Until Second World War period, some scholars only started to these economic phenomena to conduct the research, contained the underground economy research.

直到第二次世界大战期间，一些学者才开始对这些经济现象进行研究，其中也包含了对地下经济的研究。

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It offered an useful reference for the relative project supervision in order to conduct the new "Technical Regulations of City Underground Pipeline Location" in better way.

为同行更好地执行新《城市地下管线探测技术规程》中有关工程监理的要求，提供了有益的参考。

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Future models of the mechanical mollusk could be used for invasive surgeries or to conduct tests in hard to reach places like oil wells thousands of feet underground, said Hosoi.

CNN: Snails inspire design for state-of-the-art robots