USA As Represented by Secretary of the Navy

Other

Richard A Katz

Albert H Nuttall

Derke R Hughes

Michael S Lawee

Jeffrey S Hall

Douglas Sawyer

Azizul H Quazi

Anthony Kiefer Newman

Tracey A Dodenhoff

John R Cooley

A Kief Newman

Richard A Grimm

Shalabh Chandra

Albert H Nuttal

James D Thomas

A method and apparatus is taught for a signal processing breakthrough that significantly alleviates the 'Curse of Dimensionality' (COD) in the characterization of nonlinear physical systems; namely, the reduction in the number of coefficients used to describe the higher order (i.e., nonlinear) kernels in the Volterra series expansion. The latter technique provides the means to evaluate simultaneously from a wide band excitation, all the inter-modulation products up to a specified order by greatly reducing the number of coefficients in the higher order kernel estimation to a manageable set that can be easily manipulated by current personal computers used to enhance a finite element (FE) model that generates a bio-inspired acoustic transducer model.

Bio-acoustic wave energy transducer

Provided herein are methods of using mannan oligosaccharides, to treat, palliate, relieve, prevent and/or eliminate urinary tract infections of humans. A mixture of oligosaccharides derived from yeast cell walls is shown to reduce, eliminate and prevent the symptoms of UTI in patients.

Method of palliating lower urinary tract infections by treatment with mannan oligosaccharides

The invention is a method for improved active sonar using a singular value decomposition filtering and a Volterra-Hermite Basis Expansion to model real active sonar measurements. The fitting model minimizes the sum of the squared errors between a measured channel response, z(t), and model response, y(t), which is a fitted Volterra Series solution. The model requires as input an excitation waveform, x(t), to which is fitted the model response, y(t). A contracted broadband cross-ambiguity function is used to correct the excitation waveform for Doppler and range effects. Once completed, the modeled response can be used to determine the linearity or non-linearity of the channel effects. Appropriate measures can be utilized to reduce these effects on the measured channel response.

Method and apparatus for improved active sonar using singular value decomposition filtering

A fault detection system designed to evaluate the structural integrity of a material employs an array of sensors disposed over the material being evaluated. The sensors detect vibrations in the material and the sensor signals are fed to a data processor. The processor employs a method to analyze the linear and nonlinear characteristics of the sensor signals and then determines whether to proceed with a linear signal processing analysis or a nonlinear signal processing analysis of the sensor signals. Once the analysis is completed, the results are compared to baseline results to determine what if any divergence exists between the results and the baseline results. A significant divergence indicates a potential material failure. The fault detection system will indicate such a potential failure through a visual alarm on a graphical user interface.

Signal processing fault detection system

A method is provided for identifying a disease of a patient. The method includes collecting data of at least one cardio-respiratory function of the patient over time, eliminating artifacts from the collected data to create a new data record, constructing a phase-space from the new data record, and constructing a hypercube covering the phase-space. The method further includes calculating threshold criteria for quantifying dispersion characteristics of an attractor of the phase-space and determining the patient's tendency towards the disease based on the threshold criteria.

Apparatus and method for identifying sleep apnea

A sonar system and method are provided to extract and identify information about a particular target illuminated by an active sonar system. The present invention utilizes a Volterra Series Expansion in conjunction with a least squares procedure to estimate channel and target responses, which may be linear or nonlinear. The system estimates the channel and target responses for different orders of the Volterra Series Expansion and then selects the order for which a minimum error is determined with respect to a measured acoustic return signal. The system requires as inputs only the excitation waveform and the measured acoustic return signal.

System and method for active sonar signal detection and classification

The present invention provides a method and apparatus for enhancing active sonar signal detection by estimating the channel/target response utilizing measured values of the excitation signals and received signals. A Wiener/Volterra series expansion for the excitation and received signals is used as a model, wherein a time invariant environment is assumed, thereby disregarding all random noise contributions. The Wiener/Volterra kernels are then determined in a nonlinear processor using a method of correlations which is designed to produce the kernels utilizing only measured white Gaussian excitation signals and received signals. The kernels can be used to give an optimum correlation between the excitation signals and the received signals.

Method and apparatus for active sonar detection enhancement

An apparatus and method for identifying the timing of the onset of and duration of an event characteristic of sleep breathing disorder while a patient is awake. Chaotic processing techniques analyze data concerning a cardio-respiratory function, such as nasal air flow. Excursions of the resulting signal beyond a threshold provide markers for delivering the average repetition rate for such events that is useful in the diagnosis of obstructed sleep apnea and other respiratory dysfunctions.

Method and apparatus for diagnosing sleep breathing disorders while a patient in awake

A nonlinear signal processing system and method is used to identify nonlinearity (e.g., chaos) in underwater acoustic signals, such as sonar signals. The system and method detects the underwater acoustic signal and digitizes the underwater acoustic signal to produce an acoustic time series. The acoustic time series is reconstructed using a phase space embedding algorithm to generate a phase space embedded acoustic signal. A differential radius signal is generated from the phase space embedded acoustic signal using chaotic radius computations and differential radius computations. Thresholds can be detected in the differential radius signal to reveal nonlinear or chaotic events hidden in the underwater acoustic signal.

System and method for processing an underwater acoustic signal by identifying nonlinearity in the underwater acoustic signal

A system is disclosed that applies non-linear signal processing methods derived from theories of information and non-linear oscillations (chaos) to control the turbulent boundary layer of marine vessels in order to reduce the drag to which the vessels encountered while moving in water. The system uses measurement probes mounted along the hull of a marine vessel to provide detection markers for increase or decrease in the drag based on a prescribed fluid (i.e., air) injection and flow rate in boundary layer. The invention utilizes a differential radius (DR) to determine the minimum entropy for a given flow rate in the boundary layer which defines the optimum condition used by the system for reducing drag.

Method and apparatus for reducing drag in marine vessels

An apparatus and method for identifying the timing of the onset of and duion of an event characteristic of sleep breathing disorder. Chaotic processing techniques analyze data concerning one or more cardio-respiratory functions such as nasal air flow, chest wall effort, oxygen saturation, heart rate and heart activity. Excursions of the resulting signal beyond a threshold provide markers for the timing of such an event that is useful in the diagnosis of obstructed sleep apnea and other respiratory dysfunctions.

Method and apparatus for diagnosing sleep breathing disorders

An apparatus and method for predicting the efficacy of cardioversion as a dality for reverting a patient with atrial fibrillation to normal sinus rhythm. Blood flow through the patient's atrium is measured, converted and processed using nonlinear or chaotic processing to obtain a differential radius signal. The number of excursions of the differential radius beyond a threshold value indicates whether cardioversion will be successful.

Method and apparatus for predicting the efficacy of cardioversion

A method of detecting the onset of turbulence in connection with a body mng through a fluid medium and of reducing body drag and as well reducing the amount of drag noise radiated from the body. First, the body is supplied with sensors each for generating a signal suitable for measuring amplitude of pressure fluctuations of the medium proximate a region of said sidewall of the body in at least a region of the body in which turbulence is expected to occur. During a reference stage during which the body moves through the fluid medium when it is known that turbulence is occurring around at least a portion of said body, the sensors each generate reference temporal pressure data representing fluctuations in pressure of the fluid medium around said body. In response to reference temporal pressure data generated by sensors in a turbulence zone at which turbulence is occurring and sensors in a transition zone between the turbulence zone and a laminar flow zone, method-of-delay phase portraits are generated for a progression of selected delay intervals. During an operational stage, the signals from the sensors are filtered to generate a portion representing the turbulence due to motion of the body through the medium and a portion representing signals from external acoustic signal sources, and the turbulence signal portion is used to generate signals of appropriate phase which are injected into the medium to reduce the turbulence noise signals and thereby reduce drag on the body due to the medium.

Method and system for reducing drag on a body moving through a fluid

A method of detecting the onset of turbulence in connection with a body mng through a fluid medium and reducing turbulence noise in acoustic sensor systems carried thereby. First, the body is supplied with sensors each for generating a signal suitable for measuring amplitude of pressure fluctuations of the medium proximate a region of said sidewall of the body in at least a region of the body in which turbulence is expected to occur. During a reference stage during which the body moves through the fluid medium when it is known that turbulence is occurring around at least a portion of said body, the sensors each generate reference temporal pressure data representing fluctuations in pressure of the fluid medium around said body. In response to reference temporal pressure data generated by sensors in a turbulence zone at which turbulence is occurring and sensors in a transition zone between the turbulence zone and a laminar flow zone, method-of-delay phase portraits are generated for a progression of selected delay intervals. During an operational stage, the signals from the sensors are filtered to generate a portion representing the turbulence due to motion of the body through the medium and a portion representing signals from external acoustic signal sources, and the turbulence signal portion is used to generate signals of appropriate phase which are injected into the medium to reduce the turbulence noise signals.

Method and system for suppressing noise induced in a fluid medium by a

A method of detect the onset of turbulence in connection with a body moving hrough a fluid medium. First, the body is supplied with sensors each for generating a signal suitable for measuring amplitude of pressure fluctuations of the medium proximate a region of said sidewall of the body in at least a region of the body in which turbulence is expected to occur. During a reference stage during which the body moves through the fluid medium when it is known that turbulence is occurring around at least a portion of said body , the sensors each generate reference temporal pressure data representing fluctuations in pressure of the fluid medium around said body. In response to reference temporal pressure data generated by sensors in a turbulence zone at which turbulence is occurring and sensors in a transition zone between the turbulence zone and a laminar flow zone, a method-of-delay phase portrait is generated for each of a progression of selected delay intervals. These operations are repeated during an operational stage, and phase portraits generated during the operational stage are compared to phase portraits in response to the reference temporal pressure data from the transitional zone and the turbulence zone, for corresponding ones of said selected delay intervals,, and a determination of the onset of turbulence is made in response to such comparison.

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East Lyme, CT, United States of America

Richard A Katz