Time-domain eoders use long-term predietors to exploit the quasiperiodie strueture of voiced speech. However, one major drawbaek with classical predictors is the restriction of the delay to integer values, reducing the performance especially when the pitch period is short. This paper presents an extension of the prediction technique to encompass non-integer delays enabling more aeeurate represe...

Isometry classes of linear codes can be expressed as orbits under the group action of a wreath product. Some combinatorial and algebraic methods are discussed which can be applied for generating linear codes distributed uniformly at random over all isometry classes.

In this note, we consider a generalized Fibonacci sequence fung : Then give a generating matrix for the terms of sequence fukng for a positive integer k: With the aid of this matrix, we derive some new combinatorial identites for the sequence fukng.

The purpose of this paper is to obtain exponential lower bounds on the numbers of non-isomorphic linear codes or symmetric designs of certain types. This will be accomplished using a famil iar--even mundane-ob jec t related to the desarguesian affine plane AG(2, q"). Namely, let V be a 2-dimensional vector space over GF(q") , and let A be its set of l-spaces. We will use subsets £ of A to defin...

We first present an equivalent definition of relative generalized Hamming weights of a linear code and its subcodes, and we develop a method using finite projective geometry. Making use of the equivalent definition and the projective-geometry method, all of the relative generalized Hamming weights of a 3-dimensional q-ary linear code and its subcodes will be determined.

Abstract . Let q he a power of a prime number, Fq the finite field with q elements, n an integer dividing q 1, n > 2, and g a character of order n of the multiplicative group Fq. I f X is an algebraic curve defined over Fq and if G is a divisor on X, we define a non linear code F(q, X, G, n, X) on an alphabet with n + 1 letters.We compute the parameters of this code, through the consideration o...

The present note establishes the equivalence of Mac Williams identities for linear codes C,C⊥ ⊂ Fq with the Polarized Riemann-Roch Conditions for their ζfunctions. It provides some averaging and probabilistic interpretations of the coefficients of Duursma’s reduced polynomial of C.

We calculate the leading order interactions of massless D-brane excitations. Their 4-point functions are found to be identical to those found in type I theory. The amplitude for two massless D-brane fluctuations to produce a massless closed string is found to possess interesting new structure. As a function of its single kinematic invariant, it displays an infinite sequence of alternating zeros...

A minimal subshift (X, T ) is linearly recurrent if there exists a constant K so that for each clopen set U generated by a finite word u the return time to U , with respect to T , is bounded by K|u|. We prove that given a linearly recurrent subshift (X, T ) the set of its non-periodic subshift factors is finite up to isomorphism. We also give a constructive characterization of these subshifts.