• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.780-785
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• 2016

Heavy oil used as ship propulsion has a serious issue regarding exhaust emission of global warming. Recently, among large-scale merchant ships are using LNG as green ships so called ech-ships. In this study, an vaporizer and pipes under cryogenic and high pressure load were considered to evaluate structural integrity according to codes. Structural analysis of the vaporizer and pipes was performed using the commercial code, ANSYS. Integrity evaluation of the vaporizer based on von Mises stress was performed in accordance with allowable stress specified in ASME Boiler & Pressure Vesssel Section VIII Division 2. To assess structural integrity of the pipes, stress components were combined and compared with ASME B31.3. The calculated stresses for all load cases are lower than allowable stresses, therefore the structural integrity of equipments are verified.

• Journal of the Korean Geosynthetics Society
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• v.14 no.4
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• pp.1-9
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• 2015

According to national regulations and its commentary, such as Rivers Design Criteria & Commentary (KWRA, 2009), Foundation Structure Guideline and its Commentary(MLTM, 2014 and KGS, 2009), the integrity evaluation of river levee includes slope stability evaluation of both riverside/protected low-land and piping stability evaluation with respect to foundation and levee body along with water level conditions. In this case the design hydro-graph can be the most important input factor for the integrity evaluation, however it is fact that the national regulations do not provide any proper determination methods regarding hydro-graph. The authors thus executed an integrity evaluation of sluice gate in levee by changing each hydro-graph factor, including rising ordinary water level, lasting flood water level, falling water level, and flood frequency, in order to suggest a determination method of reasonable hydro-graph. As a result, the authors suggested that at least over 57 hours of rising ordinary water level and over 53 hours of lasting flood water level should be considered for the design hydro-graph of sluice gate in levee at Mun-san-jae.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.4
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• pp.311-320
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• 2014

Rotor blades are important devices that affect the power performance, efficiency of energy conversion, and loading and dynamic stability of wind turbines. Therefore, considering the characteristics of a wind turbine system is important for achieving optimal blade design. When a design is complete, a design evaluation should be performed to verify the structural integrity of the proposed blade in accordance with international standards or guidelines. This paper presents a detailed exposition of the evaluation items and acceptance criteria required for the design certification of wind turbine blades. It also presents design evaluation results for a 2-MW blade (KR40.1b). Analyses of ultimate strength, buckling stability, and tip displacement were performed using FEM, and Miner's rule was applied to evaluate the fatigue life of the blade. The structural integrity of the KR40.1b blade was found to satisfy the design standards.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.315-319
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• 2004

This paper presents the integrity evaluation method of the windings in cast resin transformers using vertical thermal distribution analysis. The method is to compare the temperature distribution in a sound condition specimen with that in the failure condition specimen layer-shorted by accelerated testing. The temperature distribution was acquisited by a infrared thermography system, and the Arrhenius equation was adopted to the accelerated testing. The proposed method may be available to detect the failures in cast resin transformers.

• 한국가스학회:학술대회논문집
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• 1999.09a
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• pp.100-107
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• 1999

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.461-467
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• 2000

This study proposes the integrity evaluation of bogie frame using ultrasonic waves-fractography analysis. Analysis objectives in this study are to investigate fracture planes of damaged zone by the A-scan method. The surface condition of fracture plane shows degree of degradation by stress concentration. The detection of the natural defects in bogie frame is performed using the characteristics of echodynamic pattern in ultrasonic signal. Results of ultrasonic testing agree fairly well with those of actual fracture plane. In quantitative fractography analysis, microstructures of actual fracture plane turned out to be intergranular and transgranular fracture, Proposed ultrasonic-fractography analysis in this study can be used for the integrity evaluation of the bogie frame

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.66 no.1
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• pp.43-47
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• 2017

A SIL(Safety Integrity Level) assignment method is used for preventing failure action. The goal of safety system for processing automation is to reduce the human fatal risk. Even if we have developed the processing automation according to developing technology, we are also realized on increasing the human fatal risk cause of unexpected accidents. This study is directed the solution of decision for safety level for safety system and the best architecture for safety system in process automation.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.529-533
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• 2008

Thick pipes have been used in fields of ocean and industrial plants, and pipe arrangement of oil and water pipelines. Mostly, roll bending process has been used in manufacture of the pipes. Recently, however, studies on the pipe forming processes using brake press have been performed. Normally, the brake press has high aspect ratio, so structural integrity evaluation should be conducted. In this study, finite element analysis of structural integrity for the brake bending press was carried out for thick pipe forming process.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.459-464
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• 2001

For major nuclear power plant components periodic inspections and integrity assessments are needed for the safety. But many flaws are undetectable due to sampling inspection. Probabilistic integrity assessment is applied to take into consideration of uncertainty and variance of input parameters arise due to material properties, applied load and undetectable flaws. This paper describes a Probabilistic Fracture Mechanics(PFM) analysis based on Monte Carlo(MC) algorithms. Taking important parameters as probabilistic variables such as fracture toughness, crack growth rate and flaw shape, failure probability of major nuclear power plant components is archived as a results of MC simulation. For the verification of these analysis, a comparison study of the PFM analysis using other commercial code, mathematical method is carried out and a good agreement was observed between those results.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.91-92
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• 2016

Structural integrity of reinforced concrete structures including nuclear power plants needs to be evaluated on a regular basis. Deterioration inside the concrete structures can be represented by voids. In this study, the varied volume fraction of voids inside mortar specimens was studied as a parameter using ultrasonic testing equipments. Both direct and indirect measurement methods were employed. The results show that there is a clear distinction between the specimens with different void volume fractions.