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The effects of distance learning experiences through an avatar in a virtual world on users' distance teaching efficacy beliefs (가상현실공간에서 아바타를 통한 원격학습이 아바타 사용자의 교수효능감에 미치는 영향)

  • Park, Jung-Hwan;Cheong, Donguk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.4
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    • pp.1644-1651
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    • 2013
  • The purpose of this study was to investigate the influence of distance education experience using users' avatars in virtual reality space on their teaching efficacy belief. There were 9 participants who were enrolled in a course in doctoral program of education department in J University for the study. The first class of six sessions was face to face class on how to use Second Life and the 14 classes of 3 sessions were done in a classroom of Second Life. According to the analysis of reflection notes, interviews, researcher's observations of 5 participants, their experiences of presentation and taking classes in distance education using their own avatars in Second Life had positive influence on participants' teaching efficacy belief in their future working for distance education using avatars of Second Life. The implication of this study is to show some conditions for successful distance education as well as to see the potential of distance education in 3D virtual reality space using avatars. This study will contribute to promote the future study in distance education field.

A Study on a Model of Teacher Education System in u-Learning (u-Learning 시대의 교사양성 체제 모형 연구)

  • Park, Jung-Hwan;Cheong, Dong-Uk;Park, Hyung-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.11
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    • pp.3308-3314
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    • 2009
  • The purpose of this research is to develop a model of teacher education system in u-Learning age. To achieve the purpose, first, the current teacher education system was analyzed. Second, ubiquitous technologies which could be used in future teacher education system were analyzed. Third, functions of ubiquitous technologies supporting communication between the elements of teacher education system were explored based on the analysis of the technologies. Forth, researchers analyzed pre-service teachers' understanding, needs, and demands for the future teacher education system in u-Learning age. The model of teacher education system which is appropriate for u-Learning age was proposed based on the results of analyses. The developed model could help to educate pre-service teachers who will lead the education in u-Learning age.

Effects of Infants' Free Play in Forests on the Development of Their Sociality (숲에서의 자유놀이가 유아의 사회성 발달에 미치는 영향)

  • Boo, Eun-Soon;Oh, Chang-Hong;Cheong, Donguk;Park, Jung-Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.4855-4864
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    • 2013
  • The purpose of this research is to examine the effects of infants' free play in forests on the development of their sociality. The 24 infants of a kindergarten in Jeju city, who is four years old, participated in the research. Participants freely played in forests for two hours at each time according to their own interests and demands, and this play performed twice every week for total 12 weeks. The results are as followed. Firstly, the free play activities in forests improved the infants' sociality. Secondly, the activities improved every sub-factors of the sociality such as cooperativeness, the acceptance of view, the free will, and the interaction. The results indicate that forests provide rich natural objects for infants to create various and new play by themselves. In addition, the free play activities in forests could build good inter-personal relationship through active interaction among the infants and lead positive impact on the development of their sociality.

Analytical Simulation of the Seismic Response of a High-Rise RC Building Model (고층 철근콘크리트 건축구조모델의 지진응답에 대한 해석적 모사)

  • Lee, Han-Seon;Lee, Jeong-Jae;Jung, Dong-Wook
    • Journal of the Earthquake Engineering Society of Korea
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    • v.12 no.5
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    • pp.1-10
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    • 2008
  • A series of shaking table tests were conducted on a 1:12 scale model using scaled Taft N21E earthquake records to investigate the seismic performance of a 17-story high-rise reinforced concrete building structure with a high degree of torsional eccentricity and soft-story irregularities in the bottom two stories. The main characteristics of the behaviors were: (1) a sudden change of the predominant vibration mode from the mode of translation and torsion to the torsional mode after the flexible side underwent a substantial inelastic deformation; (2) an abrupt increase in the torsional stiffness during this change of modes; (3) a warping behavior of the wall in the torsional mode; and (4) a unilateral overturning moment in the transverse direction to the table excitations. In this study, efforts were made to simulate the above characteristics using a nonlinear analysis program, Perform3D. The advantages and limitations are presented with the nonlinear models available in this software, as they are related to the correlation between analysis and test results.

An Experimental Study on the Stability of Inclined Earth Retaining (지주식 흙막이의 안정성에 관한 실험적 연구)

  • Seo, Min-Su;Im, Jong-Chul;Jeong, Dong-Uk;Yoo, Jae-Won;Koo, Young-Mo;Kim, Gwang-Ho
    • Journal of the Korean Geotechnical Society
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    • v.28 no.12
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    • pp.99-110
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    • 2012
  • Inclined Earth Retaining Structure Method (IER method, briefly) is developed in order to improve the existing earth retaining method. In IER method, there are three main structures, front support, back support, and head binding. Especially, back support acts the role that reduces the earth pressure acting on the front support. In this study, the stability according to the installation angle and stiffness of front or back support is analysed by model tests. By the test results, it is known that inclined back support is very effective to reduce the earth pressure acting on the front support. Especially, the effect of the stiffness and installation angle of back support is analysed.

Developing a teaching practice program for pre-service teachers using a virtual space (가상공간을 활용한 예비교사 수업실습 프로그램 개발)

  • Park, Jung-Hwan;Cheong, Dong-Uk;Kim, Young-Tae;Yun, Seong-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.9
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    • pp.3878-3886
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    • 2011
  • The purpose of this research was to develop a teaching practice program using a virtual space for pre-service teachers reflecting the characteristics of both a virtual space and teaching practice. To develop the program, objectives of the developing, methods of a team grouping, conditions for effective practice were analyzed from literature review and preliminary research. In order to evaluate the effects of the constructed program, the program was applied to 99 pre-service teachers of a university in Korea, and the 46 pre-service teachers participated in the evaluating. The results obtained from the evaluation were that the program brought about the positive change of pre-service teachers' cognition on their teaching efficacy. This program is expected to be effectively used in pre-service teacher education program and connected to the field-based teaching practicum.

Application of Flood Inundation Analysis Model for Analysis of Sinchon Area (신촌지역 침수해석을 위한 범람해석모형의 적용)

  • Tak, Yong Hun;Jeong, Dong Wook;Kim, Young Do;Kang, Boosik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2015.05a
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    • pp.412-412
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    • 2015
  • 최근 기후변화 및 이상기후의 발생으로 짧은 시간에 많은 양의 강우가 발생하는 국지적인 기습강우가 빈번히 발생하고 있으며, 급격히 발전하는 도시지역은 토지이용에 따라 불투수지역이 대부분이며, 유출량이 증가하고 도달시간이 줄어들어 내수침수가 빈번히 발생하고 있다. 도시유역의 배수능력은 우수관거 말단부와 연결된 외수에 영향을 받기 쉽고, 복잡하고 긴 형태를 가진 도시유역의 관망분포에 따라 통수능 부족 및 외수에 의한 내수배제의 불량으로 인한 침수피해가 발생하고 있다. 도시유역에서 우수의 유출현상은 대부분 표면 흐름이나 우수관거를 통하여 흐르게 된다. 불투수층이 대부분인 도시유역의 강우에 의한 내수배제는 우수관거에 의존도가 높으며, 도시유역의 침수현상은 인간의 생활 및 사회기반시설 등에 직접적으로 피해를 입혀 막대한 재산피해와 인명 피해를 야기할 수 있다. 실제로, 우리나라의 경우 큰 하천주변으로 많은 도시들이 위치하고 있어 내수배제 불량에 의한 침수피해가 빈번히 발생하고 있으며, 이를 대비하기 위해 강우-유출 해석을 통하여 침수위험지역을 예측하고 홍수 저감을 위한 계획 수립은 매우 중요하다. 이러한 도시유역의 침수를 분석하기 위해서는 관거의 통수능과 월류수 및 지표수의 흐름을 고려한 2차원 해석이 함께 필요하다. 본 연구에서는 과거 침수가 발생하였던 신촌지역에 대하여 침수해석을 위해 범람해석 모형을 적용하였다. 현재 도시유출모의에 많이 사용되고 있는 SWMM 모형을 이용하여 우수관거의 관망해석을 실시하고 관거의 용량을 초과하여 범람한 유량은 범람해석 모형인 FLUMEN 모형을 이용하여 침수 분석을 통해 노면수의 흐름을 분석하여 도시유역의 침수모의 적용성을 검토하였다.

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A Mobile Agent-based Grouping Method for enhancing Performance of Mobile Database Management Systems (모바일 데이터베이스 관리 시스템의 성능향상을 위한 이동 에이전트 기반 그룹핑 기법)

  • Shin, Sung-Oog;Jeong, Dong-Won;Lee, Jeong-Oog;Baik, Doo-Kwon
    • The KIPS Transactions:PartD
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    • v.10D no.3
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    • pp.375-386
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    • 2003
  • A rapid growth of mobile devices and a proliferation of wireless networks lead to changing the existing environment into a mobile environment. Expansion of mobile environment makes a pressing need of mobile databases, and there are several solutions to achieve it. But they still accompany with some problems. Especially, the current synchronization server that manages consistently many mobile database management systems is based on the centralized method to synchronize data between the mobile database systems. It is the major factor that causes the lower performance of the whole system. Furthermore, the fault tolerance has not been considered in the existing systems. Therefore, we suggest the mobile agent-based mobile database system in order to resolve the problems. The system, we propose in this paper, provides the high-performance of the whole system by mobile grouping, and also may support a fault-tolerance management method.

Prediction of the Transient Performance of the Passenger Diesel Engine with Turbocharger using HIL (HIL을 이용한 터보과급기 승용 디젤 엔진의 과도 성능 예측)

  • Chung, Jin-Eun;Jin, Young-Wook;Jeong, Dong-Young;Chung, Jae-Woo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.17 no.5
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    • pp.127-132
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    • 2009
  • The transient performance of the passenger diesel engine equipped with the variable geometry turbocharger was simulated using HIL(hardware-in-the-loop) system. The system consists of engine model as software, and the turbocharger test bench as hardware. The engine model is mean value model which is programmed by the Simulink of the Mathworks. The turbocharger test bench is composed of a blower, some sensors, and DAQ boards. A real time simulation is possible since the operating system based on the real time is included. The results show the good response for the transient characteristics. Therefore this HIL system can be used for development of the new turbocharger effectively.

Primary Pituitary Aspergillosis - Case Report - (원발성 뇌하수체 아스페르길루스증 - 증례보고 -)

  • Lee, Young Kyun;Kim, Jong Tae;Yoo, Kwan Uk;Ahn, Chang Ho;Chung, Dong Sup;Park, Young Sup;Kang, Joon Ki
    • Journal of Korean Neurosurgical Society
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    • v.29 no.11
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    • pp.1514-1518
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    • 2000
  • Aspergillosis is an uncommon form of fungal infection of the central nervous system in immunocompetent patient, especially those involving the pituitary gland. Several cases of pituitary aspergillosis have been reported, but most of them are directly invaded from aspergillosis of sphenoid sinus. In the present case, a woman with primary pituitary aspergillosis had neither evidence of infection of the sphenoid sinus nor immunodeficiency. The patient underwent a transsphenoidal surgery for a presumed pituitary tumor. Histopathology demonstrated typical findings of aspergillosis. Postoperatively, amphotericin-B was administered and Gallium-67 scan was performed. We describe a case of primary pituitary aspergillosis mimicking pituitary tumor.

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