Phonograph record Gramophone trademark, Berliner started marketing records of 7 inches diameter with somewhat more substantial entertainment value, along with somewhat more substantial gramophones to play them. Berliner's records had poor sound quality compared to wax cylinders, but his manufacturing associate Eldridge R. Johnson eventually improved it. Abandoning Berliner's "Gramophone" trademark for legal reasons, in 1901 Johnson's and Berliner's separate companies reorganized to form the Victor Talking Machine Company in Camden, New Jersey, whose products would come to dominate the market for many years. Emile Berliner moved his company to Montreal in 1900. The factory, which became the Canadian branch of RCA
Hydraulic diameter also used in calculation of heat transfer in internal-flow problems. For a fully filled duct or pipe whose cross-section is a regular polygon, the hydraulic diameter is equivalent to the diameter of a circle inscribed within the wetted perimeter. Hydraulic diameter The hydraulic diameter, , is a commonly used term when handling flow in non-circular tubes and channels. Using this term, one can calculate many things in the same way as for a round tube. It is defined as where More intuitively, the hydraulic diameter can be understood as a function of the hydraulic radius , which is defined as