Let Uβ be the special Buekenhout-Metz unital in PG(2, q 2) formed by a union of q conics, where q = pe is an odd prime power. It can be shown that the dimension of the binary code of the corresponding unital design Uβ is less than or equal to q3 + 1− q. Baker and Wantz conjectured that equality holds. We prove that the aforementioned dimension is greater than or equal to q3(1− 1 p ) + q 2 p .

The problem of providing bounds on the redundancy of an optimal code for a discrete memoryless source in terms of the probability distribution of the source, has been extensively studied in the literature. The attention has mainly focused on binary codes for the case when the most or the least likely source letter probabilities are known. In this paper we analyze the relationships among tight l...

We consider upper bounds on two fundamental parameters of a code; minimum distance and covering radius. New upper bounds on the covering radius of non-binary linear codes are derived by generalizing a method due to S. Litsyn and A. Tiett avv ainen 10] and combining it with a new upper bound on the asymptotic information rate of non-binary codes. The new upper bound on the information rate is an...

A code is presented for fast, easy and efficient communication over channels that allow only two signal types: a single sound (e.g. a knock), or no sound (i.e. silence). This is a true binary code while Morse code is a ternary code and does not work in such situations. Thus the presented code is more universal than Morse and can be used in much more situations. Additionally it is very tolerant ...

This paper presents an overview of dynamic binary translation. Dynamic binary translation is the process of translating code for one instruction set architecture to code for another on the fly, i.e., dynamically. Dynamic binary translators are used for emulation, migration, and recently for the economic implementation of complex instruction set architectures. Most of the problems occuring in dy...

A new series of Z4-linear codes of high minimum Lee distance is given. It is derived from the Z4-linear representation of the Kerdock codes. The Gray image of the smallest of these codes is a nonlinear binary (114, 2, 56)-code, and in the second smallest case the Gray image is a nonlinear binary (1988, 2, 992)-code. Both codes have at least twice as many codewords as any linear binary code of e...

A number of upper and lower bounds are obtained for K( n, R), the minimal number of codewords in any binary code of length n and covering radius R. Several new constructions are used to derive the upper bounds, including an amalgamated direct sum construction for nonlinear codes. This construction works best when applied to normal codes, and we give some new and stronger conditions which imply ...