Ray tracing (physics)
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The Sky Is Not the Limit: LTE for Unmanned Aerial Vehicles Open
Many use cases of unmanned aerial vehicles (UAVs) require beyond visual\nline-of-sight (LOS) communications. Mobile networks offer wide area, high\nspeed, and secure wireless connectivity, which can enhance control and safety\nof UAV opera…
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Differentiable Monte Carlo ray tracing through edge sampling Open
Gradient-based methods are becoming increasingly important for computer graphics, machine learning, and computer vision. The ability to compute gradients is crucial to optimization, inverse problems, and deep learning. In rendering, the gr…
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Keyhole-induced porosities in Laser-based Powder Bed Fusion (L-PBF) of Ti6Al4V: High-fidelity modelling and experimental validation Open
Metal additive manufacturing, despite of offering unique capabilities e.g. unlimited design freedom, short manufacturing time, etc., suffers from raft of intrinsic defects. Porosity is of the defects which can badly deteriorate a part’s pe…
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5G 3GPP-Like Channel Models for Outdoor Urban Microcellular and Macrocellular Environments Open
For the development of new 5G systems to operate in bands up to 100 GHz, there is a need for accurate radio propagation models at these bands that currently are not addressed by existing channel models developed for bands below 6 GHz. This…
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Model-Aided Deep Learning Method for Path Loss Prediction in Mobile Communication Systems at 2.6 GHz Open
Accurate channel models are essential to evaluate mobile communication system performance and optimize coverage for existing deployments. The introduction of various transmission frequencies for 5G imposes new challenges for accurate radio…
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Normalizing a relativistic model of X-ray reflection Open
Aims. The only relativistic reflection model that implements a parameter relating the intensity incident on an accretion disk to the observed intensity is relxill. The parameter used in earlier versions of this model, referred to as the re…
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FLIP Open
Image quality measures are becoming increasingly important in the field of computer graphics. For example, there is currently a major focus on generating photorealistic images in real time by combining path tracing with denoising, for whic…
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DeepMIMO: A Generic Deep Learning Dataset for Millimeter Wave and Massive MIMO Applications Open
Machine learning tools are finding interesting applications in millimeter wave (mmWave) and massive MIMO systems. This is mainly thanks to their powerful capabilities in learning unknown models and tackling hard optimization problems. To a…
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Edge Detection and Feature Line Tracing in 3D-Point Clouds by Analyzing Geometric Properties of Neighborhoods Open
This paper presents an automated and effective method for detecting 3D edges and tracing feature lines from 3D-point clouds. This method is named Analysis of Geometric Properties of Neighborhoods (AGPN), and it includes two main steps: edg…
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Shadows and optical appearance of black bounces illuminated by a thin\n accretion disk Open
We study the light rings and shadows of an uniparametric family of\nspherically symmetric geometries interpolating between the Schwarzschild\nsolution, a regular black hole, and a traversable wormhole, and dubbed as black\nbounces, all of …
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Analysis of the Performance Enhancement of MIMO Systems Employing Circular Polarization Open
The advantages of adopting circular polarization in multiple-input-multiple-output (MIMO) systems are illustrated for both line-of-sight (LOS) and multipath propagation. More in detail, an analysis of the MIMO performance attainable by emp…
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Channel Modelling and Performance Limits of Vehicular Visible Light Communication Systems Open
Visible light communication (VLC) has been proposed as an alternative or complementary technology to radio frequency vehicular communications. Front and back vehicle lights can serve as wireless transmitters making VLC a natural vehicular …
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Virtual laser scanning with HELIOS++: A novel take on ray tracing-based simulation of topographic full-waveform 3D laser scanning Open
Topographic laser scanning is a remote sensing method to create detailed 3D point cloud representations of the Earth's surface. Since data acquisition is expensive, simulations can complement real data given certain premises are met: (i) m…
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McStas (i): Introduction, use, and basic principles for ray-tracing simulations Open
We present an overview of, and an introduction to, the general-purpose neutron simulation package McStas. We present the basic principles behind Monte Carlo ray-tracing simulations of neutrons performed in the package and present a few sim…
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Tracing Magnetic Fields with Spectroscopic Channel Maps Open
We identify velocity channel map intensities as a new way to trace magnetic fields in turbulent media. This work makes use of both the modern theory of magnetohydrodynamic (MHD) turbulence, which predicts that magnetic eddies are aligned w…
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Aether Open
Implementing Monte Carlo integration requires significant domain expertise. While simple samplers, such as unidirectional path tracing, are relatively forgiving, more complex algorithms, such as bidirectional path tracing or Metropolis met…
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5G Positioning and Mapping With Diffuse Multipath Open
5G mmWave communication is useful for positioning due to the geometric connection between the propagation channel and the propagation environment. Channel estimation methods can exploit the resulting sparsity to estimate parameters (delay …
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First tomographic observations of gravity waves by the infrared limb imager GLORIA Open
Atmospheric gravity waves are a major cause of uncertainty in atmosphere general circulation models. This uncertainty affects regional climate projections and seasonal weather predictions. Improving the representation of gravity waves in g…
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A Practical Irradiance Model for Bifacial PV Modules Open
A model, suitable for a row or multiple rows of photovoltaic (PV) modules, is presented for estimating the backside irradiance for bifacial PV modules. The model, which includes the effects of shading by the PV rows, is based on the use of…
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Implementation of the toroidal absorption cell with multi-layer patterns by a single ring surface Open
We developed a type of toroidal multi-pass cell with multi-layer patterns based on the off-axis model. The effective path length of the original toroidal multi-pass cell is extended several roundtrips in comparison with the single-layer pa…
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Visible Light Communication Channel Modeling for Underwater Environments With Blocking and Shadowing Open
In this paper, we present a comprehensive channel modeling and characterization study for underwater visible light communications. Our study is based on the advanced ray tracing, which allows for an accurate description of the interaction …
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High-efficient computer-generated integral imaging based on the backward ray-tracing technique and optical reconstruction Open
A high-efficient computer-generated integral imaging (CGII) method is presented based on the backward ray-tracing technique. In traditional CGII methods, the total rendering time is long, because a large number of cameras are established i…
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Macroscopic Modeling of Anomalously Reflecting Metasurfaces: Angular Response and Far-Field Scattering Open
| openaire: EC/H2020/871464/EU//ARIADNE
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Path replay backpropagation Open
Differentiable physically-based rendering has become an indispensable tool for solving inverse problems involving light. Most applications in this area jointly optimize a large set of scene parameters to minimize an objective function, in …
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Underwater Laser Scanner: Ray-Based Model and Calibration Open
Underwater 3-D perception is crucial for autonomous manipulation and mapping. Using a mirror-galvanometer system to steer a laser line projector and using triangulation with a camera it is possible to produce full 3-D perception, while avo…
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TRACER: Extreme Attention Guided Salient Object Tracing Network (Student Abstract) Open
Existing studies on salient object detection (SOD) focus on extracting distinct objects with edge features and aggregating multi-level features to improve SOD performance. However, both performance gain and computational efficiency cannot …
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Semi-Deterministic Radio Channel Modeling Based on Graph Theory and Ray-Tracing Open
Graph theory channel modelling is an efficient approach to simulate multipath radio propagation including the reverberation effect of electromagnetic waves. In this contribution, without modifying the modelling framework, we proposed a sem…
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Acuros<span>CTS</span>: A fast, linear Boltzmann transport equation solver for computed tomography scatter – Part I: Core algorithms and validation Open
Purpose To describe Acuros ® CTS , a new software tool for rapidly and accurately estimating scatter in x‐ray projection images by deterministically solving the linear Boltzmann transport equation ( LBTE ). Methods The LBTE describes the b…
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Path Loss Exponent and Shadowing Factor Prediction From Satellite Images Using Deep Learning Open
Optimal network planning for wireless communication systems requires the detailed knowledge of the channel parameters of the target coverage area. Channel parameters can be estimated through extensive measurements in the environment. Alter…
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Indoor Building Reconstruction from Occluded Point Clouds Using Graph-Cut and Ray-Tracing Open
Despite the increasing demand of updated and detailed indoor models, indoor reconstruction from point clouds is still in an early stage in comparison with the reconstruction of outdoor scenes. Specific challenges are related to the complex…