2. To create a
rectangle or oval with 3D effects, select the desired shape from the basic shapes menu.
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要创建一个具有3D效果的矩形或椭圆形,从基本形状菜单选择所需的形状。
3. This subject introduce some common
rectangle ore pillars and its advantages, and rock mechanics analysis and evaluation of
rectangle ore pillars support effects.
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介绍了几种常见矩形矿柱及其优点,并对矩形矿柱的支撑效果进行岩石力学分析和评价。