Reuters Nagoya, Japan- The World RoboCup opened in this Japanese city and soccer may never be the same again. Instead of Ronaldo, Shearer and Zola displaying their skills, there were robots, some as tall as 1.2 metres (four feet), scurrying around mini-soccer fields trying to put the ball in the net. The event, officially known as the "First Robot World Cup Initiative", was the highlight of the 15th International Joint Conference on Artificial Intelligence, an annual meeting where scientists