• 제목/요약/키워드: Three-Dimension

검색결과 1,430건 처리시간 0.028초

쌍생아의 치열궁크기에 관한 유전학적 연구 (A GENETIC SRTUDY ON THE DIMENSION OF DENTAL ARCHES IN TWINS)

  • 김남일;양정강;김만수
    • 대한치과의사협회지
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    • 제9권1호
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    • pp.43-48
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    • 1971
  • The purpose of this study is to evaluate the influence of genetics of the dimensions of dental arches in twins. Thirty-four pairs of Korean twins, of which twenty-three were monozygotic and eleven dizygotic, participated in the study. The twins ranged in age from 6 years to 12 years with mixed dentition. The results were as follows: 1) No significant differences were observed between male and female in mean interpair diffenences of monozygotic twins. 2) Mean interpair differences of monozygotic twins were lesser than these of dizygotic twins. 3) Highly significiant zygotic differences were observed in the mean interpair differences of the width of upper and lower dental arch. This suggest that there is a significant component of hereditary variability.

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삼차원 공간상에서의 질적인 삼각화에 관한 연구 (On Quality Triangulation in Three-Dimensional Space)

  • 박준영
    • 대한산업공학회지
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    • 제23권1호
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    • pp.215-222
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    • 1997
  • This paper deals with the problem of generating a uniform tetrahedral mesh which fills a 3-D space with the tetrahedra which are close to the equilateral tetrahedra as possible. This problem is particularly interesting in finite element modeling where a fat triangulation minimizes the error of an analysis. Fat triangulation is defined as a scheme for generating an equilateral triangulation as possible in a given dimension. In finite element modeling, there are many algorithms for generating a mesh in 2-D and 3-D. One of the difficulties in generating a mesh in 3-D is that a 3-D object can not be filled with uniform equilateral tetrahedra only regardless of the shape of the boundary. Fat triangulation in 3-D has been proved to be the one which fills a 3-D space with the tetrahedra which are close to the equilateral as possible. Topological and geometrical properties of the fat triangulation and its application to meshing algorithm are investigated.

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알루미늄 합금 피로 스트라이에이션의 나노 스케일 관찰 (Nano-Scale Observation of Fatigue Striations for Aluminum Alloy)

  • 최성종;권재도
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집A
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    • pp.153-158
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    • 2000
  • Atomic Force Microscope (AFM) was used to study cross sectional profiles and dimensions of fatigue striations in 2017-T351 aluminum alloy. Their widths (SW) and heights $(SH,\;SH_h)$ were measured from the cross sectional Profiles of three-dimension AFM images. The following results that will be helpful to understand the fatigue crack growth mechanism were obtained. (1) Coincidence of the crack growth rate with the striation width was found down to the growth rate of $10^{-5}$ mm/cycle. (2) The relation of $SH={\alpha}(SW)^{1.2}$ was obtained. (3) The ratio of the striation height to its width SH/SW and did not depend on the stress intensity factor range ${\Delta}K$ and the stress ratio R. From these results, the applicability of the AFM to nano-fractography is discussed.

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A Study on Consumer Value and Corporate Social Responsibility Distribution Activities

  • Lee, Jae-Min
    • 유통과학연구
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    • 제17권4호
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    • pp.17-26
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    • 2019
  • Purpose - Today's companies concentrate intensively on building consumer value and corporate reputation for continuing growth and advancement in an ever-changing global business management environment. This research intended to study the correlation between consumer value and corporate social responsibility (CSR) activities in building corporate reputation with consumers. Research design, data, and methodology - Online and offline surveys were conducted among male and female adults across Korea. Surveys were conducted for three weeks from August 21, 2018 to September 8, 2018. The samples consisted of 350 offline and 112 online surveys, and a combined total of 462 samples was used for final analysis. Result - Higher consumer value means a greater chance that consumers will select that company's products over those of competitors. For competitive advantage purposes, companies use various consumer management strategies to bolster consumer value and corporate reputation with consumers. Conclusions - Brand assets are subject to ethical responsibility, which is a dimension of corporate social responsibility. Of note, one relevant finding about brand assets (similar to findings in previous research) is the existence of confusion about brand recognition and brand image as perceived by customers.

EXISTENCE RESULTS FOR POSITIVE SOLUTIONS OF NON-HOMOGENEOUS BVPS FOR SECOND ORDER DIFFERENCE EQUATIONS WITH ONE-DIMENSIONAL p-LAPLACIAN

  • Liu, Yu-Ji
    • 대한수학회지
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    • 제47권1호
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    • pp.135-163
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    • 2010
  • Motivated by [Science in China (Ser. A Mathematics) 36 (2006), no. 7, 721?732], this article deals with the following discrete type BVP $\LARGE\left\{{{\;{\Delta}[{\phi}({\Delta}x(n))]\;+\;f(n,\;x(n\;+\;1),{\Delta}x(n),{\Delta}x(n + 1))\;=\;0,\;n\;{\in}\;[0,N],}}\\{\;{x(0)-{\sum}^m_{i=1}{\alpha}_ix(n_i) = A,}}\\{\;{x(N+2)-\;{\sum}^m_{i=1}{\beta}_ix(n_i)\;=\;B.}}\right.$ The sufficient conditions to guarantee the existence of at least three positive solutions of the above multi-point boundary value problem are established by using a new fixed point theorem obtained in [5]. An example is presented to illustrate the main result. It is the purpose of this paper to show that the approach to get positive solutions of BVPs by using multifixed-point theorems can be extended to treat nonhomogeneous BVPs. The emphasis is put on the nonlinear term f involved with the first order delta operator ${\Delta}$x(n).

The Theory of the One-Dimensional Lattice Defects

  • Jhon, Mu-Shik;Kim, Shoon-Kyung
    • 대한화학회지
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    • 제15권4호
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    • pp.165-169
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    • 1971
  • A general method of calculating the frequency shift due to lattice defects is developed for a one dimensional lattice with an arbitrary number of lattice points. The method is based on the Fourier transform of the equation of motion. It is shown that the frequency spectrum is determined by the roots of 5${\times}$5 secular equation, the coefficients of which depend on defects in the mass and the force constant as well as the number of the lattice points. For the limiting case of infinite lattice, the dimension of the secular equation reduces to three and the result agrees with that of Montroll and Potts.

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케인방법을 이용한 구속 다물체계의 동역학 해석 (Dynamic analysis of constrained multibody systems using Kane's method)

  • 박정훈;유홍희;황요하;배대성
    • 대한기계학회논문집A
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    • 제21권12호
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    • pp.2156-2164
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    • 1997
  • A new formulation for the dynamic analysis of constrained multibody systems is presented in this paper. The formulation employs Kane's method along with the null space method. Kane's method reduces the dimension of equations of motion by using partial velocity matrix introduced in this study : it can improve the efficiency of the formulation. Three numerical examples are given to demonstrate the accuracy and efficiency of the formulation.

난류경계층의 헤어핀 다발구조에 대한 3차원 토폴로지 규명 (Identification of the three-dimensional topology of hairpin packet structures in turbulent boundary layers)

  • 권성훈;김경천
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.610-615
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    • 2003
  • This experiment has been carried out to find the structure of turbulent boundary layer with instantaneous velocity fields obtained in stream-wall-normal planes using a stereo-PIV (Particle Image Velocimetry) method. And it has been measured perpendicular plane and horizontal plane with hairpin vortex structure by Reynolds number change and made third dimension shape for section of horizontal plane through stereo-PIV. In the outer layer hairpin vortices occur in streamwise-aligned packets that propagate with small velocity dispersion. A streaky structure is composed of counter-rotating vortex. According as y+ increases, streaky structure's interval space decrease, and it shows that hairpin shape of prior research is vertified. The objective of the present research is to gain a better understanding of coherent structures in the outer of wall turbulence by experimentally examining coherent structures.

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Robust Diagnosis Algorithm for Identifying Broken Rotor Bar Faults in Induction Motors

  • Hwang, Don-Ha;Youn, Young-Woo;Sun, Jong-Ho;Kim, Yong-Hwa
    • Journal of Electrical Engineering and Technology
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    • 제9권1호
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    • pp.37-44
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    • 2014
  • This paper proposes a new diagnosis algorithm to detect broken rotor bars (BRBs) faults in induction motors. The proposed algorithm is composed of a frequency signal dimension order (FSDO) estimator and a fault decision module. The FSDO estimator finds a number of fault-related frequencies in the stator current signature. In the fault decision module, the fault diagnostic index from the FSDO estimator is used depending on the load conditions of the induction motors. Experimental results obtained in a 75 kW three-phase squirrel-cage induction motor show that the proposed diagnosis algorithm is capable of detecting BRB faults with an accuracy that is superior to a zoom multiple signal classification (ZMUSIC) and a zoom estimation of signal parameters via rotational invariance techniques (ZESPRIT).

Age Invariant Face Recognition Based on DCT Feature Extraction and Kernel Fisher Analysis

  • Boussaad, Leila;Benmohammed, Mohamed;Benzid, Redha
    • Journal of Information Processing Systems
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    • 제12권3호
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    • pp.392-409
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    • 2016
  • The aim of this paper is to examine the effectiveness of combining three popular tools used in pattern recognition, which are the Active Appearance Model (AAM), the two-dimensional discrete cosine transform (2D-DCT), and Kernel Fisher Analysis (KFA), for face recognition across age variations. For this purpose, we first used AAM to generate an AAM-based face representation; then, we applied 2D-DCT to get the descriptor of the image; and finally, we used a multiclass KFA for dimension reduction. Classification was made through a K-nearest neighbor classifier, based on Euclidean distance. Our experimental results on face images, which were obtained from the publicly available FG-NET face database, showed that the proposed descriptor worked satisfactorily for both face identification and verification across age progression.