We study the "hybrid" heterostructure formed by one sheet of single-layer graphene (SLG) and one sheet of bilayer graphene (BLG) separated by a thin film of dielectric material. In general, it is expected that interlayer interactions can drive the system to a spontaneously broken-symmetry state characterized by interlayer phase coherence. The peculiarity of the SLG-BLG heterostructure is that t...

Synthetic aperture radar (SAR) tomography is a powerful approach to investigate the relationship between 3-D radar backscattering and physical structure of agricultural vegetation, which is not fully understood yet. In this paper, the focus is set on the characterization of polarimetric scattering and propagation effects within the vegetation layer as a function of species, time and frequency. ...

A method for the elimination of cracks in infrared reflectograms is presented. Infrared reflectograms show the underdrawing – the basic concept of the artist drawn on the ground layer – in ancient wood panel paintings. Caused by different mechanical behaviour of the panel and the covering ground layer during the aging of the painting, cracks appear. Cracks not only disturb the appearance of a p...

Wildfire is a major disturbance in the Arctic tundra and boreal forests, having a significant impact on soil hydrology, carbon cycling, and permafrost dynamics. This study explores the use of the microwave Interferometric Synthetic Aperture Radar (InSAR) technique to map and quantify ground surface subsidence caused by the Anaktuvuk River fire on the North Slope of Alaska. We detected an increa...

Base-detail separation is a fundamental computer vision problem consisting of modeling a smooth base layer with the coarse structures, and a detail layer containing the texture-like structures. One of the challenges of estimating the base is to preserve sharp boundaries between objects or parts to avoid halo artifacts. Many methods have been proposed to address this problem, but there is no gro...

The purpose of this paper is to study the relationship between columnar aerosol optical thickness and ground-level aerosol mass. A set of Sun photometer, elastic backscattering lidar and TEOM measurements were acquired during April 2007 in Lille, France. The PM2.5 in the mixed boundary layer is estimated using the lidar signal, aerosol optical thickness, or columnar integrated Sun photometer si...

We study the local geometry of a one-hidden-layer fully-connected neural network where the training samples are generated from a multi-neuron logistic regression model. We prove that under Gaussian input, the empirical risk function employing quadratic loss exhibits strong convexity and smoothness uniformly in a local neighborhood of the ground truth, for a class of smooth activation functions ...

In this study, the correlation existing among grinding, surface integrity, and flexural strength is investigated for WC-Co cemented carbides (hardmetals). A fine-grained WC-13 wt % Co grade and three different surface conditions: (1) ground, (2) mirror-like polished (reference), and (3) ground plus high-temperature annealed, are investigated. Surface integrity and mechanical characterization is...

A two-dimensional (2-D) finite-difference model for elastic waves in the ground has been developed. The model uses the equation of motion and the stress-strain relation, from which a first-order stress-velocity formulation is obtained. The resulting system of equations is discretized using centered finite-differences. A perfectly matched layer surrounds the discretized solution space and absorb...

Main atmospheric parameters characterizing the turbulence were measured at the Paranal ESO Observatory (Chile) with the Generalized Seeing Monitor (GSM) during 19 nights in November–December 1998. The median seeing for this period was 0.88′′, a little worse than average, the spatial coherence outer scale of the wavefront L0 = 22.0 m and the median isoplanatic angle θ0 = 1.90′′. A very good agre...