• 산학경영연구
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• 제13권
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• pp.263-273
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• 2000

벤츠(현 다임-클라이슬러)자동차회사는 새로운 공장을 미국 앨라배마 주 Vance 지역에 건설하고 이곳 공장으로부터 스포츠-레저용의 4륜 구동 M-class 자동차를 생산하고 있다. 이 벤츠공장의 생산라인은 차체형성공정, 도장공정, 그리고 엔진조립 공정으로 나누어져 있고 이들 생산라인사이에는 한 라인에서의 고장(down)이 다른 라인에 파급되지 않도록 완충라인(Buffer)이 설치되어 있다. 본 연구의 목적은 일정한 비율의 고장률을 각 생산라인에 적용시켰을 때 주어진 생산목표(270대)를 달성할 수 있는지, 만약 달성할 수 없다면 가장 문제가 되는 생산라인은 어디인지, 또 생산라인 사이에 존재하는 완충라인이 어느 정도의 완충역할을 하는지, 최적의 생산능력을 유지하기 위한 완충라인의 크기는 어느 정도인지 등, 각종 생산라인의 운영지침(operation policy)들을 시뮬레이션 기법을 이용하여 탐색한 후 병목생산시설(bottleneck)을 찾아내는 것이다. 본 연구를 위한 시뮬레이션 도구로는 ARENA를 이용했고 20일 간의 시뮬레이션 결과를 종합하여 분석하였다. 또 신뢰구간 95% 범위에서 각 생산라인의 최대 생산능력도 측정하여 실제 생산대수와의 차이를 규명할 수 있는 근거를 제공하였다.

• 대한토목학회논문집
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• 제40권1호
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• pp.77-85
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• 2020

현재 국내의 대형 인프라시설물의 유지관리를 위해 생애주기비용분석 방법을 도입하고 있다. 그러나 시설물의 위치 및 주변환경 등의 조건을 반영한 유지관리 모델을 적용하는 사례가 많지 않다. 적절한 유지관리 전략을 수립하기 위해서는 시설물의 환경조건을 반영한 비용예측, 열화모델, 불확실성을 반영한 의사결정모델이 수립되어야 한다. 본 연구에서는 발전구조물에 적용되는 도장 사양을 대상으로 유지관리 방법과 판단기준에 따라 사용자의 의사결정에 따른 장기적인 비용 계획 및 관리를 할 수 있는 경제성 분석 모델을 개발하였다. 경제성 분석 모델의 적용을 위하여 도장열화실험을 통하여 도장의 성능을 평가하였으며, 제안 경제성 분석 모델에 적용하여 각각의 적용도장 사양(우레탄, 폴리실록산, 불소)에 따른 경제성 분석결과를 확인하였다. 본 연구에서는 도장의 성능보다 보수 주기의 선정과 개발 모델을 적용한 평가 방법을 제시한 결과로 도장에 국한되지 않더라도 유지관리 방안 수립 시 보수 주기 등을 위한 기초적인 자료로 활용을 기대할 수 있을 것으로 판단된다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.395-400
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• 2005

The ship hull part is always exposed to severe corrosive environments. Therefore, it should be protected in appropriate ways to reduce corrosion problems. So there are two effective methods in order to protect the corrosion of ship hull. One is the paint coating as a barrier between steel and electrolyte (seawater) and the other is the cathodic protection(CP) supplying protection current. In the conventional design process of the cathodic protection system the required current densities of protected materials have been used. However, the anode position of field or laboratory experiment for obtaining the required current density for CP is significantly different from anode position for real structures. Therefore, the recent CP design must consider the optimum anode position for potential distribution equally over the ship hull. The CP design companies in the advanced countries can obtain the potential distribution results on the cathodic materials by using the computer analysis module. This study would show how to approach the potential analysis in the field of corrosion engineering. The computer program can predict the under protection area on the structure when the boundary condition and analysis procedure are reasonable. In this analysis the polarization curve is converted to the boundary condition in material data.

• 한국멀티미디어학회논문지
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• 제18권6호
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• pp.734-741
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• 2015

Coating is a type of paint. It protects a product forming a film layer on the product and assigns various properties to the product. Coating is one of the fields which is being studied actively in the polymer industry. Importance of coating in various industries is more increased. However, mixing process has been performing in dependence on operator's experience. In this paper, we found the relationship between each data from coating formulation process. We propose a framework to analyze the coating formulation process as well. It can improve the coating formulation process. In particular, the suggested framework may reduce degradation and loss costs due to absence of standard data which is accurate formulation criteria. Also it suggests responses to errors which can be occurred in the future through the analysis of the error data generated in mixing step.

• Environmental Analysis Health and Toxicology
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• 제18권1호
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• pp.63-67
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• 2003

Benzoic acid is produced about 700 tons/year in Korea as of 1998 survey. Most is used as a stabilizer in the processes of synthesis of pharmaceuticals and dyes. It is also used for ingradient of paint, disinfections, and antifungals. Due to the antioxidant activity of benzoic acid, the chemical is also used as food preservatives. Although the chemical is widely used in Korea, exposure levels in air, water, soil or sediment have not been monitored or estimated so that risk evaluation of benzoic acid was not possible. In this study, distribution of the chemical among environmental media was estimated using EQC model based on the chemical-physical properties. In Level I and II of which the chemical are hypothesized in equilibrium and no transfer through the media, more than 93％ of benzoic acid are estimated to be distributed in water. However, in Level III of which non-equilibrium and intermedia transfer could be occurred, the chemical is estimated to distributed to soil, 64％ and water,35% as of total amount.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2006년도 춘계공동학술대회 논문집
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• pp.1350-1356
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• 2006

The old technique of sandblasting which has been used for paint or scale removing, deburring and glass decorating has recently been developed into a powder blasting technique for brittle materials, capable of producing micro structures larger than $100{\mu}m$. In this paper, The surface characteristics of powder blasted glass surface were tested under different blasting parameter. Finally, we proposed a predictive model for powder blasting process using a neural network. A detailed analysis of the simulation results has been carried out and compared with experimental results.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.295-298
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• 1997

Recycl ing of PP/EPR based bumper coated with polyester urethane paint has been per formed by chemical decoating method. Electronic Speckle Pattern Interferometry (ESP11 has been applied to characterize the deformation of polyolef in based bumper. In additon, physical properties and processability of recycled materials have been investigated by dynamic mechanical thermal analysis, impact test and melt flower index measurement. The results show that the deformation ratio of recycled material is higher than that of virgin one. The morphological change of EPR, degree of distribution and dispersion during the recycling process seem to be the most important factor for the deformation and the mechanical properties of recycled materials. The experimental results obtained show that ESPI is very powerful technique to study the thermal mechanical property of polyolefin bumper system.

• Journal of the Korean Wood Science and Technology
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• 제44권4호
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• pp.589-599
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• 2016

Korean wooden cultural heritages are treated by flame retardants to protect fire hazards. Two types of flame retardants are used to treat wooden cultural heritage. These flame retardants cause some problems such as surface whitening, discoloration, and cracks due to the chemical reaction caused by Korean traditional wood painting (Dancheong), flame retardant and wood humidity. The Korean government is trying to cut down on the amount of flame retardants for the wooden cultural heritage because of these problems. This study was carried out to find the cause of whitening by flame retardants treatment. The reaction between pigment and flame retardant chemicals was analyzed by infrared spectroscopy.

• 한국기계가공학회지
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• 제11권6호
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• pp.183-188
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• 2012

This study was carried out to design the spray nozzle tip for airless spray coating. Airless spray coating is the process of coating an object with a liquid spray of paint or other fluid. The nozzle tip controls the fluid flow rate and creates back pressure in the system. The nozzle tip also defines the spray pattern by the size and shape of the orifice. The spray pattern of nozzle tip was investigated numerically using ANSYS CFX ver. 14.0. It was observed that performance result of designed nozzle tip was correspond well, compared with that of GARCO nozzle tip.

• 대한안전경영과학회지
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• 제19권1호
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• pp.115-122
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• 2017

This study analyzed that the standard of school supplies affects the satisfaction of certification. Safety requirements of school supplies in the Republic of Korea is enforced by court duty certification. Therefore, a test was conducted to compare the safety requirements of the United States and Europe and the survey was conducted to know how much manufacturers and importers are satisfied with the certification. To prepare management measures for harmful substances contained in children's product, XRF(X-ray Fluorescence Spectrometry) is utilized to analyze lead(Pb) and cadmium(Cd) in PA(paint), SP(sheet) and PVC(Poly Vinyl Chloride). The results of comparative analysis of ICP(inductively coupled plasma) is analyzed statistically with measured values.