角规原理引进我国已有二十多年的历史。在长期的生产实践中,角规测树是颇受欢迎的有效方法。但也出现一些问题。不少同志为此进行了大量试验、改进工作。断面积系数的研究林业部调查规划院汪兆忠、云南林勘四大队黄杏模等同志,曾就角规断面积系数问题,在室内外均作了试验研究。他们在一张按一定比例的坐标纸上,用随机撒米粒的方法,构成 Angle gauge principle introduced our country has more than 20 years of history. In the long-term production practice, angle measurement tree is a popular and effective method. But there are some problems. Many comrades conducted a large number of tests to this end to improve their work. Research on Cross-sectional Area Coefficient Wang Zhaozhong, the Planning and Planning Institute of the Ministry of Forestry, and Huang Xingmo, a member of the fourth team of Lin’an Prospect in Yunnan Province, conducted experiments on both indoor and outdoor areas. They are in a certain percentage of the coordinates of the paper, the method of using random grains, constitute