• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1128-1129
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• 2006

Currently Chemical Mechanical Planarization (CMP) has become an essential step in the overall semiconductor wafer fabrication technology. Especially the CMP pad conditioner, one of the diamond tools, is required to have strong diamond cohesion. Strong cohesion between diamond and metal matrix prevents macro scratch on the wafer during CMP Process. Typically the diamond tool has been manufactured by sintered, brazed and electro-plated methods. In this paper, some results will be reported of cohesion between diamond and metal matrix of the diamond tools prepared by three different manufacturing methods. The cohesion force of brazed diamond tool is found stronger than the others. This cohesion force is increased in reverse proportion to the contact area of diamond and metal matrix. The brazed diamond tool has a strong chemical combination of the interlayer composed of Cr in metal matrix and C in diamond, which enhance the interfacial cohesion strength between diamonds and metal matrix.

• 폴리머
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• 제25권1호
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• pp.122-132
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• 2001

본 연구에서는 온도의 상승에 의하여 팽창하는 열팽창 기능을 가지고 있으면서 부피의 감소에 의하여 발생하는 압력의 손실을 상쇄시킬 수 있는 고무 치공구를 열가소성 고분자의 필름 함침공정에 적용하였다. 일반적인 압축성형공정에서는 온도의 상승에 의하여 수지가 용융되고 이에 수지가 함침됨에 따라 압력이 감소하지만, 고무 치공구를 사용한 경우에는 수지의 함침을 보상한 고무 치공구가 팽창하여 감소된 압력을 보상하기 때문에 급격한 압력의 강하를 억제할 수 있었다. 이렇게 수지의 함침에 따른 고무 치공구의 부피 팽창 그리고 이에 따른 수지 함침속도의 변화를 고려하여 고무 치공구를 이용한 필름 함침공정 모델을 제안하였다. 또한 고무 치공구를 사용하지 않는 일반적인 압축공정에 있어서 수지의 함침에 따른 섬유층 탄성력의 변화를 실험적으로 측정하여 단계적인 압축공정에 있어서 수지의 함침속도를 예측할 수 있는 모델을 제안하였다.

• 한국군사과학기술학회지
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• 제8권4호
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• pp.41-49
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• 2005

This work describes the ventilative NBC CPS(Nuclear Biological and Chemical Collective Protection Systems). The operational requirements of NBC CPS is derived using systems engineering approach. The NBC CPS system operational architecture which describes the operational concept of NBC CPS is proposed using a computer aided systems engineering tool.

• 제어로봇시스템학회논문지
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• 제8권5호
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• pp.413-417
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• 2002

The Internet technology has been recognized not only as a tool far communication in the 21st century but also as an environment for enabling changes in the paradigm of teaching and learning. This paper describes a web-based system development for chemical engineering education. Simulation and visualization of dynamic systems in the environment of a standard web-browser is made possible by extending its capabilities. ActiveX control is used to simulate the system tool far online representation of Virtual Lab. System that is developed using visual basic. The courseware is classified into tutorial, exercises, and virtual experiments.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.269-272
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• 2008

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2000년도 추계심포지움 및 학술발표회:바이오모니터링 기법을 이용한 환경위해성 평가
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• pp.45-45
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• 2000

• 한국환경보건학회지
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• 제44권2호
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• pp.124-132
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• 2018

Objectives: All enterprises intending to install and operate hazardous chemical handling facilities should prepare an off-site risk assessment (ORA) report that evaluates the impact of potential chemical accidents on the surrounding environment and population. This study was conducted to introduce the process of development and the functioning of the Korea Off-site Risk Assessment support tool (KORA) developed by the National Institute of Chemical Safety and to suggest manners to increase its utilization. Additionally, this article provided an overview of KORA. Methods: In order to identify problems with and refinements for KORA, the required items for each phase of KORA were derived by analyzing the Chemical Control Act and related administrative regulations. Results: The functions of KORA made receptor-considered assessment of chemical accidents possible, but several limitations were found in particular phases, such as the analysis of impact range, consideration of sensitive receptors, and assessment of environmental receptors. Conclusion: In this study, we suggested manners to increase the utilization of KORA. It is anticipated that the further research suggested in the study could contribute to the stabilization of the KORA system.

• 한국산업보건학회지
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• 제22권3호
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• pp.191-199
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• 2012

Objectives: The study aim was to evaluate the application of a chemical exposure assessment tool for the Korean workplace. The Ministry of Employment and Labor in Korea (KMOEL) introduced the need for workplace risk assessments in 2011, requiring the Korean chemical industry to consider both domestic and international chemical regulation policies (e.g., estimations of exposure scenarios). Exposure scenarios are required in the European Union as part of material safety data sheets (MSDS) under the Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH) system. Methods: Although many programs for the estimation of exposure have been developed worldwide, to date there is no standard for the Korean workplace. To develop programs suitable for the Korean workplace, we examined the applicability of the European Center for Ecotoxicology and Toxicology of Chemicals target risk assessment (ECETOC TRA), which is recommended by the European Chemical Agency (ECHA). Results: To investigate the applicability of the ECETOC TRA to Korean industry, this study simulated 15 industrial processes. The predicted respiratory exposures for four processes using origin input parameters were underestimated compared to the measured respiratory exposure. Using calibrated input parameters, results for two processes were underestimated compared to the measured respiratory exposure. This result suggests that the use of calibrated input parameters reduces the differences between predicted and measured respiratory exposure. Conclusions: we developed applicable exposure estimating method by modifying the ECETOC TRA program; one suggested the development of exposure estimating program that explains Korea domestic workplace exposure scenario.This study will support the introduction of exposure scenario in MSDS system and protect health of worker from hazardous chemical.

• 한국생산제조학회지
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• 제21권5호
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• pp.848-854
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• 2012

SCM420 steel cutting gear to improve the durability is quenched. When quenching, increases surface hardness, a change of the physical properties and machinability or fall. This study, using a solid carbide hobs skiving hobbing gear cutting finishing. And cutting tool solid carbide TiAlN coating hove when TiAlN coating on the surface of multi-con polishing hob conducted aero lap nano polishing for each cutting. Experimental results conducted aero lap nano coating on the surface polishing tool machinability was excellent. And aero lap nano polishing tool results were reduced 2.5 times the tool wear compared to TiAlN coated tools. Excellent results were 1.42 times longer tool life.

• 한국표면공학회지
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• 제41권2호
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• pp.43-47
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• 2008

Cubic boron nitride(c-BN) films were deposited on tungsten carbide insert tool by microwave plasma enhanced chemical vapor deposition(MPECVD) from a gas mixture of triethyl borate$(B(C_2H_5O)_3)$, ammonia $(NH_3)$, hydrogen$(H_2)$ and argon(Ar). The qualities of deposited thin film were investigated by x-ray diffrac-tion(XRD), field emission scanning electron microscopy(FE-SEM) and micro Raman spectroscope. The surface morphologies of the synthesised BN as well as crystallinity appear to be highly dependent on the flow rate of $B(C_2H_5O)_3$ and $(NH_3)$ gases. The deposited film had more crystallized phases with 5 scem of $B(C_2H_5O)_3$ and $(NH_3)$ gases than with 2 sccm, and the phase was identified as c-BN by micro Raman spectroscope and XRD. The adhesion strength were also increased with increasing flow rates of $B(C_2H_5O)_3$ and $(NH_3)$ gases.