Дисертації з теми "Algorithm stability"
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Chan, Chok You. "Stability and robustness of adaptive pole-zero placement algorithm." Thesis, University of Canterbury. Electrical Engineering, 1987. http://hdl.handle.net/10092/6017.
Повний текст джерелаHao, Zhaopeng. "High-order numerical methods for integral fractional Laplacian: algorithm and analysis." Digital WPI, 2020. https://digitalcommons.wpi.edu/etd-dissertations/612.
Повний текст джерелаGundu, Pavan Kumar. "Trajectory Tracking Control of Unmanned Ground Vehicles using an Intermittent Learning Algorithm." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/93213.
Повний текст джерелаMaster of Science
A risen research effort in the area of autonomous vehicles has been witnessed in the past few decades because these systems improve safety, comfort, transport time and energy consumption which are some of the main issues humans are facing in the modern world’s highway systems. Systems like emergency braking, automatic parking, blind angle vehicle detection are creating a safer driving environment in populated areas. Advanced driver assistance systems (ADAS) are what such kind of systems are known as. An extension of these partially automated ADAS are vehicles with fully automated driving abilities, which are able to drive by themselves without any human involvement. An extensively proposed approach for making traffic throughput more efficient on existing highways is to assemble autonomous vehicles into platoons. Small intervehicle spacing and many vehicles constituting each platoon formation improve the traffic throughput significantly. Lately, the advancements in computational capabilities, in terms of both algorithms and hardware, communications, and navigation and sensing devices contributed a lot to the development of autonomous systems (both single and multiagent) that operate with high reliability in uncertain/dynamic operating conditions and environments. Motion control is an important area in the autonomous vehicles research. Trajectory-tracking is a widely studied motion control scenario which is about designing control laws that force a system to follow some time-dependent reference path and it is important to have an effective and efficient trajectory-tracking control law in an autonomous vehicle to reduce the resources consumed and tracking error. The goal of this work is to design an intermittent model-free trajectory tracking control algorithm where there is no need of any mathematical model of the vehicle system being controlled and which can reduce the controller updates by allowing the system to evolve in an open loop fashion and close the loop only when an user defined triggering condition is satisfied. The approach is energy efficient in that the control updates are limited to instances when they are needed rather than unnecessary periodic updates. Q-learning which is a model-free reinforcement learning technique is used in the trajectory tracking motion control algorithm to make the vehicles track their respective reference trajectories without any requirement of their motion model, the knowledge of which is generally needed when dealing with a motion control problem. The testing of the designed algorithm in simulations and experiments is presented in this work. The study and development of a vehicle platform in order to perform the experiments is also discussed. Different motion control and sensing techniques are presented and used. The vehicle platform is shown to track a reference trajectory autonomously without any human intervention, both in simulations and experiments, proving the effectiveness of the proposed algorithm.
Hasanović, Amer. "A simulation and analysis toolbox for power systems and genetic algorithm based damping controller design." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2173.
Повний текст джерелаTitle from document title page. Document formatted into pages; contains viii, 73 p. : ill. Includes abstract. Includes bibliographical references (p. 71-73).
Fu, Xuezheng. "Structure Pattern Analysis Using Term Rewriting and Clustering Algorithm." Digital Archive @ GSU, 2007. http://digitalarchive.gsu.edu/cs_diss/17.
Повний текст джерела麥禮安 and Lai-on Mak. "Fuzzy logic statcom controller design with genetic algorithm application for stability enhancement of interconnected power systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B42128699.
Повний текст джерелаMak, Lai-on. "Fuzzy logic statcom controller design with genetic algorithm application for stability enhancement of interconnected power systems." Click to view the E-thesis via HKUTO, 2000. http://sunzi.lib.hku.hk/hkuto/record/B42128699.
Повний текст джерелаEr, Aynur. "Stability of Linear Difference Systems in Discrete and Fractional Calculus." TopSCHOLAR®, 2017. http://digitalcommons.wku.edu/theses/1946.
Повний текст джерелаHopkins, Brad Michael. "Adaptive Rollover Control Algorithm Based on an Off-Road Tire Model." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/36129.
Повний текст джерелаMaster of Science
NAGA, SOUMYA. "AN EFFICIENT ALGORITHM FOR CLINICAL MASS CENTER LOCATION OF HUMAN BODY." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1131323551.
Повний текст джерелаTbaileh, Ahmad Anan. "Robust Non-Matrix Based Power Flow Algorithm for Solving Integrated Transmission and Distribution Systems." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/89362.
Повний текст джерелаPHD
Ebrinc, Ali Aslan. "High Speed Viscous Plane Couette-poiseuille Flow Stability." Phd thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12604769/index.pdf.
Повний текст джерела#65533
s viscosity law are studied using a second-order finite difference scheme. The basic velocity and temperature distributions are perturbed by a small-amplitude normalmode disturbance. The small-amplitude disturbance equations are solved numerically using a global method using QZ algorithm to find all the eigenvalues at finite Reynolds numbers, and the incompressible limit of these equations is investigated for Couette-Poiseuille flow. It is found that the instabilities occur, although the corresponding growth rates are often small. Two families of wave modes, Mode I (odd modes) and Mode II (even modes), were found to be unstable at finite Reynolds numbers, where Mode II is the dominant instability among the unstable modes for plane Couette flow. The most unstable mode for plane Couette &
#65533
Poiseuille flow is Mode 0, which is not a member of the even modes. Both even and odd modes are acoustic modes created by acoustic reflections between a will and a relative sonic line. The necessary condition for the existence of such acoustic wave modes is that there is a region of locally supersonic mean flow relative to the phase speed of the instability wave. The effects of viscosity and compressibility are also investigated and shown to have a stabilizing role in all cases studied. Couette-Poiseuille flow stability is investigated in case of a choked channel flow, where the maximum velocity in the channel corresponds to sonic velocity. Neutral stability contours were obtained for this flow as a function if the wave number,Reynolds number and the upper wall Mach number. The critical Reynolds number is found as 5718.338 for an upper wall Mach number of 0.0001, corresponding to the fully Poiseuille case.
Singh, Ravindra. "A Novel Approach for Tuning of Power System Stabilizer Using Genetic Algorithm." Thesis, Indian Institute of Science, 2004. http://hdl.handle.net/2005/65.
Повний текст джерелаAltamirano, Chavez Armando. "An efficient algorithm using Householder's formulas for the solution of faulted power systems." Thesis, Kansas State University, 1986. http://hdl.handle.net/2097/9896.
Повний текст джерелаMarutani, Kyohei. "Essays on the Theory of Indivisible Good Markets." Kyoto University, 2020. http://hdl.handle.net/2433/253062.
Повний текст джерелаRust, Ian Charles. "Control of a nonlinear underactuated system with adaptation, numerical stability verification, and the use of the LQR Trees algorithm." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59934.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (p. 54).
Underactuated robotics, though surrounded by an established body of work, has certain limitations when nonlinear adaptive control principles are applied. This thesis applies a nonlinear adaptative controller that avoids many of these limitations using alterations inspired by the control of a similar underactuated system, the cart-pole. Due to the complexity of the system, a sums-of-squares MATLAB toolbox is used to generate a suitable Lyapunov Candidate used for proofs of stability, with claims of local stability made using Barbalat's Lemma. This provides us with a local domain of attraction for the altered classical nonlinear adaptive controller. In addition, the algorithm known as LQR Trees is applied to the system in order to create a controller with a larger region of attraction and lower torque requirements, though without an adaptive component. Both control systems are implemented in simulations using MATLAB.
by Ian Charles Rust.
S.B.
Miotto, Ednei Luiz. "Aplicação do algoritmo bioinspirado Novel Bat Algorithm na parametrização dos controladores suplementares de amortecimento e dispositivo FACTS GUPFC." Ilha Solteira, 2018. http://hdl.handle.net/11449/157493.
Повний текст джерелаResumo: Este trabalho apresenta o Novel Bat Algorithm com uma nova técnica para realizar o ajuste coordenado dos parâmetros de controladores suplementares de amortecimento (Estabilizadores de Sistemas de Potência e do conjunto Generalized Unified Power Flow Controller – Power Oscillation Damping) em sistemas elétricos de potência multimáquinas. O objetivo principal é inserir amortecimento adicional aos modos oscilatórios de baixa frequência e, consequentemente, garantir a estabilidade do sistema elétrico frente a pequenas perturbações. Para representar o sistema elétrico de potência será utilizado o Modelo de Sensibilidade de Potência. Desse modo, todos os seus dispositivos e componentes foram modelados por injeções de potência. Análises estáticas e dinâmicas foram realizadas em dois sistemas teste, sendo: o Sistema Simétrico de Duas Áreas e o Sistema New England. A eficiência do dispositivo FACTS Generalized Unified Power Flow Controller atuando em conjunto com uma estrutura de controle baseada em controladores Proporcional – Integral foi criteriosamente avaliada para o controle de fluxos de potências ativa e reativa, para a melhoria do perfil de tensão do sistema elétrico e na redução das perdas no sistema de transmissão. O desempenho do Novel Bat Algorithm, no que concerne ao ajuste dos parâmetros dos controladores, foi comparado a outros quatro algoritmos bio-inspirados bastante difundidos na literatura: Particle Swarm Optimization, Bacterial Foragim Optimization, Bat Algorithm e... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This work presents the Novel Bat Algorithm as a new technique for the to perform the coordinated tuning of the parameters of the supplementary damping controllers (Power Systems Stabilizers and Generalized Unified Power Flow Controller - Power Oscillation Damping) in multi-machine electric power systems. The main objective is to insert damping to low-frequency oscillations and thus ensure the stability of the electrical system against minor disturbances. The Power Sensitivity Model is used to represent the system. Thus, all devices and their components are modeled by power injection. Static and dynamic analyzes were performed in the two systems: the two-areas symmetric, and the New England. The performance of the proposed methodology (Novel Bat Algorithm), for tuning of the parameters of the controllers was compared to four other algorithms, presented in the literature: The Particle Swarm Optimization method, Bacterial Foraging Optimization method, Bat Algorithm method and a Genetic Algorithm with elitism. The results demonstrated that the Novel Bat Algorithm was more effective than the other techniques presented, generating robust solutions when variations on the scenarios of loads were considered, and therefore accredited it as a tool in the analysis of the study of small-signal stability.
Doutor
Kangas, M. (Maria). "Stability analysis of new paradigms in wireless networks." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526215464.
Повний текст джерелаTiivistelmä Langattomien kanavien häipyminen, langattomien laitteiden akkujen rajallinen koko, käyttäjien käyttötarpeiden muutokset sekä lisääntyvän tiedonsiirron ja lyhyemmän viiveen vaatimukset luovat suuria haasteita tulevaisuuden langattomien verkkojen suunnitteluun. On välttämätöntä kehittää tehokkaita resurssien allokointialgoritmeja, jotka sopeutuvat verkkojen muutoksiin ja saavuttavat sekä tavoiteviiveen että tavoitedatanopeuden mahdollisimman pienellä tehon kulutuksella. Tässä väitöskirjassa esitetään uusia paradigmoja langattomille tietoliikenneverkoille. Dynaamisen ohjelmoinnin välineitä käytetään luomaan dynaamisia verkon stabiloivia resurssien allokointiratkaisuja virtuaalisille pilvipalveludatakeskuksille, käyttäjien yhteistyöverkoille ja heterogeenisille verkoille. Tarkkoja dynaamisen ohjelmoinnin välineitä käytetään kehittämään optimaalisia resurssien allokointi ja topologian kontrollointialgoritmeja näille jonojen ja häipyvien kanavien verkoille. Tämän lisäksi, estimoituja dynaamisen ohjelmoinnin välineitä käytetään luomaan uusia alioptimaalisia ratkaisuja. Yhtenäisiä systeemimalleja ja yhtenäisiä kontrollointiongelmia luodaan sekä toissijaisen ja ensisijaisen palvelun tuottajan kognitiivisille verkoille että tavallisille langattomille verkoille. Tulokset osoittavat että sopeutumalla jonojen pituuksien ja kanavien muutoksiin dynaaminen tekniikka vaimentaa ensisijaisen ja toissijaisen palvelun tuottajien kognitiivisten verkkojen vaikutusta toisiinsa. Tutkimme myös verkon stabiiliutta ja luomme uusia stabiilisuusalueita sekä ensisijaisen ja toissijaisen palveluntuottajan kognitiivisille verkoille että tavallisille langattomille verkoille. K:n askeleen Lyapunovin driftiä käytetään analysoimaan dynaamisen kontrollointitekniikan suorituskykyä ja stabiiliutta. Lisäksi uusi yhtenäinen stabiiliusanalyysi ja jonon yläraja luodaan ensisijaisen ja toissijaisen palveluntuottajan kognitiivisille verkoille ja tavallisille langattomille verkoille. Dynaamisen algoritmin näytetään stabiloivan verkko ja minimoivan keskimääräisen jonon pituuden yläraja sopeutumalla verkon olosuhteiden muutoksiin. Tämän lisäksi todistamme että aiemmin esitetty frame-algoritmi ei minimoi keskimääräisen viiveen ylärajaa, kun käyttäjät jakavat keskenään resursseja
Westin, Robin. "Three material decomposition in dual energy CT for brachytherapy using the iterative image reconstruction algorithm DIRA : Performance of the method for an anthropomorphic phantom." Thesis, Linköpings universitet, Institutionen för medicinsk teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-91297.
Повний текст джерелаZhang, Hongbo. "Use of Statistical Mechanics Methods to Assess the Effects of Localized muscle fatigue on Stability during Upright Stance." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/30888.
Повний текст джерелаMaster of Science
Ramarathinam, Venkatesh. "A control layer algorithm for ad hoc networks in support of urban search and rescue (USAR) applications." [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000604.
Повний текст джерелаTastan, Mesut. "Analysis And Prediction Of Gene Expression Patterns By Dynamical Systems, And By A Combinatorial Algorithm." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606672/index.pdf.
Повний текст джерелаs method. Herewith, for stability analysis we apply modified Brayton and Tong algorithm to time-discrete dynamics in an extended space.
Peltonen, Joanna. "Development of effective algorithm for coupled thermal-hydraulics : neutron-kinetics analysis of reactivity transient." Licentiate thesis, Stockholm : Skolan för teknikvetenskap, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11033.
Повний текст джерелаYilmaz, Ali Emre. "Implementation Of Turbulence Models On 2d Hybrid Grids Using An Explicit/implicit Multigrid Algorithm." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613783/index.pdf.
Повний текст джерелаManmek, Thip Electrical Engineering & Telecommunications Faculty of Engineering UNSW. "Real-time power system disturbance identification and its mitigation using an enhanced least squares algorithm." Awarded by:University of New South Wales. Electrical Engineering and Telecommunications, 2006. http://handle.unsw.edu.au/1959.4/26233.
Повний текст джерелаDargahi, Kafshgarkolaei Mahdi. "Stability analysis and implementation of Power-Hardware-in-the-Loop for power system testing." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/81957/1/Mahdi_Dargahi%20Kafshgarkolaei_Thesis.pdf.
Повний текст джерелаLi, Zhe. "Développement d'une méthode de simulation de couplage fluide-structure à l'aide de la méthode SPH." Thesis, Ecully, Ecole centrale de Lyon, 2013. http://www.theses.fr/2013ECDL0036/document.
Повний текст джерелаThe Fluid-Structure Interaction (FSI) effects are of great importance for many multi-physical problems in academic researches as well as in engineering sciences. Various types of numerical simulation approaches may be used to investigate the FSI problems in order to get more reliable conception and to avoid unexpected disasters. In this work, the fluid sub-domain is simulated by a hybrid mesh-less method (SPH-ALE), and the structure is discretized by the Finite Element (FE) method. As the fluid is considered as a set of particles, one can easily track the fluid structure interface. An energy-conserving coupling strategy is proposed for transient fluid-structure interaction problems where different time integrators are used for each sub-domain: 2nd order Runge-Kutta scheme for the fluid and Newmark time integrator for the solid. By imposing a normal velocity constraint condition at the interface, this proposed coupling method ensures that neither energy injection nor energy dissipation will occur at the interface so that the interface energy is rigorously zero during the whole period of numerical simulation. This coupling method thus ensures that the coupling simulation shall be stable in time, and secondly, the numerical simulation will converge in time with the minimal convergence rate of all the time integrators chosen for each sub-domain. The proposed method is first applied to a mono-dimensional piston problem in which we verify that this method does not degrade the order of accuracy in time of the used time integrators. Then we use this coupling method to investigate the phenomena of propagation of shock waves across the fluidstructure interface. A good agreement is observed between the numerical results and the analytical solutions in the 1-D shock wave propagation test cases. Finally, some multi-dimensional examples are presented. The results are compared with the ones obtained by other coupling approaches
Brum, Vinicius Campista. "Análise de agrupamento e estabilidade para aquisição e validação de conhecimento em bases de dados de alta dimensionalidade." Universidade Federal de Juiz de Fora (UFJF), 2015. https://repositorio.ufjf.br/jspui/handle/ufjf/4826.
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Análise de agrupamento é uma tarefa descritiva e não-supervisionada de mineração de dados que utiliza amostras não-rotuladas com o objetivo de encontrar grupos naturais, isto é, grupos de amostras fortemente relacionadas de forma que as amostras que per-tençam a um mesmo grupo sejam mais similares entre si do que amostras em qualquer outro grupo. Avaliação ou validação é considerada uma tarefa essencial dentro da análise de agrupamento. Essa tarefa apresenta técnicas que podem ser divididas em dois tipos: técnicas não-supervisionadas ou de validação interna e técnicas supervisionadas ou de va-lidação externa. Trabalhos recentes introduziram uma abordagem de validação interna que busca avaliar e melhorar a estabilidade do algoritmo de agrupamento por meio de identificação e remoção de amostras que são consideradas prejudiciais e, portanto, de-veriam ser estudadas isoladamente. Por meio de experimentos foi identificado que essa abordagem apresenta características indesejáveis que podem resultar em remoção de todo um grupo e ainda não garante melhoria de estabilidade. Considerando essas questões, neste trabalho foi desenvolvida uma abordagem mais ampla utilizando algoritmo genético para análise de agrupamento e estabilidade de dados. Essa abordagem busca garantir melhoria de estabilidade, reduzir o número de amostras para remoção e permitir que o usuário controle o processo de análise de estabilidade, o que resulta em maior aplicabi-lidade e confiabilidade para tal processo. A abordagem proposta foi avaliada utilizando diferentes algoritmos de agrupamento e diferentes bases de dados, sendo que uma base de dados genotípicos também foi utilizada com o intuito de aquisição e validação de conhe-cimento. Os resultados mostram que a abordagem proposta é capaz de garantir melhoria de estabilidade e também é capaz de reduzir o número de amostras para remoção. Os resultados também sugerem a utilização da abordagem como uma ferramenta promissora para aquisição e validação de conhecimento em estudos de associação ampla do genoma (GWAS). Este trabalho apresenta uma abordagem que contribui para aquisição e valida-ção de conhecimento por meio de análise de agrupamento e estabilidade de dados.
Clustering analysis is a descriptive and unsupervised data mining task, which uses non-labeled samples in order to find natural groups, i.e. groups of closely related samples such that samples within the same cluster are more similar than samples within the other clusters. Evaluation and validation are considered essential tasks within the clustering analysis. These tasks present techniques that can be divided into two kinds: unsuper-vised or internal validation techniques and supervised or external validation techniques. Recent works introduced an internal clustering validation approach to evaluate and im-prove the clustering algorithm stability through identifying and removing samples that are considered harmful and therefore they should be studied separately. Through experi-mentation, it was identified that this approach has two undesirable characteristics, it can remove an entire cluster from dataset and still decrease clustering stability. Taking into account these issues, in this work a broader approach was developed using genetic algo-rithm for clustering and data stability analysis. This approach aims to increase stability, to reduce the number of samples for removal and to allow the user control the stability analysis process, which gives greater applicability and reliability for such process. This approach was evaluated using different kinds of clustering algorithm and datasets. A genotype dataset was also used in order to knowledge acquisition and validation. The results show the approach proposed in this work is able to increase stability, and it is also able to reduce the number of samples for removal. The results also suggest the use of this approach as a promising tool for knowledge acquisition and validation on genome-wide association studies (GWAS). This work presents an approach that contributes for knowledge acquisition and validation through clustering and data stability analysis.
Mims, Mark McGrew. "Dynamical stability of quantum algorithms /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004342.
Повний текст джерелаTisseur, Françoise. "Méthodes numériques pour le calcul d'éléments spectraux : étude de la précision, la stabilité et la parallélisation." Saint-Etienne, 1997. http://www.theses.fr/1997STET4006.
Повний текст джерелаCastoldi, Marcelo Favoretto. "Algoritmo híbrido para projeto de controladores de amortecimento de sistemas elétricos de potência utilizando algoritmos genéticos e gradiente descendente." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/18/18154/tde-07042011-151406/.
Повний текст джерелаElectric Power Systems are constantly subjected to perturbations, which can be caused for several different reasons, e.g., due to a sudden load increase or a short circuit in a transmission line. These perturbations can induce electromechanical oscillations in the power system, since the angular speed of the generators oscillates. To reduce such oscillations, power system controllers are used, and the most common ones are the PSSs (Power System Stabilizers). In some systems, however, the usage of PSSs is not sufficient to guarantee a satisfactory level for the minimum damping, being necessary the usage of other types of controllers. Hence, FACTS (Flexible Alternating Current Transmission System) controllers, specially the TCSC (Thyristor Controlled Series Capacitor), became an attractive alternative to enhance the damping of electric power systems. The TCSC control action is performed by a POD (Power Oscillation Damper) controller, which is a supplementary control function of the device. However, it is not only the usage of such controllers that guarantees a sufficient damping, but also a good tuning of their parameters. The tuning of such controllers is ordinarily performed manually, using a trial-and-error method, which can last for a long time, even for experienced engineers. To facilitate the designers work in the tuning of the controllers parameters, automatic tuning methods are being studied. Such methods have the main advantage of considering several operating points of the system simultaneously, yielding a robust controller regarding variations in its nominal operating point. The aforementioned automatic tuning methods use local optimization methods or global optimization methods. The local optimization methods have the speed as the main advantage, but they can have convergence issues in the search for the minimum satisfactory damping threshold desired by the designer. The global optimization methods, on the other hand, ordinarily converge for the desired minimum damping threshold, but with large convergence times. This work proposes a controller tuning method using a hybrid structure, i.e., global search methods with local search methods. Initially, a global search is performed by the algorithm until a stop criteria is met, as defined by the designer (usually a minimum damping for the system). Thus, the controller parameters tuned by the global search method are the input values of a local search method. The local search algorithm actually refines the controllers tuning, increasing the system damping to the value defined by the designer. In this work the global search is performed by a genectic algorithm while the local search is performed by an algorithm based in the gradient descent of objective function (damping in this case). The greatest advantages of the proposed algorithm are the possible decrease in computational time and effort, when compared to global search methods, verified in the work results.
Marenych, M. S. "Procedures analysis for evaluating resistance of passwords." Thesis, Київський національний університет технологій та дизайну, 2019. https://er.knutd.edu.ua/handle/123456789/14358.
Повний текст джерелаКондіус, І. С. "Алгоритм побудови комплексної агрегованої моделі стійкого розвитку регіону". Thesis, ДИАЙПИ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/63603.
Повний текст джерелаIn a study author proposed algorithm for constructing complex aggregate model of sustainable development in the region.
Ghamrawi, Ahmad. "Optimisation et gestion des flux énergétiques d'un générateur solaire photovoltaïque." Thesis, Poitiers, 2018. http://www.theses.fr/2018POIT2304.
Повний текст джерелаThis thesis in part of research thematic dedicated to photovoltaic solar energy production's systems. In fact, energy demands in the world are continuously increasing, the fossil fuels exploitation depletes limited sources and impact our environment. Solar photovoltaic energy represents one of the most promoted renewable energy sources, even if its drawbacks remain its installation’s high initial cost and its production’s variability. The main object of the presented work is to optimize the global efficiency of a stand-alone photovoltaic system. In that respect, this research focuses on the architecture of the conversion chain by integrating DC-DC conventional and quadratic boost converters and on the optimization of maximum power point tracking algorithms during fast changing weather conditions. These converters are modelling as switched affine systems to propose a switching rule that stabilize the operating point according to Lyapunav theory. Several simulation results using Matlab/SimulinkTM are given to declare the maximization of the extracted electrical power and the stability of the operating point. Experimental results recuperated on a test bench in the laboratory LIAS backed and confirmed the interest of the proposed approaches
Lowery, Bradley R. "Topics in communication avoiding algorithms and stability analysis." Thesis, University of Colorado at Denver, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3621837.
Повний текст джерелаHigh performance linear algebra kernels are essential for scientific computing. Fast, accurate, and robust algorithms are required to process the large amount of data present in today's applications. In this thesis, we present new performance analysis, new error analysis, new stable algorithms, and new computational results.
An algorithm's performance depends on the computational cost and the communication cost. We begin with a study of the communication cost for dense linear algebra algorithms. We improve the lower bounds for the amount of communications in matrix multiplication. We also review optimal algorithms for dense linear algebra algorithms focusing on recursive algorithms.
We also consider the communication cost of the reduction operation. A reduction is a collective communication that is often used to communicate data in a parallel application. We present two new algorithms each developed under different models. In a unidirectional model, we prove our new algorithm is optimal. In a bidirectional model, we show experimentally our new algorithm has the same time complexity of a reverse optimal broadcast. Our implementations show that the new algorithms are viable options in practice.
In the remaining chapters, we turn our attention to error analysis. We present a complete error analysis study of computing an oblique QR factorization. As part of this study we introduce a new, stable, communication avoiding algorithm. Performance experiments confirm the benefit of the communication avoiding algorithms.
Finally, we consider the error due to the balancing algorithm, a preprocessing step to the nonsymmetric eigenvalue problem. We modify the balancing algorithm by improving its stopping criteria. We present several test cases where the previous balancing algorithm deteriorated the accuracy of the computation. The new algorithm successfully maintains satisfactory backward error for all test cases.
Medina, Aguayo Felipe Javier. "Stability and examples of some approximate MCMC algorithms." Thesis, University of Warwick, 2017. http://wrap.warwick.ac.uk/88922/.
Повний текст джерелаAndréa-Novel, Brigitte d'. "Sur la commande d'une classe de systèmes mécaniques." Paris, ENMP, 1987. http://www.theses.fr/1987ENMP0067.
Повний текст джерелаZadehkhost, Sajjad. "Efficient algorithms to expedite transient stability analysis of power systems." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52816.
Повний текст джерелаApplied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
Rabbani, Ronak. "Developing and deploying enhanced algorithms to enable operational stability control systems with embedded high voltage DC links." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/12293.
Повний текст джерелаMcDonald, Dale Brian. "Feedback control algorithms through Lyapunov optimizing control and trajectory following optimization." Online access for everyone, 2006. http://www.dissertations.wsu.edu/Dissertations/Spring2006/D%5FMcDonald%5F050206.pdf.
Повний текст джерелаWan, H. B. "Voltage stability analysis using algorithmic and artificial intelligent approaches." Thesis, University of Bath, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337820.
Повний текст джерелаDiederichs, Benedikt [Verfasser], and Armin [Akademischer Betreuer] Iske. "Sparse Frequency Estimation : Stability and Algorithms / Benedikt Diederichs ; Betreuer: Armin Iske." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://d-nb.info/1175584649/34.
Повний текст джерелаDiederichs, Benedikt Verfasser], and Armin [Akademischer Betreuer] [Iske. "Sparse Frequency Estimation : Stability and Algorithms / Benedikt Diederichs ; Betreuer: Armin Iske." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://nbn-resolving.de/urn:nbn:de:gbv:18-95079.
Повний текст джерелаKalavagunta, Sushma. "Computational algorithms for stability analysis of linear systems with time-delay /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1418036.
Повний текст джерелаKandil, Nahi. "Algorithmes pour accélérer la simulation en stabilité transitoire." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0003/NQ42824.pdf.
Повний текст джерелаDosso, Mouhamadou. "Sur quelques algorithmes d'analyse de stabilité forte de matrices symplectiques." Brest, 2006. http://www.theses.fr/2006BRES2014.
Повний текст джерелаThe first chapter of this thesis presents some spectral properties of symplectic matrices and their link to the strong stability. In particular, emphasis is placed on the most numerically useful properties which are used throughout the thesis. In the second chapter we propose an adaptation of spectral dichotomy algorithms to symplectic matrices. This adaptation allows us to find, in a stable way, the spectral projections onto the invariant subspaces associated with the eigenvalues inside, on and outside the unit circle. With these information, we propose an algorithm, based again on the spectral dichotomy techniques, to analyse the strong stability. In the third chapter, we propose another approach referred to as spectral trichotomy, for computing the abovementioned spectral projections. We analyse the convergence behavior of this algorithms and compare it with the approach proposed in chapter 2
Karmakar, Saurav. "Statistical Stability and Biological Validity of Clustering Algorithms for Analyzing Microarray Data." Digital Archive @ GSU, 2005. http://digitalarchive.gsu.edu/math_theses/3.
Повний текст джерелаNoun, Nahla. "Convergence et stabilisation de systèmes dynamiques couplés et multi-échelles vers des équilibres sous contraintes : application à l’optimisation hiérarchique." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20011/document.
Повний текст джерелаWe study the convergence of dynamical systems towards equilibria. In particular, we are interested in two types of equilibria. On one hand solutions of constrained variational inequations that are also involved in the resolution of hierarchical optimization problems. On the other hand the stable state of a dynamical system, i.e. the state when the energy of the system is zero. The thesis is divided into two parts, each focused on one of these equilibria. In the first part, we study a class of forward-backward algorithms for solving constrained variational inequalities. We consider a splitting forward-backward penalty scheme. We prove the weak ergodic convergence of the algorithm to an equilibrium for a general maximal monotone operator, and the strong convergence to the unique equilibrium if the operator is an addition strongly monotone. We also apply our algorithm for solving constrained or hierarchical optimization problems whose objective and penalization functions are formed of a smooth and a non-smooth part. In fact, we show the weak convergence to a hierarchical optimum when the operator is the subdifferential of a closed convex proper function. We then generalize several known algorithms and we find their convergence results by weakening assumptions used in a number of them. In the second part, we study the action of a locally internal dissipation law in the stabilization of a linear dynamical system coupling three wave equations, the Bresse system. Under the equal speed wave propagation condition we show that the system is exponentially stable. Otherwise, when the speeds are different, we prove the polynomial stability and establish a new polynomial energy decay rate. This extends results presented in the literature in the sense that the dissipation law is locally distributed (and not applied in the whole domain) and we improve the polynomial energy decay rate with both types of boundary conditions, Dirichlet and Dirichlet-Neumann
Aronna, Maria-Soledad. "Second order analysis of optimal control problems with singular arcs : optimality conditions and shooting algorithm." Palaiseau, Ecole polytechnique, 2011. http://tel.archives-ouvertes.fr/docs/00/68/22/76/PDF/These_Aronna.pdf.
Повний текст джерелаThis thesis deals with optimal control problems for systems that are affine in one part of the control variable. First, we state necessary and sufficient second order conditions when all control variables enter linearly. We have bound control constraints and a bang-singular solution. The sufficient condition is restricted to the scalar control case. We propose a shooting algorithm and provide a sufficient condition for its local quadratic convergence. This condition guarantees the stability of the optimal solution and the local quadratic convergence of the algorithm for the perturbed problem in some cases. We present numerical tests that validate our method. Afterwards, we investigate an optimal control problems with systems that are affine in one part of the control variable. We obtain second order necessary and sufficient conditions for optimality. We propose a shooting algorithm, and we show that the sufficient condition just mentioned is also sufficient for the local quadratic convergence. Finally, we study a model of optimal hydrothermal scheduling. We investigate, by means of necessary conditions due to Goh, the possible occurrence of a singular arc
Eskenazi, Sébastien. "On the stability of document analysis algorithms : application to hybrid document hashing technologies." Thesis, La Rochelle, 2016. http://www.theses.fr/2016LAROS019/document.
Повний текст джерелаAn innumerable number of documents is being printed, scanned, faxed, photographed every day. These documents are hybrid : they exist as both hard copies and digital copies. Moreover their digital copies can be viewed and modified simultaneously in many places. With the availability of image modification software, it has become very easy to modify or forge a document. This creates a rising need for an authentication scheme capable of handling these hybrid documents. Current solutions rely on separate authentication schemes for paper and digital documents. Other solutions rely on manual visual verification and offer only partial security or require that sensitive documents be stored outside the company’s premises and a network access at the verification time. In order to overcome all these issues we propose to create a semantic hashing algorithm for document images. This hashing algorithm should provide a compact digest for all the visually significant information contained in the document. This digest will allow current hybrid security systems to secure all the document. This can be achieved thanks to document analysis algorithms. However those need to be brought to an unprecedented level of performance, in particular for their reliability which depends on their stability. After defining the context of this study and what is a stable algorithm, we focused on producing stable algorithms for layout description, document segmentation, character recognition and describing the graphical parts of a document