• Title/Summary/Keyword: 공간전이단계

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Technology of Medical Image Security using Cellular Automata Transform (CAT를 이용한 의료영상보안 기술)

  • Nam, Tae-Hee
    • Proceedings of the Korea Multimedia Society Conference
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    • 2012.05a
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    • pp.332-335
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    • 2012
  • 본 논문에서는 CAT(Cellular Automata Transform) 성질을 이용하여 의료 영상의 단계적 변환을 제안한다. 적용 방법은 먼저, CAT 초기 값과 다양한 규칙에 따라 단계적으로 Gateway Values와 rule matrix에 대한 전이행렬 T를 이용하여 CAT 기저함수를 생성한다. 그런 다음, 생성된 CAT 기저함수를 의료 영상에 곱하여 영상을 다양한 방법으로 변환한다. 마지막으로, 키 공간 분석을 통하여 제안한 방법이 높은 영상 변환 및 보안의 성질을 가졌음을 검증한다.

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Enhancement in Performance of $Pt/CeO_2$ Catalysts for Single Stage Water-Gas Shift (WGS) Reaction via Controlling the Preparation Conditions (제조 조건 조절을 통한 수성가스전이 반응에서 $Pt/CeO_2$ 촉매 성능 강화)

  • Eum, Ic-Hwan;Jeong, Dae-Woon;Kim, Ki-Sun;Roh, Hyun-Seog;Koo, Kee Young;Yoon, Wang Lai
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.229.2-229.2
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    • 2010
  • 한 단계 수성가스전이반응(Single stage water gas shift reaction)을 위해 높은 산소저장능(OSC: Oxygen Storage Capacity)을 가진 $CeO_2$를 담체로 사용하여 $Pt/CeO_2$ 촉매를 설계하였다. 촉매의 제조 조건은 촉매 활성과 매우 밀접한 관계가 있다. 따라서 $Pt/CeO_2$ 촉매에 제조변수를 다양하게 변화하여 성능을 평가하였다. 촉매 반응 실험은 공간속도(GHSV: Gas Hourly Space Velocity) $45,515h^{-1}$에서 수행하였다. 본 연구에서는 $Pt/CeO_2$ 촉매를 최적화하기 위해 촉매 제조 조건 중 소성온도, 배치 당 제조질량, 전구체 그리고 pH 와 같은 다양한 제조 조건으로 촉매의 성능을 평가하였다.

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A Study on the Analysis of Gameness Transition in Media Contents :Focused on Chris Crawford's model (미디어 콘텐츠에 나타난 게임성 전이 분석 연구 :크리스 크로포드의 모델을 중심으로)

  • Kim, Eun-Jung
    • Journal of Korea Game Society
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    • v.19 no.6
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    • pp.37-48
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    • 2019
  • This paper aims to clarify the game performance and its principle and operation method at the depth of successful content through gameness transition, which is one of the transmedia phenomena of games. This paper investigated the current state of gameness transition and analyzed the game structure and working principle by using Chris Crawford's creative expression taxonomy model. As a result, the types of gameness transition could be extracted into space exploration type, stage type, reasoning competition type, and mutual competition type.

Pt/$Ce_{(1-x)}Zr_{(x)}O_2$ catalyst optimization for water gas shift reaction (WGS 반응용 Pt/$Ce_{(1-x)}Zr_{(x)}O_2$ 촉매 최적화)

  • Jeong, Dae-Woon;Kim, Ki-Sun;Eum, Ic-Hwan;Lee, Sung-Hun;Koo, Kee-Young;Yoon, Wang-Lai;Roh, Hyun-Seog
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.213-216
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    • 2009
  • WGS(Water Gas Shift)반응은 일산화탄소(CO)를 이산화탄소($CO_2$)로 전환하는 반응으로 일체형 수소생산시스템의 실현을 위한 고순도 수소생산에 있어서 중요한 단계이다. WGS 반응은 열역학적 평형을 고려하여 고온전이반응(HTS: High Temperature Shift)과 저온전이반응(LTS: Low Temperature Shift) 두 단계 반응으로 진행된다. 두 단계 공정의 통합을 위해 낮은 온도에서 높은 활성을 갖는 WGS 반응용 촉매 개발이 필요하다. 최근 낮은 온도에서 높은 활성을 갖는 귀금속 촉매에 다양한 담체를 적용시킨 연구가 활발히 진행되고 있다. 선행 연구 결과, Ce-$ZrO_2$ 구조는 Ce/Zr 비에 따라 다양한 특성 변화를 관찰하였다. 따라서 낮은 온도에서 높은 활성을 갖는 WGS 반응용 촉매 제조를 위해 환원성 담체인 $CeZrO_2$에 Pt 을 담지시켜 성능을 평가하였다. 제조된 모든 담체는 공침법(Co-precipitation)으로 제조 하였으며 $500^{\circ}C$에서 6시간 소성하였다. 제조된 담체에 백금(Pt)을 함침법(Incipient Wetness Impregnate)으로 담지시켰다. 특성분석은 BET를 이용하여 표면적을 측정하였다. 촉매 반응 실험조건은 $200^{\circ}C{\sim}400^{\circ}C$ 온도범위에서 기체공간속도(GHSV: Gas Hourly Space Velocity) 45,000 ml/$h{\cdot}g-cat$ 으로 혼합가스($H_2$:60%, $N_2$:20%,$CH_4$:1%,CO:9%,$CO_2$:10%)를 흘려 반응 후 배출되는 가스를 Micro-Gas Chromatography 를 이용하여 측정하였다.

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A Study on the Evolution of the Spatial Organization appeared in Local Government Buildings in Korea (국내 지자체 공공청사의 공간조직 변화과정에 관한 연구)

  • Choi, Yoon-Kyung;Hyun, Chang-Yong
    • Korean Institute of Interior Design Journal
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    • v.20 no.6
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    • pp.36-43
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    • 2011
  • The study presupposes that, ever since its modernization, the Korean local government buildings have undergone an evolutionary process of their spatial organizations and the process can be analyzed in terms of increased publicness of architectural space. For the purpose, fifteen examples of local government buildings in Korea are selected and analyzed in terms of their plans converted into spatial diagrams measuring accessibility depth. Within these analytical diagrams, some quantitative measures such as permeability and visual connection, and the number of decision making points that visitors face on the way to their targets. The study analyzes these analytic measures of selected samples which are categorized into three chronological groups in order to search any evolutionary tendency of spatial transformation. The analysis shows that the accessibility of public functions and presumably the publicness of the spatial organization of local government buildings has been increased. The results of the study implies that, to acquire architectural publicness in government buildings, not only the insertion of public programs but also the organization of open spatial structure is significant.

Numerical Investigation on the Mechanism of Mode Transition in Axi-symmetric Supersonic Jet Screech (축대칭 초음속 제트에서 스크리치 모드 전이현상의 수치적 연구)

  • Bin, Jong-Hoon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.38 no.8
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    • pp.790-797
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    • 2010
  • Mode transition of the axi-symmetric screech tone in the low supersonic Mach number range from 1.0 to 1.20 is numerically analyzed. The axi-symmetric Navier-Stokes equations and the k-e turbulence model are solved in the cylindrical coordinate system. The dispersion-relation-preserving(DRP) scheme is applied for space discretization and the optimized four levels marching method are used for time integration. At low supersonic Mach numbers with an axi-symmetric A1 mode in the simulation, it is shown that acoustic propagation due to the nonlinear effects is seen in the lateral direction and the screech tone frequency is the same as the vortex passing frequency due to the generation of intense large-scale vortical motions.

Case Analysis of the performance contents using virtual reality technology (가상현실 기술을 활용한 공연콘텐츠의 사례분석연구)

  • YOO, YOUNGJAE
    • Journal of the Korea Convergence Society
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    • v.8 no.5
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    • pp.145-153
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    • 2017
  • As success stories of using virtual reality (VR) have become more prevalent, interest in performance-related technology has rapidly increased around the world. Performances such as, Cirque du Soleil had much success in using video technology, these VR applications have enabled experiences using digital image technology. However, critics have claimed that the completeness and diversity of visual content is reduced, due to insufficient storylines, spatial composition, and partial use of the entire visual field. Therefore, the design of a performance using digital image technology should consider the characteristics of the production stage to be different from real world performances. In this study, the visual space of the stage, the method of creating space for the stage, and the movement of the performer and utilization of the performance was analyzed. Through this, It transferred the limitation of the traditional stage into the space and time of the image and opened the possibilities of the tran­-media.

인터넷 중독의 회복 프로그램에 관한 연구

  • Jeong, Gwan-Yong;Byeon, Sang-Hae
    • 한국벤처창업학회:학술대회논문집
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    • 2016.04a
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    • pp.166-168
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    • 2016
  • 본 연구는 인터넷 접속 환경이 유선에서 무선으로 급속히 전환되고 인터넷에 접속할 수 있는 시간과 공간의 제약이 없어지면서 인터넷 중독자 문제가 많은 사회문제를 야기하고 있는 시점에서 인터넷 중독자수 예측 및 중독자 치료 프로그램의 효과를 분석하기 위한 연구이다. 청소년을 대상으로 통계청 추정인구와 공공분문의 통계자료를 바탕으로 중독자 예측 및 회복효과 측정 프로그램을 개발하여 분석하였다. 연구결과 스마트기기의 보급의 확대의 영향으로 청소년 인터넷 중독자 수는 점차 증가하다가 청소년 인구감소의 영향으로 2016년을 기점으로 감소하는 것으로 분석되었다. 중독예방과 치료를 위한 예산 증가 시나리오 분석 결과 인터넷 중독 잠재적 위험과 고위험군에서 모두 효과가 있는 것으로 분석되었고 중독 다음 단계로 전이 되는 것을 예방하는 효과가 있는 것으로 나타났다. 특히 인터넷 중독 고위험 사용자의 전문치료 수준을 강화했을 경우 그 효과가 큰 것으로 나타났다.

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An experimental study on the load transfer machanism of shallow 2-arch tunnel excavation sequence with vertical discontinuity planes in sandy ground (연직 불연속면이 존재하는 얕은 심도의 사질토 지반에서 2-arch 터널 단계별 굴착에 따른 하중전이에 관한 실험적연구)

  • Oh, Bum-Jin;Lee, Sang-Duk
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.13 no.3
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    • pp.215-231
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    • 2011
  • In this study, the behavior of a shallow 2-arch tunnel during the excavation in the sandy ground containing vertical discontinuity plane was experimentally studied. Load transfer mechanism in the pillar caused by a 2-arch tunnel excavation was observed. The position of the vertical discontinuity plane was varied. Model tests were carried out in the normal construction sequence of 2-arch tunnel. Test results-showed that the load transfer caused by the 2-arch tunnel excavation was concentrated in the discontinuity plane, and was cut by the discontinuity plane, so no load transfer took place above the discontinuity plane. It was also shown that the effect of adjacent tunnel excavation on the pillar load and the ground deformation was greater when excavating the upper half-face of the main tunnel, more than when excavating the lower half-face.

Earth pressures acting on vertical circular shafts considering arching effects in c-$\phi$ soils : II. Lab. Model Tests (c-$\phi$ 지반에서의 아칭현상을 고려한 원형수직터널 토압 : II. 실내 모형실험)

  • Kim, Do-Hoon;Cha, Min-Hyuck;Lee, Dea-Su;Kim, Kyung-Ryeol;Lee, In-Mo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.12 no.2
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    • pp.129-144
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    • 2010
  • The earth pressure acting on the vertical shaft is less than that acting on the retaining wall due to three dimensional arching effect. Thus, it might be essential to estimate the earth pressure actually acting on the shaft when designing the vertical shaft. In this paper, large-sized model tests were conducted as Part II of companion papers to verify the newly suggested earth pressure equation proposed by Kim et al. (2009: Part I of companion papers) that can be used when designing the vertical shaft in cohesionless soils as well as in c-$\phi$ soils and multi-layered soils. The newly developed model test apparatus was designed to be able to simulate staged shaft excavation. Model tests were performed by varying the radius of vertical shaft in dry soil. Moreover, tests on c-$\phi$ soils and on multi-layered soils were also performed; in order to induce apparent cohesion to the cohesionless soil, we add some water to the dry soil to make the soil partially-saturated before depositing by raining method. Experimental results showed a load transfer from excavated ground to non-excavated zone below dredging level due to arching effect when simulating staged excavation. It was also found that measured earth pressure was far smaller than estimated if excavation is done at once; the final earth pressure measured after performing staged excavation was larger and matched with that estimated from the newly proposed equation. Measured results in c-$\phi$ soils and in multi-layered soils showed reduction in earth pressures due to apparent cohesion effect and showed good matches with analytical results.