A discrete-time variable structure controller for aircraft elevator control using the method for control of plants with finite zeros in canonical subspace is proposed in this paper. First, a discrete mathematical model of the system over canonical space, using the delta transform, is given. Then, decomposition of the canonical space to subspaces with and without control is carried out by introd...

Let Φ ∈ Rm×n be a sparse Johnson-Lindenstrauss transform [KN] with s non-zeroes per column. For T a subset of the unit sphere, ε ∈ (0, 1/2) given, we study settings for m, s required to ensure E Φ sup x∈T ∣∣‖Φx‖22 − 1∣∣ < ε, i.e. so that Φ preserves the norm of every x ∈ T simultaneously and multiplicatively up to 1 + ε. In particular, our most general theorem shows that it suffices to set m = ...

We present a new efficient localized algorithm to construct, for any given quasi-unit disk graph G = (V ,E) and any ε > 0, a (1+ ε)-spanner for G of maximum degree O(1) and total weight O(ω(MST )), where ω(MST ) denotes the weight of a minimum spanning tree forV . We further show that similar localized techniques can be used to construct, for a given unit disk graphG = (V ,E), a planarCdel(1+ε)...

Polymer-nanoparticle (NP) interfacial interactions are expected to strongly influence the properties of nanocomposites, but surprisingly, experiments often report small or no changes in the glass transition temperature, Tg. To understand this paradoxical situation, we simulate nanocomposites over a broad range of polymer-NP interaction strengths, ε. When ε is stronger than the polymer-polymer i...

A visualization of three-dimensional incompressible flows by divergence-free quasi-twodimensional projections of the velocity field onto three coordinate planes is revisited. An alternative and more general way to compute the projections is proposed. The approach is based on the Chorin projection combined with a SIMPLE-like iteration. Compared to the previous methodology based on divergence-fre...

The boundary integral method is an efficient approach for solving time-harmonic acoustic obstacle scattering problems. The main computational task is the evaluation of an oscillatory boundary integral at each discretization point of the boundary. This paper presents a new fast algorithm for this task in two dimensions. This algorithm is built on top of directional low-rank approximations of the...

The optical behaviour of the (human) cornea is often characterized with the Zernike-coefficients derived via the Zernike-transform of its optical power map. In this paper, a radial transform based on the Chebyshev-polynomials of the second kind is suggested for a surface-based, rather than an optical power map based representation of the cornea. This transform is well-suited for providing compa...

Over the past few years, attempts to scale up infinite-horizon DECPOMDPs with discounted rewards are mainly due to approximate algorithms, but without the theoretical guarantees of their exact counterparts. In contrast, ε-optimal methods have only theoretical significance but are not efficient in practice. In this paper, we introduce an algorithmic framework (β-PI) that exploits the scalability...

IDR(s) is one of the most efficient methods for solving large sparse nonsymmetric linear systems of equations. We present two useful extensions of IDR(s), namely a flexible variant and a multi-shift variant. The algorithms exploit the underlying Hessenberg decomposition computed by IDR(s) to generate basis vectors for the Krylov subspace. The approximate solution vectors are computed using a Qu...

The dynamics and stability of multi-spot patterns to the Gray-Scott (GS) reaction-diffusion model in a two-dimensional domain is studied in the singularly perturbed limit of small diffusivity ε of one of the two solution components. A hybrid asymptotic-numerical approach based on combining the method of matched asymptotic expansions with the detailed numerical study of certain eigenvalue proble...