• 제목/요약/키워드: I-projection

검색결과 265건 처리시간 0.026초

보강원통셀의 최적구조설계에 관한 연구 (A Study on the Ooptimization of the Stiffened Cylindrical Shell)

  • 이영신;김대원
    • 대한기계학회논문집
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    • 제13권2호
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    • pp.205-212
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    • 1989
  • 본 연구에서는 축방향 압축력을 받는 단순지지 직교보강원통셸을 구배투영법 (Gradient Projection Method)으로 최적화 하였으며, 이 과정에서 좌굴해석은 확산법 (Smeared-Out Method)으로 수행하였다. 사용한 설계변수는 최대 8개이고, 고려한 제한조건은 좌굴, 응력 및 기하학적 제한조건으로 전체 21개이다.본 연구에서 적용한 설계예는 사각형, I형 및 T형 보강재를 갖는 원통셸이다. 사각형 및 I형의 경우는 기존의 연구결과와 비교하여 본 해석의 유용성 및 정밀도를 입증하고 보강재의 형태에 따른 효율성도 아울러 검토하고자 한다.

p-Phenylenediamine Dihydrochloride의 結晶構造 (The Crystal Structure of p-Phenylenediamine Dihydrochloride)

  • 구정회;민태원;신현소
    • 대한화학회지
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    • 제9권3호
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    • pp.142-147
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    • 1965
  • p-Phenylenediamine dihydrochloride의 結晶構造를 X-線 廻折法을 利用하여 解明하였다. 이結晶은 三斜晶係에 屬하며, 空間群은 $C_i1-P{\bar\1}$ 이고, 格子常數는 $a= 4.38{\pm}0.02, b=5.90{\pm}0.02, c=8.76{\pm}0.03{\AA}, {\alpha}=1101{\pm}1, {\beta}=96{\pm}1^{\circ}$이다. 그리고 單位格子속에는 들어있는 化學單位數,Z는 1이다. 各原子의 座標는 a, b 및 c軸에 따른 二次原的인 電子密度의 投影 및 ($F_o-F_c$) 合成에 依하여 얻었다. 이 結晶構造와 이미 硏究된 aliphatic diamine의 hydrogen halide 들의 構造와를 比較하였다.

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이원 분산성분의 사영분석 (Projection analysis for two-way variance components)

  • 최재성
    • Journal of the Korean Data and Information Science Society
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    • 제25권3호
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    • pp.547-554
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    • 2014
  • 본 논문은 실험자료에 대한 분석모형으로 이원 분산분석모형을 가정한다. 확률효과 모형의 가정하에 분산성분의 추정량을 구하기 위한 방법으로 적률법을 가정하고 있다. 분산성분의 적률 추정방법인 Henderson의 방법 I과 방법 III을 다루고 있다. Henderson의 두 방법에서 소개되는 제곱합 대신에 벡터공간에서의 사영을 활용하는 방법을 제시하고 있다. 또한 제곱합의 기대값 계산을 위해 두 방법 모두 Hartley의 합성법을 제공하고 있으나 본 논문에서는 관련행렬의 고유근을 이용할 수 있음을 제시하고 있다. 분산성분의 해를 얻기 위한 방법의 차이에서 유도되는 연립방정식들은 같지 않으나 양수의 분산성분들에 대한 해는 유사함을 보여주고 있다.

A Sanov-Type Proof of the Joint Sufficiency of the Sample Mean and the Sample Variance

  • Kim, Chul-Eung;Park, Byoung-Seon
    • Journal of the Korean Statistical Society
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    • 제24권2호
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    • pp.563-568
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    • 1995
  • It is well-known that the sample mean and the sample variance are jointly sufficient under normality assumption. In this paper a proof of the joint sufficiency is given without using the factorization criterion. It is related to a finite Sanov-type conditional theorem, i.e., the conditional probability density of $Y_1$ given sample mean $\mu$ and sample variance $\sigma^2$, where $Y_1, Y_2, \cdots, Y_n$ are independently and identically distributed (i.i.d.) normal random variables with mean m and variance $\delta^2$, equals that of $Y_1$ given sample mean $\mu$ and sample variance $\sigma^2$, where $Y_1, Y_2, \cdots, Y_n$ are i.i.d. normal random variables with mean $\mu$ and variance $\sigma^2$.

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PROJECTIONS OF ALGEBRAIC VARIETIES WITH ALMOST LINEAR PRESENTATION I

  • Ahn, Jeaman
    • 충청수학회지
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    • 제32권1호
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    • pp.15-21
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    • 2019
  • Let X be a reduced closed subscheme in ${\mathbb{P}}^n$ and $${\pi}_q:X{\rightarrow}Y={\pi}_q(X){\subset}{\mathbb{P}}^{n-1}$$ be an isomorphic projection from the center $q{\in}{\mathbb{P}}^n{\backslash}X$. Suppose that the minimal free presentation of $I_X$ is of the following form $$R(-3)^{{\beta}2,1}{\oplus}R(-4){\rightarrow}R(-2)^{{\beta}1,1}{\rightarrow}I_X{\rightarrow}0$$. In this paper, we prove that $H^1(I_X(k))=H^1(I_Y(k))$ for all $k{\geq}3$. This implies that Y is k-normal if and only if X is k-normal for $k{\geq}3$. Moreover, we also prove that reg(Y) ${\leq}$ max{reg(X), 4} and that $I_Y$ is generated by homogeneous polynomials of degree ${\leq}4$.

투시도적 표상에서 공간의 투사로 -2차원 그림의 3차원 투사를 활용하는 현대건축의 경향에 대한 연구- (From Perspectival Space to Projected Space -A Study on Architectural Design Using Three Dimensional Projection of Two Dimensional Drawings-)

  • 이상헌
    • 건축역사연구
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    • 제15권3호
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    • pp.27-42
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    • 2006
  • Many contemporary architectural avant gardes tend to use painting as a medium to create architecture which goes beyond the rationalized spatial conception of modem architecture represented by perspectivism. They produce non perspective drawings to represent spatial Ideas, and expand it through poetic imagination to create an unexpected architectural form and space. This paper attempts to analyze the historical origin and background of dominance of drawing in the production of architecture. It was with the invention of perspective that architectural representation became important tool for architectural production. Thereafter, drawing was considered prior to actual building and architecture was considered a three dimensional realization of two dimensional drawing. Modernist avant gardes such as Cubism shattered the rationalized pictorial space of perspective and found a new pictorial space. They tried to extend it to three dimensional space through parallel projection largely based on the Hildebrand's theory of pure visibility. However, due to the ambiguity of the position of the viewing subject, their attempts could not succeed in creating a new architecture. The new architectural avant garde of the 70's rediscovered the early 20th century avant gardes in their attempt to create a new architecture which can register the fragmented spatial condition of contemporary society, and used painting as a medium to create architecture. Their difference from the early avant gardes was that they used poetic imagination rather than parallel projection in the process of projecting three dimensional space and form from the painting. However, their architecture cannot escape the scopic field of perspectivism in that they rely on the picture plane and the distance between object and viewing subject. Therefore, I conclude that in order to create architecture which goes beyond the rationalized space of modern architecture, it is necessary to resort to other tradition of modern architecture than visual one.

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3차원 공간으로 복제된 인간 형상 오브제에 음악과 동기화한 콘텐츠의 매핑 (Mapping of Synchronized Contents with Music to 3 Dimensional Spatial Cloned Human-Object)

  • 배문경;류재하;김상욱
    • 한국콘텐츠학회논문지
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    • 제14권11호
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    • pp.620-627
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    • 2014
  • 현시대의 사회적 환경은 디지털화되고 있으며, 미디어의 발전으로 대중들은 아날로그보다 디지털에 익숙해지고 있다. 그러한 사회 구조 속에서 대두되고 있는 미디어아트는 다양한 작업방식 중에서 프로젝션 매핑방식이 많이 활용되고 있다. 본 연구에서는 'Cloned Me' 작품을 바탕으로 프로젝션 매핑 작품 구현 과정에 대해 논하고자 한다. 음악을 가시화한 영상 콘텐츠를 제작하고 철 구조물 위에 프로젝션 매핑으로 영상 콘텐츠를 투사하는 방식으로 작품이 구현된다. 스토리를 담은 오브제를 제작하고 그 위에 프로젝션 매핑 방식으로 영상 콘텐츠를 투사함으로써 기존의 미디어 파사드와 차별성을 가진다. 오브제와 콘텐츠 사이를 연결하는 스토리와 구성이 존재하고 상호보완적 수정이 용이하다는 것이 장점이다. 프로젝션이 투사되는 면이 사각형의 고정된 프레임에서 벗어나 독특한 구조를 이룬다. 복제가 가능한 디지털 기술이 발전한 현시대의상을 반영해주는 작품이라는 점에서 의의를 지닌다.

인체 골격의 X-ray 투사 이미지를 활용한 패션디자인 (Human Skeletal X-ray Projection Images Applied Fashion Design)

  • 박정인;이연희
    • 한국의상디자인학회지
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    • 제17권3호
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    • pp.13-27
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    • 2015
  • The purpose of this study is to understand the general process from textile design till fashion design and to understand the relation between the body structure by using the x-ray technique. The research method was to see background of the anatomic feature and human skeletal X-ray projection through historical aspect of publications, the Internet, and paper. In terms of production, in order to present a design that takes into account the unique silhouette of the human body without distorting the shape of the human skeleton, X-ray images that were reconstituted using a computer graphic tool (Photoshop CS) were reproduced into the fabric as intense images through the digital Textile Printing technique that is capable of expressing fine and delicate details, and applied into the design. An original design was developed that emphasized the impression of the human body being projected and the shape of the human skeleton realistically expressed in terms of silhouette and detail. The results are as follows: First, Body has a anatomic formative characteristic and its formativeness becomes as a great motive for the artistic expression and thereby it becomes more unique and available for new design expression. Second, Using the 'body frame' as the motive of the research, there's mainly tried to make an unique expression. Third, according to reconstructing human skeletal X-ray projection by using Adobe Photoshop CS2, it can be expressed strong and unique design. Forth, DTP which is being used as an essential technique, expresses the body frame realistically and being used the special type of functional product and silk. Likewise by discovering the diverse formativeness of our body frame and reflecting the sense of humanity into the pieces there's been able to make and develop an unique fashion design. I sincerely hope there is a hug progress in this research in this area.

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ERROR ESTIMATES FOR THE FULLY DISCRETE STABILIZED GAUGE-UZAWA METHOD -PART I: THE NAVIER-STOKES EQUATIONS

  • Pyo, Jae-Hong
    • Korean Journal of Mathematics
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    • 제21권2호
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    • pp.125-150
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    • 2013
  • The stabilized Gauge-Uzawa method (SGUM), which is a second order projection type algorithm to solve the time-dependent Navier-Stokes equations, has been newly constructed in 2013 Pyo's paper. The accuracy of SGUM has been proved only for time discrete scheme in the same paper, but it is crucial to study for fully discrete scheme, because the numerical errors depend on discretizations for both space and time, and because discrete spaces between velocity and pressure can not be chosen arbitrary. In this paper, we find out properties of the fully discrete SGUM and estimate its errors and stability to solve the evolution Navier-Stokes equations. The main difficulty in this estimation arises from losing some cancellation laws due to failing divergence free condition of the discrete velocity function. This result will be extended to Boussinesq equations in the continuous research (part II) and is essential in the study of part II.

컴퓨터그래픽을 이용한 일영작도에 관한 연구 (A Study on the Computer Graphic Protraction on the Solar Shadow Mask)

  • 구현덕;김기세;조일식;송인춘
    • 태양에너지
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    • 제19권2호
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    • pp.9-19
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    • 1999
  • For determining solar benefit hour are two different methods required as a direct calculation which is more accurate but too slow, and a computer graphic protration which is less accurate but too fast. To have the later accurate, the hour to hour interpolation is used to provide less visual deviation. With directly pointing the solar location into the screen coordinate the waldram projection and stereographic projection which needs the number of fast algorithms to calculate the coordinates of the sun path and building configuration casting to the space are applied.

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