A staff of an exam place installs mobilephone signal shield instrument in Hefei, capital of east China's Anhui Province, June 6, 2006. New apparatus will be applied to prevent cheating in the national college entrance exam scheduled on June 7-8. (Xinhua Photo)

A staff checks a mobilephone signal shield instrument in a exam room of Jinan, capital of east China's Shandong Province, June 6, 2006. (Xinhua Photo)

Two invigilators check a detector in an exam room in Suzhou, east China's Jiangsu Province, June 6, 2006. (Xinhua Photo)

Two staff workers adjust monitors in Shenyang No. 5 High School, one of the examination places, in Shenyang, capital of northeast China's Liaoning Province, on June 6, 2006. (Xinhua Photo)