• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.659-662
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• 2005

Electrochemical impedance spectroscopy (EIS) has been extensively used to try to evaluate the corrosion state of the steel/concrete system. This technique is attractive because, in theory, used in a wide range of frequencies, it can give detailed information about the mechanisms and kinetics of the electrochemical reactions. Impedance measurements were performed using potential control and measuring the corresponding current response. One-year-old southern exposure test. specimens were used in the current study. The effectiveness of corrosion inhibiting additives was evaluated. The corrosion current densities estimated by impedance measurements were confirmed by those determined using linear polarization techniques. The purpose of this study was to evaluate the long-term-performance potential of the corrosion inhibitors in chloride contaminated reinforce concrete.

• Transactions of the Korean hydrogen and new energy society
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• v.8 no.1
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• pp.31-41
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• 1997

In order to investigate the mechanism of electrochemical hydrogenation reaction on Zr-based Laves phase hydrogen storage alloy electrodes, electrochemical charge/discharge characteristics, potentiostatic/dynamic polarizations and electrocehmical impedance spectroscopy(EIS) of Zr-Ti-Mn-Ni and Zr-Ti-Mn-Ni-M(M=Fe, Co, Al) alloys were examined. Electrochemical discharge capacities of the alloys were quite different with gas charge capacities. Therefore, it was considered that discharge capacities of the alloys depend on electrochemical kinetic factors rather then thermodynamic ones. Discharge efficiencies were increased linearly with exchange current densities. The results of potentiostatic/dynamic polarization measurements showed that electrochemical charge and discharge reaction of Zr-based Laves phase hydrogen storage alloys is controlled by charge transfer process at the electrode surface. The EIS measurements also confirmed this result.

• Journal of Environmental Impact Assessment
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• v.5 no.1
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• pp.1-13
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• 1996

This paper examined public participation in the final Environmental Impact Statement(EIS) in terms of institutional procedures and content analysis. By reviewing EIS Draft Manual and related laws and regulations, seven problems were identified in the system. The content of public participation in 14 EISs were analyzed by a developed protocol, most results of which were similar to the identified seven problems. In conclusion, this paper suggested that the systematic problems should be improved to activate more efficient public participation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.134-135
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• 2016

To evaluate anti-corrosion performance of rebar in concrete according to the amount of chloride and inhibitor, electrochemical impedance spectroscopy(EIS) method was conducted in this study. For the anti-corrosion performance evaluation according to time, Impedance of rebar in concrete was measured before and after 5 cycle of corrosion acceleration. As a results, The impedance of rebar in concrete added chloride decreased than before corrosion acceleration. However impedance of other specimens was maintained or increased than before corrosion acceleration.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10a
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• pp.466-468
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• 2000

J2EE(JavaTM 2 Platform, Enterprise Edition)의 클라이언트 애플리케이션, 웹 컴포넌트, Enterprise JavaBeans 컴포넌트와 같은 앤터프라이즈 애플리케이션은 개발된 후 컨테이너에 배치되어 실행된다. 이러한 앤터프라이즈 애플리케이션(enterprise application)은 다양한 EIS(Enterprise Information System)에 접근하여 관련된 기능과 데이터를 사용할 필요가 있다. J2EE 커넥터 아키텍처(Connector Architecture)는 J2EE 플랫폼을 다양한 EIS와 연결하기 위한 표준을 정의하는 API 이며, 각 EIS 벤더는 이러한 커넥터 아키텍처의 설계서를 따르는 EISF의 시스템 레벨 소프트웨어 드라이버인 표준 리소스 어댑터(Resource Adaptor)를 제공한다. 커넥터 아키텍처를 구현한 리소스 어댑터를 사용함으로써 특정 벤더의 J2EE 플랫폼에 종속되지 않도록 EIS를 통합할 수 있다. 본 논문에서는 이러한 J2EE 커넥터 아키텍처를 구현한 리소스 어댑터를 애플리케이션 서버를 배치하기 위하여 배치기가 수행해야 하는 배치 단계를 크게 네 단계로 구분하고, 배치구성 활동을 다섯 가지로 분류 및 정의한다,

• Journal of Korea Society of Industrial Information Systems
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• v.1 no.1
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• pp.301-321
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• 1996

EIS는 최고 경영자의 정보 욕구를 중촉키 위해 급격히 부상하고 있는 MIs의 한 서브시스템이다. 기업의 정보화추세와 정보기술활용의 저변확대로 말미암아 컴퓨터이 직접적인 혜택과는 그간 거리가 멀었던 기업의 중역들도 단말기 앞에 앉을 수 밖에 없게 되었다. 본 사례연구는 H사의 EIS구축 사례를 소개하고자 한다. 현재, 1차 개발이 완료되어 시험가동을 하고 있다. 그 성과를 자체 분석한 결과는 다소 실망적인 것이어서 2차 개발계획을 수립하여 추진 중에 있다. 1차 개발의 실패는 추후 보다 나은 EIS의 구축을 위해서 많은 교훈을 던져주고 있다. 따라서 본 논문에서는 1차적으로 개발된 시스템이 특성과 그것의 문제점을 찾는데 초점을 맞추었으며, 2차 개발의 방향도 아울러 소개하고자한다.

• Corrosion Science and Technology
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• v.16 no.4
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• pp.167-174
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• 2017

Bicarbonate/carbonate and molybdate anions have been characterized for their inhibitive effect on pitting corrosion of carbon steel in simulated concrete pore solution by using electrochemical tests such as electrochemical impedance (EIS) and linear polarization (LP). It was revealed that bicarbonate/carbonate has a weak inhibitive effect on pitting corrosion that is approximately one order of magnitude lower compared to hydroxide. Molybdate is effective against pitting corrosion induced by the concentration of chloride as low as 113 mM and can increase the pitting potential of a previously pitted sample to the oxygen evolution potential by the concentration of molybdate as much as 14.6 mM only. The formation of a $CaMoO_4$ film on the surface hinders the reduction of dissolved oxygen on the steel surface, reducing corrosion potential and increasing the safety margin between corrosion potential and pitting potential further. In addition, pore-plugging by $FeMoO_4$ as a type of salt film within pits increases the likelihood of repassivation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.38-39
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• 2014

In this research, the evaluation method of segregation resistance is suggested using the ratio of maximum and minimum values of concrete slump flow. As a result, in the case of normal concrete range from 80 to 210 mm of slump, it is considered that managing the EIS-N value to less than 1.10 is the most favorable for segregation determination.

• Corrosion Science and Technology
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• v.15 no.1
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• pp.1-5
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• 2016

Zinc ethyl silicate coatings containing multi walled carbon nanotubes (MWCNTs) were prepared, to which we added spherical and flake shaped zinc particles. The anti-corrosive effects of MWCNTs and zinc shapes on the zinc ethyl silicate coated carbon steel was examined, using electrochemical impedance spectroscopy and corrosion potential measurement. The results of EIS and corrosion potential measurement showed that the zinc ethyl silicate coated with flake shaped zinc particles and MWCNT showed lesser protection to corrosion. These outcomes were in agreement with previous results of corrosion potential and corrosion occurrence.

• Corrosion Science and Technology
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• v.15 no.1
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• pp.13-17
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• 2016

The aim of this study was to evaluate the use of iron-nickel oxide ($Fe_2O_3$.NiO) nanopowder (FeNi) as an anti-corrosion pigment for a different application. The corrosion protection ability and the mechanism involved was determined using aqueous solution of FeNi prepared in a corrosive solution containing 3.5 wt.% NaCl. Anti-corrosion abilities of aqueous solution were determined using electrochemical impedance spectroscopy (EIS) on line pipe steel (API 5L X-80). The protection mechanism involved the adsorption of metallic cations on the steel surface forming a protective film. Analysis of EIS spectra revealed that corrosion inhibition occurred at low concentration, whereas higher concentration of aqueous solution produced induction behavior.