• 한국환경과학회지
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• 제27권2호
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• pp.75-81
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• 2018

At present research on mining backfill materials is being carried out to prevent ground subsidence and breaking by underground cavern of exhausted mines. However, backfill materials can cause secondary environmental issues such as ground pollution. To solve these issues, liner and cover materials are constructed before backfill materials constructed, to inhibit toxic substances form moving to the surroundings. Liner and cover materials, however, should have an accelerating performance after construction and when the accelerating performance is degraded, the work efficiency can be lowered, and the construction cost can be increased, by many rebound content. Therefore, this study develops mining liner and cover materials, and evaluates their accelerating performance and physical properties of liner and cover materials by types and content of accelerating agent. In case of aluminate accelerating agent, it is mixed with more than 5% of liner and cover materials(binder/ratio); thus an accelerating performance satisfying Korean Industrial Standards(KS) occurs, and in case of alkali-free accelerating agent, when it is mixed with more than 7%(binder/ratio), accelerating performance satisfying KS occurs. The more the accelerating agent capacity increases, the more compressive strength decreases. In addition, it is confirmed that compressive strength of aluminate accelerating agent is more degraded than compressive strength of the alkali-free accelerating agent. It is also confirmed that drying shrinkage stability of the alkali-free accelerating agent is better than the drying shrinkage stability of the aluminate accelerating agent.

• Nuclear Engineering and Technology
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• 제37권3호
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• pp.273-278
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• 2005

Key concepts in South Korean nuclear safety regulation are safety and risk. Nuclear regulation in South Korea has required reactor designs and safeguards that reduce the risk of a major accident to less than one in a million reactor-years-a risk supposedly low enough to be acceptable. To date, in South Korean nuclear safety regulation has involved the establishment of many technical standards to enable administration enforcement. In scientific lawsuits in which the legal issue is the validity of specialized technical standards that are used for judge whether a particular nuclear power plant is to be licensed, the concept of uncertainty law is often raised with regard to what extent the examination and judgment by the judicial power affects a discretion made by the administrative office. In other words, the safety standards for nuclear power plants has been adapted as a form of the scientific technical standards widely under the idea of uncertainty law. Thus, the improvement of nuclear safety regulation in South Korea seems to depend on the rational lawmaking and a reasonable, judicial examination of the scientific standards on nuclear safety.

• Corrosion Science and Technology
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• 제20권1호
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• pp.7-14
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• 2021

PosMAC^® is a brand of Zn-Mg-Al hot-dip coated steel sheet developed by POSCO. PosMAC^® can form dense surface oxides in corrosive environments, providing advanced corrosion resistance compared to traditional Zn coatings such as GI and GA. PosMAC^® 3.0 is available for construction and solar energy systems in severe outdoor environments. PosMAC^®1.5 has better surface quality. It is suitable for automotive and home appliances. Compared to GI and GA, PosMAC^® shows significantly less weight reduction due to corrosion, even with a lower coating thickness. Thin coating of PosMAC^® provides advanced quality and productivity in arc welding applications due to its less generation of Zn fume and spatters. In repeated friction tests, PosMAC^® showed lower surface friction coefficient than conventional coatings such as GA, GI, and lubricant film coated GA. Industrial demand for PosMAC^® steel is expected to increase in the near future due to benefits of anti-corrosion and robust application performance of PosMAC^® steel.

• 한국IT서비스학회지
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• 제21권5호
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• pp.107-127
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• 2022

Personal broadcasting utilizing Vtuber, a virtual creator made of 2D or 3D avatars, has recently appeared and is growing in popularity. Vtuber is a virtual person who broadcasts on the Internet using 2D or 3D avatars with real-time motion capture and computer graphics technologies. While the personal broadcasting industry utilizing Vtuber is proliferating, related studies have mainly concentrated on technical issues. Therefore, in this study, the antecedent factors that form the technical characteristics and virtual creator characteristics of Vtuber personal broadcasting are derived using the Stimulus-Organism-Response (S-O-R) model. Then the effect of these factors on viewer pleasure and satisfaction, which lead to increased paid sponsorship is to be examined. Furthermore, we investigate how this influencing mechanism fluctuates based on the avatar type (2D vs. 3D). This study contributes to empirical examinations of viewers' paid sponsorship intention in Vtuber personal broadcasting through the S-O-R model. It also offers insights that technological or virtual creator characteristics could improve viewers' pleasure, satisfaction, and even paid sponsorship.

• Nuclear Engineering and Technology
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• 제55권9호
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• pp.3464-3471
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• 2023

The Uranium/Molybdenum metallic fuel has been proposed as promising advanced fuel concept especially in the dispersed fuel geometry. The fuel is manufactured in the form of small fuel droplets (particles) placed in a fuel pin covered by a matrix. In addition to fuel particles, the pin contains voids necessary to compensate material swelling and release of fission gases from the fuel particles. When investigating this advanced fuel design, two important questions were raised. Can the dispersed fuel performance be analyzed using homogenization without significant inaccuracy and what size of fuel drops should be used for the fuel design to achieve optimal utilization? To answer, 2D burnup calculations of fuel assemblies with different fuel particle sizes were performed. The analysis was supported by an additional 3D fuel pin calculation with the dispersed fuel particle size variations. The results show a significant difference in the multiplication factor between the homogenized calculation and the detailed calculation with precise fuel particle geometry. The recommended fuel particle size depends on the final burnup to be achieved. As shown in the results, for lower burnup levels, larger fuel drops offer better multiplication factor. However, when higher burnup levels are required, then smaller fuel drops perform better.

• Structural Engineering and Mechanics
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• 제45권3호
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• pp.411-422
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• 2013

A well-designed mesh shape of the cable net is of essential significance to achieve high performance of cable-network antenna reflectors. This paper is concerned with the mesh design problem for such antenna reflector structure. Two new methods for creating the topological forms of the cable net are first presented. Among those, the cyclosymmetry method is useful to generate different polygon-faceted meshes, while the topological mapping method is suitable for acquiring triangle-faceted meshes with different mesh grid densities. Then, the desired spatial paraboloidal mesh geometrical configuration in the state of static equilibrium is formed by applying a simple mesh generation approach based on the force density method. The main contribution of this study is that a general technical guide for how to create the connectivities between the nodes and members in the cable net is provided from the topological point of view. With the new idea presented in this paper, multitudes of mesh configurations with different net patterns can be sought by a certain rule rather than by empiricism, which consequently gives a valuable technical reference for the mesh design of this type of cable-network structures in the engineering.

• 한국패션뷰티학회지
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• 제5권1호
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• pp.71-77
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• 2007

This study attempted to comparative analysis about the physical and morphological damage degrees of hair according to the bleaching methods by $H_2O_2$ concentration. As a result of the changes in the physical characteristics of the hair according to the deceleration operation methods by 3-6-9% and 9% $H_2O_2$ concentration, the intensity of tension considerably decreased but the elongation was increased. And the more the damage of hair, the larger the degree of change. Regarding the method of deceleration operation, the 3-6-9% deceleration operation method was more damaging than the 9% single deceleration operation method. In the change of the characteristics of the form of the hair, the control group of the 5-level deceleration hair generally showed a smooth external appearance and regular and closely overlapped epidermis and undamaged cuticle were observed. But in the 3-6-9% deceleration operation method and 9% single deceleration operation method, damages such as the irregular form of the edge of the epidermis and the unclear boundary between the epidermis occurred.

• 한국콘텐츠학회논문지
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• 제20권9호
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• pp.158-168
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• 2020

본 논문은 한국 아이돌 팬 창작물의 텍스트 생성 과정과 코드화를 분석했다. 아이돌 팬 창작물이란, 창작 주체인 팬이 아이돌 콘텐츠를 원전으로 삼아 텍스트를 창작한 콘텐츠이다. 본 논문의 주요 연구 대상으로는 스토리텔링을 기반으로 하는 남성 아이돌 그룹인 '방탄소년단'과 '엑소'의 팬 창작물을 채택했다. 이론적으로는 빌렘 플루서의 '기구-작동자'와 '기술적 형상'의 개념을 적용해 분석했다. 분석 결과, 아이돌 콘텐츠는 팬 해석의 분화와 통합을 통해서 팬 창작물의 데이터베이스를 구축하고 통합적 스토리 월드를 생성한다. 이때 팬들은 코드를 생성하고 작동시키는 기구-작동자이다. 팬들은 아이돌 콘텐츠의 특정 부분을 탈맥락화하며 원전 텍스트를 강화하고 구조적 완결성과 자율성을 추구한다. 동시에 아이돌 콘텐츠의 중첩되는 부분을 재맥락화하고 원전 텍스트의 영역을 확장한다. 결과적으로 한국 아이돌 팬 창작물은 사용자이자 창작 주체인 팬의 의식과 가치를 담아낸다는 점에서 코드화된 기술적 형상으로 작동한다.

• 복식
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• 제57권2호
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• pp.155-171
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• 2007

Exaggerated expressions of contemporary fashion have exceeded historical precedents in volume. The purpose of this study is to understand the aesthetic characteristics of expanded form In contemporary fashion. To take dresses beyond their flat shapes into three-dimensional forms, it was investigated into volume of dresses by using the void and the mass. The void Is rarefied space and the mass is densified space. The void of dresses could be constructed from the boning such as panier and stiff textiles as organza lining. The mass could be constructed from padding. Fold, pleats, twist, and the layering of fabrics show features of both the void and the mass. Contemporary fashion designers relied on the void rather that the mass to make the enormous volume because of the weight of the mass. X-silhouette and the expansion of skirt and sleeve were dominant as the result of accentuating the body with a waistline. However, many of expanded dresses were so voluminous that they obscured the body's outlines. Some forms were strange and shocking. Many designers explored the void and there were a multitude of methods to construct the void: compartments of air, architectural techniques, technical textiles, fold such at origami. The aesthetic consciousness of expanded dresses could be classified into 7 categories, the giant, the dynamic, the deconstructive, the historical, the comedic, the rhythmical, and the technical character.

• 대한조선학회논문집
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• 제47권3호
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• pp.469-475
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• 2010

The operation scenarios, types of ice, draft and propulsion system are important design point on the beginning stage of the ice breaking vessel. The concept of hull form in ice breaking vessel has to compromise the performance according to the operation route especially if ship is operating in ice and ice free water. The several hull forms were proposed to optimize the capability of the vessel in this paper. The effect of hull form according to type of ice is also discussing and explaining the ice resistance in each ice type as like pack ice, brash ice, level ice, rubble ice and ice ridge. The draft effect was examined and propulsion system for example FPP(Fixed pitch propeller), CPP(Controllable pitch propeller) and POD system was compared focusing on the propulsion efficiency.