Abstract: A method and apparatus for efficiently coupling a transceiver to an AC power line transmission system. The preferred embodiment of the coupling system comprises a line coupling network and first and second filter ports. The first filter port is connected to a resonant circuit having bandpass filtering characteristics adapted to the specific needs of the transmitter portion of the transceiver. The second filter port is isolated from the low impedance of the AC power line and is connected to a high quality factor filter having bandpath filtering characteristics adapted to the specific needs of the receiver portion of the transceiver.

Abstract: An improved system for use in drilling a relief well to intersect a target blowout well. A probable location distribution is used to survey the location of the candidate relief wells and the blowout well. Through the use of the relative probable location distribution, the integral probabilities of find, intercept and collision are calculated. A relief well plan is then optimally designed to drill and insure a high integral probability of a find and intercept and a low probability of a collision. The method provided by the present invention allows a relief well to be drilled in a minimum time with minimum risk exposure.

Abstract: A novel and improved automatic gain control (AGC) circuit which is ideally suited for use with sound systems which are operated in a very large environment, such as a supermarket or auditorium. The preferred embodiment of the circuit comprises first and second input channels and a single output channel. The first input channel is a feedback signal provided by a microphone which is placed near one of the speakers of the sound system. The second input channel receives a music signal which is being played by the sound system. The output of the circuit is a music signal which has a constant ratio relative to the noise detected in the environment. Constant power ratio operation of the system is achieved through the use of logarithmic processing of the signals in each of the respective input channels. Control circuitry is provided to maintain the gain level of the system at a constant level during periods of time when no music is present on the second input channel.

Abstract: A analytic bone implant includes a cylindrical housing with an inner chamber designed for collecting sample of bone tissues. The outer surface of the housing is provided with a plurality of threads for securing the implant into bone tissue. The housing is further provided with a plurality of openings to allow new bone tissue to grow into a collecting basket. The openings in the housing are alignable with complementary openings in the basket. The openings on the basket are provided with sharp edges which serve as cutting blades to facilitate the removal of the bone sample. The implant includes provision for repeated access to the medullary compartment for obtaining sample of cancellous tissue for histologic and morphometric analysis.

Abstract: An improved fluid transformer which is capable of controlling the position of the operating pistons within the apparatus so that pressure equilibrium is maintained and the movements of the pistons are limited to predetermined locations within the cylinders. The transformer is capable of operating in a contaminated environment by purging unwanted fluid contamination from the internal workings of the transformer. Dynamic piston and cylinder seals are positioned such that destructive pressure forces are counteracted by opposite frictional forces during operation, thereby allowing the seals to remain effective at high pressures for long periods of time.

Abstract: The communications system of the present invention defines a complete feedback path consisting of first and second transceivers and an appropriate signal path. Each transceiver comprises a detector and a signal source capable of generating a signal at one of two frequencies. The detector in each of the transceivers is a two state device tuned to respond only to a predetermined desired difference frequency. If the desired difference frequency signal is present, the detector provides and output signal in a first state; if the desired difference signal is not present, the detector provides an output signal which is in a second state. The signal source can be a voltage controlled oscillator, a pair of single frequency oscillators, a synthesizer, or any signal source capable of being electrically switched between two frequencies. Data can be exchanged between the transceiver pair only when the desired difference frequency is present.

Abstract: An improved biological signal detector which is extremely sensitive, yet resistant to the effects of high frequency noise. A multiplexed signal representation of a plurality biological signals is demultiplexed by a detector circuit comprising a plurality of switches each of which controls an individual storage network. A switch logic control circuit synchronizes the various switches to close during the time intervals corresponding to the pulse amplitudes representing the particular signal of interest. The amplitude of the alternating component of each of the biological signals is stored in one of the respective storage networks over a number of pulse time intervals. In the preferred embodiment, the storage networks of the detector each have a time constant which is purposely chosen to be substantially longer than the time interval of the pulses.

Abstract: A method for monitoring a transducer array of individual pressure or force sensitive elements and for selecting the element within the array which most tracks the actual pulse waveform in an underlying artery, thus providing the most accurate measurement of the patient's blood pressure. The outputs of all of the transducer elements are employed in locating the particular element which is centrally located over the artery. A limited number of elements exhibiting local minima of diastolic pressure is first chosen. Then, pulse amplitude outputs from the limited number of transducer elements are employed in selecting that element within the limited-number group which is to be used for obtaining blood pressure measurements. The method provided by the present invention selects from the limited-number group of elements that element about which is centered the greatest spatially weighted average of a predetermined number of pulse amplitude values.

Abstract: An improved optical sensor which has increased sensitivity and which is resistant to the effects of ambient light. In one embodiment of the invention, the sensor housing has a flat lower face with a central protrusion in which a plurality of light emitting diodes and an optical sensor are mounted. When the sensor is placed on the patient's tissue, the portion of the sensor face containing the LEDs and detector protrudes slightly into the tissue to provide improved optical coupling of the sensor to the skin. A light absorbing compliant material is attached to the perimeter of the sensor to reduce the effects of ambient light and to provide a cushion to minimize discomfort to the patient. In an alternate embodiment of the sensor, the LEDs and detector are mounted in a horizontal configuration substantially parallel to the surface of the tissue. The light produced by the LEDs is projected into a central chamber of the housing where the respective beams are combined and directed toward the tissue.

Abstract: An optical inspection system for using laser-induced luminescence to detect the quality of organic materials, such as peanuts. The inspection system comprises an excitation means for illuminating a specimen to cause it to produce fluorescent radiation. The spectral representation of the fluorescence produced by the specimen is compared to a reference spectrum to obtain an indication of the physical characteristics of the specimen. In a preferred embodiment, the system identifies and removes peanuts contaminated with aflatoxin from a stream of peanuts by determining fluorescence at a predetermined wavelength.

Abstract: A noninvasive optical oximeter for measuring oxygen saturation of arterial blood. A sample of blood is illuminated with light at four different wavelengths. Light reflected by the blood is sensed by a photodetector and a plurality of output signals are created in response thereto. The reflected light at each of the four wavelengths is detected after contact with the blood and is correlated with the oxygen saturation of the patient's blood using mathematical relationships for arterial and venous oxygen saturation. The present invention provides a noninvasive backscatter oximeter which is capable of providing accurate indications of a patient's blood oxygen saturation without the need for obtaining prior information relating to the oxygen content of the patient's blood.

Abstract: A method and apparatus for optical diagnosis and treatment of abnormal cells through the use of hormone-specific chemical markers which are preferential to genital tissues. Abnormal cells can be differentiated from normal cells by the amount of fluorescent or thermal radiation produced by the chemical marker retained in the respective cells when irradiated with electromagnetic radiation at a predetermined wavelength. Once the abnormal cells have been detected, they can be treated through the use of an optical technique based on photochemical or thermal reactions which can be controlled to destroy the abnormal cells, while leaving normal cells unharmed.

Abstract: Method and apparatus for vertical strip clad overlay welding. The method comprises matching the vertical travel of a special welding shoe to an appropriate amount of strip electrode melt-off necessary to maintain a preset molten pool level within a reservoir trough provided by the shoe. The welding shoe comprises a water cooled copper mold for forming the weld bead and a ceramic insert connected to the mold for providing the reservoir trough. Apparatus for correlating the vertical travel speed of the shoe with the strip electrode melt-off is disclosed. Apparatus for applying a plurality of successive weld beads to a vertical vessel wall is also disclosed.

Abstract: An improved blood pressure occlusion cuff which is easily attached to the patient's arm and which is comfortable for use over extended periods of time. The preferred embodiment of the invention blood pressure cuff comprises a flexible band, a buckle for releasably securing said band to a person's limb, structure for pressurizing said band to cause it to apply pressure to said limb and for sensing pressure variations related to the flow between said buckle and said limb when said band is secured to said limb.

Abstract: A universal accumulator for utilization in an automotive air conditioning system. An inlet fitting and an outlet fitting are connected to the top of the accumulator housing. The adjustable connection of the outlet fitting to approximately the center of the housing top permits the variable positioning of the outlet port relative to the inlet port and utilization of the accumulator in a wide variety of automobile applications. A method for replacing an accumulator with the universal accumulator of the present invention is also disclosed.

Abstract: A method for computing optimal hold down pressure for a transducer comprising an array of pressure sensing elements for generation of electrical waveforms indicative of blood pressure in an artery. Using the selected pressure sensing element that is determined to be positioned substantially over the center of the underlying artery, a set of data corresponding to the diastolic pressure and the pulse amplitude pressure is collected and stored. The diastolic pressures and pulse amplitude pressures are taken as a function of hold down pressure over a range of hold down pressures between the pressure at which the artery is unflattened and the pressure at which the artery is occluded. First and second polynomials are fitted to the diastolic pressure data set and the pulse amplitude data set, respectively. The hold-down pressure at the point of minimum slope of the first polynomial fitted to the diastolic versus hold-down pressures values provides one estimate of the correct hold-down pressure.

Abstract: A method and apparatus for collecting measurements on the surface of the earth in a form which can be processed to obtain enhanced resolution of subsurface resistivity anomalies in the earth's geologic structure. The system of the preferred embodiment utilizes many separately acquired voltage and current measurements on the earth's surface in a superposition analysis to "synthesize" the condition whereby the many separate measurements are acquired simultaneously to give useful advantages in improved depth of investigation commonly known as focused resistivity measurements.

Abstract: A compact, low noise inflation system for pressurizing occlusion cuffs used in conjunction with automatic blood pressure monitoring equipment. In the preferred embodiment, an electric pump is controlled by a closed-loop, pressure feedback control circuit which compares the cuff pressure with a desired pressurization profile set by the user or stored in a memory device. Acoustic filters are connected to the intake and exhaust ports of the pump to attenuate the intensity of acoustic noise and pressure waves to allow accurate detection of oscillometric pulse data by the blood pressure monitoring system.

Abstract: A system for automatically positioning a blood pressure monitor transducer in a desired position relative to an underlying artery. The positioning system comprises a positioniong motor which drives a gear assembly. The gear assembly is operatively engaged with a lead screw having a follower mounted thereto in threaded engagement therewith. The follower is secured to a strap which is routed through a roller system. As the motor is activated in response to output signals from the sensor mounted within transducer housing, the lead screw will rotate, thereby effectuating lateral movement of the transducer housing and sensor along a path defined by the strap.