Fracture Toughness Evaluation in the Transition Region of Reactor Pressure Vessel Steel by Kunio ONIZAWA and Masahide SUZUKI Tokai Research Establishment Japan Atomic Energy Research Institute Tokai-mura, Naka-gun, Ibaraki-ken, 319-11, Japan to be presented at the IAEA Specialists Meeting on Irradiation Etribrittlemeiit and Mitigation Finland, Espoo VTT, Main Building 23-26 October, 1995