Abstract: A power amplifier provides relatively stable quiescent current while maintaining relatively high signal gains and peak to quiescent current ratios. The power amplifier has an input stage and a current mirror stage and incorporates a control transistor between these stages. The control transistor transitions to the triode mode for small inputs and offset voltages thereby reducing the amplifier circuit's gain. However, the control transistor transitions from the triode region to saturation as the input signal becomes larger thereby allowing the amplifier circuit to maintain a relatively high gain for large inputs. Accordingly, better quiescent current characteristics can be obtained without significantly sacrificing performance.

Abstract: A method for initiating cavitation within the fluid within a cavitation chamber is provided. In the cavitation preparatory steps, a hydraulically actuated piston is fully retracted and then the cavitation chamber is isolated. The hydraulic piston is then fully extended after which the chamber is partially opened until a predetermined cavitation piston position is obtained. After the chamber is once again isolated, cavities are formed and imploded by retracting and then extending the cavitation piston. At least one impeller, located within the cavitation chamber, is rotated in order to stabilize the cavities.

Abstract: An acoustic driver assembly for use with any of a variety of cavitation chamber configurations, including spherical and cylindrical chambers as well as chambers that include at least one flat coupling surface, is provided. The acoustic driver assembly includes at least one transducer, a head mass and a tail mass. The end surface of the head mass is shaped so that only a ring of contact is made between the outer perimeter of the head mass of the driver assembly and the cavitation chamber to which the driver is attached. The area of the contact ring is controlled by shaping its surface.

Abstract: An acoustic driver assembly for use with any of a variety of cavitation chamber configurations, including spherical and cylindrical chambers as well as chambers that include at least one flat coupling surface. The acoustic driver assembly includes at least one transducer, a head mass and a tail mass. The end surface of the head mass is shaped to limit the contact area between the head mass of the driver assembly and the cavitation chamber to which the driver is attached, the contact area being limited to a centrally located contact region. The area of contact is controlled by limiting its size and/or shaping its surface.

Abstract: A method for initiating cavitation within the fluid within a cavitation chamber is provided. In the cavitation preparatory steps, a hydraulically actuated piston is fully retracted and then the cavitation chamber is isolated. The hydraulic piston is then fully extended after which the chamber is partially opened until a predetermined pressure is obtained. After the chamber is once again isolated, cavities are formed and imploded by retracting and then extending the cavitation piston. At least one impeller, located within the cavitation chamber, is rotated in order to stabilize the cavities.

Abstract: A method for forming and imploding cavities within a cavitation chamber is provided. The method uses a cavitation piston, coupled to a hydraulically actuated piston, to form the desired cavities during piston retraction and then implode the cavities during piston extension. The cavitation fluid is degassed prior to hydraulically driving cavitation within the chamber. Degassing can be performed within the cavitation chamber or within a separate degassing chamber. In one aspect, a coupling sleeve is interposed between the hydraulic driver and the cavitation chamber. Preferably the coupling sleeve is evacuated. In another aspect, a cavitation fluid circulatory system is coupled to the cavitation chamber. In-line valves on the chamber inlets allow the chamber to be isolated, when desired, from the circulatory system.

Abstract: A method of degassing cavitation fluid using a closed-loop cavitation fluid circulatory system is provided. The procedure is comprised of multiple stages. During the first stage, the cavitation fluid contained within the reservoir is degassed using an attached vacuum system. During the second stage, the cavitation fluid is pumped into the cavitation chamber and cavitated. As a result of the cavitation process, gases dissolved within the cavitation fluid are released. The circulatory system provides a means of pumping the gases from the chamber and the vacuum system provides a means of periodically eliminating the gases from the system. A third stage, although not required, can be used to further eliminate gases dissolved within the cavitation fluid. During the third stage cavities are formed within the cavitation fluid within the chamber using any of a variety of means such as neutron bombardment, laser vaporization or localized heating.

Abstract: A method for initiating cavitation within the fluid within a cavitation chamber is provided. In the cavitation preparatory steps, a hydraulically actuated piston is fully retracted and then the cavitation chamber is isolated. The hydraulic piston is then fully extended after which the chamber is partially opened until a predetermined cavitation piston position is obtained. After the chamber is once again isolated, cavities are formed and imploded by retracting and then extending the cavitation piston. At least one impeller, located within the cavitation chamber, is rotated in order to stabilize the cavities.

Abstract: A method for forming and imploding stabilized cavities within a cavitation chamber is provided. A hydraulically actuated piston is withdrawn to form the desired cavities and then extended to implode the cavities. At least one impeller is rotated in order to stabilize the cavities, the impeller being located within the cavitation chamber and magnetically coupled to an external drive system.

Abstract: A method of degassing cavitation fluid using a closed-loop cavitation fluid circulatory system is provided. The procedure is comprised of multiple stages. During the first stage, the cavitation fluid is continuously circulated through the cavitation chamber, reservoir and the circulatory system while the fluid within the chamber is cavitated. A vacuum system coupled to the fluid reservoir periodically degasses the fluid. During the second stage, pumping of the cavitation fluid through the chamber is discontinued. Gases released by the cavitation process are periodically pumped out of the chamber and periodically eliminated by the vacuum system. A third stage, although not required, can be used to further eliminate gases dissolved within the cavitation fluid. During the third stage cavities are formed within the cavitation fluid within the chamber using any of a variety of means such as neutron bombardment, laser vaporization or localized heating.

Abstract: A flood control system including panels made from plastic sheeting adhered to a frame and stacked one on top of the other. The panels are held in position by a series of columns, each of the columns having an H-shaped cross section that provides for and defines panel receiving slot adapted and arranged to interact with gaskets on the panels to provide a water tight barrier.