通过对实型铸造干砂振动填充紧实中的振动方向、维数、频率、加速度及干砂种类等诸多影响要素的测定实验，研究了实型铸造振动紧实干砂的性能。

Vibratory compactability of dry sand in full mold foundry has been researched by experiments on effective factors such as vibratory direction, dimensions, frequency, acceleration and dry sand sorts.

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其中基础类包是应用类包和组合类包的基础，它用点、线、面、体、复杂对象和关系类等基本的要素表示三维空间。

The base package including point class, line class, area class, volume class, complex object class and relation class, is the base of the application package and the combination package.

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其中基础类包是应用类包和组合类包的基础，它用点、线、面、体、复杂对象和关系类等基本的要素表示三维空间。

The base package including point class, line class, area class, volume class, complex object class and relation class, is the base of the application package and the combination package.

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