• KIEAE Journal
• /
• 제17권5호
• /
• pp.61-68
• /
• 2017

Purpose : Ando Tadao has his own unique architectural conception to reproduce natural view on site, and he continues to create new architecture without regarding to any principles. Ando Tadao experiments his imagination through the museum architecture, starts organization of space with light, and completes organization of space with light at once. Methods : The research works as follows: 1) Analyzes the meaningful characteristics showed in his architectural works. 2) Analyze organization of space and use of light in museums designed by Ando Tadao. 3) Selecte his representative museums in Korea and Japan, and then analyze space composition and light use through literature study and field survey. Result : The organization of museum space by Ando Tadao has a close relationship with the light. Light designed by Ando Tadao represents unique architectural varieties such as cushioning space, moving line, spatial characterization, and natural influx.

• KSBB Journal
• /
• 제6권2호
• /
• pp.189-194
• /
• 1991

The effect of wtlitc light on unaeraten growth of Baker's yeast and the accompanying ethanol production has been studied in a batch process at 27$^{\circ}C$. Over the 80-hour period of the Champagne yeast process without pH control, the cull growth was inhibited by the fluorescent light. Another observed difference between the runs is that the drop and subsequent rise in redox potential occurred much sooner in the fermentation with light than in the fermentation without light. This preliminary study indicated that ethanol production could be enhanced by light as the cell concentration is repressed. The possible pathway, shift of the sugar substrate toward ethanol and away from cells was manifested by another difference as well. As observed under the microscope, many of the yeast cells grown under light budded without dividing by the normal fission process as they did in the dark. Furthermore, the undivided and branched (light grown) cell did not agglutinate at the end of the fermentation process as did the distinct spherical (dark grown) cells.

• 한국윤활학회:학술대회논문집
• /
• 한국윤활학회 2001년도 제33회 춘계학술대회 개최
• /
• pp.287-298
• /
• 2001

Change in light transmission characteristics caused by various types of oil contaminations was experimentally measured with a built-in type wear monitoring device. Three kinds of iron powders of different size distribution, carbon dust, two kinds of solutions and grease were used for the lest contaminants in this work. Light intensity of the transmitted light was treasured with the contamination level. Results showed that the transmitted light intensity decreased linearly with the contamination concentration in the oil and the slope was affected by the size distribution. Light attenuation was also caused greatly by carbon dust, water contamination and polymeric fibers mainly due to the light absorption. As a result, it was proved that the optical measurement device could be applicable effectively for detecting any significant change iii lubricating oils.

• Journal of information and communication convergence engineering
• /
• 제19권4호
• /
• pp.269-275
• /
• 2021

Light-emitting diodes (LEDs) are modulated using a square wave pulse sequence for flicker prevention and dimming control in visible light communication (VLC). In a VLC transmitter, the high and low bits of the non-return-to-zero (NRZ) data are converted to two square waves of different frequencies, which continue for a finite time defined by the fill ratio in an NRZ bit time. As the average optical power was kept constant and independent of data transmission, the LED was flicker-free. Dimming control is carried out by changing the fill ratio of the square wave in the NRZ bit time. In the experiments, the illumination of the LED light was controlled in the range of approximately 19.2% to 96.2% of the continuous square wave modulated LED light. In the VLC receiver, a high-pass filter combined with a latch circuit was used to recover the transmitted signal while preventing noise interference from adjacent lighting lamps.

• 한국멀티미디어학회논문지
• /
• 제21권11호
• /
• pp.1244-1253
• /
• 2018

The color of traffic light is sensitive to various illumination conditions. Especially it loses the hue information when oversaturation happens on the lighting area. This paper proposes a traffic light recognition method robust to these illumination variations. The method consists of two steps of traffic light detection and recognition. It just uses the intensity and saturation in the first step of traffic light detection. It delays the use of hue information until it reaches to the second step of recognizing the signal of traffic light. We utilized a deep learning technique in the second step. We designed a deep convolutional neural network(DCNN) which is composed of three convolutional networks and two fully connected networks. 12 video clips were used to evaluate the performance of the proposed method. Experimental results show the performance of traffic light detection reporting the precision of 93.9%, the recall of 91.6%, and the recognition accuracy of 89.4%. Considering that the maximum distance between the camera and traffic lights is 70m, the results shows that the proposed method is effective.

• International Journal of Advanced Culture Technology
• /
• 제9권4호
• /
• pp.315-319
• /
• 2021

Recent impact of 4th industrial revolution is increasing usage of IoT technology along with smartphones and tablet PC. However blue light emitted from electronic devices such as smartphones and tablet PC causes detrimental change to human bodies. As the controversy over the harmfulness of blue light became known through the media and various communities, related markets were formed, and various blocking films, software, and vision protection monitors were released. In this paper focuses on utilizing IoT technology to protect human organizations from blue light. It presents anti-blue light system which prevents excessive exposure to blue light through Arduino module such as ultrasound, piezo buzzer and blue light measurement module.

• Fisheries and Aquatic Sciences
• /
• 제26권8호
• /
• pp.514-523
• /
• 2023

The visible threshold of Oreochromis niloticus responded to high light intensity under short wavelengths, whereas the response to low light intensity under long wavelengths was low, with a minimum visual threshold of 574 nm of LED lights. Movement distance of O. niloticus was dropped at 31℃ and increased abnormally at 37℃ under natural light. Comparing movement distance under red (622 nm) and green (518 nm) lights of LED, movement distance and swimming speed under red and green lights were higher than under natural light. However, the movement distance decreased rapidly at 31℃ under red light and lowest at 33℃ under green light. After that, there was a tendency to adapt to high water temperatures gradually. Consequently, red and green lights may be recommended for O. niloticus's aquaculture because the red and green lights have a positive effect on growth performance, survival rate, and metabolism, as shown in previous studies. It is necessary to control the water temperature below 32℃ because abnormal behavior above 32℃ revealed under red and green LED lights and natural light.

• 한국정밀공학회지
• /
• 제11권6호
• /
• pp.168-178
• /
• 1994

This paper presents an optical surface roughness sensor developed for intermediate- process measurement on the machine. The light scattering method is adopted for the sensor, which is designed conpact and flexible enough to apply to 'on the machine' measurement of surface roughness. The developed sensor has special features such that it makes use, as the measurement parameter, of the ratio between fluxes of the incident light, and the specularly and partly diffusely reflected light, and that it can adjust the incident light angle. The experimental investigation reveals not only the sensor has good performance as a surface roughness sensor but the sensor is very robust so as to be useful in in-process measurement.

• 천문학회보
• /
• 제46권2호
• /
• pp.61.1-61.1
• /
• 2021

Squeezed light는 중력파 검출기의 양자 잡음을 줄여 측정의 민감도를 향상시키기 위해 사용하는 양자 광원이다. Squeezed light는 광학적 손실에 민감하기 때문에 중력파를 측정하기 위해서는 정밀한 mode matching이 필요하다. 하지만 mode mismatching은 실제 실험 상황에서 동적으로, 그리고 무작위로 나타나므로 정밀하게 조정하기 어렵다. Mode mismatching에 견고한 squeezed light를 만들기 위해서는 multimode squeezed light가 필요하다. Multimode squeezed light를 만드는 방법으로 는 self-imaging cavity를 이용하여 생성하는 방법이 대표적으로 알려져 있다. 이 발표에서는 self-imaging cavity 기반으로 만든 optical parametric oscillator(OPO) 에서 생성된 squeezed light가 기존 OPO로 생성한 squeezed light 보다 여러 spatial mode mismatching (위치, 방향, 크기 빗맞음)에 대해 견고함을 소개한다.

• International Journal of Advanced Culture Technology
• /
• 제12권2호
• /
• pp.353-359
• /
• 2024

The color temperature and light color of nighttime lighting in a particular city is an important factor in determining its nighttime identity. To quantitatively analyze the nocturnal characteristics of Seoul, this study focuses on the light color of the lighting sources that used in the places included in the Seoul Night View 100 Photobook. As a result, the color temperature of white light in the surveyed places is in the range of 2,500~3,500K, of which 3,000~3,500K represents the highest proportion. In addition, the color temperature in the 2,500~3,500K range was found to be evenly distributed across the five surveyed regions. Apart from white light, blue color hue accounts for a high percentage in the monochromic light category, and the excitation purity was measured to be 71.6% on average. In addition, 46% of the buildings with monochromic light are in urban centers.