• 제목/요약/키워드: concept of man

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2차원 초음속 추력편향노즐 쉴리렌 가시화 (Schlieren Visualization of the 2-D Supersonic Thrust Vector Nozzle)

  • 정한진;유두환;최성만;장현수
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2011년도 제37회 추계학술대회논문집
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    • pp.575-578
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    • 2011
  • 추련편향 개념은 최신의 초음속 전투기에 적용되어 사용되고 있다. 본 연구는 추력편향노즐의 성능특성을 쉴리렌기법을 이용한 충격파 가시화를 통하여 제시한다. 피치 각 변화와 피치플랩길이 변화라는 추력편향노즐의 기하학적인 특성에 따른 실험평가를 수행하고, 이러한 연구를 통하여 추력편향노즐의 초음속 유동특성을 분석하였다. 추력편향노즐의 총 추력은 편향각도가 증가함에 따라 감소되며, 추력손실이 가장 적으면서 적절한 편향 효과를 가지는 최적의 플랩 길이비가 존재한다.

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차량 네트워크 시스템의 결함 허용을 위한 IEEE 1451 기반 중복 CAN 모듈의 구현 (Implementation of IEEE 1451 based Dual CAN Module for Fault Tolerance of In-Vehicle Networking System)

  • 이종갑;김만호;박지훈;이석;이경창
    • 제어로봇시스템학회논문지
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    • 제15권7호
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    • pp.753-759
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    • 2009
  • As many systems depend on electronics in an intelligent vehicle, concern for fault tolerance is growing rapidly. For example, a car with its braking controlled by electronics and no mechanical linkage from brake pedal to calipers of front tires(brake-by-wire system) should be fault tolerant because a failure can come without any warning and its effect is devastating. In general, fault tolerance is usually designed by placing redundant components that duplicate the functions of the original module. In this way a fault can be isolated, and safe operation is guaranteed by replacing the faulty module with its redundant and normal module within a predefined interval. In order to make in-vehicle network fault tolerant, this paper presents the concept and design methodology of an IEEE 1451 based dual CAN module. In addition, feasibility of the dual CAN network was evaluated by implementing the dual CAN module.

Design of a Nuclear Reactor Controller Using a Model Predictive Control Method

  • Na, Man-Gyun;Jung, Dong-Won;Shin, Sun-Ho;Lee, Sun-Mi;Lee, Yoon-Joon;Jang, Jin-Wook;Lee, Ki-Bog
    • Journal of Mechanical Science and Technology
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    • 제18권12호
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    • pp.2080-2094
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    • 2004
  • A model predictive controller is designed to control thermal power in a nuclear reactor. The basic concept of the model predictive control is to solve an optimization problem for finite future time steps at current time, to implement only the first optimal control input among the solved control inputs, and to repeat the procedure at each subsequent instant. A controller design model used for designing the model predictive controller is estimated every time step by applying a recursive parameter estimation algorithm. A 3-dimensional nuclear reactor analysis code, MASTER that was developed by Korea Atomic Energy Research Institute (KAERI), was used to verify the proposed controller for a nuclear reactor. It was known that the nuclear power controlled by the proposed controller well tracks the desired power level and the desired axial power distribution.

The Demographic Faultline Is a New Situational Factor for Team Management: The Effect of Leader Teamwork Behaviors on Support for Innovation

  • Na, Dong Man;Park, Seong Hoon;Kwak, Won Jun
    • The Journal of Asian Finance, Economics and Business
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    • 제5권4호
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    • pp.149-160
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    • 2018
  • An alternative method for team diversity studies is to examine demographic faultlines. A concept of demographic faultline enables us to better understand team dynamics with multidimensional diversity. This study suggests the demographic faultline as a new situational factorto influence the relationship between leader teamwork behaviors and a climate of support for innovation. When subgroups divided by demographic faultline are homogeneous within them and heterogeneous between them, the homogeneity may increase intimacy in each subgroup while the heterogeneity may increase exclusiveness between those subgroups. We argued that a leader could play an important role to build a cooperative relationship between faultline-based subgroups and highlight positive aspects of developing and maintaining subgroups in organizations. With a sample of 81 teams (558 employees), it was examined how leader teamwork behaviors would affect a team-level climate of support for innovation and how this relationship would be moderated by each team's demographic faultline (gender, age, and educational specialty). As predicted, it was found that there was a significant positive relationship between each leader's teamwork behaviors and each team's climate of support for innovation. In addition, this relationship was stronger for teams with strong faultline than with weak faultline. Our findings and their implications were further discussed.

파라미터 해석을 통한 차량 성능 예측 기법 연구 (Study on the Prediction Technique of Vehicle Performance Using Parameter Analysis)

  • 김기창;김찬묵;김진택
    • 한국소음진동공학회논문집
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    • 제20권11호
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    • pp.995-1000
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    • 2010
  • With the development of the auto industry, the automobile manufacturers demand to shorten development period and reduce the cost. Compared with the traditional method, applying the virtual prototype is more economical. This paper presents a method for parameters sensitivity analysis and optimizing the performance of vehicle noise and vibration. The existing design processes were repeatedly analyzed with a focus on vehicle performance to decide the design parameters of dimension, thickness, mounting type of body and chassis systems in the vehicle development period. This paper describes the prediction technique of vehicle performance using L18 orthogonal array layout, quality deviation analysis and parameter sensitivity analysis for robust design. This paper analyzed the performance correlation equation through the frequency and sensitivity database according to a design factor change. The new concept is that the performance prediction is possible without repeated activities of test and analysis. This paper described the parameter analysis applications such as bush dynamic stiffness and bush void direction of rear suspension. Design engineer could efficiently decide the design variable using parameter analysis database in early design stage. These improvements can reduce man hour and test development period as well as to achieve stable NVH performance.

건설 정보 활용을 위한 메타데이터 연구 (A Study on Metadata for Using Construction Information)

  • 김진만;황두원;송영웅;최윤기
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2007년도 정기학술발표대회 논문집
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    • pp.848-852
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    • 2007
  • 최근 국내 건설기업에서는 다양한 정보의 수요가 발생하고 있으며 정보량도 점차 증가하고 있다. 그러나 정보량이 방대하여 정확하고 민첩한 정보검색 및 활용이 낮은 상태이다. 효과적인 검색과 활용을 위하여 다양한 분야에서 새로운 검색 모형으로써 각종 메타데이터가 제안되고 있으나 국내${\cdot}$외 건설 산업에서는 일부 기관에서만 활용되고 있는 실정이어서 메타데이터를 이용한 건설정보 활용 연구가 마련되어야 한다. 본 연구에서는 건설 정보의 활용을 위한 메타데이터 분석 연구를 위해 건설 산업의 정보와 정보화 현황, 메타데이터의 개념과 관련연구를 고찰하였다. 그리고 건설정보 활용 현황 및 메타데이터 활용 방안을 분석하고 메타데이터의 시스템 모형과 정보시스템 구축절차를 제시하였다. 이에 초기 연구로써 건설 산업의 메타데이터 요소를 분석하였으며, 메타데이터 적용 시 효과를 제시하였다.

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고공풍력 발전용 시제품 Kite 비행체 개발 (Prototype Kite Development for Wind Power Generation)

  • 권재욱;김종철;문상만;최지웅
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2012년도 추계학술대회
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    • pp.259-260
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    • 2012
  • 본 논문은 저탄소사회 구현을 위해, 신재생에너지원에 관심을 갖고 있는 요즘에, 고공풍력을 이용하여 발전을 할 수 있는 Kite 자동비행에 대한 연구내용이다. 기존의 Kite Sport와 비행기술의 원리를 응용하여, 우선적으로 시제품을 설계/제작하여 시험비행 중이다. 첫 단계로는 RC 조종을 기반으로 한 수동비행제어에서도 Kite의 비행제어가 가능한지의 여부판단이 목적이고, 이를 통한 향 후, 자동비행제어 조건의 설계를 위해 필요로 하는 시험데이터 확보에 초점을 두었다. 현 시제품의 Kite 비행체 내부 구성과 시험내용을 보여주고 있으며, 향 후, 진행방향과 Kite를 통한 에너지활용 측면에서, 해양산업 및 생태문화 보존을 위한 도서지역의 전원공급에 대한 언급을 서술하였다.

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발도르프 수학교육 방법을 적용한 우리나라 대안학교 기하단원 교수·학습에 관한 사례연구 (A Case Study of Geometry Teaching and Learning based on Waldorf Education Methods in a Korean Alternative School)

  • 송만호;김영옥
    • East Asian mathematical journal
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    • 제30권2호
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    • pp.197-222
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    • 2014
  • The purpose of this research is to find out if it is possible to apply the Waldorf School's mathematics education method to Korean alternative schools which are run under the national curriculum. To achieve this, the researcher conducted class on geometry for three weeks with ten 7th graders(four girls and six boys) from Apple Tree Waldorf alternative school in Busan, which has adopted Valdorf education courses. For the first two weeks, the class was about 'fundamental geometrical construction', and then it was evaluated. On the third week, the lesson was on plane figures, followed by a test with 9 plane figure questions that are based on general middle school mathematics curriculum. The result shows that most of the students understood 'fundamental geometrical construction'. When it comes to the test on 'plane figures', seven students got 8 out of 9 right, two students got 6 out of 9 right, and one of them had difficulty solving the questions. According to the results of this research, it is thought that there will be no problem for students to understand mathematical concept even if the Waldorf School's mathematics education method is applied to Korean alternative schools. Also, the Waldorf School's mathematics education method is considered to be a good teaching model for the Korean mathematics curriculum which places emphasis on 'mathematical creativity' in regard to the curriculum and contents.

온톨로지 기반 메타데이터 명명 규칙에 관한 연구 (A Study on the Naming Rules of Metadata based on Ontology)

  • 고영만;서태설
    • 정보관리학회지
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    • 제22권4호통권58호
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    • pp.97-109
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    • 2005
  • 본 연구에서는 정보자원의 메타데이터 작성시 메타데이터 간 의미의 일관성을 유지하기 위한 메타데이터 명명 방법론과 이를 실제 분야에 적용할 수 있는 메타데이터 명명 규칙의 실험적 모형을 제시하였다. 이를 위해 우선적으로 ISO/IEC 11179에서 제시하고 있는 메타데이터 레지스트리 메타모형과 데이터의 기본 속성 및 개념을 논의하였으며, 이러한 논의를 토대로 객체용어(object term)와 속성용어(property term) 및 표현(presentation)에 관한 명명 규칙의 실제 적용 사례를 제시하였다. 객체용어의 생성은 자료유형의 엔터티-관계(I-R) 모형에 근거한 휴리스틱 분석을 통해 이루어졌으며, 속성용어의 명명은 더블린코어의 메타데이터 셋을 기반으로, 표현은 SHOE 1.0 버전을 기반으로 하였다.

우리나라 역대 초등학교 교과서에서 다루어진 '지구과학' 영역의 중심개념과 탐구활동 분석 및 차기 교과서 개선 방안 모색 (An Analysis of Concepts and Inquiry Activities related to the 'Earth Science' Area in the South Korean Elementary School Textbooks to the Current & A Study on the Improvement of Future Textbook)

  • 임성만
    • 한국초등과학교육학회지:초등과학교육
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    • 제34권3호
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    • pp.288-296
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    • 2015
  • This study aimed to analysis of concepts and inquiry activities related to the 'Earth Science' area in the South Korean elementary school textbooks to the current and to seek the improvement of future textbook. For the study, we were collected South Korean elementary school textbooks to the current. After the collection had been made, we were analyzed related to the 'Earth' area in the South Korean elementary school textbooks and were extracted central concepts and inquiry activities. The result of this study: First, there were 'A change in the land', 'Strata and Fossil', 'Volcanoes and Earthquakes', 'Earth and Moon', 'The weather', 'The Solar system and the Star', and 'Seasonal Change' in the central concepts related to the 'Earth' area in the South Korean elementary school textbooks to the current. Second, central concepts were almost the same but the curriculum was changed. Third, inquiry activities also were confirmed to be maintained with little change. This result was believed that it can provide a variety of suggestions at this point in changing the curriculum.