Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Yasuko Koga Last modified date:2020.01.10

Associate Professor / Environmental Engineering, Planning and Design Section / Department of Architecture and Urban Design / Faculty of Human-Environment Studies


Papers
1. Yasuko Koga, Yasufumi Shigetomi, Keisuke Yoshida, Kazuhiro Hiyoshi, Kouki Zen, Switching to LED Lighting for Container Terminals - Demonstrative experiments on lighting quality and reliability, Proc. of BalkanLight 2018, 125-131, 2018.06, A three-year course of demonstrative experiments on LED lighting was conducted in a container terminal in operation for high-mast lighting and gantry cranes. Photometric measurement and workers evaluation showed its advantages in spatial brightness, visibility and colour appearance. But, the need for glare control was found. The experiments demonstrated importance of lighting design with zoning of the container yard, appropriate specifications of the LED lights, and requirements for reliability of the trolley lights..
2. Yasuko Koga, Masahiko Yamakawa, Potential Non-Image-Forming Visual Effects of Violet-LED and Blue-LED White Light Sources, Proc. of BalkanLight 2018, 17-21, 2018.06, Intrinsically photosensitive retinal ganglion cells (ipRGCs) contribute to non-image-forming visual effects of light in humans with inputs from rods and cones in the retinal circuit. Irradiance ratios for ipRGC and for photopic vision were defined with the ipRGC spectral sensitivity in CEN/TR 16791 and the photopic luminous efficiency, V(λ) respectively. From measurements of spectral irradiance, potential for inducing non-image-forming visual effects was evaluated for two types of phosphor-converted white LED light source, that is, a violet-LED excitation type and a blue-LED one. Chromaticity was adjusted to be as identical as possible between the two types. Irradiance ratio for ipRGC was almost the same between the two types having the same correlated colour temperature. This paper is an interim report on luminous properties of the two types of LED..
3. Han Li, Tomoko Koga, Yasuko Koga, Development of an Autonomous Sun-Shading Device Integrated with High Efficient Office Lighting, Proc. of CIE 2018 "Topical Conference on Smart Lighting", 10.25039/x45.2018.OP07, 34-42, 2018.04.
4. Yasuko Koga, Keisuke Yoshida, Yasufumi Shigetomi, Kazuhiro Hiyoshi, Kouki Zen, LED Crane Lighting to Hoist Sustainability of Container Terminals, Proc. of the 8th Lux Pacifica, Life and Lighting, 2018.03, In recent years, LED lighting has been introduced into port facilities to improve energy efficiency and to reduce energy and maintenance costs. This research work examined performance of LED lights for gantry crane lighting through experiments and subjective evaluations in a container terminal in operation. Measurement was done on illuminance and luminance distributions of the illuminated area, and vibrations that occurred when trolleys were moving. Questionnaire surveys were conducted with crane operators and relevant workers on the visual environment and workability. It was found that a narrow-angle type is suitable for the LED trolley lights to properly illuminate the task area. In wet weather, workers preferred a light colour of 3000 K for control of glare by reflection from wet surfaces. LED trolley lights should last a practical lifespan of 30 years or more. To meet this requirement, they should pass vibration testing in X, Y and Z axial directions under conditions of frequencies from 10 Hz to 500 Hz, the acceleration of 5 G and 10 sweep cycles, and shock testing downwards and upwards under conditions of the peak acceleration of 10 G, half sine shock with a 16-millisecond duration and 5000 pulses..
5. Han Li, Tiange Wang, Yasuko Koga, Detection of Sunshine on Windows by Vertical Global Illuminance - Utilization of ISO/CIE Standard General Skies, Proc. of the 8th Lux Pacifica, Life and Lighting, 2018.03.
6. Kazuki Miyashita, Yasuko Koga, Kotaro Noguchi, Masahiko Yamakawa, Comparative Assessment of Colour Rendering Properties Between Violet-LED and Blue-LED White Light Sources, Proc. of the 8th Lux Pacifica, Life and Lighting, 2018.03.
7. Han Li, Tomoko Koga, Yasuko Koga, Individual autonomous blind control system with PV-slat sensors, Proc. of Advanced Building Skins 2017, 2017.10.
8. Yasuko Koga, Koichi Kitamura, Kazuki Miyashita, Masayuki Kimura, Quantitative Assessment of Perceptual Luminous Uniformity of OLED and LED Panels for Rear Lights, Proc. of the ISAL 2017, 2017.09, OLED lighting panels have a uniform and soft luminous appearance, whereas LED lights have a grainy luminous appearance without light diffusing measures. In contrast to red OLED rear lights, red LED rear lights tend to give irritating and discomfort impressions at dusk and night. Thinking that the soft luminous appearance of the OLED lights is due to their luminance evenness, this research work assessed the appearance of different lumi-nous panels including OLED and LED lighting panels. Luminance distributions of the luminous panels were estimated from their digital images and analysed using the spatial frequency analysis. Perceptual luminous uniformity or non-uniformity was read from power spectra at low spatial frequencies. This research work proposes the ratio of the average power in the range of low spatial frequencies to that in the range of middle spatial frequencies as an index of perceptual luminous uniformity..
9. Yasuko Koga, Keisuke Yoshida, Yasufumi Shigetomi, Tamotsu Ninomiya, Kazuhiko Egashira, Towards The New Generation of Lighting Design for Advanced Container Terminals, Proc. of CIE 2016 Lighting Quality and Energy Efficiency, 2016.03, In order to realize eco-friendly advanced container terminals, introduction of LED lighting is considered to be an effective measure. This research work conducted demonstrative experiments in a container yard in operation to assess effectiveness and reliability of high-powered LED luminaires and effects of LED lighting on cargo handling operations. Measurements and surveys proved that LED lighting improves working environments in comparison with conventional high-pressure sodium lighting. But, glare control was found to be an issue. The demonstrative experiments revealed that a new method of lighting design is necessary for efficient and effective lighting in advanced container terminals. This research work proposes a concept of diversified lighting. It comprises zoning of the container yard, proper use of high-mast lighting and illumination by cargo handling machines, and supplementary security lighting. It will achieve what is called the right light in the right place..
10. Yasuko Koga, Kosuke Takao, Naotaka Saita, Effects of Cutting Light in a Wavelength Range on Discomfort Glare, Proc. of the 11th International Symposium on Automotive Lighting, 2015.09.
11. Yasuko Koga, Naotaka Saita, Spectral Effects of Light on Discomfort Glare under Mesopic Conditions, Proc. of the 28th CIE Session, 2015.06.
12. Yasuko Koga, Yasuhiro Miki, A Review of Historical Changes in Japanese Regulations and Standards for Sunlight and Daylighting, CIE Centenary Conference "Towards a New Century of Light", 2013.04.
13. Y. Koga, M. Takao, T. Murata, N. Ide, I. Mikuriya, G. Yamashita, A Pilot Experiment on Spectral Response Sensitivity of the Suprachiasmatic Nucleus (the Chief Circadian Pacemaker), 27th Session of the CIE, Vol.1, Part 1, 2011.07.
14. Y. Koga, T. Iwata, N. Ide, An Approach to Evidence-Based Design of The Luminous Environment in Hospitals - Surveys on nurses' work and sleep, CIE 2010 "Lighting Quality and Energy Efficiency", 2010.03.
15. Y. Miki, Y. Koga, E. Mochizuki, T. Iwata, Y. Kojima, M. Fujino, T. Kotani, A. Mori, T. Yagi, Development of a Comprehensive Evaluation System for Lighting Environment Efficiency, CIE 2010 "Lighting Quality and Energy Efficiency", 2010.03.
16. Yasuko Koga, Motoharu Takao, Light Response Properties of Intrinsically Photosensitive Retinal Ganglion Cells in Non-Image-Forming Vision, Light and Lighting 2009, 2009.05.
17. K. Wonwoo, Y. Koga, I. Shin, Evaluation of Discomfort Glare from Daylight, 26th Session of the CIE, Vol.2, D3-170 - D3-173, 2007.07.
18. Y. Ogiuchi, K. Satozaki, Y. Koga, Environmental Brightness Estimation for Asymmetrically Illuminated Space, 26th Session of the CIE, Vol2, pp.D3-213 - D3-216, 2007.07.
19. Wonwoo Kim, Yasuko Koga, Masayasu Hara, A method for evaluating discomfort glare from windows
Part 2. Discomfort glare from large glare sources with non-uniform luminance, Shomei Gakkai Shi, 10.2150/jieij.91.69, 91, 2, 69-77, 2007.05, A new formula is proposed for evaluating discomfort glare from large glare sources with non-uniform luminance. Three types of experiments were conducted using a modal window divided into two parts. Each part of the window had different luminance. First, the luminance ratio was measured when the observers perceived the difference of luminance between the two parts. The result of the measurement shows that the difference of luminance can be perceived when the ratio is 1:1.24. In the second experiment, the window was divided into two parts of the same size, and the degree of discomfort glare from the window was investigated. In the third experiment, the same test was conducted, but the window was divided into two parts with different size. The degree of discomfort glare was calculated using two methods. One used the average luminance of the window as a parameter, and the other summed up the degrees of discomfort glare from both parts of the window. There were no significant differences between the two methods. Consequently, a formula that uses the average luminance is proposed for evaluating the discomfort glare from large sources with non-uniform luminance..
20. Wonwoo Kim, Yasuko Koga, Masayasu Hara, A method for evaluating discomfort glare from windows
Part 1. A formula for evaluating discomfort glare from large glare sources with uniform luminance, Shomei Gakkai Shi, 10.2150/jieij.91.63, 91, 2, 63-68, 2007.05, A new formula is proposed for evaluating discomfort glare from large glare sources with uniform luminance. The formula has four parameters: luminance of the glare source, size of the glare source, background luminance and position index. An experiment was conducted to investigate the effect of each parameter on the evaluation of discomfort glare. Twenty subjects evaluated discomfort glare from the model window. The new formula shows the relation between the degree of discomfort glare and the parameters. The formula is distinct from other formulas in that it has a simple form and the background luminance has little effect on the degree of discomfort glare. It is expected that discomfort glare from large glare sources with uniform luminance can be appraised using the formula..
21. Yasuko Koga, Masayasu Hara, Application of All Sky Model to RADIANCE simulation program, LUX EUROPA 2005, 2005.09.
22. Wonwoo Kim, Yasuko Koga, Glare Constant Gw for the Evaluation of Discomfort Glare from Windows, Solar Energy, 10.1016/j.solener.2004.05.020, 78, 1, 105-111, 78-1, pp.105-111, 2005.01.
23. Wonwoo Kim, Yasuko Koga, Glare constant Gw for the evaluation of discomfort glare from windows, Solar Energy, 10.1016/j.solener.2004.05.020, 78, 1, 105-111, 2005.01, This research work has been carried out in effort to establish the evaluation method for the discomfort glare from windows. The existing Glare constant formulas are determined from the glare source located on the line of sight and the exponents in the formulas have fixed values through the entire visual field. In order to apply the existing Glare constant formulas to windows, it is necessary to confirm that the exponents have suitable values at the positions elsewhere on the line of sight. The experiments were conducted to obtain the precise exponents at various positions. Sensitivity to glare was tested on the Glare Testing Instrument consisting of a semi-spherical screen and the optical fiber lamp. Twenty-five observers aged between 20 and 47 had participated in the experiments. The results show that the exponents are variable according to the source position, source size, and background luminance. The modified Glare Constant Gw formula is proposed considering the variation of the exponents. The charts for determining the exponents of source size and background luminance are also proposed. The modified Gw, formula has the practical advantage in which the Glare Constant can be obtained directly at the position of the source..
24. Wonwoo Kim, Yasuko Koga, Effect of Local Background Luminance on Discomfort Glare, Building and Environment, 10.1016/j.buildenv.2004.05.003, 39, 12, 1435-1442, Vol.39, Issue 12, pp.1435-1442, 2004.12.
25. Wonwoo Kim, Yasuko Koga, Effect of local background luminance on discomfort glare, Building and Environment, 10.1016/j.buildenv.2004.05.003, 39, 12, 1435-1442, 2004.12, The objective of this research is to propose a practical method of determining the background luminance in the evaluation of discomfort glare. Two experiments were conducted, a visual sensitivity test and a glare sensitivity test. The results show that the luminance of threshold and the luminance of discomfort glare are mainly determined by the luminance of the immediate background of the source, rather than by the average background luminance, which has previously been suggested by unified glare rating and visual comfort probability method. Consequently, when the background contains areas of differing luminance, the background luminance of a glare source should be determined by the local background luminance affecting the local adaptation..
26. Position Index for a Glare Source in the Whole Visual Field.
27. Norio Igawa, Yasuko Koga, Tomoko Matsuzawa, Hiroshi Nakamura, Models of sky radiance distribution and sky luminance distribution, Solar Energy, 10.1016/j.solener.2004.04.016, 77, 2, 137-157, 2004.07, The aim of this research work is to propose sky radiance and luminance distribution models for all sky conditions from clear sky to overcast sky. The classification method of sky conditions is examined. Clear sky index is defined based on the global irradiance. Cloudless index is defined based on the global irradiance and the diffuse irradiance. The sky conditions are classified according to both indices. The data of the average sky radiance (luminance) distributions are obtained based on the classified sky conditions. The average relative sky radiance distributions are compared with the average relative sky luminance distributions. It has been confirmed that both radiance/luminance distributions can be shown by the same equation.An equation that shows the relative sky radiance (luminance) distribution for all sky conditions and equations that show the zenith radiance and the zenith luminance are obtained. The absolute value of the sky radiance (luminance) distribution is shown by multiplying the relative sky radiance (luminance) distribution and the zenith radiance (luminance). The equations to show the absolute values of the sky radiance distribution called the All Sky Model-R and the sky luminance distribution called the All Sky Model-L are proposed.Both models are compared with the previous models based on the measurement distributions concerning the region of sky vault and the sky conditions and good results are obtained. In addition, the vertical irradiance and illuminance calculated by the proposed models and the previous models are compared with the measurements, and the proposed models are confirmed their accuracy..
28. Norio Igawa, Yasuko Koga, Tomoko Matsuzawa, Hiroshi Nakamura, Model of Sky Radiance Distribution and Sky Luminance Distribution, Solar Energy, 77-2, pp.137-157, 2004.06.
29. The Sky Radiance and Luminance Distribution Estimated by Global Irradiance and Diffuse Irradiance.
30. Yasuko Koga, Ryusuke Tanaka, Daigo Shibata, Evaluation Structure on Night Streets: A case study in Fukuoka, The 25th CIE Session, Vol.2, pp.D542-D5545, 2003.06.
31. Yasuko Koga, Kazuhiko Kozakura, Yusuke Ogata, Evaluation of Non-uniform Luminous Environment by Image Analysis, The 25th Session of CIE, Vol.2, pp.D3170-D3173, 2003.06.
32. Glare Constant at Various Positions in the Visual Field.
33. Glare Constant at Various Positions in the Visual Field.
34. Norio Igawa, Hiroshi Nakamura, Tomoko Matsuzawa, Yasuko Koga, All Sky Model as a Standard Sky Luminance Distribution — Part 2 A Numerical Expression of Sky Luminance Distributions for All Sky Conditions —, Journal of Light and Visual Environment, 10.2150/jlve.27.16, 27, 1, 16-26, 2003, The aim of this research work is to establish a standard sky model for designing excellent daylighting schemes that cover all sky conditions from clear sky to overcast sky. In the previous paper (Part 1) 1), the “normalized global illuminance” was defined as a function of the measured global illuminance and the solar altitude for estimating the sky luminance distribution. In this paper (Part 2), the “Relative All Sky Model” is introduced. It offers formulas to show the relative sky luminance distribution as a function of the normalized global illuminance. The equation of the zenith luminance concerning the Relative All Sky Model is also a function of the normalized global illuminance. It is called the “All Sky Zenith Luminance” An absolute standard sky luminance distribution model called the “All Sky Model” is introduced that is a multiplication of the Relative All Sky Model and the All Sky Zenith Luminance. The All Sky Model can be calculated from the normalized global illuminance, i.e., from the measured global illuminance and the solar altitude or from the measured global illuminance, the horizontal diffuse illuminance, and the solar altitude. The global illuminance and horizontal diffuse illuminance are easily obtained from even the simplest daylight measurements.The All Sky Model can produce an excellent standard sky for daylighting design for any place where an advanced daylight environment is needed. KEYWORDS: sky luminance distribution, standard sky, daylighting design, All Sky Model..
35. A Numerical Equation of Sky Radiance Distribution for All Sky Conditions and the Estimation of Vertical Global Irradiances
A study on modeling sky radiance distribution Part 2.
36. Indices to Estimate Sky Radiance Distribution
A study on modeling sky radiance distribution Part 1.
37. Norio Igawa, Yasuko Koga, Tomoko Matsuzawa, Hiroshi Nakamura, Development of All Sky Model of Sky Radiance Distribution, Istanbul 2001 International Lighting Congress, Vol.II, pp.331-338, 2001.09.
38. All Sky Model as a Standard Sky Luminance Distribution
Part 2. Numerical expression of sky luminance distributions for all sky conditions.
39. All Sky Model as a Standard Sky Luminance Distribution
Part 1. Mueasurement and arrangement of data and parameters for a standard sky.
40. Prediction of Daylit Environment with Skylights: Daylighting calculation method with Mean Sky (Part 3).
41. Mathematical Expression of Mean Sky in Japan
Daylighting calculation method with Mean Sky (Part 1).
42. Yasuko Koga, Ken Anai, Hiroshi Nakamura, Cloud Amount and Daylight Availability, Balkan light '99, pp.124-129, 1999.10.
43. Tomoko Matuszawa, Yasuko Koga, Hiroshi Nakamura, Ken Anai, Daylight Illuminance by Cloud Type and Amount, CIE 24th Session, Warsaw, Vol.1, Part 2, pp.56-58, 1999.06.
44. Yasuko Koga, Ken Anai, Hiroshi Nakamura, Tomoko Matsuzawa, A Sky Scanner for Cloud Amount Measurement, CIE 24th Session, Warsaw, Vol.1, Part 2, pp.53-55, 1999.06.
45. Shin'ya Kojo, Hiroshi Nakamura, Yasuko Koga, Koichi Goto, Masahiro Shinozaki, A Basic Study on Standardization of the Sky Radiance Distribution, CIE 24th Session, Warsaw, Vol.1, Part 2, pp.50-52, 1999.06.
46. Ken Anai, Yasuko Koga, Hiroshi Nakamura, Koichi Goto, Masahiro Shinozaki, A Study on the Ratio of Sky Luminance to Sky Radiance, CIE 24th Session, Warsaw, Vol.1, Part 2, pp.20-22, 1999.06.
47. Dominique Dumortier, Yasuko Koga, Status of the International Daylight Measurement Programme (IDMP) and its Web Server (http://idmp.entpe.fr), CIE 24th Session, Warsaw, Vol.1, Part 1, pp.282-286, 1999.06.
48. Masahiro Shinozaki, Yasuko Koga, Hiroshi Nakamura, Sachiko Shimazaki, Shin'ya Kojo, Variations in Daylight during Solar Eclipses, CIE 24th Session, Warsaw, Vol.1, Part 1, pp.267-271, 1999.06.
49. Yasuko Koga, Hiroshi Nakamura, Kunio Matsuura, Daylighting Codes, Standards and Policies Mainly in Japan, Daylighting '98, pp.279-286, 1998.05.
50. Ryoko Kuroda, Hiroshi Nakamura, Yasuko Koga, Masahiro Shinozaki, Daylight Environment in Atria - Classification of forms of atria, LUX PACIFICA '97, pp.E79-E83, 1997.10.
51. Masaaki Okado, Hiroshi Nakamura, Yasuko Koga, Shun'ichi Fujii, Development of a New Artificial Sky, LUX PACIFICA '97, pp.E63-E66, 1997.10.
52. Ken Anai, Hiroshi Nakamura, Yasuko Koga, Masahiro Shinozaki, Daylighting Calculations for Skylights Based on the Mean Sky, LUX PACIFICA '97, pp.E52-E56, 1997.10.
53. Koichi Goto, Hiroshi Nakamura, Yasuko Koga, Norio Igawa, Shin'ya Kojo, Masahiro Shinozaki, Radiance Distributions of Clear Sky and Overcast Sky, LUX PACIFICA '97, pp.E46-E51, 1997.10.
54. Shin'ya Kojo, Hiroshi Nakamura, Yasuko Koga, Koichi Goto, Masahiro Shinozaki, Formulation of the Zenith Radiance and the Yearly Mean Sky Radiance, LUX PACIFICA '97, pp.E41-E45, 1997.10.
55. Yasuko Koga, Hiroshi Nakamura, Koichi Goto, Shin'ya Kojo, Jong-ho Seo, Distribution of the Relative Yearly Mean Sky Radiance, LUX PACIFICA '97, pp.E36-E40, 1997.10.
56. Norio Igawa, Hiroshi Nakamura, Tomoko Matsuzawa, Yasuko Koga, Koichi Goto, Shin'ya Kojo, Sky Luminance Distribution between Two CIE Standard Skies (Part 2), LUX PACIFICA '97, pp.E13-E18, 1997.10.
57. Tomoko Matsuzawa, Hiroshi Nakamura, Norio Igawa, Yasuko Koga, Koichi Goto, Shin'ya Kojo, Sky Luminance Distribution between Two CIE Standard Skies (Part 1), LUX PACIFICA '97, pp.E7-E12, 1997.10.
58. Masahiro Shinozaki, Hiroshi Nakamura, Yasuko Koga, Various Aspects of Flood Lighting in Kyushu, LUX PACIFICA '97, pp.D11-D16, 1997.10.
59. Shun'ichi Fujii, Hiroshi Nakamura, Kunio Matsuura, Yoshiaki Uetani, Yasuko Koga, Luminance Calculation Composed of the Luminous Flux Transfer Method, the Image Method and the Ray Tracing, LUX PACIFICA '97, pp.A17-A21, 1997.10.
60. Tomoko Matsuzawa, Hiroshi Nakamura, Yasuko Koga, New Reference Sky by Cloud Ratio for the Prediction of Momentary Daylit Environment, Proc. of Daylight Measurement and Application in Asia Pacific Region, 1997.01.
61. Yasuko Koga, Hiroshi Nakamura, Jong-ho Seo, Takashi Asai, Shin'ya Kojo, Automatic Clud Amount Measurement, 3rd SAAC Lighting Conference in Nepal, pp.146-152, 1996.11.
62. Ken Anai, Hiroshi Nakamura, Yasuko Koga, Koichi Goto, Formulation of the Mean Sky in Japan for Computer-based Daylighting Calculations, 3rd SAAC Lighting Conference in Nepal, pp.140-145, 1996.11.
63. Hiroshi Nakamura, Yasuko Koga, Activities of the International Daylight Measurement Programme (IDMP), CIE 23rd Session, New Delhi, 268-269, Vol.1, pp.268-269, 1995.11.
64. Jong-ho Seo, Hiroshi Nakamura, Yasuko Koga, Tomoko Matsuzawa, An Investigation on Sky Radiance, CIE 23rd Session, New Delhi, 250-251, Vol.1, pp.250-251, 1995.11.
65. Hiroshi Nakamura, Yasuko Koga, Ken Anai, Masaaki Okado, Koichi Goto, A Study on Dymanics of Daylit Environment in Living Spaces, CIE 23rd Session, New Dlhi, 244-245, Vol.1, pp.244-245, 1995.11.
66. Hiroshi Nakamura, Yasuko Koga, Norio Igawa, A Method for Classification of Sky Conditions, CIE 23rd Session, New Delhi, 242-243, Vol.1, pp.242-243, 1995.11.
67. Norio Igawa, Hiroshi Nakamura, Yasuko Koga, Classification Method of Measured Sky Luminance Distribution Data, CIE 23rd Session, New Delhi, Vol.1, pp.230-231, 1995.11.
68. Yasuko Koga, Hiroshi Nakamura, Satoshi Sata, Ken Anai, A Basic Study on Automatic Measurement of Cloud Cover, CIE 23rd Session, New Delhi, 196-199, Vol.1, pp.196-199, 1995.11.
69. Hiroshi Nakamura, Yasuko Koga, Norio Igawa, Development of Method for Classification of Sky Conditions - for the data gained by IDMP measurement stations, IES 39th Convention, Lights 94, pp.1-6, 1994.11.
70. In-jung Shin, Hiroshi Nakamura, Yasuko Koga, Koichi Goto, Analysis of Dynamic Aspect of Daylit Environment in Interiors, 2nd LUX PACIFICA, pp.C1-C6, 1993.11.
71. Tomoko Matsuzawa, Hiroshi Nakamura, Kunio Matsuura, Yasuko Koga, New Reference Sky for the Prediction of Momentary Daylit Environment, 2nd LUX PACIFICA, PP.C16-C21, 1993.11.
72. Jana Pulpitlova, Hiroshi Nakamaura, Yasuko Koga, Statistical Properties of Daylight Climate Data Derived from IDMP Continuous Measurements, 2nd LUX PACFICA, pp.C91-C96, 1993.11.
73. Nong Li, Hiroshi Nakamura, Yasuko Koga, Norio Igawa, Classification of Daylight and Solr Radiation Data into Three Categories by Sky COndition: overcast sky, 2nd LUX PACIFICA, pp.C10-C15, 1993.11.
74. Norio Igawa, Hiroshi Nakamura, Yasuko Koga, Tomoko Matsuzawa, New Automatic Controlled Instruments for Daylight Measurement of IDMP, 2nd LUX PACIFICA, pp.C97-C102, 1993.11.
75. Yasuko Koga, Hiroshi Nakamura, Muhammad Ramli Rahim, Daylight and Solar Radiation Data in Ujung Pandang, Indonesia, 2nd LUX PACIFICA, pp.C85-C90, 1993.11.
76. Muhammad Ramli Rahim, Hiroshi Nakamura, Yasuko Koga, Tomoko Matsuzawa, The Modified Equation on the Zenith Luminance of the Clear Sky, 2nd LUX PACIFICA, pp.C26-C31, 1993.11.
77. Tomoko Matsuzawa, Hiroshi Nakamura, Yasuko Koga, Muhammad Ramli Rahim, An Investigation on Cloud Ratio, LUX EUROPA 1993, pp.622-629, 1993.04.
78. Yasuko Koga, Hiroshi Nakamura, Masato Oki, Tomoko Matsuzawa, Muhammad Ramli Rahim, Study on Luminous Efficacy: The relation to cloud ratio, LUX EUROPA 1993, pp.799-803, 1993.04.
79. Hiroshi Nakamura, Yasuko Koga, Norio Igawa, Muhammad Ramli Rahim, Koichi Goto, Nong Li, Statistical Arrangement of the Data for IDMP in Japan, LUX EUROPA 1993, Vol.II, pp.518-531, 1993.04.
80. Yasuko Koga, Hiroshi Nakamura, Toru Otsuru, Prediction of Illuminance Distribution in Interiors under Skylights, CIE 22nd Session, Vol.1, Part 1, pp.120-121 (Division 3), 1991.07.
81. Hiroshi Nakamura, Masato Oki, Yasuko Koga, Research Class Measurement Stations for IDMY in Japan, CIE 22nd Session, Vol.1, Part 1, pp.116-117 (Division 3), 1991.07.
82. Hiroshi Nakamura, Masato Oki, Yasuko Koga, New Sky Scanner for the Measurement of Sky Luminance Distribution, CIE 22nd Session, Vol.1, Part 1, pp.61-62 (Division 3), 1991.04.
83. Hiroshi Nakamaura, Masato Oki, Yasuko Koga, Daylight and Solar Radiation Measurement Stations Newly Established in Japan, International Daylighting Conference, DAYLIGHTING '90, Session C-23, 1990.10.
84. Hiroshi Nakamura, Masato Oki, Toru Otsuru, Yasuko Koga, Mean Skies at Various Points in Europe, 6th LUX EUROPA, pp.262-271, 1989.10.