Through the comparison of technical economy, this paper has analysed the proper layout of individual beds or separate groups for multiple seams of thin and medium thickness in the Ying Cheng Colliery.

本文通过技术经济比较，对营城煤矿条件下，薄及中厚煤层群采区分层或分组的合理布置方式作了分析。用经济分析法确定了在这种条件下采区分组布置的合理界限。

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The new network replaces a single system integrator with multiple teams of contractors who must compete annually for work, creating the kinds of seams and discontinuities intruders might seek to exploit.

FORBES: Cyberwarfare May Be A Bust For Many Defense Contractors