| Patent application number | Description | Published |
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| 20090073809 | METHOD AND APPARATUS FOR ACOUSTIC DATA TRANSMISSION IN A SUBTERRANEAN WELL - The disclosure describes a method and apparatus for effectively communicating data along an acoustic transmission path. The method comprises driving an acoustic transmitter to send a data signal along the acoustic transmission path, where the signal is distorted by ambient noise. The distorted signal is input to a spaced apart plurality of sensors so that consequent time-delayed signals provide reinforcement of the basic signal and attenuation of the ambient noise component when combined. | 03-19-2009 |
| 20100133004 | System and Method for Verifying Perforating Gun Status Prior to Perforating a Wellbore - A system for verifying perforating gun status prior to perforating a wellbore. The system includes a perforating gun ( | 06-03-2010 |
| 20100175867 | Well Tools Incorporating Valves Operable by Low Electrical Power Input - Well tools including valves operable by low electrical input. One well tool includes a valve which controls fluid communication between pressure regions in a well, the valve including a rotatable member which is biased to rotate, and a brake or clutch which prevents rotation of the member. Another valve includes a barrier which separates reactants, with the valve being operable in response to the barrier being opened and the reactants thereby reacting with each other. Yet another valve includes a barrier which separates the pressure regions, and a control circuit which heats the barrier to a weakened state. Another valve includes a member displaceable between open and closed positions, a restraining device which resists displacement of the member, and a control device which degrades or deactivates the restraining device and thereby permits the member to displace between its open and closed positions, in response to receipt of a predetermined signal. | 07-15-2010 |
| 20100177596 | Adaptive Carrier Modulation for Wellbore Acoustic Telemetry - Systems and methods of adaptive carrier modulation for acoustic telemetry. A method of transmitting an acoustic signal through a wellbore medium includes propagating the acoustic signal through the wellbore medium, the acoustic signal including symbols modulated on a carrier frequency, and the carrier frequency being changed during transmission of each of the symbols. A wellbore acoustic telemetry system includes a transmitter which propagates an acoustic signal through a wellbore medium in a manner such that the acoustic signal includes symbols modulated on a carrier frequency, with the carrier frequency being changed during transmission of each of the symbols. | 07-15-2010 |
| 20110199859 | METHOD AND APPARATUS FOR ACOUSTIC DATA TRANSMISSION IN A SUBTERRANEAN WELL - The disclosure describes a method and apparatus for effectively communicating data along an acoustic transmission path. The method comprises driving an acoustic transmitter to send a data signal along the acoustic transmission path, where the signal is distorted by ambient noise. The distorted signal is input to a spaced apart plurality of sensors so that consequent time-delayed signals provide reinforcement of the basic signal and attenuation of the ambient noise component when combined. | 08-18-2011 |
| Patent application number | Description | Published |
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| 20080275316 | SKIN IMPEDANCE MATCHING SYSTEM AND METHOD FOR SKIN/ELECTRODE INTERFACE - The present invention relates to a system for measuring the input impedance of a skin/electrode interface and selectively modifying the input impedance of the monitoring circuit to match the measured input impedance. More particularly, a simplified method for correcting for input impedance mismatch between electronic monitoring circuitry and the skin/electrode interface. In accordance with one embodiment of the invention, an input impedance measuring circuit will interface with a microprocessor and a reconfigurable switch network to select the input impedance of the electronic monitoring circuitry, thus eliminating the impedance sensitivity of EMG or EKG instruments. | 11-06-2008 |
| 20110190652 | SYSTEM AND METHOD FOR ACQUIRING AND DISPLAYING UTERINE EMG SIGNALS - A system and method for acquiring and processing uterine EMG signals from a maternal patient. Raw uterine EMG signals are acquired and processed in a central unit designed to isolate the patient and any internal circuitry from electrical shock. The central unit has a circuit board that amplifies and filters the EMG signal, then transmits the signal to an AID converter, after which the digitized signal is transmitted to a computer for further processing of the signal and subsequent display of a signal representative of uterine activity. The system and method provide a more accurate measurement of uterine EMG signals than a tocodynamometer or IUPC, and are useful in predicting delivery or monitoring the patient during post partum uterine activity. | 08-04-2011 |
| 20110237972 | NONINVASIVE MEASUREMENT OF UTERINE EMG PROPAGATION AND POWER SPECTRUM FREQUENCY TO PREDICT TRUE PRETERM LABOR AND DELIVERY - A method operable to more accurately predict true preterm labor and delivery is provided. Trans-abdominal uterine electromyography (EMG) and power spectrum (PS) analysis can identify electrical signals characteristic of labor at term and preterm with relatively high positive and negative predictive values. The use of propagation velocity (PV) of uterine EMG signals may either be done independently or in conjunction with PS analysis. This method involves applying at least two pairs of electrodes to a maternal abdomen. The time associated with measuring a voltage spike of a propagating myometrial wave traveling through the pairs of electrodes allows the amount of time required for the propagating myometrial wave to transverse the distance between electrodes to be determined. With this information a propagation velocity (PV) of the propagating myometrial wave may be determined. This PV may be compared to a labor positive predictive value (PPV). A favorable comparison indicates an increased probability of true preterm labor and delivery. | 09-29-2011 |
| 20110251512 | SYSTEM AND METHOD FOR ACQUIRING AND DISPLAYING ABDOMINAL EMG SIGNALS - A system and method for acquiring and processing abdominal EMG signals from a maternal patient to indicate when a maternal patient should push to progress the labor toward delivery. Raw abdominal EMG signals are acquired and processed in a central unit designed to isolate the patient and any internal circuitry from electrical shock. The central unit has a circuit board that amplifies and filters the EMG signal, then transmits the signal to an A/D converter, after which the digitized signal is transmitted to a computer for further processing and subsequent display of a signal representative of abdominal activity. The system may also acquire and process uterine EMG signals that can be evaluated in conjunction with the abdominal EMG signals. | 10-13-2011 |
| 20110251817 | METHOD AND APPARATUS TO DETERMINE IMPEDANCE VARIATIONS IN A SKIN/ELECTRODE INTERFACE - The present invention relates to a system for measuring the impedance of a skin/electrode interface and selectively modifying the system gain of the monitoring circuit to compensate for errors introduced by variations in the skin/electrode impedance. More particularly, a simplified, low-cost method for measuring and compensating for skin/electrode impedance variations is provided. The skin/electrode impedance measuring circuit and determines a system gain correction factor which may be applied to the measured signal using a software algorithm, thereby eliminating the need to change the circuit topology with a programmable gain amplifier or programmable resistor network. | 10-13-2011 |
