Vertical static pendulums have been installed in mines or caves in Central Europe since 2007. Two-dimensional optical measurement of the tilt of a rock mass and continuous fully digital on-line evaluation of results makes possible the detection of a small tilt of the surroundings with a resolution of tens of nanoradians or the deformation of the surroundings in the horizontal plane wi... https://www.hindigyanvishv.com/top-super-Centehua-Distressed-Southwestern-Aztec-Area-Rug-special-buy/