Abstract: A computer storage management system establishes a subpool of available blocks of one size from a multiplicity of different storage frames. The available blocks are queued in the subpool. A garbage collection routine periodically or occasionally determines which of the frames having blocks on the subpool queue are completely available based on the number of available blocks on the queue for each frame. Then, the garbage collection routine removes from the queue and thereby reclaims the blocks of the frames which are completely available. The garbage collection routine also requeues the blocks from the other frames such that the blocks of these other frames are clustered with the other blocks of the same frame. Blocks are allocated from the front of the queue. Blocks of the one size from frames other than those represented at or near the end of the queue are returned to the front of the queue after use.

Abstract: The invention is an improvement to the linear array transducer and the annular array transducer. The improvement lies in the invention's capability to produce a phase shifted wave across each segment of the composite transducer and in so doing, better match the ideal phase shift for aiming or focussing acoustic waves.The invention comprises transducer segments which each have at least one resistive electrode; the other electrode may be a standard highly conductive one. An electrical drive signal is applied to one border of each resistive electrode, and as the electrical drive signal propagates across the resistive electrode, it interacts with the capacitance of the piezoelectric element below and has its phase gradually shifted. As a result, the transducer segment produces an acoustic wave which has gradually varying phase, and this varying phase approximates the curvature of the ideal phase shift pattern.

Abstract: A switch circuit is disclosed which warms-up a load prior to complete turn on. The circuit includes a single pole double throw switch and an amplifier. The input to the amplifier connects to the off throw of the switch and the amplifier is rendered nonconducting when the switch is off. However, when the switch is between its off and on position, as it is being thrown on, the amplifier conducts a half wave rectified warm-up current to the load. Then, when the switch is on, the amplifier is bypassed by a short circuit connecting between the on throw terminal of the switch and the load, and the load is driven to 100% capacity via this short circuit.

Abstract: The invention is an improved piston engine, either two stroke or four stroke. In one, two stroke, one cylinder embodiment, the improvement comprises two springs connecting between the piston and the base of the piston. These springs are relatively relaxed when the crank is at top dead center. Then during the power/intake stroke, some of the fuel's energy is delivered to the crankshaft and some is used to compress the springs. The stored energy in the springs is delivered to the crankshaft during the exhaust/compression stroke while the springs return to their relatively relaxed condition. As a result, energy is delivered to the crankshaft during both strokes of the cycle, and the engine runs smooth.In one, four stroke, two cylinder embodiment, each cylinder has springs as described above, the cranks of each cylinder are aligned, and the cam sets one cylinder in the power stroke while the other is in the intake stroke.

Abstract: The invention is an apparatus useful in ultrasonic imaging to provide a highly focussed wave with a large depth of field. The apparatus comprises two or more coaxial, curved transducers, each producing adjacent, coaxial fields.

Abstract: The invention is useful in the field of diagnostic ultrasound to improve the axial resolution of an image. One embodiment comprises a transmitted, ultrasonic wave with two parts. The first part interacts with a specimen to initiate an echo, and the second part arrives out-of-phase with the ringing of the specimen and interferes to suppress the ringing. Another embodiment comprises a transmitted, electrical signal with two parts which interact as described above to cause a piezoelectric transducer to produce a transmitted, ultrasonic wave with truncated ringing.

Abstract: The invention is a transducer which acts with an acoustical lens to produce a highly focussed beam and attenuated side lobe waves. The transducer comprises a resistive electrode which attentates electrical signals applied to and emanating from the peripheral region of the transducing element.

Abstract: The invention provides a highly focussed ultrasonic wave throughout a large depth of field without any mechanical motion. One embodiment of the invention providing two focussed fields includes a front to back arrangement of a converging lens, a transducer without any backing material to dissipate ultrasound, a converging lens, and a transducer. To focus in the far field, the front transducer transmits and receives via the front lens. To focus in the near field, the rear transducer transmits and receives via both lenses which collectively focus in the near field.