The master's thesis deals with possibilities for using of spatial analyses for purposes of the real estate market in using geographic information system. The focus of this thesis is on the issues for the search of appropriate documents for project development in GIS and data processing. For the definition of functional spatial analyses are followed criteria of the property location, building location, transportation accessibility, availability of services, physical and geographical parameters, positive and negative effects of the environment, restrictions on use. GIS project is presented as an interactive map containing the input data and the individual spatial analyses which describe the analyzed factors or criteria affecting the real estate market. The results of analyses represent the advantage possibilities of using GIS for dealing with appropriate of practical use for the purpose of the real estate market.

This dissertation investigates the nonlinear wave propagation phenomena in nonlinear metamaterials with nonlinear chains and nonlinear resonators using analytical and spectro-spatial analyses. In the first part of the thesis, the nonlinear metamaterials are modeled as a chain of masses with multiple local resonators attached to each cell. The nonlinearity stems from the chain's stiffness in one case and the local resonator's stiffness in another. Analytical approximates solutions are obtained for each case using perturbation techniques. These results are validated through numerical simulations and the results show good agreement. To further demonstrate the nonlinear wave propagation characteristics, spectro-spatial analyses are conducted on the numerical integration data sets. The wave profiles, short-term Fourier transform spectrograms, and contour plots of 2D Fourier transform show the presence of solitary waves for both sources of nonlinearity. In addition, spectro-spatial features demonstrate the presence of significant frequency shifts at different wavelength limits. indent The second part of the thesis studies a nonlinear electromechanical metamaterial and examines how the electromechanical coupling in the local resonator affects the wave propagation. Numerical examples indicate that the system can be used for simultaneous energy harvesting and vibration attenuation without any degradation in the size of bandgaps. Spectro-spatial analyses conducted on the electromechanical metamaterial also reveal the presence of solitons and frequency shifts. The presence of solitary wave in the electromechanical metamaterial suggests a significant improvement in energy harvesting and sensing techniques. The obtained significant frequency shift is employed to design an electromechanical diode, allowing voltage to be sensed and harvested only in one direction. Design guidelines and the role of different key parameters are presented to help designers to select the type of nonlinearity and the system parameters to improve the performance of acoustic diodes. indent The last part of this thesis studies the passive self-tuning of a metastructure via a beam-sliding mass concept. The governing equations of motions of the holding structure, resonator, and sliding mass are presented and discretized into a system of ODEs using Galerkin's projection. Given that the spatial parameters of the system continuously change over time (i.e., mode shapes and frequencies), instantaneous exact mode shapes and frequencies are determined for all possible slider positions. The numerical integration is conducted by continuously updating the spatial state of the system. The obtained exact mode shapes demonstrate that the resonance frequency of the resonator stretches over a wide frequency band. This observation indicates that the resonator can attenuates vibrations at a wide frequency range. Experiments are also conducted to demonstrate the passive self-tunability of the metastructure and the findings colloborate the analytical results. / Doctor of Philosophy / Metamaterials are artificially engineered structures that can offer incredible dynamical properties, which cannot be found in conventional homogeneous structures. Consequently, the global metamaterials market is expected to display a 23.6$%$ compound annual growth rate through 2027. Some of these exciting properties include, but not limited to, negative stiffness, negative mass, negative Poisson's ratio. The unique dynamic properties show the importance of metamaterials in many engineering applications, such as vibration reduction, noise control, and waveguiding and localization. However, beyond the linear characteristics of metamaterials, nonlinear metamaterials can exhibit more interesting nonlinear wave propagation phenomena, such as solitons, cloaking, tunable bandgaps, and wave non-reciprocity. indent This research work investigates wave propagation characteristics in nonlinear locally resonant metamaterials using analytical, numerical, and signal processing techniques. The nonlinearity stems from the chain in one case and from the local resonator in another. Numerical examples show the presence of solitary waves in both types of nonlinearity and significant frequency shift in certain frequency/wavenumber regions. The obtained significant frequency shift can be utilized to design mechanical diodes, where its operation range can be increased by introducing nonlinearity in the resonator. indent For simultaneous energy harvesting and vibration attenuation, integrating the local resonator with piezoelectric energy harvesters is also investigated in this research work with the presence of both types of nonlinearities. For weak electromechanical coupling, the results demonstrate that the band structure of the system is not affected by the electromechanical coupling. Therefore, the system can also be used for energy harvesting without any degradation in the vibration attenuation performance. This observation is also validated experimentally for the linear limit. Spectro-spatial analyses also reveal the presence of solitary output voltage waves, which can enhance the energy harvesting and sensing. The obtained significant frequency shift can be utilized to design an electromechanical diode where the wave can propagate and be harvested only in one direction. Numerical examples show that the performance of the electromechanical diode can be significantly improved by including nonlinearities in the local resonator. indent Another goal of this research work is the introduction of passive self-tuning mechanism to design self-tuning metastructure. The design of such a metastructure is motivated by the need for broadband devices that can adapt to changing environment. The passive self-tuning concept is achieved by a sliding mass coupled with a resonator. Analytical and experimental results show the ability of this system to tune itself to the excitation frequency, and hence, can control vibrations over a significantly wider frequency band as compared to conventional resonators.

Current climate warming is affecting arctic regions at a faster rate than the rest of the world. This has profound effects on permafrost that underlies most of the arctic land area. Permafrost thawing can lead to the liberation of considerable amounts of greenhouse gases as well as to significant changes in the geomorphology, hydrology, and ecology of the corresponding landscapes, which may in turn act as a positive feedback to the climate system. Vast areas of the east Siberian lowlands, which are underlain by permafrost of the Yedoma-type Ice Complex, are particularly sensitive to climate warming because of the high ice content of these permafrost deposits. Thermokarst and thermal erosion are two major types of permafrost degradation in periglacial landscapes. The associated landforms are prominent indicators of climate-induced environmental variations on the regional scale. Thermokarst lakes and basins (alasses) as well as thermo-erosional valleys are widely distributed in the coastal lowlands adjacent to the Laptev Sea. This thesis investigates the spatial distribution and morphometric properties of these degradational features to reconstruct their evolutionary conditions during the Holocene and to deduce information on the potential impact of future permafrost degradation under the projected climate warming. The methodological approach is a combination of remote sensing, geoinformation, and field investigations, which integrates analyses on local to regional spatial scales. Thermokarst and thermal erosion have affected the study region to a great extent. In the Ice Complex area of the Lena River Delta, thermokarst basins cover a much larger area than do present thermokarst lakes on Yedoma uplands (20.0 and 2.2 %, respectively), which indicates that the conditions for large-area thermokarst development were more suitable in the past. This is supported by the reconstruction of the development of an individual alas in the Lena River Delta, which reveals a prolonged phase of high thermokarst activity since the Pleistocene/Holocene transition that created a large and deep basin. After the drainage of the primary thermokarst lake during the mid-Holocene, permafrost aggradation and degradation have occurred in parallel and in shorter alternating stages within the alas, resulting in a complex thermokarst landscape. Though more dynamic than during the first phase, late Holocene thermokarst activity in the alas was not capable of degrading large portions of Pleistocene Ice Complex deposits and substantially altering the Yedoma relief. Further thermokarst development in existing alasses is restricted to thin layers of Holocene ice-rich alas sediments, because the Ice Complex deposits underneath the large primary thermokarst lakes have thawed completely and the underlying deposits are ice-poor fluvial sands. Thermokarst processes on undisturbed Yedoma uplands have the highest impact on the alteration of Ice Complex deposits, but will be limited to smaller areal extents in the future because of the reduced availability of large undisturbed upland surfaces with poor drainage. On Kurungnakh Island in the central Lena River Delta, the area of Yedoma uplands available for future thermokarst development amounts to only 33.7 %. The increasing proximity of newly developing thermokarst lakes on Yedoma uplands to existing degradational features and other topographic lows decreases the possibility for thermokarst lakes to reach large sizes before drainage occurs. Drainage of thermokarst lakes due to thermal erosion is common in the study region, but thermo-erosional valleys also provide water to thermokarst lakes and alasses. Besides these direct hydrological interactions between thermokarst and thermal erosion on the local scale, an interdependence between both processes exists on the regional scale. A regional analysis of extensive networks of thermo-erosional valleys in three lowland regions of the Laptev Sea with a total study area of 5,800 km² found that these features are more common in areas with higher slopes and relief gradients, whereas thermokarst development is more pronounced in flat lowlands with lower relief gradients. The combined results of this thesis highlight the need for comprehensive analyses of both, thermokarst and thermal erosion, in order to assess past and future impacts and feedbacks of the degradation of ice-rich permafrost on hydrology and climate of a certain region. / Die gegenwärtige Klimaerwärmung wirkt sich auf arktische Regionen stärker aus als auf andere Gebiete der Erde. Das hat weitreichende Konsequenzen für Permafrost, der weite Teile der terrestrischen Arktis unterlagert. Das Tauen von Permafrost kann zur Freisetzung erheblicher Mengen an Treibhausgasen sowie zu gravierenden Änderungen in der Geomorphologie, Hydrologie und Ökologie betroffener Landschaften führen, was wiederum als positive Rückkopplung auf das Klimasystem wirken kann. Ausgedehnte Gebiete der ostsibirischen Tiefländer, die mit Permafrost des Yedoma Eiskomplex unterlagert sind, gelten aufgrund des hohen Eisgehalts dieser Permafrostablagerungen als besonders empfindlich gegenüber Klimaerwärmungen. Thermokarst und Thermoerosion sind zwei Hauptformen der Permafrostdegradation in periglazialen Landschaften. Die zugehörigen Landschaftsformen sind auf der regionalen Skala bedeutende Indikatoren klimainduzierter Umweltvariationen. Thermokarstseen und senken (Alasse) sowie Thermoerosionstäler sind in den Küstentiefländern der Laptewsee weit verbreitet. Die vorliegende Dissertation untersucht die räumliche Verbreitung und die morphometrischen Eigenschaften dieser Degradationsformen mit dem Ziel, ihre Entwicklungsbedingungen während des Holozäns zu rekonstruieren und Hinweise auf potenzielle Auswirkungen zukünftiger Permafrostdegradation im Zuge der erwarteten Klimaerwärmung abzuleiten. Der methodische Ansatz ist eine Kombination aus Fernerkundungs-, Geoinformations- und Geländeuntersuchungen, die Analysen auf lokalen bis regionalen räumlichen Skalen integriert. Thermokarst und Thermoerosion haben die Untersuchungsregion tiefgreifend geprägt. Im Eiskomplexgebiet des Lena-Deltas nehmen Thermokarstsenken eine weitaus größere Fläche ein als Thermokarstseen auf Yedoma-Hochflächen (20,0 bzw. 2,2 %), was darauf hin deutet, dass die Bedingungen für die Entwicklung von großflächigem Thermokarst in der Vergangenheit wesentlich günstiger waren als heute. Die Rekonstruktion der Entwicklung eines einzelnen Alas im Lena-Delta belegt eine andauernde Phase hoher Thermokarstaktivität seit dem Übergang vom Pleistozän zum Holozän, die zur Entstehung einer großen und tiefen Senke führte. Nach der Drainage des primären Thermokarstsees im mittleren Holozän erfolgten Permafrostaggradation und degradation parallel und in kürzeren abwechselnden Etappen innerhalb des Alas und führten zu einer komplexen Thermokarstlandschaft. Trotzdem die spätholozäne Thermokarstentwicklung im Alas dynamischer ablief als die erste Entwicklungsphase, resultierte sie nicht in der Degradation großer Teile pleistozäner Eiskomplexablagerungen und einer wesentlichen Veränderung des Yedoma-Reliefs. Weitere Thermokarstentwicklung in bestehenden Alassen ist begrenzt auf geringmächtige Lagen holozäner eisreicher Alas-Sedimente, da die Eiskomplexablagerungen unter den großen primären Thermokarstseen vollständig getaut waren und die unterlagernden Sedimente aus eisarmen, fluvialen Sanden bestehen. Thermokarstprozesse auf ungestörten Yedoma-Hochflächen wirken am stärksten verändernd auf Eiskomplexablagerungen, werden aber in Zukunft auf geringere Ausmaße begrenzt sein, da die Verfügbarkeit großer ungestörter, schwach drainierter Yedoma-Hochflächen abnimmt. Auf der Insel Kurungnakh im zentralen Lena-Delta beträgt der für zukünftige Thermokarstentwicklung verfügbare Anteil an Yedoma-Hochflächen nur 33,7 %. Die zunehmende Nähe von sich entwickelnden Thermokarstseen auf Yedoma-Hochflächen zu bestehenden Degradationsstrukturen und anderen negativen Reliefformen verringert die Möglichkeit der Thermokarstseen, große Ausmaße zu erreichen bevor sie drainieren. Die Drainage von Thermokarstseen durch Thermoerosion ist in der Untersuchungsregion weit verbreitet, aber Thermoerosionstäler versorgen Thermokarstseen und –senken auch mit Wasser. Neben diesen direkten hydrologischen Wechselwirkungen zwischen Thermokarst und Thermoerosion auf der lokalen Ebene existiert auch eine Interdependenz zwischen beiden Prozessen auf der regionalen Ebene. Eine regionale Analyse weitreichender Netze von Thermoerosionstälern in drei Tieflandgebieten der Laptewsee mit einer Fläche von insgesamt 5800 km² zeigte, dass diese Formen häufiger in Gebieten mit höheren Geländeneigungen und Reliefgradienten auftreten, während Thermokarstentwicklung stärker in flachen Tiefländern mit geringeren Reliefgradienten ausgeprägt ist. Die kombinierten Ergebnisse dieser Dissertation zeigen die Notwendigkeit von umfassenden Analysen beider Prozesse und Landschaftsformen, Thermokarst und Thermoerosion, im Hinblick auf die Abschätzung vergangener und zukünftiger Auswirkungen der Degradation eisreichen Permafrosts auf Hydrologie und Klima der betrachteten Region und deren Rückkopplungen.

Made available in DSpace on 2015-05-14T12:47:10Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 861286 bytes, checksum: bad07c7c42be04f830fe6e9d88b422ba (MD5) Previous issue date: 2011-02-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / There is concern about the conditions of food and nutritional security of Brazilian population. In Brazil, according to Law no. 11,346 in 2006, featuring the food and nutrition security as a multidimensional process, being determined by factors ranging from agricultural production, food distribution and access to population, economic access to food, even the food choice, based on cultural components. Many instruments are used to determine the food security situation, and these instruments do not allow an evaluation of the data at the municipal level, which difficulties the decision to qualify each cities. Thus, this study presents a methodology that considers various factors related to a situation of uncertainty through the application of fuzzy logic, and therefore the purpose of analyzing the food security situation of cities of Paraíba through the application of fuzzy logic, describing factors associated with this situation in order to help decision making and prioritizing interventions, supporting the process of planning programs and rules. In epidemiology situations lead the researcher to complex issues, imprecise and uncertain, and fuzzy sets theory is applied in such cases by its ability to deal with such situations of uncertainty. Besides the application of the decision model of fuzzy logic, we performed a spatial analysis, where the 221 cities were identified, according to the food security situation. The results therefore show that 48% of this cities are in the food security situation of risk, followed by 33.5%, which are in an acceptable, and 18.5% in unacceptable conditions. These data draw attention to the characterization of the situation in Paraíba, with 106 municipalities at risk and 41 in unacceptable conditions, which are the municipalities as priorities for intervention. It is evident therefore that the methodology adopted is to be an important tool to define the trends priority intervention in the municipality in order to allow identification of the food security situation in this sphere of government and may support the decision making and planning actions aimed for promotion food security. / Observa-se a preocupação com as condições de segurança alimentar e nutricional da população brasileira. O conceito adotado pelo Brasil, conforme a Lei nº. 11.346 de 2006, caracteriza a segurança alimentar e nutricional como um processo multidimensional, sendo determinado por fatores que vão desde a produção agrícola, distribuição e acesso dos alimentos à população, acesso econômico ao alimento, até a própria escolha alimentar, baseada em componentes culturais. Vários instrumentos são utilizados em estudos para a determinação da situação de segurança alimentar, sendo que esses instrumentos não permitem uma avaliação dos dados ao nível municipal, prejudicando a ação de políticas públicas prioritárias e específicas de cada município. Dessa forma, este estudo apresenta uma metodologia que considera diferentes fatores relacionados a uma situação de incerteza através da aplicação da lógica fuzzy, tendo, pois, o objetivo de analisar a situação de segurança alimentar de municípios da Paraíba através da aplicação da lógica fuzzy, descrevendo os fatores associados a esta situação, com a finalidade favorecer a tomada de decisão e priorizar a intervenção, subsidiando o processo de planejamento de programas e políticas públicas. Na área da Epidemiologia situações levam o pesquisador a questões complexas, imprecisas e de incerteza, e a teoria de conjuntos fuzzy nesses casos é aplicada pela sua capacidade de lidar com tais situações de incerteza. Além da aplicação do modelo de decisão da lógica fuzzy, foi realizada a análise espacial, onde os 221 municípios foram identificados, segundo a situação de segurança alimentar. Os resultados, portanto, mostram que 48% dos municípios da Paraíba estão em situação de segurança alimentar de risco, seguidos de 33,5%, que estão em situação aceitável, e, 18,5%, em situação inaceitável. Esses dados chamam a atenção para a caracterização da situação na Paraíba, estando 106 municípios em situação de risco e 41 em situação inaceitável, sendo estes os municípios prioritários para intervenção. Evidencia-se, pois, que a metodologia adotada constitui-se um instrumento importante para definir as tendências prioritárias de intervenção no município, no sentido de permitir a identificação da situação de segurança alimentar nessa esfera de governo, podendo subsidiar a tomada de decisão e o planejamento de ações que visem a promoção da segurança alimentar.

Made available in DSpace on 2016-12-23T14:37:38Z (GMT). No. of bitstreams: 1 Jose Marcilio da Silva.pdf: 1307724 bytes, checksum: d09f0919618708be274d4001c04c2597 (MD5) Previous issue date: 2006-11-01 / Nowadays soybean culture occupies great area in Brazilian savannah region. And this commodity has a great commercial importance for economy of Brazil as source of richness. Geostatistics, which allows detecting existence of variability and spatial distribution, constituting an important tool for analysis and detail description of soil attributes. This work was carries out with objective to evaluate spatial variability of chemical and physical attributes of soils cultivated with soybean, under no-tillage (PD) and conventional-tillage (PC) systems. Data analysis was realized by means of classic statistics and geostatistics. Data were collected in Rio Verde Goiás State, at Fazenda Monte Alegre, where two sample areas were referenced by means of Global Positioning System (GPS), and established a fishnet with 44 points, with dimension of 40 x 55 m. It was studied in these areas the following attributes: (a) in the depths of 0 to 10 cm, 10 to 20 cm and 20 to 40 cm - soil density (Ds), microporosity (MiP), macroporosity (MaP), total porosity of the soil (Pt); (b) in the depths of 0 to 20 cm and 20 to 40 cm - mechanical resistance attributes of the soil to the penetration (RP) and soil moisture (U); and (c) in the depths 0 to 5 cm and 5 to 15 cm the following chemical attributes: the activity of hydrogen ions (pH in CaCl2), organic matter (MO), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), aluminum (Al), potential acidity (H+Al), sum of bases (SB), cation exchange capacity (CTC) and exchangeable base saturation (V). It was accomplished descriptive statistical analysis of the attributes, followed of a geostatistical analysis based in the presuppositions of stationary of the intrinsic hypothesis, from semivariograma analyses. After adjustments of theoretical models, it was applied kriging method to estimate no-sampled values in the field, by building thematic maps that shows spatial distribution for attributes. Eighty two and seventy three percent of chemical attributes showed normal distribution for PC and PD, respectively. All evaluated physical attributes in the three first depths presented normal distribution, while for the others two it was not observed the same behavior. In the depth 0 to 5 cm, the chemical attributes MO and H+Al did not show significant difference between cultivation systems, the same happened with Mg and CTC in the depth 5 to 15 cm. For the same cultivation system compared in these two depths, P, Mg and Al in PC and Ca in PD did not show significant difference. Most of the studied chemical attributes in PC and PD reveal spatial dependence between moderate and strong, except K that presents low spatial dependence in PC in the depth from 0 to 5 cm. All physical attributes demonstrated significant difference, with exception for Ds and Pt in the depth from 20 to 40 cm. Most of the evaluated physical attributes in PC show spatial dependence between moderate and strong, except MaP in the depth from 0 to 10 cm, Ds and MiP from 10 to 20 cm, MiP and MaP from 20 to 40 cm, and RP in the two considered depths. In PD attributes MiP in the three depths, Pt from 10 to 20 cm, Ds and MaP and U in the depth from 20 to 40 cm do not present spatial dependence. The use of the assigned semivariograms allowed verifying the same pattern of spatial dependence for chemical attributes pH, MO, Al, H+Al and CTC, and physical Ds and Pt in PC and in PD for RP. The soil management practice in PC area was decisive to increase soybean productivity in relation PD area. The use of the Geographic Information System (GIS), associate with geostatistical methods, supports decisions at soil management practice, this increases practical potential uses of these methods / A cultura da soja ocupa grandes extensões de área plantada na região do cerrado brasileiro e, é considerada um commodities de grande importância comercial para a economia do Brasil como fonte geradora de riqueza. A análise geoestatística permite detectar a existência da variabilidade e distribuição espacial, constituindo importante ferramenta na análise e descrição detalhada dos atributos do solo. O presente trabalho teve como objetivo avaliar a variabilidade espacial de atributos químicos e físicos do solo no cultivo de soja sob plantio direto (PD) e preparo convencional do solo (PC), em área de cerrado, usando a técnica da estatística clássica e da geoestatística na análise dos dados. Os dados foram coletados em duas áreas na Fazenda Monte Alegre, no município de Rio Verde Goiás, em pontos de amostragem georeferenciadas com auxílio de um sistema de posicionamento global (GPS), definidos segundo uma malha regular com 44 pontos, com dimensão de 40 x 55 m. Foram estudados no PD e PC nas profundidades 0 a 10 cm, 10 a 20 cm e 20 a 40 cm os seguintes atributos físicos: densidade do solo (Ds), microporosidade (MiP), macroporosidade (MaP), porosidade total do solo (Pt), e nas profundidades 0 a 20 cm e 20 a 40 cm os atributos resistência mecânica do solo à penetração (RP) e umidade do solo (U); e os seguintes atributos químicos nas profundidades 0 a 5 cm e 5 a 15 cm: potencial hidrogeniônico (pH em CaCl2), matéria orgânica (MO), fósforo (P), potássio (K), cálcio (Ca), magnésio (Mg), alumínio (Al), acidez potencial (H+Al), soma de bases (SB), capacidade de troca de cátions (CTC) e saturação por bases trocáveis (V). Foi realizada análise descritiva dos atributos, seguida da análise geoestatística com base nas pressuposições de estacionaridade da hipótese intrínseca pela análise a partir de semivariogramas. Após ajustes dos modelos teóricos, realizou-se a interpolação por krigagem para estimar valores não amostrados no campo, construindo os mapas temáticos de contornos para os atributos que apresentaram distribuição espacial. Oitenta e dois e setenta e três porcento dos atributos químicos apresentam distribuição normal para PD e PC, respectivamente. Os atributos físicos avaliados nas três primeiras profundidades apresentam cem porcento de distribuição normal, enquanto que nas outras duas não apresentam o mesmo comportamento. Na profundidade 0 a 5 cm, os atributos químicos MO e H+Al não apresentam diferença significativa entre os manejos, o mesmo ocorrendo com o Mg e a CTC na profundidade de 5 a 15 cm. Para o mesmo manejo comparado nas duas profundidades, o P, o Mg e o Al no PC e o Ca no PD não apresentam diferença significativa. A maioria dos atributos químicos avaliados no PC e PD apresenta dependência espacial entre moderada e forte, exceto o K que apresenta baixa dependência espacial no PC na profundidade de 0 a 5 cm. Todos os atributos físicos apresentam diferença significativa, com exceção para Ds e Pt na profundidade de 20 a 40 cm. A maioria dos atributos físicos avaliados no PC do solo apresenta dependência espacial entre moderada e forte, exceto a MaP na profundidade de 0 a 10 cm, Ds e MiP de 10 a 20 cm, MiP e MaP de 20 a 40 cm, e RP nas duas profundidades avaliadas. No PD, os atributos MiP nas três profundidades, a Pt de 10 a 20 cm, Ds e MaP e U na profundidade de 20 a 40 cm apresentam ausência de dependência espacial. O uso do semivariograma escalonado permite verificar o mesmo padrão de dependência espacial para os atributos químicos pH, MO, Al, H+Al e CTC, e físicos Ds e Pt no PC e no PD para RP. O manejo na área sob PC é decisivo no aumento da produtividade da soja em relação à área sob PD. O uso do sistema de informação geográfica associado a métodos geoestatísticos contribui com a tomada de decisão na implementação do manejo do solo, aumentando o potencial de utilização prática desses métodos

The decrease of semi-natural grasslands in Europe during the last decade has made several previously common species rare or declining in numbers. One of these species is the endangered field gentian Gentianella campestris, which has been proposed as an important indicator species for semi-natural grasslands. Previous studies have highlighted the importance of consistent management and shown how local conditions affect the species. Less is known about how the population is affected by isolation and changes in the surrounding landscape, both of which are potential consequences of habitat loss.This study utilized long term citizen science data on the population changes to explore if local and regional factors, such as connectivity could explain the rapid decline and local extinctions that the field gentian population in Östergötland, Sweden, has experienced since the beginning of the 1990’s. Generalized linear models showed that the declining field gentian population can partly be explained by changes in the surrounding landscape which has led to decreased connectivity of semi-natural grasslands. The study also indicate that there is a need for future management plans to consider the surrounding landscape on a distance of 1-3 km from field gentian localities as this scale seems to be the most important.

The strong emphasis placed on improving equality and well-being for all in the Sustainable Development Goals underscores the importance of tackling persistent within-country disparities in maternal mortality and poor health outcomes. Addressing maternal healthcare access barriers is, thus, crucial, particularly in low-resource settings. Numerous studies investigating determinants of maternal healthcare service use in Ethiopia exist but are limited by their focus on individual and household factors, and by methodological weaknesses. A nuanced understanding of the role of socioeconomic and geographic context in influencing access to care is needed to respond effectively. Maternity waiting homes (MWHs) are a potential strategy to address geographical barriers that delay women’s access to obstetric care. However, in addition to concerns about service quality, there is limited evidence on their effectiveness and on what models meet women’s needs. My research goals were, therefore, to contribute to the understanding of what contextual factors influence maternal healthcare service use in general; and to determine whether or not upgraded MWHs operating in an enabling environment could improve delivery care use in rural Ethiopia. My primary data sources were household surveys conducted as part of a cluster-randomized controlled trial evaluating MWHs and local leader training in Jimma Zone, Ethiopia. Random effects multivariable logistic regression analysis of survey data brought to light the social and financial resources that facilitate MWH use, highlighting the need for complementary interventions to make access more equitable. Spatial analyses identified subnational variation in service use at a finer scale than routinely reported and unmasked local variation in the relevance and magnitude of associations between individual-, interpersonal-, and health system factors and maternal healthcare use. These findings have implications for relying upon homogenous national responses to improve equality in access to care and health outcomes. Finally, analysis of trial data found a non-significant effect of interventions on delivery care use likely due to implementation issues and extraneous factors. The need to generate strong evidence of effectiveness of MWHs in improving maternal healthcare service use using sustainable and equitable MWH models using methods appropriate for complex intervention evaluation remains.

La compréhension des processus écologiques qui sous-tendent l’assemblage des communautés végétales et la coexistence des espèces est un objectif central en écologie. Ces processus sont potentiellement nombreux et de natures contrastées. Ainsi, la composition d’une communauté de plantes dépend de processus déterministes liés aux conditions environnementales abiotiques (climat, conditions physiques et chimiques du sol, lumière) et d’interactions biotiques complexes, positives (facilitation, symbioses) comme négatives (compétition, prédation, pathogènes). En outre, les communautés sont influencées par des processus stochastiques (capacité de dispersion limitée, dérive écologique). Si les mécanismes à l’origine de ces processus sont très différents, ils ont néanmoins en commun la génération de motifs (patterns) spatiaux de distribution d’espèces dans les communautés. L’analyse de la structure spatiale des communautés permet ainsi une étude indirecte des processus régissant les communautés. La nature complexe de ces patterns spatiaux a mené au développement de nombreuses méthodes statistiques de détection et de description de patterns. Les méthodes basées sur des vecteurs propres spatiaux sont parmi les plus puissantes et précises pour détecter des patterns complexes et multi-échelles. Ces vecteurs propres, utilisés comme prédicteurs spatiaux, peuvent être combinés à un ensemble de variables environnementales dans un cadre de partition de variation. Celui-ci permet, en théorie, de démêler les effets uniques et l’effet conjoint des variables environnementales et spatiales sur la variation de composition d’une communauté. Il mène ainsi à une quantification de l’action des processus déterministes et des processus stochastiques sur l’assemblage de la communauté. Néanmoins, je montre dans cette thèse qu’un certain flou méthodologique concernant deux étapes déterminantes des analyses basées sur les vecteurs propres spatiaux a mené une proportion élevée d’études à utiliser ces méthodes de manière sous-optimale, voire fortement biaisée. Ceci compromet la fiabilité des patterns spatiaux détectés et des processus écologiques inférés. Une autre limitation de ce cadre d’analyse concerne la fraction de la partition de variation décrivant l’effet environnemental spatialement structurés qu’aucune méthode ne permet de tester.Cette thèse présente des solutions non biaisées, puissantes et précises à ces différentes limitations méthodologiques et permet d’élargir le cadre de l’inférence de processus écologique à partir de patterns spatiaux de communautés. Les différentes étapes d’amélioration de ces méthodes ont également été illustrées dans la thèse au travers de trois cas d’études fournis par deux communautés d’arbres tropicale et tempérée et une communauté de champignons symbiotiques des arbres. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

L’objectif de la thèse était de développer un indicateur mesurant l’accessibilité spatiale des premiers soins (nommé Index of Spatial Accessibility : ISA) pour les femmes enceintes, à partir de sources de données collectant des informations en routine. Ce travail a pour vocation de mettre en évidence les limites des indicateurs existants tout en apportant des améliorations. Une attention particulière a consisté à étudier l’impact de l’effet des contours administratifs (ou effet de bord), la limite pointée dans de nombreuses études portant sur l’accès aux soins. L’indicateur d’accessibilité aux professionnels de santé que nous avons développé a pour objectif de mettre en évidence les disparités spatiales à une échelle géographique fine afin d’identifier les zones géographiques dans lesquelles il faudrait intervenir en priorité. Ce travail s’est concentré tout d’abord sur les professionnels de santé intervenant dans le suivi de la grossesse : médecins généralistes, sages-femmes et gynécologues. Les résultats mettent en évidence qu’en combinant la disponibilité avec la proximité des soins, les besoins en matière de santé et la mobilité, l’ISA permet de fournir une meilleure mesure d’accessibilité. L’ISA a été construit afin de pouvoir interroger l’accès aux soins pour d’autres pathologies ou d’autres populations. L’analyse de l’impact de l’effet de bord met en évidence que : 1) la moyenne et l'écart-type sont légèrement inférieurs avec effet de bord que sans, quel que soit le type des professionnels de santé ; 2) La variation d’ISA est plus marquée pour les sages-femmes et les gynécologues, et pour les zones rurales. Nous avons également menée une étude pilote sur le recours aux soins des femmes enceinte, à partir des données SNIIRAM afin d’étudier la relation entre le recours aux soins et l’indicateur ISA. / This paper developed an improved indicator: the Index of Spatial Accessibility (ISA) to measure geographical healthcare accessibility at the census blocks level, and seeks to assess the effect of edge on the accuracy of defining healthcare provider access by comparing healthcare provider accessibility accounting or not for the edge effect, in a real-world application. The indicator of accessibility to health professionals developed aims to highlight spatial disparities measured at a fine geographical scale and to identify area where actions are needed in priority. This work focused first of all on the health professionals involved in the follow-up of the pregnancy: general practitioners, midwives and gynecologists. The main finding is that by combining availability with proximity to services, health needs and mobility, and by calculating at the smallest feasible geographical scale, ISA provides a better measure of accessibility. ISA was conceived so that we could question the access to care for other pathologies and other populations. When we compare the variation of ISA with and without edge effect, we found that (1) mean and standard deviation are slightly below when offer and demand outside are taken in to account, whichever health professionals considered; 2) the variation of ISA is higher for midwives and gynecologists, and for rural areas. In addition, we also conducted a pilot study on the health use of pregnant women, using SNIIRAM data to examine the relationship between use of care and the ISA indicator.

The aim of this thesis is to visualize and explain how people’s economic and social relations were connected in the parish of Sundborn, in the south east of Dalarna, in the period 1820-1849. The study is based on records of claims and debts in inventories and parish registers, which enable reconstruction of the private local credit market. The study shows that the majority in the economic network lived in Sundborn, and that while few people had formal loans at the institutional credit market, many had loans by trust at the private local credit market. Also, while few people were lenders, almost everyone was a borrower. The most common credit relationship was between people who lived near one another, and people who lived near one another or were related received a higher average credit. The private local credit market consisted primarily of men. These results have been interpreted with the use of social network theory, it being shown that people depended on their social network to obtain the necessary credit. In creating an economic network graph, I show that households in the parish of Sundborn were interconnected by debt relations. By using this method, it is possible to identify significant persons and potential parish bankers. Through combining the network graph with a landscape map, I show connections between the settlement, the assets, economic relations, centrality and the long valley of Sundborn river. The study opens up possibilities for further development of the same method to visualize historic data and relate it to the landscape, with a view to generating new related questions and spatial analyses.