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Document Type

Research

Abstract

Records have shown that nearly 3,089 grade crossing accidents occurred in the United States in 1938. Of this number 1,450 occurred at night. Equating for volume of traffic and miles of travel, about 65 per cent of train-automobile accidents occur at night. Additional data indicate that the chances of a car driving into a train at night are about 9 times greater than in daylight. Of the estimated $3,000,000,000 annual economic loss to the country through automobile accidents it is shown that night driving costs about $1,200,000,000, although only 25 per cent of the driving is done during this period of the day. Research techniques are described which have been devised to analyze the physical factors of the luminant and electrical system of the car, as well as the psychological factors involved in seeing under conditions of low illumination. Results from a series of these studies are summarized in which it is shown that the visibility function is not constant throughout the acuity range although acuity varies with the logarithm of the stimulus. The constants are different for high and low ranges of acuity.

Publication Date

1941

Journal Title

Proceedings of the Iowa Academy of Science

Volume

48

Issue

1

First Page

395

Last Page

396

Copyright

© Copyright 1941 by the Iowa Academy of Science, Inc.

Language

EN

File Format

application/pdf

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