Seismic Response of a Linear, 2-D Model of the Marina District

The recorded response of the Marina District of the City of San Francisco to an aftershock of the 1989 Loma Prieta earthquake is simulated using a two-dimensional model of the sedimentary deposits. Even though the response of the Marina is truly three-dimensional, the two-dimensional model successfully captures some important aspects of the response and consequently may be useful for predicting strong ground motion in the Marina District for engineering applications

Eigenvector Approximation Leading to Exponential Speedup of Quantum Eigenvalue Calculation

We present an efficient method for preparing the initial state required by the eigenvalue approximation quantum algorithm of Abrams and Lloyd. Our method can be applied when solving continuous Hermitian eigenproblems, e.g., the Schroedinger equation, on a discrete grid. We start with a classically obtained eigenvector for a problem discretized on a coarse grid, and we efficiently construct, quantum mechanically, an approximation of the same eigenvector on a fine grid. We use this approximation as the initial state for the eigenvalue estimation algorithm, and show the relationship between its success probability and the size of the coarse grid.Comment: 4 page

On a Dirichlet problem with (p,q)(p,q)-Laplacian and parametric concave-convex nonlinearity

A homogeneous Dirichlet problem with $(p,q)$-Laplace differential operator and reaction given by a parametric $p$-convex term plus a $q$-concave one is investigated. A bifurcation-type result, describing changes in the set of positive solutions as the parameter $\lambda>0$ varies, is proven. Since for every admissible $\lambda$ the problem has a smallest positive solution $\bar u_{\lambda}$, both monotonicity and continuity of the map $\lambda \mapsto \bar u_{\lambda}$ are studied.Comment: 12 pages, comments are welcom

Noise induced state transitions, intermittency and universality in the noisy Kuramoto-Sivashinsky equation

We analyze the effect of pure additive noise on the long-time dynamics of the noisy Kuramoto-Sivashinsky (KS) equation in a regime close to the instability onset. We show that when the noise is highly degenerate, in the sense that it acts only on the first stable mode, the solution of the KS equation undergoes several transitions between different states, including a critical on-off intermittent state that is eventually stabilized as the noise strength is increased. Such noise-induced transitions can be completely characterized through critical exponents, obtaining that both the KS and the noisy Burgers equation belong to the same universality class. The results of our numerical investigations are explained rigorously using multiscale techniques.Comment: 4 pages, 4 figure

Monolithic Implementation of a Planar Gunn Diode and a pHEMT

No abstract available