• Journal of the Korea Safety Management & Science
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• v.17 no.4
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• pp.397-401
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• 2015

In this study, analysed the characteristics of power drop and surface damage in solar cell through high temperature and humidity test in the 3 case of EVA(ethylene vinyl acetate) and 2 case ribbon thickness. The solar cells were tested during the 500hr in $85^{\circ}C$ temperature and 85% relative humidity conditions, that excerpted standard of PV Module(KS C IEC-61215). Through the EL(Electroluminescence) shots, specimen's surface have partialy damaged. Before and after high humidity and high temperature test, ribbon thickness $200{\mu}m$ EVA1 case power drop rate was 8.463%, EVA2 case was 6.667%, EVA3 case was 6.373%. In the ribbon thickness $250{\mu}m$ EVA1 case power drop rate was 6.521%, EVA2 case was 8.517%, EVA3 case was 6.019%. EVA3 case was the lowest power and FF(fill factor) drop rate at the 2 case of ribbon thickness, because EVA3 is laerger than EVA1 and EVA2 in thickness, elongation and tensile strength.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.571-578
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• 1997

In the repair and repair works, epoxy resins are widely used as repair materials. The successful concrete repairs and retrofit works depends on the quality of the repair and retrofit materials. Although many materials for the repairs and retrofit have been developed in many contries, information on the repair methods are somewhat limited. Futhermore, the repairs and retrofit methods are also largely dependent on those froms in other developed contries, it is necessary to initiate rather fundamental repair-related research. The purpose of this study is to investigate th physical and mechanical properties of epoxy resin which is commonly used in repairing concrte crack in RC structures. The basic physical properties such as specific gravity, gel point and shrinkage ratio as well as the mechanical properties such ad the tensile and compressive strength, elastic modulus were acquired by the standard test method (KS code). For the test results, the great deviations of physical and mechanical properties among the test materials were discovered and is, therefore, recommended that careful attentions should be give in selecting the epoxy resin by considering the characteristics of the repair materials and repair works.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.3
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• pp.414-422
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• 2011

In this paper, we analyze the standards of the bolts for maintaining the products. The maintainer don't know the detail information of bolts by seeing the shape of bolts when they repair the products. So they waste much time and cost. To solve the these problem, we propose the new systematical discrimination of bolts. To propose the discrimination code, we divide the shapes of the bolts into four classes(head, internal drive, shank and end). User can fine preferentially similar standards by just the shapes of bolts under the this discrimination code. And, User can find the standards of bolts that they want by using the additional information such as measurements. We will reduce the cost and time for the maintaining the products by using the proposed discrimination code.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.979-988
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• 2017

The feasibility of cooling in a pressurized heavy water reactor after a large break loss-of-coolant accident has been analyzed using Multidimensional Analysis of Reactor Safety-KINS Standard code during the recirculation phase. Through evaluation of sensitivity of the fuel channel temperature to various effective recirculation flow areas, it is determined that proper cooling of the fuel channels in the broken loop is feasible if the effective flow area remains above approximately 70% of the nominal flow area. When the flow area is reduced by more than approximately 25% of the nominal value, however, incipience of boiling is expected, after which the thermal integrity of the fuel channel can be threatened. In addition, if a dramatic reduction of the recirculation flow occurs, excursions and frequent fluctuations of temperature in the fuel channels are likely to be unavoidable, and thus damage to the fuel channels would be anticipated. To resolve this, emergency coolant supply through the newly installed external injection path can be used as one alternative means of cooling, enabling fuel channel integrity to be maintained and permanently preventing severe accident conditions. Thus, the external injection flow required to guarantee fuel channel coolability has been estimated.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.10
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• pp.1-8
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• 2021

Cylinder liners used in diesel engines of combat equipment are prone to cavitation due to wet cooling. The damage caused by erosion and corrosion due to cavitation has a fatal effect on the performance and lifespan of a diesel engine. Therefore, a study was conducted to improve the durability of cylinder liners. Two surface treatment techniques were proposed: nitriding and chrome plating. It was observed that the amount of erosion on the surface of nitride-treated cylinder liners was high because the surface-treated part eroded due to its weak impact resistance against the bubble explosion generated by cavitation. In contrast, the chrome-plated cylinder liner had a lower amount of erosion among the specimens subjected to the accelerated test. These results verified that the resistance of chrome-plated liners against cavitation is high. Therefore, it can withstand the impact of bubble explosion. If the chrome plating thickness is set with reference to the KS standard, an exceptional durability of abrasion, wear resistance, and corrosion resistance can be obtained. If the thickness is set between 120~250㎛, it is expected that the durability of the cylinder liner can be improved. Although a recovery method for corroded cylinder liners is suggested, the proposed method has an inherent risk of crack generation. Therefore, further research is required to solve this problem.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.10
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• pp.199-206
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• 2019

This study aims to recycle redmud which is a byproduct in the alumina industry. Redmud ceramics were prepared according to the type of raw materials by blending redmud with the raw materials used in the conventional clay bricks. In this paper, the compressive strength, water absorption ratio, and shrinkage of redmud ceramics prepared by mixing clay bricks were evaluated. Compressive strength and absorption ratio of redmud ceramics were compared with the clay brick criteria of KS L 4201. At the firing temperature of $1200^{\circ}C$, the specimens containing redmud only and the redmud with sandy loam and black clay were found to satisfy the 1st class of clay brick. The quality standard of compressive strength and absorption ratio was obtained by firing redmud with black clay and sandy loam at $1200^{\circ}C$. Also, when the redmud was mixed with black clay and feldspar, the 2nd class was satisfied when the sample was fired at $1100^{\circ}C$.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.3
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• pp.145-158
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• 2022

To grasp the size system of children's clothing online shopping malls, basic size charts for clothing products from 14 shopping malls were collected, compared, and analyzed. Looking at the age range of the basic size chart for each company, the minimum age is 1 year old, the maximum age is 14-15 years old, and all companies included ages up to 7 years. In addition, as for the number of size designations, children's clothing companies used seven to eight designations, and there were six types of size designation methods. Next, looking at the height range for each size, even with the same size designation method, the height range differed depending on the company. Also, the KS size standard does not consider body weight, but many companies use weight as a reference body size. Compared with the child body size data of the 6th Korean Body Size Data, the height and weight range for each size provided by the company showed differences between companies. The results of this study can be used in the future as basic data when revising and supplementing the clothing sizes in children's clothing companies.

• Journal of the Korean Society of Safety
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• v.35 no.2
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• pp.8-16
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• 2020

In Article 311 of the Regulation on Occupational Safety and Health Standards requires the use of Korean Industrial Standards Act in accordance with the Industrial Standardization Act. However, the classification, inspection, maintenance, design, selection, and installation of explosion hazard locations for explosion and explosion prevention and internalization of 'safety' in the performance maintenance phase of electrical machinery and equipment There is no technical and institutional management plan for remodeling and alteration. Analysis of actual conditions and problems related to the installation, use, and maintenance of explosion-proof equipment, comparative analysis of domestic and international technical standards and systems, technical, institutional and administrative systems and systems related to installation, use, and maintenance of explosion-proof equipment, technical personnel and qualifications, etc. It is to propose legislation, system improvement, and technical standard establishment related to the maintenance of explosion-proof facility performance through improvement of the necessity and feasibility study for establishment of the legal status of the management site and management plan. As technical measures, KS standard revision (draft), KOSHA guide (draft) and explosion-proof facility performance maintenance manual were presented. In addition, the institutional management plan proposed the revised rule on occupational safety and health standards, the revised rule on the restriction of employment of hazardous work, and the manpower training program related to the maintenance of explosion-proof facilities and the qualification plan. Enhance safety at the installation, use, and maintenance stage of explosion-proof structured electrical machinery. It is expected to be used to classify explosion hazards, select related equipment, and to update and standardize standards related to installation, use and maintenance.

• Journal of the Korean Institute of Educational Facilities
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• v.23 no.2
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• pp.11-18
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• 2016

University dorm basically provides basic housing functions to students, however, it is very important in a sense that it provides students with various functions such as information exchange, cultural experience and learning environments as well. Additionally, continuous effort to improve users' satisfaction and living environments are needed due to the fact that physical environments of dorm facilities have higher impact on students. However, Many students are not satisfied with the physical environment of university dorms and also there is lack of systematic information whereas various functions are required by students. Therefore, the main objective of this research is to suggest the direction of FM services in order for improving students' satisfaction on the university dorm facilities in Korea. Precedent studies regarding the satisfaction or performance evaluation of dorm facilities have been extensively analyzed to extract the dissatisfaction factors that scored below the middle 50%. Secondly, for satisfaction improvement, Korean Standard for Facility Management(KS_FM) have been matched with those extracted dissatisfaction factors to suggest the direction of FM services by rules and regulations review and best practice studies. This research will be useful for university dorm facility managers in planning strategic FM and providing effective FM services to students.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.2
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• pp.231-243
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• 2012

This study examines the characteristics of fat body type males aged 35 to 55 with a BMI rate higher than 25 categorized as mid-degree obesity and high-degree obesity according to the $6^{th}$ Size Korea; in addition, the study provides a sizing system for obese males. The physical characteristics of the obese male appeared to be with a shorter lower body compared to an upper body for a higher degree of obesity. Obesity appeared evenly from chest to thigh circumference compared to a normal group. Especially, their waist measurement, depth, and width were significantly larger as well as the crotch length (natural indentation) and a larger waist measurement. As for the cloth sizing system, this study suggests the sizes with higher distribution among the designated size intervals of casual tops, men's suit tops and bottoms based on standard stature, chest size and waist circumference (Omphalion) by KS.