• 한국주조공학회지
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• 제35권4호
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• pp.88-98
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• 2015

The effects of quenching and tempering temperatures on the tensile, impact and corrosion properties of A487 alloy cast with different C contents of 0.16, 0.19 to 0.23 wt.% were examined. The impact tests were conducted at $25^{\circ}C$ and $-60^{\circ}C$ and the immersion test was performed using 3.5% NaCl solution for 14 days. The quenching temperature affected the mechanical properties of A487 alloy cast, while the magnitude of change varied depending on the C content. The increase in tempering temperature showed the typical trend of decreasing tensile strength and increasing impact properties. The change in quenching and tempering temperature in this study did not affect the corrosion properties of A487 alloy significantly. The change in mechanical and corrosion properties of A487 with different C contents was discussed based on the microstructural and fractographic observation.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.77-81
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• 2010

This study deals with the analysis of color-difference and physical property of anti-corrosion coatings using at inside of concrete tank for drinking water. Because anti-corrosion coatings are effected by chemical attack, color and physical property are changed. So in this study when epoxy resin coatings of 3 types were received chemical attack by Cl- and NaOH, we present the co-relationship between color-difference and bond strength. For this study, we used the colorimetry, which can measure the degree of color difference on surface of materials. As the results, in case of Cl-, color change is appeared, bond strength also is decreased. From this experiment, we could know that color change due to chemical aging has the deep relationship with physical performance(bond strength) materials. further researches are needed.

• 한국자동차공학회논문집
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• 제9권3호
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• pp.51-59
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• 2001

A diesel engine oil formulated in KRICT and a commercial diesel engine oil (API CG-4) were tested by car and their Kinematic Viscosity, TAN, TBN, metal content, additive depletion, anti-wear property and IR analysis were analyzed. From the research, both of the tested oils had almost the same properties f3r the change of TAN and TBN, but the change of Kinematic Viscosity of formulated oil was slightly higher than that of commercial oil. The iron content in the commercial oil increased rapidly from 7000 km while that of the formulated oil was still low. These results were confirmed by the anti-wear test with a 4-ball wear test machine for the each samples. Also, for the commercial oil, the depletion factor of the Zn-DTP which was added as an anti-wear property did not change any more after 7000 km. But, that of the formulated oil changed continuously to 8000 km, which means that the ability to prevent wear of the sliding pairs exists for the formulated oil. From the analysis results of oil properties obtained by field test, it was found that the commercial oil could be used only within 7000 km, but the formulated oil could be used more than 8000 km without severe wear of the sliding parts in the diesel engine.

• The International Journal of Costume Culture
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• 제8권1호
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• pp.23-31
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• 2005

Mechanical properties and hand evaluation of wool/acrylic(W/A) blend knits were conducted before and after repeated washing to get the optimum W/A blending ratio, which could help achieve the optimum mechanical and hand properties of the knits. The five test fabrics using the yarns with different W/A blending ratios($\%$), 100/0, 70/30, 50/50, 30/70, 0/100, were knitted. The fabrics were washed by a rotating drum type washing machine. Then, objective mechanical and hand properties were evaluated by KES-FB, Kawabata evalution system for fabric. The results are as follows: there was no change in the hand value of the knitted fabric with the W/A-blended yarn caused by the change in the blending ratio before washing. After washing, however, the increase of acrylic's blending rate caused the bending property to decrease proportionally, while the friction coefficient of the surface property increased. Furthermore, the study showed that W/A 50/50 possesses the most superior tensile property and shearing property, which could attain the optimum blending ratio. Similar results in hand value were derived in all the samples. After washing, however, the increase in acrylic's blending rate caused a proportional decrease in KOSHI and an increase in FUKURAMI. In addition, W/A 50/50 gained the biggest NUMERI value, again corresponding to the optimum blending ratio. Similar results in total hand value were derived in all the samples before washing. After washing, though, all the total hand values decreased, and, as the wool fabric's blending rate increased, the total hand values proportionally decreased further.

• 통상정보연구
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• 제10권3호
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• pp.291-313
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• 2008

As digital economy has dramatically evolved, new intellectual property rights protection has emerged as a pivotal issue which companies need to actively restxnid to. At the new digital era, the possession of new intellectual property rights determines the company values, and thus the protection of new intellectual property rights is getting more importance in the dimension of global competitiveness. The paper analyzes the changing aspect of digital economy and e-commerce paradigm, and explores the protection plan of new intellectual property rights focusing on e-commerce and digital goods transaction so that it can help the companies to strengthen their global competitiveness. After various case studies, we can find out that even though the companies have difficulty in settling out the strategies and policy due to the radical change of cycle in internet-centered digital economy, companies need to establish the systemic strategic plan to protect the new intellectual property rights stage by stage. Also, appropriate legal, institutional basis to protect the new intellectual property rights should be rearranged. The unsloved problems which relates with the protection of new intellectual property rights will be left for next research project.

• 대한기계학회논문집
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• 제8권2호
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• pp.178-183
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• 1984

본 연구에서는 108개의 아르곤 입자가 Lennard-Jones의 포텐셜함수로 상호작 용하고 있는 고밀도 액체계에 높은 전단율울 작요시켜 외력에 의하여 물성의 변화가 일어나고 있는 비평형상태의 액체가 나타내는 현상을 분자동력학을 이용하여 미시적 인 관점에서 고찰하므로써, 높은 전단하중으로 인하여 윤활유 내부에서 전단응력이 발생하고, 이완되는 과정과 이로 인하여 점성이 저하하는등 비평형상태하의 물성변화 를 예측하는데 도움이 되고자 한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.1256-1259
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• 2006

The purpose of this study was to investigate the current status and influence factor in measuring the dynamic stiffness of damping materials. The property of the dynamic stiffness of damping materials was tested and analysed in condition such as the size of test samples and the change of relative humidity in heating chamber. Test results showed that the dynamic stiffness of after-heating was lower than that of before-heating in most samples and the change of relative humidity in heating chamber got little influence of the dynamic stiffness. The resonant frequency of test sample decreased $2{\sim}7Hz$ as the decrease of the size of sample. Because it was increased that total mass per unit area of sample, the change of dynamic stiffness had little influence.

• 경영과정보연구
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• 제18권
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• pp.21-40
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• 2006

The activation of an Real Estate transaction that be necessary correspond the user need of Internet suitably for be able to become safe and quick transaction of Real Estate transaction. We have been changed into a buyer center in the market of the while of a shalesman center that The taste of an immovable property buyer is various today. The area range of an Real Estate brokerage that take charge of real estate brokerage business have been reduced gradually that take the influence on Implementation of an Real Estate information system. The age of change of the environment which is bring the change of the mode of an real estate transaction that are leading the change of an Real estate circulation market. The paper is design for implementation of real estate transaction system that lead the period of new Internet and the purpose to accomplish the activation of an immovable property information system that offer an real estate service information

• Journal of the Optical Society of Korea
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• 제18권4호
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• pp.350-358
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• 2014

The collapse of Langmuir monolayers of arachidic acid (AA) on water at various rates of molecular area compression has been investigated in situ by imaging ellipsometry (IE). The thickness of the collapsed AA molecules, which are inherently inhomogeneous, was determined by IE with a spatial resolution of a few microns. For the analysis, we determined the dielectric function of AA monolayers from 380 to 1690 nm by conventional spectroscopic ellipsometry. Compression rates ranged from 0.23 to $0.94{\AA}^2/min$. A change of multilayer domains was observed in the in situ IE images. Lower compression rates resulted in more uniform collapsed films. Our experimental results correspond with previous theoretical simulations.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2004년도 학술.기술논문발표회
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• pp.33-37
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• 2004

Recently, Growing tendency for structure surface to use water repellent agent has increased steadily. But investigation of it's protection and durability property is not sufficient. Therefore, this paper shows the investigation about repellent property and micro structure's change in surface layer of mortar that is applied by water repellent agent. Water repellent property, absorption coefficient, air permeability, porosity and observation of micro construct was investigated according to water repellent agent type. The test results indicated that mortar applied water repellent agent appears tiny absorption coefficient, but air permeability is maintained. The reason is because silane solution is coating at capillary surface of a wall and minute pore structure is changeless.