• Journal of the Korean Society of Safety
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• v.21 no.4 s.76
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• pp.13-18
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• 2006

In spite of frequent defect in industrial boilers, life assessment or diagnostic method for them has not been actively studied. In this research, SS400 carbon steel used in industrial boilers is simulated with artificial aging heat treatment. To do qualitative life assessment, differences in micro-structures and hardness of SS400 by the degradation time are studied. In addition, variation in material properties by aging was observed with the tensile test at room temperature and $179^{\circ}C$ and changes in ductile to brittle transition temperature was observed with the charpy impact test performed at several test temperature.

• Annual Conference of KIPS
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• 2010.04a
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• pp.1055-1057
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• 2010

본 논문은 붕괴 안전을 위한 USN 기반의 안전 계측 시스템에 관한 내용을 수록하고 있다. 붕괴 안전 측정 시스템은 인적 재난의 유형 중 시공 단계에서의 붕괴 안전과 재난 발생을 억제화 하는 목적으로 실시간 계측 장치와 USN의 결합, 실시간 계측 데이터의 정보화, 전송 및 취합된 데이터로부터 붕괴 표준 안전 지수를 도출하는 방법 등으로 구성되어 있다. 본 논문에서는 각 단계별 시스템의 구성요소의 설계와 구현 방법 및 결과의 내용을 중심으로 붕괴 안전 측정을 위한 방법을 제시하고 있으며, 최종적으로는 계측 데이터에 대한 실제 안전지수에 대한 결과 도출로 방재 의사 결정을 지원할 수 있는 의사결정지원시스템의 구현을 목표로 설계하였다.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1365-1367
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• 2011

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.1
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• pp.53-70
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• 2022

Recently, due to the change to SASB(Sustainability Accounting Standards Board) and GRI(Global Reporting Initiative) Standards 2021, the paradigm for non-financial information disclosure is changing significantly, with the number of ESG topics and indicators that must be disclosed by industry from an autonomous material topic selection method. This study revealed that the number of compulsory topics in the oil and gas industry by GRI standards 2021 is up to 2.4 times higher than the average number of material topics disclosed when domestic companies publish sustainability reports using GRI Standards 2020. In the oil and gas industry, I analyzed the similarities and differences between the GRI standards 2021 and the ESG topics covered by SASB by environmental, social, economic, and governance areas. In addition, the materiality test process, which is different in GRI standards 2021, is introduced, and the issues included in the following 10 representative ESG-related initiatives are summarized into 62 and suggested improvement plans for materiality test used in the topic pool.

• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.821-827
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• 2014

An isotope dilution liquid chromatography tandem mass spectrometry (ID LC-MS/MS) method has been developed and applied to the determination of arsenobetaine (AsB, ${(CH_3)_3}^+AsCH_2COO^-$) from oyster candidate certified reference material (CRM). The exact matching isotope dilution approach was adopted for accurate determination of AsB using $^{13}C_2$-labeled AsB as an internal standard. Efficiencies of different AsB extraction methods were evaluated using a codfish reference material and a simple sonication method was selected as the method of choice for the certification of the oyster candidate CRM. The hydrophilic interaction liquid chromatography (HILIC) combined with electrospray ionization tandem mass spectrometry (ESI/MS/MS) in selected reaction monitoring (SRM) mode was optimized for adequate chromatographic retention and robust quantification of AsB from codfish and oyster samples. By analyzing 12 subsamples taken from each 12 bottles systematically selected from the whole oyster CRM batch, the certified value of AsB was determined as $6.60mg{\cdot}kg^{-1}{\pm}0.31mg{\cdot}kg^{-1}$ and it showed excellent between-bottle homogeneity of less than 0.42%, which is represented by relative standard deviation of 12 bottles from the CRM batch. The major source of uncertainty was the certified value of the AsB standard solution.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.2
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• pp.130-137
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• 2016

Non-destructive testing methods for composite materials (e.g., carbon fiber-reinforced and glass fiber-reinforced plastic) have been widely used to detect damage in the overall industry. This study detects defects using optical infrared thermography. The transient heat transport in a solid body is characterized by two dynamic quantities, namely, thermal diffusivity and thermal effusivity. The first quantity describes the speed with thermal energy diffuses through a material, whereas the second one represents a type of thermal inertia. The defect detection rate is increased by utilizing a lock-in method and performing a comparison of the defect detection rates. The comparison is conducted by dividing the irradiation method into reflection and transmission methods and the irradiation time into 50 mHz and 100 mHz. The experimental results show that detecting defects at 50 mHz is easy using the transmission method. This result implies that low-frequency thermal waves penetrate a material deeper than the high-frequency waves.

• Proceedings of the Korean Vacuum Society Conference
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• 1996.02a
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• pp.160-160
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• 1996

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.247-258
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• 2008

Environmental standards for beneficial uses of dredged materials are proposed. Even though chemical analysis of ocean sediments are carried out frequently, their analyses results were not interrelated with the effects of biological lives due to a shortage of biological data. These facts have resulted in difficulty to develope Korean's standards of recycling dredged materials. This paper first searched existing current foreign standards, analyzed local contaminated ocean sediment data, identified their main chemical components of contaminants, and then compared with clean-up standards of sediments consisting of lower and higher levels. From these analysis, new environmental standards considering Korean domestic circumstances are proposed. It is judged that new standards are appropriate to both Korean national sedimental environments and economically recycling aspects because environmental standard levels proposed are higher than background levels of sediments in Korean and foreign standards.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.3
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• pp.253-258
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• 2013

In this paper, a free-space material measurement technique is discussed in W-band(75~110 GHz). For the accurate measurement of S-parameters of an MUT(Material Under Test) in free space, a W-band quasi-optical free-space material measurement system, less affected by the measurement environments, is discussed, and GRL(Gated Reflect Line) method for calibrating the measurement system is described. Proposed technique is verified for 'Air' and measurement results for arystal plates of thickness 1.1 mm, 2 mm, 2.75 mm and 5 mm are also shown.

• Journal of Korean Library and Information Science Society
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• v.25
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• pp.51-82
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• 1996

This study compare and analyzes recent school library standards in advanced countries including Britain, United States and Japan. The examination is based on the changing process of standards and development of school library in the each countries. To Suggest the model of reasonable standard for the activation of school library in Korea, the study has identified the common elements ; staff, material, environments, management and cooperative system, and learning skill with curriculum of school library standards showed in the each of advanced countries.