Abstract: A hierarchical object recognition method for aggregation, interpretation and classification of information from multiple sensor sources on the detection feature attribute level. The system extracts information derived from each sensor source to obtain detections and their feature attributes. At least two processing streams, one for each sensor source, are provided for converting the detections and their feature attributes into hypotheses on identity and class of detected objects. The detections are shared and combined between the two processing streams using hierarchical information fusion algorithms to determine which ones of the hypotheses on identity and class of detected objects have sufficient probabilities for classifying the information.

Abstract: A compact diode pumped laser including a nonuniform, single-or double-sided diode pumped laser head and a polarization output coupled (POC) resonator. The POC resonator employs reflections from two opposing uncrossed roof prism mirrors to produce a uniform near field and far field beam with diffraction or near diffraction limited quality. The single laser head particularly includes a laser rod, a sapphire envelope located about the rod, an area of antireflection coating located on the sapphire envelope between the rod and the diode array, and a high reflectivity nickel-plated indium layer located on the sapphire envelope on the surface thereof outside of the area of antireflection coating.

Abstract: A multilayer microelectronic module assembly has at least two planar module structures, in the form of boards lying parallel to each other and which must be electrically interconnected. Each planar module structure has electronic circuitry thereon and electrical interconnect locations in registry with corresponding electrical interconnect locations on the adjacent planar module structure. The electrical interconnections are accomplished by closely spaced direct electrical interconnectors extending between the respective electrical interconnection locations on the adjacent planar module structures. Each module assembly is preferably affixed to a support. Multiple supports are arranged parallel to each other and electrically interconnected by similar direct electrical interconnectors.

Abstract: A computationally efficient missile detection and tracking system, operating on data samples from a focal plane assembly (FPA) of an electro-optical sensor which is observing the earth and space, detects missiles, aircraft, resident space objects or other objects in the presence of background clutter, determines missile types and estimates missile position and velocity components in an inertial reference frame. Digitized samples from an array of electro-optical detectors which are viewing the earth and/or space are processed to detect and track missiles, aircraft and resident space objects. Streak detection is used for this purpose, where the target is separated from a background scene by exploiting target motion relative to the background scene. This processing system provides superior performance and simplified implementation as compared to conventional methods. The weight and power of a computer which can implement the processing system is much reduced as compared to conventional implementation.

Abstract: A linear compressor (60) includes a reciprocating piston (20) for varying the volume of a compression chamber (12). A moving coil motor (26) causes the piston (20) to reciprocate against the force of an integrally machined double-helix spring (62) about a position in which the spring (62) is in a free state. The spring (62) includes a retainer (72) which is attached to the piston (20), a fixed flange (66) and two resilient helical members (78,80) which extend between the flange (66) and retainer (72) along a longitudinal axis (82). The helical members (78,80) are configured such that lateral reaction forces thereof are mutually canceling. The helical members (78,80) have the same twist direction, are interspersed with each other along the longitudinal axis (82) and are rotationally displaced from each other about the longitudinal axis (82) by substantially 180.degree..

Abstract: A large, monolithic sapphire structure for use in mid-IR military applications, such as, for example, a window or screen for radar detection equipment. The structure is made by bonding together two or more smaller sapphire panes by a method including the steps of coating a surface of each of the panes with a magnesia vapor and contacting the magnesia-coated surfaces with each other in the presence of a hydrogen-containing gas at a temperature (e.g., about 1500.degree. C. and 2000.degree. C.) and for a time period (e.g., about 45 minutes to about ten hours) sufficient to form a continuous magnesia-alumina spinel interlayer bond between the panes.

Abstract: An improved digital fluxgate magnetometer that uses digital logic and a high resolution digital to analog converter to digitize a magnetic signal for use by signal processing algorithms. The magnetometer includes an oscillator that outputs an oscillator signal and a magnetic fluxgate sensor having a drive coil coupled to the oscillator, a feedback coil, and a sense coil. An analog multiplier is coupled to the sense coil and the oscillator and outputs a signal to an analog low pass filter. A comparator is coupled to the analog multiplier, and a register is coupled to the comparator and outputs a logical 1 or a logical 0 in accordance with the output of the comparator. A digital filter receives the output of the register and produces a digital output of the digital fluxgate magnetometer. A high resolution digital to analog converter is coupled between the register and the feedback coil of the magnetic fluxgate sensor in a feedback loop of the sensor.

Abstract: A window structure includes a first window layer including a zinc sulfide substrate coated on each side with an antireflective coating, and a second window layer including a sapphire substrate coated on each side with an antireflective coating. The two window layers are bonded together in a facing-but-spaced-apart relation by an infrared-transparent adhesive layer, preferably a silicone rubber. The window is placed into the wall of a sensor housing that contains an infrared sensor.

Abstract: A corona discharge pollutant destruction reactor employs two or more electrodes to enhance the effective corona discharge treatment volume by distributing a varying electric field pattern over the reactor's interior chamber. Appropriate delay circuitry allows the inner electrodes to be driven out of phase with each other by a sinusoidal voltage waveform, or corona producing voltage pulses to be cyclically supplied to the inner electrodes in sequence, preferably without overlapping the pulses.

Abstract: A projectile is propelled from a location in air, through an air/water interface, and toward a submerged underwater object. The projectile includes a forward end that forms a cavitation void around the projectile in water, avoiding water drag on the remainder of the projectile. The projectile further includes an outwardly flared or finned rearward end that aerodynamically stabilizes the projectile in air and flare stabilizes it in water, in each case against yaw.

Abstract: A flexible, electrically-conductive, one-component epoxy adhesive composition and method for making the same are provided. The present adhesive composition comprises: (a) at least one polyepoxide resin having a hardness not exceeding a durometer Shore D reading of about 45 when cured with a stoichiometric amount of diethylene triamine; (b) a substantially stoichiometric amount of curing agent including at least one amine-terminated butadiene-acrylonitrile polymer; and (c) an electrically-conductive filler. The epoxy adhesive, upon cure, has a volume resistivity not exceeding about 10.sup.-3 ohm-cm at room temperature and a drop resistance such that a 6-mil-thick (0.015 cm) bond effected by the adhesive can withstand at least six 60-inch (152 cm) drops onto a hard surface. Optional components in the epoxy adhesive include secondary rigid and semi-rigid epoxy resins, secondary amine curing agents, non-reactive flexibilizers, diluents, and processing aids.

Abstract: A ceramic waveguide filter made from a monolithic block of dielectric ceramic material which has longitudinally spaced resonators is described. Resonant structures having a grounded portion and ungrounded portion, each of the resonant structures being inductively coupled at the ungrounded portion describe the electrical schematic which corresponds to the waveguide filter. The positioning of the input and output on the block of dielectric ceramic material define a passband and also create a shunt resonant section. The shunt resonant section is associated with a shunt zero in the electrical schematic of the waveguide filter. Finally, the dielectric block of ceramic is mostly coated with an electrically conductive coating material with the exception of an uncoated area immediately surrounding the input and output.

Abstract: A modular enclosure system particularly suited for use aboard a ship comprises a modular enclosure which is easily installed into and removed from an exoskeletal frame that is shock-mounted to a fixed surface, such as the deck of a ship. An enclosure is installed by placing it within a respective frame via complementary guide rails. A securing mechanism locks the enclosure into place within the frame, and an ejection mechanism enables an enclosure to be easily removed for purposes of maintenance, repair or reconfiguration, or in the event of an emergency. The enclosures are preferably water-tight and float if ejected into the sea. Rubberized boots surrounding all points of entry enhance the survivability of the enclosures in a nuclear/biological/chemical (NBC) environment. Shock-mounting the frames to the deck eliminates the need to shock-mount individual pieces of equipment and enables the use of cheaper and more readily available commercial off-the-shelf equipment.

Abstract: A system and a method of designing and mechanical packaging of pumped laser resonator elements to minimize their size. All the elements of the compact pumped laser resonator assembly are placed on a monolithic block mount, which substitutes and functions as a laser diode heatsink, a laser resonator cavity mount, and an optical bench. The laser optical cavity has a plurality of bends, in order to decrease the size of the assembly, and the laser resonator optical elements include fold prisms, a reflector, a retroreflector and an intracavity optical Q-switch. A miniaturized diode array pumped laser resonator assembly using a miniature monolithic block mount may have a volume of less than one cubic inch and dimensions less than or equal to about 30 mm.times.25 mm.times.13 mm in metric units, and may weigh less than two ounces or 56 g, while providing a laser power of more than 1 mJ, thereby creating a very small but highly powerful pumped laser resonator assembly.

Abstract: A window is made of a curved piece of a transparent material having a front surface and a back surface. At least one of the front surface and the back surface has a shape which is a segment of a convex aspheric shape rotated about a center, otherwise known as a torus.

Abstract: A process is provided for preparing mixed metal oxide materials having improved leakage characteristics when formed into a capacitor. The process comprises: (a) preparing a solution of a liquid precursor of the mixed metal oxide materials having a given composition in a water-immiscible solvent; (b) adding a small amount of water to the solution to form a two-phase mixture; (c) refluxing the two-phase mixture for a period of time; and (d) removing the water. Optionally, an additional amount of the water-immiscible solvent may be added prior to removing the water. In this case, both the added amount of the water-immiscible solvent and the water are removed simultaneously. The treated metal organic acid salt solutions provide ceramic thin films having improved leakage characteristics as compared to the prior art thin films prepared from untreated prior art solutions.

Abstract: A mirror includes a mirror body with a reflective coating on at least one mirror surface. The mirror body is formed of a plastic into which a filler is mixed. The mirror body is preferably formed by injection molding of a mixture of the plastic and the solid filler. The mirror is used in optical imaging applications such as an infrared optical system.

Abstract: A solid state aperture is formed with an optical system and an electrode system. In different embodiments, the optical system includes electrically-responsive attenuation members, e.g., black guest host liquid crystals, and electrically-responsive, polarization-rotation members, e.g., twisted nematic liquid crystals. The electrode system includes electrodes of electrically conductive, optically transparent materials which are applied to the optical system to define attenuation segments of a desired attenuation pattern.

Abstract: A piezoelectric ceramic transformer made from a piezoelectric ceramic material stacked in a multilayer package which has a driving section 502 formed by alternately stacking piezoelectric ceramic layers polarized in a direction of thickness of the piezoelectric plate. The driving section 502 has internal interdigitated electrode layers 504A, 504B for causing piezoelectric vibration by a driving voltage applied to an input terminal (Vin). A first driven section 506, also made from piezoelectric ceramic layers polarized in the longitudinal direction of the piezoelectric plate, for generating a first output voltage (Vout1) at a first output by the piezoelectric vibration transmitted from the driving section 502. A second driven section 510, made from piezoelectric ceramic layers polarized in the thickness direction of the piezoelectric plate, for generating a second output voltage (Vout2) at a second output by the piezoelectric vibration transmitted from the driving section 502.

Abstract: Oxide materials having a composition described by the formula SrBi.sub.2.00- Ta.sub.2.00-x Nb.sub.x O.sub.9, where x ranges from 0.00 to 2.00 and is controlled to within about 1%, are provided having improved high temperature performance. A batch of the desired composition is initially prepared by conventional processes to provide a nominal composition that may be close to the desired composition, but not the exact desired composition. A portion of the batch is processed to form a thin film, the stoichiometry of which is then analyzed. The batch composition is then modified by adding thereto a quantity of one or more of the constituents to bring the batch composition to the desired stoichiometry. Further improved high temperature performance is achieved with values of x within the range of about 0.10 to 1.9, and more preferably, about 0.4 to 0.7, and most preferably about 0.56.