• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 22
  • 5
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 49
  • 49
  • 7
  • 7
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 5
  • 4
  • 4
  • 3
  • 3
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Kontrola kvality průmyslových výrobků / Quality control of industrial products

ŠVARCOVÁ, Lenka January 2016 (has links)
The aim of this thesis is to find out a way of applying the modern methods of quality control in the industrial company and suggestion of some recommendations for small and medium-sized enterprises. The thesis is composed of theoretical and practical parts. In the theoretical part of this work are compiled notions relevant to the issue. The practical part of the work consists of the results of the analysis of the applied methods of quality controls in the business, which with a kind of a way of service controls the product quality in other businesses. The end of the thesis contains suggestions and recommendations resulting from the practical part.
32

Estrutura populacional e avaliação de métodos de controle da espécie exótica invasora Artocarpus heterophyllus Lamk. (Moraceae) no Parque Estadual da Ilha Grande, Angra do Reis, RJ Rio de Janeiro 2011 / Population structure and evaluation of a control method for the exotic invasive species Artocarpus heterophyllus Lamk (Moraceae) in Ilha Grande State Park, RJ, Brazil

Ciro José Ribeiro de Moura 25 February 2011 (has links)
Atualmente, com o aumento no número de estudos sobre invasões biológicas, sabemos como ocorre o processo, suas causas e conseqüências. A prevenção ainda é a melhor maneira de limitar e diminuir o aumento no número de problemas associados às espécies exóticas e invasoras biológicas. A jaqueira, Artocarpus heterophyllus Lamk. (Moraceae), é uma espécie exótica invasora que foi introduzida no Brasil no período colonial. A principal estratégia de controle de A. heterophyllus tem sido o método mecânico conhecido como anelamento e o arranque de plântulas. Utilizando o Manual da TNC para Controle de Espécies Invasoras, este estudo objetivou propor um novo método de controle da jaqueira, e caracterizar a estrutura populacional da espécie. O estudo foi conduzido na Ilha Grande, localizada no município de Angra dos Reis, RJ, que é coberta por Mata Atlântica em diferentes estágios sucessionais. Testou-se um novo método químico que consistiu na injeção de herbicida Garlon diluído a 4% no tronco de árvores com DAP>15 cm. Ao todo 684 indivíduos distribuídos em 10 parcelas medindo 0,64 ha cada foram encontrados. A densidade media encontrada foi de 107 ind. / ha, com densidades variando entre 3340 ind. / ha, na classe Juvenis 1 (DAP < 5 cm) a 13 ind / ha na classe Adltos 2 (20.1 <DAP> 25.0). A área basal média encontrada foi de 3,692 m / ha. Os resultados mostraram que o método químico foi mais eficiente que o método mecânico. Após 60, 150 e 240 dias do tratamento inicial, os métodos diferiram significativamente. Os resultados demonstram que não há correlação entre a eficiência do método mecânico em relação ao DAP. Entretanto o método químico é dependente do DAP. Os resultados das taxas de mortalidade foram significantes para o tempo de resposta aos 60 dias (p = 0,009), 150 dias (p = 0,039) e 240 dias (p = 0.013), após teste estatístico Kruskal Wallis. As vantagens do método químico em relação ao mecânico são claras, onde menos dinheiro é gasto e mais resultados são gerados. / Currently, with the increasing number of studies on biological invasions, we know how this process occurs, its causes and inherent consequences. Prevention is still the best way to limit and reduce the increasing number of problems associated with exotic and invasive species biology. Jackfruit, Artocarpus heterophyllus Lamk. (Moraceae) is an invasive alien species that was introduced in Brazil during the colonial period. The main strategy for controlling A. heterophyllus has been a mechanical method known as girdling and remove seedlings. Using the Manual for the Nature Conservancy Invasive Species Control, this study aimed at proposing a new control method of jackfruit, and characterize the population structure of the species. The study was conducted in Ilha Grande, located in Angra dos Reis, RJ, which is covered by Atlantic forest in different successional stages. We tested a new chemical method which consisted of injecting herbicide Garlon diluted to 4% into the trunk of trees with DBH> 15 cm. The total of individuals sampled in 10 plots mesuring 0,64 ha each, was 684 plants. The average density was 107 individuals / ha, with densities ranging from 3340 ind / ha on the class Youth 1 (DBH <5) to 13 ind. / ha on class Adults 2 (20.1 <DBH> 25.0). The average basal area was 3,692 m / ha. The results showed that the chemical method was more efficient than the mechanical method. The methods differed significantly after 60, 150 and 240 days of initial treatment. The results show no correlation of the mechanical method to DBH. However, the chemical method is dependent on DBH. The results showed significance with time 60 days (p = 0,009), 150 days (p = 0,039) and 240 days (p = 0.013), after analysis with the statistical test of KruskalWallis. Its now clear what the advantages of the chemical method are when comparing to the mechanical method. Less money is spent and more results are generated.
33

Estrutura populacional e avaliação de métodos de controle da espécie exótica invasora Artocarpus heterophyllus Lamk. (Moraceae) no Parque Estadual da Ilha Grande, Angra do Reis, RJ Rio de Janeiro 2011 / Population structure and evaluation of a control method for the exotic invasive species Artocarpus heterophyllus Lamk (Moraceae) in Ilha Grande State Park, RJ, Brazil

Ciro José Ribeiro de Moura 25 February 2011 (has links)
Atualmente, com o aumento no número de estudos sobre invasões biológicas, sabemos como ocorre o processo, suas causas e conseqüências. A prevenção ainda é a melhor maneira de limitar e diminuir o aumento no número de problemas associados às espécies exóticas e invasoras biológicas. A jaqueira, Artocarpus heterophyllus Lamk. (Moraceae), é uma espécie exótica invasora que foi introduzida no Brasil no período colonial. A principal estratégia de controle de A. heterophyllus tem sido o método mecânico conhecido como anelamento e o arranque de plântulas. Utilizando o Manual da TNC para Controle de Espécies Invasoras, este estudo objetivou propor um novo método de controle da jaqueira, e caracterizar a estrutura populacional da espécie. O estudo foi conduzido na Ilha Grande, localizada no município de Angra dos Reis, RJ, que é coberta por Mata Atlântica em diferentes estágios sucessionais. Testou-se um novo método químico que consistiu na injeção de herbicida Garlon diluído a 4% no tronco de árvores com DAP>15 cm. Ao todo 684 indivíduos distribuídos em 10 parcelas medindo 0,64 ha cada foram encontrados. A densidade media encontrada foi de 107 ind. / ha, com densidades variando entre 3340 ind. / ha, na classe Juvenis 1 (DAP < 5 cm) a 13 ind / ha na classe Adltos 2 (20.1 <DAP> 25.0). A área basal média encontrada foi de 3,692 m / ha. Os resultados mostraram que o método químico foi mais eficiente que o método mecânico. Após 60, 150 e 240 dias do tratamento inicial, os métodos diferiram significativamente. Os resultados demonstram que não há correlação entre a eficiência do método mecânico em relação ao DAP. Entretanto o método químico é dependente do DAP. Os resultados das taxas de mortalidade foram significantes para o tempo de resposta aos 60 dias (p = 0,009), 150 dias (p = 0,039) e 240 dias (p = 0.013), após teste estatístico Kruskal Wallis. As vantagens do método químico em relação ao mecânico são claras, onde menos dinheiro é gasto e mais resultados são gerados. / Currently, with the increasing number of studies on biological invasions, we know how this process occurs, its causes and inherent consequences. Prevention is still the best way to limit and reduce the increasing number of problems associated with exotic and invasive species biology. Jackfruit, Artocarpus heterophyllus Lamk. (Moraceae) is an invasive alien species that was introduced in Brazil during the colonial period. The main strategy for controlling A. heterophyllus has been a mechanical method known as girdling and remove seedlings. Using the Manual for the Nature Conservancy Invasive Species Control, this study aimed at proposing a new control method of jackfruit, and characterize the population structure of the species. The study was conducted in Ilha Grande, located in Angra dos Reis, RJ, which is covered by Atlantic forest in different successional stages. We tested a new chemical method which consisted of injecting herbicide Garlon diluted to 4% into the trunk of trees with DBH> 15 cm. The total of individuals sampled in 10 plots mesuring 0,64 ha each, was 684 plants. The average density was 107 individuals / ha, with densities ranging from 3340 ind / ha on the class Youth 1 (DBH <5) to 13 ind. / ha on class Adults 2 (20.1 <DBH> 25.0). The average basal area was 3,692 m / ha. The results showed that the chemical method was more efficient than the mechanical method. The methods differed significantly after 60, 150 and 240 days of initial treatment. The results show no correlation of the mechanical method to DBH. However, the chemical method is dependent on DBH. The results showed significance with time 60 days (p = 0,009), 150 days (p = 0,039) and 240 days (p = 0.013), after analysis with the statistical test of KruskalWallis. Its now clear what the advantages of the chemical method are when comparing to the mechanical method. Less money is spent and more results are generated.
34

Estudo de campo para avaliação da efetividade de vacinação e de uso de coleiras impregnadas com inseticidas para o controle da leishmaniose visceral canina / Field study to evaluate the effectiveness of vaccination and insecticides impregnated collars to control canine visceral leishmaniasis

Lopes, Estela Gallucci 21 September 2015 (has links)
As leishmanioses e particularmente a leishmaniose visceral (LV) são doenças transmitidas por vetores artrópodes candidatas a experimentar uma grande expansão territorial em virtude de problemas relacionados ao aquecimento global. Este evento climático deverá causar grande impacto sobre a distribuição geográfica do artrópode transmissor no Brasil e no mundo. Com efeito, nos últimos 20 anos a situação epidemiológica da LV no Brasil vem se modificando de um padrão esporádico prevalente eminentemente em áreas rurais para uma condição de epidemias peri-urbanas que pode afetar todos os estratos sociais da população, tornando-se uma séria ameaça à saúde pública. As leishmanioses são consideradas até o momento doenças não preveníveis e seu padrão epidemiológico vêm se alterando de forma flagrante, o que demanda urgência para o desenvolvimento de novas ferramentas de controle e tratamento. Dentre as diversas questões levantadas sobre as demandas em pesquisa relacionadas ao controle desta enfermidade, destaca-se a importância de avanços em estudos de epidemiologia quantitativa e modelagem matemática que permitam prever efeitos de vacinações de populações empregando-se imunógenos com eficácia e/ou cobertura vacinal menor que 100%, o que parece ser uma realidade com as vacinas contra leishmanioses desenvolvidas até então pelos laboratórios no mundo todo. O sucesso de estratégias eficazes para o controle da LV depende do conhecimento de diversos parâmetros da dinâmica de infecção nas diferentes populações e espécies que atuam na cadeia epidemiológica da doença. Esse estudo teve objetivo de avaliar a efetividade de vacinas contra leishmaniose em cães bem como da utilização de coleira impregnada com inseticida através de um estudo de coorte realizado em uma região de transmissão moderada de leishmaniose visceral canina. Foram construídas seis coortes compostas por animais não reagentes ao teste rápido TR-DPP&reg; e ao teste EIE-ELISA&reg;. Todos os animais apresentaram estado clínico normal, conforme avaliação semiológica. As coortes compreendem grupos de animais sem qualquer medida de controle (grupo N), grupos de animais com aplicação de coleira (grupo C), grupos de animais vacinados com vacina de subunidade (grupo V1) e grupos de animais vacinados com vacina recombinante (grupo V2) e grupos de animais vacinados e com coleira (grupos V1C e V2C). Foram colhidas amostras de todas as coortes em três tempos com intervalo de seis meses cada, para sorodiagnóstico. A efetividade encontrada ao final de 12 meses de observação para os grupos C, V1, V2, V1C e V2C foram 38,2%, 58,1%, 35%, 68,6% e -36,5% respectivamente com base nos cálculos estatísticos feitos por regressão de Cox para riscos proporcionais. Todas as coortes, mesmo tendo desempenhando alguma efetividade exceto V2C, os resultados dos intervalos de confiança do risco relativo não foram significativos quando comparados ao grupo controle (N). / Leishmaniasis and particularly the LV are diseases transmitted by arthropod vectors candidates to experience a wide territorial expansion because of problems related to global warming. This weather event should cause great impact on the geographical distribution of the arthropod transmitter in Brazil and worldwide. Indeed, the past 20 years the epidemiological situation of LV in Brazil has been changing a prevalent sporadic pattern predominantly in rural areas to a condition of peri-urban epidemics that can affect all social strata of the population, making it a serious threat public health. Leishmaniasis are considered so far not preventable disease and its epidemiological pattern have been changing blatantly, which requires urgency to the development of new tools for control and treatment. Among the many questions raised about the demands on research related to the control of this disease, it highlights the importance of advances in quantitative epidemiological studies and mathematical modeling to anticipate vaccinations effects of employing immunogens effectively and / or lower vaccination coverage to 100%, which appears to be a reality with vaccines against leishmaniasis developed so far by laboratories worldwide. The success of effective strategies to control the LV depends on the knowledge of many aspects of the dynamics of infection in different populations and species that act in the epidemiological chain of the disease. This study aims to evaluate the effectiveness of vaccines against leishmaniasis in dogs as well as the use of insecticide impregnated collar with through a cohort study in a high transmission of canine visceral leishmaniasis region. It was built six cohorts composed of non-reactive animals to the rapid test DPP&reg; and EIE-ELISA&reg; test. All the animals had normal clinical status, as symptomatic evaluation. The cohorts include groups of animals without any measure of control (group N), group of animals with collar application (group C), groups of vaccinated animals with subunit vaccine (group V1), group of animals vaccinated with recombinant vaccine (group V2) and groups of animals vaccinated and collar application (V1C and V2C). Samples were collected from all cohorts in three times at intervals of six months each for serodiagnosis. The effectiveness found after 12 months of observation for groups C, V1, V2, V1C and V2C were 38.2%, 58.1%, 35%, 68.6% and -36.5% respectively based on the statistical calculations done by Cox proportional hazards regression to. All cohorts, even though playing some effectiveness except V2C, the results of risk relative confidence intervals were not significant when compared to the control group (N).
35

Estudo de campo para avaliação da efetividade de vacinação e de uso de coleiras impregnadas com inseticidas para o controle da leishmaniose visceral canina / Field study to evaluate the effectiveness of vaccination and insecticides impregnated collars to control canine visceral leishmaniasis

Estela Gallucci Lopes 21 September 2015 (has links)
As leishmanioses e particularmente a leishmaniose visceral (LV) são doenças transmitidas por vetores artrópodes candidatas a experimentar uma grande expansão territorial em virtude de problemas relacionados ao aquecimento global. Este evento climático deverá causar grande impacto sobre a distribuição geográfica do artrópode transmissor no Brasil e no mundo. Com efeito, nos últimos 20 anos a situação epidemiológica da LV no Brasil vem se modificando de um padrão esporádico prevalente eminentemente em áreas rurais para uma condição de epidemias peri-urbanas que pode afetar todos os estratos sociais da população, tornando-se uma séria ameaça à saúde pública. As leishmanioses são consideradas até o momento doenças não preveníveis e seu padrão epidemiológico vêm se alterando de forma flagrante, o que demanda urgência para o desenvolvimento de novas ferramentas de controle e tratamento. Dentre as diversas questões levantadas sobre as demandas em pesquisa relacionadas ao controle desta enfermidade, destaca-se a importância de avanços em estudos de epidemiologia quantitativa e modelagem matemática que permitam prever efeitos de vacinações de populações empregando-se imunógenos com eficácia e/ou cobertura vacinal menor que 100%, o que parece ser uma realidade com as vacinas contra leishmanioses desenvolvidas até então pelos laboratórios no mundo todo. O sucesso de estratégias eficazes para o controle da LV depende do conhecimento de diversos parâmetros da dinâmica de infecção nas diferentes populações e espécies que atuam na cadeia epidemiológica da doença. Esse estudo teve objetivo de avaliar a efetividade de vacinas contra leishmaniose em cães bem como da utilização de coleira impregnada com inseticida através de um estudo de coorte realizado em uma região de transmissão moderada de leishmaniose visceral canina. Foram construídas seis coortes compostas por animais não reagentes ao teste rápido TR-DPP&reg; e ao teste EIE-ELISA&reg;. Todos os animais apresentaram estado clínico normal, conforme avaliação semiológica. As coortes compreendem grupos de animais sem qualquer medida de controle (grupo N), grupos de animais com aplicação de coleira (grupo C), grupos de animais vacinados com vacina de subunidade (grupo V1) e grupos de animais vacinados com vacina recombinante (grupo V2) e grupos de animais vacinados e com coleira (grupos V1C e V2C). Foram colhidas amostras de todas as coortes em três tempos com intervalo de seis meses cada, para sorodiagnóstico. A efetividade encontrada ao final de 12 meses de observação para os grupos C, V1, V2, V1C e V2C foram 38,2%, 58,1%, 35%, 68,6% e -36,5% respectivamente com base nos cálculos estatísticos feitos por regressão de Cox para riscos proporcionais. Todas as coortes, mesmo tendo desempenhando alguma efetividade exceto V2C, os resultados dos intervalos de confiança do risco relativo não foram significativos quando comparados ao grupo controle (N). / Leishmaniasis and particularly the LV are diseases transmitted by arthropod vectors candidates to experience a wide territorial expansion because of problems related to global warming. This weather event should cause great impact on the geographical distribution of the arthropod transmitter in Brazil and worldwide. Indeed, the past 20 years the epidemiological situation of LV in Brazil has been changing a prevalent sporadic pattern predominantly in rural areas to a condition of peri-urban epidemics that can affect all social strata of the population, making it a serious threat public health. Leishmaniasis are considered so far not preventable disease and its epidemiological pattern have been changing blatantly, which requires urgency to the development of new tools for control and treatment. Among the many questions raised about the demands on research related to the control of this disease, it highlights the importance of advances in quantitative epidemiological studies and mathematical modeling to anticipate vaccinations effects of employing immunogens effectively and / or lower vaccination coverage to 100%, which appears to be a reality with vaccines against leishmaniasis developed so far by laboratories worldwide. The success of effective strategies to control the LV depends on the knowledge of many aspects of the dynamics of infection in different populations and species that act in the epidemiological chain of the disease. This study aims to evaluate the effectiveness of vaccines against leishmaniasis in dogs as well as the use of insecticide impregnated collar with through a cohort study in a high transmission of canine visceral leishmaniasis region. It was built six cohorts composed of non-reactive animals to the rapid test DPP&reg; and EIE-ELISA&reg; test. All the animals had normal clinical status, as symptomatic evaluation. The cohorts include groups of animals without any measure of control (group N), group of animals with collar application (group C), groups of vaccinated animals with subunit vaccine (group V1), group of animals vaccinated with recombinant vaccine (group V2) and groups of animals vaccinated and collar application (V1C and V2C). Samples were collected from all cohorts in three times at intervals of six months each for serodiagnosis. The effectiveness found after 12 months of observation for groups C, V1, V2, V1C and V2C were 38.2%, 58.1%, 35%, 68.6% and -36.5% respectively based on the statistical calculations done by Cox proportional hazards regression to. All cohorts, even though playing some effectiveness except V2C, the results of risk relative confidence intervals were not significant when compared to the control group (N).
36

Dateneffiziente selbstlernende neuronale Regler

Hafner, Roland 04 December 2009 (has links)
Die vorliegende Arbeit untersucht den Entwurf und die Anwendung selbstlernender Regler als intelligente Reglerkomponente im Wirkungsablauf eines Regelkreises für regelungstechnische Anwendungen. Der aufwändige Prozess der Analyse des dynamischen Systems und der Reglersynthese, welche die klassischen Entwurfsmuster der Regelungstechnik benötigen, wird dabei ersetzt durch eine lernende Reglerkomponente. Diese kann mit sehr wenig Wissen über den zu regelnden Prozess eingesetzt werden und lernt direkt durch Interaktion eine präzise Regelung auf extern vorgegebene Führungsgrößen. Der Lernvorgang basiert dabei auf einem Optimierungsprozess mit einem leistungsfähigen Batch-Reinforcement-Lernverfahren, dem ´Neural Fitted Q-Iteration´. Dieses Verfahren wird auf seine Verwendung als selbstlernender Regler untersucht. Für die in den Untersuchungen festgestellten Unzulänglichkeiten des Verfahrens bezüglich der geforderten präzisen, zeitoptimalen Regelung werden verbesserte Vorgehensweisen entwickelt, die ebenfalls auf ihre Leistungsfähigkeit untersucht werden.Für typische regelungstechnische Problemstellungen sind die diskreten Aktionen des NFQ-Verfahrens nicht ausreichend, um eine präzise Regelung auf beliebige Führungsgrößen zu erzeugen.Durch die Entwicklung einer Erweiterung des NFQ für kontinuierliche Aktionen wird die Genauigkeit und Leistungsfähigkeit der selbstlernenden Regler drastisch erhöht, ohne die benötigte Interaktionszeit am Prozess zu erhöhen.An ausgewählten Problemen der Regelung linearer und nichtlinearer Prozesse wird die Leistungsfähigkeit der entwickelten Verfahren empirisch evaluiert. Es zeigt sich dabei, dass die hier entwickelten selbstlernenden Regler mit wenigen Minuten Interaktionszeit an einem Prozess eine präzise Regelungsstrategie für beliebige externe Führungsgrößen lernen, ohne dass Expertenwissen über den Prozess vorliegt.
37

Selbst-adaptive modellbasierte Entscheidungsunterstützungssysteme - Konzeption, prototypische Implementierung und Evaluation einer Architektur für selbst-adaptive Entscheidungsunterstützungsmodelle

Breuer, Marcel-Philippe 06 May 2020 (has links)
In der vorliegenden Arbeit wird ein selbst-adaptives modellbasiertes Entscheidungsunterstützungssystem zur Anpassung von Modellen an eine dynamische Umwelt im Rahmen des betriebswirtschaftlichen Planungsprozesses beschrieben. Das Prinzip der Selbst-Adaption wird genutzt, um Modelle innerhalb eines Entscheidungsunterstützungssystems kontinuierlich realitätsnah zu repräsentieren, damit ein Entscheider stetig bestmöglich unterstützt werden kann. Hierfür wird eine Architektur entwickelt, die ein modellgetriebenes Entscheidungsunterstützungssystem auf Grundlage des Prinzips der Selbst-Adaption konzeptionell erweitert und prototypisch realisiert. Die konzipierte Model-/System-Controller Architektur besteht aus vier zentralen Komponenten: Dem Modell als Abbild der Realität, dem System-Controller zur Anwendung des Modells sowie zur Unterstützung des Anwenders, dem Observer zur Überwachung der Modellvalidität und dem Model-Controller zur Erstellung von Modellanpassungsvorschlägen im Fall einer Abweichung. Der Observer überwacht das Modell und prüft kontinuierlich, ob eine Modellaktualisierung notwendig ist. Der Model-Controller sorgt durch ein dynamisches Vorgehen beim Erstellen von Experimentalmodellen sowie eine vielschichtige Evaluation auf Modell- und Variablenebene für eine Reduktion der Komplexität. Das Zusammenspiel der Komponenten sorgt für eine kontinuierliche Evaluation und, sofern es die Umweltbedingungen bedürfen, für eine ständige Anpassung des Modells. Forschungsmethodisch orientiert sich die Arbeit an Design Science Research. Die gestaltungsorientierten Forschungsschritte werden durch eine ex ante und ex post Evaluation überprüft. Die ex ante Evaluation überprüft die Architektur auf Vollständigkeit und Korrektheit und bestätigt im Rahmen einer Umfrage, dass die entwickelten Komponenten sowie ihre Funktionen die Probleme von Entscheidungsunterstützungssystemen in einer dynamischen Unternehmensumwelt lindern können. Die ex post Evaluation weist mittels eines Laborexperimentes die Effektivität und Effizienz bei der Abweichungs- und Ursachenanalyse des Prototyps nach und zeigt die Gebrauchstauglichkeit für verschiedene Nutzungsszenarien auf.
38

Relevance-based Online Planning in Complex POMDPs

Saborío Morales, Juan Carlos 17 July 2020 (has links)
Planning under uncertainty is a central topic at the intersection of disciplines such as artificial intelligence, cognitive science and robotics, and its aim is to enable artificial agents to solve challenging problems through a systematic approach to decision-making. Some of these challenges include generating expectations about different outcomes governed by a probability distribution and estimating the utility of actions based only on partial information. In addition, an agent must incorporate observations or information from the environment into its deliberation process and produce the next best action to execute, based on an updated understanding of the world. This process is commonly modeled as a POMDP, a discrete stochastic system that becomes intractable very quickly. Many real-world problems, however, can be simplified following cues derived from contextual information about the relative expected value of actions. Based on an intuitive approach to problem solving, and relying on ideas related to attention and relevance estimation, we propose a new approach to planning supported by our two main contributions: PGS grants an agent the ability to generate internal preferences and biases to guide action selection, and IRE allows the agent to reduce the dimensionality of complex problems while planning online. Unlike existing work that improves the performance of planning on POMDPs, PGS and IRE do not rely on detailed heuristics or domain knowledge, explicit action hierarchies or manually designed dependencies for state factoring. Our results show that this level of autonomy is important to solve increasingly more challenging problems, where manually designed simplifications scale poorly.
39

Применение интеллектуального анализа данных для повышения эффективности производства промышленного предприятия : магистерская диссертация / The use of data mining to improve the production efficiency of an industrial enterprise

Колосовникова, Е. Ф., Kolosovnikova, Е. Ф. January 2019 (has links)
Проблема формирования эффективной системы контроля качества является актуальной, т.к. высокий процент брака на производстве приводят к ухудшению производственных и финансово-экономических показателей деятельности организаций. Целью исследования является развитие контроля качества изготавливаемой продукции. Научная новизна исследования заключается в совершенствовании существующих методик контроля качества изготавливаемой продукции. Практическая значимость работы заключается в возможности применения ее результатов организациями для формирования системы контроля качества и управления ею. Экономический эффект от применения мероприятий по уменьшению доли брака за год – 420 000 рублей. Срок окупаемости проекта составляет 12 месяцев, что говорит об эффективности проекта. / The problem of creating an effective quality control system is relevant, because a high percentage of rejects in production leads to a deterioration in the production and financial and economic performance of organizations. The aim of the study is the development of quality control of manufactured products. The scientific novelty of the study is to improve existing methods of quality control of manufactured products. The practical significance of the work lies in the possibility of applying its results by organizations to form a quality control system and manage it. The economic effect of the application of measures to reduce the share of marriage per year is 420,000 rubles. The payback period of the project is 12 months, which indicates the effectiveness of the project.
40

Novel control techniques in multiphase drives : direct control methods (DTC and MPC) under limit situations / Nouvelles techniques de commande pour les entraînements électriques polyphasés : commande en mode instantané (DTC et MPC) dans des situations limites

Bermúdez guzmán, Mario 21 December 2018 (has links)
Les entraînements électriques polyphasés ont acquis une importance particulière ces derniers temps pour leur utilisation dans des applications où la fiabilité présente un intérêt pour des raisons économiques et de sécurité. Cette thèse se centre sur le développement de techniques de commande en mode instantané pour contrôler de manière optimale les machines polyphasées, en analysant leur tolérance dans différentes conditions de fonctionnement, telles que lors de l’atteinte de limites électriques (limites de tension, de courant et de niveau maximum de magnétisation) ou de défauts de type phase ouverte. Tout d’abord, la technique DTC est proposée pour gérer le cas de défaut de type phase ouverte dans la machine polyphasée. Une comparaison de la tolérance à la défaillance des commandes de type DTC par rapport à d’autres techniques de commande est réalisée, permettant une conclusion sur les forces et les faiblesses des méthodes analysées. Enfin, un contrôleur de courant optimal est développé utilisant des techniques MPC permettant une utilisation optimale de la capacité de couple du système en cas de limitations électriques. Des résultats de simulation et des validations expérimentales sont effectués pour corroborer les approches initiales, en utilisant des cas particuliers d’entraînements pentaphasés commandés avec différents sous-espaces de commande dans le domaine fréquentiel. / Multiphase drives have gained special relevance in recent times for their use in applications where reliability is of interest for economical and safety reasons. This Thesis focuses on the development of direct control techniques to optimally control multiphase machines, analyzing their tolerance to different limit operating conditions, such as electrical constraints (voltage, current and magnetization level limits) or failure situations such as an open-phase fault. First, the DTC technique is proposed to manage the open-phase fault operation of the multiphase machine. A comparison of the fault-tolerant capability of DTC with other control techniques is carried out, to conclude the strengths and weaknesses of the analyzed methods facing this limit operation. Finally, an optimal current controller is developed using MPC techniques that allows the optimal utilization of the system’s torque capability under electrical limitations. Simulation results and experimental validations are obtained to corroborate the initial approaches, through the use of particular cases of five-phase drives controlled using different frequency-domain control subspaces.

Page generated in 0.0875 seconds