Abstract: A relatively large diameter core barrel has a plurality of diamond cutting elements disposed around the circumference of its working end for drilling piles in very hard ground, such as metamorphic rocks and igneous rocks. Each cutting element is designed for quick and simple replacement in the field. The cutting elements are of diamond composition, and provide a substantially flat cutting face for cutting principally through abrasion at the interface of the cutting element and the hard ground to be drilled.Piles are constructed using the diamond-tipped core barrel by first drilling an annular kerf in the ground. Circulating drilling fluid cools the diamond cutting elements and washes cuttings from the kerf during drilling. The drilled core may be removed, or it may remain in situ, with the kerf being filled by cementitious material or by a structural steel casement to form a very strong pile.

Abstract: A vacuum pump useful in penile erection systems is provided. The vacuum pump comprises a piston in a cylinder with intake and exhaust valves. The vacuum producing outstroke is powered by a spring having sufficient force to draw a vacuum no higher than the desired upper safety limit, and the reset stroke is powered manually. The pump is constructed to provide an inherent vacuum limit by selecting a spring which, when fully compressed during a reset stroke, exerts a force against the piston which is less than the force exerted against the piston head by the differential pressure between atmospheric pressure and a preselected maximum vacuum pressure inside the cylinder. Thus, when the maximum vacuum pressure is reached, the piston is not returned for successive pumping.

Abstract: A method for energy conversion and storage includes the steps of providing a supply of processed natural gas. The natural gas is compressed and stored in a sub-surface storage reservoir. The compressed natural gas is then delivered from the reservoir to an electrical power generator to thereby generate electrical energy.

Abstract: An electronic stethoscopic system is described which permits detection of auscultory sounds in a patient in high noise environments such as ambulances and aircraft. The stethoscope employs an electroacoustical transducer, an acoustical driver mounted in a headset providing acoustical isolation from exterior noise, a summing microphone positioned within the insulating headset, and active noise reduction circuitry to feed an error signal back from the summing microphone to the acoustical driver so as to effectively cancel the unwanted acoustical noise originating external to the insulating headset. The stethoscopic system includes circuitry permitting the headset to selectively receive the audio output from a vehicular intercom system whenever a voice signal is present, thereby allowing treating medical personnel to monitor the patient while participating in the conversation being conducted on the vehicle's intercom system.