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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

A multi-method exploration of health disparities and COVID-19 incidence and mortality in the United States

Ali, S M Asger 09 December 2022 (has links) (PDF)
The 21st century experienced several health crises, especially in the form of infectious disease outbreaks such as the SARS outbreak in 2003, the H1N1 in 2009, and Ebola outbreaks in 2013. However, none has produced a worldwide socio-economic and health impact compared to the recent pandemic, known as COVID-19. As of October 4, 2022, more than 614 million cases with 6 million deaths have been reported worldwide. The United States is currently in the leading position with more than 98 million cases and 1 million deaths. The pandemic, however, did not impact the entire region similarly, and the infections and intensity varied with geographical and socio-economic characteristics. In this project, I used a multi-method approach to analyze the relationship between health disparities and COVID-19-related health outcomes in the USA and examine the influence of health disparities reporting on newspaper coverage of COVID-19. This assessment was performed in three ways. First, I have explored the relationship between Mississippi’s county-level COVID-19-related cases and deaths with the Center for Disease Control and Preventions’s Social Vulnerability Index (CDC SVI). Second, I have investigated the spatial pattern of COVID-19 in the USA and its associations with Social Determinants of Health (SDoH) by utilizing the County Health Rankings & Roadmaps (CHRR) dataset.Finally, I analyzed how news media reporting of key health determinants (i.e., age, race, income and gender) is framed, including the role of different stakeholders in the context of COVID-19. Findings revealed a statistical relationship between CDC’s Social Vulnerability Index (SVI) and Mississippi’s county-level COVID-19 cases and deaths. I also found that COVID-19 infections showed considerable spatial heterogeneity as the distribution of COVID-19 cases and deaths varies across the US counties and among the three largest waves. The multiple regression results also exhibited a temporal association between social determinants of health (SDH) indicators and COVID-19-related health outcomes across the USA. Finally, I found that the NYT coverage of COVID-19 dealt more with human interest, responsibility, and conflict than economic and morality frames. The findings revealed the vital role social determinants of health play during a health crisis, such as the COVID-19 pandemic.
142

Fouille de données spatiales et modélisation de linéaires de paysages agricoles / Spatial data mining and modelling of linears in agricultural landscape

Da Silva, Sébastien 11 September 2014 (has links)
Cette thèse s'inscrit dans un partenariat entre l'INRA et l'INRIA et dans le champs de l'extraction de connaissances à partir de bases de données spatiales. La problématique porte sur la caractérisation et la simulation de paysages agricoles. Plus précisément, nous nous concentrons sur des lignes qui structurent le paysage agricole, telles que les routes, les fossés d'irrigation et les haies. Notre objectif est de modéliser les haies en raison de leur rôle dans de nombreux processus écologiques et environnementaux. Nous étudions les moyens de caractériser les structures de haies sur deux paysages agricoles contrastés, l'un situé dans le sud-Est de la France (majoritairement composé de vergers) et le second en Bretagne (Ouest de la France, de type bocage). Nous déterminons également si, et dans quelles circonstances, la répartition spatiale des haies est structurée par la position des éléments linéaires plus pérennes du paysage tels que les routes et les fossés et l'échelle de ces structures. La démarche d'extraction de connaissances à partir de base de données (ECBD) mise en place comporte différentes étapes de prétraitement et de fouille de données, alliant des méthodes mathématiques et informatiques. La première partie du travail de thèse se concentre sur la création d'un indice spatial statistique, fondé sur une notion géométrique de voisinage et permettant la caractérisation des structures de haies. Celui-Ci a permis de décrire les structures de haies dans le paysage et les résultats montrent qu'elles dépendent des éléments plus pérennes à courte distance et que le voisinage des haies est uniforme au-Delà de 150 mètres. En outre différentes structures de voisinage ont été mises en évidence selon les principales orientations de haies dans le sud-Est de la France, mais pas en Bretagne. La seconde partie du travail de thèse a exploré l'intérêt du couplage de méthodes de linéarisation avec des méthodes de Markov. Les méthodes de linéarisation ont été introduites avec l'utilisation d'une variante des courbes de Hilbert : les chemins de Hilbert adaptatifs. Les données spatiales linéaires ainsi construites ont ensuite été traitées avec les méthodes de Markov. Ces dernières ont l'avantage de pouvoir servir à la fois pour l'apprentissage sur les données réelles et pour la génération de données, dans le cadre, par exemple, de la simulation d'un paysage. Les résultats montrent que ces méthodes couplées permettant un apprentissage et une génération automatique qui capte des caractéristiques des différents paysages. Les premières simulations sont encourageantes malgré le besoin d'un post-Traitement. Finalement, ce travail de thèse a permis la création d'une méthode d'exploration de données spatiales basée sur différents outils et prenant en charge toutes les étapes de l'ECBD classique, depuis la sélection des données jusqu'à la visualisation des résultats. De plus, la construction de cette méthode est telle qu'elle peut servir à son tour à la génération de données, volet nécessaire pour la simulation de paysage / This thesis is part of a partnership between INRA and INRIA in the field of knowledge extraction from spatial databases. The study focuses on the characterization and simulation of agricultural landscapes. More specifically, we focus on linears that structure the agricultural landscape, such as roads, irrigation ditches and hedgerows. Our goal is to model the spatial distribution of hedgerows because of their role in many ecological and environmental processes. We more specifically study how to characterize the spatial structure of hedgerows in two contrasting agricultural landscapes, one located in south-Eastern France (mainly composed of orchards) and the second in Brittany (western France, \emph{bocage}-Type). We determine if the spatial distribution of hedgerows is structured by the position of the more perennial linear landscape features, such as roads and ditches, or not. In such a case, we also detect the circumstances under which this spatial distribution is structured and the scale of these structures. The implementation of the process of Knowledge Discovery in Databases (KDD) is comprised of different preprocessing steps and data mining algorithms which combine mathematical and computational methods. The first part of the thesis focuses on the creation of a statistical spatial index, based on a geometric neighborhood concept and allowing the characterization of structures of hedgerows. Spatial index allows to describe the structures of hedgerows in the landscape. The results show that hedgerows depend on more permanent linear elements at short distances, and that their neighborhood is uniform beyond 150 meters. In addition different neighborhood structures have been identified depending on the orientation of hedgerows in the South-East of France but not in Brittany. The second part of the thesis explores the potential of coupling linearization methods with Markov methods. The linearization methods are based on the use of alternative Hilbert curves: Hilbert adaptive paths. The linearized spatial data thus constructed were then treated with Markov methods. These methods have the advantage of being able to serve both for the machine learning and for the generation of new data, for example in the context of the simulation of a landscape. The results show that the combination of these methods for learning and automatic generation of hedgerows captures some characteristics of the different study landscapes. The first simulations are encouraging despite the need for post-Processing. Finally, this work has enabled the creation of a spatial data mining method based on different tools that support all stages of a classic KDD, from the selection of data to the visualization of results. Furthermore, this method was constructed in such a way that it can also be used for data generation, a component necessary for the simulation of landscapes
143

Geographic Factors of Residential Burglaries - A Case Study in Nashville, Tennessee

Hall, Jonathan A. 01 November 2010 (has links)
This study examines geographic patterns and geographic factors of residential burglary at the Nashville, TN area for a twenty year period at five year interval starting in 1988. The purpose of this study is to identify what geographic factors have impacted on residential burglary rates, and if there were changes in the geographic patterns of residential burglary over the study period. Several criminological theories guide this study, with the most prominent being Social Disorganization Theory and Routine Activities Theory. Both of these theories focus on the relationships of place and crime. A number of spatial analysis methods are hence adopted to analyze residential burglary rates at block group level for each of the study year. Spatial autocorrelation approaches, particularly Global and Local Moran's I statistics, are utilized to detect the hotspots of residential burglary. To understand the underlying geographic factors of residential burglary, both OLS and GWR regression analyses are conducted to examine the relationships between residential burglary rates and various geographic factors, such as Percentages of Minorities, Singles, Vacant Housing Units, Renter Occupied Housing Units, and Persons below Poverty Line. The findings indicate that residential burglaries exhibit clustered patterns by forming various hotspots around the study area, especially in the central city and over time these hotspots tended to move in a northeasterly direction during the study period of 1988-2008. Overall, four of the five geographic factors under examination show positive correlations with the rate of residential burglary at block group level. Percentages of Vacant Housing Units and Persons below Poverty Line (both are indicators of neighbor economic well-being) are the strong indicators of crime, while Percentages of Minorities (ethnic heterogeneity indictor) and Renter Occupied Housing Units (residential turnover indictor) only show modest correlation in a less degree. Counter-intuitively, Percentage of Singles (another indicator of residential turnover) is in fact a deterrent of residential burglary; however, the reason for this deterrence is not entirely clear.
144

台灣地區鄉鎮市區生育率的空間與群集研究

許添容, Hsu, Tien-Jung Albert Unknown Date (has links)
生育率的降低是影響台灣地區近年來人口老化的顯著因素,因其變化幅度通常高於死亡率,對人口結構的影響較大。過去台灣地區生育率研究多為整體生育(如:總生育率、年齡別生育率)趨勢的模型,較少探討台灣各地區的特色。為能更深入瞭解台灣生育行為變化的特性,本文將生育率的研究層面由整體的資料,延伸至全台灣地區的各鄉鎮市區(不含離島地區有350個鄉鎮市區),希冀能更精確地找出與台灣地區生育率持續下降的相關因素。本文分為兩個部份,以鄉鎮市區的年齡別婦女生育率與年齡別有偶婦女生育率為研究對象,資料時間為1991、1992、2001、2002年:第一部份探討各鄉鎮市區的生育率數值間是否存在空間相關性,並進一步瞭解生育率較高(或較低)的地區是否有聚集的現象。第二部份則套用空間迴歸模型探討與生育率數值有關的因素(例如:人口密度、教育程度等),更精確且客觀地提供生育率未來趨勢的建議。 關鍵字:生育率、人口老化、空間統計、空間群聚、空間迴歸 / Both the fertility rates and mortality rates, especially the fertility rates, have been experiencing dramatic decreases in recent years, and the population aging thus has become one of the major concerns in Taiwan area. In order to identify the factors that are related to the decrease of fertility rates, unlike the previous works that deal with the aggregate national data, we will study the fertility pattern in township level. We will use the data of age-specific fertility rates and total fertility rates in 1991, 1992, 2001, and 2002 in 350 townships of Taiwan area. This study will be separated into two parts. First, we shall explore if there is spatial correlation among 350 townships of Taiwan area and detect if there are spatial clusters for higher fertility townships. The second part of this project will be focused on the spatial regression model. We will use this model to determine the factors that are highly correlated to the dropping of fertility rates. Key Words: Fertility Rates, Aging Population, Spatial Statistics, Spatial Clustering, Spatial Regression
145

Métodos de estadística espacial para evaluar la influencia de factores medioambientales sobre la incidencia y mortalidad por cáncer

Lertxundi Manterola, Aitana 16 February 2007 (has links)
Los objetivos de la tesis son:1.- Estudiar la relación entre la incidencia y mortalidad por cáncer y los factores medioambientales, en particular la contaminación atmosférica, controlando por factores socioeconómicos.2.- Utilizar aquellos métodos de estadística espacial apropiados para cada tipo de diseño.3.- Distinguir en los modelos las diferentes fuentes de extra-variabilidad espacial.4.- Controlar el problema de exceso de ceros inherente a alguna de las neoplasias de interés medioambientales.Conclusiones:- Tanto la incidencia como la mortalidad de las neoplasias, presentaron dos fuentes de extravariación. La extravariaicón espacial, por la que unidades vecinas tienden a presentar razones de incidencia/mortalidad similares, y la heterogeneidad no espacial. En general la extravariabilidad espacial ha resultado ser mucho mayor que la no espacial.- Para suavizar las RIE/RME correspondientes a variables con un porcentaje de ceros superior al40-50% debe utilizarse un modelo que capture este comportamiento.- El mejor modelo en términos de ajuste para recoger el exceso de ceros en las variables de interés ha resultado ser el modelo mixto de riesgo relativo.- Las RIE/RME suavizadas presentan un patrón geográfico claro sólo en algunas neoplasias de interés medioambiental.- Parte de la variabilidad remanente en las RIE/RME suavizadas pudo ser explicada mediante la introducción de variables explicativas, en particular la contaminación atmosférica y variables socioeconómicas.-Como los contaminantes atmosféricos fueron observados en un diseño geoestadístico y las neoplasias de interés mediambiental lo fueron en un diseño en rejilla se modelizó la superficie de exposición.- El efecto del contaminante en cada municipio/sección censal se aproximó introduciendo en el modelo el valor promedio en cada área y la variabilidad intra-área.- El efecto del contaminante se consideró aleatorio, en el sentido de que podría ser diferente en cada una de las áreas.- Las condiciones socioeconómicas fueron otra de las variables que redujeron la variabilidad remanente en las RIE/RME suavizadas.-Las variables explicativas observadas con un diseño en rejilla, como el índice de privación, se introdujeron en el modelo como efectos fijos.- El efecto de la privación sobre la incidencia y/o mortalidad por cáncer de tráquea, bronquios y pulmón, controlando por contaminantes atmosféricos, fue mayor en las mujeres que en los hombres.-Altas concentraciones de contaminantes atmosféricos aumentan el riesgo de padecer neoplasias de interés medioambiental, controlando por condiciones socioeconómicas. / The objectives of the Thesis are:1.- To study the relationship between incidence and cancer mortality and environmental factors, particularly atmospheric pollutio, using socioeconomic factors as control.2.- To use those methods of spatial statistics suitable for each type of design.3.- To distinguish different sources of spatial extra-variability between the models.4.- To control the problem of excess zeros inherent in some of the environment-related neoplasias.5.- To correctly introduce explanatory variables (according to the design oberved in them) of the geographical variability of the environment-related neoplasias in order to avoid possible biases.The conclusions are:-Both the incidence and mortality of environment-related neoplasias showed two wources of extra-variation: spatil extra-variation, in which neighbouring units tend to show similar incidence/mortality ratios, and non-spatial heterogeneity.-To smooth the SIR/SMR corresponding to variables with a precentage of zeros higher than 40-50% a model that captures this behaviour must be used.-The best model, in terms of fit, which recognises excess zeros in the variables of interest was the mixture relative risk model.-Smoothed SIR/SMR only showed a clear geographical pattern in some of the environment-related neoplasias.-Part of the remaining variability in the smoothed SIR/SMR could be explained by introducing explanatory variables, in particular atmospheric pollution and socieconomic variables.-As the atmospheric pollutants were observed in a geostatistical design and the environment-related neoplasias were studied in a lattice design, the exposure surface was modelled.-The effect of the pollutant in each municipality/electoral district as approached in the model by introducing the average value in each area and the intra-area variability.-Socioeconomic conditions were another of the variables that reduced the remaining variability in the smoothed SIR/SMR.-Explanatory variables observed with a lattice design, such as the privation index, were introduced in the model as fixed effects.-Greater privation, using atmospheric pollutans as control, implied a greater risk of suffering/dying from some of the environment-realted neoplasias in the three areas and periods studies.-The effect of privation on the incidence and/or mortality form throat, bronchial and lung cancer, using atmospheric pollutans as control, was greater in women than in men.
146

Temporal and spatial effects of a long term large scale alley farming experiment on water table dynamics : implications for effective agroforestry design

Noorduijn, Saskia L. January 2009 (has links)
[Truncated abstract] Removal of native vegetation to facilitate traditional agriculture practices has been shown to reduce ecosystem health, and restricts the native habitat. The subsequent change in the predominant vegetation water use patterns has altered the catchment water balance, and hydrology which results in land degradation through such processes of salinisation and water logging. More recently, moves toward more sustainable farming practices have been taken to help re-establish catchment hydrological equilibrium and improve catchment ecosystem services. Agroforestry is one such vehicle for this reestablishment. Perennial native vegetation has been shown to have a significant effect on catchment processes, mitigating any further degradation of the land. The effect of alternating native perennial tree belts with traditional broad acre agriculture in the alleys, referred to as alley farming, is investigated in this thesis due to the potential environmental and economic benefits that can result. This thesis investigates the impact of tree belts upon the water table and aims to gauge the ability of alley farming at controlling recharge within the low-medium rainfall zone on the valley floor. The basis of this research is the analysis of data collected from the Toolibin Alley Faring Trial. This experiment was established in 1995 to assess the viability of alley farming and incorporates different combinations of belt width, alley width and revegetation density. Transects of piezometers within each design have been monitored from October 1995 to January 2008. The piezometers were sporadically monitored over this period on a total of 39 dates. ... To further understand the response observed in the water table data, in depth hydrograph analysis of the control piezometer water levels was conducted. The statistical analysis demonstrates that the belts are having a very limited impact on the water table morphology, this is associated with the restricted use of groundwater by the perennial tree belts due to the poor quality, has been applied. This explains why there is limited signature of increased water table depth in the statistical analysis; there is evidence that alley farming as a means of reducing recharge may work however the overriding control on the trial are the rainfall trends rather than perennial growth. The low perennial biomass production at the site is an effect of limited water resources; however a significant distinction can be made between the water table depth and variability beneath high and low biomass belts. There are three main controls at the site; climate, development of perennial biomass and development of perennial root systems (both vertically and laterally). The regional climatic trends will influence water table levels creating a greater soil water storage capacity; therefore the contribution of soil water to transpiration rates will enable the tree belts to have some impact on recharge. Of the alley farming designs tested, the optimal planting density and belt/alley design, from an economic perspective, is identified as having a 4m belt width which generated the greatest biomass. As a means of controlling recharge at the site the effectiveness of alley farming is limited due the shallow saline water table limiting perennial growth.
147

Estatística Espacial aplicada na caracterização de áreas de risco para hipertensão e diabetes no estado de Minas Gerais / Spatial Statistics applied in the characterization of risk areas for hypertension and diabetes in the state of Minas Gerais

Pinto, Eliangela Saraiva Oliveira 05 December 2013 (has links)
Made available in DSpace on 2015-03-26T13:32:20Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2979967 bytes, checksum: f97bfb5902403a1ee6ae3b1a64814b8b (MD5) Previous issue date: 2013-12-05 / The objective of this study was to evaluate the spatial distribution of the prevalence of hypertension and diabetes mellitus in the state of Minas Gerais, between 2002-2012. For the calculation of prevalence rates were considered the data obtained from the registry cords of the family record of the SIAB - MG DATASUS considering men and women with hypertension or diabetes, aged over 15, as well as the total population by municipality, most of 15 years, according to the IBGE 2010 census. We considered the 853 municipalities of Minas Gerais as units of spatial analysis and used the techniques of spatial data analysis area, highlighting the moving average site, the autocorrelation coefficients of global and local content Moran (LISA). Moreover, were built thematic maps of spatial distribution of local autocorrelation (Box Map) and identification of the cluster, using the space-time scan statistic. It was found that spatial autocorrelation for the prevalence of hypertension and diabetes, among the municipalities, which showed coefficients Moran (global) positive and significant for all years studied, indicating similarity between the municipalities. It was possible to identify, by analyzing local grouping of municipalities in the southern part of the state with the highest prevalence rates of hypertension and diabetes also in all years studied. Also it was found that persisted cluster in space and time for both variables and is located in the southern state. We conclude that the spatial analysis to map and understand the distribution of rates of hypertension and diabetes in the state of Minas Gerais. Studies like this provide information to the local health services can select the main places with high rates in an attempt to propose actions to control and monitor the regions with low rates. / O objetivo deste estudo foi avaliar a distribuição espacial da taxa de prevalência de hipertensão arterial e diabetes mellitus do estado de Minas Gerais, entre 2002 a 2012. Para o cálculo das taxas de prevalência, foram considerados os dados obtidos por meio dos registros do cadastro familiar do SIAB-MG do DATASUS, considerando homens e mulheres hipertensos ou diabéticos, acima de 15 anos, bem como a população total por município, maior de 15 anos, conforme censo 2010 do IBGE. Foram considerados os 853 municípios de Minas Geais como unidades de análise espacial e utilizou-se as técnicas de análise espacial de dados de área, destacando-se a média móvel local, os coeficientes de autocorrelação global de Moran e o índice local de Moran (LISA). Além disso, foram construídos mapas temáticos de distribuição espacial, de autocorrelação local (Box Map) e de identificação de cluster, utilizando a estatística Scan espaço- temporal. Verificou-se que há autocorrelação espacial para a taxa de prevalência de hipertensão e de diabetes, entre os municípios, em que apresentou coeficientes de Moran (global) positivos e significativos para todos os anos estudados, indicando similaridade entre os municípios. Foi possível identificar, por meio da análise local, agrupamento de municípios situados na parte sul do estado com maiores taxas de prevalência de hipertensão e também de diabetes em todos os anos estudados. Também constatou-se cluster que persistiram no espaço e no tempo para ambas as variáveis e que se localizaram no sul do estado. Conclui-se que a análise espacial permitiu mapear e compreender a distribuição das taxas de hipertensão e diabetes no estado de Minas Gerais. Estudos como este fornecem informações para que os serviços de saúde local possam selecionar os principais locais com taxas altas, na tentativa de propor ações de controle, bem como monitorar as regiões que apresentam taxas baixas.
148

Analyse spatiale intrasite de l'habitat : méthodologie, procédures et études de cas : les sites protohistohistoriques de Bucy-le-Long "la Foselle" 'Aisne, Néolithique ancien), et de Changis-sur-Marne "les Pétreaux" (Seine-et-Marne, Âges du Bronze et du Fer) / Intra-site spatial analysis of settlement : analysis, procedures and case studies : protohistoric sites of Bucy-le-Long "la Fosselle" (Aisne, France, the Early Neolithic) and of Changis-sur-Marne "les Pétreaux" (Seine-et-Marne, France, the Bronze Age and the Iron Age)

Lemort, Sophie 23 November 2018 (has links)
L’analyse spatiale intrasite de l’habitat ne permet pas de recourir à un modèle général d’étude, applicable à n’importe quel site archéologique. Pourtant, plusieurs d’entre eux ont des profils semblables d’implantation de l’habitat. Peut-on donc envisager de rechercher des protocoles d’analyse qui soient transposables sur des sites d’habitat couramment rencontrés ? C’est l’objet de la présente étude à partir d’une démarche exploratoire, sur deux sites d’habitat protohistoriques. Sur le site rubané de Bucy-le-Long « la Fosselle », l’analyse se concentre sur la distribution spatiale des vestiges mobiliers au sein d’unités architecturales comparables. L’analyse des données est employée pour déterminer les différents paramètres d’étude. Le potentiel informatif des unités d’habitation, établi selon des critères morphologiques et taphonomiques, est évalué et confronté au potentiel archéologique, déterminé à partir de la richesse du mobilier et des différentes catégories d’artefacts. L’analyse globale intrasite est envisagée en regroupant les mobiliers par catégorie fonctionnelle et pour mettre en évidence des assemblages significatifs de vestiges selon les habitations. Ils permettent ainsi de caractériser et sectoriser les ensembles signifiants d’activités vivrières et d’activités techniques à l’échelle du site, à partir d’un partitionnement des maisons. Le site de Changis-sur-Marne « les Pétreaux » connaît une longue occupation du Bronze final à la Tène ancienne, ce qui rend la lecture des implantations difficiles à démêler. L’analyse spatiale est tout d’abord tentée sur des groupes de structures établies lors des travaux de terrain. Puis, la répartition du mobilier est étudiée à plusieurs échelles d’observation. Cependant, il apparaît que ces premiers découpages ne reflètent pas des groupements d’établissements ruraux significatifs. Un partitionnement des structures au sein d’entités spatiales plus restreintes est alors envisagé à partir de la recherche d’agrégats, mis en évidence par l’analyse spatiale de semis de points. La dynamique d’occupation du site est de ce fait plus aisément perceptible. Les deux études de cas sont pour finir confrontées à d’autres études spatiales menées sur des sites d’habitat. Il apparaît qu’aux côtés des vestiges mobiliers très régulièrement pris pour référence dans l’analyse spatiale intrasite de l’habitat, les vestiges immobiliers trouvent toutes leurs places. / Intra-site spatial analysis of settlement does not allow use of general model applicable to any archaeological site. However some items have similar habitat settlement profiles. Can we consider looking for protocols transposable to usual settlement sites? The purpose of this study is based on an exploratory approach, on two protohistoric settlements. On the Bandkeramik site of Bucy-le-Long "la Fosselle", the analysis focuses on spatial distribution of the material remains within comparable architectural units. Data analysis is used to determine different study parameters. The informative potential of housing units, established according to morphological and taphonomic criteria, is evaluated and compared with the archaeological potential, determined from the richness of the furniture and the different categories of artifacts. The global intra-site analysis is made by grouping the furniture by functional category, to highlight significant assemblages of vestiges according to the dwellings. They allow to characterize and to segment the significant sets of food and technical activities at the site scale, based on houses partitioning. The site of Changis-sur-Marne "les Pétreaux" having suffered a long occupation from the Late bronze to the Early la Tène period, lead to a difficult reading of the settlements. During excavation spatial analysis is tried on structures groups. Then, the distribution of furniture is studied at various observation scales. However, those first divisions do not reflect groups of obvious rural settlements. A partitioning of the structures within smaller spatial entities is then engaged starting from the search for aggregates, highlighted by the space-time hot spot analysis. The dynamic of occupation of the site is thus more easily perceptible. Two case studies are finally challenged with other spatial studies about settlement sites. In addition to the material remains commonly seen as reference in the intra-site spatial analysis of settlement, archaeological structures find all their places.
149

Extension au cadre spatial de l'estimation non paramétrique par noyaux récursifs / Extension to spatial setting of kernel recursive estimation

Yahaya, Mohamed 15 December 2016 (has links)
Dans cette thèse, nous nous intéressons aux méthodes dites récursives qui permettent une mise à jour des estimations séquentielles de données spatiales ou spatio-temporelles et qui ne nécessitent pas un stockage permanent de toutes les données. Traiter et analyser des flux des données, Data Stream, de façon effective et efficace constitue un défi actif en statistique. En effet, dans beaucoup de domaines d'applications, des décisions doivent être prises à un temps donné à la réception d'une certaine quantité de données et mises à jour une fois de nouvelles données disponibles à une autre date. Nous proposons et étudions ainsi des estimateurs à noyau de la fonction de densité de probabilité et la fonction de régression de flux de données spatiales ou spatio-temporelles. Plus précisément, nous adaptons les estimateurs à noyau classiques de Parzen-Rosenblatt et Nadaraya-Watson. Pour cela, nous combinons la méthodologie sur les estimateurs récursifs de la densité et de la régression et celle d'une distribution de nature spatiale ou spatio-temporelle. Nous donnons des applications et des études numériques des estimateurs proposés. La spécificité des méthodes étudiées réside sur le fait que les estimations prennent en compte la structure de dépendance spatiale des données considérées, ce qui est loin d'être trivial. Cette thèse s'inscrit donc dans le contexte de la statistique spatiale non-paramétrique et ses applications. Elle y apporte trois contributions principales qui reposent sur l'étude des estimateurs non-paramétriques récursifs dans un cadre spatial/spatio-temporel et s'articule autour des l'estimation récursive à noyau de la densité dans un cadre spatial, l'estimation récursive à noyau de la densité dans un cadre spatio-temporel, et l'estimation récursive à noyau de la régression dans un cadre spatial. / In this thesis, we are interested in recursive methods that allow to update sequentially estimates in a context of spatial or spatial-temporal data and that do not need a permanent storage of all data. Process and analyze Data Stream, effectively and effciently is an active challenge in statistics. In fact, in many areas, decisions should be taken at a given time at the reception of a certain amount of data and updated once new data are available at another date. We propose and study kernel estimators of the probability density function and the regression function of spatial or spatial-temporal data-stream. Specifically, we adapt the classical kernel estimators of Parzen-Rosenblatt and Nadaraya-Watson. For this, we combine the methodology of recursive estimators of density and regression and that of a distribution of spatial or spatio-temporal data. We provide applications and numerical studies of the proposed estimators. The specifcity of the methods studied resides in the fact that the estimates take into account the spatial dependence structure of the relevant data, which is far from trivial. This thesis is therefore in the context of non-parametric spatial statistics and its applications. This work makes three major contributions. which are based on the study of non-parametric estimators in a recursive spatial/space-time and revolves around the recursive kernel density estimate in a spatial context, the recursive kernel density estimate in a space-time and recursive kernel regression estimate in space.
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Geografická variabilita ve funkčních znacích ptáků Evropy / Geographical variation in functional traits of European birds

Kopsová, Lenka January 2011 (has links)
Each species has specific adaptations to its environment, and since environmental parameters reveal geographic trends, it is reasonable to expect the existence of geographic trends in species characteristics as well. The aim of this study has been to evaluate the effect of environmental conditions on geographic variability of functional traits of European birds. I have analysed the effect of temperature, precipitation, productivity, altitude and habitat type (forest, open habitats, bush, settlements, wetlands) on clutch size, number of clutches per breeding season, egg size, incubation length, age of maturity, body mass, wing, tail, bill and tarsus length. I have used data from the European breeding bird atlas, so that I have calculated mean values of all the traits for quadrats 50x50 km, and then related them to environmental characteristics using OLS and GLS. Clutch size increases with temperature, whereas the number of clutches decreases with it, indicating possible trade-off between clutch size and the number of clutches, whose result is determined by the length of breeding season. Egg size decreases with temperature, possibly due to higher survival of large eggs (and consequently juveniles) in cold regions. Incubation length increases with both temperature and environmental productivity,...

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