• Journal of the Society of Naval Architects of Korea
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• v.42 no.5 s.143
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• pp.435-447
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• 2005

The 24th ITTC Specialists Committee on Stability in Waves is conducting an international benchmark study where numerical methods for the calculation of ship motion in damaged condition are compared on the basis of specified tests in order to assess the present state of the art in this field. The study is finished and some results are presented in this paper providing an initial insight into the status of damage models and numerical methods and a collective assessment of their performance. The preliminary analysis has shown that current methods are satisfactory, capturing the fundamental physical performance of damaged ships in specified conditions.

• The Research Journal of the Costume Culture
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• v.29 no.6
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• pp.881-903
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• 2021

This study aimed to analyze adult men's body sizes and shapes and suggest size specifications to provide preliminary data to academia and industries. A total of 814 adult men aged 30-44 were selected from the 7th Size Korea data, and 55 direct upper body measurement and calculation items were analyzed using SPSS 25.0. In individual Individual differences, thickness, circumference, and width were high, and height and length were low. Height above the waist base line and shoulder dimension decreased in early 40s age group, while height below the waist base line declined as age increased. In addition, buttocks shape changes were found in early 40s age group. According to factor analysis, 'upper body and upper-extremity horizontal size', 'torso height and upper extremity length', 'shoulder dimension', 'upper body length' and 'shoulder angle' were derived. Using clustering analysis, four different body types were classified: i) big abdomen with flat chest, ii) slender with big, raised shoulders, iii) dwarfish with small, droopy shoulders, and iv) obese with large shoulders. 'Slender with big, raised shoulders' was a typical body shape among men aged 30-44. In older participants, the 'big abdomen with flat chest' ratio was low, while 'obese with large shoulders' was more common. This study proposed size specifications by body type considering the above characteristics.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2312-2322
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• 2021

In recent studies, the creep rate of Zircaloy-4, one of the basic property parameters of the nuclear fuel code, has been commonly used with the axial creep model proposed by Rosinger et al. However, in order to calculate the circumferential deformation of the fuel cladding, there is a limitation that a difference occurs depending on the anisotropic coefficients used in deriving the circumferential creep equation by using the axial creep equation. Therefore, in this study, the existing axial creep law and the derived circumferential creep results were analyzed through a circumferential creep test by the internal pressurization method in the isothermal conditions. The circumferential creep deformation was measured through the optical image analysis method, and the results of the experiment were investigated through constructed IDECA (In-situ DEformation Calculation Algorithm based on creep) code. First, preliminary tests were performed in the isotropic β-phase. Subsequently in the anisotropic α-phase, the correlations obtained from a series of circumferential creep tests were compared with the axial creep equation, and optimized anisotropic coefficients were proposed based on the performed circumferential creep results. Finally, the IDECA prediction results using optimized anisotropic coefficients based on creep tests were validated through tube burst tests in transient conditions.

• Journal of Korean Society of Rural Planning
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• v.29 no.4
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• pp.175-182
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• 2023

The purpose of this study, the trend of renewable energy, domestic and foreign renewable energy policies, and the flow of the legal system related to renewable energy location were identified, and a location analysis using public data was studied when solar energy was located. First, renewable energy is leading to energy conversion by reducing the proportion of existing fossil fuel-centered energy sources in the global trend and increasing the proportion of renewable energy, an eco-friendly energy source, and changing the institutional and market structure. Second, large-scale solar energy power plants are installed and operated in rural areas where there is no change in insolation and land prices are cheaper than in urban areas where there are many changes in insolation due to surrounding high-rise buildings and street trees. Third, if a preliminary location review is conducted using public data at this time, it will be easy to identify the optimal location for area and size calculation. Fourth, the solar energy location functional area was studied in area A, and the total area of the target area was 624.5km², with 392.7km² and 62.9% of the avoidance area where solar power cannot be located.

• Journal of The Korean Association For Science Education
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• v.29 no.3
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• pp.277-290
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• 2009

In the era of the outcome-based education, multiple-choice test has been widely employed owing to its efficiency that enables educators to evaluate a quantity of students with much objectiveness. However, the prevalent test has not been reconsidered enough to overcome its apparent shortcomings: examiners' effort for developing plausible and faultless distracters defending from every falsification, and students' random guessing on key choices. For alleviating such defects, tiered test as an experimental format of multiple-choice tests has been suggested in science education. Since there has not accumulated much study on the implementation of tiered tests, our research aim is set to construct a framework suggesting statistical indexes for rationally discerning tiered units that develop an effective tiered test. Graded both by our tiered-scoring and by the conventional partial-scoring, the preliminary tiered test in secondary physics attests the improvement in its discrimination and difficulty distribution. The findings reveal that the two indexes discern effective tiered items: discrimination increase (Ct-p) and difficulty decrease (Dp-t). Based on the index information, 4 heterogeneous tier types are recommended in the content of secondary physics: directional manipulation, repeated calculation, diverse explanation, and plural variables.

• Nuclear Engineering and Technology
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• v.56 no.6
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• pp.2274-2281
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• 2024

RESRAD-ONSITE v7.2 code is used to assess the radiation effects on a farmer resident located in a hypothetical contaminated site planned for the first nuclear power plant project in Vietnam, namely Ninh Thuan 1, after decommissioning. Derived concentration guideline levels are preliminarily calculated for 17 radionuclides that are assumed to remain on a contaminated surface soil with an initial concentration of 1 pCi/g in the protected area of NPP site. For a reliable estimation, the site-specific conditions regarding the geological, hydrological, climate, and occupancy data gathered from the Feasibility Study Report (FSR) and relevant literatures for the Ninh Thuan 1 NPP site is employed as input parameters. The calculation results indicate that the peak of total exposure dose is estimated to be ca. 0.191 mSv/yr at the time of decommissioning, and then decrease over time. Furthermore, the protected site is assessed to be released at ca. 6.71 years after decommissioning under the regulation on radiation protection in Vietnam. Through this study, a radiation exposure model for residents living near the Ninh Thuan 1 NPP is preliminarily established by using the RESRAD-ONSITE code, which are expected to be useful for future implementation of the Ninh Thuan 1 NPP project in Vietnam.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.20 no.1
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• pp.8-15
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• 2024

This study aims to investigate the possibility of expanding the support program for green remodeling of fire stations and analyze the standard design guidelines. Green remodeling is essential for reducing greenhouse gas emissions and promoting green buildings, but currently, it is only conducted for buildings with limited purposes. In this study, we conduct green remodeling for fire stations with severe aging to demonstrate energy performance improvement and investigate the potential for expanding the support program to other types of aging buildings. The research methodology includes analysis of previous studies, preliminary investigation and alternative setting, energy analysis, calculation of construction costs, evaluation of the possibility of introducing support programs, and examine of the fire station standard design guidelines. The research results confirm that green remodeling can reduce energy consumption in fire stations and present the possibility of including fire stations as targets in the support program for green remodeling of public buildings.

• Progress in Medical Physics
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• v.22 no.3
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• pp.124-130
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• 2011

In this study the dosimetric evaluation for a biological sample irradiated by gamma rays from Cs-137 irradiator (Gamma Irradiator, Chiyoda Technol Co., Japan) was performed for radiobiological experiment. A spherical water with a diameter of 3 cm was assumed as a biological sample. The absorbed dose were determined by the air kerma based dosimetric calculation system. The theoretical and Monte Carlo calculations (MCNPX) were performed and compared to evaluate measured air kerma and determined absorbed dose respectively. As a result of comparison with theoretical calculation, the measured air kerma was in good agreement within 3.1% at the distance of 100 and 200 cm from the source. In comparison with Monte Carlo results the determined absorbed dose along the central axis was in good agreement within 1.9% and 3.7% at 100 cm and 200 cm respectively. Although the preliminary results were obtained in this study these results were used as a basis of dosimetric evaluation for radiobiological experiment. Extended study will be performed to evaluate the dose in various conditions of biological samples.

• Journal of the Society of Disaster Information
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• v.19 no.1
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• pp.18-30
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• 2023

Purpose: This study is to contribute to the development of monitoring technology through the increase of confidence in construction monitoring by deriving the analysis of construction monitoring cost and improvement measures of railway tunnel construction in Seoul. Method: It presents the status on design and contract of construction monitoring cost, status on application construction monitoring cost and its analysis, analysis on safety management cost and quality management cost, expansion of application of the price calculation standard for monitoring management services to improve this, and monitoring for direct order of ordering organization. Results: If the monitoring management service that was meanwhile ordered as included in the construction work is performed by the directly selected company of ordering organization through the preliminary screening for bidding qualification, then the improvement of monitoring quality and the accurate monitoring data can be secured. Conclusion: For the price calculation standard for monitoring management service, the application of actual cost addition method under the Engineering Promotion Act and the calculation standard of monitoring management cost for standard estimation for ground survey should be extended through the direct order of ordering organization, not the method to be included in the net construction cost where it is performed by a subcontractor via contractor.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.95-105
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• 2014

The CUPID code has been developed for a transient, three-dimensional, two-phase flow analysis at a component scale. It has been validated against a wide range of two-phase flow experiments. Especially, to assess its applicability to single- and two-phase flow analyses in the Calandria vessel of a CANDU nuclear reactor, it was validated using the experimental data of the 1/4-scaled facility of a Calandria vessel at the STERN laboratory. In this study, a preliminary thermal-hydraulic analysis of the CANDU reactor moderator tank using the CUPID code is carried out, which is based on the results of the previous studies. The complicated internal structure of the Calandria vessel and the inlet nozzle was modeled in a simplified manner by using a porous media approach. One of the most important factors in the analysis was found to be the modeling of the tank inlet nozzle. A calculation with a simple inlet nozzle modeling resulted in thermal stratification by buoyance, leading to a boiling from the top of the Calandria tank. This is not realistic at all and may occur due to the lack of inlet flow momentum. To improve this, a new nozzle modeling was used, which can preserve both mass flow and momentum flow at the inlet nozzle. This resulted in a realistic temperature distribution in the tank. In conclusion, it was shown that the CUPID code is applicable to thermal-hydraulic analysis of the CANDU reactor moderator tank using the cost-effective porous media approach and that the inlet nozzle modeling is very important for the flow analysis in the tank.