• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.343-344
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• 2018

This study proposes a standard method of diagnosis and repair to prevent and maintain the problem of durability deterioration caused by leakage cracks in apartment basement structures in Korea. Following the announcement of the previous maintenance plan section, this is the second part of the study, focusing on inspection of methods for diagnosing and repairing leakage cracks in apartment basement structures. In this thesis, the matters required for the procedures, types, times and equipment of the inspection plan and the inspection methods, records, and decisions required for the actual inspection are described.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.6
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• pp.521-526
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• 2010

Gas transmission pipelines are often inspected and monitored using the magnetic flux leakage method. An inspection vehicle known as a "pig" is launched into the pipeline and conveyed along the pipe by the pressure of natural gas. The pig contains a magnetizer, an array of sensors and a microprocessor-based data acquisition system for logging data. This paper describes magnetic flux leakage (MFL) signal processing used for detecting mechanical damages during an in-line inspection. The overall approach employs noise removal and clustering technique. The proposed method is computationally efficient and can easily be implemented. Results are presented and verified by field tests from an application of the signal processing.

• Journal of Industrial Technology
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• v.18
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• pp.453-460
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• 1998

The purpose of this study was to analyze their status of underground storage tank(UST) facilities and level of soil contamination, and to establish its management criteria. DB program was developed to analyze the correlation between specific characteristic of UST and level of soil contamination. For a suitable management of UST, leakage monitoring and inspection method of UST was investigated. Inspection period was established based on the leakage rate. The most dominant factor for leakage seemed to be caused by the corrosion. Therefore, main factor, construction method and installation year of UST, and corrosion protection system were suggested for optimal protection of UST. Considering the present management status of UST in Korea, inspection and management criteria of UST should be accomplished in term of contamination protection of leakage, and flexible regulation act should be introduced for each specific site.

• Journal of the Korean Institute of Gas
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• v.27 no.3
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• pp.72-76
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• 2023

Among urban gas-using facilities, more and more cases are using gas meters for leakage inspection instead of inspection ports for concealment pipes. Leak alarm alarms were continuously generated according to the boiler's special usage pattern in an environment where there was no actual gas leakage among some households where this meter was installed. It does not perform its original function of detecting actual gas leakage. Based on these problems, this study analyzed the conditions under which the gas meter for leakage inspection generates leakage alarms according to the boiler's special gas use pattern, and sought a set value that can generate an alarm only in the case of actual gas leakage. Through this, it is intended to relieve citizens' anxiety about gas use due to malfunction of the alarm and at the same time perform the original function of the meter that can detect leaking gas.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.1
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• pp.142-147
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• 2018

Private electrical facilities are judged whether it is suitable for the insulation aging condition of their incoming underground cables using DC leakage current test method. In the case where the service point of utility is the secondary side of cut out switch installed in the electric pole, there is a problem that it is difficult to separate the lightning arresters(LA) because of their high position of the pole. Therefore, the field test voltage is applied at value lower than DC 30 kV, which are stated in the inspection guideline. However, this test could reduced the insulation performance of the LA by accelerating the electrical stress of the metal oxide varistor element in the pre-breakdown region. In this study, we analyzed the relationship between the DC test voltage and the leakage current using the non-destructive DC high voltage equipment with leakage current measurement function. The results show that the leakage current increases sharply above the specified test voltage. As a consequence, it could be contributed to improve insulation aging inspection method by selecting the possible test area on the VI characteristic curve of the pre-breakdown area of the LA.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.4
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• pp.402-409
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• 2013

An innovative application of voltage-contrast (VC) inspection allowed inline detection of NMOS leakage in dense SRAM cells is presented. Cell sizes of SRAM are continual to do the shrinkage with bit density promotion as semiconductor technology advanced, but the resulting challenges include not only development of smaller-scale devices, but also intra-devices isolation. The NMOS leakage caused by the underneath n+/P-well shorted to the adjacent PMOS/N-well was inspected by the proposed electron-beam (e-beam) scan in which VC images were compared during the in-line process step of post contact tungsten (W) CMP (Chemical Mechanical Planarization) instead of end-of-line electrical test, which has a long response time. A series of experiments based on the mechanism for improving the intra-well isolation was performed and verified by the inline VC inspection. An optimal process-integration condition involved to the tradeoff between the implant dosage and photo CD was carried out.

• Journal of Sensor Science and Technology
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• v.15 no.5
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• pp.328-333
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• 2006

Magnetic Flux Leakage (MFL) methods are widely employed for the nondestructive evaluation (NDE) of gas pipelines. In the application of MFL pipeline inspection technology, corrosion anomalies are detected and identified via their leakage filed due to changes in wall thickness. The gas industry is keenly interested in automating the interpretation process, because a large amount of data to be analyzed is generated for in-line inspection. This paper presents a novel approach to the tasks of data segmentation, feature extraction and depth estimation from gas pipelines. Also, we will show that the proposed method successfully identifying artificial defects.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.237-238
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• 2019

As part of the development of building technology to improve the living performance closely related with lifestyle to Realize the Housing Welfare, the standard manual for the prevention and maintenance of water leaks in the underground structures of apartment buildings consists of Part 1 and Part 2. This study further covered the maintenance plan and inspection carried out in Part 1.

• Journal of Power System Engineering
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• v.15 no.1
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• pp.18-23
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• 2011

Image processing has provided powerful techniques to extract from the acoustic signals the desired information on evaluation for leakage existence, leakage rate, and searching for leakage location, etc. The imagery NDE data available can add additional and significant dimension in nondestructive evaluation(NDE) information and thus for exploiting in applications. To extract such information the use of advanced image processing techniques is much needed. In recent years, there has been much increased use of acoustic signal image processing techniques in acoustic NDE. This approach will increase the efficiency of inspection procedures and reduce inspection time. In this paper we are concerned only with This paper is concerned mainly with the use of advanced image processing techniques in valve leakage detection and advanced image restoration and enhancement methods, which attempt to evaluate promptly by a visualization method the acoustic sources while detecting the valve leakage.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.6
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• pp.21-31
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• 2018

The result of examination of diagnostic method, which is composed of a combination of a thermal camera and a drone that visually shows the temperature of the object by detecting the infrared rays, for detecting the leakage of earth dam was driven in this research. The drone infrared thermography method was suggested to precise safety diagnosis through direct comparing the two method results of electrical resistivity survey and thermal image survey. The important advantage of the thermal leakage detection method was the simplicity of the application, the quickness of the results, and the effectiveness of the work in combination with the existing diagnosis method.