• 제목/요약/키워드: Concept formation

검색결과 679건 처리시간 0.037초

Every Single Cell Clones from Cancer Cell Lines Growing Tumors In Vivo May Not Invalidate the Cancer Stem Cell Concept

  • Li, Fengzhi
    • Molecules and Cells
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    • 제27권4호
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    • pp.491-492
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    • 2009
  • We present the result of our research on the tumorigenic ability of single cell clones isolated from an aggressive murine breast cancer cell line in a matched allografting mouse model. Tumor formation is basically dependent on the cell numbers injected per location. We argue that in vivo tumor formation from single cell clones, isolated in vitro from cancer cell lines, may not provide conclusive evidence to disprove the cancer stem cell (CSC) theory without additional data.

Optimization of Space Debris Collision Avoidance Maneuver for Formation Flying Satellites

  • Seong, Jae-Dong;Kim, Hae-Dong
    • Journal of Astronomy and Space Sciences
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    • 제30권4호
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    • pp.291-298
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    • 2013
  • The concept of the satellite formation flight is area where it is actively study with expandability and safety compare to existing satellite. For execution of duty with more safety issue, it needs to consider hot topic of space debris for operation of formation flight. In this paper, it suggests heuristic algorithm to have avoidance maneuver for space debris towards operating flight formation. Indeed it covers, using common software, operating simulation to nearest space environment and not only to have goal of avoidance but also minimizing the usage of fuel and finding optimization for maximizing cycle of formation flight. For improvement on convergence speed of existing heuristic algorithm, it substitute to hybrid heuristic algorithm, PSOGSA, and the result of simulation, it represents the satisfaction of minimum range for successful avoidance maneuver and compare to not using avoidance maneuver, it keeps more than three times of formation maintenance performance. From these, it is meaningful results of showing several success goals like simple avoidance collision and fuel usage and decreasing number of times of maintaining formation maneuver.

Mo/Si 다층박막에서의 고상확산에 의한 실리사이드 생성에 관한 연구 (Silicide Formation by Solid State Diffusion in Mo/Si Multilayer Thin Films)

  • 지응준;곽준섭;심재엽;백홍구
    • 한국진공학회지
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    • 제2권4호
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    • pp.507-514
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    • 1993
  • The solid state reaction of Mo/Si multilayer thin films produced by RF magnetron sputtering technique was examine dusing differential scanning calorimetry (DSC) and x-ray diffraction, and explained in view of two concepts, effective drivig force and effective heat of formation. In constant scanning rate DSC, there were two exothermic peks which corresponded to the formation of h-MoSi2 and t-MoSi2 , respectively. The activation energyfor theformation of h-MoSi2 was 1.5eV , and that of t-MoSi2 was 7.8eV. Nucleation wa stherate controlling mechanism for each of the silicide formation. Amorphous phase was not formed , which was consistent withtheprediction by the concept of effective driving force. h-MoSi2 the first crystalline phase, was considered to have lower interfacial free energy than t-MoSi2 and by increasing temperature it was transformed into more stable t-MoSi2.

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상계해석을 이용한 축대칭 후방압출 공정의 Corner Cavity 해석 (Analysis of the Corner Cavity of Axisymmetric Backward Extrusion by the Upper Bound Approach)

  • 박재훈;변홍석;김영호
    • 한국정밀공학회지
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    • 제17권2호
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    • pp.144-150
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    • 2000
  • In this paper, the formation of a corner cavity in the final stage of axisymmetric backward extrusion process is studied by means of upper bound analysis using kinematically admissible velocity. The quantitative relationships between corner cavity formation and process parameters are studied. And analytical results are compared with those of experiment to which plasticine is used. It is found that the analytical results agree well with experimental one. In addition, to restrict the formation of a corner cavity, driven container is applied to backward extrusion and the results are compared with those of FEM. The critical thickness of the bottom of the billet decreases with increase in reduction of area, and increases with decrease in friction. To prevent the formation of corner cavity, the concept of moving container was applied. Throughout this process, the occurrence of a corner cavity is delayed and forming limit area is enlarged.

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오피스 변화와 새로운 워크스페이스의 방향 (Change in Office Concept and the Direction of Workspace)

  • 이남식;이미숙;김선미;서귀숙
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2007년도 춘계학술대회 논문집
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    • pp.63-66
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    • 2007
  • Rapid social change in economy, society and information technology takes the initiative of changing office formation. It also requires new change in workspace function for the office workers. This research is about the change of office formation chronologically according to the change in economy, society and cultural diversity. The study also shows the directions for the workspace design considering the new demand and flow of the new office formation. Mobile Office, Virtual Office and Moduler Office are the new office formation. Also, the new workspace requires the common space where the workers can communicate diversely and share their knowledge and ideas, enhancing collaboration and productivity of the new workspace.

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기업간 관계형성의 영향요인이 기업성과에 미치는 영향에 관한 연구 -해운서비스 매매기업을 중심으로- (A Research on Impact of the Inter-Firm Relationship Formation Factors upon Business Performance : Primarily on the Ocean Shipping Service Market)

  • 신희철;신한원;최영로
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2004년도 춘계학술대회 논문집
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    • pp.321-332
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    • 2004
  • The purpose of this research is to introduce the concept of "relationship formation factors" in inter-firm relations and to empirically demonstrate that they are effective in improving the relationship results by means of anmediating variable. Therefore, the basic model of this study consists of the independent, mediating, and dependent variables. First, the independent variable, that is, the relationship formation factors, is further classified into three components: transactional, relational, environmental characteristics. Then, the study empirically examines how each of the three components influences the dependent variable, that is, the business performance(Load Factor), by way of the mediating variables, that is, trust and relationship commitment.

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기업간 관계형성의 영향요인이 기업성과에 미치는 영향에 관한 연구 - 해운서비스 매매기업을 중심으로 - (A Research on Impact of the Inter-Firm Relationship Formation Factors upon Business Performance : Primarily on the Ocean Shipping Service Market)

  • 신희철;신한원;최영로
    • 한국항해항만학회지
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    • 제28권5호
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    • pp.373-384
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    • 2004
  • The purpose of this research is to introduce the concept of "relationship formation factors" in inter-firm relations and to empirically demonstrate that they are effective in improving the relationship results by means of an mediating variable. Therefore, the basic model of this study consists of the independent, mediating, and dependent variables. First, the independent variables, that is, the relationship formation factors, are further classified into three components. transactional, relational, and environmental characteristics. Then, the study empirically examines how each of the three components influences the dependent variable. that is, the business performance(Load Factor), by way of the mediating variables, that is, trust and relationship commitment.

전문용어 조어 및 번역 방법론에 대한 시론 (Essay on Terminology Formation and Translation Methodology in Korean)

  • 이현주
    • 비교문화연구
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    • 제31권
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    • pp.331-370
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    • 2013
  • In this knowledge based society, the circulation of knowledge and information is more and more increasing. Terms, as denominations of every specialized concept, has grown in quantity and there are considerable amount of foreign terminology coming to settle down in Korean language. Since terminologies quickly generate and be extinguished, it is important to translate in appropriate way at the very first phase of terminology implementation. This article aims to elaborate the typology of korean terminology translation forms, and propose some guidelines for terminology formation and translation methodology. ISO terminology principle and other institutes' propositions for term formation as well as translational theories constitute two basic columns of the guidelines.

셀제조시스템 설계를 위한 부품-기계 셀의 형성기법 (A Method of Component-Machine Cell Formation for Design of Cellular Manufacturing Systems)

  • 조규갑;이병욱
    • 한국정밀공학회지
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    • 제13권4호
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    • pp.143-151
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    • 1996
  • The concept of cellular manufacturing is to decompose a manufacturing system into subsystems, which are easier to manage than the entire manufacturing system. The objective of cellular manufacturing is to group parts with similar processing requirements into part families and machines into cells which meet the processing needs of part families assigned to them. This paper presents a methodology for cell formation based on genetic algorithm which produces improved cell formation in terms of total moves, which is a weighted sum of both intercell moves and intracell moves. A sample problem is solved for two, three and four cells with an approach based on genetic algorithms.

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가상세계에서의 건강증진교육의 개념분석 (Health Promotion Education In A Virtual World: A Concept Analysis)

  • ;오진아
    • 한국간호교육학회지
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    • 제18권1호
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    • pp.81-94
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    • 2012
  • Purpose: Virtual worlds are emerging in health care as an innovative way of helping clients take responsibility for and promote their own care. Yet, the concept of health promotion education in this environment has not been elucidated. Therefore, we undertook a concept analysis to discover the underlying attributes and contextual basis to generate a conceptual understanding of virtual worlds in the context of health promotion education. Methods: Using Rodgers' evolutionary view of concept development, we analyzed literature on virtual worlds that describe their use to discover critical attributes, antecedents, and consequences of this phenomenon. Eleven studies matching inclusion criteria were reviewed. Results: Analysis of the literature highlighted three areas of important domains: user, simulated environment, and education. This concept analysis extends our understanding of a virtual world for health promotion education. Conclusion: This study may help anticipate future trends in the use of virtual worlds in the context of health promotion education, serving as a stepping-stone for further research on this aspect of the study. The next step should focus on the development of an evaluation tool that can measure the factors identified in this analysis to determine their effects on outcomes and environmental interactions.