A method to generate a large number of M-ary Perfect Periodic Autocorrelation (PPAC) codes of length N, with good correlation properties, is presented. N+1 perfect sequences are obtained if an inverse discrete Fourier transform (IDFT) is applied to a specific subset of N+1 bipolar sequences derived from maximal-length sequences. This set of perfect sequences has a maximum absolute value of peri...

The equivalence class subset algorithm is a powerful tool for solving a wide variety of constraint satisfaction problems and is based on the use of a decision function which has a very high but not perfect accuracy. Perfect accuracy is not required in the decision function as even a suboptimal solution contains valuable information that can be used to help find an optimal solution. In the harde...

Let k be a perfect field, and X an irreducible smooth projective curve over k. We give criterion for vector bundle to admit logarithmic connection singular finite subset of with given residues, where residues are assumed rigid.

For any C ⊆ R there is a subset A ⊆ C such that A + A has inner measure zero and outer measure the same as C + C. Also, there is a subset A of the Cantor middle third set such that A+A is Bernstein in [0, 2]. On the other hand there is a perfect set C such that C + C is an interval I and there is no subset A ⊆ C with A + A Bernstein in I.

In 1] Levenshtein and Vinck investigated perfect run{length{limited codes which are capable of correcting single peak shifts. As a basic combinatorial tool for the construction of such codes they introduced the concept of a t{shift N{design, which is deened to be an N{elementary subset H = fh 1 ; : : : h N g of a nite additive Abelian group G, with the property that for any = 1; : : : t and any...

The perfect phylogeny model for haplotype evolution has been successfully applied to haplotype resolution from genotype data. In this study we explore the application of the perfect phylogeny model to other problems in the design and analysis of genetic studies. We consider a novel type of data, xor-genotypes, which distinguish heterozygote from homozygote sites but do not identify the homozygo...

In the paper, we propose three threshold secret sharing schemes that are based on difference equations. The first scheme is a (t, n)− threshold scheme which is an ideal perfect secure. The other two schemes add the restricted order structure to the set of shadows and the access structure of secret sharing policy. The basis of the access structure of one scheme allows that only subsets that cont...