Дисертації з теми "Surrogate experiments"

The equations governing the thermodynamic behavior of a military aircraft have been implemented by the Air Force Research Lab (AFRL) and other Integrated Vehicle Energy Technology Demonstration (INVENT) contributors into a cohesive, adaptable, dynamic aircraft simulation program in Mathworks' Simulink®. The resulting model known as the "Tip-to-tail" model meets the design specifications set forth by the INVENT program. The system consists of six intimately linked subsystems that include a propulsion subsystem (PS), air vehicle subsystem (AVS), robust electrical power subsystem (REPS), high power electric actuation subsystem (HPEAS), advanced power and thermal management subsystem (APTMS), and a fuel thermal management subsystem (FTMS). The model's governing equations are augmented with experimental data and supported by defined physical parameters. In order to address the problems associated with the additional power and thermal loads for in more electric aircraft (MEA), this research utilizes exergy analysis and mission-integrated synthesis/design optimization to investigate the potential for improvement in tip-to-tail design/performance. Additionally, this thesis describes the development and integration of higher fidelity transient heat exchanger models for use in the tip-to-tail. Finally, the change in performance due to the integration of new heat exchanger models developed here is presented. Additionally, this thesis discusses the results obtained by performing mission-integrated synthesis/design optimization on the tip-to-tail using heat exchanger design parameters as decision variables. These results show that the performance of the tip-to-thermal management subsystems improves significantly due to the integration of the heat exchanger models. These results also show improvements in vehicle performance due to the mission-integrated optimization.
Master of Science

Le contrôle non destructif électromagnétique (CNDE) est appliqué dans des domaines variés pour l'exploration de défauts cachés affectant des structures. De façon générale, le principe peut se poser en ces termes : un objet inconnu perturbe un milieu hôte donné et illuminé par un signal électromagnétique connu, et la réponse est mesurée sur un ou plusieurs récepteurs de positions connues. Cette réponse contient des informations sur les paramètres électromagnétiques et géométriques des objets recherchés et toute la difficulté du problème traité ici consiste à extraire ces informations du signal obtenu. Plus connu sous le nom de " problèmes inverses ", ces travaux s'appuient sur une résolution appropriée des équations de Maxwell. Au " problème inverse " est souvent associé le " problème direct " complémentaire, qui consiste à déterminer le champ électromagnétique perturbé connaissant l'ensemble des paramètres géométriques et électromagnétiques de la configuration, défaut inclus. En pratique, cela est effectué via une modélisation mathématique et des méthodes numériques permettant la résolution numérique de tels problèmes. Les simulateurs correspondants sont capables de fournir une grande précision sur les résultats mais à un coût numérique important. Sachant que la résolution d'un problème inverse exige souvent un grand nombre de résolution de problèmes directs successifs, cela rend l'inversion très exigeante en termes de temps de calcul et de ressources informatiques. Pour surmonter ces challenges, les " modèles de substitution " qui imitent le modèle exact peuvent être une solution alternative intéressante. Une manière de construire de tels modèles de substitution est d'effectuer un certain nombre de simulations exactes et puis d'approximer le modèle en se basant sur les données obtenues. Le choix des simulations (" prototypes ") est normalement contrôlé par une stratégie tirée des outils de méthodes de " plans d'expérience numérique ". Dans cette thèse, l'utilisation des techniques de modélisation de substitution et de plans d'expérience numérique dans le cadre d'applications en CNDE est examinée. Trois approches indépendantes sont présentées en détail : une méthode d'inversion basée sur l'optimisation d'une fonction objectif et deux approches plus générales pour construire des modèles de substitution en utilisant des échantillonnages adaptatifs. Les approches proposées dans le cadre de cette thèse sont appliquées sur des exemples en CNDE par courants de Foucault

The primary objectives of this work are two-fold. First, additive manufacturing (AM) and rapid prototype (RP) testing are evaluated for use in production of a wind tunnel (WT) models. Second, an approach was developed to incorporate stability and control (SandC) WT data into aircraft conceptual design multidisciplinary design optimization (MDO). Both objectives are evaluated in terms of data quality, time, and cost. FDM(TM) and PolyJet AM processes were used for model production at low cost and time. Several models from a representative tailless configuration, ICE 101, were printed and evaluated for strength, cost and time of production. Furthermore, a NACA 0012 model with 20% chord flap was manufactured. Both models were tested in the Virginia Tech (VT) Open-Jet WT for force and moment acquisition. A 1/15th scale ICE 101 model was prepared for manufacturing, but limits of FDM(TM) technology were identified for production. An approach using WT data was adapted from traditional surrogate-based optimization (SBO), which uses computational fluid dynamics (CFD) for data generation. Split-plot experimental designs were developed for analysis of the WT SBO strategy using historical data and for WT testing of the NACA 0012. Limitations of the VT Open-Jet WT resulted in a process that was not fully effective for a MDO environment. However, resolution of ICE 101 AM challenges and higher quality data from a closed-section WT should result in a fully effective approach to incorporate AM and RP testing in an aircraft conceptual design MDO.
Master of Science

The use of computer modeling is fast increasing in almost every scientific, engineering and business arena. This dissertation investigates some challenging issues in design, modeling and analysis of computer experiments, which will consist of four major parts. In the first part, a new approach is developed to combine data from approximate and detailed simulations to build a surrogate model based on some stochastic models. In the second part, we propose some Bayesian hierarchical Gaussian process models to integrate data from different types of experiments. The third part concerns the development of latent variable models for computer experiments with multivariate response with application to data center temperature modeling. The last chapter is devoted to the development of nested space-filling designs for multiple experiments with different levels of accuracy.

This thesis presents a method for streamlining the process of obtaining and interpreting quantitative data for the purpose of creating a low-fidelity modeling and simulation environment. By providing a more efficient means for obtaining such information, quantitative analyses become much more practical for decision-making in the very early stages of design, where traditionally, quants are viewed as too expensive and cumbersome for concept evaluation. The method developed to address this need uses a Systematic Process for Adaptive Concept Exploration (SPACE). In the SPACE method, design space exploration occurs in a sequential fashion; as data is acquired, the sampling scheme adapts to the specific problem at hand. Previously gathered data is used to make inferences about the nature of the problem so that future samples can be taken from the more interesting portions of the design space. Furthermore, the SPACE method identifies those analyses that have significant impacts on the relationships being modeled, so that effort can be focused on acquiring only the most pertinent information. The results show that the combination of a tailored data set, and an informed model structure work together to provide a meaningful quantitative representation of the system while relying on only a small amount of resources to generate that information. In comparison to more traditional modeling and simulation approaches, the SPACE method provides a more accurate representation of the system using fewer resources to generate that representation. For this reason, the SPACE method acts as an enabler for decision making in the very early design stages, where the desire is to base design decisions on quantitative information while not wasting valuable resources obtaining unnecessary high fidelity information about all the candidate solutions. Thus, the approach enables concept selection to be based on parametric, quantitative data so that informed, unbiased decisions can be made.

With a rapid development of computing power, computer experiments have gained popularity in various scientific fields, like cosmology, ecology and engineering. However, some computer experiments for complex processes are still computationally demanding. A surrogate model or emulator, is often employed as a fast substitute for the simulator. Meanwhile, a common challenge in computer experiments and related fields is to efficiently explore the input space using a small number of samples, i.e., the experimental design problem. This dissertation focuses on the design problem under Gaussian process surrogates. The first work demonstrates empirically that space-filling designs disappoint when the model hyperparameterization is unknown, and must be estimated from data observed at the chosen design sites. A purely random design is shown to be superior to higher-powered alternatives in many cases. Thereafter, a new family of distance-based designs are proposed and their superior performance is illustrated in both static (one-shot design) and sequential settings. The second contribution is motivated by an agent-based model(ABM) of delta smelt conservation. The ABM is developed to assist in a study of delta smelt life cycles and to understand sensitivities to myriad natural variables and human interventions. However, the input space is high-dimensional, running the simulator is time-consuming, and its outputs change nonlinearly in both mean and variance. A batch sequential design scheme is proposed, generalizing one-at-a-time variance-based active learning, as a means of keeping multi-core cluster nodes fully engaged with expensive runs. The acquisition strategy is carefully engineered to favor selection of replicates which boost statistical and computational efficiencies. Design performance is illustrated on a range of toy examples before embarking on a smelt simulation campaign and downstream high-fidelity input sensitivity analysis.
Doctor of Philosophy
With a rapid development of computing power, computer experiments have gained popularity in various scientific fields, like cosmology, ecology and engineering. However, some computer experiments for complex processes are still computationally demanding. Thus, a statistical model built upon input-output observations, i.e., a so-called surrogate model or emulator, is needed as a fast substitute for the simulator. Design of experiments, i.e., how to select samples from the input space under budget constraints, is also worth studying. This dissertation focuses on the design problem under Gaussian process (GP) surrogates. The first work demonstrates empirically that commonly-used space-filling designs disappoint when the model hyperparameterization is unknown, and must be estimated from data observed at the chosen design sites. Thereafter, a new family of distance-based designs are proposed and their superior performance is illustrated in both static (design points are allocated at one shot) and sequential settings (data are sampled sequentially). The second contribution is motivated by a stochastic computer simulator of delta smelt conservation. This simulator is developed to assist in a study of delta smelt life cycles and to understand sensitivities to myriad natural variables and human interventions. However, the input space is high-dimensional, running the simulator is time-consuming, and its outputs change nonlinearly in both mean and variance. An innovative batch sequential design method is proposed, generalizing one-at-a-time sequential design to one-batch-at-a-time scheme with the goal of parallel computing. The criterion for subsequent data acquisition is carefully engineered to favor selection of replicates which boost statistical and computational efficiencies. The design performance is illustrated on a range of toy examples before embarking on a smelt simulation campaign and downstream input sensitivity analysis.

The present study attempted to establish a flashing or solid red light as a surrogate conditioned motivating operation (CMO-S) by pairing the light with the unconditioned motivating operation (UMO) of heat. The effects of the red light were assessed by an ABAB reversal design for three participants and an ABA reversal design for one participant. Baseline sessions consisted of presenting the red light in the absence of the UMO of heat to assess for any behavioral effects of the red light before and after pairing with the UMO of heat. Galvanic Skin Response (GSR) was recorded for all participants as an indirect measure of sweating. Additional dependent variables and the ambient temperature for each participant’s UMO of heat were identified through a temperature and response assessment. The additional dependent variable was drinking water for Participants 2–4 and throat clearing for Participant 1. Results suggest that the flashing red light may have been conditioned as a CMO-S for Participants 2 and 3. Participant 4 did not consume any water during any baseline session, suggesting that the solid red light did not function as a CMO-S after pairing. Results for Participant 1 suggests that throat clearing was controlled by additional unknown variables and was not evoked by the UMO of heat. Results potentially supporting the CMO-S should be interpreted cautiously given study limitations involving temperature control and the extent that the UMO of heat was clearly demonstrated for each participant.

Diesel fuel is composed of a complex mixture of hundreds of hydrocarbons that vary globally depending on crude oil sources, refining processes, legislative requirements and other factors. In order to simplify the study of this fuel, researchers create surrogate fuels with a much simpler composition, in an attempt to mimic and control the physical and chemical properties of Diesel fuel. The first surrogates were single-component fuels such as n-heptane and n-dodecane. Recent advancements have provided researchers the ability to develop multi-component surrogate fuels and apply them to both analytical and experimental studies. The systematic application of precisely controlled surrogate fuels promises to further enhance our understanding of Diesel combustion, efficiency, emissions and particulates and provide tools for investigating new and alternative engine combustion systems. This thesis employed analytical and experimental methods to develop, validate and study a library of multi-component surrogate Diesel fuels. The first step was to design a surrogate fuel to precisely match the physical and chemical properties of a full-range petroleum Diesel fuel with 50 cetane number and a typical threshold soot index value of 31. The next step was to create a Surrogate Fuel Library with 18 fuels that independently varied two key fuel properties: cetane number and threshold soot index. Within the fuel library cetane number ranged from 35 to 60 at three threshold soot index levels of 17, 31 and 48 (low, mid-range and high). Extensive ASTM fuel property tests showed that good agreement with important physical and chemical properties of petroleum Diesel fuel such as density, viscosity, heating value and distillation curve. An experimental investigation was conducted to evaluate the combustion, emissions, soot and exhaust particles from the petroleum Diesel fuel and the matching surrogate fuel. A fully-instrumented single-cylinder Diesel engine was operated with combustion strategies including Premixed Charge Compression Ignition (PCCI), Low-Temperature Combustion (LTC) and Conventional Diesel Combustion (CDC). For combustion, the ignition delay, low-temperature (first stage) and high temperature (second stage) heat-release matched very well. Gaseous emissions, soot and exhaust particles maintained good agreement as exhaust gas recirculation and combustion phasing were varied. This thesis demonstrated that fully representative Diesel surrogate fuels could be tailored with the proper blending of the following hydrocarbon components: n-hexadecane, 2,2,4,4,6,8,8-heptamethylnonane, decahydronaphthalene and 1-methylnaphthalene. It was also established that the volumetric blending fractions of these four components could be varied to independently control the fuel cetane number and threshold soot index while retaining the combustion, physical and chemical properties of full-range petroleum Diesel fuel. The Surrogate Fuel Library provided by this thesis supplies Diesel engine researchers and designers the ability to analytically and experimentally vary fuel cetane number and threshold soot index. This new capability to independently vary two key fuel properties provides a means to further enhance the understanding of Diesel combustion and design future combustion systems that improve efficiency and emissions.
El combustible diésel está compuesto por cientos de hidrocarburos cuya presencia y proporción varía dependiendo del origen del crudo, del proceso de refinado, de los requerimientos legislativos, y de muchos otros factores. Para evitar las dificultades que produce esta variabilidad y complejidad en su composición, en los estudios sistemáticos, los investigadores suelen trabajar con combustibles de sustitución, mucho más sencillos, pero que reproducen las propiedades químicas y físicas del gasóleo. Los primeros combustibles de sustitución estuvieron formados por un solo componente, como el n-heptano y el n-dodecano. Recientemente se han desarrollado combustibles de sustitución multi-componentes, que se aplican tanto a estudios experimentales como de modelado. La aplicación sistemática de combustibles de sustitución controlados con precisión es una vía prometedora para mejorar la comprensión de la combustión Diesel, su eficiencia, y sus emisiones y proporciona herramientas para la investigación de sistemas de combustión nuevos y alternativos. En esta tesis se han empleado métodos experimentales y de cálculo para desarrollar, estudiar y validar una librería de combustibles de sustitución multi-componentes. El primer combustible de sustitución se diseñó para reproducir con precisión las propiedades físicas y químicas de un gasóleo con número de cetano 50 y un índice de hollín umbral (TSI) de 31.El siguiente paso fue crear una biblioteca de combustibles de sustitución con 18 combustibles que pueden modificar independientemente dos propiedades clave del combustible: índice de cetano y TSI. En la biblioteca de combustibles el número de cetano osciló entre 35 y 60 con tres niveles de TSI iguales a 17, 31 y 48 (bajo, medio y alto rango). Los ensayos según la normativa ASTM demostraron una buena coincidencia con las propiedades del gasóleo como densidad, viscosidad, poder calorífico y curvas de destilación. Para comprobar la validez de la librería, se realizó un estudio experimental comparativo sobre el proceso de combustión, las emisiones gaseosas, hollín y partículas de un gasóleo y de su combustible de sustitución ajustado. El estudio se realizó con un motor monocilíndrico Diesel completamente instrumentado y operando con estrategias de combustión en premezcla parcial (PPCI) y de baja temperatura (LTC), además de la combustión Diesel convencional (CDC). Los parámetros de la combustión como el retraso al encendido y la liberación de calor tanto de baja como de alta temperatura se aproximaron muy bien. Las emisiones de gases, hollín y partículas también fueron similares al variar el nivel de EGR y la fase de la combustión. La tesis demuestra que se pueden encontrar combustibles de sustitución perfectamente representativos de un gasóleo corriente, en base a mezclas apropiadas de n-hexadecano, 2,2,4,4,6,8,8-heptamethylnonano, decahidronaftaleno y 1-metilnaftaleno. Asimismo, se concluye que variando la proporción de estos cuatro componentes se puede controlar independientemente el número de cetano y el índice de hollín umbral, a la vez que se mantienen las propiedades físico-químicas y de combustión del gasóleo. La librería de combustibles de sustitución definida en esta tesis es una herramienta a disposición de los investigadores para profundizar en el conocimiento de la combustión diésel y avanzar en el diseño de sistemas futuros de combustión con mejor rendimiento y menores emisiones.
El combustible Diesel està compost per centenars d'hidrocarburs, la presència i proporció dels quals varia depenent de l'origen del cru, del procés de refinat, dels requeriments legislatius, i de molts altres factors. Per a evitar les dificultats que produeix aquesta variabilitat i complexitat en la seua composició, en els estudis sistemàtics, els investigadors solen treballar amb combustibles de substitució, molt més senzills, però que reprodueixen les propietats químiques i físiques del gasoil. Els primers combustibles de substitució van estar formats per un sol component, com el n-heptà i el n-dodecà. Recentment s'han desenvolupat combustibles de substitució multi-components, que s'apliquen tant a estudis experimentals com de modelatge. L'aplicació sistemàtica de combustibles de substitució controlats amb precisió és una via prometedora per a millorar la comprensió de la combustió Dièsel, la seua eficiència, i les seues emissions i proporciona eines per a la recerca de sistemes de combustió nous i alternatius. En aquesta tesi s'han emprat mètodes experimentals i de càlcul per a desenvolupar, estudiar i validar una llibreria de combustibles de substitució multi-components. El primer combustible de substitució es va dissenyar per a reproduir amb precisió les propietats físiques i químiques d'un gasoil amb índex de cetà 50 i un índex de sutge límit (TSI) de 31. El següent pas va ser crear una biblioteca de combustibles de substitució amb 18 combustibles que poden modificar independentment dues propietats clau del combustible: índex de cetà i TSI. En la biblioteca de combustibles l'índex de cetá va oscil·lar entre 35 i 60 amb tres nivells de TSI iguals a 17, 31 i 48 (baix, mitjà i alt rang). Els assajos segons la normativa ASTM van demostrar una bona coincidència amb les propietats del gasoil com a densitat, viscositat, poder calorífic i corbes de destil·lació. Per a comprovar la validesa de la llibreria, es va realitzar un estudi experimental comparatiu sobre el procés de combustió, les emissions gasoses, sutge i partícules d'un gasoil i del seu combustible de substitució ajustat. L'estudi es va realitzar amb un motor monocilíndric Dièsel completament instrumentat i operant amb estratègies de combustió en premescla parcial (PPCI) i de baixa temperatura (LTC), a més de la combustió Dièsel convencional (CDC). Els paràmetres de la combustió com el retard a l'encès i l'alliberament de calor tant de baixa com d'alta temperatura es van aproximar molt bé. Les emissions de gasos, sutge i partícules també van ser similars en variar el nivell d'EGR i la fase de la combustió. La tesi demostra que es poden trobar combustibles de substitució perfectament representatius d'un gasoil corrent, sobre la base de mescles apropiades de n-hexadecà, 2,2,4,4,6,8,8-heptamethylnonà, decahidronaftalé i 1-metilnaftaleno. Així mateix, es conclou que variant la proporció d'aquests quatre components es pot controlar independentment l'índex de cetà i l'índex de sutge límit, alhora que es mantenen les propietats físic-químiques i de combustió del gasoil. La llibreria de combustibles de substitució definida en aquesta tesi és una eina a la disposició dels investigadors per a aprofundir en el coneixement de la combustió Diesel i avançar en el disseny de sistemes futurs de combustió amb millor rendiment i menors emissions.
Szymkowicz, P. (2017). ANALYTICAL AND EXPERIMENTAL INVESTIGATION OF MULTI-COMPONENT SURROGATE DIESEL FUELS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90406
TESIS

Large scale, multidisciplinary, engineering designs are always difficult due to the complexity and dimensionality of these problems. Direct coupling between the analysis codes and the optimization routines can be prohibitively time consuming. One way of tackling this problem is by constructing computationally cheap(er) approximations of the expensive simulations, that mimic the behavior of the simulation model as closely as possible. This paper presents a data driven, surrogate based optimization algorithm that uses a trust region based sequential approximate optimization (SAO) framework and a statistical sampling approach based on design of experiment (DOE) arrays. The algorithm is implemented using techniques from the two packages SURFPACK and SHEPPACK that provide a collection of approximation algorithms to build the surrogates and three different DOE techniques: full factorial (FF), Latin hypercube sampling (LHS), and central composite design (CCD) are used to train the surrogates. The biggest concern in using the proposed methodology is the generation of the required database. This thesis proposes a data driven approach where an expensive simulation run is required if and only if a nearby data point does not exist in the cumulatively growing database. Over time the database matures and is enriched as more and more optimizations are performed. Results show that the response surface approximations constructed using design of experiments can be effectively managed by a SAO framework based on a trust region strategy. An interesting result is the significant reduction in the number of simulations for the subsequent runs of the optimization algorithm with a cumulatively growing simulation database.
Master of Science

En 2016, les combustibles fossiles représentaient environ 80% de l'approvisionnement mondial total en énergie primaire. Cependant, cette ressource est limitée et a un impact énorme sur la pollution de l'environnement en raison de la production de gaz à effet de serre. C’est pourquoi le monde industriel et des transports s’intéressent aux biocarburants, en particulier aux bio-huiles, afin de réduire considérablement les émissions de gaz à effet de serre. Le projet IMPROOF est un projet financé par l'Union européenne dans le cadre du programme SPIRE. Son objectif est d'améliorer de 20% l'efficacité énergétique des fours de vapocraquage et, parallèlement, de réduire de 25% par tonne d'éthylène les émissions de polluants tels que les NOx ou les gaz à effet de serre. Cette thèse porte sur l'utilisation de combustibles de substitution, notamment de bio-huiles, pour le chauffage des fours de vapocraquage. Afin de mieux évaluer l'oxydation ou la pyrolyse de la bio-huile, une revue bibliographique des publications traitant de la composition des bio-huiles a été réalisée. Il ressort de cette revue que les bio-huiles peuvent être décrites comme un mélange composé de six principaux types de composés chimiques : les alcools, les aldéhydes, les acides carboxyliques, les furannes et leurs dérivés, les composés aromatiques oxygénés et les composés azotés organiques. Afin de compléter certaines lacunes relevées dans la littérature, le but de cette thèse était de produire un nouvel ensemble de données expérimentales pour certaines molécules appartenant aux cinq premières familles chimiques précédemment présentées. Un réacteur agité par jets a été choisi pour réaliser les expériences en raison de son homogénéité de concentration et de composition. Ce type de réacteur «idéal» convient en effet pour le développement de données fiables pour le développement et la validation de modèles cinétiques. Au cours de ce travail, huit combustibles ont été sélectionnés et étudiés : le n-butanol, le n-pentanol, le n-butanal, le n-pentanal, l’acide butanoïque, l’acide pentanoïque, le furane ainsi que le benzaldéhyde. Pour chacun de ces carburants, les résultats expérimentaux ont été utilisés pour développer et valider un modèle cinétique. Ces modèles ont ensuite été utilisés pour étudier les voies de décomposition des espèces étudiées
In 2016, fossil fuels represented about 80% of the world total primary energy supply. However, this resource is limited and has a huge impact on the environment pollution because of the production of greenhouse gases. In order to drastically reduce greenhouse gases emissions, a focus on biofuels, and especially bio-oils, is made in the industrial world and for transportation. The IMPROOF project is funded by the European Union under the SPIRE framework. Its objective is to improve the energy efficiency in the case of steam cracking furnaces by 20% and in parallel to decrease by 25% per ton of ethylene the emission of pollutants like NOx or greenhouse gases. This PhD is focused on the part concerning the use of alternative fuels and especially bio-oils for the heating of the steam cracking furnaces. To better assess bio-oil oxidation or pyrolysis, a bibliographical review about the publications dealing with the composition of bio-oils have been performed. From this review, it comes out that bio-oils could be described as a mixture composed of six main types of chemical compounds: alcohols, aldehydes, carboxylic acids, furans and derivatives, oxygenated aromatic compounds and nitrogen organic compounds. In order to complete some detected lack in the literature, the aim of this thesis was to produce a new experimental dataset for molecules owning to the five first chemical families previously presented. A jet-stirred reactor was chosen to perform the experiments, due to its homogeneity in concentration and composition. This kind of “ideal” reactor is indeed convenient for the development of reliable data for the development and validation of kinetic models. During this work, eight fuels were selected and studied: n-butanol, n-pentanol, n-butanal, n-pentanal, butanoic acid, pentanoic acid, furan and benzaldehyde. For each fuel, the experimental results were used to develop and validate a kinetic model. Those models were afterward used to study the decomposition pathways of the studied species

Cette thèse traite de l'optimisation sous incertitude de fonctions coûteuses dans le cadre de la conception de systèmes aéronautiques. Nous développons dans un premier temps une stratégie d'optimisation robuste multiobjectifs par modèles de substitution. Au delà de fournir une représentation plus rapide des fonctions initiales, ces modèles facilitent le calcul de la robustesse des solutions par rapport aux incertitudes du problème. L'erreur de modélisation est maîtrisée grâce à une approche originale d'enrichissement de plan d'expériences qui permet d'améliorer conjointement plusieurs modèles au niveau des régions de l'espace possiblement optimales. Elle est appliquée à la minimisation des émissions polluantes d'une chambre de combustion de turbomachine dont les injecteurs peuvent s'obstruer de façon imprévisible. Nous présentons ensuite une méthode heuristique dédiée à l'optimisation robuste multidisciplinaire. Elle repose sur une gestion locale de la robustesse au sein des disciplines exposées à des paramètres incertains, afin d'éviter la mise en place d'une propagation d'incertitudes complète à travers le système. Un critère d'applicabilité est proposé pour vérifier a posteriori le bien-fondé de cette approche à partir de données récoltées lors de l'optimisation. La méthode est mise en oeuvre sur un cas de conception avion où la surface de l'empennage vertical n'est pas connue avec précision.

La sismicité anthropique a augmenté depuis les dernières décennies en raison de l’intense activité humaine pour la production d’énergie. Cependant, malgré le fait que la simple injection de fluides peut induire/ déclencher des tremblements de terre, dans cette thèse, nous montrons que l’interaction stratégique entre les extractions et les injections de fluides peut contrôler de tels événements sismiques et éventuellement les prévenir. Plus précisément, nous construisons un nouveau cadre mathématique de contrôle robuste des tremblements de terre, qui est ensuite exploité dans des simulations numériques de failles de glissement et de réservoirs de gaz, ainsi que dans de nouvelles expériences de laboratoire à l’échelle décimétrique. Tout d’abord, les paramètres clés qui constituent une stratégie conventionnelle d’atténuation des séismes sont identifiés. Des expériences de substitution sur du papier poreux absorbant montrent que sans la connaissance précise des propriétés de la faille, les injections de fluide risquent de nucléer plus rapidement un grand événement sismique. Afin de faire face à de telles incertitudes, des outils mathématiques rigoureux sont développés en utilisant la théorie moderne du contrôle. Ces outils nécessitent un minimum d’informations sur les propriétés de la faille et les caractéristiques de frottement pour assurer la robustesse. Des simulations numériques sur des failles à glissement latéral vérifient que la prévention des séismes est possible, même en présence de processus de diffusion et en l’absence de mesures suffisantes dans le temps et l’espace. En allant plus loin, les techniques de contrôle développées peuvent également être appliquées dans les grands réservoirs de gaz, où la production de gaz souhaitée peut être atteinte en garantissant des niveaux de sismicité acceptables. Enfin, au cours de cette thèse, un nouvel appareil à triplets d’échelle décimétrique a été conçu, construit et calibré en conséquence. Le contrôle de la pression peut être réalisé, dans cet appareil, en temps réel, grâce à un régulateur de pression électro-pneumatique à réponse rapide. Comme preuve de concept, le régulateur développé est branché dans cet appareil et en utilisant des spécimens imprimés en 3D à base de sable (pour promouvoir la répétabilité expérimentale), nous parvenons, pour la première fois, à prévenir les tremblements de terre en laboratoire et à conduire le système de manière asismique vers un point d’équilibre de plus faible énergie
Anthropogenic seismicity has been increased since the last decades due to the intense human activity for energy production. However, despite the fact that merely injection of fluids can induce/trigger earthquakes, in this thesis, we show that the strategic interplay between fluid extractions and injections can control such seismic events and eventually prevent them. More specifically, a novel mathematical framework of robust earthquake control is built which in turn is exploited in numerical simulations of strike-slip faults and gas reservoirs, as well as in new laboratory experiments of decimetric scale. First, the key parameters which constitute a conventional earthquake mitigation strategy are identified. Surrogate experiments on absorbent porous paper show that without the precise knowledge of the fault properties, fluid injections risk to nucleate faster a large seismic event. In order to tackle such uncertainties, rigorous mathematical tools are developed using modern control theory. These tools require minimal information of fault’s properties and frictional characteristics to assure robustness. Numerical simulations on strike-slip faults verify that earthquake prevention is possible, even in the presence of diffusion processes and the absence of sufficient measurements both in time and space. Going a step further, the developed control techniques can also be applied in large gas reservoirs, where the desired gas production can be achieved assuring acceptable seismicity levels. Finally, during this thesis, a novel triplet apparatus of decimetric scale has been designed, constructed and calibrated accordingly. Pressure control can be achieved, in this machine, in real-time, through a fast response electro-pneumatic pressure regulator. As a proof of concept, the developed controller is plugged in this apparatus and by using sand-based 3D-printed specimens (to promote experimental repeatability), we manage, for the first time, to prevent laboratory earthquakes and drive the system aseismically to an equilibrium point of lower energy

Background. Non-porous environmental surfaces accidentally/deliberately contaminated with bioagents might play a role in the spread of infections. The risk of such spread can be reduced with judicious use of liquid chemical disinfectants. Such chemicals are usually applied directly on the target surface as a liquid by immersion, flooding, spray, or by wiping with a disinfectant-wetted fabric. However, the assessments and label claims of microbicidal activities of such chemicals are often based on testing against individual classes of microbes without an appropriate soil load, while pathogens in the field are either unknown or may exist as mixtures in body fluids or other organic/inorganic debris. Further more, the influence of the mechanical action of wiping in decontaminating surfaces is hardly ever assessed. Wiping microbially-contaminated surfaces with an ineffective disinfectant may also spread localized contamination over a wider area, thus enhancing the risk of spread of infections. The potential impact of such spread remains virtually unknown. This study was, therefore, aimed at filling these three gaps in our knowledge. Experimental. To simulate field conditions better, the challenge was a cocktail of bacterial spores (Geobacillus stearothermophilus ), a vegetative bacterium (Acinetobacter baumannii), a mycobacterium (Mycobacterium terrae), and a non-enveloped virus (hepatitis A) in a soil load. Disks (1 cm in diameter) of brushed stainless steel were used as prototypical hard, non-porous environmental surface. Each disk received 10 muL of the microbial suspension. The inoculum was then dried prior to direct contact with the test disinfectant or assessing the effect of wiping for decontamination and transfer of contamination. In both decontamination methods, normal buffered saline (NBS) was used as the control fluid. Results. The microbial mixture successfully evaluated the efficacy claims and spectrum of activity of disinfectants concurrently, with no major differences in inactivation of microbes when challenged alone or as a mixture. Surprisingly, peracetic acid (PAA; 1,000 ppm) and accelerated hydrogen peroxide (AHP)-based formulations (40,000 to 70,000 ppm) reduced the viability of the spores to undetectable levels, but without complete inactivation of the virus at the same contact time and temperature. Chlorine dioxide (CD) and a 5.25% (w/v) solution of sodium hypochlorite, i.e., domestic bleach (DB), showed the broadest spectrum of microbicidal activity. However, their activities depended on air temperature. While CD (500 and 1,000 ppm) and DB (5,000 ppm) completely inactivated HAV and the spores at room temperature (∼22-24°C), these formulations only killed the virus at 4°C but not the spores. M. terrae and A. baumannii were relatively readily inactivated and proved to be very similar in their sensitivities to all the tested chemicals. In general, wiping with a disinfectant-wetted fabric was more effective than direct kill for decontamination. Our data suggested that applying a formulation directly on to a contaminated surface, letting it dry, and then wiping the surface with a disinfectant helped achieve greater log10 reductions while reducing substantially the risk of transfer of contaminants to clean areas. Conclusions. This study assessed the relative strengths and the spectrum of activity of the tested formulations concurrently and under conditions more akin to those expected under field conditions. Incorporation of a cocktail of microorganisms into a single test permitted a more reliable means of classifying microbicides based on their spectrum of activity. Chlorine releasing agents proved to be more effective and have a broader spectrum of activity as compared to the peroxygens. Disinfectant activity depended on air temperature, and none of them was effective against the spores at 4°C. Decontamination by wiping with disinfectants proved to be faster and more effective than direct kill. However, a higher risk of a wider spread of contamination during wiping was also evident in this study. The foundations laid by this investigation should allow more detailed studies using actual infectious bioagents. (Abstract shortened by UMI.)

Turbulent energy dissipation is presented in the theoretical context of the famous Kolmogorov theory, formulated in 1941. Some remarks and comments about this theory help the reader understand the approach to turbulence study, as well as give some basic insights to the problem. A clear distinction is made amongst dissipation, pseudo-dissipation and dissipation surrogates. Dissipation regulates how turbulent kinetic energy in a flow gets transformed into internal energy, which makes this quantity a fundamental characteristic to investigate in order to enhance our understanding of turbulence. The dissertation focuses on experimental investigation of the pseudo-dissipation. Indeed this quantity is difficult to measure as it requires the knowledge of all the possible derivatives of the three dimensional velocity field. Once considering an hot-wire technique to measure dissipation we need to deal with surrogates of dissipation, since not all the terms can be measured. The analysis of surrogates is the main topic of this work. In particular two flows, the turbulent channel and the turbulent jet, are considered. These canonic flows, introduced in a brief fashion, are often used as a benchmark for CFD solvers and experimental equipment due to their simple structure. Observations made in the canonic flows are often transferable to more complicated and interesting cases, with many industrial applications. The main tools of investigation are DNS simulations and experimental measures. DNS data are used as a benchmark for the experimental results since all the components of dissipation are known within the numerical simulation. The results of some DNS were already available at the start of this thesis, so the main work consisted in reading and processing the data. Experiments were carried out by means of hot-wire anemometry, described in detail on a theoretical and practical level. The study of DNS data of a turbulent channel at Re=298 reveals that the traditional surrogate can be improved Consequently two new surrogates are proposed and analysed, based on terms of the velocity gradient that are easy to measure experimentally. We manage to find a formulation that improves the accuracy of surrogates by an order of magnitude. For the jet flow results from a DNS at Re=1600 of a temporal jet, and results from our experimental facility CAT at Re=70000, are compared to validate the experiment. It is found that the ratio between components of the dissipation differs between DNS and experimental data. Possible errors in both sets of data are discussed, and some ways to improve the data are proposed.

Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xi, 120 p.; also includes graphics (some col.). Includes bibliographical references (p. 114-120). Available online via OhioLINK's ETD Center

Cutaneous leishmaniasis (CL) is usually a self-limiting lesion on the skin while visceral leishmaniasis is a progressive, systemic disease with high mortality even if treated. The problem associated with treatment and vector control justifies a search for an effective vaccine which seems to be the only practical means to control the disease. The aim of this study is to identify immunological surrogate marker(s) associated with protection against Leishmania infection. The results indicate that a single dose of ALM+BCG induced Thl-like response but the level of such response is not sufficient for full protection. Accordingly, further evaluation of the vaccine is necessary other strategies multiple injections or changing the adjutant.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
This study sought to: (1) propose a device to the experimental analysis of behavior, (2) present the results of two studies conducted during the testing of equipment, (3) present the first experimental results obtained from monitoring the daily activities of the experimental subject in such equipment and (4) report two experiments in which they attempted to demonstrate empirically the establishment of different surrogate conditioned motivating operations. First, the equipment (Caixa Geradora e Monitora de Cotidiano, CGMC) was presented. During testing of the equipment, two studies were conducted. The first on the effects of light on the daily activities of the experimental subject, the results produced indicated the need for adjustments to equipment, in particular concerning the type and intensity of light used for establishing the cycles of light / dark. The second study occurred during the tests CGMC allowed us to analyze the effects of water restriction (imposed accidentally) of approximately five days on the daily activities of the experimental subject. The results indicate changes in the distribution of the daily activities of the experimental subjects, even those not necessarily related to obtaining water. Once the testing phase of the equipment was finished, a study was conducted in order to monitor the daily activities of the experimental subjects, over the days. The results point to the existence of patterns in the flow behavior that can be modified by various types of variables, such as the cycle of light and dark used, water restrictions and changes in schedules of reinforcement. Finally, two experiments were performed in order to demonstrate empirically the formation of two surrogate conditioned motivating operations. The results point to the failure to establish surrogate conditioned motivating operations
O presente trabalho pretendeu: (1) apresentar uma proposta de equipamento para a análise do comportamento, (2) apresentar os resultados de dois estudos realizados durante os testes do equipamento, (3) apresentar os primeiros resultados experimentais obtidos a partir do monitoramento das atividades diárias do sujeito experimental neste tipo equipamento e (4) relatar dois experimentos nos quais se tentou demonstrar empiricamente o estabelecimento de diferentes operações motivadoras condicionadas substituas. Primeiramente, o equipamento (Caixa Geradora e Monitora de Cotidiano, CGMC) foi apresentado. Durante os testes do equipamento, dois estudos foram realizados. O primeiro sobre os efeitos das luzes sobre as atividades diárias do sujeito experimental; os resultados produzidos indicaram a necessidade de ajustes no equipamento, em especial com relação ao tipo e intensidade da luz utilizada para estabelecer os ciclos de claro/escuro. O segundo estudo ocorrido durante os testes da CGMC permitiu analisar os efeitos de uma restrição hídrica (acidentalmente imposta) de aproximadamente cinco dias de duração sobre as atividades diárias do sujeito experimental. Os resultados apontam para mudanças na distribuição das atividades diárias do sujeito experimental, mesmo daquelas não necessariamente relacionadas com a obtenção de água. Concluída a fase de testes do equipamento, foi realizado um estudo com o objetivo monitorar as atividades diárias do sujeito experimental, ao longo dos dias. Os resultados obtidos apontam para a existência de padrões no fluxo comportamental que podem ser modificados por diversos tipos de variáveis, como o ciclo de claro-escuro utilizado, restrições hídricas e mudanças nos esquemas de reforçamento. Por fim, dois experimentos foram realizados com o objetivo de se demonstrar empiricamente a formação de duas operações motivadoras condicionas substitutas. Os resultados apontam para o não estabelecimento das operações motivadoras condicionadas substitutas

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Fundação de Amparo a Pesquisa do Estado de São Paulo
Establishing operations (EO`s) are environmental events defined by two of their effects: establishing the effect of a consequence as a reinforcement or a punisher and altering the frequency of any response that, in the past, was related to it. The EO`s are divided in unconditioned and conditioned, being the last ones classified in three different types: surrogate CEO, reflexive CEO, transitive CEO. A lot has recently been published about the importance of establishing operations to Applied Behavior Analysis. However, there is little basic research in the field, especially concerning the surrogate CEO. This work had the objective of demonstrating this EO empirically. For this purpose, experiments were conducted using 8 male Wistar rats, a standard equipment (living cages and experimental box) and a mechanism with seven light spots that would supposedly function as the surrogate CEO. The experimental design involved five phases: (1) determining the subjects` free feeding weight; (2) reducing the amount of food the subjects could eat per day until they would remain at about 80% to 85% of their free feeding weight, concomitantly with the procedure to establish the surrogate CEO; (3) shaping the bar press response and implementing the VI 60 s schedule; (4) exposing the subjects to three different deprivation conditions (named minimum, moderate and maximum); (5) testing the surrogate CEO with the six subjects that had completed phase 4. The main results obtained were: a) in relation to the exposure of the subjects to the three different deprivation conditions, the subjects` weights and number of responses emitted per session were affected by them. In general, along the minimum deprivation condition, higher weights and lower number of responses per session were obtained, in comparison with the other conditions; whereas along the maximum deprivation condition, lower weights and higher number of responses were emitted; finally, along the moderate deprivation condition, intermediate results between the two other conditions were obtained; b) in relation to the surrogate CEO tests, data suggest that, at least for four of the six subjects, the mechanism showed (in some of the configurations used in the experimental sessions) effects of a surrogate conditioned establishing operation, which are more visible in lower deprivation conditions (the minimum and moderation conditions)
As operações estabelecedoras (OE´s) são eventos ambientais definidas por dois de seus efeitos: elas estabelecem a eficácia reforçadora/punidora de uma conseqüência e alteram a freqüência de qualquer resposta que, no passado, esteve relacionada a ela. As OE´s são divididas em incondicionadas e condicionadas, sendo que as últimas são classificadas em três tipos diferentes: OEC substituta, OEC reflexiva, OEC transitiva. Muito se tem publicado recentemente sobre a importância das operações estabelecedoras para a análise aplicada do comportamento. Entretanto, existe uma escassez de pesquisas básicas na área, especialmente sobre OEC substituta. Objetivou-se, com este trabalho, realizar uma demonstração empírica deste tipo de OE. Para tanto foram realizados experimentos com 8 ratos machos da raça Wistar, utilizando-se equipamento padrão (caixas-viveiro e caixa experimental) e um mecanismo com sete pontos luminosos que deveria, supostamente, funcionar como a OEC substituta. O delineamento experimental envolveu cinco fases: (1) determinação do peso ad lib dos sujeitos; (2) redução da quantidade diária de alimento até que os sujeitos tivessem atingido de 80% a 85% de seu peso ad lib, concomitantemente com o procedimento para estabelecer a OEC substituta; (3) modelagem da resposta de pressão à barra e implementação de esquema VI 60 s; (4) exposição dos sujeitos a três diferentes condições de privação (chamadas de mínima, moderada e máxima); (5) testes da OEC substituta com os seis sujeitos que terminaram a fase 4. Os principais resultados obtidos foram: a) com relação à exposição dos sujeitos às três diferentes condições de privação, verificou-se os efeitos produzidos por elas sobre o peso dos sujeitos e o número de respostas emitidas por sessão, sendo que, de uma maneira geral, observou-se, na condição de privação mínima, pesos maiores e um menor número de respostas por sessão do que nas outras duas condições, na condição de privação máxima, pesos menores e um maior número de respostas emitidas e, na condição de privação moderada, resultados intermediários entre os das outras duas condições; b) com relação aos testes da OEC substituta, os dados sugerem que, para pelo menos quatro dos seis sujeitos, o mecanismo luminoso apresentou (em algumas das configurações de luzes utilizadas nas sessões experimentais) efeitos de uma operação estabelecedora condicionada substituta, e que estes efeitos são mais visíveis em condições de privação mais amenas (condições mínima e moderada)

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This work consists of three chapters. In the firt chapter, the reader will be introduced to the experimental condition where the following described experiments were performed. This condition consists of the following equipment/tools: (a) a box where multiple operant responses can be recorded continuously and completely over 24 hr per day (b) the ability to monitor and control experiments remotely and (c ) a device capable of recording in Excel spreadsheet data about the temperature and the relative humidity of the air. The chapter concludes with some suggestions for areas of research in this experimental condition could be used. In Chapter 2 describes an experiment in which a set of daily activities of the expeirmental subject was recorded 24 hr per day while it lived in the experimental conditions described in Chapter 1. The activities recorded in this experiment were: (a) number of pressures to water and food bars, (b) the number of times that the subject entered the nest, (c) number of interactions with the wooden disc and (d) number of turns in the activity wheel. The pressure responses to the bars were reinforced according to a continuous schedule of reinforcement. This experiment was approximately 91 days long. The effects from an accidental deprivation of food, the effects of the light-dark cycle, the temerature and air humidity on the activities of the subject where analysed. Furthermore, peroxides greater stability in daily activities were also discussed. Chapter 3 will describe two experiments in order to verify that sound stimuli could acquire the functions of a substitute conditioned motivating operation (OMC-S). The rat lived 24 hr a day in the experimental condition described in Chapter 1. It was believed that conducting the experiments in these conditions it would be possible to evaluate any additional effects of S-CMO, not only on pressure responses to water bar, but also on other registered activities (the same of Chapter 2). However, these additional effects could not be investigated because the sound stimuli did not acquired the functions of an S-CMO in the two experiments
Este trabalho é composto por três capítulos. No primero capítulo, o leitor será apresentado à condição experimental em que os experimentos descritos a seguir foram realizados. Esta condição é composta pelos seguintes equipamentos/ferramentas: (a) uma caixa onde múltiplas respostas operantes podem ser registradas de forma contínua e completa ao longo de 24 hr por dia, (b) a possibilidade de monitorar e controlar os experimentos remotamente e (c) um dispositivo capaz de registrar em planilhas de Excel os dados referentes à temperatura e à umidade relativa do ar do ambiente. O capítulo é encerrado com algumas sugestões de áreas de pesquisa em que esta condição experimental poderia ser utilizada. No Capítulo 2, é descrito um experimento no qual um conjunto de atividades diárias do sujeito expeirmental foi registrada 24 hr por dia enquanto o sujeito vivia nas condições experimentais descritas no Capítulo 1. As atividades registradas neste experimento foram: (a) número de respostas de pressão às barras de água e alimento, (b) número de vezes em que o sujeito entrava no ninho, (c) número de interações com o disco de madeira e (d) número de voltas na roda de atividades. As respostas de pressão às barras eram reforçadas de acordo com um esquema de reforçamento contínuo. Este experimento teve aproximadamente 91 dias de duração. Foram analisados os efeitos de uma privação acidental de alimento, do ciclo de claroescuro, da temeratura e da humidade relativa do ar sobre as atividades do sujeito. Além disso, os perídos de maior estabilidade nas atividades diárias também foram discutidos. No Capítulo 3 serão descritos dois experimentos com o objetivo de verificar se estímulos sonoros poderiam adquirir as funções de uma operação motivadora condicionada substituta (OMC-S). O sujeito vivia 24 hr por dia na condição experimental descrita no Capítulo 1. Acreditava-se que realizando os experimentos nessas condições seria possível avaliar eventuais efeitos adicionais da OMC-S, não apenas sobre as respostas de pressão à barra de água, mas também sobre as demais atividades registradas (as mesmas do Capítulo 2). Entretanto, esses efeitos adicionais não puderam ser investigados, tendo em vista que os estímulos sonoros não adquiriram as funções de uma OMC-S nos dois experimentos realizados

This thesis consists of three chapters, covering topics in both the design and modeling aspects of computer experiments as well as their engineering applications. The first chapter systematically develops a new class of space-filling designs for computer experiments by splitting two-level factorial designs into multiple layers. The new design is easy to generate, and our numerical study shows that it can have better space-filling properties than the optimal Latin hypercube design. The second chapter proposes a novel modeling approach for approximating computationally expensive functions that are not second-order stationary. The new model is a composite of two Gaussian processes, where the first one captures the smooth global trend and the second one models local details. The new predictor also incorporates a flexible variance model, which makes it more capable of approximating surfaces with varying volatility. The third chapter is devoted to a two-stage sequential strategy which integrates analytical models with finite element simulations for a micromachining process.

This thesis studies the influence of internal nozzle flow characteristics over a large spectrum of experimental conditions and diagnostics. Experiments were carried out for two nozzle geometries---cylindrical and conical single hole nozzles---and three different fuels. Two of the fuels are pure components---n-heptane and n-dodecane---while the third fuel consists of a three-component surrogate to better represent the physical and chemical properties of diesel fuel. Measurements include a complete hydraulic characterization consisting of instantaneous injection rate and spray momentum flux measurements; a high-speed visualization of isothermal liquid spray; a high-speed visualization of the evaporative inert spray, imaging liquid and vapor phases simultaneously and finally, a high-speed visualization of the high temperature reactive spray, imaging vapor phase and OH* chemiluminescence for each injection event. All high-temperature diagnostics were performed in a continuous flow test chamber that allows an accurate control on a wide range of thermodynamic conditions (up to 1000 K and 15 MPa). The experimental findings from this work, and the large database obtained (available for download at: http://www.cmt.upv.es/DD01.aspx), could be used to validate CFD models that could help the community understand the fundamental driving mechanisms behind these observations.
En esta tesis se estudia la influencia del flujo interno sobre un amplio espectro de condiciones y diagnósticos experimentales. Se realizaron experimentos para dos geometrías de tobera---toberas cilíndrica y cónica de un único orificio---y tres combustibles. Dos de los combustibles son puros---n-heptano y n-dodecano--- mientras el tercero es un combustible sustituto que consiste en una mezcla de tres componentes que busca representar mejor las propiedades físicas y químicas del diesel. Las medidas incluyen una caracterización hidráulica completa, compuesta por tasa de inyección y cantidad de movimiento instantáneas; una visualización de alta velocidad del chorro líquido isotermo; una visualización de alta velocidad del chorro inerte evaporativo, con captura simultánea de las fases líquida y vapor y, finalmente, una visualización del chorro reactivo a alta temperatura, con captura de la fase vapor y la quimioluminiscencia del radical OH* para cada evento de inyección. Todos los diagnósticos en condiciones de alta temperatura fueron realizados en una maqueta de alta presión y temperatura de flujo constante que permite controlar con precisión un rango amplio de condiciones termodinámicas (hasta 1000 K y 15 MPa). Los resultados experimentales y la gran base de datos obtenida en este trabajo (disponible en: http://www.cmt.upv.es/DD01.aspx), podrían ser utilizados para validar modelos CFD detallados que podrían ayudar a la comunidad científica a entender mejor los mecanismos fundamentales que producen los resultados observados.
Aquesta tesi estudia la influència del flux intern sobre un gran espectre de condicions i diagnòstics experimentals. Es van realitzar experiments per a dos geometries de tovera---toveres ci¿líndrica i cónica amb un únic orifici---i tres combustibles. Dos dels combustibles són purs---n-heptà i n-dodecà--- mentre el tercer combustible consisteix en una mescla de tres components que formen un combustible substitut que busca representar millor les propietats físiques i químiques del dièsel. Les mesures inclouen una caracterització hidràulica completa, composta per taxa d'injecció i quantitat de moviment instantanis; visualització d'alta velocitat del doll líquid isoterme; visualització d'alta velocitat del doll inert evaporatiu, capturant simultàniament les fases líquid i vapor i, finalment, una visualització del doll reactiu a alta temperatura, capturant la fase vapor i la quimioluminiscència del radical OH per a cada esdeveniment d'injecció. Tots els diagnòstics en condicions d'alta temperatura van ser realitzats en una insta¿lació d'alta pressió i temperatura amb flux constant que permet controlar amb precisió un ampli rang de condicions termodinàmiques (fins a 1000 K i 15 MPa). Els resultats experimentals i la gran base de dades obtinguda en aquest treball (disponible a la web en: http://www.cmt.upv.es/dd01.aspx), podrien ser utilitzats per tal de validar models CFD detallats que podrien ajudar a la comunitat científica a entendre millor els mecanismes fonamentals que produeixen aquestes observacions.
Viera Sotillo, JP. (2017). Experimental study of the effect of nozzle geometry on the performance of direct-injection diesel sprays for three different fuels [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/81857
TESIS

El treball descrit en aquesta tesi fa referència al tractaments de glioblastomes (GBM) GL261 preclínics que creixen en ratolins C57BL/6, també al seguiment no invasiu de la resposta a la teràpia, usant tècniques de ressonància magnètica (RM). El model immunocompetent GL261 GBM s’indueix per injecció estereotàctica de cèl·lules GL261 a l’estriat de ratolins WT C57BL/6. Tres agents terapèutics s’han provat en aquest model: el CX-4945®, inhibidor de la proteïna kinasa II (CK2), i dos agents alquilants d’administració oral usats habitualment en pràctica clínica pel tractament de GBM: la temozolamida (TMZ) i la ciclofosfamida (CPA). La CK2 ha estat descrita com a diana potencial pel tractament del càncer, ja que contribueix en el desenvolupament tumoral, proliferació i supressió de l’apoptosi. A més, nivells elevats d’expressió s’han demostrat en varis tipus de càncer. Malgrat això, el CX-4945, el qual està en fase clínica I/II, no va produir l’efecte beneficiós desitjat descrit per altres autors quan es va usar amb el nostre model de GBM GL261. A més, el tractament d’aquest model amb 3 cicles de TMZ, ja ha estat descrit en el nostre grup amb un augment significatiu de la supervivència. Per contra, la teràpia combinada de 3 cicles TMZ amb CX-4945, inesperadament, va revertir l’efecte beneficiós de la TMZ, el que va suggerir una interferència amb el sistema immunitari relacionat amb el desenvolupament i tractament del càncer. Això ens va portar a considerar l’ús d’un esquema de teràpia metronòmic (administració de dosis baixes separades per períodes iguals i sense llargs períodes de repòs entremig) descrit amb resultats prometedors a la literatura. La CPA, la TMZ i el CX-4945 van ser analitzats en un esquema de teràpia metronòmic a dosis diferents. Dins les diferents estratègies analitzades, els millors resultats es van obtenir amb el protocol metronòmic de teràpia combinada, cada 6 dies, de TMZ i CX-4945, mostrant un increment significatiu en la supervivència. Aquests resultats també van apuntar cap a la probable participació del sistema immunitari en resposta a la teràpia, tot i que es necessitaran futurs estudis d’histopatologia per confirmar aquesta hipòtesis. Altres resultats interessants addicionals van ser: en primer lloc, l’aparició d’un clar edema peritumoral durant moments concrets del tractament quimioterapèutic. En segon lloc, que la metodologia no-invasiva per determinar la resposta a la teràpia basat en l’anàlisi semi-supervisat de fonts d’imatge espectroscòpica de ressonància magnètica (MRSI), prèviament desenvolupat en el nostre grup amb ratolins tractats amb TMZ, també va demostrar ser viable per detectar la resposta induïda pel CPA en el nostre model preclínic. Això suggeriria que es pot observar un “patró metabolòmic de resposta” comú sota diferents estratègies terapèutiques. I en tercer lloc, l’aparició de limfomes trobats en les necròpsies de ratolins curats després de dosis cumulatives elevades de TMZ (480-1400 mg/Kg), suggerint que cal investigar estratègies per disminuir la dosi administrada d’agents alquilants per evitar efectes perjudicials en els ratolins tractats.
Work described in this thesis deals with the treatment of GL261 preclinical glioblastoma (GBM) growing in C57BL/6 mice, as well as with the non-invasive assessment of response to therapy using magnetic resonance (MR) techniques. The GL261 GBM is an immunocompetent model induced by stereotactic injection of GL261 cells into the striatum of C57BL/6 WT mice. Three different therapeutic agents have been tested in this model: CX-4945®, a protein kinase II (CK2) inhibitor, and two oral alkylating agents commonly used in the clinic for GBM treatment, temozolomide (TMZ) and cyclophosphamide (CPA). CK2 has been described as a potential suitable target for cancer treatment because it contributes to tumour development, proliferation, and apoptosis suppression in cancer. In addition, elevated CK2 expression levels have been demonstrated in several cancer types. Nevertheless, CX-4945, which already reached phase I/II clinical trials, did not produce the expected beneficial effect described by others when applied to our GL261 GBM model. Moreover, the GL261 GBM treatment with 3 TMZ cycles had been already described by our group with significant survival improvement. Nevertheless, the combined therapy 3 cycle-TMZ+CX-4945, unexpectedly, reverted the beneficial effect of TMZ, which suggested an interference with the immune cycle related with cancer development and treatment. This lead us to consider the use of a metronomic schedule (administration of low and equally spaced doses of drugs without long rest periods in between) described with promising results in the literature. CPA, TMZ and CX-4945 were assessed in a 6-day schedule metronomic schedule at different doses. Among the different strategies evaluated, best results were obtained with the combined metronomic administration, every 6 days, of TMZ and CX-4945 drugs, showing significant improved survival. This also pointed to the probable paticipation of the host mice immune system in therapy response, although further histopathological studies will be needed to fully confirm this hypothesis. Additional interesting findings were: firstly, a clear peritumoral brain edema appearance during certain stages of chemotherapeutic treatment. Secondly, that the non-invasive method for therapy response assessment based in semi-supervised source analysis of Magnetic Resonance Spectroscopy Imaging (MRSI) data, previously developed in our group with TMZ-treated mice, also proved useful for detecting CPA-induced response in our preclinical model. This would suggest that a common “metabolomics responding pattern” can be observed under different therapeutic strategies. And thirdly, the necropsy findings in mice cured from GL261 GBM after high TMZ cumulative dosage (480-1400 mg/Kg), which presented relevant lymphoma incidence, suggesting that strategies to decrease the administered dose should be investigated to avoid harmful effects in mice treated with alkylating agents.

Les sections efficaces neutroniques des noyaux de courte durée de vie sont des données cruciales pour la physique fondamentale et appliquée dans des domaines tels que la physique des réacteurs ou l'astrophysique nucléaire. En général, l'extrême radioactivité de ces noyaux ne nous permet pas de procéder à des mesures induites par neutrons. Cependant, il existe une méthode de substitution (" surrogate " dans la littérature) qui permet de déterminer ces sections efficaces neutroniques par l'intermédiaire de réactions de transfert ou de réactions de diffusion inélastique. Son intérêt principal est de pouvoir utiliser des cibles moins radioactives et ainsi d'accéder à des sections efficaces neutroniques qui ne pourraient pas être mesurées directement. La méthode est basée sur l'hypothèse de formation d'un noyau composé et sur le fait que la désexcitation ne dépend essentiellement que de l'énergie d'excitation et du spin et parité de l'état composé peuplé. Toutefois, les distributions de moments angulaires et parités peuplés dans des réactions de transfert et celles induites par neutrons sont susceptibles d'être différentes. Ce travail fait l'état de l'art sur la méthode substitution et sa validité. En général, la méthode de substitution fonctionne très bien pour extraire des sections efficaces de fission. Par contre, la méthode de substitution dédiée à la capture radiative est mise à mal par la comparaison aux réactions induites par neutrons. Nous avons réalisé une expérience afin de déterminer les probabilités de désexcitation gamma du 176Lu et du 173Yb à partir des réactions de substitution 174Yb(3He,p)176Lu* et 174Yb(3He,alpha)173Yb*, respectivement, et nous les avons comparées avec les probabilités de capture radiative correspondantes aux réactions 175Lu(n,gamma) et 172Yb(n,gamma) qui sont bien connues. Cette expérience a permis de comprendre pourquoi, dans le cas de la désexcitation gamma, la méthode de substitution donne des écarts importants par rapport à la réaction neutronique correspondante. Ce travail dans la région de terres rares a permis d'évaluer dans quelle mesure la méthode de substitution peut s'appliquer pour extraire des probabilités de capture dans la région des actinides. Des expériences précédentes sur la fission ont aussi pu être réinterprétées. Ce travail apporte donc un éclairage nouveau sur la méthode de substitution.

This thesis tackles issues of particular interest regarding analysis and design of passive components at the mm-wave and Terahertz (THz) bands. Innovative analysis techniques and modeling of complex structures, design procedures, and practical implementation of advanced passive devices are presented. The first part of the thesis is dedicated to THz passive components. These days, THz technology suffers from the lack of suitable waveguiding structures since both, metals and dielectric, are lossy at THz frequencies. This implies that neither conventional closed metallic structures used at microwave frequencies, nor dielectric waveguides used in the optical regime, are adequate solutions. Among a variety of new proposals, the Single Wire Waveguide (SWW) stands out due to its low attenuation and dispersion. However, this surface waveguide presents difficult excitation and strong radiation on bends. A Dielectric-Coated Single Wire Waveguide (DCSWW) can be used to alleviate these problems, but advantages of the SWW are lost and new problems arise. Until now, literature has not given proper solution to radiation on bends and, on the other hand, rigorous characterization of these waveguides lacks these days. This thesis provides, for the first time, a complete modal analysis of both waveguides, appropriated for THz frequencies. This analysis is later applied to solve the problem of radiation on bends. Several structures and design procedures to alleviate radiation losses are presented and experimentally validated. The second part of the thesis is dedicated to mm-wave passive components. These days, when implementing passive components to operate at such small, millimetric wavelengths, to ensure proper metallic contact and alignment between parts results challenging. In addition, dielectric absorption becomes significant at mm-wave frequencies. Consequently, conventional hollow metallic waveguides and planar transmission lines present high attenuation so that new topologies are being considered. Gap Waveguides (GWs), based on a periodic structure introducing an Electromagnetic Bandgap effect, result very suitable since they do not require metallic contacts and avoid dielectric losses. However, although GWs have great potential, several issues prevent GW technology from becoming consolidated and universally used. On the one hand, the topological complexity of GWs difficulties the design process since full-wave simulations are time-costly and there is a lack of appropriate analysis methods and suitable synthesis procedures. On the other hand, benefits of using GWs instead of conventional structures are required to be more clearly evidenced with high-performance GW components and proper comparatives with conventional structures. This thesis introduces several efficient analysis methods, models, and synthesis techniques that will allow engineers without significant background in GWs to straightforwardly implement GW devices. In addition, several high-performance narrow-band filters operating at Ka-band and V-band, as well as a rigorous comparative with rectangular waveguide topology, are presented.
Esta tesis aborda problemas actuales en el análisis y diseño de componentes pasivos en las bandas de onda milimétrica y Terahercios (THz). Se presentan nuevas técnicas de análisis y modelado de estructuras complejas, procedimientos de diseño, e implementación práctica de dispositivos pasivos avanzados. La primera parte de la tesis se dedica a componentes pasivos de THz. Actualmente no se disponen de guías de onda adecuadas a THz debido a que ambos, metales y dieléctricos, introducen grandes pérdidas. En consecuencia, no es adecuado escalar las estructuras metálicas cerradas usadas en microondas, ni las guías dieléctricas usadas a frecuencias ópticas. Entre un gran número de recientes propuestas, la Single Wire Waveguide (SWW) destaca por su baja atenuación y casi nula dispersión. No obstante, como guía superficial, la SWW presenta difícil excitación y radiación en curvas. El uso de un recubrimiento dieléctrico, creando la Dielecric-Coated Single Wire Waveguide (DCSWW), alivia estos inconvenientes, pero las ventajas anteriores se pierden y nuevos problemas aparecen. Hasta la fecha, no se han encontrado soluciones adecuadas para la radiación en curvas de la SWW. Además, se echa en falta una caracterización rigurosa de ambas guías. Esta tesis presenta, por primera vez, un análisis modal completo de SWW y DCSWW, adecuado a la banda de THz. Este análisis es aplicado posteriormente para evitar el problema de la radiación en curvas. Se presentan y validan experimentalmente diversas estructuras y procedimientos de diseño. La segunda parte de la tesis abarca componentes pasivos de ondas milimétricas. Actualmente, estos componentes sufren una importante degradación de su respuesta debido a que resulta difícil asegurar contacto metálico y alineamiento adecuados para la operación a longitudes de onda tan pequeñas. Además, la absorción dieléctrica incrementa notablemente a estas frecuencias. En consecuencia, tanto guías metálicas huecas como líneas de transmisión planares convencionales presentan gran atenuación, siendo necesario considerar topologías alternativas. Las Gap Waveguides (GWs), basadas en una estructura periódica que introduce un efecto de Electromagnetic Bandgap, resultan muy adecuadas puesto que no requieren contacto entre partes metálicas y evitan las pérdidas en dieléctricos. No obstante, a pesar del potencial de las GWs, varias barreras impiden la consolidación y uso universal de esta tecnología. Por una parte, la compleja topología de las GWs dificulta el proceso de diseño dado que las simulaciones de onda completa consumen mucho tiempo y no existen actualmente métodos de análisis y diseño apropiados. Por otra parte, es necesario evidenciar el beneficio de usar GWs mediante dispositivos GW de altas prestaciones y comparativas adecuadas con estructuras convencionales. Esta tesis presenta diversos métodos de análisis eficientes, modelos, y técnicas de diseño que permitirán la síntesis de dispositivos GW sin necesidad de un conocimiento profundo de esta tecnología. Asimismo, se presentan varios filtros de banda estrecha operando en las bandas Ka y V con altas prestaciones, así como una comparativa rigurosa con la guía rectangular.
Aquesta tesi aborda problemes actuals en relació a l'anàlisi i disseny de components passius en les bandes d'ona mil·limètrica i Terahercis. Es presenten noves tècniques d'anàlisi i modelatge d'estructures complexes, procediments de disseny, i implementació pràctica de dispositius passius avançats. La primera part de la tesi es focalitza en components passius de THz. Actualment no es disposen de guies d'ona adequades a THz causa que tots dos, metalls i dielèctrics, introdueixen grans pèrdues. En conseqüència, no és adequat escalar les estructures metál·liques tancades usades en microones, ni les guies dielèctriques usades a freqüències òptiques. Entre un gran nombre de propostes recents, la Single Wire Waveguide (SWW) destaca per la seua baixa atenuació i quasi nul·la dispersió. No obstant això, com a guia superficial, la SWW presenta difícil excitació i radiació en corbes. L'ús d'un recobriment dielèctric, creant la Dielecric-Coated Single Wire Waveguide (DCSWW), alleuja aquests inconvenients, però els avantatges anteriors es perden i nous problemes apareixen. Fins a la data, no s'han trobat solucions adequades per a la radiació en corbes de la SWW. A més, es troba a faltar una caracterització rigorosa d'ambdues guies. Aquesta tesi presenta, per primera vegada, un anàlisi modal complet de SWW i DCSWW, adequat a la banda de THz. Aquest anàlisi és aplicat posteriorment per evitar el problema de la radiació en corbes. Es presenten i validen experimentalment diverses estructures i procediments de disseny. La segona part de la tesi es centra en components passius d'ones mil·limètriques. Actualment, aquests components pateixen una important degradació de la seua resposta a causa de que resulta difícil assegurar contacte metàl·lic i alineament adequats per a l'operació a longituds d'ona tan menudes. A més, l'absorció dielèctrica incrementa notablement a aquestes freqüències. En conseqüència, tant guies metàl·liques buides com línies de transmissió planars convencionals presenten gran atenuació, sent necessari considerar topologies alternatives. Les Gap Waveguides (GWs), basades en una estructura periòdica que introdueix un efecte de Electromagnetic Bandgap, resulten molt adequades ja que no requereixen contacte entre parts metàl·liques i eviten les pèrdues en dielèctrics. No obstant, tot i el potencial de les GWs, diverses barreres impedixen la consolidació i ús universal d'aquesta tecnologia. D'una banda, la complexa topologia de les GWs dificulta el procés de disseny atés que les simulacions d'ona completa consumeixen molt de temps i no existeixen actualment mètodes d'anàlisi i disseny apropiats. D'altra banda, és necessari evidenciar el benefici d'utilitzar GWs mitjançant dispositius GW d'altes prestacions i comparatives adequades amb estructures convencionals. Aquesta tesi presenta diversos mètodes d'anàlisi eficients, models, i tècniques de disseny que permetran la síntesi de dispositius GW sense necessitat d'un coneixement profund d'aquesta tecnologia. Així mateix, es presenten diversos filtres de banda estreta operant en les bandes Ka i V amb altes prestacions, així com una comparativa rigorosa amb la guia rectangular.
Berenguer Verdú, AJ. (2017). Analysis and design of efficient passive components for the millimeter-wave and THz bands [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/84004
TESIS

碩士
國立高雄大學
統計學研究所
97
Trajectory-based methodology (TB), proposed by Chiang and Chu (1996), can be used to identified all local extremes of an objectivefunction. In trajectory-based methodology, we iterative to find alocal extreme by a gradient type method, and then to search a decomposition point as the next starting point. However, it might take too much cost in searching decomposition points, especially when the computational cost of function evaluation is very high. Here in order to save the computational cost, a surrogate-assisted method is proposed. The basically idea is to build an inexpensive surrogate surface in a neighborhood of an identified local extreme point, and then the decomposition point search is accomplished on this surrogate surface instead of the true response function. Several numerical experiments are used to demonstrate the performance of this new surrogate-assisted method.

Modern reservoir management typically involves simulations of geological models to predict future recovery estimates, providing the economic assessment of different field development strategies. Integrating reservoir data is a vital step in developing reliable reservoir performance models. Currently, most effective strategies for traditional manual history matching commonly follow a structured approach with a sequence of adjustments from global to regional parameters, followed by local changes in model properties. In contrast, many of the recent automatic history matching methods utilize parameter sensitivities or gradients to directly update the fine-scale reservoir properties, often ignoring geological inconsistency. Therefore, there is need for combining elements of all of these scales in a seamless manner. We present a hierarchical streamline-assisted history matching, with a framework of global-local updates. A probabilistic approach, consisting of design of experiments, response surface methodology and the genetic algorithm, is used to understand the uncertainty in the large-scale static and dynamic parameters. This global update step is followed by a streamline-based model calibration for high resolution reservoir heterogeneity. This local update step assimilates dynamic production data. We apply the genetic global calibration to unconventional shale gas reservoir specifically we include stimulated reservoir volume as a constraint term in the data integration to improve history matching and reduce prediction uncertainty. We introduce a novel approach for efficiently computing well drainage volumes for shale gas wells with multistage fractures and fracture clusters, and we will filter stochastic shale gas reservoir models by comparing the computed drainage volume with the measured SRV within specified confidence limits. Finally, we demonstrate the value of integrating downhole temperature measurements as coarse-scale constraint during streamline-based history matching of dynamic production data. We first derive coarse-scale permeability trends in the reservoir from temperature data. The coarse information are then downscaled into fine scale permeability by sequential Gaussian simulation with block kriging, and updated by local-scale streamline-based history matching. he power and utility of our approaches have been demonstrated using both synthetic and field examples.

The speech of an individual conveys a great deal of information about how their central nervous system (CNS) is performing. Whether they are tired, distressed or suffering from a degenerative disease affecting the brainstem, speech can change as a function of an individual’s condition. Yet, when assessing the speech in an individual on the first occasion, it is often difficult to determine whether their performance is different from a pre-morbid level. Therefore, the repeated acquisition and analysis of a set of brief and simple speech measures could provide information on changes in a patient’s performance over time. This could ultimately lead to the inclusion of objective markers of change in trials of conditions and disorders that currently rely of subjective, clinician derived measures of severity or patient self report, such as pain, depression or fatigue. Furthermore, the information could be used to track patient performance in treatment trials for degenerative disorders, such as Friedreich ataxia or Huntington’s disease.
This thesis aimed to evaluate the practical, experimental and statistical requirements of speech assessment protocols designed to monitor patient performance over time. The research involved a number of studies evaluating methods for acquiring and analysing data, studies examining the stability and sensitivity of speech stimuli, and finally, the functionality of these findings in an experimental model known to induce change in CNS function (i.e., sustained wakefulness).
Methods for acquiring and analysing speech data were designed to provide a balance between the concurrent demands for precision and useability inherent in repeated assessment protocols. Data from these studies provided evidence that techniques offering high levels of useability (e.g., easy to use, automated) are capable of offering adequate precision on broad acoustic measures of timing and frequency. Moreover, these methods could be standardised and automated, allowing non-expert users to collect and analyse data in a controlled and time efficient manner. The second series of experiments systematically documented the stability and responsiveness of speech stimuli within a variety of experimental conditions. These studies were designed to establish the suitability of select speech measures for monitoring change in individuals over time, as stimuli that proved to be both stable (across several re-test intervals) and sensitive to change or impairment were ideal candidates. Finally, a proof of concept study designed to evaluate the efficiency and sensitivity of the proposed methodology was initiated in an experimental model known to induce changes in psychomotor functioning in healthy adults (sustained wakefulness). Significant changes from baseline were observed in speech production as a function of increasing levels of fatigue. These findings are important as they demonstrate the potential of speech as a valid, reliable and sensitive marker of change in conditions where the CNS is subject to stress.

Wastewater epidemiology is an emerging discipline that requires collaborative research involving analytical chemists, drug epidemiologists, and wastewater engineers. Wastewater epidemiology involves the sampling and quantitative analysis of raw wastewaters from communities for illicit drugs and their metabolites. Mass loads (mass per day) and per capita (mg per day per person) are then calculated from concentrations and indicate the approximate quantity of illicit drugs used and excreted by the community. Limitations to wastewater epidemiology include that the population served by wastewater treatment plants within a day and between days is not well known. In addition, biodegradation of illicit drugs during transit in sewers may affect the concentration and mass flows that reach wastewater treatment plants. This thesis describes a series of studies conducted by an international collaboration between scientists and engineers from the United States and Switzerland to answer these two limitations. The experimental approaches for these studies used included high-frequency wastewater sampling strategies, the use of creatinine as a human urinary biomarker, as well as the use of unique locations as test sites including an open community, a prison in the state of Oregon, and a 5 km section of sewer in Zürich Switzerland. In Chapter 2, the diurnal study on the mass flows of illicit drugs or metabolites was formed over four days in a municipality with a population of approximately 55,000 people. The diurnal trends in illicit substances vary by substance. The high (g/day) mass flows of caffeine, methamphetamine, and creatinine indicate that lower-frequency sampling (approximately one sample per h) may representatively capture the use and excretion of these substances. However, lower and episodic mass flows of cocaine and its primary human metabolite, benzoylecgonine, indicate that higher-frequency is needed to accurately assess the use of the cocaine within the municipality. Normalization of illicit substances to creatinine gave between-day trends in illicit and legal substances that differed from non-normalized trends. Resident use of cocaine and methamphetamine were indicated by normalized mass flows that increased during early morning hours while commuters are largely absent from the community. Chapter 3 describes a series of experiments conducted at an Oregon state prison. The prison setting provided a unique opportunity to study a nearly-fixed population of individuals and their corresponding mass flows of illicit substances, the number of doses per person consumed, as well as an opportunity to quantify the level of agreement between numbers of individuals and the measured mass flows of creatinine. Methamphetamine use was more prevalent than cocaine/benzoylecgonine in the prison over the one month study in which single daily (24 h) composite samples of wastewater were collected. The hypothesis that the mass flows of methamphetamine and cocaine would be lower on days on which random urinalysis testing (RUA) is typically conducted by the prison (Monday-Thursday) was rejected. While the mass flows (mg/d) of methamphetamine were less than those for a nearby open community, the number of estimated doses per person was higher for the prison population. A higher number of positive RUA results were obtained for methamphetamine while none were positive for cocaine, which is consistent with the data obtained from wastewater. The hourly (diurnal) trend in methamphetamine mass loads indicated continual methamphetamine use/excretion inside the prison while cocaine and benzoylecgonine were detected in five hourly composite samples. Use of methamphetamine and cocaine by inmates could not be unambiguously distinguished from that of non-inmates (employees and visitors). The observed diurnal trends in creatinine mass loads were similar to those of an open community and are indicative of the general pattern of human wakefulness/activity. Predicted creatinine mass loads based on the total prison (inmates + non-inmates) were in good agreement with the measured mass loads, which indicates the potential use of creatinine as a quantitative population indicator. Additional research on the biodegradability of creatinine is needed because the prison setting was deliberately selected to minimize the potential for creatinine biodegradation. Chapter 4 addresses the data gap that exists on illicit drug transformation during in situ transit in sewers. The rates of in situ biodegradation have not yet been determined for conditions that are relevant to sewers, which include low to variable oxygen concentrations, the presence of a biofilm, and temperatures ≤ 20 °C. For this reason, two tracer tests were conducted in a 5 km stretch of sewer located near Zürich, Switzerland. The stable-isotope forms (deuterated) of cocaine and benzoylecgonine were injected into flowing wastewater and three locations up to 5 km downstream were sampled over time. Breakthrough curves were constructed from measurements of cocaine-d3 and benzoylecgonine-d3 concentration with time. The area under the curve (mass) was determined by integrating concentration over time. Benzoylecgonine-d3 was present in the injectate that should have only contained cocaine-d3; because the benzoylecgonine-d3 formation prior to injection is not known. The injected mass of cocaine-d3 did not decline over the 5 km distance. The observed mass of cocaine-d3 at 5 km was 10% greater than at 500 m, which indicates that the transformation of cocaine was not significant over the 1.5 h experiment. At 5 km downgradient, the apparent mass of benzoylecgonine-d3 had increased by 35% over that observed at 500 m. However, the apparent increase in benzoylecgonine-d3 mass was not accompanied by a corresponding loss of cocaine-d3. While uncertainty is apparent in the increase of both cocaine-d3 and benzoylecgonine-d3, the ratio of cocaine-d3/benzoylecgonine-d3 is subject only to analytical error because any errors associated with sampling and the integration of masses cancel out. The ratio of cocaine-d3/benzoylecgonine-d3 declined from 2.98 in the injectate to 1.66 at Location 3, which indicated a greater increase in benzoylecgonine-d3 relative to cocaine over the 5 km distance. Due to the benzoylecgonine-d3 that was present in the injectate, any biodegradation of cocaine-c3 to form benzoylecgonine-d3 could not be unambiguously distinguished. During the second tracer test in which benzoylecgonine-d3 was injected, the mass of benzoylecgonine-d3 did not significantly decline, which suggests that the apparent loss of benzoylecgonine-d3 during the cocaine-d3 test cannot be attributed to in-situ biodegradation. Overall, while uncertainty exists about the integrated masses for cocaine-d3 and benzoylecgonine-d3, the 5 km distance was too short in order to observe a significant loss of cocaine-d3 and formation of benzoylecgonine-d3. Recommendations for future research include conducting analysis on the injectate solution to ensure that only cocaine-d3 is introduced so that any formation of benzoylecgonine-d3 is readily apparent and quantifiable. In addition, the tracer tests should be repeated in a longer section of sewer to increase the residence time beyond 1.5 hr and degradation products of benzoylecgonine-d3 should be monitored including ecgonine and ecgonine methyl ester.
Graduation date: 2013
Access restricted to the OSU Community at author's request from Jan. 7, 2013 - Jan. 7, 2014

碩士
正修科技大學
工業工程與管理研究所
102
This study aims to improve the maximum warpage and ejection time of an injection molded plastic wheel. The methods applied in this study are the uniform design of experiments, mold flow analysis, Kriging surrogate modeling, compromise programming, and optimization. The process parameters to be improved are the 7 factors: the diameter of sprue in the lower end, the diameter of gate in the small end, the diameter of cross-section of runner, the temperature of cooling water, melt temperature, injection time, and packing pressure. The research process has eight steps: Step 1. The uniform design method is used to planning 16 experiments with 7 factors. Step 2. The plastics injection molding software Moldflow is employed to analyze the maximum warpage and ejection time for every experiment. Step 3. The Kriging surrogate modeling method is used to create the surrogate model of maximum warpage and the surrogate model of ejection time based on the input and output data of experiments. Step 4. The goal of minimizing the maximum warpage and the goal of minimizing the ejection time are synthesized into one single objective based on the compromise planning method. The single objective function is then minimized by the GRG nonlinear programming method. Step 5. The maximum warpage and ejection time under the optimal solution obtained in the previous step are evaluated again by Moldflow. Step 6. The optimal solution and the maximum warpage and ejection time under the optimal solution are added into the table of experiments. Step 7. Repeating step 3 to step 6 10 times to obtain 10 optimal solutions. From the 10 optimal solutions, one solution which has a good maximum warpage improvement rate and a good ejection time improvement rate is selected as the improved process condition. Step 8. Carrying out the factor sensitivity analysis and ranking factors. The results obtained in this study show that the maximum warpage can be decreased from 0.1247mm to 0.1151mm. The ejection time can be reduced from 10.76 seconds to 9.478 seconds. The diameter of sprue in the lower end and packing pressure can affect both the maximum warpage and ejection time. Reducing the diameter of sprue in the lower end and increasing the packing pressure can decrease the maximum warpage and ejection time, simultaneously. At last, to expand the availability of the surrogate models created in this study, this study applies HTML and Javascript language to embed the surrogate models into an interactive dynamic web page. By accessing the web page with a browser through the Internet, remote users can input the values of control factors and get the predicted values of maximum warpage and ejection time immediately.

碩士
正修科技大學
工業工程與管理研究所
101
This study aims to improve the warpage deformation and production time of an injection molded plastic spur gear. The methods applied in this study are the uniform design of experiemnts, mold flow analysis, Kriging surrogate modeling, and optimization algorithms.The process parameters to be improved are the diameter of sprue in the lower end, melt temperature, the diameter of sprue in the upper end, colling water temperature, the diameter of gate in the small end, injection time, and packing pressure. The layouts of cooling channels have three schemes:parallel channels in one side together with a circular channel, parallel channels in both sides together with a circular channel, and parallel channels in both sides with no circular channel.The flow of this research is as follows. Frist of all, a set of experiemnts with seven factors is planned based on the uniform design method for each layout of colling channels. Second, the warpage deformation and ejection time of the injection molded pastic spur gear is analyzed by Moldflow.Third, the maximum warpage deformation surrogate model and ejection time surrogate model are built based on the Kriging surrogate modeling method.Forth, a genetic algorithm and a SQP algorithm are used to solve the optimal solutions of process parameters minimizing the maximum warpage deformation surrogate model.Finally, at the optimal solutions, the moldflow software is applied again to measure the real values of maximum warpage deformation and ejection time to identify whether the optimal solutions determined via surrogate model can be the near-optimal solutions of the real problem. For the three layouts of colling channels, as long asthe uniform experiments are applied, the maximum warpage deformation can be reduced from 0.7542mm, 7399mm, 0.7403mmto 0.6728mm, 0.6662mm, 0.666mm and the ejection time can be reduced from 107.1 second, 102.2 second, 102.3 second to 91.54 second, 88.03 second, 88.17 second. After surrogate modeling and optimization,the maximum warpage deformation can be reduced further to 0.6635mm, 0.6652mm, 0.6555mm and the ejection time can be reduced further to 97.64 second, 91.52 second, 85.63 second. It can be found that the layout provided with parallel channels in both sides with no circular channel is the best one. Based on the results of factor sensitivity analysis, melt temperature is the most important factor for maximum warpage deformation and ejection time. A lower melt temperature will cause a lower maximum warpage deformation and ejection time.