• 제목/요약/키워드: data interpolation

검색결과 1,020건 처리시간 0.022초

최적해저지형정보 추출을 위한 보간법 선정 (Selecting of Interpolation for Extraction of Optimal Submarine Topographic Information.)

  • 이종출;김희규;김남식;김성호
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 춘계학술발표회논문집
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    • pp.571-576
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    • 2004
  • In this study, we selected the most effective interpolation method using both the data of sounding the depth of submarine topography and volume-production computer program. After processing the data by volume-production program, and then we selected the most effective interpolation method which nearest actual value of dredged soil quantity. Thus, these interpolation could be used for describing the optimal submarine topography.

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NURBS Surface Global Interpolation에 대한 한 방법 (A New Method of the Global Interpolation in NURBS Surface)

  • 정형배;나승수;박종환
    • 한국CDE학회논문집
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    • 제2권4호
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    • pp.237-243
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    • 1997
  • A new method is introduced for the interpolation in NURBS Surface. This method uses the basis functions to assign the parameter values to the arbitrary set of geometric data and uses the iteration method to compute the control net. The advantages of this method are the feasible transformation of the data set to the matrix form and the effective surface generation as a result, especially to the design engineer.

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INFLUNCE OF THE TOPOGRAPHIC INTERPOLATION METHODS ON HIGH-RESOLUTION WIND FIELD SIMULATION WITH SRTM ELEVATION DATA OVER THE COASTAL AREA

  • Kim, Yoo-Keun;Lo, So-Young;Jeong, Ju-Hee
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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    • pp.297-300
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    • 2008
  • High-resolution mesoscale meteorological modeling requires more accurate and higher resolution digital elevation model (DEM) data. Shuttle Radar Topographic Mission (SRTM) has created 90 m DEM for entire globe and that is freely available for meteorological modeling and environmental applications. In this research, the effects of the topographic interpolation methods on high-resolution wind field simulation in the coastal regions were quantitatively analyzed using Weather Research and Forecasting (WRF) model with SRTM data. Sensitivity experiments with three different interpolation schemes (four-point bilinear, sixteen-point overlapping parabolic and nearest neighbor interpolation methods) were preformed using SRTM. In WRF modeling with sixteen-point overlapping parabolic interpolation, the coastal line and some small islands show more clearly than other cases. The maximum height of inland is around 140 meters higher, while the minimum of sea height is about 80 meter lower. As it concerns the results of each scheme it seems that the sixteen-point overlapping parabolic scheme indicates the well agreement with observed surface wind data. Consequently, topographic changes due to interpolation methods can lead to the significant influence on mesoscale wind field simulation of WRF modeling.

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A Generalized Image Interpolation-based Reversible Data Hiding Scheme with High Embedding Capacity and Image Quality

  • Tsai, Yuan-Yu;Chen, Jian-Ting;Kuo, Yin-Chi;Chan, Chi-Shiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권9호
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    • pp.3286-3301
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    • 2014
  • Jung and Yoo proposed the first image interpolation-based reversible data hiding algorithm. Although their algorithm achieved superior interpolation results, the embedding capacity was insufficient. Lee and Huang proposed an improved algorithm to enhance the embedding capacity and the interpolation results. However, these algorithms present limitations to magnify the original image to any resolution and pixels in the boundary region of the magnified image are poorly manipulated. Furthermore, the capacity and the image quality can be improved further. This study modifies the pixel mapping scheme and adopts a bilinear interpolation to solve boundary artifacts. The modified reference pixel determination and an optimal pixel adjustment process can effectively enhance the embedding capacity and the image quality. The experimental results show our proposed algorithm achieves a higher embedding capacity under acceptable visual distortions, and can be applied to a magnified image at any resolution. Our proposed technique is feasible in reversible data hiding.

PMSM 토크제어를 위한 보간오차 보상방법 (Interpolation Error Compensation Method for PMSM Torque Control)

  • 이정효
    • 전기학회논문지
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    • 제67권3호
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    • pp.391-397
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    • 2018
  • This paper proposes a interpolation error compensation method for PMSM torque control. In PMSM torque control, two dimensions look-up table(2D-LUT) is used for current reference generation due to its stable and robust torque control performance. However, the stored data in 2D-LUT is discreet, it is impossible to store all over the operation range. To reduce the reference generation error in this region, the 2D-Interpolation method is conventionally used, however, this method still remains the error affected by the number of stored data. Besides, in the case stored by fixed unit, this error is increased in field weakening region because of the small number of stored data. In this paper, analyzing the cause of this interpolation error, and compensating the method to reduce this error. Proposed method is verified by the simulation and experiment.

마늘 재배적지분석을 위한 기온자료 공간보간기법 비교 (Comparison between Spatial Interpolation Methods of Temperature Data for Garlic Cultivation)

  • 김용완;홍석영;장민원
    • 한국농공학회논문집
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    • 제53권5호
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    • pp.1-7
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    • 2011
  • The objective of this study is to decide a spatial interpolation method on temperature data for the suitability analysis of garlic cultivation. In Korea, garlic is the second most cultivated condiment vegetable after red pepper. Nowadays warm-temperate garlic faces potential shift of its arable area according to warmer temperature in the Korean Peninsula, and the change can be drawn with the precise temperature map derived from interpolation on point-measured data. To find the preferable interpolation method in cases of germination and vegetative period of the garlic, different approaches were tested as follows: Inverse Distance Weighted (IDW), Spline, Ordinary Kriging (OK), and Universal Kriging (UK). As a result, IDW and UK show the lowest root mean square errors as for the germination and vegetative seasons, respectively. However, statistically significant difference was not revealed among the applied methods regarding the germinating period. Eventually this will contribute to mapping the suitable lands for the cultivation of warm-temperate garlic reasonably.

Weight Control and Knot Placement for Rational B-spline Curve Interpolation

  • Kim, Tae-Wan;Lee, Kunwoo
    • Journal of Mechanical Science and Technology
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    • 제15권2호
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    • pp.192-198
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    • 2001
  • We consider an interpolation problem with nonuniform rational B-spline curves given ordered data points. The existing approaches assume that weight for each point is available. But, it is not the case in practical applications. Schneider suggested a method which interpolates data points by automatically determining the weight of each control point. However, a drawback of Schneiders approach is that there is no guarantee of avoiding undesired poles; avoiding negative weights. Based on a quadratic programming technique, we use the weights of the control points for interpolating additional data. The weights are restricted to appropriate intervals; this guarantees the regularity of the interpolating curve. In a addition, a knot placement is proposed for pleasing interpolation. In comparison with integral B-spline interpolation, the proposed scheme leads to B-spline curves with fewer control points.

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NURBS Surface Global Interpolation에 대한 한 방법: II (A New Method of the Global Interpolation in NURBS Surface: II)

  • 정형배
    • 한국CDE학회논문집
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    • 제3권4호
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    • pp.243-250
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    • 1998
  • In parametric surface interpolation, the choice of the parameter values to the set of scattered points makes a great deal of difference in the resulting surface. A new method is developed and tested for the parametrization in NURBS surface global interpolation. This method uses the parameter value at the maximal value of relevant rational basis function, to assign the parameter values to the arbitrary set of design data. This method gives us several important advantages in geometric modeling, the freedom of the selection of knot values, the feasible transformation of the data set to the matrix, the possibility of affinite transformation between the design data and generated surface, etc.

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새로운 투영 데이터 수집방법을 이용한 불완전한 데이터로부터 영상 재구성 (Image Reconstruction from Incomplete Data Using a New Data Acquisition Method)

  • 정병문;박길흠;하영호
    • 대한전자공학회논문지
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    • 제25권12호
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    • pp.1559-1565
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    • 1988
  • In computed tomography, the errors asociated with interpolation in the reconstruction process degrade the reconstructed image and may cause divergence unless a large number of rays is used. A new data acquisition scheme without interpolation is developed in this paper. Samples (projection data ) are taken in phase with samples of the Cartesian grid to eliminated errors associated with interpolation process.

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Interpolation을 이용한 3-CUP Anemometer의 성능 개선에 관한 연구 (The Study of Performance Improvement of the 3-Cup Anemometer using Interpolation Methods)

  • 이성신;정택식;구법모
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2001년도 춘계종합학술대회
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    • pp.672-675
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    • 2001
  • 본 논문에서 Interpolation Methods를 이용하여 보다 정화한 풍속을 계산하는 방법과 보다 정확한 풍향을 계산하기 위하여 Interpolation Polynomial을 찾는 방법을 제안하였고, 이렇게 제안된 방법을 이용하여 3-Cup Anemometer의 성능을 개선하였다. 우리는 풍향, 풍속의 관측을 위해 기구부는 3-cup Type Anemometer로, 전자부는 Photo Sensor를 이용하여 구현하였다. 정확한 풍속과 풍향의 측정을 위해서는 시스템의 메모리 한계 및 성능을 고려한 시스템 설계와 8비트 Gray Code Film으로 256(= 2$^{8}$ )개의 각도 Data로 360$^{\circ}$를 표현하는 방법이다.

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