Abstract: An abrasion-resistant article and method for making is disclosed. The article includes a plastic substrate and a gradational coating applied by plasma-enhanced chemical vapor deposition to the surface thereof.

Abstract: A composite comprised of a ceramic matrix and a plurality of layers of boron nitride coated fibrous material, said coated fibrous material comprising at least about 10% by volume of said composite, and said matrix having a thermal expansion coefficient which ranges from lower than that of said coated fibrous material to less than about 15% higher than that of said coated fibrous material.

Abstract: Aromatic thermoplastic polyarylates containing structural units derived from a bisphenol of cyclohexanone, preferably 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane, and an aromatic dicarboxylic acid or mixture of such acids, are provided which exhibit improved oxygen barrier properties.

Abstract: A. parasiticus is employed to hydroxylate biphenyls or terphenyls. The hydroxylation reaction is enhanced by gradually adding a carbon source to the culture medium-reaction medium, preferably in an amount to maintain the ammonium level below 300 ppm. during the bioconversion phase. Employment of a mutant strain of A. parasiticus which was isolated following ultraviolet light mutagenesis to reduce its tendency to produce aflatoxins is preferred.

Abstract: A. parasiticus is employed to hydroxylate 2'-hydroxyterphenyl compounds to terphenyltriols, which can be used to form branched polycarbonates. The hydroxylation reaction is enhanced by maintaining a sufficient amount of a carbon source in the culture medium-reaction medium to maintain the ammonium level below 300 ppm. during the bioconversion phase. Employment of a mutant strain of A. parasiticus which was isolated following ultraviolet light mutagenesis to reduce its tendency to produce aflatoxins is preferred.

Abstract: A nozzle holder and sensor for a pressure pot peening system is disclosed. The holder includes a 90.degree. bend which is provided so that substantially the entire momentum of the mass of shot and air ejected from the nozzle can be sensed by the sensor and mass of shot and air ejected is not adversely affected if the hose from the shot peening system is moved. Also the holder can be oriented into a variety of positions and locations.

Abstract: A transfer tube is produced comprised of a high density ceramic oxide tube having directly bonded to its outer surface wall a low density ceramic oxide shell.

Abstract: A general architecture to correct conversion errors of a multi-stage, pipelined subranging analog-to-digital (A/D) converter includes cascaded stages, each stage generating a binary conversion signal representing the nearest quantized level below that of the analog input signal and a residual analog signal applied to the next conversion stage. The binary conversion signal from each stage addresses individual or common look-up tables providing a compensated binary signal selected to compensate for nonidealities of the A/D converter components. The compensated binary signals from the look-up tables provide a corrected output signal when summed together. A simple method of calibration for the A/D converter makes use of a least-mean-squared adaptation algorithm. The A/D converter accommodates practical circuit nonidealities such as component mismatching, gain error and voltage offsets, and handles high levels of amplifier nonlinearity.

Abstract: Apparatus for testing data conversion/transfer functions in each of a plurality N of channels of a vibratory energy imaging system includes a multiplexer for providing, to an addressable memory having a plurality of L=2.sup.M locations in each of which a data word of B bits can be stored, a selected one of an input data word and a test data word, each of which can address one of the L locations of the memory means. The address multiplexer facilitates retrieval from memory of a B-bit data word having a value selected to implement a selected function for that channel, so that comparision of data from the selected test address with the data which has been sent to that location for storage, will indicate if proper data is stored for carrying out the designated function.

Abstract: Parallel accumulation of the density functions of image picture elements is done for a number of elements located at the same radial distance from the axis of rotation for the fan-beam scanner. This allows the computation of weighting factor to be done in common for these elements, as well as the computation of interpolation coefficients for ray sums not registering exactly with x-ray detectors.

Abstract: A molding system utilizes a cold mold with a large thermal mass and contoured thin mold inserts with a low thermal mass. A composite sheet blank of glass fibers in a thermoplastic matrix resin is placed between the inserts, heated and then transported to the cold mold. The composite sheet is pressed in the cold mold between the mold inserts to flow form and then cool the part. The mold inserts keep the surfaces of the composite sheet hot during the forming process, thereby enabling the matrix resin to flow and form smooth surfaces.

Abstract: A starting aid for an electrodeless high intensity discharge (HID) lamp comprises a spiral starting electrode which, at least during lamp starting, conforms to the shape of the arc tube so as to provide a relatively high capacitive starting current upon receipt of a radio frequency starting signal, resulting in a rapid transition from a glow discharge to a high intensity solenoidal discharge. At least one turn of the spiral starting electrode is preferably in contact with the portion of the arc tube nearest the arc discharge to be formed and is oriented so as to provide a capacitive starting current that flows in substantially the same location as the arc discharge to further ease lamp starting. In one embodiment, the spiral starting aid comprises first and second coil portions. The first coil portion conforms to the shape of the arc tube and has at least one turn disposed nearest the portion of the arc tube where the arc discharge is to be formed.

Abstract: Apparatus for providing a desired output signal as a function of a single-valued input signal in an electronic system, includes: an addressable memory, having a plurality L locations, each for storage of a data word of B bits; a circuit for storing in each of the L locations of the memory means a B-bit data word having a value selected to provide a particular output value; and circuitry for converting a present single-valued increment of input signal to a unique address, within the range of allowable locations of the memory, to cause each increment of input signal to select the associated one of the L data word locations, from which to output corresponding data.

Abstract: A ballast for an electrodeless high intensity discharge lamp comprises a Class-D power amplifier including an integrated tuning capacitor network and heat sink. A series blocking/tuning capacitor and a parallel tuning capacitor are integrated by sharing a common capacitor plate. The metal plates of the parallel tuning capacitor also comprise heat sink planes to remove excess heat from the excitation coil of the lamp. Heat sink fins are affixed to the plates of the parallel capacitor. Efficiency is maximized by matching the impedance of the ballast load network.

Abstract: An apparatus and method for controlling the powder deposition and deposit pattern in a plasma spray process are provided in which an infrared imaging detector and associated processors are employed to provide an image of the temperature distribution of the deposit and to provide an identification of the impact point of the most recent powder deposit, and in which a cyclone separator or other device is used to modulate the flow rate of the carrier gas in which the powder is entrained at the point where the powder and gas are injected into a plasma plume, in order to move the impact point of the powder from the sensed location to a desired location. An injector tube is provided in a cross-flow injection system which may be sized to compensate for variations in the desired injection velocities of particles of different sizes, and the variations in the rate at which such particles are accelerated in the injection tube.

Abstract: Respective processors for pairs of photodetecting elements are included in an imager used for sensing hologram fringe patterns in an optical interferometer. These processors remove the direct-current pedestal from in-phase and quadrature-phase field images, then perform partial correlations of the resulting field images on a pixel-by-pixel basis, and then sum the partial correlations to complete the image correlation process and to provide imager output signal or the basis therefor. This localized processing greatly reduces the number of samples that have to be brought out of the imager each frame when the imager is used in an optical interferometer to detect phase modulation in an optical signal, allowing for increased frame rates in accordance with a further aspect of the invention. Image correlation is done according to a novel algorithm that avoids actually having to multiply together correspondingly located pixels in each pair of successive fields forming a successive non-overlapping frame.

Abstract: A method for controlling a power converter and an associated auxiliary commutation circuit ensures soft-switching of all switching devices employed therein. Such a power converter includes an inverter with at least two main switching devices per phase. Across each main switching device are connected an antiparallel diode and a relatively large snubber capacitor. The auxiliary resonant commutation circuit comprises two antiparallel-coupled auxiliary switching devices coupled in series with a resonant circuit including an inductor and the snubber capacitors. The gating and conduction times of the main and auxiliary switching devices are controlled so as to add boosting energy to the resonant operation, thus ensuring that the inverter output voltage at least reaches the positive and negative inverter rail voltages during each resonant commutation cycle. As a result, the control achieves commutation of the converter pole with substantially no switching losses.

Abstract: A superconductive foil and a first and second foil of current conducting material. The first and second foil are soldered symmetrically about said superconductive foil forming a superconductive tape. The tape is wound in helical layers forming a coil. Adjacent turns of the tape are electrically insulated from one another. A strip of electrically conductive foil is situated between layers of tape and electrically isolated therefrom. The strip of electrically conductive foil encloses the inner layers of the tape, with the ends of the strip joined together to form an electrically conductive loop. The coil is epoxy resin impregnated.

Abstract: A high-frequency capacitor includes first and second conductive members, each having a plurality of U-shaped metal plates disposed parallel to each other and a terminal plate coupled between the ends thereof. The metal plates of the first and second conductive members are interleaved, and a dielectric material is disposed between the adjacent metal plates. The result is a low-inductance capacitor suitable for use in a high-frequency electronic circuit, such as an electrodeless high intensity discharge (HID) lamp ballast. Furthermore, such acapacitor may be suitably integrated with a heat sink in an electrodeless HID lamp ballast.

Abstract: A TiAl composition is prepared to have high strength, high oxidation resistance and to have acceptable ductility by altering the atomic ratio of the titanium and aluminum to have what has been found to be a highly desirable effective aluminum concentration by addition of chromium and silicon according to the approximate formula Ti.sub.48 Al.sub.48 Cr.sub.2 Si.sub.2.