Abstract: In one embodiment, a method of operating an implantable pulse generator comprises: providing power to a voltage converter at a first voltage level; outputting a second voltage level by the voltage converter, the second voltage level being a variable voltage level that is controlled by a control signal provided to the voltage converter, the second voltage level being provided to pulse generating circuitry of the implantable pulse generator, the second voltage level being selectable from a plurality of voltages including non-integer multiples of the first voltage level; generating pulses by the pulse generating circuitry, the pulse generating circuitry including current control circuitry for controlling the pulses to cause the pulses to provide substantially constant current to tissue of the patient; and applying at least two different control signals to the voltage converter during individual pulses to provide successively increasing voltages to the pulse generating circuitry during a respective pulse.

Abstract: A system and method for inspecting a grain size of a cast alloy component while maintaining the structural integrity of the cast alloy component is disclosed. The method includes recording a radiographic image of the component, identifying areas of the component to be inspected, and locating one or more lines having a pre-determined length on the radiographic image at an area to be inspected. Then, a total number of intersections with the one or more lines are determined and an average grain size is calculated.

Abstract: In one embodiment, a method of operating an implantable pulse generator comprises: providing power to a voltage converter at a first voltage level; outputting a second voltage level by the voltage converter, the second voltage level being a variable voltage level that is controlled by a control signal provided to the voltage converter, the second voltage level being provided to pulse generating circuitry of the implantable pulse generator, the second voltage level being selectable from a plurality of voltages including non-integer multiples of the first voltage level; generating pulses by the pulse generating circuitry, the pulse generating circuitry including current control circuitry for controlling the pulses to cause the pulses to provide substantially constant current to tissue of the patient; and applying at least two different control signals to the voltage converter during individual pulses to provide successively increasing voltages to the pulse generating circuitry during a respective pulse.

Abstract: An investment casting method using a pattern material with substantially spherical filler particulates is used to produce investment cast components with iproved surface quality, reduced finishing costs, and reduced core breakage. The pattern material comprises substantially spherical particles within the particle size range of about 10 microns to about 70 microns particle diameter, the use of which reduces the number of random, localized surface depressions and pits to improve pattern surface texture and uniformity. Patterns so formed inpart the same improvements to the surface of subsequent investment cast components. The resulting castings exbibit improved as-cast surface finish and reduced random, localized surface pitting, thereby reducing or eliminating expensive post casting surface finishing operations. Moreover, the spherical morphology of the filler particulates reduces injection pressures to fill a pattern die cavity as compared to non-spherical filler particulates.

Abstract: An investment casting method using a pattern material with substantially spherical filler particulates is used to produce investment cast components with improved surface quality, reduced finishing costs, and reduced core breakage. The pattern material comprises substantially spherical particles within the particle size range of about 10 microns to about 70 microns particle diameter, the use of which reduces the number of random, localized surface depressions and pits to improve pattern surface texture and uniformity. Patterns so formed impart the same improvements to the surface of subsequent investment cast components. The resulting castings exhibit improved as-cast surface finish and reduced random, localized surface pitting, thereby reducing or eliminating expensive post casting surface finishing operations. Moreover, the spherical morphology of the filler particulates reduces injection pressures to fill a pattern die cavity as compared to non-spherical filler particulates.

Abstract: The pattern material with substantially spherical filler particulates is used to produce investment cast components with improved surface quality, reduced finishing costs, and reduced core breakage. The pattern material comprises substantially spherical particles within the particle size range of about 10 microns to about 70 microns particle diameter, the use of which reduces the number of random, localized surface depressions and pits to improve pattern surface texture and uniformity. Patterns so formed inpart the same improvements to the surface of subsequent investment cast components. The resulting castings exhibit improved as-cast surface finish and reduced random, localized surface pitting, thereby reducing or eliminating expensive post casting surface finishing operations. Moreover, the spherical morphology of the filler particulates reduces injection pressures to fill a pattern die cavity as compared to non-spherical filler particulates.

Abstract: The oxidation resistance of a superalloy casting such as an equiaxed, directionally solidified, or single crystal casting, is improved by melting, pouring, or casting the alloy so as to react with a magnesium or calcium-bearing ceramic material. Magnesium or calcium is introduced into the alloy through a controlled reaction between the alloy and the magnesium or calcium-bearing ceramic material.

Abstract: A process is provided for forming activated carbon from coal in the particulate state. The coal is first dried at a temperature sufficiently high to effect removal of moisture therefrom but below the temperature at which contained volatile matter vaporizes. The dried coal is then heated to an elevated temperature in a substantially non-oxidizing atmosphere at substantially atmospheric pressure sufficient to volatilize and remove the contained volatile matter and produce a char thereof and the char thereafter subjected to hydrogenation at an elevated temperature and pressure for a time sufficient to form activated carbon characterized by a BET surface area of at least about 200 m.sup.2 /g and an iodine number of at least about 400.

Abstract: A cover plate for a cooling fan motor includes a heat shield portion spaced from the motor and a deflector portion extending beyond the motor. The deflector portion redirects axial discharge airflow across the motor to provide cooling, thereby improving the life of the motor bearings and the operating efficiency of the motor.