With the countdown to E-Day - April 28 - being slickly monitored by space-age business techniques, the Canadian Corporation for the 1967 World Exhibition's headquarters staff have all systems go. Directing the efforts of a 10,000-strong army of workers busy on the final stages of preparing 1,000 acres of man-made wonders, the corporation's control centres are also running a network of other operations. Using the modern technology of computers, electronic automatic telephones and the latest in other communication devices, they are keeping a constant watch on such things as the available accommodation within 100 miles of the world's fair, the training of more than 200 multi-lingual, charming hostesses, the maintenance of a vast information service and the polishing and testing of elaborate control techniques to smooth the paths of 35 million visitors expected between April 28 and October 27 - when Expo 67 will present an exciting pageant of man's achievements by the nations of the world.