1. an arithmetic operation in which the difference between two numbers is calculated;

   "the subtraction of three from four leaves one"
   "four minus three equals one"
   

2. the act of subtracting (removing a part from the whole);

   "he complained about the subtraction of money from their paychecks"
   

1. 差集：我们可以用AME的并集(Unions) 、差集(subtraction)和交集(Intersections)等功能组建组合体. 图1中,由左至右分别是两个圆柱体叠加、切割、和求交集后的立体图. 如图五即为AutoCAD所绘图样,当在(Floating Model Space)模式下绘出图四的三视图后,

2. 减少：Differential In-Gel Analysis (DIA) 模块实现背景减少(subtraction), 归一化,量化,和在一个相同胶内的来自两个和三个样本的斑点匹配. 当使用多重胶的时候,由汇聚成(pooled)的内部标准的链接,采用BVA (Biological Variation Analysis )模块,

3. subtraction

3. 减：下面是使用上面所述的机制的3个基本的CSG操作:合并(Union)、相交(Intersection)和减(subtraction). CSG是从简单的实体的逻辑组合来构建复杂的实体的过程. 基本的逻辑操作(如合并、相交和补集)用来作为三维实体之间的关系操作. 在这些算法中,

4.subtraction：sub; 配合减影