Abstract: A method for fast inverse planning of IMRT treatment plans is disclosed. The method relies on a computationally efficient algorithm for evaluating the gradient of a general class of objective functions, and also on the efficient optimization that is realized due to the directional conjugacy of the objective functions. Several types of clinically relevant objective functions that belong to this class are described. The computational evaluation relies on operations that are commonly used for signal- and image-processing, and so can benefit from a number of well-known acceleration techniques.

Abstract: An adapter for an eight track cartridge playing machine having a transfer roller to engage the conventional capstan and suitable motion transmitting means to drive an upright capstan in a cassette housing. Playback heads are carried on a carrier which may be raised or lowered to the desired level in accordance with which of a vertical bank of cartridge receivers is to be activated. Two cartridges are carried in each receiver and the receivers are independently pivotable so that a control knob may be turned to pivot the receiver and bring the selected cartridge into engagement with the drive capstan, and into operative association with the selected playback head.

Abstract: A chalk line dispenser comprising a drive casing and a replacable reel casing, which are joined to form a complete assembly. The drive casing includes a shaft and a coil spring-powered drive therefor, with a thumb-operated lever for releasing a clutch to enable spring reeling of the line. The shaft extends from the drive casing in square cross-section and is engaged by a complementary opening in the reel. The reel casing carries the reel and powdered chalk, and includes a ledge over which the chalkline passes when being reeled into the casing. A squeegee carried on the thumb operator of the clutch release presses the chalkline against the ledge to squeeze any moisture from it, causing same to drop into a moisture sump carried below the ledge. A desiccant may be carried in the moisture sump and/or may be mixed with the powdered chalk itself.

Abstract: An automatic pet feeder has several troughs, each with a lid hinged thereto. A T-shaped cam follower extends from each lid and rides against a cylindrical cam tube which makes a single revolution during the feeding period. I-shaped slots each extend partially around the tubular cam through a selected arc so that it underlies its associated cam follower at a desired time, wherein biasing means force the lid upward to swing the cam follower completely through the slot and hold the lid in open position.