Abstract: A cruise missile, such as the Tomahawk cruise missile, is adapted to deploy decoys in an area as the missile progresses along its preprogrammed course. Each decoy is shaped to be compatible with and ejected from the Tomahawk and has a preprogrammed control unit operating a transmitter connected to an extendible antenna. False beacon signals and/or false message signals are transmitted from each of the decoys to deceive and confuse defensive forces, such as enemy searchers looking for a downed airman.

Abstract: An inflatable sealing device is used to seal a door, such as a shutter door in a submarine, when the door is closed. The inflatable sealing device includes a seal retainer positioned around the opening through a structure, such as a submarine hull or other type of wall. An inflatable seal is positioned with a retainer cavity within the seal retainer. The inflatable seal includes a seal periphery and a seal tip extending from the seal periphery. The seal periphery preferably has an elliptical cross section in a deflated state and a circular cross section in an inflated state such that the seal tip extends into a gap to seal the door when the inflatable seal is pressurized and inflated. The seal tip retracts into the seal retainer when the inflatable seal is deflated. A pressure actuator, such as a bellows, is used to pressurize the inflatable seal using an actuating fluid.

Abstract: An electrical connector includes a plug section having a body, and a receptacle section which is connected to the plug section. A collapsible seal is disposed within a circumferential groove formed in the plug section. The receptacle section has a cylindrical housing with a clamping ring for securely engaging and connecting the receptacle section to the plug section. Upon connecting the receptacle section to the plug section any hydrostatic forces present in the chamber between the receptacle section and the plug section causes the collapsible seal to collapse within the groove thereby providing a volume defined by the groove which receives fluid therein for preventing hydrostatic lock.

Abstract: A digital goniometer and steering method are provided which may be used, in a preferred embodiment, for producing a figure-eight antenna reception pattern oriented at any selectable angle. The digital goniometer works with the signals from a pair of orthogonal antenna loops. In a presently preferred embodiment a first register and a second register are provided for a respective first variable gain amplifier and a second variable gain amplifier. The first and second registers receive from software a digital value related to a sine function and cosine function of the selectable angle. The first and second registers are utilized to set the gain of the first and second variable gain amplifiers. The outputs of the first and second variable gain amplifiers are added to produce the reception signal.

Abstract: An apparatus for measuring velocity of a projectile includes a plurality of break-screens aligned with each other serially and along a line of travel of the projectile, and parallel to each other, and spaced from each other and from a projectile firing device by selected distances. Each break-screen includes a support sheet and an electrically conductive wire mounted on the sheet so as to be interrupted by passage of the projectile through the sheet. A single amplifier is in communication with each of the conductive wires and is adapted to provide an indication as to a change in voltage in each of the break-screens upon passage of the projectile therethrough, and an indication as to time of the passage. A data collection/display apparatus computes therefrom the velocity of the projectile.

Abstract: A pressure balanced floating seal system positioned within a structure about a rotating shaft. The floating seal system has a cylindrical outer seal housing having a cylindrical internal recessed region formed in the outer seal housing with a retaining flange extending into said internal recessed region. A cylindrical inner seal housing is positioned within the internal recessed region. The inner seal housing has an annular internal surface for accommodating the rotating shaft. Two sealing member retaining grooves are formed in the inner seal housing annular internal surface and a lubricant recess is formed between the two grooves. An intermediate seal is retained on the forward side of the inner seal housing forward face between the inner seal housing and the outer seal housing at the retaining flange. Sealing members are positioned in the sealing member retaining grooves at substantially the same radius as the intermediate seal.

Abstract: A method and apparatus are provided for automatically characterizing the spatial arrangement among the data points of a three-dimensional time series distribution in a data processing system wherein the classification of said time series distribution is required. The method and apparatus utilize grids in Cartesian coordinates to determine (1) the number of cubes in the grids containing at least one input data point of the time series distribution; (2) the expected number of cubes which would contain at least one data point in a random distribution in said grids; and (3) an upper and lower probability of false alarm above and below said expected value utilizing a discrete binomial probability relationship in order to analyze the randomness characteristic of the input time series distribution.

Abstract: An antenna apparatus (and corresponding innate method) comprises an array of antenna elements each having a phase center. An “observable signal” that contains a low-frequency component and a high-frequency component is generated. The high-frequency component is summed with the signal received by each antenna element near its phase center, forming a plurality of sum signals. These are fed into a signal processing arrangement that processes these signals with the low frequency component of the observable signal, including analog to digital conversion to (i) remove the high frequency component of the observable signal, (ii) normalize the effects of the signal transfer characteristics on the digital sum signals, (iii) synchronously re-sample the digital sum signals, and (iv) differentially time-reference each digital sum signal to the phase center of the corresponding antenna element. The thusly, processed digital signals are combined into a single composite signal.

Abstract: A system is disclosed that provides. a sonar operator with the most likely range to a target of interest. The system generates and displays a contour based on ship's parameters, target parameters, environmental data, and operator parameters. The sonar operator can vary many of the parameters in “what if” scenarios so as to generate groups of contours for preselected probabilities of detection. Contours can be used to show the actions that should be taken to ensure a favorable outcome.

Abstract: The present invention relates to an improved magnesium semi-fuel cell which has a magnesium anode, a seawater/catholyte electrolyte, preferably containing acid to solubilize solid precipitates, and an electrocatalyst composed of palladium and iridium catalyzed onto carbon paper. The acid added to the electrolyte is preferably selected from the group consisting of sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, and mixtures thereof.

Abstract: The present invention relates to a windmill power generation system which includes at least two variable camber blades fastened to a rotatable hub, which blades are driven by a fluid such as wind. Each of the variable camber blades has embedded shape memory alloy members. The system also includes a source of electrical power connected to the shape memory alloy members for varying the shape of the blades in response to changes in the speed of the fluid driving the blades. The power generating system further includes a power regulator connected to the electrical power source for regulating the electrical power being supplied to the shape memory alloy members and a controller for transmitting a power command signal to the power regulator. The controller preferably comprises a preprogrammed computer having an algorithm for generating the optimum blade shape for a particular wind speed or condition.

Abstract: A system for sensing water temperature includes a tow cable with an exterior surface having at least one helical groove formed therein and a metal tube lying in each helical groove. At least one optical temperature sensing element is provided in each metal tube. A thermally-conducting material fills each metal tube and surrounds each optical temperature sensing element contained therein. An outer jacket layer is formed over the tow cable and metal tube.

Abstract: A system and method is disclosed for generating, propagating, and detecting light pulses for use with a fiber optic transducer array. The system preferably uses two pulses to provide fixed and relatively short interferometer path differences to thereby reduce coherent light noise. The system preferably uses a surface acoustic wave device for chirping the light pulses to thereby spread noise over a wider bandwidth so as to suppress noise. A coherent light source is preferably amplitude modulated to produce an initial pulse. In one embodiment, that initial pulse is chirped and split into two pulses. One of the two pulses is delayed while the other is frequency shifted. The two pulses are combined onto a single fiber optic path and applied to the fiber optic transducer array. After being acted on by the fiber optic transducer array, the two pulses are photodetected and processed to obtain the information about the physical phenomena to be detected.

Abstract: The present invention relates to a tether retraction device having particular utility with multi-line towed arrays. A system for retrieving and deploying a multi-line towed array having a plurality of array lines has at least one tether joinable between two of the plurality of array lines. A tether retraction device is incorporated into at least one of the array lines for retracting the tether. Each tether retraction device has a tether take-up spool, and a spring driven drive means which causes the tether to wind onto the take-up spool when the array is towed at slow speeds and allows deployment of the tether from the take-up spool when tension in the tether caused by tow forces exceeds the spring force applied by the spring driven drive means.

Abstract: A system and method for training a class-specific hidden Markov model (HMM) is used for modeling physical phenomena, such as speech, characterized by a finite number of states. The method receives training data and estimates parameters of the class-specific HMM from the training data using a modified Baum-Welch algorithm, which uses likelihood ratios with respect to a common state (e.g., noise) and based on sufficient statistics for each state. The parameters are stored for use in processing signals representing the physical phenomena, for example, in speech processing applications. The modified Baum-Welch algorithm is an iterative algorithm including class-specific forward and backward procedures and HMM reestimation formulas.

Abstract: The present invention provides a method utilizing a wavelet transform for improving and optimizing the visual display of image data at the time of viewing to provide enhanced information analysis capability for image analysis such as breast cancer screening and diagnosis. Through the use of an interactive software tool, the user displays both unprocessed and processed images simultaneously. The method also allows additional enhancement iterations resulting in better image reading and interpretation. In the case of digital mammography images, this technique allows suppression of background details and enhancement of selected features allowing additional diagnostic capability.

Abstract: A three-dimensional imaging system for use with a sonar system. The three-dimensional imaging system processes forward-looking sonar data, side-looking sonar data, bathymetric data, detection and cluster data, bottom sediment type data, and vehicle position and navigation data and renders a complete three-dimensional image of an ensonified region.

Abstract: A method is provided that increases fracture toughness and reduces brittleness of a semi-crystalline ferroelectric polymer material while substantially maintaining ferroelectric properties of the material. The material is heated in an inert oxygen-free atmosphere to a temperature above the material's Curie transition but below its melting temperature. The material is then irradiated with beta particles to provide a desired level of fracture toughness that substantially maintains ferroelectric properties of the material. In the case of poly(vinylidene fluoride-trifluorethylene), the heating temperature is just above the material's Curie transition temperature, the beta particles have an energy level of approximately 2.5 mega electron volts (MeV), and the radiation dose should not exceed approximately 50 megarads (Mrads).

Abstract: A radially pressure balanced floating seal system is used to seal a rotating shaft, such as a drive shaft in a torpedo, or other type of vehicle or machinery. The radially pressure balanced floating seal includes an outer seal housing and an inner seal housing that floats with respect to the outer seal housing. The outer seal housing is secured proximate the shaft bearings, for example, in the tail cone of a torpedo. The inner seal housing is secured within an internal recessed region in the outer seal housing, and two or more discrete torque members or one distributed torque member extend from the outer seal housing to the inner seal housing to prevent rotation of the inner seal housing while allowing movement generally in a radial direction. The inner seal housing includes a lubricant recess formed within an internal annular aperture of the inner seal housing for containing lubricant. Double canted O-rings are disposed on each side of the lubricant recess in double canted O-ring grooves.

Abstract: A system and method is disclosed for a radar receiver, such as a wideband crystal video early warning receiver, to automatically detect the noise level of the radar receiver with immunity to high pulse repetition frequencies and high duty cycle signals. The noise riding threshold circuit utilizes high frequency components of the noise and, to the attenuated extent present, high frequency components of the video signal to produce the noise riding threshold voltage. An amplifier gain control permits adjusting the noise-riding threshold to a fixed relative level. In a preferred embodiment, the noise riding threshold control of the present invention utilizes current feedback amplifiers for wide bandwidth, high gain video amplifiers.