Remote Sensing
The performance of a novel ultra-compact Artificial Magnetic Conductor (AMC)-backed Twin Arrow antenna, operative in the 24 GHz frequency band, have been test for an electronic travel aid (ETA) system. Synthetic Aperture Radar (SAR) techniques for high-resolution electromagnetic imaging have been implemented by taking advantage of the natura movement of the user’s body. Experimental measurements for electronic travel aid purposes were conducted by generating electromagnetic images of the surrounding environment. The antenna is moved by means of simple arm swings.
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167 Views
The effect of phase changes along the antenna radiation pattern beamwidth and bandwidth on synthetic aperture radar (SAR) imaging is evaluated by means of electromagnetic simulations. Electromagnetic images have been obtained in order to characterize the effect of the non-uniform phase of the antenna radiation pattern on this type of measurements. Three different situations have been analyzed: i) phase variations across the angular range, ii) nonlinear phase shift across the working frequency band and iii) antenna phase center shift across the bandwidth.
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516 Views
This paper presents a deep learning model for fast and accurate radar detection and pixel-level localization of large concealed metallic weapons on pedestrians walking along a sidewalk. The considered radar is stationary, with a multi-beam antenna operating at 30 GHz with 6 GHz bandwidth. A large modeled data set has been generated by running 2155 2D-FDFD simulations of torso cross sections of persons walking toward the radar in various scenarios.
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10 Views
SAR-optical remote sensing couples are widely exploited for their complementarity for land-cover and crops classifications, image registration, change detections and early warning systems. Nevertheless, most of these applications are performed on flat areas and cannot be generalized to mountainous regions. Indeed, steep slopes are disturbing the range sampling which causes strong distortions in radar acquisitions - namely, foreshortening, shadows and layovers.
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407 Views
Recent advances in Wi-Fi sensing have ushered in a plethora of pervasive applications in home surveillance, remote healthcare, road safety, and home entertainment, among others. Most of the existing works are limited to the activity classification of a single human subject at a given time. Conversely, a more realistic scenario is to achieve simultaneous, multi-subject activity classification. The first key challenge in that context is that the number of classes grows exponentially with the number of subjects and activities.
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788 Views
China has experienced a rapid urbanization over the past three decades, resulting in a prominent “urban core-suburban-rural” (USR) triad structure of human settlements. The USR disparities, which are related to the spatial variations of human activity intensity, have significant impacts on the spatiotemporal variations in various environmental issues such as carbon dioxide (CO2) emissions, carbon storage, water quality, etc. However, there is a lack of national-level, long-term USR dataset compared to the large number of “Urban-Rural” dual structure datasets.
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283 Views
When considering urban growth in metropolitan areas, polycentric urban structures have been significantly observable everywhere, both in developing and developed nations. Morphological urban developments have been considered in many studies, and recently, attention has been paid to polycentric cities. Polycentricism is a collective concept that works at local, regional, and national levels. However, the development of polycentric urban spaces includes a multitude of decentralized morphologies and functional properties that have significant impacts.
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30 Views
Since meteorological satellites can observe the Earth’s atmosphere from a spatial perspective at a large scale, in this paper, a dust storm database is constructed using multi-channel and dust label data from the Fengyun-4A (FY-4A) geosynchronous orbiting satellite, namely, the Large-Scale Dust Storm database based on Satellite Images and Meteorological Reanalysis data (LSDSSIMR), with a temporal resolution of 15 minutes and a spatial resolution of 4 km from March to May of each year during 2020–2022.
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773 Views
Our large scale alpine land cover dataset consists of 229'535 very high-resolution aerial images (50cm) and digital elevation model (50cm) with land cover annotations produced by experts in photo-interpretration . The nine land cover types in our study area include bedrock, bedrock with grass, large blocks, large blocks with grass, scree, scree with grass, water area, forest and glacier. The distribution of pixels among classes presents a typical case of a long-tailed distribution with an imbalance factor, defined as the ratio of the most frequent to the rarest class, close to 1000.
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260 Views
Dataset for validation of a new magnetic field-based wearable breathing sensor (MAG), which uses the movement of the chest wall as a surrogate measure of respiratory activity. Based on the principle of variation in magnetic field strength with the distance from the source, this system explores Hall effect sensing, paired with a permanent magnet, embedded in a chest strap.
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504 Views