Abstract: Pulse width modulation is used to control the flow rate through a solenoid expansion valve in a refrigeration system using a simple vapor compression cycle. The refrigeration cycle includes a phase separator which receives two phase refrigerant from the condenser and supplies liquid refrigerant to the pulse width modulated solenoid valve. A liquid level sensor is disposed in the phase separator, and a controller for controlling the duty cycle of the pulse width modulated solenoid valve is provided to receive input from the liquid level sensor. The liquid level sensor can be of the type which provides a continuously variable signal as a function of liquid level, or it can be a liquid level switch which controls valve duty cycle on the basis of whether the phase separator liquid level is above or below a set level. Alternatively, two liquid level switches can be provided.

Abstract: Pulse width modulation is used to control the flow rate through a solenoid expansion valve in a refrigeration system using a dual evaporator, two-stage cycle. The refrigeration cycle includes a phase separator which receives two phase refrigerant from the low temperature evaporator and supplies liquid refrigerant to the pulse width modulated solenoid valve. A liquid level sensor is disposed in the phase separator, and a controller for controlling the duty cycle of the pulse width modulated solenoid valve is provided to receive input from the liquid level sensor. The liquid level sensor can be of the type which provides a continuously variable signal as a function of liquid level, or it can be a liquid level switch which controls valve duty cycle on the basis of whether the phase separator liquid level is above or below a set level. Alternatively, two liquid level switches can be provided.

Abstract: According to the present invention, a 3D connectivity-conserved grain-structured processing architecture uses connectable massively parallel processors. A 3D grain-structured processing architecture is provided. The 3D links of the grain-structured processing architecture provide direct local communication as well as global communication for voxel processing and analysis tasks. A novel transport naming scheme which is scalable in any three-dimension direction and the local/global communication protocol are disclosed. The 3D volumetric data set is first divided into a set of voxel sub-cubes. Each voxel subcube is processed by a processor element of the grain-structured processing architecture. Data discontinuity is produced after performing local operations in a massively parallel processors environment and requires replacing the resulted voxel data set in the overlap region for each voxel sub-cube.

Abstract: A superconducting magnet includes a cryocooler coldhead, a sleeve assembly, and a superconducting coil assembly. The sleeve assembly includes a flexible bellows and a sleeve tube and is attached to the superconducting coil assembly so that it may be retracted about one-eighth of an inch breaking thermal contact of the sleeve assembly with the coil assembly's magnet cartridge and thermal shield while remaining hermetically connected to the coil assembly's vacuum enclosure. The coldhead's housing is attached to the sleeve assembly so that the coldhead's first and second stage make unconnected thermal contact with the sleeve assembly. By first retracting the sleeve assembly, the coldhead may be removed therefrom without room temperature air forming an ice ball on the surfaces of the sleeve assembly and without a heat load being transferred to quench the superconducting coil assembly. This permits continuous magnet operation using dual coldheads and dual sleeve assemblies.

Abstract: A circuit interruption device having a plurality of micromechanical switches mounted on a substrate in a parallel-series array. The array includes a plurality of line branches connected in parallel in a circuit line. Each of the line branches has at least two of the switches serially connected therein. The micromechanical switches each has a pair of contacts formed on the substrate, a bridging contact movably formed on the substrate, and an actuator for causing the bridging contact to move in and out of contact with the contacts. The bridging contact can be either a member slidably disposed in a channel formed on the substrate or member attached to an end of a cantilever having its other end attached to the substrate. The actuator is controlled by a trip device which is also mounted on the substrate. The trip device senses the current in the circuit line and causes the switches to open when a predetermined level of current in the line is exceeded.

Abstract: A locomotive diesel engine test assembly generates a once-per-cycle signal phased to the top dead center of a predetermined piston in its cylinder. A locomotive diesel engine crankcase door is hermetically attached to the crankcase so as to cover a camshaft located therein. An outer tube extends through and is hermetically and fixedly attached to the crankcase door, and an inner tube extends through and is hermetically and pivotably attached to the outer tube. A proximity sensor is attached to the inner tube and positioned near and generally perpendicular to the camshaft. A marker is attached to the circumference of the camshaft and is detectable by the proximity sensor once per revolution of the camshaft.

Abstract: A pancake magnetic resonance imaging (MRI) magnet having a superconductive coil assembly including a toroidal-shaped coil housing containing a superconductive main coil set and a radially spaced-apart superconductive supplemental coil set. The main coil set includes a first main coil located radially towards the circumferential outside surface which faces away from the bore, and the supplemental coil set includes three radially spaced-apart supplemental coils located radially towards the circumferential outside surface which faces towards the bore. The first main coil and the middle supplemental coil each carry an equal electric current in a first direction while the other two supplemental coils each carry the same electric current in the opposite direction. Such coil arrangement produces an imaging volume longitudinally wider than the longitudinal thickness of the magnet.

Abstract: Pulse width modulation is used to control the flow rate through a solenoid expansion valve in a refrigeration system. A first temperature sensor is disposed on the suction line, and a second temperature sensor is disposed in a compartment to be cooled. A controller is included for controlling the duty cycle of the pulse width modulated solenoid valve. The controller receives inputs from the two temperature sensors as a basis for controlling the duty cycle. The first temperature sensor can be located either inside or outside of the compartment. Preferred exterior locations include: immediately outside of the compartment, at the inlet of the compressor, at the inlet of the heat exchanger between the suction line and the liquid line, and at the outlet of the heat exchanger.

Abstract: A subassembly for an ice maker includes a double-sided ice cube tray having a housing located within the refrigerator freezer. The housing has a first side with spaced-apart first ice cube cavities facing upward and has a second side with spaced-apart second ice cube cavities facing downward. With frozen ice cubes attached to the second ice cube cavities, household water is delivered to the empty first ice cube cavities. The heat of the water causes the frozen ice cubes to become detached from the second ice cube cavities whereupon gravity causes them to fall into a storage bin below. After the water freezes in the first ice cube cavities, a mechanism rotates the housing one-half turn and the cycle is repeated.

Abstract: Pulse width modulation is used to control the flow rate through a solenoid expansion valve in a refrigeration system. A first temperature sensor is located near the evaporator inlet, and a second temperature sensor is disposed in a compartment to be cooled. A controller is included for controlling the duty cycle of the pulse width modulated solenoid valve. The controller receives inputs from the two temperature sensors and controls the valve duty cycle based on the difference of the two temperatures. The second temperature sensor is preferably located on the back wall of the compartment and can be adjacent to the compartment air inlet, adjacent to the compartment air outlet, or between the air inlet and air outlet.

Abstract: A noise source for an aircraft engine active noise cancellation system in which the resonant frequency of noise radiating structure is tuned to permit noise cancellation over a wide range of frequencies. The resonant frequency of the noise radiating structure is tuned by a plurality of drivers arranged to contact the noise radiating structure. Excitation of the drivers causes expansion or contraction of the drivers, thereby varying the edge loading applied to the noise radiating structure. The drivers are actuated by a controller which receives input of a feedback signal proportional to displacement of the noise radiating element and a signal corresponding to the blade passage frequency of the engine's fan. In response, the controller determines a control signal which is sent to the drivers, causing them to expand or contract. The noise radiating structure may be either the outer shroud of the engine or a ring mounted flush with an inner wall of the shroud or disposed in the interior of the shroud.

Abstract: A signal enhancement system for separating a composite diagnostic signal detected in a rotating machine into component signals representative of the contributions to the composite signal of a number of independent sources. The signal enhancement system includes at least one signal subtraction loop having a transducer which produces a reference signal based on the rotational speed of a rotating shaft in the machine and an adaptive filter connected to the transducer. The adaptive filter processes the reference signal to produce a component signal which closely approximates the contribution of the rotating shaft to the composite signal. A summer is also included which subtracts the component signal from the composite diagnostic signal to produce a second component signal. Both the first and second component signals are provided as outputs of the system.

Abstract: Transducer arrays are constructed using multiple layers of transducer elements, each layer of transducer elements having energy passages such as spaces to allow free passage of energy to or from transducer elements in another layer. Each transducing element performs the same transducing (energy conversion) as the other transducing elements. The transducer arrays may be detector arrays having scintillation materials for detection of x-ray or other high energy rays with each element operable to detect the same type of energy (e.g., x-ray, gamma ray, ultrasound, etc.) as the other elements. Multiple layering of the detector elements allows construction of a diced or mosaic detector array without restrictions upon the thickness of the individual elements which might otherwise result from the kerf width.

Abstract: A modular slab assembly for a face-pumped laser includes a slab module having top and bottom reflector segments, with first and second inner end caps joined thereto. A plurality of alignment keys are disposed between the inner end caps and the reflector segments for maintaining alignment therebetween, with the inner end caps being removably fastened to the reflector segments. The inner end caps have central apertures for supporting a slab tube, with a laser slab being disposed through the tube and supported at its ends by outer end caps removably fixedly joined to respective ones of the inner end caps. A pair of removable lamp modules are disposed on opposite sides of the slab module and contain lamps for exciting the laser slab.

Abstract: An optical fiber has a fiber core which includes a step index core portion and a graded index core portion located substantially around the step index core portion. The optical fiber also has a cladding located substantially around the graded index core portion and an outer jacket located substantially around the cladding. The optical fiber design allows high power laser transmission which minimizes modal-dispersion problems and delivers improved high power fiber-delivered beam quality.

Abstract: A system and method is provided for aligning a scanning surface of an inspection probe relative to a workpiece surface under inspection. The probe preferably includes at least three alignment eddy current elements, each producing a respective spacing indication electrical signal in accordance with a spacing between each alignment eddy current element and the workpiece. The system further comprises processing means which receives each spacing-indication electrical signal so as to generate data indicative of the relative alignment between the scanning surface of the probe and the workpiece surface. A controller is responsive to the alignment data for aligning the probe such that in operation the scanning surface thereof is substantially parallel relative to the workpiece surface. The probe can include inspection eddy current elements, in which case the alignment and the inspection eddy current elements can be fabricated to form an integral eddy current inspection probe.

Abstract: A magnetic resonance imaging (MRI) magnet having an annularly cylindrical-shaped vacuum enclosure with a longitudinal axis, first and second longitudinal ends, a first larger diameter bore extending from the first towards the second longitudinal end, and a second smaller diameter bore extending from the second longitudinal end to the first bore. First and second superconductive coils are placed in the vacuum enclosure with the first coil generally circumferentially surrounding the first bore and the second coil circumferentially surrounding the second bore, wherein the radial distance of the radially innermost portion of the second coil from the axis is smaller than the radius of the first bore. The first longitudinal end of the vacuum enclosure fits over a patient's shoulders with the patient's head at least partially passing through the first bore and extending into the second bore for MRI brain imaging.

Abstract: A noise source for an aircraft engine active noise cancellation system in which the resonant frequency of a noise radiating element is tuned to permit noise cancellation over a wide range of frequencies. The resonant frequency of the noise radiating element is tuned by an expandable ring embedded in the noise radiating element. Excitation of the ring causes expansion or contraction of the ring, thereby varying the stress in the noise radiating element. The ring is actuated by a controller which receives input of a feedback signal proportional to displacement of the noise radiating element and a signal corresponding to the blade passage frequency of the engine's fan. In response, the controller determines a control signal which is sent to the ring, causing the ring to expand or contract. Instead of a single ring embedded in the noise radiating panel, a first expandable ring can be bonded to one side of the noise radiating element, and a second expandable ring can be bonded to the other side.

Abstract: Pulse width modulation is used to control the flow rate through a solenoid expansion valve in a refrigeration system. A device for sensing suction line temperature is provided, and a controller is included for controlling the duty cycle of the pulse width modulated solenoid valve. The controller receives input from the suction line temperature sensing device as a basis for controlling the duty cycle. The suction line temperature sensing device may be a temperature sensor disposed on the suction line at the midpoint of the heat exchanger between the suction line and the liquid line. Alternatively, the suction line temperature sensing device may include a first temperature sensor disposed on the liquid line at one end of the heat exchanger and a second temperature sensor disposed on the liquid line at another end of the heat exchanger.

Abstract: A method for visualizing vector fields uses texture mapping for the vectors to create an animated vector field. Vectors are textured with one dimensional texture maps composed of alternating visible and invisible segments. Successively applied texture maps differ from each other in order to create a moving line effect on the vectors being visualized. A fading effect is further provided by varying the intensity of the visible segments.