This thesis examines Instagram users and how they create an identity, and their interaction with other users. The aim of this study is to understand what we do with Instagram and what Instagram does with us in our everyday lives, and what the effects of the medium entails. This thesis is based on theories of identity, hyper- reality and effects of the development of social media. The method used in this study is qualitative focus group interviews with five women and five men, where the answers are transcribed and analyzed to gain an understanding of the effects and the impact of Instagram in their lives. We chose to interview both men and women, and therefore we have also had the gender issue in mind, but it has not been the main focus of this study. The results we reached in this study is that Instagram is mainly used to keep updated and that the medium provides both positive and negative effects. We also discovered that individuals are not one hundred percent themselves on Instagram. The conclusion we can draw is that people play different roles on Instagram of different purposes, and that we live in a hyper- reality that brings both good and bad. We can also conclude that even though people today have the power to present themselves in the way they want to, we see tendencies that gender representation is present in a stereotypical way.

Due to the unprecedented spatial and temporal resolution they offer, wireless sensor networks are considered an enabling technology for the distributed monitoring of industrial, military, and natural environments. As these systems migrate into vastly different and novel applications, new constraints are discovered that affect network reliability and utility. For example, wireless sensors are typically statically deployed and, unlike mobile systems, cannot move to a new location for better radio reception. As a result, the signal fades caused by non-optimal environmental conditions can increase the outage probability of the system, potentially rendering the network unreliable and ineffectual. Stochastic models that quantify link reliability and the effectiveness of diversity methods are often employed to understand the impact of such fading. However, the performance of these models applied to wireless sensor networks is entirely dependent on the appropriateness of the model with respect to the environment. This work first presents an empirical study of the propagation environment for a wingless, rotary aircraft, showing that the wireless environment within exhibits frequency-selective fading much more severe than predicted by current worst-case models (i.e., Rayleigh). An analysis is then given of the effectiveness of several diversity methods operating within such environments (referred to as hyper-Rayleigh). These fade mitigation techniques are simple enough to be employed for use with low-complexity wireless sensor hardware, and include spatial diversity, polar diversity, two-element passive combining, and two-element phased combining. Two-element phased combining is further developed by examining the effect that smaller element spacing has on diversity gain. A demonstration of a wireless

The forced Oscillation Technique (FOT) can be used to measure lung impedance continuously during breathing. However, spectral overlap between the breathing waveform and the applied flow oscillation can be problematic if the frequency content of spontaneous breathing is unknown. This problem motivated us to develop a modification to the FOT system called the Tracked Breathing Trainer. The modification uses biofeedback to constrain subjects to breathe at a single predetermined frequency. This thesis investigates the engineering and physiological aspects of the modification we made. We studied 8 adult non-asthmatic and 8 adult asthmatic subjects. Three 16 s perturbatory flow oscillation signals ranging from 1-40 Hz were used on the subjects. Each subject received three trials per perturbation for both spontaneous and tracked breathing. We then fitted a resistance-elastance-inertance model of the lung to each data set. For non-asthmatic subjects, the average resistance (R) and elastance (E) values for the first spontaneous breathing trial were 2.5±0.15 cmH2O.s.ml-1 and 18.1±3.55 cmH2O.ml-1, and for the third spontaneous breathing trial were 2.4±0.12 cmH2O.s.ml-1 and 21.8±4 cmH2O.ml-1. R and E for the first tracked breathing trial were 2.3±0.21 cmH2O.s.ml-1 and 33.6±7.4 cmH2O.ml-1, and for the third tracked breathing trial were 2.4±0.14 cmH2O.s.ml-1 and 25.75±4.3 cmH2O.ml-1, respectively. For asthmatic subjects, the average R and E values for the first spontaneous breathing trial were 3.32±0.68 cmH2O.s.ml-1 and 39.13±9.8 cmH2O.ml-1, and for the third spontaneous breathing trial were 3.12±0.15 cmH2O.s.ml-1 and 39.91±6.2 cmH2O.ml-1. R and E for the first tracked breathing trial were 2.86±0.15 cmH2O.s.ml-1 and 32.47±4.1 cmH2O.ml-1, and for the third tracked breathing trial were 2.86±0.21 cmH2O.s.ml-1 and 33.89±10 cmH2O.ml-1, respectively. These results show that R was consistently lower during tracked breathing than spontaneous breathing in both non-asthmatic and asthmatic subjects. However, an increase in E was observed during tracked breathing. We suspect this effect may have resulted from dynamic hyperinflation. These results also show that R and E are reproducible with both spontaneous and tracked breathing, and that R and E were not noticeably different between both breathing maneuvers. We conclude that using biofeedback to control the breathing pattern during application of the FOT in normal subjects does not significantly affect impedance measurements, and thus may be useful for avoiding spectral overlap between FOT perturbations and the breathing pattern.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Ce travail concerne une catégorie de robot mobile manipulateur omnidirectionnel bionique, en l’occurence le RobotinoXT qui dispose d’un manipulateur bionique CBHA monté sur un robot mobile omnidirectionnel, nommée Robotino. D’abord, nous avons proposé un modèle cinématique direct de ce système en utilisant une méthode nommée « arc geometry ». Celle-ci a été validée grâce à un banc d’expérimentation en ayant recours à une technique de trilatération. Pour atteindre cet objectif, les capteurs ont été calibrés. Concernant le problème de calibration des paramètres constants du modèle, il a été résolu en développant un algorithme d’optimisation incluant une méthode nommée SQP, validée via un manipulateur industriel à bras rigides. Puis, nous avons proposé un modèle cinématique inverse du CBHA en supposant que chaque vertèbre de celui-ci est assimilée à un robot parallèle. Ce modèle a été validé par les mesures réelles obtenues avec le manipulateur industriel, permettant la définition de l’espace de travail du robot. Enfin, nous avons implémenté une boîte à outils qui englobe les modèles développés dans ce travail. / This work deals with a particular class of mobile omnidrive-bionic manipulator robot namely RobotinoXT. It contains a bionic manipulator Compact Bionic Handling Assistant (CBHA) mounted over a mobile omnidrive robot Robotino. We first proposed a forward kinematic model of such a system by using an “arc geometry” method which was validated through a test bench using a trilateration technique. To achieve this purpose, the sensors were calibrated. For the model’s constant parameters calibration problem, this latter was resolved by developing an optimization algorithm which incorporates a SQP method, validated via an industrial manipulator with rigid links. Then, we proposed an inverse kinematic model of the CBHA by assuming that each backbone of it, is assimilated to a parallel robot. This model was validated by real measurements obtained with the industrial manipulator, allowing defining the robot workspace. Finally, we implemented a toolbox which encompasses the models developed in this work.

Comment les relations consommateurs-marques peuvent-elles être développées en magasin ? Beaucoup de recherches sur les actions au point de vente les ont étudiées dans une perspective transactionnelle tandis que le marketing relationnel a prêté peu d'attention à ce qui se passe en magasin. Cependant le point de vente constitue un point de contact essentiel entre consommateurs et marques. Sur la base de deux études qualitatives et d'une étude expérimentale, cette recherche se concentre sur l'impact des actions en magasin sur les relations consommateurs-marques. Nous différencions les actions relationnelles des actions transactionnelles pour comparer leurs effets. L'application empirique est faite avec des marques de glaces distribuées en grandes et moyennes surfaces. Un questionnaire en ligne est mis en place pour tester des actions fictives que les marques pourraient mettre en œuvre. Nos résultats montrent l'intérêt pour les marques d'utiliser des actions relationnelles au point de vente. Les personnes exposées à des actions relationnelles attribuent plus souvent l'action à la marque. Ils perçoivent des efforts et une orientation relationnelle de la marque plus importants, ils s'identifient plus avec la marque, et déclarent ainsi une plus grande fidélité envers celle-ci. L'originalité de la recherche réside dans la prise en compte des actions en magasin dans une perspective relationnelle. Plus généralement, la conceptualisation et l'étude de l'impact de ce genre d'actions mettent en évidence une façon plus sociale de tenir compte des interactions entre les consommateurs et les marques. / How can be developed and impacted relationships in store ? Many researches have studied in-store actions in a transactional perspective while relationship marketing has paid little attention to what happens in store. However, stores constitute a key point of contact between consumers and brands. Based on two qualitative studies and an experimental study, this research focuses on the impact of in-store actions on consumer-brand relationships. It differentiates relational and transactional actions and compares their effects. The empirical application involves ice cream brands distributed in the super-hypermarket channel. An online questionnaire is implemented to test fictitious actions that brands could implement. Our results show the interest for manufacturers brands to use relational in-store actions. Individuals exposed to relational in-store actions attribute more frequently the effort to the manufacturer. They perceive stronger efforts and brand expression, they identify more with the brand, and declare a higher loyalty to the latter. The originality of the research lies in the consideration of in-store actions in a relational perspective. More generally, the conceptualization and the study of the impact of these kinds of actions highlight a more social way to consider interactions between consumers and brands in the marketplace.

La presente es una investigación y aplicación metodológica que tiene como objetivo general el estudio del discurso publicitario peruano contemporáneo asociado a relaciones sociales de la sociedad de consumo. El tema se encargará de mostrar, exponer y estudiar las diferencias discursivas y narrativas entre los nuevos modos de producción publicitaria (propios del hiperconsumismo) y los modos “tradicionales” publicitarios (propios de la sociedad de consumo) mediante el estudio semiótico de las campañas de Inca Kola (motor y motivo) & BCP (decisiones de la vida) en el Perú del año 2011 como representantes de tales discursos. La investigación considera el estudio de las relaciones discontinuas del consumo como principal factor que determina la significación de la publicidad. Partiendo de esta primera noción y adoptando la tesis de una figura ternaria de la sociedad de consumo (la fase 1 (1880-1945), la fase 2 (1950-1985) y la fase 3 (1985 - ¿?)), es que se relacionará por tanto a la fase 1 y 2 con la llamada “publicidad tradicional” y la fase 3 con la “publicidad no tradicional” o hiperpublicidad. Estos tres tipos de discurso no se eliminan, sino que conviven y funcionan en la comunicación contemporánea adecuándose a los códigos sociales logrando modular su sentido. La investigación sustenta, partiendo de esta discontinuidad o cambio en las prácticas de consumo, que se han suscitado modificaciones en la comunicación publicitaria actual ocasionando que la narrativa y discurso de la publicidad tradicional produzca lecturas y sentidos contrarios o tangenciales respecto a dicha comunicación publicitaria. / This is a research and methodological application that has as a general objective the study of contemporary Peruvian advertising discourse associated with social relations of the consumer society. The theme will be responsible for showing, exposing and studying the discursive and narrative differences between the new modes of advertising production (typical of hyper-consumerism) and the "traditional" advertising modes (typical of the consumer society) through the semiotic study of advertising campaigns Inca Kola (motor and motive) & BCP (life decisions) in Peru in 2011 as representatives of such speeches. The investigation considers the study of the discontinuous relations of consumption as the main factor that determines the significance of advertising. Starting from this first notion and adopting the thesis of a ternary figure of the consumer society, namely phase 1 (1880-1945), phase 2 (1950-1985) and phase 3 (1985 -?). Is which will therefore relate to phase 1 and 2 with the so-called "traditional advertising" and phase 3 with "non-traditional advertising" or hyper-advertising. These three types of discourse are not eliminated, but they coexist and function in contemporary communication, adapting to the codes and social foundations and modulating their meaning. The research is based on this discontinuity or change in consumer practices that have led to changes in the current advertising communication causing the narrative and discourse of traditional advertising to produce readings and contrary or tangential views regarding such advertising communication. / Tesis

Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The size, diversity and continued growth of the World Wide Web combine to make its understanding difficult even at the most basic levels. The focus of our work is in developing novel methods for measuring and analyzing the Web which lead to a deeper understanding of its performance. We describe a methodology and a distributed infrastructure for taking measurements in both the network and end-hosts. The first unique characteristic of the infrastructure is our ability to generate requests at our Web server which closely imitate actual users. This ability is based on detailed analysis of Web client behavior and the creation of the Scalable URL Request Generator (SURGE) tool. SURGE provides us with the flexibility to test different aspects of Web performance. We demonstrate this flexibility in an evaluation of the 1.0 and 1.1 versions of the Hyper Text Transfer Protocol. The second unique aspect of our approach is that we analyze the details of Web transactions by applying critical path analysis (CPA). CPA enables us to precisely decompose latency in Web transactions into propagation delay, network variation, server delay, client delay and packet loss delays. We present analysis of pe1formance data collected in our infrastructure. Our results show that our methods can expose surprising behavior in Web servers, and can yield considerable insight into the causes of delay variability in Web transactions. / 2031-01-01

O objetivo do presente estudo foi rever na literatura qual a definição de usuários frequentes/hiperutilizadores de serviços de urgência e emergência e conhecer as implicações destes usuários no serviço de urgência e emergência. Trata-se de um estudo realizado através Scoping Review, conforme a proposta do Joanna Briggs Institute (JBI). Resultados: Identificados 37 estudos e através da leitura do título e resumo, selecionados 27 para leitura na íntegra. Porém após a leitura detalhada foram excluídos 11 estudos que não apresentavam resultados e conclusões diretamente ligados à temática. Assim, a amostra final foi composta por 16 estudos. Entre estes, quatro eram brasileiros e escritos pelo mesmo autor. Não houve 18 consenso entre s autores quanto a definição do termo pesquisado, todavia indicaram como usuário frequente/hiperutilizador o paciente que utiliza o serviço de urgência e emergência mais de 3 vezes por ano. Conclusões: Há lacuna na literatura e não consenso sobre a temática. Há necessidade de mais estudos sobre o assunto para o delineamento de ações que possibilitem a melhora deste quadro / The purpose of this study is to review the definition done by the literature of frequent / hyper-users of immediacy and emergency services and to know the involvement of such users in the immediacy and emergency services. This is a study conducted through Scoping Review (Revisão de Alcance) as proposed by Joanna Briggs Institute (JBI). Results: 37 studies were identified and by means of reading the titles and abstracts, 27 were selected as for thorough reading. However after the itemized reading, 11 studies that did not bring forward results and conclusions directly related to the thematic, they were excluded. So the final specimen was consisted of 16 studies. Four amongst these were Brazilian and written by the same author. There was no consensus between the authors regarding definition of the searched word, nevertheless they indicated as frequent / hyper-user the patient who uses the immediacy and emergency services more than thrice a year. Conclusions: There is a vacuity in literature and no agreement on this thematic. There are needs for further studies on the topic for the delineation of actions to make improvements possible for this picture

Decision-tree induction is one of the most employed methods to extract knowledge from data. There are several distinct strategies for inducing decision trees from data, each one presenting advantages and disadvantages according to its corresponding inductive bias. These strategies have been continuously improved by researchers over the last 40 years. This thesis, following recent breakthroughs in the automatic design of machine learning algorithms, proposes to automatically generate decision-tree induction algorithms. Our proposed approach, namely HEAD-DT, is based on the evolutionary algorithms paradigm, which improves solutions based on metaphors of biological processes. HEAD-DT works over several manually-designed decision-tree components and combines the most suitable components for the task at hand. It can operate according to two different frameworks: i) evolving algorithms tailored to one single data set (specific framework); and ii) evolving algorithms from multiple data sets (general framework). The specific framework aims at generating one decision-tree algorithm per data set, so the resulting algorithm does not need to generalise beyond its target data set. The general framework has a more ambitious goal, which is to generate a single decision-tree algorithm capable of being effectively applied to several data sets. The specific framework is tested over 20 UCI data sets, and results show that HEAD-DTs specific algorithms outperform algorithms like CART and C4.5 with statistical significance. The general framework, in turn, is executed under two different scenarios: i) designing a domain-specific algorithm; and ii) designing a robust domain-free algorithm. The first scenario is tested over 35 microarray gene expression data sets, and results show that HEAD-DTs algorithms consistently outperform C4.5 and CART in different experimental configurations. The second scenario is tested over 67 UCI data sets, and HEAD-DTs algorithms were shown to be competitive with C4.5 and CART. Nevertheless, we show that HEAD-DT is prone to a special case of overfitting when it is executed under the second scenario of the general framework, and we point to possible alternatives for solving this problem. Finally, we perform an extensive experiment for evaluating the best single-objective fitness function for HEAD-DT, combining 5 classification performance measures with three aggregation schemes. We evaluate the 15 fitness functions in 67 UCI data sets, and the best of them are employed to generate algorithms tailored to balanced and imbalanced data. Results show that the automatically-designed algorithms outperform CART and C4.5 with statistical significance, indicating that HEAD-DT is also capable of generating custom algorithms for data with a particular kind of statistical profile / Árvores de decisão são amplamente utilizadas como estratégia para extração de conhecimento de dados. Existem muitas estratégias diferentes para indução de árvores de decisão, cada qual com suas vantagens e desvantagens tendo em vista seu bias indutivo. Tais estratégias têm sido continuamente melhoradas por pesquisadores nos últimos 40 anos. Esta tese, em sintonia com recentes descobertas no campo de projeto automático de algoritmos de aprendizado de máquina, propõe a geração automática de algoritmos de indução de árvores de decisão. A abordagem proposta, chamada de HEAD-DT, é baseada no paradigma de algoritmos evolutivos. HEAD-DT evolui componentes de árvores de decisão que foram manualmente codificados e os combina da forma mais adequada ao problema em questão. HEAD-DT funciona conforme dois diferentes frameworks: i) evolução de algoritmos customizados para uma única base de dados (framework específico); e ii) evolução de algoritmos a partir de múltiplas bases (framework geral). O framework específico tem por objetivo gerar um algoritmo por base de dados, de forma que o algoritmo projetado não necessite de poder de generalização que vá além da base alvo. O framework geral tem um objetivo mais ambicioso: gerar um único algoritmo capaz de ser efetivamente executado em várias bases de dados. O framework específico é testado em 20 bases públicas da UCI, e os resultados mostram que os algoritmos específicos gerados por HEAD-DT apresentam desempenho preditivo significativamente melhor do que algoritmos como CART e C4.5. O framework geral é executado em dois cenários diferentes: i) projeto de algoritmo específico a um domínio de aplicação; e ii) projeto de um algoritmo livre-de-domínio, robusto a bases distintas. O primeiro cenário é testado em 35 bases de expressão gênica, e os resultados mostram que o algoritmo gerado por HEAD-DT consistentemente supera CART e C4.5 em diferentes configurações experimentais. O segundo cenário é testado em 67 bases de dados da UCI, e os resultados mostram que o algoritmo gerado por HEAD-DT é competitivo com CART e C4.5. No entanto, é mostrado que HEAD-DT é vulnerável a um caso particular de overfitting quando executado sobre o segundo cenário do framework geral, e indica-se assim possíveis soluções para tal problema. Por fim, é realizado uma análise detalhada para avaliação de diferentes funções de fitness de HEAD-DT, onde 5 medidas de desempenho são combinadas com três esquemas de agregação. As 15 versões são avaliadas em 67 bases da UCI e as melhores versões são utilizadas para geração de algoritmos customizados para bases balanceadas e desbalanceadas. Os resultados mostram que os algoritmos gerados por HEAD-DT apresentam desempenho preditivo significativamente melhor que CART e C4.5, em uma clara indicação que HEAD-DT também é capaz de gerar algoritmos customizados para certo perfil estatístico dos dados de classificação