• 대한물리치료과학회지
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• 제15권3호
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• pp.65-72
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• 2008

Background : The purpose of present study was to investigate the effect of quadriceps femoris taping in normal gait using 3D motion capture technique. Method : Twenty healthy volunteers, have no musculoskeletal problems, were recruited as subjects for this study. In experimental group, 20 healthy young(males 10 and females 10) were included. The subjects were assessed during two conditions: control tape(no muscle stretched) and quadriceps (muscle stretched)taping application. To obtain the dynamic data, we captured the motion of subject attached markers without taping during repeated gaits five times or more in 7 m Capture volume of gait analysis center. The result was obtained as a mean value in three times. After taping on quadriceps femoris, the same procedure was carried out. Statistical analysis were performed using statistical software packagess SPSS WIN 12.0(SPSS, Chicago, IL, USA). Differences were tested for statistical significance using paired t-test, independent t-test, chi-squared test for comparisons between the muscle stretched and no muscle stretched. Results : The date of 20 subjects who carried out the whole experimental course were statistically analyzed. 1. gait velocity was showed that muscle stretched group had more significantly increased than no muscle stretched group(p<.05). 2. step length was showed that muscle stretched group had more significantly increased than no muscle stretched group(p<.05). 3. cadens was showed that muscle stretched group had more significantly increased than no muscle stretched group(p<.05). Conclusion : kinesio taping on quadriceps femoris promoted cadence, gait velocity, step length in normal subject (muscle stretched) group.

• Advances in nano research
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• 제12권1호
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• pp.101-115
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• 2022

Some researchers pointed out that the nonlocal cantilever models do not predict the dynamic softening behavior for nanostructures (including nanobeams) with clamped-free (CF) ends. In contrast, some indicate that the nonlocal cantilever models can capture the stiffness softening characteristics. There are substantial differences on this issue between them. The vibration analysis of porosity-dependent functionally graded nanoscale tubes with variable boundary conditions is investigated in this study. Using a modified power-law model, the tube's porosity-dependent material coefficients are graded in the radial direction. The theory of nonlocal strain gradients is used. Hamilton's principle is used to derive the size-dependent governing equations for simply-supported (S), clamped (C) and clamped-simply supported (CS). Following the solution of these equations by the extended differential quadrature technique, the effect of various factors on vibration issues was investigated further. It can be shown that these factors have a considerable effect on the vibration characteristics. It also can be found that our numerical results can capture the unexpected softening phenomena for cantilever tubes.

• Korean Chemical Engineering Research
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• 제50권4호
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• pp.654-658
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• 2012

본 연구에서는 두 개의 기포유동층반응기로 구성된 연속공정에서 고체 흡수제의 입자분석을 이용하여 재생반응기 유동화 기체로 사용된 수분 주입량에 따른 H2O 전처리 효과에 대해 규명하였다. 또한 재생반응기의 고체 배출 구조를 underflow 형태에서 overflow 형태로 수정하여 $CO_2$ 회수효율을 비교 분석하였다. 재생반응기의 유동화 기체로 사용된 수분의 주입량에 따른 고체흡수제의 전처리 효과를 알아보기 위하여 각각의 조업변수에서 포집된 고체입자를 XRD(X-ray Diffraction), SEM (Scanning Electron Microscope), TGA 분석을 수행하였다. XRD 분석을 이용한 결과 재생반응기의 유동화 기체로 주입된 수분에 의해 $K_2CO_3{\cdot}1.5H_2O$의 입자구조가 형성됨을 확인하였으며 TGA 분석에서는 재생반응기로 주입된 수분량에 따라$K_2CO_3{\cdot}1.5H_2O$의 입자구조가 증가하는 경향성을 나타냈다. 재생반응기 내부에서 형성된 $K_2CO_3{\cdot}1.5H_2O$의 입자구조는 흡수반응 시 $CO_2$와의 반응성을 증가시켜 $CO_2$ 회수효율이 향상되는 전처리 효과를 나타내었다. 또한 재생반응기 고체 배출 구조를 underflow 형태에서 overflow 형태로 수정하여 $CO_2$ 회수효율을 비교 분석한 결과 약 3~8% 증가함을 확인하였다.

• 한국콘텐츠학회논문지
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• 제7권8호
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• pp.102-108
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• 2007

디지털 시대를 맞아 21세기 주목받는 문화산업 중에서도 가장 대표적인 게임산업은 최근 어느 때 보다도 그 관심도가 높아지고 있다. 2D 및 3D 애니메이션은 컴퓨터 기술의 발전과 더불어 보다 사실적인 동작표현에 맞추어 계속적인 성장과 발전을 이루고, 컴퓨터 하드웨어 및 소프트웨어 기술의 빠른 변화를 통하여 2D 및 3D 애니메이션 활용범위는 TV, 영화, GAME 산업 등에서 그 영역을 넓히고 있는 추세이다. 한편으로 최근 게임 그래픽의 추세는 2D의 단순조작 게임 중심에서 플레이어의 몰입감과 조작감을 높이는 3D 게임 그리고 3D 게임 캐릭터의 활성화로 2D에서 3D로 그 무게가 변화하고 있는 추세이다. 본 논문에서는 3D 게임 캐릭터의 실사움직임(Motion Capture)과 3D 캐릭터 애니메이션의 종류별, 형태별 모델분류를 하는데 그 의의를 두고 있다. 이를 위해 먼저 3D 게임 캐릭터의 개요 및 실사움직임 사례에 대해 알아보고, 그리고 3D 게임 캐릭터 애니메이션의 종류별 모델 분류, 형태별 모델 분류 데이터를 제안함으로써 향후 게임산업 및 디지털 콘텐츠 산업에 효율성이 높고 빠른 시간에 적용 가능한 캐릭터애니메이션 제작과정 및 3D 캐릭터 애니메이션 응용에 그 효과가 클 것으로 사료된다.

• 한국통신학회논문지
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• 제18권7호
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• pp.989-998
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• 1993

랜덤다원접속 방식인 알로아는 간헐적인 패켓 전송 환경에서 기존의 고정할당 기법보다는 높은 효율을 얻을 수 있다. 그러나 슬롯형 알로아에서는 패켓이 채널에 슬롯별로 할당되기 때된에 슬롯과의 동기화가 중요한 문제가 된다. 위성 통신에서 동기화가 이루어지지 못한 패켓은 인접슬롯의 패켓과 충돌하므로 이러한 문제점을 해결하기위해 슬롯 사이에 보호시간이 포함된다. 기존의 알로아 채널에서는 두개 또는 =1이상의 패켓이 한 슬롯에 동시에 도착될 때 충돌이 발생되고 충돌된 패켓은 모두 재전송 알고리듬에 따라 다시 전송된다. 그러나 무선 환경에서 사용자들은 각각 다른 거리에서 채널을 공유하기 때문에 신호 전력은 달라진다. 실제적으로 신호점유 현상이 존재해서 동시에 수신된 패켓들 중에서 전력이 가장 큰 패켓이 선택되어 모든 패켓이 재전송 될 필요가 없다. 한편 대역확산 다원접속 방식에서는 가장 빨리 도착한 패켓이 선택된다. 본 논문에서는 보호시간과 신호점유 현상을 동시에 고려하여 백로그 상태변화를 추적하는 마르코프 모델로부터 수식적으로 정확한 슬롯형 알로아의 전송효율을 유도한다.

• 수산경영론집
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• 제38권1호
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• pp.71-96
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• 2007

This study is aimed to investigate how the structure of Korean and Chinese fisheries has been changed since the Fisheries Agreement between Korea and China came into effect. This investigation was accomplished from a comparative point of view by using statistic data in the literatures published by both Korea and China. Results of this study are summarized as follows; First, it was revealed that the decreasing rate of fish production of marine capture fisheries in Korea was lowered more by 5.1%, while it was decreased by only 0.1% in China. Second, comparative results on changes in production of offshore fisheries showed that the production of Korean offshore fisheries in 2003 was reduced by 26% compared to that in 1999, while the production of China offshore fisheries was decreased by 22%. In addition, although the production of marine capture fisheries in the East region of China was reduced by 10%, on the contrary, the production of marine capture fisheries in Liaoning, Hebei, Tianjin, Jiangsu, Zhejiang, and Fujian that have mostly impacted by the Korea-China Fisheries Agreement was increased by 7%. Third, results on fishing capacity of marine fisheries indicated that the number of vessels and total horse power in Korea were increased by 1.2% and 44.9%, respectively, while total tonnage was reduced by 23.9%, For China, the number of vessels and total horse power were increased by 0.5% and 12.6%, respectively. Total tonnage was also increased by 11.7%. Finally, the production per Korean vessel was decreased by 17.8% in 2003 compared to that in 1999. On the contrary, the production per Chinese vessel was increased by 8.1% in 2003. The production per tonnage was increased by 3.2% in Korea, while it was reduced by 2.7% in China. In conclusion, it could be said that the Korea-China Fisheries Agreement has had a positive impact on the fisheries production of China, while it has had a negative impacts on that of Korea, relatively.

• 시스템엔지니어링학술지
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• 제9권2호
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• pp.23-36
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• 2013

Plant industry is one of technology-intensive and most prosperous industries in Korea because of its recent prosperity and promising outlook in export. However, no Korean EPC company has yet been well prepared in lifting their capacity sufficient enough to get the upstream conceptual or basic design and engineering orders for sizable plant projects which are known as the more value-added. If systems engineering, a methodology which developed complex systems such as airplanes and has been justified its effectiveness in Defense and NASA projects, can be integrated with plant engineering which should be developed and applied based on the requirements of so many stakeholders, conditions, lifecycle concepts, and constraints of the projects, huge synergic effect is expected particularly in developing a specific upstream design, which is a conceptual or basic design. The notion of integration with each other between systems engineering and plant engineering can be really the crux of EPC's success in any plant projects. This paper suggests an approach showing a methodology how to dig out, analyze, evaluate, verify and implement the stakeholders' requirements into a plant design in conceptual phase using the theory and skills of systems engineering. ISO/IEC 15288 well known systems engineering standards is used. Carbon capture system is used for a case study, for it is an emerging technology in reducing emissions of carbon dioxide causing global warming from flue gas after combustion. Here systems engineering was proven to play a substantial role in enhancing the capability of designers in developing a conceptual design of whole plant or certain part of crucial plant systems.

• 한국수소및신에너지학회논문집
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• 제24권5호
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• pp.428-436
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• 2013

Attrition characteristics of $CO_2$ absorbents for pre-combustion $CO_2$ capture were investigated to check attrition loss of those absorbents and to determine solid circulation direction and the better $CO_2$ absorbent. The cumulative attrition losses of two absorbents increased with increasing time. However, attrition loss under a humidified condition was lower than that under a non-humidified condition case. Between two absorbents, attrition loss of PKM1-SU absorbent was higher than that of P4-600 absorbent. The average particle sizes of the attrited particles were less than $2.5{\mu}m$ for two absorbents under a non-humidified condition case, and therefore, we could conclude that the main mechanism of attrition for two absorbents is not fragmentation but abrasion. Based on the results from the test for the effect of humidity on the attrition loss, we selected solid circulation direction from SEWGS reactor to regeneration reactor because the SEWGS reactor contains more water vapor than regeneration reactor. Attrition loss and make-up rate of two absorbents were compared based on the results from $CO_2$ sorption capacity tests and attrition tests. Required make-up rate of P4-600 absorbent was lower than that of PKM1-SU absorbent. However, more detail investigation on the optimum regeneration temperature, manufacturing cost, solid circulation rate, regeneration rate, and long-term sorption capacity should be considered to select the best $CO_2$ absorbent.

• 한국산학기술학회논문지
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• 제16권10호
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• pp.6439-6444
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• 2015

지구온난화 방지를 위해 이산화탄소를 제거하는 다양한 방법 중 이산화탄소 포집 및 저장 기술이 가장 유망한 기술로 부각되고 있다. 이산화탄소 포집 및 저장기술이 상용화되기 위해서는 저가의 효율적인 흡수제 개발이 필수적이다. 본 연구에서는 금속 나노입자를 이용하여 이산화탄소 흡수속도를 촉진하는 연구를 수행하였다. 코발트, 아연, 니켈의 세 가지 금속나노입자를 합성하였으며 나노입자 합성 방법 중 습식법과 건식법에 의한 영향을 비교 분석하였다. pH 변화를 이용한 이산화탄소 흡수 속도 측정 결과 습식법으로 제조한 니켈 금속나노입자가 가장 우수한 이산화탄소 흡수 속도 촉진효과를 보였다. 금속 나노입자를 이산화탄소 포집공정에 적용할 경우 흡수탑의 크기를 작게 하여 경제적인 공정 구현이 도움이 될 것으로 기대된다.

• 터널과지하공간
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• 제26권1호
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• pp.12-23
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• 2016

향후 국내에서 수행될 이산화탄소 지중저장 프로젝트의 성공적인 수행을 위해서는 현장 지질조건에 최적화된 주입 조건을 설계하는 것이 중요하다. 따라서 본 연구에서는 주입량 및 주입온도 등의 주입조건이 격리저장시스템의 역학적 안정성에 미치는 영향을 열-수리-역학 연계해석기법의 하나인 TOUGH-FLAC 해석기법을 이용하여 평가하였다. 저장시스템의 역학적 안정성은 기존 균열의 전단미끄러짐 발생가능성을 활동마찰각 및 응력원을 이용하여 분석하였다. 이산화탄소의 주입온도가 저류층의 초기온도보다 낮은 저온주입의 조건에도 열응력으로 인한 인장균열은 발생하지 않는 것으로 파악되었으나, 저류층에서 전단미끄러짐이 발생하는 결과를 보였다. 단위시간당 이산화탄소 주입량을 변화시킨 시나리오 해석에서는 단계별로 주입량을 감소시키는 주입시나리오에서 기존 균열들의 전단미끄러짐 발생 가능성이 가장 낮은 것으로 평가되었다.