• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.492-500
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• 2004

The purpose of this study is localization of safety relief valves fur Nuclear Service through technical development with overall design, fabrication, inspection, capacity certification test and functional qualification test of safety relief valves in accordance with KEPIC MN Code(or ASME Sec.III ). The safely relief valve is the important equipment used to protect the pressure vessel, the steam generator and the other pressure facility from overpressure by discharging the operating medium when the pressure of system is reaching the design pressure of the system. But we're depending on technology of the other country up to the present time. Because we don't have our own technologies, we have been spent the great time and money on installing and repairing safety relief valve at nuclear power plant. Therefore we have to achieve the development of safety relief valves for Nuclear Service with our own technologies.

• Journal of Applied Reliability
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• v.17 no.1
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• pp.66-71
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• 2017

Purpose: Polymer capacitors are known to have very high reliability as compared with liquid electrolytic capacitors, but their capacity has been reported to decrease in charge and discharge at low temperature. The purpose of this study to clarify these characteristics. Methods: In order to clarify these characteristics, charging-discharging tests were carried out for 200 hours with three different capacities and at 5 different temperature from $5^{\circ}C$ to $100^{\circ}C$. Results: As a result of the test, it was confirmed that the capacity of the polymer capacitor was decreased with higher capacity and lower temperature. Conclusion: Such a failure phenomenon was caused by the shrinkage and expansion characteristics of the polymer used therein, it is presumed that this failure phenomenon is due to the complex pore structure made by etching.

• New & Renewable Energy
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• v.19 no.4
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• pp.72-83
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• 2023

Only ground source heat pump units certified according to the regulations in Korea can be adopted in ground source heat pump systems. In this study, domestic and international standards and regulations for ground source heat pump units were investigated. Unlike ISO 13256-1~2, which is the international standard, KS B 8292~8294 for ground source heat pump unit only included rated test conditions. Therefore, it is necessary to supplement various test conditions to the KS B series, because its performance data, which is required to calculate the system's design capacity, is dependent on the change in entering water temperature. The difference between the coefficient of performance of the certified ground source heat pump units and the certified criteria changed significantly according to the operating mode, heat source, and load type, because the criteria increased by about 5% for all. Thus, it is highly suggested that the certification standards be revised while considering the product performance level and various conditions.

• The KSFM Journal of Fluid Machinery
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• v.8 no.3 s.30
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• pp.16-25
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• 2005

The purpose of this study is localization of safety relief valves for Nuclear Service. The safety relief valve is the important equipment used to protect the pressure vessel, the steam generator and the other pressure facility from overpressure by discharging the operating medium when the pressure of system is reaching the design pressure of the system. We developed design technology used FEM ' CFM about safety relief valve for Nuclear Service according to ASME (or KEPIC) Code and KHNP's Technical Specification. To prove validity of a design technology, actually, we manufactured and inspected and tested the sample products designed according to a developed technology. The capacity qualification test was achieved according to requirement of ASME(or KEPIC) Code by NBBI and the functional qualification test was achieved according to ASME QME-1 for operating condition in technical specification of KHNP by NLI. Therefore we have to achieve the development of safety relief valves for Nuclear Service with our own technologies.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.203-206
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• 2005

The objective of study on composite cylinder for alternative fuel vehicle is to develop safe, efficient, and commercially viable, on-board fuel storage system for the fuel cell vehicle or natural gas vehicle that use highly compressed gaseous fuel such as hydrogen or natural gas. This study presents the whole procedure of development and certification of a type 3 composite cylinder of 207bar service pressure and 70 liter water capacity, which includes design/analysis, processing of filament winding, and validation through various testing and evaluation. Design methods of liner configuration and winding patterns are presented. Three dimensional, nonlinear finite element analysis techniques are used to predict burst pressure and failure mode. Design and analysis techniques are verified through burst and cycling tests. The full qualification test methods and results for validation and certification are presented.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.349-352
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• 2007

A GFRP based composite blade was developed for a 2MW wind energy conversion system of type class IIA. The blade sectional geometry was designed to have a general shell-spar and shear web structure. The load cases specified in the IEC61400-1 international specification were considered. For withstanding all relevant extreme loads, the structural analysis for the complete blade was performed using a commercial FEM code. The static load carrying capacity, blade tip deflection and natural frequencies were evaluated to satisfy the strength and stability requirements in accordance with the IEC61400-1 and GL Regulations. The prototype blade was passed the structural proof test for GL certification.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.4
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• pp.269-282
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• 2017

Objectives: Currently, masks against yellow dust and fine particulates are being certified with no consideration of facial dimensional variations among children and adults. The aims of this study were to develop masks against yellow dust and fine particulates for children in Korea and provide basic data to suggest new test methods for mask certification that consider the breathing capacity of children. Methods: A total of 730 study participants aged from six to 13 years old were recruited in the Seoul, Gyeonggi, and Incheon region. This study used a 3D scanning instrument to obtain 16 facial anthropometric data points. Literature reviews, a comparison of breathing capacity between adults and children, and analysis of children's pulmonary physiological data were conducted in order to suggest new test standards for certifying children's masks against yellow dust and fine particulates. In addition, types of children's masks, choice of wearing a mask or not, and reasons for not wearing masks were surveyed. Results: Based on a clustering analysis of participants' facial dimensions, facial shapes were classified into three groups: small, medium, and large. The sizes of children's masks were subtracted by using 3D sketch techniques(Large: $121.25mm{\times}89.46mm$, Medium: $111.92mm{\times}78.55mm$, Small: $102.13mm{\times}72.87mm$). In certifying children's mask, flow rates of $60{\ell}/m$ for the filtering efficiency test and $20{\ell}/m$ for the breathing resistance test were recommended, since children's pulmonary physiological capacity is about 60-70% of adults' pulmonary capacity. Conclusions: The results of this study suggest that three mask sizes for children would be sufficient and practical for providing protection against yellow dust and fine particulates. Revising current test methods for certifying respiratory protective devices for children is important, since children's pulmonary physiological capacity substantially differs from that of adults. Therefore, it is recommended that new test standards for certifying children's masks be promulgated in the near future.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.629-636
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• 2003

The purpose of this study is localization of safety relief valves for Nuclear Service through technical development with overall design, fabrication, inspection, capacity certification test and functional qualification test of safety relief valves in accordance with ASME Section III and KEPIC Code. Safety relief valve is the important equipment used to protect the pressure vessel, the steam generator and the other pressure facility from overpressure by discharging the operating medium when the pressure of system is reaching the design pressure of the system. But we're depending on technology of the other country up to the present time. Because we don‘ have our own technologies, we have been spent the great time and money on installing and repairing safety relief valve at nuclear power plant. Therefore we have to achieve the development of safety relief valves for Nuclear Service with our own technologies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.236-247
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• 2020

This study was conducted with the aim of developing inspection tools to select and measure human resource figures and appropriate core competency of the educational goals pursued by S universities. Therefore, key competency factors were defined consistent with concept of talented figures and educational objectives of S universities, inspection tools were developed to measure core competences, and directions are presented for future education policies and curriculum compilation and securing data for rational operation. Based on key competency indicators, questions were developed in a self-reporting form that measures the consent level of the respondents by comprising seven areas of competence, 16 small areas (sub-capacity), and 46 questions. The main Test conducted an analysis of the questionnaires based on the survey results of 2,486 people to ensure the validity of the inspection by conducting a positive factor analysis and reliability analysis. The core competency diagnostic tool of S university is meaningful in this study which verifies the effectiveness of the curriculum and programs conducted at S university and as the first step for the rational operation of the core competency certification system to improve the competency appropriate for students.

• New & Renewable Energy
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• v.4 no.3
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• pp.45-50
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• 2008

GFRP based composite rotor blades were developed for 750 kW & 2 MW wind turbines. The blade sectional geometry was designed to have a general shell-spar and shear web structure. For verifying the structural safety under all relevant extreme loads specified in the GL guidelines, the structural analysis of the rotor blades was performed using commercial FEM codes. The static load carrying capacity, blade tip deflections and natural frequencies were evaluated to satisfy the strength and stability requirements. Full-scale proof tests of rotor blades were carried out with optical fiber sensors for real-time condition monitoring. Finally, the prototype of each rotor blade passed all proof tests for GL certification.