NCJ Number
58398
Date Published
1978
Length
7 pages
Annotation
THE RESULTS OF AN EXAMINATION OF AN EXPERIMENTAL AUTOMATIC GAMMA RAY SCREENING SYSTEM FOR THE DETECTION OF VARIOUS FORMS OF EXPLOSIVES CONCEALED IN CHECKED AIRLINE BAGGAGE ARE PRESENTED.
Abstract
THIS EXPERIMENTAL DETECTION DEVICE WAS DEVELOPED BY THE WESTINGHOUSE RESEARCH AND DEVELOPMENT CENTER, UNDER CONTRACT TO THE FEDERAL AVIATION ADMINISTRATION. IN THE PRESENT SYSTEM THE DETECTION CRITERIA USED ARE SIMPLY THE AREA OF THE LARGEST OBJECT FOUND IN THE BAG AT THE PREPROGRAMMED TRANSMISSION THRESHOLD. TO DETERMINE THE EFFECTIVENESS OF THIS CRITERION (AND OTHERS), A SYSTEM WAS USED TO RECORD TRANSMISSION VALUES OBTAINED AT NEWARK, N.J., AND WASHINGTON, D.C., NATIONAL AIRPORT ON A LARGE NUMBER OF CHECKED AIRLINE PASSENGER BAGS. DURING NORMAL OPERATION, THE SYSTEM IS AT ALL TIMES UNDER THE CONTROL OF A SYSTEM OPERATING PROGRAM RESIDENT IN A LSI-11 COMPUTER. THE HEART OF THE SYSTEM OPERATING PROGRAM IS THE ANALYSIS OF THE GAMMA RAY TRANSMISSION VALUES TO YIELD A COMPLETE OBJECT SIZE DISTRIBUTION FOR THE CONTENTS OF THE BAGS. THE IMAGE IS THRESHOLDED TO FORM A BINARY PICTURE WHICH IS ANALYZED TO YIELD THE SIZE DISTRIBUTION OF ALL DISCRETE OBJECTS PRESENT AT THE SELECTED TRANSMISSION THRESHOLD. IN THE PRESENT SYSTEM, THE PRESENCE OR ABSENCE OF AN EXPLOSIVE THREAT IS DETERMINED SOLELY ON THE BASIS OF THE SIZE OF THE LARGEST OBJECT IN THIS DISTRIBUTION. A NUMBER OF AREAS OF POSSIBLE IMPROVEMENT IN THE IMAGE ANALYSIS SOFTWARE REMAIN TO BE EXAMINED. HOWEVER, THE FEASIBILITY OF A FULLY AUTOMATED BAGGAGE INSPECTION SYSTEM TO REPLACE CURRENT MANNED X-RAY IMAGING SYSTEMS HAS BEEN DEMONSTRATED. SYSTEM ILLUSTRATIONS AND REFERENCES ARE PROVIDED. (KCP)