Abstract: An apparatus and method for dynamically controlling the generation of radiation pulses during pulse-type fluoroscopic imaging. Brightness of an image produced by a pulse is detected, converted to a digital value and compared to an acceptable predetermined value range. If the brightness is not acceptable, the pulse rate is reset to a predetermined, relatively fast rate and the energy level for the next pulse adjusted up or down to increase or decrease the brightness as necessary. Once the brightness is found to be acceptable, the pulse rate is returned to the original pulse rate. If it is determined that motion is occurring, the pulse rate will increase to the relatively fast predetermined pulse rate to provide substantially real-time imaging. If the brightness becomes unacceptable for a pulse during the period of motion, the energy level for the subsequent pulse will be adjusted.

Abstract: A melt indexer system for determining the melt index of a plastic by testing. The melt indexer system comprises a plurality of melt indexers, each of the melt indexers including a melt chamber into which a sample of plastic to be tested is placed, a heater for melting the sample to a predetermined temperature and a test piston for extruding the melted sample through a calibrated orifice of a removable die to determine the viscosity of the sample as a function of its temperature. A robot arm and a computer programmable to control the movement of the robot arm are provided. An infeed queue holds in predetermined order a plurality of containers containing samples to be tested and a bar code reader identifies each sample to be tested. A test computer associates a particular sample with a predetermined plan for testing the sample, records and processes the melt index test results. A vacuum sipper extracts a charge of the sample from the sample container and places it in the melt chamber.