• 제목/요약/키워드: ADI algorithm

검색결과 31건 처리시간 0.023초

수평 및 수직 윤곽선을 개선한 적응 주사선 보간 알고리즘에 관한 연구 (A study of the adaptive de-interlacing up-conversions for enhancement horizontal and vertical edges)

  • 배준석;박노경;문대철
    • 전자공학회논문지S
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    • 제35S권2호
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    • pp.114-125
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    • 1998
  • In this study, for the first time, we propose the ADI(Adaptive De-Interlacing) algorithm, which improves visually and subjectively, horizontal and vertical edges on the image processed by the ELA (Edge Based Line Average) method. The proposed ADI algorithm enlargesthe window size to 5*3 in order to utilize the feature of the continuity of edges, and the adaptive interpolator is employed to decide adaptiely horizontal, diagonal, and vertical edges. Based on the results of the compter simulation, it is confimed that the new ADI algorithm improve the PSNR by 0.5dB in the Lena image with 512*512 size and by 0.4dB in the sequence image of a salesman, respectively. For the horizontal and vertial edges on the still and salesman sequence images, the proposed ADI algorithm has better visulal improvement than the conventional ELA algorithm.

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음해법을 이용한 천수방정식의 수치해석 (Numerical Analysis of Shallow Water Equation with Fully Implicit Method)

  • 강주환;박상현;이길성
    • 대한토목학회논문집
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    • 제13권3호
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    • pp.119-127
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    • 1993
  • 근래 천수방정식과 같은 2차원 수치해석에서 가장 널리 쓰이는 방법 중의 하나로 ADI 방법을 들 수 있다. 그러나 서해안과 같이 수심의 변화가 심하며 특히 해저협곡이 곳곳에 발달된 해역에서 조석에 관한 문제해결시 ADI 방법을 사용하면 소위 ADI 효과가 크게 우려된다. 이를 극복하기 위하여 완전 음해법으로 차분되고 CGS(conjugate gradient squared) 방법으로 해를 구하는 알고리즘을 개발하였다. 조간대 모의가 포함된 본 모형용 새만금 수역에 적용한 결과 지형의 복잡성에도 불구하고 유속장과 조간대 형성에 관한 수치적 모의가 만족스러운 결과를 보였다.

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Compact 2D ADI-FDTD를 이용한 도파관 구조의 분산특성 연구 (Dispersion Analysis of the Waveguide Structures by Using the Compact 2D ADI-FDTD)

  • 어수지;천정남;박현식;김형동
    • 대한전자공학회논문지TC
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    • 제39권10호
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    • pp.38-45
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    • 2002
  • 본 논문에서는 기존의 Compact 2D FDTD(Finite-Difference Time-Domain)에 대한 고속 알고리즘으로써 시간간격 △t가 안정조건(Stability Condition)에 의해 제한받지 않는 Compact 2D ADI(Alternating Direction Implicit)-FDTD 차분식을 제안하였다. 또한 구현된 알고리즘의 정확성 및 효율성을 검증하기 위하여 내부가 공기로 채워져 있는 구형(Rectangular) 도파관과 차폐된 전송선로를 해석하였다. 본 논문의 결과는 기존의 Compact 2D FDTD의 결과 및 해석적인 해와 매우 잘 일치하며, 계산 소요시간도 기존의 Compact 2D FDTD에 비해 상당히 절약되었음을 확인하였다. 제안된 알고리즘은 도파관 구조의 분산 특성 연구에 있어 효율적인 고속화 기술로서 의미가 있다고 할 수 있다.

GPR 시스템 시뮬레이션을 위한 3차원 ADI-FDTD 기법의 적용 (Application of 3D ADI-FDTD Method for GPR System Simulation)

  • 전원석;여운식;윤승현;김형동
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 하계종합학술대회 논문집(1)
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    • pp.131-134
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    • 2004
  • This paper has been studied a ADI-FDTD(Alternating Direction Implicit Finite Difference Time Domain ) algorithm using an alternating Direction time-stepping scheme for GPR( Ground-Penetrating Radar ) system simulation. We did the numerical formulations for three-dimensional ADI-FDTD algorithm and PML(Perfect Matched Layer), and made an simple experiment on a arbitrary cube with programed algorithms. And then we compared its computed results with those of conventional FDTD.

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Is it Possible to Predict the ADI of Pesticides using the QSAR Approach?

  • Kim, Jae Hyoun
    • 한국환경보건학회지
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    • 제38권6호
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    • pp.550-560
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    • 2012
  • Objectives: QSAR methodology was applied to explain two different sets of acceptable daily intake (ADI) data of 74 pesticides proposed by both the USEPA and WHO in terms of setting guidelines for food and drinking water. Methods: A subset of calculated descriptors was selected from Dragon$^{(R)}$ software. QSARs were then developed utilizing a statistical technique, genetic algorithm-multiple linear regression (GA-MLR). The differences in each specific model in the prediction of the ADI of the pesticides were discussed. Results: The stepwise multiple linear regression analysis resulted in a statistically significant QSAR model with five descriptors. Resultant QSAR models were robust, showing good utility across multiple classes of pesticide compounds. The applicability domain was also defined. The proposed models were robust and satisfactory. Conclusions: The QSAR model could be a feasible and effective tool for predicting ADI and for the comparison of logADIEPA to logADIWHO. The statistical results agree with the fact that USEPA focuses on more subtle endpoints than does WHO.

컴퓨터 비젼을 이용한 컨테이너 자세 측정 (The Container Pose Measurement Using Computer Vision)

  • 주기세
    • 한국정보통신학회논문지
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    • 제8권3호
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    • pp.702-707
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    • 2004
  • 본 논문은 CCD 카메라와 거리 센서를 사용하여 컨테이너의 자세 측정에 관하여 연구하였다. 특히 특징점을 추출하고 영상의 잡음을 줄이는 방법에 대하여 중점적으로 기술하였다. 가우시안 및 랜덤 노이즈를 제거하기 위하여 Euler-Lagrange 방정식을 소개하였으며 PDE(Partial Differential Equation)를 기초로 한 Euler-Lagrange 방정식을 풀기 위하여 ADI(Alternating Direction Implicit)방법을 적용하였다. 그리고 스프레더와 컨테이너의 특징점을 추출하기 위해서 기존의 황금 분할법과 이분 분할법을 이용한 방법은 지역적 최대 및 최소 값의 경우 정확한 해를 구할 수 없어서 k차 곡률 알고리즘을 이용하였다. 제안된 알고리즘은 영상의 전처리과정에서 잡음제거에 효과적이며 카메라와 거리센서를 이용한 제안 시스템은 기존시스템의 구조적 변경 없이 사용가능하기 때문에 비용이 저렴한 장점이 있다.

ADI 보간 알고리듬을 적용한 Color Space Converter 칩 설계에 관한 연구 (A study of the color De-interlacing ASIC Chip design adopted the improved interpolation Algorithm for improving the picture quality using color space converter.)

  • 이치우;박노경;진현준;박상봉
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(4)
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    • pp.199-202
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    • 2001
  • A current TV-OUT format is quite different from that of HDTY or PC monitor in encoding techniques. In other words, a conventional analog TV uses interlaced display while HDTV or PC monitor uses Non-interlaced / Progressive-scanned display. In order to encode image signals coming from devices that takes interlaced display format for progressive scanned display, a hardware logic in which scanning and interpolation algorithms are implemented is necessary. The ELA (Edge-Based Line Average) algorithm have been widely used because it provided good characteristics. In this study, the ADI(Adaptive De-interlacing Interpolation) algorithm using to improve the algorithm which shows low quality in vertical edge detections and low efficiency of horizontal edge lines. With the De-interlacing ASIC chip that converts the interlaced Digital YUV to De-interlaced Digital RGB is designed. The VHDL is used for chip design.

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수평 및 수직 윤곽선을 개선한 ADI(Adaptive De-interlacing) 보간 알고리즘의 ASIC 설계 (The ASIC Design of the Adaptive De-interlacing Algorithm with Improved Horizontal and Vertical Edges)

  • 한병혁;박노경;배준석;박상봉
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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    • pp.139-142
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    • 2000
  • In this paper, the ADI (Adaptive De-interlacing) algorithm is proposed, which improves visually and subjectively horizontal and vertical edges of the image processed by the ELA(Edge Line-based Average) method. This paper also proposes a VLSI architecture for the proposed algorithm and designed the architecture through the full custom CMOS layout process. The proposed algorithm is verified using C and Matlab and implemented using 0.6$\mu\textrm{m}$ 2-poly 3-metal CMOS standard libraries. For the circuit and logic simulation, Cadence tool is used.

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An Alternating Implicit Block Overlapped FDTD (AIBO-FDTD) Method and Its Parallel Implementation

  • Pongpaibool, Pornanong;Kamo, Atsushi;Watanabe, Takayuki;Asai, Hideki
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -1
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    • pp.137-140
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    • 2002
  • In this paper, a new algorithm for two-dimensional (2-D) finite-difference time-domain (FDTD) method is presented. By this new method, the maximum time step size can be increased over the Courant-Friedrich-Levy (CFL) condition restraint. This new algorithm is adapted from an Alternating-Direction Implicit FDTD (ADI-FDTD) method. However, unlike the ADI-FDTD algorithm. the alternation is performed with respect to the blocks of fields rather than with respect to each respective coordinate direction. Moreover. this method can be efficiently simulated with parallel computation. and it is more efficient than the conventional FDTD method in terms of CPU time. Numerical formulations are shown and simulation results are presented to demonstrate the effectiveness and efficiency of our proposed method.

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3차원 압축성 유동 해석을 위한 효율적인 다중 격자 DADI 기법 (An Efficient Multigrid Diagonalized ADI Method for 3-Dimensional Compressible Flow Analysis)

  • 박수형;성춘호;권장혁
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 1998년도 춘계 학술대회논문집
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    • pp.29-34
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    • 1998
  • An efficient 3-dimensional compressible solver is developed using the second-order upwind TVD scheme and the multigrid diagonalized ADI method. The multigrid method is improved so that the present DADI algorithm obtains better convergence rates. Results are computed on Cray C90 computer for transonic unsaperated flows past ONERA-M6 wing to demonstrate the accuracy and efficiency. The results show good agreement with experimetal data. A reduction of four orders of residual for 3-dimensional transonic flow is obtained about 99 seconds.

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