• 콘크리트학회논문집
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• 제11권3호
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• pp.101-111
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• 1999

Compared with the BF slag, the EAF slag has expansion due to the reaction with water and free CaO. Therefore it is specified in Concrete Specification that the FAP slag aggregated must not be used in concrete. Because of this reason it is unusual to use the EAF slag aggregate in concrete. The EAF slag aggregate treated with accelerated and water aging was comparatively satisfied with fundamental properties, which are specific gravity, unit weight, abrasion and immersion expansion ratio, as concrete aggregate. Therefore when we measured the compressive strength till 28 days, we found that the mortar and concrete replacing the natural aggregate with the EAF slag aggregate by 4 steps had better results than the concrete using the natural aggregate in a view of the compressive strength. But at 91 days, concrete using the EAF slag aggregate had no difference with it using the natural aggregate.

• 한국농공학회지
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• 제35권4호
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• pp.38-46
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• 1993

This study is to analyze effect of exposure environment and mode of ASR on the engineering properties of synthetic lightweight aggregate concrete, such as dynamic modulus of elasticity and ultrasonic pulse velocity. The results of this study are summarized as foflows ; 1. The expansion rate of each exposure environment in 380$^{\circ}$C and NaCI 4% solution was shown higher than in 20$^{\circ}$C and normal water. The expansion rate of each exposure mode was largely shown in order of fjill immersion, wetting/drying, half immersion. 2. The dynamic modulus of elasticty and ultrasonic pulse velocity of each exposure environment in 38$^{\circ}$C and NaCl 4% solution was shown less than in 20$^{\circ}$C and normal water. The dynamic modulus of elasticity and ultrasonic pulse velocity of each exposure mode was shown smaller in order of full immersion, wetting/drying, half imersion.3. The relation between dynamic modulus of elasticity and ultrasonic pulse velocity was highly significant. The dynamic modulus of elasticity was increased with increase of ultrasonic pulse velocity. The decreasing rate of the dynamic modulus of elasticity was shown 2.1~3.4 times higher than the ultrasonic pulse velocity at each age, exposure environment and mode, respectively. 4. The expansion of each exposure environment and mode was increased with increase of curing age. The dynamic modulus of elasticity and ultrasonic pulse velocity of those concrete was increased with increase of curing age. At the curing age 28 days, the highest properties was showed at each type concrete, it was gradually decreased with increase of curing age. Specially, at the curing age 98 days of full immersion, the rate of expansion of type D was shown 3.95 times higher than the type A. But the dynamic modulus of elasticity and ultrasonic pulse velocity was decreased 17% and 8.3%.

• 한국멀티미디어학회논문지
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• 제25권6호
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• pp.844-851
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• 2022

This study intends to propose an evaluation tool for analyzing the sense of immersion of realistic VR game contents in the metabus game industry, which is rapidly increasing recently. This paper presents an analysis tool to measure the degree of immersion after selecting three types VR games for research, and analyzing the immersion way method of the game. The research method analyzes how the user and the sense of immersion formed in the storytelling in the game can have an effect. Based on the results, we present an sense of immersion analysis and measurement method for evaluating the usability of VR game contents, which is a key element in the metaverse era. Furthermore, it expands the immersion element that appears in storytelling to the game industry and seeks a new direction of development through connection with the VR game industry.

• International Journal of Internet, Broadcasting and Communication
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• 제15권1호
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• pp.8-12
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• 2023

With the recent expansion of online lectures, studies on their effectiveness and their influencing factors have increased. This study examines the factors affecting the satisfaction of online classes, considering the utilization and importance of online lectures, which have greatly increased in recent years. Based on the review of previous studies, this study identified learning presence, self-efficacy, and learning immersion as factors affecting the satisfaction of online classes, and suggested hypotheses that explain the relationship between these factors, and empirically reviewed the hypotheses. As a result of the study, it was found that learning presence and self-efficacy had a positive effect on learning immersion, and learning immersion had a positive effect on learning satisfaction. Based on the research results, some practical implications for improving the satisfaction of online classes were suggested.

• 한국신뢰성학회지:신뢰성응용연구
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• 제9권4호
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• pp.275-290
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• 2009

This paper considers accelerated thermal degradation tests which are performed for rubber seal materials used for undersea tunnels constructed by immersion method. Three types of rubber seals are tested; rubber expansion seal, omega seal, and shock absorber hose. Main ingredient of rubber expansion seal is EPDM(Ethylene Propylene Diene Monomer) and that of both omega seal and shock absorber hose is SBR(Styrene Butadiene Rubber). The accelerated stress is temperature and an Arrhenius model is introduced to describe the relationship between the lifetime and the stress. From the accelerated degradation tests, dominant failure mode of the rubber seals is found to be the loss of elongation. The lifetime distribution and the service life of the rubber seals at use condition are estimated from the test results. The acceleration factor for three types of rubber seals are also investigated.

• 한국의류학회지
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• 제47권3호
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• pp.492-510
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• 2023

The metaverse, an expansion of the real world, refers to a three-dimensional virtual world where daily life and economic activities can be conducted through avatars. This study examines the effect of avatar identification on metaverse immersion, vicarious pleasure, and fashion brand item sharing intention by subdividing avatar identification into similarity identification, wishful identification, and embodied presence. In addition, it investigates the difference in the influence relationship between avatar identification, immersion, and vicarious pleasure according to the degree of fashion involvement. The total of 319 participants were analyzed using SPSS 26.0 and AMOS 24.0. The results showed that similarity identification, wishful identification, and embodied presence had significant impacts on immersion and vicarious pleasure, influencing sharing intention. There was also a difference in the effect of avatar identification on consumer responses depending on fashion involvement. This study provides theoretical implications for experiential marketing and presents practical suggestions for developing metaverse marketing strategies.

• 한국건설순환자원학회논문집
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• 제2권1호
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• pp.128-135
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• 2006

제강슬래그 중 콘크리트용 골재로 활용 가능성이 있는 전기로슬래그 골재에 대하여 촉진에이징 종류별 전기로슬래그 골재의 팽창성 감소 정도를 파악하고, 콘크리트용 최적 에이징 처리 방법 및 처리 기간을 제시하고자 하였다. 또한, 에이징 처리 후에도 전기로슬래그 골재 내부에 잔류되어 있는 팽창성이 콘크리트에 미치는 영향 및 콘크리트의 품질을 비교, 고찰하였다. 전기로슬래그 골재의 수침팽창 측면에서 온수중 에이징 방법이 증기중 에이징 방법보다 다소 우수한 결과를 나타내었다. 전기로슬래그 골재의 잔류팽창과 콘크리트의 압축강도를 비교한 결과 콘크리트용으로 전기로슬래그 골재를 사용하기 위해서는 에이징 처리에 의해 잔류팽창을 0.06% 이하로 충분히 낮춘 후 사용해야 한다. 또한 현재 도로용으로 한정되어 사용되고 있는 전기로슬래그를 콘크리트용 골재로 사용하기 위해서는 골재의 품질개선 뿐만 아니라 감수제 및 AE제 등 적절한 혼화재료의 사용이 필요하겠다.

• 한국결정성장학회지
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• 제31권6호
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• pp.247-257
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• 2021

본 연구는 오토클레이브 양생시편이 예상과 달리 초기강도는 잘 발현되지 않는 반면, 수중에 장기 침지할 경우 압축강도가 향상되는 현상을 규명하기 위해 시작되었다. 증류수 및 알칼리 용액에 침지하였고, 세 가지 양생방법이 시도되었다. 알칼리용액에 침지할 경우 증류수 침지 시편이 추가적인 지오폴리머 반응에 의해 보다 더 높은 압축강도를 가질 것으로 예상하였으나, 실제로 추가적인 지오폴리머 반응에 의해 생성된 결정립들과 알칼리골재 반응에 의한 시편의 팽창 때문에 21일 침지 후 침지용액에 의한 압축강도의 변화는 크게 나타나지 않은 것으로 사료되었다. 지오폴리머의 수중 및 알칼리용액 내 장기공용성을 확보하기 위해서는 오토클레이브를 이용하여 양생 후 21일 이상 수중 침지를 시키면서 숙성(aging) 시키는 것이 바람직 한 것으로 결론지을 수 있었다.

• 한국건축시공학회지
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• 제24권3호
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• pp.297-308
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• 2024

본 연구에서는 화재로 손상된 콘크리트의 손상 깊이 판정방법을 제안하고자 하였다. 고온에 노출된 콘크리트의 경우 내부 조직이 팽창하여 건전한 부위보다 손상부위의 공극이 다량 발생하고 미세균열이 발생됨에 따라 흡수율이 더 높아져 수중 침치후 건조를 하는과정에서 건전부위보다 손상부위의 늦은 건조속도와 이에 따른 명도차이에 의한 색상차이를 이용하여 손상 깊이를 측정하는 것이다. 수중 침지방법의 경우 배합별로 각각 38.7 및 37.5mm로 나타났는데, 기존 페놀프탈레인에 의한 중성화 측정 방법보다 손상깊이를 깊게 추정하는 것을 알 수 있었다. 이는 Portlandite(Ca(OH)₂)의 존재여부에 따라 발색이 되는 페놀프탈레인법에 비해 조직이완에 따른 흡수율 원리를 이용한 손상 깊이를 측정하는 방법이 더 민감도가 높아 얻어진 결과로 사료된다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2021년도 춘계학술대회
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• pp.320-322
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• 2021

무선 인터넷 기술이 발달하고 게임 시장이 확대됨에 따라 모바일 플랫폼을 포함한 다양한 플랫폼에 탑재되는 다양한 형태의 게임이 개발되고 있다. 이러한 환경에서 게임 사용자 관점의 몰입감을 보장하는 것이 게임의 경쟁력을 확보할 수 있게 되므로 HCI(Human Computer Interaction) 이론에서 제시하는 각 영역을 충족시켜 몰입감을 늘리는 것이 필요하다. 이를 위하여 본 고에서는 게임 사용자의 게임 진행의 자유도를 확보하고 몰입감을 확보하기 위한 방안으로써 인체의 동작을 인식하는 방식의 인터페이스를 적용하여 활강 게임을 구현하고 키오스크에 탑재하여 실험하였다.