SHARP EYES: With China’s economic incentives becoming less effective at influencing Taiwanese, Beijing has had to rely increasingly on other measures, the NSB’s head said By Huang Ching-hsuan and William Hetherington / Staff reporter, with staff writer Beijing carries out comprehensive and systematic surveillance of visitors and residents within its borders, and Taiwanese traveling to China should pay close attention to their personal safety following China’s implementation of the Ethnic Unity and Progress Promotion Law, National Security Bureau (NSB) Director-General Tsai Ming-yen (蔡明彥) said yesterday.Speaking at a meeting of the legislature’s Foreign Affairs and National Defense Committee, Tsai said the law, which took effect on Wednesday last week, gives Chinese authorities broad discre