• Corrosion Science and Technology
• /
• v.4 no.1
• /
• pp.29-32
• /
• 2005

A various structural materials are used in construction projects such as a stone, concrete, steel materials. Between of them, concrete are used widely. The compressive strength of concrete is high, and its maintenance and management is comparatively easy. The R.C Building will be superannuated as time passes. This program is generated by propagation of cracks. In order to manage such cracks, time and efforts, expense, etc. are required. In this study, glass sensors were embedding in a model beam and column and leakage of fluorescence and adhesive material was investigated. Further, currents in glass pipe were observed to find the leakage of liquid in glass pipes. Progressive cracks generated by cause the fracture of glass pipes. Therefore, the liquid become to flow and electric current stops, and the cracked part of the member can be found easily. Moreover, the adhesive delays progressive cracking system that responds in air, and the life of a structure can be made to extend. The purpose of this research is to develop of low price sensors that can perform of self-diagnosis in addition to ability of concrete repair concrete to damage.

• Corrosion Science and Technology
• /
• v.15 no.6
• /
• pp.320-325
• /
• 2016

To perform ultrasonic testing (UT) thickness measurement of the secondary side piping installed in nuclear power plants, the insulation for preventing heat loss should be removed. The type of insulation can be divided into fixed and removable insulation. Fixed and removable insulation have their own strengths and weaknesses. Removable insulation has been installed in the components susceptible to wall thinning caused by FAC and erosion from Shin-Kori unit 1, which commenced its commercial operation in 2011. In this paper, the number of repeated inspections of components and the number of replacements of fixed insulation were estimated and a more economical way was identified based on the manufacturing and installation costs for fixed and removable insulation.

• Proceedings of the Korean Society of Marine Engineers Conference
• /
• 2001.05a
• /
• pp.197-201
• /
• 2001

Measuring of the dissolved oxygen is widely used for the environmental control of natural waters, sewage waste treatment, medical and biochemical studies, soil husbandry, food and drug process control, and prevention of corrosion in boilers. Especially, a power plants need special management for preventing accidents from corrosion, therefore, it is essential to measure the concentration of dissolved oxygen in real-time. In this paper we present a method of measuring dissolved oxygen very accurately up to ppb units. This method, called polarographic method, is based on the measures of the electric current generated by the oxidation process in cathode and de-oxidation process in anode, assuming that the amount of the current is proportional to the density of dissolved oxygen.

• Corrosion Science and Technology
• /
• v.10 no.2
• /
• pp.65-70
• /
• 2011

DLC is considered as the candidate material for application of moving parts in automotive components relatively in high pressure and temperature operating conditions for its high hardness with self lubrication and chemical inertness. The properties of interlayer between the substrate and the DLC film were studied. Arc ion plating method have been employed to deposit onto substrate and sputtering method was used for synthesizing DLC onto interlayer. Among these six types of interlayer, deposited DLC film onto TiCN showed excellent value for characteristics. From the results of analysis for physical properties of DLC films, it seems that the adhesion forces were more important factors than intrinsic mechanical properties such as hardness, roughness and wear resistance of DLC films. AFM(Atomic Force Microscope) was used for understanding roughness of DLC films. Hardnesses of the coating layers were identified by nano-indentation method and adhesions were checked by scratch method.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.185-189
• /
• 2008

D.C. traction systems can cause stray currents which could adversely affect both the railway concerned and outside installations, when the return circuit is not sufficiently insulated versus earth. As experience for several decades has not shown evident corrosion effects from a.c. traction systems and actual investigations are not completed, stary currents flowing from a d.c. traction system is issued. D.C. traction systems can cause stray currents can be corrosion and subsequent damage of metallic structures, where stray currents leave the metallic structures. There is also the risk of overheating, arcing and fire and subsequent danger to persons and equipment. Any provision employed to control the effects of stray currents be checked, verified and validated. Direct measurement of stray current is difficult and a provision employed to control the effects of stray currents is proposed.

• Nuclear Engineering and Technology
• /
• v.51 no.5
• /
• pp.1381-1389
• /
• 2019

Stress corrosion cracking (SCC) widely found in both primary and secondary sides of steam generator (SG) tubing in pressurized water reactors (PWR) has become an important safety issue. Using eddy-current tests (ECTs), non-destructive evaluations are performed for the integrity management of SG tubes against intergranular SCC. To enhance the reliability of ECT, this study investigates the effects of oxide films on ECT's detection capabilities for SCC in laboratory-degraded SG tubing in high temperature and high pressure aqueous environment.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.21 no.3
• /
• pp.126-133
• /
• 2013

Recently, it was reported that complaints about problems being experienced with the performance of vehicles operating on autogas in Korea. The problem was being assumed due to contaminants in LPG and an oily material which was being deposited in vaporizer, injector in LPG fuel system. This study is focused on the analysis of contaminant of automobile parts on LPG fuel system. The sampling points of contaminants are injectors, fuel filters, vaporizer in automobile equipment and it was also investigated by GC-MS, ICP-AES, SIMDIS and EDS. According to results, it was presumed that this contaminants had been analyzed plasticizers with hydrocarbons with high boiling point, Fe from steel corrosion, greases from gas station.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2009.05a
• /
• pp.224-224
• /
• 2009

양수발전소의 파이프라인 부식에 대해 연구하였다. 파이프의 파공부위에 대한 외관구조분석, 녹 부위에 대한 SEM, XRD, X선 형광분석 및 모재부와 용접부의 전기화학적 분극을 측정하여 파이프라인의 파공과 부식에 대한 원인을 분석-고찰하고 최적의 관리방안을 제시하고자 하였다.

• Proceedings of KOSOMES biannual meeting
• /
• 2017.11a
• /
• pp.85-85
• /
• 2017

• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.532-534
• /
• 2004

The advancement of electronics and telecommunication technologies has forced the risk management system for underground metallic structures to evolve into the remote monitoring and control system. Especially, facilities such as gas pipelines, oil pipelines and water distribution lines might make hazardous effect on human safety without continuous monitoring and control. As a result, pipeline engineers have applied cathodic protection system to prevent the degradation of their facilities by corrosion and carried out a periodic monitoring of the pipe-to-soil (P/S) potentials at numberous test boxes along their pipelines. The latter action on a road in downtowns, however, is so much dangerous that the inspectors should be ready to suffer the threatening of their lives and maintenance. In order to minimize these social costs and hazards, a stand-alone type corrosion monitoring equipment which can be installed in test box, store the P/S data for given Belied and send the data by wired/wireless telecommunications is under development. In order to obtain the exact P/S data, however, a reference electrode should be located as close to the pipeline as possible. Actually, the measured potential by a conventional portable reference electrode contain inevitably an IR drop portion caused by the current flow from the cathodic protection rectifier or the subway railroad. To minimize this error, it is recommended that the reference electrode should be buried within 10 cm from the pipeline. In this paper, we describe the design parameters for fabricating the permanent type reference electrode and the characteristics of the developed reference electrode.