MILWAUKEE (AP) – A Milwaukee group of fans of Japanese cartoon style animation are meeting in downtown Milwaukee this week.   According to tourism officials, this year’s convention will feature anime voice actors, fan and guest panels, a costume contest, a 24-hour video game and table-top game rooms, among other things.        The convention drew about 3,500 attendees last year and organizers are expecting the same this year.  The Japanese Animation Association founded the group at the University of Wisconsin-Milwaukee and it’s now run by the Entertainment and Cultural Promotions Society.   Anime is a multibillion dollar industry ranging from TV, DVDs and video games to toys and trinkets. It explores a surreal world of fantasy and science fiction.  The seventh-annual convention runs Friday through Sunday.