Dissertations / Theses on the topic 'Individual model'

La cirurgia del raquis lumbar ha augmentat substancialment amb el pas dels anys i això ha condicionat la pràctica de força estudis, tant clínics com experimentals, per millorar les tècniques, fer-les més eficients i segures pel pacient. Malgrat tot, aquestes intervencions presenten un índex de fracassos que es situen entre el 5 i el 50%, segons la literatura. Una de les possibles causes de fracàs és la fibrosi postquirúrgica. Sobre la fibrosi s’han fet nombrosos estudis, tant per acceptar que pot ser causa de dolor postoperatori com per rebutjar aquesta teoria. A més a més ha motivat un plegat de treballs que avaluen l’efectivitat i la necessitat de diferents mètodes que pretenen evitar la formació d’adherències entre aquesta formació fibrosa i les estructures neurals. Alhora, força estudis conclouen que el fracàs de la cirurgia lumbar és un problema multifactorial. Característiques individuals o factors operatoris tan mesurables com l’edat, el pes, el sexe, la duració de la cirurgia, el sagnat o la infecció poden interrelacionar-se i empobrir el resultat histològic i/o clínic de la cirurgia. Inspirats en aquesta bibliografia, dissenyàrem un estudi experimental on intervinguérem a 13 ovelles adultes per practicar laminectomies en els espais L3 i L5. Es recolliren els paràmetres quirúrgics, les troballes histològiques i les característiques individuals de cada animal. En primer lloc, compararen entre sí dos dels mètodes barrera més emprats i validats per les publicacions científiques, l’empelt de greix lliure i el gel antiadherent ADCON® - L. En segon lloc, observàrem el procés cicatricial d’una laminectomia lumbar sense implant i, a partir d’aquí, valorarem el possible impacte dels dos implants sobre la histologia del grup control. Tercer, ens plantejàrem si les dades histològiques, individuals i operatòries del nostre estudi es correlacionaven entre elles i, en quart lloc, avaluàrem el maneig dels animals i tot el conjunt del procediment experimental a fi d’explorar la validesa de l’ovella com model experimental en la cirurgia lumbar. Els nostres resultats conclouen que no hi ha diferències significatives en l’ús del greix o del gel antiadherent. La fibrosi postlaminectomia, tot i presentar-se sempre, no ocasiona cap compromís a les estructures neurals. El pes de l’animal pot influir en el resultat de la cirurgia, no en una variable concreta sinó en una conjunt d’elles. Finalment, podem dir que l’ovella pot ser un bon animal d’experimentació en la cirurgia lumbar.
Lumbar spine surgery has increased over the past few years. This has resulted in many experimental and clinical studies aimed to improve the surgical techniques, to make them more efficient and safe. Nevertheless, the index of failure of these procedures ranges from 5 to 50%, being postlaminectomy fibrosis one of the main potential complications. Different studies either support or refuse the idea that postsurgical pain is mainly due to fibrosis. Moreover, many studies have been conducted to explore the need and effectiveness of interventions that could prevent fibrosis and its penetration into the neural canal showing inconclusive results. Some authors believe that lumbar surgery failure has a multifactorial origin. Several studies conclude that individual differences as well as surgical factors like age, weight, gender, duration of surgery, bleeding or infection might be interrelated and could be responsible for negative clinical and histologic results. We designed an experimental animal study where a lumbar laminectomy at L3 and L5 was practiced to 13 sheep. Surgical parameters, histological findings and individual physical data were collected for each animal. First, we wanted to know if two of the most common materials used as barrier methods for fibrosis, a free fat graft and the antiadhesion gel ADCON® - L, would result in different outcomes. Second, we wanted to explore differences in the healing process and the histology between the aforementioned methods and controls where no barrier methods were applied. Third, we wanted to know if histological, individual and surgical variables in our study correlated to each other. Fourth, we explored the scientific validity and the practicality of the sheep as an experimental model in lumbar laminectomy. Our results concluded that there are no significant differences between the free fat graft and the antiadhesion barrier gel. Postlaminectomy fibrosis was present in all cases and did not cause any significant adherence in the neural canal. The multivariate statistical analysis suggests that body weight might influence different parameters related to surgical outcome. From a practical point of view, our study indicates that the domestic sheep could be a good animal model for lumbar laminectomy in human beings.

Each individual has a distinguished writing style. But natural language generation systems pro- duce text with much less variety. Is it possible to produce more human-like text from natural language generation systems by mimicking the style of particular authors? We start by analysing the text of real authors. We collect a corpus of texts from a single genre (food recipes) with each text identified with its author, and summarise a variety of writing features in these texts. Each author's writing style is the combination of a set of features. Analysis of the writing features shows that not only does each individual author write differently but the differences are consistent over the whole of their corpus. Hence we conclude that authors do keep consistent style consisting of a variety of different features. When we discuss notions such as the style and meaning of texts, we are referring to the reac- tion that readers have to them. It is important, therefore, in the field of computational linguistics to experiment by showing texts to people and assessing their interpretation of the texts. In our research we move the thesis from simple discussion and statistical analysis of the properties of text and NLG systems, to perform experiments to verify the actual impact that lexical preference has on real readers. Through experiments that require participants to follow a recipe and prepare food, we conclude that it is possible to alter the lexicon of a recipe without altering the actions performed by the cook, hence that word choice is an aspect of style rather than semantics; and also that word choice is one of the writing features employed by readers in identifying the author of a text. Among all writing features, individual lexical preference is very important both for analysing and generating texts. So we choose individual lexical choice as our principal topic of research. Using a modified version of distributional similarity CDS) helps us to choose words used by in- dividual authors without the limitation of many other solutions such as a pre-built thesauri. We present an algorithm for analysis and rewriting, and assess the results. Based on the results we propose some further improvements.

In this thesis, we investigate the estimation problem of treatment effect from Bayesian perspective through which one can first obtain the posterior distribution of unobserved potential outcome from observed data, and then obtain the posterior distribution of treatment effect. We mainly consider how to represent a joint distribution of two potential outcomes - one from treated group and another from control group, which can give us an indirect impression of correlation, since the estimation of treatment effect depends on correlation between two potential outcomes. The first part of this thesis illustrates the effectiveness of adapting Gaussian mixture models in solving the treatment effect problem. We apply the mixture models - Gaussian Mixture Regression (GMR) and Gaussian Mixture Linear Regression (GMLR)- as a potentially simple and powerful tool to investigate the joint distribution of two potential outcomes. For GMR, we consider a joint distribution of the covariate and two potential outcomes. For GMLR, we consider a joint distribution of two potential outcomes, which linearly depend on covariate. Through developing an EM algorithm for GMLR, we find that GMR and GMLR are effective in estimating means and variances, but they are not effective in capturing correlation between two potential outcomes. In the second part of this thesis, GMLR is modified to capture unobserved covariance structure (correlation between outcomes) that can be explained by latent variables introduced through making an important model assumption. We propose a much more efficient Pre-Post EM Algorithm to implement our proposed GMLR model with unobserved covariance structure in practice. Simulation studies show that Pre-Post EM Algorithm performs well not only in estimating means and variances, but also in estimating covariance.

This study aimed to confirm that social participation may influence empowerment as one ofthe four components explained by the theory. The hypothesis proposes systemic interaction of two components of empowerment: intrapersonal and behavioral. 113 urban residents participated in the study. The hypotheses were tested through the use of structural modeling. An intrapersonal component of empowerment, composed of positive empowerment, negative empowerment and socio-political control was identified. This component was affected by the behavioral component that involves social organization, community action and decision making. The hypothesis is accepted and the study provides empirical support to the theory.
Se busca confirmar que la participación social puede influir en el empoderamiento comouno de sus cuatro componentes. La hipótesis propone la interacción sistémica de dos componentes del empoderamiento: intrapersonal y comportamental. Los participantes fueron 113 habitantes urbanos a quienes se les aplicó una encuesta. Los resultados evidencian que el modelamiento estructural identificó un componente intrapersonal del empoderamiento integrado por empoderamiento positivo, empoderamiento negativo y control sociopolítico. Este componente se muestra afectado por el componente de comportamiento conformado por la organización social, las acciones comunitarias y la toma de decisiones. Se acepta la hipótesis y se proporciona sustento empírico a la teoría.

Students’ metacognition, that is, the ability to accurately assess one’s skill level and to update one’s internal model of those skills, is a crucial educational factor, as it can help students selfregulate their learning. The purpose of this thesis is to assess how individuals’ metacognitive abilities relate to learning processes and outcomes in STEM-related tasks. It also highlights how they relate to students’ characteristics, as their gender. This thesis also presents the first steps towards a methodology to teach programming and robotics to elementary-school children and a study on digital technologies in museums to present historical content. Finally, it also explores prediction and collaborative behaviour in young adults in the autistic spectrum, and how this behaviour is self-perceived during a collaborative task with an artificial agent.
Las capacidades metacognitivas de los/as estudiantes (la habilidad de evaluar con precisión las capacidades de uno/a mismo/a y de actuar con nuestro modelo interno de estas capacidades) es un factor educativo crucial, ya que puede ayudar a los/as estudiantes a autorregular su proceso de aprendizaje. El objetivo de esta tesis es evaluar como las habilidades metacognitivas de los/as estudiantes se relacionan con su proceso de aprendizaje y resultados en tareas STEM (Ciencia, tecnología, ingeniería y matemáticas). También investiga cómo se relacionan estas capacidades con sus características, como el género. Esta tesis también presenta los primeros pasos para desarrollar una metodología para enseñar programación y robótica a niños/as de primaria y un estudio sobre tecnologías digitales en museos para mostrar contenido histórico. Finalmente, explora también procesos de predicción y colaboración en adultos jóvenes dentro del espectro autista y cómo perciben su comportamiento durante una actividad colaborativa con un agente sintético.
Les capacitats metacognitives dels/les estudiants (l’habilitat d’avaluar amb precisió els capacitats d’un mateix i d’actualitzar el nostre model intern d’aquestes capacitats) és un factor educatiu crucial, ja que pot ajudar els/les estudiants a autoregular el seu procés d’aprenentatge. L’objectiu d’aquesta tesi és avaluar com les habilitats metacognitives dels/les estudiants es relacionen amb el seu procés d’aprenentatge i resultat en tasques STEM (ciència, tecnologia, enginyeria i matemàtiques). També investiga com es relacionen amb les seves característiques, com el gènere. Aquesta tesi també presenta els primers passos per desenvolupar una metodologia per ensenyar programació i robòtica a nens/es de primària i un estudi sobre tecnologies digitals en museus per mostrar contingut històric. Finalment, també explora processos de predicció i col·laboració en adults joves dintre de l’espectre autista i com perceben seu comportament durant una activitat col·laborativa amb un agent sintètic.

Master of Science
Department of Electrical and Computer Engineering
Caterina Maria Scoglio
Japanese Encephalitis (JE) is a vector-borne disease transmitted by mosquitoes and maintained in birds and pigs. An interconnected network model is proposed to examine the possible epidemiology of JE in the USA. Proposed JE model is an individual-level network model that explicitly considers the feral pig population and implicitly considers mosquitoes and birds in specific areas of Florida, North Carolina, and South Carolina. The virus transmission among feral pigs within a small geographic area (<60 sq mi areas) are modeled using two network topologies— fully connected and Erdos-Renyi networks. Connections between locations situated in different states (interstate links) are created with limited probability and based on fall and spring bird migration patterns. Simulation results obtained from the network models support the use of the Erdos-Renyi network because maximum incidence occurs during the fall migration period which is similar to the peak incidence of the closely related West Nile virus (WNV), another virus in the Japanese Encephalitis group (Flaviviridae) that is transmitted by both birds and mosquitoes. Simulation analysis suggested two important mitigation strategies: for low mosquito vectorial capacity, insecticidal spraying of infected areas reduces transmission and limits the outbreak to a single geographic area. Alternatively, in high mosquito vectorial capacity areas, birds rather than mosquitoes need to be removed/controlled.

It is crucial to study the denitrification process driven by bacteria as it is one of the most important environmental processes for several reasons: i) it has an application in the removal of nitrogen (N) from high-N waste materials ii), it is one of the mechanisms to N-fertilizer¿s loss, iii) it contributes to the emissions of gasses with large global warming potential, and iv) it is the mechanism by which the global nitrogen cycle is balanced. Many models have been developed in the framework of continuous models to deal with the complexity of the denitrification process in order to become predictive models, but some of the assumptions contained in them are not realistic enough in those contexts, and also they have their own constraints and limitations. On the other hand, the researchers have paid more attention to the role of microbial activity with the advance of experimental techniques. Discrete models, such as individual-based models (IBMs), can be developed and applied to microbial systems due to the fact that they allow representation of some intracellular characteristics regarding the complexity of the micro-organisms, which constitutes a key advantage of this modelling approach in the study of the different biotechnological processes. The IBM is able to incorporate and accommodate the behaviour of denitrifying bacteria, and investigate their metabolism from different and attractive perspectives. A key factor in modelling the microbial activity is the methodology followed to represent metabolic pathways. A cellular metabolic model could be based on a non-equilibrium thermodynamic approach such as the Thermodynamic Electron Equivalents Model (TEEM), which is developed for biomass yield prediction using the associated standard Gibbs free energies and the bioenergetics growth efficiency between cell anabolism and catabolism. The main objective of this doctoral thesis is to develop an IBM to study denitrification processes driven by denitrifying bacteria, using TEEM to write microbial metabolic reactions (MMRs) which represent the metabolic pathways as the center of the individual sub-model. Two new computational models of the INDISIM family, INDISIM-Paracoccus and INDISIM-Denitrification have been designed, implemented on the NetLogo platform, parameterized and calibrated with experimental data to analyze the system dynamics in a bioreactor in batch and continuous culture with denitrifying bacteria growing in it. The bioreactor conditions can be aerobic and/or anaerobic, and the growing media is liquid medium with an electron donor, C-source, N-source, and oxygen and all N-oxides as electron acceptors. An open access and open source tool has been developed to write MMRs based on TEEM. It is called MbT-tool which stands for Metabolism-based on Thermodynamics. Using MbT-Tool three sets of MMRs have been written, which are the centre of the individual sub-model for INDISIM-Paracoccus and INDISIM-denitrification, representing reactions involved in: i) cellular maintenance, ii) individual mass synthesis, and iii) individual mass degradation to reduce cytotoxic products. The simulation results obtained with INDISIM-Paracoccus and INDISIM-Denitrification have been compared with experimental data published by Felgate et al. (2012) regarding the growth of Paracoccus denitrificans and Achromobacter xylosoxidans in a bioreactor. According to the statistical analysis of the simulations results, for both denitrifying bacteria tested, the IBMs developed show better adjustments in the assays with electron donor limited than in the assays with electron acceptor limited.
L’estudi del procés de desnitrificació és rellevant, ja que és un important procés mediambiental, a causa que: i) és un dels mecanismes que ocasiona una pèrdua dels fertilitzants de nitrogen (N), ii) és d’utilitat en l’eliminació de N en residus amb un alt contingut en N, iii) contribueix en les emissions de gasos d’alt potencial sobre l’escalfament global, i iv) és el mecanisme pel qual es tanca el cicle del N. S’han desenvolupat diversos models continus per tractar la complexitat del procés de desnitrificació en sistemes ambientals per tal de que puguin ser models amb capacitat predictiva, però alguns dels supòsits que es fan no són prou realistes i tenen les seves mancances i limitacions. D’altra banda, els investigadors estan posant més atenció en el rol que juga l’activitat microbiana, des de que en els darrers anys s’ha desenvolupat i avançat en tècniques experimentals de manera important. Models discrets, com els models basats en l’individu (IBMs), poden ser desenvolupats i utilitzats en sistemes microbians ja que permeten la representació d’algunes característiques intracel·lulars atenent a la complexitat dels microorganismes, cosa que resulta clau a l’hora d’abordar aquest nou enfoc per l’estudi de diversos processos biotecnològics. Els IBMs són capaços d’incorporar el comportament de les bactèries desnitrificants i d’investigar el seu metabolisme des de perspectives diferents. Un factor clau en la modelització de l’activitat microbiana és la metodologia seguida per a representar les rutes metabòliques. Un model de metabolisme cel·lular podria estar basat en l’enfoc de la termodinàmica de no-equilibri, com per exemple el denominat Model Termodinàmic d’Electrons Equivalents (TEEM). TEEM va ser desenvolupat per predir el rendiment de la biomassa utilitzant les energies lliures estàndards de Gibbs associades i l’eficiència bioenergètica de creixement entre els processos anabòlics i catabòlics de la cèl·lula. L’objectiu principal d’aquesta tesis doctoral és desenvolupar un IBM per l’estudi dels processos de desnitrificació duts a terme per bactèries desnitrificants, mitjançant l’ús del TEEM per descriure les reaccions metabòliques microbianes (MMRs) que representen les vies metabòliques i són el centre del sub-model individual. Dos nous models computacionals de la família d’INDISIM, l’INDISIM-Paracoccus i l’INDISIM-Denitrification han estat dissenyats, implementats en la plataforma de NetLogo, i parametritzats i calibrats amb dades experimentals per analitzar la dinàmica d’un sistema format per bactèries desnitrificants en un bioreactor en un cultiu tancat i/o continu, en condicions aeròbies i/o anaeròbies. El medi de cultiu és líquid i conté un donador d’electrons, oxigen i òxids de N com acceptors d’electrons, una font de carboni i una de N. S’ha creat una eina d’accés i codi obert per escriure les MMRs basades en el TEEM i és anomenada MbT-tool (Metabolisme basat en la Termodinàmica). Utilitzant MbT-tool es poden descriure tres grups de MMRs, que seran el centre del sub-model individual per l’INDISIM-Paracoccus i l’INDISIM-denitrification, i que són reaccions involucrades en: i) el manteniment cel·lular, ii) la síntesi individual de massa, i iii) la degradació individual de massa per reduir els productes citotòxics. Els resultats de simulació obtinguts amb INDISIM-Paracoccus i INDISIM-Denitrification han estat comparats amb les dades experimentals publicades per Felgate et al. (2012), sobre el creixement de Paracoccus denitrificans i Achromobacter xylosoxidans en un bioreactor. Segons l’anàlisi estadístic dels resultats, per les dues bactèries desnitrificants amb les quals s’ha testat, els IBMs desenvolupats mostren millors ajustos en els assajos amb donadors d’electrons limitants que en els assajos amb acceptors d’electrons limitants. El desenvolupament d’un IBM i la seva aplicació amb cert nivell de detall i complexitat intracel·lular constitueix una avantatge per la investigació de la desnitrificació bacterià.
Es relevante estudiar la desnitrificación ya que es un importante proceso medioambiental, debido a que: i) es uno de los mecanismos que explica la pérdida de fertilizantes de nitrógeno (N), ii) tiene aplicación en la remoción de N proveniente de residuos con alto contenido de N, iii) contribuye a las emisiones de gases que presentan gran potencial de calentamiento global, y iv) es el mecanismo por el cual se balancea el ciclo del N. Varios modelos han sido desarrollados usando el enfoque de la modelización continua para hacer frente a la complejidad del proceso de la desnitrificación, con la finalidad de obtener modelos predictivos, pero algunas de sus suposiciones no son suficientemente reales en este contexto, además estos modelos tienen sus propias restricciones y limitaciones. Por otro lado, los investigadores están prestando más atención al rol de la actividad microbiana, desde que en los últimos años se han desarrollado y avanzado las técnicas experimentales de manera importante. Modelos discretos, como los modelos-basados en el individuo (IBMs), pueden ser desarrollados y aplicados a sistemas microbianos ya que permiten representar algunas de las características intracelulares relacionadas con la complejidad de los microorganismos, lo cual constituye una ventaja clave de este enfoque de modelización en el estudio de diversos procesos biotecnológicos. El IBM es capaz de incorporar y adaptar el comportamiento de las bacterias desnitrificantes e investigar su metabolismo desde perspectivas distintas. Un factor clave para modelizar la actividad microbiana es la metodología utilizada para representar las rutas metabólicas. Un modelo metabólico celular puede estar basado en la termodinámica del no equilibrio como el Modelo Termodinámico de Electrones Equivalentes (TEEM), el cual está desarrollado para la predicción del rendimiento de la biomasa usando las energías estándar de Gibbs junto con la eficiencia bioenergética de crecimiento entre anabolismo y catabolismo celular. El objetivo principal de esta tesis doctoral es desarrollar un IBM para estudiar la desnitrificación bacteriana, usando el TEEM para escribir reacciones metabólicas microbianas (MMRs) las cuales representan a las rutas metabólicas y son el centro del sub-modelo individual. Dos nuevos modelos computacionales de la familia INDISIM, el INDISIM-Paracoccus y el INDISIM-Denitrification, han sido diseñados, implementados en la plataforma NetLogo, parametrizados y calibrados con datos experimentales para estudiar la dinámica del crecimiento de las bacterias desnitrificantes dentro de un bioreactor en cultivos cerrados y continuos, en condiciones aerobias o anaerobias. El medio de cultivo es líquido y contiene un donador de electrones, oxígeno y los óxidos de N como aceptores de electrones, una fuente de carbono y una fuente de N. Una herramienta de acceso libre y código abierto ha sido desarrollada para escribir las MMRs basadas en TEEM y es llamada MbT-Tool (Metabolismo basado en la Termodinámica). Utilizando MbT-Tool se pueden escribir tres grupos de MMRs que han sido el centro del sub-modelo individual para INDISIM-Paracoccus e INDISIM-Denitification, y que representan las reacciones involucradas en: i) el mantenimiento celular, ii) la síntesis de masa individual, y iii) la degradación de la masa individual para reducir productos citotóxicos. Los resultados de simulación obtenidos con INDISIM-Paracoccus e INDISIMDenitrification han sido comparados los datos experimentales publicados por Felgate et al. (2012) relacionados con el crecimiento de Paracoccus denitrificans y Achromobacter xylosoxidans dentro de un bioreactor. De acuerdo con el análisis estadístico de los resultados de simulación, los IBMs desarrollados muestran mejores ajustes para los experimentos con donador de electrones limitado que para los ensayos con aceptor de electrones limitado. El desarrollo y aplicación de IBMs con algunos detalles y complejidad intracelular, constituyen una ventaja clave en la investigación y comprensión de los diferentes pasos de la desnitrificación bacteriana.

A teoria de redes complexas se consolidou nos últimos anos, graças ao seu potencial como ferramenta versátil no estudo de diversos sistemas discretos. É possível enumerar aplicações em áreas tão distintas como engenharia, sociologia, computação, linguística e biologia. Tem merecido atenção, por exemplo, o estudo da organização estrutural do cérebro, tanto em nível microscópico (em nível de neurônios) como regional (regiões corticais). Acredita-se que tal organização visa otimizar a dinâmica, favorecendo processos como sincronização e processamento paralelo. Estrutura e funcionamento, portanto, estão relacionados. Tal relação é abordada pela teoria de redes complexas nos mais diversos sistemas, sendo possivelmente seu principal objeto de estudo. Neste trabalho exploramos as relações entre aspectos estruturais de redes neuronais e corticais e a atividade nas mesmas. Especificamente, estudamos como a interconectividade entre o córtex e o tálamo pode interferir em estados de ativação do último, considerando-se o sistema tálamo-cortical do gato bem como alguns modelos para geração de rede encontrados na literatura. Também abordamos a relação entre a morfologia individual de neurônios e a conectividade em redes neuronais, e consequentemente o impacto da forma neuronal em dinâmicas atuando sobre tais redes e a eficiência das mesmas no transporte de informação. Como tal eficiência pode ter como consequência a facilitação de processos maléficos às redes, como por exemplo, ataques causados por vírus neurotrópicos, também exploramos possíveis correlações entre características individuais dos elementos que formam as redes complexas e danos causados por processos infecciosos iniciados nos mesmos.
Complex network theory has been consolidated along the last years, owing to its potential as a versatile framework for the study of diverse discrete systems. It is possible to enumerate applications in fields as distinct as Engineering, Sociology, Computing, Linguistics and Biology, to name a few. For instance, the study of the structural organization of the brain at the microscopic level (neurons), as well as at regional level (cortical areas), has deserved attention. It is believed that such organization aims at optimizing the dynamics, supporting processes like synchronization and parallel processing. Structure and functioning are thus interrelated. Such relation has been addressed by complex network theory in diverse systems, possibly being its main subject. In this thesis we explore the relations between structural aspects and the activity in cortical and neuronal networks. Specifically, we study how the interconnectivity between the cortex and thalamus can interfere in activation states of the latter, taking into consideration the thalamocortical system of the cat, along with networks generated through models found in literature. We also address the relation between the individual morphology of the neurons and the connectivity in neuronal networks, and consequently the effect of the neuronal shape on dynamic processes actuating over such networks and on their efficiency on information transport. As such efficiency can consequently facilitate prejudicial processes on the networks, e.g. attacks promoted by neurotropic viruses, we also explore possible correlations between individual characteristics of the elements forming such systems and the damage caused by infectious processes started at these elements.

Saccharomyces cerevisiae is one of the yeasts with major economic, social, and health significance in human culture. Depending on the growth conditions experienced by the cell, S. cerevisiae growth can proceed via fermentative, respirative, or respirofermentative metabolism. Scar formation, unequal division, a limited replicative lifespan, and increase in cell size commensurate with the cell's replicative age are individual characteristics of this yeast affecting the performance of bioprocesses. These characteristics increase the complexity of predictive models and introducing them with ease into a continuous model is not realistic. Nevertheless, an individual-based model is able to accommodate this complexity in a single computational model. Once an individual model is implemented, it has to be parameterized, calibrated, and its adequacy assessed. All these processes ideally require a high number of both individual and system-level experimental observations. The aim of the present thesis is to advance the development of an individual-based methodology to tackle the study of microbial systems driven by the relevant yeast S. cerevisiae. The adequacy of INDISIM-YEAST, an existing individual-based model of a generic budding yeast, is first assessed. In order to obtain valuable individual-based observations to support the desired individual-based methodology, the diversity of S. cerevisiae in experimental individually-oriented observations under different growth conditions and at different stages of the growth curve is verified and assessed. A quantitative individual-based model focusing on the fermentative (anaerobic) growth of the yeast S. cerevisiae has been designed, implemented in Fortran 90, and termed INDISIM-Saccha. The developed model is parameterized, calibrated, its adequacy evaluated, and used to assess in silico ethanol production by means of virtual experiments. The calibration procedure, and the performance and analysis of the data from the virtual experiments is undertaken using the statistical programming language R. The model adequacy is assessed by testing several model predictions both at a system level (glucose depletion, population growth curves) and single-cell level (fraction of budded cells, genealogical age distribution, and cell diameter distribution evolutions). Individual cell diameter observations obtained within the present thesis play a significant role in this assessment. Results of the virtual experiments suggest that differences in cell size distribution can drastically affect the performance and productivity of fermentations, and encourage routine characterization of the inocula in the biotechnological industry. INDISIM-Saccha is also adapted to take into account the aerobic growth of S. cerevisiae and contrasted with two experimental trials with different oxygen levels in the medium. The preliminary simulated results achieved with the model suggest that the approach also has the potential for reproducing aerobic batch cultures of S. cerevisiae. This represents a further step in obtaining a microbial individual-based model to account for the whole set of metabolic alternatives experienced by S. cerevisiae. In order to communicate efficiently, increase accessibility, and favour usability of the INDISIM-Saccha methodology developed, the present thesis also designs and implements INDISIM-YEAST-NL in the freely available programming environment NetLogo. The implementation of this streamlined model in NetLogo lays the foundations for a deeper understanding of the developed methodology and microbial individual-based models in general, and will facilitate future interactions with potential users of INDISIM-Saccha.
El Saccharomyces cerevisiae és un dels llevats que gaudeix de més significació econòmica, social i per a la salut humana. Depenent de les condicions experimentades, el llevat S. cerevisiae pot créixer mitjançant un metabolisme fermentatiu, respiratori o respirofermentatiu. La formació de cicatrius, una divisió desigual, una vida replicativa limitada i un increment de la mida de la cèl.lula amb l’edat replicativa són característiques individuals d’aquest llevat que afecten el comportament dels bioprocessos. Aquestes característiques incrementen la complexitat dels models predictius i dificulten, per tant, la seva inclusió en un model continu de manera realista. No obstant això, un model basat en l’individu sí que és capaç d’acomodar tota aquesta complexitat en un únic model computacional. Una vegada implementat, un model basat en l’individu ha de ser parametritzat, calibrat i la seva adequació ha de ser avaluada. Tots aquests processos requereixen idealment un gran nombre d’observacions experimentals, tant individuals com a nivell del sistema estudiat. L’objectiu general de la tesi present és avançar en el desenvolupament d’una metodologia basada en l’individu per estudiar sistemes microbians conduïts pel llevat S. cerevisiae. Primerament s’avalua l’adequació de INDISIM-YEAST, un model basat en l’individu, ja existent, focalitzat en un llevat genèric. Es verifica i s’avalua la diversitat del S. cerevisiae en observacions experimentals orientades a l’individu en diferents condicions de creixement i en diversos estadis de la corba de creixement de la població. Això permet obtenir observacions basades en l’individu molt valuoses a l’hora de donar suport a la metodologia desitjada. Es desenvolupa i s’implementa en Fortran 90 INDISIM-Saccha, un model quantitatiu basat en l’individu i focalitzat en el creixement fermentatiu (anaerobi) del S. cerevisiae. El model desenvolupat és parametritzat, calibrat, la seva adequació és avaluada i és utilitzat per estudiar in silico la producció d’etanol mitjançant experiments virtuals. El procés de calibratge, l’obtenció i l’anàlisi de les dades dels experiments virtuals s’han realitzat utilitzant el programari estadístic R. L’adequació del model s’avalua testejant diferents prediccions del model a nivell de sistema (corbes de disminució de la glucosa i de creixement de la població) i a nivell de la cèllula individual (evolucions temporals de la fracció de cèl.lules gemades, de la distribució d’edats genealògiques i de la distribució dels diàmetres cel.lulars). Les observacions del diàmetre de les cèl.lules individuals obtingudes a la tesi present juguen un paper significatiu en aquesta avaluació. Els resultats dels experiments virtuals suggereixen que les diferències en la distribució de mides cel.lulars poden afectar dràsticament l’evolució i la productivitat de les fermentacions i suggereixen una caracterització rutinària de l’inòcul a la indústria biotecnològica. L’INDISIM-Saccha també és adaptat per tenir en compte el creixement aeròbic del S. cerevisiae i és contrastat mitjançant dos assajos experimentals amb dos nivells d’oxigen al medi. Els resultats preliminars de la simulació denoten que aquesta aproximació també té el potencial de reproduir cultius discontinus aerobis del S. cerevisiae. Això representa un pas endavant cap a l’obtenció d’un model basat en l’individu que tingui en compte tot el conjunt d’alternatives metabòliques experimentades pel S. cerevisiae. Finalment, aquesta tesi també dissenya i implementa INDISIM-YEAST-NL en l’ambient de programació lliure anomenat NetLogo per tal de comunicar de manera eficient, d’incrementar l’accessibilitat i d’afavorir l’ús de la metodologia INDISIM-Saccha. La implementació d’aquest model simplificat amb NetLogo posa les bases per a una comprensió més alta de la metodologia desenvolupada, i dels models microbians basats en l’individu en general, i facilitarà futures interaccions amb usuaris potencials de l’INDISIM-Saccha.

The title of the research is Sustainability Performance Evaluation Management Systems Model for Individual Organizations and Supply Chains. This research has achieved its aim to develop and demonstrate the practical implementation of a simple and objective sustainability performance evaluation management system model for individual organizations and supply chains. It has resulted in the recognition that a new concept – Network of Interested Partners – underpins the achievement of sustainability. The term acknowledges the interdependence and reflects the essential cooperation that must be achieved between business organisations, their commercially related entities and the local community if progress towards sustainability is to be achieved. It therefore encompasses and extends the concept of a supply chain as currently used. Sustainable Development is defined by the World Commission on Environment and Development as development, which meets the needs of the present without compromising the ability of future societies to meet their own needs. Organizations, as part of human activities, also have to be sustainable. The sustainability of organizations is directly linked to the continual improvement of business performance. Many organizations have found a way to improve performance through the establishment of management systems. International Organization for Standardization (ISO) standards are recognized worldwide as reliable and efficient tools for the implementation of management systems. However, they do not always result in the desired improvement in outcomes. Therefore, if the required improvement of business performance is to be achieved, improved methodologies for development and implementation of performance evaluation (PE) processes are necessary. These methodologies must take into consideration sustainability principles. They also have to be applicable to individual entities and supply chains, with or without management systems in place. Supply chains are important because it is being increasingly recognized that overall supply chain performance is a means of adding value and competitive advantage to all businesses. In the first part of the research a performance evaluation model or PE (version 1 model) was developed. This was used as criteria to compare and evaluate existing performance evaluation processes and outcomes of individual organisations and their respective supply chain within the Gladstone region, Australia. Questionnaires have also been used to identify and evaluate the needs of the interested parties in relation to the organizations’ and supply chains’ business performance and processes of performance evaluation. All the information provided in the first part of the research was used by the researcher to develop the Sustainability Performance Evaluation Management Systems model or SPEMS (version 2 model). This incorporates the concepts of Network of Interested Parties/Partners. In particular, one of the outcomes is recognition that organizations need to establish partnerships if effective supply chain performance improvement is to be achieved. Therefore the establishment of partnerships has become a key requirement for the implementation of SPEMS. The establishment of partnership among participants of a supply chain of Gladstone and implementation of the eight first steps of the SPEMS (version 2 model) in this supply chain was commenced successfully through workshops. The supply chain was formed by commercial organizations, government entities and interested parties from the community. SPEMS requires that partners all have the same level of ownership and authority in the decisions of the supply chain. Some new terms and their definitions have been created within the research to support the new SPEMS model. They include: Network of Interested Partners, sustainability for organizations, sustainability KPI and sustainability friendly organizations. All of the above are encompassed within the final SPEMS (version 3 model).

Thesis (M.A.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on January 3, 2008) Includes bibliographical references.

Evolutionary psychology is a theoretical perspective that is increasingly supported by empirical studies, but its potential to be applied to personality psychology remains largely unfulfilled (Buss, 1999). The current dissertation sought to bring the perspective of evolutionary psychology to bear on personality psychology. Zuroff and colleagues (2010) proposed that an evolutionary theory of personality could seek to identify individual differences in the core social domains that are postulated by evolutionary psychologists. Following this line of thinking, the Social Exchange Styles Questionnaire (SESQ) was developed to assess individual differences within the reciprocity domain (Leybman et al., 2011a). For this dissertation, the social exchange style model was further developed and explored. Article 1 presented an expanded social exchange style model, along with the revised Social Exchange Styles Questionnaire (SESQ-II), which assesses individual differences in ways that people approach and maintain exchange relationships in terms of five dimensions: Tracking, Fairness, Individualism, Benefit-Seeking, and Overinvestment. The SESQ-II showed good internal consistency, retest reliability, and construct validity. Regarding construct validity, multiple regressions demonstrated that none of the social exchange style dimensions was redundant with the Personal Norms of Reciprocity Scale (Perugini et al., 2003), nor with dimensions of adult attachment styles. Additionally, multiple regressions demonstrated that the social exchange style dimensions had predictable relationships with the five-factor traits, and with variables related to perceptions of oneself and others. Article 1 also addressed the relationship between social exchange style dimensions and perceived and received social support in a second study that used a daily diary method. Multilevel modeling showed that Tracking and Overinvestment each negatively predicted perceived support, while Fairness positively predicted perceived support. Additionally, Individualism negatively predicted received support. Social exchange style dimensions predicted social support over and above the five-factor traits.Article 2 sought to extend the social exchange style model and did this by focusing on a single social exchange dimension: Tracking. The developmental antecedents and affective consequences of Tracking were explored. Biological market theory (Noë & Hammerstein, 1994; 1995) was used to identify potential developmental antecedents to Tracking. Multiple regression analyses showed that Tracking was predicted by recalled experiences of having less access to resources than one's peers, having low control over resources, and parental overprotectiveness. Tracking was also predicted by an interaction of low parental warmth and being spoiled. To test the affective consequences of Tracking, we examined the relationship between people's Tracking levels and their emotional reactions to received social support. Using the same sample that was used in the second study of Article 1, multilevel analyses showed that people who were high in Tracking experienced more Joviality on days when they experienced particularly high levels of received support, and that they experienced high Hostility on days when they experienced less received support than usual. Similar results were not obtained with Serenity, Fear, or Guilt as the dependent variables, demonstrating the specificity of the effects to Joviality and Hostility.The results of these studies are discussed in terms of theoretical contributions that stem from integrating evolutionary psychology with personality psychology. Additionally, avenues for future research to elaborate both the content and process components of our model of social exchange styles are identified. Finally, practical applications of social exchange styles are discussed with a focus on implications for conceptualization and treatment of disorders within clinical psychology.
La psychologie évolutionniste est une perspective théorique de plus en plus consolidée par des études empiriques, mais son application potentielle à la psychologie de la personnalité demeure inassouvie (Buss, 1999). La présente thèse se veut une conciliation de la psychologie évolutionniste et la psychologie de la personnalité. Zuroff et ses collègues (2010) suggèrent qu'une théorie évolutionnaire de la personnalité pourrait permettre l'identification de différences individuelles existant dans les domaines sociaux fondamentaux postulé par la psychologie évolutionniste. Le questionnaire des styles d'échanges sociaux (Social Exchange Styles Questionnaire) fut développé dans le but d'évaluer les différences individuels dans le domaine de la réciprocité (Leybman et al., 2011a). Dans cette thèse, le modèle de style d'échange social fut développé et exploré en plus de détails. L'article 1 a présenté un modèle plus détaillé des styles d'échanges sociaux, ainsi que la version révisée du questionnaire des styles d'échanges sociaux (SESQ-II), lequel évalue les différences individuels selon 5 dimensions: Poursuite, Justice, Individualisme, Recherche de Bénéfices et Surinvestissement. Le SESQ-II a démontré une bonne cohérence interne et validité du construit. Aucune des dimensions n'étaient redondantes avec l'échelle de réciprocité de normes personnelles, ni avec les dimensions de styles d'attaches adultes. De plus, les dimensions avaient de relations prévisibles avec les cinq facteurs de trait, et avec des variables liées aux perceptions de soi et d'autrui. L'Article 1 adresse aussi le lien entre les dimensions et le support sociale reçu et perçue. La Poursuite et le Surinvestissement prédissent de façon négative la perception de support, tandis que la Justice prédit positivement la perception de support. De plus, l'Individualisme prédit négativement la réception de support. Nos dimensions prédissent le support social au-delà des cinq facteurs de trait.L'article 2 tentait d'enrichir le model d'échange social en en étudiant une seule dimension d'échange: la Poursuite. Les antécédents développementaux et conséquences affectives de la Poursuites ont été explorés. La théorie du Marcher Biologique (Noe & Hammerstein, 1994; 1995) a été utilisé pour identifier de potentiels antécédents développementaux de la Poursuite. La Poursuite pouvais être prédite par les mémoires d'instances d'avoir eu moins de ressources que ses pairs, d'avoir eu peu de control de ressources, ainsi que de surprotection parentale. La poursuite a aussi été prédite par une interaction entre peu de chaleur parentale et être gâté. Afin de tester les conséquences affectives de la Poursuite, nous avons examiné la relation entre le niveau de Poursuite des gens et leurs réactions émotionnelles face au support sociale reçu. En utilisant la même sous-population qui a été utilisé ultérieurement durant la deuxième étude de l'Article 1, des analyses a multiniveaux ont démontré que les gens qui avaient de haut niveaux de Poursuite ressenti plus de Jovialité durant les jours durant lesquels ils ont reçu des niveaux de support particulièrement élevés. Ils ont aussi ressenti de hauts niveaux d'Hostilité durant les jours ou ils rapportent d'avoir reçu de plus bas niveaux de support qu'à l'habitude. De résultats similaires n'ont pas été obtenus avec les mesures de Sérénité, de Peur, ou de Culpabilité en tant que variables dépendantes, démontrant ainsi la spécificité des effets à la Jovialité et l'Hostilité. Les résultats sont adressés en termes de contributions théorique qui surviennent de l'intégration de la psychologie évolutionniste et la psychologie de la personnalité. De plus, nous avons identifiés des pistes de recherche pour le futur. Finalement des applications pratiques de styles d'échange social sont discutées en mettant de l'emphase sur les implications pour la conceptualisation et le traitement de troubles mentaux dans le contexte de la psychologie clinique.

The attribution of incentive salience to cues that become associated with drugs of abuse is a critical characteristic of individuals who may be vulnerable to drug addiction. Rodents with the propensity to sign track are thought to be vulnerable to drug abuse. The goal of the current work was to investigate whether sign trackers (STs) would acquire cocaine conditioned place preference (CPP) to a discrete cue using an avian species. In Experiment 1, sign and goal trackers (GTs) were first identified using a one third rank order split. Following identification, cocaine-CPP was conducted with a discrete cue in each end chamber. Contrary to previous research, results showed that GTs showed a CPP to the discrete cue but STs did not. Experiment 2 was conducted to determine whether sign and GTs had been misclassified with the rank order split. Experiment 2 compared the rank order method with a t-test method (absolute criterion). Misclassification of both sign and GTs occurred using the rank order split. The findings indicated that use of a more accurate method to identify sign and GTs may have led to different results for Experiment 1. The t-test method may be useful for models that require identification of STs.

This thesis addresses a specific problem of model-based segmentation; namely, the automatic identification and delineation of gross anatomical structures of the human brain based on their appearance in magnetic resonance images (MRI). The approach developed in this thesis depends on a general, iterative, hierarchical registration procedure and a 3-D digital model of human brain anatomy that contains both volumetric intensity-based data and geometric atlas data that co-exist in a brain-based stereotaxic coordinate system. The model contains features derived from an MRI atlas of gross neuroanatomy, that is the result of an intensity average of 305 brains created with an automatic stereotaxic registration procedure developed here.
The objective of this thesis is achieved by inverting the traditional segmentation strategy. Instead of matching geometric contours from an idealized atlas directly to the MRI data, segmentation is achieved by identifying the spatial transformation that, under certain constraints, best maps corresponding features between the model and a particular volumetric data set. After automatic recovery of the linear registration transform, the 3-D non-linear transformation is recovered by estimating the local deformation fields, recursively selected by stepping through the entire target volume in a 3D grid pattern, using cross-correlation of invariant intensity features derived from image data. This registration process is performed hierarchically, with each step in decreasing scale refining the fit of the previous step and providing input to the next. When completed, atlas contours defined in the model are mapped through the recovered transformation to segment structures in the original data set and identify them by name.
Experiments for registration and segmentation are presented using simple phantoms, a realistic digital brain phantom as well as human MRI data. The algorithm is used to estimate neuro-anatomical variability, to automatically segment cerebral structures and to create probabilistic representations of the same structures. Validation with manual methods shows that the procedure performs well, is objective and its implementation robust.

This study sought to identify the key determinants that lead individuals to participate in the transportation planning process. Two models of participation, one for the short-term and another for the long-term, were developed to test whether the key internal and external determinants are responsible for influencing a person's willingness to participate. The data for this study came from a mail-back survey that was administered to a random sample of 570 individuals throughout the State of Florida for a response rate of 37.37 percent. The results indicate that the internal motivational determinants exert more influence on a person's short-term willingness to participate as compared to a person's long-term willingness to participate. In addition, the external social capital determinants exert more influence on a person's long-term willingness to participate as compared to a person's short-term willingness to participate. However, only one of the three external citizenship orientation variables, participatory citizenship orientation, was found to be influential in determining a person's short-term willingness to participate. Recommendations were made for public managers to work collaboratively with the public as a participative facilitator, thereby opening up the decision-making process to the general public. One suggested course of action is for public managers to use existing civic organizations as a base for widening an agency's long-term planning outreach programs. In addition, suggestions for future research propose that qualitative studies delve in-depth into the positive/negative feelings related to participation, as well as look at how different public participation techniques may affect a person's willingness to participate, especially as it relates to different time frames.
Ph.D.
Other
Health and Public Affairs
Public Affairs: Ph.D.

Despite the well-established effectiveness of couple therapy for reducing distress and improving relationship satisfaction (Cohen, 1988; Christensen and Heavey, 1999), less than a fourth of couples seek couple therapy prior to divorce (Albrecht, Bahr, and Goodman, 1983; Wolcott, 1986). Rather, the majority of couples wait over 5 years before seeking therapy (Johnson et al., 2002). Barriers to seeking individual therapy are well established and are associated with decreased rates of therapy attendance and the negative consequences of untreated distress and mental health problems (Corrigan, 2004; Killaspy, Banerjee, King, and Lloyd, 2000; Vogel, Wade and Hackler, 2007). It is unclear as to whether the same barriers exist for individuals who are seeking couple therapy. This study examined the applicability of the Health Belief Model (HBM; Rosenstock, 1966), with the addition of demographic characteristics (gender, income, education, and religion) and contextualizing individual factors (relational distress and perceived stigma), to predict an individual in a committed relationship's (N =158) motivation to seek couple therapy. When controlling for demographic variables and contextualizing factors, the Health Belief Model factors of lower barriers and lower benefits were predictive of higher motivation to seek couple therapy. Throughout all iterations of the model, lower income and lower relational distress were also associated with higher rates of motivation to seek couple therapy. This research indicates that barriers, including high levels of relational distress, impact an individual's motivation to seek couple therapy. Further investigation of the application of the HBM factors to mental health, including research into more systemic measurements of these factors, is needed. Future research should also identify other potentially contextualizing factors, as the overall model accounted for a relatively small amount of variation in the individual's motivation to seek couple therapy.
Ph. D.

This study examined how comprehensively the Bolin and Trainer (1978) model of recovery reflects the recovery process of individuals and households. A review of the literature since 1978 suggested that various revisions and additions were warranted, but additional research was needed to examine these elements collectively. Rubin and Rubin?s (2012) Responsive Interviewing Model was employed to collect and analyze data related to the recovery process of individuals impacted by Hurricane/Superstorm Sandy to determine whether an updated model was appropriate. Interviews with twenty-one respondents representing non-governmental organizations involved in Sandy-related recovery efforts revealed the need for a revised model reflecting key aspects of the original model, revisions suggested by the literature, and a new addition based on the data collected through this study. A Revised Bolin and Trainer Model of Individual and Household Recovery was suggested and implications for the discipline and practice of emergency management discussed.

Social dynamics is concerned with the interactions of individuals and the resulting group behaviors. It models the temporal evolution of social systems via the interactions of the individuals within these systems. The availability of large-scale data in social networks and sensor networks offers an unprecedented opportunity to predict state changing events at the individual level. Examples of such events are disease infection, rumor propagation and opinion transition in elections, etc. Unlike previous research focusing on the collective effects of social systems, we want to make efficient inferences on the individual level.

Two main challenges are addressed: temporal modeling and computational complexity. The interaction pattern for each individual keeps changing over the time, i.e., an individual interacts with different individuals at different times. Second, as the number of tracked individual increases, the computational complexity grows exponentially with traditional sequential data analysis.

The contributions are: (i) leverage social networks and sensor networks data to make tractable inferences on both individual behaviors and collective effects in social dynamics. (ii) use the stochastic kinetic model to summarize dynamic interactions among individuals and simplify the state transition probabilities. (iii) propose an efficient variational inference algorithm whose complexity grows linearly with the number of tracked individuals M. Given the state space K of a single individual and the total number of time steps T, the complexity of naive brute-force approach is O(K^MT) and the complexity of existing exact inference approach is O(K^MT). In comparison, the complexity of the proposed algorithm is O(K ²MT). In practice, it requires several iterations to converge.

In the empirical study concerning epidemics dynamics, given wireless sensor network data collected from more than ten thousand people (M = 13,888) over three years (T = 3465), we use the proposed algorithm to track disease transmission, and predict the probability of infection for each individual (K = 2) along the time until convergence (I=5). It is more efficient than state of the art sampling methods, i.e., MCMC and particle filter, while achieving high accuracy.

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A distribuição dos recursos nos domicílios é importante para a compreensão do bem-estar material de seus integrantes e para a formulação de políticas redistributivas. Apesar da aparente importância da dimensão intrafamiliar da desigualdade, muito pouco tem sido feito para entender o quanto dos recursos do domicílio são apropriados pelos indivíduos que o compõem, e assim, tentar avaliar a pobreza individual. De fato, a avaliação da pobreza e da desigualdade, muitas vezes, assume uma distribuição igualitária dos recursos entre os membros do agregado familiar. Além disso, as medidas de pobreza não apenas negligenciam a distribuição dos recursos dentro dos domicílios, mas também os ganhos decorrentes do consumo conjunto. No entanto, a parcela de recursos domésticos dedicados a cada membro da família é difícil de identificar porque o consumo é medido ao nível do domicílio e os bens podem certamente ser compartilhados. Esta pesquisa tentou analisar o grau de desigualdade dentro das famílias e sua contribuição para os níveis de pobreza no contexto brasileiro. Em particular, estimou-se o processo de alocação de recursos e as economias de escala nos domicílios do Brasil usando um modelo coletivo de consumo das famílias. Mais especificamente, tentou-se analisar as parcelas de recursos de crianças e adultos e a relação com as economias de escala decorrentes do consumo conjunto e o processo de barganha dos pais, a fim de calcular uma medida direta da pobreza individual para o Brasil. A identificação da parcela de recursos dos membros do agregado familiar requer, além da observação de bens específicos dos adultos, a estimativa conjunta de curvas de Engel para domicílios de casais e solteiros. Esta estratégia de identificação difere do método tradicional de Rothbarth na medida em que é compatível com as economias de escala, bem como com o processo de barganha parental. A base de dados utilizada foi a Pesquisa de Orçamentos Familiares do Brasil (POF 2008-2009). Os principais resultados forneceram evidência de desigualdade e economias de escala dentro dos domicílios brasileiros, o que nos leva à rejeição do modelo unitário de consumo e da abordagem tradicional de Rothbarth no caso do Brasil, respectivamente. Os resultados também mostraram que a parcela dos gastos totais dos homens é ligeiramente maior do que as parcelas das mulheres para quase todas as estruturas familiares consideradas no presente trabalho. Por sua vez, a magnitude das parcelas das crianças, interpretadas como o custo dos filhos para os pais, é comparativamente menor. Outros resultados também mostraram como os recursos destinados a cada membro variam de acordo com o tamanho e a estrutura da família, e, em particular, como as medidas tradicionais de pobreza tendem a superestimar a incidência da pobreza infantil. Além disso, encontrou-se que a parcela de recursos dedicada às crianças aumenta com o número de crianças, mas a parcela média por cada criança tende a diminuir. Por outro lado, verificou-se que as economias de escala dos adultos são grandes e afetam as medidas de pobreza. Especificamente, a pobreza entre adultos é menor porque os pais são altamente compensados pelas economias de escala decorrentes do consumo conjunto. Apesar de os filhos comandarem uma parcela de recursos razoavelmente grande do agregado familiar, tal parcela não é suficiente para evitar que eles tenham taxas mais elevadas de pobreza do que os seus pais. Além disso, foi encontrado que as mães parecem contribuir com mais recursos para os filhos do que os pais, e por outro lado, não foram encontradas diferenças de gênero, mas sim diferenças etárias nas parcelas de recursos entre as crianças. Ainda, os resultados fornecem evidências indicando que o poder de barganha das mulheres dentro da família melhora com a idade, nível de educação e a participação no mercado de trabalho. No geral, a principal conclusão é que a desigualdade intrafamiliar é significativa. Uma consequência importante disso é que as medidas tradicionais per capita de pobreza, que, por construção, ignoram a desigualdade intrafamiliar, apresentam uma imagem enganosa da pobreza, em especial para as crianças. Finalmente, essas estimativas são importantes para as intervenções de políticas redistributivas, porque constituem medidas mais precisas do bem-estar material relativo dos brasileiros em domicílios de diversas composições. Igualmente, o fato de que é plausível medir as parcelas de recursos de cada membro das famílias é um passo muito útil para medir a pobreza individual e, assim, informar de forma mais precisa aos formuladores de políticas que estão focados na redução da pobreza.
The distribution of resources within households is crucial to the understanding of its members’ material well-being and for the design of redistributive policies. Although the apparent importance of the intra-household dimension of inequality, very little research has focused on how much of the family resources are dedicated to each member, and thereby attempting to assess individual poverty. In fact, the assessment of poverty and inequality often assumes an equal distribution of resources among household members. Moreover, poverty measures not only neglect the distribution of resources within families, but also the gains from joint consumption. However, the share of household resources devoted to each family member is hard to identify, because consumption is measured at the household level and goods can indeed be shared. This research attempted to analyze the extent of inequality within households and its contribution to levels of poverty in the Brazilian context. In particular, we estimated the process of resources allocation and economies of scale in households from Brazil using a collective model of household consumption. More specifically, we attempted to analyze the resource shares of children and adults in relation with the scale economies of joint consumption and the parental bargaining in order to calculate a direct measure of individual poverty for Brazil. The identification of the household member’s resource share requires the observation of adult-specific goods and a joint estimation on couples and singles. This identification strategy differs from the traditional Rothbarth method, in that it is compatible with economies of scale as well as with parents’ bargaining. The database used was Pesquisa de Orçamentos Familiares (POF 2008-2009). The main results provide evidence of inequality and economies of scale within Brazilian households, which leads us to the rejection of the unitary model and the traditional Rothbarth approach for Brazil, respectively. Our findings also showed that men’s share of total expenditures is slightly larger than women's shares for almost all the family structures considered here. The magnitude of children’s shares, interpreted as the cost of children for the parents, is in turn comparatively smaller. We also showed how resources devoted to each household member vary by family size and structure, and we find that, particularly, standard poverty measures tend to overstate the incidence of child poverty. Furthermore, we found that the share of resources devoted to children rises with the number of children, but the average share per child tends to decrease. On the other hand, we found that adult's scale economies are large and affect poverty measures. Specifically, adult poverty is smaller because parents are highly compensated by the scale economies due to joint consumption. Despite that the children command a reasonably large share of household resources, such share is not enough to avoid having higher rates of poverty than their parents. In addition, we found that mothers seem to contribute more resources than fathers to children, and we do not find evidence of gender but age differences in children’s resource shares. Also, results provide evidence indicating that women’s bargaining power within the household improves with their age, level of education and participation in the labor market. Overall, our main finding is that there is substantial intra-household inequality. One important consequence of this is that standard per-capita poverty measures, which by construction ignore intra-household inequality, present a misleading picture of poverty, particularly for children. Finally, our estimates are important for redistributive policy interventions, because they constitute more accurate measures of the relative material welfare of Brazilians in households of varying composition. Furthermore, the fact that it is plausible to measure of each member’s resource shares within households is a very useful step in measuring individual poverty, and thus informing in a more precise way to policy makers which are focused on poverty alleviation.
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Machine learning models are becoming more and more powerful and accurate, but their good predictions usually come with a high complexity. Depending on the situation, such a lack of interpretability can be an important and blocking issue. This is especially the case when trust is needed on the user side in order to take a decision based on the model prediction. For instance, when an insurance company uses a machine learning algorithm in order to detect fraudsters: the company would trust the model to be based on meaningful variables before actually taking action and investigating on a particular individual. In this thesis, several explanation methods are described and compared on multiple datasets (text data, numerical), on classification and regression problems.
Maskininlärningsmodellerna blir mer och mer kraftfulla och noggranna, men deras goda förutsägelser kommer ofta med en hög komplexitet. Beroende på situationen kan en sådan brist på tolkning vara ett viktigt och blockerande problem. Särskilt är det fallet när man behöver kunna lita på användarsidan för att fatta ett beslut baserat på modellprediktionen. Till exempel, ett försäkringsbolag kan använda en maskininlärningsalgoritm för att upptäcka bedrägerier, men företaget vill vara säkert på att modellen är baserad på meningsfulla variabler innan man faktiskt vidtar åtgärder och undersöker en viss individ. I denna avhandling beskrivs och förklaras flera förklaringsmetoder, på många dataset av typerna textdata och numeriska data, på klassificerings- och regressionsproblem.

A model of gendered social control is presented based on the concept of logic statements which undergird the two overarching discourses surrounding the social problem of domestic violence: a social service discourse and a feminist discourse. Two arguments are made. First, there will be a coherence between discourse and the program agendas offered at domestic violence shelters, a coherence between discourse or program agenda and organizational variables, and a coherence between discourse or program agenda and funding sources. The most robust empirical finding supported the coherence between a social service discourse and a program agenda based on the logic statements associated with masculinism, liberal individualism and medicalization. The second argument posits functional relationships among discourse, program agenda, the organizational variables and the funding variables. Social service programs were predicted by social service discourse and by federal monies and feminist programs were predicted by the number of women sheltered; social service discourse was predicted by social service programs and feminist discourse was predicted by the number of women sheltered. These findings suggest that some program agendas put in place by domestic violence shelters may actually contribute to masculinism as a cultural practice.

Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains x, 153 p.; also includes graphics (some col.). Includes bibliographical references (p. 118-127). Available online via OhioLINK's ETD Center

Few things occupy as central a place in our lives as money. Although the study of money has a long history in the behavioral sciences, others have only recently begun examining this important topic. The purpose of this study was to explore the relationship between basic human need levels and money attitudes in a university-age cohort utilizing a theory of hierarchical needs. Needs theory, introduced by Abraham Maslow, suggests that as we interact with the environment we accumulate specific needs that motivate us to respond to life experiences. Three hundred thirty-eight college students attending Utah State University satellite campuses responded to a measure designed to examine an individual's attitudes toward money and achievement of needs (Maslow). Pilot study results validated the selection of modified versions of both Lim and Teo's Attitudes Toward Money Scale and Lester's Need Satisfaction Inventory as reliable instruments in assessing money attitudes and need achievement. Results confirmed relationships between money attitudes and human needs. Specifically, all of Maslow's needs appear to be strongly related to the money attitudes of evaluation and anxiety. In addition, men's and women's needs are highly correlated with obsession, budget, anxiety, and particularly evaluation. Associations of money attitudes with demographic variables such as gender, age, and income were also supported. For example, gender was statistically related to money attitudes of obsession, power, budget, and achievement. Age shared a strong relationship with obsession, budget, anxiety, and retention. Finally, power and evaluation were the money attitudes explaining the bulk of the variance in income. The findings of the study support the literature and point to the importance of understanding a client's money attitudes and level of need satisfaction. particularly from a counseling standpoint. Implications of the results and possible areas for future research are discussed.

Es conocido en la literatura de neuroimagen que las redes cerebrales funcionales reflejan rasgos personales. Estas características individuales, podrían interferir al caracterizar la cognición entendida como la manera en que se coordinan las redes para realizar una tarea, como mantener la atención, recordar, o procesar información visual. Cómo estos aspectos individuales coexisten con mecanismos generales es, por tanto, una pregunta clave en investigación sobre conectividad cerebral. Este trabajo estudia la relación entre marcadores de conectividad específicos tanto de sujetos, como de tareas. Se centra en dos escalas temporales distintas: la variabilidad entre sesiones, y las fluctuaciones rápidas producidas durante una sesión de adquisición. Utilizamos técnicas de machine learning para separar cuantitativamente las contribuciones de información del sujeto y del estado cognitivo a la conectividad. La metodología presentada nos permite extraer aquellas redes representativas de ambas dimensiones, así como profundizar en su evolución, sugiriendo las escalas temporales relevantes en la cognición.
És conegut en la literatura de neuroimatge que les xarxes cerebrals funcionals reflecteixen trets personals. Aquestes característiques individuals podrien interferir en caracteritzar la cognició entesa com la manera en què les xarxes es coordinen per realitzar una tasca, com mantenir l'atenció, recordar o processar informació visual. Cóm aquests aspectes individuals coexisteixen amb mecanismes generals, és, per tant, una pregunta clau en recerca sobre connectivitat cerebral. Aquest treball estudia la relació entre marcadors de connectivitat específics tant de subjectes, com de tasques. Se centra en dues escales temporals: la variabilitat entre sessions, i les fluctuacions ràpides produïdes durant una sessió d'adquisició. Utilitzem tècniques de machine learning per separar quantitativament les contribucions d'informació del subjecte i de l'estat cognitiu a la connectivitat. La metodologia presentada ens permet extreure aquelles xarxes representatives d'ambdues dimensions, així com aprofundir en la seva evolució, suggerint les escales temporals rellevants en la cognició.
There is consistent evidence in the neuroimaging literature that functional brain networks reflect personal traits. Individual specificity may interfere with the characterization of cognition, in terms of coordination of brain networks to perform a task, such as sustained attention, memory retrieval or visual information processing. How individual traits coexist with invariant mechanisms is, therefore, a key question in brain connectivity research. This work aims to examine the relationship between subject- and task-specific connectivity signatures. It focuses on two different timescales: day-to-day variability and faster fluctuations exhibited within a scanning session. We adopt a machine learning approach to quantitatively disentangle the contribution of subject information and cognitive state to the connectivity patterns. The proposed methodology allows us to extract the specific brain networks that support each of the two dimensions, as well as to delve into their changes over time, suggesting the relevant timescales for cognition.

At the end of 2005, the State Council of China passed ”The Decision on adjusting the Individual Account of Basic Pension System”, which adjusted the individual account in the 1997 basic pension system. In this essay, we will analyze the adjustment above, and use Life Annuity Actuarial Theory to establish the basic pension substitution rate model. Monte Carlo simulation is also used to prove the rationality of the model. Some suggestions are put forward associated with the substitution rate according to the current policy.

Teams play an important role in solving today’s complex problems. Disagreement exists about how teams should begin working on these problems to maximize performance. Ideation research encourages team members to produce many solutions to a problem and delay alignment of individual mental models of the problem. Team problem solving research advocates earlier and consistent alignment of individual mental models (team coherence). Problem solving research with individual solvers advocates clarifying and refining requirements for an ill-defined problem (representation construction), often via heuristics such as restating the problem in different ways. The purpose of this dissertation is to compare these different ways of starting on a problem, including the performance outcomes associated with each and the process by which these strategies produce their effect. The process by which teams identified goals for solving a problem was more important than a coherent team mental model for solution quality across two experiments with three-member teams solving case study problems. Experiment 1A & 1B shows that teams who collaborate early on a problem produce better solutions than those who collaborate after a delay. Team coherence is affected by working together with teammates, but does not impact solution quality. Groups of individuals who work alone the entire time (nominal teams) provided interim self-reports of their best solution that were more like their final problem solutions than other groups. In addition, members of interacting teams identify more “best” solutions of a problem when describing the solving process than “nominal” team (three-person aggregates working individually) members. Experiment 2 replicates Experiment 1 findings, and also shows that instructions to restate the problem had a similar positive effect on solution quality as early interaction. Working in isolation with restatement instructions provided comparable results to collaborating with team members. Team coherence, in contrast, was not related to solution quality. Both interaction and restatement improved quality by helping team members to consider alternative problem representations. Consideration of alternatives in turn may inoculate solvers from fixating on their first impressions of a best solution. Implications are discussed in terms of optimizing individual and team problem solving performance on ill-defined tasks.

Thesis (MBA)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Facilities are available to individual investors to enable them to invest directly in a multitude of investments without making use of investment brokers or financial advisors. Although this facility offers the benefit of reduced administration and management fees, it also puts the investor in a position where he is responsible for making his own investment decisions. Since Markowitz’s publication fifty years ago, it has been known that diversification is necessary in order to reduce the investor’s exposure to any unsystematic investment risk while still obtaining an acceptable return. Studies have shown that human behaviour has an impact on investment decisions and that human nature skews the individual’s perception of diversification and risk and the reality thereof. For this reason, the individual investor is better off making use of quantitative methods in order to ensure a properly diversified portfolio. Exchange traded products are passive, index tracking investments that trade on stock exchanges and pose benefits to individual investors owing to their low administrative costs and inherent levels of diversification. Individual investors are able to purchase exchange traded products such as exchange traded funds (ETFs), exchange traded notes (ETNs) and index tracking unit trusts through various means, including brokerage firms and online trading platforms. These platforms offer little advice to the individual investor on how to select the most suitable investment products and how each product will affect the risk profile of an investor’s portfolio. The purpose of this research assignment was to develop a portfolio optimisation tool that would help the investor obtain the optimal return for his desired level of risk, thereby ensuring efficient diversification. An optimisation model was developed by using performance data from 2009 to 2013 and the resultant optimised portfolio’s performance was evaluated for 2014. It was found that optimisation rendered acceptable results, provided that the covariances between the various ETFs showed equivalence year on year. This requirement limited the number of ETFs that could be included in the model. Improvements to the model were recommended, based on the results of similar research in the field of portfolio optimisation. Further research is proposed that would utilise other optimisation methods, other sources of data and comparisons that are more detailed.

The past decade of genetics research has been defined by the discovery of the profound effects non-coding genetic variation can have on the phenotypes that distinguish humans from each other and from our close evolutionary relatives. The full implications of this new understanding are largely unexplored, however, as modern ethics restricts experimentation in humans and most primates, rendering data from dynamic processes almost non-existent. The study of regulatory molecular dynamics has been changed entirely by the availability of protocols to generate iPSCs and differentiate them into adult cell types. The molecular basis of disease mechanisms, drug response, and developmental processes can now be studied in the relevant tissue, presenting an overwhelming spectrum of possible applications. Of particular interest to comparative biologists, long-standing questions about the relative conservation of early developmental states can now, for the first time, be ethically explored in closely related primates. In this dissertation, we first discuss evidence that iPSCs can faithfully model genetic variation, even when sourced from highly dysregulated cells. We then use an iPSC-based model to study the temporal profile of conservation between humans and chimpanzees during early endoderm development and identify patterns of divergence over developmental stages.

Dans leur vie quotidienne, chaque personne realise un plan d'activités individuelles et collectives. Lors de l’execution de ce plan, certaines perturbations impliquent la nécessité de modifier le plan. Dans cette thèse ces perturbations sont assimilées à des événements captes par les individus. Une approche de modélisation multi-agent est utiliser afin de reproduire par simulation le processus de re-planification des activités tant du point de vue individuel que collectif. Dans ce cadre, la relation entre une paire d ́episodes (trajet et activité) successifs est étudié lorsque le plan est confronte à des perturbations. Cette thèse utilise un arbre de decision pour construire l’ensemble des planifications possibles, ainsi que leurs pénalités respectives pour chaque episode. Concernant la re-négociation des trajets partagés, le conducteur et le passager doivent re-négocier les lieux de deposes et l’heure d’arrivée, en minimisant la distance entre ces lieux. Ainsi, une distance de tolerance est utilisée pour trouver le lieu alternatif, ainsi qu’une fonction d’utilité pour calculer le score de chaque choix alternatif. De plus, au cours du processus de re-négociation, la relation entre le passager et le conducteur est étudiée, notamment du point de vue de la pression temporelle. Ceci affecte le degré de concession du conducteur et du passager vis-à-vis des propositions de son partenaire
Daily activity schedule are popular for people duringdaily life. While, when executing the schedule on the real road network, there are always some disruptions disturbing the planned schedule. To deal with this problem, daily activity rescheduling is necessary. This thesis regards the disruptions from the activity schedule execution environment as unexpected events (uncertainties). It establishes agent-based models to simulate the activity rescheduling decision process from the aspects of individual activity rescheduling and joint trip renegotiating.For the individual activity rescheduling, the model in this thesis wants to explore the relationship between a pair of episodes (two connected episodes) under unexpected events. Therefore, activity type is an important factor to consider. This thesis uses the decision tree to search all the alternative choices, and then it calculates the penalty after applying for the choices for each episode. For the joint trip renegotiating problem, when unexpected events happens, such as congestion, the driver and passenger need to renegotiate the drop off place and arrival time. The passenger drop off place may be a place near to his original location, or a new location. This thesis proposes a tolerance distance to find the alternative drop off place, and it uses the utility function to calculate the score of each alternative choice. Also, during the renegotiation process, this thesis considers the relationship between the passenger and driver, and also the time pressure. Both of them affect the person’s concession degree to his opponent.The goal of this thesis is to simulate the activity rescheduling decision and its focus is the travel behavior. It defines the unexpected events that may occur during the activity schedule execution process, and it establishes models to deal with both the individual activity rescheduling decision-making process and joint trip renegotiating process. It would like to provide a method to simulate the rescheduling decision-making mostly closed to the reality, while, it still needs to be validated to the real case in the near future

Individual-based approaches in ecology provide a new approach to spatially explicit modelling. They are paralleled by the emergence of agent-based modelling in the field of artificial intelligence (AI) that is manifest in object-based approaches in a number of geographical disciplines, from hydrology to sociology. An individual-based approach to the simulation of organisms in a spatial context allows for a greater understanding of how individual-level behaviour and interactions result in population-level phenomena at the landscape-scale. Such models are inherently flexible and adaptable to other species or systems, and the model can be parameterised from biological behavioural information widely available in the literature. This research constructs, analyses and experiments with an individual-based model of aphid (Rhopalosiphum padi) population dynamics in agricultural landscapes during the autumn and winter. The model combines deterministic equations governing the development of the aphids with stochastic, behavioural rules. Several stages of model assessment validate the model: assessment at the conceptual, developmental and operational stages. The need for a solution for the model to cope with large population sizes led to experimentation with both mathematical and computational solutions to this problem. It was found that parallel computing to distribute the simulation across a 30-node Beowulf cluster was the most effective at increasing model efficiency whilst preserving model behaviour. Key scenarios are presented, that show the power of this approach in predicting potential impacts of agricultural landscape change, including the effects of crop management, marginal habitat configuration and pesticide regime. This research clearly demonstrates the potential of spatially explicit individual-based modelling to predict scenarios that may advise policy decision-makers as a landscape management tool.

Usando a generalização de Grauwin et al. [Ref. 3] do modelo de segregação de Schelling foi possível estudar, em um modelo simplificado, as consequências da guerra fiscal travada entre os estados de uma federação e os resultados da chamada guerra da taxa que os bancos adotaram depois de implantada a portabilidade de crédito bancário. No modelo de Grauwin a cidade é dividida em Q quarteirões e todos os quarteirões possuem a mesma função utilidade dependente da densidade u(m,?), que mede a satisfação dos agentes que ali residem. Inserimos um parâmetro de desordem m_b em um dos blocos para torná-lo mais atrativo que os demais. Ter um dos blocos diferente é a essência do modelo de guerra entre os quarteirões. Foi analisada uma aplicação deste modelo fazendo um paralelo com o cenário de uma guerra fiscal entre os estados de uma nação. Para tal, interpretamos os agentes econômicos como sendo as de indústrias (ou pessoas) que tomam decisões em busca de aumentar sua própria satisfação e os quarteirões como os estados de uma federação. A guerra fiscal é um instrumento usado por alguns estados brasileiros que reduzem impostos, cedem terrenos, fornecem infra-estrutura, etc para atrair investimentos na sua região. Esta guerra no primeiro momento pode ser benéfica para a sociedade, pois contribui para a descentralização da economia e reduz as diferenças de PIB e social entre os estados. Porém, em âmbito nacional, o embate econômico entre os estados geralmente resulta em perda de arrecadação para a nação. Um Estado totalmente desocupado, caso queira roubar empresas de Estados já consolidados, precisa dar muito mais incentivos para atrair investimento por conta da sua baixa população e consequentemente baixa utilidade. Neste trabalho tentamos quantificar os gastos que os Estados têm com este tipo de ação. Outra releitura dos resultados pode ser aplicada ao modelo de portabilidade de crédito, onde interpretamos os agentes econômicos de Grauwin como tomadores de empréstimo e os quarteirões como bancos de crédito ao varejo. A taxa de juros cobrada de cada banco dependerá do tamanho da carteira que este possui. Ter um banco com uma taxa de juros diferenciada o torna mais atrativo que os demais e este começa a roubar clientes dos outros bancos, contudo, o mercado reage e também reduz suas taxas, criando uma guerra da taxa no mercado financeiro. Estudando o cenário egoísta (onde o governo não desestimule a troca entre bancos) e supondo que a quantidade de tomadores no mercado seja suficientemente pequena, a dinâmica conduzirá a uma situação onde teremos apenas alguns bancos coexistindo e outros falindo. No limite egoísta o banco que se dispôs a dar incentivo terá a carteira maior que os demais bancos com taxas menores e isto vai ser invertendo à medida que o governo impõe comportamento mais altruísta da sociedade. Estudamos analiticamente os efeitos das variações da densidade e dos parâmetros (m) e altruísmo (a) no cenário global bem como os resultados esperados com a inserção de uma desordem (m_b) em um dos blocos. E por fim foram feitas simulações em computador para verificar se comportamento das dinâmicas em todos os cenários eram compatíveis com as soluções obtidas.
Using Grauwins generalization [Ref. 3] of Schelling\'s segregation model we study, in a simplified model, some consequences of the \"fiscal war\" waged between the states of a federation, and of the rate tax generated by the recent Brazilian Central Bank regulation of bank credit portability. In Grauwins model the city is divided into blocks and all blocks have the same utility function, which measures the satisfaction of agents living there and depends on the density of agents. We introduced a disorder parameter in one of the blocks to make it more attractive than the others, in order to mimick the essential igredient of competition between states or banks. We first analyze an application of this model in the scenario of a fiscal war between the states of a nation. We interpret blocks as the states of a federation and economic agents as the industries (or people) who make decisions seeking to increase their own satisfaction. The fiscal war is an instrument used by some Brazilian states consisting in reducing taxes, subsidize land, provide infrastructure, etc in order to attract investment. This war at first can be beneficial for society as it contributes to the decentralization of the economy and reduces the differences of GDP and social discrepancies between states. Nationwide, however, the economic struggle between states usually results in loss of revenue at the global level. A vacated state, in order to attract agents already established elsewhere, need to give more incentives to attract investment because of its low population and consequently low utility. In this work we try to quantify the costs that states have with this kind of action. Another analysis of the results can be applied to a bank credit portability model, where we interpret economic agents as customers and blocks as retail credit banks. The interest rate levied on each bank will depend on the size of the portfolio of that bank. Having a bank with a differentiated interest rate makes it more attractive than others, and it begins to \"steal\" customers from other banks.However, those react and also reduce their rates, creating a \"war tax\" in the financial market. Studying the selfish scenario (where the government doesnt discourage a client from taking his/her debt to another bank), and assuming that the number of customers in the market is sufficiently small, the dynamics leads to a situation where we have just a few coexisting banks, the others having gone bankrupt. In the selfish limit the bank that was willing to give encouragement will have the largest portfolio while offering lower interest rates than the others, but this will be reversed as the government imposes a more altruistic behavior to the clients. We study analytically the effects, at the global level, of variations in the density, in the altruism parameter and in the parameter determining the utility function at saturation, as well as the effects of introducing disorder in one or more blocks. Finally, computer simulations were performed to check that the dynamic behavior in all scenarios was consistent with those obtained solutions.

Individuals engage in competitive and cooperative interactions with conspecifics. Furthermore, within any population of interacting individuals there are typically consistent differences among-individuals in behavioural traits. Understanding the importance of both these types of individual-specific behaviours allows us to understand why populations are structured as they are, why individuals show apparently limited behavioural flexibility, and how these elements link to population-level properties. I used extensive video camera monitoring of a population of wild field crickets (Gryllus campestris) to study the interactions and behaviours of uniquely identified individuals. I studied the shyness, activity and exploration of individuals of this population across contexts: from young to old and between captivity and the wild. This allowed me to confirm that individuals were relatively consistent across their adult lifetimes for all three traits, but only consistent between captivity and the wild for activity and exploration. I then found that high activity levels were positively related to high mating rates and short lifespans. Crucially, lifetime mating success was not related to activity level, indicating that the trade-off between lifespan and mating success was sufficient to allow variation in activity level to persist across generations. I also found that cricket social network structure is stable across generations despite the complete turnover of individuals every year. This social network structure influences sexual selection, with some male crickets heavily involved in networks of both pre- and post-copulatory competition, yet males are unable to use pre-copulatory competition to avoid post-copulatory competition. Additionally, positive assortment by mating rate between males and females may reduce the fitness of males with high mating rates, as they face stronger sperm competition. Finally, I used actor-based models to determine the factors predicting cricket social network structure and to test and reject the social-niche hypothesis for the maintenance of among-individual variation in behaviour. I also demonstrated that little else is needed in a stochastically changing network aside from positive assortment by mating rate to simulate a population with a similar skew in mating success to the one observed in the real cricket population. These results give insights into the importance of trade-offs and stochasticity in maintaining the extensive variation in the natural world.

Tumour spheroid experiments have been used to study the growth of tumours and inform treatment methods for the last 50 years. In this thesis, a novel individual-based mathematical model of tumour spheroid experiments with cell-cycle labelling is developed to study how tumour spheroids with human melanoma cells evolve under laboratory conditions. Qualitative and quantitative analyses demonstrate that mathematical model data compare well with experimental results, and quantitative information about nutrient availability in the spheroid, which is difficult to measure experimentally, is made accessible.

碩士
朝陽科技大學
營建工程系碩士班
94
Using non-destructive testing （NDT） methods to evaluate the integrity and quality of newly-built piles is a mature technique and is adopted as a standard procedure by many countries. However, many difficulties have been encountered in applying these kind of techniques into evaluating the integrity of existing piles. The dominant factors include the effects of pile caps, pile group and superstructures. However, the NDT techniques such as the Sonic Echo, Impulse Response, Ultra Seismic and the Parallel Seismic methods have the advantages of being convenient, economical, and efficient. They can be used as the front line testing means once the related researches are matured. The main objective of this research is to investigate the feasibility of applying non-destructive testing techniques in evaluating the integrity of piles. Model piles with artificial detects were constructed and tested with impact hammer of various sizes and different tip materials. The ability of NDT technigues such as Sonic Echo, Impulse Response, Ultra Seismic, and Parallel Seismic methods in detecting these defects were compared in this thesis.

碩士
國立雲林科技大學
營建與物業管理研究所
99
Nowadays, property management companies are facing intensive competition among the market. In order to enhance service quality, companies provide 24-hour service. However, the personnel cost of security staffs usually takes about 85% of total operating cost. In order to reduce personnel expenditure and sustain a good morale, it would be a big challenge for companies to schedule shifts efficiently. So far, the conventional way for shift scheduling is based on supervisor’s working experience without considering any preference or will of the security staff. The purpose of this research is to take both personnel cost and security staff’s preference into account while scheduling shift. A novice integer programming model is developed to find out the best shift schedule, which is subjected to the objective of the lowest personnel cost and the goal of satisfying most of individual staff preferences. Through case study, model applicability is verified. Research finding shows that this model not only meets staff’s expectation, also minimizes the personnel budget.