算术控制

numerical control───[自]数字控制；数值控制

biological control───生物防治；[生物物理]生物控制

numerical controls───[自]数字控制；数值控制

automatic gain control───[电子]自动增益控制

automatic gain controls───[电子]自动增益控制

air traffic control───空中交通管制；空中交通管制队

air-traffic control───空中交通管制；空中交通管制队

Ways to increase precision, such as arithmetical mean and implant control point, were studied and their principles and characters were analyzed and discussed.───研究了算术平均值法、加入控制点法等多种提高精度的方法，分析和讨论了其原理和特点。