Abstract: Ultrasonic detection of early pregnancy in sows and like animals is enhanced by basing an assumption of pregnancy upon detection of a substantially echo-free animal zone of predetermined width or greater which may occur over a substantial range of animal depths, combined with detection of a distinct echo from a greater depth than the echo-free zone.

Abstract: Trains of echo signals occurring from repetitively transmitted ultrasonic pulses are stored in a shift register in accordance with their times of occurrence, and the stages of the shift register are connected to illuminate respective light-emitting diodes arranged in a linear array, providing a display indicating the depths of density changes in animal matter or the like being inspected.

Abstract: Articles such as glass jars filled with food products are inspected for defects by scanning an x-ray image to provide video signals which are processed in a novel manner to provide increased sensitivity to detect very small foreign particles without decreasing a tolerance for normal variations, to inspect substantially the entire contents of a container such as a jar even if it has a varying diameter, without the need for precise positioning of the articles within an inspection zone, and without a need for an x-ray or optical mask tailored to fit each type of jar to be inspected.