Dissertations / Theses on the topic 'Through the resolution of problems'

PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
O problema de estimação pode ser entendido como um caso particular dos problemas inversos. Dadas observações da resposta de um sistema para certas causas, deseja-se estimar certas características do sistema. Essas características, em um sistema dinâmico, geralmente são representadas por parâmetros. Assim, para uma representação físico-matemática do sistema, dada uma excitação e observando a resposta, é possível obter uma estimação dos parâmetros. A estimação paramétrica é de grande importância e utilizada em diversas situações, desde experimentalistas, ao observar fenômenos no laboratório, até quem estuda o comportamento de setores sociais por amostras populacionais. A parte inicial desta dissertação apresenta uma breve introdução ao problema inverso do marco da estatística Bayesiana. Neste marco trata-se a estimação paramétrica como resultado da resolução de um problema inverso. Duas técnicas de estimação s ao deduzidas a partir da inferência estatística Bayesiana. A primeira delas, mínimos quadrados, coleta todos os dados e logo faz a estimação. A segunda, filtro de Kalman (e filtro de Kalman extendido), melhora o estado do conhecimento dos parâmetros a serem estimados a cada nova observação. Para a abordagem destas técnicas de estimação, de modo de poder compará-las, é apresentada a resolução analítica de um sistema harmônico de um e dois graus de liberdade. Por último, é apresentada uma modelagem de uma bancada experimental, em escala de laboratório, que emula uma coluna de perfura ção acoplada a um motor. Esta bancada foi desenvolvida para estudos de dinâmica torcional, na dissertação de mestrado de Bruno C. Cayres A., de modo que aqui só é de interesse a caracterização da mesma. As técnicas de estimação paramétrica são usadas de forma teórica, simulando os dados a partir de soluções analíticas para diferentes parâmetros da modelagem do motor e da coluna. Também usa-se medições feitas na bancada para estimar os parâmetros da modelagem, obtendo assim um conhecimento melhorado dos parâmetros envolvidos no sistema coluna-motor.
The estimation problem can be understood as a particular case of an inverse problem. Given observations of the response of a system, due to certain causes, one wants to estimate certain characteristics of the problem. These features, in a dynamic system, are usually represented by parameters. Thus, for a mathematical representation of the physical system, given an excitation and given the observing response, it is possible to give an estimation of the parameters. The parameter estimation is of great importance and used in countless situations, such as experimental obseration of a phenomena in the laboratory or even by those who study the behaviors social sectors by population samples. The initial part of this dissertation presents a brief introduction to the inverse problem the framework of the Bayesian statistics. In this context, the parametric estimation is a result of the resolution of an inverse problem. Two estimation techniques are derived from the Bayesian statistical inference. The first of these, least squares, collects all the data and then makes the estimation. The second, Kalman filter (and extended filter Kalman), improves the state of knowledge of the parameters to be estimated, with each new observation. To address these estimation techniques, in order to be able to compare them, presents the analytical resolution of a harmonious system of one and two degrees of freedom. Finally, it is presented a model for an experimental setup, in laboratory scale, which emulates a drillstring coupled to a motor. This experimental setup was developed to study the dynamic torsional and by the author of the dissertation of Bruno C. Cayres A., the mode that is of interest here only the characterization of it. These techniques are used for parameter estimation in theoretical way, simulating data from the analytical solutions, for different parameters involved in the column-motor modeling. Also, we use measurements obtained from the experimental setup to estimate the parameters of the column-motor model. Thereby, we obtain an improved knowledge of the parameters involved in the column-motor.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The present paper shows the results of a survey with 32 students from High School a Night class that is concomitant with the Vocational Education at Colégio Evangélico Panambi, from Panambi - RS. For this research that is qualitative were used as data collection the following instruments: questionnaires with the students, with the intention of doing a survey about their previous background related to the concept of function, a diagnosis test consisting of four activities relating to functions, a daily classroom and participant observation in which was reported all class events, as well as documents produced by students in resolutions of problems. This study intended to analyze the contribution of the Methodology of Teaching and Learning Evaluation through the Resolution of Problems for the construction of the concept of afim function by the High School students, for the application and development of the activities were followed the steps suggested by Onuchic and Allevato regarding the methodology of Problem Solving. Thus it is considered relevant to analyze the experiences of teaching specifically in this study, the Methodology of Teaching and Learning Math Evaluation, through the Resolution of Problems, particularly the concept of afim function. After the implementation of the activities and the results analyzed, it was noticed that the students had mainly difficulties regarding the interpretation of the statements of the problems proposed. However the collective work had a definitive role for carrying out the proposed activities and showed an extreme importance, without that, the results would not be the same. Also it was possible to verify during the development of the activities that the students have some difficulty in making written records of activities as well as the procedures used in the resolution of problems proposed.
Tem-se nesta dissertação o resultado de uma pesquisa realizada com 32 alunos de uma turma de 1º ano do Ensino Médio noturno que é concomitante com o ensino profissionalizante no Colégio Evangélico Panambi, de Panambi RS. Para a realização desta pesquisa de caráter qualitativo foram utilizados na coleta de dados os seguintes instrumentos: questionários com os alunos, com o intuito de fazer um levantamento acerca dos conhecimentos prévios relacionados ao conceito de função, um teste diagnóstico composto de quatro atividades referentes a funções, observação participante e diário de aula no qual foram relatados todos os acontecimentos ocorridos em classe, bem como documentos produzidos pelos alunos nas resoluções dos problemas. Nesta pesquisa pretendeu-se analisar a contribuição da Metodologia de Ensino-Aprendizagem-Avaliação através da Resolução de Problemas para a construção do conceito de função afim pelos alunos do ensino médio; para a aplicação e desenvolvimento das atividades foram seguidos os passos sugeridos por Onuchic e Allevato a respeito da metodologia de Resolução de Problemas. Assim considera-se relevante analisar de modo mais fundamentado as experiências de ensino e, nesta pesquisa, específicamente a Metodologia de Ensino-Aprendizagem-Avaliação de Matemática através da Resolução de Problemas, particularmente o conceito de função afim. Após a aplicação das atividades, e os resultados analisados, constatou-se que os alunos tinham dificuldades principalmente quanto à interpretação dos enunciados dos problemas propostos. Porém o trabalho coletivo teve um papel definitivo para a realização das atividades propostas e, demonstrou-se de extrema importância, sem o qual os resultados não seriam os mesmos. Também foi possível verificar durante o desenvolvimento das atividades que os alunos apresentam certa dificuldade em fazer registros escritos das atividades desenvolvidas bem como dos procedimentos utilizados na resolução dos problemas propostos. Com base nos resultados alcançados e nos depoimento dos alunos quanto às atividades, conclui-se que essa metodologia aproxima a matemática ao cotidiano do aluno, o que desperta maior interesse na realização das tarefas e consequentemente mais êxito na resolução das atividades.

In this thesis, I demonstrate how the numerous forms of oppression are grounded in a hierarchical and binary thinking that permeates racism and sexism and that is present throughout the feminist movement. It is this biased thinking that creates further divide among diverse social groups resulting in a foundation for justifying oppressive practices. I argue that the human rights framework is the best by which to defeat this problematic thinking, fostering a collectivity among disparate people and establishing a more appropriate footing upon which to face the problems of feminism. In the end, I claim that there must be a global commitment to end oppression that begins with educating people as to the unjustified harm created by biased and binary thinking and to the effectiveness of a human rights approach in eliminating any validation of oppression.

Thesis (M.A.)--Georgia State University, 2008.
Title from file title page. Andrew Jason Cohen, Christie Hartley, committee co-chairs; Peter Lindsay, committee members. Electronic text (55 p.) : digital, PDF file. Description based on contents viewed June 24, 2008. Includes bibliographical references (p. 54-55).

Controversies have existed for some time about cybernetics as a subject and difficulties have existed for students in obtaining an overview despite the fact that at some level several cybernetics concepts can be grasped by twelve year olds. An attempt is made to unpack the notion of a subject entity and to indicate how far elements in cybernetics conform to such a concept within a generally acceptable philosophy of science. Ambiguities and controversies among key themes of cybernetics are examined and resolutions offered. How far the nature of cybernetics is likely to create problems of understanding is discussed, along with approaches towards the empirical examination of how cybernetic ideas are understood. An approach to better understanding is formulated and used in an investigation of how and how effectively the concept of feedback is grasped by various groups. Suggestions are offered from the foregoing analysis as to the balance of problems within cybernetics and effective strategies for the future.

Customer problem is a common problem that needs to be handled in the company that provides support to their customer. Abundant data that it produced makes it inefficient to do it manually, which makes machine learning as an approach that could help to solve it. This project achieved a suitable approach of classifying a customer problem using text categorisation. This particular dataset is solvable when using Term Frequency-Inverse Document Frequency and one-hot encoding to generate the feature and use Logistic Regression as the classifier. Three measurement metrics, named F1 weighted score, Geometric Mean, and Indexed Balance Accuracy, was used to measure this imbalanced dataset.

Thesis (M.A.)--City University of Hong Kong, 2007.
"Master of Arts in arbitration and dispute resolution dissertation, City University of Hong Kong" Title from PDF t.p. (viewed on May 22, 2007) Includes bibliographical references.

Dans cette thèse, nous discutons de quatre scénarios d’application différents qui peuvent être largement regroupés dans le cadre plus large de l’analyse et du traitement d’images à haute résolution à l’aide de techniques d’apprentissage approfondi. Les trois premiers chapitres portent sur le traitement des images de télédétection (RS) captées soit par avion, soit par satellite à des centaines de kilomètres de la Terre. Nous commençons par aborder un problème difficile lié à l’amélioration de la classification des scènes aériennes complexes par le biais d’un paradigme d’apprentissage profondément faiblement supervisé. Nous montrons comment en n’utilisant que les étiquettes de niveau d’image, nous pouvons localiser efficacement les régions les plus distinctives dans les scènes complexes et éliminer ainsi les ambiguïtés qui mènent à une meilleure performance de classification dans les scènes aériennes très complexes. Dans le deuxième chapitre, nous traiterons de l’affinement des étiquettes de segmentation des empreintes de pas des bâtiments dans les images aériennes. Pour ce faire, nous détectons d’abord les erreurs dans les masques de segmentation initiaux et corrigeons uniquement les pixels de segmentation où nous trouvons une forte probabilité d’erreurs. Les deux prochains chapitres de la thèse portent sur l’application des Réseaux Adversariatifs Génératifs. Dans le premier, nous construisons un modèle GAN nuageux efficace pour éliminer les couches minces de nuages dans l’imagerie Sentinel-2 en adoptant une perte de consistance cyclique. Ceci utilise une fonction de perte antagoniste pour mapper des images nuageuses avec des images non nuageuses d’une manière totalement non supervisée, où la perte cyclique aide à contraindre le réseau à produire une image sans nuage correspondant a` l’image nuageuse d’entrée et non à aucune image aléatoire dans le domaine cible. Enfin, le dernier chapitre traite d’un ensemble différent d’images `à haute résolution, ne provenant pas du domaine RS mais plutôt de l’application d’imagerie à gamme dynamique élevée (HDRI). Ce sont des images 32 bits qui capturent toute l’étendue de la luminance présente dans la scène. Notre objectif est de les quantifier en images LDR (Low Dynamic Range) de 8 bits afin qu’elles puissent être projetées efficacement sur nos écrans d’affichage normaux tout en conservant un contraste global et une qualité de perception similaires à ceux des images HDR. Nous adoptons un modèle GAN multi-échelle qui met l’accent à la fois sur les informations plus grossières et plus fines nécessaires aux images à haute résolution. Les sorties finales cartographiées par ton ont une haute qualité subjective sans artefacts perçus
In this thesis, we discuss four different application scenarios that can be broadly grouped under the larger umbrella of Analyzing and Processing high-resolution images using deep learning techniques. The first three chapters encompass processing remote-sensing (RS) images which are captured either from airplanes or satellites from hundreds of kilometers away from the Earth. We start by addressing a challenging problem related to improving the classification of complex aerial scenes through a deep weakly supervised learning paradigm. We showcase as to how by only using the image level labels we can effectively localize the most distinctive regions in complex scenes and thus remove ambiguities leading to enhanced classification performance in highly complex aerial scenes. In the second chapter, we deal with refining segmentation labels of Building footprints in aerial images. This we effectively perform by first detecting errors in the initial segmentation masks and correcting only those segmentation pixels where we find a high probability of errors. The next two chapters of the thesis are related to the application of Generative Adversarial Networks. In the first one, we build an effective Cloud-GAN model to remove thin films of clouds in Sentinel-2 imagery by adopting a cyclic consistency loss. This utilizes an adversarial lossfunction to map cloudy-images to non-cloudy images in a fully unsupervised fashion, where the cyclic-loss helps in constraining the network to output a cloud-free image corresponding to the input cloudy image and not any random image in the target domain. Finally, the last chapter addresses a different set of high-resolution images, not coming from the RS domain but instead from High Dynamic Range Imaging (HDRI) application. These are 32-bit imageswhich capture the full extent of luminance present in the scene. Our goal is to quantize them to 8-bit Low Dynamic Range (LDR) images so that they can be projected effectively on our normal display screens while keeping the overall contrast and perception quality similar to that found in HDR images. We adopt a Multi-scale GAN model that focuses on both coarser as well as finer-level information necessary for high-resolution images. The final tone-mapped outputs have a high subjective quality without any perceived artifacts

Thesis (M.A.)--Georgia Southern University, 2009.
"A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Arts." Directed by Emilia Powell. ETD. Includes bibliographical references (p. 58-62)

J'ai étudié trois problèmes d'optimisation dans les graphes et les jeux combinatoires.Tout d'abord, les codes identifiants dans les graphes où les sommets font faces à des failles: les codes cherchent à repérer les failles pour les réparer. On s'est intéressé aux codes identifiants dans les graphes circulants en utilisant des plongements de ces graphes dans des grilles infinies.Ensuite, j'ai étudié le jeu de marquage de sommets et le jeu de coloration d'arêtes: ici deux joueurs se font face, le premier cherche à construire une coloration correcte (ou un marquage correct) et le deuxième cherche à l'en empêcher. Pour le jeu de marquage on s'est intéressé aux changements de stratégie gagnante lorsqu'on modifie le graphe. Pour le jeu de coloration d'arêtes on a donné une stratégie gagnante pour le premier joueur pourvu que le graphe considéré admette une certaine décomposition sur les arêtes. On améliore notamment des résultats sur les graphes planaires.Enfin j'ai étudié les jeux à tas purement de casse: deux joueurs à tour de rôle prennent un tas et le cassent en un certain nombre de tas non vides. On s'intéresse aux stratégies gagnantes lorsque les joueurs jouent sur un unique tas contenant n jetons. Ces jeux de pure casse semblent, à l'oeil nu, être réguliers. On a montré que c'est effectivement le cas pour certains et on a donné un test qui permet de déterminer la régularité cas par cas. Un seul cas ne semble pas correspondre à cette régularité: son comportement reste un mystère.En conclusion, je me suis intéressé à trois problèmes bilatéraux qui utilisent différentes méthodes et qui remplissent des propos différents dans le domaine de la combinatoire
I studied three optimization problems on graphs and combinatorial games.First, identifying codes were studied : vertices couteract faults. Identifying codes help locate the fault to repare it. We focused on circulant graphs by embedding them on infinite grids.Then, the marking and the coloring games were studied : two player games were one player wants to build something (a proper coloration or a proper marking) and the other wants to prevent the first player from doing so. For the marking game we studied the evolution of the strategy when modifying the graph. For the coloring game we defined a new edge-wise decomposition of graphs and we defined a new strategy on this decomposition that improves known results on planar graphs.In the end, I studied pure breaking games : two players take turns to break a heap of tokens in a given number of non-empty heaps. We focused on winning strategies for the game starting with a unique heap on n tokens. These games seem, on first sight, to be all regular : we showed this is the case for some of them and we gave a test to study one game at a time. Only one of these games does not seem to be regular, its behavior remains a mystery.To sum up, I studied three bilateral problems that use different methods and have different purposes in combinatorics

The measurement of topography is a key aspect of geomorphology research, and the prevalence of high resolution topographic data predominantly from Light Detection And Ranging (LiDAR) in the past decade has facilitated a revolution in the quantitative study of planetary surface processes. From this increased quality of data, many techniques have been developed to quantify processes occurring at diverse spatial and temporal scales; from the flow of material down a hill-slope to the uplift and subsequent erosion of mountain ranges. Such insights have identified signatures of processes imprinted on landscapes. These include physical processes such as wildfires and landslides, biological processes such as animal burrowing and tree throw, in addition to tectonic uplift and large scale sediment transport. These signatures are observed in both the morphology of hill-slopes and their connection to the channel network, thereby allowing measures of topography to provide quantitative measures of the rates of processes shaping the Earth’s surface. This thesis is concerned with the development and application of reproducible topographic analysis techniques, to yield new insights into hill-slope sediment transport and to provide accurate metrics for quantifying hill-slope properties, including hill-slope length (LH) and relief (R). The measurement of hill-slope length can be performed through the inversion of drainage density, or the analysis of slope-area plots. However, in Chapter 3 I present a method which quantifies the length of hill-slopes through the generation of hill-slope flow paths. The flow path method is shown to be the most reliable of these methods, and is able to provide measurements of the properties of individual hill-slopes, rather than the basin or landscape averaged techniques commonly employed. The topographic predictions of the LH-R relationship of the nonlinear sediment flux law, stating that the rate of sediment transport is nonlinearly dependent on hill-slope gradient, are also tested and contrasted with the predictions of a linear sediment flux law. This provides the first purely topography based test of a sediment flux law. Through the fitting of a prediction of the nonlinear flux derived model to these measurements of hill-slope length and relief, the critical gradient of each landscape, a key parameter in the nonlinear sediment flux law, is also constrained. A nondimensional framework for erosion rate and relief, which allows the comparison of hill-slopes with differing properties in order to identify landscape transience is presented in Chapter 4. This analysis technique builds upon the work performed in Chapter 3, utilizing similar measurements of hill-slope properties, including hill-slope length and relief. The software produced alongside this chapter is shown to reproduce the results of previous studies which have employed this technique. The method is employed on a new landscape in Coweeta, North Carolina where subtle evidence of topographic decay is presented, consistent with models of Miocene topographic rejuvenation in this location. A detailed sensitivity analysis of the technique is performed, highlighting the need for careful parameterization of any analysis, to ensure meaningful results. This method is also employed to estimate an average critical gradient for each landscape, presenting more evidence building upon the evidence presented in Chapter 3 that a broad range of critical gradients exist for any given landscape. The work presented in Chapter 5 attempts to constrain the limits of the geomorphic analyses presented in the previous chapters, when they are applied to low resolution topographic data. A series of topographic datasets are generated at resolutions ranging from 1 to 30 meters upon which topographic analyses are performed. I test two common channel extraction algorithms and find that a simple geometric method, which identifies tangential curvature thresholds in the landscape, provides a more accurate representation of the channel network in low resolution topographic data than a process based method which identifies the topographic signature of channel initiation. The measurement of curvature is also evaluated, and alongside the estimation of diffusivity, is shown to be sensitive to data resolution, however landscape properties also exhibit a strong control on these measurements, where the larger scale curvature signal of Gabilan Mesa, California is more robust than the sharp ridgelines of Santa Cruz Island, California. Finally, the techniques developed in Chapter 3 to measure hill-slope length and relief are tested and are shown to be robust at grid sizes up to 30 meters, with the caveat that an accurate channel network can be constrained.

Can a first-line supervisor improve worker performance? First-line supervisors at a facility of a manufacturing company volunteered to learn performance improvement principles and be coached in applying those principles in order to solve performance problems in the workplace. The researcher continued coaching and evaluating the performance of the first-line supervisors as the volunteers utilized action research methodology to improve worker performance. While solving performance problems, the volunteers used a job aid specifically designed to guide the first-line supervisor in solving performance problems, improving the job aid as a result of usage. Each of the first-line supervisors, prior to volunteering, had some experience as a supervisor, ranging from one year to 20 years, but had not been prepared to be a supervisor prior to assuming the position and had not been trained in performance improvement after becoming a supervisor. In solving each performance problem, the first-line supervisor analyzed performance of a worker or group of workers to determine the performance gap for the problem, identified the cause of the problem, chose an intervention to improve performance, implemented the intervention, and evaluated all of the actions taken to determine if further action was needed to improve performance. Some performance problems were solved with one intervention and others required multiple interventions to find the most effective intervention to solve the problem. Each first-line supervisor used the job aid to guide, as well as document, actions taken to solve performance problems. Each first-line supervisor also contributed to improvement in the job aid resulting from usage. Findings resulting from observation, interview, and the comments of the volunteer first-line supervisors were that: (a) learning was transferred to application by actually solving performance problems, (b) the job aid was useful in guiding first-line supervisors in solving problems, and (c) action research, in addition to being easily understood by the supervisors, facilitated the solution of problems by providing a framework for action in solving performance problems. Further research is needed in applying the action research methodology in other organizations with a larger sample of first-line supervisors, in different locations, with different missions and goals.

Optimisation and related techniques are well suited to clearly defined problems involving systems that can be accurately simulated, but not to tasks in which the phenomena in question are highly complex or the problem ill-defined. These latter are typical of architecture and particularly creative design tasks, which therefore currently lack viable computational tools. It is argued that as design teams and construction projects of unprecedented scale are increasingly frequent, this is just where such optimisation and communication tools are most needed. This research develops a method by which to address complex design problems, by using inductive machine learning from example precedents either to approximate the behaviour of a complex system or to define objectives for its optimisation. Two design domains are explored. A structural problem of the optimisation of stiffness and mass of fine scale, modular space frames has relatively clearly defined goals, but a highly complex geometry of many interconnected members. A spatial problem of the layout of desks in the workplace addresses the social relationships supported by the pattern of their arrangement, and presents a design situation in which even the problem objectives are not known. These problems are chosen to represent a range of scales, types and sources of complexity against which the methods can be tested. The research tests two hypotheses in the context of these domains, relating to the simulation of a system and to communication between the designer and the machine. The first hypothesis is that the underlying structure and causes of a system’s behaviour must be understood to effectively predict or simulate its behaviour. This hypothesis is typical of modelling approaches in engineering. It is falsified by demonstrating that a function can be learned that models the system in question—either optimising of structural stiffness or determining desirable spatial patterns—without recourse to a bottom up simulation of that system. The second hypothesis is that communication of the behaviour of these systems to the machine requires explicit, a priori definitions and agreed upon conventions of meaning. This is typical of classical, symbolic approaches in artificial intelligence and still implicitly underlies computer aided design tools. It is falsified by a test equivalent to a test of linguistic competence, showing that the computer can form a concept of, and satisfy, a particular requirement that is implied only by ostensive communication by examples. Complex, ill-defined problems are handled in practice by hermeneutic, reflective processes, criticism and discussion. Both hypotheses involve discerning patterns caused by the complex structure from the higher level behaviour only, forming a predictive approximation of this, and using it to produce new designs. It is argued that as these abilities are the input and output requirements for a human designer to engage in the reflective design process, the machine can thus be provided with the appropriate interface to do so, resulting in a novel means of interaction with the computer in a design context. It is demonstrated that the designs output by the computer display both novelty and utility, and are therefore a potentially valuable contribution to collective creativity.

This thesis consists of a compendium of five works that illustrate the utilization of selected mathematical methods to solve specific chemical engineering problems. Hence, the thesis is intended to cover both, a review of fundamental mathematical procedures for the solution of models raised from chemical phenomena, and a demonstration of their effectiveness to obtain useful novel significant results. The opening paper explores diverse global optimization algorithms to adjust both kinetic constants and the binary interaction parameters (BIPs) for the Peng-Robinson equation of state to the experimental data. Those parameters are essential to determine the model raised from the supercritical transesterification of triolein with methanol to produce biodiesel, with CO2 as cosolvent, consisting of three reversible reaction in series. Here, a novel model merging the ordinary differential equations system raised from kinetic mechanism and the time-dependent thermodynamic state of the complex mixture is presented for diverse operating conditions. Among all results obtained, novel binary interaction coefficients for the intermediate reaction species (dioleins and monooleins) highlight. The second and fourth papers included in this thesis are aimed at the study of lanolin extraction from raw wool, using 5% ethanol in CO2. The former explores solid lanolin extraction under near-critical conditions by means of a mass-transfer model based on the shrinking-core concept, while the latter is addressed at the liquid lanolin supercritical extraction. Both models result in a partial differential equations (PDEs) system determined by the solubility of multiphasic lanolin, Henry-type partition coefficient and the lanolin mass transfer coefficient. Hence, in each paper the raised PDEs system is solved through a different method: in the second paper orthogonal collocation method is employed, while in the fourth paper finite differences method is used combined with the numerical integration of an expression previously obtained by means of the Laplace transform. Finally, an optimization procedure is used in order to fit the extraction parameters to the experimental data, achieving coherent results that agree well with those previously reported. Between the cases exposed, liquid lanolin extraction is significantly complex to model because of the diffusion phenomena that may occur inside the two lanolin fraction mixture added to the diffusion of solvent in the interphase. Therefore, in the third work a nonlinear autoregressive exogenous neural network model is designed to predict the outcoming extracted fraction of lanolin at diverse temperatures, pressures, solvent mass flow rates, wool packing densities and times. The problem with the scarce data available for training of the neural network is overcome by augmenting experimental data using an empirical Weibull function, which correctly predicts the lanolin breakthrough at the extractor exit. This hybrid Weibull - Neural Network algorithm results in a low prediction error and conform a powerful tool for optimizing operating conditions, proved by the fast convergence of genetic algorithm procedure. This thesis closes with Molecular Dynamics simulations for peptide-folding studies, followed by a Principal Component Analysis (PCA) and clustering analysis to understand the Free Energy Landscape of the peptide (FEL). Those methods are aimed at assessing the conformational profile of bombesin, a peptide with interest in drug design as a possible novel agonist and/or antagonist in the fight against cancer. Results suggest that the peptide adopts mainly helical structures at the C-terminus and, to a lesser extent, hairpin turn structures at the N-terminus. Those results agree with those available from NMR in a 2,2,2-trifluoroethanol/water (30% v/v), and point out a suitable a-helix conformation for binding where Trp8 and His12 interaction has a significant role.
Aquesta tesi consta d'un compendi de cinc treballs que il·lustren la utilització de mètodes matemàtics per resoldre problemes específics d'enginyeria química. Per tant, la tesi està destinada a ser una revisió dels procediments matemàtics fonamentals per a la solució de models derivats de fenòmens químics i, a més, una demostració de la seva efectivitat per obtenir resultats útils i innovadors. L'article que obre la tesi explora diferents algoritmes d'optimització global per ajustar tant les constants cinètiques com el Paràmetres d'Interacció Binària (PIB) per a l'equació d'estat de Peng Robinsos a les dades experimentals. Aquests paràmetres són essencials per determinar el model derivat de la transesterificació supercrítica de la trioleïna amb metanol per produir biodièsel, amb CO2 com a cosolvent, que consisteix en tres reaccions reversibles en sèrie. Aquí, es presenta un nou model que fusiona el sistema d'EDOs derivat del mecanisme cinètic i l'estat termodinàmic de la barreja per a condicions de funcionament diverses. Entre tots els resultats obtinguts, destaquen els nous PIBs trobats per a les espècies de reacció intermèdies. El segon i quart treball inclosos en aquesta tesi estan destinats a l'estudi de l'extracció de lanolina de llana crua amb 5% d'etanol en CO2. El primer explora l'extracció de lanolina sòlida en condicions gairebé crítiques mitjançant un model de transferència de massa basat en el concepte del nucli minvant, mentre que el segon s'adreça al cas de l'extracció supercrítica de lanolina líquida. Ambdós models donen com a resultat un sistema d'EDPs determinat per la solubilitat de la lanolina multifàsica, el coeficient de partició de Henry i el coeficient de transferències de massa. Per tant, a cada article el sistema d'EDPs obtingut es resol mitjançant un mètode diferent: en el article s'utilitza un mètode de col·laboració ortogonal, mentre que en el quart s'utilitza el mètode de diferències finites combinat amb la integració numèrica d'una expressió obtinguda mitjançant la Transformada de Laplace. Finalment, es porta a terme una optimització per ajustar els paràmetres d'extracció a les dades experimentals, aconseguint resultats coherents que coincideixen amb els reportats anteriorment. Entre els casos expotsats, l'extracció de lanolina líquida és significativament complexa de modelar a causa dels fenòmens de difusió que es poden produir a l'interior de les dues fraccions de lanolina a més de la difusió del dissolvent en la interfase. Per tant, en el tercer treball es dissenya un model de xarxa neuronal exògena no lineal autoregressiva per predir la fracció extreta de lanlina a diverses temperatures, pressions, cabals de dissolvent, densitats d'empaquetament i temps. El problema derivat de l'escassetat de dades disponibles per a l'entrenament de la xarxa neuronal es supera amb l'augment d'aquestes mitjançant una funció de Weibull empírica, que prediu correctament l'avanç de la lanolina a la sortida de l'extractor. Aquest algoritme híbrid Weibull - xarxa neuronal resulta en un baix error de predicció i conforma una potent eina per optimitzar les condicions operatives, demostrada per la ràpida convergència de l'algoritme genètic utilitzat. Aquesta tesi tanca amb simulacions de Dinàmica Molecular per a l'estudi del plegament de pèptids seguint d'un Anàlisi de Components Principals (ACP) i del "clustering" per a l'anàlisi del Paisatge d'Energia Lliure (PEL). L'objectiu és avaluar el perfil conformacional de la bombesina, un pèptid amb interès en el disseny de fàrmacs com a possible nou agonista i/o antagonista en la lluita contra el càncer. Els resultats suggereixen que el pèptid adopta estructures helicoïdals principalment al extrem C, i també en menor mesura estructures de forquilla al extrem N. Aquests resultats coincideixen amb els disponibles de RMN en 2,2-trifluoroetanol/aigua (30% v/v) i indiquen una conformació d’hèlix a adequada per a la unió on la interacció Trp8 i His12 té un paper important.

Cette thèse s’intéresse à trouver des solutions informatiques à certains problèmes de l’optimisation combinatoire, à savoir les problèmes de tournées de véhicules. Elle aborde les problèmes de Transport A la Demande (TAD). L’objectif principal visé dans cette thèse fait appel à certaines approches exactes et certaines approches méta-heuristiques pour résoudre des problèmes d’optimisation multi-objective de Transport A la Demande avec plusieurs véhicules. En effet, nos principaux objectifs de recherche consistent à : -I) Résoudre un problème multi-objectif de Transport A La Demande multi-véhicules basé sur la qualité de service ; - II) Résoudre un autre problème de Transport A la Demande multi-objectifs multi-véhicules. Ce problème traite un cas spécifique et qui consiste à l’application de ce problème aux domaines de l’Hospitalisation A Domicile (HAD). Nous avons appliqué des algorithmes exacts de "Branch and Bound" et des méthodes méta-heuristiques telles que l’algorithme évolutionnaire "Algorithme Génétique" et l’algorithme de "Colonie de Fourmis" pour apporter des solutions efficaces à ces différents problèmes. Un ensemble de résultats numériques est présenté pour chacune de ces méthodes pour montrer leurs capacités de produire des solutions de haute qualité en temps de calcul raisonnables
This thesis focuses on finding computer science solutions for some combinatorial optimization problems, namely Vehicle Routing Problems (VRP). The thesis addresses the Dial A Ride Problems (DARP). Its main objective is to use some exact and meta-heuristics approaches to solve multi-objective optimization of Dial A Ride Problem with multi-vehicles. Hence, our main research aims are : - I)Solve a multi-objective Dial A Ride Problem with multi-vehicles based on quality of service, this problem treats a general case ; - II) Solve another multi-objective Dial A Ride Problem with multi-vehicles, this problem deals with a specific case which is an application of the Dial A Ride Problem in Home Health Care (HHC). We have also applied exact algorithms "Branch and Bound" and meta-heuristic algorithms such as evolutionary algorithms "Genetic Algorithm" and "Ant Colony" algorithm to provide effective solutions to these different problems. A set of numerical results are presented for each of these methods. Our results show that they produce high quality solutions in a reasonable execution time for all the treated problems

Thesis (M.S.)--Central Connecticut State University, 2000.
Thesis advisor: Ron Cassella. " ... in partial fulfillment of the requirements for the degree of Master of Science in Teacher Education." Includes bibliographical references (leaves 96-98).

It is now well established that the overall mechanical properties of a wide variety of tissues can be described by the cumulative nanomechanical properties of each of the individual constituent proteins. However, on a deeper, atomistic level, it is far less understood how the chemical reactivity of the individual chemical bonds forming the protein’s architecture can tune its nanomechanics. The amino acid cysteine is unique among all the protein amino acids due to its reactive sulfhydryl group. The particular chemical properties of the sulfur atom enable cysteine to exhibit a wide range of oxidation states, resulting in a rich and varied chemical reactivity that spans from the formation of organo-metallic bonds when coordinating a plethora of metal ions to the formation of the highly covalent and mechanically rigid disulfide bonds. It is therefore tempting to speculate that the incorporation of an individual cysteine residue into a protein sequence is a natural strategy for modulating chemical reactivity, mostly through post-translational modifications, with knock-on effects for protein mechanics. In this thesis work I employ single molecule force spectroscopy AFM to investigate how the different chemical reactivity of cryptic cysteines affects the folding and the nanomechanical properties of individual proteins. Firstly, I characterize the mechanical stability of the copper-thiolate bond in the metalloproteins azurin and plastocyanin. Furthermore, I use a constant force approach to probe two chemically distinct strategies to achieve non-enzymatic disulfide bond formation within the context of oxidative folding; through a transient sulfenic acid species or through the creation of a mixed disulfide species between a protein cysteine and a low molecular weight thiol. Altogether this work highlights that subtle adjustments to the chemical reactivity of a single thiol-bond within a protein, has unanticipated yet profound effects on the overall protein nanomechanics.

Compassion is often misunderstood. To live with compassion does not mean to give up one’s own well-being or to jeopardize the well-being of her family in order to serve the needs of others. Compassion means one must first take care of herself before she is able to tend to another. True compassion can exist only within the framework of well-balanced psychology or even-mindedness. It takes healthy self-esteem to realize one’s own limits and set clear and direct boundaries to protect those limits. Compassion means being deeply human and at the same time honoring one’s self and others.

Compassion, like muscle memory and rote memorization, is cultivated through practice. The current research from the field of neuroscience interprets compassion as a learned behavior as well as delineating that meditation is one of the most powerful tools for cultivating compassion and other balanced neurological states of being.

If we cultivated meditation, as we do reading and writing, as a part of the educational process for children from toddlers, through higher education, would that, in time change, what seems to be our addiction to the Ares archetype—war? At the very least, some students will see more compassionately, relate to life with more empathy, meet challenges with more optimism, and live with a greater sense of well-being and resilience. At best most of our children will grow up with these life affirming qualities that have power beyond measure to heighten the collective to live in a more peaceful state of consciousness.

This dissertation discusses the relationship between compassion and peace. As humanity becomes more compassionate, peace becomes a more viable state.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.
Includes bibliographical references (p. 37-38).
Real-world applications, such as diagnosis and embedded control, are increasingly being framed as OpSAT problems - problems of finding the best solution that satisfies a formula in propositional state logic. Previous methods, such as Conflict-directed A*, solve OpSAT problems through a weak coupling of A* search, used to generate optimal candidates, and a DPLL-based SAT solver, used to test feasibility. This paper achieves a substantial performance improvement by introducing a tightly coupled approach, Clause-directed A * (CIA *). ClA* simultaneously directs the search towards assignments that are feasible and optimal. First, satisfiability is generalized to state logic by unifying the DPLL satisfiability procedure with forward checking. Second, optimal assignments are found by using A* to guide variable splitting within DPLL. Third, search is directed towards feasible regions of the state space by treating all clauses as conflicts, and by selecting only assignments that entail more clauses. Finally, ClA* climbs towards the optimum by using a variable ordering heuristic that emulates gradient search. Empirical experiments on real-world and randomly-generated instances demonstrate an order of magnitude increase in performance over Conflict-directed A*.
by Robert J. Ragno.
M.Eng.

Modern machine learning methods are dependent on active optimization research to improve the set of methods available for the efficient and effective extraction of information from large datasets. This, in turn, requires an intense and rigorous study of optimization methods and their possible applications to crucial machine learning applications in order to advance the potential benefits of the field. This thesis provides a study of several modern optimization techniques and supplies a mathematical inquiry into the effectiveness of homotopy methods to attack a fundamental machine learning problem, effective clustering under constraints. The first part of this thesis provides an empirical survey of several popular optimization algorithms, along with one approach that is cutting-edge. These algorithms are tested against deeply challenging real-world problems with vast numbers of local minima, and compares and contrasts the benefits of each when confronted with problems of different natures. The second part of this thesis proposes a new homotopy map for use with constrained clustering problems. This thesis explores the connections between the map and the problem, providing several theorems to justify the use of the map and making use of modern homotopy tracking software to compare an optimization that employs the map with several modern approaches to solving the same problem.
Ph. D.

This thesis explores what UK community pharmacists experience as ethical problems in their work, how they try to resolve such problems and how the community pharmacy setting may be of influence. Utilising existing normative ethical theories, but acknowledging the status of empirical ethics research and also the social context of ethical problems, semi-structured interviews were conducted with a purposive sample of twenty three community pharmacists from the north of England, UK. It was found that pharmacists encountered ethical problems in the routine minutiae of dispensing prescriptions and medicines sales. Ethical problems often involved legal and procedural concerns and could be distinguished from philosophical dilemmas and many pharmacists understood law and ethics synonymously. Ethical passivity emerged as a description of pharmacists who were ethically inattentive, displayed legalistic self-interest and failed to act ethically. Ethical reasoning was often incomplete and involved appeals to consequences, the golden rule, common sense and religious faith. Some pharmacists were ethically active and sensitive to ethical issues and experienced ethical doubt and uncertainty. The code of ethics and the advice of professional bodies were not considered helpful. The community pharmacy setting precipitated ethical problems and was inimical to ethical practice since pharmacists' relative isolation from others precluded ethical discussion and relationships; pharmacists' subordination to doctors precipitated problems and vitiated ethical responsibility; routinization of pharmacists' work meant difficult ethical situations could be avoided. The findings of this thesis raise questions as to how pharmacists can be effectively educated in ethical issues at an under- and post-graduate level; how values can be adequately transmitted within the profession given the ineffectiveness of the code of ethics; whether pharmacists are ethically prepared for new primary care roles; and whether isolation and subordination may be ethically problematic in healthcare more generally.

In this thesis, we will be concerned with Kant's philosophy of beauty and with a particular area of interest which is of great importance to any practical theory of aesthetics: dispute. If one judges something to be beautiful - if one makes a judgment of taste, and we seek to persuade others to our conviction, then how can we go about doing this? We shall discover that Kant's theory provides an interesting account of how disputes over taste can take place: an account which is informative for the way in which we conduct aesthetics today.

The history of oil well engineering applications has revealed that the frequent operational problems are still common in oil well practice. Well blowouts, stuck pipes, well leakages are examples of the repeated problems in the oil well engineering industry. The main reason why these unwanted problems are unavoidable can be the complexity and uncertainties of the oil well processes. Unforeseen problems happen again and again, because they are not fully predictable, which could be due to lack of sufficient data or improper modelling to simulate the real conditions in the process. Traditional mathematical models have not been able to totally eliminate unwanted oil well problems because of the many involved simplifications, uncertainties, and incomplete information. This research work proposes a new approach and breakthrough for overcoming these challenges. The main objective of this study is merging two scientific fields; artificial intelligence and petroleum engineering in order to implement a new methodology.

Case-Based Reasoning (CBR) and Model-Based Reasoning (MBR), two branches of the artificial intelligence science, are applied for solving complex oil well problems. There are many CBR and MBR modelling tools which are generally used for different applications for implementing and demonstrating CBR and MBR methodologies; however, in this study, the Creek system which combines CBR and MBR has been utilized as a framework. One specific challenging task related to oil well engineering has been selected to exemplify and examine the methodology. To select a correct candidate for this application was a challenging step by itself. After testing many different issues in the oil well engineering, a well integrity issue has been chosen for the context. Thus, 18 leaking wells, production and injection wells, from three different oil fields have been analysed in depth. Then, they have been encoded and stored as cases in an ontology model given the name Wellogy.

The challenges related to well integrity issues are a growing concern. Many oil wells have been reported with annulus gas leaks (called internal leaks) on the Norwegian Continental Shelf (NCS) area. Interventions to repair the leaking wells or closing and abandoning wells have led to: high operating cost, low overall oil recovery, and in some cases unsafe operation. The reasons why leakages occur can be different, and finding the causes is a very complex task. For gas lift and gas injection wells the integrity of the well is often compromised. As the pressure of the hydrocarbon reserves decreases, particularly in mature fields, the need for boosting increases. Gas is injected into the well either to lift the oil in the production well or to maintain pressure in the reservoir from the injection well. The challenge is that this gas can lead to breakdown of the well integrity and cause leakages. However, as there are many types of leakages that can occur and due to their complexity it can be hard to find the cause or causal relationships. For this purpose, a new methodology, the Creek tool, which combines CBR and MBR is applied to investigate the reasons for the leakages. Creek is basically a CBR system, but it also includes MBR methods.

In addition to the well integrity cases, two complex cases (knowledge-rich cases) within oil well engineering have also been studied and analysed through the research work which is part of the PhD. The goal here is to show how the knowledge stored in two cases can be extracted for the CBR application.

A model comprising general knowledge (well-known rules and theories) and specific knowledge (stored in cases) has been developed. The results of the Wellogy model show that the CBR methodology can automate reasoning in addition to human reasoning through solving complex and repeated oil well problems. Moreover, the methodology showed that the valuable knowledge gained through the solved cases can be sustained and whenever it is needed, it can be retrieved and reused. The model has been verified for unsolved cases by evaluating case-matching results. The model gives elaborated explanations of the unsolved cases through the building of causal relationships. The model also facilitates knowledge acquisition and learning curves through its growing case base.

The study showed that building a CBR model is a rather time-consuming process due to four reasons:

1. Finding appropriate cases for the CBR application is not straightforward

2. Challenges related to constructing cases when transforming reported information to symbolic entities

3. Lack of defined criteria for amount of information (number of findings) for cases

4. Incomplete data and information to fully describe problems of the cases at the knowledge level

In this study only 12 solved cases (knowledge-rich cases) have been built in the Wellogy model. More cases (typically hundreds for knowledge-lean cases and around 50 for knowledge-rich cases) would be required to have a robust and efficient CBR model. As the CBR methodology is a new approach for solving complex oil well problems (research and development phase), additional research work is necessary for both areas, i.e. developing CBR frameworks (user interfaces) and building CBR models (core of CBR). Feasibility studies should be performed for implemented CBR models in order to use them in real oil field operations. So far, the existing Wellogy model has showed some benefits in terms of; representing the knowledge of leaking well cases in the form of an ontology, retrieving solved cases, and reusing pervious cases.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 1999.
Includes bibliographical references (leaves 102-109).
by Abby Knickerbocker.
M.Eng.

The purpose of the present investigation was to determine what professional and personal problems elementary-school teachers face during their initial years of teaching and how they cope with or solve these problems. Beginning teachers abandon the teaching profession at alarming rates causing grave financial burdens to school divisions, schools, and tax payers. The phenomenon has also contributed to the current teacher shortages in particular subject areas and certain geographic locations. Many teachers who left the profession before their fifth year of professional teaching reported the problems associated with teaching as primary reasons for their exodus. Qualitative in-depth interviews were conducted with six in-service elementary teachers. The interviews were conducted in three parts. All of the six participants were between their fifth and tenth year of teaching, and they all taught at the elementary level. The results indicated that they had problems with (a) personal issues and life experiences, (b) school curricula, (c) children with special needs, (d) differentiation of instruction, (e) discipline, (f) workload and time management, (g) parents, (h), student poverty and studentsâ home issues, (j) relationships with students, (k) teacher training, and (l) administration. The participants coped with these problems by using pattern matching indicating that their own life experiences and backgrounds had significant roles in their problem-solving processes. Recommendations are made for preservice and beginning in-service teachers to focus on their educational experiences and biographical information to recall relevant information that will help them to cope with and solve professional problems.
Ph. D.

Les différentes modalités d’imagerie par ondes présentent chacune des limitations en termes de résolution ou de contraste. Dans ce travail, nous modélisons l’imagerie ultrasonore ultrarapide et présentons des méthodes de reconstruction qui améliorent la précision de l’imagerie ultrasonore. Nous introduisons deux méthodes qui permettent d’augmenter le contraste et de mesurer la position super-résolue et la vitesse dans les vaisseaux sanguins. Nous présentons aussi une méthode de reconstruction des paramètres microscopiques en tomographie d’impédance électrique en utilisant des mesures multifréquence et en s’aidant de la théorie de l’homogénéisation
Different modalities in wave imaging each present limitations in terms of resolution or contrast. In this work, we present a mathematical model of the ultrafast ultrasound imaging modality and reconstruction methods which can improve contrast and resolution in ultrasonic imaging. We introduce two methods which allow to improve contrast and to locate blood vessels belowthe diffraction limit while simultaneously estimating the blood velocity. We also present a reconstruction method in electrical impedance tomography which allows reconstruction of microscopic parameters from multi-frequency measurements using the theory of homogenization

In the field of medical image analysis, ultrasound is a core imaging modality employed due to its real time and easy-to-use nature, its non-ionizing and low cost characteristics. Ultrasound imaging is used in numerous clinical applications, such as fetus monitoring, diagnosis of cardiac diseases, flow estimation, etc. Classical applications in ultrasound imaging involve tissue characterization, tissue motion estimation or image quality enhancement (contrast, resolution, signal to noise ratio). However, one of the major problems with ultrasound images, is the presence of noise, having the form of a granular pattern, called speckle. The speckle noise in ultrasound images leads to the relative poor image qualities compared with other medical image modalities, which limits the applications of medical ultrasound imaging. In order to better understand and analyze ultrasound images, several device-based techniques have been developed during last 20 years. The object of this PhD thesis is to propose new image processing methods allowing us to improve ultrasound image quality using postprocessing techniques. First, we propose a Bayesian method for joint deconvolution and segmentation of ultrasound images based on their tight relationship. The problem is formulated as an inverse problem that is solved within a Bayesian framework. Due to the intractability of the posterior distribution associated with the proposed Bayesian model, we investigate a Markov chain Monte Carlo (MCMC) technique which generates samples distributed according to the posterior and use these samples to build estimators of the ultrasound image. In a second step, we propose a fast single image super-resolution framework using a new analytical solution to the l2-l2 problems (i.e., $\ell_2$-norm regularized quadratic problems), which is applicable for both medical ultrasound images and piecewise/ natural images. In a third step, blind deconvolution of ultrasound images is studied by considering the following two strategies: i) A Gaussian prior for the PSF is proposed in a Bayesian framework. ii) An alternating optimization method is explored for blind deconvolution of ultrasound.

L’imagerie chimique permet d’accéder à la distribution spatiale des espèces chimiques. Nous distinguerons dans cette thèse deux types d’images différents: les images spatiales-temporelles et les images spatiales-spectrales.La microscopie de fluorescence super-résolue a commencé avec un faible nombre de fluorophores actifs par image. Actuellement, ça a évolué vers l’imagerie en haute densité qui requiert de nouvelles façons d’analyse. Nous proposons SPIDER, une approche de déconvolution par moindres carrés pénalisés. La considération de plusieurs pénalités permet de traduire les propriétés des émetteurs utilisés dans l'imagerie de fluorescence super-résolue. L'utilisation de cette méthode permet d'étudier des changements structuraux et morphologiques dans les échantillons biologiques. La méthode a été appliquée à l’imagerie sur cellules vivantes d’une cellule HEK-293T encodée par la protéine fluorescente DAKAP-Dronpa. On a pu obtenir une résolution spatiale de 55nm pour un temps d’acquisition de 0.5s.La résolution d'images hyperspectrales avec MCR-ALS fournit des informations spatiales et spectrales des contributions individuelles dans le mélange. Néanmoins, le voisinage des pixels est perdu du fait du dépliement du cube de données hyperspectrales sous forme d’une matrice bidirectionnelle. L’implémentation de contraintes spatiales n’est donc pas possible en MCR-ALS. Nous proposons une approche alternative dans laquelle une étape de repliement/dépliement est effectuée à chaque itération qui permet d’ajouter des fonctionnalités spatiales globales à la palette des contraintes. Nous avons développé plusieurs contraintes et on montre leur application aux données expérimentales
Besides the chemical information, chemical imaging also offers insights in the spatial distribution of the samples. Within this thesis, we distinguish between two different types of images: spatial-temporal images (super-resolution fluorescence microscopy) and spatial-spectral images (unmixing). In early super-resolution fluorescence microscopy, a low number of fluorophores were active per image. Currently, the field evolves towards high-density imaging that requires new ways of analysis. We propose SPIDER, an image deconvolution approach with multiple penalties. These penalties directly translate the properties of the blinking emitters used in super-resolution fluorescence microscopy imaging. SPIDER allows investigating highly dynamic structural and morphological changes in biological samples with a high fluorophore density. We applied the method on live-cell imaging of a HEK-293T cell labeled with DAKAP-Dronpa and demonstrated a spatial resolution down to 55 nm and a time sampling of 0.5 s. Unmixing hyperspectral images with MCR-ALS provides spatial and spectral information of the individual contributions in the mixture. Due to loss of the pixel neighborhood during the unfolding of the hyperspectral data cube to a two-way matrix, spatial information cannot be added as a constraint during the analysis We therefore propose an alternative approach in which an additional refolding/unfolding step is performed in each iteration. This data manipulation allows global spatial features to be added to the palette of MCR-ALS constraints. From this idea, we also developed several constraints and show their application on experimental data

Thesis (M.S.)--University of Akron, Dept. of Mathematics, 2005.
"August, 2005." Title from electronic thesis title page (viewed 11/28/2005) Advisor, Dmitry Golovaty; Faculty Readers, Eric Wright, Curtis B. Clemons; Associate Department Chair, Timothy S. Norfolk; Dean of the College, Charles B. Monroe; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2004.
Includes bibliographical references.
(cont.) algorithm, at one extreme, and complete enumeration, at the other extreme. We derive worst-case approximation guarantees on the solution produced by such an algorithm for matroids. We then define a continuous relaxation of the original problem and show that some of the derived bounds apply with respect to the relaxed problem. We also report on a new bound for independence systems. These bounds extend, and in some cases strengthen, previously known results for standard best-in greedy.
This dissertation consists of two parts. In the first part, we address a class of weakly-coupled multi-commodity network design problems characterized by restrictions on path flows and 'soft' demand requirements. In the second part, we address the abstract problem of maximizing non-decreasing submodular functions over independence systems, which arises in a variety of applications such as combinatorial auctions and facility location. Our objective is to develop approximate solution procedures suitable for large-scale instances that provide a continuum of trade-offs between accuracy and tractability. In Part I, we review the application of Dantzig-Wolfe decomposition to mixed-integer programs. We then define a class of multi-commodity network design problems that are weakly-coupled in the flow variables. We show that this problem is NP-complete, and proceed to develop an approximation/reformulation solution approach based on Dantzig-Wolfe decomposition. We apply the ideas developed to the specific problem of airline fleet assignment with the goal of creating models that incorporate more realistic revenue functions. This yields a new formulation of the problem with a provably stronger linear programming relaxation, and we provide some empirical evidence that it performs better than other models proposed in the literature. In Part II, we investigate the performance of a family of greedy-type algorithms to the problem of maximizing submodular functions over independence systems. Building on pioneering work by Conforti, Cornu6jols, Fisher, Jenkyns, Nemhauser, Wolsey and others, we analyze a greedy algorithm that incrementally augments the current solution by adding subsets of arbitrary variable cardinality. This generalizes the standard best-in greedy
by Amr Farahat.
Ph.D.

Doctor of Philosophy
Department of Industrial and Manufacturing Systems Engineering
Todd Easton
Integer Programming (IP) problems are a common type of optimization problem used to solve numerous real world problems. IPs can require exponential computational effort to solve using the branch and bound technique. A popular method to improve solution times is to generate valid inequalities that serve as cutting planes. This dissertation introduces a new category of cutting planes for general IPs called inequality merging. The inequality merging technique combines two or more low dimensional inequalities, yielding valid inequalities of potentially higher dimension. The dissertation describes several theoretical results of merged inequalities. This research applies merging inequalities to a frequently used class of IPs called multiple knapsack (MK) problems. Theoretical results related to merging cover inequalities are presented. These results include: conditions for validity, conditions for facet defining inequalities, merging simultaneously over multiple cover inequalities, sequentially merging several cover inequalities on multiple variables, and algorithms that facilitate the development of merged inequalities. Examples demonstrate each of the theoretical discoveries. A computational study experiments with inequality merging techniques using benchmark MK instances. This computational study provides recommendations for implementing merged inequalities, which results in an average decrease of about 9% in computational time for both small and large MK instances. The research validates the effectiveness of using merged inequalities for MK problems and motivates substantial theoretical and computational extensions as future research.

Class of 2013 Abstract
Specific Aims: The objective of this quality improvement project is to evaluate if drug therapy problems in a community pharmacy setting can be identified via patient counseling at the time of prescription pick up. The central hypothesis of the project is that patient consultation will aid in identifying drug therapy problems and reduce the amount of negative effects posed by these problems. Methods: This project will assess data obtained through a medication therapy intervention report utilized in multiple community pharmacy environments in Arizona. Any consultation provided to a patient by a pharmacist or pharmacy intern regarding a new or transferred prescription will be eligible for data collection. The primary dependent variable is the number of drug therapy problems identified during consultation. Drug therapy problems will be assessed via expert opinion to identify the potential negative impact they may have posed to patients. Data analysis will involve the frequency and type of drug therapy problems identified during data collection. Main Results: A total of 1305 prescriptions were screened during the data collection period. A total of 29 drug therapy problems were identified upon patient consultation. This yielded a 2.2% drug therapy problem occurrence during data collection. The most commonly occurring drug therapy problem involved a patient drug allergy or sensitivity issue. Conclusion: Future research is warranted on the effects that drug therapy problems have on patients and the healthcare system. This project is descriptive in nature and may not be applicable to every community pharmacy in Arizona.

Thesis (MEd)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: In many countries, due to a growing criticism of the inadequacy of mathematics curricula, reforms have been undertaken across the world for meeting new social and technological needs and many researchers have begun to pay attention to the way mathematics is learned and taught. In the same vein, this study aims to investigate innovative and appropriate teaching strategies to introduce in the Rwandan educational system in order to foster students' mathematical thinking and problem solving skills. For this, a classroom-based research experiment was undertaken, focusing on meticulous observation, description and critical analysis of mathematics teaching and learning situations. In the preparation of the research experiment, three mathematics teachers were helped to acquire proficiency in doing mathematics and to refine their teaching strategies, as well as to enable them to create a mathematics classroom culture that fosters students' understanding of mathematics through the problem solving process. Three classes of 121 students of the second year, their ages ranging from 14 years to 16 years, chosen from three different secondary schools in Rwanda, participated in this research experiment. Students were taught an experimental programme based on solving contextualised algebra problems in line with the constructivist approach towards mathematics teaching and learning. Twenty-four mathematics lessons were observed in the three classes and students' learning activities were systematically recorded, focusing on teacher-students and student-student interaction. The participating teachers experienced many difficulties in implementing new teaching strategies based on a problem solving approach but were impressed and encouraged by their students' abilities to generate different and unexpected ways of solving problem situations. However, the construction of mathematical models of non-routine problems constituted the most difficult task for many students because it required a high level of abstraction, characterising algebraic reasoning. Despite evident cognitive obstacles, a substantial improvement in students' systematic reasoning with respect to the different steps in the problem solving process, namely formulating a mathematical model, solving a model, verifying the solution and interpreting the answer, was progressively observed during the experiment. Many students had to overcome a language problem, which inhibited their understanding and interpretation of mathematical problem situations and deeply affected their active participation in classroom discussions. In this study, small group work and group discussions gave rise to excellent and successful teaching and learning situations which were appreciated and continuously improved up by the teachers. They provided students with opportunities for learning to argue about their mathematical thinking and to communicate mathematically. This kind of classroom organisation created an ideal learning environment for students but an uncomfortable teaching situation for teachers. It required much effort from the teachers to transform the mathematics classroom into a forum of discussion in setting up stimulating and challenging tasks for students, in working efficiently with different groups and in moderating the whole class discussion. It was unrealistic to expect spectacular changes in teaching practices established over years to take place during a period of a month. This type of change requires sufficient time and support. However, teachers did develop a new and practical vision of mathematics teaching strategies focusing on students' full engagement in exploring and grappling with problematic situations in order to solve problems. Teachers made remarkable efforts in internalising and adopting their new role of mediators of students' mathematics learning and in being more flexible in their teaching styles. They learned to communicate with their students, to accept students' explanations and suggestions, to encourage their logical disagreement and to consider their errors and misconceptions constructively. Students' results in the pre-test and the post-test showed their low performance in building mathematical models especially when they had to use symbols but revealed a significant progress in the students' ways of thinking which was observed through the variety and originality of their strategies, their systematic work and their perseverance in solving algebra problems. Students also developed positive attitudes to do mathematics; this was exhibited by their pride and satisfaction to accomplish nonroutine tasks by themselves. Teachers' comments indicated that they work under pressure to cover an overloaded mathematics curriculum and have poor support from educational authorities. For them, mathematics IS socially considered as a difficult subject. For many students, mathematics IS a gatekeeper to access higher levels of education; to fail in mathematics unfortunately implies to fail at school and in life. Students' negative attitudes towards mathematics were mainly due to their repeated failures in mathematics, but also to some mathematics teachers who intimidate and discourage their students. Both educational authorities and teachers should make efforts to rethink an appropriate mathematics curriculum and alternative teaching strategies in order to efficiently prepare students to meet new societal and technological requirements.
AFRIKAANSE OPSOMMING: As gevolg van toenemende kritiek oor die kwaliteit van wiskundekurrikula, is bewegings vir hervorming wêreldwyd geïnisieer om nuwe sosiale en tegnologiese behoeftes aan te spreek en baie navorsing is gedoen oor die wyse waarop wiskunde geleer en onderrig word. In lyn hiermee, is die doel van hierdie studie om innoverende en geskikte onderrigstrategieë te ondersoek om in die Rwandese onderwysstelsel in te voer om leerders se wiskundige denke en probleemoplossingsvaardighede te ontwikkel. Om dit te bereik, is 'n klaskamergebaseerde navorsingseksperiment uitgevoer, met die klem op fyn waarneming, beskrywing en kritiese ontleding van wiskunde leer- en onderrigsituasies. As voorbereiding tot die navorsingseksperiment is drie wiskunde-onderwysers gehelp om vaardighede te verwerf in die doen van wiskunde en om hulonderrigstrategieë te verfyn, asook om hulle in staat te stelom 'n wiskunde-klaskamerkultuur te vestig wat leerders se begryping van wiskunde deur die probleemoplossingsproses ontwikkel. Drie klasse van 121 leerders in die tweede jaar, tussen 14 en 16 jaar oud, is uit drie verskillende hoërskole in Rwanda gekies om aan die navorsing deel te neem. Die leerders is deur middel van 'n eksperimentele program onderrig wat gebaseer is op die oplossing van gekontekstualiseerde algebraprobleme in ooreenstemming met 'n konstruktivistiese benadering tot wiskunde-leer en -onderrig. Vier-en-twintig wiskundelesse is in die drie klaskamers waargeneem en leerders se leeraktiwiteite is stelselmatig opgeskryf, met die klem op onderwyser-leerder en leerder-leerder interaksie. Die betrokke onderwysers het baie probleme ondervind om nuwe onderrigstrategieë gebaseer op 'n probleemoplossingsbenadering te implementeer, maar was baie beïndruk en begeesterd deur hulleerders se vermoë om verskillende en onverwagte planne te beraam om probleme op te los. Die opstelling van wiskundige modelle vir nie-roetine probleme was vir baie leerders die moeilikste taak omdat dit 'n hoë vlak van abstraksie wat kenmerkend is van algebraïese denke verteenwoordig. Ten spyte van kognitiewe struikelblokke was daar nogtans 'n merkbare verbetering in leerders se logiese redeneringsprosesse soos geopenbaar in die toepassing van die verskillende stappe van die probleemoplossingsproses, naamlik die formulering van 'n wiskundige model, die oplossing van die model, verifiëring van die oplossing en interpretasie van die antwoord. Baie studente is gekniehalter deur 'n taalprobleem wat hul begrip en interpretasie van wiskundige probleemsituasies en hul vrymoedigheid om aan klaskamergesprekke deel te neem, aan bande gelê het. Inhierdie studie het kleingroepwerk en groepbesprekings suksesvolle onderrig- en leersituasies geskep wat deur die onderwysers raakgesien en verder uitgebou is. Dit het geleenthede geskep vir die leerders om oor hul wiskundige denke te argumenteer en om wiskundig te kommunikeer. Hierdie soort klaskamerorganisasie het 'n ideale leeromgewing vir leerders geskep maar 'n ongemaklike onderrigomgewing vir onderwysers. Dit het baie van onderwysers geverg om die wiskundeklaskamer in 'n gespreksforum te omskep deur stimulerende en uitdagende probleme aan leerders te stel, deur met verskillende groepe te werk en deur die algemene klaskamerbesprekings te fasiliteer. Dit was onrealisties om binne die bestek van 'n maand grootskaalse veranderinge in onderwyspraktyke wat oor 'n tydperk vanjare posgevat het, te verwag. Hierdie soort verandering benodig genoeg tyd en ondersteuning. Onderwysers het nogtans 'n nuwe en praktiese visie ontwikkel van wiskunde-onderrigstrategieë wat fokus op leerders se betrokkenheid by die ondersoek en oplossing van probleme wat vir hulle uitdagend en nie-roetine was. Onderwysers het daadwerklike pogings aangewend om hul nuwe rolle as mediators te internaliseer en te aanvaar, en om meer soepel onderrigstyle te ontwikkel. Hulle het geleer om met hulleerders te kommunikeer, om leerders se verduidelikings en voorstelle te aanvaar, om logiese argumentering aan te moedig en om foute en wankonsepte konstruktief te benader. Leerders se resultate in die voor- en na-toetse dui op swak vermoë om wiskundige modelle te bou veral wanneer hulle simbole moes gebruik, maar wys beduidende vordering in leerders se denke, wat gemanifesteer het in die verskeidenheid en oorspronklikheid van hul strategieë, hul sistematiese werk en hul voortgesette pogings om algebraprobleme op te los. Leerders het ook positiewe instellings teenoor die doen van wiskunde ontwikkel; dit is getoon deur hul trots en tevredenheid wanneer hulle self nie-roetine take opgelos het. Onderwysers se kommentaar openbaar dat hulle onder druk werk om 'n oorlaaide wiskundekurrikulum af te handel en dat hulle min ondersteuning van onderwyshoofde kry. Hulle sê ook dat wiskunde deur die breë gemeenskap as 'n moeilike vak beskou word. Vir baie leerders is wiskunde 'n hekwagter wat toegang tot verdere onderwys en opleiding beheer; om in wiskunde te faal beteken om op skool te faal en om in die lewe te faal. Leerders se negatiewe instellings teenoor wiskunde was hoofsaaklik as gevolg van hul herhaalde mislukkings in skoolwiskunde maar ook as gevolg van sommige wiskunde-onderwysers wat hulleerders intimideer en ontmoedig. Beide onderwyshoofde en onderwysers behoort pogings aan te wend om te besin oor 'n geskikte wiskundekurrikulum en alternatiewe onderrigstrategieë om leerders meer doeltreffend voor te berei om aan nuwe sosiale en tegnologiese eise te voldoen.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.
"February 2, 2004."
Includes bibliographical references (leaf 103).
There exists a large class of problems that incorporate both logical decision and algebraic constraints. For example, in cooperative path planning (CPP) problem, obstacle avoidance can be achieved by selecting a direction in which to avoid every obstacle, which in turn imposes an inequality constraint. Traditionally, these hybrid decision-control problems (HDCPs) are encoded in a binary integer program (BIP). These BIPs are solved using Branch and Bound (B&B) techniques. Two problems arise with this approach. First, binary arithmetic is not a natural representation for expressing complex logical choices. Propositional and higher order logics offer a more natural encoding, and computational methods exploit this encoding. Second, current BIP solution methods are to slow to solve large HDCPs online. To address these problems, this thesis introduces an approach that unifies representations and solution methods for logic and mathematical programming. To address representational adequacy, this thesis introduces the Clausal Linear Program (CLP) formulation, which encodes logical choice using propositional clauses and continuous control decisions using linear inequalities. CLPs offer a more compact and natural encoding than BIPs for many problems of logical choice. To address computational efficiency, this thesis introduces a branch and bound method for solving CLPs, analogous to BIP-B&B. This method is then unified with conflict-directed search and unit propagation. The resulting method, CDCL-B&B, searches in a best first order, while using conflicts to steer the search away from inconsistencies. Randomized experiments on CPP problems were performed using CDCL-B&B and a BIP-B&B algorithm. Results showed that CDCL-B&B improved time efficiency by
by Raj Krishnan.
M.Eng.

The thesis explores the focus of district nursing practice in order to identify areas of study for inclusion in the district nurse curriculum. The "focus" is defined as the point of greatest activity (Chambers, 1991) and so evolves from nursing actions. It is assumed that some nursing actions are dependent upon the patients'needs/problems identified in the assessment process. As all district nurse students are Registered General Nurses they are familiar with nursing needs in hospital and the knowledge that underpins them. The problems experienced frequently by patients at home were explored and compared with those that occur frequently in hospital. The differences in the problems between the two settings enabled knowledge specific to district nursing to be identified. Data was collected from hospitals and the community in one outer London Health Authority. The research was structured through Facet theory which allowed the focus and parameters of the study to be made explicit. The data was analysed using a multiple sorting task, multidimensional scaling procedures and statistical tests. The results demonstrated that a relationship exists between some problems and illustrated those that are likely to occur together. A difference was found between some common problems experienced by patients at home from those experienced in hospital. However, other problems occur with equal frequency and severity in both settings. This suggests that the focus of care is different at home from hospital but that a family resemblance exists. It was argued that the focus of district nursing is on health teaching, which is facilitated by the giving of physical care. Concepts fundamental to district nursing, which underpin the focus of care at home, were identified. Areas of study for inclusion in the district nurse curriculum were suggested and questions for further research raised.