Search results for "aerial"

Consequences of forest landscape changes on the availability of winter pastures for reindeer (Rangifer tarandus tarandus) from 1953 to 2003 in Kuusam…

2013

Localization of Multi-Class On-Road and Aerial Targets Using mmWave FMCW Radar

2021

mmWave radars play a vital role in autonomous systems, such as unmanned aerial vehicles (UAVs), unmanned surface vehicles (USVs), ground station control and monitoring systems. The challenging task when using mmWave radars is to estimate the accurate angle of arrival (AoA) of the targets, due to the limited number of receivers. In this paper, we present a novel AoA estimation technique, using mmWave FMCW radars operating in the frequency range 77–81 GHz by utilizing the mechanical rotation. Rotating the radar also increases the field of view in both azimuth and elevation. The proposed method estimates the AoA of the targets, using only a single transmitter and receiver. The measurements are…

Robots, privacy and data protection

2015

A research on robots, drones and privacy/data protection, with focus on cloud robotics, Internet of Things, contracts and the use cases of telepresence, courier robots and smart cities quadricopters.

Evolution des paysages Sahélines au cours des six dernières décennies dans la région de Niamey : de la disparition de la brousse tigrée à l'encroutem…

2010

In the Sahel, the rapid increase of the population during the last decades and the climate variation lead to an important environmental degradation. This work aims to measure the impacts of the human pressure on ecosystem during the six last decades. A diachronic cartography of a 100 km² area close to Niamey was done with aerial photographs (1950 and 1975) and GPS measurements (2009). Results showed that the tiger bush vegetation was completely cleared between 1950 and 2009 while the fallow decreases from 7 % to 1 %. In the sandy valley, the increase of cultivated fields from 20,7 % (1950) to 69,4 % (1975) favoured wind and water erosions which allowed surface soil crusting. Between 1975 an…

Magnetic Prospecting of Diachronic Structures (Antiquity to First World War) on the Site of the Sanctuary of Ribemont-sur-Ancre (Somme, France)

2001

International audience; The site of the sanctuary of Ribemont-sur-Ancre (Somme, France) is of major scientific interest for the knowledge of the Celtic civilization in Europe. It also presents other peculiarities: two clearly identifiable periods of occupation-the first one as early as third century BC-to the second century AD and the second one from 1914-1918. In the area disrupted through military operations, the remains of several epochs are intermingled. In order to obtain a precise knowledge of the space time organisation of each occupation, a magnetic survey was carried out. The comparison of geophysical results with the aerial photographs shot during the war allows an exact determina…

Trajectory Design and Resource Allocation for Multi-UAV Networks : Deep Reinforcement Learning Approaches

2023

The future mobile communication system is expected to provide ubiquitous connectivity and unprecedented services over billions of devices. The unmanned aerial vehicle (UAV), which is prominent in its flexibility and low cost, emerges as a significant network entity to realize such ambitious targets. In this work, novel machine learning-based trajectory design and resource allocation schemes are presented for a multi-UAV communications system. In the considered system, the UAVs act as aerial Base Stations (BSs) and provide ubiquitous coverage. In particular, with the objective to maximize the system utility over all served users, a joint user association, power allocation and trajectory desi…