• 제목/요약/키워드: Geometrical Figure

검색결과 47건 처리시간 0.027초

전기전도도의 비균질성을 고려한 정밀 두뇌 모형 내부에서 유기되는 유도 전기장 분포해석 (Numerical Analysis of Electric Field Distribution Induced Inside a Realistic Brain Model Considering Conductivity Heterogeneity)

  • 김동훈;이일호;원철호
    • 전기학회논문지
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    • 제57권2호
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    • pp.314-319
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    • 2008
  • In this paper, the electric field distribution induced inside the brain during Transcranial Magnetic Stimulation(TMS) has been thoroughly investigated in terms of tissue heterogeneity and anisotropy as well as different head models. To achieve this, first, an elaborate head model consisting of seven major parts of the head has been built based on the Magnetic Resonance(MR) image data. Then the Finite Element Method(FEM) has been used to evaluate the electric field distribution under different head models or three different conductivity conditions when the head model has been exposed to a time varying magnetic field achieved by utilizing the Figure-Of-Eight(FOE) stimulation coil. The results show that the magnitude as well as the distribution of the induced field is significantly affected by the degree of geometrical asymmetry of head models and conductivity conditions with respect to the center of the FOE coil.

일차변환 관점에서의 도형의 성질 이해 및 학교수학에의 시사점 (Understanding the properties of geometric figures through the linear transformation and its implication for school mathematics)

  • 홍갑주
    • 한국수학교육학회지시리즈A:수학교육
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    • 제47권4호
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    • pp.437-445
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    • 2008
  • On the basis of the meaning and general process of geometric proof through transformation concept and understanding the geometric properties of linear transformation, this study showed that the centroid of geometrical figure and certain properties of a parabola and an ellipse in school mathematics can be explained as a conservative properties through linear transformation. From an educational perspective, this is a good example of showing the process of how several existing individual knowledge can be reorganized by a mathematical concept. Considering the fact that mathematical usefulness of linear transformation can be revealed through an invariable and conservation concept, further discussion is necessary on whether the linear transformation map included in the former curriculum have missed its point.

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직선의 대수적 표현과 직선성(直線性)으로서의 기울기 (Revisiting Linear Equation and Slope in School Mathematics : an Algebraic Representation and an Invariant of Straight Line)

  • 도종훈
    • 한국수학교육학회지시리즈E:수학교육논문집
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    • 제22권3호
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    • pp.337-347
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    • 2008
  • 도형으로서의 직선을 좌표평면에서 대수적으로 표현하는 과정에서 곧음이라는 직선의 고유한 성질은 삼각형의 닮음에 의해 x값의 변화량에 대한 y값의 변화량의 비가 일정하다는 성질로 구체화되고, 이로부터 기울기의 개념이 자연스럽게 등장한다. 이때 기울기는 좌표평면에서 직선의 직선다움 즉, 직선성(直線性)을 나타내주는 수학적 개념으로 서로 평행인 직선을 구분하지 않을 때 한 직선의 불변량이라 할 수 있고, 직선의 방정식은 일정한 비로서의 기울기가 지닌 성질을 대수적으로 표현한 것이라 할 수 있다. 본 논문에서는 좌표평면에서의 직선 및 직선성(直線性)으로서의 기울기 개념이 학교수학에서 어떻게 다루어지고 있는지 분석하고, 개선 방안에 대하여 논의한다.

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접합부 강성과 비대칭 적설하중 적용을 통한 목조 래티스 지붕 구조물의 좌굴하중 특성 (Buckling Load of Lattice Timber Roof Structure considering Stiffness of Connection with Asymmetric Snow Load)

  • 황경주
    • 한국공간구조학회논문집
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    • 제23권1호
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    • pp.69-76
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    • 2023
  • A timber lattice roof, which has around 30m span, was constructed. In order to figure out the realistic buckling load level, the structural analysis of this roof structure was performed especially by stiffness of connection with various asymmetric snow load. Due to the characteristics of application of snow load, the load combinations of snow should be considered not only global area but also local part so that the critical buckling load could be observed as easy as possible. Geometrical imperfection was simulated to consider inaccurate shape of structure. And then nonlinear analysis were performed. Finally, this paper could investigate that the asymmetric snow load with the lower level stiffness of connection decreased the level of buckling load significantly.

항만 경쟁력 평가를 위한 유사도 기반의 이산형 평균 알고리즘 (A Dispersion Mean Algorithm based on Similarity Measure for Evaluation of Port Competitiveness)

  • 추봉성;이철영
    • 한국항해항만학회지
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    • 제28권3호
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    • pp.185-191
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    • 2004
  • 평균법과 클러스터링은 다속성 평가문제에서 널리 쓰이고 있는 중요한 데이터 마이닝 기법들이다. 그러나, 다양한 다속성 평가 문제에서 데이터 마이닝을 할 때, 데이터들의 특징은 그 중요성이 달라질 수 있기 때문에 이러한 데이터의 중요도 차이를 고려해야 할 필요가 있다. 따라서, 이러한 기법들은 데이터의 선택 및 중요도 등과 같이 그 특징을 얼마나 잘 반영하는 지가 중요하다. 게다가, 산술평균법의 경우에는 우선순위 및 가중치로 정의되는 평가구조에서 적합한 결과를 산출하기에는 한계가 있을뿐 만 아니라, 평가자 그룹별 특징을 반영하기 곤란하다. 따라서, 본 연구에서는 기하학적 도형을 바탕으로 유사도를 평가하여, 평가자 그룹별로 특징지어지는 이산적인 환경에서의 평균을 산출하는 알고리즘을 제안하였다. 본 알고리즘의 핵심사항 중 하나는, 항목별 우선순위의 혼돈없이 유사도를 평가할 수 있다는 점이다.

멘디의 역사적 기원과 상징성에 대한 연구 (The Study of the Historic Origin and the Symbolism of Mehndi)

  • 조은영;유태순
    • 한국의류산업학회지
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    • 제6권3호
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    • pp.297-306
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    • 2004
  • Mehndi, becoming a kind of body fashion in western advanced countries nowadays, is a exquisite, classical fashion form sublimated to traditional faith, medicine and designing art. As one of the cultural arts, especially transmitted by women, a individual tradition of the way how to do the mehndi and the design has been handed down from one culture to another over a thousand of years and it is extensively using in many area, all around world today. Mehndi was used as preparing for special events or celebrations in India, Africa, Central Asia in order to pray for happiness, good luck and calm hart 5000 years ago. Especially, it is concerned with romantic love or a wedding and takes important part of a traditional wedding reception and bride adorning in the culture of Hindu or Islam. In addition to adorning skin, mehndi has various symbols, meaning, function, that is, as a speechless language, in several cultures, it has common meaning such as attraction, protection, celebration. The design of mehndi has been in harmony with the figure, colors, skin types of the dress or the ornament. According to the region, religion, design, mehndi is divided into the design of India and Morocco mostly. Indian design mainly shows flowers and paisley pattern, people widely recognize this design to celebrate and adorn bride in wedding ceremony, still apply mehndi the present time. Moroccan mehndi design, representing North Africa, characterized a bold geometrical figure which stands for belief in living under the protection from supernatural power. Through the understanding of these various meaning, function, symbolism of the design, adorning their body, the current general public use mehndi as not only aesthetic means but also another self expression.

패션컬렉션에 나타난 티셔츠의 그래픽디자인에 관한 연구 (A Study of T-Shirt Graphic Designs Shown in Fashion Collections)

  • 김선영
    • 한국의류학회지
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    • 제36권7호
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    • pp.727-740
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    • 2012
  • This study is for the enhancement and utilization of future graphic design for T-shirts and deals with the expression styles and features of T-shirt graphic designs that appear in modern fashion. A literature examination about graphic design and T-shirts was performed for the research method and the analysis followed 378 pieces of graphic design featured in four major international collections for females from 2001S/S to 2011S/S. The research results from the expression type of T-shirt graphic design in the modern fashion are as follows. Expression in graphic figure accounts for the largest portion of 40.8% that includes illustration or cartoon characters, personal figure or part of the physical body, object in daily life or landscape pictures, animals and plants, and others. Expression given in text with typography or logo accounted for 27.5%, expression combined with letter/text, graphics and geometric figures accounted for 24.3%, geometrical expression accounted for 7.4%; most of which are given in print. Characteristics found in modern fashion graphic design are as follows. First, role of sort of public relations marketing was accompanied with utilization of brand logo or symbol. Second, visual play was shown in a sense of humor with diverse graphic figures and playful texts, witty layout with graphic motives, and a free design formation. Third, it denoted a front burner issue delivering the message for various current events or arguments via the way of texts, slogans, and symbolic pictures. Fourth, it depicted artistry through the self-expressive creation of the designer.

실시간 환경에서의 영상조정 및 패치 변경에 의한 축구로봇의 성능개선 (Performance Improvement of Soccer Robot by Vision Calibration and Patch Change in Real Time Environment)

  • 최정원;김덕현
    • 조명전기설비학회논문지
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    • 제23권1호
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    • pp.156-161
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    • 2009
  • 본 논문에서는 카메라 렌즈에서 흔히 발생할 수 있는 렌즈의 왜곡에 의한 화상을 보정하고, 로봇 좌표를 인식하기 위해 사용하는 패치의 변경에 의한 로봇의 위치 및 각도오차를 줄여 축구로봇 시스템의 성능 개선에 대한 새로운 방법을 제시한다. 그리고 렌즈의 왜곡 중 기하학적인 왜곡을 보정하여 로봇의 위치오차를 줄여 실시간 환경인 축구로봇 시스템에 적용한다. 로봇의 인식과 로봇의 좌표 및 방향을 판별하기 위하여 사용하는 패치는 그 모양에 따라 로봇이 가지게 되는 위치오차와 각도오차가 발생하게 된다. 본 논문에서는 개선한 로봇패치에 따른 로봇의 위치 및 각도 오차를 줄이는 방법을 제안하고 실험을 통하여 이를 검증하였다.

현대 헤어스타일에 나타난 Art Deco적 특성 (A Study on the Art-Deco Hair Styles)

  • 김민정;안성관;백선영
    • 한국패션뷰티학회지
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    • 제6권1호
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    • pp.21-27
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    • 2008
  • The purpose of this study was to observe the Art-Deco style art and hair-style. Art-deco design, which was popular in the 20th century, especially in the 1920s and 1930s, actively absorbed new forms, materials, and aesthetic values that come from technological developments and bridged the tradition to new pupblic culture. Art-Deco style art showed and geometrical decoration tendency to meet modem concept and sense. The over all study on back grounds of Art-Deco style and its art works made possible to figure out the summary on formative characteristics of the style such as simplicity, exoticism, vivid colors, and functionalism. These findings suggest that hair styles borrow its characteristics or image from the past style to create new styles. It was found in the development of new hair styles that patterns or geometric motive appearing the Art-D$\acute{e}$eco style are the source of rich design.

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Escape of Lyβfrom Hot and Optically Thick Media

  • Chang, Seok-Jun;Lee, Hee-Won
    • 천문학회보
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    • 제42권1호
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    • pp.33.2-33.2
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    • 2017
  • Symbiotic stars and quasars show strong far UV resonance doublets including O VI 1032 and 1038, which are known to be major coolants of astrophysical plasma with high temperature T > $10^5K$. We investigate the transfer of $H{\alpha}$ and $Ly{\beta}$ in an emission nebula of temperature T ~ $10^5$, where n=2 population is significant. Line photons of $H{\alpha}$ and $Ly{\beta}$ are transferred in the medium through spatial and frequency diffusion altering their identity according to the branching ratios. We adopt a Monte Carlo technique to describe the transfer of $H{\alpha}$ and $Ly{\beta}$ in an emission nebula with a uniform density and a simple geometrical figure. We find that the temperature of the emission nebula is the major controlling parameter to produce a nonnegligible flux of $Ly{\beta}$. In particular, when T exceeds $10^5K$ the number flux ratio may reach ~ 25% with line center optical depth of a few. We discuss the formation of broad $H{\alpha}$ wings from Raman scattering of $Ly{\beta}$ emergent from a hot emission nebula.

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