Detection of Rotation Angles on Image Separation Problem

When two trains travel along the same track in the same direction, it is a common safety requirement that the trains must be separated by at least two signals. This means that there will always be at least one clear section of track between the two trains. If the safe-separation condition is violated, then the driver of the following train must adopt a revised strategy that will enable the train to stop at the next signal if necessary. One simple way to ensure safe separation is to define a prescribed set of latest allowed section exit times for the leading train and a corresponding prescribed set of earliest allowed section entry times for the following train. We will find strategies that minimize the total tractive energy required for both trains to complete their respective journeys within the overall allowed journey times and subject to the additional prescribed section clearance times. We assume that the drivers use a discrete control mechanism and show that the optimal driving strategy for each train is defined by a sequence of approximate speedholding phases at a uniquely defined optimal driving speed on each section and that the sequence of optimal driving speeds is a decreasing sequence for the leading train and an increasing sequence for the following train. We illustrate our results by finding optimal strategies and associated speed profiles for both trains in some elementary but realistic examples.

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Factors that Affect Depth Perception in Stereoscopic Displays

Human Factors The Journal of the Human Factors and Ergonomics Society ◽

10.1177/001872089203400602 ◽

1992 ◽

Vol 34 (6) ◽

pp. 655-667 ◽

Cited By ~ 46

Author(s):

Robert Patterson ◽

Linda Moe ◽

Tiger Hewitt

Keyword(s):

Depth Perception ◽

Exposure Duration ◽

Stimulus Size ◽

Viewing Distance ◽

Stereoscopic Displays ◽

Long Duration ◽

Image Separation

This study investigated several factors that affect depth perception in stereoscopic displays: half-image separation magnitude, separation direction (crossed vs. uncrossed), viewing distance, stimulus size, and exposure duration. The depth perceived under various combinations of levels of these factors was compared with depth predicted by the geometry of stereopsis. Perceived depth in the crossed-separation direction was frequently close to predictions, such that increases in separation and viewing distance produced appropriate increases in perceived depth. Depth in the uncrossed direction was frequently less than that predicted, especially for small stimuli presented at a long viewing distance, with a large half-image separation, and/or with a brief duration. Thus depth in both crossed and uncrossed directions equaled predictions only for large stimuli exposed for a long duration.

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Monaural Versus Binaural Discrimination for Normal Listeners

Journal of Speech and Hearing Research ◽

10.1044/jshr.0603.263 ◽

1963 ◽

Vol 6 (3) ◽

pp. 263-269 ◽

Cited By ~ 4

Author(s):

Richard G. Chappell ◽

James F. Kavanagh ◽

Stanley Zerlin

Keyword(s):

Single Channel ◽

Normal Hearing ◽

Dual Channel ◽

Recording Session ◽

Monosyllabic Words ◽

Image Separation ◽

Test Materials ◽

The Difference

Normal hearing adults demonstrated approximately 20% better intelligibility scores for monosyllabic words presented binaurally (with a background of conversation) than to these words presented monaurally. The test materials were recorded on dual-channel tape through two head-mounted microphones. These microphones were directed toward each of three speakers who in turn produced the monosyllabic words while two simultaneous conversations were carried on by four other participants. Throughout the recording session the experimenters attempted to preserve as naturalistic a situation as possible. The 18 subjects with normal hearing listened through earphones to a single channel of this tape presented monaurally and to both channels delivered binaurally. The difference between the monaural and binaural intelligibility scores is discussed in terms of image-separation in space.

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