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Events
Most wind-blown sand moves as saltation, in concentrations that decrease at exponential rates away from the surface. The trajectories of saltating grains increase in height and length as their coefficient of restitution increases, as is the case for the smaller particles in a grain population. Conversely, it has been indicated that mean saltation trajectory heights, hs50, increase with mean grain size, d50....
When fermions are in equilibrium with a heat bath they occupy states according to the well-known Fermi-Dirac distribution. When the bath is very cold, this distribution displays a discontinuous jump defining the location of the Fermi surface. But how should fermions occupy states when they are driven away from equilibrium by a time dependent periodic force? would their occupation still have sharp jumps? or would the periodic drive simply heat them up and smear their fermi surfaces?...
Abstract：In this talk, we report some results of quaternion matrices for color image processing:denoising, phase retrieval, and factorization. Numerical examples are presented to show the effectiveness of the proposed quaternion approaches....
Social capital constrains opportunistic behavior and facilitates cooperation in bilateral relationships (Coleman 1988; Guiso 2010). We hypothesize that firms conducting business with high social capital customers are perceived by their banks as having lower supply chain risk and document a negative association between suppliers’ loan spreads and their major customers’social capital. Our cross-sectional analyses show that the negative association is stronger when: (1)suppliers make more significa...
Metasurfaces are ultra-thin metamaterials composed by planar meta-atoms arranged in specific macroscopic orders, which exhibit strong capabilities to control light [1-2]. In this Colloquium, I will present a brief overview on the historical development of this fast-developing research field, focusing particularly on our recent efforts in employing metasurfaces to control light in various aspects....
