Abstract: Devices and methods are provided for assessing the condition of tissue, in particular to diagnose the location and stage of diseases such as emphysema. In one device or method according to the invention, sound is introduced into lung tissue. A portion of the sound is detected after it has passed through a portion of the lung. A sound-propagation parameter is determined by comparing a property of the introduced sound and a property of the detected sound. A region of examination of the tissue is identified, based in part on either a property of the component that introduces the sound or a property of the component that detects the sound. The condition of the tissue is assessed in the region of examination, based in part on the sound-propagation parameter.

Abstract: An AC electronic variable speed drive unit is used to power an AC induction motor that drives a centrifugal pump at controlled speeds for controlling the flow of a fluid process. The feedback loop controller function is implemented in the variable speed drive electronics, another network device, or may be located in a separate controller. This drive/motor/pump unit is used instead of a more conventional process control valve, with its attending actuator and positioning device, in order to improve the responsiveness, stability, and accuracy of the control loop. Coincidently, it also reduces the energy required for the process by the elimination of pressure drop across the control valve and allows a lower cost, smaller electric motor and pump to be used. Elimination of the control valve eliminates a source of fugitive emission through the valve packing, and reduces maintenance requirements that are necessary for a control valve.

Abstract: A method and a microprocessor controlled device for use in medical evaluation of the pulmonary system. The method and device incorporate two different non invasive evaluative techniques. Passive auscultation provides indicators of lung condition. Active auscultation, a different evaluative technique, provides information or indications generally not available or provided from passive auscultation. Combining the information from both techniques greatly improves the ability to provide effective medical treatment.

Abstract: A measurement device for generating an arterial volume-indicative signal includes an exciter and a detector. The exciter is adapted to receive an oscillating signal and generate a pressure wave based at least in part on the oscillating signal on the artery at a measurement site on a patient. The pressure wave includes a frequency. The detector is placed sufficiently near the measurement site to detect a volumetric signal indicative of arterial volume of the patient.

Abstract: A measurement device for generating an arterial volume-indicative signal includes an exciter and a detector. The exciter is adapted to receive an oscillating signal and generate a pressure wave based at least in part on the oscillating signal on the artery at a measurement site on a patient. The pressure wave includes a frequency. The detector is placed sufficiently near the measurement site to detect a volumetric signal indicative of arterial volume of the patient.

Abstract: A monitor for determining a patient's physiological parameter includes a calibration device that provides a calibration signal indicative of an accurate measurement of the patient's physiological parameter. The monitor also includes a processor, which receives a noninvasive signal from a noninvasive sensor positioned over a blood vessel. The processor uses the calibration signal to calibrate a relationship between the noninvasive signal and a property of the physiological parameter. The processor also determines when to recalibrate the relationship.