Patents by Inventor Dexter G. Smith
Dexter G. Smith has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 7283868Abstract: An electromagnetic bioimpedance measurement apparatus uses an alternating magnetic field to induce electrical eddy currents in biological tissue. The eddy currents produce secondary magnetic fields that have the effect of changing the mutual inductance between the tissue and the coil that applied to the initial magnetic field. The amplitude of the resultant voltage, as measured by the same coil or a different receiver coil, is proportional to the conductivity of the tissue. A simple, marginally stable oscillator circuit is used to generate the current into the coil. Nearfield holographic signal processing is then used for holographic image formation. Bioimpedance is used to distinguish between normal tissue and cancerous tissue, especially cancerous prostate tissue. An invasive embodiment includes driven needle electrodes that are inserted into the body segment to be tested. Noninvasive embodiments include single or multiple coils arranged on a probe shaft.Type: GrantFiled: April 5, 2001Date of Patent: October 16, 2007Assignee: The Johns Hopkins UniversityInventors: Harvey W. Ko, Dexter G. Smith
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Patent number: 7032589Abstract: A portable ventilator for providing an air-recipient with compulsory respiration is provided with an outlet manifold and a single-expansion-chamber muffler configured so that airflow through an inhale outlet port of the muffler is pulse-free and a transmission loss, defined as the ratio of sound power generated by the at least one compressor and incident on the muffler to the sound power transmitted by the muffler, is sufficient to deaden the sound power of the compressor.Type: GrantFiled: January 23, 2003Date of Patent: April 25, 2006Assignee: The Johns Hopkins UniversityInventors: Charles W. Kerechanin, II, Dexter G. Smith, Jennifer A. Nix, Protagoras N. Cutchis
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Patent number: 6853194Abstract: A time-domain electromagnetic target discriminator (ETD) sensor system and method are provided capable of measuring a metal target's time decay response based on the physical parameters of the metal target and its environment and for identifying the metal target. The ETD sensor system includes a pulse transmitter connected to a receiver via a data acquisition and control system. The transmitter and receiver include coil configurations for placement in proximity to a visually obscured, e.g., buried, metal target (or underground void) for inducing eddy currents within the metal target. The ETD sensor system measures the eddy current time decay response of the metal target in order to perform target recognition and classification. The identification process entails comparing the metal target's (or, underground void or other object's) time decay response with a library of normalized object signatures, e.g., time decay responses and other characteristics.Type: GrantFiled: March 20, 2001Date of Patent: February 8, 2005Assignee: The Johns Hopkins UniversityInventors: Carl V. Nelson, Dexter G. Smith
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Patent number: 6848444Abstract: An emergency life support system including a patient ventilator for mechanical breathing assistance; a capnograph to monitor CO2 for ventilation effectiveness; a pulse oximeter for measuring blood stream oxygen saturation; a carbon dioxide sensor; an electrocardiograph (ECG) to monitor cardiac performance; an infusion pump; and alarms and a data recorder. The preferred embodiment uses an oxygen generator to deliver oxygen, to generate electric power to run the ventilation system, and to warm IV fluids and resuscitated air. The generator has electronically controlled valves and a modified valve system that offers the ability to select the oxygen concentration in the air delivered to the patient.Type: GrantFiled: July 31, 2001Date of Patent: February 1, 2005Assignee: The Johns Hopkins UniversityInventors: Dexter G. Smith, Protagoras N. Cutchis, William P. Wiesmann, Loland A. Pranger
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Publication number: 20040252585Abstract: A high capacity digital geophone system capable of distributing seismic data over a computer network connection in a real-time manner. Each geophone can convert seismic energy signals to analog then digital data before forwarding the observed data to a network connection for dissemination. Moreover, each geophone may be embedded with a processing capability that allows for instant front end processing of data. Remote processing computers can then access geophone data over the network connection and feed it into software analysis applications.Type: ApplicationFiled: April 14, 2004Publication date: December 16, 2004Inventors: Dexter G. Smith, Nicholas H. Evancich, Michael P. McLoughlin, Douglas S. Wenstrand
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Patent number: 6765527Abstract: A harmonic radar nonlinear junction detector system for detecting concealed weapons, electronics, and other man-made objects utilizing state-of-the art wireless technology, circuit fabrication, signal synthesis, and computer processing techniques to detect and characterize man-made objects possessing nonlinear junctions. The system transmits a pair of low power waveforms and a receiver within the system is coherently tuned to harmonics of the transmitted frequencies of the waveforms to detect man-made metal objects and electronics that contain non-linear junctions. The receiver is also capable of receiving inter-modulation products reflected from the man-made objects that are a result of using two incident signals. The system uses two signal sources generating user-definable waveforms of variable frequencies in order to provide enhanced discrimination and target identification abilities via the processing of returned inter-modulation products.Type: GrantFiled: January 31, 2002Date of Patent: July 20, 2004Assignee: The Johns Hopkins UniversityInventors: Daniel G. Jablonski, Harvey W. Ko, Douglas A. Oursler, Dexter G. Smith, David M. White
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Patent number: 6647983Abstract: A low-pressure valve enabling precise control of a fluid flow rate through the valve during cyclical operation of the valve. The valve is useful for controlling air delivery to a patient as part of a portable ventilator. The valve comprises a housing having an inlet 16 and two outlets 18 and 20. A wiper plate 22 and an orifice plate 24 are disposed inside of the housing. Transverse movement of the wiper plate 22 relative to the orifice plate 24, powered for example by a servomotor 34, simultaneously and alternatively covers and uncovers various openings 26 in the orifice plate 24. The total flow through the valve is thereby divided between the two outlets 78 and 20.Type: GrantFiled: March 6, 2001Date of Patent: November 18, 2003Assignee: The Johns Hopkins UniversityInventors: Dexter G. Smith, Michael P. Boyle, Protagoras N. Cutchis, William R. Allmon
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Publication number: 20030179126Abstract: A harmonic radar nonlinear junction detector system for detecting concealed weapons, electronics, and other man-made objects utilizing state-of-the art wireless technology, circuit fabrication, signal synthesis, and computer processing techniques to detect and characterize man-made objects possessing nonlinear junctions. The system transmits a pair of low power waveforms and a receiver within the system is coherently tuned to harmonics of the transmitted frequencies of the waveforms to detect man-made metal objects and electronics that contain non-linear junctions. The receiver is also capable of receiving inter-modulation products reflected from the man-made objects that are a result of using two incident signals. The system uses two signal sources generating user-definable waveforms of variable frequencies in order to provide enhanced discrimination and target identification abilities via the processing of returned inter-modulation products.Type: ApplicationFiled: January 31, 2002Publication date: September 25, 2003Inventors: Daniel G. Jablonski, Harvey W Ko, Douglas A Oursler, Dexter G Smith, David M White
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Publication number: 20030172931Abstract: A portable ventilator for providing an air-recipient with compulsory respiration is provided with an outlet manifold and a single-expansion-chamber muffler configured so that airflow through an inhale outlet port of the muffler is pulse-free and a transmission loss, defined as the ratio of sound power generated by the at least one compressor and incident on the muffler to the sound power transmitted by the muffler, is sufficient to deaden the sound power of the compressor.Type: ApplicationFiled: January 23, 2003Publication date: September 18, 2003Inventors: Charles W. Kerechanin, Dexter G. Smith, Jennifer A. Nix, Protagoras N. Cutchis
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Publication number: 20030052684Abstract: A time-domain electromagnetic target discriminator (ETD) sensor system and method are provided capable of measuring a metal target's time decay response based on the physical parameters of the metal target and its environment and for identifying the metal target. The ETD sensor system includes a pulse transmitter connected to a receiver via a data acquisition and control system. The transmitter and receiver include coil configurations for placement in proximity to a visually obscured, e.g., buried, metal target (or underground void) for inducing eddy currents within the metal target. The ETD sensor system measures the eddy current time decay response of the metal target in order to perform target recognition and classification. The identification process entails comparing the metal target's (or, underground void or other object's) time decay response with a library of normalized object signatures, e.g., time decay responses and other characteristics.Type: ApplicationFiled: July 17, 2002Publication date: March 20, 2003Inventors: Carl V Nelson, Dexter G Smith, Charles B Cooperman
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Publication number: 20030055358Abstract: An electromagnetic bioimpedance measurement apparatus uses an alternating magnetic field to induce electrical eddy currents in biological tissue. The eddy currents produce secondary magnetic fields that have the effect of changing the mutual inductance between the tissue and the coil that applied to the initial magnetic field. The amplitude of the resultant voltage, as measured by the same coil or a different receiver coil, is proportional to the conductivity of the tissue. A simple, marginally stable oscillator circuit is used to generate the current into the coil. Nearfield holographic signal processing is then used for holographic image formation. Bioimpedance is used to distinguish between normal tissue and cancerous tissue, especially cancerous prostate tissue. An invasive embodiment includes driven needle electrodes that are inserted into the body segment to be tested. Noninvasive embodiments include single or multiple coils arranged on a probe shaft.Type: ApplicationFiled: August 22, 2002Publication date: March 20, 2003Inventors: Harvey W. Ko, Dexter G Smith
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Publication number: 20030029453Abstract: An emergency life support system including a patient ventilator for mechanical breathing assistance; a capnograph to monitor CO2 for ventilation effectiveness; a pulse oximeter for measuring blood stream oxygen saturation; a carbon dioxide sensor; an electrocardiograph (ECG) to monitor cardiac performance; an infusion pump; and alarms and a data recorder. The preferred embodiment uses an oxygen generator to deliver oxygen, to generate electric power to run the ventilation system, and to warm IV fluids and resuscitated air. The generator has electronically controlled valves and a modified valve system that offers the ability to select the oxygen concentration in the air delivered to the patient.Type: ApplicationFiled: July 31, 2001Publication date: February 13, 2003Inventors: Dexter G. Smith, Protagoras N. Cutchis, William P. Wiesmann, Loland A. Pranger
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Publication number: 20030006899Abstract: Disclosed is a method for detecting unwanted dissemination of acrosolized agents into an HVAC system in a building by detecting the sound of the dissemination at the time it occurs. To be able to distinguish the sound of the dissemination event from the ambient background noise of the HVAC system, sound extraction techniques, e.g., high pass filtering and an adaptive variance estimator, are utilized which can detect the event's noise from within the ambient background noise of the system. A microphone continually monitors background sound levels and senses the additional sound resulting from the activation of the aerosol delivery system, which has a unique sound “signature”. Once an event is detected, defensive actions, e.g., activating additional sensors, closing all air vents, and shutting off the HVAC system, can be taken.Type: ApplicationFiled: January 15, 2002Publication date: January 9, 2003Inventors: Amir-Homayoon Najmi, Dexter G. Smith, Michael P. McLoughlin, Harvey W. Ko
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Publication number: 20010035187Abstract: A low-pressure valve enabling precise control of a fluid flow rate through the valve during cyclical operation of the valve. The valve is useful for controlling air delivery to a patient as part of a portable ventilator. The valve comprises a housing having an inlet 16 and two outlets 18 and 20. A wiper plate 22 and an orifice plate 24 are disposed inside of the housing. Transverse movement of the wiper plate 22 relative to the orifice plate 24, powered for example by a servomotor 34, simultaneously and alternatively covers and uncovers various openings 26 in the orifice plate 24. The total flow through the valve is thereby divided between the two outlets 78 and 20.Type: ApplicationFiled: March 6, 2001Publication date: November 1, 2001Inventors: Dexter G. Smith, Michael P. Boyle, Protagoras N. Cutchis, William R. Allmon
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Patent number: 5692054Abstract: A repetitive noise cancellation system for multiple noise sources employing a controller (36) which senses radiated noise by reference sensors (35) and the status of the noise sources by position sensors (37, 38) and automatically controls one of the noise sources so that the noises being emitted from the multiple sources cancel one another.Type: GrantFiled: June 30, 1995Date of Patent: November 25, 1997Assignee: Noise Cancellation Technologies, Inc.Inventors: Michael J. Parrella, Dexter G. Smith
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Patent number: 5502869Abstract: An ultra quiet vacuum cleaner having a bag cavity (44), a motor/blower chamber (48) connected to said cavity by a flexible coupling (47) and an active, adaptive noise cancellation controller (52) so configured to quiet the exhaust of the air used to cool the motor/blower unit. Fast compensation and feedback compensation allow use of a straight, short duct (51) for superior cancellation performance.Type: GrantFiled: October 27, 1994Date of Patent: April 2, 1996Assignee: Noise Cancellation Technologies, Inc.Inventors: Dexter G. Smith, Christopher P. Nowicki, Michael F. Arnold