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1

Koutsopoulos, Andreas [Verfasser]. "Dynamics and efficiency in topological self-stabilization / Andreas Koutsopoulos." Paderborn : Universitätsbibliothek, 2016. http://d-nb.info/1090965753/34.

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2

Cao, Hui. "Stabilization in wireless sensor networks." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1211079872.

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3

Cunado, Jose. "CONTROL AND STABILIZATION OF LASER PLASMASOURCES FOR EUV LITHOGRAPHY." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2746.

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Extreme Ultraviolet (EUV) sources rely on droplet laser plasmas for EUV generation. These sources consist of a small (30 &#956;m diameter) droplet which is excited into plasma emitting EUV around 13.5 nm, the industry's chosen wavelength for EUV lithography (EUVL). These sources are the best candidates for the commercialization of EUVL allowing mass production of computer chips with 32 nm or even smaller feature size. However, the biggest challenges which EUV source developers encounter today are the issues of conversion efficiency (CE) and debris.In order to satisfy the technology requirements, the source will need to meet high levels of stability, performance, and lifetime. Our tin-doped droplet plasma has demonstrated high CE and low debris resulting in long lifetime. Long term stability is obtained through the use of novel tracking techniques and active feedback. The laser plasma targeting system combines optical illumination and imaging, droplet technology innovation, advanced electronics, and custom software which act in harmony to provide complete stabilization of the droplets. Thus, a stable, debris-free light source combined with suitable collection optics can provide useful EUV radiation power. Detailed description of the targeting system and the evaluation of the system will be presented.<br>M.S.E.E.<br>School of Electrical Engineering and Computer Science<br>Engineering and Computer Science<br>Electrical Engineering MSEE
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4

Brown, Travis L. "Reaction wheel actuation for stabilization and efficiency improvement in planar bipeds." Thesis, University of Notre Dame, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10004967.

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<p> As robotic technology moves out of factories and into broader segments of society, it promises to support a revolutionary improvement in the general standard of living. One of the largest hurdles to this increased use of robotic technology, however, is the inability of current mobile robots to negotiate difficult and delicate terrain in ways that are fast, efficient, and safe. Examples in nature demonstrate the incredible potential of legged locomotion to fill this need, but legged robots have not yet reached this level of performance. This work moves the field toward a better understanding of the design of robust and efficient legged robots by exploring the concept of reaction wheel actuation. This concept consists of the generation of torques on the robot's body via a high efficiency reaction wheel system (RWS), which operates by accelerating an internal reaction mass. These torques can be used to both improve the stability of the robot and increase its walking efficiency when used in a coordinated manner. </p><p> Due to the complex multi-body dynamics of these systems, the effect of design changes on a given performance metric are difficult to estimate. Full body trajectory optimization via direct transcription was employed as the primary tool to better understand the role that an RWS can play in bipedal locomotion. The five-link planar biped ERNIE was used as a basis for this analysis. Combined with a model of motor and gear losses, this allowed energetic comparisons between a baseline ERNIE model and hypothetical RWS-equipped versions. This showed for the first time that a correctly designed RWS, requiring only a modestly sized reaction wheel and a motor with minimal gear loss, can lead to improved walking efficiency.</p><p> Extensive optimization over the full operational walking range showed that a reasonably sized RWS with realistic levels of regenerative efficiency can improve walking efficiency by 5-10% over most gaits. Comparison of resulting gaits revealed that optimal RWS use leads to better centroidal momentum regulation, which in turn reduces loads on joint motors in the legs. Simulations of the ERNIE model under virtual constraint control verified these results. For validation, an experimental reaction wheel system was constructed and attached to the ERNIE biped. Walking experiments with ERNIE demonstrated a measurable improvement in walking efficiency for gaits that utilize the RWS, corroborating the results from both optimization and simulation. </p><p> For periodic walking, optimization results showed that near regions of marginal dynamic feasibility, reaction wheels can lead to much larger efficiency gains than in more typical operating conditions. RWS use also expands the range of dynamically feasible motions. In aperiodic motions such as speed and step length changes, RWS use is similarly beneficial, with significant efficiency gains in very demanding motions and expanded dynamic feasibility. For large, single-step changes of speed, the RWS can improve efficiency by as much as 60%. When transitions are executed over longer, multi-step duration, RWS use provides benefits similar to those seen in periodic walking. </p><p> The potential role of reaction wheels in improving balance was also examined. Design principles for efficient RWS stabilization were derived by combining RWS-based balance controllers with accurate gear and motor models. Stabilization generally demands more RWS torque than steady state walking, but still favors relatively light gearing in order to minimize gear loss and maximize momentum storage potential. A task space controller for underactuated balancing was developed to compare baseline and RWS-equipped bipeds in terms of balance performance. While the RWS-equipped biped was able to balance and reject large disturbances, the baseline biped was only able to balance for short periods of time.</p>
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5

Morello, Alessandro. "Influence of ph and temperature on metatartaric acid efficiency in white wine tartaric stabilization." Master's thesis, ISA/UL, 2012. http://hdl.handle.net/10400.5/8625.

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Mestrado Vinifera EuroMaster - Instituto Superior de Agronomia<br>The sensitivity of metatartaric acid (MA) to high temperatures is the main limit for its actual use in enology. For this reason MA is generally used only for ready-to-drink wines that are stored for few months in bottle. The objective of this work was to obtain more information about the use of MA in order to prevent tartaric salts precipitation in wine by monitoring its effectiveness along the time. Tartaric stability was followed in a white wine during a ten-week experiment. 10 g/Hl of MA was added to wines with different five pH values, namely 3.0, 3.2, 3.5, 3.7 and 3.9 at room temperature (20°C), and to wines at original pH of 3.2 under three different temperatures commonly found in real storage conditions, precisely 12°C, 20°C and 35°C. To monitor tartaric stability we used a test based on the electrical conductivity developed by Boulton (1983). At the end of the experiment we found both a pH and a temperature effect. It was found a polynomial relation (R2 = 0,85) between tartaric stability and pH. The highest the pH, the highest the instability and the shortest the protection against tartrates precipitation. Furthermore, over 20°C we observed a rapid general decrease of MA effectiveness and that there was a linear relation (R2 = 0,99) between temperature and tartaric stability, so that we can affirm that the highest the temperature, the higher the wine instability; this is probably due to a faster MA hydrolysis. Metatartaric acid is surely able to prevent tartrates precipitation, but since in our experimental conditions it could not protect the wine for longer than one month, we would suggest extreme prudence about its use especially during long storage periods
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6

Neumann, Dirk Verfasser], Clemens [Akademischer Betreuer] [Fuest, and Felix [Akademischer Betreuer] Bierbrauer. "Tax-Transfer Systems in Europe: Between Efficiency, Redistribution and Stabilization / Dirk Neumann. Gutachter: Clemens Fuest ; Felix Bierbrauer." Köln : Universitäts- und Stadtbibliothek Köln, 2013. http://d-nb.info/1038710626/34.

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7

Neumann, Dirk [Verfasser], Clemens [Akademischer Betreuer] Fuest, and Felix [Akademischer Betreuer] Bierbrauer. "Tax-Transfer Systems in Europe: Between Efficiency, Redistribution and Stabilization / Dirk Neumann. Gutachter: Clemens Fuest ; Felix Bierbrauer." Köln : Universitäts- und Stadtbibliothek Köln, 2013. http://d-nb.info/1038710626/34.

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8

Zahorjan, Domicián. "Štátna pomoc finančnému sektoru vo vybraných krajinách v dobe finančnej krízy v rokoch 2007-2009." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-113258.

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This thesis is focused on financial crisis and its short-term solutions. Based on theoretical analysis of causes of crisis and solutions, the aim is to analyse financial crisis from years 2007-2009 on case studies of USA, United Kingdom, Germany and Ireland. Furthermore, the aim is to analyse efficiency and success of adopted stabilisation measures. Analysis of adopted measures is based on internationaly comparable indicators, such as capital power or loans creation in context of costs spent and economic performance. The conclusion is, that national governments were successful in stabilising financial sector, but the problems, which caused crisis, still remains unsolved and their solutions were only delayed. Thesis is also coming to conclusion, that smaller government interventions leads to stabilisation of financial sector with lower costs and smaller increase in moral hazard and thus in lower systemic risk.
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9

Stejskal, Tomáš. "Zlepšení postupů firmy při realizaci zakázek." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2008. http://www.nusl.cz/ntk/nusl-221813.

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This Master thesis deals with proposal of action improvements in company A-WebSys Ltd. while realizing their contracts. The thesis purpose is to minimize risks by future projects, enhance the effectiveness of realization and maintaining of current projects, minimize the employee fluctuation and enhance the overall stability of company. In accordance to this we have supported the thesis with theoretical knowledge and also have realized the analysis of current situation of the company and its environment. Shortcomings and problems identified are then solved by suggested changes each individually contributing to the situation improvement. Practical feasibility of proposed solution and profitability of expended costs is in conclusion proved by the economic assessment.
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Derue, Lionel. "Stabilisation thermique de la couche photo-active dʼune cellule solaire organique par réticulation". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00933501.

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Dans une configuration optimale, la couche photo-active d'une cellule solaire organique forme une hétérojonction volumique entre un matériau donneur et un matériau accepteur d'électrons. Cette morphologie optimale se trouve dans un état thermodynamique métastable. En cours de fonctionnement, l'absorption incidente provoque une élévation de la tempéra- ture des dispositifs. L'apport d'énergie thermique au système le fait évoluer vers un état thermodynamique stable correspondant à une micro-séparation de phase entre les deux matériaux nuisible aux performances photovoltaïques du dispositif. La solution à cette problématique envisagée dans cette thèse est de figer la morphologie optimale de la couche photo-active par réticulation chimique. Dans le but de prévenir la diffusion et la cristallisation des dérivés du fullerène, plusieurs approches ont été étudiées : la formation d'une maille de polymères réticulés, l'accroche des dérivés du fullerène aux chaînes du polymères ou la liaison entre plusieurs dérivés du fullerène. Les différentes fonctions réticulantes utilisées dans ces approches sont l'allyle, le cinnamate, l'anthracène et l'azoture. Au cours de ces travaux, des résultats satisfaisants ont été obtenus avec la fonction azoture. Basé sur cette fonction, nous avons développé un additif qui permet d'augmenter notablement la stabilité thermique des cellules solaires réticulées. Cette approche a été validée sur plusieurs couples de matériaux polymères/dérivés du fullerène à l'état de l'art.
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11

Sobers, David Michael Jr. "Efficient ranging-sensor navigation methods for indoor aircraft." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34824.

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Unmanned Aerial Vehicles are often used for reconnaissance, search and rescue, damage assessment, exploration, and other tasks that are dangerous or prohibitively difficult for humans to perform. Often, these tasks include traversing indoor environments where radio links are unreliable, hindering the use of remote pilot links or ground-based control, and effectively eliminating Global Positioning System (GPS) signals as a potential localization method. As a result, any vehicle capable of indoor flight must be able to stabilize itself and perform all guidance, navigation, and control tasks without dependence on a radio link, which may be available only intermittently. Since the availability of GPS signals in unknown environments is not assured, other sensors must be used to provide position information relative to the environment. This research covers a description of different ranging sensors and methods for incorporating them into the overall guidance, navigation, and control system of a flying vehicle. Various sensors are analyzed to determine their performance characteristics and suitability for indoor navigation, including sonar, infrared range sensors, and a scanning laser rangefinder. Each type of range sensor tested has its own unique characteristics and contributes in a slightly different way to effectively eliminate the dependence on GPS. The use of low-cost range sensors on an inexpensive passively stabilized coaxial helicopter for drift-tolerant indoor navigation is demonstrated through simulation and flight test. In addition, a higher fidelity scanning laser rangefinder is simulated with an Inertial Measurement Unit (IMU) onboard a quadrotor helicopter to enable active stabilization and position control. Two different navigation algorithms that utilize a scanning laser and techniques borrowed from Simultaneous Localization and Mapping (SLAM) are evaluated for use with an IMU-stabilized flying vehicle. Simulation and experimental results are presented for each of the navigation systems.
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Baptista, Felipe Derbli de Carvalho. "O Estado como investidor institucional: a disciplina jurídica de uma atuação estatal não interventiva na economia." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7922.

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Em um contexto de demandas sociais tendencialmente crescentes, uma das alternativas para o aumento da arrecadação de receitas pelo Estado reside no manejo de aplicações financeiras. Os investimentos financeiros estatais, a rigor, já acontecem, mas nem sempre o objetivo claro e explícito de obtenção de resultados financeiramente interessantes e, eventualmente ou mesmo por isso , sob gestão economicamente ineficiente. Às vezes, até se enxerga o foco na obtenção de rendimentos relevantes na ação estatal, mas sem uma disciplina específica, o que pode abrir espaço a uma gestão de ativos desqualificada ou mesmo fraudulenta, com sérios prejuízos aos cofres públicos e, em situações extremas, ampliação ainda maior das despesas públicas. O objetivo desta tese, portanto, é reconhecer que nem sempre o Estado atua na economia com propósito interventivo e que, na qualidade de investidor institucional vale dizer, de ente que tem o dever de proceder aos investimentos e às aplicações financeiras que digam com as melhores práticas de administração dos ativos públicos , precisa atuar sob o jugo de normas jurídicas claras, que permitam ao Estado ampliar suas receitas dentro de limites razoáveis de exposição a risco financeiro e disponibilizem aos órgãos de fiscalização e controle da Administração Pública as ferramentas necessárias para, também quanto a esse aspecto, aferir a eficiência da ação estatal. Para tanto, têm-se como pressupostos o anacronismo da resistência cultural às aplicações financeiras dos entes da Administração Pública e a noção de que quaisquer ferramentas de obtenção de receitas pelo Estado estão sujeitas a algum grau de risco. Com base nas bem-sucedidas experiências nacionais e internacionais, será possível concluir, ao final, que é admissível, do ponto de vista constitucional e legal, a ação do Estado como investidor nos mercados financeiro e de capitais e que é viável a formulação de parâmetros gerais para a disciplina jurídica do Estado investidor.<br>In a context of growing social demands, financial investments become one of the alternatives for the State to increase its revenues. State investments, as a matter of fact, already do happen, but not always with the clear and explicit objective of obtaining financially interesting earnings, often due economically inefficient management. Sometimes it is possible to see in government investments some focus on obtaining relevant income, but not under a specific regulation, which can lead to an unqualified or even fraudulent management that may cause serious damage to the exchequer and, in extreme situations, expansion of the government spending. Hence the intent of this thesis is to acknowledge that the State does not always act in the economy with regulatory purposes and that, as an institutional investor i.e., an organization which has the duty of making financial investments in accordance to the best practices in public asset management , it must be framed by clear legal rules, which should allow the State to maximize its revenues within reasonable limits of financial risk exposure and the oversight and control agencies to assess the State efficiency and compliance. It is assumed that the cultural resistance to state financial investments is anachronistic as well as every state means of obtaining revenues is subject to some level of financial risk. Based on well succeeded experiences in Brazil and abroad, it will be possible to conclude, in the end, that it is constitutionally and legally admissible that the State acts as an investor in financial and stock markets and that it is possible to suggest some standards on legal regulation for this issue.
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Rumple, Amber C. "Sustainable chemistry solutions for industrial challenges: mechanisms of PVC degradation and stabilization; reversible ionic liquids for CO₂ capture; efficient Suzuki coupling of basic, nitrogen containing substrates." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53474.

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The thermal degradation of polyvinyl chloride (PVC) is a significant processing challenge which can lead to deleterious mechanical and optical properties in a wide range of products. Synergetic studies on PVC model compounds and blends of bulk PVC provide unique insights into the thermal degradation and stabilization pathways in the presence of common additives. Model PVC compounds were selected to replicate specific defects (e.g., allylic, vicinal and tertiary) and tacticity (i.e., utilizing stereochemistry to investigate tacticity) commonly found in PVC. Model studies were conducted neat (solvent-free) with metal carboxylates. Experimental results highlight that the allylic and tertiary defects are more reactive than pristine PVC and isotactic sites are more reactive than their syndiotactic counterparts. Zinc stearate was found to act not in the role of substituent, but as a Lewis acid by facilitating dehydrochlorination of labile chlorides. This prevents the accumulation of hydrogen chloride and autocatalytic chain unzipping. In contrast, calcium stearate delayed the formation of zinc chloride, a much stronger Lewis acid than zinc stearate, through an ion exchange process to form calcium chloride. Thermal weight loss studies using blends of bulk PVC proved critical in transferring mechanistic insights into the context of a polymeric matrix. Post-combustion carbon capture has traditionally involved the use of aqueous alkanol amine solutions. The regeneration of such systems, however, can be costly and energy intensive. We have developed an alternative system utilizing silylated alkylamines to reversibly capture CO2 under near ambient conditions. The silyl amines developed capture CO2 through chemical reaction to form reversible ionic liquids (RevIL). RevILs utilize no added water and are tunable by molecular design allowing us to influence industrially relevant carbon capture properties such as viscosity, temperature of reversal, and enthalpy of regeneration, while maximizing overall CO2 capture capacity. We demonstrate a strong structure-property relationship among the silyl amines where minor structural modifications lead to significant changes in the bulk properties of the RevIL. Amine containing substrates are important building blocks for a variety of biological and pharmaceutical compounds. However, application of the otherwise versatile Suzuki reaction to these substrates has proved challenging due to either ligation of the amine to the palladium or to electronic effects slowing the oxidative addition step. Conventional methods to overcome these challenges involve protection-deprotection strategies or the use of designer ligands to facilitate reaction. We have shown that application of CO2 pressure and adjusting the water content of the reaction system facilitate the Suzuki coupling of 4-amino-2-halopyridines in high yield with the simple Pd(TPP)2Cl2 catalyst. The protocol was expanded to 2-halopyridines. The results of these investigations will be discussed.
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14

Loy, Kak Choon. "Efficient Semi-Implicit Time-Stepping Schemes for Incompressible Flows." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36442.

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The development of numerical methods for the incompressible Navier-Stokes equations received much attention in the past 50 years. Finite element methods emerged given their robustness and reliability. In our work, we choose the P2-P1 finite element for space approximation which gives 2nd-order accuracy for velocity and 1st-order accuracy for pressure. Our research focuses on the development of several high-order semi-implicit time-stepping methods to compute unsteady flows. The methods investigated include backward difference formulae (SBDF) and defect correction strategy (DC). Using the defect correction strategy, we investigate two variants, the first one being based on high-order artificial compressibility and bootstrapping strategy proposed by Guermond and Minev (GM) and the other being a combination of GM methods with sequential regularization method (GM-SRM). Both GM and GM-SRM methods avoid solving saddle point problems as for SBDF and DC methods. This approach reduces the complexity of the linear systems at the expense that many smaller linear systems need to be solved. Next, we proposed several numerical improvements in terms of better approximations of the nonlinear advection term and high-order initialization for all methods. To further minimize the complexity of the resulting linear systems, we developed several new variants of grad-div splitting algorithms besides the one studied by Guermond and Minev. Splitting algorithm allows us to handle larger flow problems. We showed that our new methods are capable of reproducing flow characteristics (e.g., lift and drag parameters and Strouhal numbers) published in the literature for 2D lid-driven cavity and 2D flow around the cylinder. SBDF methods with grad-div stabilization terms are found to be very stable, accurate and efficient when computing flows with high Reynolds numbers. Lastly, we showcased the robustness of our methods to carry 3D computations.
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Barbin, Émilie. "La régularisation des actes administratifs : étude de droit comparé franco-brésilien." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE3048.

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La régularisation des actes administratifs s’inscrit dans un mouvement global de recherche de stabilité juridique, mettant à l’épreuve la dialectique bien connue de la sécurité juridique et de la légalité administrative. Elle implique en effet que l’acte puisse subsister dans l’ordonnancement juridique, en dépit d’une illégalité originelle. Mais, l’état actuel du droit français de la régularisation des actes administratifs interpelle par le décalage existant entre la présence croissante de ses mentions en droit positif et l’indétermination de son emploi. À l’inverse, le législateur brésilien a consacré depuis vingt ans la régularisation des actes administratifs comme un pouvoir aux mains de l’administration, et fournit l’exemple d’une expérience mature de son utilisation. Le droit comparé se mobilise alors comme un outil de découverte autant que comme un révélateur des perspectives qui pourraient accompagner l’expansion de la régularisation en droit français. À partir de cette démarche, la notion a pu être précisée, désignant un processus de correction à effets rétroactifs, permettant de maintenir l’acte administratif dans l’ordonnancement juridique et de restaurer la légalité. Cette définition contribue à singulariser la notion et à en préciser le champ, permettant d’envisager ensuite ses effets juridiques. À cet égard, la construction d’un régime propre à la régularisation des actes administratifs a pour but d’en clarifier les implications juridiques. Ce régime repose alors sur la recherche d’un équilibre, en ce qu’il doit à la fois permettre de respecter les objectifs poursuivis par la régularisation et de contenir certains de ses effets négatifs, notamment à l’égard des tiers<br>The regularisation of administrative acts is part of a global search for legal stability, which calls into question the familiar dialectic between legal certainty and administrative legality. It implies that administrative acts can be retained in the legal system despite their original illegality. Yet the French current legal system is characterised by a striking discrepancy between increasing references to regularisation in positive law, and uncertainty around its usage. On the contrary, regularisation has been embedded in Brazil’s legal architecture for twenty years as a power resting with the administration, which provides us with an example of mature use of this process. In this context, comparative law is both a tool to learn more about regularisation and a means to examine the prospects that could accompany its expansion within the French legal system. This approach allows for a definition of this notion as a corrective process with retroactive effects, enabling administrative acts to be kept in the legal order and legality to be restored. This definition helps to specify the scope of the notion, which then enables us to consider its legal effects. In this respect, building a specific system for the regularisation of administrative acts aims at specifying its legal implications. This system rests on a balance between meeting the objectives pursued by regularisation and limiting some of its negative effects, in particular towards third parties
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Ramirez, Villalba Leidy catherine. "Towards an efficient modeling of Fluid-Structure Interaction." Thesis, Ecole centrale de Nantes, 2020. http://www.theses.fr/2020ECDN0029.

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Les applications industrielles FSI se caractérisent par des géométries et des matériaux complexes. Afin de prédire avec précision leur comportement, des coûts de calcul élevés sont associés, à la fois en temps et en ressources informatiques. Pour améliorer la qualité de la prédiction sans pénaliser le temps de calcul, et pour réduire le temps de calcul sans impacter la précision disponible aujourd'hui, deux axes principaux sont explorés dans ce travail. Le premier est l'étude d'un algorithme asynchrone qui pourrait permettre l'utilisation de modèles structurels complexes. Le second consiste à étudier la méthode des tranches en combinant l'utilisation d'un modèle RANS et d'un modèle FEM non linéaire. D'une part, l'étude de l'asynchronicité dans le domaine FSI a révélé différents aspect d'intérêt qui doivent être approfondis avant que l'approche puisse être utilisée industriellement. Cependant, un premier traitement des points mentionnés ci-dessus a montré des signe d'amélioration qui pourraient conduire à un algorithme prometteur, qui se situe naturellement entre l'algorithme explicite et l'algorithme implicite. D'autre part, il a été montré que la méthode des tranches développée dans ce travail conduit à une réduction significative du temps de calcul sans dégradation de la précision<br>FSI industrial applications are often described by complex geometries and materials. In order to accurately predict their behavior, high computational costs are associated, both in time and in computational resources. To improve the quality of the prediction without penalizing the computational time, and to reduce the computational time without impacting the accuracy that is available today, two main axes are explored in this work. The first one is the study of an asynchronous algorithm that could allow the use of complex structural models. The second axis consists of the study of the strip method while combining the use of a RANS model and a non-linear FEM model. On the one hand, the study of asynchronicity in the FSI domain revealed different aspects of interest that must be addressed before the approach can be used industrially. However, a first treatment of the limitations found showed signs of an improvement that could lead to a promising algorithm, one that naturally lies between the implicit external algorithm and the implicit internal algorithm. On the other hand, it was shown that the strip method developed in this work achieves a significant reduction in calculation time while maintaining excellent accuracy
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Huang, Ching-Ting, and 黃敬庭. "Evaluating the Efficiency of Sub-surface Drainages for the Slope Stabilization of Chai-San Landslide." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ae8367.

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碩士<br>國立屏東科技大學<br>水土保持系所<br>105<br>Chai-San is the back garden of Kaohsiung city. It was a military control area in the early stage, enjoying the beauty of the mountains and the sea, making the local tourism. The shallow layer is a Coral Reef in the Chai-San Area. The deep area is formed by the discontinuous surface of Mudstone, which is a very special topography and geological structure. Over time, the formation and displacement of the strata are caused by the waves sweeping beneath the slopes. According to the monitoring data showed that the landslide will be accompanied by heavy rain. The rainfall duration in Chai Shan region is mainly between May and October each year. Landslide presumably because of the concentrated rainfall, Strata are subjected to rainfall infiltration, resulting in higher groundwater levels, resulting in a weakening of the mudstone layer itself or the interface with limestone.Caused the Chai-Shan Landslide displacement toward of the Western finally. This study compiled the local Landslide Rainfall Drainage remediation materials and the Kaohsiung City Government and the Landslide monitoring data (from 2012 to 2015), the effectiveness of the project is compared with the formation slip data and the Rainfall data. The effectiveness of the treatment is discussed comprehensively, and the future management plan can be provided as a reference.
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Vicente, Ricardo Ranito. "Enhancing practice efficiency through contextual interference in youth football." Master's thesis, 2018. http://hdl.handle.net/10400.5/19426.

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To better understand how introducing variability in training could enhance motor skills learning, we compared a training approach without addition of variability in the practice conditions, with an approach with contextual interference in young football players. 12 athletes between the ages of 11 and 12 were divided into 2 groups, control (6) and experimental (6). The control group performed exercises with no variability in practice conditions and the experimental group performed exercises with contextual interference by series. They trained for 6 weeks, twice a week (30 minutes sessions), on ball control and shooting at goal tasks. Three evaluations were made, one initial, one intermediate and one final and were carried out two weeks apart. Both groups had the same amount of repetitions during the practice sessions. The experimental group improvement regarding ball control was statistically significant from the control group and the experimental group also hit the goal significantly more than the control group. These results allow us to suggest that adding variability to practice may lead to technical improvements in young football players and that variability in practice may potentialize an adaptive behavior to the environment.
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Cheng, Jen-Hao, and 鄭人豪. "A study on the Pb stabilization efficiency and mechanism during the wet ball milling for MSWI fly ash." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/12969777294604588787.

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碩士<br>淡江大學<br>水資源及環境工程學系碩士班<br>99<br>Municipal solid waste incinerator (MSWI) fly ash with high alkalinity, high chloride and heavy metals problems. The chlorine and heavy metal will form easily dissolved salts in fly ash. In this study, the water extraction procedure as a pre-treatment to remove plenty of chlorine salts. Then stability of heavy metals with wet ball milling technology. The study is to investigate heavy metal stabilization efficiency and mechanism during the wet ball milling for MSWI fly ash. And adding a known concentration of lead fluid in experimental. Observed the lead by mechano-chemical of change. According to the results of water-extracted fly ash leaching of heavy metals, the lead of the leached concentration was 9.76 mg/L. It was higher than with the USEPA regulatory limit of 5mg/L. Therefore, the future tendency is to discuss Pb stabilization by milling. According to the experimental results, stabilizing effect of lead using the mixing ratio of milling media 1:1(diameter of milling media is 1 and 5 mm respectively) is better than a single small diameter 1mm milling media. However, the mutual milling of the water-extracted fly ash and concentration 10g/L、40g/L lead fluid was 8 hours and then extractable lead by TCLP. The results show that 93%、82% of lead stabilization efficiency respectively. The water-extracted fly ash and concentration 40g/L lead fluid milled 0-20 hours. The results by XRD analysis showed with the long milled of the lead crystalline particles were hardly to identify. The observation of SEM indicates that milled fly ash to from solid solution which led the lead into fly ash to result in stabilization. According to mathematical projections, mechano-chemical treatment can increase 37-40% stabilization efficiency of heavy metals. Chemical reaction to form a stable compound that only 12% stabilization efficiency of heavy metals. The lead to form a stable adsorption can increase 18% stabilization efficiency of heavy metals. Finally, the results by XRD analysis showed the lead milled 8 hours. The predominant species of lead was identified to be Pb7O6Cl2 into insoluble state PbO2. Confirmed that mechano-chemical treatment can effectively inhibited the elution of lead from fly ash.
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20

Ndossi, Emanueli Mathayo. "Composition, degradation and stabilization of soil organic matter along an elevation gradient of Mount Kilimanjaro." Doctoral thesis, 2019. http://hdl.handle.net/21.11130/00-1735-0000-0005-152F-0.

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21

Vlasák, Martin. "Efektivita McGillovy metody při léčbě vertebrogenního algického syndromu." Master's thesis, 2020. http://www.nusl.cz/ntk/nusl-412269.

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Title: The effectiveness of McGill's method in the treatment of Vertebrogenic algic syndrome. Objectives: The goal of this thesis was to determine the applicability of McGill's method to patients with diagnoses, that are collectively referred to as Vertebrogenic algic syndrome by comparing the measured data of proband with different locations of diagnosis of Vertebrogenic algic syndrome in the Czech Republic. Methods: This is a pilot experimental research involving 10 probands diagnosed with Vertebrogenic algic syndrome in the cervical spine, 10 probands diagnosed with Vertebrogenic algic syndrome in the thoracic spine and 10 probands diagnosed with Vertebrogenic algic syndrome in the lumbar spine. Each participant underwent a kinesiological examination according to the McGill's principles together with a SF-36 questionnaire. Measured values were compared and provided a basis for testing the hypotheses. The thesis uses methods of research, observation, querying and comparison of collected data. Results: Using the statistical analysis of the measured data demonstrated a positive effect of the McGill's treatment in terms of reduced pain in probands suffering from Vertebrogenic algic syndrome in all investigated locations. Comparing the measured data of individual groups shown that the difference in...
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22

Ma, Ni. "Efficient Simulation and Performance Stabilization for Time-Varying Single-Server Queues." Thesis, 2019. https://doi.org/10.7916/d8-fjv9-zj35.

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This thesis develops techniques to evaluate and to improve the performance of single-server service systems with time-varying arrivals. The performance measures considered are the time-varying expected length of the queue and the expected customer waiting time. Time varying arrival rates are considered because they often occur in service systems. For example, arrival rates often vary significantly over the hours of each day and over the days of each week. Stochastic textbook methods do not apply to models with time-varying arrival rates. Hence new techniques are needed to provide high quality of service when stationary steady-state analysis is not appropriate. In contrast to the extensive recent literature on many-server queues with time-varying arrival rates, we focus on single-server queues with time-varying arrival rates. Single-server queues arise in real applications where there is no flexibility in the number of service facilities (servers). Different analysis techniques are required for single-server queues, because the two kinds of models exhibit very different performance. Many-server models are more tractable because methods for highly tractable infinite-server models can be applied. In contrast, single-server models are more complicated because it takes a long time to respond to a build up of workload when there is only one server. The thesis is divided into two parts: simulation algorithms for performance evaluation and service-rate controls for performance stabilization. The first part of the thesis develops algorithms to efficiently simulate the single-server time-varying queue. For the generality considered, no explicit mathematical formulas are available for calculating performance measures, so simulation experiments are needed to calculate and evaluate system performance. Efficient algorithms for both standard simulation and rare-event simulation are developed. The second part of the thesis develops service-rate controls to stabilize performance in the time-varying single-server queue. The performance stabilization problem aims to minimize fluctuations in mean waiting times for customers coming at different times even though the arrival rate is time-varying. A new service rate control is developed, where the service rate at each time is a function of the arrival rate function. We show that a specific service rate control can be found to stabilize performance. In turn, that service rate control can be used to provide guidance for real applications on optimal changes in staffing, processing speed or machine power status over time. Both the simulation experiments to evaluate performance of alternative service-rate controls and the simulation search algorithm to find the best parameters for a damped time-lag service-rate control are based on efficient performance evaluation algorithms in the first part of the thesis. In Chapter Two, we present an efficient algorithm to simulate a general non-Poisson non-stationary point process. The general point process can be represented as a time transformation of a rate-one base process and by exploiting a table of the inverse cumulative arrival rate function outside of simulation, we can efficiently convert the simulated rate-one process into the simulated general point process. The simulation experiments can be conducted in linear time subject to small error bounds. Then we can apply this efficient algorithm to generate the arrival process, the service process and thus to calculate performance measures for the G_t/G_t/1 queues, which are single-server queues with time-varying arrival rates and service rates. Service models are constructed for this purpose where time-varying service rates are specified separately from the rate-one service requirement process, and service times are determined by equating service requirements with integrals of service rates over a time period equal to the service time. In Chapter Three, we develop rare-event simulation algorithms in periodic GI_t/GI/1 queues and further in GI_t/GI_t/1 queues to estimate probabilities of rare but important events as a sanity check of the system, for example, estimating the probability that the waiting time is very long. Importance sampling, specifically exponential tilting, is required to estimate rare-event probabilities because in standard simulation, the number of experiments may blow up to achieve a targeted relative error and for each experiment, it may take a very long time to determine that the rare event does not happen. To extend the rare-event simulation algorithm to periodic queues, we derive a convenient expression for the periodic steady-state virtual waiting time. We apply this expression to establish bounds between the periodic workload and the steady-state workload in stationary queues, so that we can prove that the exponential tilting algorithm with the same parameter efficient in stationary queues is efficient in the periodic setting as well, which has a bounded relative error. We apply this algorithm to compute the periodic steady-state distribution of reflected periodic Brownian motion with support of a heavy-traffic limit theorem and to calculate the periodic steady-state distribution and moments of the virtual waiting time. This algorithm's advantage in calculating these distributions and moments is that it can directly estimate them at a specific position of the cycle without simulating the whole queueing process until steady state is reached for the whole cycle. In Chapter Four, we conduct simulation experiments to validate performance of four service-rate controls: the rate-matching control, which is directly proportional to the arrival rate, two square-root controls related to the square root staffing formula and the square-root control based on the mean stationary waiting time. Simulations show that the rate-matching control stabilizes the queue length distribution but not the virtual waiting time. This is consistent with established theoretical results, which follow from the observation that with rate-matching control, the queueing process becomes a time transformation of the stationary queueing process with constant arrival rates and service rates. Simulation results also show that the two square-root controls analogous to the server staffing formula are not effective in stabilizing performance. On the other hand, the alternative square-root service rate control based on the mean stationary waiting time approximately stabilizes the virtual waiting time when the cycle is long so that the arrival rate changes slowly enough. In Chapter Five, since we are mostly interested in stabilizing waiting times in more common scenarios when the traffic intensity is not close to one or when the arrival rate does not change slowly, we develop a damped time-lag service-rate control that performs fairly well for this purpose. This control is a modification of the rate-matching control involving a time lag and a damping factor. To find the best parameters for this control, we search over reasonable intervals for the most time-stable performance measures, which are computed by the extended rare-event simulation algorithm in GI_t/GI_t/1 queue. We conduct simulation experiments to validate that this control is effective for stabilizing the expected steady-state virtual waiting time (and its distribution to a large extent). We also establish a heavy-traffic limit with periodicity in the fluid scale to provide theoretical support for this control. We also show that there is a time-varying Little's law in heavy-traffic, which implies that this control cannot stabilize the queue length and the waiting time at the same time.
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23

Di, Profio Pietro, Simone Arca, Raimondo Germani, and Gianfranco Savelli. "NOVEL NANOTECHNOLOGY FOR EFFICIENT PRODUCTION OF BINARY CLATHRATE HYDRATES OF HYDROGEN AND OTHER COMPOUNDS." 2008. http://hdl.handle.net/2429/2296.

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The efficient production of hydrogen hydrates is a major goal in the attempt to exploit those materials as an alternative means for storing hydrogen. Up to now, a few processes have been reported in the literature which yield less than 1 wt% of hydrogen stored into clathrate hydrate or semi-clathrate forms. One main obstacle to the entrapment of sensible amounts of hydrogen (i.e., up to 4 wt% ) into a clathrate matrix appears to be of a kinetic origin, in that the mass transfer of hydrogen gas into clathrate structures is drastically limited by the (relatively) macroscopic scale of the gas-liquid or gas-ice interfaces involved. In this communication, we present a novel process for an enhanced production of binary hydrates of hydrogen and other hydrate-forming gases, which is characterized by the use of nanotechnology for reducing the size of hydrate particles down to a few nanometers. This drastic reduction of particle size, down to three orders of magnitude smaller than that obtainable by macroscopic methods, allows to reduce the kinetic hindrance to hydrate formation. This process has a huge potential for increasing the amount of hydrogen stored, as it has provided ca. 1 wt% of hydrogen, with THF as a co-former. The present process also allows to use several non-water soluble coformers; first reports of hydrogen/cyclopentane and hydrogen/tetrahydrothiophene hydrates are presented.
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