A feasibility experiment on an automatic signature verification system based on writing pressure was conducted using a new device sensing the z-axis component of writing pressure. The data acquisitions were conducted over a half a year for checking both subjects' and device stabilities. The DP (dynamic programming) matching method provided 6% error rates for type I and type II errors. The nature of signature writing pressure was investigated.

The Assmus-Mattson theorem is a method to find designs in linear codes over a finite field. The purpose of this paper is to give an analog of this theorem for Z/sub 4/-codes by using the harmonic weight enumerator introduced by Bachoc. This theorem can find some 5-designs in the lifted Golay code over Z/sub 4/ which were discovered previously by other methods.