• Proceedings of the CALSEC Conference
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• 1999.07a
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• pp.123-132
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• 1999

시스템이 GIGO를 넘어 자기검증성을 갖추려면 - 체계적 Reporting - 예외분석 및 검증논리 (업무 + IT 모두) - 업무시스템과 정보시스템의 문서화(중략)

• Journal of Electrochemical Science and Technology
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• v.4 no.2
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• pp.47-56
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• 2013

Inhibition performance of Lornoxicam & Tenoxicam against corrosion of carbon steel in 1M $H_2SO_4$ solutions was investigated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The inhibition efficiency increased with increasing inhibitor's concentration, but decreased with increase in temperature. Potentiodynamic polarization curves showed that, the inhibitors were of mixed type. The apparent activation energy ($E^*_a$) and other thermodynamic parameters for the corrosion process have also been calculated and discussed. The inhibition of carbon steel corrosion is due to the adsorption of the inhibitor molecules on the surface, which follows Temkin adsorption isotherm. The mechanism of inhibition was discussed in the light of the chemical structure of the undertaken inhibitors.

• Journal of Electrochemical Science and Technology
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• v.4 no.2
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• pp.61-70
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• 2013

Corrosion inhibition of carbon steel in 2M HCl by some benzohydrazide derivatives (I-III) was studied using weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) techniques at $30^{\circ}C$. Polarization studies showed that all the investigated compounds are of mixed type inhibitors. Temperature studies revealed a decrease in efficiency with rise in temperature and corrosion activation energies increased in the presence of the hydrazide derivatives, probably implying that physical adsorption of cationic species may be responsible for the observed inhibition behavior. Electrochemical impedance studies showed that the presence of benzohydrazide derivatives decreases the double layer capacitance and increases the charge transfer resistance. The adsorption of these compounds on carbon steel surface was found to obey Temkin's adsorption isotherm. Synergistic effects increased the inhibition efficiency in the presence of halide additives namely KI and KBr. An inhibition mechanism was proposed in terms of strongly adsorption of inhibitor molecules on carbon steel surface.

• Journal of the Korean Chemical Society
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• v.58 no.2
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• pp.160-168
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• 2014

The electrochemical behavior and corrosion inhibition of zinc in 0.5 M $H_2SO_4$ in the absence and presence of some chromones has been investigated using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. The presence of these investigated compounds in the corrosive solutions decrease the weight loss, the corrosion current density, and double layer capacitance but increases the charge transfer resistance. Polarization studies were carried out at room temperature, and showed that all the studied compounds act as mixed type inhibitors with a slight predominance of cathodic character. The effect of temperature on corrosion inhibition has been studied and the thermodynamic activation and adsorption parameters were determined and discussed. The adsorption of the investigated compounds on zinc was found to obey Langmuir adsorption isotherm.

• Corrosion Science and Technology
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• v.5 no.2
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• pp.62-68
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• 2006

Solvent free high solid coatings are increasingly used as they posses number of advantages such as, lower cost per unit film thickness, better performance and eco-friendliness. In the present study polymeric film-forming materials such as aniline-novolac (ANS), cresol-novolac (CNS) and acrylic copolymer blended cresol-novolac (ACNS) coating materials have been prepared. The corrosion resistance properties of the prepared high solid coating materials have been evaluated through potential-time, potentiodynamic polarization and electrochemical impedance studies (EIS). Among the three coating systems, cresol-novolac polymer coated substrates offer better corrosion resistance property and the order of the performance was found as CNS > ACNS > ANS. We can recommend these systems for use in automobile applications.

• Proceedings of the KIPE Conference
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• 2013.11a
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• pp.11-12
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• 2013

In this research, a novel multi-converter system for the fuel cell diagnostics and the load leveling function under varying load condition is proposed. The proposed system is composed of two converters and operates in two different modes. In the normal mode operation the additional bidirectional converter is used for the load leveling and in the diagnostic mode it is used for implementing integral diagnostics by way of electrochemical impedance spectroscopy (EIS). The proposed method can perform the EIS for fuel cell under varying load conditions with no influence to the load. The validity and feasibility of the proposed system is verified by the experiments and the design procedure of the proposed system is detailed.

• Journal of Ocean Engineering and Technology
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• v.17 no.6
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• pp.77-82
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• 2003

The absorption of water into an anti-corrosive organic coating, such as alkyd and urethane resin coating, was investigated, using a quartz crystal microbalance (QCM). Anticorrosive properties of the coatings were also measured, by means of electrochemical impedance spectroscopy (EIS). The overall absorption of water in the coating is determined by the chemical nature of resin, and decreases with increasing thickness. The enhancement of anti-corrosive performance, through increase of coating thickness, was more remarkable in the case of the coating that hadlower equilibrium water absorption. The absorption kinetics curves were Fickian in nature. The EIS analysis confirmed that the resin, having lower equilibrium water absorption, shows higher anti-corrosive performan.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.157-160
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• 2007

The catalyst layer of a proton exchange membrane (PEM) fuel cell is a mixture of polymer, carbon, and platinum. The characteristics of the catalyst layer play critical role in determining the performance of the PEM fuel cell. This research investigates the role of catalyst layer composition using a Central Composite Design (CCD) experiment with two factors which are Nafion content and carbon loading while the platinum catalyst surface area is held constant. For each catalyst layer composition， polarization curves are measured to evaluate cell performance at common operating conditions, Electrochemical Impedance Spectroscopy (EIS), and Cyclic Voltammetry (CV) are then applied to investigate the cause of the observed variations in performance. The results show that both Nafion and carbon content significantly affect MEA performance. The ohmic resistance and active catalyst area of the cell do not correlate with catalyst layer composition, and observed variations in the cell resistance and active catalyst area produced changes in performance that were not significant relative to compositions of catalyst layers.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.09a
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• pp.59-69
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• 1995

본 연구에서는 포항제철의 사례를 바탕으로 사용중인 중역정보시스템(EIS: Executive Information System. 이하 "EIS"라함)을 보다 효과적으로 개선하 기 위한 새로운 방법을 소개한다. 제시되는 전략적 분석 모델은 중역, 정보 제공 책임자, 비서진, 기존의 소프트웨어 트래킹을 주요 정보 제공원으로 하 며 단계를 결정한다. 각 단계에서는 과거 정보요구분석을 실시한 방법들의 효과성을 평가하고 새로운 방법들을 제시한다. EIS가 개발 의도와는 달리 사 용 빈도는 줄어들고 있는 추세를 보이는 경우가 많아 올바른 정보요구 도출 방법이 요구되고 있다. 사용자인 중역으로부터 정보요구를 잘 도출할 수 있 는 방법들이 적용 상에 많은 어려움을 보이고 있고 이에 대한 연구가 중요 함에도 불구하고 관련 연구가 부족한 형편이다. 그러므로 본 연구는 EIS의 개발 또는 개선의 경우에 있어서 중역의 정보요구사항을 명확히 정립하는데 도움을 줄 수 있을 것이다. 수 있을 것이다.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.581-584
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• 2007

RTE(Real Time Enterprise)라는 경영 기법이 21 세기에 대두 되면서 많은 기업들이 환경을 구축하기 시작 하고, 보험사들도 ERP 구축을 통하여 RTE 환경을 이루고자 노력하고 있다. 본 논문에서는 한국 보험사에 구축된 사례를 바탕으로 관리 회계 관점에서의 ERP 와 Legacy 시스템간의 인터페이스를 분석하였다. 이를 통해 유지 보수 단계의 문제점과 시스템 자원 이용의 비효율성 및 시스템 확장에 대한 요구 사항을 쉽게 수용 할 수 없는 구조로 구축 되었음을 알 수 있었다. 이에 대한 해결책으로써 Data Hub 신설 및 코드 항목의 독립 등을 포함한 효과적인 모델을 제시 하며, 그 결과로Disk 이용을 26 % 절약 하고, 유지 보수의 용이성 및 시스템 확정의 용이성을 확보 할 수 있다.