as a result of differences in knowledge within the negotiations. Further research: Further research should be based on similar negotiation experiments with focus on creating greater differences in knowledge between the participants. This in combination with a larger replica of our study should enable increased statistical clarities with fruitful outcomes in this research field. Contribution of the thesis: The theoretical contribution of our study is primarily the fact that the anchoring effect tends to be mitigated by variance in knowledge within negotiations. Considering that no previous studies have examined this before, we argue that a clear research gap have been identified and that our findings has contributed to the theoretical framework.
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Baross, Anthony W. "The effects of isometric exercise and training on cardiovascular variables with specific reference to blood pressure and vascular parameters in middle-aged (45-60) Men." Thesis, Canterbury Christ Church University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.594268.
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The main focus of this thesis was to establish the effects of a novel method of undertaking isometric exercise training on resting arterial blood pressure in middle aged (45-60 years) males and to further determine whether isometric exercise training could generate concomitant adaptations in local or systemic vasculature function and structure. This novel method allowed exercise intensities to be set at a relative proportion of peak electromyographic activity (%EMGpeat). which provides a more accurate means of determining isometric exercise intensity than the traditional use of%MVC. Methods: Prior to the start of the experimental sIDdies preliminary tests were undertaken to determine the reliability of the equipment and measures used to determine the main dependant variables, including resting blood pressure using a non-invasive blood pressure monitor and vascular diameter, blood flow and velocity, using a Doppler ultrasound. During all three srudies participants completed either a unilateral or bilateral leg incremental isometric test during which heart rate, blood pressure and EMG were recorded. During the final study, resting heart rate, blood pressure and vascular measures were taken at pre, mid and post 8 weeks of isometric exercise training. Results: The linear relationship betvleen %EMG and heart rate reported in the initial study was not consistently evident in all subjects which further established the bilateral protocol as the preferred method for determining such relationships. The data from the second study involving bilateral leg isometric exercise indicated that these relationships in middle aged participants were linear in all cases, for both habitually active and sedentary individuals, showing that this method of prescribing isometric exercise intensity could be used in this age group. From the training data it is evident that following 8 weeks of bilateral isometric exercise training heart rate, SBP and mean arterial pressure (MAP) was significantly reduced in the higher (85%T) training group with concomitant local vascular adaptations. However, no significant change in resting blood press~e or vascular adaptations was evident in the lower (70%T) intensity group. These data has not been reported previously. Discussion: These results are in agreement with the majority of the previous research which have used isometric exercise training as an intervention for lowering arterial blood pressure. Furthermore, the findings lend support to the research evidence that" systeniic vascular adaptations are not responsible for the observed reductions in resting blood pressure foHowing isometric exercise training. Furthennore, the absence of changes in the 70%T group suggest the possibility of an exercise intensity threshold below which the exercise intensity is insufficient to stimulate cardiovascular adaptations.
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Hubbard, Scott. "A longitudinal study of the theory of parallel growth." Oklahoma City : [s.n.], 2008.
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Liyanage, Indika Jananda Borala, and n/a. "An Exploration of Language Learning Strategies and Learner Variables of Sri Lankan Learners of English as a Second Language with Special Reference to Their Personality Types." Griffith University. School of Cognition, Language and Special Education, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040716.112300.
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This study explores the relationship between language learning strategies and learner variables of Sri Lankan learners of English as a Second Language (ESL) with special reference to their personality types to examine what implications these associations have for the teaching of ESL in the Sri Lankan sociocultural context. In order to investigate the above, a large and representative sample of the ESL population was chosen. The sample taken for analysis comprised 886 subjects from six secondary schools which operate under the Ministry of Education in the Sri Lankan government. These subjects belonged to three distinct subcultures as demarcated by their first language (L1), Religion and Ethnicity in Sri Lanka. Data were collected using two questionnaires - a language learning strategy inventory and a personality assessment questionnaire, between April 2002 and June 2002 in Sri Lanka. Two statistical tests were used to measure the associations between the learner variables and language learning strategies: Multivariate Analysis of Variance (MANOVA) and Univariate Analysis of Variance (ANOVA). The findings show differences in strategy use or rather the ways the three groups learn the target language indicating that these strategy choices are closely correlated to their personality type, gender and religion/ethnicity. The findings also indicate that these variables affect the strategy choices both as collective and individual forces and when working as collective forces there is a complex interplay between these variables. While this study clearly demonstrates the association between learner variables and language learning strategies, it acknowledges the possible dangers in discussing these associations in cross-cultural comparisons. It also suggests the need for more ethnographic research to further elucidate the findings obtained in the current study. Based on these findings in the current study, this thesis strongly argues that ELT pedagogy cannot be independent of the Sri Lankan sociocultural context. It is therefore strongly suggested that ELT pedagogies should: (1) develop within the socio -cultural contexts of the learners; (2) be orientated to the culture of speakers of a Sri Lankan variety of English; (3) incorporate teaching material based on rhetoric indigenous to their culture. The study also shows the complexities of ESL instruction in the Sri Lankan socio-cultural context where its history, different cultures, first languages, ethnicities and religions all make a significant contribution to the learning/teaching of the target language. The challenge for teaching ESL in Sri Lanka is even higher given that all languages come with their own cultural, historical and ethnic trappings.
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Martí, Pérez Pau Carles. "Aplicación de redes neuronales artificiales para predicción de variables en ingeniería del riego: evapotranspiración de referencia y pérdidas de carga localizadas en emisores integrados." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/64909.
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En esta tesis se presenta la aplicación de redes neuronales artificiales (ANNs) para modelar dos variables de gran importancia en la ingeniería del riego: la evapotranspiración de referencia y las pérdidas de carga localizadas provocadas por los emisores integrados. Por una parte, se ha propuesto un modelo ANN para la predicción de las pérdidas de presión ocasionadas por la inserción de emisores integrados en los laterales de riego localizado, lo que nunca se ha llevado a cabo mediante redes neuronales. Por otro lado, se ha analizado la validez de un modelo ANN de 4 inputs existente para predicción de ETo en distintos contextos continentales de la Comunidad Valenciana y se ha planteado un nuevo modelo ANN de 6 inputs para mejorar el rendimiento del anterior.
Para llevar a cabo dichos estudios, se ha recurrido al uso de perceptrones multinivel (MLP) sometidos al algoritmo Levenberg Marquardt. En los tres casos, se analizaron redes con múltiples configuraciones y se repitió el proceso de entrenamiento de cada red un número variable de veces para compensar el efecto derivado de la asignación inicial aleatoria de pesos en dicho proceso. Asimismo, en los tres problemas abordados se llevaron a cabo distintas estrategias en la asignación de los datos disponibles a los conjuntos de entrenamiento, validación cruzada y test.
A diferencia de los modelos estadísticos existentes, el modelo ANN propuesto para predicción de pérdidas de carga localizadas posee indicadores de rendimiento referidos a un set de test independiente, lo que ha permitido evaluar su potencial real de generalización. Para diferentes combinaciones de validación cruzada, con datos al menos de tres emisores, se obtuvieron valores medios del performance index por encima de 0.85. En cuanto a los modelos de predicción de ETo, el rendimiento del modelo existente de 4 inputs depende del grado de oscilación térmica del contexto continental en que se utilice y su validez fuera de la sede de entrenamiento es muy limMartí Pérez, PC. (2009). Aplicación de redes neuronales artificiales para predicción de variables en ingeniería del riego: evapotranspiración de referencia y pérdidas de carga localizadas en emisores integrados [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/64909
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Williams, Joanne Ruth. "The blood lactate response to exercise in children aged 11 to 16 years with reference to cardiorespiratory variables, chronological age, sex, sexual maturity & habitual physical activity." Thesis, University of Exeter, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278304.
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Ross, John. "The autecology of the meadow thistle (Cirsium dissectum L. Hill) on Devon RHoS pastures, with particular reference to the effect of major environmental variables on the population dynamics." Thesis, University of Plymouth, 1999. http://hdl.handle.net/10026.1/2474.
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Semi-natural wet grassland communities are rapidly disappearing from the farmed landscape. Protection of remaining areas and restoration of degraded areas has become a priority with organisations concerned with the conservation of biodiversity in the U.K. The research described in this thesis provides an insight into the community dynamics of one particularly rare plant community, the Cirsio-Molinietum fen meadow (NVC M24). This was achieved by examining the autecology of Cirsium dissectum, one of the key indicator species of this community. The habitat environment where C. dissectum is present was characterised at eight Devon M24 locations and ten non-M24 locations. This revealed a particularly unique suite of environmental conditions. Soil water content was found to be relatively high with little seasonal fluctuation. Mineral nutrient status was characterised by particularly low phosphorus, below optimal nitrogen, ample calcium and potassium and a soil pH which was only mildly acid. The physiological characteristics of C. dissectum were determined by a series of controlled experiments. The species exhibited a high water requirement but was relatively tolerant of drought stress and prolonged dehydration. It was demonstrated that C. dissectum is well adapted to a low phosphorus environment, is tolerant of nitrogen levels considered below optimum for many plants and is relatively tolerant of shade. It can also recover from partial or total defoliation in a relatively short period of time without any loss in plant mass or carbohydrate reserves. From the physiological characteristics, it was concluded that C. dissectum conforms to the "stress-tolerant competitor" functional type. It was also concluded that the decline of the species is directly related to loss of habitat as a result of its degree of specialism and specific niche requirement. The implications for management of existing sites and restoration of degraded sites is discussed and an outline model of appropriate management actions is presented.
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Armstrong, Neil. "The physical activity patterns and cardiorespiratory fitness of children aged 11 to 16 years : with reference to sex, chronological age, sexual maturity and selected coronary risk factor variables." Thesis, University of Exeter, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329840.
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Cunha, Caio Dorneles. "Controlador em modo dual adaptativo robusto - DMARC." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15122.
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Previous issue date: 2008-01-24The so-called Dual Mode Adaptive Robust Control (DMARC) is proposed. The DMARC is a control strategy which interpolates the Model Reference Adaptive Control (MRAC) and the Variable Structure Model Reference Adaptive Control (VS-MRAC). The main idea is to incorporate the transient performance advantages of the VS-MRAC controller with the smoothness control signal in steady-state of the MRAC controller. Two basic algorithms are developed for the DMARC controller. In the first algorithm the controller's adjustment is made, in real time, through the variation of a parameter in the adaptation law. In the second algorithm the control law is generated, using fuzzy logic with Takagi-Sugeno s model, to obtain a combination of the MRAC and VS-MRAC control laws. In both cases, the combined control structure is shown to be robust to the parametric uncertainties and external disturbances, with a fast transient performance, practically without oscillations, and a smoothness steady-state control signal
Neste trabalho ? apresentada uma proposta de um controlador, denominado Controlador em Modo Dual Adaptativo Robusto (DMARC), que estabelece uma liga??o entre um controlador adaptativo por modelo de refer?ncia (MRAC) e um controlador adaptativo por modelo de refer?ncia e estrutura vari?vel (VS-MRAC). A id?ia b?sica ? incorporar as vantagens de desempenho transit?rio do controlador VS-MRAC com as propriedades de regime permanente do controlador MRAC convencional. S?o desenvolvidos dois algoritmos b?sicos para o controlador DMARC. No primeiro o ajuste do controlador ? feito, em tempo real, atrav?s da varia??o de um par?metro na lei de adapta??o. No segundo algoritmo a lei de controle ? gerada, utilizando o modelo Takagi-Sugeno da l?gica nebulosa, para obter uma composi??o ponderada das leis de controle do MRAC e do VS-MRAC. Em ambos os casos, o esquema combinado de controle ? mostrado ser robusto ?s incertezas param?tricas e perturba??es externas, al?m de apresentar um desempenho r?pido e pouco oscilat?rio durante o transit?rio e um sinal de controle suave em regime permanente
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Silva, Andre Tavares da. "Controle de posi??o com restri??o ? orienta??o de um Ve?culo A?reo N?o-Tripulado tipo Quadrirrotor." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15493.
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Previous issue date: 2014-01-24Quadrotors aircraft are composed by four propellers mounted on four engines on a cross or x disposition, and, in this structure, the engines on the same arm spin in the same direction and the other arm in the opposite direction. By rotating each helix generates vertical upward thrust. The control is done by varying the rotational speed of each motor. Among the advantages of this type of vehicle can cite the mechanical simplicity of construction, the high degree of maneuverability and the ability to have vertical takeoffs and landings. The modeling and control of quadrirrotores have been a challenge due to problems such as nonlinearity and coupling between variables. Several strategies have been developed to control this type of vehicle, from the classical control to modern. There are air surveillance applications where a camera is fixed on the vehicle to point forward, where it is desired that the quadrotor moves at a fixed altitude toward the target also pointing forward, which imposes an artificial constraint motion, because it is not desired that it moves laterally, but only forwards or backwards and around its axes . This restriction is similar to the naturally existing on robots powered by wheels with differential drive, which also can not move laterally, due to the friction of the wheels. Therefore, a position control strategy similar to that used in this type of robot could be adapted for aerial robots like quadrotor. This dissertation presents and discusses some strategies for the control of position and orientation of quadrotors found in the literature and proposes a strategy based on dynamic control of mobile robots with differential drive, called the variable reference control. The validity of the proposed strategy is demonstrated through computer simulations
Quadrirrotores s?o ve?culos a?reos compostos por quatro h?lices montadas sobre quatro motores em uma disposi??o em cruz ou x, sendo que, nessa estrutura, os motores sobre o mesmo bra?o giram no mesmo sentido e os do outro bra?o em sentido oposto. Ao girar, cada h?lice gera empuxo vertical para cima. O controle ? feito variando-se a velocidade de rota??o de cada motor. Dentre as vantagens desse tipo de ve?culo pode-se citar a simplicidade mec?nica de constru??o, o alto grau de manobrabilidade que possui e a capacidade de pousos e decolagens verticais. A modelagem e o controle de quadrirrotores tem sido um desafio devido a problemas como n?o-linearidades e acoplamento entre vari?veis. V?rias estrat?gias j? foram desenvolvidas para o controle desse tipo de ve?culo, desde as de controle cl?ssico at? as mais modernas. H? aplica??es de supervis?o a?rea em que uma c?mera ? fixada no ve?culo de forma a apontar para a frente, onde ? desejado que o quadrirrotor procure se movimentar a uma altitude fixa em dire??o ao alvo tamb?m apontando para a frente, o que imp?e uma restri??o artificial de movimento, pois n?o ? desejado que se movimente lateralmente, mas para frente ou para tr?s e que gire ao redor dos seus eixos. Tal restri??o ? semelhante ?quela existente de maneira natural em rob?s movidos a rodas com acionamento diferencial, que tamb?m n?o podem se movimentar lateralmente, mas devido ao atrito das rodas. Portanto, uma estrat?gia de controle de posi??o semelhante ? usada nesse tipo de rob?s poderia ser adaptada para rob?s a?reos do tipo quadrirrotor. Este trabalho apresenta e discute algumas estrat?gias de controle de posi??o e orienta??o de quadrirrotores encontradas na literatura e prop?e uma estrat?gia baseada no controle din?mico de rob?s m?veis com acionamento diferencial, o chamado controle por refer?ncia vari?vel. A validade da estrat?gia proposta ? comprovada atrav?s de simula??es computacionais
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Bragança, Rosenbergue. "Estudo comparativo da estimativa da evapotranspiração de referência para três localidades no Estado do Espírito Santo." Universidade Federal do Espírito Santo, 2007. http://repositorio.ufes.br/handle/10/6575.
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Previous issue date: 2007-03-30O presente trabalho teve por objetivo realizar um estudo das equações empíricas para estimativa da evapotranspiração de referência em comparação ao método padrão Penman-Monteith FAO 56 para as condições climáticas dos municípios de Sooretama, Cachoeiro de Itapemirim e Venda Nova do Imigrante localizados, respectivamente, nas regiões Norte, Sul e Serrana do Estado do Espírito Santo. Foram utilizadas as variáveis climáticas referentes ao período chuvoso (outubro, novembro e dezembro) do ano de 2005 e do período seco (junho julho e agosto) do ano de 2006, obtidas via plataforma de dados do CPTEC - INPE provenientes das estações automatizadas agrometeorológicas códigos nº 31957, 31958 e 31959, respectivamente. Para comparar os valores de ET0 estimados por meio das equações empíricas com os do método padrão Penman-Monteith (FAO56), foram considerados os parâmetros da equação de regressão (β0, β1), coeficiente de determinação (r²), coeficiente de correlação (r), estimativa do erro padrão (EEP), índice de concordância (d), índice de confiança ou desempenho (c), nas escalas diária, três, cinco e sete dias, para os meses estudados nas três localidades. Baseando-se nas condições climáticas de onde se realizou o trabalho e nos índices e parâmetros obtidos , tanto no período chuvoso (outubro, novembro e dezembro de 2005) quanto no seco (junho, julho e agosto de 2006), os melhores métodos foram: xvii) Penman (48) Original ( c médio = 0,94), FAO24 Penman Mod.(c médio = 0,93), FAO24 BC (c médio = 0,95), classificando-os com Ótimo desempenho, ii) Priestley- Taylor (PT) ( c médio = 0,90), Turc(61) (c médio = 0,88) e Makkink (Mk) (c médio = 0,88), classificando-os com desempenho Mbom, e iii) apresentando-se como pior método o de Hargreaves-Samani (HS) ( c médio = 0,45), classificando-o com desempenho Sofrível.
The present work had as objective to accomplish a study of the empiric equations for estimate of the reference evapotranspiration in comparison with the standard method Penman-Monteith FAO 56 for the climatic conditions of the municipal districts of Sooretama, Cachoeiro of Itapemirim and New Sale of the Immigrant located, respectively, in the areas North, South and Highland of Espírito Saint State. The climatic variables were used regarding to the rainy period (October, November and December) of the year of 2005 and of the dry period (June, July and August) of the year of 2006, obtained through platform of data of CPTEC - coming INPE of the stations automated agrometeorological codes no. 31957, 31958 and 31959, respectively. To compare the values of dear ET0 through the empiric equations with the one of the standard method Penman-Monteith (FAO56) the parameters of the regression equation were considered (ß0, ß1), determination xviii coefficient (r²), correlation coefficient (r), estimate of the standard mistake (EEP), agreement index (d), trust index or acting (c), in the scales daily rate, three, five seven days, for the months studied at the three places. Basing on the climatic conditions from where the work took place and in the indexes and obtained parameters, so much in the rainy period (October, November and December of 2005) as in the dry (June, July and August of 2006), the best methods were: i) Penman (48) Original (medium c = 0,94), FAO24 Penman Mod. (medium c = 0,93), FAO24 BC (medium c = 0,95), classifying them with Great acting, ii) Priestley-Taylor (PT) (medium c = 0,90), Turc(61) (medium c = 0,88) and Makkink (Mk) (medium c = 0,88), classifying them with acting Good acting, and iii) coming as worse method the one of Hargreaves-Samani (HS) (medium c = 0,45), classifying it with Bearable acting.
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Beluský, Tomáš. "Detekce genomových variací." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2013. http://www.nusl.cz/ntk/nusl-236397.
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An influence of variations in human genome is perceptible at a first glance on human itself to see differences between the individuals and entire populations. Also, behavior or probability of certain diseases are influenced in large way by differences at genome's level. This work presents methods for detecting variations in the human genome that were developed after an arose of the second-generation sequencing technologies. A new tool that combines read pair and split read methods, with information about a depth of coverage was also designed and implemented. The tool was tested on simulated and real data and compared with a reference outputs.
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Krummenauer, Alex. "Desenvolvimento e validação de metodologia analítica para análise de aços por espectrometria de fluorescência de raios X por dispersão de energia (EDXRF)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/178232.
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O desenvolvimento e validação de métodos analíticos é um procedimento necessário quando um método não normalizado é utilizado por um laboratório de ensaios. A validação de métodos também é um requisito específico da norma ABNT NBR ISO/IEC 17025, que determina os requisitos gerais para a competência dos laboratórios de ensaio e calibração. O objetivo da validação é demonstrar que o método analítico, nas condições em que é executado, produz resultados com a exatidão requerida. O Laboratório de Corrosão, Proteção e Reciclagem de Materiais (LACOR), da UFRGS, tem o ensaio de determinação de metais por fluorescência de raios X, acreditado pelo CGCRE/INMETRO, conforme ABNT NBR ISO/IEC 17025. O ensaio é feito usando o método de espectrometria de fluorescência de raios X por dispersão de energia (EDXRF). Este método, contudo, não é normalizado e, portanto, o mesmo foi validado, neste trabalho de pesquisa, para atender a este requisito. A validação foi feita com base no documento orientativo DOQ-CGCRE-08 e no guia EURACHEM. Os parâmetros de validação, para o ensaio quantitativo por EDXRF, que foram calculados neste trabalho são: seletividade; limite de detecção (LD) e limite de quantificação (LQ); linearidade e faixa de trabalho; veracidade de medição (tendência, erro normalizado, Z-score e comparação com método de referência) e precisão (repetibilidade, precisão intermediária e reprodutibilidade). Além disso, foi desenvolvida uma metodologia de cálculo de incerteza de medição para o ensaio por EDXRF Os resultados obtidos neste estudo demonstram que o método EDXRF, usado na determinação de metais em aços, é um método não normalizado validado e compatível com os resultados obtidos com os métodos de referência: espectrometria de fluorescência de raios X por dispersão de comprimento de onda (WDXRF), fotométricos e espectrometria de absorção atômica (AAS). Inclusive, o WDXRF é um método de referência usado em muitas normas internacionais, que descrevem métodos de análise de aços por fluorescência de raios X, como ASTM E572 ou ASTM E1085. O estudo desenvolvido nesta dissertação permitiu que o LACOR mantivesse sua acreditação no ensaio de determinação de metais por fluorescência de raios X, na avaliação do CGCRE/INMETRO, no presente ano. Outros frutos deste trabalho foram a confecção das curvas de calibração do espectrômetro NITON XL3t GOLDD+ e a revisão do procedimento de ensaio, onde esses novos conhecimentos sobre a técnica EDXRF foram aplicados. Futuramente, este trabalho pode ser usado por outros pesquisadores para desenvolver estudos em outras matrizes metálicas, como cobre, alumínio, titânio ou níquel, e, também, em outras áreas de aplicação como jóias, reciclagem de materiais metálicos ou, até mesmo, para análise elementar de resíduos retidos em membranas de troca iônica.The development and validation of analytical methods is a required procedure when a non-standard method is used by a testing laboratory. Method validation is also a specific requirement of the ABNT NBR ISO / IEC 17025, which determines the general requirements for the competence of testing and calibration laboratories. The purpose of validation is to demonstrate that the analytical method, under the conditions in which it is performed, produces results with the required accuracy. The Corrosion, Protection and Recycling Materials Laboratory (LACOR), at UFRGS, has the X-ray fluorescence metal analysis, accredited by CGCRE / INMETRO, according to ABNT NBR ISO / IEC 17025. The test is performed using Energy Dispersive X-Ray Fluorescence spectrometry, EDXRF method. This method, however, is not standardized; therefore, it was validated in this research to meet this requirement. The validation was based on the DOQ-CGCRE-08 document and the EURACHEM guide. The method performance calculated in this study for quantitative testing by EDXRF are: selectivity; limit of detection (LOD) and limit of quantification (LOQ); linearity and working range; trueness (bias, normalized error, Z-score and comparison with reference method) and precision (repeatability, intermediate precision and reproducibility). In addition, a measurement uncertainty calculation methodology was developed for the EDXRF testing The results obtained in this study demonstrate that the EDXRF method, used in the determination in the chemical analysis of steels, is a validated non-standard method and compatible with the results obtained with the reference methods: Wavelength Dispersive X-Ray Fluorescence spectrometry (WDXRF), photometric and atomic absorption spectrometry (AAS). In addition, WDXRF is a reference method used in many international standards, which describes analysis of steels by X-ray fluorescence spectrometry such ASTM E572 or ASTM E1085. The study developed in this dissertation allowed LACOR to maintain its accreditation in the test of metal by X-ray fluorescence analysis, in the CGCRE / INMETRO audit, this year. Other fruits of this work were the preparation of calibration curves of NITON XL3t GOLDD + spectrometer and complete revision of testing procedure, where this new knowledge about the EDXRF technique was applied. In the future, this work can be used by other researchers to develop studies in other base metals such as copper, aluminum, titanium or nickel, and also in other areas of application such as jewelry, recycling of metallic materials or even for analysis elemental residues retained in ion exchange membranes.
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Pereira, Nuno Ruben Ferreira. "Design of Analog-to-Digital Converters with Embedded Mixing for Ultra-Low-Power Radio Receivers." Doctoral thesis, 2019. http://hdl.handle.net/10362/91170.
Full textAbstract:
In the field of radio receivers, down-conversion methods usually rely on one (or more)
explicit mixing stage(s) before the analog-to-digital converter (ADC). These stages not
only contribute to the overall power consumption but also have an impact on area and can
compromise the receiver’s performance in terms of noise and linearity. On the other hand,
most ADCs require some sort of reference signal in order to properly digitize an analog
input signal. The implementation of this reference signal usually relies on bandgap
circuits and reference buffers to generate a constant, stable, dc signal. Disregarding this
conventional approach, the work developed in this thesis aims to explore the viability
behind the usage of a variable reference signal. Moreover, it demonstrates that not only
can an input signal be properly digitized, but also shifted up and down in frequency,
effectively embedding the mixing operation in an ADC. As a result, ADCs in receiver
chains can perform double-duty as both a quantizer and a mixing stage. The lesser known
charge-sharing (CS) topology, within the successive approximation register (SAR) ADCs,
is used for a practical implementation, due to its feature of “pre-charging” the reference
signal prior to the conversion. Simulation results from an 8-bit CS-SAR ADC designed in
a 0.13 μm CMOS technology validate the proposed technique.
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Černáčková, Júlia. "Žánrově podmíněné variace kohezních prostředků v japonštině." Master's thesis, 2017. http://www.nusl.cz/ntk/nusl-369832.
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e Abstract (in English): The aim of the present thesis is to investigate the differences in cohesive devices use in selected Japanese texts of different genes. The English conception of cohesion (based on Halliday and Hasan's "Cohesion in English") is applied to Japanese with several slight modifications and the following devices and their sub-types are examined: reference, substitution, ellipsis, conjunction and lexical cohesion. Using three texts of different genres- book review, newspaper article and a fictional narrative- the assumption of genre-conditioned variation of cohesive devices employment is scrutinized and the distinctions and similitudes are described. The first, general theory part of the thesis presents the basic concepts related to cohesion. In the second part, both English and Japanese perspectives on cohesion are presented. Subsequently, the English (Halliday and Hasan's) concept is evaluated as a more pertinent one and applied in the Japanese textual environment. Subsequent parts of the paper present research questions as well as supporting arguments to the examined underlying assumption and provide an overview of methodology applied in analysis of the selected texts. In the final part, the results concerning cohesion articulation in various genres in Japanese obtained from the analysed...
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CHA, ZHONG-WEI, and 查忠偉. "Design of model reference adaptive control system with state variable filter and variable structure mechanism." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/56054478995709922348.
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Pfeiffer, Phillip E. "Dependence-based representations for programs with reference variables." 1991. http://catalog.hathitrust.org/api/volumes/oclc/25637079.html.
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Thesis (Ph. D.)--University of Wisconsin--Madison, 1991.Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 287-303) and index.
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Kang, Yun-Shao, and 康云韶. "The Effects of Reference Group Behavior and Reference Price on Purchase Intention – Self-Construal as Moderating Variable." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/746f2w.
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碩士大同大學
事業經營學系(所)
106
As we live in all kinds of different groups, our relationships with others are impacted that influences our behavior judgment and our purchase intentions are all connected among the groups. Today, E-commerce, mobility, easy-shopping, delivery, commerce information, AI, Big Data analysis have been developing, they provide people great convenience to our daily life in particular in purchase decision. The research regarding the effect of reference group behavior and reference price on purchase behavior have been going on for decades. Searching out all studies in our country and the world, there is few that are focus on self-construal as moderating variable. The objective of this research is not only on the effect of reference group behavior and reference price on purchase intention, also the moderating impact of self-construal. The college students in Tatung University are the subjects by applying the experiment. This study adopts a 2 (reference group: purchase and not purchasing) x 3 (reference price: external reference price greater than internal reference price, external reference price equal to internal reference price, external reference price less than internal reference price) x 2 (Self-construal: independent self-construal / interdependent self-construal), total 322 subjects experiment design. The result finds that 1. Reference group behavior is positive impact on purchase intention. 2. Reference price is positive impact on purchase intention. 3. Self-construal has no moderating effect on purchase intention.
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JIAN, JIANG-RU, and 簡江儒. "A new approach to model reference adaptive control using variable structure design." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/93819186377359759651.
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Chou, Chien-Hsin, and 周建興. "Design of Model Reference Adaptive Variable Structure Controllers for Uncertain Dynamic Systems." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/62699396089811646876.
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Teng, Fei-Jen, and 鄧斐仁. "Model Reference Adaptive Predictive Control of a Variable-Frequency Oil-Cooling Machine." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/69283038753726509642.
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碩士國立中興大學
電機工程學系
90
This thesis develops methodologies and techniques for model reference adaptive predictive control laws design and implementation of a DSP-based controller for a variable-frequency oil-cooling machine. The plant is well approximated by a first-order system model with time delay and its system parameters are estimated using the recursive least-squares estimation method. In order to obtain a low-cost, real-time and high-performance controller, we build a stand-alone control architecture using a powerful TMS320F243 DSP single chip with associated peripherals. To achieve satisfactory control performance specifications, the thesis proposes two model reference adaptive predictive control strategies, model reference indirect self-tuning predictive control and direct self-tuning model following predictive control. Experimental results show that both the two proposed control methods together with the DSP-based controller’s prototype have been proven to work well for the machine under set-point changes, fixed heat loads and heat load changes.
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WU, A.-CHENG, and 吳阿城. "Decentralized model reference adaptive control for a class of interconnected dynamic systems using variable structure design." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/67621626332857289580.
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Chen, I.-Wen, and 陳藝文. "Alignment for Array Reference with Linear Subscripts in Two Index Variables or Quadric Subscripts." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/40242162187253761453.
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碩士國立成功大學
資訊工程學系
86
In massively parallel processing systems，data communication cost at execution time is the determining factor to program performance。To reduce data communication overhead considerable efforts have been paid on the methods of data distribution and data alignment。In this thesis，we focus on the study of data alignment methods。We first introduce loop index domain alignment with CAG (Component Affinity Graph) scheme and present elementary matrix techniques for determining communication-free alignment of code and data proposed by Bau et al。 We then develop two new alignment functions that can be applied toward determining communication-free data alignment for array references with linear scripts in two index variables and quadric subscripts，respectively。In order to gain the least communication cost at execution time，we also propose some steps to remove unsatisfied constraints and preserve the constraints that have higher communication overhead。Meanwhile，we also proffer method to resolve the problem that same/different arrays have several reference functions。Finally the feasibility of our proposed alignment model is also verified via benchmark codes in PVM (Parallel Virtual Machine) environment。
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Levy, Levy Warren. "Modelling and simulation of induction motors for variable speed drives, with special reference to deep bar and saturation effects." Thesis, 1990. https://hdl.handle.net/10539/24649.
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A thesis submitted to the Faculty of Engineering, University of the Witwatersrand,
Johannesburg, in fulfillment of the requirements for the Degree of Doctor of
Philosophy.Variable speed motors are achieved by varying the voltage of a DC machine or by varying the frequency of an AC machine, the former method being the simpler of the two. DC motors have the major disadvantage of brushes and commutators which require regular downtime for maintenance, a fact already recognised by Tesla [1] in 1888. Thus the AC motor, in particular the induction motor, is of a more rugged design and does not suffer from the commutator problem of its DC counterpart. Recent advances in the technology of the power electronics used to supply a variable frequency to the motor has allowed the induction motor to be a viable alternative to the DC motor in variable speed applications. Problems have been encountered in industry when an inverter is injudiciously selected to be combined with a motor. Such problems were highlighted by difficulties being experienced with some 400 kW inverter drives. The inverters had been bought from one supplier and the motors from another. When this system was coupled together, there was excessive heating in the motors and the overall plant was only able to operate well below its capacity, incurring a substantial weekly loss of income. The motor and inverter were evidently incompatible, and since the inverter could not be modified, the motor was redesigned to make it less susceptible to the harmonics present in the inverter waveform, These problems have led to the development of a variable speed drive simulation package at the University for use by the local industry which can accurately model the complete system of inverter, motor and its associated load. It is envisaged that this package could be used to predict the performance of a drive system and highlight problems that may occur. To be able to do this, an accurate model of the motor is required. This investigation gives the development of an induction motor model which is suitable . for variable speed drive system simulations. The model accounts for the deep bar effect by using lumped parameter circuits and includes saturation of the leakage paths using only information which is typically available from motor design data. A complete analysis is given of the different lumped parameter models and their suitability for use in this application. The thesis also shows the utilisation of the deep bar model to simulate reswitching transients and double cage motors. The author hopes that the models used in the simulation package wallow industry to predict problems prior to their occurrence, alter the designs and thereby avoid costly remanufacture of the system.
Andrew Chakane 2018
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Pandharpurkar, Jayashree D. "A study of the development of character in children with reference to certain cognitive and affective variables." Thesis, 1993. http://hdl.handle.net/2009/4430.
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