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The Effective Method for Changing the Resolution of the Grid Environment Data (다수/다차원 격자형데이터를 이용한 해상도 변환의 효율적 방안 연구)

  • Kim, Chang-Jin;Oh, Gwang-Beak;Na, Young-Nam
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.2
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    • pp.169-174
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    • 2013
  • In counterfire warfare, it is important to detect and attack enemy targets faster than the enemy using sensing The grided environmental data is usually provided by the numerical simulation coupled with a data assimilation technique and various inter- or extrapolation algorithms, both of which are based on the observation spanning from simple equipments to satellites. In order to employ the gridded environmental data in the M&S system frequently cutting area and changing its resolution, interpolation algorithms such as linear, cubic spline, IDW, and Kriging methods are necessary to apply. These methods, however, require much time in the M&S system. This paper introduces a technic to reduce time to change the resolution of data. using the binary search method, which finds a point to interpolate quickly and interpolate data in the vicinity of. We also show the efficiency of proposed methods by way of measuring the respective elapsed times.

DEVELOPMENT OF AN UNSTRUCTURED OVERSET MESH METHOD FOR 2-D UNSTEADY VISCOUS FLOW ANALYSIS (이차원 비정상 점성 유동 해석을 위한 비정렬 중첩격자기법 개발)

  • Jung M. S.;Kwon O. J.
    • 한국전산유체공학회:학술대회논문집
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    • 2005.10a
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    • pp.135-139
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    • 2005
  • An unstructured overset mesh method has been developed for the simulation of unsteady viscous flow fields around multiple bodies in relative motion. For this purpose, a robust and fast search technique is proposed for both triangle and high-aspect quadrilateral cell elements. The interpolation boundary is defined for data communication between grid systems and an interpolation method is suggested for viscous and inviscid cell elements. This method has been applied to calculate the flow fields around 2-D airfoil including relative motion. Validation were made by comparing the predicted results with those of experiments or other researcher's numerical results. It was demonstrated that the present method is efficient and robust for the prediction of unsteady time-accurate flow fields involving multiple bodies in relative motion.

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DEVELOPMENT OF AN UNSTRUCTURED OVERSET MESH METHOD FOR 2-D UNSTEADY VISCOUS FLOW SIMULATION WITH RELATIVE MOTION (상대운동이 있는 이차원 비정상 점성 유동 해석을 위한 비정렬 중첩격자기법 개발)

  • Jung Mun-Seung;Kwon Oh-Joon
    • Journal of computational fluids engineering
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    • v.11 no.2 s.33
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    • pp.1-7
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    • 2006
  • An unstructured overset mesh method has been developed for the simulation of unsteady viscous flow fields around multiple bodies in relative motion. For this purpose, a robust and fast search technique is proposed for both triangle and high-aspect ratio quadrilateral cell elements. The interpolation boundary is defined for data communication between grid systems and an interpolation method is suggested for viscous and inviscid cell elements. This method has been applied to calculate the flow fields around 2-D airfoils involving relative motion. Validations were made by comparing the predicted results with those of experiments or other numerical results. It was demonstrated that the present method is efficient and robust for the prediction of unsteady time-accurate flow fields involving multiple bodies in relative motion.

Investigation of Strain Measurements using Digital Image Correlation with a Finite Element Method

  • Zhao, Jian;Zhao, Dong
    • Journal of the Optical Society of Korea
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    • v.17 no.5
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    • pp.399-404
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    • 2013
  • This article proposes a digital image correlation (DIC) strain measurement method based on a finite element (FE) algorithm. A two-step digital image correlation is presented. In the first step, the gradient-based subpixels technique is used to search the displacements of a region of interest of the specimen, and then the strain fields are obtained by utilizing the finite element method in the second step. Both simulation and experiment processing, including tensile strain deformation, show that the proposed method can achieve nearly the same accuracy as the cubic spline interpolation method in most cases and higher accuracy in some cases, such as the simulations of uniaxial tension with and without noise. The results show that it also has a good noise-robustness. Finally, this method is used in the uniaxial tensile testing for Dahurian Larch wood specimens with or without a hole, and the obtained strain values are close to the results which were obtained from the strain gauge and the cubic spline interpolation method.

A Study on Fast Maximum Efficiency Control of Stator-Flux-oriented Induction Motor Drives

  • Shin, Myoung-Ho
    • Journal of Electrical Engineering and Technology
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    • v.6 no.5
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    • pp.626-633
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    • 2011
  • This paper presents a novel maximum efficiency control scheme for convergence improvement in stator-flux-oriented induction motor drives. Three input powers are calculated at three different flux levels, respectively. A quadratic curve is obtained using the quadratic interpolation method using the three points. The flux level at the lowest point of the interpolated curve is calculated, which is not the real minimum input power of the motor, but an estimated one. Hence, the quadratic interpolations are repeated with three new points chosen using the selection method for new points for refitting until the convergence criteria are satisfied. The proposed method is verified by simulation results.

A Center Biased Cross-Diamond Search Algorithm for Fast Fractional-pel Motion Estimation (고속 부화소 움직임 추정을 위한 중심 지향적 십자 다이아몬드 탐색 알고리즘)

  • Jo, Seong-Hyeon;Lee, Jong-Hwa
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.2
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    • pp.78-84
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    • 2009
  • In general video coding systems, motion estimation (ME) is regarded as a vital component in a video coder as it consumes a large amount of computation resources. Fractional pixel motion estimation can improve the video compression rate at the cost of higher computational complexity. It is based on the experimental results that the sum of absolute differences (SAD) shows parabolic shape and thus can be approximated by using interpolation technique. In this paper, we propose a fast fractional pixel search algorithm by combining SASR (Simplified Adaptive Search Range) and the CBCDS (Center Biased Cross-Diamond Search) pattern with the predicted motion vector. Compare with the fractional pel full search and the CBFPS, the proposed CBCDS algorithms can reduce fractional pel search points up to 81.4%, respectively with the PSNR lost about 0.05dB.

A Study on the Interpolation Characteristics of the Scattered Geographic Data according to the Gridding methods (격자화 기법에 따른 이산지형정보의 보간특성 연구)

  • Lee, Yong-Chang
    • Journal of Korean Society for Geospatial Information Science
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    • v.4 no.2 s.8
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    • pp.173-180
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    • 1996
  • In a grid based data transformation, the different gridding methods provide different interpretations of scattered data because each method calculate grid node values using a different weighted mathematical algorithms. Therefore, it is necessary to review the interpolated characteristics of some gridding methods according to search distance, search area and search options before determing the best method with a data set. For this, in this paper, six different gridding methods with the same search conditions are applied to a scattered data obtained from sterro-plotter. The interpolated characteristics of the scattered geographic data considered through comparison of coincidence between the data point and the grid node being interpolated. And also, shows the real application of gridding methods through calculating volumes and creating cross sections.

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Improvement OCR Algorithm for Efficient Book Catalog RetrievalTechnology (효과적인 도서목록 검색을 위한 개선된 OCR알고리즘에 관한 연구)

  • HeWen, HeWen;Baek, Young-Hyun;Moon, Sung-Ryong
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.47 no.1
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    • pp.152-159
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    • 2010
  • Existing character recognition algorithm recognize characters in simple conditional. It has the disadvantage that recognition rates often drop drastically when input document image has low quality, rotated text, various font or size text because of external noise or data loss. In this paper, proposes the optical character recognition algorithm which using bicubic interpolation method for the catalog retrieval when the input image has rotated text, blurred, various font and size. In this paper, applied optical character recognition algorithm consist of detection and recognition part. Detection part applied roberts and hausdorff distance algorithm for correct detection the catalog of book. Recognition part applied bicubic interpolation to interpolate data loss due to low quality, various font and size text. By the next time, applied rotation for the bicubic interpolation result image to slant proofreading. Experimental results show that proposal method can effectively improve recognition rate 6% and search-time 1.077s process result.

Colour Interpolation of Tongue Image in Digital Tongue Image System Blocking Out External Light (디지털 설진 시스템의 색상 보정)

  • Kim, Ji-Hye;Nam, Dong-Hyun
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.16 no.1
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    • pp.9-18
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    • 2012
  • Objectives The aim of this study is to propose an optimized tongue colour interpolation method to achieve accurate tongue image rendering. Methods We selected 60 colour chips in the chips of DIC color guide selector, and then divided randomly the colour chips into two groups. The colour chips of a group (Gr I) were used for finding the optimized colour correction factor of error and those of the other group (Gr II) were used for verifying the correction factor. We measured colour value of the Gr I colour chips with spectrophotometer, and took the colour chips image with a digital tongue image system (DTIS). We adjusted colour correction factor of error to equal the chip colour from each method. Through that process, we obtained the optimized colour correction factor. To verify the correction factor, we measured colour value of the Gr II colour chips with a spectrophotometer, and took the colour chips image with the DTIS in the two types of colour interpolation mode (auto white balance mode and optimized colour correction factor mode). And then we calculated the CIE-$L^*ab$ colour difference (${\Delta}E$) between colour values measured with the spectrophotometer and those from images taken with the DTIS. Results In auto white balance mode, The mean ${\Delta}E$ between colour values measured with the spectrophotometer and those from images taken with the DTIS was 13.95. On the other hand, in optimized colour correction factor mode, The mean ${\Delta}E$ was 9.55. The correction rate was over 30%. Conclusions In case of interpolating colour of images taken with the DTIS, we suggest that procedure to search the optimized colour correction factor of error should be done first.

A Design of 4×4 Block Parallel Interpolation Motion Compensation Architecture for 4K UHD H.264/AVC Decoder (4K UHD급 H.264/AVC 복호화기를 위한 4×4 블록 병렬 보간 움직임보상기 아키텍처 설계)

  • Lee, Kyung-Ho;Kong, Jin-Hyeung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.5
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    • pp.102-111
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    • 2013
  • In this paper, we proposed a $4{\times}4$ block parallel architecture of interpolation for high-performance H.264/AVC Motion Compensation in 4K UHD($3840{\times}2160$) video real time processing. To improve throughput, we design $4{\times}4$ block parallel interpolation. For supplying the $9{\times}9$ reference data for interpolation, we design 2D cache buffer which consists of the $9{\times}9$ memory arrays. We minimize redundant storage of the reference pixel by applying the Search Area Stripe Reuse scheme(SASR), and implement high-speed plane interpolator with 3-stage pipeline(Horizontal Vertical 1/2 interpolation, Diagonal 1/2 interpolation, 1/4 interpolation). The proposed architecture was simulated in 0.13um standard cell library. The maximum operation frequency is 150MHz. The gate count is 161Kgates. The proposed H.264/AVC Motion Compensation can support 4K UHD at 72 frames per second by running at 150MHz.