• Textile Coloration and Finishing
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• v.17 no.6 s.85
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• pp.27-35
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• 2005

Conventional pad- dry-cure(thermo-fixation) process usually produces functional performance on both sides of a fabric. UV curing technique was applied to impart water- and oil-repellent finish effective only on the face of a PET knitted fabric. The preferential one-side coating, by virtue of the limited penetration of UV light, was achieved by W curing after padding of a fluorocarbon agent without special coating or printing equipments. The difference in the functional property of face and back sides was examined by measuring water and oil repellency at each side of the treated fabric. The influence of pre/post-irradiation dose and agent concentration on the performance of the finished fabrics were investigated. While increase in both resin concentration and post-irradiation did not have significant effect on the finish, UV pre-irradiation of PET fabrics caused remarkable influence presumably due to appropriate surface modification of PET fabrics required for facile wetting of the resin. The dimensional stability and color change of the UV cured fabrics measured by FAST and reflectance spectrophotometry showed significantly decreased color difference and increased percent extension compared with the samples pre-irradiated without agent application.

• Journal of the Korean Geotechnical Society
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• v.29 no.1
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• pp.13-22
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• 2013

This paper presents the results of a numerical investigation into the behavior of retaining wall subject to cycles of wetting and drying due to rainfall. The stress-pore pressure coupled finite element modeling strategy was first established for stimulating the wall behavior. A series of finite element analyses were then performed on a range of conditions including different rainfall and backfill conditions. The results indicated that the rainfall intensity was the primary influencing factor for the wall behavior. Also revealed was that the pre-rainfall condition determines the magnitudes and the distribution of matric suction which in fact has a significant impact on the behavior of wall during a major rainfall. This result demonstrates the importance of incorporating the pre-rainfall condition for numerical modeling of walls during heavy rainfall. Practical implications of the findings from this study are discussed in great detail.

• Corrosion Science and Technology
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• v.7 no.5
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• pp.243-251
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• 2008

Magnesium alloys become popular research topic in last decade due to its light weight and relatively high strength-to-weight ratio in the energy aspiration age. Almost all structure materials are supposed to suspend stress. Magnesium is quite sensitive to corrosive environment, and also sensitive to environmental assisted cracking. However, so far we have the limited knowledge about the environmental sensitive cracking of magnesium alloys. The corrosion fatigue (CF) test was conducted. Many factors' effects, like grain size, texture, heat treatment, loading frequency, stress ratio, strain rate, chemical composition of environment, pH value, relative humidity were investigated. The results showed that all these factors had obvious influence on the crack initiation and propagation. Especially the dependence of CF life on pH value and frequency is quite different to the other traditional structural metallic materials. In order to interpret the results, the electrochemistry tests by polarization dynamic curve and electrochemical impedance spectroscopy were conducted with and without stress. The corrosion of magnesium alloys was also studied by in-situ observation in environmental scanning electron microscopy (ESEM). The corrosion rate changed with the wetting time during the initial corrosion process. The pre-charging of hydrogen caused crack initiated at $\beta$ phase, and with the increase of wetting time the crack propagated, implying that hydrogen produced by corrosion reaction participated in the process.

• Korean Journal of Medicinal Crop Science
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• v.21 no.5
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• pp.394-400
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• 2013

This study was carried out in order to examine the germination characteristics of Atractylodes japonica seeds, and it was to develop the more efficient pre-treatment and production system of the seeds. Experiment was performed by two ways-temperature control (10, 15, 20, $25^{\circ}C$) and shading treatment (full sunlight, 35, 50, 75, 95% of full sunlight). Seed pre-treatment before the each experiment was carried out by temperature (with low temperature and wetting treatment (LTW) for 0, 15, 30, 45 and 60 days) and shading treatment (with drying at room temperature (DRT), drying at low temperature (DLT) and water soaking (WS) for 48 hours). Seeds of A. japonica were germinated well under temperature control (overall 85.3~100%), especially high temperature. And, the seeds pre-treated with LTW for 45 days germinated with a 100% success rate. Under the surveying shading treatment, the highest germination rate was 95.8% with DRT and overall 63.2~95.8%. Germination rate under seeds with WS was 63.2~7.8%. As a result of surveying the whole experiment, A. japonica seeds don't need to pre-treat cause of high germination, but if it is performed with LTW for a certain period of time, it would be more productive.

• Magazine of the Korea Concrete Institute
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• v.8 no.1
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• pp.121-129
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• 1996

본 연구에서는 대기 습도변화에 의한 콘크리트 보수체(기층 콘크리트/보수 모르터)의 파괴현상을 조사하기 휘해서 보수체내의 비정상적인 습도분포를 계산하였다. 계산된 습도분포에 의해서 기층과 보수층 경계면 부위의 습도차이가 보수층 두께(0.5~2.5cm)와 보수작업전 기층 콘크리트 표면의 습윤처리시간(0~72hr)을 주요 변수로 하여 조사되었고, 이는 주로 시멘트 모르터로 보수된 접촉면이 없는 보수체에서 수행되었다. 계산 및 조사결과 보수층 두께가 감소하고 습윤 처리시간이 증가할수록 경계면 부위의 습도차이는 감소하는 경향을 보였고, 특히 보수후 습도차이가 음수값이 될 때의 시간을 하나의 수식으로 표시하였다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.118-119
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• 2018

The purpose of this study is to investigate the compressive strength and mixing properties of the lightweight block, which has been manufactured without the pre-wetting process, in the lightweight block using domestic artificial lightweight aggregate. The test results of the specimens produced within 30 minutes after the preparation showed high compressive strength but poor permeability. Therefore, the elapsed time after the manufacture, which is expected to have required compressive strength and permeability, was about 60 minutes in this study.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.136-137
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• 2020

This study compared and analyzed the fluidity and strength characteristics of mortar using the recycling water, indicates strong alkali properties, as pre-wetting water of artificial light aggregate to increase usage ratio of recycling.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.262-269
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• 2013

This study was carried out in order to examine the germination characteristics of Ligularia fischeri seeds, and it was to develop the more efficient pre-treatment and production system of the seeds. It was performed by two ways - temperature control (10, 15, 20 and $25^{\circ}C$) and shading treatment (Full sunlight, 35%, 50%, 75% and 95% of full sunlight). Seed pre-treatment before the each experiment was carried out by temperature (with low temperature and wetting treatment (LTW) for 0, 15, 30, 45 and 60days) and shading treatment (with drying at room temperature (DRT), drying at low temperature (DLT) and water soaking (WS) for 2 days). Seeds of L. fischeri were, regardless of seed pre-treatment, germinated well at $10^{\circ}C$ and the more temperature went up, the more germination rate went down. As a result of surveying shading treatment, 75% shading with DRT was the highest germination rate (68.1%) and 95% shading with WS was the lowest germination rate (48.6%). It was showed over-growth under 95% shading treatment experiment and withered in the full sunlight. As a result of surveying the whole experiment, L. fischeri seeds pre-treated with LTW for 15 days germinated well at $10^{\circ}C$ and under 50~75% shading treatment.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.14-14
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• 2001

Nitride films such as TiN, CrN etc. deposited on glass by PVD processes have been developed for many industrial applications. These nitride films deposited on glass were widely used for not only decorative and optical coatings but also wear and corrosion resistance coatings employed as dies and molds made of glass for the example of lens forming molds. However, the major problem of nitride coatings on glass by PVD process is non-uniform film owing to pin-hole and micro crack. It is estimated that nonuniform coating is influenced by a different surface energy between metal nitrides and glass due to binding states. In this work, therefore, for the evaluation of nucleation and growth mechanism of nitride films on glass TiN and CrN film were synthesized on glass with various nitrogen partial pressure by unbalanced magnetron sputtering. Prior to deposition, for the examination of relationship between surface energy and film microstructure plasma pre-treatment process was carried out with various argon to hydrogen flow rate and substrate bias voltage, duty cycle and frequency by using pulsed DC power supply. Surface energy owing to the different plasma pre-treatment was calculated by the measurement of wetting angle and surface conditions of glass were investigated by X-ray Photoelectron Spectroscopy(XPS) and Atomic Force Microscope(AFM). The microstructure change of nitride films on glass with increase of film thickness were analyzed by X-Ray Diffraction(XRD) and Scanning Electron Microscopy(SEM).

• Analytical Science and Technology
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• v.30 no.6
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• pp.319-328
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• 2017

The identification of explosive residues on specimens obtained from an explosion event is a crucial factor for assessing the cause of the explosion. In order to detect the components of explosives, the explosive residues deposited on surfaces are commonly extracted using swabbing materials pre-wetted with an organic solvent. The residues are then analyzed with analytical instruments such as LC/MS and CE/MS. Most conventionally used swabbing media such as cotton swabs or cotton tip swabs seem unsuitable for extracting explosive residues from the surface of a large area of clothes because the swabbing materials tend to be damaged easily, and because only a relatively small amount of explosives is collected. To overcome these problems, we have introduced a novel wiper ($215{\times}210mm$, single layer, Yuhan-Kimberly, Republic of Korea) as a swabbing material to recover representative organic explosives, namely, TNT, RDX, tetryl, HMX, PETN, and NG, from a large area of clothes. Different sides of the wiper, which was folded in half five times, was used to swab the surface of a clothing. We compared this novel wiper with a cotton swab and a cotton tip swab in terms of the recovery efficiency for the aforementioned organic explosives by pre-wetting with methanol, acetone, and acetonitrile, respectively. We identified that this novel wiper collected a significantly higher amount of organic explosive residues than a cotton swab or a cotton tip swab when using methanol as an extracting solvent.