Abstract: Two apparatuses are disclosed for providing a dynamically varying water surge in a salt-water reef aquarium. The first apparatus is a micro-controller based variable frequency reef surge drive 100 for an AC permanent magnet synchronous motor (PMSM) submersible aquarium pump. Drive 100 comprises voltage conversion circuitry 105, xmicro-controller 110, reef-surge generation program 115, variable frequency drive 118, mode switch 130 and tidal cycle switch 135. Three user-selectable modes of operation are provided: a random frequency mode, a fixed-program mode and a tidal mode. A second apparatus comprises a novel submersible AC PMSM pump with dual impeller assemblies and dual input and output chambers for supporting forward and reverse flow through an AC PMSM pump.

Abstract: Two apparatuses are disclosed for controlling the speed of an AC synchronous motor-pump utilizing a series of stepped voltage pulses at the driving frequency. The first apparatus is an isolated variable frequency drive comprising step-down transformer 100, full wave rectifier and filter 101, micro-controller 108, driving-voltage array generator 102, gate driver 107, inverter bridge 103 and step-up transformer 104. The second apparatus is a non-isolated high voltage variable frequency drive comprising full wave rectifier and filter 201, low voltage, dual output power supply 205, micro-controller 208, driving-voltage array generator 202, gate driver 207 and inverter bridge 203. Methods are given to determine voltage array values and pulse times to generate a stepped voltage approximation of a sine wave driving waveform.

Abstract: A vertical water wall assembly (100) for generating dynamically changing water patterns in a contained channel (114) behind a viewing surface. The water wall assembly includes a translucent front sheet (110) directed toward a viewing space with a rear side containing a multiplicity of concave depressions (111), and a rear sheet (140) disposed behind and in proximity to the front sheet that in part acts as a contrasting background. The edges of these sheets are sealed (120, 122) and water is made to flow in the space defined between the two sheets, entering at the top of the sheets (135) and exiting at the bottom of the sheets (150). The flow of water into the water wall at the water inlet (125) is time varying and is preferably computer-controlled (190). In operation water flowing in the contained channel (114) of the water wall takes dynamic, chaotic pathways through the multiplicity of concave depressions (111).

Abstract: A vertical water wall assembly (100) for generating dynamically changing water patterns in a contained channel (114) behind a viewing surface. The water wall assembly includes a translucent front sheet (110) directed toward a viewing space with a rear side containing a multiplicity of concave depressions (111), and a rear sheet (140) disposed behind and in proximity to the front sheet that in part acts as a contrasting background. The edges of these sheets are sealed (120, 122) and water is made to flow in the space defined between the two sheets, entering at the top of the sheets (135) and exiting at the bottom of the sheets (150). The flow of water into the water wall at the water inlet (125) is time varying and is preferably computer-controlled (190). In operation water flowing in the contained channel (114) of the water wall takes dynamic, chaotic pathways through the multiplicity of concave depressions (111).

Abstract: An apparatus and a method for preventing buildup of silicon oxides and silicon carbides on the inner surface of exhaust sleeves utilized in Czochralski (Cz) silicon crystal pullers are provided. The apparatus and the method include the provision of a vapor impervious layer coated on the inner surface of an exhaust sleeve, and forming a barrier to silicon oxides and silicon carbides deposition on the inner surface, to prevent the buildup of silicon oxides and silicon carbides on the surface of exhaust sleeves, thereby allowing more uniform laminar flow of process gases in the Cz chamber and the exhaust sleeve, and extending the useful lifetime of exhaust sleeves.

Abstract: An apparatus for calculating fluid flow in a channel, comprising a probe member which detects fluid depth in the channel; a mechanism for measuring average fluid velocity in the channel; a mechanism for correcting the detected fluid depth based upon the measured average fluid velocity in order to account for drawdown; and a mechanism for calculating average flow rate based upon the average fluid velocity measurement and the corrected fluid depth value.

Abstract: A refrigerated automatic fluid sampling apparatus having a compressor assembly mounted in an upper portion thereof, above the thermally-controlled sample compartment. The apparatus includes a thermal control system which prolongs compressor life and optimizes compressor operation by exercising the compressor assembly during prolonged periods of non-use, preventing short-cycling of the compressor, and accurately monitoring sample temperatures to minimize compressor starts. The invention further includes a sampling control system which employs a statistical regression model to simulate real-life pumping system and operating characteristics so as to accurately deliver a predetermined sample volume, which permits sampling on a constant time, variable volume basis as well as other sampling modes.

Abstract: A multi-function fluid flow monitoring apparatus capable of measuring fluid flow-related variables of fluid in a channel on the basis of signals from any one or more of a plurality of different types of flow sensors. Such different types of flow sensors may include, for example, a bubbler-type pressure sensor, a submerged pressure transducer, an ultrasonic transducer, and/or a velocity sensor forming part of an area-velocity sensor system, each of which sensors may be selectively connected to the apparatus as needed to accommodate various monitoring conditions. The apparatus is further capable of monitoring various conditions of fluid in the channel, such as pH level, ORP, temperature, solution conductivity, dissolved oxygen, and the like.