Abstract: An AB2 monomer of the formula: wherein Z is selected from the group consisting of —OH, —SH and —NH2HCl, is useful for the preparation of hyperbranched polybenzoxazoles.

Abstract: A new process for making a neodymium gallate (NGO) surface layer on the inside surface of a protective outer sheath of nickel surrounding a core of yttrium-based copper oxide (YBCO) superconductor material permits manufacture of very high performance superconducting wire and tape. The NGO surface layer acts as a diffusion barrier to prevent diffusion of nickel into the YBCO during high temperature melt-processing. The NGO is applied, preferably by slurry casting, to a flat strip of solid nickel and then sintered at temperatures above about 1000° C. The sintering binds the NGO to the nickel strip and fixes it so that it will not react chemically with the YBCO during later melt-processing. The nickel strip and NGO diffusion barrier layer are next rolled into a trough and YBCO ceramic powder inserted inside the trough. The trough is then further rolled into a tube leaving an open seam for oxygen to penetrate during the oxygen anneal procedure of melt-processing.

Abstract: A cavity ring-down spectroscopy device and method suitable for materials with low and high absorption coefficients. An optical signal introduced into an optical cavity resonates through a length of fiber amplifier coupled to the optical cavity. The optical signal resonates through a fiber amplifier active section resulting in a gain compensating for optical losses. The gain obtained by use of the fiber amplifier is then modulated between two predetermined levels. By virtue of employing an optical fiber, the cavity ring down spectroscopy device and method is insensitive to misalignment and therefore iminently capable of portability.

Abstract: A method of imparting birefringence in a III-V compound semiconductor for sustaining the non linear optical process of second harmonic generation, a birefringent III-V compound semiconductor, and a product of the process are described.

Abstract: A self-polymerizable AB2 monomer of the formula The resulting AB2 monomer can be polymerized to afford high molecular, low viscosity hyperbranched ether-ketone-imide polymer having repeating units with hydroxyl endgroups.

Abstract: A dynamic programming network integrating sensor management, sensor fusion, and an application in a seamless structure in which these functions are mutually dependent and develop autonomously and concomitantly with experience. The dynamic programming network autonomously divides these functions into multiple subtasks that it can assign to the processors of a fine-grained parallel computer. As the number of processors available for these subtasks increases the network may attain its objective more efficiently. This architecture confers the greatest advantage in feature-rich applications such as identification of targets in synthetic aperture radar, visual, and infrared images. The design can be extended, however, to such diverse and general applications as control problems and machine intelligence.

Abstract: A solid state laser device made from a nonlinear optic quaternary alloy of Silver, Gallium, Selenium and Tellurium semiconductor material or Silver, Gallium, Sulfur and Tellurium semiconductor material. The Tellurium component in each alloy provides quaternary alloying anion modification of an underlying ternary semiconductor crystal and achieves tuning of the birefringence and tuning of the wavelength passband of the semiconductor material. The tuned quaternary alloy enables beam walkoff-free noncritical phase match operation of the laser device including use of a phase match angle supporting optimum use of the material's nonlinear properties, maximized useful length of the material crystal, room temperature wavelength changing operation, significantly increased second order nonlinear susceptibility, a factor of ten reduction in the walk-off angle and photon energy conversion efficiencies several times those usually achieved.

Abstract: Formation of for example yttria stabilized zirconia films of significant 001 orientation on a variety of substrates including amorphous material and room temperature limited material is disclosed. The yttria stabilized zirconia film formation is achieved using pulsed laser ablation of a polycrystalline yttria stabilized zirconia target source while the substrate is electrically biased, disposed at a selected angle and maintained at substantially room temperature in the presence of an argon atmosphere. The film formation uses low bias voltage, requires no ion beam apparatus and employs low temperatures sufficient only to enable process stabilization. Film formation is accomplished in a step sequence wherein each step responds to temporal and spatial component segregations occurring in a laser-ablated ion plume.

Abstract: A wing mounted yaw control device is disclosed. The wing mounted yaw control device includes a spoiler hingedly mounted on a first wing surface and a deflector hingedly mounted on a second wing surface. A deployment mechanism is provided to effect simultaneous deployment of the spoiler and deflector. During operation, the spoiler and deflector are selectively deployed in order to impart an unbalanced drag force on one wing, thereby imparting the desired yaw moment to an aircraft in flight.

Abstract: Certain transient events such as hard landings, high g-rate turns, thermal conditions, and high turbulence may cause rubbing events inside the gas turbine that result from the flexure of the engine shafts. In order to prevent permanent damage to the engine or operational interference, brush seals are used such that the tips of the stator blades and the tips of the respective opposing annular brush seals, and the tips of the rotor blades and the tips of the respective opposing annular brush seals define substantial radial clearances that provide gaps that remain open under all regular and normal operating conditions of the gas engine.

Abstract: A weaker signal receiving system inclusive of stronger nearby-sourced interference signal cancellation capability. Stronger interference signal cancellation is accomplished by actively canceling or subtracting from the received signal an intermediate signal in which the weaker signal has been attenuated but the stronger signal remains. Attenuation of the weaker signal in this intermediate signal is accomplished in a feedback loop arrangement by an amplitude-responsive signal processing element embodied from for example a ferrite material such as yttrium iron garnet disposed in a physical wave propagating and wave amplitude sensitive film. The cancellation or subtracting is accomplished using received signals and without need for a direct output sample of the stronger signal at its source. Military aircraft use of the disclosed system in the microwave and other spectral regions with transmission mode as opposed to reflection mode signal amplitude discrimination by the ferrite device is included.

Abstract: System and method for actively canceling the acoustic noise generated by changes in the electric current within the gradient coils of a magnetic resonance imager based on the finding that the acoustic noise in the magnetic resonance imager is highly periodic but that the period of the magnetic resonance imager noise changes substantially during a scan. The acoustic noise signal is measured at the ears of a patient undergoing a magnetic resonance imaging, delayed by a variable number of samples and the resulting signal is subtracted from the acoustic noise signal. Magnetic resonance imaging noise cancellation occurs at the level of 20 decibels or more.

Abstract: An orthogonal functional basis method for function approximation is disclosed. Starting with the orthogonal least squares method, a new subset selection method for selecting a set of appropriate basis functions is explained where, instead of picking a subset from a given functional basis, the subset is selected from a combination of functional basis evolved from a set of heterogeneous basis functions. The method results in a more efficient neural network.

Abstract: A system for communicating hardened, buried target arrival-related data from an airborne warhead device to a remote mission analysis location is disclosed. The communicated information especially relates to impact deceleration events encountered by a hardened target penetration warhead, events arising from the warhead impacting with the earth and then with one or more layers of hardening material such as concrete disposed in or adjacent a subterranean target. Verification of warhead detonation may also be included in the communicated data. The system includes ultra high radio frequency communication from the subterranean warhead to a repeater apparatus disposed at or above the point of warhead earth impact followed by conventional signal relaying of the collected warhead experience data from the repeater to a remote mission analysis facility.

Abstract: A high power density alkaline electrochemical capacitor cell includes a pair of titanium nitride powder electrodes fabricated by subjecting titanium hydride powder to a controlled flow of ammonia vapor. A porous separating membrane for containing an electrolyte is attached to a first surface of the pair of powder electrodes. A conductive termination is attached to the second side of each of the powder electrodes. The electrodes have a high surface area and are electrochemically stable in strong alkaline electrolyte. The capacitor cell can be hermetically sealed and is capable of long-term cyclical operation over a wide range of operating temperatures (−55° C. to +100° C.) while providing high-density energy storage.

Abstract: A switch modulated low duty cycle low energy mass limited radio frequency beacon system for locating spent, un-exploded or experimental munitions projectiles in a large open-air test range or within a dirt backstop. The disclosed locator beacon is mounted on a rear portion of a projectile before launch and includes a protective (and antenna length-shortening) resin dielectric material housing in which locator beacon circuit components are contained and immunized against high G forces by a combination of component supporting, energy deflecting and energy absorbing protective arrangements.

Abstract: An electronic warfare radio receiver of the monobit type wherein the signal processing circuitry, including a bandpass filter array, analog to digital converter circuit and Fourier transformation circuit, are located in a plurality of parallel-disposed but isolated receiver channels. The parallel disposed receiver channels limit interference between received signals and enable the customary processing of two simultaneous input signals of differing signal strength in each receiver channel; this increases the number of simultaneous input signals processable by a factor equaling the number of receiver channels used. Single chip embodiment of the receiver is disclosed thereby tending to compensate for the added complexity of the channelized processing. Signals falling in digital filter overlap regions are addressed by the invention.

Abstract: An aircraft weapons bay high frequency acoustic suppression apparatus is disclosed. The apparatus includes an extendable spoiler retractably received within an aircraft weapons bay. An injector unit is received within the spoiler for injecting high frequency pulses of pressurized gas into the airstream. The injector unit includes a resonance tube in outlet fluid communication with an nozzle. The pulsating output of the resonance tube perturbs the flow of pressurized gas in the nozzle, effectively breaking it up into discrete slugs or pulses which then exit the nozzle and enter the airstream. The high frequency perturbation of the airflow across the weapons bay, created by the aircraft weapons bay high frequency acoustic suppression apparatus of the present invention effectively suppresses undesirable acoustic resonance within the open weapons bay.

Abstract: A differential property sensitive acoustic lens for non-destructive materials evaluation is described which in a preferred embodiment comprises first and second substantially semicylindrical shaped portions of fused silica disposed in closely spaced relationship along an axial plane, a substantially spherical depression defined in one end of each semicylindrical portion and a flat defined on each semicylindrical portion at the other end, a piezoelectric transducer attached to the flat of each semicylindrical portion, and a paraffin coated aluminum film of preselected thickness disposed between and in laminar contact with the semicylindrical portions for preventing acoustic and electrical cross talk between the transducers and between the semicylindrical portions.

Abstract: In accordance with the foregoing principles and objects of the invention, the mitigation of fires in machinery enclosures is achieved by strategic placement of thin narrow strips of intumescent material within the ventilated space between the machinery and a housing enclosing the machinery, whereby, in the event of a fire, the resulting flame contacts the intumescent material causing it to swell and to effectively block air flow through the ventilated space.