As the frontier of the whole science and technology system, metrology science is an important technological foundation of national economic and social development, and is one of the three pillars of modern industrial development. Metrology can realize the unification of units and guarantee accurate and reliable values, which is related to the national economy and peoples livelihood. It involves all fields in all industries and plays a role of guidance, supervision and guarantee in measurement according to the law. The level of measurement testin...