• Journal of Environmental Science International
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• v.15 no.9
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• pp.855-864
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• 2006

This study introduces a method to eliminate formaldehyde and benzene, toluene from indoor air by means of a photocatalytic oxidation reaction. In the method introduced, for the good performance of the reaction, the effect and interactions of the $TiO_2$ catalyst and ultraviolet in photocatalytic degradation on the reaction area, dosages of catalysts, humidity and light should be precisely examined and controled. Experiments has been carried out under various intensities of UV light and initial concentrations of formaldehyde, benzene and toluene to investigate the removal efficiency of the pollutants. Reactors in the experiments consist of an annular type Pyrex glass flow reactor and an 11W germicidal lamp. Results of the experiments showed reduction of formaldehyde, benzene and toluene in ultraviolet $/TiO_2/$ activated carbon processes (photooxidation-photocatalytic oxidation-adsorption processes), from 98% to 90%, from 98% to 93% and from 99% to 97% respectively. Form the results we can get a conclusion that a ultraviolet/Tio2/activated carbon system used in the method introduced is a powerful one for th treatment of formaldehyde, benzene and toluene of indoor spaces.

• International Journal of Railway
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• v.1 no.3
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• pp.113-116
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• 2008

The long-tenn exposure of polymeric composite materials to extreme-use environments, such as pressure, temperature, moisture, and load cycles, results in changes in the original properties of the material. In this study, the effect of combined environmental factors such as ultraviolet ray, high temperature and high moisture on mechanical and thermal analysis properties of glass fabric and phenolic composites are evaluated through a 2.5 KW accelerated environmental aging tester. The environmental factors such as temperature, moisture and ultraviolet ray applied of specimens. A xenon-arc lamp is utilized for ultraviolet light and exposure time of up to 3000 hours are applied. Several types of specimens - tensile, bending, and shear specimens that are warp direction and fill direction are used to investigate the effects of environmental factors on mechanical properties of the composites. Mechanical degradations for tensile, bending and shear properties are evaluated through a Universal Testing Machine (UTM). Also, storage shear modulus, loss shear modulus and tan a are measured as a function of exposure time through a Dynamic Mechanical Analyzer (DMA). From the experimental results, changes in material properties of glass fabric and phenolic composites are shown to be slightly degraded due to combined environmental effects.

• Journal of Fashion Business
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• v.23 no.4
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• pp.100-111
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• 2019

In this study, the dyeing properties and functionalities of Crataegi fructus extract were investigated for the purpose of application to new natural dye resources. The effects of dyeing conditions(concentration of dye, dye bath temperature, dyeing duration and dye bath pH) and mordanting on dye uptake and color changes were also examined. The study also estimated the colorfastness, antibacterial properties, and ultraviolet protection properties of the dyed and mordanted silk fabrics. The dye uptake increased in tandem with the dye concentration and dye bath temperature. The highest K/S values were obtained at the following conditions: a dye concentration of 100%(v/v), a dyeing period of 60 minutes, a dye bath temperature of $90^{\circ}C$, and a dyeing pH of 3. The colorfastness of the material when dry cleaned or rubbed ranged from good to excellent and fastness to light was rated at grade 2-3. The change in the color grade when exposed to washing was not good; however, the stain of washing fastness was good at a range of 4-5. In regards to the functional property aspects, the dyed and mordanted fabrics exhibited excellent results with a 99.9% reduction rate, and excellent ultraviolet protection factors.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.1
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• pp.98-103
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• 2007

We made a oriental herbal medicine storage system and studied a preservation characteristic of oriental herbal medicine in this research. The lamp(OZ-Lamp) in a storage system is the low pressure ultraviolet lamp which radiates the sterilizing and ozonic rays. We made research ozone generation and electric discharge characteristic of a oriental herbal medicine storage system, which have radiation feature of ultraviolet rays of a short wavelength to be happened in the electric discharge. Also, we made research an ingredient and quality characteristic of oriental herbal medicine according to ozone treatment storage.

• Transactions on Electrical and Electronic Materials
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• v.11 no.4
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• pp.186-189
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• 2010

Nano-sized MgO single crystal powders have recently been reported to emit ultraviolet by stimulation of electrons in a vacuum. In this study, nanocrystalline MgO powders were applied to a xenon plasma flat fluorescent lamp (FFL) for a liquid crystal display backlight to improve its emission efficiency through the extra ultraviolet from the nano-MgO crystals. For comparison, a MgO nano-thin film was applied directly on the phosphors inside a lamp panel through e-beam evaporation. Adding MgO nano-crystal powders to the phosphors improved the luminance and efficiency of FFLs by around 20% and MgO nano-crystal coverage of 40% of the phosphor provided the best FFL emission characteristics; however, application of MgO thin film to the phosphors degraded the emission characteristics, even compared to FFLs without MgO. This was due to insufficient ultraviolet stimulation of the phosphors and the crystallinity and low secondary electron coefficient of the MgO.

• Journal of the Korea Society of Computer and Information
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• v.26 no.2
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• pp.119-124
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• 2021

In this study, we propose an antibacterial efficiency according to the direction of UV irradiation. In the experiment, we measured the effective irradiation angle of UVC using S.aureus, a Gram-positive bacterium, and the variation of the antibacterial region according to the distance according to the direction of ultraviolet irradiation. Also, as a method to increase the antibacterial efficiency during horizontal irradiation of ultraviolet rays, we tested reflecting leaking UVC. As a result, the angle of ultraviolet irradiation was measured smaller than the product description, and in the case of the antibacterial area according to the direction of ultraviolet irradiation, the distance from the sample was increased during vertical irradiation, and the antibacterial area was increased as the distance from the sample was closer during horizontal irradiation. In addition, it was confirmed that antibacterial efficiency can be increased by reflecting leaking UVC during horizontal irradiation of UVC.

• Bulletin of the Korean Space Science Society
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• 2004.04a
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• pp.51-51
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• 2004

KAISTSAT-4 is to be launched in August 2003 into an orbit at 800 km altitude with the intended mission shared between astrophysics and space physics. The primary objective of its astrophysics mission is to provide spectral sky survey data of hot Galactic plasmas in the far-ultraviolet wavelength range. Far-Ultraviolet Imaging Spectrograph (FIMS) is sensitive to emission line fluxes in 900 - 1175 $\AA$ and 1335 - 1750 $\AA$. (omitted)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.295-298
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• 2001

This paper presents mechanical properties and weatherability of FRP pole used for a distribution line about high strength and good insulation properties. The experiment strength obtained in cantilever beam test are comparable to ES standards. The environmental factors, such as elevated temperatures, high humidity, and corrosive fluids, and ultraviolet(UV) rays, influence on the performance of Polymeric matrix composite.

• Journal of the Institute of Convergence Signal Processing
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• v.16 no.3
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• pp.96-101
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• 2015

A tongue coating evaluation method for WTCI(Winkel Tongue Coating Index) is proposed in this paper, which is used as the diagnostic criteria in the tongue diagnosis. This method uses the color channel analysis and tongue coating extraction from the ultraviolet tongue image. Proposed method analyzes the histogram distribution of the respective color channel for extracting a tongue coating, and performs the verification test from the selected color channel in the tongue coating extraction. Also, Objectivity of the tongue diagnostic criteria is verified by the artificial sample and real-tongue image experiments. In order to evaluate the performance of the proposed Computerized Assistant WTCI Evaluation method, after verifying a measurement accuracy by using the artificial sample images, and applying to the various real-tongue image of subjects. As a result, the proposed WTCI method is very successful.

• Textile Coloration and Finishing
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• v.23 no.3
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• pp.179-186
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• 2011

For the application of Jeju scoria scattered around the island as a natural dye, cotton fabrics were dyed with the dye and their properties were measured including dyeability, colorfastness, antibacterial activity, deodorization efficiency, ultraviolet protection, and far-infrared emission. The dyed cotton fabrics were in yellowish red and optimal dyeing conditions were obtained with a colorant concentration of 25%(o.w.b) at a temperature of $80^{\circ}C$ for the dyeing time of 120 minutes. The ratings of colorfastness to light, rubbing, perspiration, and washing were 8, 5, 5, and 4~5 respectively. After 15 wash cycles, colorfastness remained as much as 4~5 rating. The cotton fabric dyed with Jeju scoria demonstrated excellent antimicrobial activity and deodorization efficiency of 99.9% and 93.9% respectively. Ultraviolet protection factor was 50+. Far-infrared emission rate and far-infrared emission intensity were 90% and 362(W/$m^2{\cdot}{\mu}m$) respectively. The Jeju scoria can be introduced as a new colorant for the natural dyeing of cotton.