, shows that the Nadanhada Terrane and the Mino Terrane, which were originally a single superterrane in Paleogene before the opening of the Japan Sea and formed near the Equator in Triassic Period constituted a belt of accretionary complexes from Jurassic to Cretaceous along the eastern continental margin of Asia.

Relation between the circle air and gas concentration;

Forecast of coalmine gas concentration based on the immune neural network model;

The paper introduced composition,working principle,design of hardware and software of a monitoring system of gas concentration based on AT89C2051 single-chip microcomputer and VB6.

Based on contrast of methane concentration from calculation with one from experiment, a simulation on methane concentration in tunnel is completed.

Through determining methane concentration distribution in goaf of 3211 coal face in Yicheng coal mine, methane concentration distribution law in goaf of room and pillar mining coal face is found out preliminarily, thus providing scientific basis for methane drainage and methane accidents prevention and control in goaf.

This paper achieved the methane control system can realize undergroun mining well by microcomputer,methane concentration real time control and have easy structure,low cost,high relia bility and strong control ability.