• Journal of Conservation Science
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• v.34 no.5
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• pp.397-405
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• 2018

Currently, there are very few studies on Korean wall paintings. Therefore, this study discusses the current conditions of wooden paintings and the characteristics of the adhesive agent in the painting layer separation. Korean land pine was chosen as the support, while white oysters shells, orpiment, red ocher, Noerok, and azurite were used as pigments. With four adhesive agents, including animal glue, Gelidium, methyl cellulose, and PVAc (caparol binder), a comparative experiment was conducted, by dividing them into two concentrations, of 0.5% and 1.5%. The temperature, humidity, and ultraviolet rays, which are contributing environmental factors in cultural assets after fixing, were artificially investigated. After deterioration, observed color difference, fixing, and the surface. Results showed that the animal glue strongly fixing all the colored layers compared to the other adhesives; however, azurite had a partial change when used outdoors. With Gelidium, which functioned similar to animal glue, the azurite was affected by the ultraviolet rays; nevertheless, despite the variations in temperature and humidity, it had the best gripping force compared to the other adhesive agents. Methyl cellulose was glossy at a high concentration, and was relatively strong against rapid changes in temperature and humidity. PVAc significantly reduced the binding force, compared to other adhesive agents.

• Journal of the Korean Wood Science and Technology
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• v.45 no.1
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• pp.107-115
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• 2017

In this study, the surface check reduction effect of preservative-treated Korean larch round-wood was investigated by applying three physical treatments, such as incising, kerfing, and kiln-drying. Moreover, the possibility of long-term service life was also checked by comparing the depth of surface check and the penetration depth of preservative. A rapid gradient of wood moisture content between surface and center causes a surface check. Thus, the effect of reducing surface check was carried out at the lowest equilibrium moisture content (EMC) condition, temperature ($2^{\circ}C$), humidity (44.6%), in outdoor locations in Korea until the test specimens reach to the 8.6% EMC. As a result, the preservative-treated specimens without incising, kerfing, kiln-drying (Type C) could not ensure the long-term service life due to a large surface check. Because the surface check depth of all specimens was deeper than the penetration depth of preservative. In case of the incising treated specimens (Type I), 80% of them, the depth of surface check was not deeper than the penetration depth of preservative. However, when a kerfing was additionally treated (Type B), a possibility of happening deeper surface check than penetration depth of preservative was increased rather than Type I.

• Polymer(Korea)
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• v.34 no.4
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• pp.313-320
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• 2010

New cinnamate group-containing copolymers for a self-curable, humidity-sensitive polyelectrolyte and polymeric anchoring agents were prepared by copolymerization of [2-[(methacryloyloxy) ethyl]dimethyl]propyl ammonium bromide(MEPAB), methyl methacrylate(MMA), 3-(trimethoxysilyl) propyl methacrylate(TMSPM) and 2-(cinnamoyloxy)ethyl methacrylate(CEMA). Photocrosslinkable copolymer composed of MEPAB/MMA/TMSPM/CEMA＝70/20/0/10 were used for humidity-sensitive membrane, and those of 50/0/20/30 and 0/0/50/50 were used for polymeric anchoring agents. 3- (Triethoxysilyl)propyl cinnamate(TESPC) was also used as a surface-pretreating agent for the comparison of capability of attachment of polyelectrolyte to the electrode surface with polymeric photocurable silanecoupling agents. Pretreatment of the electrode substrate with anchoring agents was performed to form a cinnamate thin film on the electrode through covalent bonds. When the sensors were irradiated with UV light, the anchoring of a polyelectrolyte into the substrate was carried out via the [2$\pi$+2$\pi$] cycloaddition. The resulting sensors using polymeric anchoring agents and TESPC showed water durability with increase of resistance by 60~85%, which is corresponding to the reduction of 2.25~3.15%RH, after soaking in water for 24 h. They showed good hysteresis (-0.2%RH), response time (90 sec) and long-term stability at high temperature and humidity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1A
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• pp.53-59
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• 2010

Recently, NDTs (Non-Destructive Techniques) using infrared camera are widely studied for detection of damage and void in RC (reinforced concrete) structures and they are also considered as an effective techniques for maintenance of infrastructures. The temperature on concrete surface depends on material and thermal properties such as specific heat, thermal conductivity, and thermal diffusion coefficient. Different porosity on cement mortar due to different mixture proportions can show different heat behavior in cooling stage. The porosity can affect physical and durability properties like strength and chloride diffusion coefficient as well. In this paper, active thermography which uses flash for heat induction is utilized and thermal characteristics on surface are evaluated. Samples of cement mortar with W/C (water to cement ratio) of 0.55 and 0.65 are prepared and physical properties like porosity, compressive strength, and chloride diffusion coefficient are evaluated. Then infrared thermography technique is carried out in a constant room condition (temperature $20{\sim}22^{\circ}C$ and relative humidity 55-60%). The mortar samples with higher porosity shows higher residual temperature at the cooling stage and also shows reduced critical time which shows constant temperature due to back wall effect. Furthermore, simple equation for critical time of back wall effect is suggested with porosity and experimental constants. These characteristics indicate the applicability of infrared thermography as an NDT for quality assessment of cement based composite like concrete. Physical properties and thermal behavior in cement mortar with different porosity are analyzed in discussed in this paper.

• International Journal of Highway Engineering
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• v.11 no.2
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• pp.99-109
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• 2009

Fine-size exposed aggregate portland cement concrete pavements (FEACP) have surface texture of exposed aggregate by removing upper 2$\sim$3mm mortar of surface of which curing is delayed by using delay-setting agent. FEACPs have advantages of maintaining low-noise and adequate skid-resistance level during the performance period than general portland cement concrete pavements. It is necessary to ensure the durability environmental loading to prevent unexpected distress during the service life of FEACP. In the process of curing, volume change accompanied change in by moisture and temperature could be an important cause of crack in concrete to construct for successful FEACP, The use of chloride containing deicer may accelerate defects of concrete pavement, such as crack and scaling. This study aim to evaluate environmental loading resistance of FEACP, based on the estimation of shrinkage-crack-control-capability by moisture evaporation and scaling by deicer in freeze-thaw reaction.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.798-803
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• 2015

This study was conducted to predict the effect of door opening in wooden cultural heritages (WCHs) on their conservation environment. For this prediction, measured relative humidity (RH) and surface wood moisture content (MC) of inner part of wood columns in open wooden building and neighboring closed wooden building were compared with minimum RH, including the duration of minimum RH, and MC required for spore germination and resultant growth of wood-degrading fungi reported in some literatures. Moisture conditions, namely RH of inside wooden building and MC of wood was unsuitable for decay and sap-stain fungi all the year round; however, moisture conditions during summer season was suitable for spore germination and resultant growth of surface mold fungi, regardless of door opening. When compared, the duration of minimum (75%) or higher RH and the number of wood columns with MC level greater than the minimum MC (15%) during summer season, the surface mold related to the conservation environment of inside wooden building was somewhat better in open building than in closed building. Rather, doors should be opened in closed building for reducing indoor RH as a necessary measure during summer season when outdoor RH is high.

• Journal of the Korean Wood Science and Technology
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• v.35 no.4
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• pp.1-8
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• 2007

Japanese larch specimens with dimension of 2.5 (radial direction) ${\times}$ 2.5 (tangential direction) ${\times}$ 2.5 cm (longitudinal direction) were prepared to determine 3 different directional internal moisture movement coefficients and surface emission coefficients along the radial-, the tangential-, and the tangential-direction. 4 sides of each cubic specimen were wrapped with paraffin tape and rubber tape, leaving open the 2 opposite surfaces of interest, to provide one dimensional moisture movement during drying. The coefficients were determined at three different temperatures, 70, 50 and $30^{\circ}C$ and at two different relative humidities, 30 and 60%. Internal moisture movement coefficients inclusive of flow of free water and diffusion of bound water and water vapor were increased in the high temperature condition. The internal moisture movement coefficient in the longitudinal direction was about six times of those in transverse directions with radial value being 20% greater than the tangential. Surface emission coefficients were increased with temperature and decreased with surface moisture content. Using this results, moisture content (MC) profile and quantities of moisture evaporating in Japanese larch lumber could be predicted in dynamic drying situations.

• Journal of the Korean Magnetics Society
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• v.25 no.1
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• pp.4-9
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• 2015

This study was carried out to investigate a influence of humidity variation (%) on the magnetic properties and the surface flaws in the fabrication of Fe-based $Fe_{78}Si_9B_{13}$ amorphous alloy ribbon by Planar Flow Casting process. As a result, the size of the air pocket and the droplet which is observed in the contact surface and the free face of the amorphous alloy ribbon becomes large when the humidity increases and the size highly increases with the surface roughness at the same time. Especially, the surface roughness value which is made in the 65 % of the humidity is the lowest in the contact surface ($Ra=0.60{\mu}m$, $Rz=3.11{\mu}m$) and the free face ($Ra=0.47{\mu}m$, $Rz=3.00{\mu}m$). Also, in case of the soft magnetic property of the magnetic core which is made with the toroidal core of $23(OD)^*20(ID)^*20(H)$ size, in the sample of the amorphous alloy ribbon which is made in 65% of the humidity, the most excellent value is gained as $B_s(B_{700})=1.055T$, $H_c=0.083Oe$, permeability = 1,197 and core loss = 0.276W/kg.

• Journal of Conservation Science
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• v.32 no.4
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• pp.491-500
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• 2016

Fog is atmospheric in which tiny drops of water vapor are suspended in the air near the ground. Its form, occurrence, etc., change according to the temperature, relative humidity, wind and geographical features of the space around it. In particular, fog tends to occur near a source of water because of temperature and relative humidity difference. These days, climate change is increasingly affecting the occurrence of fog. Therefore the purpose of this study was to investigate how fog affects materials that are part of our cultural properties through outdoor exposure tests and artificial degradation. The degradation evaluation of materials as a function of fog occurrence frequency, showed that the color of metals changed noticeably, whereas dyed silk and Dancheong showed degradation on the surface and color differences but no particular tendencies. Therefore, damage prediction by color differences as a function of fog occurrence frequency was based on metal samples, which showed constant color differences. Through a comparison of the predictive value and color difference by outdoor exposure, the accuracy and applicability of the damage prediction formula was confirmed. If a more complex damage prediction formula is created, it is expected that prediction of the degree of material damage in the field would be possible.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.11a
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• pp.157-161
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• 1999

본 연구에서 직물의 열, 수분 전달특성과 KES-FB의 역학적 특성치, 직물표면의 fractal dimension을 측정하여 주관적 의복 착용 쾌적감을 예측하고자 하였다. 실험의복에 사용된 직물은 면 100% 평직물, 면/PET 혼방직물, 피치가공된 면/PET 혼방직물, PET 100% 평직물, 알칼리 감량가공된 PET 100% 크레이프 직물이었으며, 실험의복의 형태는 긴 소매 셔츠로 하였다. 착용실험은 온도 29$\pm$0.5$^{\circ}C$, 상대습도 75$\pm$2%RH, 기류 0.15m/s를 유지하는 항온항습실에서 실시하였고 36명의 여성 피험자(20-23세)들이 참여하였다. 의복 착용감의 하위 구성차원을 파악하기 위해 실험결과를 요인분석한 결과 5 개의 요인으로 추출되었다. 제 1 요인은 체온상승, 수분특성과 관련이 있는 온열.발한감이었으며, 제 2 요인은 무게ㆍ두께감, 제 3 요인은 회복특성감, 제 4 요인은 표면접촉감, 제 5 요인은 온냉감으로 구성되었다. 직물의 표면특성을 정량화하는 방법으로 도입한 fractal dimension 의 분석값들과 종래의 가장 보편적으로 이용되어 온 KES_FB 의 표면 특성치들이 주관적 착용쾌적감 예측에 얼마나 기여하는지 비교해 본 결과, 표면접촉감은 fractal dimension, 접촉점들의 총면적, 접촉점들의 평균 axis ratio, MMD, SMD와 높은 상관을 나타내었다. 또한 종합적 착용쾌적감에 대해서는 SMD 를 제외한 척도들이 유의한 상관을 보였으며, 그 중에서도 fractal dimension 과 접촉점들의 총면적은 0.8 이상의 높은 상관을 나타내었다. 착용쾌적감을 예측하기 위한 회귀분석결과에서는 fractal dimension 만으로 쾌적감의 74%가 설명되었으며 공기 투과도를 첨가하면 두 변수로 $R^2$=.792가 되었다. 설명되는 누적분산값은 67.18%였다.주관적 평가의 결과와 객관적 평가 결과를 이용해 마직물의 태를 평가하는 산출식을 제시하였다. 태 평가치의 경우 16가지 특성치를 모두 넣는 방법과 stepwise 방법, 또 Kawabatark 사용한 순차적 군 회귀법의 세가지 방법의 회귀식 중 16가지 특성치를 모두 넣는 방법의 결정계수가 가장 높았다.tosterone농도는 107.7$\pm$12.0 pmol／l이었고, 남성의 타액내 농도는 274.2$\pm$22.1 pmol／l이었다. 이상의 결과로 보아 본 연구에서 정립된 EIA 방법은 RIA를 대신하여 소규모의 실험실에서도 활용할 수 있을 것으로 사려된다.또한 상실기 이후 배아에서 합성되며, 발생시기에 따라 그 영향이 다르고 팽창과 부화에 관여하는 것으로 사료된다. 더욱이, 조선의 ${\ulcorner}$구성교육${\lrcorner}$이 조선총독부의 관리하에서 실행되었다는 것을, 당시의 사범학교를 중심으로 한 교육조직을 기술한 문헌에 의해 규명시켰다.nd of letter design which represents -natural objects and was popular at the time of Yukjo Dynasty, and there are some documents of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japanese Letter Jobcheso." Therefore, the purpose of this study is to look into the origin of the letter designs in t