Abstract: A synchronous time division multiplexing system for multi-channel calls involves dividing each frame into a first segment and a second segment each containing substantially the same number of time slots and dividing the number of channels of the multi-channel call into a first subset and a second subset each containing approximately the same number of channels. Thereafter, the first subset is assigned to the first segment of the first frame and the second subset to the second segment of the first frame. The invention involves in a first time switching stage transposing the first subset to the second segment of the first frame such that the channels within the first subset occupy eligible free slots and retain their relative order and transposing the second subset to the first segment of the next frame such that the channels within the second subset occupy eligible free slots and retain their relative order. The call subsets are thus transported during a single stage of time switching.

Abstract: A resilient, yieldable, nestable, tapered, foamed thermoplastic container or cup is provided each cup or container having an endless groove and endless lug extending from the inside and outside surfaces of the container or cup wall, the groove penetrating the container or cup wall. The endless lug extends a distance from the cup wall greater than the distance the groove penetrates into the cup wall by about several thousandths of an inch (a few thousandths of a centimeter).