Online ISSN : 1349-838X
Print ISSN : 0019-2341
ISSN-L : 0019-2341
Volume 97 , Issue 8A
Showing 1-4 articles out of 4 articles from the selected issue
Original Paper
  • Byoungwoo Ko, Takaaki Koga, Bin Lu, Kotaroh Hirate, Masaaki Mizuno, Na ...
    2013 Volume 97 Issue 8A Pages 429-435
    Published: August 01, 2013
    Released: October 31, 2013
    We assume that when people look around an entire space, the total impression is created through the accumulation of visual information in every direction. We define "brightness of a space" and examine the impact factors and quantification. The results of previous studies suggest that it is reasonable to use average luminance and luminance contrast. However, when the entire space is defined as "brightness of a space", luminance contrast cannot be applied. For this reason, we consider the physical quantity that shows the variation of the brightness in our evaluation experiment on Brightness. It is possible to propose using a prediction equation of " brightness of a space" using the standard deviation of the logarithm of the luminance values and average luminance.
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Research Note
  • Yoko Harada, Yamamoto Haruhiko, Kiyoshi Iwaya, Nanae Kaneko
    2013 Volume 97 Issue 8A Pages 436-441
    Published: August 10, 2013
    Released: October 31, 2013
    In agriculture, particularly wet rice cultivation, light pollution caused by exterior illumination at night interferes with dark periods and results in delayed flowering (heading). However, we found that by selecting the wavelength of light sources to which rice is exposed and controlling the luminescence, it is possible to bring the time of heading closer to that of a control plot (total darkness). In this study, visibility of artificial illumination using mixed LED (blue, green, yellow-green) was evaluated by comparing it with green LED and white LED illumination. We evaluated five items in this experiment: pedestrian behavior, facial recognition, color recognition, peripheral visual field, and impression. We found that the evaluation for ‘color recognition’ and ‘impression’ were lower for mixed LED than for white LED illumination. Therefore, it is suggested that mixed LED illumination needs to improve in these items.
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