• Journal of Astronomy and Space Sciences
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• v.17 no.2
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• pp.173-180
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• 2000

All times of minimum light of V651 Cas, which is still less studied so far, were analyzed. From our analysis, it was found that the orbital period of the system may have varied in a periodic manner. After assuming that the period change is produced by the light-time effect due to a third body in the system, attempts to derive the orbital elements of the light-time orbit were made. The resultant values for the period, semi-amplitude, and eccentricity of the light-time orbit were 6.${y}^{25}$, 0.${d}^{0013}$, and 0.77, respectively. The future observations of times of minimum light of V651 Cas are needed to confirm the existence of the third body we suggested in this paper.

• Korean Institute of Interior Design Journal
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• v.16 no.2 s.61
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• pp.339-346
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• 2007

This thesis has purpose of explaining that light is not only appreciated but also physically percepted in contemporary space design and examining effects of space experience through the physical perception. In keeping with such developments, light has been perceived as the object of another architectural tool in modern space design and has provided men with new experience by providing space image and function different from previous ones. With the expansion of the area of light, light has changed a space that is not a simple architectural factor into the essential concept that gives the architectural space image ! by combining it with architectural space, structure, form and materials throughout the whole process from the beginning to the completion. Through phenomenological approach, light is percepted and experienced by body movement, intervention of senses and memories, and passing of time. The percepted and experienced light brings increase of mutual understanding in space, activation and continuance of user's sensation, recreational experience by event occurrence and space experience effect thorough information from media.

• Current Applied Physics
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• v.18 no.12
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• pp.1600-1604
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• 2018

This paper reports on a systematic and quantitative assessment of light induced degradation (LID) and regeneration in full Al-BSF and passivated emitter rear contact cells (PERC) along with the fundamental understanding of the difference between the two. After LID, PERC cells showed a much greater loss in cell efficiency than full Al-BSF cells (~0.9% vs ~0.6%) because the degradation in bulk lifetime also erodes the benefit of superior BSRV in PERC cells. Three main regeneration conditions involving the combination of heat and light ($75^{\circ}C/1\;Sun/48h$, $130^{\circ}C/2\;Suns/1.5h$ and $200^{\circ}C/3\;Suns/30s$) were implemented to eliminate LID loss due to BO defects. Low temperature/long time ($75^{\circ}C/48h$) and high temperature/short time ($200^{\circ}C/30s$) regeneration process was unable to reach 100% stabilization. The intermediate temperature/time ($130^{\circ}C/1.5h$) generation achieved nearly full recovery and stabilization (over 99%) for both full Al-BSF and PERC cells. We discussed the effect of temperature, time and suns in regeneration mechanism for two cells.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.3
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• pp.491-498
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• 2005

Occlusal fissures and pits are ideal places for the development of caries. Pit and fissure sealants are now considered as a very effective means to prevent dental caries. The purpose of this investigation was to examine the effect on the sealant penetration of the elapse of time from the application of sealant until exposure to visible light, and to examine the effect of the filler content and tooth position on the sealant penetration. 192 extracted human premolars were used to this experiment. Following enamel conditioning, a light-polymerized sealant was applied and 4 different periods of time(3, 5, 10, 20 seconds) were allowed until exposure to the light source. The results obtained were as follows; 1. According to time, in both unfilled sealant and filled sealant penetration increases deeply through mindfulness. 2. Sealant that apply to mandiblar premolar penetrated deeply through than to maxillay teeth. 3. Penetration difference according to filler content, unfilled sealant penetrated deeply through than filled sealant. The result from this study indicated that unfilled sealant penetrated most deeply in mandible when at least 20s time elapsed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.358-361
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• 2004

The photocatalytic degradation of Endocrine Discruptors, dibuthyl phthalate(DBP) has been investigated over TiO$_2$ photocatalysts irradiated with a ultraviolet (UV) light. The effect of operational parameters, i.e., reaction time, light intensity, pH and additive on the degradation rate of aqueous solution of Endocrine Discruptors has been examined. Results show that the employment of efficient photocatalysts and the selection of optimal operational parameters may lead to degradation of Endocrine Discruptors solutions.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.248-251
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• 2013

The purpose of this study was to investigate the inactivation effect of intense pulsed light (IPL) on Micrococcus roseus, an irradiation-resistant bacterium isolated from laver, and the commercial feasibility of this sterilization method on dried laver. The inactivation of M. roseus in cultivated plates increased with increasing light intensity and treatment time. Approximately 6.6 log CFU/mL reduction of the cell viability was achieved with IPL treatment for 3 min at 1,000 V of light intensity, tailing was not shown. In addition, the inactivation rate of M. roseus increased with increasing pulse number at same light intensity and treatment time. The killing efficiency for M. roseus increased with by decreasing the distance between the light source and the sample surface.

• 보존과학연구
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• s.17
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• pp.123-160
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• 1996

There have been many studies and experiments regarding exhibition lighting. Many experiments on photochemical damaging effect and visibility resulted in a practice limited to assigning light levels and adjusting annual exposure time. The three damaging factors to the artifacts are intrinsicsusceptibility to absorb radiant energy, spectral distribution of light source and intensity of illumination and time of exposure. Dividing all the artfacts into three categories to suggest a recommended illuminance level causes some problems. Blue wool, for example, used as the reference material for susceptibility, is not a standard material representing museum artifacts. In the most light sensitive category, ISO class I or anything below have been excluded. The exposure time of one soure can be three times more than another sourece. The spectral distribution of the light source and the relative spectral responsibility of the artifact are not considered in the practice. So in case of very light sensitive material, the recommended illuminance is only the referring value and it is indispensable to check the characteristic of susceptibility of each artifacts. Daylighting is prevailing method to solve the psychological need of the visitors. However, it sould transparent, and should not diffused, and the green-house effect must be considered. llluminance uniformity should based on the maximum illuminance to handle the limitation of exposure for the conservation of a large sensitive object such as a painting. Damage index is not absolute reference for selecting the lighting source because it is experimented from the paper of low grade then calculated. Visibility should be increased by reducing the visual noiseand by planning of appropriate luminance contrast. This paper reviews the problems with the previous studies and experiment sand the current exhibition lighting design practice. The plan for museum showcase lighting is to check the susceptibility and to raise the visibility simultaneously.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.3
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• pp.9-20
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• 2016

This study compared the effect of green light consequent on maximum brightness 85 lx and intial brightness 15 lx, and its accompanying psychological, physiological response. 1) As a result of psychology(general stress evaluation, Symptom Checklist-90-Revision) evaluation, all stress evaluation items mostly showed a decrease, and they are comparatively positively evaluated in minimum brightness 15 lx comparing to maximum brightness 85 lx. 2) Physiological (Heart Rate Variability) evaluation result was included in stable range in all cardiovascular system variables after light stimulus in time of comparison with the standard range; in addition, the Heart Rate Variability evaluation result was found to be stable in all cardiovascular system variables except Low Frequency in minimum brightness 15 lx comparing to maximum brightness 85 lx. 3) Green light was found not to appear as a stimulating factor in the human body in time of space projection, being found to be effective in stability of mind and body, and reduction in stress. Thus, it was found that green light functioned as an emotional, relaxing tranquilizer by working on the sympathetic nervous system.

• The Research Journal of the Costume Culture
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• v.28 no.6
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• pp.875-889
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• 2020

This study examined the effect of Instagram usage time (short, long) and spending on fashion products (light, heavy) on product attitude and purchase intention of products promoted by an influencer. The moderating effect of influencer type (mega, macro, micro) was also investigated. A total of 515 males and females in their 20s participated in an online survey. Descriptive statistics were analyzed and exploratory factor analysis and two-way ANOVA were conducted. Research findings were as follows. First, the usage time, both short and long, had a positive effect on product attitude. Also, the interactive effects of usage time and influencer type on product attitude were found. Consumers with short Instagram usage time displayed the highest attitude toward products promoted by a macro-influencer whereas consumers with long Instagram usage time displayed the highest attitude toward products promoted by a micro-influencer. Second, usage time and influencer type did not show interactive effects on purchase intention. Third, both categoriacl variables of users' spending on fashion products had a positive effect on product attitude. Fourth, the interaction effects of spending on fashion products and influencer types on purchase intention were found. The group of light buyers showed the highest purchase intention on products promoted by the macro-influencer while the group of heavy buyers showed the highest purchase intention of products promoted by the micro-influencer. Based on the results, implications were suggested.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.8
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• pp.760-765
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• 2008

Low power laser therapy is internationally certified and is known to be effective in stimulating DNA in living organisms, increasing protein synthesis and activating cell division, smoothing blood circulation, promoting cell activation, cell regeneration and function. It also has anti-inflammatory, anti-edemic, anti-fibrous dysplastic and neuralogic hyperfunctional effects. This study was intended to verify the effect of LED irradiation therapy on wound healing in cell and animal tests by applying LED irradiator using a laser and laser diode, which was independently designed and developed to emit beams of similar wavelength to that of a laser. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity and reservation. In case of cell proliferation experiment, each experiment was performed to irradiation group and non-irradiation group for tissue cells. MTT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590 nm transmittance of micro-plate reader. In the wound healing experiment, 1$cm^2$ wounds on the skin wound of SD-Rat(Sprague-Dawley Rat) were made. Light irradiation group and none light irradiation group divided, each group was irradiated one hour a day for 9 days. As a result, the cell increase of tissue cells was verified in irradiation group as compared to non-irradiation group. And, compared with none light irradiation group, the lower incidence of inflammation and faster recovery was shown in light irradiation group.