Jean-Paul Rudant

Université Gustave Eiffel · laboratoire Sciences et Technologies de l'Information Géographique

The coast of Cameroon, located at the bottom of the Gulf of Guinea, is confronted with coastal hazards whose magnitude, distribution, and consequences are currently largely underestimated if not poorly understood. This study aims to fill this gap by proposing an integrated approach to coastal vulnerability assessment, combining simple traditional m...

This study aimed to monitor vegetation using C-band radar data at a sub-daily time step. To this end, radar measurements using tower-mounted antennas with a 15-min time step, along with physiology-related information (sapflow and micrometric dendrometry), were acquired quasi-continuously from March 2020 to December 2021 in an olive orchard located...

La filière anacarde est en pleine expansion au Bénin où elle est entrain de modifier le paysage de la zone. L’objectif de cette étude était d’analyser la dynamique spatio-temporelle des plantations d’anacardier dans la zone soudano-guinéenne du centre du Bénin de 1991 à 2023 tout en essayant de comprendre les différents facteurs qui peuvent engendr...

Ce travail porte sur l’évaluation du potentiel des images multi-temporelles et multi-capteurs (optique et radar) des satellites Sentinel 1 et 2 pour la cartographie de l’occupation du sol et le suivi de l’évolution du trait de côte dans un écosystème tropical sur la période 2015 à 2020. La zone d’étude choisie est l’Estuaire du Cameroun. Cette zone...

The Bay of Bonny, located along the Cameroon coastline, is home to diverse ecosystems. It is under significant pressure from large human activity, but remains very little studied, like much of the Gulf of Guinea. In order to understand its long-term shoreline variations and the role the wave regime plays in the evolution of the coastline, a study w...

Les défis actuels de l'administration forestière ivoirienne sont la reconstitution du couvert forestier du pays à l'horizon 2040 avec un taux de reforestation annuel de 20%. Cette étude propose une méthode de mise en place d'un système de suivi des affectations des terres pour une agriculture intégrée au développement forestier et une gestion durab...

Cette note tente de répondre à de fréquentes questions touchant à la comparaison optique et radar, par exemple : quelles sont les relations formelles existant entre coefficients de diffusion radar et facteurs de réflectance en optique ? Comment les images reflètent elles les coefficients optiques ou radar destinés à caractériser la surface ?

Today, armed conflict affects some twenty countries, covering an area making up 11% of the surface area of the Earth. Any degradation of nature in these areas represents a harmful depletion of the world’s natural heritage. Despite this, environmental issues are neglected during these periods of conflict, considered secondary to the urgency of resto...

La télédétection est un outil particulièrement adapté pour le suivi de l'occupation des sols en général ; il est aussi particulièrement utilisé pour le suivi de la déforestation. De par l'envoi des satellites Sentinel-1 et Sentinel-2 via le programme Copernicus, la communauté dispose maintenant de données gratuites, avec des périodes de revisites t...

Cet article présente quelques illustrations d.applications de données radar polarimétriques (complètes ou partielles) pour le suivi des surfaces terrestres. La première partie est dédiée aux données radar pleinement polarimétriques. Elle est introduite par un rappel théorique présentant leur spécificité. Puis quelques exemples sont présentés, princ...

La période actuelle est caractérisée par une abondance de données radar libres d'accès dont l'utilisation est encouragée et facilitée par les agences spatiales, ces dernières mettant gratuitement à disposition des utilisateurs des logiciels de traitement et d'analyse d'images. Parallèlement, plusieurs sites académiques ou institutionnels proposent...

Climate change is one of the major environmental challenges of 21st century. One of the consequences of climate change is coastal erosion. The Togolese barrier beach is also affected by the phenomenon of coastal erosion. Due to its geographic location between the Atlantic Ocean and the Lake Togo in the south of the Mono transboundary biosphere rese...

In this study, the potential of Sentinel-1 data to seasonally monitor temperate forests was investigated by analyzing radar signatures observed from plots in the Fontainebleau Forest of the Ile de France region, France, for the period extending from March 2015 to January 2016. Radar backscattering coefficients, σ0 and the amplitude of temporal inte...

A time series issued from modern synthetic aperture radar satellite imaging sensors is a huge dataset composed by many hundreds of million pixels when observing large-scale earth structures such as big forests or glaciers. A concise monitoring of these large scale structures for anomaly spotting thus requires loading and analyzing huge spatio/polar...

The sensitivity of the radar signal to the seasonal dynamics in the Sahel region is a considerable asset for monitoring surface parameters including soil moisture. Given the sensitivity of the radar signal to vegetation mass production, roughness and soil moisture, the main problem has been to estimate the contribution of these three parameters to...

The potential of Sentinel-1 radar data for vegetation monitoring is assessed. Both intensity and interferometric products are assessed over temperate forests and agricultural fields.

French: L'étude de la biodiversité des écosystèmes et de leur dynamique est un enjeu majeur de notre siècle de transition climatique. Pour cela, il est nécessaire de réaliser un suivi précis de l'évolution des populations, basé sur une cartographie régulière et à haute résolution pour recueillir des informations à l'échelle des individus étudiés. D...

Les dernières années ont montré l'intérêt croissant de la télédétection basse altitude (TBA) pour l'étude de zones na- turelles. Mais au-delà de la problématique d'accès au milieu, la cartographie de ces zones à grande échelle pose de nombreuses contraintes sur la partie capteurs d'acquisition. En effet, ce sont des milieux difficiles pour les algo...

Pendant sa période de fonctionnement, le satellite lidar ICESat a récolté des données sur la surface de la terre entre 80° et -80° de latitude. Il a permis d’avoir plusieurs points de mesures altimétriques sur le lac Tsimanampetsotsa sur plusieurs campagnes de mesure. Pour chaque campagne, nous avons trouvé que les dispersions des mesures altimétri...

La lutte contre la déforestation constitue aujourd'hui un défi pour la préservation des écosystèmes forestiers. Dans cet article, les données à grande empreinte LiDAR du capteur GLAS (Geoscience Laser Altimeter System) à bord du satellite ICESat (Ice Cloud and Land Elevation Satellite) ont été utilisées pour détecter les trouées dans la forêt class...

article publié en français (p. 2-13), avec un résumé étendu en anglais (p. 14-15), et 3 planches couleur hors-texte (p. 53-54)

In Europe, water levels in wetlands are widely controlled by environmental managers and farmers. However, the influence of these management practices on hydrodynamics and biodiversity remains poorly understood. This study assesses advantages of using radar data from the recently launched Sentinel-1A satellite to monitor hydrological dynamics of the...

The present study focused on the identification of community forest resources of the Lower Mono Valley (BVM), spatial analysis and monitoring of the spatiotemporal dynamics of classes of land use from 1988 to 2016 of the same area. The study in fact used four (4) esa Radar images S-1 chosen according to the seasons of the year (June image "Great ra...

La télédétection spatiale, s'appuyant sur des mesures au sol et combinée aux Systèmes d'Information Géographique (SIG), apporte aujourd'hui une contribution décisive aux diverses questions qui se posent dans le domaine de la gestion des ressources naturelles et de la conservation en particulier. La présente étude a consisté en l’utilisation d’une s...

The recent years have shown a growing interest in low-altitude remote sensing for the study of natural areas. But natural environments lead to many constraints on acquisition sensors, which add to operational and carriers constraints. This article is a feedback on the design of two of these sensors.

This study evaluates the potential of High Resolution Spotlight TerraSAR-X image for forest type discrimination. Emphasis is put on textural analysis accessible with high resolution radar data. Textural attributes are extracted from GLCM matrices, wavelet, and Fourier Transform (i.e. FOTO method). Their contribution for classification is assessed b...

In this paper we propose to simulate SAR radar images that can be acquired by aircraft or satellite. Thiscorresponds to a real problematic, in fact, an airborne radar data acquisition campaign, was conducted in thesouth east of France. We want to estimate the geometric deformations that a digital terrain model can be subjected. By extrapolation, th...

In this paper we propose to simulate SAR radar images that can be acquired by aircraft or satellite. Thiscorresponds to a real problematic, in fact, an airborne radar data acquisition campaign, was conducted in thesouth east of France. We want to estimate the geometric deformations that a digital terrain model can be subjected. By extrapolation, th...

This study aims to evaluate the contribution of textural analysis from high spatial resolution TerraSAR-X images for tropical forests mapping. This study evaluates the potential of the High resolution Spotlight TerraSAR-X image (HS), with a spatial resolution of 0.6 meter in Range and 1.1 meter in Azimuth, for the classification of tropical forest...

This paper illustrates the contribution of spatio-temporal multiresolution spaceborne radar data for the monitoring of land surfaces. More precisely, it illustrates the potential of C-band spaceborne radar data, by using in synergy scatterometer and Synthetic Aperture Radar (SAR) sensors, for the spatio-temporal monitoring of evaporitic processes o...

L’étude de la biodiversité des écosystèmes et de leur dynamique est un enjeu majeur de notre siècle de transition climatique. Pour cela, il est nécessaire de réaliser un suivi précis de l’évolution des populations, basé sur une cartographie régulière et à haute résolution pour recueillir des informations à l’échelle des individus étudiés. On s’inté...

Les dernières années ont montré l’intérêt croissant de la télédétection basse altitude (TBA) pour l’étude de zones naturelles. Mais au-delà de la problématique d’accès au milieu, la cartographie de ces zones à grande échelle pose de nombreuses contraintes sur la partie capteurs d’acquisition. En effet, ce sont des milieux difficiles pour les algori...

We studied population morbidity in three neighborhoods in Libreville (Gabon), selected to represent the city center, the areas bordering the suburbs, and the areas in between. We surveyed 601 households and found that at least one resident was ill in 35% of the households. Malaria remains the leading cause of morbidity in all three districts, follo...

http://spie.org/Documents/ConferencesExhibitions/ERS-ESD13-Abstracts-lr.pdf

This letter presents an analysis of two synthetic aperture radar (SAR) images time series over a Sahelian area, which is located in the Gourma region, Mali. The first one is acquired at the C-band by the Environment Satellite-Advanced SAR sensor in wide swath (WS) mode and the second one at the L-band by the ALOS-Phased Array-type L-band SAR in fin...

Mapping is a fundamental tool in the ecosystems studies. It is usually done by field records, but this method consumes a lot of time and resources. Remote sensing is a complementary tool but still need ground truth certification due to the scale factor. We present in this article a concept, the Extended Ground Truth, that try to keep the advantag...

The erosion affecting the coast of Port-Bouet (Abidjan, Ivory Coast) is a major threat and concern to the economic infrastructure of the Ivorian Refining Company (SIR), the Felix Houphouet Boigny airport international and homes along the coast. In recent years, in order to better understand this scientific accumulation-erosion budget phenomenon, CU...

A new approach has been proposed for radar and optical image fusion. Candidate images for fusion are polarimetric radar images and very high resolution stereoscopic optical images. The fused product is expected to produce more reliable large scale land cover classifications. In the first part of this paper, observation-based state-of-the-art method...

Acquiring 3D very high resolution data in operational conditions is a real challenge in marine coastal areas exploration for environmental, archaeological and defense and security applications. In order to achieve these goals the use of small autonomous robots can be seen as an efficient solution. Because of the complexity of the development of tha...

In this paper, various aspects of remote sensing teaching are presented in 5 master's degree, second year, in which remote sensing training is important , those are master IG Paris-Est France IASIG (Douala Cameroun), DEA IOGA (Tananarive, Madagascar) ERAIFT (Kinsahsa RDCongo), BVT (Museum Paris), In the five cases, remote sensing is just a part of...

This study aims to evaluate the texture analysis of high spatial resolution images for mapping tropical forests. More precisely, it evaluates the potential of TerraSAR-X image, with spatial resolution of 0.5 meter for the classification of tropical forests located in southern Cambodia. In particular, the focus is put on the contribution of the anal...

The erosion affecting the coast of Port-Bouet (Abidjan, Ivory Coast) is a major threat and concern to the economic infrastructure of the Ivorian Refining Company (SIR), the Felix Houphouet Boigny airport international and homes along the coast. In recent years, in order to better understand this scientific accumulation-erosion budget phenomenon, CU...

The study is the production of space maps with the synthetic aperture radar (SAR) images. To achieve this, we proceed by adopting approaches optimized of texture analysis of images, using the statistical parameters of Haralick generalized at the order n. The approach is based on the concept of generic tree. It has the advantage of being less time c...

The present paper is an extension of a previous work presented in (Soheilian et al., 2006a) in which an automatic algorithm of zebra- crossing reconstruction from stereo-pairs of a mobile mapping system was proposed. The method has been adapted to reconstruct different types of rectangular roadmarks. The algorithm can be summarized in three main po...

The traditional method of landsat satellite data combination and the gathering of important information made it possible to produce a Geographical Information System to monitor floods in the lower estuary of the Senegal River valley (Sandholt,I., Fog, B. & Fensholt, R., 2001). This technical approach is a powerful tool for combining important infor...

A new approach has been proposed for radar and optical image fusion. Candidate images for fusion are polarimetric radar images and very high resolution stereoscopic optical images. The fused product is expected to produce more reliable large scale land cover classifications. In the first part of this paper, observation-based state-of-the-art method...

Background and aims - The Lopé National Park in Gabon, recently added to the UNESCO world heritage list, presents a mosaic of forest and savanna that dynamically changes. Conserving this landscape requires an understanding of the forest dynamics. This study aims at defining a forest typology at Lopé in relation with its dynamics. Methods - Floristi...

Classical and modern statistical methods offer a wide variety of approaches to the classification of data in general and classification of imagery in particular. None of these approaches explicitly use spatial information. Spatial covariance structures have been used for data prediction, but not directly for classification. This paper describes a c...

This letter presents a case study addressing the comparison between different synthetic aperture radar (SAR) partial polarimetric options for tropical-vegetation cartography. These options include compact polarization (CP), dual polarization (DP), and alternating polarization (AP). They are all derived from fully polarimetric (FP) SAR data acquired...

Traditional medicine in Libreville is undergoing changes, despite the refusal of some actors in the modern health-care system to recognize it. It is gradually adopting the methods and techniques of modern medicine for patient management. It therefore occupies the same medical space as the modern care system, creating competition. Traditional medici...

RESUME En ce début de 21 e siècle, le risque d'inondation constitue encore le risque majeur au monde (avec les tempêtes, les inondations représentent 60% des catastrophes naturelles) et le réchauffement climatique pourrait encore renforcer ce phénomène à l'avenir. En Europe, malgré toutes les politiques et les mesures prises, au cours des dernières...

: Classical and modern statistical methods offer wide variety approaches of data classification in general and image classification in particular. Among these approaches none of them explicitly use spatial information. Structures with spatial covariance have been used for predicting data, but are not directly use for classifying. This paper deals w...

This paper presents a case study addressing the comparison between different SAR polarimetric mode for tropical forest stratification: Full polarimetry (FP), Dual Polarimetry (DP) and Compact Polarimetry (CP). These 2 latter modes are simulated using FP data acquired by the L band PALSAR sensor over 2 study sites. Cayenne in French Guyana and the F...

One of the most important parameters in the estimation of the evolution of global change is the gas composition of the atmosphere and its temporal variation. Amongst the various and complex processes that absorb or produce gases, the biomass burning has very important short and long term effects [1]. Remote sensing plays a key role in monitoring th...

Radio communication and observation services are critical at all levels of disaster management. Radio communications are essential for sending and distributing alarm messages, exchanging information between different teams/groups [1], defining and coordinating relief activities, and disseminating information and instructions to public and private s...

A specificity of Synthetic Aperture Radar (SAR) scenes is to display geometric distortions depending on both the system of acquisition ant its relation with the topography. Establishing the geometric relationship between the radar sensor parameters and the related surface deformation should therefore provide quantitative information on the topograp...

This paper presents different radar polarimetric modes over different study sites in Tropical environment: Full polarimetry (FP), Dual Polarimetry (DP) and Compact Polarimetry (CP). By using SVM classification, we show the capabilities of each polarimetric mode linked to the scattering model assumption of the fully polarimetric reconstruction for C...

Monitoring vegetation dynamics is a very important task for biodiversity conservation, especially in the Global Change context where many natural habitats are threatened with extinction or reduced to small areas. Remote sensing (aerial or spatial) has played a key role in this monitoring for years. With space imagery, the main limitation is actuall...

ISBN: 978-1-4244-9566-5 - WOS

ISBN: 978-1-4244-9566-5 - WOS

Previous studies, conducted in the urban of Antananarivo, showed low rate of confirmed malaria cases. We used a geographical and environmental approach to investigate the contribution of environmental factors to urban malaria in Antananarivo. Remote sensing data were used to locate rice fields, which were considered to be the principal mosquito bre...

The purpose of this study is to characterise the flooding zone in the lower valley of the Senegal River and to thus contribute to the prevention and monitoring of this natural disaster in the Northern part of the country. This paper explores a new tool which uses remote sensing and isotope hydrology in investigating flooding. It examines flooding i...

Availability and access to primary healthcare facilities is a subject of great concern in African countries south of the Sahara. Problems remain not only in the range of services but also in equality of access. By definition the public health sector has a responsibility to provide citizens with equal access to care facilities. The purpose of this s...

The objective of this paper is twofold: first, to assess the potential of radar data for tropical vegetation cartography and, second, to evaluate the contribution of different polarimetric indicators that can be derived from a fully polarimetric data set. Because of its ability to take numerous and heterogeneous parameters into account, such as the...

Cameroon's coast is a great asset for tourism and the economic recovery of Cameroon. There is a recent population surge towards the coast of Cameroon, which calls for attention to the balance between urban areas and natural areas. It is therefore imperative to promote business development and jobs related to the coasts, coastal waterways and shorel...

In this paper, a new method for computing surface parameters, especially the surface roughness, is presented. This method is designed for easily reconstruct and extract informations from a collection of photos taken without any constraints. This absence of constraints is possible since camera calibration can be computed with bundle adjustment auto-...

In this article, we present another way to acquire centimetric data using a quad-rotor UAV and the specific tools developed to perform near real time cartography. After setting the context of the UAVs, we will present the design and the realization of our quad-rotor Vertical Take Off and Landing solution and it's capacity for Very High Resolution i...

The goal of this study consists in extracting and evaluating the coastline length from a synthetic aperture radar image (SAR) of the ERS-1 satellite, of very big size. In this study, structural approach using variogram is used to characterize the texture from the image. The feature vector obtained by the variographic analysis is used to extract the...

Eager for greater flexibility, and lesser costs, we are often tempted to acquire high-resolution data with home-made acquisition systems. However, this approach cannot benefit from usual tools to tackle problems such as image navigation within a large flow of very high resolution pictures, data completion and image mosaicing of small patches of the...