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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Daylight operation of a sodium laser guide star

Hart, Michael, Jefferies, Stuart, Murphy, Neil 27 July 2016 (has links)
We report photometric measurements of a sodium resonance guide star against the daylight sky when observed through a tuned magneto-optical filter (MOF). The MOF comprises a sodium vapor cell in a kilogauss-level magnetic field between crossed polarizers and has a very narrow transmission profile at the sodium D-2 resonance of approximately 0.008 nm. Our observations were made with the 1.5 m Kuiper telescope on Mt. Bigelow, AZ, which has a separately mounted guide star laser projecting a circularly polarized single-frequency beam of approximately 6.5 W at 589.16 nm. Both the beam projector and the 1.5 m telescope were pointed close to zenith; the baseline between them is approximately 5 m. Measurements of the guide star were made on the morning of 2016 March 24 using an imaging camera focused on the beacon and looking through the full aperture of the telescope. The guide star flux was estimated at 1.20x10(6) photon/m(2)/s while at approximately 45 minutes after sunrise, the sky background through the MOF was 1100 photon/m(2)/s/arcsec(2). We interpret our results in terms of thermal infrared observations with adaptive optics on the next generation of extremely large telescopes now being built.
22

Geothermal resource assessment in shallow crust of Japan by three-dimensional temperature modeling using satellite imagery and well-logging dataset / 衛星画像と坑井検層データセットを用いた日本列島地殻表層の3次元温度分布モデリングと地熱資源評価

Tian, Bingwei 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18969号 / 工博第4011号 / 新制||工||1618(附属図書館) / 31920 / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 小池 克明, 教授 松岡 俊文, 教授 田村 正行 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
23

Physics-based radiometric signature modeling and detection algorithms of land mines using electro-optical sensors

Liao, Wen-Jiao 07 November 2003 (has links)
No description available.
24

Rangefinding in Fire Smoke Environments

Starr, Joseph Wesley 07 January 2016 (has links)
The field of robotics has advanced to the point where robots are being developed for use in fire environments to perform firefighting tasks. These environments contain varying levels of fire and smoke, both of which obstruct robotic perception sensors. In order to effectively use robots in fire environments, the issue of perception in the presence of smoke and fire needs to be addressed. The goal of this research was to address the problem of perception, specifically rangefinding, in fire smoke environments. A series of tests were performed in fire smoke filled environments to evaluate the performance of different commercial rangefinders and cameras as well as a long-wavelength infrared (LWIR) stereo vision system developed in this research. The smoke was varied from dense, low temperature smoke to light, high temperature smoke for evaluation in a range of conditions. Through small-scale experiments on eleven different sensors, radar and LWIR cameras outperformed other perception sensors within both smoke environments. A LWIR stereo vision system was developed for rangefinding and compared to radar, LIDAR, and visual stereo vision in large-scale testing, demonstrating the ability of LWIR stereo vision to rangefind in dense smoke when LIDAR and visual stereo vision fail. LWIR stereo vision was further developed for improved rangefinding in fire environments. Intensity misalignment between cameras and stereo image filtering were addressed quantitatively. Tests were performed with approximately isothermal scenes and thermally diverse scenes to select subsystem methods. In addition, the effects of image filtering on feature distortion were assessed. Rangefinding improvements were quantified with comparisons to ground truth data. Improved perception in varying levels of clear and smoke conditions was developed through sensor fusion of LWIR stereo vision and a spinning LIDAR. The data were fused in a multi-resolution 3D voxel domain using evidential theory to model occupied and free space states. A heuristic method was presented to separate significantly attenuated LIDAR returns from low-attenuation returns. Sensor models were developed for both return types and LWIR stereo vision. The fusion system was tested in a range of conditions to demonstrate its ability for improved performance over individual sensor use in fire environments. / Ph. D.
25

Spatialisation du statut hydrique de la vigne sur un bassin versant Méditerranéen par télédétection optique / Spatialising vineyard hydric status within a Mediterraneous catchment derived from optical remote sensing

Galleguillos Torres, Mauricio 10 May 2010 (has links)
Le statut hydrique de la vigne est reconnu comme étant un facteur essentiel dans la production viticole. A l'échelle de la parcelle agricole, les travaux de recherche ont permis de mettre au point différentes méthodes de caractérisation du statut hydrique. Cependant, du fait de leur lourdeur de mise en oeuvre, ces méthodes sont difficilement utilisables à l'échelle de la petite région, alors qu'il existe un fort besoin d'informations sur le statut hydrique à cette échelle. L'objectif principal de ce travail est l'obtention d'un statut hydrique spatialisé en milieu viticole méditerranéen, à l'échelle de la petite région. Le site d'étude est la basse vallée de la Peyne, zone de production viticole de 65 km2, représentative du vignoble méditerranéen. La démarche générale consiste à spatialiser l'évapotranspiration réelle (ETR), choisie comme indicateur du statut hydrique, par l'intermédiaire de deux modèles spatialisées (S-SEBI, Roerink et al., 2000 et WDI, Moran et al., 1994) issus d'images de télédétection dans l'infrarouge thermique (capteur ASTER). Les résultats de ces modèles sont validés par comparaison avec des mesures et des simulations locales de l'ETR. Ces simulations, réalisées en utilisant un modèle de transfert hydriques (HYDRUS-1D, Simunek et al., 1998), représentent une solution de validation originale pour obtenir une ETR locale sur un grand nombre de sites, à un coût expérimental réduit. Une étude de sensibilité permet d'apprécier la robustesse de ces modèles spatialisés vis à vis des conditions expérimentales. Après avoir vérifié que les simulations locales réalisées avec HYDRUS 1-D pouvaient effectivement servir de données de validation, nous montrons que les modèles spatialisés testés permettent d'estimer l'ETR à l'échelle journalière avec une précision satisfaisante, le modèle S-SEBI, pourtant plus empirique, donnant de meilleurs résultats que le modèle WDI (RMSE de 0.8 mm.j-1 et 1.1 mm.j-1 respectivement). Nous montrons que ces approches de spatialisation sont sensibles aux conditions expérimentales considérées (champs d'étude spatial pour le S-SEBI, vitesse du vent pour le WDI). Enfin, les résultats de spatialisation mettent en évidence d'importantes variabilités spatio-temporelles de l'ETR sur la zone d'étude. Les structures spatiales de statut hydrique observées à partir des deux modélisations réalisées sont très similaires et semblent être fortement liées aux caractéristiques pédo-paysagères de la zone d'étude / Vineyard hydric status is recognized as an essential factor for wine-producing. At the field scale, research work allowed to develop different methods for hydric status characterization. However, because of tedious implementation, these methods are useless at the watershed scale, whereas hydric status information at this scale is strongly needed. The main objective of this study is to spatialize vineyard hydric status over a Mediterranean watershed. The study site take place in the basse vallée de la Peyne, a 65 km2 wine-producing area, that is representative of the Mediterranean vineyards. The general procedure to achieve this objective was to spatialize actual evapotranspiration (ET), choose as hydric status indicator, through two spatialized models (S-SEBI Roerink et al., 2000 and WDI, Moran et al., 1994) derived from thermal infrared remote sensing imagery (ASTER sensor). The results of these models were validated by comparison with local ET measurements and simulations. These simulations made by a water transfers model (HYDRUS-1D, Simunek et al., 1998), that represent an original validation method to obtain local ET over an important number of sites, at a minimal experimental cost. A sensibility study allowed to identified the sturdiness of these spatialized models to the experimental conditions. After checking that local ET simulations obtained by the HYDRUS 1-D approach were correctly simulated, we showed that S-SEBI and WDI spatialized model, allowed to estimate ET with satisfactory accuracies. The more empiric S-SEBI model produced better results than the WDI model (RMSE about 0.8 mm.j-1 and 1.1 mm.j-1 respectively). Further, the sensibility study showed that these spatialisation approaches were sensitive to experimental conditions, (spatial extent for S-SEBI and wind speed for WDI). Finally, these spatialisation results depicted for important ET spatio-temporal variability over the Peyne watershed. The spatial patterns retrieved by the two models are similar and seems to be strongly related to pedological and landscape characteristics within the study site.
26

Hand-held Augmented Reality for Facility Maintenance

Liu, Fei January 2016 (has links)
Buildings and public infrastructures are crucial to our societies in that they provide habitations, workplaces, commodities and services indispensible to our daily life. As vital parts of facility management, operations and maintenance (O&M) ensure a facility to continuously function as intended, which take up the longest time in a facility’s life cycle and demand great expense. Therefore, computers and information technology have been actively adopted to automate traditional maintenance methods and processes, making O&M faster and more reliable. Augmented reality (AR) offers a new approach towards human-computer interaction through directly displaying information related to real objects that people are currently perceiving. People’s sensory perceptions are enhanced (augmented) with information of interest naturally without deliberately turning to computers. Hence, AR has been proved to be able to further improve O&M task performance. The research motif of this thesis is user evaluations of AR applications in the context of facility maintenance. The studies look into invisible target designation tasks assisted by developed AR tools in both indoor and outdoor scenarios. The focus is to examine user task performance, which is influenced by both AR system performance and human perceptive, cognitive and motoric factors. Target designation tasks for facility maintenance entail a visualization-interaction dilemma. Two AR systems built upon consumer-level hand-held devices using an off-the-shelf AR software development toolkit are evaluated indoors with two disparate solutions to the dilemma – remote laser pointing and the third person perspective (TPP). In the study with remote laser pointing, the parallax effect associated with AR “X-ray vision” visualization is also an emphasis. A third hand-held AR system developed in this thesis overlays infrared information on façade video, which is evaluated outdoors. Since in an outdoor environment marker-based tracking is less desirable, an infrared/visible image registration method is developed and adopted by the system to align infrared information correctly with the façade in the video. This system relies on the TPP to overcome the aforementioned dilemma.
27

Phénotypage haut débit par imagerie multispectrale au verger : étude du déterminisme génétique de la réponse à la contrainte hydrique d'une population d'hybrides de pommier (Malus x domestica Borkh.). / High-throughput phenotyping by multispectral imagery at orchard : study of genetic determinism of response to water constraint of an apple (Malus x domestica Bork) hybrid population.

Virlet, Nicolas 03 July 2014 (has links)
Dans le contexte des changements climatiques prévisibles et d'une demande évaporative accrue vis à vis des cultures, ce travail de thèse vise à évaluer la variabilité génétique du pommier pour sa réponse à la contrainte hydrique. Cette évaluation est d'un intérêt certain pour l'amélioration future de l'espèce, qu'il s'agisse de mieux tolérer le stress pouvant résulter d'une sécheresse temporaire du sol, ou d'une efficience accrue d'utilisation de l'eau. Les méthodes de phénotypage actuellement disponibles pour l'étude de la réponse à la contrainte hydrique ne permettent pas un haut débit de mesure compatible avec les comparaisons simultanées entre de nombreux individus. En conséquence, ce travail de thèse s'est focalisé sur l'application de l'imagerie multi-spectrale aéroportée comme outil de phénotypage à haut débit en condition de plein champ et sur l'évaluation de sa pertinence pour l'analyse quantitative des réponses à la contrainte hydrique et la recherche des déterminismes génétiques associés. Les essais ont été réalisés sur une population hybride de pommiers (croisement Starkrimson x Granny Smith) âgée de 4 ans au début de l'étude, implantée dans le sud de la France. A partir d'images acquises dans les longueurs d'onde du visible, du proche infrarouge et de l'infrarouge thermique, à une résolution spatiale proche de 30cm, différents indices de végétation et de stress ont été calculés permettant d'apprécier la vigueur des arbres et leur transpiration. La prise en compte, dans des modèles linéaires mixtes, de six dates d'expérimentation, couvrant deux campagnes d'acquisitions, et de régimes d'irrigation différenciés sur la population a permis de mettre en évidence l'héritabilité des indices phénotypiques et conduit à la détection de nombreux QTLs. 18 QTLs se sont révélés indépendants de la date d'acquisition. Pour quatre de ces QTLs, dits adaptatifs, c'est-à-dire exprimés en conditions de stress, un certain nombre de gènes candidats potentiellement impliqués dans les réponses précoces responsables de la régulation stomatique ont été identifiés. / In the context of foreseen climate changes and higher evaporative demand in crops, this PhD work is aiming at assessing the apple tree variability in response to hydric constraints. This could be of great interest for future breeding programs in this species, either in respect to temporary abiotic stress tolerance, or looking at a better water use efficiency. Phenotyping methods presently available for evaluating the plant response to hydric constraints do not allow the high-throughput that could be compatible with simultaneous comparison of a high number of individuals. As a consequence, this thesis focused on the application of airborne multispectral imagery as a tool for high-throughput field phenotyping, and it assessed the relevancy of this method for quantitative analysis of response to drought and further dissection of associated genetic determinisms. Trials were realized on a segregating hybrid apple population (Starkrimson x Granny Smith cross), 4-year old at the beginning of study, installed in the South of France. Images acquired in visible, near infrared and thermal infrared, with a spatial resolution close to 30cm, were the calculation basis of various vegetation and stress indices, allowing estimation of individual tree vigor and transpiration. Linear mixed models taking account of six flight dates, covering two acquisition campaigns and including two contrasted irrigation regimes over the apple population, made it possible to highlight the heritability of phenotypic indices and to perform numerous QTLs mapping. Eighteen QTLs were revealed independently from the acquisition date. Out of this QTLs set, a further analysis on 4 of them, which were adaptative i.e. expressed in stress conditions, allowed first identification of putative candidate genes potentially involved in the early stomatal closure.
28

La vulnérabilité du sapin pectiné (Abies alba Mill.) à la sécheresse en milieu méditerranéen selon les propriétés hydriques du sol / Vulnerability of silver fir (Abies alba Mill.) to drought in Mediterranean mountains according to soil properties

Nourtier, Marie 02 December 2011 (has links)
De nombreux cas de mortalité de Sapin pectiné (Abies alba Mill.) sont constatés en limite sud de son aire de répartition en Provence et semblent être liés aux sécheresses successives de la dernière décennie et à la répartition des propriétés hydriques du sol. L’enjeu est alors de mieux évaluer l’impact du stress hydrique sur le fonctionnement écophysiologique de cette espèce et de pouvoir caractériser et cartographier les zones les plus vulnérables à la sécheresse. Sur le Mont Ventoux, une expérimentation a été mise en place pour suivre pendant 3 ans différents paramètres écophysiologiques impliqués dans le comportement hydrique du Sapin pectiné sur des placettes pour lesquelles les propriétés du sol étaient caractérisées. Sur cette montagne de type karstique, les profondeurs de sols sont très variables et, à l'échelle stationnelle, les taux de mortalité et les intensités de stress hydrique étaient plus élevés sur les sols ayant une réserve hydrique plus importante. De plus, un arrière-effet de la sécheresse de 2009 a été observé réduisant durablement la transpiration de l'année suivante. Une approche par modélisation mécaniste a alors été adoptée en intégrant de nouveaux formalismes sur la dynamique racinaire permettant de prendre en compte cet arrière-effet. Elle a été évaluée sur les différents paramètres impliqués dans le cycle de l'eau et du carbone des arbres et le modèle a été validé sur les dynamiques de transpiration et d’accroissement en largeur de cernes des troncs. Des indices basés sur la mesure de température de surface ont été utilisés pour évaluer la possibilité de détecter le stress hydrique en forêt. Il existe une variabilité résiduelle liée aux facteurs climatiques et à la dimension réduite de la surface de mesure dans la relation entre transpiration et température de surface à l'échelle de l'arbre. A l’échelle du versant, la température de surface a permis d'identifier la répartition spatiale de la durée et de l'intensité du stress hydrique en accord avec la typologie de sol réalisées. La télédétection dans l'infrarouge thermique pourrait ainsi être un outil intéressant pour la gestion forestière. / Many reports of deaths of silver fir (Abies alba Mill.) are mentioned at the southern limit of its limit of distribution in Provence and appear to be related to the successive droughts of the last decade and to the distribution of soil water properties. The aim of the study is then to better assess the impact of water stress on ecophysiological functioning of this species and to characterize and map the areas more vulnerable to drought. On the Mont Ventoux, an experiment was set up to monitor for 3 years ecophysiological parameters involved in the water behaviour of silver fir on plots where soil properties were characterized. On this type of karstic mountain, soils depth is highly variable and, at forest stand scale, mortality rates and intensities of water stress were higher on soils with greater water reserve. In addition, a post-effect of the drought of 2009 was observed by reducing transpiration of the following year. A mechanistic modelling approach was then adopted by integrating new formalisms of root dynamics to take into account this post-effect. It was evaluated on various parameters involved in the water and carbon cycles of trees and the model was validated on the dynamics of transpiration and on annual rings width increment of tree trunks.Indices based on measured surface temperature were used to assess the possibility of detecting water stress in forests. At tree scale, there is a residual variability due to climatic factors and to the small size of the measurement surface in the relationship between transpiration and surface temperature. At the mountainside scale, surface temperature indices allowed identifying the spatial distribution of the duration and intensity of water stress according to the typology of soil done. Remote sensing in the thermal infrared could then be a useful tool for forest management.
29

Land surface temperature and reflectance spectra integration obtained from Landsat on the soil attributes quantification / Integração da temperatura de superfície terrestre e de espectros de reflectância obtidos do Landsat na quantificação de atributos do solo

Sayão, Veridiana Maria 15 September 2017 (has links)
Soil attributes directly influence on its surface temperature. Although there are several studies using soil spectra obtained from satellites, soil evaluation through Land Surface Temperature (LST) is still scarce. The broad availability of satellite thermal data and the development of algorithms to retrieve LST facilitated its use in soil studies. The objective of this study was to evaluate soil LST variations due to its composition and verify the potential of using LST on soil attributes quantification, also integrated with reflectance spectra and elevation data. The study area (198 ha) is located in Sao Paulo state, Brazil, and had plowed bare soil during the satellite image acquisition date. Soil samples were collected in a regular grid of 100 x 100 m (depths: 0-0.2 m and 0.8- 1.0 m); soil granulometry, organic matter (OM) and iron oxides were determined by wet chemistry analysis. In this study, an image of Landsat 5 was used for extracting LST using the inversion of Planck\'s function in band 6 (10,400 - 12,500 nm), and land surface emissivity was estimated using Normalized Difference Vegetation Index threshold method. Reflectance values were extracted from bands 1, 2, 3, 4, 5 and 7. Models for soil attributes quantification were performed using Linear Regression (LR), with samples from 62 auger points distributed in 14 toposequences. Simple LR was applied for generating prediction models based on LST and on elevation data (extracted from a Digital Elevation Model). Multiple LR was applied in order to generate prediction models using atmospherically corrected spectral reflectance from Visible, Near-Infrared and Shortwave infrared (Vis-NIR-SWIR) bands as predictors, and also for the prediction of soil attributes using simultaneously Vis-NIR-SWIR, LST and elevation data, and only significant variables identified by T-tests were used. Predictive performance of models was assessed based on adjusted coefficient of determination (R2adj), Root Mean Squared Error (RMSE, g kg-1) and Ratio of Performance to Interquartile Range (RPIQ) obtained in validation. Ordinary kriging was also performed and the resulted interpolated surfaces were compared to the maps obtained from the best LR model. There was significant correlation between soil attributes and reflectance, LST and elevation data, and soils with clay texture were differentiated from sandy soils based on LST mean values. For all soil attributes, models using only elevation presented the worst performance; models using only LST, moderate performance; and using Vis-NIR-SWIR bands, good predictive performance. For clay, the best model obtained had bands 4-7, LST and elevation as predictors; for sand and iron oxides, the best model had bands 4-7 and LST; for OM, band 4, band 7 and LST. The use of LST for estimating soil attributes increases the predictive performance of multiple LR models when associated with other variables obtained through remote sensing, particularly surface reflectance data, improving the validation of models reaching high R2adj, high RPIQ and low RMSE values. Maps for sand, OM and iron oxides obtained through ordinary kriging outperformed those obtained for the same attributes using LR models based on RS co-variables, and for clay, both approaches reached the same accuracy level. Mapping of soil clay, sand, OM and iron oxides contents through multiple LR models using Landsat 5 products is a simple and easy to reproduce technique, appropriate for soil attributes mapping in bare soil agricultural areas. / Os atributos do solo influenciam diretamente na sua temperatura de superfície. Apesar de existir vários estudos utilizando espectros de solos obtidos de satélite, a avaliação do solo por meio da Temperatura de Superfície Terrestre (em inglês Land Surface Temperature, LST) ainda é escassa. A ampla disponibilidade de dados termais de satélite e o desenvolvimento de algoritmos para derivar a LST facilitou o seu uso em estudos de solos. O objetivo desse trabalho foi avaliar variações da LST do solo devidas à sua composição e verificar o potencial de uso da LST na quantificação de atributos do solo, também integrada com dados de espectros de reflectância e elevação. A área de estudo (198 ha) está localizada no estado de São Paulo, Brasil, e estava com solo exposto e arado na data de aquisição da imagem de satélite. Amostras de solo foram coletadas em um grid regular de 100 x 100 m (profundidades: 0.02 m e 0.8-1.0 m); a granulometria do solo, matéria orgânica (MO) e óxidos de ferro foram determinados via análises físicas e químicas laboratoriais. Neste estudo, uma imagem do Landsat 5 foi utilizada para extrair a temperatura de superfície usando a inversão da função da Lei de Planck na banda 6 (10.400 - 12.500 nm), e a emissividade de superfície foi estimada utilizando o método do limiar do Índice de Vegetação da Diferença Normalizada. Valores de reflectância das bandas 1, 2, 3, 4, 5 e 7 foram extraídos. Modelos para quantificação de atributos do solo foram feitos usando Regressão Linear (RL), com amostras de 62 pontos de tradagem distribuídos em 14 topossequências. A RL simples foi aplicada para gerar modelos de predição baseados na LST e também na elevação (extraída de um modelo digital de elevação). A RL múltipla foi aplicada para gerar modelos de predição usando os espectros de reflectância com correção atmosférica das bandas do Visível, Infravermelho próximo e Infravermelho de ondas curtas (Vis-NIR-SWIR) como preditores; também foi aplicada para predição de atributos do solo usando simultaneamente dados do Vis-NIR-SWIR, LST e elevação, e apenas variáveis significativas identificadas por teste T foram usadas. A performance preditiva dos modelos foi avaliada baseada no coeficiente de determinação ajustado (R2adj), raiz do erro quadrático médio (RMSE, g kg-1) e razão de desempenho do intervalo interquartil (RPIQ) obtidos na validação. A krigagem ordinária também foi feita e as superfícies interpoladas resultantes foram comparadas com o melhor modelo de RL. Houve correlação significativa entre os atributos do solo e dados de reflectância, LST e elevação, e solos com textura argilosa foram diferenciados de solos arenosos com base em valores médios de LST. Para todos os atributos do solo, os modelos usando apenas elevação apresentaram a pior performance, modelos usando somente LST, performance moderada, e usando as bandas do Vis-NIR-SWIR, boa performance preditiva. Para argila, o melhor modelo obtido teve as bandas 4-7, LST e elevação como preditores; para areia e óxidos de ferro, o melhor modelo teve as bandas 4-7 e LST; para MO, banda 4, banda 7 e LST. O uso da LST para estimar atributos do solo aumenta a performance preditiva de modelos de RL múltipla quando associada a outras variáveis obtidas via sensoriamento remoto (SR), particularmente dados de reflectância de superfície, melhorando a validação dos modelos atingindo altos valores de R2adj e RPIQ e baixos valores de RMSE. Os mapas para areia, MO e óxidos de ferro obtidos via krigagem ordinária superaram aqueles obtidos para os mesmos atributos usando modelos de RL baseados em co-variáveis obtidas via SR, e para argila, ambas abordagens atingiram o mesmo nível de acurácia. O mapeamento dos conteúdos de argila, areia, matéria orgânica e óxidos de ferro do solo via modelos de RL múltipla utilizando produtos do Landsat 5 é uma técnica simples e fácil de reproduzir, apropriada para o mapeamento de atributos do solo em áreas de agricultura com solo exposto.
30

Imagerie infrarouge thermique haute résolution : potentiels et limitations pour la géologie / High resolution thermal infrared imaging : potential and limitations for earth sciences

Gaudin, Damien 12 July 2012 (has links)
Le rayonnement infrarouge thermique (7.5-14 μm) permet de mesurer à distance la température de surfaces géologiques. Les capteurs de type “microbolomètre”, de bas prix et d’utilisation facile, sont de plus en plus utilisés pour cartographier sur le terrain des anomalies de température. Cependant, des phénomènes tels que l’opacité de l’atmosphère et les réflexions de la surface viennent modifier le signal. De plus, les images doivent être ajustées géométriquement pour être cartographiées. Après avoir proposé un protocole de correction géométrique et radiométrique des mesures, et quantifié les incertitudes résiduelles, quelques exemples sont étudiés pour définir les potentiels et les limites de l’infrarouge thermique en sciences de la Terre. Son potentiel pour la détection de la ligne de rivage a été utilisé lors d’une marée montante pour reconstituer le modèle numérique de terrain (MNT) d’une plage de l’Aber Benoît (Bretagne). D’autre part, un modèle informatique a été développé pour mesurer l’influence de la rugosité sur la température de la surface des planètes. Il a été appliqué au calcul de l’inertie thermique de Mars et de l’astéroïde (2867) Šteins. Enfin, les images infrarouges sont utilisées pour quantifier le flux de chaleur d’une zone sub-fumerollienne de la Soufrière. Ainsi, l’imagerie thermique infrarouge montre un fort potentiel, partiellement inexploité par les études actuelles, notamment pour la cartographie quantitative des contrastes de température à haute résolution. A haute fréquence, elle permet d’étudier la dynamique des phénomènes géologiques. / Thermal infrared (7.5-14 μm) enables the measurement of temperature far fromgeological surfaces. Microbolometers devices are increasingly used in the field in order to mapthermal anomalies. However, phenomena such as atmospheric opacity and surface reflections disturb the electromagnetic signal. In addition, images have to be geometrically adjusted to fit with geographical models. A processing chain is here suggested in order to correct the radiometry and the geometry of images, and the uncertainties are computed. Then, its potential and limitations are considered, through a few examples. First, it has been used in order to detect the waterline evolution of a mud shore during a rising tide, which enables to reconstruct a digital elevation model. Then, a computer model has been developed to study the roughness effects on the surface temperature and on the thermal inertial calculation on Mars and on the (2867) Šteins asteroid. Finally the heat flux of a sub-fumarolian zone has been computed in La Soufrière volcano (Guadeloupe, Lesser Antilles).Thus, thermal infrared remote sensing is very useful in quantitatively mapping the temperatures anomalies with a high resolution. High frequency studies should enable the survey of geological phenomena.

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