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Gupta, Sujasha. "Development and Utilization of a Novel Synaptic Transistor to Detect Dynamic Neuronal Processes." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1590765716831174.
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Zang, Peng. "Scaling solutions to Markov Decision Problems." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42906.
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The Markov Decision Problem (MDP) is a widely applied mathematical model useful for describing a wide array of real world decision problems ranging from navigation to scheduling to robotics. Existing methods for solving MDPs scale poorly when applied to large domains where there are many components and factors to consider.
In this dissertation, I study the use of non-tabular representations and human input as scaling techniques. I will show that the joint approach has desirable optimality and convergence guarantees, and demonstrates several orders of magnitude speedup over conventional tabular methods. Empirical studies of speedup were performed using several domains including a clone of the classic video game, Super Mario Bros. In the course of this work, I will address several issues including: how approximate representations can be used without losing convergence and optimality properties, how human input can be solicited to maximize speedup and user engagement, and how that input should be used so as to insulate against possible errors.
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Deb, Abhishek. "HW/SW mechanisms for instruction fusion, issue and commit in modern u-processors." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/81561.
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In this thesis we have explored the co-designed paradigm to show alternative processor design points. Specifically, we have provided HW/SW mechanisms for instruction fusion, issue and commit for modern processors. We have implemented a co-designed virtual machine monitor that binary translates x86 instructions into RISC like micro-ops. Moreover, the translations are stored as superblocks, which are a trace of basic blocks. These superblocks are further optimized using speculative and non-speculative optimizations. Hardware mechanisms exists in-order to take corrective action in case of misspeculations. During the course of this PhD we have made following contributions.
Firstly, we have provided a novel Programmable Functional unit, in-order to speed up general-purpose applications. The PFU consists of a grid of functional units, similar to CCA, and a distributed internal register file. The inputs of the macro-op are brought from the Physical Register File to the internal register file using a set of moves and a set of loads. A macro-op fusion algorithm fuses micro-ops at runtime. The fusion algorithm is based on a scheduling step that indicates whether the current fused instruction is beneficial or not. The micro-ops corresponding to the macro-ops are stored as control signals in a configuration. The macro-op consists of a configuration ID which helps in locating the configurations. A small configuration cache is present inside the Programmable Functional unit, that holds these configurations. In case of a miss in the configuration cache configurations are loaded from I-Cache. Moreover, in-order to support bulk commit of atomic superblocks that are larger
than the ROB we have proposed a speculative commit mechanism. For this we have proposed a Speculative commit register map table that holds the mappings of the speculatively committed instructions. When all the instructions of the superblock have committed the speculative state is copied to Backend Register Rename Table.
Secondly, we proposed a co-designed in-order processor with with two kinds of accelerators. These FU based accelerators run a pair of fused instructions. We have considered two kinds of instruction fusion. First, we fused a pair of independent loads together into vector loads and execute them on vector load units. For the second kind of instruction fusion we have fused a pair of dependent simple ALU instructions and execute them in Interlock Collapsing ALUs (ICALU). Moreover, we have evaluated performance of various code optimizations such as list-scheduling, load-store telescoping and load hoisting among others. We have compared our co-designed processor with small instruction window out-of-order processors.
Thirdly, we have proposed a co-designed out-of-order processor. Specifically we have reduced complexity in two areas. First
of all, we have co-designed the commit mechanism, that enable bulk commit of atomic superblocks. In this solution we got rid of the conventional ROB, instead we introduce the Superblock Ordering Buffer (SOB). SOB ensures program order is maintained at the granularity of the superblock, by bulk committing the program state. The program state consists of the register state and the memory state. The register state is held in a per superblock register map table, whereas the memory state is held in gated store buffer and updated in bulk. Furthermore, we have tackled the complexity of Out-of-Order issue logic by using FIFOs. We have proposed an enhanced steering heuristic that fixes the inefficiencies of the existing dependence-based heuristic. Moreover, a mechanism to release the FIFO entries earlier is also proposed that further improves the performance of the steering heuristic.En aquesta tesis hem explorat el paradigma de les màquines issue i commit per processadors actuals. Hem implementat una màquina virtual que tradueix binaris x86 a micro-ops de tipus RISC. Aquestes traduccions es guarden com a superblocks, que en realitat no és més que una traça de virtuals co-dissenyades. En particular, hem proposat mecanismes hw/sw per a la fusió d’instruccions, blocs bàsics. Aquests superblocks s’optimitzen utilitzant optimizacions especualtives i d’altres no speculatives. En cas de les optimizations especulatives es consideren mecanismes per a la gestió de errades en l’especulació. Al llarg d’aquesta tesis s’han fet les següents contribucions: Primer, hem proposat una nova unitat functional programmable (PFU) per tal de millorar l’execució d’aplicacions de proposit general. La PFU està formada per un conjunt d’unitats funcionals, similar al CCA, amb un banc de registres intern a la PFU distribuït a les unitats funcionals que la composen. Les entrades de la macro-operació que s’executa en la PFU es mouen del banc de registres físic convencional al intern fent servir un conjunt de moves i loads. Un algorisme de fusió combina més micro-operacions en temps d’execució. Aquest algorisme es basa en un pas de planificació que mesura el benefici de les decisions de fusió. Les micro operacions corresponents a la macro operació s’emmagatzemen com a senyals de control en una configuració. Les macro-operacions tenen associat un identificador de configuració que ajuda a localitzar d’aquestes. Una petita cache de configuracions està present dintre de la PFU per tal de guardar-les. En cas de que la configuració no estigui a la cache, les configuracions es carreguen de la cache d’instruccions. Per altre banda, per tal de donar support al commit atòmic dels superblocks que sobrepassen el tamany del ROB s’ha proposat un mecanisme de commit especulatiu. Per aquest mecanisme hem proposat una taula de mapeig especulativa dels registres, que es copia a la taula no especulativa quan totes les instruccions del superblock han comitejat. Segon, hem proposat un processador en order co-dissenyat que combina dos tipus d’acceleradors. Aquests acceleradors executen un parell d’instruccions fusionades. S’han considerat dos tipus de fusió d’instructions. Primer, combinem un parell de loads independents formant loads vectorials i els executem en una unitat vectorial. Segon, fusionem parells d’instruccions simples d’alu que són dependents i que s’executaran en una Interlock Collapsing ALU (ICALU). Per altra aquestes tecniques les hem evaluat conjuntament amb diverses optimizacions com list scheduling, load-store telescoping i hoisting de loads, entre d’altres. Aquesta proposta ha estat comparada amb un processador fora d’ordre. Tercer, hem proposat un processador fora d’ordre co-dissenyat efficient reduint-ne la complexitat en dos areas principals. En primer lloc, hem co-disenyat el mecanisme de commit per tal de permetre un eficient commit atòmic del superblocks. En aquesta solució hem substituït el ROB convencional, i en lloc hem introduït el Superblock Ordering Buffer (SOB). El SOB manté l’odre de programa a granularitat de superblock. L’estat del programa consisteix en registres i memòria. L’estat dels registres es manté en una taula per superblock, mentre que l’estat de memòria es guarda en un buffer i s’actulitza atòmicament. La segona gran area de reducció de complexitat considerarada és l’ús de FIFOs a la lògica d’issue. En aquest últim àmbit hem proposat una heurística de distribució que solventa les ineficiències de l’heurística basada en dependències anteriorment proposada. Finalment, i junt amb les FIFOs, s’ha proposat un mecanisme per alliberar les entrades de la FIFO anticipadament.
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Ковальов, Сергій Федорович, Сергей Федорович Ковалев, Serhii Fedorovych Kovalov, Михайло Сергійович Овчаренко, Михаил Сергеевич Овчаренко, Mykhailo Serhiiovych Ovcharenko, Андрій Анатолійович Папченко, Андрей Анатольевич Папченко, Andrii Anatoliiovych Papchenko, and Ю. О. Видиш. "Розроблення та дослідження роторно-динамічного агрегата-гомогенізатора для технології виробництва згущеного молока." Thesis, Сумський державний університет, 2016. http://essuir.sumdu.edu.ua/handle/123456789/45621.
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В даний час через підвищення цін на енергоносії та сировину особливо
гостро постало завдання створення технологічного обладнання з низькими
питомими енерговитратами на проведення різних технологічних процесів і
одночасним підвищенням якості виробленої продукції. До такого
устаткування в повній мірі можна віднести роторно-динамічні агрегати-
гомогенізатори.
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Hall, Otto. "Inference of buffer queue times in data processing systems using Gaussian Processes : An introduction to latency prediction for dynamic software optimization in high-end trading systems." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214791.
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This study investigates whether Gaussian Process Regression can be applied to evaluate buffer queue times in large scale data processing systems. It is additionally considered whether high-frequency data stream rates can be generalized into a small subset of the sample space. With the aim of providing basis for dynamic software optimization, a promising foundation for continued research is introduced. The study is intended to contribute to Direct Market Access financial trading systems which processes immense amounts of market data daily. Due to certain limitations, we shoulder a naïve approach and model latencies as a function of only data throughput in eight small historical intervals. The training and test sets are represented from raw market data, and we resort to pruning operations to shrink the datasets by a factor of approximately 0.0005 in order to achieve computational feasibility. We further consider four different implementations of Gaussian Process Regression. The resulting algorithms perform well on pruned datasets, with an average R2 statistic of 0.8399 over six test sets of approximately equal size as the training set. Testing on non-pruned datasets indicate shortcomings from the generalization procedure, where input vectors corresponding to low-latency target values are associated with less accuracy. We conclude that depending on application, the shortcomings may be make the model intractable. However for the purposes of this study it is found that buffer queue times can indeed be modelled by regression algorithms. We discuss several methods for improvements, both in regards to pruning procedures and Gaussian Processes, and open up for promising continued research.Denna studie undersöker huruvida Gaussian Process Regression kan appliceras för att utvärdera buffer-kötider i storskaliga dataprocesseringssystem. Dessutom utforskas ifall dataströmsfrekvenser kan generaliseras till en liten delmängd av utfallsrymden. Medmålet att erhålla en grund för dynamisk mjukvaruoptimering introduceras en lovandestartpunkt för fortsatt forskning. Studien riktas mot Direct Market Access system för handel på finansiella marknader, somprocesserar enorma mängder marknadsdata dagligen. På grund av vissa begränsningar axlas ett naivt tillvägagångssätt och väntetider modelleras som en funktion av enbartdatagenomströmning i åtta små historiska tidsinterval. Tränings- och testdataset representeras från ren marknadsdata och pruning-tekniker används för att krympa dataseten med en ungefärlig faktor om 0.0005, för att uppnå beräkningsmässig genomförbarhet. Vidare tas fyra olika implementationer av Gaussian Process Regression i beaktning. De resulterande algorithmerna presterar bra på krympta dataset, med en medel R2 statisticpå 0.8399 över sex testdataset, alla av ungefär samma storlek som träningsdatasetet. Tester på icke krympta dataset indikerar vissa brister från pruning, där input vektorermotsvararande låga latenstider är associerade med mindre exakthet. Slutsatsen dras att beroende på applikation kan dessa brister göra modellen obrukbar. För studiens syftefinnes emellertid att latenstider kan sannerligen modelleras av regressionsalgoritmer. Slutligen diskuteras metoder för förbättrning med hänsyn till både pruning och GaussianProcess Regression, och det öppnas upp för lovande vidare forskning.
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Костенко, Юрий Викторович. "Анализ параметров динамических процессов в виброударных машинах с изменяющимися массово-жесткостными характеристиками." Thesis, НТУ "ХПИ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19912.
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Диссертация на соискание научной степени кандидата технических наук по специальности 05.02.09 – динамика и прочность машин. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2016.
Диссертация посвящена разработке подходов, методов и моделей для исследования динамических процессов в виброударных системах с учетом изменяемой во времени массы технологического груза и нелинейной жесткости упругих опор. В данной работе изложен новый подход к учету влияния переменной массы технологического груза на характер динамических процессов в виброударной системе. Разработаны и предложены зависимости, математические модели, которые описывают характер изменения массы технологического груза во времени, как на основе экспериментальных исследований (эмпирический закон), так и в зависимости от количества диссипированной энергии. Установлено, что вследствии нелинейности жесткости упругих опор и в зависимости от их конструктивного исполнения, становится возможной реализация субгармонических режимов, что приводит к росту силы ударного взаимодействия. Для оценки влияния параметров упругих опор (варианты конструктивного исполнения, жесткость пружин) проведены многовариантные исследования, по результатам которых выделены характерные субгармонические режимы и их характеристики (фазовые портреты, временные распределения). Установлена степень влияния изменения различных параметров упругих опор на характер колебательного процесса в ходе их многовариантного варьирования. На базе корпуса усовершенствованной вибромашины, функционирующей в составе автоматизированной линии для выбивки крупного вагонного литья, проведен натурный эксперимент с целью подтверждения точности и адекватности полученных ранее результатов численных исследований.The thesis on competition of a scientific degree of Candidate of technical Science on a specialty 05.02.09 – dynamic and strength of machines. – National Technical University "Kharkiv polytechnical institute", Kharkiv, 2016. This thesis is devoted to the development of approaches, methods and models for investigation of dynamic processes in vibroimpact systems with variable mass of the weight and nonlinear rigidness of elastic supports. In this paper new approach to the accounting of the variable mass influence on the character of dynamical processes in vibroimpact systems was presented. The dependences, that describes the mass change character, based on experimental researches and dependence from dissipated energy were proposed. It was found that the realization of sybharmonical modes became possible because of elastic supports nonlinearity and design features. The realization of subharmonical modes lead to growth of impact interaction force. The approach, based on corresponding values for phase variables at the beginning and the end of period was proposed to periodic solutions search. The criteria for tuning from resonance frequencies that can appear on perturbing force with multiple (partite) frequency were formulated. The machine body designed with taking to the account previously formulated recommen-dations was created. The investigation of stress-strain status was performed and found that improved machine body satisfies strength requirements. The comparison of numerical and experimental data was done. The accuracy and authenticity of numerical investigations was confirmed.
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Костенко, Юрій Вікторович. "Аналіз параметрів динамічних процесів у віброударних машинах зі змінними масово-жорсткісними характеристиками." Thesis, ФО-П Дуюнова Т. В, 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19909.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.02.09 – динаміка та міцність машин. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016.
Дисертація присвячена розробці підходів, методів і моделей для дослідження динамічних процесів у віброударних системах з урахуванням змінної у часі маси технологічного вантажу та нелінійної жорсткості пружних опор. У роботі викладений новий підхід до урахування впливу змінної маси технологічного вантажу на характер динамічних процесів у віброударній системі. Запропоновані залежності, що описують характер зміни маси як на основі експериментальних досліджень, так і залежно від дисипації енергії при ударі. Встановлено, що внаслідок нелінійної жорсткості пружних опор та залежно від їх конструктивного виконання, можливою є реалізація субгармонійних режимів, що призводить до зростання сили ударної взаємодії. Для пошуку періодичних розв'язків був запропонований новий підхід, що базується на відповідності фазових змінних на початку та в кінці періоду процесу. На основі результатів досліджень сформульовані критерії для відлаштування від резонансу, що може виникнути на кратних (дольних) частотах збудження. З урахування рекомендацій створена удосконалена конструкція корпусу віброударної машини. Проведені дослідження напружено-деформованого стану удосконаленого корпусу вібромашини та встановлено, що він відповідає вимогам міцності. Проведене порівняння отриманих числових результатів досліджень з експериментальними даними. Підтверджена точність і достовірність проведених числових досліджень.The thesis on competition of a scientific degree of Candidate of technical Science on a specialty 05.02.09 – dynamic and strength of machines. – National Technical University "Kharkiv polytechnical institute", Kharkiv, 2016. This thesis is devoted to the development of approaches, methods and models for investigation of dynamic processes in vibroimpact systems with variable mass of the weight and nonlinear rigidness of elastic supports. In this paper new approach to the accounting of the variable mass influence on the character of dynamical processes in vibroimpact systems was presented. The dependences, that describes the mass change character, based on experimental researches and dependence from dissipated energy were proposed. It was found that the realization of sybharmonical modes became possible because of elastic supports nonlinearity and design features. The realization of subharmonical modes lead to growth of impact interaction force. The approach, based on corresponding values for phase variables at the beginning and the end of period was proposed to periodic solutions search. The criteria for tuning from resonance frequencies that can appear on perturbing force with multiple (partite) frequency were formulated. The machine body designed with taking to the account previously formulated recommen-dations was created. The investigation of stress-strain status was performed and found that improved machine body satisfies strength requirements. The comparison of numerical and experimental data was done. The accuracy and authenticity of numerical investigations was confirmed.
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Hakala, Tim. "Settling-Time Improvements in Positioning Machines Subject to Nonlinear Friction Using Adaptive Impulse Control." BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/1061.
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A new method of adaptive impulse control is developed to precisely and quickly control the position of machine components subject to friction. Friction dominates the forces affecting fine positioning dynamics. Friction can depend on payload, velocity, step size, path, initial position, temperature, and other variables. Control problems such as steady-state error and limit cycles often arise when applying conventional control techniques to the position control problem. Studies in the last few decades have shown that impulsive control can produce repeatable displacements as small as ten nanometers without limit cycles or steady-state error in machines subject to dry sliding friction. These displacements are achieved through the application of short duration, high intensity pulses. The relationship between pulse duration and displacement is seldom a simple function. The most dependable practical methods for control are self-tuning; they learn from online experience by adapting an internal control parameter until precise position control is achieved. To date, the best known adaptive pulse control methods adapt a single control parameter. While effective, the single parameter methods suffer from sub-optimal settling times and poor parameter convergence. To improve performance while maintaining the capacity for ultimate precision, a new control method referred to as Adaptive Impulse Control (AIC) has been developed. To better fit the nonlinear relationship between pulses and displacements, AIC adaptively tunes a set of parameters. Each parameter affects a different range of displacements. Online updates depend on the residual control error following each pulse, an estimate of pulse sensitivity, and a learning gain. After an update is calculated, it is distributed among the parameters that were used to calculate the most recent pulse. As the stored relationship converges to the actual relationship of the machine, pulses become more accurate and fewer pulses are needed to reach each desired destination. When fewer pulses are needed, settling time improves and efficiency increases. AIC is experimentally compared to conventional PID control and other adaptive pulse control methods on a rotary system with a position measurement resolution of 16000 encoder counts per revolution of the load wheel. The friction in the test system is nonlinear and irregular with a position dependent break-away torque that varies by a factor of more than 1.8 to 1. AIC is shown to improve settling times by as much as a factor of two when compared to other adaptive pulse control methods while maintaining precise control tolerances.
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Cupertino, Thiago Henrique. "Machine learning via dynamical processes on complex networks." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-25032014-154520/.
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Extracting useful knowledge from data sets is a key concept in modern information systems. Consequently, the need of efficient techniques to extract the desired knowledge has been growing over time. Machine learning is a research field dedicated to the development of techniques capable of enabling a machine to \"learn\" from data. Many techniques have been proposed so far, but there are still issues to be unveiled specially in interdisciplinary research. In this thesis, we explore the advantages of network data representation to develop machine learning techniques based on dynamical processes on networks. The network representation unifies the structure, dynamics and functions of the system it represents, and thus is capable of capturing the spatial, topological and functional relations of the data sets under analysis. We develop network-based techniques for the three machine learning paradigms: supervised, semi-supervised and unsupervised. The random walk dynamical process is used to characterize the access of unlabeled data to data classes, configuring a new heuristic we call ease of access in the supervised paradigm. We also propose a classification technique which combines the high-level view of the data, via network topological characterization, and the low-level relations, via similarity measures, in a general framework. Still in the supervised setting, the modularity and Katz centrality network measures are applied to classify multiple observation sets, and an evolving network construction method is applied to the dimensionality reduction problem. The semi-supervised paradigm is covered by extending the ease of access heuristic to the cases in which just a few labeled data samples and many unlabeled samples are available. A semi-supervised technique based on interacting forces is also proposed, for which we provide parameter heuristics and stability analysis via a Lyapunov function. Finally, an unsupervised network-based technique uses the concepts of pinning control and consensus time from dynamical processes to derive a similarity measure used to cluster data. The data is represented by a connected and sparse network in which nodes are dynamical elements. Simulations on benchmark data sets and comparisons to well-known machine learning techniques are provided for all proposed techniques. Advantages of network data representation and dynamical processes for machine learning are highlighted in all casesA extração de conhecimento útil a partir de conjuntos de dados é um conceito chave em sistemas de informação modernos. Por conseguinte, a necessidade de técnicas eficientes para extrair o conhecimento desejado vem crescendo ao longo do tempo. Aprendizado de máquina é uma área de pesquisa dedicada ao desenvolvimento de técnicas capazes de permitir que uma máquina \"aprenda\" a partir de conjuntos de dados. Muitas técnicas já foram propostas, mas ainda há questões a serem reveladas especialmente em pesquisas interdisciplinares. Nesta tese, exploramos as vantagens da representação de dados em rede para desenvolver técnicas de aprendizado de máquina baseadas em processos dinâmicos em redes. A representação em rede unifica a estrutura, a dinâmica e as funções do sistema representado e, portanto, é capaz de capturar as relações espaciais, topológicas e funcionais dos conjuntos de dados sob análise. Desenvolvemos técnicas baseadas em rede para os três paradigmas de aprendizado de máquina: supervisionado, semissupervisionado e não supervisionado. O processo dinâmico de passeio aleatório é utilizado para caracterizar o acesso de dados não rotulados às classes de dados configurando uma nova heurística no paradigma supervisionado, a qual chamamos de facilidade de acesso. Também propomos uma técnica de classificação de dados que combina a visão de alto nível dos dados, por meio da caracterização topológica de rede, com relações de baixo nível, por meio de medidas de similaridade, em uma estrutura geral. Ainda no aprendizado supervisionado, as medidas de rede modularidade e centralidade Katz são aplicadas para classificar conjuntos de múltiplas observações, e um método de construção evolutiva de rede é aplicado ao problema de redução de dimensionalidade. O paradigma semissupervisionado é abordado por meio da extensão da heurística de facilidade de acesso para os casos em que apenas algumas amostras de dados rotuladas e muitas amostras não rotuladas estão disponíveis. É também proposta uma técnica semissupervisionada baseada em forças de interação, para a qual fornecemos heurísticas para selecionar parâmetros e uma análise de estabilidade mediante uma função de Lyapunov. Finalmente, uma técnica não supervisionada baseada em rede utiliza os conceitos de controle pontual e tempo de consenso de processos dinâmicos para derivar uma medida de similaridade usada para agrupar dados. Os dados são representados por uma rede conectada e esparsa na qual os vértices são elementos dinâmicos. Simulações com dados de referência e comparações com técnicas de aprendizado de máquina conhecidas são fornecidos para todas as técnicas propostas. As vantagens da representação de dados em rede e de processos dinâmicos para o aprendizado de máquina são evidenciadas em todos os casos
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Göl, Özdemir. "Dynamic modelling of induction machines /." Title page, contents and abstract only, 1993. http://web4.library.adelaide.edu.au/theses/09PH/09phg595.pdf.
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Walton, Christopher D. "Abstract machines for dynamic computation." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/372.
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In this thesis we address the challenges associated with the provision of dynamic software architectures. These are systems in which programs are constructed from separately compiled units with a facility for the replacement of these units at runtime. Typical examples of applications which will benefit from this dynamic approach are long-lived systems in which downtime is highly undesirable, for example, web-servers, database engines, and equipment controllers. In addition, dynamic software architectures are also gaining popularity with the recent advent of wide-area Internet applications, where it is often impractical to compile a program in its entirety or begin execution in a single step. Our approach to dynamic software architectures differs from earlier attempts in that we guarantee the safety of the replacement operation. This is done by founding our techniques on the rigour of strong typing. In the first half of the thesis we take an existing static software architecture with strong typing facilities and modular program construction, namely the Standard ML platform, and equip it with facilities for separate-compilation and code-replacement of modules. The resulting dynamic software architecture, which we call Dynamic ML, ensures the safety of replacement through an effective use of state-of-the-art advances in the fields of types in compilation and abstract machines. In the latter half of the thesis we extend Dynamic ML with a facility for distributed execution and adapt our code-replacement model accordingly. This will permit the construction of larger dynamic architectures, for example, across a distributed network of workstations. We also perform a mechanical verification of the distributed algorithm by model checking, to gain further confidence in the correctness of our approach. At the end of the thesis we outline an implementation of our techniques for the Java language, demonstrating the portability of our approach.
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Успенський, Борис Валерійович. "Нелінійні нормальні форми коливань силових передач двигунів внутрішнього згоряння." Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/24074.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю05.02.09 – динаміка та міцність мащин. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016. Дисертацію присвячено розробці методів розрахунку нелінійних нормальних форм механічних систем, що моделюють крутильні коливання силових передач двигунів внутрішнього згоряння. В роботі запропоновано ряд чисельних та чисельно-аналітичних методів, що дозволяють знаходити нелінійні нормальні форми кусково-лінійних систем, які моделюють окремі ланки силових передач. В роботі запропоновано модифікацію методу нелінійних нормальних форм Шоу-П'єра, яка дозволила значно підвищити швидкодію та точність методу. Розроблена методика форм Шоу-П’єра разом із модифікованим методом Раушера дозволила знаходити нелінійні нормальні форми Шоу-П'єра вимушених коливань кусково-лінійних систем. Розроблено чисельні методи пошуку нелінійних нормальних форм Каудерера-Розенберга вільних та вимушених коливань кусково-лінійних систем. Знайдено нелінійні нормальні форми Шоу-П'єра вільних коливань силової передачі дизельного двигуна 3ТД-4 та зроблено висновки щодо характеру коливань силової передачі в резонансних та нерезонансних областях.The thesis in qualification for a scientific degree of Candidate of Technical Science in specialty 05.02.09 – dynamicsand strength of machines, National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2016. The thesis is devoted to development of approaches and methods for analysis of nonlinear normal modes of torsion vibrationsin power transmissions. In the work a variety of both numerical and semi numerical methods of calculating nonlinear normal modes in piecewise linear systems is introduced. Numerical methods for calculating the Kauderer-Rosenberg normal modes in piecewise linear systems can be used for analysis of small number-of-degrees systems with strong piecewise linear nonlinearity, both free and under harmonic excitation. Semi numerical methods for obtaining Shaw-Pierre nonlinear normal modes in piecewise linear systems are introduced. The basis Shaw-Pierre NNM technique is modified for better precision and speed. Developed modifications allowed analyzing a 15-degrees-of-freedom model of torsion vibrations in power transmission of a diesel. High efficiency and precision of the modified Shaw-Pierre NNMs technique allows its using for parametrical and structural synthesis of power transmissions.
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Успенский, Борис Валерьевич. "Нелинейные нормальные формы колебаний силовых передач двигателей внутреннего сгорания." Thesis, НТУ "ХПИ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/24077.
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Диссертация на соискание учёной степени кандидата технических наук по специальности 05.02.09 – динамика и прочность машин. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2016. Диссертация посвящена разработке методов расчёта нелинейных нормальных форм механических систем, моделирующих крутильные колебаний силовых передач двигателей внутреннего сгорания. В работе предложен ряд численных и численно-аналитических методов, позволяющих находить нелинейные нормальные формы кусочно-линейных систем, моделирующих отдельные звенья силовых передач. Предложена модификация метода нелинейных нормальных форм Шоу-Пьера, которая позволяет значительно увеличить быстродействие и точность этого метода. Благодаря разработанной методике анализа кусочно-линейных систем появилась возможность расчёта нелинейных нормальных форм Шоу-Пьера в системах с большим числом степеней свободы и кусочно-линейными упругими характеристиками. Это позволило решить задачу расчёта нелинейных колебаний реальных моделей силовых передач, в частности, силовой передачи двигателя 3ТД-4. Метод форм Шоу-Пьера продемонстрировал высокую точность и эффективность, что подтверждается сравнением с результатами численного интегрирования дифференциальных уравнений крутильных колебаний силовых передач. Разработанная методика поиска форм Шоу-Пьера в сочетании с модифицированным методом Раушера позволила находить нелинейные нормальные формы Шоу-Пьера вынужденных колебаний кусочно-линейных систем. Численный анализ установившихся колебаний силовых передач под действием периодического внешнего крутящего момента позволяет утверждать, что в резонансных областях движения происходят по нелинейным нормальным формам. При этом диссипация практически не влияет на вид нелинейных нормальных форм. Расчёт нелинейных нормальных форм Шоу-Пьера свободных колебаний силовой передачи дизельного двигателя 3ТД-4 позволил сделать выводы о параметрах динамической прочности передачи.The thesis in qualification for a scientific degree of Candidate of Technical Science in specialty 05.02.09 – dynamicsand strength of machines, National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2016. The thesis is devoted to development of approaches and methods for analysis of nonlinear normal modes of torsion vibrationsin power transmissions. In the work a variety of both numerical and semi numerical methods of calculating nonlinear normal modes in piecewise linear systems is introduced. Numerical methods for calculating the Kauderer-Rosenberg normal modes in piecewise linear systems can be used for analysis of small number-of-degrees systems with strong piecewise linear nonlinearity, both free and under harmonic excitation. Semi numerical methods for obtaining Shaw-Pierre nonlinear normal modes in piecewise linear systems are introduced. The basis Shaw-Pierre NNM technique is modified for better precision and speed. Developed modifications allowed analyzing a 15-degrees-of-freedom model of torsion vibrations in power transmission of a diesel. High efficiency and precision of the modified Shaw-Pierre NNMs technique allows its using for parametrical and structural synthesis of power transmissions.
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Sutherland, Graham Stuart. "Photon desorption processes in large research machines." Thesis, University of Liverpool, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386844.
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Singh, Bhupender. "Dynamic Organization of Molecular Machines in Bacteria." Doctoral thesis, Uppsala universitet, Institutionen för cell- och molekylärbiologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-157691.
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Bacterial cells were once treated as membrane-enclosed bags of cytoplasm: a homogeneous, undifferentiated suspension in which polymers (proteins, nucleic acids, etc.) and small molecules diffused freely to interact with each other. Biochemical studies have determined the molecular mechanisms underlying the biological processes of metabolism, replication and transcription-translation, etc. However, recent advancements in optical techniques armed with fluorescent tags for proteins and nucleic acids have increased our ability to peer into the interior of live bacterial cells. This has revealed an organized layout of multi-protein complexes, or molecular machines, dedicated to specific functions at defined sub-cellular locations; the timing of their assembly and/or rates of their activity being determined by available nutrition and environmental signals from the niche occupied by the organism. In the present study, we have attempted to identify the intracellular location and organization of the molecular machines assembled for protein synthesis (ribosomes), DNA replication (replisomes) and cell division (divisome) in different bacteria. We have used the model system Escherichia coli as well as Helicobacter pylori and mycobacterial strains (Mycobacterium marinum and Mycobacterium smegmatis), which grow at different rates and move to dormancy late into stationary phase Bacterial nucleoid plays a major role in organizing the location and movement of active ribosomes, replisomes and placement of divisome. While the active ribosomes appear to follow the dynamic folds of the bacterial nucleoid during cell growth in E. coli, inactive ribosomes appear to accumulate near the periphery. The replisome in H. pylori was visualized as a sharp, single focus upon SSB and DnaB co-localization in growing helical rods but disassembled into diffused fluorescence when the cells attained non-replicative coccoid stage. Our investigation into mycobacterial life-cycle revealed unique features such as an absence of a dedicated mid-cell site for divisome assembly and endosporulation upon entry into stationary phase. In brief, we present the cell cycle-dependent subcellular organization of molecular machines in bacteria.
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Dalcher, Darren. "Investigating dynamic software processes." Thesis, King's College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252083.
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McGregor, Juliette Elizabeth. "Imaging dynamic biological processes." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609205.
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Bubic, F. R. (Frank Ranko). "Dynamic modelling, design and control of biorobotic machines." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37699.
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An original way to define, analyze and design mechanical systems with inherently lifelike dynamic properties is presented. The construction of robotic manipulators which embody a complete set of technologically relevant biological principles is outlined. The ultimate objective is to develop a new class of mobile, autonomous, and interactive machines which dynamically emulate live musculoskeletal systems.This study introduces the mathematical models and algorithms to transform and synthesize the results of research in musculoskeletal physiology into explicit engineering design specifications. The application of a new contractile muscle-like viscoelastic motor, as a servomechanical drive for articulated rigid link mechanisms as well as for a novel flexible trunk-like manipulator, is investigated. Key features of the neuromuscular force control by twitch summation are combined to formulate a pulse stream control method suitable for fluid powered mechanisms.
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Qin, Yong. "Dynamic modelling of combustion processes." Thesis, Cardiff University, 2007. http://orca.cf.ac.uk/55453/.
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Neural aided combustion oscillator models (NACO) have been developed for time domain prediction of low frequency oscillations. The NACO method consists of two stages, one is the design of a core-stimulation (CS) model based on the co.
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Smith, G. J. "Dynamic simulation of chemical processes." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372635.
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Ruiz, Olles Jorge. "Dynamic processes in supramolecular gels." Thesis, University of York, 2017. http://etheses.whiterose.ac.uk/20429/.
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Supramolecular gels are self-assembled solid-like materials with a large solvent component making up a liquid-like phase. The 3D scaffold, which is self-assembled from low-molecular-weight building blocks, and is present in form of nanostructured fibres, holds the mobile liquid phase, preventing bulk flow. As a consequence, these gels have interesting dynamic properties, which were the subject of study in this thesis. Chapter One provides an introduction to dynamic processes in gels. Chapter Two focusses on the thermodynamics and kinetics of a two-component gelator system based on a peptide dendron acid combined with an amine. We used rheology, CD spectroscopy and NMR to characterise the gelation process at different length scales (macroscopic, nanoscale and molecular scale respectively). We conclude that thermodynamic stability of the gel network does not correlate with the rate of network formation. Chapter Three reports diffusion across a gel-gel interface, comparing the diffusion of self-assembling small molecules with those which do not form gel fibres. Chapter Four reports the gelation capabilities of certain gelator in deep eutectic solvents. We monitor the ionic conductivity and demonstrate that conductivities for the deep eutectic gels are similar to those of the deep eutectic liquids themselves, indicating that the ionic components do not suffer from immobilisation through interaction with the self-assembled gel nanofibres. Chapter five reports all Experimental details, materials and methods. In summary, this thesis provides insights into a range of different dynamic processes in gels – (i) the formation of gels, (ii) the mobility of the solid-like fibres themselves, and (iii) the mobility/conductivity of ionic species in innovative deep eutectic gels.
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Singh, Lakhbinder. "Dynamic simulation of chemical processes." Thesis, Aston University, 1991. http://publications.aston.ac.uk/9731/.
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This thesis describes the design and implementation of an interactive dynamic simulator called DASPRII. The starting point of this research has been an existing dynamic simulation package, DASP. DASPII is written in standard FORTRAN 77 and is implemented on universally available IBM-PC or compatible machines. It provides a means for the analysis and design of chemical processes. Industrial interest in dynamic simulation has increased due to the recent increase in concern over plant operability, resiliency and safety. DASPII is an equation oriented simulation package which allows solution of dynamic and steady state equations. The steady state can be used to initialise the dynamic simulation. A robust non linear algebraic equation solver has been implemented for steady state solution. This has increased the general robustness of DASPII, compared to DASP. A graphical front end is used to generate the process flowsheet topology from a user constructed diagram of the process. A conversational interface is used to interrogate the user with the aid of a database, to complete the topological information. An original modelling strategy implemented in DASPII provides a simple mechanism for parameter switching which creates a more flexible simulation environment. The problem description generated is by a further conversational procedure using a data-base. The model format used allows the same model equations to be used for dynamic and steady state solution. All the useful features of DASPI are retained in DASPII. The program has been demonstrated and verified using a number of example problems, Significant improvements using the new NLAE solver have been shown. Topics requiring further research are described. The benefits of variable switching in models has been demonstrated with a literature problem.
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Bai, Shuanghua. "Data reconciliation for dynamic processes." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/29279.
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In a modern chemical plant, the implementation of a distributed control system leads to a large number of measurements that are available online for process monitoring, control, optimization and management decision making. Unfortunately, these measurements often contain errors that degrade the information quality obtained from the raw data. This thesis is dedicated to the development of dynamic data reconciliation (DDR) algorithms for the optimal estimation of variables in dynamic processes. More importantly, the DDR algorithms were implemented within the structures of feedback control loops, and the performance of the DDR algorithms as well as the controllers was quantitatively assessed via a series of process simulations. The DDR algorithms, acting as digital filters, were compared to commonly used filters, such as the exponentially weighted moving average (EWMA), moving average (MA), Kalman and extended Kalman filters. Methodologies to use the DDR algorithms to deal with autocorrelated noise were also investigated.
The DDR algorithms integrate information from both measurements and process dynamic models such that, at each sampling time, the estimates obtained by the DDR algorithms provide more precise representations of the current state of the process. Three DDR algorithms were developed, namely, nonlinear programming (NLP) based DDR, predictor-corrector based DDR, and autoassociative neural network (AANN) based DDR.
Evaluations of these DDR algorithms were conducted via simulations of three chemical processes, namely a cylindrical storage tank, a spherical storage tank and a binary distillation column. Results demonstrated that the DDR algorithms are efficient and effective tools for the estimation of dynamic processes. They perform significantly better than the EWMA and MA filters. Furthermore, compared to the Kalman filter, the DDR algorithm is easier to understand and to implement. Studies also showed that the structure of process models has considerable impact on the performance of the DDR. The use of the DDR algorithms embedded in feedback control loops significantly enhanced the controller performance. For example, the cost function of the control system in the distillation column was reduced by 28∼39% when linear, adaptive linear and nonlinear DDR algorithms were used. The cost function of the controller in the cylindrical storage tank was reduced by 46% using DDR, while it was reduced by 33% when using a EWMA filter.
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Sanyal, Suman. "Stochastic dynamic equations." Diss., Rolla, Mo. : Missouri University of Science and Technology, 2008. http://scholarsmine.mst.edu/thesis/pdf/Sanyal_09007dcc80519030.pdf.
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Thesis (Ph. D.)--Missouri University of Science and Technology, 2008.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed August 21, 2008) Includes bibliographical references (p. 124-131).
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Doddapaneni, Srinivas P. "Automatic dynamic decomposition of programs on distributed memory machines." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/8158.
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Ferguson, Innes Andrew. "Touring Machines : an architecture for dynamic, rational, mobile agents." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259752.
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Wilcox, Terry Clyde. "Dynamic load balancing of virtual machines hosted on Xen /." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd2755.pdf.
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Wilcox, Terry Clyde. "Dynamic Load Balancing of Virtual Machines Hosted on Xen." BYU ScholarsArchive, 2008. https://scholarsarchive.byu.edu/etd/1654.
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Currently systems of virtual machines are load balanced statically which can create load imbalances for systems where the load changes dynamically over time. For throughput and response time of a system to be maximized it is necessary for load to be evenly distributed among each part of the system. We implement a prototype policy engine for the Xen virtual machine monitor which can dynamically load balance virtual machines. We compare the throughput and response time of our system using the cpu2000 and the WEB2005 benchmarks from SPEC. Under the loads we tested, dynamic load balancing had 5%-8% higher throughput than static load balancing.
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Elawad, Kristian. "Aiding the implementation of autonomus machines in dynamic environments." Thesis, Blekinge Tekniska Högskola, Institutionen för industriell ekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-17500.
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Background It can be observed that our society is heading more and more towards automation. Autonomous machines show large potential and are being used progressively often in a range of different areas and tasks. They are increasing the productivity and transforming jobs and industries. However, the implemented systems of autonomous machines are usually specified for certain conditions, in structured and static environments. Making the implementation very contextual to the environment it is in. Dynamic environments, is something that is continuously changing or being changed, meaning a lot of challenges for the implementation and operation of something autonomous. Objectives The purpose of this study is to investigate how to help the conditions for implementation of autonomous machines in dynamic environments. The sites and machines in the construction industry fulfill the described context well and is therefore chosen as the main field of study for this thesis. Method A main case study exploration has been used to disclose the result. Including different methods of data gathering such as literature research, interviews, observations, field visits, and workshops. Data has also been collected in form of learnings from prototypes and experiments conducted throughout the study. Results The results evaluate how the aiding of the implementation and operation of autonomous machines could be done in dynamic environments such as the construction sites. It considers working at remote areas without human assistance, the external information needed for the autonomous machines, the different technologies that could be used, and how to take a first step towards an autonomous future. A concept solution is presented, which could be implemented today and used to help the implementation and operation of autonomous machines. Conclusion The findings in this study indicates that the machines need to understand elements in dynamic environments to be able to conduct meaningful tasks. For this there is a need for external information through different technologies, making element visible in a continuously changing structure. Material management is one of the essential elements that needs to be made visible for the machines. The results can be introduced today through the concept and be developed along with the rest of the technology to make the adaptation and implementation easier.Bakgrund Det kan observeras att vårt samhälle går alltmer mot automatisering. Autonoma maskiner visar stor potential och används successivt mer för en rad olika områden och uppgifter. De ökar produktiviteten och omvandlar jobb och industrier. De implementerade systemen för autonoma maskiner är oftast specialiserade för vissa förhållanden, i strukturerade och statiska miljöer, vilket leder till att implementeringen är mycket kontextuellt för miljön. Dynamiska miljöer är något som ständigt ändras, vilket innebär en hel del utmaningar för implementeringen och driften av något autonomt och självständigt. Mål Syftet med denna studie är att undersöka hur man hjälper förutsättningarna för implementeringen av autonoma maskiner i dynamiska miljöer. Byggarbetsplatser och maskiner inom konstruktionsbranschen uppfyller det beskrivna kontexten väl och väljs därför som huvudområde för denna avhandling. Metod En explorativt fallstudie har använts för att komma fram till resultatet, tillsammans med olika metoder för datainsamling såsom litteraturundersökning, intervjuer, observationer, fältbesök och workshops. Insamling av data har även skett i form av lärdomar från prototyper och experiment som genomförts under studien. Resultat Resultaten utvärderar hur implementationen och driften av autonoma maskiner kan hjälpas i dynamiska miljöer såsom konstruktion lägen. Vidare utreds de autonoma maskinernas arbete i avlägsna områden utan mänskligt bistånd och den externa informationen som behövs för maskinerna i det sammanhanget. De olika teknologierna som kan användas är utvärderade tillsammans med hur ett första steg kan tas mot en självständig framtid. En konceptlösning presenteras, som skulle kunna implementeras idag och användas för att hjälpa till med implementering och driften av autonoma maskiner. Slutsats Resultaten i denna studie visar att maskinerna måste förstå element i dynamiska miljöer för att kunna genomföra meningsfulla uppgifter. Därför finns det behov av extern information genom olika teknologier, vilka synliggör elementet i en ständigt varierande struktur. Materialhantering är en av de väsentliga delarna som måste synliggöras för maskinerna. Resultaten kan introduceras idag genom konceptet och utvecklas tillsammans med resten av tekniken för att göra anpassningen till tekniken och implementationen enklare.
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Gorczyk, Weronika. "Dynamic processes above the subducting slab /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17543.
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Domedel-Puig, Nuria. "Bayesian analysis of dynamic cellular processes." Thesis, Birkbeck (University of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499232.
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The objective of this thesis is to show how a Bayesian model comparison framework, coupled with the use of a formal mathematical modeling language (ODEs), can assist researchers in the process of modeling dynamic biological systems. The Bayesian approach differs from classical statistics in the way model parameters are treated: our state of knowledge about them can be summarised by probability distributions. All Bayesian inference depends on the data-updated version of these parameter distributions, the posterior densities. Averaging the data likelihood over the posterior results in the model evidence, a measure that very conveniently balances the complexity of a model with the quality of its fit to the data. This is very useful for model comparison. Such a task arises quite often in biological research, where different hypotheses are often available to explain a given phenomenon, and deciding which one is best is difficult. Despite its importance, model suitability is most often judged in an informal way. The main aspects of the Bayesian approach-together with comparisons to classical statistics methods-are described in detail in the first part of this thesis. The most important formalisms for modeling biological systems are also reviewed, and the building blocks of differential equation models are presented. These methods are then applied to a series of synthetic datasets for which the underlying model is known, allowing to illustrate the main features of Bayesian inference. This is followed by the application of the framework to two real systems: a series of network motifs and the Jak/STAT signal transduction pathway. Results show that network motifs are well identifiable given dynamic data and, in the particular case of complex feedforward motif models, the Bayesian framework outperforms the classical methods. The present work also highlights the lack of an appropriate model for the flagella system, and thus a number of novel models are explored. Finally, the Jak/STAT system is analysed. The results are compared to existing models in the literature, and allow discarding some biologically-motivated new models.
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Mulder, Pieter. "Statistical process control of dynamic processes." Thesis, University of Newcastle Upon Tyne, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289209.
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Foss, Willard Rodney. "Dynamic processes in single liquid microspheres /." Thesis, Connect to this title online; UW restricted, 1995. http://hdl.handle.net/1773/9911.
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Shorr, Michael Jared. "Dynamic stability analysis for multi-flute end milling." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/17789.
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Park, Yongwon Baskiyar Sanjeev. "Dynamic task scheduling onto heterogeneous machines using Support Vector Machine." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Computer_Science_and_Software_Engineering/Thesis/Park_Yong_50.pdf.
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Shannon, Mark. "The construction of high-performance virtual machines for dynamic languages." Thesis, University of Glasgow, 2011. http://theses.gla.ac.uk/2975/.
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Dynamic languages, such as Python and Ruby, have become more widely used over the past decade. Despite this, the standard virtual machines for these languages have disappointing performance. These virtual machines are slow, not because methods for achieving better performance are unknown, but because their implementation is hard. What makes the implementation of high-performance virtual machines difficult is not that they are large pieces of software, but that there are fundamental and complex interdependencies between their components. In order to work together correctly, the interpreter, just-in-time compiler, garbage collector and library must all conform to the same precise low-level protocols. In this dissertation I describe a method for constructing virtual machines for dynamic languages, and explain how to design a virtual machine toolkit by building it around an abstract machine. The design and implementation of such a toolkit, the Glasgow Virtual Machine Toolkit, is described. The Glasgow Virtual Machine Toolkit automatically generates a just-in-time compiler, integrates precise garbage collection into the virtual machine, and automatically manages the complex inter-dependencies between all the virtual machine components. Two different virtual machines have been constructed using the GVMT. One is a minimal implementation of Scheme; which was implemented in under three weeks to demonstrate that toolkits like the GVMT can enable the easy construction of virtual machines. The second, the HotPy VM for Python, is a high-performance virtual machine; it demonstrates that a virtual machine built with a toolkit can be fast and that the use of a toolkit does not overly constrain the high-level design. Evaluation shows that HotPy outperforms the standard Python interpreter, CPython, by a large margin, and has performance on a par with PyPy, the fastest Python VM currently available.
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GOUVEA, RODRIGO MOSCONI DE. "SERVICES, PROCESSES AND MACHINES: A METHODOLOGIES STUDY FOR MACHINE REASSIGNMENT PROBLEM." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=34639@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
A organização lógica de data centers recai principalmente na questão estratégica de distribuir os serviços nos equipamentos de forma que os custos operacionais sejam os menores possíveis. Além desses custos, devem ser considerados outros aspectos que envolvem a interdependência de seus serviços internos e a distribuição entre suas localidades, visando assim melhorar a qualidade de seu produto aos seus clientes. Este trabalho explora o problema de atribuição de processos a máquinas do desafio ROADEF de 2012 pelos métodos de programação inteira e geração de colunas. Apresenta estratégias para lidar com as dificuldades numéricas encontradas. Na geração de colunas, analisa técnicas para acelerar a convergência, por meio de resolver o mestre restrito após cada variável, geração prévia de colunas e estabilização das variávies duais. Ao final do trabalho, são comparados os resultados obtidos com os melhores resultados oficiais.
A data center logic organization lies mainly by the strategic decision on how distribute services between machines, so the operational costs should be the smallest as possible. Beside those costs, must also consider the interdependence of their own services, the distribution between their localities, to improve the quality of their product to their customers. This work explores the challenge ROADEF 2012 machine assignment problem by the means of integer programming and column generation. Shows strategies to address numeric issues. At column generation, it analyzes techniques to speed up the convergence, by solving after each variable adiction, a previous generation of columns and stabilization of duals variables. At the end of the work, it compares the results obtained are compared with the best official results.
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Anderson, I. "A study of the dynamic cutting characteristics of roadheader cutting heads." Thesis, University of Newcastle Upon Tyne, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315535.
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Spies, Hagen. "Analysing dynamic processes in range data sequences." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962107271.
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Mundt, André Philipp. "Dynamic risk management with Markov decision processes." Karlsruhe Univ.-Verl. Karlsruhe, 2007. http://d-nb.info/987216511/04.
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Mundt, André Philipp. "Dynamic risk management with Markov decision processes." Karlsruhe, Baden : Universitätsverl. Karlsruhe, 2008. http://www.uvka.de/univerlag/volltexte/2008/294/.
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Avraam, Marios. "Modelling and optimisation of hybrid dynamic processes." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321942.
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Dai, Peng. "FASTER DYNAMIC PROGRAMMING FOR MARKOV DECISION PROCESSES." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/428.
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Markov decision processes (MDPs) are a general framework used by Artificial Intelligence (AI) researchers to model decision theoretic planning problems. Solving real world MDPs has been a major and challenging research topic in the AI literature. This paper discusses two main groups of approaches in solving MDPs. The first group of approaches combines the strategies of heuristic search and dynamic programming to expedite the convergence process. The second makes use of graphical structures in MDPs to decrease the effort of classic dynamic programming algorithms. Two new algorithms proposed by the author, MBLAO* and TVI, are described here.
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Chow, Yuk Tak. "Picosecond dynamic nonlinear optical processes in semiconductors." Thesis, Heriot-Watt University, 1988. http://hdl.handle.net/10399/988.
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Leisner, Jared Scott. "Dynamic and kinetic plasma processes at Saturn." Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1907990801&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Rahmandad, Hazhir. "Three essays on modeling dynamic organizational processes." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33658.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, 2005.Includes bibliographical references.
Essay 1- Effects of Feedback Delay on Learning. Learning figures prominently in many theories of organizations. Understanding barriers to learning is therefore central to understanding firms' performance. This essay investigates the role of time delays between taking an action and observing the results in impeding learning. These delays ubiquitous in real world settings can introduce important tradeoffs between the long-term and the short-term performance. In this essay, four learning algorithms, with different levels of complexity and rationality, are built and their performances in a simple resource allocation task are analyzed. The study focuses on understanding the effect of time delays on learning. Simulation analysis shows that regardless of the level of rationality of the organization, misperceived delays can impede learning significantly. Essay 2- Heterogeneity and Network Structure in the Dynamics of Diffusion: Comparing Agent-Based and Differential Equation Models When is it better to use agent-based (AB) models, and when should differential equation (DE) models be used?
(cont.) Where DE models assume homogeneity and perfect mixing within compartments, AB models can capture heterogeneity in agent attributes and in the network of interactions among them. The costs and benefits of such disaggregation should guide the choice of model type. AB models may enhance realism but entail computational and cognitive costs that may limit sensitivity analysis and model scope. Using contagious disease as an example, we contrast the dynamics of AB models with those of the analogous mean-field DE model. We examine agent heterogeneity and the impact of different network topologies, including fully connected, random, Watts-Strogatz small world, scale-free, and lattice networks. Surprisingly, in many conditions differences between the DE and AB dynamics are not statistically significant for key metrics relevant to public health, including diffusion speed, peak load on health services infrastructure and total disease burden. We discuss implications for the choice between AB and DE models, level of aggregation, and model boundary. The results apply beyond epidemiology: from innovation adoption to financial panics, many important social phenomena involve analogous processes of diffusion and social contagion.
(cont.) Essay 3- Dynamics of Multiple-release Product Development Product development (PD) is a crucial capability for firms in competitive markets. Building on case studies of software development at a large firm, this essay explores the interaction among the different stages of the PD process, the underlying architecture of the product, and the products in the field. We introduce the concept of the "adaptation trap," where intendedly functional adaptation of workload can overwhelm the PD organization and force it into firefighting (Repenning 2001) as a result of the delay in seeing the additional resource need from the field and underlying code-base. Moreover, the study highlights the importance of architecture and underlying product-base in multiple-release product development, through their impact on the quality of new models under development, as well as through resource requirements for bug-fixing. Finally, this study corroborates the dynamics of tipping into firefighting that follows quality-productivity tradeoffs under pressure. Put together, these dynamics elucidate some of the reasons why PD capability is hard to build and why it easily erodes.
(cont.) Consequently, we offer hypotheses on the characteristics of the PD process that increase its strategic significance and discuss some practical challenges in the face of these dynamics.
by Hazhir Rahmandad.
Ph.D.
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MacNish, Craig Gordon. "Nonmonotonic inference systems for modelling dynamic processes." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240195.
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Xie, Chen. "DYNAMIC DECISION APPROXIMATE EMPIRICAL REWARD (DDAER) PROCESSES." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1398991609.
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Jarvis, Richard Barry. "Robust dynamic simulation of chemical engineering processes." Thesis, Imperial College London, 1993. http://hdl.handle.net/10044/1/7309.
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Gassenmeier, Martina. "Observation of dynamic processes with seismic interferometry." Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-203118.
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In this study, seismic interferometry is used to analyze dynamic processes in the Earth’s shallow subsurface caused by environmental processes and ground shaking. In the first part of the thesis, the feasibility of a passive monitoring with ambient seismic noise at the pilot site for CO2 injection in Ketzin is investigated. Monitoring the expansion of the CO2 plume is essential for the characterization of the reservoir as well as the detection of potential leakage. From June 2008 until August 2013, more than 67000 tons of CO2 were injected into a saline aquifer at a depth of about 650 m. Passive seismic data recorded at a seismic network around the injection site was cross-correlated in a frequency range of 0.5-4.5 Hz over a period of 4 years. The frequency band of 0.5-0.9 Hz, in which surface waves exhibit a high sensitivity at the depth of the reservoir, is not suitable for monitoring purposes as it is only weakly excited. In a frequency range of 1.5-3 Hz, periodic velocity variations with a period of approximately one year are found that cannot be caused by the CO2 injection. The prominent propagation direction of the noise wave field indicates a wind farm as the dominant source providing the temporally stable noise field. This spacial stability excludes variations of the noise source distribution as a spurious cause of velocity variations. Based on an amplitude decrease associated with time windows towards later parts of the coda, the variations must be generated in the shallow subsurface. A comparison to groundwater level data reveals a direct correlation between depth of the groundwater level and the seismic velocity. The influence of ground frost on the seismic velocities is documented by a sharp increase of velocity when the maximum daily temperature stays below 0 C. Although the observed periodic changes and the changes due to ground frost affect only the shallow subsurface, they mask potential signals of material changes from the reservoir depths. To investigate temporal seismic velocity changes due to earthquake-related processes and environmental forcing in northern Chile, 8 years of ambient seismic noise recorded by the Integrated Plate Boundary Observatory Chile (IPOC) are analyzed. By autocorrelating the ambient seismic noise field, approximations of the Green’s functions are retrieved and velocity changes are measured with Coda Wave Interferometry. At station PATCX, seasonal changes of seismic velocity caused by thermal stress as well as transient velocity reductions are observed in the frequency range of 4-6 Hz. Sudden velocity drops occur at times of mostly earthquake-induced ground describing the seismic velocity variations based on continuous observations of the local ground acceleration. The model assumes that not only the shaking of large earthquakes causes velocity drops, but any small vibrations continuously induce minor velocity variations that are immediately compensated by healing in the steady state. The shaking effect is accumulated over time and best described by the integrated envelope of the ground acceleration over one day, which is the temporal resolution of the velocity measurements. In the model, the amplitude of the velocity reduction as well as the recovery time are proportional to the strength of the excitation. The increase of coseismic velocity change and recovery time with increasing excitation is confirmed by laboratory tests with ultrasound. Despite having only two free scaling parameters, the model fits the data of the shaking-induced velocity variation in remarkable detail. Additionally, a linear trend is observed that might be related to a recovery process from one or more earthquakes before the measurement period. A clear relationship between ground shaking and induced velocity reductions is not visible at other stations. The outstanding sensitivity of PATCX to ground shaking and thermal stress can be attributed to the special geological setting of the station, where the subsurface material consists of a relatively loose conglomerate with high pore volume leading to stronger nonlinearity compared to the other IPOC stationsIn dieser Studie werden mit Hilfe von seismischer Interferometrie kleinste dynamische Prozesse in der Erdkruste beobachtet, welche beispielsweise durch umweltbedingte oder anthropogene Einflüsse sowie Bodenerschütterungen hervorgerufen werden können. Im ersten Teil der Arbeit werden Änderungen in der seismischen Geschwindigkeit am Pilotstandort für CO2-Speicherung in Ketzin untersucht. In einer Tiefe von 650m wurden dort zwischen Juni 2008 und August 2013 über 67000 Tonnen CO2 eingelagert. In einem Frequenzbereich vom 0,05-4,5 Hz wurden Kreuzkorrelationen des seismischen Hintergrundrauschens an einem kleinräumigen Netzwerk über einen Zeitraum von 4 Jahren berechnet. Der Frequenzbereich zwischen 0,5 und 0,9 Hz weist eine hohe Sensitivität von Oberflächenwellen in der Tiefe des Reservoirs auf, ist aber nur sehr schwach angeregt und eignet sich deswegen nicht für die Analyse. In einem Frequenzbereich von 1,5-3 Hz zeigen sich periodische Geschwindigkeitsänderungen mit einer Periode von einem Jahr, welche nicht durch die Einlagerung von CO2 erzeugt werden können. Eine Analyse des seismischen Hintergrundrauschens zeigt, dass dieses über den gesamten Zeitraum hinweg hauptsächlich aus der Richtung eines Windparks kommt. Durch die Stabilität des Wellenfeldes können Änderungen in den Quellpositionen, welche sich in scheinbaren Geschwindigkeitsänderungen zeigen können, ausgeschlossen werden. Eine Amplitudenabnahme der Geschwindigkeitsänderungen hin zu späteren Zeitfenstern in der Coda lässt auf oberflächennahe Prozesse als Ursache schließen. Ein Vergleich zwischen den jährlichen Geschwindigkeitsänderungen mit Schwankungen im Grundwasserspiegel zeigt eine direkte Korrelation. Ein sprunghafter Anstieg in der Geschwindigkeit zeigt sich im Winter, wenn die Tageshöchsttemperaturen unter den Gefrierpunkt sinken und der Boden zufriert. Obwohl Bodenfrost und Änderungen im Grundwasserspiegel nur einen sehr oberflächennahen Bereich betreffen, so überdecken sie dennoch mögliche Signale durch die Einlagerung von CO2. Im zweiten Teil der Arbeit werden Geschwindigkeitsänderungen in Nordchile untersucht, welche durch erdbebeninduzierte Prozesse und umweltbedingte Einflüsse hervorgerufen werden. Dazu wurden über einen Zeitraum von 8 Jahren Autokorrelationen des seismischen Hintergrundrauschens des IPOC Netzwerkes (Integrated Plate Boundary Observatory Chile) berechnet und mit seismischer Interferometrie ausgewertet. An der Station PATCX können in einem Frequenzbereich von 4-6 Hz periodische Geschwindigkeitsänderungen beobachet werden, welche durch thermisch induzierte Dehnung hervorgerufen werden. Außerdem treten transiente Geschwindigkeitsabnamen nach Bodenerschütterungen auf, welche hauptsächlich von Erdbeben verursacht werden. Die seismische Geschwindigkeit kehrt daraufhin langsam wieder auf ihr vorheriges Niveau zurück. Für die Geschwindigkeitsänderungen wurde ein empirisches Modell entwickelt, welches auf Messungen der lokalen Bodenerschütterung basiert. Dabei wird angenommen, dass nicht nur große erdbebeninduzierte, sondern auch kleinste Bodenerschütterungen einen Abfall der Geschwindigkeit erzeugen, welche wiederum innerhalb kürzester Zeit durch Heilung in den Gleichgewichtszustand zurückkehrt. Dabei summieren sich die Effekte durch die Bodenerschütterungen mit der Zeit auf und werden am besten mit dem Integral der lokalen Bodenbeschleunigung über die Messwerte eines Tages beschrieben. Die Diskretisierung von einem Tag entspricht der zeitlichen Auflösung in der Messung der Geschwindigkeitsänderungen. Sowohl die Amplitude der Geschwindigkeitsabnahme als auch die Zeit bis der Gleichgewichtszustand wieder erreicht ist (Heilungszeit) werden im Modell als proportinal zur Größe der Anregung angenommen. Eine Korrelation der Heilungszeit und der Amplitude der koseismischen Geschwindigkeitsabnahme mit der Größe der Anregung konnte mit Hilfe von Laboruntersuchungen mit Ultraschall bestätigt werden. Mit nur zwei Parametern beschreibt das Modell die transienten Geschwindigkeitsänderungen in bemerkenswerter Genauigkeit. Desweiteren beinhaltet das Modell einen linearen Verlauf in den Geschwindigkeitsänderungen, welcher vermutlich durch einen Heilungsprozess hervorgerufen wird, der auf ein oder mehrere Erdbeben vor dem Messzeitraum folgte. Eine Beziehung zwischen Bodenerschütterung und Geschwindigkeitsänderung ist an anderen Stationen des IPOC Netzwerkes nicht erkennbar. Die herausragende Sensitivität von PATCX im Hinblick auf Bodenerschütterung und thermische Dehnung kann den speziellen geologischen Gegebenheiten an der Station zugeschrieben werden. Bei dem dort vorliegenden Material handelt es sich um ein relativ loses Konglomerat mit großem Porenvolumen, welches ein starkes nichtlineares Verhalten aufweist, was an anderen IPOC Stationen nicht zu erwarten ist