• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.4 no.2
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• pp.46-49
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• 2008

NDE(Nondestructive examination) detects a flaw or discontinuity in materials. Flaws detected by the pre-service or in-service examinations shall be sized for the purpose of analysis and repair. A flaw that is initiated from the surface is difficult to determine its depth by NDE. The depth of the surface flaw can be measured using an ultrasonic diffracted wave. To find the optimum standard for ultrasonic parameter(For example, frequency & size of transducer), a mock-up test and simulation were established and studied. This inspection technology may show the depth sizing possibility of the flaw down to nearly two(2) mm.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2761-2763
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• 2002

원자력발전소에서는 건설완료 단계에서 기기, 배관 및 각종 지지구조물에 대하여 PSI(Pre-Service Inspection)를 실시하여 시공된 설비의 건전성을 점검하고, 운영중에는 주기적으로 시간의 경과에 따른 취약화 정도를 비과괴검사로 감시 및 평가하는 ISI (In-Service Inspection)를 실시하여 안전성 관련 설비의 건전성을 점검하고 있다. 이 과정에서 방대한 양의 검사데이터가 생산되며 원전 가동년수가 증가함에 따라 검사자원을 체계적으로 관리하고 자동화 할 수 있는 시스템 개발이 필요하게 되었다. 본 논문에서는 PSI/ISI 검사결과 정보관리를 비롯하여 검사 기초자료 관리 및 검사계획 수립, 파괴역학 분식 기능 등을 포함한 Web 기반의 Application 개발 사례를 소개한다. 또한 가상현실 기법을 적용하여 기존의 2차원적 DB 운영을 3차원 가상공간에서 운영할 수 있는 'Touch & Tell' 기법을 개발하고 그 구현방법을 제시한다.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.439-444
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• 2012

Photovoltaic energy is regarded as the key solution to the instability of energy supply and environmental pollution, and it is spreading from the developed countries to world wide. This paper looks into guide lines of KESCO (Korea electrical Safety Corporation) on Photovoltaic system and analyzed case of inconsistencies of pre-service inspection. Through these analyses it will be possible to prevent possible accidents in the process of installing Photovoltaic system and thus ensure electrical safety of Photovoltaic system.

• Journal of the Korean Society for Nondestructive Testing
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• v.17 no.2
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• pp.108-113
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• 1997

Ultrasonic testing is one of the most widely used method of nondestructive testing for pre-service inspection(PSI) & in-service inspection(ISI) in structures of bridges, power plants, chemical plants & heavy industrial fields. It is very important to estimate safety, life, quality of structures. Also, a lot of research for quantities evaluation & analyses inspection data is proceeding. But traditional portable ultrasonic flaw detector had been following disadvantages. 1) Analog ultrasonic flaw detector decreased credibility of ultrasonic test, because it is impossible for saving data & digital signal processing. 2) Stand-alone digital ultrasonic flaw detector cannot effectively evaluate received signals because of lack of its storage memory. To overcome this shortcoming, we develop the computer based ultrasonic flaw detector for nondestructive testing. It can store the received signal and effectively evaluate the signal, and then enhance the reliability of the testing results.

• Korea Journal of Hospital Management
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• v.24 no.1
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• pp.11-20
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• 2019

The purpose of this study was to identify the factors affecting the use of superior general hospitals on public holidays by using the medical use model (Dutton's medical use model) with the medical panel data. The study found that 34.2% of superior general hospital emergency rooms were used on public holidays and the factors which made statistically significant influences on the use of superior general hospital emergency rooms on public holidays were whether patients were operated or emergency care and inspection etc. Also, there was a difference depending on whether the type of establishment of the medical insititution is national or private. In other words, patients who received emergency care and examinations were found to make more frequent visit to hospital emergency room on pubic holiday, compared to patients who underwent surgery and those who visited emergency rooms in the private superior general hospital did so, compared to those who visited emergency room in the national general hospital(OR, 4.4, 3.386, respectively). Therefore, it is necessary to consider the introduction of integrated care of health and social care medical service that focuses on primary care in Denmark, which focuses on patients, and pre-The Canadian Triage and Acuity Scale(pre-CTAS) in the UK.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.4
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• pp.313-320
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• 1998

To record and evaluate the flaws which were found during pre-service/in-service inspection performance of nuclear power plants in Korea, the center line beam method described in ASME code and 6 dB drop method stated in CSA code were used. The measured through wall dimensions and lengths by these methods were compared and analyzed in this report. With the measured data analysis, the ekact understanding and use of these methods improves the reliability of flaw sizing and assures the integrity of nuclear power plant components.

• Korean Journal of Materials Research
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• v.13 no.10
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• pp.651-657
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• 2003

Ultrasonic microscope has been used to detect the defects on surface or inner solid. Conventionally, it has used at a single operating frequency. The resolution and quality of the measured images are determined by a characteristic of the transducer of the ultrasonic microscope. The conventional ultrasonic microscope has been used envelope detector to detect the amplitude of reflected signal, but the changes in amplitude is not sensitive enough for specimen with microstructure that in phase. In this paper, we have studied multi-frequency depth resolution enhancement with ultrasonic reflection microscope for the reflectors of a stainless steel reference specimen and a reference calibration block to be used as the material in nuclear power plants for ISI, PSI. Increased depth resolution can be obtained by taking two, three-dimensional images at more that one frequency and numerically combining the results. As results of the experiment, we could get enhanced images with the rate of contrast in proportion and high quality signal distribution for the image to the changing rate of depth for the reflectors of the two kinds of specimens.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.3
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• pp.200-205
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• 2000

In a previous paper, we have discussed the intelligent Windows 95-based data management program(IDPIN) which was developed for effective and efficient management of large amounts of pre-/in-service inspection(PSI/ISI) data of Kori nuclear power plants. The IDPIN program enables the prompt extraction of previously conducted PSI/ISI conditions and results so that the time-consuming data management, painstaking data processing and analysis of the past are avoided. In this study, the intelligent Windows based data management program(WS-IDPIN) has been developed as an effective data management of PSI/ISI data for the Wolsong nuclear power plants. The WS-IDPIN program includes the modules of comprehensive management and analysis of PSI/ISI results, statistical reliability assessment program of PSI/ISI results(depth and length sizing performance etc), standardization of UT report form and computerization of UT results. In addition, the program can be further developed as a unique PSI/ISI data management expert system which can be part of the PSI/ISI total support system for Korean nuclear power plants.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.469-472
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• 2008

In general, structures in service gradually lose original performance according to time due to initial defects in design and construction, or exposure to unfavorable external conditions such as repeated loading or deteriorating environment, and in extreme cases, may collapse in large disaster. Therefore, in order to maintain the serviceability of structures at optimal level, advanced structure measuring system which can inform optimal time point and method of maintenance is required in addition to accurate prediction of residual life the structure by periodic inspection. To guarantee the safety level of bridge structure and to prevent from disaster, the integration of safety network for bridge structures are needed. Therefore in this study, to enhance the effectiveness of safety network for bridge, the connection methodologies between safety network and pre-installed bridge monitoring system are investigated.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.3
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• pp.256-263
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• 2009

After several PWSCCs were found in Bugey(France), Ringhals(Sweden), Tihange(Belgium), Oconee, Arkansas, Crystal Fever, Davis-Basse, VC Summer(U.S.A.), Thuruga(Japan), USNRC and PNNL started the research on PWSCC, that is, the PINC project. USNRC required KINS to participate in the PINC project in May 2005. KINS organized the Korean consortium at March 2006 and Pre-RRT for RVHP were performed for the preparation of PINC RRT. Through these preliminary RRT, Korea NDE teams can learn and develop the detection and sizing technique for RVHP dissimilar metal weld. These techniques are now being prepared in Korea and need to be utilized for the In-service inspection of the RVHP and BMI of Korea Nuclear Power Plants. PINC RRT mock-ups will be helpful to training.