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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.
251

Μοντελοποίηση και έλεγχος ισχύος αιολικών συστημάτων με ασύγχρονη μηχανή διπλής τροφοδοσίας

Χριστοπούλου, Στέλλα 19 May 2011 (has links)
Αντικείμενο της παρούσας διπλωματικής εργασίας είναι η προσομοίωση της λειτουργίας μιας ανεμογεννήτριας (Α/Γ) μεταβλητής ταχύτητας με γεννήτρια επαγωγής διπλής τροφοδότησης (ΓΕΔΤ) καθώς επίσης και ο έλεγχος της γωνίας βήματος των πτερυγίων. Η προσομοίωση γίνεται με τη βοήθεια του προγράμματος Matlab/Simulink. Αναλυτικότερα στο Κεφάλαιο1, γίνεται εισαγωγή στις ανανεώσιμες πηγές ενέργειας (ΑΠΕ). Αναφέρονται τα είδη, τα πλεονεκτήματα και ο ενεργειακός τους ρόλος στην παραγωγή της ηλεκτρικής ενέργειας σε εθνικό επίπεδο. Από τις ΑΠΕ, αναλύεται η αιολική ενέργεια. Γίνεται μια σύντομη ιστορική αναδρομή και παρουσιάζεται η χρησιμότητα της, τα προβλήματα που προκύπτουν από την σύνδεση Α/Γ στο δίκτυο και η θέση της στο παγκόσμιο ενεργειακό επίπεδο. Στο Κεφάλαιο 2, γίνεται παρουσίαση των μηχανών επαγωγής. Συγκεκριμένα, παρουσιάζεται η μαθηματική θεμελίωση της θεωρίας των μετασχηματισμών σε πλαίσιο αναφοράς δύο κάθετων αξόνων που περιστρέφεται με αυθαίρετη ταχύτητα και η μοντελοποίηση (δυναμικό μοντέλο) των ασύγχρονων ηλεκτρικών μηχανών επαγωγής. Στο Κεφάλαιο 3,γίνεται μια γενική παρουσίαση των αιολικών συστημάτων. Περιγράφονται τα δομικά στοιχεία της Α/Γ, η αεροδυναμική μετατροπή της ενέργειας του ανέμου σε ηλεκτρική, τα διάφορα συστήματα Α/Γ που χρησιμοποιούνται και δίνεται το μαθηματικό μοντέλο της γεννήτριας επαγωγής διπλής τροφοδότησης (ΓΕΔΤ). Στο Κεφάλαιο 4,παρουσιαζεται η συνολική στρατηγική ελέγχου Α/Γ μεταβλητής ταχύτητας με ΓΕΔΤ, η οποία περιλαμβάνει τον αεροδυναμικό έλεγχο της Α/Γ και τον ηλεκτρικό έλεγχο της γεννήτριας επαγωγής διπλής τροφοδότησης στην πλευρά του δρομέα (μηχανής) και στην πλευρά του στάτη (δικτύου). Στο Κεφάλαιο 5, παρουσιάζονται τα αποτελέσματα από δοκιμές που έγιναν με το μοντέλο προσομοίωσης που αναπτύχθηκε στο κεφάλαιο 4, ως προς την απόκριση του συστήματος υπό την επίδραση διαφόρων αλλαγών του ανέμου και μονοφασικού βραχυκυκλώματος στην γραμμή μεταφοράς. Τέλος, παρατίθενται γενικά σχόλια και συμπεράσματα της εργασίας για τη λειτουργία και απόκριση του συστήματος που αναπτύχθηκε. / The subject of this thesis is the analysis and simulation of a variable speed, pitch controlled wind turbine equipped with a doubly fed induction generator (DFIG). Simulation was made with the use of the software Matlab/Simulink©, ed. 7.0.1. Analytically, Chapter 1 is an introduction to renewable energy sources (RES). Are reported the types, the advantages and their energy role in the production of electric energy at national level. By the RES, the wind energy is analyzed. Begins a short historical retrospection and is presented its usefulness, the problems that result from connection in the electrical network and its place at the world energy level. Chapter 2, presents the induction machines. Specifically, are presented the mathematical base of theory of transformation to a reference frame which rotates at an arbitrary angular velocity and the modelling (dynamic model) of the induction machines. Chapter 3, is a general presentation of aeolian systems. The structural elements of wind turbine, the aerodynamic transformation of wind energy in electric and the various wind turbine systems that are used, are described. Moreover, the dynamic model of a double fed induction generator (DFIG) is given. In Chapter 4, the overall control strategy of variable speed doubly fed induction generator wind turbine is presented, which includes the aerodynamic control of the wind turbine and the electric control of the DFIG both at rotor side (machine) and at the stator side (grid). In Chapter 5, the results from the simulations of the developed model under different wind conditions and a fault on the 25 KV system are presented. Finally, general comments and conclusions on the operation and the results of the developed system are made.
252

Equilíbrio de força muscular e retardo eletromecânico na articulação do ombro entre atletas de diferentes modalidades esportivas

Minozzo, Felipe January 2017 (has links)
O objetivo deste estudo foi avaliar e comparar o equilíbrio de força muscular e o tempo de retardo eletromecânico na articulação do ombro entre atletas de diferentes modalidades esportivas, os quais utilizam predominantemente rotações internas e externas de ombro durante as suas práticas esportivas. Fizeram parte do estudo 41 sujeitos do sexo masculino, sendo 15 atletas profissionais de Voleibol (24,07 ± 5,13 anos; 91,60 ± 11,67 kg; 198,47 ± 5,90 cm), 14 atletas profissionais de Judô (26,64 ± 7,30 anos; 87,36 ± 15,20 kg; 178,07 ± 6,90 cm) e 12 atletas universitários de Handebol (23,17 ± 4,70 anos; 84,75 ± 13,50 kg; 182,08 ± 6,20 cm). Para a mensuração de força máxima, de diferença contralateral (i.e. lados direito vs. esquerdo) e para o cálculo das razões entre rotação interna e externa de ombro, os participantes realizaram testes de dinamometria isocinética em condições isométricas e isocinéticas. Durante os testes isométricos foi realizada a coleta do sinal eletromiográfico dos músculos peitoral maior e infraespinal, o que possibilitou o cálculo do retardo eletromecânico. Os resultados demonstram que atletas de Judô possuem força isométrica de rotação interna de ombro significativamente (p<0,01) maior quando comparados com atletas de Voleibol e de Handebol. Atletas de Judô apresentam valores de razão agonista/antagonista isométrica de membro direito significativamente (p<0,03) inferiores aos grupos Voleibol e Handebol, bem como significativamente (p<0,01) inferiores ao grupo Voleibol em relação ao membro esquerdo O tempo de retardo eletromecânico apresentou diferenças entre os grupos somente na rotação externa, em que o grupo Voleibol apresentou valores do membro direito significativamente (p<0,01) mais curtos quando comparados com o grupo Handebol e valores de membro esquerdo significativamente (p<0,01) mais curtos quando comparados com os grupos Handebol e Judô. Picos de torque isocinéticos apresentaram diferença somente para rotação interna de membro direito, em que o grupo Judô apresentou valores significativamente (p<0,001) maiores quando comparados com o grupo Voleibol. Já para membro esquerdo, detectou-se diferença significativa (p<0,01) no ângulo de pico de torque de rotação interna de membro esquerdo entre o grupo Judô e Handebol. Os resultados do estudo permitem concluir que a prática de cada modalidade esportiva avaliada neste estudo promoveu adaptação dos músculos do ombro, de acordo com a demanda da modalidade esportiva. Assim, atletas de Judô necessitam realizar reforço dos músculos rotadores externos do ombro, tanto concêntrica quanto excentricamente, visto o desequilíbrio muscular causado pela especificidade da modalidade. Por outro lado, atletas de Voleibol apresentam satisfatório equilíbrio muscular na articulação do ombro por conta de altos níveis de força excêntrica de rotação externa exigidos na prática deste esporte; além disso, os curtos períodos de tempo de retardo eletromecânico apresentados por estes atletas reforçam a constatação de equilíbrio desta articulação. Atletas de Handebol apresentam satisfatório equilíbrio muscular na articulação do ombro, entretanto apresentam valores altos de retardo eletromecânico, sendo indicado que estes atletas realizem reforço de rotação externa de ombro, sobretudo em velocidade elevada, com o objetivo de diminuir o tempo necessário para ativar estes grupos musculares. / The purpose of this study was to evaluate and compare the muscular balance and the electromechanical delay time of the shoulder joint between athletes of different sports modalities who use predominantly internal and external rotations of the shoulder. The study consisted of a total of 41 male subjects, of whom 15 were professional Volleyball players (n = 15, 24.07 ± 5.13 years, 91.60 ± 11.67 kg, 198.47 ± 5.90 cm), 14 professional Judo athletes (26.64 ± 7.30 years, 87.36 ± 15.20 kg, 178.07 ± 6.90 cm) and 12 university Handball athletes (23.17 ± 4.70 years, 84.75 ± 13.50 kg, 182.08 ± 6.20 cm). To evaluate peak torque, upper limb side-to-side asymmetry and for the calculation of conventional and functional ratios, all subjects performed isokinetic dynamometry tests under isometric and dynamic conditions. During the isomeric tests, the electromyographic signal was collected from the pectoralis major and infraspinal muscles, which allowed the calculation of the electromechanical delay. The results demonstrate that Judo athletes have internal shoulder rotation isometric strength significantly (p<0.01) higher when compared to Volleyball and Handball athletes. Judo athletes presented isometric agonist/antagonist ratio of right limb significantly (p<0.03) lower than the Volleyball and Handball groups, as well as significantly (p<0.01) lower than the Volleyball group in relation to the left limb. The electromechanical delay time presented differences between the groups only in the external shoulder rotation, which the Volleyball group presented significantly lower values of right limb (p<0.01) when compared to the Handball group and left limb times significantly (p<0.01) shorter when compared with the Handball and Judo groups Dynamic peak torque presented difference only for internal shoulder rotation of the right limb, which the Judo group presented values significantly (p<0.001) higher when compared to the Volleyball group. For the left upper limb, a significant difference (p<0.01) was detected in the peak torque angle of internal shoulder rotation between the Judo and Handball groups. The results of the study allow to considering that the practice of each evaluated sports modalities adapts the shoulder of its athletes in different ways. Judo athletes need to perform external shoulder rotation muscular strengthening, both in concentric and eccentric modes due to muscle imbalance caused by the specificity of the modality. Volleyball athletes have reasonable muscle balance in the shoulder joint due to the high levels of eccentric strength of external rotation, in addition the short time periods of electromechanical delay presented by these athletes reinforce even more the balance of this joint. Handball athletes have reasonable muscle balance in the shoulder joint; however, they presented high values of electromechanical delay, so it is indicated that these athletes need to perform muscular strengthening of external rotation of the shoulder in order to reduce the time required to activate these muscles.
253

Equilíbrio de força muscular e retardo eletromecânico na articulação do ombro entre atletas de diferentes modalidades esportivas

Minozzo, Felipe January 2017 (has links)
O objetivo deste estudo foi avaliar e comparar o equilíbrio de força muscular e o tempo de retardo eletromecânico na articulação do ombro entre atletas de diferentes modalidades esportivas, os quais utilizam predominantemente rotações internas e externas de ombro durante as suas práticas esportivas. Fizeram parte do estudo 41 sujeitos do sexo masculino, sendo 15 atletas profissionais de Voleibol (24,07 ± 5,13 anos; 91,60 ± 11,67 kg; 198,47 ± 5,90 cm), 14 atletas profissionais de Judô (26,64 ± 7,30 anos; 87,36 ± 15,20 kg; 178,07 ± 6,90 cm) e 12 atletas universitários de Handebol (23,17 ± 4,70 anos; 84,75 ± 13,50 kg; 182,08 ± 6,20 cm). Para a mensuração de força máxima, de diferença contralateral (i.e. lados direito vs. esquerdo) e para o cálculo das razões entre rotação interna e externa de ombro, os participantes realizaram testes de dinamometria isocinética em condições isométricas e isocinéticas. Durante os testes isométricos foi realizada a coleta do sinal eletromiográfico dos músculos peitoral maior e infraespinal, o que possibilitou o cálculo do retardo eletromecânico. Os resultados demonstram que atletas de Judô possuem força isométrica de rotação interna de ombro significativamente (p<0,01) maior quando comparados com atletas de Voleibol e de Handebol. Atletas de Judô apresentam valores de razão agonista/antagonista isométrica de membro direito significativamente (p<0,03) inferiores aos grupos Voleibol e Handebol, bem como significativamente (p<0,01) inferiores ao grupo Voleibol em relação ao membro esquerdo O tempo de retardo eletromecânico apresentou diferenças entre os grupos somente na rotação externa, em que o grupo Voleibol apresentou valores do membro direito significativamente (p<0,01) mais curtos quando comparados com o grupo Handebol e valores de membro esquerdo significativamente (p<0,01) mais curtos quando comparados com os grupos Handebol e Judô. Picos de torque isocinéticos apresentaram diferença somente para rotação interna de membro direito, em que o grupo Judô apresentou valores significativamente (p<0,001) maiores quando comparados com o grupo Voleibol. Já para membro esquerdo, detectou-se diferença significativa (p<0,01) no ângulo de pico de torque de rotação interna de membro esquerdo entre o grupo Judô e Handebol. Os resultados do estudo permitem concluir que a prática de cada modalidade esportiva avaliada neste estudo promoveu adaptação dos músculos do ombro, de acordo com a demanda da modalidade esportiva. Assim, atletas de Judô necessitam realizar reforço dos músculos rotadores externos do ombro, tanto concêntrica quanto excentricamente, visto o desequilíbrio muscular causado pela especificidade da modalidade. Por outro lado, atletas de Voleibol apresentam satisfatório equilíbrio muscular na articulação do ombro por conta de altos níveis de força excêntrica de rotação externa exigidos na prática deste esporte; além disso, os curtos períodos de tempo de retardo eletromecânico apresentados por estes atletas reforçam a constatação de equilíbrio desta articulação. Atletas de Handebol apresentam satisfatório equilíbrio muscular na articulação do ombro, entretanto apresentam valores altos de retardo eletromecânico, sendo indicado que estes atletas realizem reforço de rotação externa de ombro, sobretudo em velocidade elevada, com o objetivo de diminuir o tempo necessário para ativar estes grupos musculares. / The purpose of this study was to evaluate and compare the muscular balance and the electromechanical delay time of the shoulder joint between athletes of different sports modalities who use predominantly internal and external rotations of the shoulder. The study consisted of a total of 41 male subjects, of whom 15 were professional Volleyball players (n = 15, 24.07 ± 5.13 years, 91.60 ± 11.67 kg, 198.47 ± 5.90 cm), 14 professional Judo athletes (26.64 ± 7.30 years, 87.36 ± 15.20 kg, 178.07 ± 6.90 cm) and 12 university Handball athletes (23.17 ± 4.70 years, 84.75 ± 13.50 kg, 182.08 ± 6.20 cm). To evaluate peak torque, upper limb side-to-side asymmetry and for the calculation of conventional and functional ratios, all subjects performed isokinetic dynamometry tests under isometric and dynamic conditions. During the isomeric tests, the electromyographic signal was collected from the pectoralis major and infraspinal muscles, which allowed the calculation of the electromechanical delay. The results demonstrate that Judo athletes have internal shoulder rotation isometric strength significantly (p<0.01) higher when compared to Volleyball and Handball athletes. Judo athletes presented isometric agonist/antagonist ratio of right limb significantly (p<0.03) lower than the Volleyball and Handball groups, as well as significantly (p<0.01) lower than the Volleyball group in relation to the left limb. The electromechanical delay time presented differences between the groups only in the external shoulder rotation, which the Volleyball group presented significantly lower values of right limb (p<0.01) when compared to the Handball group and left limb times significantly (p<0.01) shorter when compared with the Handball and Judo groups Dynamic peak torque presented difference only for internal shoulder rotation of the right limb, which the Judo group presented values significantly (p<0.001) higher when compared to the Volleyball group. For the left upper limb, a significant difference (p<0.01) was detected in the peak torque angle of internal shoulder rotation between the Judo and Handball groups. The results of the study allow to considering that the practice of each evaluated sports modalities adapts the shoulder of its athletes in different ways. Judo athletes need to perform external shoulder rotation muscular strengthening, both in concentric and eccentric modes due to muscle imbalance caused by the specificity of the modality. Volleyball athletes have reasonable muscle balance in the shoulder joint due to the high levels of eccentric strength of external rotation, in addition the short time periods of electromechanical delay presented by these athletes reinforce even more the balance of this joint. Handball athletes have reasonable muscle balance in the shoulder joint; however, they presented high values of electromechanical delay, so it is indicated that these athletes need to perform muscular strengthening of external rotation of the shoulder in order to reduce the time required to activate these muscles.
254

Estudo de aplicação de ferramentas numéricas ao problema de ressonância de ondas na operação de alívio lado a lado. / Study of application of numerical tools of the wave resonance problem in side-by-side offocading operation.

Raul Dotta 30 March 2017 (has links)
Este trabalho apresenta uma abordagem numérica com base em ensaios experimentais previamente realizados, direcionada ao problema de ressonância do campo de ondas em operações de alívio lado a lado (side by side). Os efeitos dessas interferências hidrodinâmicas são responsáveis por alterar drasticamente o campo de ondas em regiões de confino, gerando amplificação nos movimentos de primeira ordem e trazendo risco à operação. Este fenômeno está presente em diversas áreas da exploração e produção offshore e vem sendo o principal objeto de estudo nos últimos anos, principalmente em operações de alívio lado a lado, nos quais existe uma grande preocupação de colisão, rompimento dos cabos e integridade estrutural das defensas, devido à proximidade dos cascos. Neste contexto, devido à complexidade do problema, a modelagem numérica utilizada para interpretar o fenômeno de ressonância em softwares comerciais deve ser realizada com cautela, sendo que a utilização direta desta ferramenta gera amplificações equivocadas da superfície ressonante uma vez que esta resolução tem como base a teoria potencial. As diferenças observadas durante a comparação entre ensaios numéricos e experimentais são causadas em virtude da negligência na avaliação da dissipação de parte da energia das ondas ressonantes provocadas devido aos efeitos como viscosidade, vorticidade e turbulência do escoamento. Com o objetivo de analisar corretamente este fenômeno por meio de ensaios numéricos, uma maneira consiste na inclusão de adaptações no modelo para atingir os resultados desejáveis. Estas adaptações consistem na implementação de métodos artificiais, tais como os chamados \"Modos Generalizados\" e \"Praias Numéricas\", aplicados à região entre as embarcações com o intuito de amortecer as elevações irrealistas da superfície. Sendo assim, este trabalho abordará o problema de ressonância de ondas, investigando o desempenho de duas ferramentas numéricas para a sua predição, o WAMIT (Wave Analysis Massachusetts Institute of Technology) e o TDRPM (Time Domain Rankine Painel Method). Os resultados serão comparados com dados obtidos em um conjunto de ensaios em escala reduzida, realizado previamente no laboratório Tanque de Provas Numérico da USP (TPN). Dessa forma, o estudo dos fenômenos de ressonância será discutido, principalmente, em seu aspecto numérico, visando à verificação do desempenho do WAMIT e do TDRPM. / This work presents a numerical study based on previously conducted experimental studies, focused on the problem of resonance of the wave field in operations involving multi-body. The hydrodynamic interferences effects are responsible for drastically changing the wave field in confine regions, generating amplification of first order movements and bringing operational risk. This phenomenon is present in several areas of offshore exploration and production and has been the main object of study in recent years, mainly in side-by-side offloading operations, in which there is a great concern due to the risk of mooring lines breaking, damages to the fenders and also collision. In this context, due to the complexity of the problem, the numerical modeling used to evaluate the resonance phenomenon in commercial software becomes unsuitable, generating erroneous amplifications of the resonant surface since it is based on the potential theory. The differences observed during the comparisons between numerical and experimental tests are caused by negligence in the evaluation of the dissipation of part of the resonant wave energy caused by viscosity, vorticity and flow turbulence effects. In order to correctly analyze this phenomenon through numerical tests, one way is to include adaptations on the model to achieve the desired results. These adaptations consist of the implementation of artificial methods, such as \"Generalized Modes\" and \"Numerical Damping Zones\", applied to the region between the vessels in order to damp the unrealistic elevations of the surface. Thus, this study will approach the problem of gap wave resonance, investigating the performance of two numerical tools for its prediction, WAMIT (Wave Analysis Massachusetts Institute of Technology) and TDRPM (Time Domain Rankin Panel Method). The results will be compared with data obtained from a set of small scale tests previously performed at the Numerical Test Tank of USP laboratory (TPN). Therefore, the study of resonance phenomena will be discussed, mainly, in its numerical aspect, in order to verify the performance of WAMIT and TDRPM.
255

Effets de contexte et modulation des processus sociocognitifs via Internet / Context effects and modulation of sociocognitive processes on the Internet

Guegan, Jérôme 05 December 2012 (has links)
L’essor considérable d’Internet a permis l’émergence de nouveaux espaces d’échanges et d’interactions réunissant les individus à distance. Ces nouvelles formes d’interactions sociales ont conduit les chercheurs, dans le cadre des Communications Médiatisées par Ordinateur (CMO) à étudier la composante sociale des échanges en ligne, les spécificités et les conséquences de ce type d’interaction. Dans cette perspective, l’objectif de ce travail est d’examiner dans quelle mesure les spécificités des CMO – en premier lieu l’anonymat – peuvent moduler les perceptions sociales et les processus impliqués lors des interactions en ligne. Cette problématique concerne nombre de situations de communication et implique différents processus. De fait, le présent travail s’organise selon trois axes de recherche. Le premier axe aborde l’étude des perceptions groupales basées sur des appartenances circonscrites à un environnement virtuel. Le second axe s’intéresse à la modulation des perceptions de genre sur Internet, en tenant compte de la structure asymétrique de ces perceptions. Le troisième axe étudie la modulation des pressions normatives et des possibilités d’expression lors des CMO. Dans leur ensemble, ces travaux suggèrent que les CMO n’induisent pas un affaiblissement des facteurs sociaux, mais une modulation des processus en fonction des spécificités du contexte d’interaction. Les résultats de ces recherches sont discutés au regard notamment des théories de l’identité sociale, de l’auto-catégorisation et du modèle SIDE. / The growth of Internet allowed the emergence of new spaces of exchanges and social interaction between remote individuals. These new modalities of social interactions led the researchers, in the framework of Computer-Mediated Communication (CMC), to study the social component of online exchanges, characteristics and consequences of this type of interaction. In this perspective, the aim of this work is to examine how the characteristics of CMC - first anonymity - can modulate social perceptions and the processes involved in online interactions. This problem concerns many communication situations and involves different processes. Accordingly, the present work is organized in three research areas. The first part deals with the study of perceptions based on membership confined to a virtual environment. The second part focuses on the asymmetric modulation of gender perceptions on the Internet. The third part examines the influence of social norms and possibilities of expression in the CMC. Taken together, the results suggest that the CMC does not induce a weakening of social factors, but a modulation of the processes according to the characteristics of the context of interaction. The results are discussed in the light of the social identity theory, the self-categorization theory and the SIDE model.
256

Optimisation de la diffusion de l'énergie dans les smarts-grids / Energy distribution optimisation in Smart Grids

Guérard, Guillaume 27 November 2014 (has links)
Les systèmes technologiques actuels comprennent une composante sociétale due àl’impact des utilisateurs. Ces systèmes, dits complexes, comportent des sous-systèmesdont les acteurs ont des objectifs divergents voire antagoniques.Considéré comme une évolution du réseau énergétique actuel, le Smart Grid est unparfait exemple de système complexe. Ce terme désigne en particulier un réseau électriqueoptimisé intégrant le comportement et les actions des utilisateurs (producteurs,consommateurs, consommacteurs, etc.). L’étude de la dynamique du système a pourobjectif d’améliorer sa qualité et sa sécurité et de réduire son impact environnemental.Cependant, les simulations de Smart Grid actuelles sont généralement basées sur destechnologies spécifiques, limitant l’évolution du modèle proposé.Les défis liés au Smart Grid sont l’hétérogénéité des actions et de leurs intérêts divergeant,et une complexité à toute échelle, que ce soit spatiale ou temporelle. En effet, lesentités du Smart Grid sont en compétition pour l’obtention de la ressource commune.Par exemple, les consommateurs ont des besoins énergétiques à un cout minimal tandisque les producteurs doivent contrôler la consommation, les pics de demande tout enmaximisant leur profit. Les comportements et les relations entre les entités sont doncdifficiles à modéliser. Des pressions externes et internes comme la dynamique des prix oules productions erratiques des énergies renouvelables ont une influence sur la structure,l’organisation et le comportement des sous-systèmes et donc du système global. De plus,une mauvaise gestion peut provoquer de nombreuses défaillances du système telles quedes brownouts, des blackouts ou des ruptures de lignes du réseau.Nous proposons une modélisation intégrative pour aborder le concept de Smart Grid :chaque composante de notre modélisation prend en compte un aspect de ce dernier et leurintrication mène à une modélisation efficace à toute échelle. Les relations entre entitésprennent en compte le caractère dynamique et un superviseur global surveille le réseaupour détecter les seuils critiques ou pour planifier les schémas de consommation future.Cependant, le modèle est impossible à appréhender tel quel et de nombreux scénariostesteront l’influence des divers paramètres, calibreront les algorithmes et ajusteront lagestion locale et globale pour une configuration donnée. Nous proposerons de nouvellesthéories pour améliorer ce modèle au niveau de la structure, de la dynamique des prixou une approche mathématique dans le but de rendre le modèle le plus efficace possible / Current technological systems include a societal component due to the impact of users.These complex systems contain numerous sub-systems which actors have conflicting evenantagonist objectives.Considered as the evolution of the current Power Grid, the Smart Grid is a perfectexample of complex system. This term refers to an electrical optimized network integratingthe behavior and actions of users (generators, consumers, consumactors, etc.).These Power Grid’s upgrades aim to improve quality and security, to reduce environmentalimpact. But current simulations are done on a specific technology and with alimited evolution.Challenges of Smart Grid are related firstly to the heterogeneity of actors with differentinterests and secondly to a spatial and temporal multiscale complexity. Smart Gridactors are in a competitive access to a shared resource. For example, consumers expressenergy requirements with minimal cost while producers have to manage consumption,peaks and to maximize their profits. Dynamics behaviors and relations between entitiesare difficult to model. External and internal pressures as energy pricing, energy losses orthe erratic production of renewable energies influence on the structure, the organizationand the behavior of the subsystems and the overall system. Moreover, a bad managementcauses various structural problems like brownout, blackout, or partial failures.We propose an integrative model to solve the Smart Grid: each component of ourmodel allows to consider one aspect of the grid and it is their intricacy that achieves anefficient modeling. Relations between entities take into account the complex dynamicsand an overall supervisor allows network monitoring to detect critical thresholds or toplan consumption schemes. However, the model is impossible to apprehend like this anddifferent scenarios test the influence of parameters, calibrate algorithms and adjust globaland local monitoring for a specific case. We also propose some theories to enhance thestructural model, to integrate dynamic pricing or to help to calibrate by a mathematicalapproach of the global problem
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Subjektivní hodnocení nežádoucích účinků antiepileptik u pacientů s epilepsií / Subjective evaluation of adverse reactions of antiepileptic drugs in patients with epilepsy

Žalud, Jakub January 2019 (has links)
Jakub Žalud PhDr. Alena Javůrková Ph.D. adverse effects of antiepileptics, their classification and expression from the patient's subjective assumption was that the patient's experience of the adverse effects of antiepileptic drugs will significant overall (p˂0.05; R2 = 0.20). ts was not statistically significant (p˃0.05; R2 = 0.21). (p˃0.05; R2 = 0.16).
258

Client-side rendering och Server-side rendering : En komparativ studie ur ett prestanda-, SEO- och tillgänglighetsperspektiv / Client-side rendering and Server-side rendering : A comparative study from a performance, SEO and accessibility perspective

Weber, Mateusz January 2023 (has links)
Valet mellan client-side rendering och server-side rendering har varit en stor fråga de senasteåren. Server-side rendering har alltid varit den man lutar sig åt för snabba initialaladdningstider och SEO-optimering, men utvecklingen av webbsidor går snabbt och merinteraktiva webbsidor önskas av användare, där kommer client-side rendering in i valet och dåmåste man ta ett beslut. Denna komparativa studie genomfördes i syfte med att jämföra server-side rendering ochclient-side rendering. Jämförelsen gjordes på fyra testobjekt ur ett prestanda, SEO ochtillgänglighetsperspektiv. Prestandakriterierna som användes är first contentful paint, largestcontentful paint, speed index, total blocking time och cumulative layout shift. SEO-optimering mätte man igenom hur korrekt implementerad den var och samma förtillgängligheten. Fyra testobjekt valdes ut med liknande interaktivitet och funktionalitet för att få en sånoggrann jämförelse som möjligt. För att samla in data så användes verktyget Google Lighthouse som ett tillägg i webbläsaren Google Chrome. En sekvens följdes för att samla indata medan man interagerar med webbsidan för att se hur bra prestanda testobjekten har underinteraktivitet. Resultaten visade att båda renderingsteknikerna har både fördelar och nackdelar. Server-siderendering visade bättre prestandaresultat och SEO-optimering medan client-side hade bättreresultat på tillgänglighet och användbarhet. Sammanfattningsvis så rekommenderas en teknik beroende på vad för krav som ställs i början av projektet. Vill man ha en användarvänlig webbsida med mycket interaktivitet så rekommenderas client-side rendering och vill man ha en webbsida som har snabba laddningstider och bra SEO-optimering så rekommenderas server-side rendering.
259

A beiradeira e o grilador: ocupação no oeste do Pará / The \'beiradeira\' and the \'grilador\': ocupation and conflict in West Pará

Mauricio Gonsalves Torres 30 June 2008 (has links)
Como tantos outros extrativistas da Amazônia, a população de Montanha e Mangabal teve seu embrião no primeiro ciclo da borracha, em meados do século XIX, quando parte de seus ascendentes se instalou naquelas margens do Alto Tapajós. Desde então, eles resistiram à escravização por dívida na forma do aviamento; venceram as incertezas vindas com o fim dos tempos da seringa; encontraram soluções quando acabou o comércio das peles de gatos; sobreviveram à chegada e à derrocada dos garimpos, à malária, à contaminação por mercúrio e ao que mais foi preciso. Na década de 1970, muitos deles foram expulsos com requintes de truculência de parte de seu território com a criação do Parque Nacional da Amazônia. Mas a gente de Montanha e Mangabal persistiu também a isso e todos se reagruparam rio acima. Os anos 70 trouxeram ainda o acirramento da grilagem incentivada pelo garimpo e pelas obras da BR-163. Os beiradeiros concentraram-se na margem esquerda do rio Tapajós e, unidos, resistiram. Então apareceu a Indussolo, uma empresa paranaense autora da mais grandiosa e sofisticada fraude fundiária das tantas que a Amazônia é palco. Por meio de sentença judicial, obtiveram um Registro Torrens, uma espécie rara de título fundiário que, legitimado pelo Judiciário, torna a matrícula do imóvel incancelável e irretificável. Assim, a empresa engoliu a espantosa dimensão de 1.138.000 hectares e, dentro deles, quase todo o território de Montanha e Mangabal. Por anos eles vinham lutando contra a Indussolo, quando, em 2006, o Ministério Público Federal instaurou uma ação civil pública atacando a matrícula Torrens, a fim de tutelar a ocupação ancestral da população de Mangabal e Montanha. Esse trabalho nasceu desse momento, na intenção inicial de elaborar um levantamento fundiário que evidenciou o imenso ardil da empresa. Por outro lado, com base na viva fidelidade da tradição oral do grupo, pode-se retratar a outra face da ocupação daquelas terras: oito gerações daquelas pessoas, nascidas e enterradas, naquela terra / Like so many other Amazonian extractivists, the populations of Montanha and Mangabal trace their beginnings back to the first rubber cycle in the mid XIXth century when some of their ancestors installed themselves along the banks of the Upper Tapajos. Since then they have survived the debt bondage of the river trading system, the uncertain times that followed the end of the rubber epoch, the end of the trade in animal skins, the arrival and eventual collapse of the goldmining camps, malaria, mercury contamination and whatever else fate threw at them. In the 1970s many of them were expelled, often with violence, from part of their territory, by the creation of the Amazonia National Park. They resisted this too and regrouped further upriver. The 1970s also brought a worsening of landgrabbing practices, as a result of the goldmining and the building of the BR-163 highway. This led the inhabitants of Montanha and Mangabal to concentrate their dwellings on the left bank of the Tapajos and together, resist the pressures brought to bear on them. A Parana-based company called Indussolo then appeared on the scene. Armed with a court sentence, they obtained the Torrens register, an archaic and extremely rare form of land title, which legitimised their unchallengeable claim to the land . In this way they obtained an area of 1.138.000 hectares, which included almost all the land of the inhabitants of Montanha and Mangabeira. Again, these populations resisted expulsion, until in 2006 the federal prosecutors office brought a civic case against the legitimacy of the Torrens register, in defence of the ancestral rights of occupation of the existing populations. The elaboration of a land survey to demonstrate the scale of the fraud practised by the company was the origin of this thesis. The continuing practice of a lively oral tradition among the population enabled the accurate mapping of eight generations, born and buried in their lands
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A beiradeira e o grilador: ocupação no oeste do Pará / The \'beiradeira\' and the \'grilador\': ocupation and conflict in West Pará

Torres, Mauricio Gonsalves 30 June 2008 (has links)
Como tantos outros extrativistas da Amazônia, a população de Montanha e Mangabal teve seu embrião no primeiro ciclo da borracha, em meados do século XIX, quando parte de seus ascendentes se instalou naquelas margens do Alto Tapajós. Desde então, eles resistiram à escravização por dívida na forma do aviamento; venceram as incertezas vindas com o fim dos tempos da seringa; encontraram soluções quando acabou o comércio das peles de gatos; sobreviveram à chegada e à derrocada dos garimpos, à malária, à contaminação por mercúrio e ao que mais foi preciso. Na década de 1970, muitos deles foram expulsos com requintes de truculência de parte de seu território com a criação do Parque Nacional da Amazônia. Mas a gente de Montanha e Mangabal persistiu também a isso e todos se reagruparam rio acima. Os anos 70 trouxeram ainda o acirramento da grilagem incentivada pelo garimpo e pelas obras da BR-163. Os beiradeiros concentraram-se na margem esquerda do rio Tapajós e, unidos, resistiram. Então apareceu a Indussolo, uma empresa paranaense autora da mais grandiosa e sofisticada fraude fundiária das tantas que a Amazônia é palco. Por meio de sentença judicial, obtiveram um Registro Torrens, uma espécie rara de título fundiário que, legitimado pelo Judiciário, torna a matrícula do imóvel incancelável e irretificável. Assim, a empresa engoliu a espantosa dimensão de 1.138.000 hectares e, dentro deles, quase todo o território de Montanha e Mangabal. Por anos eles vinham lutando contra a Indussolo, quando, em 2006, o Ministério Público Federal instaurou uma ação civil pública atacando a matrícula Torrens, a fim de tutelar a ocupação ancestral da população de Mangabal e Montanha. Esse trabalho nasceu desse momento, na intenção inicial de elaborar um levantamento fundiário que evidenciou o imenso ardil da empresa. Por outro lado, com base na viva fidelidade da tradição oral do grupo, pode-se retratar a outra face da ocupação daquelas terras: oito gerações daquelas pessoas, nascidas e enterradas, naquela terra / Like so many other Amazonian extractivists, the populations of Montanha and Mangabal trace their beginnings back to the first rubber cycle in the mid XIXth century when some of their ancestors installed themselves along the banks of the Upper Tapajos. Since then they have survived the debt bondage of the river trading system, the uncertain times that followed the end of the rubber epoch, the end of the trade in animal skins, the arrival and eventual collapse of the goldmining camps, malaria, mercury contamination and whatever else fate threw at them. In the 1970s many of them were expelled, often with violence, from part of their territory, by the creation of the Amazonia National Park. They resisted this too and regrouped further upriver. The 1970s also brought a worsening of landgrabbing practices, as a result of the goldmining and the building of the BR-163 highway. This led the inhabitants of Montanha and Mangabal to concentrate their dwellings on the left bank of the Tapajos and together, resist the pressures brought to bear on them. A Parana-based company called Indussolo then appeared on the scene. Armed with a court sentence, they obtained the Torrens register, an archaic and extremely rare form of land title, which legitimised their unchallengeable claim to the land . In this way they obtained an area of 1.138.000 hectares, which included almost all the land of the inhabitants of Montanha and Mangabeira. Again, these populations resisted expulsion, until in 2006 the federal prosecutors office brought a civic case against the legitimacy of the Torrens register, in defence of the ancestral rights of occupation of the existing populations. The elaboration of a land survey to demonstrate the scale of the fraud practised by the company was the origin of this thesis. The continuing practice of a lively oral tradition among the population enabled the accurate mapping of eight generations, born and buried in their lands

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