Creation of an anti-imaging system using binary optics

We present a concealing method in which an anti-point spread function (APSF) is generated using binary optics, which produces a large-scale dark area in the focal region that can hide any object located within it. This result is achieved by generating two identical PSFs of opposite signs, one consisting of positive electromagnetic waves from...

Toward nonlinear modeling of meander evolution

Coherence converting plasmonic hole arrays

Simulations are presented that demonstrate that the global state of spatial coherence of an optical wavefield can be altered on transmission through an array of subwavelength-sized holes in a metal plate that supports surface plasmons. It is found that the state of coherence of the emergent field strongly depends on the separation between the...

On the Numerical Rank of the Off-Diagonal Blocks of Schur Complements of Discretized Elliptic PDEs

It is shown that the numerical rank of the off-diagonal blocks of certain Schur complements of matrices that arise from the finite-difference discretization of constant coefficient, elliptic PDEs in two spatial dimensions is bounded by a constant independent of the grid size. Moreover, in three-dimensional problems the Schur complements are...

Counterexample to a Conjecture on an Infeasible Interior-Point Method

In [SIAM J. Optim., 16 (2006), pp. 1110–1136], Roos proved that the devised full-step infeasible algorithm has $O(n)$ worst-case iteration complexity. This complexity bound depends linearly on a parameter $\bar{\kappa}(\zeta)$, which is proved to be less than $\sqrt{2n}$. Based on extensive computational evidence (hundreds of thousands of...

Mobility modeling for personal networks

A Personal Network (PN) is a user-centric design interconnecting numerous devices belonging to a user in different geographic locations, such as home, office, car, etc., to form a single global network to offer fully personalized services. In PNs devices of the user move in different groups, where these groups merge and split. In this paper, we...

Improved Full-Newton Step O(nL) Infeasible Interior-Point Method for Linear Optimization

We present several improvements of the full-Newton step infeasible interior-point method for linear optimization introduced by Roos (SIAM J. Optim. 16(4):1110–1136, 2006). Each main step of the method consists of a feasibility step and several centering steps. We use a more natural feasibility step, which targets the ?+-center of the next pair...

A Survey of Indoor Positioning Systems for Wireless Personal Networks

Recently, indoor positioning systems (IPSs) have been designed to provide location information of persons and devices. The position information enables location-based protocols for user applications. Personal networks (PNs) are designed to meet the users' needs and interconnect users' devices equipped with different communications technologies...

Preliminary study of pur-revetment's application

PUR-revetment is a newly developed method for hydraulic application. Its structure is similar to that of open stone asphalt revetment, but the crushed stones are glued by polyurethane (PUR) instead of bitumen. To study the feasibility of applying PUR-revetment, a research based on the comparisons between PUR-revetment and open stone asphalt...

A Fast Solver for HSS Representations via Sparse Matrices

Some fast algorithms for sequentially semiseparable representations

Efficient and simplified time domain simulation of nonlinear responses of ships in waves