Abstract: A method and apparatus for inspecting nonmetallic parts, including composite parts for, e.g. aircraft engines by quantifying their porosity, wherein a laser beam is directed to one side of the part to heat a portion thereof, with a delay being noted for the applied heat to transmit through said part to the opposite side thereof. An infrared radiometer (IR) is mounted to view such opposite side and to read (after such delay) the heat transmitted therethrough in the form of voltage (increase) readings. Such IR readings are taken at points across the part being inspected and the readings are then compared to a known data base of temperature change against vol. % porosity or the resulting calibrated porosity curve, to quantify the % porosity at various points on the sample. The inventive method can read or quantify porosity parts of simple geometry as well as of complex geometry, including engine housing flanges of small radii of curvature.

Abstract: This invention is directed to an expendable which includes an electronic circuit for introducing a simulated Doppler frequency shift. When dropped from an aircraft, the expendable is used to confuse hostile radar operations. In the past, the approach has been to use a high frequency electronic switch (PIN diode) and drive oscillator to change the impedance of the expendable antenna. This invention involves a simplification which combines the electronic switch and its drive oscillator into a single semiconductor component. By connecting a feedback circuit from the collector to the base of a high frequency transistor as well as to the two arms of the antenna, the antenna impedance is changed at the transistor oscillating frequency.

Abstract: A repetitively pulsed, high energy, closed cycle photolytic atomic iodine lasers operates at 1.315 microns. Using an iodine (I.sub.2) removal system for the photolyzed C.sub.3 F.sub.7 I laser fuel, more than 70 joules/pulse is output in the fundamental mode from a M=3 confocal unstable resonator at a 0.5 Hz repetition rate. The closed cycle iodine (I.sub.2) removal system consisted of a condensative-evaporative section, two Cu mesh I.sub.2 sections, and an internal turbo-molecular blower. This closed cycle system uses C.sub.3 F.sub.7 I gas at 10-60 torr absent of I.sub.2. The turbo-molecular blower is able to push high molecular weight gases at high velocities. The turbo-molecular blower is able to produce longitudinal flow velocities greater than 10 m/s through the 150 cm long by 7.5.times.7.5 cm.sup.2 cross sectional photolytic iodine gain region. In addition to the high energy output, the resulting 7-12 .mu.sec laser beam has a beam quality less than 1.

Abstract: Tetramethylammonium azide, N(CH.sub.3).sub.4 N.sub.3, is prepared by a new process per the present invention. In the prior art, preparation of such azide was by use of shock-sensitive starting materials, i.e. AgN.sub.3 and HN.sub.3. The method of the present invention provides a new method for making such azide at high purity, at room temperature, without the use of shock-sensitive materials.

Abstract: An apparatus for making aromatic heterocyclic polymeric fibers having enhanced compressive strength is disclosed. Individual polymeric fibers, while being made according to otherwise conventional methods, are full twisted as they are drawn from a spinnerette hole so that their internal fibrils and microfibrils become entangled. The twisting is performed before coagulation of the fibers. The entangled fibrils and microfibrils are believed to provide mutual support to adjacent fibrils/microfibrils to resist buckling under compression.

Abstract: An optical device which uses a heterojunction field effect detector (HFED) having wavelength selectivity through the use of ion-implantation, and a wavelength selective grating. The device incorporates a Grinsch layer structure with a single GaAs quantum well. The optical power from the lens couples into a guided mode. The absorbing region is the quantum well itself. In the operation of the HFED, a positive bias is applied to the gate, and the depleted GaAs quantum well below the gate absorbs the photons, generating electron-hole pairs. The photocarriers are separated by the electric field before recombination can occur. The photocurrent is then produced in the external circuit by appropriately biasing the device. For collecting the electrons, a positive bias is applied to both the source and drain contacts, which act as dual drain contacts. The holes are removed via the collector which is maintained at ground. To maximize the responsivity (i.e.

Abstract: A method is disclosed for establishing an optical link between two lasers via an optical fiber by directing the output from one laser through an optical fiber and into a second laser and vice vera. Before insertion into the lasers, the output from the respective fibers is phase conjugated in a double phase conjugate mirror. Thus, the disclosed method and apparatus provide a combination of fiber optics, used to transport the light from the lasers, and optical phase conjugation, used to compensate for fiber-induced distortions.

Abstract: The present invention is a humidity sensor which can be used in a radiosonde. The humidity sensor includes a heat sink attached to the radiosonde, a Peltier cooler attached to the heat sink, a carbon element with a thermistor attached therein or thereon, and a control means. The resistance of the carbon element is adjusted to a predetermined level to maintain a relative humidity of about 33, in particular. The control means monitors this resistance and adjusts the Peltier cooler accordingly. The thermistor responding to the temperature of the carbon element outputs a resistance indicative of the temperature on the sensor surface.

Abstract: A system and process are presented in which the factors of quality, cost, and access are integrated in such a manner as to provide a holistic description of the effectiveness of care at medical treatment facilities (MTFs). By using medical treatment data from a variety of computerized databases and incorporating patient perceptions of care through the use of surveys, the effectiveness of a particular facility's medical care can be compared to other medical care facilities. Deficiencies in performance are readily identified through this process, permitting goals and targets to be established that provide direction for medical administrators to enhance medical care at their treatment facilities. This approach is applicable to any set of medical care facilities, and also to just about any organized human endeavor involving quality, cost and access factors.

Abstract: A method for performing chemical warfare and similar cleanup activities and apparatus enabling the performance of such activity in high-temperature environments while maintaining safe and worker comfortable body temperatures. The disclosed method and apparatus rely on alternate periods of work and rest with the rest periods being additionally used for worker body temperature regulation such as cooldown. A portable temperature regulated liquid source is provided. Avoidance of worker encumbrance by personally-borne apparatus and the maintenance of non-tethered independent condition during work portions of the operating cycle provide advantages over the most closely related prior methods and apparatus. Human subject test results are also included.

Abstract: A system and a process for identifying three-dimensional coordinates and orientation to a robot. A pair of CCD video cameras are used to measure the position of a laser or other light source spot on the surface of a workpiece. The laser and cameras need not be fixed to each other, and the laser may be handheld. In operation, the light source provides a small spot of light centered on the location to be indicated to the robot. The spot of light is then located in the field of view of each of the cameras. Using the concept of stereo triangulation, the three-dimensional coordinates of the spot are calculated by a microcomputer. These coordinates are then transformed into a form which is recognizable by the robot. The spot of light from the object can also be generated by an emitter (such as an LED or Laser diode) which is fixed on the workpiece and stimulated by an energy source.

Abstract: A porous light-weight getter which collects particulate and molecular contaminates that is believed a significant improvement over the prior art is provided in which a metal mesh matrix is coated with a low-density porous aerogel. In the prior art bare metal mesh matrices have been employed as getters, which are subject to ablation from high-velocity contaminant particles. In the composite getter of the present invention, the low-density aerogel coating protects the enclosed metal matrix from ablation and also can attract and hold the incoming high-velocity particle. On its part, the metal mesh provides reinforcing support to the aerogel covering and also good thermal conductivity therein so that such covering can be cooled to the low temperatures that attract such contaminants. The invention further provides method for manufacture of the composite getters of the invention.

Abstract: An airborne radar warning receiver for track-while-scan radar including a first radar frequency receiver and logic circuitry for determining an increase in pulse rate frequency, second radar frequency receiver connected to a signal filter and an automatic gain control amplifier connected to the receiver and a logic circuitry connected to the amplifier and to the pulse rate frequency logic whereby the ratio is determined between the time from the start of scan until the radar beam illuminates the aircraft and the total scan time, thereby indicating the center of a search scan sector. A third radar frequency receiver connected to a signal filter and a logic circuitry connected to the receiver for indicating when signals are being radiated indicative of the launching of a radar controlled missile.

Abstract: An associative memory apparatus having a 2f Fourier transform optical correlation configuration wherein the correlation spots produced in the correlation plane are projected back by a mirror through the inverse Fourier transform lens and a phase correction reference image filter to produce the output image representing the best match between the input image and the associative memory reference images. A 4f Fourier transform embodiment projects the correlation spots forward through a second filter and transform means and the output image can be fed back to the input image display SLM to enhance the output image.

Abstract: A method for fabricating an LD aerogel reflector, including large space-based mirrors is provided wherein, a) an LD silica aerogel substrate at densities between 10-500 mg/cc is prepared, b) the surface of such aerogel substrate is polished to an optical quality surface, c) a dielectric planarization layer of SiO.sub.2 is applied to the so-polished substrate surface and d) one or more reflective layers (of e.g. Al/Y.sub.2 O.sub.3 coatings) are deposited on the planarization layer to form a lightweight reflector which includes an LD aerogel substrate that was not available before the invention hereof. Such LD aerogel substrates of the invention are lighter than ULE glass substrates for mirrors by a factor of up to 6 or more. Accordingly, given the payload constraints of launch vehicles, much larger reflectors made according to the invention, can be deployed in space than previously possible with heavier prior art mirror substrates.

Abstract: The disclosure provides a method for use in a robotic system for identifying fasteners used in aircraft and other applications. The fasteners include rivets (with no slots), bolts (with two slots) and screws with one or two slots. The method accepts as input a family of related signals which are known to contain symmetry. By computing the mean variance of the zero-meaned cross-correlation signals, the method automatically selects those signals which contain pertinent information while disregarding those signals which do not. The accepted signals are then used to create a composite reference signal which can be used to determine the particular fastener type.

Abstract: In a gas turbine engine a method for thrust variation with reduced compressor RPM excursion is provided in two modes which includes adjusting pivotable compressor vanes mounted upstream of compressor rotor blades, ahead of the conventional vane schedule therefor in a closed loop fashion, responsive to compressor corrected RPM, so as to adjust the fuel demand and engine thrust thereof while maintaining relatively high scheduled compressor corrected RPM scheduled as a function of fan corrected RPM while retaining the conventional method of fuel flow scheduling. Thus mode 1 of the invention adjusts the compressor vanes in advance of the conventional schedule therefor, e.g. pre-closes them on the deceleration side of the Bodie transient and appropriately opens them on the acceleration side of such transient subject to closed loop monitoring of the corrected compressor RPM and being guided thereby so as to result in reduced excursion in such RPM, during both legs of such transient.

Abstract: The method of this invention simulates a 16-bit color composite satellite picture upon an 8-bit color display system, a simulated picture being of substantially equal quality as a 16-bit picture, a simulated picture can be placed on a personal computer system or workstation having an 8-bit color display system. The two 8-bit images for creating the 16-bit color picture are combined in a unique manner so that a resulting 8-bit color composite picture is presented on the 8-bit color display system. The 8-bit picture produced generally has greater contrast than the picture produced on the 16 bit system.

Abstract: The invention comprises processes and heterostructure products defining silicon on insulator waveguides (80, 88, 90, 106, 112, 120, 122) that are suitable for use with light in the 1.3, 1.6 .mu.m or greater wavelengths. Silicon is deposited on an insulator layer 12 on a crystalline substrate 10 and grown or regrown in crystalline form. The silicon is then etched or formed into a waveguide structures.

Abstract: The unauthorized separation of a second member such as a door with respect to a first member affixed to a computer frame and the subsequent replacement of the initial position of the door creates a change of state of a square loop magnetic member integral with the computer frame. This change of state can be monitored from time to time to indicate an unauthorized opening of the door.