• Journal of The Korean Digital Architecture Interior Association
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• v.5 no.1
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• pp.9-16
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• 2005

In Interior design, light is the most important factor in deciding color, texture and illumination level which are the basic factors of spatial design. To apply rendering technologies on prediction of illuminating effect, it is important to understand and analyse the basic properties of the illumination models that are local illumination model and global illumination model. The illumination models in computer graphics express the factors which determine the surface color, texture and light distribution through the reflection. The purpose of this study is to propose the best way of shading algorithm in interior space provided by the computer, based on the experimental analysis that 5 shading methods are applied to the interior space. The results of this study were as followed. 1) Local illumination models that are Lambert shading, Ground shading and Phong shading are not suitable to the prediction of interior illumination effect. 2) Ray tracing that is global illumination model could be adopted to interior illumination effects. Ray tracing is a very versatile algorithm because of the large range of lighting effects it can model. 3) Neither radiality nor ray tracing offers a complete solution for simulating all interior illumination effects. 4) Radiosity excels at rendering diffuse-to-diffuse inter-reflections and ray tracing excels at rendering specular reflections. By merging both shading techniques, that offers the best of both. Using computer technologies to simulate lighting in preliminary design stage which will provide information for designers and occupants to determine the effect of using artificial light sources at each stage of their design process. Further study in illumination analysis, prediction of illumination effect, and lighting calculation is required as computer media expands.

• Journal of the Korean Home Economics Association
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• v.35 no.4
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• pp.149-158
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• 1997

The purpose of this study is to investigate the actual conditions of illumination circumstances in living rooms and the evaluation of residents about those. The respondents of this study were residents of 236 detached houses and 163 apartment houses in Taegu city, The results are as follows: (1) Fluorescent lamps are usded in living rooms by half and plural lighting fixtures are generally used; ceiling light and chandelier. While direct light system is generally used and core type is the most frequent in living rooms. (2) The average used illumination level is 59.7 1x while the possession illumination level is 84.9 1x by investigating of illumination circumstances. (3) Over half of residents are satisfied with illumination circumstances in their own houses. While they wish to improve the lighting fixtures lightness and the kind of light soure in order. And the evaluation of residents are medial level.

• Journal of Biosystems Engineering
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• v.25 no.1
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• pp.25-32
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• 2000

Motivated by the need for developing the more efficient lighting system for light culture in the greenhouses, this paper aims to predict the illumination of incandescent lamp according to various levels of lighting and various kinds of the lamp. The results obtained in this experiment are summarized as follows. 1. The general equation to predict the illumination according to the kind of incandescent lamp and the installation height was suggested as {{{{y= { a + bx+ cx^2} over { 1+dx+ex^2~ + fx^3} [lx]}}}} , where , a, b, c , d, e and of were arbitrary constants. 2. Maximum illumination of hat-covered lamp of 60 W was 1.2 -1.5 times as many as uncovered lamp. 3. Maximum illumination of yellow color painted lamp of 100 W was 1.3 times as many as unpainted lamp.

• Journal of Sensor Science and Technology
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• v.25 no.5
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• pp.303-309
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• 2016

In this paper, we introduce a new method for controlling the illumination of LEDs in visible light communication (VLC) by changing the duty cycle of Manchester code. When VLC data were transmitted in Manchester code, the average optical power of the LEDs was proportional to the duty cycle. In experiments, we controlled the illumination of a $3{\times}3$ LED array from 10% to 90% of its peak value by changing the duty cycle of the Manchester code. The synchronizing clocks required for encoding and decoding the Manchester code were supplied by pulse generators that were connected to a 220 V power line. All pulse generators made the same pulses with a repetition frequency of 120 Hz, and they were synchronized with the full-wave rectified voltage of the power line. This scheme is a very simple and useful method for constructing indoor wireless sensor networks using LED light.

• Journal of Sensor Science and Technology
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• v.30 no.4
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• pp.196-203
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• 2021

In this study, an optical identification system was developed, wherein visible light is used to transmit the interrogating signal, and infrared is used to send the response signal. In the reader, visible light from a light emitting diode (LED) array was modulated via modified pulse width modulation for flicker-free illumination and dimming control. Moreover, the duty factor of the dimming control time was employed to control the illumination from the LED. In the transponder, the spike signal in the output of the high-pass filter was utilized to recover the interrogating signal while preventing interference from the 120-Hz noise from adjacent lighting lamps. The illumination was controlled in 26-86% range of the constant wave LED illumination by changing the duty factor from 20% to 90%. This configuration is advantageous for the construction of optical identification systems for automatic security check and car fare calculation at toll gates or parking facilities.

• Korean Journal of Plant Resources
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• v.25 no.6
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• pp.731-738
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• 2012

Dandelion has been widely utilized for medicinal and edible purposes. This research was conducted to evaluate the effect of supplemental LED (light-emitting diode) light on germination, growth characteristics and anthocyanin content of dandelion (Taraxacum officinale) seedling using LED blue (460 nm), red (660 nm, R), blue + red (B:R=6:4) and fluorescent lamp light treatment. By LED illumination to T. officinale seed germination speed was delayed, and germination rate was the highest in the fluorescent light. The growth characteristics (plant height, number of leaves, root length and fresh weight) were greatly influenced by supplemental LED light compared with control treatment, and the growth promotion was the most effective in the red LED illumination. After 60 days of red and mixed LED light treatments, anthocyanin content of dandelion plants was significantly changed. The anthocyanin content was increased by 12~19 mg/100 g under the red LED and the mixed light conditions compared with the control and the blue LED. Results indicate that illumination with red and mix LEDs, compared with other light treatments, is beneficial for promotion of growth and anthocyanin content in dandelion.

• Journal of the Speleological Society of Korea
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• no.85
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• pp.1-14
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• 2008

Electroluminescent Display(ELD) will be the innovative ideas to replace existed electricity illumination systems that consider to under effectiveness and environmental pollution generators in the commercial caves because ELD has less heat and low electricity consumption by the new illumination materials. Characteristics of the ELD are as following: it is a proper matter for the small merchandise ads due to its thickness is only below 3oo micoron, electricity consumption of ELD is less (1/3) than LED, ELD that is a whole face illumination system is much brighter than LED that is a dot illumination system, ELD is longer life than others due to its less light generation systems, ELD is any problems to bend, and it is a best device to use a light board ads. ELD has advantages on conservation of cave biosystems and reduce pollution when ELD is installed in touring spots and emergency corridors of weak illuminated cave internal areas by less heating and low electricity consumption using the indirect illumination of the ELD. Therefore when the high technologic ELD is installed in the commercial caves in Korea, it will be innovating cave environmental systems, saving budgets, and increasing tours.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.7
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• pp.697-700
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• 2004

We propose a method that realizes the modified illumination by implementing a binary phase grating at the backside of a photomask. By modeling the relationship between the shape of a grating on the photomask and the light intensity at the pupil plane, we developed a program named MIDAS that finds the optimum grating pattern with a stochastic approach. After applying the program to several examples, we found that the program finds the grating pattern for the modified illumination that we want. By applying the grating at the backside of a photomask, the light efficiency of modified illumination may be improved.

• Korean Journal of Optics and Photonics
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• v.31 no.4
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• pp.183-190
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• 2020

In this paper, the illuminating optics of asymmetric light distribution was studied, which allowed the light distribution to be uniform even for short-range irradiation on a wide illumination area. In the case of a light installed at a short distance, the light is not diffused enough because of the short irradiation distance. For this reason, it is difficult to satisfy uniformity of illumination. In addition, lighting design for asymmetric distribution is required because the lighting device is installed tilted, for visibility. Therefore, the design of lighting systems with asymmetric light distribution could achieve uniform illumination of the target surface even under short-distance irradiation. This was then applied to the license lamp, a lighting system featuring short light irradiation distance, to confirm that it satisfies the legal standards.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.12
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• pp.122-130
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• 2010

This paper presents an active ranging system based on laser structured-light image. The structured-light image processing is computationally efficient in comparison with the conventional stereo image processing, since the burdensome correspondence problem is avoidable. In order to achieve robustness against environmental illumination noise, an efficient image processing algorithm, i.e., integration of difference images with structured-light modulation is proposed. Distance equation from the measured structured light pixel distance and system parameter calibration are addressed in this paper. Experiments and analysis are carried out to verify performance of the proposed ranging system.