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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Modèles probabilistes de l'évolution d'une population dans un environnement variable / Probabilistic modeles of a population evolving in a changing environment

Nassar, Elma 04 July 2016 (has links)
On étudie une équation différentielle stochastique animée par un processus ponctuel de Poisson, qui modélise un changement continu de lénvironnement d'une population et la fixation stochastique de mutations bénéfiques pour compenser ce changement. La probabilité de fixation d'une mutation augmente dès que le retard phénotypique $X_t$ entre la population et l'optimum augmente. On suppose que les mutations favorables se fixent instantanément induisant un saut adaptatif. En premier lieu, on a étudié le comportement à long terme de la solution de cette équation sachant qu'on ne considère qu'un seul trait phénotypique de la population et on a trouvé les conditions sous lesquelles $X_t$ est récurrent (possibilité de survie) ou transient (extinction inévitable). Ensuite, on a généralisé nos résultats en considérant un vecteur de traits phénotypiques de la population, essentiellement dans $mathbb R^2$. A la fin, on introduit une limite des petits sauts pour caractériser et comprendre le cas récurrent. / We study a stochastic differential equation driven by a Poisson point process, which models continuous changes in a population's environment, as well as the stochastic fixation of beneficial mutations that might compensate for this change. The fixation probability of a given mutation increases as the phenotypic lag $X_t$ between the population and the optimum grows larger, and successful mutations are assumed to fix instantaneously (leading to an adaptive jump). First, we study the large time behavior of the solution of this SDE taking into consideration one phenotypic trait of the population and we find the conditions under which $X_t$ is recurrent (possibility of survival) or transient (doomed to exctinction).Then we generalize our results to the case of a phenotypic traits vector, essentially in $R^2$. Finally, we introduce a small jumps limit to characterize and understand the recurrent case.
172

Classificação de soluções de algumas equações elípticas não lineraes

Barboza, Eudes Mendes 26 July 2013 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-03-22T11:11:05Z No. of bitstreams: 1 arquivototal.pdf: 1833639 bytes, checksum: aaa2e895cd2ba1edb07718225c7443ba (MD5) / Made available in DSpace on 2016-03-22T11:11:05Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1833639 bytes, checksum: aaa2e895cd2ba1edb07718225c7443ba (MD5) Previous issue date: 2013-07-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / In this work, we classify the solutions of the equation u + fue = 0 in R2 or R2 +. For this, we use basically the Moving Planes Method and and Moving Spheres Method. These methods ensure monotonicity and radial symmetry of the solution under certain conditions. The first method was used to study the case f 1 in R2 when RR2 eu is finite. The other was used to verify that the equation has no solution when f is a continuous function and radially symmetric, monotone in the region which has positive image and not constant. The latter method was also applied to the study of the problem ( u + eu = 0 em R2 +; @u @t = ceu=2 sobre @R2 +; for = 1; = 􀀀1 or = 0, modifying the conditions under the finiteness of RR2 + eu and R@R2 + eu=2. In most cases, when the equation has the solution, it was verified that the radially symmetrical. From this symmetry, we transform our Partial Differential Equations for Ordinary Differential Equations and we classify their solutions. / Neste trabalho, classificamos as soluções da equação u + feu = 0 em R2 ou R2 +. Para isso, utilizamos basicamente o Método dos Planos Móveis e o Método das Esferas Móveis, garantindo, sob certas condições a monotonicidade e a simetria radial da solução. O primeiro método foi usado para estudarmos o caso f 1, em R2 com RR2 eu finito. O outro foi utilizado para verificar que a equação não tem solução quando f é uma função contínua, radialmente simétrica e monótona na região em que tem imagem positiva e não constante. Este último método também foi aplicado no estudo do problema ( u + eu = 0 em R2 +; @u @t = ceu=2 sobre @R2 +; para = 1; = 􀀀1 ou = 0, modificando as condições em relação a finitude das integrais RR2 + eu e R@R2 + eu=2. Na maioria dos casos em que a equação tem solução, verificamos que esta era a radialmente simétrica. A partir dessa simetria, transformamos nas equações diferenciais parciais em equações diferenciais ordinárias e podemos classificar suas soluções.
173

Teoremas Tipo Liouville e Desigualdades Tipo Harnack para Equações Elípticas Semilineares via Método Moving Spheres

Lima, Jalman Alves de 10 June 2011 (has links)
Made available in DSpace on 2015-05-15T11:46:10Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 440995 bytes, checksum: d194a6a60d04b251160ec2e62f106e77 (MD5) Previous issue date: 2011-06-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, we will do some applications of the Moving Spheres method, a variant of the method of Moving Planes, in order to obtain some Liouville-type theorems and some Harnack-type inequalities in Rn, as well as in the Euclidian half space Rn +. Our study focuses on, mostly, in the article written by Yan Yan Li and Lei Zhan [32], as well as some references of the same article. We concentrate in studying some properties of positive solutions of some semilinear elliptic partial differential equations with critical exponent and giving different proofs, improvements, and extensions of some previously established Liouville-type theorems and Harnack-type inequalities. / Neste trabalho, faremos algumas aplicações do método Moving Spheres, uma variante do método Moving Planes, na obtenção de alguns teoremas tipo Liouville e de algumas desigualdades tipo Harnack em Rn, bem como no semi-espaço euclidiano Rn +. Nosso estudo se concentra, marjoritariamente, no artigo do Yan Yan Li e Lei Zhang [32], bem como algumas referências do mesmo. Nos concentramos em estudar propriedades de soluções positivas de algumas equações diferenciais parciais elípticas semilineares com expoente crítico e dar provas diversificadas, refinamentos e extensões de alguns Teoremas tipo Liouville e desigualdades tipo Harnack já estabelecidos.
174

Rozvoj pohybových schopností a dovedností v moderní gymnastice - srovnání závodnic SCM a běžného oddílu\\ / Development of moving skills and moving abilities in the Rhythmic gymnastic - controntation between competitresses from sport youth centre and common club.

KOPÁČOVÁ, Jana January 2007 (has links)
Theoretical part of this project mainly concerns the study of moving skills and abilities in the Rhytmic gymnastic. Basic devision of degree of difficulty and technic has been described. Moreover it briefly portrays a history of development of the Rhytmic gymnastics during the decades in the Czech Republic. Next part handle with comparism of the moving skills of contenders in the R.G. (In different clubs obviously approach to the training veried). Testing procedure had been running in clubs for 6 months. In this study there is also a wide photo attachment.
175

Catolicos e cinema na capital paulista : o cine clube do Centro Dom Vital e a Escola Superior de Cinema de São Luis (1958-1972) / Catholics and cinema in the São Paulo capital : the cine clube of "Centro Dom Vital" and the "Escola Superior de Cinema" of São Luis (1958-1972)

Malusa, Vivian 13 August 2018 (has links)
Orientador: Nuno Cesar Pereira de Abreu / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Artes / Made available in DSpace on 2018-08-13T04:25:01Z (GMT). No. of bitstreams: 1 Malusa_Vivian_M.pdf: 9653988 bytes, checksum: 524af66a8fdbfd7851fb574832a5359e (MD5) Previous issue date: 2007 / Resumo: Esta pesquisa teve como finalidade compreender a atuação católica no campo cinematográfico na capital paulista, com relação, especialmente, às atividades do Cineclube do Centro Dom Vital e a Escola Superior de Cinema São Luis. O recorte temporal escolhido, entre 1958 e 1972, refere-se, respectivamente, à criação do Cine-clube do Centro Dom Vital e ao final das atividades da Escola Superior de Cinema. Objetivou-se analisar as relações entre a atuação nestas duas instituições católicas - a primeira relacionada à formação cultural cinematográfica e a segunda, à tentativa de implantação de uma formação prática - às concepções católicas com relação ao cinema na época, presentes em textos pontificais, de organizações internacionais católica de cinema, em especial o OCIC (Office Catholique International du Cinéma), ou ainda de militantes católicos brasileiros que trabalharam em prol do apostolado cinematográfico - leigos ou do clero. Além disso, relacionaram-se as atividades promovidas pelas duas instituições à formação de futuros críticos, teóricos de cinema e cineastas sem qualquer relação com a ideologia cristã. Desta forma, compreendeu-se ainda como se dava a relação entre militância católica e críticos desvinculados desta ideologia, e instituições católicas e laicas em função de uma melhor compreensão do fenômeno cinematográfico e de uma consolidação da cultura cinematográfica em São Paulo, e no Brasil. Como metodologia, utilizou-se em grande parte fontes primárias, além da bibliografia secundária e de textos de embasamento teórico com relação à escrita histórica a partir destas fontes. Os resultados do trabalho demonstraram que apesar de terem sido criadas a partir de intenções católicas claramente baseadas nas diretrizes de então, inclusive no que se refere à metodologia de trabalho, nas atividades do Cine-clube do Centro Dom Vital e da Escola São Luis, o campo cinematográfico sobressaiu-se aos ideais do campo religioso. / Abstract: This research aimed to comprehend the work of the Catholic church within the cinematographic field in São Paulo, regarding specifically the activities of Centro Dom Vital and Escola Superior de Cinema São Luis. The period chosen, between 1958 and 1972, refers to the creation of Cine-clube do Centro Dom Vital and the closure of Escola Superior de Cinema. Its purpose was to analize the relations between these catholic institutions-the first related to the consolidation of a cinematographical culture and, the second, to the attempt of implementing a practical education-and the catholic conceptions regarding the film culture of the period, present in texts written by popes, by international catholic cinema organizations, specially the OCIC (Office Catholique International du Cinéma), or by the Brazilian Catholics militants working for the cinema apostolate - of the laicity or clergy. It also linked the activities of these instituitions to the appearance of future film critics, film theoreticians and film makers wihtout any connection with the christian ideology. This way, it also understood how the relation between the Catholic militancy and critics unnatached of such ideology took place, so between Laic and Catholic Institutions, in order to understand the cinematographic phenomena and its consolidation in São Paulo and in Brazil. This research used in its methodology a great part of primary sources, a secundary bibliography and theoretical texts regarding the historical writtings based on such sources. The results demonstrated that even though these institutions were created with catholic intentions based on the lines of directions of the period, including the methology work, in the activities of Cine-clube Centro Dom Vital and Escola São Luis the cinematographic experience surpassed the ideals of religion. / Mestrado / Mestre em Multimeios
176

Folhear memorias : das imagens literarias as imagens cinematografias / Leaf through memories : from literary images to cinematographic images

Seki, Celia Harumi 23 August 2007 (has links)
Orientador: Antonio Fernando da Conceição Passos / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Artes / Made available in DSpace on 2018-08-11T06:00:45Z (GMT). No. of bitstreams: 1 Seki_CeliaHarumi_D.pdf: 2731695 bytes, checksum: 61a864c82617352109523856e33f8e7a (MD5) Previous issue date: 2007 / Resumo: Esta pesquisa apresenta como tema principal o processo de criações artísticas audiovisuais inspiradas em textos literários. Da leitura dos textos poéticos decorrem imagens e sensações de caráter singular, que são transpostas para obras audiovisuais. A pesquisa realizada na área de Cinema e Literatura, dentro da linha de pesquisa ¿CINEMA FICCIONAL: HISTÓRIA E PROCESSOS CRIATIVOS¿, tem como objetivo expor o desenvolvimento do fazer criativo da autora, através de sua história pessoal, memórias, sentimentos, sensações estéticas concretizadas nas realizações de filmes e vídeos sob o tema geral do Exílio / Abstract: This research has in its main subject the process of audiovisual artistic creations inspired in literary texts. From the lecture of poetic texts results images and sensations of a singular nature, that are transported to audiovisual works. The research has been realized in ¿Movies and Literature¿ area, and focused in the research line ¿FICTIONAL MOVIES: HISTORY AND CREATIVE PROCESSES¿, with the purpose to expose the author¿s creative work development through her personal history, memories, feelings, aesthetics sensations realized in the creations of films and videos in the light of Exile general subject / Doutorado / Doutor em Multimeios
177

Determinação de distâncias cinemáticas de estrelas pré-sequência principal em regiões de formação estelar / Determination of Kinematic Distances of Pre-Main Sequence Stars in Star-Forming Regions

Phillip Andreas Brenner Galli 18 December 2012 (has links)
Este trabalho tem como objetivo principal a determinação da distância de estrelas pré-sequência principal em regiões de formação estelar próximas. A determinação precisa da distância individual das estrelas é necessária para obter os principais parâmetros físicos de cada estrela e para investigar a estrutura da Galáxia. Em particular, investigamos as regiões de formação estelar de Lupus e Ophiuchus que contém uma das associações mais ricas em estrelas T Tauri. A grande maioria das estrelas pré-sequência principal nessas regiões não foi observada pelo satélite Hipparcos devido à sua magnitude e também não têm paralaxe trigonométrica medida a partir do solo devido à distância em que se encontram. O procedimento aqui empregado para a obter a distância individual das estrelas baseia-se na estratégia de ponto de convergência e utiliza dados de movimento próprio e velocidade radial. Desenvolvemos uma nova versão do método de ponto de convergência que permite simultaneamente determinar a posição do ponto de convergência e selecionar os membros de um moving group. Partindo dos dados de movimento próprio e o novo método aqui desenvolvido investigamos as propriedades cinemáticas e realizamos uma análise de pertinência das estrelas em cada região estudada o que nos permitiu identificar um moving group com 114 estrelas em Lupus e 55 estrelas em Ophiuchus. Calculamos a distância para cada membro do grupo usando velocidades radiais publicadas, que foram complementadas com novas observações, e a velocidade espacial do moving grup para as estrelas com velocidade radial não conhecida. Calculamos as paralaxes com precisão de 1-2~mas o que implica em um erro relativo médio de 25% nas distâncias obtidas. Finalmente, investigamos as propriedades dos diversos subgrupos e a estrutura tridimensional dos complexos de nuvens em Lupus e Ophiuchus, concluindo que existem efeitos de profundidade importantes. Utilizamos os novos resultados de distância para obter os parâmetros físicos (luminosidade, massa e idade) das estrelas e o diagrama-HR de cada região de formação estelar considerada, confirmando a distribuição de idade diferente das duas subclasses de estrelas T Tauri. Os resultados aqui obtidos representam um primeiro passo no sentido de melhor entender a estrutura das regiões de formação estelar e os estágios iniciais da formação de estrelas e planetas. / The main objective of this work is to determine the distance of pre-main sequence stars in nearby star-forming regions. A precise determination of the distance to individual stars is required to accurately determine the main physical parameters of each star and the structure of the Galaxy. Here we investigate the Lupus and Ophiuchus star-forming regions that contain one of the richest associations of T Tauri stars. Most pre-main sequence stars in these regions were neither observed by the Hipparcos satellite due to their magnitude nor have any trigonometric parallax measured from the ground due to their distance. The procedure that we use here to derive the distance to individual stars is based on the convergent point strategy and makes full use of proper motion and radial velocity data. We developed a new version of the convergent point search method that simultaneously determines the convergent point position and selects the most likely members of a moving group. Based on proper motion data and our new method we investigate the kinematic properties and perform a membership analysis of the stars in each star-forming region considered that allows us to identify a moving group with 114 stars in Lupus and 55 stars in Ophiuchus. We calculate the distance of each group member using published radial velocities, which we supplemented with new measurements, and the spatial velocity of the moving group for the remaining stars with unknown radial velocity. We derived parallaxes with accuracies of 1-2 mas yielding the average relative error of 25% on the distances. Finally, we investigate the properties of the various subgroups and the three dimensional structure of the Lupus and Ophiuchus cloud complex and conclude that significant depth effects exist. We use the new distances to refine the physical parameters (luminosity, mass and age) of stars and the HR-diagram for each star-forming region considered confirming the different age distribution of the two T Tauri subclasses. These results represent a first step towards better understanding the structure of star-forming regions and the early stages of star and planet formation.
178

Robustní detekce pohybujících se objektů ve videu / Robust Detection of Moving Objects in Video

Klicnar, Lukáš January 2012 (has links)
Motion segmentation is an important process for separating moving objects from the background. Common methods usually assume fixed camera, other approaches exist as well, but they are usually very computational intensive. This work presents an approach for scene segmentation to regions with coherent motion, which works faster than similar methods and it is capable of online processing with no prior knowledge of objects or camera. The main assumption is that the points belonging to a single objects are moving together and this applies as well in the opposite direction. The proposed method is based on tracking of feature points and searching for groups with similar motion by using RANSAC-based algorithm. Short-range repair of broken tracks is applied to increase the overall robustness of tracking. Found clusters are subsequently processed to represent separate moving objects.
179

Implementation of Anomaly Detection on a Time-series Temperature Data set

Novacic, Jelena, Tokhi, Kablai January 2019 (has links)
Aldrig har det varit lika aktuellt med hållbar teknologi som idag. Behovet av bättre miljöpåverkan inom alla områden har snabbt ökat och energikonsumtionen är ett av dem. En enkel lösning för automatisk kontroll av energikonsumtionen i smarta hem är genom mjukvara. Med dagens IoT teknologi och maskinlärningsmodeller utvecklas den mjukvarubaserade hållbara livsstilen allt mer. För att kontrollera ett hushålls energikonsumption måste plötsligt avvikande beteenden detekteras och regleras för att undvika onödig konsumption. Detta examensarbete använder en tidsserie av temperaturdata för att implementera detektering av anomalier. Fyra modeller implementerades och testades; en linjär regressionsmodell, Pandas EWM funktion, en EWMA modell och en PEWMA modell. Varje modell testades genom att använda dataset från nio olika lägenheter, från samma tidsperiod. Därefter bedömdes varje modell med avseende på Precision, Recall och F-measure, men även en ytterligare bedömning gjordes för linjär regression med R^2-score. Resultaten visar att baserat på noggrannheten hos varje modell överträffade PEWMA de övriga modellerna. EWMA modeller var något bättre än den linjära regressionsmodellen, följt av Pandas egna EWM modell. / Today's society has become more aware of its surroundings and the focus has shifted towards green technology. The need for better environmental impact in all areas is rapidly growing and energy consumption is one of them. A simple solution for automatically controlling the energy consumption of smart homes is through software. With today's IoT technology and machine learning models the movement towards software based ecoliving is growing. In order to control the energy consumption of a household, sudden abnormal behavior must be detected and adjusted to avoid unnecessary consumption. This thesis uses a time-series data set of temperature data for implementation of anomaly detection. Four models were implemented and tested; a Linear Regression model, Pandas EWM function, an exponentially weighted moving average (EWMA) model and finally a probabilistic exponentially weighted moving average (PEWMA) model. Each model was tested using data sets from nine different apartments, from the same time period. Then an evaluation of each model was conducted in terms of Precision, Recall and F-measure, as well as an additional evaluation for Linear Regression, using R^2 score. The results of this thesis show that in terms of accuracy, PEWMA outperformed the other models. The EWMA model was slightly better than the Linear Regression model, followed by the Pandas EWM model.
180

Reasoning about Moving Target Defense in Attack Modeling Formalisms / Resonemang om Rörligt Målförsvar i Attackmodelleringsformalismer

Ballot, Gabriel January 2022 (has links)
Since 2009, Moving Target Defense (MTD) has become a new paradigm of defensive mechanism that frequently changes the state of the target system to confuse the attacker. This frequent change is costly and leads to a trade-off between misleading the attacker and disrupting the quality of service. Optimizing the MTD activation frequency is necessary to develop this defense mechanism when facing realistic, multi-step attack scenarios. Attack modeling formalisms based on DAG are prominently used to specify these scenarios. It represents the attack goal in the root of a tree that is recursively refined into subgoals to show the different ways the attacker can compromise the system. According to some specific models, the tree is augmented with countermeasures, time, costs, or probabilities. Our contribution is a new DAG-based formalism for MTDs and its translation into a Price Timed Markov Decision Process to find the best activation frequencies against the attacker’s time/cost-optimal strategies. For the first time, MTD activation frequencies are analyzed in a state-of-the-art DAG-based representation. Moreover, this is the first paper that considers the specificity of MTDs in the automatic analysis of attack modeling formalisms. Finally, we present some experimental results using UPPAAL STRATEGO to demonstrate its applicability and relevance. / Sedan 2009 har Moving Target Defense (MTD) blivit ett nytt paradigm av defensiv mekanism som ofta ändrar målsystemets tillstånd för att förvirra angriparen. Denna frekventa förändring är kostsam och leder till en avvägning mellan att vilseleda angriparen och att störa målsystemets tillförlitlighet. Att optimera MTD-aktiveringsfrekvensen är nödvändigt för att utveckla denna försvarsmekanism när man står inför realistiska attackscenarier i flera steg. Attackmodelleringsformalismer baserade på DAG är de främst använda metoderna för att specificera dessa scenarier. Metoden representer attackmålet i roten av ett träd som rekursivt förfinas till delmål för att visa de olika sätt som angriparen kan äventyra systemet. Enligt vissa specifika modeller är trädet utökat med motåtgärder, tid, kostnader eller sannolikheter. Vårt bidrag är en ny DAG-baserad formalism för MTD:er och dess översättning till en Price Timed Markov Decision Process för att hitta de bästa aktiveringsfrekvenserna mot angriparens tids-/kostnadsoptimala strategier. För första gången analyseras MTD-aktiveringsfrekvenser i en toppmodern DAG-baserad representation. Dessutom är detta det första rapporten som överväger specificiteten hos MTD:er i den automatiska analysen av attackmodelleringsformalismer. Slutligen presenterar vi några experimentella resultat med UPPAAL STRATEGO för att visa dess tillämpbarhet och relevans.

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