Abstract: A large-capacity WLL base station 7 as a wireless local loop base station is wirelessly linked to a PHS radio station 10 of about 10 channels which accepts the connection thereto of various PHS terminals 12 and a fixed subscriber's terminal 11 which can accommodate a plurality of fixed telephone sets 13, by use of a PHS band different from that of the PHS terminal 12. The fixed subscriber's terminal 11 and the PHS radio station 10 are located within one communication area of the large-capacity WLL base station 7. Thereby, it is provided a radio communication system which provides efficient construction of wireless communications facilities by locating subscribers of a wireless local loop and a base station for microcell-basis, portable communication terminals within a communication area.

Abstract: An internally meshing planetary gear structure or a flexible meshing type gear meshing structure is intended to achieve the lightening, miniaturization and high load capacity by increasing the meshing points of the gear even is the difference in the teeth number between the external gear and the internal gear is two or more. The difference in the teeth number between each of the external gears and the internal gear is set to be N (N: integer being two or more), the tooth profile of the external gear is constructed on the basis of the innermost curve of the epitrochoid parallel curves in N pieces which are superposed to be shifted in phase from each other, and the tooth profile of the internal gear is constructed on the basis of the innermost curve of the trochoid internally enveloping curves in N pieces which mesh with the above epitrochoid parallel curves and which are superposed to be shifted from each other by the same phase as in the external gear.

Abstract: An internally meshing planetary gear structure or a flexible meshing type gear meshing structure is intended to achieve the lightening, miniaturization and high load capacity by increasing the meshing points of the gear even is the difference in the teeth number between the external gear and the internal gear is two or more. The difference in the teeth number between each of the external gears and the internal gear is set to be N (N: integer being two or more), the tooth profile of the external gear is constructed on the basis of the innermost curve of the epitrochoid parallel curves in N pieces which are superposed to be shifted in phase from each other, and the tooth profile of the internal gear is constructed on the basis of the innermost curve of the trochoid internally enveloping curves in N pieces which mesh with the above epitrochoid parallel curves and which are superposed to be shifted from each other by the same phase as in the external gear.

Abstract: A polymer obtained by the polymerization of a substituted 1,3-butadiene compound of the formula: ##STR1## wherein each of X.sub.1 and X.sub.2 is hydrogen or SiR.sub.1 R.sub.2 R.sub.3, provided that at least one of X.sub.1 and X.sub.2 is SiR.sub.1 R.sub.2 R.sub.3, wherein each of R.sub.1, R.sub.2 and R.sub.3 is halogen, lower alkyl or lower alkoxy, provided that R.sub.1, R.sub.2 and R.sub.3 are not lower alkyl at the same time.