• Journal of Korea Foundry Society
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• v.15 no.4
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• pp.299-316
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• 1995

• Magazine of the Korea Concrete Institute
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• v.28 no.3
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• pp.74-78
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• 2016

• Magazine of the Korea Concrete Institute
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• v.28 no.4
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• pp.79-84
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• 2016

• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.288-288
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• 2005

• 축산식품과학과 산업
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• v.9 no.2
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• pp.13-17
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• 2020

• Journal of the Korea Institute of Building Construction
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• v.16 no.3
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• pp.229-235
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• 2016

In construction field, it used various technique for concrete formwork. Part of them, non-destructive test has been conducted to estimate a compressive strength of concrete easily such as rebound method and ultrasonic pulse velocity method etc. Former research has recommend proposed equation based on experimental data to investigate strength of concrete but it was sometimes deferent actual value of that from in field because of the few of data in case of early strength concrete. In this study, an experiment was conducted to analyze strength properties for early strength concrete using cylinder mold and $1,000mm{\times}1,000mm{\times}200mm$ rectangular specimen. And compressive strength of concrete was tested by non-destructive test, and calculated by the equation proposed former research. As a result, the non-destructive test results showed approximately 70 percent of the failure test value for all conditions, and worse reliability was obtained for high strength concrete samples when the ultrasonic pulse velocity method was used. Based on the scope of this study, the experimental equation for estimating compressive strength of early strength concrete from 24MPa to 60MPa was proposed.

• Journal of the KSME
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• v.33 no.8
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• pp.717-727
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• 1993

주요국의 보일러 및 압력용기의 기술기준 개발방향이 금속재료기술의 발달, 비파괴검사 기술의 개발, 용접기술의 급진전, 품질요건의 국제적인 규정의 제정 및 준수 등의 현상으로 볼 때 이를 대체적으로 수용하는 ASME Sec. III의 방향으로 통합되어 가는 느낌을 받고 있다. 따라서 우 리나라도 전담기구의 설립 또는 지정을 서둘러 장기적인 안목에서 체계적으로 대처하여야 급격히 변화하는 세계적인 기술흐름에 맞추어 우리의 관련산업이 지속적으로 발전 될 수 있으며 이와 관련된 기술개발방향이 바르게 갈 수 있을 것이다.

• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.5
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• pp.315-320
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• 2006

This paper describes stress analysis and fatigue limit evaluation of plate with V-notch and hole-notch by lock-in infrared thermography. Temperature variation of a specimen under cyclic loading is negatively proportional to the sum of principle stress change and the surface temperature measured by infrared camera is calculated to the stress of notch specimens, based on thermoelastic equation. And also, fatigue limitation can be evaluated by the change of intrinsic energy dissipation. Fatigue limitation of two notch specimens is evaluated as 164 MPa and 185 MPa, respectively and the stress measured by Lock-in infrared Thermography show good agreement within 10% error.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.4
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• pp.371-377
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• 2004

As the turbine running duration in nuclear power plants increases, cracks have been found in the pin finger type blade root area. The nondestructive examination for the blade root area has been carried out by manual ultrasonic examination during the overhaul period, but because of necessity to improve the reliability, we developed an automatic ultrasonic examination system and technique. To demonstrate the performance of the developed automatic ultrasonic examination system, low pressure turbine blades in the 2nd and 3rd stages of nuclear power plants were examined using the developed system. Its applicability nuclear power plant turbine roots of various types was also confirmed.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.4
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• pp.321-329
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• 1998

Structural integrity of nuclear components is important for a safe operation of nuclear power plants. Therefore, nuclear power plants require to perform reliable, periodic inservice inspections. Korea Electric Power Company(KEPCO) operates the entire Korean nuclear power plants. Since nuclear power plant safety and the associated inservice inspection(ISI) are under the plant owner's responsibility, Korea Electric Power Research Institute(KEPRI), the R&D division of KEPCO, has established the ISI NDE Total Support system(TSS) for an efficient performance of ISI tasks, and initiated both key ISI NDE technology development program and traing & qualification system development program for an independent ISI operation. This paper describes details of these programs.