Abstract: The present invention includes a fiber optic seal (2) including a transparent seal body (4) having two spaced apart cavities (12,14,52,54) formed therein. Both ends (36,38) of a fiber optic cable (28) are respectively secured within the spaced apart cavities (12,14,52,54). A microprocessor-based electronic verifier (60) injects light into one of the cable ends (38) via a plurality of illumination light guides (20) fixed within the seal body (4) between an external surface (6) thereof and the illumination cavity (12). Light emitted from the remaining end (36) of the fiber optic cable (28) is transmitted from the detection cavity (14) to the exterior surface (6) of the sealed body (4) via a plurality of detection light guides (24) fixed within the seal body (4). Thereafter, the light is measured and converted by the electronic verifier (60) to provide a seal signature.

Abstract: The present invention provides a method and detection system for determining whether a person or other animate body is present in a vehicle by analyzing the power of the output signal from a geophone placed in contact with the vehicle structure. First an electrical signal is obtained which is a function of the vibrations emanating from the structure, and this signal is sampled on a contiguous basis over a plurality of time periods of equal duration. From these samples, a determination is then made as to whether a dense accumulation of power exists in the vicinity of the lowest power point of the sampled time periods and whether this lowest power point is above a predetermined minimum level. The system for accomplishing this method may include a seismic transducer used as a sensing device and a micro-computer for processing the output signals from the seismic transducer. The micro-computer will, on a continguous basis, sample about 22/3 seconds of data at a time.

Abstract: The present invention comprises a short-pulse radar guidance tool which determines borehole-to-roof and borehole-to-floor distances along a coal seam by measuring the travel times of electromagnetic pulses transmitted from the tool and reflected back to a receiving antenna in the tool from the interface at the roof or floor of the coal seam. The tool includes a high frequency electromagnetic pulser, a directional transmitting antenna, a directional receiving antenna, a battery power source, and control circuitry for performing all control and transmitting/receiving functions at the tool location. Placement of the transmitting antenna at a point intermediate the control circuitry and the receiving antenna acts to reduce indirect electromagnetic coupling between the antennas. Circuit isolators are used to further attenuate RF crosstalk occuring between the control circuitry and the receiving antenna.

Abstract: This invention relates to pulse radar detection of targets in extended media, including natural phenomena such as oil, coal and ore deposits within the earth. In particular, this invention relates to a pulse radar system employing a synthetic pulse formed from a Fourier spectrum of frequencies generated and detected by a digitally controlled transmitter and receiver circuits.

Abstract: A method and apparatus for railroad track surveying for accurately determining track gauge includes a pair of electro-optical sensors which are situated completely above the rail head level. A collimated light source in each sensor projects a narrow light pattern containing a substantial vertical component downwardly against the gauge surface of the rail. An optical system in the sensor collects an image of the pattern and focuses it upwardly along an object axis to a focal plane. A detector in said focal plane is responsive only to that portion of the image which appears at a juncture of the focal plane with an object plane which includes said object axis and extends laterally thereof in directions parallel to the plane of the rail heads and intersects the gauge surface at a point five-eighths of an inch below the running surface when the rail head is at its nominal position.