Comparing reliabilities of centralized and distributed switching architectures for reconfigurable 2D arrays

<span>Whether used as main processing engines or as special-purpose adjuncts, processor arrays are capable of boosting performance for a variety of computation-intensive applications. For large processor arrays, needed to achieve the required performance level in the age of big data, processor malfunctions, resulting in loss of computational capabilities, form a primary concern. There is no shortage of alternative reconfiguration architectures and associated algorithms for building robust processor arrays. However, a commensurately extensive body of knowledge about the reliability modeling aspects of such arrays is lacking. We study differences between 2D arrays with centralized and distributed switching, pointing out the advantages of the latter in terms of reliability, regularity, modularity, and VLSI realizability. Notions of reliability inversion (modeling uncertainties that might lead us to choose a less-reliable system over one with higher reliability) and modelability (system property that makes the derivation of tight reliability bounds possible, thus making reliability inversion much less likely) follow as important byproducts of our study.</span>

Collective Dynamics in Quasi-One-Dimensional Hard Disk System

We present the results of molecular dynamic studies of collective dynamics in a system of hard disks confined to a narrow quasi-one-dimensional (quasi-1D) channel. The computer simulations have been performed for the specific channel width of 3/2 of disk diameter in which the disk arrangement at close packing resembles zigzag ordering characteristic of a vertically oriented two-dimensional (2D) triangular lattice. In such a quasi-1D system, which is intermediate between 1D and 2D arrays of hard disks, the transverse excitations obey very specific dispersion law typical of the usual optical transverse modes. This is in a sharp contrast both to the 1D case, where transverse excitations are not possible, and to the 2D case, where the regular shear waves with a propagation gap were observed. Other peculiarities of the dispersion of collective excitations as well as some results of disk structuring and thermodynamics of the quasi-1D hard disk system are presented and discussed for a range of hard disk densities typical for fluid and distorted crystal states.

Effects of symmetry-breaking on electromagnetic backscattering

Systems with a discrete rotational symmetry $$2\pi /n$$ 2 π / n where $$n\ge 3$$ n ≥ 3 that also have electromagnetic duality symmetry exhibit zero backscattering. The impact of breaking one of the two symmetries on the emerging backscattering has not yet been systematically studied. Here, we investigate the effect that perturbatively breaking each of the two symmetries has on the backscattering off individual objects and 2D arrays. We find that the backscattering off electromagnetically-small prisms increases with the parameters that determine the symmetry breaking, and that the increase of the backscattering due to the progressive breaking of one of the symmetries can be related to the other symmetry. Further exploration of the interplay between the two symmetries reveals that, in systems lacking enough rotational symmetry, the backscattering can be almost-entirely suppressed for a given linear polarization by deliberately breaking the duality symmetry. This duality breaking can be interpreted as an effective increase of the electromagnetic degree of rotational symmetry for that linear polarization.

Self-assembly of colloidal nanoparticles into 2D arrays at water–oil interfaces: rational construction of stable SERS substrates with accessible enhancing surfaces and tailored plasmonic response

Nanoparticle self-assembly at water–oil interfaces has emerged as a convenient and efficient method to construct stable, active and reproducible plasmonic substrates for SERS. In this review we summarize the progress that has been made in this field.