• Composites Research
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• 제22권1호
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• pp.9-14
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• 2009

본 논문에서는 탄소섬유 복합재료의 균열의 위치 및 성장을 감지하기 위하여 브리지 회로 개념이 적용된 전기 전위법을 제안하였다. 중앙 관통 균열을 가진 복합재료 박판 시험편에 두 쌍의 전극을 생성하였으며, 브리지 회로 개념을 적용하여 한 쌍의 전극에 외부 전압을 인가하고 다른 한 쌍의 전극으로부터 출력 전압 변화를 관찰하였다. 실험과 유한요소해석을 통하여 전극의 크기와 간격, 균열의 위치와 크기 및 성장 방향의 영향을 고찰하였다. 검출 가능한 균열의 크기는 전극의 크기 보다는 전극의 간격에 의한 영향이 더 컸으며, 전극의 크기와 간격이 작을수록 균열의 검출 능력이 우수하였다. 또한, 균열 크기가 증가할 수록, 입력 전극과 가까울수록 출력 전압의 변화가 큼을 관찰할 수 있었다.

• 한국실내디자인학회논문집
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• 제21권1호
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• pp.78-85
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• 2012

The relevance between organisms and their external environment covers everything including humans, natural and artificial surroundings, regarding which academic and scientific understanding has continued. Relevant elements established by inter-dependence between humans and environment and the unity of life should be translated from the perspective of a whole, not of unit elements or reduction. That is, a space is formed by its own program and assumes sustainable relevance based on interactions between internal and external spaces, not building an independent system. The present study aims to present the feasibility of a potential mutant space formed by invisible arenas between individuals and evolutionary space formation based on an ecological paradigm Accordingly, this study suggested that evolutionary attributes as the major power source of biological changes could verify the virtual multiplicity of a new space formation, and that the potential form generation of hybrid mutant space of emergence and infinite formative capability could be supported. The suggestions made here will hopefully contribute to extending applicability of evolutionary space generation in the field of space design. To derive the potential mutant forms from biological space, a preliminary study was conducted regarding the characteristics of evolutionary form generation. For the purpose of this study, three evolutionary perspectives of reproduction, mutation (variation) and selection were taken. First, the theory of evolution was defined and characterized. Also, the relevance between the characteristics generated and hybrid mutant space was analyzed to consider relevant characteristics. The present study helped to understand that the hybrid mutant space had an evolutionary space structure based on a biological paradigm. It was also found that the mutant space structure built by mutant polymorphism assumed a systematic correlation between space and environment.

• 유기물자원화
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• 제23권4호
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• pp.11-20
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• 2015

원지반에서의 저품위 석탄층의 생물학적 메탄 생산을 위한 기초연구를 수행하였다. 인도네시아산 갈탄을 시료로 이용하였으며, 조건을 달리하여 BMP(Biochemical Methane Potential) 실험을 수행하였다. 갈탄에 영양물질과 혐기성 슬러지만 제공한 경우, 온도(23, $30^{\circ}C$)나 석탄의 입자크기는 메탄가스 생산에 영향을 주지 않았다. 이는 가용한 용해성 유기물질이 낮기 때문이다. 외부탄소원으로 볏짚을 갈탄에 첨가한 후 BMP 실험을 수행하였으며, 60일간의 BMP 실험 후 볏짚 첨가에 의한 메탄가스 발생량은 94.4~110.4 mL/g VS이었다. BMP 실험 후 갈탄의 발열량은 볏짚 첨가량이 증가할수록 감소하는 경향을 보였다. 이는 볏짚의 혐기성 분해와 함께 갈탄의 분해가 이루어졌음을 의미한다. 따라서 원지반에서의 저품위 석탄층의 생물학적 메탄 생산의 초기 운전 시에 볏짚을 탄소원으로 사용할 수 있다.

• 디지털융복합연구
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• 제16권10호
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• pp.187-197
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• 2018

본 연구는 조직의 창의적인 성과를 높이고 외부 지식의 활용 능력을 높이기 위한 방안으로 기업가정신과 흡수역량(잠재흡수역량, 실현흡수역량), 창의성과의 관계를 실증 분석하고, 그 효과를 밝히고자 한다. 이러한 변수간의 관계를 밝히기 위해 문헌 연구를 통해 연구모형 및 가설을 설정하였고, 경북지역 전자 산업 종사자를 대상으로 설문조사를 통해 487부의 설문지를 활용하여 실증분석을 실시하였다. 연구 결과, 기업가정신은 창의성과에 유의한 영향을 미치는 것을 확인하였다. 또한 기업가정신이 잠재흡수역량, 실현흡수역량을 통해 창의성과에 영향을 미치는 절차적인 효과를 확인하였다. 이러한 연구결과는 외부 지식의 활용을 통해 조직 내 창의성과를 제고하는데 가이드라인을 제공할 수 있을 것이다.

• 대한족부족관절학회지
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• 제1권1호
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• pp.30-37
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• 1997

Pilon fracture is an intraarticular fracture of distal tibia. It is high energy injury with significantly associated soft tissue damage, bone comminution, and articular surface disruption. Until recently, this treatment has followed the AO principles, Because the risk of complications outweighs potential benefits, the principle of a Pilon fracture treatment are changing. Newer techniques using articulated external fixation minimize disturbance of the soft tissue envelope and have decreased these complications. Series of 5 patients with Pilon fracture were treated by articulated external fixator and followed up more than 12 monthes at the Department of orthopaedic surgery, Kang Dong Sacred Heart Hospital, College of medicine, Hallym University. The results were as follows: 1. The type of fracture were type C2(3 cases),type C3(2 cases) according to AO-$M{\ddot{u}}ller$ classification. 2. The clinical results according to functional criteria by Mast and Teipner were good in 4 cases and poor in 1 case, which is an old fracture. 3. Techniques utilizing articulated external fixator were associated with satisfactory results and appeared to significantly decrease the incidence of soft tissue complication, post-traumatic arthritis, osteoporosis, and fibrosis of ankle joint.

• 보건교육건강증진학회지
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• 제26권3호
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• pp.125-135
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• 2009

Objectives: This study attempts to identify and categorize the types of collaboration that community health centers in Seoul planned to form in order to conduct health promotion programs. Methods: A content analysis was performed by reviewing the Phase 4 Community Health Plans for 2007-2010 of the 25 districts in Seoul. Results: In total, 614 cases of collaboration were identified which the community health centers in Seoul had planned for 2007-2010. These cases were grouped into 10 categories of collaboration activities: offering direct services through external venues utilizing external facilities; providing health education materials to partner agencies promoting health messages through media; running committees with collaborators inviting external experts; participating in external events; referring clients to external health services; connecting services; and miscellaneous. These types and cases were compared across community health promotion programs. Conclusion: Collaboration and partnership should be clearly defined for community health research and practice. Further research is needed to investigate the potential gap between plans for collaboration and actual collaboration activities, and to develop Korean models for collaboration building for community health promotion.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.261-261
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• 2007

Wearable and ubiquitous micro systems will be greatly growing and their related devices should be self-powered in order to avoid the replacement of finite power sources, for example, by scavenging energy from the environment. With ever reducing power requirements of both analog and digital circuits, power scavenging approaches are becoming increasingly realistic. One approach is to drive an electromechanical converter from ambient motion or vibration. Vibration-driven generators based on electromagnetic, electrostatic and piezoelectric technologies have been demonstrated. Among various generator types proposed so far, piezoelectric generator possesses considerable potential in micro system. To overcome low mechanical-to- electric energy conversion, the piezoelectric device should activate in resonance mode in response to external vibration. Normally, the external vibration excretes at low frequency ranging 0.1 to 200 Hz, whereas the resonant frequencies of the devices are fixed as constant. Therefore, keeping their resonant mode in varying external vibration can be one of important points in enhancing the conversion efficiency. We investigated the possibility of use of multi-bender type piezoelectric devices. To match the external vibration frequency with the device resonant frequency, the various devices with different resonant frequency were chosen. Under an external vibration acceleration of 0.1G at 120 Hz, the device exhibited a peak-to-peak voltage of 2.8 V and a power of 0.5 mw in resonance mode.

• 전기화학회지
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• 제6권4호
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• pp.250-254
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• 2003

본 연구는 전기화학적 실험측정으로 페라이트계 430스테인레스강 시험편에 인위적으로 틈을 형성시켰다. 부식용액은 IN $H_2SO_4+0.1N\;NaCl$ 전해액을 사용하였고, 각 시험편의 틈의 크기를 달리하였다. 전기화학적 평가방법은 -600mV/5CE에서 정방향으로 +1,200mV/SCE까지 주사속도 600mV/hr로 동전위 분극시험을 실시하여 부식전위, 부동태 전류밀도 등의 부식거동을 분석하였다. 그리고 정전위 분극시험을 실시하여 부동태 구간 전위 -200mV/SCE를 일정하게 인가 한 후, 틈내에 부동태 전류밀도와 틈부식 발생시간을 계측하였다 실험방법에 있어 Microcapillary tube(MCT)를 이용한 방법으로 틈내 각 지점의 전위를 틈 깊이에 따른 틈내부의 전위강하(IR Drop)에 주목하고, 575 430 스테인레스강 금속에 대한 분극특성과 연계하므로써 틈부식의 발생 원인을 '전위의 이동'의 관점에서 규명 하였다.

• Steel and Composite Structures
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• 제21권1호
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• pp.73-91
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• 2016

The use of box columns has been increased due to the rigidity in rigid orthogonal moment resisting frames. On the other hand, the installation and welding of necessary horizontal continuity plates inside the columns are both labor-consuming and costly tasks. Accordingly, in this paper, a new beam-to-box column connection by trapezoidal external stiffeners and horizontal bar mats is presented to provide seismic parameters. The proposed connection consists of eight external stiffeners in the level of beam flanges and five horizontal bar mats in Concrete Filled Tube (CFT) columns. The new connection effectively alleviates the stress concentration and moves the plastic hinge away from the column face by horizontal external stiffeners. In addition, the result shows that proposed connection has provided the required strength and rigidity of connection, so that the increased strength, 8.08% and rigidity, 3.01% are compared to connection with internal continuity plates, also the results indicate that this connection can offer appropriate ductility and energy dissipation capacity for its potential application in moment resisting frames in seismic region. As a result, the proposed connection can be a good alternative for connection with continuity plates.

• 한국IT서비스학회지
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• 제17권3호
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• pp.157-169
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• 2018

This study aims to examine the factors influencing user attitude toward Smart Home service as the demand of Smart Home service is increasing and it somewhat involves privacy risk. To this end, the research model includes five independent variables, trust in service provider, perceived privacy risk, self efficacy, interpersonal influence, and external influence, influencing the attitude toward Smart Home service. So, this study aims to analyze which variable is the most critical and influential among the five factors and suggest the direction of Smart Home industries. This study first reviews the literature on Smart Home services and describes its Korean situation. Data were collected from residents living in a smart apartment complex. The results show that (1) users have a very positive attitude toward Smart Home service in total, (2) trust in service providers, self efficacy, and interpersonal influence positively impact user attitude toward Smart Home service and interpersonal influence is the most influential variable, however, (3) perceived privacy risk and external influence dose not significantly impact it. These results imply that the role of service providers, self efficacy, and interpersonal influence are important factors on the user attitude toward Smart Home service. Finally, the study's findings and limitations are discussed and potential avenues for future research are suggested.