• Korean Journal of Cognitive Science
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• v.23 no.3
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• pp.409-424
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• 2012

The purpose of the present study was to examine if perception of visual coordination pattern is consistent with the prediction of the HKB model (Haken, Kelso, Bunz, 1985). In addition, this study aimed to see if an additional sensory information using a grid background stabilizes perception of coordination pattern. Participants joined one of two experimental groups, Normal background and Grid background, to participate the pattern recognition training session and the pattern judgment test session. Participants observed $0^{\circ}$, $18^{\circ}$, $36^{\circ}$, $54^{\circ}$, $72^{\circ}$, $90^{\circ}$, $108^{\circ}$, $126^{\circ}$, $144^{\circ}$, $162^{\circ}$, and $180^{\circ}$ coordination patterns characterized by two oscillating dots. The dots oscillated in 0.25 Hz for the pattern recognition training and in 0.5 Hz, 1 Hz, and 2 Hz for the pattern judgment test. Judgment score, absolute judgment error, and judgment stability out of the pattern judgment test were analyzed statistically. The landscape of pattern accuracy and stability data was "inverted-U" shape with slower oscillating frequency conditions. In the faster condition, the accuracy and stability of the judgment decreased with relative phase patterns near $180^{\circ}$. These findings consistent with the prediction of the HKB model. The grid as additional sensory information did not increase accuracy and stability in coordination perception.

• Progress in Medical Physics
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• v.4 no.2
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• pp.37-47
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• 1993

The quality of radiation for a high energy x-ray beam can be specified by its attenuation curve in a selected material. The inverse Laplace transform of the attenuation curve can be used as an approximate indication of the energy spectrum of the beam. We have made a comparative investigation of the estimated spectrum obtained by the Laplace transform analysis of the transmitted exposure data measured in an absorption study of a 6MV x-ray beam. Two of existing transform pair models have been investicated and discussed.