President Memorandum

Application of thyristor motors for Blower and Exhaust Fans In 1958, 17 years before the Enasan Tunnel was opened, the Kanmon Tunnel(3461m), Japan’s

　People from various technical fields, such as civil engineering, architecture, and equipment (Mechanical, Electrical, System Control) are involved in long tunnel construction. The

I have been involved in Ventilation control of road tunnels for about 50 year and started Sohatsu Systems Laboratory for more than 20