• 한국정밀공학회지
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• 제11권4호
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• pp.165-173
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• 1994

Retroreflector is different from other reflecting surfaces as it mades reflection in which radiation is returned in directions close to its incoming direction. Because of this characteristics, retroreflectors find many applications in traffic safety related areas. Retroreflectors are usually made using comer cubes, or partially coated glass beads. These glass beads can be made very small, so that they can be coated on sheets or mixed with paints. The design of glass type retroreflector depends on glass bead's shape and material, and its optical characteristics are related to the refractive index of glass. In this paper, a method of anlyzing glass bead type retroreflector's sptical characteristics with respect to shape and optica property of the glass, is presented. First, the coefficient of retroreflection, which is a measure of retroreflector's optical characteristics, is derived analytically using geometrical optics method. And the result is plotted using numerical methods. The results show good match with those obtained experimentally, which were supplied from a commercial retroreflector manufacturer.

• 폴리머
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• 제34권4호
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• pp.306-312
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• 2010

Triphenylvinylsilane (TPVS) containing vinyl acetate (VAc), butyl acrylate (BA), and Nmethylolacrylamide (NMA) copolymers were prepared by emulsion polymerization. The polymerization was performed at $80^{\circ}C$ in the presence of auxiliary agents and ammonium peroxodisulfate (APS) as the initiator. Sodium dodecyl sulphate (SDS) and Arkupal N-300 were used as anionic and nonionic emulsifiers, respectively. The resulting copolymers were characterized by using Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and dynamic light scattering (DLS). Thermal properties of the copolymers were studied by using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The morphology of copolymers was also investigated by scanning electron microscopy (SEM) and then the effects of silicone concentrations on the properties of the TPVS-containing VAc-acrylic emulsion copolymers were discussed. The obtained copolymers have high solid content (50%) and can be used in weather resistant emulsion paints as a binder.

• 산업융합연구
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• 제1권2호
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• pp.17-31
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• 2003

Many risk factors with the onset of Low Back Pain(LBP) have been identified, however, lifting out of Manual Material Handling(MMH) was the most important factor to the LBP. Injuries due to lifting took account for 34.0%(227,291) out of the total overexertion in MMH(668,084). The weight, vertical location, twist angle, lifting frequency, and lifting posture were reviewed in this study. Technical information for using the revised lifting equation to evaluate a variety of two - handled manual material handling tasks was suggested. To measure worker's fatigue in lifting task, Lifting Index Simulator(LIS) was create under the revised NIOSH(National Institute for Occupational Safety and Health) lifting equation. For the implementation of the LIS, data was collected in A company manufactures various paints in Si-Wha industrial complex, Kyunggi-Do. The results of the Lifting Index(LI) were analyzed by MANOVA to find the relation with lifting variables collected. It was found that horizontal distance, vertical distance, travelling distance and frequency were significant at the 0.01 level and weight was significant at the 0.05 level. The purpose of this paper is to reduce the chronical low back pain for the manual material handlers.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2019년도 하계학술대회
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• pp.163-165
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• 2019

The task of image denoising is gaining popularity in the computer vision research field. Its main objective of restoring the sharp image from given noisy input is demanded in all image processing procedure. In this work, we treat the process of residual hair removal on faces images similar to the task of image denoising. In particular, our method removes the residual hair that presents on the frontal or profile face images and in-paints it with the relevant skin color. To achieve this objective, we employ a deep neural network that able to perform both tasks in one time. Furthermore, simple technic of residual hair color augmentation is introduced to increase the number of training data. This approach is beneficial for improving the robustness of the network. Finally, we show that the experimental results demonstrate the superiority of our network in both quantitative and qualitative performances.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.153-154
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• 2017

Graphene is a nanomaterial and is known to have very high mechanical strength, thermal and electrical properties. However, graphene is known to be difficult to disperse among carbon-based materials due to van der Waals force. In this study, to solve the dispersion problem of graphene nanoplatelet, oxidized graphene nanoplatelet was prepared by oxidizing GNP in nitric acid. The prepared GO was dispersed in ethanol and distilled water before incorporation into the epoxy paint to confirm dispersibility. In addition, GNP/Epoxy and GO/Epoxy tensile specimens were prepared by mixing GNP and GO at 0.1, 0.3, 0.5 and 1.0 wt.% In epoxy coatings and tensile stress-strain characteristics were investigated.

• Journal of Smart Tourism
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• 제3권1호
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• pp.35-39
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• 2023

This research note probes the largely ignored sphere of smart tourism curriculum as destinations and institutions seek to develop graduates ready to embrace the demands and challenges of future work environments where technology has a ubiquitous presence. This knowledge gap is somewhat surprising, even as destinations progress towards smart tourism futures, without necessarily clarifying what human resources need to possess in the coming decades. Drawing from available smart tourism curriculum across the globe, and emergent trends associated with Generation Alpha and Beta, this research note paints a timely picture of how smart tourism curriculum should be designed and developed to meet the needs of industry and consumer demands and expectations.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.67-68
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• 2023

This paper reports on the synthesis of paraffin-based phase change materials (PCMs) designed for use in solar reflective paint (SRP) as a thermal energy storage (TES) medium. These PCMs are prepared using the sol-gel process and are encapsulated in silica. The focus of this research is to evaluate the suitability of these synthesized PCMs for efficient thermal energy storage within SRP applications. The obtained PCMs have nanometric dimensions, which make them well-suited for integration into paint formulations. The study also includes a thorough analysis of the chemical, thermal, and structural stabilities of these materials, confirming their applicability in solar reflective paint.

• 한국응용과학기술학회지
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• 제30권1호
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• pp.116-126
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• 2013

Glycol ethers는 페인트에 흔히 사용되는 ethylene glycol의 alkyl ethers에 기반을 둔 용제들이다. 이 용제들은 일반적으로 저분자량 에테르와 알코올의 용제 친화적 성질과 더불어 더 높은 비등점을 가지고 있다. Union Carbide Corp.는 "Glycol ethers"를 하나의 미국 상표로 등록했으며, 이는 제약, 자외선차단제, 화장품, 잉크, 염료 및 수성페인트에서 찾아볼 수 있다. 반면 glycol ethers는 그리스 제거제, 세제, 에어로졸 페인트와 접착제에서도 발견된다. 대부분의 glycol ethers는 수용성, 생분해성이며, 아주 적은 수의 glycol ethers만이 유독성이라고 여겨진다. 그러므로 glycol ethers는 환경에 부작용을 낳을 것 같지는 않다. 최근 연구는 glycol ethers에 작업상 노출되는 것이 남성 정자의 저 운동성과 연관이 되어 있다고 제시했지만, 이는 다른 이들에 의해 반박되어지고 있다. 본 연구에서는 3가지 종류의 glycol ethers의 피부침투성에 관해 용제와 세제의 조합을 사용하여 시험관을 통해 연구한다. Methyl glycol ethers, ethyl glycol ethers and butyl glycol ethers의 흡수는 쥐의 피부를 통해 시험관에서 측정되었다. Epidermal membranes는 Franz diffusion cells에 세워졌으며, 그들의 PBS 침투율은 glycol ethers가 epidermal surface에 적용되기 전, 피부의 보전을 위해 처리하였다. 개별 glycol ethers의 흡수율은 최대 흡수 파장(${\lambda}_{max}$)에서 흡광도를 측정하여 결정하였으며, 침투율의 측정은 esters와의 접촉을 이유로 장벽 기능 내 불가역 변화를 정량화하였다. 시험관 실험 결과 glycol ethers의 종류는 methyl glycol ethers > ethyl glycol ethers > butyl glycol ethers의 순에 따라 빠르게 나타났다. 피부침투는 저분자량 피부침투, 친수성과 같은 화학적구조의 차이에서 유익했다. 이는 분배계수와 용해 방법 및 수동확산이 전달이 고려되는 곳에서 속도를 올렸기 때문이다.

• 한국약용작물학회지
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• 제8권2호
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• pp.109-116
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• 2000

115 종의 생약재 중에서 식품부패성 및 병원성 미생물을 대상으로 항균활성을 나타내는 생약자원을 검색한 결과 식품부패성 세균 Bacillus subtilis에 강한 항균활성을 보인 것은 단삼, 관중, 가자, 독활, 파고지, 오미자이었으며, 식중독균인 효모 Candida albicans IFO6258에 대해서는 지모와 관중 두 생약재가, 식품부패성 효모 Schizosaccharomyces sp.에 대해서는 지모, 관중, 원지가 각각 강한 항균 활성을 보였다. Streptococcus mutans에 대해서는 관중, 단삼, 소목, 방기, 오미자, 오배자, 고삼, 목향이 강한 항균 활성을 보였다. 피부 각층 및 모발에 침입하여 피부병을 야기하는 백선균 Trichonphyton mentagrophytes에 대해서는 지모, 강황, 목향, 호장근, 지유, 황금, 가자들이 항균활성을 나타내었다 . 항균spectrum이 넓으면서 비교적 항균활성이 강한 관중, 단삼, 가자, 황금에 항균활성이 강한 생약자원인 가자, 계피, 방기, 황금등의 생약재를 각각 1 : 1로 혼합한 추출물에 대한 항균활성을 조사한 결과 모든 혼합 추출물에서 단독 추출물 보다 강한 항균활성을 나타내었다.

• 한국해양공학회지
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• 제25권2호
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• pp.85-91
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• 2011

Many protection methods such as surface coating, electric protection, or other methods have been applied to the numerous steel structures widely used in continental and marine areas to control their corrosion, which is done from an economic point of view. Most of these steel structures are primarily protected by coating methods. However, some steel piles under seawater are protected by the electric protection method, that is, either using an impressed current or a sacrificial anode method. Furthermore, environmental contamination may cause a severely corrosive environment, which, in turn, causes the accelerated corrosion of steel structures. Subsequently, coated steel structures could deteriorate more rapidly than the designed lifetime because of the acid rain caused by air pollution, etc. Therefore, a coating of marine paint exposed to seawater, that is, underwater hardening painting, is increasingly required to be fast drying as well as highly corrosion resistant. In this study, five types of underwater hardening paints were prepared with different resin series and additives. Their corrosion and water resistances were investigated using electrochemical methods such as corrosion potential, polarization curves, impedance and cyclic voltammogram measurements, etc. Even though it is generally accepted that the corrosion resistance of bare steel tends to increase with a shift of the corrosion potential in the noble direction, the corrosion resistance of a sample with a coating exhibited a relatively better tendency when it had a lower corrosion potential in this study. The corrosion current density was also decreased with a decrease in the diffusion limiting current density, which may mean that there is some relationship between corrosion and water resistance. The S sample of the ceramic resin series showed the relatively best corrosion and water resistance among those of samples, while the worst corrosion and water resistance were observed for the R sample of the epoxy resin series. The corrosion and water resistance of those samples tended to deteriorate with an increase in the immersion days, and their corrosion and water resistances were considered to be apparently improved by the types of resin and additives.