one of the most important problems in geodesy is the unification of height datum. generally in geodesy; there are two types of height systems, the geometrical height based on ellipsoid and the physical height based on gravity-defined surface (zhang et al, 2009).local height datum is determined according to mean sea level (msl). in regarding to mismatch of mean sea level and geoid, on the one ha...

We extend simulations of simplicial gravity in four dimensions to include degenerate triangulations and demonstrate that using this ensemble the geometric finite-size effects are much reduced. We provide strong numerical evidence for the existence of an exponential bound on the entropy of the model and establish that the phase structure is identical to that of a corresponding model restricted t...

A “coaxial” transmission line has inner conductor of radius a and outer conductor of radius b, but the axes of these two cylinders are offset by a small distance δ ¿ b. Deduce the capacitance and inductance per unit length, and the impedance Z, accurate to order δ/b. The (relative) dielectric constant and permeability of the medium between the two conductors both unity. The relevant frequencies...