Abstract: A high-speed add-compare selection apparatus, for a Viterbi algorithm processing apparatus having a branch metric calculator and a metric memory, is described. First and second previous metric values are supplied from the metric memory to first and second registers. The first previous metric value from the first register and a branch metric value of the present state calculated by the branch metric calculator are added, as are the second previous metric value from the second register and a branch metric value of the next state calculated by the branch metric calculator. The values obtained are compared and a survival metric value calculated accordingly.

Abstract: A method for preparing a high-heat-resistant-epoxy-resin composition which comprises adding, as catalytic curing agent, a quinoxalinium salt having a benzyl group to difunctional and multifunctional epoxy resin and thermoset resin having a similar structure. The epoxy-resin composition obtained by the present invention is excellent in its impregnating property, processability, impact resistance, drug resistance, electric-insulating property, and adhesiveness.

Abstract: A method for preparing a high-heat-resistant-epoxy-resin composition which comprises adding, as catalytic curing agent, a pyrazinium salt having a benzyl group to difunctional and multifunctional epoxy resin and thermoset resin having a similar structure. The epoxy-resin composition obtained by the present invention is excellent in its impregnating property, processability, impact resistance, drug resistance, electric-insulating property, and adhesiveness.

Abstract: A heat-curable resin composition comprising a multifunctional epoxy resin monomer and a heat-latent curing agent of formula (I) provides a cured epoxy resin having good thermal and dimensional stability: ##STR1## wherein: R is hydrogen, a C.sub.1-4 alkyl or C.sub.1-4 alkoxy group.