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Miranda, Quispe Bruno Sebastian. "Diseño conceptual de un pie protésico que permite determinar las fuerzas de contacto pie-piso sobre pendientes, escalones y superficies con irregularidades durante la marcha." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2020. http://hdl.handle.net/20.500.12404/19471.
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El presente documento se basa en una investigación para realizar un monitoreo correcto de fuerzas de contacto pie-piso a usuarios con prótesis de miembro inferior; pues, se ha demostrado, que los pacientes presentan condiciones degenerativas en la columna baja y cadera al no tener una carga homogénea de contacto. Por tal motivo, este trabajo tiene como objetivo realizar el diseño conceptual de un pie protésico que detecte las fuerzas pie-piso sobre pendientes, escaleras y superficies irregulares durante la marcha. Esta investigación se basa en realizar un estudio de la Biomecánica del pie, y el Estado de la Tecnología donde se busca modelos comerciales de pies protésicos dinámicos por su adaptabilidad en las superficies y las tecnologías existentes de sensado con el fin de poder adaptar ambas cualidades en una sola prótesis. El funcionamiento conceptual del pie consiste en moldearse a la superficie de contacto, una vez hecho eso, los sensores de carga brindan la información de las fuerzas y por medio de un sensor inercial se obtiene la dirección de estas cargas de contacto. Se obtienen tres conceptos de solución que son verificados por una evaluación técnica económica y se obtiene un concepto óptimo basado en los resultados. Este concepto óptimo cuenta con sensores en la planta del pie y es dinámico para pisar correctamente las superficies mencionadas. En adición, este proyecto es importante porque brinda información sobre las reacciones de contacto que tiene el pie durante la caminata y permite acceder a mayores alcances sobre la biomecánica de la rehabilitación y marcha humana.Trabajo de investigación
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Yoo, Doo-Sung. "Organ-machine Hybrids (Artificial Animals)." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281418915.
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Ariss, Joseph, and Salim Rabat. "A comparison between a traditional PID controller and an Artificial Neural Network controller in manipulating a robotic arm." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-259365.
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Robotic and control industry implements different control technique to control the movement and the position of a robotic arm. PID controllers are the most used controllers in the robotics and control industry because of its simplicity and easy implementation. However, PIDs’ performance suffers under noisy environments. In this research, a controller based on Artificial Neural Networks (ANN) called the model reference controller is examined to replace traditional PID controllers to control the position of a robotic arm in a noisy environment. Simulations and implementations of both controllers were carried out in MATLAB. The training of the ANN was also done in MATLAB using the Supervised Learning (SL) model and Levenberg-Marquardt backpropagation algorithm. Results shows that the ANN implementation performs better than traditional PID controllers in noisy environments.Robotoch kontrollindustrin implementerar olika kontrolltekniker för att styra rörelsen och placeringen av en robotarm. PID-styrenheter är de mest använda kontrollerna inom roboten och kontrollindustrin på grund av dess enkelhet och lätt implementering. PID:s prestanda lider emellertid i bullriga miljöer. I denna undersökning undersöks en styrenhet baserad på Artificiell Neuralt Nätverk (ANN) som kallas modellreferenskontrollen för att ersätta traditionella PID-kontroller för att styra en robotarm i bullriga miljöer. Simuleringar och implementeringar av båda kontrollerna utfördes i MATLAB. Utbildningen av ANN:et gjordes också i MATLAB med hjälp av Supervised Learning (SL) -modellen och LevenbergMarquardt backpropagationsalgoritmen. Resultat visar att ANN-implementeringen fungerar bättre än traditionella PID-kontroller i bullriga miljöer.
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Yin, Choon Meng. "Application of artificial neural networks to condition monitoring." Thesis, University of Aberdeen, 1993. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=124315.
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Predictive maintenance or condition-based maintenance offers significant advantages over the traditional methods of preventive or breakdown maintenance of electromechanical systems. Despite its benefits, predictive maintenance is difficult to implement. This has led to the development of various techniques which allow the early detection of many common fault conditions, through analysis of quantities such as spectral components of line currents, magnetic fields and frame vibrations. Associating the observed signal patterns with the condition of the machine depends to a great extent on the experience and knowledge of experts. The fact that human operators are very successful at these monitoring tasks suggests that one possible method for designing computer-based monitoring systems is to model the learning and decision-making abilities of a human operator. The philosophy pursued in this research is therefore to design a system that should be able to emulate as closely as possible the learning, pattern recognition and the sensor fusion abilities of human operators. This thesis is, therefore, concerned with the application of artificial neural networks to condition monitoring of electrical drives, with particular reference to induction motors. The neural networks studied were the multi-layered perceptron (MLP) and the Kohonen self-organising feature map (KFM). The learning paradigm of the former is supervised, while the latter is unsupervised. A comprehensive theoretical basis is provided for both neural networks employed, and their effectiveness is verified by suitable experiments. The ability of the neural networks to predict the condition of the machine for varying fault severity as well as the transferrability of a trained network to monitor other machines of similar characteristics were also of interest. The suitability of the neural network fault diagnosis system for inverter-fed machines was also studied.
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Schöne, Pia [Verfasser], Ludger [Gutachter] Wessjohann, and Ewa [Gutachter] Swieżewska. "Enzymatic synthesis of natural and artificial polyprenols / Pia Schöne ; Gutachter: Ludger Wessjohann, Ewa Swieżewska." Halle (Saale) : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2019. http://d-nb.info/121073138X/34.
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Starkey, Andrew J. "Condition monitoring of ground anchorages using artificial intelligence techniques." Thesis, University of Aberdeen, 2001. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=217212.
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Neural networks are a form of Artificial Intelligence based on the architecture of the human brain. They allow complicated non-linear relationships to be learnt from example data, and for further test data to be identified according to the relationship previously learnt. This allows the construction of control systems and diagnostic systems of geotechnical processes which were previously not possible due to their complicated non-linear nature. The main topic of research is the application of neural networks to the diagnosis of the condition of ground anchorages. Ground anchorages are in use in many engineering structures such as tunnels, retaining walls and dams and it has been reported that only 5-10% are routinely monitored during service. The conventional method of testing is load lift-off testing, which is expensive and time consuming. The patented technique, GRANIT, makes use of neural networks to learn the complicated relationship between the vibrational response of an anchorage to an applied axial impulse and its post-tension level. Research has been conducted into the parameters of the system which affect the diagnostic ability of the neural network. Further research into the application of the GRANIT technique to the identification of other faults in the anchorage has been conducted, such as change in free length, or gaps in the grouting. An automated procedure for the identification of the frequencies of interest in the response signatures of the GRANIT system has been investigated, and an example is given of an application of this automated procedure in the area of vibro-impact ground moling, a patented technique which uses both vibration and impact to maximise its penetration depth. Further research into the use of neural networks in an automated process has also been undertaken, and the development of a new technique is presented. This new technique has the potential of returning parameters of interest from any given group of signals, and has potential of application outwith geotechnical data. A patent application for this new technique has now been filed by the author.
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Santos, Hilton Seheris da Silva. "Sintonia online de controladores PID adaptativo-ótimo via redes neuronais artificiais." Universidade Federal do Maranhão, 2017. http://tedebc.ufma.br:8080/jspui/handle/tede/1743.
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The emergence of new industrial plants with great complexity and the need to improve the operation of existing plants has fostered the development of high performance control systems, these systems must not only meet the design specifications, such as merit figures, but also operate at minimal cost and impacts at environment. Motivated by this demand, it is presented in this dissertation the development of methods for on-line tuning of control system parameters, ie, a methodology is presented for the on-line tuning of adaptive and optimal PID controllers via Artificial Neural Networks(ANNs). The approach developed in this dissertation is based on three PID controllers parameters. [Artificial neural networks with radial base functions and Model Predictive Control (MPC). From the union of these approaches a general formulation of an Adaptive-optimal PID controller via artificial neural networks with on-line tuning was presented. The on-line tuning methodology for the ANN parameters is presented in the context of MPC, predicting plant output. For the PID controller, we proposed a modification of the standard structure in order to adapt the error function. The adjustment of the PID controller parameters and the prediction of the optimally plant output, are performed by the ANN-RBF weights adjustments. In addition, an indoor implementation of the control system were proposed for the positioning of a photovoltaic panel. The performance evaluations of the proposed system were obtained from computational experiments results that were based on mathematical models and hardware experiments, that were obtained from a reduced model of a photovoltaic panel. Finally, a comparison between the proposed methodology with the classical PID controller were performed and the proposed methodology presented to be more flexible to the insertion of new performance metrics and the results achieved from the ANN, were better than the ones obtained by the classical PID tuning, such as: Ziegler-Nichols or trial and error.
O surgimento de novas plantas industriais com grande complexidade e a necessidade de melhorar a operação das plantas já existentes tem fomentado o desenvolvimento de sistemas de controle de alto desempenho, estes sistemas devem atender não só as especificações de projeto, tal como: figuras de mérito, mas também devem operar com um custo mínimo e sem causar impactos desastrosos para o meio ambiente. Motivados por esta demanda, apresenta-se nesta dissertação o desenvolvimento de métodos para sintonia online dos parâmetros dos sistemas de controle, ie, apresenta-se uma metodologia para a sintonia online de controladores PID adaptativo e ótimo via Redes Neurais Artificiais (RNAs). A abordagem desenvolvida nesta dissertação tem base as ações dos controladores PID de três termos, redes neurais artificiais com funções de base radial e Controle preditivo baseado em modelo (MPC - Model Predictive Control), a partir da união destas abordagens elabora-se a formulação geral do controlador PID Adaptativo-Ótimo via redes neurais artificiais, com sintonia online. A metodologia de ajuste online dos parâmetros da RNA está no contexto do MPC para predição de saída da planta. Para o caso do controlador PID, tem-se a modificação da estrutura padrão com o objetivo de adaptação em função do erro. O ajuste dos termos do controlador PID e da predição da saída na planta, de forma ótima, é realizada pelo ajustes dos pesos da RNA-RBF. Além disso, apresenta-se a implementação indoor do sistema de controle desenvolvido para o posicionamento de um painel fotovoltaico. As avaliações de desempenho do sistema proposto são obtidos de resultados de experimentos computacionais que são baseados em modelos matemáticos e experimentos em hardware que são obtidos de um modelo reduzido de um painel fotovoltaico. Por fim, comparando o PID clássico com o controlador desenvolvido constatou-se que este último apresenta mais flexibilidade para inserir novas métricas de desempenho e os resultados atingidos são melhores do que os parâmetros obtidos por meio da sintonia do PID clássica, tais como: métodos de Ziegler-Nichols ou tentativa e erro
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Ara?jo, Renan Pires de. "Modelagem da velocidade de um PIG instrumentado usando redes neurais artificiais." PROGRAMA DE P?S-GRADUA??O EM CI?NCIA E ENGENHARIA DE PETR?LEO, 2017. https://repositorio.ufrn.br/jspui/handle/123456789/23718.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
A passagem de um PIG ? uma t?cnica bastante empregada na inspe??o de dutos de longo comprimento e principalmente enterrados, valendo-se do diferencial de press?o sobre o mesmo para impulsion?-lo. Por?m, durante a inspe??o, um dos problemas que pode ocorrer ? a parada do PIG por causa de incrusta??es severas ou defeitos de fabrica??o/instala??o dos dutos, fazendo com que o instrumento pare e sua posterior libera??o com altas velocidades devido ao ac?mulo de press?o ? montante. Este trabalho prop?e o uso de redes neurais artificiais a fim de modelar a rela??o entre o diferencial de press?o sobre o PIG e sua velocidade durante o seu trajeto no interior do duto. Para tanto, foi empregado um sistema supervis?rio para a captura dos dados de press?o ao longo da tubula??o de teste e um od?metro acoplado ao PIG para a dos dados de velocidade. Foram considerados dois modelos de redes neurais artificiais, no caso a rede MLP e a rede NARX, sendo esta ?ltima uma rede recursiva. Os resultados de treinamento e valida??o mostraram que os modelos por redes neurais artificiais foram eficientes para estimar a velocidade do PIG.
The passage of a PIG is a technique quite used in inspection of big length and principally buried pipes using the pressure differential on it to impulse itself. But, during the inspection, one of the problems that may occur is the stop of the PIG because of severe incrustations or fabrication/installation defects of the pipes, doing the halt of the instrument and its posterior release with high velocities due to the accumulate of pressure at back part. This work purpose the use of neural networks in order to model the relation between the differential pressure on the PIG and its velocity during your path in the tube. Therefore, it was used a supervisory system to capture the pressure data along the test pipe and an odometer coupled to the PIG for the velocity data. It was considered two neural network models, in the case the MLP and NARX networks, the latter being a recurrent network. The training and validation results showed that the models by neural networks were efficient to estimate the velocity of the PIG.
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SILVA, Jeydson Lopes da. "Controle eficiente com ferramentas de inteligência artificial em um sistema de exaustão." Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/24927.
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FACEPE
A energia elétrica é considerada como um dos principais insumos do setor industrial; sua disponibilidade, qualidade e custo são diretamente ligados à capacidade competitiva deste setor. Com o aumento dos custos da eletricidade e da emissão de gases causadores do efeito estufa, ações voltadas para o uso eficiente deste insumo tornam-se cada vez mais atrativas. Uma parte muito importante da área de controle e automação dos processos industriais é a sintonia dos controladores PID, uma vez que os processos, dentre outras coisas, dependem dos seus controladores, e estes para serem produtivos precisam estar bem sintonizados. O presente trabalho descreve uma maneira de sintonizar desses tipos de controladores baseada em inteligência artificial utilizando uma técnica de otimização evolutiva, conhecida como Otimização por Enxame de Partícula (PSO), técnica eficiente na otimização de funções com vários mínimos locais, funcionando desta forma como uma alternativa às diversas formas de sintonizações clássicas existentes. O objetivo deste trabalho é o de demonstrar o ganho em desempenho no controlador, tanto na parte energética como na ação de controle, proporcionado pela sintonia do controlador através do PSO. Uma parte importante da metodologia deste trabalho é a possibilidade da implementação direta no sistema real dos parâmetros sintonizados do controlador, encontrados por meio da otimização por PSO via simulação computacional; para isso, foi necessária a modelagem do sistema de forma digital, a qual permitiu reproduzir os efeitos da dinâmica do processo real. A implementação real foi feita por meio do protótipo de um sistema de exaustão industrial, o qual é todo controlado por um controlador lógico programável (CLP), localizado no Laboratório de Sistemas Motrizes da Universidade Federal de Pernambuco, a partir do qual foi realizada a coleta de dados experimentais para a análise do desempenho do sistema quando do uso deste tipo de sintonia do controlador.
Electricity is considered as one of the main inputs of the industrial sector; its availability, quality and cost are directly related to the competitive capacity of this sector. With rising costs of electricity and the emission of greenhouse gases, actions aimed at the efficient use of this input become increasingly attractive. A very important part of the area of control and automation of industrial processes is the tuning of the parameters of the PID controllers, since the processes, among other things, depend on their controllers, and these to be productive must be well tuned. The present work describes a way of tuning these types of controllers based on artificial intelligence using an evolutionary optimization technique, known as Particle Swarm Optimization (PSO), an efficient technique for optimizing functions with several local minimums, working in this way as a different form of classical tuning. The objective of this work is to demonstrate the gain in performance in the controller, both in the energy part and in the control action, provided by the controller tuning through the PSO. An important part of the methodology of this work is the possibility of directly implementing in the real system the tuned parameters of the controller, found by means of PSO optimization through computational simulation; for this it was necessary to model the system in digital form, which allowed to reproduce the effects of the actual process dynamics. The actual implementation was done through the prototype of an industrial exhaust system, which is all controlled by means of a PLC, located in the Laboratory of Motor Systems of the Federal University of Pernambuco, from which the collection of experimental data for the analysis of the performance of the system when using this type of controller tuning.
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Souza, João Olegário de Oliveira de. "Metaheurísticas aplicadas na sintonia de controladores PID: estudo de casos." Universidade do Vale do Rio dos Sinos, 2013. http://www.repositorio.jesuita.org.br/handle/UNISINOS/4457.
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Nenhuma
Os controladores do tipo Proporcional, Integral e Derivativo, comumente denominados de PID, são largamente utilizados no controle de processos industriais, tanto em sistemas monovariáveis quanto em sistemas multivariáveis. Hoje, cerca de 95% dos controladores utilizam este tipo de estrutura na indústria. O grande problema é que grande parte deles estão mal sintonizados, comprometendo em muitos casos o desempenho de malhas industriais. Neste trabalho é apresentada uma revisão geral sobre os algoritmos inspirados na natureza, Simulated Annealing e Algoritmos Genéticos (fundamentos, características, parâmetros, operadores) e sua aplicação ao problema da sintonia de controladores PID monovariáveis e multivariáveis. É estabelecida, através de estudo de casos, uma análise comparativa entre estas sintonizações com metaheurísticas e os métodos consagrados na literatura em aplicações industriais convencionais, utilizando como função de avaliação o índice Integral do Erro Absoluto ponderado pelo Tempo (ITAE). O trabalho também propõe o estudo de controladores PID através de Algoritmos Genéticos Multiobjetivos, que satisfaçam dois critérios de desempenho: overshoot e o índice de desempenho Integral do Erro Quadrático ponderado pelo Tempo (ITSE). Conforme demonstrado pelos resultados obtidos, pode-se afirmar que a metaheurística Algoritmos Genéticos é um método eficiente e confiável para a otimização de problemas de sintonia de controladores PID.
The Proportional, Integral and Derivative controllers, commonly called PID controllers, are widely used in industrial process control, in both SISO and multivariable systems. Today about 95% of controllers use this type of structure in the industry. The big problem is that most of them are poorly tuned, in many cases compromising the performance of industrial loops. This work presents a general review on nature-inspired algorithms, Simulated Annealing and Genetic Algorithms (basement, characteristics, parameters, operators) and its application in the problem of tuning PID controllers in both single variable and multivariable systems. There will be through case studies, a comparative analysis of these metaheuristics with established methods in the literature in conventional industrial applications using as evaluation function the Integral of time multiplied by the Absolute Error (ITAE) index. The work also proposes the study of PID controllers using multiobjective genetic algorithms which meet two performance criteria: overshoot and the Integral Time Square Error (ITSE) index. The results obtained confirm that Genetic Algorithms are an effective and reliable method to optimize complex problems.
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Corneillie, Todd Matthew. "Converting weak binders into infinite binders : irreversible engineering of an artificial receptor for pretargeted imaging and therapy /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.
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Masato, Daniele. "Incremental activity and plan recognition for human teams." Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=186768.
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Anticipating human subjects' intentions and information needs is considered one of the ultimate goals of Artificial Intelligence. Activity and plan recognition contribute to this goal by studying how low-level observations about subjects and the environment in which they act can be linked to a high-level plan representation. This task is challenging in a dynamic and uncertain environment; the environment may change while the subjects are reasoning about it, and the effects of the subjects' interactions cannot be predicted with certainty. Humans generally struggle to enact plans and maintain situation awareness in such circumstances, even when they work in teams towards a common objective. Intelligent software assistants can support human teams by monitoring their activities and plan progress, thus relieving them from some of the cognitive burden they experience. The assistants' design needs to keep into account that teams can form and disband quickly in response to environmental changes, and that the course of action may change during plan execution. It is also crucial to efficiently and incrementally process a stream of observations in order to enable online prediction of those intentions and information needs. In this thesis we propose an incremental approach for team composition and activity recognition based on probabilistic graphical models. We show that this model can successfully learn team formations and behaviours in highly dynamic domains, and that classification can be performed in polynomial time. We evaluate our model within a simulated scenario provided by an open-source computer game. In addition, we discuss an incremental approach to plan recognition that exploits the results yielded by activity recognition to assess a team's course of action. We show how this model can account for incomplete or inconsistent knowledge about recognised activities, and how it can be integrated into an existing mechanism for plan recognition.
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Nguyen, Van Bac. "Numerical modelling of reinforced concrete bridge pier under artificially generated earthquake time-histories." Thesis, University of Birmingham, 2006. http://etheses.bham.ac.uk//id/eprint/25/.
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A number of artificially generated earthquake time-histories (AGETH) fitting to a Eurocode 8 (EC8) response spectrum are randomly generated using SIMQKE software and the average generated spectrum compares well with the EC8 one. Two Finite element (FE) smeared crack models, named Multi-crack and Craft, are well validated against experimental data of concrete and Reinforced concrete (RC) structures under monotonic and cyclic loadings. They are then used in the analysis of RC bridge piers under the AGETH. Several techniques including Fourier analysis, normalised cumulative spectrum, energy dissipation, damage index as well as probability applications are applied to quantify the structural response and damage. Based on the convergence of the representative responses under different numbers of AGETH, a minimum representative number of AGETH from 6 to 11 may be sufficient depending on the confidence band width from the mean of all damage responses. Effects of several parameters of the earthquake and structure to the dynamic response and damage of the bridge pier are investigated. Throughout these parametric studies, several of the common circumstances that structural engineers face are addressed and the proposed number of artificial earthquake time-histories required for non-linear dynamic analysis is thereby validated.
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Barter, Garrett E. (Garrett Ehud) 1979. "Shock capturing with PDE-based artificial viscosity for an adaptive, higher-order discontinuous Galerkin finite element method." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44931.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2008.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 135-143).
The accurate simulation of supersonic and hypersonic flows is well suited to higher-order (p > 1), adaptive computational fluid dynamics (CFD). Since these cases involve flow velocities greater than the speed of sound, an appropriate shock capturing for higher-order, adaptive methods is necessary. Artificial viscosity can be combined with a higher-order discontinuous Galerkin finite element discretization to resolve a shock layer within a single cell. However, when a nonsmooth artificial viscosity model is employed with an otherwise higher-order approximation, element-to-element variations induce oscillations in state gradients and pollute the downstream flow. To alleviate these difficulties, this work proposes a new, higher-order, state based artificial viscosity with an associated governing partial differential equation (PDE). In the governing PDE, the shock sensor acts as a forcing term, driving the artificial viscosity to a non-zero value where it is necessary. The decay rate of the higher-order solution modes and edge-based jumps are both shown to be reliable shock indicators. This new approach leads to a smooth, higher-order representation of the artificial viscosity that evolves in time with the solution. For applications involving the Navier-Stokes equations, an artificial dissipation operator that preserves total enthalpy is introduced. The combination of higher-order, PDE-based artificial viscosity and enthalpy-preserving dissipation operator is shown to overcome the disadvantages of the non-smooth artificial viscosity. The PDE-based artificial viscosity can be used in conjunction with an automated grid adaptation framework that minimizes the error of an output functional. Higher-order solutions are shown to reach strict engineering tolerances with fewer degrees of freedom.
(cont.) The benefit in computational efficiency for higher-order solutions is less dramatic in the vicinity of the shock where errors scale with O(h/p). This includes the near-field pressure signals necessary for sonic boom prediction. When applied to heat transfer prediction on unstructured meshes in hypersonic flows, the PDE-based artificial viscosity is less susceptible to errors introduced by poor shock-grid alignment. Surface heating can also drive the output-based grid adaptation framework to arrive at the same heat transfer distribution as a well-designed structured mesh.
by Garrett Ehud Barter.
Ph.D.
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Goerrissen, Jan. "Grassland birds in California : an investigation into the influence of season, floristic composition, and artificial structures on avian community structure /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.
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Thesis (Ph. D.)--University of California, Davis, 2005."June 2005"--Leaf 1. Degree granted in Ecology. Includes bibliographical references. Also available via the World Wide Web. (Restricted to UC campuses)
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Kroscher, Kellie Ann. "Nutritional Strategies to Improve Pig Growth and Performance." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/100306.
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Many factors influence the efficiency of muscle growth including genetics, nutrition, and environment. The neonatal period is characterized as a time of rapid growth. Growth rate is reduced during neonatal nutrient restriction possibly due to altered satellite cell activity which can permanently alter growth potential. Therefore, optimal nutrition is important for maximizing the growth potential of the animal. Heat stress leads to changes in digestion and metabolism, thus alters nutrient availability to muscle. Heat stress is a prevalent problem in the agriculture industry resulting in great economic losses due to reduced growth, fertility, and increased morbidity. The use of functional feed additives is a potential strategy to mitigate these negative effects. The objective of this dissertation was to investigate nutritional strategies to improve growth in pigs during key malleable periods. Three nutritional studies were conducted to discern the optimal inclusion levels of calcium phosphate, energy, and protein in the diet to maximize neonatal muscle growth. Adequate dietary calcium phosphate was most efficient for satellite cell function which may be mediated by micro-RNA. Differentiation promoting miR-206 and correspondingly the fusion rate was highest in adequate calcium phosphate diets. Excess protein diets enhanced body and muscle growth, while deficient protein was detrimental to growth. Dietary protein treatments altered energy metabolism genes, and genes regulating protein degradation were upregulated in deficient protein diets. Dietary energy levels did not influence body weight, however feed efficiency improved with energy balance. Excess energy diets had the lowest fusion rates and the lowest differentiation promoting miR-1 expression. These data suggest that nutrient inclusion levels are important for satellite cell function and may mediate satellite cell activity through the expression of micro-RNAs. The final study sought to discern the ability of supplementation of an artificial high-intensity sweetener and capsicum oleoresin to mitigate the negative effects of heat stress on pig performance. Heat stress leads to increased body temperature and respiration and was detrimental to metabolic flexibility. Supplementation helped improve feed efficiency and maintain metabolic flexibility. These data indicate that supplementation may be an efficient strategy to mitigate heat stress.Doctor of Philosophy
Muscle is an important tissue to consider when optimizing growing conditions in feed animals due to its function as a consumer good. Many factors influence the efficiency of muscle growth including genetics, nutrition, and environment. Fractional growth rates are highest during the neonatal period and animals require adequate nutrients to facilitate this growth. Nutrient restriction reduces growth rate and can lead to permanent changes the animals' body size and composition later in life. Therefore, optimal nutrition is important for maximizing the growth potential of the animal. While the nutrients in feed can be controlled to improve growth, other factors are more difficult to regulate. Heat stress is a prevalent problem in the agriculture industry resulting in great economic losses due to reduced growth, fertility, and increased morbidity. The use of functional feed additives is a potential strategy to alleviate these negative effects. The objective of this dissertation was to investigate nutritional strategies to improve growth in pigs during key malleable periods. Three nutritional studies were conducted to determine the optimal inclusion levels of calcium phosphate, energy, and protein in the diet to maximize neonatal muscle growth. Satellite cells are muscle-specific stem cells that help facilitate the growth of muscle. Altering the ability of satellite cells to proliferate and fuse impairs the ability of muscle to grow and repair. Adequate dietary calcium phosphate was most efficient for satellite cell function. Excess protein diets enhanced body and muscle growth, while deficient protein was detrimental to growth. Dietary protein treatments altered energy metabolism genes, and genes regulating protein degradation were upregulated in deficient protein diets. Dietary energy levels did not influence body weight, however, feed efficiency improved with energy balance. Satellite cells from excess energy diets had the lowest fusion rates. These data suggest that nutrient inclusion levels are important for satellite cell function and growth. The final study sought to discern the ability of the supplementation of an artificial high-intensity sweetener and capsicum oleoresin to mitigate the negative effects of heat stress on pig performance. Heat stress leads to increased body temperature and respiration and was detrimental to metabolic flexibility. Supplementation helped improve feed efficiency and maintain metabolic flexibility. These data indicate that supplementation may be an efficient strategy to mitigate heat stress.
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Rouse, Sally. "Quantifying benthic secondary productivity on artificial structures : maximising the benefit of marine renewable energy devices." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231790.
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Marine renewable energy developments (MRED) will result in large quantities of infrastructure being deployed in coastal habitats, and the localised exclusion of fishing. The ecological consequences of this scale of deployment are largely unknown, particularly for benthic species. Infrastructure has the capacity to act as artificial reefs (ARs), providing novel habitat, and this may viewed as a benefit of MRED, or a means to mitigate the exclusion of fishing. At present, the functioning of AR ecosystems remains poorly understood. As a measure of ecosystem function, secondary productivity can be used to assess the implications of MRED. The lack of suitable methodology, deployable at relevant scales within time and/or cost constraints, has limited benthic secondary productivity (BSP) quantifications on ARs. Techniques to measure potential BSP and particle flux were developed and applied to the Loch Linnhe Artificial Reef (functionally similar to scour protection material). Variations in BSP and mobile epifaunal densities on, and between, structures in different environments were quantified. Reefs exposed to intermediate current had the highest potential productivity. The BSP on internal areas of structures contributed to the total productive output, but the relative contribution varied according to reef location and design. BSP was primarily determined by particle supply, but the response was not consistent among locations. Mobile epifaunal densities related to reef location, but not reef design, and were highest on reefs in the deepest water and exposed to the fastest currents. The evidence presented in this thesis highlights the need to account for the receiving environment when predicting the ecological consequences of MRED, or when modelling the productive capacity of structures. Such information can be used to suggest modifications to proposed or existing structures in order to maximise their benefit to coastal ecosystems.
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Okoliegbe, Ijeoma Nnenna. "Longitudinal investigation of mixed-species biofilm formation and its effect on device longevity in patients using voice prostheses." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=236942.
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In the UK, there are up to 3,000 cancer patients who have undergone total laryngectomy and use voice prostheses (VPs), for speech rehabilitation. VPs are inserted between the eosphagus and trachea to provide a 'voice' but, as with other semi-in-dwelling devices, such as nasal and gastric tubes, they invariably fail due to occlusion by microbial biofilms. The requirement for frequent replacement is financially costly to the NHS and impacts patient well-being. Replacement frequency varies by patient, from 7 weeks to 6 months but the reasons for this variation are not clearly understood. By designing and implementing a study of microbial colonisation of VPs and oral rinse samples submitted by 14 Speech and Voice Clinic patients over 13 months, this study explored whether specific microbes or patient factors, including the use of antacids, antibiotics and nystatin, along with denture-use, were potential predictors of device longevity. Focussing on the role of the commonly isolated fungi, we sought to understand the role of diet or the presence of the bacterium, S. aureus, in biomass accumulation. We also asked whether biofilm regulation pathways are shared across the fungi and could constitute a potential target for therapeutics. Microbial isolation from 66 VPs showed the predominant species as described in previous studies, but each participant had a unique profile which persisted over time, with half of the microbes originating from the oral flora. Clinic-based participants experienced fewer problems, primarily due to the device type used, and carried fewer species of Gram negative bacteria than the long term users. Statistical analysis showed that patient medication influences biofilm composition and dietary sugars differentially affect biomass formation. In vitro experiments showed that the ability to treat Candida biofilms with nystatin was improved in the presence of S. aureus. Expression analysis showed that regulation of biofilms in C. parapsilosis was the closest to that of C. albicans but that the extent of protein homology to C. albicans regulators was not a predictor of expression levels. It is therefore unlikely that a single therapeutic could be developed to target biofilm gene regulation. This work provides new insights into the complexity of biofilm formation in voice prosthesis users but reveals associations between microbes, diet, prosthesis type and medications that might be used to advise patients and help to reduce the stress and cost of frequent device failure and replacement.
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Venegas, Flores Dulce Charin. "Sistema para pre-diagnóstico de cáncer de melanomas usando redes neuronales artificiales." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2019. http://hdl.handle.net/20.500.11799/99685.
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Se propone el desarrollo de un sistema de pre-diagnóstico para cáncer de piel, que se delimitara específicamente en lunares (médicamente conocido como melanomas). El sistema se formara con un algoritmo de Redes neuronales artificiales, obteniendo una respuesta elevada en la predicción, en base a la colección de imágenes almacenadas, donde serán clasificadas según su carácter (como benigno o maligno). Ya que, las redes neuronales seleccionan y otorgan el pre-diagnóstico resultando como positivo o negativo.
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Dunne, John H. "A study of factors influencing reproductive efficiency in the pig with particular emphasis on the role of artificial insemination." Thesis, University of Aberdeen, 1995. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU079021.
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Three studies were conducted on commercial farms. Study 1 sought to compare four combinations of natural mating (NM) and AI, namely AI + AI, AI + NM, NM + AI and NM + NM (first mating on day 1 of oestrous and second on day 2), and evaluate what aspects of insemination quality are related to fertility. The respective farrowing rates (FR) of AI + AI, AI + NS, NS + AI and NS + NS were (number of sows in parentheses) 92.9% (141), 89.6% (134), 89.3% (140) and 89.0% (100) and litter size (LS) was 11.31, 10.49, 11.50 and 10.61 (total births). The number of pigs born per 100 sows mated were 1051, 940, 1027 and 944. Both FR (P < 0.05) and LS (P < 0.01) were significantly influenced by parity. Sow behaviour during insemination significantly influenced (P < 0.01) FR and LS, the mean FR of calm and agitated sows being 91.3 and 83.1 percent and the mean LS being 11.32 and 10.22 respectively. Loss of semen due to backflow during insemination significantly reduced (P < 0.05) FR in sows having one AI. Backflow losses were significantly lower (P < 0.01) in calm than in agitated sows. It was concluded that AI, either alone or in combination with NM, yields fertility results comparable to NM alone and that sow behaviour during insemination has an important effect on sow fertility. Study 2 tested the effect of the addition of 5 i.u. of oxytocin to semen immediately before AI on fertility at two farms. Overall oxytoxin significantly improved FR (P < 0.05) from 73.2 percent (429) to 79.5 percent (385) and substantially improved litter size from 10.70 to 11.18. There was a significant (P < 0.05) treatment x farm interaction, FR on farm A improving from 77.2% (control) to 78.0% (oxytocin) whereas FR on farm B improved from 69.7% (control) to 84.0% (oxytocin). It was hypothesised that differences between farms in operator skill during insemination may have mediated the differing response to oxytocin.
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Rangel, Cortes Juan José. "Sistema para pre-diagnosticar el cáncer de piel tipo melanoma." Tesis de maestría, Universidad Autónoma del Estado de México, 2019. http://hdl.handle.net/20.500.11799/105224.
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El cáncer de piel más común es el de tipo melanoma. Dicho cáncer, ha aumentado en
múltiples partes del mundo. Por lo anterior, se trabajó en la clasificación de melanomas para
apoyar la posible detección de melanomas malignos que causan cáncer de piel. Se utilizaron
redes neuronales convolucionales o (CNN) por sus siglas en inglés, para la clasificación de
los melanomas en malignos o benignos. Se utilizaron imágenes disponibles de International
Skin Imaging Collaboration (ISIC). Se aplicaron cuatro técnicas: 1) Se clasificaron
melanomas añadiendo metadatos de edad, género y tamaño del melanoma, dentro de la
misma matriz de pixeles. 2) Se procesaron las imágenes quitando la piel de la lesión. 3) Se
aplicó la CNN con un tamaño de 300 x 300 pixeles y con 2000 imágenes. 4) Se aplica la CNN
disminuyendo el tamaño de las imágenes (100x100 pixeles) y se aumentaran las épocas hasta
1000. Se llevó a cabo el entrenamiento y validación en cada técnica. Al final, se probó cada
técnica con imágenes nuevas no usadas en el entrenamiento ni validación y se obtuvieron
resultados. En los resultados, se obtuvo un mejor resultado en la cuarta técnica cuando se
añadieron más épocas.
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Chizari, Mahmoud. "The mechanical study of double-tunnel-double-bundle anterior cruciate ligament reconstructive surgery : graft and tibial/femoral channel performance." Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=167333.
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This is an interdisciplinary research project in which the methods of biomechanical and design engineering are focused upon a problem in orthopaedics. The anterior cruciate ligament (ACL) is the major ligament in the knee and is often torn during athletic competition as well as every day activity. The ACL is made up of two functional bundles, which help to stabilize the knee. Until recently, ACL reconstruction only replaced one of these bundles; however, research shows that both bundles should be replaced to more fully restore normal knee functionality. The aim of the research was, therefore, to evaluate the mechanical aspects of the double-tunnel-double-bundle ACL reconstruction technique. The research was directed towards designing a new and improved surgical device to improve ACL reconstruction: The current study used a computational model and experimental testing to explore the mechanical parameters of the tendon graft and knee bones to investigate the effects of double tunnel drilling in tibia and femur during ACL reconstruction. The thesis presents the findings of research into three aspects of double-tunnel-double-bundle ACL reconstruction. The first aspect of the study involves clinical and computational analysis of a single-tunnel-singlebundle (SB) ACL reconstructed knee with a double-tunnel-double-bundle (DB) ACL reconstructed example. The study tried to show the advantage of the DB technique over the conventional SB technique. The anatomical geometries of both SB and DB examples were used to create a finite element model and investigate the relative merits of single and double tunnelling, the variations of graft pretension, and tunnel placement on bone stress. The experimental and computational results of both methods were compared and discussed. The second study investigated whether tripling a tendon when using suspensory fixation provides inferior graft strength and a greater cyclical elongation than a doubled tendon graft with suspensory fixation. The tensile stress was found to be lower in the third strand than in the doubled portion. The study was focussed on the mechanical assessment of two different methods of tripling tendons when using suspensory fixation. The third aspect of the study focussed on the design of a new device for fixation of the femoral tripled tendon graft in DB ACL reconstruction technique. The study describes a series of designs and prototypes that were iteratively developed and experimentally tested, leading to a novel tripled tendon graft device. The function of the new device was compared with the conventional methods and tested with a number of animal tendons and bones. The new device with a tripled tendon graft resulted in higher pull-out strength and less graft elongation than that seen using a conventional tripling method.
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Hossain, Ziaul. "A study of mechanisms to support variable-rate Internet applications over a multi-service satellite platform." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225781.
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Satellite broadband has the potential to provide Internet connectivity to people and places that are unreachable using other wired/wireless technologies. It is therefore a critical component of any service seeking to provide universal coverage. A universal service needs to support a range of Internet applications. While there is existing work on bulk and interactive applications with a characteristic transmission rate, popular Internet applications such as web browsing, web video download or variable-rate voice result in a network traffic that varies its transmission rate. This thesis first investigates the interaction of satellite resource request mechanisms with the quality of service offered to these variable-rate applications using a satellite platform based on DVB-RCS2. It shows that a flexible QoS architecture can be achieved by a combination of resource request methods and network-layer queuing. Variable-rate traffic also poses challenges to the widely deployed Transport Control Protocol (TCP). Previous work analysed the interaction with the congestion control algorithms and proposed Congestion Window Validation (CWV) to constrain the congestion window to the amount of traffic a transport has sent. TCP JAGO studied this problem for variable-rate bursty applications and proposed new algorithms; but these were shown to have drawbacks and there were no guidance on how to implement. This thesis therefore presents, newCWV, a practical mechanism to provide an appropriate estimate of the available path capacity and corresponding congestion control behaviour. This benefits variable-rate applications with shorter transfer durations, but has a consequence of allowing larger traffic bursts into the network that can increase packet loss. Burst mitigation techniques, such as TCP pacing, are proposed to deal with this. These techniques are implemented and tested in the Linux TCP/IP stack, where newCWV improves the burst transfer time. This benefit is particularly significant for the large delay of broadband satellite systems.
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Ingram, Stephen D. "Visual Feedback Stabilisation of a Cart Inverted Pendulum A." Thesis, University of Bradford, 2016. http://hdl.handle.net/10454/17375.
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Vision-based object stabilisation is an exciting and challenging area of research, and is one that promises great technical advancements in the field of computer vision. As humans, we are capable of a tremendous array of skilful interactions, particularly when balancing unstable objects that have complex, non-linear dynamics. These complex dynamics impose a difficult control problem, since the object must be stabilised through collaboration between applied forces and vision-based feedback. To coordinate our actions and facilitate delivery of precise amounts of muscle torque, we primarily use our eyes to provide feedback in a closed-loop control scheme. This ability to control an inherently unstable object by vision-only feedback demonstrates an exceptionally high degree of voluntary motor skill. Despite the pervasiveness of vision-based stabilisation in humans and animals, relatively little is known about the neural strategies used to achieve this task.
In the last few decades, with advancements in technology, we have tried to impart the skill of vision-based object stabilisation to machines, with varying degrees of success. Within the context of this research, we continue this pursuit by employing the classic Cart Inverted Pendulum; an inherently unstable, non-linear system to investigate dynamic object balancing by vision-only feedback. The Inverted Pendulum is considered to be one of the most fundamental benchmark systems in control theory; as a platform, it provides us with a strong, well established test bed for this research.
We seek to discover what strategies are used to stabilise the Cart Inverted Pendulum, and to determine if these strategies can be deployed in Real-Time, using cost-effective solutions. The thesis confronts, and overcomes the problems imposed by low-bandwidth USB cameras; such as poor colour-balance, image noise and low frame rates etc., to successfully achieve vision-based stabilisation.
The thesis presents a comprehensive vision-based control system that is capable of balancing an inverted pendulum with a resting oscillation of approximately ±1º. We employ a novel, segment-based location and tracking algorithm, which was found to have excellent noise immunity and enhanced robustness. We successfully demonstrate the resilience of the tracking and pose estimation algorithm against visual disturbances in Real-Time, and with minimal recovery delay. The algorithm was evaluated against peer reviewed research; in terms of processing time, amplitude of oscillation, measurement accuracy and resting oscillation. For each key performance indicator, our system was found to be superior in many cases to that found in the literature.
The thesis also delivers a complete test software environment, where vision-based algorithms can be evaluated. This environment includes a flexible tracking model generator to allow customisation of visual markers used by the system. We conclude by successfully performing off-line optimization of our method by means of Artificial Neural Networks, to achieve a significant improvement in angle measurement accuracy.Goodrich Engine Control Systems and Balfour Beatty Rail Technologies
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Pang, Wei. "QML-Morven a framework for learning qualitative models /." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25499.
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Fabi, Amanda Jean. "Use of Triptorelin Acetate for Inducing Ovulation and Facilitating Fixed Time Artificial Insemination of Sows Weaned on Small-Scale and Niche Market Pig Farms." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/77395.
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Developing a single fixed-time artificial insemination (FTAI) protocol would benefit small-scale and niche market pork producers by decreasing semen costs and labor associated with detection of estrus. The objective of this study was to test the efficacy of an artificial insemination (AI) breeding system using triptorelin acetate, a GnRH agonist (OvuGel®; JBS United Animal Health, LLC, Sheridan, IN) that induces ovulation. A total of 96 sows (parity, 3.5 ± 0.2; body condition score (BCS), 2.5 ± 0.07) were weaned (h 0) after a 24.8 ± 0.6 d lactation on five participating small swine farms and allocated to one of four treatment groups: 1) TRT1: (n = 24) OvuGel applied intravaginally at h 96 and AI at h 120; 2) TRT2: (n = 24) P.G. 600® (400 IU eCG and 200 IU hCG, Merck Animal Health, Inc., De Sota, KS) injected intramuscularly at weaning, OvuGel at h 96 and AI at h 120; 3) TRT3: (n = 24) P.G. 600 at weaning, and AI at 0 and 24 h after first detection of estrus; and 4) TRT4: (n = 24) AI at 0 and 24 h after first detection of estrus. Treatments 1 and 2 were FTAI protocols with sows being inseminated without regard to estrus onset. Treatments 3 and 4 were consistent with current industry AI practices. The proportion of females displaying estrus by d 7 post-weaning was greater (P < 0.05) for sows that received OvuGel (94.5 %) compared to sows that did not receive OvuGel (82.2 %). There were no effects (P > 0.05) of P.G. 600 or P.G. 600 x OvuGel on females displaying estrus by d 7 or d 10 post-weaning. Weaning to estrus interval was decreased (P < 0.05) for sows that received P.G. 600 (4.9 ± 0.4 d) compared to sows that did not receive P.G. 600 (5.4 ± 0.4 d). There were no effects (P > 0.05) of OvuGel or P.G. 600 x OvuGel on the weaning-to-estrus interval. There were no effects of P.G. 600, OvuGel or P.G. 600 x OvuGel (P > 0.1) on pregnancy rate (total sows pregnant/inseminated) (61.2 %), total litter size (11.3), number born dead (1.0) or number of mummies (0.2). There was an effect (P < 0.05) of P.G. 600 x OvuGel on total born live (10.2). Sows treated with OvuGel had a greater number of live piglets born per semen dose (5.4) compared to sows that did not receive OvuGel (3.2) (P < 0.05). These results suggest that FTAI protocols may be employed on small-scale pig farms without compromising reproductive performance.Master of Science
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Mouré, Anne. "Stratégies pour remédier à l'hypoxie dans le pancréas bio-artificiel." Thesis, Nantes, Ecole nationale vétérinaire, 2019. http://www.theses.fr/2019ONIR125F.
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Le diabète de type 1 est une maladie chronique causée par la destruction auto-immune des cellules bêta productrices d'insuline dans les îlots pancréatiques. L'allotransplantation d'îlots pancréatiques est déjà une réalité clinique pour le traitement de cette maladie. Cependant, cette stratégie est limitée par la faible disponibilité de pancréas humains et la nécessité d'une immunosuppression à vie. Le pancréas bioartificiel (BAP), basé sur l'encapsulation d'îlots allo- ou xénogéniques dans un matériau immunoprotecteur, est une alternative prometteuse permettant de lever ces barrières. Cependant, l'apport d’02 après transplantation et avant la vascularisation autour du greffon reste un défi majeur pour maintenir l'efficacité thérapeutique du BAP. En effet, l'hypoxie induit une perte de fonction et à terme la mort des cellules des îlots. Dans ce contexte, nos travaux ont pour but de développer et d'évaluer des stratégies pour remédier à l'hypoxie dans le BAP. Dans un premier temps, les îlots de porcs nouveau-nés ont été évalués dans le BAP en tant que source d'îlots résistants à l'hypoxie. Par la suite, une stratégie d'oxygénation efficace pour le BAP a été développée en combinant le transporteur d'02, Hemoxcell (hémoglobine marine, Hemarina) et un générateur chimique d'02 composé de peroxyde de calcium encapsulé en silicone. Enfin, un BAP à géométrie plane régulé en 02 a été conçu et optimisé afin de permettre le maintien d'îlots encapsulés à forte densité en situation d'hypoxie. L'ensemble des résultats obtenus devrait permettre d'améliorer l'efficacité thérapeutique du BAP et d'extrapoler de dispositifs plus réalistes pour la clinique humaine en maintenant l'équilibre en 02Type 1 diabetes is a chronic disease caused by the autoimmune destruction of beta cells within the pancreatic islets. The transplantation of pancreatic alloislets has already entered the clinics for this disorder. However, the shortage of human donor organs and the need for lifelong immunosuppressive treatments to prevent graft rejection strongly limit the extension of this approach to a larger patient population. The development of a bioartificial pancreas (BAP), based on the encapsulation of allo-or xenogeneic islets in an immunoprotective membrane, is gathering interest to overcome the main hurdles of islet allotransplantation. However, maintaining the 02 supply after transplantation and before graft vascularisation remains the major challenge to ensure the BAP therapeutic efficacy over extended periods of lime. lndeed, hypoxia induces islet cell dysfunction and finally cell death. In this context, this work aims to develop and evaluate strategies to overcome the hypoxia-induced damages in the BAP. First, neonate pig islets were evaluated in the BAP as a promising islet source exhibiting resistance to hypoxic damages. Then, an efficient oxygenation strategy for the BAP was developed by combining the 02 carrier HEMOXCell (marine haemoglobin, Hemarina) with an 02 generator composed of silicone-encapsulated calcium peroxide. Finally, a planar device based on this oxygenation strategy was designed and optimised to maintain the 02 balance in the BAP supporting a high islet density in a hypoxic environment. This work should allow to improve the BAP therapeutic efficacy and to scale a more realistic device for human clinical applications by maintaining the 02 balance
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Rizvi, Sophia. "An investigation to reduce mortality of the neonatal pig through development of an ideal artificial milk substitute and the use of avian (vitelline) antibodies." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274671.
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Oliveira, Renan Reis de. "Efeito in vitro da incorporação de colesterol à membrana plasmática de espermatozoides criopreservados de jumentos (Equus asinus) da raça pêga." Universidade Federal de Viçosa, 2010. http://locus.ufv.br/handle/123456789/5660.
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The cryopreservation of donkey semen has shown limitations on fertility that discourages their use as routine for professionals working with this species. Incorporation of cholesterol-loaded cyclodextrin (CLC) has proved a promising alternative to improve the resistance of spermatozoa cryopreservation in several species. The aim of this study was to determine the effects of adding different CLC concentrations on in vitro viability of frozen-thawed Pêga donkey spermatozoa. Twenty-five ejaculates from five donkeys (five ejaculates per animal) were submitted to different concentrations of CLC: 0 mg (control), 1 mg (T1), 2 mg (T2) and 3 mg (T3) / 120 x 106 total spermatozoa for 15 minutes before freezing. Samples were thawed and evaluated for physical integrity of sperm plasma membrane (eosin-nigrosin), functional integrity (HOST), sperm morphology, longevity (TTR), and viability of sperm plasma membrane and acrosome (tested with fluorescent probes - IP/FITC-PNA). Physical parameters were measured by subjective and objective (CASA) evaluation. Treated groups had higher physical and functional integrity plasma membrane (P<0.05) than control. Inclusion of CLC resulted either in higher total and progressive motile (CASA) (P<0,05). There were no differences in the amount of cells with plasmas membrane and acrossome intact by epifluorescence test (P>0.05). No difference was observed for total motility and vigor between treatments during TTR (P>0,05). The use of cholesterol- loaded cyclodextrin increases the resistance of frozen-thawed process, number of cells with motility and viable membranes (P<0,05). Futher studies should be conducted to evaluate the influence of CLC cryopreserved donkey spermatozoa fertility.
A criopreservação de sêmen asinino vem apresentando limitações na fertilidade que desestimulam sua utilização como rotina para profissionais que trabalham com a espécie. A incorporação de colesterol associado à ciclodextrina (CLC) tem se mostrado uma alternativa promissora por melhorar a resistência espermática ao processo de criopreservação em diversas espécies. Objetivou-se verificar os efeitos in vitro da adição de diferentes concentrações de CLC na viabilidade de espermatozóides criopreservados de jumentos da raça Pêga. Vinte e cinco ejaculados de cinco jumentos (cinco ejaculados por jumento) foram incubados a temperatura de laboratório por 15 minutos com diferentes concentrações de CLC: 0 mg (controle - CT), 1 mg (T1), 2 mg (T2) e 3 mg (T3) / 120 x 106 espermatozóides totais, antes do congelamento. As amostras foram descongeladas e avaliadas quanto à integridade física da membrana plasmática (SV), integridade funcional (HOST), morfologia espermática, longevidade (TTR) e viabilidade da membrana plasmática e do acrossoma (teste com sondas fluorescentes - IP/FITC-PNA). Os parâmetros físicos foram avaliador de forma subjetiva e objetiva (CASA). As amostras tratadas com CLC apresentaram maior integridade funcional e física (P<0,05) da membrana plasmática que as amostras do tratamento CT. A inclusão de CLC resultou em um aumento (P<0,05) nos valores de motilidade total e progressiva (CASA) para os três tratamentos quando comparado ao CT. Não foram observadas diferenças (P>0,05) na quantidade de células com a membrana plasmática e acrossoma intactos pelo testes de epifluorescência. Também não foi observada diferença entre os tratamentos durante o TTR para os parâmetros motilidade total e vigor espermático (P>0,05). A xv utilização de colesterol incorporado a ciclodextrina aumenta a resistência espermática aos processos de criopreservação, aumentando o número de células com motilidade e membrana íntegra. Novos estudos devem ser realizados para avaliar o efeito do CLC na fertilidade do sêmen asinino.
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Galv?o, Hannah L?cia Cruz. "Desenvolvimento e aplica??o de uma estrat?gia de controle para o m?todo de eleva??o artificial por bombeio mec?nico." PROGRAMA DE P?S-GRADUA??O EM CI?NCIA E ENGENHARIA DE PETR?LEO, 2016. https://repositorio.ufrn.br/jspui/handle/123456789/22131.
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Na ind?stria petrol?fera, uma ?rea que vem se desenvolvendo e ganhando destaque ? a de automa??o e controle de po?os. Esta por sua vez, vem sendo aplicada aos m?todos de eleva??o artificial, especialmente ao Bombeio Mec?nico (BM), que ? considerado um dos m?todos mais utilizado em ambientes onshore, predominando frente aos outros em n?mero de po?os instalados no Brasil. Diante dessa constata??o, nota-se que evolu??es ao BM podem trazer melhorias ? extra??o de petr?leo no pa?s. Uma evolu??o relevante seria o desenvolvimento e aplica??o de novas estrat?gias e t?cnicas de controle a esse sistema. Nesse sentido, o foco principal deste trabalho foi desenvolver um controlador aplicado ao BM, visando evitar o surgimento de efeitos indesej?veis durante o processo de produ??o e maximizar a efici?ncia de opera??o. A ferramenta desenvolvida consiste em controlar o preenchimento parcial da bomba de fundo, atrav?s da manipula??o da velocidade de bombeio. Para tanto, um controlador Proporcional Integral Derivativo (PID) foi utilizado devido ? sua estrutura vers?til, adaptando-se ?s exig?ncias e limita??es do trabalho. Inicialmente, realizou-se o levantamento bibliogr?fico sobre o m?todo em foco, abrangendo principalmente o papel da carta dinamom?trica de superf?cie e de fundo, os conceitos b?sicos sobre o controle do tipo PID e as principais estrat?gias de controle aplicadas ao BM. No decorrer do trabalho foi desenvolvida uma modelagem matem?tica e computacional para determinar o valor do preenchimento da bomba de fundo. Para a implementa??o do controle, foi utilizada a linguagem de programa??o Visual Basic for Applications (VBA) associada ao seu ambiente de desenvolvimento integrado (IDE), presentes no Microsoft Excel. Para valida??o, utilizou-se o simulador de BM como um po?o virtual e simula??es foram realizadas com o controlador desenvolvido. Para efeito de resultado, observou-se que a estrat?gia desenvolvida foi uma importante ferramenta quando se tratava em potencializar a produ??o por BM, visto que a estrat?gia aplicada proporcionou o controle do preenchimento parcial da bomba de fundo, sem a necessidade de parada de produ??o, ou seja, da unidade de bombeio, o que refletiu numa otimiza??o operacional.
In the oil industry, one area that has been developed and gained highlight is automation and well control, which has been used in artificial lift methods, especially in Sucker-Rod Pump (SRP) that is considered one of the methods more used in onshore regions and it is more applied in Brazil compared to other artificial methods. Therefore, it is noted that enhancements in sucker-rod pump may cause largely improvements in oil extraction in the country. One relevant enhancement would be the development and application of new strategies and control techniques to this system. Then, the main focus of this work was developing a controller applied to sucker-rod rump in order to avoid the appearance of undesirable effects during the production process as well as to maximize the operating efficiency. The developed tool controls the partial filling of the downhole pumps through the manipulation of the pumping velocity. Thus, a Proportional Integral Derivative controller (PID) was used due to its versatile structure, adapting to requirements and work limitations. Initially, literature researches about the SRP method were conducted? covering the function of the surface and downhole dynamometric cards, mainly? the basic concepts about the PID control ? and the main control strategies applied to sucker-rod pump. In this work was developed a mathematical and computational modeling to determine the value of the downhole pumps filling. To implement the controlling was used the Visual Basic for Applications (VBA) programming language associated to its integrated development environment (IDE), which is present in Microsoft Excel. To validate, it was used a sucker-rod pump simulator as a virtual well and simulations were realized with the controller that was created. It was observed that the developed strategy was an important tool when it comes to enhance the production through sucker-rod pump because the strategy that was applied provided a partial control of the downhole pumps without stopping the production, that is, the pumping unit, what reflected an operational optimization.
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Emele, Chukwuemeka David. "Informing dialogue strategy through argumentation-derived evidence." Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=179453.
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In many settings, agents engage in problem-solving activities, which require them to share resources, act on each others behalf, coordinate individual acts, etc. If autonomous agents are to e ectively interact (or support interaction among humans) in situations such as deciding whom and how to approach the provision of a resource or the performance of an action, there are a number of important questions to address. Who do I choose to delegate a task to? What do I need to say to convince him/her to do something? Were similar requests granted from similar agents in similar circumstances? What arguments were most persuasive? What are the costs involved in putting certain arguments forward? Research in argumentation strategies has received signi cant attention in recent years, and a number of approaches has been proposed to enable agents to reason about arguments to present in order to persuade another. However, current approaches do not adequately address situations where agents may be operating under social constraints (e.g., policies) that regulate behaviour in a society. In this thesis, we propose a novel combination of techniques that takes into consideration the policies that others may be operating with. First, we present an approach where evidence derived from dialogue is utilised to learn the policies of others. We show that this approach enables agents to build more accurate and stable models of others more rapidly. Secondly, we present an agent decision-making mechanism where models of others are used to guide future argumentation strategy. This approach takes into account the learned policy constraints of others, the cost of revealing in- formation, and anticipated resource availability in deciding whom to approach. We empirically evaluate our approach within a simulated multi-agent frame- work, and demonstrate that through the use of informed strategies agents can improve their performance.
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Ramos, Geraldo André Raposo. "Neuro-fuzzy based screening for EOR projects and experimental investigation of identified techniques in oilfield operations." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=238793.
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Marcolla, Reinaldo Feliponi. "Investigação e aplicação de técnicas de modelagem e controle de processos baseadas em redes neurais com ajuste em linha utilizando algoritmos genéticos." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/102547.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Engenharia QuímicaMade available in DSpace on 2013-07-16T01:15:04Z (GMT). No. of bitstreams: 1 212388.pdf: 3238022 bytes, checksum: 577ca137680a69037adb276e4b6eaa1f (MD5)
Neste trabalho foi realizado um estudo em torno de um sistema de controle de temperatura, o qual apresenta não-linearidades e perturbações difíceis de serem modeladas. Inicialmente foi investigada a aplicação de um controlador linear PID, ajustado segundo metodologias clássicas da pré-sintonia segundo práticas simplificadas de identificação do sistema em questão. Os resultados observados para o controlador PID não foram considerados satisfatórios devido a pouca informação a respeito da dinâmica do processo que fica agregada ao modelo utilizado, bem como o tempo morto envolvido nas ações de controle. O fato do controlador PID não apresentar bom desempenho para sistemas com dinâmica variável, como caso do sistema estudado foi demonstrado.
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Corsar, David. "Developing knowledge-based systems through ontology mapping and ontology guided knowledge acquisition." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25800.
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Menezes, Rosemberg Fernandes de. "?Efeitos da til?pia do Nilo (Oreochromis niloticus) e do enriquecimento por nutrientes sobre a comunidade planct?nica em um lago artificial no semi-?rido brasileiro." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12476.
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Previous issue date: 2008-06-02Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
?The major aim of this study was to test the hypothesis that the introduction of the Nile tilapia (Oreochromis niloticus) and the enrichment with nutrients (N and P) interact synergistically to change the structure of plankton communities, increase phytoplankton biomass and decrease water transparency of a semi-arid tropical reservoir. One field experiment was performed during five weeks in twenty enclosures (8m3) to where four treatments were randomly allocated: with tilapia addition (T), with nutrients addition (NP), with tilapia and nutrients addition (T+NP) and a control treatment with no tilapia or nutrients addition (C). A two-way repeated measures ANOVA was done to test for time (t), tilapia (T) and nutrient (NP) effects and their interaction on water transparency, total phosphorus, total nitrogen, phytoplankton and zooplankton. The results show that there was no effect of nutrient addition on these variables but significant fish effects on the biomass of total zooplankton, nauplii, rotifers, cladocerans and calanoid copepods, on the biovolume of Bacillariophyta, Zygnemaphyceae and large algae (GALD ? 50 ?m) and on Secchi depth. In addition, we found significant interaction effects between tilapia and nutrients on Secchi depth and rotifers. Overall, tilapia decreased the biomass of most zooplankton taxa and large algae (diatoms) and decreased the water transparency while nutrient enrichment increased the biomass of zooplankton (rotifers) but only in the absence of tilapia. In conclusion, the influence of fish on the reservoir plankton community and water transparency was greater than that of nutrient loading. This finding suggests that biomanipulation should be a greater priority in the restoration of eutrophic reservoirs in tropical semi-arid regions
?O principal objetivo deste estudo foi testar a hip?tese de que a introdu??o da til?pia do Nilo (Oreochromis niloticus) e o enriquecimento por nutrientes (N e P) interagem sinergicamente ocasionando mudan?as na estrutura da comunidade planct?nica atrav?s do aumento da biomassa fitoplanct?nica e diminui??o da transpar?ncia da ?gua em um reservat?rio tropical do semi-?rido. Um experimento de campo foi realizado durante cinco semanas em vinte mesocosmos (8m3) nos quais quatro tratamentos foram alocados aleatoriamente: com adi??o de til?pia (T), com adi??o de nutrientes (NP), com adi??o de til?pia e nutrientes (T+NP) e um tratamento controle sem adi??o de til?pia ou nutrientes (C). Uma ANOVA bifatorial com medidas repetidas foi realizada para testar os efeitos do tempo, da til?pia (T) e dos nutrientes (NP) e seus efeitos de intera??o sobre a transpar?ncia da ?gua, f?sforo total, fitopl?ncton e zoopl?ncton. Os resultados mostraram que n?o houve efeito da adi??o de nutrientes sobre essas vari?veis mas houve um efeito significativo dos peixes sobre a biomassa do zoopl?ncton total, n?uplios, rot?feros, clad?ceros e cop?podos calan?ides, sobre o biovolume de Bacillariophyta, Zygnemaphyceae e algas de grande porte (GALD ? 50?m) e sobre a profundidade do disco de Secchi. Al?m disso, foi encontrado um efeito significativo da intera??o entre as til?pias e nutrientes sobre a profundidade do disco de Secchi e tamb?m sobre a biomassa de rot?feros. As til?pias diminu?ram a biomassa da maioria dos taxa zooplanct?nicos, das algas de grande porte e diminu?ram a transpar?ncia da ?gua, enquanto que o enriquecimento por nutrientes aumentou a biomassa do zoopl?ncton (rotiferos) mas somente na aus?ncia das til?pias. Portanto podemos concluir que a influ?ncia dos peixes sobre a comunidade planct?nica do reservat?rio e a transpar?ncia da ?gua foi maior do que o aporte por nutrientes, sugerindo assim que a biomanipula??o deve ter maior prioridade na restaura??o de reservat?rios eutrofizados em regi?es semi-?ridas tropicais
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De, Donno Giulia. "Three dimensional strain analysis of vertebrae with artificial metastases through digital volume correlation." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/19911/.
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Bone is a common site for metastases and spine represent the most frequent site. Lytic lesions are associated with the loss of bone tissue, which can compromise the mechanical competence of the vertebra, leading to spine instability. Rigid stabilization is a solution, but it is a complex surgery, that can be very critical for oncologic patients; on the other hand, an untreated metastasis can lead to mechanical failure of the bone, leading to pain, immobilization and in the worst case, paralysis.
In this study, a protocol to analyse the strain with simulated lytic metastasis under compressive loading has been developed and optimized using a porcine vertebra. The strain distribution has been measured experimentally using micro-computed tomography (micro-CT) and Digital Volume Correlation (DVC), which provided three-dimensional displacements and strains maps inside the specimen. The ideal parameters for the DVC have been found by analysing two repeated scans in constant strain condition and setting a target of 200 microstrain for the errors (one order of magnitude lower than typical strains in bone subjected to physiological loading conditions). An ideal nodal spacing of 50 voxels (approximately 2 mm) has been chosen and a voxel detection algorithm has been applied to all data to remove regions outside the bone. In order to understand how the presence of the defect could alter the strain distribution, the porcine vertebra has also been subjected to non-destructive compressive load before and after the preparation of a mechanically induced lytic metastasis in the vertebral body. An increase of the 40% of the compressive principal strain after the defect has been found in proximity of the lesion.
This protocol will be used in future studies to analyse the effect of size and position of artificially metastatic lesions in the vertebral body of human spines.
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Sá, Denis Fabrício Sousa de. "MODELOS BASEADOS EM REDES NEURAIS ARTIFICIAIS COM APLICAÇÃO EM CONTROLE INDIRETO DE TEMPERATURA." Universidade Federal do Maranhão, 2015. http://tedebc.ufma.br:8080/jspui/handle/tede/295.
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Previous issue date: 2015-04-10Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The representation of dynamic systems or plants via mathematical models occupies an important position in control system design that allow the performance evaluation of the controller during his development stage. These models are also used as an alternative to solve the problem of the hardness or impracticability to install sensors that measure the controlled variables, the dynamic systems representations enable non-invasive measurement of these variables. As consequence the designer has an alternative way to perform adaptive and optimal sensorless control for a given process. In this dissertation is presented a proposal for control systems schemas and algorithms, based on recurrent neural networks (ANN) and Box-Jenkins models, that are dedicated to sensorless or indirect control of dynamic systems. The proposed models and algorithms are associated with the systems identification and recurrent ANN approaches. The algorithms developed for the AAN training are Backpropagation Accelerated and RLS types that are compared with classical methods and strategies to obtain it online parameters of indirect control of system for a thermal plant, where the actuator is Peltier cell. The performance the parametric models of the plant and adaptive PID digital controllers and linear quadratic regulator (DLQR) that are the main elements of the sensorless temperature control system, are evaluated by means of hybrid simulations, where the algorithms implemented in micro controllers and the plant represented by mathematical models. The performance results of the proposed sensorless control algorithms are promissory, not only, in terms of the control system performance, but also due to the reexibility to deploy it in other dynamic systems.
A representação de sistemas dinâmicos ou plantas por meio modelos matemáticos ocupa uma posição relevante no projeto de sistemas de controle, permitindo que o projetista avalie o desempenho dos controladores durante a fase de desenvolvimento do projeto. Estes modelos também são utilizados para resolver o problema da dificuldade ou impossibilidade da inserção de sensores em plantas para medição de variáveis controladas, onde os modelos viabilizam a mediação não invasiva destas variáveis, fornecendo uma alternativa para realização do controle indireto adaptativo e ótimo de um dado processo. Nesta dissertação apresenta-se o desenvolvimento de modelos propostos baseados em redes neurais artificiais recorrentes para o controle sensorless ou indireto da planta. Os modelos propostos estão associados com as abordagens de Identificação de Sistemas e de RNA's recorrentes. OS algoritmos desenvolvidos para o treinamento das RNAs são do tipo Backpropagation acelerado e RLS, que são comparados com estratégias e métodos clássicos, para obtenção online dos parâmetros do sistema de controle indireto de uma planta térmica, tendo como atuador uma célula Peltier. Para uns de avaliação de desempenho do sistema de controle indireto da planta, os modelos paramétricos e controladores digitais adaptativos do tipo PID e regulador linear quadrático (DLQR) são avaliados por meio de simulações híbridas, sendo os algoritmos dos controladores implementados em microcontroladores e a planta representada por modelos matemáticos. Os resultados apresentados são promissores, não são sentido do desempenho do sistema de controle, mas também nos custos reduzidos para seu desenvolvimento, operação e flexibilidade de aplicação em outros sistemas dinâmicos.
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Biggs, Morgan Eleanore. "Dietary supplementation of saccharin-based artificial sweeteners and capsicum oleoresin as a strategy to mitigate the negative consequences of heat stress on pig growth performance and intestinal physiology." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78279.
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Pigs exposed to elevated ambient temperatures exhibit reduced average daily gain, alterations in muscle and fat deposition during growth phases, and decreased overall health. Negative aspects of gastrointestinal (GI) function, integrity and permeability also result from hyperthermia. Saccharin-based artificial sweeteners have the potential to ameliorate the negative effects of heat stress (HS) by increasing GI GLP-2 production while capsicum oleoresin has been shown to reduce inflammatory response. Study objectives were to examine the effects of two artificial sweeteners, neohesperidin dihydrochalcone and saccharin, in combination with capsicum oleoresin (TakTik Sweet Heat , Pancosma, SA) on growth performance of pigs. Forty-eight pigs (12 weeks of age, 47.3 ± 7.6kg) were assigned to six treatments: thermal neutral conditions (21°C) fed ad libitum with (TN+) or without supplement (TN-), heat stress (35°C) fed ad libitum with (HS+) or without supplement (HS-), and thermal neutral conditions pair-fed to HS intake with (PFTN+) or without supplement (PFTN-). Dietary supplementation began 2 days prior to the 3-day environmental treatment period. Body weight was recorded on day -1 and day 3 relative to start of environmental treatment. Body temperature (BT) and respiration rate (RR) were measured thrice daily and feed intake (FI) were recorded daily. Blood samples were collected on day -1 and day 3 to determine metabolite profiles and immune response. Following sacrifice, sections of duodenum, ileum, and colon were collected for histology. Pigs in HS conditions had increased average BT and RR (~2.7-fold) compared to TN and PFTN groups (P<0.01). Irrespective of day, HS+ animals had increased respiration rates when compared to HS- animals (P<0.04). Heat stress decreased FI compared to TN groups. Regardless of treatment, supplement increased feed efficiency by 0.12kg (P<0.04). Circulating glucose concentration tended to decrease in HS+ and PFTN+ pigs compared to non-supplemented treatments (P=0.1). Circulating insulin increased in HS compared to PFTN (P<0.04), but did not differ from TN. Lymphocyte count tended to be decrease in HS compared to PFTN and TN (P=0.052). Monocyte count increased during HS compared to PFTN (P=0.01), but HS and TN did not differ. Supplement increased basophil count (P<0.03), irrespective of treatment. Ileal villus height tended to decrease during HS and PFTN compared to TN (P<0.08). Duodenal and colon villus height nor duodenal, ileal and colon crypt cell depth did not differ between groups. Overall, TakTik Sweet Heat supplementation increases pig feed efficiency and may improve immune response.Master of Science
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Llajaruna, Pereda Gisella Marilú. "Automatización de la Datación de Equimosis en el Peritaje Médico Legal Peruano mediante Redes Neuronales Artificiales y Procesamiento de Imágenes." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2011. https://hdl.handle.net/20.500.12672/1071.
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Las equimosis poseen un extraordinario interés médico – legal, ya que proporcionan los más valiosos indicios para la reconstrucción de la violencia en los que se produjeron. Tradicionalmente, los médicos de acuerdo a su experiencia utilizan la evaluación visual para determinar la edad de la equimosis, pero esta técnica ha sido sustancialmente subjetiva y ha demostrado ser inexacta y poco fiable.
El propósito de este estudio es desarrollar un sistema inteligente que incorpore el procesamiento de imágenes utilizando la técnica RGB de la metodología de colorimetría con el objetivo de obtener el píxel promedio de la zona indurada de la equimosis y una red Perceptrón Multicapa que tiene como variables de entrada el color promedio de la zona indurada obtenido por el procesamiento de imágenes, el color de piel, edad y sexo del lesionado, la presencia de tejido laxo, tejido óseo y tejido vascular, así como también la temperatura ambiental; las cuales han sido cuidadosamente seleccionadas con la finalidad de obtener una mayor precisión en la datación de equimosis.
El procesamiento de imágenes se implementó en el lenguaje de programación Java, el cual tiene por finalidad obtener el promedio de los pixeles RGB más influyentes de la zona indurada de la equimosis. Así mismo, la fase de aprendizaje y validación de la red Perceptrón Multicapa se realizó con la herramienta matemática MATLAB, utilizando el algoritmo backpropagation que brindó una taza de error de 1.26% y 1.37% respectivamente. En consecuencia, el sistema inteligente propuesto en esta tesis genera una mayor precisión en la datación de equimosis en comparación al 80% de inexactitud de los diagnósticos de los médicos legales.
Palabras clave: datación de equimosis, procesamiento de imágenes, backpropagation.The ecchymosis has a special medical - legal interest, as these provide the most valuable clues for the reconstruction of violence in which they occurred. Traditionally, doctors according to their experience using visual assessment to determine the age of ecchymosis, but this technique has been substantially subjective and has proven to be inaccurate and unreliable. The purpose of this thesis is to develop an intelligent system that incorporates image processing technique using the RGB colorimetric methodology in order to obtain the average pixel of indurated area of ecchymosis and a multilayer perceptron network whose input variables the average color of the indurated area obtained by images processing, color, age and sex of the injured, the presence of loose tissue, bone tissue and vascular tissue, as well as the ambient temperature, which have been carefully selected in order to obtain a more accurate dating of ecchymosis. The image processing is implemented in the Java programming language, which aims to obtain the average of the RGB pixels most influential of indurated area of ecchymosis. Also, the learning and validation phase of the multilayer perceptron network was performed with the mathematical tool MATLAB, using the backpropagation algorithm which provided an error rate of 1.26% and 1.37%, respectively. In consequence, the intelligent system proposed in this thesis generates a more precise dating ecchymosis compared to 80% of incorrect medical diagnoses. Keywords: Dating of ecchymosis, Image processing, Backpropagation.
Tesis
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Li, Cui. "Image quality assessment using algorithmic and machine learning techniques." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted: no access until June 2, 2014, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=26521.
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Thesis (Ph.D.)--Aberdeen University, 2009.With: An image quality metric based in corner, edge and symmetry maps / Li Cui, Alastair R. Allen. With: An image quality metric based on a colour appearance model / Li Cui and Alastair R. Allen. ACIVS / J. Blanc-Talon et al. eds. 2008 LNCS 5259, 696-707. Includes bibliographical references.
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Velasquez, Frias Luisa. "Revisión crítica : eficacia del decúbito prono para el buen manejo de distrés respiratorio en etapa aguda de los pacientes en ventilación mecánica." Bachelor's thesis, Universidad Católica Santo Toribio de Mogrovejo, 2019. https://creativecommons.org/licenses/by-nc-nd/2.5/pe/.
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El distrés respiratorio agudo se presenta como una problemática álgida y frecuente en las unidades de cuidados intensivos, en ese sentido se plantea la presente revisión crítica titulada Eficacia del decúbito prono para el buen manejo de distrés respiratorio en etapa aguda de los pacientes en ventilación mecánica, con el objetivo de determinar y comparar la eficacia del decúbito prono en relación a otras intervenciones en el manejo de distrés respiratorio en etapa aguda en los pacientes en ventilación mecánica, teniendo como pregunta Clínica: ¿Es más eficaz el decúbito prono que otras intervenciones para el buen manejo de distrés respiratorio en etapa aguda en los pacientes en ventilación mecánica? El tipo de investigación es secundaria con enfoque de la enfermería basadas en evidencias en donde las estrategias de búsqueda fueron en base a la revisión de las bibliotecas virtuales BVS, PUBME, GOOGLE ACADEMICO, SCIELO, CUIDEN. Los operadores boleanos que se utilizaron fueron AND, OR. Se obtuvieron 1163 documentos de los cuales se seleccionaron 10 artículos de los mismos que luego de aplicar las guías de validez pasaron 3 artículos para el posterior comentario crítico que es la tercera etapa de la EBE para la cual se utilizó la lista CONSORT, nivel de evidencia 1+,Nivel de recomendación IA, Además con una evidencia que la mortalidad a los 28 días fue significativamente menor en el grupo prono que en el grupo en posición supina: 16,0% (38 de 237 participantes) frente a 32,8% (75 de 229) (P <0,001).Trabajo académico
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Ajit, Suraj. "Capture and maintenance of constraints in engineering design." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted access until May 30, 2112. Online version available for University member only until May, 30 2014, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25928.
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Stefopoulou, Sofia N. "Studies on reproductive traits of the male pig with particular emphasis on artificial insemination of the female : 1. Growth and development aspects of the boar and factors affecting male fertility 2. Semen evaluation." Thesis, University of Aberdeen, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327421.
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Paclisan, Dana-Maria. "Optimisation par la modélisation de l'expérimentation vibratoire des systèmes pile à combustible pour le transport terrestre." Phd thesis, Université de Technologie de Belfort-Montbeliard, 2013. http://tel.archives-ouvertes.fr/tel-00977688.
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Les recherches scientifiques sur la pile à combustible échangeuse de protons (PEMFC) ont, jusqu'il y a peu, concerné presque exclusivement les aspects fondamentaux liés à l'électrochimie, particulièrement la conception, le dimensionnement, les performances et le diagnostic. Récemment, les objectifs de durée de vie ont ouvert un nouvel axe de recherche sur le comportement mécanique de la PEMFC devant conduire à son optimisation statique et dynamique. Parallèlement les installations vibroclimatiques de la plateforme d'essais " Systèmes Pile à Combustible " de Belfort ont été développées. La thèse de Vicky ROUSS soutenue en 2008 montre l'intérêt et le potentiel de la modélisation type " boîte noire " pour simuler le comportement mécanique de la PEMFC, et de la technique des signatures mécaniques expérimentales pour mettre en évidence la présence des phénomènes physiques à l'intérieur de la PEMFC. Dans ce contexte les travaux de la présente thèse ont concerné le pilotage des essais de durabilité par simulation boîte noire temps réel et l'exploitation de cette dernière en vue de la découverte des phénomènes physiques à l'intérieur de la PEMFC. La modélisation par réseaux de neurones des systèmes simples de type oscillateur harmonique a représenté le premier pas pour la définition d'un modèle neuronal de pilotage des essais de durabilité en temps réel. Le cas du système mécanique excité par la base qui correspond à une pile à combustible fixée sur la plateforme vibratoire, a été considéré. L'architecture neuronale optimale a été définie en plusieurs étapes en utilisant différents algorithmes. Elle utilise en entrée le signal de commande du système et la réponse mesurée sur la pile à combustible au moment t et en sortie on obtient la réponse prédite du comportement de la pile à combustible au moment t+1. Cette architecture a été mise au point et validée par des essais sur la plateforme. D'autres essais ont permis de mettre en évidence différents comportements de la pile à combustible en fonction de l'amplitude de sollicitation, de la pression et de la température de la pile à combustible. Les signatures mécaniques obtenues réalisées à partir des essais de durabilité complètent la bibliothèque de signatures déjà existante et mettent en évidence de nouveaux comportements de la pile à combustible.
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Vale, Marcelo Roberto Bastos Guerra. "An?lise comparativa do desempenho de um Controlador Fuzzy acoplado a um PID Neural sintonizado por um Algoritmo Gen?tico com Controladores Inteligentes Convencionais." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15184.
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Previous issue date: 2007-12-05On this paper, it is made a comparative analysis among a controller fuzzy coupled to a PID neural adjusted by an AGwith several traditional control techniques, all of them applied in a system of tanks (I model of 2nd order non lineal). With the objective of making possible the techniques involved in the comparative analysis and to validate the control to be compared, simulations were accomplished of some control techniques (conventional PID adjusted by GA, Neural PID (PIDN) adjusted by GA, Fuzzy PI, two Fuzzy attached to a PID Neural adjusted by GA and Fuzzy MISO (3 inputs) attached to a PIDN adjusted by GA) to have some comparative effects with the considered controller. After doing, all the tests, some control structures were elected from all the tested techniques on the simulating stage (conventional PID adjusted by GA, Fuzzy PI, two Fuzzy attached to a PIDN adjusted by GA and Fuzzy MISO (3 inputs) attached to a PIDN adjusted by GA), to be implemented at the real system of tanks. These two kinds of operation, both the simulated and the real, were very important to achieve a solid basement in order to establish the comparisons and the possible validations show by the results
Neste trabalho ?realizado uma an?lise comparativa entre um controlador fuzzy acoplado aum PID neural ajustado por um AGcom diversas t?cnicas de controle tradicionais, todas elas aplicadas em um sistema de tanques (modelo de 2a ordem n?o linear). Com o objetivo de viabilizar as t?cnicas envolvidas nas an?lises comparativas e validar o controle a ser comparado, foram realizadas simula??es de algumas t?cnicas de controle (PID convencional ajustado por AG, PID Neural (PIDN) ajustado por AG, Fuzzy PI, Fuzzy cascata acoplado a um PIDN ajustado por AG e Fuzzy MISO (3 entradas) acoplado a um PIDN ajustado por AG) para efeitos comparativos com o controlador proposto. Depois de realizar todos os testes simulados, foram eleitas, dentre as t?cnicas testadas na fase de simula??o, algumas estruturas de controle (PID convencional ajustado por AG, Fuzzy PI, Fuzzy cascata acoplado aum PIDN ajustado por AGeFuzzy MISO (3entradas) acoplado a um PIDN ajustado por AG) para serem implementadas no sistema real de tanques. Esses dois modos de opera??o, tanto o simulado como o real, se fizeram importantes para um embasamento s?lido para fazer as compara??es e valida??es poss?veis mostradas nos resultados
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Santos, Sender Rocha dos. "Sistemas inteligentes adaptativos aplicados a um robô auto-equilibrante de duas rodas." Universidade do Estado do Rio de Janeiro, 2015. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=8370.
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The advances and the development of vehicles and autobalance robots make
necessary the investigation of controllers able to meet the various challenges related
to the use of these systems. The focus of this work is to study the equilibrium and
position control of one two-wheeled robot. The particular interest in this application
comes from its structure and its rich physical dynamics. Since this is a complex and
non trivial problem, there is great interest in to analyze intelligent controllers. The first
part of this dissertation discusses the development of a classic PID controller. Then it
is compared with two types of intelligent controllers: On-line Neural Fuzzy Control
(ONFC) and Proportional-Integral-Derivative Neural-Network (PID-NN). Also it is
presented the implementation of controllers in a hadware plataform using the LEGO
Mindstorm kit and in a simulation plataform using the MATLAB-Simulink. Two case
studies are developed. The first one investigates the control of equilibrium and
position of two-wheeled robot on a flat terrain to observe the intrinsec performance in
lack of external factors. The second case studies the equilibrium and position control
of the robot in irregular terrains to investigate the system response under influence of
hard conditions in its environment. Finally, the performance of each controller
developed is discussed and competitive results in the control of two-wheeled robot
are achieved.Com o avanço no desenvolvimento e utilização de veículos e robôs autoequilibrantes, faz-se necessário a investigação de controladores capazes de atender os diversos desafios relacionados à utilização desses sistemas. Neste trabalho foi estudado o controle de equilíbrio e posição de um robô auto-equilibrante de duas rodas. O interesse particular nesta aplicação vem da sua estrutura e da riqueza de sua dinâmica física. Por ser um problema complexo e não trivial há grande interesse em avaliar os controladores inteligentes. A primeira parte da dissertação aborda o desenvolvimento de um controle clássico do tipo PID, para em seguida ser comparado com a implementação de dois tipos de controladores inteligentes: On-line Neuro Fuzzy Control (ONFC) e Proportional-Integral-Derivative Neural-Network (PIDNN). Também é apresentada a implementação dos controladores em uma plataforma de hardware, utilizando o kit LEGO Mindstorm, e numa plataforma de simulação utilizando o MATLAB-Simulink. Em seguida, dois estudos de casos são desenvolvidos visando comparar o desempenho dos controladores. O primeiro caso avalia o controle de equilíbrio e posição do robô auto-equilibrante de duas rodas sobre um terreno plano tendo como interesse observar o desempenho intrínseco do sistema sob ausência de fatores externos. O segundo caso estuda o controle de equilíbrio e posição do robô em terrenos irregulares visando investigar a resposta do sistema sob influência de condições adversas em seu ambiente. Finalmente, o desempenho de cada um dos controladores desenvolvidos é discutido, verificando-se resultados competitivos no controle do robô auto-equilibrante de duas rodas.
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Ruiz, Ríos Albina. "Mejora de las condiciones de vida de las familias porcicultoras del Parque Porcino de Ventanilla, mediante un sistema de biodigestión y manejo integral de residuos sólidos y líquidos, Lima, Perú." Doctoral thesis, Universitat Ramon Llull, 2010. http://hdl.handle.net/10803/9296.
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El present treball constitueix el producte de la recerca d'una solució integral al greu problema social, econòmic i ambiental en què viuen dia a dia centenars de famílies assentades al Parc Porcí de Ventanilla, a Lima-Perú.S'analitza, s'adapta i fa viable l'aplicació de les tecnologies existents a la utilització de les excretes i orins dels porcs i de les aigües residuals dels habitatges com a matèria primera per a la producció de biogàs i altres subproductes, que serveixin com a: font d'energia, de matèries primeres per a la producció orgànica, per a l'ús racional de l'aigua, la planificació del territori i sobretot per la millora dels ingressos de les famílies, tot prioritzant l'ús dels recursos locals i que sigui assumible per les famílies per la seva operació, manteniment i rèplica, la qual cosa va significar treballar en una metodologia participativa involucrant a les famílies en tot el procés.
El presente trabajo constituye el producto de la búsqueda de una solución integral al grave problema social, económico y ambiental en que viven día a día cientos de familias asentadas en el Parque Porcino de Ventanilla, en Lima-Perú.
Se analiza, se adapta y hace viable la aplicación de las tecnologías existentes a la utilización de las excretas y orines de los cerdos y de las aguas residuales de las viviendas como materia prima para la producción de biogás y otros subproductos, que sirvan como: fuente de energía, de insumos para la producción orgánica, para el uso racional del agua, la planificación del territorio y sobre todo para la mejora de los ingresos de las familias, todo ello priorizando el uso de los recursos locales y que sea asumible por las familias para su operación, mantenimiento y réplica, lo cual ha significado trabajar en una metodología participativa involucrando a las familias en todo el proceso.
This work results from the search of an integral solution to the very serious social, economical and environmental problems faced by hundreds of families settled in the Porcine Park of Ventanilla in Lima, Peru.
The existing technologies have been analyzed, adapted and applied to use with pigs' excreta and urine, as well as with households´ wastewater as a feedstock for the production of biogas and other sub products. These will be used as: source of energy; organic production inputs; better management of water, spatial planning; and above all, for the improvement of households' incomes. This process prioritizes the use of local resources and is designed to be self managed by the families in terms of operation, maintenance and replication. These two objectives required working in a participatory approach that involved all the families throughout the complete process.
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Pan, Min, Zhe Hao, Chenggang Yuan, and Andrew Plummer. "Development and control of smart pneumatic mckibben muscles for soft robots." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71262.
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Animals exploit soft structures to move smoothly and effectively in complex natural environments. These capabilities have inspired robotic engineers to incorporate soft actuating technologies into their designs. Developing soft muscle-like actuation technology is one of the grand challenges in the creation of soft-body robots that can move, deform their body, and modulate body stiffness. This paper presents the development of smart pneumatic McKibben muscles woven and reinforced by using conductive
insulated wires to equip the muscles with an inherent sensing capability, in which the deformation of the muscles can be effectively measured by calculating the change of wire inductance. Sensing performance of a variety of weaving angles is investigated. The ideal McKibben muscle models are used for analysing muscle performance and sensing accuracy. The experimental results show that the contraction of the muscles is proportional to the measured change of inductance. This relationship is applied to a PID control system to control the contraction of smart muscles in simulation, and good control performance is achieved. The creation of smart muscles with an inherent sensing capability and a good controllability is promising for operation of future soft robots.
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VIDAL, Juan Ferreira. "Metaheurísticas populacionais: estudo comparativo na sintonia de parâmetros de controladores clássicos." Universidade Federal do Pará, 2016. http://repositorio.ufpa.br/jspui/handle/2011/8299.
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Made available in DSpace on 2017-05-04T12:54:50Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_MetaheuristicasPopulacionaisEstudo.pdf: 1773087 bytes, checksum: f28cd56459c0645ef2523053a2599d4e (MD5) Previous issue date: 2016-12-02
CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico
As metaheurísticas populacionais são técnicas pertencentes ao campo da Inteligência Computacional baseadas em modelos naturais e surgiram como alternativas para resolver problemas de otimização, onde as técnicas tradicionais não podem ser aplicadas, ou ainda onde não se dispõe de um modelo de solução para o problema, fazendo com que a solução seja encontrada por intermédio de meios empíricos. Diante da capacidade de oferecer soluções aceitáveis, em um tempo hábil, para muitos dos problemas complexos encontrados, as metaheurísticas populacionais vêm sendo aplicadas com êxito diferentes problemas de sistemas de controle encontrados na literatura. Este trabalho apresenta, de um modo geral, como as metaheurísticas vêm sendo aplicadas na solução de problemas de controle e realiza um estudo comparativo de desempenho entre quatro algoritmos bioinspirados na sintonia dos parâmetros de um controlador Proporcional-Integral-Derivativo (PID). Foram utilizados os seguintes algoritmos: Algoritmo Genético (AG), Algoritmo genético no Modelo de Ilhas (AGMI), Bacterial Foraging Optimization (BFO) e o Particle Swarm Optimization (PSO). Os resultados demonstram que os algoritmos apresentam um ótimo desempenho para a sintonia do PID, produzindo resposta que atendem as exigências de projetos. Foram utilizados diferentes sistemas com características distintas para avaliar os algoritmos. Considerando os resultados obtidos, o PSO se mostrou como o melhor algoritmo entre os quatros usados, produzindo resposta em um tempo mais rápido e apresentando menor desvio padrão nos ensaios realizados.
Population metaheuristics are techniques belonging to the field of Computational Intelligence and are based on natural models, have emerged as alternatives to solve optimization problems where the traditional techniques cannot be applied, or even where a solution model for the problem is not available with which the solution is found through empirical means. Given these capabilities to provide acceptable solutions in a timely manner for most of the complex problems encountered, metaheuristics has been applied successfully in most of the control system problems found in the literature. This work presents in general how the metaheuristics are being applied in the solution of control problems and performs a comparative study of performance among four algorithms bioinspirados in the tuning of the PID parameters. The following algorithms were used: Genetic Algorithm (AG), Genetic Algorithm in the Islands Model (AGMI), Bacterial Foraging Optimization (BFO) and Particle Swarm Optimization (PSO). The results demonstrate that the algorithms present an excellent performance in the tuning of the PID producing response that met the project requirements. Different systems with different characteristics were used to evaluate the algorithms. The PSO was shown as the best algorithm among the four used, producing response in a faster time and presented lower deviated standard in the trials.
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Minář, Petr. "Nelineární řízení komplexních soustav s využitím evolučních přístupů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-364594.
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Control theory of complex systems by utilization of artificial intelligent algorithms is relatively new science field and it can be used in many areas of technical practise. Best known algorithms to solved similar tasks are genetic algorithm, differential evolution, HC12 Nelder-Mead method, fuzzy logic and grammatical evolution. Complex solution is presented at selected examples from mathematical nonlinear systems to examples of anthems design and stabilization of deterministic chaos. The goal of this thesis is present examples of implementation and utilization of artificial algorithms by multi-objective optimization. To achieve optimal results is used designed software solution by multi-platform application, which used Matlab and Java interfaces. The software solution integrate every algorithms of this thesis to complex solution and it extends possible application of those approaches to real systems and practical world.