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The Moroccan coastline, in particular the Atlantic coast, presents a unique geographical and environmental context that requires special attention. Beaches in this region are subject to natural and anthropogenic forces that influence their dynamic evolution. This study focuses on the in-depth analysis and monitoring of Anza beach in Agadir, Morocco. The aim is to provide an in-depth understanding of the evolution of the Anza coastline. Shoreline analysis quantifies shoreline variations and changes over time using the Digital Shoreline Analysis System tool (DSAS). This analysis provides important information on the erosion and accumulation processes that influence the stability of Anza beach.

Bu çalışmanın amacı; RADAR (Results, Approachs, Deploy, Assess And Refine) uygulaması ile örgütsel bağlılık arasındaki ilişkinin araştırılmasıdır. Araştırmanın ana sorunsalı “RADAR uygulamaları ile çalışan bağlılığı arasında nasıl bir ilişki vardır?” şeklinde belirlenmiştir. Çalışmada, araştırmanın amacına ve kapsamına uygun olarak nitel araştırma yöntemi kullanılmıştır. Araştırmada amaca uygun olarak nitel araştırma desenlerinden durum çalışması deseni ve bütüncül tekli durum deseni tercih edilmiştir. Çalışmada, RADAR uygulamalarının örgütsel bağlıkla olumlu bir ilişkisi olduğu ve gerek yöneticiler gerekse çalışanlar düzeyinde örgütsel bağlılığı arttırdığı bulgulanmıştır.

The land-use and land-cover map is fundamental for environmental planning, management, and conservation. Remote sensing data is the information basis for the development of such maps, providing speed and cost-effectiveness. In the Amazon region, the constant presence of cloud cover and smoke makes the use of radar images more adequate for operating independently of these barriers. The present research aims to propose a methodology to classify land use and coverage from PALSAR-2/ALOS-2 multitemporal images in the region of Bananal island. The Bananal island is the second largest fluvial island in the world with approximately 750 km long and 100 km wide. The study area is in the confluence between the Javaés and Araguaia rivers, located in the middle Araguaia river basin. The methodology adopted considers the following steps: acquisition of four multitemporal images Palsar 2/ALOS 2 at processing level 1.5 (L band with resolution of 6.25 meters); (b) Probability Density Component Analysis (PDCA); (c) noise reduction using the Minimum Noise Fraction (MNF) transformation; and (d) classification by the Support Vector Machine method considering the temporal signatures. The ACDP and MNF combination allowed the formulation of different features that describe the different classes present in the image. Comparatively, the images were processed using the Gamma adaptive filter and the SVM classifier. The Kappa coefficient results were 0.62 on the SVM/CDP-MNF images and 0.57 on the SVM / Gamma images. The main factor for the decrease of the Kappa coefficient was the confusion between the areas of Savana Rupestre and anthropic use (pasture) in the areas adjacent to the Bananal island

Last two decades have proven that remote sensing represents a key tool to improve our knowledge of volcanic systems but also to monitor active volcanoes. Based on the specific case of Piton de la Fournaise, Reunion Island, the most active French volcanoes, we here illustrate how Synthetic Aperture Radar (SAR) data, providing information even in cloudy conditions, make it possible to map eruptive deposits, to quantify their volumes but also to estimate the volcanoes topography (with metric precision) as well as surface deformation fields (with a precision reaching a few millimeters). [ABSTRACT FROM AUTHOR]

Remote sensing is a particularly suitable tool for monitoring land use but also particularly suited for déforestation monito-ring. By launching the Setinel-1 and Sentinel-2 satellites in the Copernicus program, the community now has free data with important time-revisits allowing the greatest number of people to effectively monitor land cover of a study area. This paper présents a land use monitoring method based on the combination of two approaches computed using Open Source tools (QGIS, Orfeo ToolBox, python). First, we focus on land use monitoring at an annual time scale using Sentinel-1 and Sentinel-2 data, and then, by the use f entienl-1 data, we detect changes in the forest cover due to déforestation at bi-monthly time scale. The results obtained show a very good synergy of thèse approaches allowing the complementary of optical and radar data. In order to make accessible the proposed method, ail the used open source tools are available on this link http ://remotesensing4all.net/index.php/2018/09/11/kit-use-des-donnees-radar-sentinel-1-in-de-latelier-radar-du-FOSS4G-en-2018-2/. [ABSTRACT FROM AUTHOR]

Due to the weather conditions, airborne and spaceborne radar imagery is an essential source of information for updating the topographic information in the Amazon. This article presents an overview of mapping initiatives in the Amazon using radar techniques in planimetry as well as in altimetry. Instrumental and algorithmic tendencies are described. The challenges of research on radar mapping methods and their applications are discussed. [ABSTRACT FROM AUTHOR]

This article gives some explanations on the technique of interferometry of radar images: how to use it, which products are obtained and what are the constraints to use it. Since its beginnings in the late 1980s, this method, thanks to the multiplication of acquisitions of radar images, the consideration of different types of pixels and the variable image geometries, knows constant progress to make its use more automatic and more efficient. Here we present some of these advances, which allows us to better identify current and future uses. [ABSTRACT FROM AUTHOR]

This article presents some illustrations of (fully or partial) polarimetric radar data applications for the monitoring of terrestrial surfaces. The first part is dedicated to fully polarimetric radar data. Firstly, a theoretical reminder presents the specificity of fully polarimetric data. Then illustrations are given for vegetation types cartography as well as spatio-temporal processes of sedimentation in a semi-arid area in Tunisia. The second part focuses on partially polarimetric data, of the type acquired by the Sentinel-1A/1B satellite SAR sensors, which will be widely used in future years due to their significant contribution to land surface observations studies for environmental sciences. [ABSTRACT FROM AUTHOR]

Les surfaces en herbe jouent un rôle important tant en terme économique qu'environnemental. Elles regroupent une grande diversité de végétation herbacée (pérenne ou éphémère) et occupent une partie importante de l'espace agricole français (zones de pâtures, prairies, milieux agro-naturels présents entre deux cultures principales). Dans ce contexte, cette étude vise à quantifier l'apport de l'imagerie satellitaire multi-spectrale (optique et radar) pour la mise en évidence des surfaces en herbe. Pour ce faire, des classifications supervisées orientées objet, basées sur un algorithme Random Forest et un zonage majoritaire en post-traitement sont utilisées. Cette étude émane de l'expérience de surveillance des cultures multi-capteurs (MCM'10) menée en 2010 sur une zone de polyculture située dans le sud-ouest de la France, à proximité de Toulouse. L'étude s'appuie sur des images satellites acquises entre le 14 et le 18 avril 2010, avec, en radar, des images en bandes X, C et L (de polarisation HH), en optique, une image Formosat-2, et des données terrain concomitantes acquises le 14 avril 2010. Les résultats montrent que la combinaison des images acquises en bande L (Alos) et en optique (Formosat-2) améliore les performances de la classification (précision globale = 0,85 ; Kappa = 0,81) par rapport à l'utilisation des seuls capteurs radar ou optique. Par ailleurs, la performance F-score obtenue pour les surfaces en herbe varie entre 0,1 pour Formosat-2 ; 0,34 pour la combinaison Formosat-2/ Alos et 0,52 pour Alos. Ainsi, les résultats montrent que la qualité de la classification des surfaces en herbe augmente avec l'augmentation de la longueur d'onde des images utilisées.

Les surfaces en herbe jouent un rôle important tant en terme économique qu'environnemental. Elles regroupent une grande diversité de végétation herbacée (pérenne ou éphémère) et occupent une partie importante de l'espace agricole français (zones de pâtures, prairies, milieux agro-naturels présents entre deux cultures principales). Dans ce contexte, cette étude vise à quantifier l'apport de l'imagerie satellitaire multi-spectrale (optique et radar) pour la mise en évidence des surfaces en herbe.Pour ce faire, des classifications supervisées orientées objet, basées sur un algorithme Random Forest et un zonage majoritaire en post-traitement sont utilisées. Cette étude émane de l'expérience de surveillance des cultures multi-capteurs (MCM'10) menée en 2010 sur une zone de polyculture située dans le sud-ouest de la France, à proximité de Toulouse. L'étude s'appuie sur des images satellites acquises entre le 14 et le 18 avril 2010, avec, en radar, des images en bandes X, C et L (de polarisation HH), en optique, une image Formosat-2, et des données terrain concomitantes acquises le 14 avril 2010. Les résultats montrent que la combinaison des images acquises en bande L (Alos) et en optique (Formosat-2) améliore les performances de la classification (précision globale = 0,85 ; Kappa = 0,81) par rapport à l'utilisation des seuls capteurs radar ou optique. Par ailleurs, la performance F-score obtenue pour les surfaces en herbe varie entre 0,1 pour Formosat-2 ; 0,34 pour la combinaison Formosat-2/ Alos et 0,52 pour Alos. Ainsi, les résultats montrent que la qualité de la classification des surfaces en herbe augmente avec l'augmentation de la longueur d'onde des images utilisées. [ABSTRACT FROM AUTHOR]

This paper presents a new concept of aircraft tracking based on a LEO constellation of small satellites, each of them carrying receiving and transmitting devices in order to check the integrity of the ADS-B (Automatic Dependent Surveillance - Broadcast) positioning information and proceed with a non-cooperative independent localization of the aircraft, if a flight anomaly comes out. To do so, on side of the conventional ADS-B processing, authors propose to add a multilateration process and two active radar modes, able to perform a finer and reliable localization of the aircraft, as well as a first information on the nature of the flight anomaly. The paper deals with a preliminary system analysis, although underpinned by some illustrations of existing sensor technologies, already or nearly operational in space. The concept has been patented [1].

Este artículo habla de la experiencia de Thomas Kuhn como físico: su educación en la disciplina, su servicio como experto durante la Segunda Guerra Mundial, y su investigación doctoral. Estudiamos un lapso de tiempo que va de 1940 a 1951. El objetivo en última instancia es ofrecer base empírica para valorar una afirmación como la de Mara Beller (1999), que dice que la descripción kuhniana de la ciencia normal está parcialmente basada en circunstancias y experiencias personales, no sólo en los datos históricos o en la evidencia disponible de la sociología de la ciencia. En este artículo se establece que dicha tesis es plausible.

L'imagerie radar est un moyen actif permettant d'observer le territoire par tout temps indépendamment de toutes conditions météorologiques. L'image radar d'amplitude apporte, à partir de la radiométrie, des informations sur les caractéristiques diélectriques (humidité du sol, cibles métalliques, ...) et géométriques (pente locale, rugosité, orientation, ...) de la surface imagée. Les images diachroniques (composition colorée) sont le résultat d'une comparaison entre des images d'amplitude permettant d'avoir des informations du changement de la radiométrie entre différentes dates. Le MNA (Modèle Numérique d'Altitude) représente une donnée complémentaire importante pour l'analyse du territoire. L'association des deux informations (relief à partir du MNA et images amplitudes avec leurs produits dérivés), permet alors d'avoir une meilleure interprétation de l'évolution du paysage dans la région. L'objectif de notre travail consiste à confronter ces deux informations pour interpréter les changements entre plusieurs dates d'acquisition des images d'amplitude radar (RSO) dans la région de Buzau (Roumanie), région très complexe, très humide et caractérisée par des reliefs et des terrains très accidentés avec différentes pentes ainsi qu'une végétation prépondérante. Ces trois caractéristiques rendent le problème plus complexe car ils compliquent l'interprétation du signal électromagnétique rétrodiffusé. Nous avons pu obtenir différents résultats : (1) La réalisation des images d'amplitude et diachroniques avec une résolution de 20 m sur la période 1995 - 2005. Nous avons produit 12 couples de composition colorée de différents intervalles des satellites ERS et ENVISAT, 6 couples des images ERS entre 1995 et 1999 et 6 couples des images ENVISAT entre 2004 et 2005. (2) La réalisation d'un modèle numérique d'altitude (MNA-ERS1/2-95) de la zone d'étude avec une résolution de 20 m sur une étendue de 100 km x 100 km et une précision globale de moins de 17m. La réalisation du MNA de Buzau est obtenue à partir du couple tandem (ERS-1/ERS-2) des 28 et 29 mai 1995. L'association des images diachroniques d'amplitude avec le MNA-ERS1/2-95 nous a permis d'observer les changements de paysage. Ces changements de paysage ont des origines différentes à cause des trois types du terrain : (a) pour la partie plate (plaines), les changements sont dus à : (i) l'humidité -pluies- (périodes humides et périodes sèches); (ii) culture de champs (rugosité : l'intervalle de temps dépasse les 4 semaines); (iii) la végétation. (b) pour la partie intermédiaire (reliefs modérés, pentes orientées vers le radar), les changements sont dus aux : (i) différence de l'humidité et la végétation; (ii) petites différences d'angle d'incidence entre les différentes prises de vue surtout pour les pentes orientées vers la visée du capteur. (c) pour la partie haute à l'ouest (forts reliefs, reliefs accidentés), les changements sont dus aux : (i) petites distorsions qui sont dues aux différentes géométries d'acquisitions des images (prises de vues); (ii) l'humidité et la végétation. Cette association entre un MNA et des images de composition colorée (radiométrie) ne demande pas une grande précision altimétrique. Par contre, elle demande une plus grande résolution planimétrique. Ces résultats permettent de souligner les points suivants : (1) L'image radar d'amplitude, représente mieux la surface plate (plaine de Buzau) que la surface accidentée (collines subcarpatiques et Carpates). (2) Elle donne pour la région haute des distorsions qui sont proportionnelles aux degrés des pentes. Plus la pente est raide plus la distorsion est grande. (3) Par contre, sur la zone des plaines de Buzau, la distorsion est moins importante sauf pour la distorsion qui résulte des dimensions de résolution qui n'est pas exactement identique dans les deux directions. [ABSTRACT FROM AUTHOR]

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduces the distortion factor inherent in the spectrum estimation of ocean surfaces. Use of radar to scan the ocean surface; Distortion of radar systems by the rotation motion of radar antenna; Application of exact mathematical expression to allow for a detailed analysis of the influence of this distortion on the frequency characteristics.

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Les auteurs décrivent une architecture parallèle rapide, de type statique, à commande dirigée par les données. Cette architecture à structure cellulaire, régulière et facile à intégrer constitue la base d'un opérateur de Riccati rapide ( Orr) destiné à résoudre l'équation matricielle de Riccati. Afin d'évaluer les performances de cet opérateur, deux algorithmes de résolution, Lindquist et quasilinéarisation, ont été représentés par des réseaux de Pétri à flux de données, définis dans ce but, puis simulés. Les résultats de cette simulation ont été comparés aux besoins réels dans le cas de veille et de poursuite radar. The authors describe a fast, parallel and static data flow architecture that is used for Fast Riccati Operator ( Fro) design. This operator has a cellular, regular structure easy to integrate, and is intended to resolve with high speed execution the matrix Riccati equation for filtering purpose. To evaluate its performances, two solving algorithms, Lindquist and quasilinéarisation, are represented and simulated by data flow Petri nets, defined for this purpose. Simulation results are compared to real needs in search and tracking situations. [ABSTRACT FROM AUTHOR]

En détection active (radar, sonar, géophysique, etc.), on cherche à extraire du bruit un signal connu à l'émission mais qui a été réfléchi sur une cible. En raison du caractère généralement aléatoire de cette réflexion, le signal reçu n'est donc pas déterministe ce qui entraîne que, même en présence de bruit gaussien, le récepteur optimal n'est plus le filtre adapté. En introduisant quelques hypothèses statistiques sur la réflexion aléatoire, on définit un modèle statistique du signal reçu qui, en bruit additif gaussien, permet l'expression du rapport de vraisemblance. Le récepteur optimal comporte toujours le filtre adapté au signal émis, observé continûment, suivi d'un dispositif non linéaire, développable sous forme de série, et d'une intégration temporelle. Dans le cas de signaux à faible ambiguïté temporelle, la non-linéarité est instantanée ; sous l'hypothèse d'un faible rapport signal sur bruit, elle se limite aux termes linéaire et quadratique de la série. In active signal detection (e.g., radar, sonar, geophysics, etc.), the objective is to extract in the presence of background noise a signal which is known at the transmission but randomly reflected by the target. The received signal is, therefore, no longer deterministic, and the optimum receiver is not a simple matched filter even if the noise is white Gaussian. By introducing appropriate probability distributions for the random reflection, the authors make a mathematical model of the received signal and calculate the likelihood ratio for the Gaussiannoise case. The optimum receiver consists of the matched filter followed by a nonlinear device, which can be represented by a series of filters, and a time-integrator. In a special case of impulse-like signals, the nonlinearity is virtually memoryless. In the case of low signal-to-noise ratio, the series can be approximated by the first two terms, namely, the linear and the quadratic filters. [ABSTRACT FROM AUTHOR]

Le modèle des points brillants, utilisé en radar pour représenter des cibles complexes telles que des avions, conduit parfois à des résultats décevants qui s'expliquent par une réduction de la cible à un ensemble limité de points de réflexion spéculaire, en négligeant les points de diffraction liés aux discontinuités et les contributions des réflexions multiples. Une première partie rappelle les principes de modélisation des cibles de radar par des points brillants, décrit une méthode simple de mise en évidence expérimentale de ces points par analogie optique et traite le problème des réflexions multiples; une nouvelle loi de composition, valable aux fréquences élevées, tient compte des images par double réflexion. La deuxième partie applique cette méthode à une structure de référence constituée de deux sphères parfaitement conductrices, présente des résultats expérimentaux, propose une modélisation du couplage par double réflexion. The discrete scatterers model used to represent complex radar targets, such as aircraft, sometimes leads to disappointing results which can generally be explained by a reduction of the target to a limited group of specular points: the scattering points linked to discontinuities and the contributions made by multiple reflections are often neglected. A first part recalls the principles of the modelization using discrete scatterers, gives a simple method of displaying experimentally these points by optical analogy, and solves the problem of multiple reflections; a new law of composition, fit for use at high frequencies, takes into account images caused by double reflections. The second part applies this method to a reference structure made up of two perfectly conducting spheres, gives experimental results, and propounds a simple modelization of coupling by double reflection. [ABSTRACT FROM AUTHOR]

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT: Carajás Mineral Province, Amazon region, is the most important one in Brazil. Vale S.A. Company has the right to operate in the area of the N5E mine. The work is conducted on rock alteration products of low geomechanical quality related to sandstones, siltstones, and a lateritic cover. In order to monitor ground deformation, 33 TerraSAR-X images covering the period of March 2012-April 2013 were used in the investigation. An interferometric synthetic aperture radar (InSAR) approach based on permanent scatterer interferometry (PSI) using an interferometric point target analysis algorithm was applied. Results demonstrated that most of the area was considered stable during the time span of the image acquisition. However, persistent scatterers (PSs) with high deformation rates were mapped over a landfill probably related to settlements. To validate the PSI data, graphs were generated with the displaced information based on topographic measurements in the field. The graphs showed that the surface deformations during TSX-1 runway coverage are within the miner’s safety threshold and do not present a risk of major problems. The PSI data provided a synoptic and detailed view of the deformation process that affects the mining complex without the need of field campaign or instrumentation.

The land-use and land-cover map is fundamental for environmental planning, management, and conservation. Remote sensing data is the information basis for the development of such maps, providing speed and cost-effectiveness. In the Amazon region, the constant presence of cloud cover and smoke makes the use of radar images more adequate for operating independently of these barriers. The present research aims to propose a methodology to classify land use and coverage from PALSAR-2/ALOS-2 multitemporal images in the region of Bananal island. The Bananal island is the second largest fluvial island in the world with approximately 750 km long and 100 km wide. The study area is in the confluence between the Javaés and Araguaia rivers, located in the middle Araguaia river basin. The methodology adopted considers the following steps: acquisition of four multitemporal images Palsar 2/ALOS 2 at processing level 1.5 (L band with resolution of 6.25 meters); (b) Probability Density Component Analysis (PDCA); (c) noise reduction using the Minimum Noise Fraction (MNF) transformation; and (d) classification by the Support Vector Machine method considering the temporal signatures. The ACDP and MNF combination allowed the formulation of different features that describe the different classes present in the image. Comparatively, the images were processed using the Gamma adaptive filter and the SVM classifier. The Kappa coefficient results were 0.62 on the SVM/CDP-MNF images and 0.57 on the SVM / Gamma images. The main factor for the decrease of the Kappa coefficient was the confusion between the areas of Savana Rupestre and anthropic use (pasture) in the areas adjacent to the Bananal island

The increasing applications of microwaves, mainly in mobile phones and radar, induce a higher rate of exposed people, sometimes cause of worry. Eyeballs are hotspots of radiofrequency field radiation because of their anatomy and composition. We propose a review of the various effects on the eye. The studies are hardly comparable because the exposure systems, power densities and dosimetries are different. While the thermal effects on the eye are well known including cataracts, corneal edema, endothelial cell loss and retinal degeneration, the non-thermal effects are still controversial. Cell cycle abnormalities, early apoptosis were reported in experimental conditions likely due to oxidative stress, but the studies could not show any significant effect on human eyes when exposed to long-term and low-dose radiation. Next studies need to be closer to human exposure.