Journal of Northeastern University(Natural Science)
Method for Determining Design Time Based on Difficulty Coefficient of Product Design
GU Meng-yao， CHEN You-ling， DU Xuan-xuan
Journal of Northeastern University Natural Science . 2017, (1): 111 -115 .  DOI: 10.12068/j.issn.1005-3026.2017.01.023