Measurements of the velocities of galaxies thought to be associated with the giant radio galaxy NGC 6251 confirm the presence of a poor cluster with a systemic redshift of z = 0.0244 ± 0.0004 and a line-of-sight velocity dispersion of σ z = 283 (+109, −52) km s −1. This suggests a cluster atmosphere temperature of T = 0.7 (+0.6, −0.2) keV, which is not enough to confine the radio jet by gas pre...

In this paper, two-dimensional percolation lattices are applied to describe wireless propagation environment, and stochastic rays are employed to model the trajectories of radio waves. We first derive the probability that a stochastic ray undergoes certain number of collisions at a specific spatial location. Three classes of stochastic rays with different constraint conditions are considered: s...

This paper discusses the analysis of multistatic micro-Doppler signatures and related features to distinguish and classify unarmed and potentially armed personnel. The application of radar systems to distinguish different motion types has been previously proposed and this work aims to further investigate the applicability of this in more scenarios. Real data have been collected using a multista...

We suggest that the deceleration of the relativistic shock by a denser part of the interstellar medium off line-of-sight produced the observed radio “flare” in the early afterglow of GRB990123. We find that this scenario is consistent with observations if the particle number density of this denser part of the medium is between ∼ 200 and ∼ 2 × 10 cm. Because of the premature deceleration of part...

We report on mid-infrared imaging of hot cores performed with SpectroCam– 10 and TIMMI2. The observations aimed at the detection of thermal emission presumably associated with the hot cores. Mid-infrared flux measurements are required to improve the luminosity and optical depth estimates for these sources. Results are presented for W3(H2O), G9.62+0.19, G10.47+0.03, and the possible hot core can...

We here introduce an extension and natural generalization of both the κ-μ shadowed and the classical Beckmann fading models: the Fluctuating Beckmann (FB) fading model. This new model considers the clustering of multipath waves on which the line-of-sight (LoS) components randomly fluctuate, together with the effect of in-phase/quadrature power imbalance in the LoS and non-LoS components. Thus, ...

In this paper we will present measurement results that demonstrate the different propagation characteristics of the vertical and horizontal polarizations and their crosscorrelation coupling under line-of-sight and non-line-ofsight conditions. We will also present a simplified model for the propagation environment that uses an approach similar to the method of images, and achieves results that m...

Millimeter-wave (mmWave) communication opens up tens of giga-hertz (GHz) spectrum in the mmWave band for use by next-generation wireless systems, thereby solving the problem of spectrum scarcity. Maintaining connectivity stands out to be a key design challenge for mmWave networks deployed in urban regions due to the blockage effect characterising mmWave propagation. Specifically, mmWave signals...

In this paper a relative attitude determination solution of a formation of two vehicles with multiple constraints is shown. The solution for the relative attitude between the two vehicles is obtained only using line-of-sight measurements between them and common (unknown) objects observed by both vehicles. The constraints used in the solution are formed from triangles on the vector observations....

ÐWe consider the problem of reconstructing the 3D coordinates of a moving point seen from a monocular moving camera, i.e., to reconstruct moving objects from line-of-sight measurements only. The task is feasible only when some constraints are placed on the shape of the trajectory of the moving point. We coin the family of such tasks as atrajectory triangulation.o We investigate the solutions fo...