• Title/Summary/Keyword: two-dimensional

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A Generic Craig Form for the Two-Dimensional Gaussian Q-Function

  • Park, Seung-Keun;Choi, U-Jin
    • ETRI Journal
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    • v.29 no.4
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    • pp.516-517
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    • 2007
  • In this letter we present a generic Craig form for the two-dimensional (2-D) Gaussian Q-function. The presented Craig form provides an alternative solution to the problems of computing probabilities involving a form of the 2-D Gaussian Q-function.

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Coherent Two-Dimensional Optical Spectroscopy

  • Cho, Min-Haeng
    • Bulletin of the Korean Chemical Society
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    • v.27 no.12
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    • pp.1940-1960
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    • 2006
  • Theoretical descriptions of two-dimensional (2D) vibrational and electronic spectroscopy are presented. By using a coupled multi-chromophore model, some examples of 2D spectroscopic studies of peptide solution structure determination and excitation transfer process in electronically coupled multi-chromophore system are discussed. A few remarks on perspectives of this research area are given.

COMPARISON OF TWO- AND THREE-DIMENSIONAL SUPERSONIC TURBULENT FLOWS OVER A SINGLE CAVITY (단일 공동주위의 2차원과 3차원 초음속 유동 비교)

  • Woo C.H.;Kim J.S.
    • 한국전산유체공학회:학술대회논문집
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    • 2005.10a
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    • pp.235-238
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    • 2005
  • The unsteady supersonic flow over two- and three-Dimensional cavities has been analyzed by the integration of unsteady Reynolds-Averaged Navier-Stokes(RANS) with the k - w turbulence model. The unsteady flow is characterized by the periodicity due to the mutual relation between the shear layer and the internal flow in cavities. Numerical method is upwind TVD scheme based on the flux vector split with the Van Leer limiters, and time accuracy is used explicit 4th stage Runge-Kutta scheme. Cavity flows are Comparison of two- and three-dimensional. The cavity has a L/D ratio of 3 for two-dimensional case. and same L/D and W/D ratio is 1 for three-dimensional case. The Mach and Reynolds numbers are held constant at 1.5 and 450000 respectively. For the three-dimensional case, the flow field is observed to oscillate in the 'shear layer mode' with a feedback mechanism that follow Rossiter's formula. On the other hand, the self-sustained oscillating flow transitions to a 'wake mode' for the two-dimensional simulation, with more violent fluctuations inside the cavity.

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Modified Lysmer's analog model for two dimensional mat settlements under vertically uniform load

  • Chang, Der-Wen;Hung, Ming-He;Jeong, Sang-Seom
    • Geomechanics and Engineering
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    • v.25 no.3
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    • pp.221-231
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    • 2021
  • A two dimensional model of linearly elastic soil spring used for the settlement analysis of the flexible mat foundation is suggested in this study. The spring constants of the soils underneath the foundation were modeled assuming uniformly vertical load applied onto the foundation. The soil spring constants were back calculated using the three-dimensional finite element analysis with Midas GTS NX program. Variation of the soil spring constants was modeled as a two-dimensional polynomial function in terms of the normalized spatial distances between the center of foundation and the analytical points. The Lysmer's analog spring for soils underneath the rigid foundation was adopted and calibrated for the flexible foundation. For validations, the newly proposed soil spring model was incorporated into a two dimensional finite difference analysis for a square mat foundation at the surface of an elastic half-space consisting of soft clays. Comparative study was made for elastic soils where the shear wave velocity is 120~180 m/s and the Poisson's ratio varies at 0.3~0.5. The resulting foundation settlements from the two dimensional finite difference analysis with the proposed soil springs were found in good agreement with those obtained directly from three dimensional finite element analyses. Details of the applications and limitations of the modified Lysmer's analog springs were discussed in this study.

An Improved Exact Algorithm for the Unconstrained Two-Dimensional Cutting Problem (개수 제한이 없는 2차원 절단문제를 위한 향상된 최적해법)

  • Gee, Young-Gun;Kang, Maing-Kyu
    • Journal of Korean Institute of Industrial Engineers
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    • v.27 no.4
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    • pp.424-431
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    • 2001
  • This paper is concerned with the unconstrained two-dimensional cutting problem of cutting small rectangles (products), each of which has its own profit and size, from a large rectangle (material) to maximize the profit-sum of products. Since this problem is used as a sub-problem to generate a cutting pattern in the algorithms for the two-dimensional cutting stock problem, most of researches for the two-dimensional cutting stock problem have been concentrated on solving this sub-problem more efficiently. This paper improves Hifi and Zissimopoulos's recursive algorithm, which is known as the most efficient exact algorithm, by applying newly proposed upper bound and searching strategy. The experimental results show that the proposed algorithm has been improved significantly in the computational amount of time as compared with the Hifi and Zissimopulos's algorithm.

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2D Grid Map Compensation using an ICP Algorithm (ICP 알고리즘을 이용한 2차원 격자지도 보정)

  • Lee, Dong-Ju;Hwang, Yu-Seop;Yun, Yeol-Min;Lee, Jang-Myung
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.11
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    • pp.1170-1174
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    • 2014
  • This paper suggests using the ICP (Iterative Closet Point) algorithm to compensate a two-dimensional map. ICP algorithm is a typical algorithm method using matching distance data. When building a two-dimensional map, using data through the value of a laser scanner, it occurred warping and distortion of a two-dimensional map because of the difference of distance from the value of the sensor. It uses the ICP algorithm in order to reduce any error of line. It validated the proposed method through experiment involving matching a two-dimensional map based reference data and measured the two-dimensional map.

인공장기

  • 민병구
    • Journal of Biomedical Engineering Research
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    • v.10 no.2
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    • pp.112-113
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    • 1989
  • Two-Dimensional modelling of the Cochlear biomechanics is presented in this paper. The Laplace partial differential equation which represents the fluid mechanics of the Cochlea has been transformed into two-dimensional electrical transmission line. The procedure of this transformation is explained in detail. The comparison between one and two dimensional models is also presented. This electrical modelling of the basilar membrane (BM) is clearly useful for the next approach to the further. Development of active elements which are essential in the producing of the sharp tuning of the BM. This paper shows that two-dimension model is qualitatively better than one-dimensional model both in amplitude and phase responses of the BM displacement. The present model is only for frequency response. However because the model is electrical, the two-dimensional transmission line model can be extended to time response without any difficult.

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Suppression of Spin Dephasing in a Two-Dimensional Electron Gas with a Quantum Point Contact

  • Jeong, Jae-Seung;Lee, Hyun-Woo
    • Journal of Magnetics
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    • v.15 no.1
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    • pp.7-11
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    • 2010
  • Spin-orbit coupling (SOC) is a source of strong spin dephasing in two- and three-dimensional semiconducting systems. We report that spin dephasing in a two-dimensional electron gas can be suppressed by introducing a quantum point contact. Surprisingly, this suppression was not limited to the vicinity of the contact but extended to the entire two-dimensional electron gas. This facilitates the electrical control of the spin degree of freedom in a two-dimensional electron gas through spin-orbit coupling.

FLOW CHARACTERISTICS OF A TWO-DIMENSIONAL NEUTRALLY BUOYANT JET IN A MODEL SETTLING TANK

  • Kim, Young-han;Seo, Il-Won;Ahn, Jung-kyu
    • Water Engineering Research
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    • v.2 no.1
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    • pp.21-31
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    • 2001
  • In this study, laboratory experiments were performed to investigate the flow characteristics of a two-dimensional neutrally buoyant jet in the inlet region of a rectangular laboratory settling tank. Velocity measurements were made with a three-component ADV. Two types of baffles were installed in front of two-dimensional slot; a one-sided and a two-sided baffle. The flow fields from a plane jet impinging on these two types of baffles and a plane jet without a baffle showed quite different characteristics. To concentrate on investigating these flow characteristics, the effects of density currents due to temperature difference or the presence of sediments were not studied. Results of the experiments reveal that the use of the two-sided baffle results in the shortest inlet region. Also shown is that, in addition to the types of baffles, the Froude number turns out to be an important factor in the extent of the inlet region.

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