Division (mathematics)

About: Division (mathematics) is a research topic. Over the lifetime, 12717 publications have been published within this topic receiving 87814 citations.

Relational division: four algorithms and their performance

Abstract: Three known algorithms for relational division, the algebra operator used to express universal quantification (for-all conditions) and an algorithm called hash-division are outlined. By comparing the algorithms analytically and experimentally, it is shown that the algorithm provides performance competitive with or superior to that of techniques used to date, namely techniques using sorting or aggregate functions. Furthermore, the algorithm can eliminate duplicates in the divisor on the fly, ignores duplicates in the dividend, and allows two kinds of partitioning, either of which can be used to resolve hash table overflow or to efficiently implement the algorithm on a multiprocessor system. >

Taken-image signal-distortion compensation method, taken-image signal-distortion compensation apparatus, image taking method and image-taking apparatus

Abstract: Disclosed herein is a method of compensating a signal of an image of one screen for distortions in the horizontal and/or vertical directions of a screen of the image. The method includes the steps of: dividing one screen area of the image into a plurality of picture divisions; and detecting a movement vector of the image for each particular one of the picture divisions from information on a difference in image between the particular picture division on one of two screens and the particular division on the other of the two screens. The method further includes the steps of: finding a difference in the detected movement vector between any specific picture division and a picture division adjacent to the specific picture division in order to detect a velocity of a change in image distortion for the specific picture division; and compensating the image for a distortion for each of the picture divisions on the basis of a velocity detected for each of the picture divisions as the velocity of a change in image distortion.

Time division exchange for carrying out a loop-back test

Abstract: A time division exchange interchanges predetermined time slots of a time division multiplexed signal and returns it to a network (1) during a loop-back test. A buffer memory (150 or 160) in a time division multiplexed trunk (120) may be used to interchange the predetermined time slots. Alternatively, the buffer memory may be provided in a return loop (21') for use during the loop-back test. Therefore, it can be determined that the received signal is sent from another exchange and the loop-back test can be performed using ordinary exchanging processing procedures.