Efficient computation of minimum-variance wave-front reconstructors with sparse matrix techniques.

Appendix 4.6.b Efficient Computation of Minimum Variance Wavefront Reconstructors Using Sparse Matrix Techniques

Minimum variance guided wave imaging in a quasi-isotropic composite plate

Ultrasonic guided waves are capable of rapidly interrogating large, plate-like structures for both nondestructive evaluation and structural health monitoring (SHM) applications. Distributed sparse arrays of inexpensive piezoelectric transducers offer a cost-effective way to automate the interrogation process. However, the sparse nature of the array limits the amount of information available for...

Ultrasonic guided wave imaging for damage characterization

Guided wave imaging with a sparse array of inexpensive transducers offers a fast, reliable, and cost-efficient means for damage detection and localization in plate-like structures such as aircraft and spacecraft skins. As such, this technology is a natural choice for inclusion in condition-based maintenance and integrated structural health management programs. One of the implementation challeng...

Lower Bounds for Local Monotonicity Reconstruction from Transitive-Closure Spanners

Given a directed graph G = (V,E) and an integer k ≥ 1, a ktransitive-closure-spanner (k-TC-spanner) of G is a directed graph H = (V,EH) that has (1) the same transitive-closure as G and (2) diameter at most k. Transitive-closure spanners are a common abstraction for applications in access control, property testing and data structures. We show a connection between 2-TC-spanners and local monoton...

Discrete optimization using quantum annealing on sparse Ising models

*Correspondence: William G. Macready, D-Wave Systems, 3033 Beta Ave, Burnaby, BC V5G 4M9, Canada e-mail: [email protected] This paper discusses techniques for solving discrete optimization problems using quantum annealing. Practical issues likely to affect the computation include precision limitations, finite temperature, bounded energy range, sparse connectivity, and small numbers of qubits. To...