Dissertations / Theses on the topic 'Attributs temporels'

Possession is an asymmetric semantic relation between two entities, where one entity (the possessee) belongs to the other entity (the possessor). Automatically extracting possessions are useful in identifying skills, recommender systems and in natural language understanding. Possessions can be found in different communication modalities including text, images, videos, and audios. In this dissertation, I elaborate on the techniques I used to extract possessions. I begin with extracting possessions at the sentence level including the type and temporal anchors. Then, I extract the duration of possession and co-possessions (if multiple possessors possess the same entity). Next, I extract possessions from an entire Wikipedia article capturing the change of possessors over time. I extract possessions from social media including both text and images. Finally, I also present dense annotations generating possession timelines. I present separate datasets, detailed corpus analysis, and machine learning models for each task described above.

Aujourd’hui, l’air est pollué par de nombreuses substances chimiques, difficile à identifier. Plusieurs gaz marqueurs sont caractéristiques de la pollution, comme le monoxyde de carbone (CO), l'ozone (O3) et le dioxyde d'azote (NO2). Les capteurs de gaz à base d’oxyde métallique (MOX) sont des bons candidats pour suivre en temps réel la qualité de l’air. Ils sont largement utilisés dans les dispositifs de détection de gaz portables et à faible coût. Très sensibles, stables et avec une grande durée de vie, les capteurs MOX souffrent d'un manque inhérent de sélectivité, qui peut être comblé en y intégrant de l’intelligence artificielle. Ce travail de thèse s’intéresse à la mise en œuvre de méthodes d’identification de gaz basées sur l’analyse de données expérimentales. L’objectif est de discriminer le CO, l’O3, et le NO2, avec un seul capteur, dans des conditions réelles d’utilisation (faible débit, humidité...). Pour cela, nous utilisons un capteur de gaz à base d’oxyde de tungstène (WO3) breveté par l’IM2NP et exploité sous licence mondiale par la société NANOZ. Une base de données expérimentale complète a été créée à partir d’un protocole basé sur la modulation de la température de la couche sensible. À partir de cette base de données nous avons mis en œuvre deux méthodes différentes d’extractions de paramètres : le calcul des attributs temporels et la transformée en ondelettes. Ces deux méthodes ont été évaluées sur leur capacité de discrimination des gaz grâce à l’utilisation de plusieurs familles d’algorithmes de classification tels que les machines à vecteurs de support (SVM), les K plus proches voisins (KNN), les réseaux de neurone
Today the air is polluted by many chemicals, which are in the form of a complex mixture that is difficult to identify. These marker gases include carbon monoxide (CO), ozone (O3) and nitrogen dioxide (NO2). It has therefore become imperative to design detection systems that are inexpensive, but at the same time highly sensitive and selective, in order to monitor air quality in real time. Metal Oxide gas sensors (MOX) can meet these requirements. They are used in portable and low cost gas detection devices. Very sensitive, stable and with a long lifespan, MOX sensors suffer from an inherent lack of selectivity, which can be overcome by integrating artificial intelligence. This thesis is concerned with the implementation of gas identification methods based on the analysis of experimental data. The objective is to discriminate three pollution marker gases: CO, O3, and NO2, with a single sensor, under real conditions of use, i.e. in the permanent presence of a concentration of these gases in the humid ambient air. For this, we use a tungsten oxide (WO3) gas sensor patented by IM2NP laboratory and operated under a worldwide license by the company NANOZ.A complete experimental database was created from a protocol based on temperature modulation of the sensitive layer. From this database, we implemented two different feature extraction methods: the computation of temporal attributes and the wavelet transform. These two methods were evaluated on their gas discrimination capacity thanks to the use of several families of classification algorithms, such as support vector machines (SVM), decision trees, K nearest neighbours, neural networks, etc

Grave markers reflect a wealth of information and collectively epitomize society's historic, social, and economic patterns over time. Despite an abundance of cemetery research in other parts of the country, little research has been undertaken to evaluate grave marker attributes in Florida. The purpose of this research was to determine how grave marker attributes have changed over time in north-central, central, and southeast Florida. Data were collected from ten cemeteries in five counties in Florida, representing the grave markers of over 1,100 individuals. Data collection involved visiting each cemetery, photographing markers, and cataloging grave marker attributes. Attributes analyzed included marker type, marker material, epitaphs, iconographic images, memorial photographs, footstones, and kerbs. A number of important trends were noted. Marker material exhibited the clearest example of a temporal trend, shifting over time from 73% marble to 73% granite. Marker type varied greatly from upright and flat ground markers to a variety of customized markers and vaults. Cultural differences were also noted with in-ground vaults dominating traditionally black cemeteries. There were clear differences in marker style between affluent and less affluent cemeteries, with numerous hand-cast cement markers observed in less prosperous areas. Furthermore, beginning in the early 1980's there is an increase in customized laser engraved markers. Overall, Florida's cemeteries offer a rich history of the state's mortuary practices and further research should be conducted to preserve this history.
B.S.
Bachelors
Sciences
Anthropology

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A Antártica Marítima apresenta alta sensibilidade às mudanças climáticas, especialmente pelas alterações na temperatura do ar, que modificam a dinâmica do carbono e atributos do solo nos ecossistemas terrestres. Sendo assim, variáveis relacionadas ao solo (ou seja, carbono orgânico, temperatura do solo e umidade do solo), e o padrão de distribuição da vegetação, podem ser indicadores das mudanças climáticas. O objetivo deste trabalho foi investigar a relação espacial e temporal entre as trocas de carbono, o status de nutrientes do solo e seu desenvolvimento nos principais ecossistemas terrestres da Antártica Marítima. O estudo foi realizado na Península Keller e Coppermine, Ilha Rei George e Robert, respectivamente. Grids regulares foram instalados para avaliar a variabilidade espacial de atributos gerais do solo e troca de carbono em campos de liquens, musgos, liquens/musgos e locais de solo exposto, ao longo das áreas livres de gelo. Usando técnicas de geoestatística, a dependência espacial foi acessada através da modelagem do semivariograma e dimensão fractal. Amostras de solo foram coletadas em diferentes camadas para determinar alguns atributos gerais do solo. A respiração total do ecossistema, troca líquida do ecossistema e produção primária bruta foram determinadas medindo fluxos de CO 2 in situ, com um sistema automático de fechamento da câmara de medição (LI-COR Biosciences, Lincoln, NE, EUA), baseado em medições de curto e longo prazo. Os resultados indicam uma alta capacidade dos tapetes de musgos (principalmente por Sanionia uncinata), para atuar como dreno de carbono, em locais onde a umidade do solo é elevada. Por outro lado, onde o guano é depositado, a temperatura do solo é elevada, levando a um aumento da mineralização da matéria orgânica, respiração do ecossistema, atuando como fonte de carbono para a atmosfera. A dependência espacial variou entre os locais, sendo que a deposição do guano e a cobertura vegetal governam a extensão da estrutura espacial. Os valores de dimensão fractal mostraram que há uma forte relação espacial entre o carbono orgânico e o alumínio. Os solos são caracterizados principalmente pelas altas quantidades de bases e incipiente formação de argila. Em zonas com influência ornitogênica fraca, o solo é ácido e os valores de alumínio trocável são elevados, associados a uma acidez potencial elevada. A proximidade do permafrost está reduzindo a temperatura do solo, e consequentemente o número de dias de degelo. No entanto, sob o aquecimento atual, este local tende a agir progressivamente como uma fonte de CO 2 para a atmosfera. Por outro lado, mais turfeiras podem ser formadas devido derretimento de neve/gelo, armazenamento grandes quantidades de carbono. O balanço entre o ganho e perda de CO 2 precisa ser mais pesquisado na Antártica Marítima, a fim de elucidar a dinâmica atual considerando outras áreas livres de gelo.
Maritime Antarctica presents high sensitivity to climate change, especially by the alterations in air temperature, which modifies carbon dynamics and soil attributes in terrestrial ecosystems. Thus, variables related to soil (i.e. organic carbon, soil temperature and soil moisture), and vegetation distribution patterns, can represent climate change indicators. The objective of this work was to investigate the spatial and temporal relationship among carbon exchange, soil nutrient status and development in the main terrestrial ecosystems of Maritime Antarctica. The study was carried out at Keller and Coppermine Peninsula, in King George Island and Robert Island, respectively. Regular grids were installed to evaluate the spatial variability of general soil attributes and carbon exchange in lichens, mosses, lichens/mosses and bare soil sites along the ice- free areas. By using geostatistical techniques, spatial dependence was accessed through semivariogram and fractal dimension modeling. Soil was sampled at different soil layers to determine general soil attributes. Ecosystem respiration, net ecosystem exchange and gross primary production were determined by measuring CO 2 fluxes in situ with a closed automatic chamber system (LI-COR Biosciences, Lincoln, NE, USA), based on short and long-term measurements. Results indicate a high capacity of mosses carpets (especially by Sanionia uncinata) to act as a sink of carbon, where soil moisture is elevated. On the other hand, where guano is deposited, soil temperature is enhanced, leading to increase soil organic matter mineralization, ecosystem respiration, acting as a source of carbon to the atmosphere. Spatial dependence strongly varied among sites, where guano deposition and vegetation coverage are reported to drive the extension of spatial structure. Fractal dimension values showed great spatial relationship between organic carbon and aluminum. Soils are mainly characterized by the high amounts of bases and weak clay formation. In zones with weak ornithogenic influence, soil is acid and values of exchangeable aluminum are high, associated with elevated potential acidity. The proximity of permafrost is leading to lower soil temperatures, reducing the number of thaw days. However, under current climate warming, this site will progressively act as a source of CO 2 to the atmosphere. On the other hand, peatlands could be formed due snow/ice melting, storing large amounts of carbon. The balance of uptake and release of CO 2 needs to be further researched in Maritime Antarctica, to elucidate the current dynamic for other different ice-free areas.

Cette thèse s'est déroulée dans le cadre du projet ANR FOSTER, "FOuille de données Spatio-Temporelles : application à la compréhension et à la surveillance de l'ERosion" (ANR-2010-COSI-012-02, 2011-2014). Dans ce contexte, nous nous sommes intéressés à la modélisation de données spatio-temporelles dans des graphes enrichis de sorte que des calculs de motifs sur de telles données permettent de formuler des hypothèses intéressantes sur les phénomènes à comprendre. Plus précisément, nous travaillons sur la fouille de motifs dans des graphes relationnels (chaque noeud est identifié de fa\c con unique), attribués (chaque noeud du graphe est décrit par des attributs qui sont ici numériques), et dynamiques (les valeurs des attributs et les relations entre les noeuds peuvent évoluer dans le temps). Nous proposons un nouveau domaine de motifs nommé motifs de co-évolution. Ce sont des triplets d'ensembles de noeuds, d'ensembles de pas de temps et d'ensembles d'attributs signés, c'est à dire des attributs associés à une tendance (croissance,décroissance). L'intérêt de ces motifs est de décrire un sous-ensemble des données qui possède un comportement spécifique et a priori intéressant pour conduire des analyses non triviales. Dans ce but, nous définissons deux types de contraintes, une contrainte sur la structure du graphe et une contrainte sur la co-évolution de la valeur des attributs portés par les noeuds. Pour confirmer la spécificité du motif par rapport au reste des données, nous définissons trois mesures de densité qui tendent à répondre à trois questions. À quel point le comportement des noeuds en dehors du motif est similaire à celui des noeuds du motif ? Quel est le comportement du motif dans le temps, est-ce qu'il apparaît soudainement ? Est-ce que les noeuds du motif ont un comportement similaire seulement sur les attributs du motif ou aussi en dehors ? Nous proposons l'utilisation d'une hiérarchie sur les attributs comme connaissance à priori de l'utilisateur afin d'obtenir des motifs plus généraux et adaptons l'ensemble des contraintes à l'utilisation de cette hiérarchie. Finalement, pour simplifier l'utilisation de l'algorithme par l'utilisateur en réduisant le nombre de seuils à fixer et pour extraire uniquement l'ensemble des motifs les plus intéressants, nous utilisons le concept de ``skyline'' réintroduit récemment dans le domaine de la fouille de données. Nous proposons ainsi trois algorithmes MINTAG, H-MINTAG et Sky-H-MINTAG qui sont complets pour extraire l'ensemble de tous les motifs qui respectent les différentes contraintes. L'étude des propriétés des contraintes (anti-monotonie, monotonie/anti-monotonie par parties) nous permet de les pousser efficacement dans les algorithmes proposés et d'obtenir ainsi des extractions sur des données réelles dans des temps raisonnables
This thesis was conducted within the project ANR FOSTER, ``Spatio-Temporal Data Mining: application to the understanding and monitoring of erosion'' (ANR-2010-COSI-012-02, 2011-2014). In this context, we are interested in the modeling of spatio- temporal data in enriched graphs so that computation of patterns on such data can be used to formulate interesting hypotheses about phenomena to understand. Specifically, we are working on pattern mining in relational graphs (each vertex is uniquely identified), attributed (each vertex of the graph is described by numerical attributes) and dynamic (attribute values and relations between vertices may change over time). We propose a new pattern domain that has been called co-evolution patterns. These are trisets of vertices, times and signed attributes, i.e., attributes associated with a trend (increasing or decreasing). The interest of these patterns is to describe a subset of the data that has a specific behaviour and a priori interesting to conduct non-trivial analysis. For this purpose, we define two types of constraints, a constraint on the structure of the graph and a constraint on the co-evolution of the value worn by vertices attributes. To confirm the specificity of the pattern with regard to the rest of the data, we define three measures of density that tend to answer to three questions. How similar is the behaviour of the vertices outside the co-evolution pattern to the ones inside it? What is the behaviour of the pattern over time, does it appear suddenly? Does the vertices of the pattern behave similarly only on the attributes of the pattern or even outside? We propose the use of a hierarchy of attributes as an a priori knowledge of the user to obtain more general patterns and we adapt the set of constraints to the use of this hierarchy. Finally, to simplify the use of the algorithm by the user by reducing the number of thresholds to be set and to extract only all the most interesting patterns, we use the concept of ``skyline'' reintroduced recently in the domain of data mining. We propose three constraint-based algorithms, called MINTAG, H-MINTAG and Sky-H-MINTAG, that are complete to extract the set of all patterns that meet the different constraints. These algorithms are based on constraints, i.e., they use the anti-monotonicity and piecewise monotonicity/anti-monotonicity properties to prune the search space and make the computation feasible in practical contexts. To validate our method, we experiment on several sets of data (graphs) created from real-world data

Thesis (M.S.) -- Worcester Polytechnic Institute.
Keywords: mining complex data; temporal association rules; computer system performance; stock market analysis; sleep disorder data. Includes bibliographical references (p. 79-85).

Dans le domaine de la biologie développementale, un des principaux défis est de comprendre comment des tissus multicellulaires, à l'origine indifférenciés, peuvent engendrer des formes aussi complexes que celles d'une fleur. De part son implication dans l'organogenèse florale, l'auxine est une phytohormone majeure. Nous avons donc déterminé son réseau binaire potentiel, puis y avons appliqué des modèles de clustering de graphes s'appuyant sur les profils de connexion présentés par ces 52 facteurs de transcription (FT). Nous avons ainsi pu identifier trois groupes, proches des groupes biologiques putatifs: les facteurs de réponse à l'auxine activateurs (ARF+), répresseurs (ARF-) et les Aux/IAAs. Nous avons détecté l'auto-interaction des ARF+ et des Aux/IAA, ainsi que leur interaction, alors que les ARF- en présentent un nombre restreint. Ainsi, nous proposons un mode de compétition auxine indépendent entre ARF+ et ARF- pour la régulation transcriptionelle. Deuxièmement, nous avons modélisé l'influence des séquences de dimérisation des FT sur la structure de l'interactome en utilisant des modèles de mélange Gaussien pour graphes aléatoires. Les groupes obtenus sont proches des précédents, et les paramètres estimés nous on conduit à conclure que chaque sous-domaine peut jouer un rôle différent en fonction de leur proximité phylogénétique.Enfin, nous sommes passés à l'échelle multi-cellulaire ou, par un graphe spatio-temporel, nous avons modélisé les premiers stades du développement floral d'A. thaliana. Nous avons pu extraire des caractéristiques cellulaires (3D+t) de reconstruction d'imagerie confocale, et avons démontré la possibilité de caractériser l'identité cellulaire en utilisant des méthodes de classification hiérarchique et des arbres de Markov cachés
A striking aspect of flowering plants is that, although they seem to display a great diversity of size and shape, they are made of the same basics constituents, that is the cells. The major challenge is then to understand how multicellular tissues, originally undifferentiated, can give rise to such complex shapes. We first investigated the uncharacterised signalling network of auxin since it is a major phytohormone involved in flower organogenesis.We started by determining the potential binary network, then applied model-based graph clustering methods relying on connectivity profiles. We demonstrated that it could be summarise in three groups, closely related to putative biological groups. The characterisation of the network function was made using ordinary differential equation modelling, which was later confirmed by experimental observations.In a second time, we modelled the influence of the protein dimerisation sequences on the auxin interactome structure using mixture of linear models for random graphs. This model lead us to conclude that these groups behave differently, depending on their dimerisation sequence similarities, and that each dimerisation domains might play different roles.Finally, we changed scale to represent the observed early stages of A. thaliana flower development as a spatio-temporal property graph. Using recent improvements in imaging techniques, we could extract 3D+t cellular features, and demonstrated the possibility of identifying and characterising cellular identity on this basis. In that respect, hierarchical clustering methods and hidden Markov tree have proven successful in grouping cell depending on their feature similarities

To optimize irrigation water use, temporal and spatial sensor-based data related to soil water content were integrated. Nine locations in a 37-ha agricultural field were selected using field elevation and soil ECa maps for monitoring the soil matric potential and temperature at four depths (18, 48, 79 and 109 cm) with a wireless sensor network. Using a linear regression approach, a series of time-specific equations were developed to quantify both the temporal and spatial soil water stress status through a Water Stress Index (WSI). The WSI was estimated using soil matric potential measurements along with supplemental soil characteristics, such as site-specific soil matric potential corresponding to 25% soil water depletion that was derived based on soil physical properties. Further analysis was performed to quantify the percentage of the field that undergoes a potential shortage in water supply. These results could be used to optimize irrigation scheduling and to assess the potential for variable-rate irrigation. The second study investigated the way in which the WSI prediction quality is affected by the number and placement of temporal soil water content monitoring sites. The concept, potentially, could be used to investigate a variety of site-specific crop management strategies. It was developed to assess WSI predictability in context that the modeled relationship between WSI and spatial field data (ECa and elevation) is not perfect at any given point of time. The established regression model between ECa, field topography maps and WSI from the first study was applied to construct WSI maps representing a specific point in time in six experimental fields with different crop growing conditions located in Nebraska, USA. Artificial regression error models with different degrees of spatial structure were superimposed onto these maps to simulate actual WSI distribution across the fields. Both random and optimized monitoring site placement strategies were evaluated in terms of the ability to predict the simulated WSI maps. The results showed that it was necessary to optimize the selection when the number of monitoring sites was low. However, a random placement method was equally efficient when the number of monitoring sites was high. Careful selection of representative field areas representing significant field areas with extreme conditions should allow only 2 or 3 monitoring sites to produce results with relatively low WSI prediction error.Through the process of water management optimization, it was noted that the ability to detect site-specific water storage capacity is an important task. Since it is related to the change of soil physical properties with depth, a third study was conducted to develop a dynamic scanning of soil profile tools using a galvanic contact resistivity approach. Transmitting and receiving electrodes were configured in an equatorial dipole array. An automated scanner system has been developed and tested in the agricultural field environment with different soil profiles. While operating in the field, the distance between the current injecting and measuring pairs of rolling electrodes was varied continuously from 40 to 190 cm. The resulting scans were evaluated against 1-m deep soil profiles and that of an electromagnetic induction instrument at various depths, up to 3 m.
Pour atteindre l'utilisation optimale de l'eau d'irrigation, des données spatio-temporelles provenant de sondes et reliées au contenu en eau du sol ont été intégrées. Ainsi, dans un champ agricole de 37 hectares, neuf sites ont été sélectionnés en utilisant les cartes d'élévation et de CEa du sol afin d'assurer le suivi du potentiel matriciel et de la température du sol à quatre profondeurs (18, 48, 79 et 109 cm) avec un réseau de capteurs sans fil. Utilisant une approche de régression linéaire, une série d'équations spécifiques au temps a été développée pour quantifier l'état de stress hydrique du sol dans le temps et l'espace à l'aide d'un Indice de Stress Hydrique (ISH). L'ISH a été estimé en utilisant des mesures de potentiel matriciel du sol combiné à ses caractéristiques supplémentaires, telles que celles calculées à partir de ses propriétés physiques et du potentiel matriciel spécifique au site correspondant à un appauvrissement de 25% des eaux du sol. Une analyse additionnelle a permis de quantifier la fraction du site ayant un potentiel d'approvisionnement en eau déficitaire. Ces résultats pourraient être utilisés afin d'optimiser la planification de l'irrigation et d'évaluer le potentiel d'irrigation à débits variables.La seconde étude a permis un examen plus approfondi de la qualité de prédiction de l'ISH influencé par le nombre et l'emplacement de sites chronologiques de surveillance du contenu hydrique du sol. Le concept pouvant potentiellement être utilisé pour étudier une diversité de stratégies de gestion de cultures a été développé afin d'évaluer la prévisibilité de l'ISH en tenant compte de la relation imparfaite entre cet indice et les données spatiales à tout temps donné. Le modèle de régression établi entre la CEa, les cartes topographiques du champ et l'ISH de la première étude a été appliqué afin de construire des cartes d'ISH représentant un moment spécifique pour six champs expérimentaux sous différentes conditions de croissance au Nebraska, USA. Des modèles artificiels d'erreur de régression avec différents degrés de structure spatiale ont été superposés sur ces cartes pour simuler la distribution réelle de l'ISH à travers ces champs. Autant de stratégies aléatoires et optimisées de placement de sites de surveillance ont été évaluées en termes de leur habilité à prédire les cartes d'ISH simulées. Les résultats démontrent qu'il était nécessaire d'optimiser la sélection de sites de surveillance lorsque leur nombre était bas. Cependant, la méthode de placement aléatoire était tout aussi efficace lorsque le nombre de sites était élevé. Une sélection rigoureuse des régions du champ permettant de représenter ses aires significatives avec des conditions extrêmes devrait permettre la production de résultats ayant une erreur de prédiction de l'ISH très basse à partir de seulement deux ou trois sites de surveillance.À travers le processus d'optimisation de la gestion de l'eau, il a été noté que l'aptitude à détecter la capacité d'emmagasinement d'eau spécifique au site est une tâche importante. Puisqu'elle est liée au changement de propriétés physiques du sol avec la profondeur, la troisième étude a été menée afin de développer un outil de balayage (scan) dynamique des profils du sol en utilisant une approche de résistance du contact galvanique. Les électrodes émettrices et réceptrices ont été configurées suivant un dispositif dipôle équatorial. Un système de scanner automatisé a été développé et testé dans un environnement de terre agricole avec différents profils de sol. Lors de l'utilisation sur le terrain, la distance entre les pairs d'électrodes roulantes d'injection et de mesure variait continuellement de 40 à 190 cm. Les balayages résultants ont été évalués avec des profils de sols de 1m de profondeur, alors que ceux fait à partir d'un appareil d'induction électromagnétique ont été évalués à des profondeurs variées allant jusqu'à 3m.

This study set out to explore the patterns and determinants of contemporary species distribution in a fynbos landscape based on information on 1) physical habitat characteristics, 2) past disturbance regime, 3) intrinsic properties of individual species and 4) temporal change in communities. The body of the thesis is divided into four parts covering each of these aspects individually. Each chapter has been written up as an individual paper and thus includes some repetition as well as cross-referencing. Each chapter includes a detailed rationale for the study in the introduction, as well as methods, results and a discussion of the findings. Chapter 2 describes the patterns of vegetation units in the Cape of Good Hope Nature Reserve and provides a quantitative assessment of the importance of physical site features as determinants of these units. These results are compared with the vegetation classifications of the area derived in earlier studies by Taylor (1984b) and Cowling et al. (1996a). Chapter 3 is the first study in fynbos to partition the variance in vegetation pattern into that explained by physical site factors and that explained by the recent disturbance regime. The study explores the role of 30 years of fire and alien plant infestations in influencing species distribution at the community and landscape scale. While a number of studies have explored spatial determinants of diversity and pattern in fynbos, temporal change within communities has been neglected. High levels of species turnover through time, as a result of colonisation and extinction, could be an important component of diversity at the landscape scale. Hence Chapters 4 and 5 both explore aspects of temporal dynamics in fynbos. The objectives of Chapter 4 are to determine the stability of populations at the landscape scale over a 30-year period and to establish the determinants of local extinction of species. Information on the stability of species over time and the attributes which enable species to persist or go extinct are important for understanding potential impacts of management practices as well as the importance of temporal dynamics in influencing spatial patterns. This is especially appropriate in the context of the results of Chapter 3, which suggest that a high proportion of the variance in species composition is unexplained despite the inclusion of physical factors, and past disturbance regime. The fifth chapter provides a descriptive account of the change in vegetation composition over a 30-year period. It is recommended that those readers not familiar with the fynbos system read it as it provides an overview of a variety of aspects of fynbos dynamics. Its objective is to show how the various components of the disturbance regime, as well as fluctuations in abundance of overstorey Proteaceae and their resultant competitive effects can influence community composition. The final chapter is a general discussion that summarises the major findings of the study.

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The fruitculture is an important component of Brazilian agribusiness assuming prominence in the economy of the state of Rio Grande do Sul (RS). The municipality of Pelotas, located in the south part of RS state, is responsible for 90% of peach production having adequate conditions of climate and soil for its production. One of the main problems faced by fruit farmers is the management of the peach orchard, which has been homogeneously managed, without considering the spatial and temporal variability of soil, plant and climate attributes in the peach orchard. Therefore, some aspects deserve attention from researchers, among them we can highlight the knowledge of the physical environment in which the peach tree grows. This work had as objectives: i. to evaluate the relationship between soil hydric-physical and crop attributes through the canonical correlation analysis, ii. to determine the spatial and temporal structures of soil hydric-physical, crop and climate attributes, applying geostatistics analysis. The work was conducted in an experimental area, located in the city of Morro Redondo-RS, cultivated with 18 line peach crops, cv. Esmeralda, totaling 1,450 plants. In this area was established a experimental grid consisted of 101 experimental peach trees. At a distance of 0.50m to the right side of each crop tree, trenches were opened to collect disturbed and undisturbed soil samples to determine the following soil hydric-physical attributes, in the 0.00-0.10m and 0.10-0.20m soil layers: sand, silt and clay contents, soil bulk density, soil total porosity, soil macro- and micro-porosities, and volumetric soil water content. We also evaluated the following peach crop attributes in the years of 2010 and 2011: trunk diameter, size of the fruit/plant, total number of fruits/plant, fresh mass of fruits, fruit firmness, brix content and crop productivity. The attributes of climate air temperature and relative humidity were also evaluated in the peach orchard. All data sets were submitted to descriptive statistical analysis. The correlation between soil and crop attributes was evaluated by canonical correlation analysis. The spatial and temporal variability structures of all data sets were evaluated by geostatistics as well as the relationship between them. Results show that the canonical correlation analysis identified the highest correlation coefficients of soil micro-porosity and clay content variables and peach productivity, and that the geostatistical analysis allowed establishing homogeneous management zones of soil, crop and climate attributes as well as to infer, visually, spatial inter-relationships between variables. The association of soil, crop and climate maps indicates that future differentiated managements of agricultural practices on the peach orchard should be based on the spatial distribution of these variables aiming rational water and fertilizer applications to preserve natural resources in the agricultural farmers.
A fruticultura é um importante componente do agronegócio brasileiro assumindo destaque na economia do estado do Rio Grande do Sul (RS). O município de Pelotas, localizado no sul do RS, é responsável por 90% da produção de pêssego, possuindo condições adequadas de clima e solo para a sua produção. Um dos principais problemas enfrentados pelos produtores de frutas é o manejo do pomar, que tem sido realizado de forma homogênea, sem considerar a variabilidade espacial e temporal dos atributos do solo, da planta e do clima dentro do pomar. Desta forma, alguns aspectos merecem atenção dos pesquisadores, dentre os quais, pode-se destacar o conhecimento do ambiente físico no qual o pessegueiro se desenvolve. Este trabalho teve como objetivos avaliar a relação entre os atributos físico-hídricos do solo e da planta por meio da análise de correlação canônica, determinar a estrutura de correlação espacial e temporal dos atributos físico-hídricos do solo, da planta de pessegueiro e do clima, por meio da técnica de geoestatística. O trabalho foi conduzido em uma área experimental, localizada no município do Morro Redondo-RS, cultivada com a cultivar de pêssego Esmeralda com 18 linhas, totalizando 1.450 plantas, onde foi estabelecida uma malha experimental composta por 101 plantas. A 0,50m do lado direito da cada planta, foram abertas trincheiras para a coleta de amostras deformas e indeformadas de solo para determinação dos atributos físico-hídricos, nas profundidades de 0,00-0,10m e de 0,10-0,20m: teores de areia, silte e argila, densidade do solo, porosidade total, macro e microporosidade do solo e umidade volumétrica. Também foram avaliados os seguintes atributos da planta nos anos de 2010 e 2011: diâmetro do tronco, tamanho do fruto/planta, número total de frutos/planta, massa fresca dos frutos, firmeza de polpa, teor de brix e produtividade. Os atributos do clima temperatura do ar e umidade relativa do ar também foram avaliados dentro do pomar. Todos os conjuntos de dados foram submetidos a análise exploratória por meio da estatística descritiva. A análise de correlação canônica foi aplicada para analisar as inter-relações entre as variáveis do solo e da planta, enquanto que, a geoestatística foi aplicada para avaliar a estrutura de correlação espacial e temporal de todos os dados bem como relação entre eles. Resultados mostram que a análise de correlação canônica permitiu identificar as variáveis do solo argila e microporosidade como as mais fortemente correlacionadas com a produtividade do pessegueiro e que a análise geoestatística permitiu delimitar as zonas homogêneas dos atributos do solo, da planta e do clima bem como inferir visualmente sobre as inter-relações espaciais entre as variáveis. A associação dos mapas das variáveis do solo, da planta e do clima indica que os futuros manejos diferenciados de práticas agrícolas deverão se basear na distribuição espacial das variáveis no pomar de pessegueiro visto que isto possibilitará a racionalização da aplicação de insumos e de água e a preservação dos recursos naturais na propriedade.

Um dos grandes desafios em mineração de dados é a integração de dados temporais ao seu processo. Existe um grande número de aplicações emergentes que envolvem dados temporais, incluindo a identificação de transações fraudulentas em cartões de crédito e ligações telefônicas, a detecção de intrusão em sistemas computacionais, a predição de estruturas secundárias de proteínas, a análise de dados provenientes de sensores, entre muitas outras. Neste trabalho, tem-se interesse na classificação de séries temporais que representam sinais de áudio. Como aplicação principal, tem-se interesse em classificar sinais de insetos coletados por um sensor óptico, que deve ser capaz de contar e classificar os insetos de maneira automática. Apesar de serem coletados opticamente, os sinais capturados se assemelham a sinais de áudio. O objetivo desta pesquisa é comparar métodos de classificação por similaridade e por extração de atributos que possam ser utilizados no contexto da classificação de insetos. Para isso, foram empregados os principais métodos de classificação de sinais de áudio, que têm sido propostos para problemas como reconhecimento de instrumentos musicais, fala e espécies animais. Neste trabalho, é mostrado que, de modo geral, a abordagem por extração de atributos é mais eficaz do que a classificação por similaridade. Mais especificamente, os melhores resultados são obtidos com a utilização de coeficientes mel-cepstrais. Este trabalho apresenta contribuições significativas em outras aplicações, também relacionadas à análise de séries temporais e sinais de áudio, por similaridade e por extração de atributos
One of the major challenges in data mining is the integration of temporal data to its process. There are a number of emerging applications that involve temporal data, including fraud detection in credit card transactions and phone calls, intrusion detection in computer systems, the prediction of secondary structures of proteins, the analysis of data from sensors, and many others. In this work, our main interest is the classification of time series that represent audio signals. Our main interest is an application for classifying signals of insects collected from an optical sensor, which should count and classify insects automatically. Although these signals are optically collected, they resemble audio signals. The objective of this research is to compare classification methods based on similarity and feature extraction in the context of insects classification. For this purpose, we used the main classification methods for audio signals, which have been proposed for problems such as musical instrument, speech and animal species recognition. This work shows that, in general, the approach based on feature extraction is more accurate than the classification by similarity. More specifically, the best results are obtained with mel-frequency cepstrum coefficients. This work also presents significant contributions in other applications, also related to the analysis of time series and audio signals by similarity and feature extraction

Dans cette thèse, nous nous sommes intéressés à l'analyse de données spatio-temporelles. Plusieurs algorithmes de fouille de données ont été développés pour extraire des modèles locaux (appelés aussi "motifs") tels que les motifs séquentiels ou les sous-graphes dynamiques. Cependant, ces approches souffrent de plusieurs limitations lorsqu 'on traite des phénomènes spatio-temporels complexes. Ces domaines de motifs ne prennent pas en compte toutes les interactions spatio-temporelles possibles ou ne considèrent que des informations limitées sur les objets étudiés. Par exemple, les motifs séquentiels se concentrent sur les évolutions temporelles sans tenir compte des évolutions spatiales. En outre, la plus part des algorithmes d'extraction de sous-graphes étudient des graphes dynamiques labélisés. Cependant, ils ne considèrent qu'un seul attribut par nœud et ignorent les autres caractéristiques des objets étudiés. Dans ce manuscrit, nous proposons d'étudier un graphe dynamique attribué pour fournir une représentation plus riche des phénomènes spatio-temporels. L'extraction de motifs dans des graphes dynamiques attribués est une tâche particulièrement complexe car la structure du graphe, les nœuds et les attributs associés à chaque nœud peuvent changer dans le temps. Pour cela, nous avons défini un nouveau domaine de motifs appelé motifs récurrents. Ces motifs, qui sont des séquences de sous-graphes connexes, représentent des évolutions récurrentes des sous-ensembles d'attributs associés à des sous-ensembles de nœuds. Pour extraire ces motifs, nous avons développé un nouvel algorithme, appelé RPMiner, utilisant une stratégie originale basée sur des intersections successives de composantes connexes apparaissant dans la séquence. Nous avons utilisé plusieurs contraintes pour réduire l 'espace de recherche et rendre le calcul possible. Une étude expérimentale sur des jeux de données synthétiques et réels (réseau de co-auteurs DBLP et données de trafic aérien US Flight) montre la généricité de notre approche, l 'intérêt des motifs extraits et l'efficacité de notre algorithme. Nous avons effectué également une évaluation poussée de notre approche sur les données du projet INDESO (suivi de bassins aquacoles en Indonésie par imagerie satellitaire). Pour cela, un processus d' extraction de connaissances (KDD) complet a été développé : du prétraitement des données à la visualisation et à l 'interprétation des résultats. Il vise à mieux comprendre les pratiques des fermiers pour un développement durable de ces ressources côtières en Indonésie. Ce processus s'appuie tout d'abord sur une méthode automatique et robuste pour extraire les bassins d'aquacoles à partir d'images satellitaires à faible contraste. Ensuite, il utilise des méthodes d'extraction de motifs fréquents afin de mettre en avant certaines pratiques des fermiers. Pour cela, nous avons appliqué dans un premier temps un algorithme d'extraction de motifs séquentiels pour analyser l'évolution des bassins dans le temps et comprendre les pratiques des fermiers. En parallèle nous avons aussi appliqué notre algorithme RPMiner, qui prend en compte à la fois les dimensions spatiales et temporelles. Les motifs extraits ont été interprétés par des experts en aquaculture. Les résultats obtenus ont permis de confirmer certaines pratiques et d'en mettre en avant d'autres
In this thesis, we are interested in analyzing spatio-temporal data. Numerous algorithms have been developed to extract local models (also called "patterns") such as sequential patterns or dynamic subgraphs. However, these approaches suffer from severa!limitations when dealing with complex spatio-temporal phenomena. These pattern demains do not consider all possible spatio-temporal interactions or only consider limited information about studied objects. For example, sequential pattern mining methods focus on temporal evolutions without considering spatial ones. Besicles, most of graph mining algorithms study labeled graphs. They only consider one attribute per vertex instead of all object's characteristics. In our work, we propose to study dynamic attributed graph, because they provide a richer representation of spatio-temporal phenomena. Extraction of patterns in dynamic attributed graph is a particularly complex task because graph structure, vertices and attributes associated with each vertex can change over time. For this purpose, we define a new pattern domain called recurrent patterns. These patterns, which are sequences of connected ubgraph, œpreent recurrent evolutions of subsets of attributes associated to vertices. To extract these patterns, we develop a new algorithm, RPMiner, using an original strategy based on successive intersections of connected components. We use severa! constraints to reduce the search space and make the computation feasible. Experimental study on both syndetic and two real-world datasets (DBLP dataset and Domestic US Flight dataset) show the genericity of our approach, the interest of extracted patterns and the efficiency of our algorithm. We also do an in-depth experimental evaluation of our approach on the INDESO project data (aquaculture pond monitoring in lndonesia by satellite images). A complete KDD process has been developed: from pre-processing of data to visualization and interpretation of results. It aims to better understand farming practices for sustainable development of these coastal resources in Indonesia.This process is firstly based on an automatic and robust method to extract aquaculture ponds from low contrast satellite images. Next, this process extracts frequent patterns to highlight sorne farming practices. For this, we have firstly applied a sequential pattern mining to analyze temporal evolutions of aquaculture ponds and to understand farming practices. In parallel, we also apply our algorithm, RPMiner, which considers both spatial and temporal aspects. Extracted patterns were interpreted by aquaculture experts. Results confirm severa!practices and highlight ethers

Le présent travail concerne la reconstruction 3-D des structures coronaires à partir de deux vues en imagerie coronarographique RX. L'approche retenue vise à reconstituer des entités structurelles de haut niveau c. A. D des branches vasculaires à partir d'une segmentation préliminaire pour améliorer la reconstruction de l'arbre coronaire. Dans ce contexte, deux méthodes ont été évaluées: une méthode de mise en correspondance de chaînes attribuées qui permet de décrire et de mettre en correspondance des primitives "lignes" et une technique de recalage élastique au moyen de fonctions splines plaques minces appliquée sur une description par points des objets. La stratégie finalement adoptée pour reconstituer les branches vasculaires sur les séquences angiographiques, combine ces deux approches de mise en correspondance et associe un algorithme de programmation dynamique pour restaurer les parties de branches manquantes
We have proposed a method to improve the 3-D reconstruction of the coronary in a sequence of bi-plane angiograms. This method allows reconstituting high level structural entities from a preliminary low level segmentation by means of a matching technique (such as ASM and TPS-based registration) and perceptual grouping rules (directional continuity, colinearity, proximity, shape similarity, …). A temporal matching aimed to take advantage of the heart-induced motion to remove ambiguities related to the superposition or crossing of the structures. The missing parts of the branches were then assessed through a feedback to the original image. The centerline and contour completion were undertaken using a minimal path technique between disconnected components. It made use of a dynamic programming algorithm associated with a likelihood measure that relied on both geometric and intensity features

Contemporary urban life and functioning have become increasingly dependent on mobility. Having become an inherent constituent of urban dynamics, the role of urban moblity in influencing urban processes and morphology has increased dramat- ically. However, the relationship between urban mobility and spatial socio-economic structure has still not been thoroughly understood. This work will attempt to take a complex network theoretical approach to studying this intricate relationship through • the spatio-temporal evolution of ad-hoc developed network centralities based on the Google PageRank, • multilayer network regression with statistical random graphs respecting net- work structures for explaining urban mobility flows from urban socio-economic attributes, • and Graph Neural Networks for predicting mobility flows to or from a specific location in the city. Making both practical and theoretical contributions to urban science by offering methods for describing, monitoring, explaining, and predicting urban dynamics, this work will thus be aimed at providing a network theoretical framework for developing tools to facilitate better decision-making in urban planning and policy making.

L'analyse quantitative de la perfusion myocardique, i.e. l'estimation d'indices de perfusion segmentaires puis leur confrontation à des valeurs normatives, constitue un enjeu majeur pour le dépistage, le traitement et le suivi des cardiomyopathies ischémiques --parmi les premières causes de mortalité dans les pays occidentaux. Dans la dernière décennie, l'imagerie par résonance magnétique de perfusion (IRM-p) est la modalité privilégiée pour l'exploration dynamique non-invasive de la perfusion cardiaque. L'IRM-p consiste à acquérir des séries temporelles d'images cardiaques en incidence petit-axe et à plusieurs niveaux de coupe le long du grand axe du cœur durant le transit d'un agent de contraste vasculaire dans les cavités et le muscle cardiaques. Les examens IRM-p résultants présentent de fortes variations non linéaires de contraste et des artefacts de mouvements cardio-respiratoires. Dans ces conditions, l'analyse quantitative de la perfusion myocardique est confrontée aux problèmes complexes de recalage et de segmentation de structures cardiaques non rigides dans des examens IRM-p. Cette thèse se propose d'automatiser l'analyse quantitative de la perfusion du myocarde en développant un outil d'aide au diagnostic non supervisé dédié à l'IRM de perfusion cardiaque de premier passage, comprenant quatre étapes de traitement : -1.sélection automatique d'une région d'intérêt centrée sur le cœur; -2.compensation non rigide des mouvements cardio-respiratoires sur l'intégralité de l'examen traité; -3.segmentation des contours cardiaques; -4.quantification de la perfusion myocardique. Les réponses que nous apportons aux différents défis identifiés dans chaque étape s'articulent autour d'une idée commune : exploiter l'information liée à la cinématique de transit de l'agent de contraste dans les tissus pour discriminer les structures anatomiques et guider le processus de recalage des données. Ce dernier constitue le travail central de cette thèse. Les méthodes de recalage non rigide d'images fondées sur l'optimisation de mesures d'information constituent une référence en imagerie médicale. Leur cadre d'application usuel est l'alignement de paires d'images par appariement statistique de distributions de luminance, manipulées via leurs densités de probabilité marginales et conjointes, estimées par des méthodes à noyaux. Efficaces pour des densités jointes présentant des classes individualisées ou réductibles à des mélanges simples, ces approches atteignent leurs limites pour des mélanges non-linéaires où la luminance au pixel s'avère être un attribut trop frustre pour permettre une décision statistique discriminante, et pour des données mono-modal avec variations non linéaires et multi-modal. Cette thèse introduit un modèle mathématique de recalage informationnel multi-attributs/multi-vues générique répondant aux défis identifiés: (i) alignement simultané de l'intégralité de l'examen IRM-p analysé par usage d'un atlas, naturel ou synthétique, dans lequel le cœur est immobile et en utilisant les courbes de rehaussement au pixel comme ensemble dense de primitives; et (ii) capacité à intégrer des primitives image composites, spatiales ou spatio-temporelles, de grande dimension. Ce modèle, disponible dans le cadre classique de Shannon et dans le cadre généralisé d'Ali-Silvey, est fondé sur de nouveaux estimateurs géométriques de type k plus proches voisins des mesures d'information, consistants en dimension arbitraire. Nous étudions leur optimisation variationnelle en dérivant des expressions analytiques de leurs gradients sur des espaces de transformations spatiales régulières de dimension finie et infinie, et en proposant des schémas numériques et algorithmiques de descente en gradient efficace. Ce modèle de portée générale est ensuite instancié au cadre médical ciblé, et ses performances, notamment en terme de précision et de robustesse, sont évaluées dans le cadre d'un protocole expérimental tant qualitatif que quantitatif

A espacialização de atributos dos solos é necessária com vistas ao planejamento e monitoramento do solo. As imagens do satélite Landsat 5 Thematic Mapper (TM) são utilizadas em estudos relacionados aos recursos naturais por fornecerem informações da superfície das terras em áreas amplas e de difícil acesso. Nesse trabalho objetivou-se gerar uma imagem multitemporal de solo exposto através de imagens de satélite e, com ela, mapear atributos da superfície do solo. A área de estudo é a região de Piracicaba, SP, onde foram selecionadas treze imagens do Landsat TM. Amostras da camada mais superficial dos solos foram coletadas em 740 pontos, e nelas analisados vários atributos do solo. Por meio da reflectância espectral dos objetos das imagens de satélite foram obtidas informações de solo exposto e eliminados outros alvos. As imagens foram adquiridas em série histórica e sobrepostas, gerando uma composta final com solo exposto. Os atributos do solo que obtiveram boa correlação com as bandas dessa imagem foram quantificados por meio da técnica de regressão multivariada e espacializados. Mapas pré-existentes de geologia e pedologia auxiliaram no entendimento da variabilidade espacial da textura e cor dos solos na paisagem. A taxa de variação do solo exposto em uma imagem individual variou de 7 a 20 %, enquanto a unificada atingiu 53 % da área total. Valores de reflectância entre as bandas TM3 e TM4 contrapostos representando a linha do solo e curva espectral média de espectros de amostras de solos obtidas em laboratório apresentaram semelhança com as de satélite. Entre os atributos estudados, a argila obteve a melhor correlação com R2 de 0,75, erro baixo e RPD acima de 2. Outros atributos relacionados com a argila também obtiveram boa correlação, como matéria orgânica (MO) e capacidade de troca de cátions (CTC) com R2 de 0,4 e 0,34 respectivamente.
The knowledge of spatial distribution of soil attributes is necessary for soil planning and monitoring. Landsat 5 Thematic Mapper (TM) images are used in studies related to natural resources for providing the land surface information in large areas and in areas of difficult access. This work aimed to create a multi-temporal image of bare soil through satellite scenes and map soil attributes from the surface. The study area is located in Piracicaba region, SP, where thirteen Landsat TM scenes were selected. Samples of the soil superficial layer were collected at 740 points, and several soil properties were analyzed. Spectral reflectance of different objects from satellite images was obtained and only exposed soil information was selected. Images were acquired in historical series and overlapped, generating a final composed image with bare soil. Soil attributes that presented good correlation with the bands were quantified by multivariate regression and mapped. Pre-existing maps of geology and soil helped in understanding soil texture spatial variability and color in the landscape. The soil variation rate in an individual exposed image ranged from 7 to 20%, while the unified reached 53% of the total area. Obtained values of reflectance between TM3 and TM4 bands representing the soil line and average spectral curve of laboratory soil samples were similar to the satellite ones. Among the soil attributes studied, clay presented the best correlation with R2 value of 0.75, low error and RPD value above 2.0. Other attributes related to clay also presented good correlation, such as organic matter (OM) and cation exchange capacity (CEC) with R2 values of 0.4 and 0.34 respectively.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A variação espacial e temporal da emissão de CO2 do solo é influenciada por atributos do solo relacionados à produção e ao transporte do gás soloatmosfera. Entretanto, ainda são escassos estudos visando compreender o efeito da topografia sobre a variabilidade da emissão de CO2 do solo, especialmente em área de conversão para o sistema de colheita da cana-de-açúcar mecanizada sem queima. Este trabalho tem como objetivo estudar as variações da emissão de CO2 do solo, em área cultivada com cana-de-açúcar, com histórico de colheita mecanizada sem queima, sob diferentes formas do relevo e posições na encosta. Foram selecionadas uma área situada numa superfície côncava (CONC) e outras duas em posições contrastantes numa superfície linear (encosta superior – ESUP e encosta inferior – EINF). Foram conduzidas avaliações da emissão de CO2 e de atributos do solo, nas três áreas, em duas situações distintas: (1) em 2004, um mês após plantio da cana-de-açúcar, foram conduzidas avaliações em pontos aleatórios em cada uma das três áreas, num mesmo dia, sendo a emissão de CO2, temperatura e umidade do solo avaliados ao longo de 7 meses e, (2) em 2005, um mês após o corte mecanizado da cana-de-açúcar crua, foi caracterizada a variabilidade espacial da emissão de CO2 e demais atributos do solo, por meio da semivariância, nas mesmas posições topográficas. A emissão total de CO2 no período de 7 meses de estudo em 2004 foi 19,26, 23,03 e 22,29 Mg CO2 ha-1 nas áreas CONC, ESUP e EINF, respectivamente. A variação temporal da emissão foi explicada por uma relação exponencial com temperatura, e uma relação linear com umidade do solo. O valor de 10 Q , calculado para as posições CONC, ESUP e EINF, foi de 1,98 (±0,34), 1,81 (±0,49) e 1,71 (±0,31). O efeito da forma do relevo e da posição topográfica sobre a variação da emissão de CO2 do...
The spatial and temporal variation of soil CO2 emission is influenced by several soil attributes related to CO2 production and gas transport from soil to atmosphere. However, few studies aiming to understand the effect of topography on the variability of CO2 emissions exist, especially on the sugarcane harvest system without prior burning. The objective of this work was to study the spatial and temporal changes of the soil CO2 emission in an area cultivated with sugar cane, having a mechanized crop system, under different relief forms and slope positions. In a landscape it was selected one area located in a concave form (CONC) and two others located at superior (ESUP) and inferior (EINF) positions in a linear form. It was conducted measurements of soil CO2 emission and soil attributes at the three different locations in two different situations: (1) in 2004, one month after sugarcane plantation, measurements were conducted with randomized repetitions for each area in each sampling day, and soil CO2 emission, soil temperature and soil moisture were also monitored during a period of 7 months, and (2) in 2005, one month after sugarcane harvesting without burning, the spatial variability of soil CO2 emission and soil attributes were characterized by the semivariance in the same topographic positions. Total soil CO2 emission during this period was 19,26, 23,03 e 22,29 Mg CO2 ha-1 for CONC, ESUP e EINF areas, respectively. Temporal variability of soil CO2 emission was explained by an exponential function with soil temperature and a linear function with soil moisture. The 10 Q values were 1.98 (±0.34), 1.81 (±0.49) and 1.71 (±0.31) for CONC, ESUP and EINF, respectively. The effect of relief form and topographic position on soil CO2 emission variation was dependent on the time of measurement. Bulk density, macroporosity, penetration resistance, aggregation and oxidizable organic ...(Comlete abstract, click electronic access below)

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Strawberry crop is an important option for small properties, being of great relevance for people fixation at countryside and generation and maintenance of rural jobs. Studies related to soil attributes monitoring, which can be used as soil quality indicators, are important to evaluate the sustainability of agricultural practices and to point to sound environment management, aiming to its conservation. This work intended to analyze the spatial and temporal variability of the chemical and microbiological soil attributes during the strawberry crop cycle in fourteen rural properties affiliated to the Association of Strawberry Producers of Turuçu-RS, to identify and evaluate the potential impacts of irrigation water on these attributes and to propose actions to minimize these impacts if needed. In this way, deformed soil samples were collected in four different periods at depth 0-0.20 m, to determine their chemical attributes (organic matter, active and potential acidity, CEC and at pH 7.0, base saturation and aluminum saturation), microbiological (carbon and nitrogen of microbial biomass, basal respiration and metabolic quotient) and about fertility (total nitrogen, phosphorus, potassium, copper and zinc). In order to evaluate the mean values of all attributes along the time in each property was applied the LSD mean comparison test with significance to 5%. The spatial and temporal variability of all attributes were evaluataded by means of box plots. Results indicated that between the soil chemical indicators, the mean values of potential acidity presented the major significant variation along the time, while the mean values of aluminum saturation presented the minor variation. Between the soil microbiological indicators, the mean basal respiration presented the major significant variation along the time, while the mean values of nitrogen of microbial biomass presented the minor variation. Between soil fertility indicators the mean values of copper presented the major significant variation along the time, while the mean values of zinc presented the minor variation. With regard to the spatial and temporal variability of the chemical indicators it was found that organic matter presented the greatest amplitude and the aluminum saturation the lowest. Regarding to the spatial and temporal variability of the microbiological indicators it was found that carbon of microbial biomass presented the greatest amplitude while the metabolic quotient presented the lowest. Regarding to the spatial and temporal variability of the soil fertility indicators it was found that copper presented the greatest amplitude while zinc presented the lowest. The concentrations of phosphorus, potassium, copper and zinc presented high levels in all strawberry crops. The organic matter levels were classified as low in most strawberry crops. It was not possible to identify the impact of irrigation water over the chemical and soil fertility indicators, meanwhile, there was a possible impact over the microbiological indicators, specially over the carbon and nitrogen of microbial biomass and metabolic quotient.
A cultura do morango é uma importante alternativa para pequenas propriedades, sendo de grande importância para a fixação do homem no campo e para a geração e manutenção de emprego na área rural. Estudos relativos ao monitoramento dos atributos do solo, que podem ser utilizados como indicadores de qualidade do solo, são importantes para avaliar a sustentabilidade das práticas agrícolas, além de sinalizar o manejo adequado do ambiente visando à sua conservação. Em virtude disto, este trabalho teve como objetivos estudar a variabilidade espacial e temporal dos atributos químicos e microbiológicos do solo ao longo do ciclo de produção da cultura do morango em quatorze propriedades pertencentes a Associação de Produtores de Morango do município de Turuçu/RS, identificar e avaliar os possíveis impactos da água de irrigação sobre estes atributos e propor ações para minimizar estes impactos caso existirem. Para tal, foram coletadas, em quatro diferentes épocas e na profundidade de 0-0,20 m, amostras deformadas de solo em cada uma das propriedades, determinando seus atributos químicos (matéria orgânica, acidez ativa e potencial, CTC efetiva e pH 7,0, saturação por alumínio e saturação por bases), microbiológicos (carbono microbiano, nitrogênio microbiano, respiração basal e quociente metabólico) e de fertilidade (nitrogênio total, fósforo, potássio, cobre e zinco). Para verificar o comportamento dos valores médios de todos os atributos ao longo do tempo e em cada propriedade foi aplicado o teste de comparação de médias DMS, a nível de 5% de significância, enquanto que para avaliar a distribuição temporal e espacial de todos os atributos foram construídos gráficos em caixa. Os resultados indicaram que dentre os indicadores químicos do solo, os valores médios de acidez potencial foram os que mais diferiram significativamente ao longo do tempo, enquanto que os valores médios de saturação por alumínio foram os que menos diferiram; dentre os indicadores microbiológicos do solo, os valores médios de respiração basal foram os que mais diferiram significativamente ao longo do tempo, enquanto que os valores médios de nitrogênio microbiano foram os que menos diferiram ao longo do tempo; dentre os indicadores de fertilidade do solo, os valores médios de cobre foram os que mais diferiram significativamente ao longo do tempo, enquanto que os valores médios de zinco foram os que menos diferiram; quanto a variabilidade espacial e temporal dos indicadores químicos, foi constatado que a matéria orgânica apresentou a maior amplitude e a saturação por alumínio a menor; quanto a variabilidade espacial e temporal dos indicadores microbiológicos, foi constatado que o indicador carbono microbiano apresentou a maior amplitude e o quociente metabólico a menor; quanto a variabilidade espacial e temporal dos indicadores de fertilidade, foi constatado que o cobre apresentou a maior amplitude e o zinco a menor; as concentrações dos elementos fósforo, potássio, cobre e zinco encontram-se com elevados teores em todas as lavouras de morango; os teores de matéria orgânica foram classificados como baixos na maioria das lavouras de morango envolvidas neste estudo; não foi possível identificar o impacto da adição da água de irrigação sobre os indicadores químicos e de fertilidade do solo, entretanto, houve um possível impacto sobre os indicadores microbiológicos, principalmente, verificado sobre o carbono microbiano, nitrogênio microbiano e o quociente metabólico.

Le traité de la Disputatio Scoti est un exemple supplémentaire d'alchimie savante proche de la scolastique. Afin de mieux comprendre ce texte, il était nécessaire de considérer la place de l'alchimie dans la société médiévale occidentale et de donner une vue d'ensemble cohérente et détaillée de la question (les travaux existant sur ce thème sont bien souvent synthétiques et manquent d'unité). Mon étude est donc tout d'abord consacrée aux relations de l'alchimie avec la scolastique et traite plus largement des opinions sur cet art exprimées par les savants et les philosophes. Tout en présentant les contextes historiques et économiques durant lesquels se posent les questions de la fabrication de l'or artificiel et d'un élixir de longue vie, je décris ensuite les rapports connus entretenus par les princes laïques et ecclésiastiques avec l'alchimie. Une troisième partie traite de la Disputatio faussement imputée à Michel Scot, en propose un commentaire et une édition critique
The treatise of Disputatio Scoti is an additional example of an erudite alchemy in close conformity with the Scholastic philosophy. To better understand this text, we must examine the standing of alchemy within Western medieval society and present a coherent and detailed overview of this issue (existing works on this theme are often too synthetic or inconsistent). My study therefore focuses on the links between alchemy and the Scholastic philosophy as viewed by scholars and philosophers. After presenting the historical and economic context in which the questions for producing gold artificially and discovering a long-life elixir arose, I highlight the known connections between the lay and ecclesiastic princes and alchemy. The third part of my thesis deals with a comment and a critical edition of the Disputatio, wrongly ascribed to Michel Scot

L'analyse quantitative de la perfusion myocardique, i.e. l'estimation d'indices de perfusion segmentaires puis leur confrontation à des valeurs normatives, constitue un enjeu majeur pour le dépistage, le traitement et le suivi des cardiomyopathies ischémiques --parmi les premières causes de mortalité dans les pays occidentaux. Dans la dernière décennie, l'imagerie par résonance magnétique de perfusion (IRM-p) est la modalité privilégiée pour l'exploration dynamique non-invasive de la perfusion cardiaque. L'IRM-p consiste à acquérir des séries temporelles d'images cardiaques en incidence petit-axe et à plusieurs niveaux de coupe le long du grand axe du cœur durant le transit d'un agent de contraste vasculaire dans les cavités et le muscle cardiaques. Les examens IRM-p résultants présentent de fortes variations non linéaires de contraste et des artefacts de mouvements cardio-respiratoires. Dans ces conditions, l'analyse quantitative de la perfusion myocardique est confrontée aux problèmes complexes de recalage et de segmentation de structures cardiaques non rigides dans des examens IRM-p. Cette thèse se propose d'automatiser l’analyse quantitative de la perfusion du myocarde en développant un outil d'aide au diagnostic non supervisé dédié à l'IRM de perfusion cardiaque de premier passage, comprenant quatre étapes de traitement : -1.sélection automatique d'une région d'intérêt centrée sur le cœur; -2.compensation non rigide des mouvements cardio-respiratoires sur l'intégralité de l'examen traité; -3.segmentation des contours cardiaques; -4.quantification de la perfusion myocardique. Les réponses que nous apportons aux différents défis identifiés dans chaque étape s'articulent autour d'une idée commune : exploiter l'information liée à la cinématique de transit de l'agent de contraste dans les tissus pour discriminer les structures anatomiques et guider le processus de recalage des données. Ce dernier constitue le travail central de cette thèse. Les méthodes de recalage non rigide d'images fondées sur l'optimisation de mesures d'information constituent une référence en imagerie médicale. Leur cadre d'application usuel est l'alignement de paires d'images par appariement statistique de distributions de luminance, manipulées via leurs densités de probabilité marginales et conjointes, estimées par des méthodes à noyaux. Efficaces pour des densités jointes présentant des classes individualisées ou réductibles à des mélanges simples, ces approches atteignent leurs limites pour des mélanges non-linéaires où la luminance au pixel s’avère être un attribut trop frustre pour permettre une décision statistique discriminante, et pour des données mono-modal avec variations non linéaires et multi-modal. Cette thèse introduit un modèle mathématique de recalage informationnel multi-attributs/multi-vues générique répondant aux défis identifiés: (i) alignement simultané de l'intégralité de l'examen IRM-p analysé par usage d'un atlas, naturel ou synthétique, dans lequel le cœur est immobile et en utilisant les courbes de rehaussement au pixel comme ensemble dense de primitives; et (ii) capacité à intégrer des primitives image composites, spatiales ou spatio-temporelles, de grande dimension. Ce modèle, disponible dans le cadre classique de Shannon et dans le cadre généralisé d'Ali-Silvey, est fondé sur de nouveaux estimateurs géométriques de type k plus proches voisins des mesures d'information, consistants en dimension arbitraire. Nous étudions leur optimisation variationnelle en dérivant des expressions analytiques de leurs gradients sur des espaces de transformations spatiales régulières de dimension finie et infinie, et en proposant des schémas numériques et algorithmiques de descente en gradient efficace. Ce modèle de portée générale est ensuite instancié au cadre médical ciblé, et ses performances, notamment en terme de précision et de robustesse, sont évaluées dans le cadre d'un protocole expérimental tant qualitatif que quantitatif
Quantitative assessment of moycardium perfusion, i.e. computation of perfusion parameters which are then confronted to normative values, is a key issue for the diagnosis, therapy planning and monitoring of ischemic cardiomyopathies --the leading cause of death in Western countries. Within the last decade, perfusion magnetic resonance imaging (p-MRI) has emerged as a reference modality for reliably assessing myocardial perfusion in a noninvasive and accurate way. In p-MRI acquisitions, short-axis image sequences are captured at multiple slice levels along the long-axis of the heart during the transit of a vascular contrast agent through the cardiac chambers and muscle. Resulting p-MRI exams exhibit high nonlinear contrast variations and complex cardio-thoracic motions. Perfusion assessment is then faced with the complex problems of non rigid registration and segmentation of cardiac structures in p-MRI exams. The objective of this thesis is enabling an automated quantitative computer-aided diagnosis tool for first pass cardiac perfusion MRI, comprising four processing steps: -1.automated cardiac region of interest extraction; -2.non rigid registration of cardio-thoracic motions throughout the whole sequence; -3.cardiac boundaries segmentation; -4.quantification of myocardial perfusion. The answers we give to the various challenges identified in each step are based on a common idea: investigating information related to the kinematics of contrast agent transit in the tissues for discriminating the anatomical structures and driving the alignment process. This latter is the main work of this thesis. Non rigid image registration methods based on the optimization of information measures provide versatile solutions for robustly aligning medical data. Their usual application setting is the alignment of image pairs by statistically matching luminance distributions, handled using marginal and joint probability densities estimated via kernel techniques. Though efficient for joint densities exhibiting well-separated clusters or reducible to simple mixtures, these approaches reach their limits for nonlinear mixtures where pixelwise luminance appears to be a too coarse feature for allowing unambiguous statistical decisions, and for mono-modal with nonlinear variations and multi-modal data. This thesis presents a unified mathematical model for the information-theoretic multi-feature/multi-view non rigid registration, addressing the identified challenges : (i) simultaneous registration of the whole p-MRI exam, using a natural or synthetic atlas generated as a motion-free exam depicting the transit of the vascular contrast agent through cardiac structures and using local contrast enhancement curves as a feature set; (ii) can be easily generalized to richer feature spaces combining radiometric and geometric information. The resulting model is based on novel consistent k-nearest neighbors estimators of information measures in high dimension, for both classical Shannon and generalized Ali-Silvey frameworks. We study their variational optimization by deriving under closed-form their gradient flows over finite and infinite dimensional smooth transform spaces, and by proposing computationally efficient gradient descent schemas. The resulting generic theoretical framework is applied to the groupwise alignment of cardiac p-MRI exams, and its performances, in terms of accuracy and robustness, are evaluated in an experimental qualitative and quantitative protocol

The population structure of fishery resources and the impact of environmental factors over its productivity are important processes to be considered in fisheries management. Environmental factors could determine both, the success of larval drift as the population spatial structure and its changes of biomass. Considering this, two key elements in the adequate, sustained exploitation of any fishery should be considered; the biological attributes of the species and how these vary over time and space. Research is needed to obtain a more thorough understanding of these effects, how they vary, and how they relate to environmental factors. However, spatial processes rarely constitute an explicit consideration in the evaluation and management of marine invertebrate populations, but this is particularly important in processes in which larval drift acts as one of the main mechanisms of population expansion. The ecological concept metapopulation is widely used and accepted for understanding low-mobility marine populations, and its implications for fishery management purposes should be considered. In this work we show the environmental effect over distribution, abundance and spatial structure of nylon shrimp population (Heterocarpus reedi) off central Chile (25°-37°S) from trawling surveys carried out between 1996 and 2011. Environmental variables considered where sea surface concentration of chlorophyll-a and dissolved organic matter. Results show a geographical separation in population around 32°S. Shrimp density is higher in the southern zone, where concentration of chlorophyll-a and dissolved organic matter are high due to presence of river tributaries and coastal upwelling zones. In this area, the bulk of the adult population is concentrated, which could act as "source" population and thereby its influence on larval drift could explain both, the preponderance of juveniles in the northern area as the smallest size of its population (“pseudo-sink” population). In the southern area, a process of spatial and bathymetric expansion had driven the increase in population size over time, where the colonization and individual somatic growth had been the main mechanisms. We found that periods of good environmental conditions explain high densities of shrimp with a delay of two years, which might be related mainly with larval survival and enhanced recruitment and somatic growth. In order to do a cross check of this proposal, and based on a complementary information source, 17 years of biological data collected from nylon shrimp fishery off central Chile were analyzed. We analyze these data using generalized linear models and determine the factors responsible for changes in carapace length, body weight, maturity, and sex ratio. better physical conditions and reproductive attributes of H. reedi south of 32°S would be related with the best environmental and food conditions at this zone. For example, individuals are larger, females are longer at first maturity (CL50%), and mature females are less prevalent. We outline a theoretical foundation that can guide future research on H. reedi. We also suggest that future conservation measures consider biological attributes within a spatial context. Finally, in order to contrast different hypotheses of population structure and spatial connectivity proposed along this work, we proposed a length-based population model and analyzed the biologic and fishery information available since 1945 under three hypotheses, based on the connectivity rate of two subpopulations located to the north and south of 32°S. The results show that, statistically, several hypotheses can be used to explain the data. The most likely hypothesis is that of a metapopulation in which the south zone acts as a source population (reproductive refuge) and determines, partially or totally, the arrival of recruits in the north zone, thereby explaining the population increase over the last decade. According to our study, empirical evidence will strengthen the hypothesis of spatial connectivity and, given the implications for managing the fishery of this resource, special attention should be paid to the biological-fishery conditions recorded south of 32°S, caution in its exploitation levels and consider this zone as reproductive refuge of nylon shrimp.
L'estructura poblacional dels recursos pesquers i l'impacte dels factors ambientals sobre la productivitat són processos importants a tenir en compte per a la gestió de les seves pesqueries. Els factors ambientals poden determinar l'èxit de la deriva larvària, l'estructura espacial de la població, així com les variacions de la biomassa. Tenint en compte aquests aspectes, s’haurien de considerar dos elements clau per a una explotació adequada i sostinguda de qualsevol pesqueria: les característiques biològiques de les espècies i com aquestes poden variar en el temps i en l’espai, essent necessària la millora de la comprensió d'aquests efectes, com varien, i com es relacionen amb els factors ambientals. No obstant això, els processos espacials rarament són considerats explícitament en la valoració i gestió de les poblacions d'invertebrats marins, més quan aquests aspectes són particularment importants en els processos de deriva larval actuant de principal mecanisme d'expansió d'una població. El concepte ecològic de metapopulations és àmpliament utilitzat i acceptat per a la comprensió de les poblacions marines de baixa mobilitat, i les seves implicacions haurien de ser considerades a la gestió pesquera. En aquest treball es demostra l'efecte del medi en la distribució, abundància i estructura espacial de la població de la espècie de crustaci decàpode Heterocarpus reedi anomenada a Xile en castellà com a “Camarón nailon”. S’ha mostrejat aquesta espècie a a la zona central de Xile (25 ° - 37 ° S) a partir de la informació obtinguda en campanyes oceanogràfiques de pesca d'arrossegament fets entre els anys 1996 i el 2011, així com de les característiques de l’aigua superficial (concentració de clorofil·la α i de la matèria orgànica dissolta). Els resultats van mostrar una separació geogràfica de la població a 32 ° S, on la densitat de gambes és més gran, així com també la concentració de clorofil·la α i la dissolució de matèria orgànica, això darrer degut segurament a la presència d'afluents dels rius i zones d'aflorament costaner. En aquesta zona es concentra la major part de la població adulta i podria actuar com a població “font” i la seva influència en la deriva larvària explicaria tant la preponderància de juvenils en la zona nord així com una població menys abundant (població “pseudo-sumider”). A la zona sud, l'augment de mida de la població s'explica per un procés d'expansió espacial i batimètric a traves del temps, on la colonització i el creixement somàtic dels individus serien els principals mecanismes. Els períodes de condicions ambientals favorables explicarien les altes densitats de individus de l’espècie niló dos anys després. Aquestes condicions ambientals favorables podrien estar principalment relacionades amb la supervivència de les larves, l'èxit dels processos de reclutament i el posterior creixement somàtic. D'altra banda, i amb l’objectiu de fer una verificació dels resultats dalt explicats, i basant-se en una font d'informació complementària, es van analitzar 17 anys de dades biològiques recollides en mostrejos pesquers del “camaron nylon” davant de la costa central de Xile. Es van analitzar aquestes dades utilitzant models lineals generalitzats (GLM) per tal de determinar els factors responsables dels canvis en la longitud del cefalotòrax, el pes del cos, la maduresa sexual i la proporció de sexes. Es va determinar una notable heterogeneïtat espacial en les característiques biològiques dels individus de H. reedi. Els individus en millor condició es van trobar al sud de la latitud de 32 ° S i aquesta millor condició es va relacionar amb les millors condicions ambientals i de menjar en aquesta zona. Per exemple, els individus són més grans, les femelles assoleixen abans el tamany de primera maduresa (CL50%), i les femelles madures són menys freqüents. Amb aquests resultats es presenta una base teòrica que pot guiar la recerca sobre les poblacions de H. reedi tenint en compte les consideracions espacials en les futures mesures de conservació. Finalment, per poder comparar diferents hipòtesis sobre l'estructura de la població i connectivitat espacial proposades al llarg d'aquest treball, es presenta un model de població basat en la talla i s’ha analitzat la informació biològica i pesquera disponible des de 1945. S’han tingut en compte tres hipòtesis en funció de la taxa de connectivitat de les dues subpoblacions, es a dir, les situades al nord i al sud de 32 ° S. Els resultats van mostrar que, estadísticament, diverses hipòtesi es poden fer servir per a explicar les dades disponibles. La hipòtesi més versemblant és la d'una metapoblació en la qual la zona sud actua com a població font o refugi reproductiu. Aquesta població determina parcialment o totalment l'arribada de reclutes a la zona nord i podria explicar l'augment d'aquesta població trobat a l'última dècada. Segons el nostre estudi, la hipòtesi de connectivitat espacial ha de ser contrastada només amb l'evidència empírica. Tenint en compte les implicacions per a la gestió pesquera, s’hauria de prestar una especial atenció a les condicions biològico-pesqueres que es registren al sud de 32 ° S, tenir especial precaució als nivells d'explotació pesquera i considerar aquesta zona (sud del 32 ° S) com a refugi reproductiu a Xile de l’espècie H. reedi.

Resumo: A variação espacial e temporal da emissão de CO2 do solo é influenciada por atributos do solo relacionados à produção e ao transporte do gás soloatmosfera. Entretanto, ainda são escassos estudos visando compreender o efeito da topografia sobre a variabilidade da emissão de CO2 do solo, especialmente em área de conversão para o sistema de colheita da cana-de-açúcar mecanizada sem queima. Este trabalho tem como objetivo estudar as variações da emissão de CO2 do solo, em área cultivada com cana-de-açúcar, com histórico de colheita mecanizada sem queima, sob diferentes formas do relevo e posições na encosta. Foram selecionadas uma área situada numa superfície côncava (CONC) e outras duas em posições contrastantes numa superfície linear (encosta superior - ESUP e encosta inferior - EINF). Foram conduzidas avaliações da emissão de CO2 e de atributos do solo, nas três áreas, em duas situações distintas: (1) em 2004, um mês após plantio da cana-de-açúcar, foram conduzidas avaliações em pontos aleatórios em cada uma das três áreas, num mesmo dia, sendo a emissão de CO2, temperatura e umidade do solo avaliados ao longo de 7 meses e, (2) em 2005, um mês após o corte mecanizado da cana-de-açúcar crua, foi caracterizada a variabilidade espacial da emissão de CO2 e demais atributos do solo, por meio da semivariância, nas mesmas posições topográficas. A emissão total de CO2 no período de 7 meses de estudo em 2004 foi 19,26, 23,03 e 22,29 Mg CO2 ha-1 nas áreas CONC, ESUP e EINF, respectivamente. A variação temporal da emissão foi explicada por uma relação exponencial com temperatura, e uma relação linear com umidade do solo. O valor de 10 Q , calculado para as posições CONC, ESUP e EINF, foi de 1,98 (±0,34), 1,81 (±0,49) e 1,71 (±0,31). O efeito da forma do relevo e da posição topográfica sobre a variação da emissão de CO2 do ...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The spatial and temporal variation of soil CO2 emission is influenced by several soil attributes related to CO2 production and gas transport from soil to atmosphere. However, few studies aiming to understand the effect of topography on the variability of CO2 emissions exist, especially on the sugarcane harvest system without prior burning. The objective of this work was to study the spatial and temporal changes of the soil CO2 emission in an area cultivated with sugar cane, having a mechanized crop system, under different relief forms and slope positions. In a landscape it was selected one area located in a concave form (CONC) and two others located at superior (ESUP) and inferior (EINF) positions in a linear form. It was conducted measurements of soil CO2 emission and soil attributes at the three different locations in two different situations: (1) in 2004, one month after sugarcane plantation, measurements were conducted with randomized repetitions for each area in each sampling day, and soil CO2 emission, soil temperature and soil moisture were also monitored during a period of 7 months, and (2) in 2005, one month after sugarcane harvesting without burning, the spatial variability of soil CO2 emission and soil attributes were characterized by the semivariance in the same topographic positions. Total soil CO2 emission during this period was 19,26, 23,03 e 22,29 Mg CO2 ha-1 for CONC, ESUP e EINF areas, respectively. Temporal variability of soil CO2 emission was explained by an exponential function with soil temperature and a linear function with soil moisture. The 10 Q values were 1.98 (±0.34), 1.81 (±0.49) and 1.71 (±0.31) for CONC, ESUP and EINF, respectively. The effect of relief form and topographic position on soil CO2 emission variation was dependent on the time of measurement. Bulk density, macroporosity, penetration resistance, aggregation and oxidizable organic ...(Comlete abstract, click electronic access below)
Orientador: Newton La Scala Júnior
Coorientador: José Marques Júnior
Banca: Carlos Eduardo Pellegrino Cerri
Banca: Zigomar Menezes de Souza
Banca: Gener Tadeu Pereira
Banca: Wanderley José de Melo
Doutor

碩士
大同大學
電機工程研究所
90
Although many researches have been done in the area of content-based image representation, coding, and manipulation in the recent few years, content-based representation of video objects has not been fully explored. Content-based representation means to gather homogeneous objects in terms of color, texture, and motion. It starts at the segmentation with the homogeneity in color, texture and motion. In this thesis, we have presented a video segmentation system using spatial and temporal attributes. Motion estimation itself is not accurate due to the boundary problems and the noise in the frames. The result of motion segmentation is affected by the precision of motion estimation; as a result, it can only give a rough region of the moving object. On the other hand, color segmentation can give more accurate region edges, but the color-segmented regions usually scatter in a frame. Therefore, we integrate spatial segmentation results and temporal segmentation results to produce robust and accurate segmentation results. Our system consists of four major blocks: (i) intra-frame segmentation, (ii) motion field estimation, (iii) motion segmentation, and (iv) inter-frame segmentation. The intra-frame segmentation block produces a spatial segmentation for each image frame based on only the spatial information of the image. The technique we adopted is a graph-based method. The motion field estimation block estimates a dense flow field for each two consecutive frames by using the well-known Horn and Schunsk’s optical flow method. A Weighted Vector Median (WVM) filter is adopted to regulate the noisy dense flow field. The motion segmentation block performs the segmentation on the dense flow field obtained from the motion estimation block. We adopt a k-means clustering algorithm based on affine motion model for this task. Finally, the inter-frame segmentation block integrates spatial segmentation results obtained from the intra-frame segmentation block and temporal segmentation results obtained from the motion segmentation block to produce desired semantic objects. The experimental results show that our algorithm is capable of producing meaningful and accurate semantic objects. The resulting semantic objects are suitable for MPEG-based video applications in content-based representation, manipulation, and coding.

碩士
臺中技術學院
企業管理系事業經營碩士班
99
This research explored the impact of temporal distance on consumers’ attribute preference. Study 1 demonstrated that temporal distances influence the consumer preferences between reliability and performance attributes, when a purchase is proximal (distant), consumers will prefer the product that reliability (performance) attributes perform better than the product that performance (reliability) attributes perform better. Study 2 demonstrated that temporal distances influence the consumer preferences between utilitarian and hedonic attributes, when a purchase is proximal (distant), consumers will prefer the product that utilitarian (hedonic) attributes perform better than the product that hedonic (utilitarian) attributes perform better.

碩士
國立清華大學
資訊工程學系所
105
Predicting continuous facial emotions is essential to many applications in human-computer interaction. In this paper, we focus on predicting the two dimensional emotions: valence and arousal, to interpret the dynamically yet subtly changed facial emotions. We propose an Attribute-based Siamese Temporal Network (AST-Net), which includes a discrete emotion CNN model and a Stacked-LSTM, to incorporate both the spatial facial attributes and the long-term dynamics into the prediction. The discrete emotion CNN model aims to extract attribute-related but pose- and identity-invariant features; and the Stacked-LSTM is used to characterize the dynamic dependency along the temporal domain. Furthermore, in order to stabilize the training procedure and also to derive a smoother and reliable long-term prediction, we propose to jointly learn the model from two temporally-shifted videos under the Siamese network architecture. Experimental results on AVEC2012 dataset show that the proposed AST-Net not only processes in real time (40.1 frames per second) but also achieves the state-of-the-art performance even when using the vision modality alone.

碩士
國立成功大學
企業管理學系
105
As the competition in today's market gets more intense, product excellence has become a marketing target for many companies. Many consumers tend to make buying decisions based on different product attributes. However, consumer habits are constantly changing all the same time. One of the biggest reasons for this is the rise of the internet. When consumers face a variety of product information, their degree of patience becomes more extreme. Sometimes people lack patience, and sometimes they don’t. Based on the above, both product attributes and consumers' various preferences of time might affect their purchasing decisions. To explore the relationship between products and consumers, this study takes an irrelevant product attribute, which implies a function, but in fact, cannot provide a substantial effect, as the target attribute. Furthermore, this study explores consumers’ final purchase intention under different combinations of an irrelevant product attribute and psychological temporal distance. There are four discoveries in this study: (1) when a product has an irrelevant attribute, the effect of brand communication is higher, as is purchase intention. (2) Psychological temporal distance has little moderating effect on a consumer’s decision. (3) Brand communication effect has a positive relationship with purchase intention. (4) Brand communication is a strong mediator between irrelevant product attributes and purchase intention. Irrelevant product attributes are important for consumer decisions. Conversely, psychological temporal distance does not have a significant effect on consumer decisions. Therefore, a company may try to focus more on implementing different product attributes on their product than controlling consumers’ psychological condition.

This thesis is concerned with the classification of accounting information from the recording phase through to the reporting phase. Various criticisms on the way information is presented in financial statements, especially in the balance sheet and income statement ware found in the literature. Classification models for accounting information have been proposed in the literature but the main disadvantages of these models are that they are inherently static in nature and do not embed the notion of time. To further test the various criticisms of present classification structures, 1) a comprehensive literature survey of the criticisms of present accounting classification structures as presented by researchers in the literature was conducted, 2) a questionnaire was prepared and sent out to companies in industry, academics as well as analysts in order to test these criticisms, and 3) an analysis of the financial statements (balance sheet and income statement) of 93 companies listed on The JSE Securities Exchange South Africa (JSE) was undertaken. The outcome of the above three (3) actions led to the following hypothesis: The current classification of accounting information, from the recording phase to reclassification in the reporting phase, does not supply users of such information with the necessary information for decision-making purposes. In this regard a comprehensive classification framework for accounting information is proposed, with the following properties: • A well-defined set of attributes will be used, ultimately to classify a transaction into a static sub-framework to aid decision-making. • Time will be used to classify a transaction at the time of recording and later to reclassify it at the time of reporting. • The proposed framework will guide the classifier as to how an item finds its way into a static structure. Classification has as its step the identification of all the attributes known at the time of recording and reporting of the items implicitly involved in a transaction. These attributes in essence define the items that are to be classified into a structure as well as allowing for relationships to be drawn among the said items. One of the advantages of classification is the creation of (new) knowledge or information. The utility of such information depends on the quality of the classification performed. Normally the responsibility for classification at both the recording and reporting phases rests with the accountant. The resultant classification should provide enough information to users of financial statements, especially financial managers, to allow them to reclassify the given information to suit their own needs. An important influence on a classification framework for accounting information is the various requirements put forward by a variety of users of such information. Some of these requirements may conflict with one another. It is proposed in this thesis that a distributed union of all requirements of users be taken and all conflicting requirements be removed from the union (i.e. simply put all requirements into one group and remove all those that conflict with one another). Classification is then performed for the result. Additional information may be supplied in the statements to cater for the requirements outside the result. The classification framework for accounting information proposed in this thesis is made up of three (3) sub-frameworks as follows: • A normative sub-framework that defines a number of attributes for a transaction and which is based on the recording (past) and reporting (present) phases of accounting information. This framework also takes transactions with future aspects into account • A decision sub-framework which follows directly on the normative sub-framework and which directs the classifier as to where a transaction should be classified in a final, static sub-framework. • A static sub-framework which shows where items implicitly involved in a transaction are finally classified. Classification frameworks are proposed for both the balance sheet and the income statement. The balance sheet framework embodies a temporal component, a decision component and a static structure. A different classification layout for the income statement, including a temporal component and a static structure, is also proposed in this thesis.
Thesis (DCom (Financial Management Sciences))--University of Pretoria, 2008.
Financial Management
unrestricted

碩士
國立臺中科技大學
企業管理系碩士班
104
The Behavioral Finance which researching scope sometimes bases on the Prospect Theory is prevailing nowadays. That is, when financial consumers are making investment decisions under the limited rationality, they would expect to gain higher reward by learning from past mistakes. This model of behavior always causes the scholars to embark on the study of the investment behavior from a psychology view. This study was constructed on the above theory, be used to personality characteristics and temporal distance as the main input variables. From the perspective of different time when events occur, people also quote the investment decision-making behavior theory, trying to understand the strategy preferences of individual on their investment risks, to explore the relationship of the financial consumer''s investment attribute and investment decision-making behavior. For the convenience of sampling, those are collected by financial management sector of a financial holding company in central Taiwan as the empirical object for the study. We design and send 250 copies of questionnaires and receive 210 valid copies of samples. The datas obtained were quantified in four dimensions in accordance with the purpose of research to establish research framework and hypothesis, regression analysis was adopted to the hypothesis step by step. Through the results of this study, it was found that: 1. The effect of financial consumer’s financial risk-taking tendency to investment attribute is significant positive. 2. The effect of financial consumer’s distance future to investment attribute is significant negative. 3. The effect of financial consumer’s personality characteristics to investment decision-making behavior is significant positive. 4. The effect of financial consumer’s distance future to investment decision-making behavior is significant negative. 5. The effect of financial consumer''s aggressive investment attribute to investment decision-making behavior is significant positive People’s perception of risk attitude and risk tolerance would have an impact on personality characteristics, thereby affecting the investment decision-making behavior. Recommendations to financial consumers and financial service providers were made by the research results： For financial consumers, they should understand their investment attribute before investing and get information about investment target. They should set up stop-loss point and take-profit point, reduce overreaction to event, avoid falling into intuitive error, and rely on in-depth thinking rather than discussing from community. For financial service providers, they should design suitable financial portfolio product, enhance two-way communication with financial consumer by holding financial talk and seminar, provide a self-review system of risk tolerance, teach investor to understand the new trend of investment risks, and avoid excessive marketing to financial consumers in case they lose their confidence when the investment result are not as they have expected. With the coming of Fin Tech in the future, at first, it is necessary to strengthen their economic analysis ability and focus on estate planning rather than marketing. Next, it is necessary to use large data analysis on financial technology more often to understand financial consumer''s psychological needs and ideas. By doing so, they may be able to provide customized services to create a win-win opportunity.

There are considerable expenditures by government and private forest industry to enhance the growth of forests and reduce time required for crop rotation. The effectiveness of some of these treatments is dependent on site productivity. In addition, as responsible stewards of the forest resource and habitat, it is important that the state of forests are actively monitored, especially in the face of a changing climate and increased rates of disturbance. This dissertation reports on the development of a method for estimating and mapping forest productivity. The Shawnigan Lake thinning and fertilization forest installation, established in 1971 by CFS, was selected as the study site largely for its rich mensuration history. Square treatment plots were 0.04ha in area and included two thinning levels (1/3 & 2/3 of the basal area), two fertilization treatments (224kg & 448kg N/ha) with repeated fertilizations and macronutrient experiments (S, P) and control plots. A sample of plots was selected for high precision ground based lidar reference surveys. In September of 2012 a multi-sensor airborne survey of SLP was conducted that collected high-density lidar (up to ~70pnts/m2) and VNIR imaging spectroscopy. A thorough empirical radiometric calibration was conducted in addition to a spatial calibration at the Victoria International Airport. A combination of area based height percentile, point density ratios and statistical moments with individual lidar tree metrics including height distribution and proximity metrics were generated. Topographic metrics were also generated from the lidar ground classified point cloud. A library of spectral indices was computed from the imaging spectrometer data, with an emphasis on those indices known to be associated with vegetation health. These metrics were summarized to the plot level for a coarse scale regression analysis. A control survey and ground based lidar was used to facilitate an individual tree based fine scale of analysis, where reference data could unambiguously be matched to airborne collected data through the projected positions. Regression analysis was conducted applying the best subset regression with exhaustive feature selection search criteria and included a critical evaluation of the resulting selected features. Models were investigated considering the data source and in combination, that is, lidar metrics were considered independent of spectroscopy as well as the converse, and lidar metrics in combination with spectral metrics. The contribution of this study is the revelation that existing area based point cloud metrics are highly correlated, potentially noisy and sensitive to variations in point density, resulting in unstable feature selection and coefficients in model building. The approach offered as an alternative is the gridded lidar treetops method, which is evidently lacking within the literature and which this study overwhelmingly advocates. Additionally, the breadth and diversity of metrics assessed, the size and quality of the reference data applied, and the fine spatial scale of analysis are unique within the research area. This study also contributes to the knowledge base, in that, productivity can be estimated by remote sensing technologies. The use of gridded generalizations of the individual tree approach reduced estimation errors for both structural and productivity attributes. At the plot-level, crown structure and crown health features best estimated productivity. This study emphasizes the dangers of empirical modeling; at the even-aged SLP installation, growth is strongly tied to structure and the extrapolation to other sites is expected to provide biased values. It is my perspective that physical lidar structural models of the dominant and co-dominant crown classes be used to augment spatially explicit tree and stand growth models. In addition, direct measures should be obtained by multi-temporal lidar surveys or as an alternative photogrammetric point clouds after an initial lidar survey to quantify growth and aid in calibrating growth models.
Graduate

Since European American settlement of the Intermountain Region, dramatic changes in vegetation composition and structure have occurred in the sagebrush steppe ecosystem. Western juniper (Juniperus occidentalis spp. occidentalis Vasek), although indigenous to the Intermountain Region, has increased since the late 1800s. Considerable work has been done documenting juniper woodland expansion in the Intermountain West, however, little is known about the environmental variables that influence rates of tree establishment and structural attributes of woodlands across landscapes. Most studies of western juniper have addressed site-specific questions at limited spatial scales. Consequently, there is a lack of research on broader scale patterns of woodland development occurring across heterogeneous landscapes. In addition, changes in the amount, composition, and structure of fuels during the transition from open sagebrush steppe communities to closed juniper woodlands have profound influences on the size, intensity, frequency, and behavior of fire. However, limited data exist quantifying changes in fuels during this transition, thus, consequences to fire behavior have been difficult to predict. The major impetus for the study was to determine the influence of environmental variables on rates and structural attributes of woodland development and associated changes in fuel loading characteristics during the transition from sagebrush steppe communities to closed juniper woodlands in the High Desert and Humboldt ecological provinces. The proportion of trees greater than 150 years old relative to trees less than 150 years suggest western juniper has greatly expanded in the Owyhee Mountains and on Steens Mountain since settlement of the areas. Ninety-five percent of the trees established after the 1850s. As evidenced by the presence of western juniper in 96% of plots sampled in this study, juniper is able to encroach upon a variety of plant alliances and under a broad range of environmental conditions over diverse landscapes. Although it appears the occurrence of western juniper within the woodland belt is not spatially limited by environmental or vegetative conditions, stand structural and fuel loading characteristics do vary considerably across heterogeneous landscapes. Total juniper density, density of dominant trees comprising the primary canopy, and certain live and dead fuels biomass very substantially with site potential. Spatial variation in stand structure and fuels may have significant implications to management of juniper at the landscape scale.
Graduation date: 2005

碩士
國立臺灣大學
商學研究所
97
The main goal of this study is to find out the effect of self-regulatory focus (promotion focus vs. prevention focus), temporal distance (the time gap between now and the timing when customer purchases this product), and product attribute (utilitarian attribute vs. hedonic attribute) on evaluation of product upgrades. Due to the fact that the influence of self-regulatory focus, temporal distance, and product attribute on product evaluation is a relative new issue in the academic area and the fact that this concept is very practical in the real business world, this study combines these four topics to discuss their effects on consumer’s preference and choice when confronting different ways of product upgrades. The main goals of this research were as follows: 1. Discuss how the consumers with different types of “regulatory focus” prefer and make different choices on different ways of “product upgrades.” 2. Discuss how the consumers facing different “temporal distance” prefer and make different choices of “product upgrades.” 3. Discuss how the consumers facing different “product attribute “ prefer and make different choices of “product upgrades. In the first part of the research, this paper discuss the effect of customers with different self-regulatory focus, different temporal distance, and different product attributes when they need to choose from general enhancement(to upgrade an ordinary product with similar ratio complied with every existing attributes) and focus enhancement(the way of upgrades focus certain attributes to promote). In the second part of this research, this paper discuss the effect of customers with different self-regulatory focus, different temporal distance, and different product attributes when they need to choose from other kinds of product upgrades : general alignable enhancement(the general upgrades which is similar to the ordinary one because both of them have exactly the same attributes) and general nonalignable enchancement(the general upgrades which adds new attributes to the old product and increases the level of dissimilarity between old and new products). Finally, in the last part of the research, this paper will focus on the effect of customers with different self-regulatory focus, different temporal distance, and different product attributes when they need to choose from focus alignable enhancement(the focus upgrades which is similar to the ordinary one because both of them have exactly the same attributes) and focus nonalignable enhancement(the focus upgrades which adds new attributes to the old product and increases the level of dissimilarity between old and new products). The conclusions of this study are as follows: 1. Whether the consumers with “promotion focus” or “prevention focus “, whether they face “half year ”or “two years” temporal distance, “utilitarian attribute ”or “hedonic attribute”, they prefer and are more willing to choose “general enhancement ”. However, the level of preference will decrease as customers face a product with hedonic attributes. In addition, when the customer with promotion focus face a product with hedonic attributes, the level of decrease is more obvious. 2. In the study with LCD TVs as the experimental product , the consumers with promotion focus prefer and are more willing to choose “general nonalignable enhancement” 3. In the study with mobile phones as the experimental product, the consumers with promotion focus prefer and are more willing to choose “focus nonalignable enhancement.” In the study with LCD TVs as the experimental product, the customers prefer and are more willing to choose “focus nonalignable enhancement “when they are with promotion focus or when they face an LCD TV with hedonic attributes.

碩士
國立臺灣大學
商學研究所
96
The main goal of this study was to find out the effect of self-regulatory focus, temporal distance and product attributes on preference and choice of product upgrades. On the one hand, the importance of “product upgrades” is increasing to the firms recently. On the other hand, the concepts of “self-regulatory focus” and “temporal distance” are often quoted to explain consumer behaviors nowadays. Also, different “product attributes” usually provoke different needs and preference. Based on above points, this study examined three main topics: (a) Discuss how “regulatory focus” affects consumers’ preference and choice on different ways of “product upgrades”. (b) Discuss how “temporal distance” affects consumers’ preference and choice on different ways of “product upgrades”. (c) Discuss how “product attributes” affects consumers’ preference and choice on different ways of “product upgrades”. This research took experiments with 2 (regulatory focus: promotion focus versus prevention focus) x 2 (temporal distance: distant future versus near future) x 2 (product attributes: hedonic attributes versus utilitarian attributes) between-subjects design. The conclusions of this study are as follows: 1. Consumers with promotion focus prefer nonalignable enhancement while consumers with prevention focus prefer alignable enhancement. 2. With longer temporal distance, consumers prefer nonalignable enhancement. 3. Consumers facing hedonic attributes prefer nonalignable enhancement and focus enhancement while consumers facing utilitarian attributes prefer alignable enhancement and general enhancement. Above all, this study found that firms can take self-regulatory focus, temporal distance and product attributes into account when choosing the most appropriate type of product upgrades.

碩士
國立中山大學
人力資源管理研究所
104
While the construal level theory (CLT) has been widely discussed in the consumer behavior domain, this study is aimed to extend the CLT to the recruitment research, in wish to realize whether people’s preference and attitudes toward the different job attributes change in different temporal distances. The study also discusses whether future time perspective (FTP) moderates the interaction effect of temporal distance and job attributes. The study applies a 2 (near future vs. distant future) × 2 (positive objective + negative subjective job attributes vs. positive subjective + negative objective job attributes) between-subjects factorial experiment design. The result shows that the objective job attributes have a stronger influence on peoples’ job pursuit intention and job/organization attraction in the distant future rather than in the near future; whereas subjective job attributes have a stronger influence in the near future rather than in the distant future, which are in contrast to the hypothesis 1 of this study. In addition, the study finds out that the interaction effect of temporal distance and job attributes is stronger for the people with higher FTP rather than the people with lower FTP, which is aligned with the hypothesis 2.

碩士
國立成功大學
資訊工程學系
107
Real estate prices have always been the lifeblood of an area's economy, or even a country’s economy. Real estate is the fundamental requirement of people’s lives and exerts impact on the prices of goods and labor. Thus, being able to forecast future trends in real estate prices would be of significant contribution to a country’s economic development. Past studies have mainly employed two methods to predict real estate prices: statistical correlation algorithms and artificial intelligence algorithms. However, these methods lack adequate consideration of the numerous factors influencing real estate prices and are thus impractical. We therefore proposed a method to predict real estate prices using deep learning and the spatial and temporal attributes of open data. Unlike methods used in the past, the proposed approach considers the temporal factors of the real estate itself in price prediction but also takes the spatial factors of the real estate surroundings into account. A case study was conducted in Xitun District of Taichung City, Taiwan. In this study, we constructed a novel space-time series graph that integrates the space and time information of real estate transactions so that we can consider the temporal and spatial factors that influence real estate prices at the same time, thereby increasing the accuracy of real estate price predictions. Furthermore, we discovered that the significantly large scope of real estate price data causes data normalization issues. We thus utilized fuzzy grouping to reduce the scope of data. The focus of fuzzification is that overall values are relative in nature, which enables us to choose different estate groups. Based on the above content, we constructed a system for real estate price prediction using deep learning. Experiment results demonstrated the validity of the proposed method.