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Un'Analisi della Variazione Lessicale Regionale Nell’Inglese di California Attraverso le Ricerche in Rete Limitate per Sito / AN ANALYSIS OF REGIONAL LEXICAL VARIATION IN CALIFORNIA ENGLISH USING SITE-RESTRICTED WEB SEARCHESASNAGHI, COSTANZA 12 March 2013 (has links)
Lo studio esamina la variazione lessicale regionale in forma scritta nell’inglese standard in California. Attraverso ricerche in rete limitate a 336 siti di giornali online con sede in 270 città in California, vengono raccolti i valori di 45 variabili continue di alternanze lessicali e quindi calcolati come proporzioni. Tecniche statistiche di autocorrelazione spaziale globale e locale analizzano i valori. I risultati delle analisi, riportati in 90 mappe, confermano la distribuzione regionale delle variabili in California. Le 45 variabili lessicali sono poi esaminate con tecniche statistiche multivariate per individuare le relazioni linguistiche tra le città della California esaminate. L’analisi fattoriale, che rappresenta il 50,5% della variazione nei dati, evidenzia tre aree nella distribuzione regionale lessicale: nord/sud, urbano/rurale, e aree centrali e basso meridionali/aree alto meridionali e del nord. L’analisi dei cluster gerarchica distingue inoltre sei regioni dialettali principali in California: quella del Nord, quella di Sacramento-Santa Cruz, quella della San Francisco Bay Area, quella centrale, quella alto meridionale, e quella basso meridionale. Cinque mappe multivariate sono fornite nella tesi. La spiegazione dei risultati si basa sia su modelli di insediamento storico che su una spiegazione socio-culturale, che si riflettono nel linguaggio in California. / The study examines regional lexical variation in written Standard California English. The valuesof 45 continuous lexical alternation variables are gathered through site-restricted web searches in 336 online newspaper websites based in 270 locations in California and then calculated as proportions. Statistical techniques analyze global and local spatial autocorrelation values. The results of the analysis, reported in 90 maps, confirm the regional distribution of the variables in California. The 45 lexical variables are then analyzed with multivariate techniques to identify the linguistic relations between the surveyed California cities. Factor analysis, which accounts for 50.5% of the variation in the data, highlights three areas in the regional lexical distribution: north/south, urban/rural, central and lower southern/upper southern and northern areas. The hierarchical cluster analysis also distinguishes six major dialect regions in California: the North dialect region, the Sacramento-Santa Cruz dialect region, the San Francisco Bay Area dialect region, the Central dialect region, the Upper Southerns dialect region, and the Lower Southern dialect region. Five multivariate maps are provided in the thesis. The explanation of the results is based both on historical settlement patterns and on a socio-cultural explanation, which are reflected in the language in California.
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Towards the identification of a neighbourhood park typology : a conceptual and methodological explorationBird, Madeleine 08 1900 (has links)
Peu d’études ont évalué les caractéristiques des parcs pouvant encourager l’activité physique spécifiquement chez les jeunes. Cette étude vise à estimer la fiabilité d’un outil d’observation des parcs orienté vers les jeunes, à identifier les domaines conceptuels des parcs capturés par cet outil à l’aide d’une opérationnalisation du modèle conceptuel des parcs et de l’activité physique et à identifier différents types de parcs.
Un total de 576 parcs ont été évalués en utilisant un outil d’évaluation des parcs. La fiabilité intra-juges et la fiabilité inter-juges de cet outil ont été estimées. Une analyse exploratoire par composantes principales (ACP) a été effectuée en utilisant une rotation orthogonale varimax et les variables étaient retenues si elles saturaient à ≥0.3 sur une composante. Une analyse par grappes (AG) à l’aide de la méthode de Ward a ensuite été réalisée en utilisant les composantes principales et une mesure de l’aire des parcs. L’outil était généralement fiable et l’ACP a permis d'identifier dix composantes principales qui expliquaient 60% de la variance totale. L’AG a donné un résultat de neuf grappes qui expliquaient 40% de la variance totale. Les méthodes de l’ACP et l’AG sont donc faisables avec des données de parcs. Les résultats ont été interprétés en utilisant l’opérationnalisation du modèle conceptuel. / Few studies have characterized park features that may be appealing for youth physical activity (PA). This study assesses the reliability of a youth-oriented direct-observation park assessment tool; identifies park domains captured by the tool using an operationalized conceptual model of parks and PA, and identifies distinct park types.
576 parks were audited using a park observation tool; intra- and inter-rater reliability were estimated. Exploratory principal component analysis (PCA) was conducted and variables were retained if they loaded at 0.3 or higher. A cluster analysis (CA) was conducted using the principal components and park area. The tool was found to be reliable and PCA yielded ten principal components explaining 60% of the total variance. The CA yielded a nine-cluster outcome explaining 40% of the total variance. PCA and CA were found to be feasible methods to use with park data. The operationalization of the conceptual model helped interpret these results.
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Hapsite® gas chromatograph-mass spectrometer (GC/MS) variability assessment /Skinner, Michael A. January 2005 (has links) (PDF)
Thesis (M.S.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).
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Clusterização e visualização espaço-temporal de dados georreferenciados adaptando o algoritmo marker clusterer: um caso de uso em Curitiba / Clustering and visualization spatial-temporal georeferenced data adapting the marker clusterer algorithm: a use case in CuritibaRodriguez Vila, Juan Jose Franklin 16 December 2016 (has links)
CNPq; CAPES; / Cinquenta por cento da população mundial vive em cidades, e a expectativa para 2050 é de que essa porcentagem chegue a 70% (WHO, 2014). As cidades consomem 75% dos recursos naturais e de energia do mundo, e geram 80% dos gases-estufa responsáveis pelo efeito estufa; considerando que, ocupam apenas 2% do território mundial (Signori, 2008). As cidades são também o palco de grande parte dos problemas ambientais globais (Gomes, 2009), e é no contexto urbano onde a dimensão social, econômica e ambiental convergem mais intensamente (European Commission, 2007). Esse crescimento populacional, tem influências sociais, econômicas e ambientais que representam um grande desafio para o desenvolvimento sustentável do planejamento urbano. Os conceitos de sistemas de informação geográfica, cidades inteligentes, dados abertos, algoritmos de clusterização e visualização de dados, permitem entender diversas questões em relação a atividade urbana nas cidades. Em particular, se torna importante a variável “onde”: onde existe tráfego e quais são os horários mais frequentes; onde é necessário realizar modelagem de espera residencial, comercial e industrial de acordo com o crescimento populacional para o plano de uso da terra; quais são os tipos de negócios que mais cresceram em cada bairro e qual é a relação entre eles. Para este fim, esta dissertação apresenta um sistema web-mobile que permite entender o crescimento espaço-temporal e econômico dos alvarás de restaurantes dos bairros Centro, Batel e Tatuquara da cidade de Curitiba nas últimas três décadas (1980 até 2015), realizando clusterização e visualização de uma grande quantidade de dados abertos georreferenciados. Em termos de resultados alcançados destacam-se: 1) capacidade de resolver problemas computacionais de sobreposição de pontos sobre um mapa, 2) capacidade de entender o crescimento econômico dos alvarás e qual é a relação entre as diversas categorias e entre os bairros, 3) tempo de execução inferior a 3 segundos para 99% das consultas espaciais executadas, 4) 80,8% dos usuários em fase de avaliação consideram que a solução proposta permite uma melhor identificação e visualização de dados georreferenciados, e 5) possibilita a integração de novas fontes e tipos de dados. / Fifty percent of the world's population live in cities, and the expectation until 2050 is that it reaches 70% (WHO, 2014). Cities consume 75% of the world's natural resources and energy, and generate 80% of greenhouse gases responsible for the greenhouse effect, considering that they occupy only 2% of the world's territory (Signori, 2008). Cities are also the scene of most of the global environmental problems (Gomes, 2009), and it is in the urban context where the social, economic and environmental dimension converge more intensely (European Commission, 2007). This population growth has social, economic and environmental influences that represent a great challenge for the sustainable development of urban planning. The concepts of geographic information systems, smart cities, open data, clustering and data visualization algorithms allow us to understand several questions regarding urban activity in cities, especially, understand the variable "where" things happen. For example: where there is traffic and what time is the most frequent, where it is necessary to perform residential, commercial, industrial standby modeling according to population growth for the land use plan, what are the types of businesses that grew the most in each neighborhood and what is the relationship between them. For this purpose, the following thesis presents a web-mobile system that allows us to understand the spatiotemporal and economic growth of the restaurant licenses of districts Centro, Batel and Tatuquara of Curitiba for the last three decades, performing clustering and visualization of a large amount of open georeferenced data. In terms of achieved results, we can highlight: 1) ability to solve computational problems of overlapping points representing business on a map, 2) ability to understand the economic growth of restaurants licences and what is the relationship between different categories and between districts, 3) execution time less than 3 seconds for 99% of the spatial queries executed, 4) 80.8% of users in evaluation phase consider that the proposed solution allows a better identification and visualization of georeferenced data, and 5) it allows the integration of new sources and types of data.
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Self-tracking a běhání: sociologická analýza / Self-tracking and running: a sociological analysisHanzlová, Radka January 2018 (has links)
This thesis focuses on self-tracking, which mean monitoring and recording information about oneself using digital technologies and its use by runners in the Czech Republic. The main aim of this thesis is to describe the Czech running community through a detailed sociological analysis, and to answer a question: Why runners use self-tracking and how they benefit from it? The theoretical part firstly deals with the topic of self-tracking itself, then examines the uses and gratifications theory and the theory of online communities. The analytical part is devoted to description, analysis and interpretation of the results of the author's own survey, in which 844 runners of whom 754 practice self-tracking participated. Several hypotheses concerning sociodemographic structure, running characteristics, motivation, gratifications and safety were formulated. Five key motives (self-control, orientation to result, self-improvement, habit and social interaction) that lead runners to use self-tracking devices were identified through exploratory factor analysis. The motives vary based on gender and running characteristics (experience with running, runner's level, frequency of running, trainer) that also represent the main influencing factor for self-tracking in general. Self-tracking is closely related to sharing...
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Houding teenoor televisie-advertensie : 'n psigometriese perspektief / Attitude towards television commercials : a psychometric perspectiveJoubert, Johan Pierre Retief 06 1900 (has links)
Text in Afrikaans / Dit is belangrik vir bemarkingsorganisasies om die effek van bemarkingsaksies en meer
spesifiek reklame te meet van wee eskalerende koste-oorwegings. Wat die rol van
reklame in verbruikersgedrag betref, is die belewing van of houding-teenoor-reklame
konsepte van sentrale be lang. Aangesien die term bel ewing meer beskrywend is oor die
impak wat advertensies op verbruikers het word hierdie term algemeen gebruik. Hierdie
studie ondersoek die konsep advertensiewaardering en ontleed die invloed daarvan op
advertensiebelewing.
Die kyker-responsprofiel soos deur Schlinger (1979) ontwikkel, word algemeen gebruik
om televisiekykers se houding teenoor televisie-advertensies te meet.
Hierdie studie poog om die toepaslikheid en geldigheid van die kyker-responsprofiel
onder Suid-Afrikaanse televisiekykers te ondersoek. Die navorsingsmetode het uit twee
fases bestaan.
Die eerste fase was meer kwalitatief van aard, en ondersoek kykers se kognitiewe
struktuur van houding teenoor televisie-advertensies. Die teoretiese uitgangspunt tydens
hierdie fase is persoonlike-konstrukteorie. Repertoriumrooster onderhoude is met 50
volwasse televisiekykers (ouer as 16 jaar) uit verskillende taalgroepe gevoer. Daar is bevind dat kykers gemiddeld ses konstrukte gebruik ten einde die waarderingsvlak van
advertensies te bepaal. 313 Konstrukte is in totaal deur die 50 respondente ontlok.
Hierdie konstruke is deur individuele roosterontledings en ooreenkomsanalise tot 'n
aantal konstrukgroepe gereduseer. Beskrywings van konstrukgroepe is aan die hand van
n literatuurnavorsing gedoen. Die konstrukgroepe (tevredenheid, vermaaklikheid,
interessantheid, sosialiteit, duidelikheid, realiteit, tempo en emosialiteit) toon 'n mate van
ooreenstemming met die sewe Schlinger basisfaktore. Die onderliggende indiwiduele
konstrukte wat vermaaklikheid, sosialiteit tempo en interessantheid beskryf, toon hoe
korrelasies met waardering wat daarop dui dat waardering meer as net vermaaklikheid
behels.
Fase twee was meer kwantitatief van aard en het die ontleding van 382
kykerresponsprofiele behels. 'n Faktorontleding van die 32 Schlinger-items het sewe
basisfaktore tot gevolg. Die eerste vyf faktore (vermaaklikheid, verwarring, relevante
nuus, handelsmerkversterking en empatie) beskik oor soortgelyke faktorladings as
faktorontledings wat in die V.S.A. gedoen is. Hierdie bevinding dui daarop dat die
affektiewe belewingstruktuur van televisiekykers in Suid-Afrika grootliks dieselfde is as
kykers in die Verenigde State. Die ander twee faktore (familiariteit en vervreemding) se
ladings verskil van die in die Verenigde State maar hierdie verskille kan gegewe die aard
van die advertensies ( bestaande en nuwe advertensiekonsepte) en die kruiskulturele aard
van Suid-Afrikaanse kykers verklaar word. Die Schlingeritems is statisties beskryf en ontleed deur die rol wat die tipe advertensie (bestaande versus nuwe), produk-kategorie en kulturele teikenmark speel in waardering van advertensies te ondersoeK. Nuwe konsepte is geneig om meer vermaaklik en relevant
te wees. Zulu, Sotho en Xhose kykers is geneig om advertensies as meer positief te
beleef. Kosmetika en medisinale-, korporatiewe- en motoradvertensies is verder minder
vermaaklik as voedsel en handelsadvertensies.
Die Schlingeritems wat advertensiewaardering die beste beskryf en voorspel is bepaal
deur bondelontledings en meerdimensionele verskaling. Daar is gevind dat waardering
die mate waartoe 'n advertensie aan die vermaaklikheids, empatie en relevante nuus
doelwitte voldoen sonder om verwarrend, vervreemdend of oorbekend te wees.
Dit wil voorkom of daar twee dimensies bestaan wat die meeste variansie in
Schlingeritems verklaar naamlik waardering (positief of negatief) en relevansie.
Bondelontleding dui verder daarop dat 'n positiewe persepsie van 'n geadverteerde
handelsmerk kykers ontvanklik maak om meer van 'n advertensie te hou of te waardeer. / It is important that, given escalating cost considerations, marketing organisations
determine the effect that their marketing efforts have. With regard to the role of
advertising m consumer behaviour, attitude towards commercials is of utmost
importance. This study examined the liking of television advertisement concept and
analyses the effect of this concept on attitude towards television advertising.
The viewer response profile as developed by Schlinger (1979) is commonly used to
evaluate viewer's attitude towards television commercials. This study attempted to
investigate the applicability and validity of this instrument amongst South African
television viewers.
The study consisted of two phases. Phase one was more qualitative in nature and
investigated the viewer's cognitive structure of attitude towards television commercials.
The theoretical approach used during this phase was personal construct theory. It was
found that viewers on average use six constructs to evaluate whether they like or dislike
commercials. 313 Constructs were elicited and based on individual grid analyses and
correspondence analysis a reduced number of construct groups was identified. These construct groups ( contentness, entertainment, interesting, sociality, clearness,
reality, emotionality, and tempo) show a measure of similarity to the seven Schlinger
factors or dimensions. The individual constructs, which make up entertainment,
sociality, emotionality, tempo and interesting, show high levels of correlation with
advertisement liking. This finding suggests that advertisement liking involve more than
pure entertainment.
Phase two was more quantitative and consisted of analysing 382 viewer response
profiles. A factor analysis of the 32 items, which make up the viewer response profile,
resulted in seven factors. The first five factors (entertainment, confusion, relevant news,
brand reinforcement and empathy) show similar factor loading to factor analytical studies
done in the United State of America. The other two factors (familiarity and alienation)
show different loading to the United States of America study but these differences could
be explained given the nature of commercials tested (existing commercials and new
commercial concepts) and the cross cultural nature of South African viewers.
The Schlinger items were analysed in greater detail by investigating the role which type
of commercial (existing versus new), product category and cultural target market play in
liking of commercials.
New concepts are proven to be more entertaining, creative and relevant. Zulu and Sotho
viewers are likely to be more positively disposed towards television commercials while
cosmetic, medicine, corporate and motor vehicle commercials are less entertaining than
food and commercial commercials. Those Schlinger items, which best describe and predict commercials liking were
determined by using cluster and multi dimensional scaling techniques.
It is apparent from this analysis that likability is the extent to which the objective of
entertainment, empathy or relevant news is achieved without confusion, alienation or
familiarity. Cluster analysis furthermore suggests that a positive perception of an
advertised brand predispose viewers to higher levels of commercial liking. Multi
dimensional scaling suggest two dimensions explaining most of the Schlinger factor
variance namely liking (positive of negative) and relevance. / Industrial and Organisational Psychology / D. Com. (Bedryfsielkunde)
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Análise da rede de transporte público de Curitiba como rede complexa / Analysis of Curitiba’s public transportation system as complex networkSilva, Emerson Luiz Chiesse da 05 July 2017 (has links)
Os sistemas de transporte público (STP) são entidades complexas formados por vários subsistemas (administração, gerenciamento de frota, manutenção de veículos, segurança, bilhetagem, engenharia de tráfego, urbanismo, recursos humanos, entre outros). Os STP oferecem diversas rotas de veículos coletivos para atender os usuários do serviço mas o planejamento das rotas é uma das áreas que exigem atenção e são de difícil avaliação de desempenho. Estas rotas formam malhas que podem ser abstraídas como grafos, em vários tipos de representações, como por exemplo as paradas associadas aos nós e uma rota (ou linha) de veículos associada a uma sequência de conexões ou arestas que interligam estes pontos. Da representação do STP como grafos, é possível extrair informações importantes a partir de métricas como dimensões, centralidades, pesos, entre outras, e classificar o STP em algum modelo já estudado. A partir do modelo estabelecido, melhorias no sistema podem ser propostas e uma posterior re-análise dos resultados das novas medidas no modelo pode justificar ou não uma possível implementação destas propostas no sistema real. Neste trabalho um sistema de transporte público foi analisado como rede complexa, especificamente o STP de Curitiba, no estado do Paraná, Brasil. Demonstrou-se que este sistema, em representação espaço-L, possui características de rede complexa do tipo scale free. Tal sistema possuía onze categorias de rotas de ônibus, sendo que as principais categorias foram analisadas como rede complexa para avaliar sua influência nas métricas do sistema como um todo. Adicionalmente, combinando as métricas de redes complexas com o método k-means de agrupamento nesse STP, foram identificadas regiões geográficas da cidade que possuem as maiores e menores características de conectividade para os habitantes de Curitiba, sinalizando possíveis degradações de atendimento do sistema de transporte. O estudo revelou que, em Curitiba, a região central é a melhor servida, enquanto que algumas regiões periféricas no sudeste e nordeste da cidade são pouco favorecidas de transporte público. / Public transportation systems (PTS) are complex entities composed by many different subsystems (administration, vehicles management and maintenance, security, taxing, trafic engineering, urbanism, human resources and others). PTS offers various routes using public sharing vehicules to serve users, and the route planning is one of the issues that demand attention and has hard performance assessment. This routes form meshes in many types of representation, e. g., vehicle stops as nodes and a route as a sequence of links that connect their nodes. From PTS representation as graphs, it is possible to extract valuable informations from metrics as dimensions, centralities, weight and others, and to classify this PTS within some model already studied. Towards established models, system enhancements can be proposed and posterior re- analysis of such improved systems can justify or not their implementation in the real system. At this work a public transport system was analysed as Complex Network, specifically Curitiba’s PTS, (Paraná, Brazil). Here it was demonstrated that this system, represented in l-space, has network characteristics of scale-free networks. This system has eleven bus routes categories, in which main categories were analysed as complex networks to assess their influence on whole system metrics. Additionally, combining both complex network metrics and k-means method on this PTS, geographic areas of the city showing best and worst connectivity characteristics for the inhabitants of Curitiba were identified, which allows detecting potential transportation system weakness. This study revealed that Curitiba’s central region is best served, and some periphericals areas at southeast and northeast have low public transportation service.
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Análise da rede de transporte público de Curitiba como rede complexa / Analysis of Curitiba’s public transportation system as complex networkSilva, Emerson Luiz Chiesse da 05 July 2017 (has links)
Os sistemas de transporte público (STP) são entidades complexas formados por vários subsistemas (administração, gerenciamento de frota, manutenção de veículos, segurança, bilhetagem, engenharia de tráfego, urbanismo, recursos humanos, entre outros). Os STP oferecem diversas rotas de veículos coletivos para atender os usuários do serviço mas o planejamento das rotas é uma das áreas que exigem atenção e são de difícil avaliação de desempenho. Estas rotas formam malhas que podem ser abstraídas como grafos, em vários tipos de representações, como por exemplo as paradas associadas aos nós e uma rota (ou linha) de veículos associada a uma sequência de conexões ou arestas que interligam estes pontos. Da representação do STP como grafos, é possível extrair informações importantes a partir de métricas como dimensões, centralidades, pesos, entre outras, e classificar o STP em algum modelo já estudado. A partir do modelo estabelecido, melhorias no sistema podem ser propostas e uma posterior re-análise dos resultados das novas medidas no modelo pode justificar ou não uma possível implementação destas propostas no sistema real. Neste trabalho um sistema de transporte público foi analisado como rede complexa, especificamente o STP de Curitiba, no estado do Paraná, Brasil. Demonstrou-se que este sistema, em representação espaço-L, possui características de rede complexa do tipo scale free. Tal sistema possuía onze categorias de rotas de ônibus, sendo que as principais categorias foram analisadas como rede complexa para avaliar sua influência nas métricas do sistema como um todo. Adicionalmente, combinando as métricas de redes complexas com o método k-means de agrupamento nesse STP, foram identificadas regiões geográficas da cidade que possuem as maiores e menores características de conectividade para os habitantes de Curitiba, sinalizando possíveis degradações de atendimento do sistema de transporte. O estudo revelou que, em Curitiba, a região central é a melhor servida, enquanto que algumas regiões periféricas no sudeste e nordeste da cidade são pouco favorecidas de transporte público. / Public transportation systems (PTS) are complex entities composed by many different subsystems (administration, vehicles management and maintenance, security, taxing, trafic engineering, urbanism, human resources and others). PTS offers various routes using public sharing vehicules to serve users, and the route planning is one of the issues that demand attention and has hard performance assessment. This routes form meshes in many types of representation, e. g., vehicle stops as nodes and a route as a sequence of links that connect their nodes. From PTS representation as graphs, it is possible to extract valuable informations from metrics as dimensions, centralities, weight and others, and to classify this PTS within some model already studied. Towards established models, system enhancements can be proposed and posterior re- analysis of such improved systems can justify or not their implementation in the real system. At this work a public transport system was analysed as Complex Network, specifically Curitiba’s PTS, (Paraná, Brazil). Here it was demonstrated that this system, represented in l-space, has network characteristics of scale-free networks. This system has eleven bus routes categories, in which main categories were analysed as complex networks to assess their influence on whole system metrics. Additionally, combining both complex network metrics and k-means method on this PTS, geographic areas of the city showing best and worst connectivity characteristics for the inhabitants of Curitiba were identified, which allows detecting potential transportation system weakness. This study revealed that Curitiba’s central region is best served, and some periphericals areas at southeast and northeast have low public transportation service.
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Técnicas de inteligência artificial aplicadas ao método de monitoramento de integridade estrutural baseado na impedância eletromecânica para monitoramento de danos em estruturas aeronáuticas / Artificial intelligence techniques applied to the impedance-based structural health monitoring technique for monitoring damage in aircraft structuresPalomino, Lizeth Vargas 03 July 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The basic concept of impedance-based structure health monitoring is measuring the
variation of the electromechanical impedance of the structure as caused by the presence of
damage by using patches of piezoelectric material bonded on the surface of the structure (or
embedded into). The measured electrical impedance of the PZT patch is directly related to
the mechanical impedance of the structure. That is why the presence of damage can be
detected by monitoring the variation of the impedance signal. In order to quantify damage, a
metric is specially defined, which allows to assign a characteristic scalar value to the fault.
This study initially evaluates the influence of environmental conditions in the impedance
measurement, such as temperature, magnetic fields and ionic environment. The results show
that the magnetic field does not influence the impedance measurement and that the ionic
environment influences the results. However, when the sensor is shielded, the effect of the
ionic environment is significantly reduced. The influence of the sensor geometry has also
been studied. It has been established that the shape of the PZT patch (rectangular or
circular) has no influence on the impedance measurement. However, the position of the
sensor is an important issue to correctly detect damage. This work presents the development
of a low-cost portable system for impedance measuring to automatically measure and store
data from 16 PZT patches, without human intervention. One fundamental aspect in the
context of this work is to characterize the damage type from the various impedance signals
collected. In this sense, the techniques of artificial intelligence known as neural networks and
fuzzy cluster analysis were tested for classifying damage of aircraft structures, obtaining
satisfactory results. One last contribution of the present work is the study of the performance
of the electromechanical impedance-based structural health monitoring technique to detect
damage in structures under dynamic loading. Encouraging results were obtained for this aim. / O conceito básico da técnica de integridade estrutural baseada na impedância tem a ver com o
monitoramento da variação da impedância eletromecânica da estrutura, causada pela presença
alterações estruturais, através de pastilhas de material piezelétrico coladas na superfície da
estrutura ou nela incorporadas. A impedância medida se relaciona com a impedância mecânica
da estrutura. A partir da variação dos sinais de impedância pode-se concluir pela existência ou
não de uma falha. Para quantificar esta falha, métricas de dano são especialmente definidas,
permitindo atribuir-lhe um valor escalar característico. Este trabalho pretende inicialmente avaliar
a influência de algumas condições ambientais, tais como os campos magnéticos e os meios
iônicos na medição de impedância. Os resultados obtidos mostram que os campos magnéticos
não tem influência na medição de impedância e que os meios iônicos influenciam os resultados;
entretanto, ao blindar o sensor, este efeito se reduz consideravelmente. Também foi estudada a
influencia da geometria, ou seja, do formato do PZT e da posição do sensor com respeito ao
dano. Verificou-se que o formato do PZT não tem nenhuma influência na medição e que a
posição do sensor é importante para detectar corretamente o dano. Neste trabalho se apresenta
o desenvolvimento de um sistema de medição de impedância de baixo custo e portátil que tem a
capacidade de medir e armazenar a medição de 16 PZTs sem a necessidade de intervenção
humana. Um aspecto de fundamental importância no contexto deste trabalho é a caracterização
do dano a partir dos sinais de impedância coletados. Neste sentido, as técnicas de inteligência
artificial conhecidas como redes neurais e análises de cluster fuzzy, foram testadas para
classificar danos em estruturas aeronáuticas, obtendo resultados satisfatórios para esta tarefa.
Uma última contribuição deste trabalho é o estudo do comportamento da técnica de
monitoramento de integridade estrutural baseado na impedância eletromecânica na detecção de
danos em estruturas submetidas a carregamento dinâmico. Os resultados obtidos mostram que
a técnica funciona adequadamente nestes casos. / Doutor em Engenharia Mecânica
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Prevalência da rinossinusite crônica através de inquéritos domiciliares na cidade de São Paulo / Prevalence of chronic rhinosinusitis by household surveys in the city of São PauloRenata Ribeiro de Mendonça Pilan 01 October 2014 (has links)
INTRODUÇÃO: A rinossinusite crônica (RSC) é uma doença comum na população, com documentada repercussão na qualidade de vida e com alto custo direto em saúde pública que engloba consultas médicas, exames complementares e radiológicos, internações hospitalares, cirurgias e tratamento medicamentoso. Apresenta também custos indiretos como diminuição da produtividade no trabalho e absenteísmo. Os dados epidemiológicos sobre rinossinusite crônica são escassos; e as definições de rinossinusite crônica estabelecidas, as metodologias das pesquisas e as taxas de respostas diferem muito entre si. A pesquisa epidemiológica da RSC é importante para avaliar sua distribuição, analisar seus fatores de risco e fornecer dados para promoção de políticas de saúde pública, entretanto não existem dados epidemiológicos sobre a prevalência desta doença em nossa população. MÉTODO: Foi realizado um inquérito transversal de base populacional (survey) com plano de amostragem complexo realizado em dois estágios: setor censitário e domicílio. Entrevistas foram conduzidas pessoalmente, através de entrevistadores treinados, em 2003 indivíduos com idade de 12 anos ou mais, residentes da cidade de São Paulo. O questionário incluiu o diagnóstico de rinossinusite crônica segundo os critérios epidemiológicos estabelecido pelo EP3OS. Dados demográficos, diagnóstico médico autorreferido de doenças respiratórias (asma, sinusite, rinite), tabagismo, renda familiar, nível educacional e características do domicílio também foram incluídas. RESULTADOS: A taxa de resposta total foi de 87,8%. A idade média foi de 39,8 anos (DP= 21, 12-92), 45,33% do sexo masculino. A prevalência da rinossinusite crônica na cidade de São Paulo foi de 5,51% (IC 95%=3,99-7,58). Não existiu uma diferença estatisticamente significativa na prevalência segundo o sexo. Foi encontrada uma associação estatisticamente significativa do diagnóstico de RSC com o diagnóstico de asma (OR=3.88), de rinite (OR=5,02) e com o subgrupo de baixa renda (OR=2,28) As prevalências de RSC segundo o estado tabágico (p=0,43), consumo tabágico em anos.maço (p=0,26) e tabagismo passivo intradomiciliar (p=0,18) não apresentaram uma diferença estatisticamente significativa. CONCLUSÃO: A prevalência estimada de RSC na população da cidade de São Paulo é de 5,51% (aproximadamente 500.000 indivíduos). Foi encontrada associação com rinite, asma e com o subgrupo de baixa renda. Não houve associação com tabagismo / INTRODUCTION: Chronic rhinosinusitis (CRS) is a common disease with proven repercussions on quality of life and a high burden of direct costs to public health, which included physician visits, laboratory tests and medical imaging, hospital admissions, surgical intervention, and medical treatment. It also carries indirect costs, such as decreased productivity in the workplace and absenteeism. Epidemiological data on CRS are scarce, and the established definitions of CRS, study methods, and response rates vary widely. Epidemiological research into CRS is important to assess its distribution, analyze its risk factors, and provide data to subsidize public health policies; however, there are no epidemiological data on the prevalence of this disease in our population. METHOD: This was a cross-sectional population-based survey with a complex cluster sampling plan carried out in two stages: census sector and household. Interviews of 2,003 individuals, aged 12 years or older and living in the city of São Paulo, were conducted face-to-face by trained investigators. The questionnaire included diagnosis of CRS according to the epidemiological criteria established by EP3OS. Demographic data, a self-reported history of physician-diagnosed respiratory diseases (asthma, sinusitis, rhinitis), smoking, family income, educational attainment, and household characteristics were also included. RESULTS: The overall response rate was 87.8%. The mean age was 39.8 years (SD = 21 years; range = 12-92), and 45.33% were male. The prevalence of CRS in the city of São Paulo was 5.51% (95%CI = 3.99-7.58). There was no statistically significant difference in prevalence between the sexes. Statistically significant associations were found between diagnosis of CRS and diagnosis of asthma (OR=3.88), of rhinitis (OR=5.02), and belonging to the low-income subgroup (OR=2.28) The prevalences of CRS according to smoking status (p=0.43), tobacco intake in pack years (p=0.26) or exposure to passive smoking in the household (p=0.18) did not exhibit a statistically significant difference. CONCLUSION: The estimated population-wide prevalence of CRS in the city of São Paulo is 5.51% (approximately 500,000 individuals). Associations were found with rhinitis, asthma, and low income. There was no association with smoking
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