A novel approach to heteropolymer design is proposed. It is based on the
criterion by Kurosky and Deutsch, with which the probability of a target
conformation in a conformation space is maximized at low but finite
temperature. The key feature of the proposed approach is the use of soft spins
(fuzzy monomers) that leads to a design equation, which is an analog of the
Boltzmann machine learning equation in the design problem. We implement an
algorithm based on the design equation for the generalized HP model on the
3x3x3 cubic lattice and check its performance.Comment: 7 pages, 3 tables, 1 figures, uses jpsj.sty, jpsjbs1.sty, epsf.sty,
Submitted to J. Phys. Soc. Jp