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Thermal conductivity measuring methods can be divided into steady-state method and non-steady-state method by macroscopic mechanism of thermal conductivity. 

Steady-state method requires long period ,and there are also many other factors which affect measuring accuracy. However, non-steady-state method has the advantage of short measuring time, high accuracy and low requirements for operational environment. Especially, the transient hot-wire method has been considered internationally as the best measuring method of thermal conductivity in the research area of thermal conductivity.