Abstract: A method for determining motional branch current in an ultrasonic transducer of an ultrasonic surgical device over multiple frequencies of a transducer drive signal. The method may comprise, at each of a plurality of frequencies of the transducer drive signal, oversampling a current and voltage of the transducer drive signal, receiving, by a processor, the current and voltage samples, and determining, by the processor, the motional branch current based on the current and voltage samples, a static capacitance of the ultrasonic transducer and the frequency of the transducer drive signal.

Abstract: A check valve for a fluid handling system is disclosed, the check valve having a main body with a poppet valve disposed therein and a spring urging the poppet valve into abutment with an inner surface of the main body, wherein the check valve facilitates a flow of fluid in one direction and militates against the flow of fluid in an opposite direction.

Abstract: A keyless entry system is disclosed for use in an entry system wherein the latching mechanism may be locked or unlocked by either a key or a remotely controlled mechanism.

Abstract: A porous high-silica core is disclosed for use in directional solidification casting processes having exceptional thermal stability at temperatures above 1650.degree. C. and containing mineralizers which promote the formation of cristobalite. The cores may be made by mixing at least 75 parts of essentially pure fused silica particles with 1 to 25 parts of activating particles containing a mineralizer, such as an alkali metal or alkaline earth metal compound, may be fired at a temperature of 1000.degree. to 1300.degree. C. until they contain 35 percent or more of cristobalite and may then be cooled to room temperature. They may thereafter be incorporated in a shell mold in accordance with the "lost-wax" process and preheated with the shell mold at a temperature of 1300.degree. to 1600.degree. C. to provide a cristobalite content of 60 to 85 percent or more within a short period of time, such as 10 to 30 minutes, and before a molten superalloy is allowed to flow into the mold.