This master thesis is a programmer's guide book of a concurrent programming on the Java 8 platform. Concurrency brings additional issues that cannot occur in single-threaded ap-plications. One of the thesis' objectives is to analyze these issues and introduce several principles that, in case they are properly followed, help to create flawless and well-behaving concurrent applications. Another goal of this thesis is to describe the Java con-currency programming from the theoretical point of view. Firstly, the thesis is focused on basic thread development and synchronization issues. Later, it introduces the features and instruments that are provided by Java 5 and higher versions. The theoretical passages are enriched by practical examples that perform discussed features and help to clarify some specific issues. The thesis is written in Czech language and covers large set of concurrency topics from the very basics through the utility libraries to modern instruments present in Java 8.

L’objectif principal de cette thèse vise la compréhension et la maitrise des mécanismes physiques menant à l’excitation du mode gyrotropique de vortex magnétique par transfert de spin, et en particulier l’origine des sources de bruit affectant sa dynamique. Ce travail est effectué dans la perspective de parvenir à l’amélioration des propriétés radiofréquences de ces dispositifs appelés Spin Transfer Oscillator.En effet, ces oscillateurs ont l’avantage d’être de taille submicronique (quelques dizaines à quelques centaines de nm), d’être compatibles avec les technologies CMOS et d’être résistants aux radiations. De plus, les mécanismes d’aimantation mis en jeu leur assurent une forte dépendance de la fréquence avec le courant, i.e. une bonne accordabilité, ainsi qu’une réponse dynamique rapide i.e. une agilité élevée. Cependant, différentes questions restent en suspens quant à la possibilité d’améliorer leurs conditions d’oscillations, leur puissance et la cohérence de leurs oscillations.Un premier aspect de mon travail de thèse a été d’étudier l’influence des fluctuations thermiques sur la dynamique entretenue du mode gyrotropique du cœur de vortex. Un des résultats a été de montrer que le bruit de phase du mode gyrotropique résulte majoritairement de fluctuations de phase issues directement des fluctuations thermiques auxquelles s’ajoutent des fluctuations d’amplitude converties en fluctuations de phase. Grâce à un modèle analytique, nous avons pu mettre en évidence le rôle important joué par les non-linéarités des forces agissant sur le vortex. De plus, nous avons pu mesurer les paramètres caractéristiques de l’oscillateur, à savoir, la rapidité à changer sa fréquence mais aussi le facteur de couplage amplitude-phase.La seconde étape de mes travaux a consisté à améliorer les conditions d’obtention de signal rf. Un résultat majeur de ce travail a été l’obtention d’un signal rf puissant en absence de champ magnétique. Les puissances mesurées sont de quelques centaines de µW correspondant à des largeurs de raie faibles allant de quelques centaines de kHz à quelques MHz. Cette spécificité est rendue possible pour une structure complexe de l’oscillateur où la couche magnétique qui polarise en spin le courant a une aimantation perpendiculaire et est différente de la couche de référence pour la magnétorésistance.La troisième étape a été d’optimiser le rendement de l’oscillateur. Un des résultats marquants est que nous avons pu mesurer une puissance rf émise record s’élevant à 3.6 µW, encore jamais obtenue à température ambiante pour les oscillateurs à transfert de spin à base de vortex. Ces fortes puissances résultent du développement de nouvelles jonctions à base de FeB effectués par le groupe de S. Yuasa (AIST, Japon) pour lesquelles l’amélioration de la qualité de la jonction, nous a permis d’obtenir une magnétorésistance atteignant 125% .La faible taille de l’oscillateur a donc un coût qui se paye en termes de bruit de phase. Une solution qui permettrait de résoudre cette limitation et d’améliorer la cohérence des oscillations est la synchronisation mutuelle de plusieurs oscillateurs à transfert de spin au travers des courants rf émis par chacun. Ainsi, la dernière étape de ma thèse a été d’étudier le comportement du mode gyrotropique lorsqu’il est soumis à un courant alternatif. Un résultat important a été de montrer, grâce à une étude expérimentale appuyée sur un modèle analytique, le rôle crucial des non-linéarités et des symétries des forces de synchronisation du mode excité.Ces différents travaux nous ont fournis les outils pour mieux comprendre la dynamique du vortex magnétique et nous ont amené à mettre en place un banc de mesure original pour lequel l’oscillateur se synchronise sur lui-même. En fonction du retard avec lequel le signal émis par l’oscillateur est réinjecté, nous avons pu montrer pour la première fois que la fréquence, la puissance mais aussi la largeur de raie des oscillations peuvent être modulées. / The main goal of this thesis is the understanding of the physical mechanisms and the subsequent control of the properties at the origin of the spin transfer induced magnetic vortex gyrotropic motion in confined systems. In particular the origin of the noise affecting the dynamics has been investigated. This work has been performed with a view to improving the radiofrequency (rf) properties of the so-called Spin Transfer Oscillator (STO).The advantages of such oscillators are their sub-micron size (from few tens to hundreds of nanometres), their compatibility with CMOS technologies and their radiation hardness. Moreover, the magnetization dynamics involved permit a large tunability of frequency as a function of the applied current and a high agility i.e. a fast dynamical response. Nevertheless, several open questions exist regarding the possible optimization of the sustained oscillation conditions and the improvement of the STO power and spectral coherence.The first aspect of my work was to investigate the influence of thermal fluctuations over the sustained vortex core gyrotropic motion. One of the key results of my thesis was to show that the phase noise results from direct phase fluctuations from thermal fluctuations plus amplitude fluctuations converted to phase noise. With an analytical model, we were able to highlight the major role played by the non-linearities of the forces acting on the vortex core. In addition, we were able to measure the characteristic parameters of the oscillator, namely, the speed of frequency response to perturbations as well as the phase-amplitude coupling coefficient.The second important part of my work has been to improve the conditions for obtaining an rf signal. An important result of this work was the measurement of a powerful rf signal in the absence of a magnetic field. The measured powers are a few hundred milliwatts and correspond to low linewidths, ranging from a few hundred kilohertz to a few megahertz. The zero field behaviour was made possible due to the complex structure of the oscillator where the magnetic layer which polarizes the spin current has a perpendicular magnetization, in contrast to the in-plane polarized reference layer.The third step was to optimize the performance of the oscillator. One of the striking results of this thesis is that we measured a record rf output power, up to 3.6 µW, the largest obtained at room temperature for vortex based STOs so far. This high output power results from the development of new FeB based junctions made by the group of Pr. S. Yuasa (AIST, Japan), where the improvement of the quality of the junction allowed us to obtain a magnetoresistance up to 125%.The small size of the oscillator has a cost that is paid in terms of the phase noise. One possible solution that would solve this limitation and enhance the coherence of the oscillations is via mutual synchronization of several STOs through rf currents emitted by each oscillator. Thus, the last stage of my thesis was to study the behaviour of gyrotropic motion when subjected to an alternating current. An important result was to show, through an experimental study in conjunction with an analytical model, the crucial role of the non-linearities and symmetries of the synchronization forces.These various studies have provided us the tools to better understand the dynamics of magnetic vortex and led us to develop an original tester for which the oscillator synchronizes itself with its own rf signal. Depending on the delay at which the oscillator is fed back, we showed for the first time that the frequency, the power and also the linewidth of the oscillations can be modulated.

This thesis is an analysis of frameworks which support multithreading application devel-opment on platform Java. In particular this thesis analyses the overview of libraries which supports multithreading development in this language. Provided features are shown and described by the code examples. The thesis describes the principles of concurrent pro-gramming. Although multithreaded applications undoubtedly have many advantages, one of the goals of the thesis is to highlight the possible risks associated with their use. By the analysis of Java platform, I used method of description, analysis, synthesis and comparison. This thesis is composed of theoretical part, which defines the basic concepts and principles of concurrent applications. Theoretical parts also contain recherché of works, which deal with the topic of concurrent programming. In the analytical part are described and evaluated changes at various versions of Java language. Benefit of this work is clear documentation and evaluation of Java language concurrent utilities, from the oldest version of Java 1 to latest Java 8. So this work can help those, who need to learn how to develop concurrent applications in Java.

Orientador: Robson Pederiva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-26T21:11:27Z (GMT). No. of bitstreams: 1 Chagas_ClodoaldoBorges_M.pdf: 26402874 bytes, checksum: d4bfb8b718bb540f2313823b84724082 (MD5) Previous issue date: 2015 / Resumo: Os sistemas de transmissão por correntes são umas das principais formas de se transmitir torque e potência entre eixos paralelos. A confiabilidade dos sistemas de transmissão por corrente na sincronização do eixo de manivelas e do eixo de comando de válvulas nas aplicações automotivas tem permitido seu emprego durante toda a vida útil do motor. A aparente vantagem no uso dos sistemas de corrente esconde algumas características indesejáveis inerentes a esse tipo de transmissão. Alguns fenômenos físicos como a "Ação Poligonal" a qual faz com que ocorra flutuação da razão entre as velocidades angulares do eixo movido e motriz, mesmo quando o eixo motriz está em velocidade angular constante, puderam ser modelados por meio da analise cinemática e validados experimentalmente em situações "quasi-estáticas". As guias de corrente são inicialmente elementos cuja principal função é atenuar as vibrações transversais da corrente. No entanto, o estudo desenvolvido constatou a guia como sendo um importante mecanismo cuja posição e geometria podem minimizar a flutuação da razão entre as velocidades angulares. Outro importante aspecto aponta a necessidade da existência de elementos com a capacidade de permitir um auto ajuste de posicionamento durante o ciclo de engate de um elo de corrente. Compreender o carregamento aplicado pela corrente sobre a guia tensora torna possível predizer o estado de tensão deste componente bem como o coeficiente de atrito entre corrente e guia. A interação dos resultados teóricos e experimentais puderam ser introduzidos em um software comercial de elementos finitos para determinação do estado de tensão da guia. Os resultados da extensometria aplicada na guia de corrente foi confrontada aos resultados deste software a fim de obter a validação dos modelos desenvolvidos no presente trabalho. O estudo dos modelos matemáticos em paralelo aos experimentos guiam o desenvolvimento do presente trabalho / Abstract: The chain transmission systems are among the most important ways to transfer power and torque between parallel axes. The reliability of the chain transmission systems for synchronizing the crank shaft and command shaft in the automotive engines allows that this type of transmission system can be employed during the whole life of the passenger car engine. This apparent advantage in the use of the chains hides some undesirable characteristics which are inherent to this kind of discrete system. Some physical phenomena such as cinematic analysis of the "Polygonal Action" which makes the ration between angular velocity of driven and driving axis fluctuate during a chain link engagement, even when the velocity of the driving shaft is at constant angular velocity. This fluctuation was modeled and experimental tests were carried out to validate the model for "quasi-static" situations. The chain guide and chain blades are initially elements which the main function is to hold the transversal vibration of the chain. The present study identified the chain guide profile and assembly position as an important helping component to minimize the fluctuation of angular velocity ratio between sprockets. Another important feature of the transmission system picks up the necessity of at least one of the system components has to be able to self-adjust during the engagement cycle. The comprehension of the contact forces which loads the chain blade by the chain becomes possible understanding the stress state of this component and determine the friction coefficient between chain and blade. The interaction of theoretical and experimental results were introduced as incomes at commercial finite element software to determine the stress state of this component. The measurements of the extensometers were compared to the commercial software to validate the mathematical models and simplification adopted in the present work. The mathematical model in parallel to the experimental procedures drive the development of the present work / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica

Cadeias de suprimentos podem ter operações seguindo diferentes estratégias de distribuição e a utilização de cada uma dessas estratégias pode resultar em diferentes operações e custos. A estratégia de cross-docking auxilia na redução dos custos de distribuição de produtos, consolidando cargas, e a redução de tempo e custos de armazenamento, uma vez que o tempo máximo de estoque permitido pela estratégia é de cerca de 24 horas. O objetivo deste trabalho é apresentar um modelo para o problema de cross-docking, em que cargas são entregues e reorganizadas de forma a atender a outras cargas que são coletadas e garantir que as janelas de tempo para início das operações sejam atendidas. Devido à falta de instâncias para o problema disponíveis na literatura, buscou-se gerar um benchmark e disponibilizá-las à comunidade científica. Uma vez que o problema é de difícil solução exata, um método heurístico para a resolução do problema foi desenvolvido. Os resultados mostraram que o modelo proposto resulta em boas soluções quando comparado ao modelo da literatura. O estudo de calibração do software IBM CPLEX mostrou que a calibração dos parâmetros pode resultar em melhores soluções e, por fim, a matheurística se mostrou competitiva com o CPLEX, principalmente para cenários em que a proporção de entregas e coletas diverge. / Supply chains may have operations which follow different distribution strategies and each one of these strategies may result in different operations and costs. The Cross-docking strategy helps to reduce the products distribution costs by consolidating loads and reducing storage costs as the maximum inventory time is approximately 24 hours. The aim of this research is to present a model for the cross-docking problem where loads are delivered and reorganized so as to cater for other loads that are collected and ensure that time windows are respected. Due to the lack of instances available in the literature, a benchmark was generated and was made available to the scientific community. As the problem is difficult to obtain the exact solution, a heuristic method was developed. The results showed that the proposed model has good solutions when compared to the literature model. A study of the IBM CPLEX software showed that tuning can result in better solutions and the matheuristcs was competitive with the software, mainly in scenarios where deliveries and pickups are very different.

Made available in DSpace on 2016-05-02T13:55:50Z (GMT). No. of bitstreams: 1 Priscila Cristina Martins MagalhaesDissertacao.pdf: 1478926 bytes, checksum: 6f3da0417b4c9aa46e9fc1ca9cbda08b (MD5) Previous issue date: 2013-12-20 / In search of economically viable biotechniques to improve reproductive efficiency in cattle breeding, this study aimed to evaluate the technical viability of the use of synchronization protocols after the first fixed-time artificial insemination (FTAI) and before the pregnancy diagnosis. In the first experiment, the FTAI followed by estrous detection was compared to conventional AI and to FTAI followed by resynchronization 21 days after FTAI; and to conventional IA. The same protocol was used for te groups that utilized FTAI, with the following chronology: day 0, insertion of progesterone intravaginal device and treatment with 2 mg of estradiol benzoate; day 8, removal of the device and injection of 500 mg of sodium cloprostenol and 1 mg of estradiol cypionate; day 10, FTAI. Twenty one days after FTAI, every cow in the resynchronization group received a intravaginal implant of 1 mg of estradiol benzoate. After pregnancy diagnosis, on day 28, the empty animals received 500 mg of sodium cloprostenol, 1 mg of estradiol cypionate and the implant was removed. FTAI was done on day 30. Conventional AI was performed 12 hours after estrous detection with the use of a teaser. It was observed that the conception rate did not differ with the treatments after the first service, neither did the pregnancy rate at the end of 90 days of breeding period. In the second experiment, the resynchronization protocol was compared to FTAI followed by natural mating in zebu cows, used in the production of F1 Holstein x Zebu females. The effect of the resynchronization on the pregnancy rate over 75 days of BP was not observed. The resynchronization was inefficient to induce cyclicity in cows in anoestrus after the first FTAI. The resynchronization, before the pregnancy diagnosis, must be used carefully, specially in situations where the estrous detection is low. / Na busca de biotécnicas economicamente viáveis para a melhoria da eficiência reprodutiva na pecuária, objetivou-se, com este trabalho, avaliar a viabilidade técnica da utilização de protocolos de ressincronização após a primeira inseminação artificial em tempo fixo (IATF) e antes do diagnóstico de gestação. No primeiro experimento, comparou-se a IATF seguida de observação de cio e à IA convencional e à IATF seguida de ressincronização 21 dias após a IATF; à IA convencional. Foi utilizado um mesmo protocolo para os grupos que utilizaram a IATF, seguindo a seguinte cronologia: dia 0, inserção de dispositivo intravaginal de progesterona e aplicação de 2 mg de benzoato de estradiol; dia 8, retirada do dispositivo e aplicação de 500 mg de cloprostenol sódico e 1 mg de cipionato de estradiol; dia 10, IATF. Aos 21 dias pós-IATF, todas as vacas do grupo ressincronização receberam um implante intravaginal e 1mg de benzoato de estradiol. Após o diagnóstico de gestação, no dia 28, os animais vazios receberam 500mg de cloprostenol sódico, 1 mg de cipionato de estradiol e o implante foi removido. A IATF foi procedida no dia 30. A IA convencional foi realizada 12 horas após observação de cio, com auxílio de rufião. Observou-se que não houve efeito de tratamento na taxa de concepção, após o primeiro serviço, nem na taxa de prenhez ao final de 90 dias de EM. No segundo experimento, comparou-se o protocolo de ressincronização à IATF seguida de monta natural em vacas zebuínas, utilizadas na produção de fêmeas F1 Holandês x Zebu. Também não foi observado efeito da ressincronização sobre a taxa de prenhez acumulada em 75 dias de EM. A ressincronização foi ineficiente para induzir a ciclicidade nas vacas em anestro após a primeira IATF. A ressincronização, antes do diagnóstico de gestação, deve ser adotada de forma criteriosa, principalmente, em situações em que a eficiência na detecção de cio seja baixa.

Na década de 60, começaram a ser utilizadas técnicas e sincronização do estro, e durante os últimos trinta anos tem sido despertado o interesse do desenvolvimento de métodos para sincronizar o estro de ovelhas. Na maioria das vezes a IA está associada à um protocolo de sincronização do estro podendo assim ser realizada a Inseminação Artificial em Tempo Fixo (IATF). Três experimentos foram realizados com objetivo de avaliar a influência do efeito macho e tipos de rufião, reutilização do dispositivo e o método de inseminação utilizado, na sincronização do estro através do uso de dispositivos intra-vaginais (CIDR®- Control Internal Drog Release), associado com a aplicação intramuscular de eCG e PGF2 , sobre a taxa detecção e tempo médio para aparecimento do estro, taxa de prenhez na IATF e no primeiro estro após a sincronização. Exp. I: Foram utilizadas 270 ovelhas, separadas em três tratamentos: SM = (controle) sem rufiões; DL= recebeu rufiões com Desvio lateral peniano e o VS= recebeu rufiões vasectomizados. Os tratamentos foram submetidos ao mesmo protocolo, CIDR® por 7d, aplicação de 300UI de eCG e 6,71 mg de Dinoprost trometamina, na retirada do CIDR. As ovelhas foram submetidas a IATF pelo método transcervical em 55h após a retirada do CIDR. EXP.II: Foram utilizadas 275 ovelhas, divididas em 4 tratamentos: 7N= 7d com CIDR novo; 7U= 7d com CIDR já usado por 7d; 11N= 11d com CIDR novo; 11U= 11d com CIDR já usado por 7d. No dia da retirada do CIDR (D7 ou D11) foi realizada a aplicação de 300 UI de eCG e 6,71 mg de Dinoprost trometamina. As ovelhas foram submetidas a IATF pelo método transcervical, 49h após a retirada do CIDR. Exp.III: Foram utilizadas 247 ovelhas, divididas em 4 tratamentos: MN= as ovelhas foram sincronizadas e submetidas a monta natural com carneiros; IATF = as ovelhas foram submetidas a IATF por laparoscopia 48h após a retirada do CIDR; IATF+GnRH= as ovelhas foram submetidas a IATF por laparoscopia + 0,05 mg de Gonadorelina, quando 50% das ovelhas apresentaram sinais de estro; IA= as ovelhas foram inseminadas por laparoscopia no sistema AM/PM, 12h após o início dos sinais de estro. Todos os tratamentos foram submetidos ao mesmo protocolo, CIDR por 11 dias, aplicação de 300UI de eCG e 6,31 mg de Dinoprost trometamina, na retirada do CIDR. Nos experimentos I e II as ovelhas foram submetidas ao repasse com carneiros por 20 dias. O delineamento utilizado foi de blocos incompletos ao acaso, analisados pelo teste do Qui-quadrado e Tukey (estro). A taxa de detecção de estro no tratamento IATF (exp. III) foi de 59,7% sendo menor que os demais tratamentos (P<0,05). A taxa de prenhez da sincronização do tratamento MN (61,1%), foi maior (P<0,05) que os tratamentos IATF e IATF+GnRH. A inseminação artificial transcervical apresentou resultados médios que variaram de 21 a 35% e não apresentaram diferença (P>0,05). O efeito macho e o tipo de macho não apresentaram diferença na IATF. O protocolo de 11 dias, mostrou-se eficiente em induzir o estro em 79% das ovelhas sincronizadas. A IA realizada 12h após o estro propiciou, índice de prenhez semelhante à monta natural, proveniente do estro sincronizado. / In the 60s, estrus synchronization techniques began to be used, and during the last 30 years has attracted the interest of developing new methods to synchronize estrus in ewes. Three experiments were performed to determine: I) influence of male effect and type of teaser; II) Effect of new and used CIDR® (Control Internal Drug Release) with different time of implant; III) Different time to perform IA after CIDR removal and comparison of laparoscopy method with natural breed, on heat detection and onset of estrus and pregnancy rate of ewes. Exp. I: 270 ewes were used, divided into three treatments: SM = (control) without teaser; DL = teaser with lateral penis deviation and VS = vasectomized teaser. All ewes were subjected to the same protocol: CIDR® for 7 days and received im. 300UI of eCG plus 6.71 mg tromethamine dinoprost at CIDR withdrawal. Ewes were artificially inseminated by transcervical method, 55h after CIDR removal. There was no difference on onset of estrus for LD (55.7%) and VS (50.5%). Similarly, the distribution of estrus was similar (P>0.05) between treatments, where the averages were of 45:01 ± 14:30 h for LD 12:10 h and 44:00 ± 12:10h for VS. Pregnancy rate did not differ (P> 0.05) among treatments and was 34.0, 34.4 and 35.0% for LD, VS and SM, respectively. The male effect showed no influence on pregnancy rate when fixed-time artificial insemination was used. EXP.II: 275 ewes were used and divided into 4 treatments: 7N = 7d with new CIDR; 7U = 7d with already used CIDR for 7d; 11N = 11d with new CIDR; 11U = 11d with CIDR already used for 7d. On the withdrawal of the CIDR (D7 or D11) ewes received im. 300IU of eCG plus 6.71 mg tromethamine dinoprost at the time of CIDR removal. Ewes were submitted to FTAI, using the transcervical method, 49h after CIDR withdrawal. Total pregnancy rate in treatment 11N was higher (86.6%, P = 0.03) as compared with treatment 7U (71.4%). The protocols for estrus synchronization of 7 and 11d were effective in inducing the expression of estrus. The reuse of CIDR did not influence the rate of onset and average time to onset of estrus and pregnancy rate in the FTAI. Exp.III: 247 ewes were used and divided in four treatments: MN = ewes were synchronized and exposed to males during 20d; IATF = ewes were synchronized and inseminated by laparoscopy 48h after CIDR removal; AITF+GnRH= ewes were synchronized and inseminated by laparoscopy using 0.05 mg gonadorelin, when 50% of the ewes showed signs of estrus; AI = ewes received im. 300IU of eCG plus 6.71 mg tromethamine dinoprost at the time of CIDR removal and were inseminated by laparoscopy, 12h after the onset of signs of estrus. All treatments were subjected to the same protocol: CIDR for 11 days, intramuscular injection of 300UI of eCG plus 6.31 mg tromethamine dinoprost at CIDR removal. In all experiments ewes were exposed to rams (natural breeding), 10 days after FTAI. The experimental design was an incomplete randomized block, analyzed by chi- square and Tukey (estrus). The rate of detection of estrus in the treatment AITF (exp.III) was 59.7%, being lower than the other treatments (P <0.05). The pregnancy rate of the synchronization treatment MN (61.1%) was higher (P <0.05) that the treatments AITF and AITF+GnRH.Transcervical artificial insemination had average results that ranged from 21 to 35% and showed no difference (P> 0.05). The purpose and type of ram showed no difference in the AITF. The protocol of 11d, was effective in inducing estrus in the 79% of ewes synchronized. The IA conducted 12h after estrus provided, similar to pregnancy rate of natural builders, after the synchronization of estrus.

No description available.

I study dusty plasma produced by electrostatically confining melamine formaldehyde microparticles in a radio-frequency glow discharge plasma. Dusty plasma is a mixture of particles of solid matter (dust), electrons, ions, and neutral gas atoms. The dust particles have a very high charge and a mass compared to the electrons and ions in the ambient plasma. As a consequence, a dusty plasma exhibits collective phenomena such as dust acoustic waves, crystallization, and melting. The discrete nature of dust particles gives rise to compressibility. In this thesis I report findings of four tasks that were performed to investigate dust acoustic waves, compressibility, and melting. First, the nonlinear phenomenon of synchronization was characterized experimentally for the dust acoustic wave propagating in a dust cloud with many layers. I find four synchronized states, with frequencies that are multiples of 1, 2, 3, and 1/2 of the driving frequency. Comparing to phenomena that are typical of the van der Pol paradigm, I find that synchronization of the dust acoustic wave exhibits the signature of the suppression mechanism but not that of the phaselocking mechanism. Additionally, I find that the synchronization of the dust acoustic wave exhibits three characteristics that differ from the van der Pol paradigm: a threshold amplitude that can be seen in the Arnold tongue diagram, a branching of the 1:1 harmonic tongue at its lower extremity, and a nonharmonic state. Second, to assess which physical processes are important for a dust acoustic instability, I derived dispersion relations that encompass more physical processes than commonly done. I investigated how various physical processes affect a dust acoustic wave by solving these dispersion relations using parameters from a typical dust acoustic wave experiment. I find that the growth rate diminishes for large ion currents. I also find that the compressibility, a measure of the coupling between the dust particles, have a strong effect on the wave propagation. Comparing the kinetic vs. hydrodynamic descriptions for ions, I find that under typical laboratory conditions the inverse Landau damping and the ion-neutral collisions contribute about equally to the dust acoustic instability. Third, I performed dust acoustic wave experiments to resolve a previously unremarked discrepancy in the literature regarding the sign of the compressibility of a strongly-coupled dust component in a dusty plasma. According to theories compressibility is negative, whereas experiments suggest that it is positive. I find that the compressibility is positive. This conclusion was reached after allowing for a wide range of experimental uncertainties and model dependent systematic errors. Finally, the polygon construction method of Glaser and Clark was used to characterize crystallization and melting in a single-layer dusty plasma. Using particle positions measured in a previous dusty plasma experiment, I identified geometrical defects, which are polygons with four or more sides. These geometrical defects are found to proliferate during melting. I also identify a possibility of latent heat involvement in melting and crystallization processes of a dusty plasma.

Visual object tracking is a classical and very popular problem in computer vision with a plethora of applications such as vehicle navigation, human computer interface, human motion analysis, surveillance, auto-control systems and many more. Given the initial state of a target in the first frame, the goal of tracking is to predict states of the target over time where the states describe a bounding box covering the target. Despite numerous object tracking methods that have been proposed in recent years [1-4], most of these trackers suffer a degradation in performance mainly because of several challenges that include illumination changes, motion blur, complex motion, out of plane rotation, and partial or full occlusion, while occlusion is usually the most contributing factor in degrading the majority of trackers, if not all of them. This thesis is devoted to the advancement of generic object trackers tackling different challenges through different proposed methods. The work presented propose four new state-of-the-art trackers. One of which is 3D based tracker in a particle filter framework where both synchronization and registration of RGB and depth streams are adjusted automatically, and three works in correlation filters that achieve state-of-the-art performance in terms of accuracy while maintaining reasonable speeds.