Impulsive noise is often encountered in the practical active noise control (ANC) applications. Traditional ANC algorithms fail to control such noise. Derived by minimizing the l1 norm of an estimated a posteriori error vector, a new filtered-x affine projection sign algorithm (NFxAPSA) is proposed to efficiently and effectively suppress impulsive noise. Two typical extensions, such as variable ...

In this paper, we will derive some twist criteria for the periodic solution of a periodic scalar Newtonian equation using the third order approximation. As an application to the forced pendulum ẍ + ω2 sinx = p(t), we will find an explicit bound P (ω) for the L1 norm, ‖p‖1, of the periodic forcing p(t) using the frequency ω as a parameter such that the least amplitude periodic solution of the fo...

In this paper, we consider the stability of an inverse spectral problem for a nonsymmetric ordinary differential operator. We give an estimate for deviation in the coefficients of this operator when the spectral data perturb. Our result shows that if two spectral data are sufficiently close to one another, then the corresponding two differential operators must be close each other in the sense o...

This paper deals with the k-sample problem for functional data when the observations are density functions. We introduce test procedures based on distances betweenpairs of density functions (L1 distance andHellinger distance, amongothers).A simulation study is carried out to compare the practical behaviour of the proposed tests. Theoretical derivations have been done in order to allow weighted ...

Given an embedding f: G -+ 2 of a graph G in the two-dimensional lattice, let Iff be the maximum L1 distance between points f(x) and f(y) where xy is an edge of G. Let B2 ( G) be the minimum Ifl over all embeddings f. It is shown that the determination of B2 ( G ) for arbitrary G is NP-complete. Essentially the same proof can be used in showing the NP-completeness of minimizing If I over all em...

We are interested in the convergence of the value of n-stage games as n goes to infinity and the existence of the uniform value in stochastic games with a general set of states and finite sets of actions where the transition is commutative. This means that playing an action profile a1 followed by an action profile a2, leads to the same distribution on states as playing first the action profile ...

Hardy was surprised by Ramanujan’s remark about a London taxi numbered 1729: “it is a very interesting number, it is the smallest number expressible as a sum of two cubes in two different ways”. In memory of this story, this number is now called Taxicab(2) = 1729 = 9 + 10 = 1 + 12, Taxicab(n) being the smallest number expressible in n ways as a sum of two cubes. We can generalize the problem by...

We consider a model equation for 3D vorticity dynamics of incompressible viscous fluid proposed by K. Ohkitani and the second author of the present paper. We prove that a solution blows up in finite time if the L1-norm of the initial vorticity is greater than the viscosity.

An n-town, n ∈ N, is a group of n buildings, each occupying a distinct position on a 2-dimensional integer grid. If we measure the distance between two buildings along the axis-parallel street grid, then an n-town has optimal shape if the sum of all pairwise Manhattan distances is minimized. This problem has been studied for cities, i.e., the limiting case of very large n. For cities, it is kno...