Antagonistic pairs of muscles are muscle where one move the bone in one direction and the other moves it back the other way in transmission of nerve impulses to the muscles.
Demag, which manufactures and distributes telescopic and lattice boom cranes, is one of the leading mobile crane producers worldwide, with 2001 revenues of approximately $360 million.
For the girder place, overhead crane can be divided into two types, top running overhead crane and underhung bridge crane. Top travelling crane has many functions, different loading capacity, can be used for light work and heavy duty work. Underhung type is one kind of small crane. It has compact structure, low headroom, and light weight, very suitable for the places with restricted height.