16 research outputs found
REFLEXÕES METODOLÓGICAS SOBRE A UTLIZAÇÃO DOS ÍNDICES GEOMÉTRICOS E TOPOLÓGICOS NA ANÁLISE ESPACIAL DE CLASSIFICAÇÕES DE IMAGENS LANDSAT, ESTUDO DE CASO APLICADO AO MUNICÍPIO DE UBATUBA,SP, BRASIL
The new geography, appeared in the years 1960, directed research towards the quantified and quantifiable phenomena. The space analysis allow describing and quantifying the space properties of an area. Its objective is to show that the analysis of these properties is relevant to understand the characteristics of an area. It is based on two types of measurements, forms which concern geometry and the space relations between objects, which concern topology. The município of Ubatuba is the experimental site. The visual interpretation of the thematical charts from classifications of satellite image is not sufficient to analyse the space dynamics. Several geometrical and topological indices were used on the urban spot. These indices reveal the complexity of the forms, aggregation, connection and diversities of the urban spots. Although they indicate the structure and the geometry of the spots, only a contextual interpretation reveal the functional characteristics of the landscape. This interpretation shows the existence of a pioneer front of occupation in Ubatuba.
Key-words: spatial analysis; space index; geographical object; remote sensing; urban areas.A nova geografia, que surgiu nos anos 1960, orientou pesquisas sobre fenômenos quantificáveis e, portanto, quantificados. Surgida desse movimento, a análise espacial permite descrever e quantificar as propriedades espaciais de uma área. Ela se baseia em dois tipos de medidas, a das formas que revelam a geometria, e a das relações espaciais entre os objetos que revelam a topologia. O município de Ubatuba, SP, é o sítio experimental. A análise das cartas temáticas originadas de classificações de imagens de satélite não é suficiente para o estudo da dinâmica espacial. Por isso, diferentes índices geométricos e topológicos foram aplicados sobre a mancha urbana. Esses índices revelam a complexidade das formas, a agregação, a conexão e a diversidade das manchas urbanas. Apesar de indicarem a estrutura e a geometria das manchas, somente a interpretação contextual revela as características funcionais da paisagem. Essa interpretação revelou para Ubatuba a existência de uma frente pioneira de ocupação.
Palavras-chave: análise espacial; índices espaciais; objeto geográfico; sensoriamento remoto; áreas urbanas
Utilisation de données SPOT5 pour la cartographie des habitats benthiques littoraux. Application à l’archipel des îles Chausey (golfe normand-breton, France)
Cette étude présente l’intérêt et les limites des données de télédétection à Haute Résolution Spatiale issues du capteur SPOT5 pour la cartographie des habitats benthiques médiolittoraux. Le site d’étude, l’archipel des îles Chausey (golfe normand-breton, France) se caractérise par un très vaste estran parsemé d’une multitude d’îlots. Par ses contraintes physiques, il constitue un site de recherche privilégié pour répondre aux problèmes actuels de cartographies des habitats littoraux, par ailleurs en cours de réalisation (programme REBENT-IFREMER) et initiées par les instances publiques (services délocalisés de l’État) suite aux nombreuses pollutions côtières. Des méthodes de traitement d’images traditionnelles et couramment utilisées ont été testées et validées à l’échelle de l’archipel par des photographies aériennes récentes et des campagnes d’échantillonnages faites sur le terrain. La classification retenue est très proche de celle de la nomenclature NATURA 2000 en ce qui concerne les habitats naturels de l’estran. Les traitements apportés permettent d’explorer quelques potentialités de SPOT5 et d’afficher ainsi une première évaluation de ces données pour la caractérisation, l’inventaire et le suivi des habitats naturels littoraux.Recent coastal pollutions have induced local and national authorities (research institutes – IFREMER, CNES, IFEN –, decentralised state agencies) to evaluate present mapping techniques and to assess their ability to map coastal benthic habitats. Within these research programs a test site has been choosen to evaluate data from the High Spatial Resolution Satelite SPOT5. It is the Chausey archipelago, in the English Channel which is characterized by a very wide macro tidal shore line with many skerries and very small islands. Such a rugged inter-and sub-tidal topography makes it a very demanding site for cartography. SPOT5 data has been classified (using usual routines of image processing), compared to photos, cross checked with field evidences. This has allowed to point out SPOT5 potential : the classification is very similar to the Natura 2000 check list and shows a good ability to map this type of shore. This preliminary test is a begining to a wider program of coastal monitoring by SPOT5
Geo-archaeological aspectsi in Modena plain, northern Italy
This abstract traces the various stages of geomorphological evolution of the plain area around Modena from the VI millennium B.C. to the Present, through reconstruction of the ancient landscape and human settlements.Geomorphological investigations have led to the implementation of a Micro-relief Map, a Digital Elevation Model (DEM), a Map of surface deposits and a Geomorphological Map.As regards archaeological studies, it was possible to connect archaeological findings with geomorphological surface evidence with a good level of precision. The topographic and stratigraphic positions of archaeological finds have been compared with paleoenvironmental data, in order to reconstruct the evolution of the territory.The comparison of geomorphological and archaeological data allowed many fluvial forms to be dated. In particular, it was interesting to observe the westward shift of the River Panaro from the Bronze Age and the connection of many sites of this period with the fluvial forms identified. In addition, in the area of the historical centre of Modena it was possible to reconstruct the ancient soil levels, starting from Roman times, and measure the thickness of archaeological stratigraphies and alluvial deposition layers. This led to a model of fluvial evolution which shows the aggradation of the plain where the watercourses turn from deepened riverbeds to hanging riverbeds
P23.1 Using non-invasive brain stimulation to provoke modulatory effects on heat induced perception and pain threshold: application of a Bluetooth® interfaced stimulator
Introduction: Transcranial stimulation (magnetic and direct current) is able to change cortical excitability of the motor cortex. In case of chronic pain, modulatory effects have been demonstrated by using brain stimulation, and the mechanism is speculated to be plasticity changes. Objective: The aim of this study was to demonstrate the effect of transcranial direct current stimulation (tDCS) using a Bluetooth® controlled stimulator to modulate pain and perception thresholds to heat stimuli. Methods: In ten healthy controls anodal or sham tDCS was applied to the right primary motor cortex (M1) of the hand. We tested the threshold of heat induced perception and pain when applying heat to the cutaneous area of the superficial radial nerve of the contralateral and ipsilateral (control) hand. Furthermore, we tested cortical excitability using transcranial magnetic stimulation (TMS). Results: We found a significant threshold increase of heat induced perception (15%) and pain (5%) on the contralateral hand. There were no significant effects on the ipsilateral hand, nor for sham stimulation. The effect of tDCS applied for 10 min lasted for about 1 hour. By using TMS applied to the right M1, before and after 10 min of anodal tDCS, we found a significant increase of the motor evoked potentials (MEP) amplitude on the contralateral hand. When TMS was applied to the left M1, no significant changes were observed. Conclusions: The tDCS stimulator was able to modulate perception and pain thresholds, and might be a useful instrument for pain therapy. The effect of tDCS causes transitory brain plasticity and might be due to different mechanisms, such as increased cortical excitability, increased firing rate of neurons, physiological effect on the membrane resting potential, decreased muscle pain related to fatigue, or changes of the brain-derived neurotrophic factor (BDNF). However, further studies must be performed in order to understand the mechanisms of effect on chronic pain
Cartographie morpho-sédimentaire et des habitats benthiques de l'archipel de Chausey à partir de données satellitales, aéroportées et acoustiques.
International audienceL'archipel des Chausey, situé dans le golfe normand-breton, fait l'objet depuis 2002 d'un vaste programme de cartographie de son estran pour répondre à la demande des gestionnaires en matière d'inventaire des habitats benthiques. Cet archipel est inscrit à l'inventaire ZNIEFF et fait l'objet, dans le cadre de la directive européenne "habitats", d'un recensement des milieux naturels d'intérêt européen. Ce travail permet aussi de répondre à certaines problématiques abordées dans le volet littoral "eaux côtières et eaux de transitions" de la directive cadre sur l'eau et d'anticiper la prochaine extension du programme REBENT aux eaux normandes. Outre un important travail de terrain, trois sources de données ont été utilisées pour établir les cartes des habitats benthiques, des figures et des faciès sédimentaires: une image SPOT5 à 2.5 m de résolution, des photographies aériennes au 1:10.000, et des images acoustiques acquises par un sonar latéral. L'ensemble de ces données a été inséré dans un Système d'Information à Références Spatiales compatible avec celui du REBENT Bretagne. La méthodologie et la typologie utilisées sont similaires avec celles du REBENT ; seule l'échelle de numérisation diffère. En effet, les objets ont tous été cartographiés à l'échelle du 1:1000 à l'exception des ceintures algales et des banquettes à lanices issues des classifications de l'image SPOT5. Certaines informations spatiales, dont la carte des herbiers de zostères, sont déjà utilisées dans le cadre de l'intégration géomatique des données biologiques du système MAXSEA embarqué à bord des unités de navigation à fin d'optimisation des prises de pêche liées aux arts traînants
Morpho-sedimentary and benthic habitats mapping of Chausey archipelago from remote sensing, airborne and acoustic data.
National audienc