• Journal of Korean Ophthalmic Optics Society
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• v.18 no.3
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• pp.297-304
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• 2013

Purpose: To investigate blue light rejection and the percentage of blue light in the visible light of blue light blocking lens according to light source, and to study prescriptions for blue light blocking lens Methods: UV-VIS spectrophotometer was used for blue light rejection and the percentage of blue light in the visible light according to light source, and the percentage of blue light in solar light was used to evaluate the prescription for blue light blocking lens. Results: The blue light rejection and the percentage of blue light in the visible light of each lens were depending on light sources. Through the way to compare the percentages of blue light in the visible light passing through the lens with that in solar light, blue light blocking lenses suitable to each light source could been selected. Conclusions: In the prescription for blue light blocking lens, inquiry for user's display must be preceded. And then the percentages of blue light in the visible light passing through the lens based on that in solar light may be useful as a method of evaluating the prescription for blue light blocking lens.

• Journal of the Korea Convergence Society
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• v.12 no.7
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• pp.61-67
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• 2021

The purpose of this study was to investigate the colors of spectacle lenses that would be effective in blocking blue light among various colors so that the damage caused by blue light could be conveniently reduced even in daily life and when filling with dental light-curing resin. Each color dye of orange, brown, gray, yellow, red, and rosa was dissolved in an individual container of a spectacle lens tinting machine, and 6 uncolored spectacle lenses were immersed in a temperature of 90℃ for 1 hour to color. As a result of comparing the blue light transmittance of the colored spectacle lens and the tip for the photopolymerizer, the blue light transmittance of the orange colored lens was 0.82%, and the blue light blocking effssect was the best. Brown and gray tinted lenses had excellent blue light blocking rate, but it was difficult to recognize objects through the lens due to the high tinted concentration, and yellow tinted lenses were found to be effective when the tint was similar to the tip. The blue tinted lens had a blue light transmittance of 15.10%, which was lower than other tinted lenses. The results of the experimental study are expected to be helpful in recognizing the blue light transmittance by spectacle tinted lenses of various colors and making efforts to select the appropriate blue light blocking lens color and block harmful blue light stimuli.

• The Korean Journal of Vision Science
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• v.20 no.4
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• pp.413-420
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• 2018

Purpose : We present a novel method for the analysis of blue light applied by the analysis method of David L. with optical experiment and blue light by measuring the transmittance by dividing it by the refractive power in the spectacle lens made by MR8. Methods : The lenses of -8.00D, -7.00D, -6.00D, -5.00D, -4.00D, -3.00D, and 0.00D manufactured by MR8 being sold in the market, were selected. The transmittance was measured at the intervals of 5 nm from 200 to 1000 nm with UV-VIS Spectrophotometers (SolidSpec 3700), and they were in range of the blue light (380 to 500 nm) analyzed by a David L.'s analysis method. Results : All of the MR8 lenses selected for this study almost completely blocked at the UV range. A lens of -8.00D was measured as the lowest transmittance of 59.56% in the blue light area and low values were measured at the blue areas 1 and 2 according to the analysis of David L.In the infrared ray area, the transmittance of all lenses gradually decreased. The average value of the luminous transmittance was 23.67% ~ 26.33% and then gradually decreased from -4.00D. Conclusion : Applying the analysis of David L., a minimum of 41.28% and a maximum of 46.60% were measured at the blue light 1 area and a minimum of 87.30% and a maximum of 97.55% were measured at the blue light 2 area. A minimum of 86.83% and a maximum of 96.55% were measured at the blue light 3 area, and the average was 94%. The luminous transmittance of the -3.00D lens was 26.33%, which was the highest, and that -8.00D was 23.67%, which was the lowest.

• Journal of the Korea Convergence Society
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• v.12 no.7
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• pp.125-131
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• 2021

Blue light with strong energy is required for light-curing resin treatment, which is being used more frequently in dentistry. To reduce the risk of exposure to scattered light, we tried to use colored lenses. The tips for light curing machine and a commercially available yellow-type blue-light blocking lens and a yellow lens colored with yellow dye, which are expected to be effective in blocking blue light, were placed in a UV-Vis spectrometer device, and transmission and blocking of blue light were tested respectively. As a result, the average blue light blocking rate of the light curing machine tips was 99.49%, and the C lens with the highest color density among commercially available lenses showed a high blue light blocking rate of 99.54%. In the case of lenses tinted with yellow, the yellow tinted C lens with the highest tint concentration showed 87.57% of blue light blocking rate. It is judged that the side effects related to the eyes caused by blue light can be reduced if a yellow-type commercially available or colored lens is worn along with a light curing machine tip during resin treatment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.312-319
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• 2017

For high value-added applications of natural blue diatomite, the physical refining process and synthesis of SiC from refined diatomite were investigated. Approximately 30 percent Fe ($Fe_2O_3$) in raw blue diatomite was removed by a particle sieve separation process; the Fe composition for 325 mesh down powder was approximately 2 percent. Although a wet and/or dry magnetic separation process had some influence on the separation and/or refining of Fe composition, the Fe composition in the non-magnetic by-product was approximately 2 percent. Water leaching separation was effective in removing the Fe composition; approximately 40 percent of the Fe in raw blue diatomite was removed. The synthesis of ${\beta}$-SiC by a carbothermal reduction of the $SiO_2$ in the refined diatomite using carbon (graphite, carbon black), the effects of an acid-treatment on removing the Fe, and the specific surface area for the synthesized powder were also investigated. The impurities were mostly eliminated and the specific surface area was increased to $52.5m^2/g$.

• Journal of the Korea Convergence Society
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• v.10 no.12
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• pp.177-181
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• 2019

The purpose of this study was to investigate the degree of blocking of blue light of the tips and goggles of the curing light during the dental treatment using the blue light of the light curing. The light curing tips and goggles were placed on a UV-Vis spectrometer and the results of light transmission were analyzed. Comparative analysis. As a result, all four types of light curing tips used in the analysis showed excellent blue light blocking effect. In the case of safety goggles, red-type goggles showed blue light transmittance similar to those of light curing than yellow-type goggles. As a result, it is recommended that the attachment of the light curing with high degree of blue light blocking and the wearing of safety glasses are necessary to protect the eyes. This behavior is thought to reduce persistent irritation and fatigue in the eyes.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.165-169
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• 2000

Life cycle of Tropidothorax cruciger(Motschulsky) was studied on Cynanchum wilfordii Hemsley in the field as well as its development, overwintering patterns, and host preferences. Overwintered adults appeared in early and mid May, and the first generation adults emerged from late June extending to mid August. Second generation adults which usually overwinter, appeared from mid September to early October and were usually found beneath the soil surface or fallen leaves in winter. Adults were not attracted to various light sources. T. cruciger showed host preferences specifically toward Metapiexis japonica and Cynanchum wilfordii, both in the family of Asclepiadaceae.

• Journal of the Daesoon Academy of Sciences
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• v.35
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• pp.331-358
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• 2020

This paper is a study of Kim Si-seup's maniacal tendency. The properties of mania can be divided into two categories. One is mental mania wherein the mind has fallen into madness, and the other is morphological mania wherein madness is revealed in real world actions. This thesis analyzes two aspects of the madness of Kim Si-seup, who showed madness in the morphological dimension as well as madness of the mind in the Joseon Dynasty. One notion that is analyzed is 'Longing to never return', and the other is 'To live in obscurity, yet practice wonders.' Kim Si-seup was a promising talent when he was young and was a so-called "infant prodigy." However, when 'Saejo' took the throne of 'Danjong,' he left the house on the road to 'burn all the books' and became a monk as a way of disappearing from the world. Thereafter, Kim Si-seup gave up on the test to become a bureaucrat and lived in hiding while doing strange things while he falsely pretended to be "crazy." He never felt regret hearing others describe him as a strange person. He lived a life of not returning to the mundane world for a long time as he traveled through famous mountains and streams. Also, he pursued a life in 'the world outside the world' without any greed. Sometimes he expresses his own free spirit and madness through poetry with 'what he talks about' and 'wonderful words.' This life was far from a form of neutralization aesthetics achieved by pursuing a 'gentle and magnanimous' life as claimed by Confucian scholars. Kim Si-seup, sometimes referred to as 'a maniac with mental clarity,' directed his efforts at 'false maniacal behavior,' 'weird behavior,' 'life pursuing the world outside the world,' and 'life of breaking off one's relationship with the world.' This maniac-like life of Kim Si-seup was not crazy but conveyed a deep desire to criticize the absurd reality of Joseon society at the time. Regarding Kim Si-seup, Li Hwang criticizes him for wishing 'to live in obscurity yet practice wonders.' Unlike Li Hwang, Yi Yi, who wrote The Records of Kim Si-seup when commissioned to do so by Sun Jo, positively evaluated Kim Si-seup as "a Confucian who followed Buddhism." Although the contents of these evaluations of Kim Si-seup were different, both agreed that Kim Si-seup was a maniacally-oriented individual. Kim Si-seup, who was mentally maniacal and morphological maniacal, represents a unique case in the study history of the Joseon Dynasty, wherein the 'the doctrines of Zhu Zi' exerted great influence.