• 제목/요약/키워드: Interpolation accuracy

검색결과 455건 처리시간 0.03초

Comparisons of Various DEM Interpolation Techniques

  • Kim, Tae-Jung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.163-168
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    • 1998
  • Extracting a Digital Elevation Model (DEM) from spaceborne imagery is important for cartographic applications of remote sensing data. The procedure for such DEM generation can be divided into stereo matching, sensor modelling and DEM interpolation. Among these, DEM interpolation contributes significantly to the completeness and accuracy of a DEM and, yet, this technique is often considered "trivial". However, na\ulcornere DEM interpolation may result in a less accurate and sometimes meaningless DEM. This paper reports the performance analysis of various DEM interpolation techniques. Using a manually derived DEM as reference, a number of sample points were created randomly. Different interpolation techniques were applied to the sample points to generate DEMs. The performance of interpolation was assessed by the accuracy of such DEMs. The results showed that kriging gave the best results at all times whereas nearest neighborhood interpolation provided a fast solution with moderate accuracy when sample points were large enough.

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수지표고지형의 정확도 향상을 위한 지형의 분류와 보간법의 상용에 관한 연구 (A Study on the Application of Interpolation and Terrain Classification for Accuracy Improvement of Digital Elevation Model)

  • 문두열
    • 한국해양공학회지
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    • 제8권2호
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    • pp.64-79
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    • 1994
  • In this study, terrain classification, which was done by using the quantitative classification parameters and suitable interpolation method was applied to improve the accuracy of digital elevation models, and to increase its practical use of aerial photogrammetry. A terrain area was classified into three groups using the quantitative classification parameters to the ratio of horizontal, inclined area, magnitude of harmonic vectors, deviation of vector, the number of breakline and proposed the suitable interpolation. Also, the accuracy of digital elevation models was improved in case of large grid intervals by applying combined interpolation suitable for each terrain group. As a result of this study, I have an algorithm to perform the classification of the topography in the area of interest objectively and decided optimal data interpolation scheme for given topography.

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PIV에서의 보간기법의 평가에 관한 연구 (A Study on the Evaluation of Interpolation Methods in PIV)

  • 최장운;조대한;최민선;이영호
    • Journal of Advanced Marine Engineering and Technology
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    • 제20권4호
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    • pp.90-100
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    • 1996
  • To maintain high spacial accuracy and rapid CPU time in interpolating data from grid to random position or inversely in PIV, proposed many technuques are compared and discussed mainly in terms of interpolating error and computing time. And artificial PIV atmosphere data is furnished by CFD result. First, for interpolation from grid to random position, multiquadric method gives the highest accuracy with the longest CPU time and Taylor series expansion methods give reasonable accuracy with less calculating load. Secondly, the sub-pixel resolution analysis in estimating the coordinates of the maximum correlation coefficients essential in the grey level correlation PIV reveal that 8-neighbours 2nd-order least square interpolation gives utmost accuracy in terms of the real flow conditions.

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PIV에서의 보간기법의 평가에 관한 연구 (A Study on the Evaluation of Interpolation Methods in PIV)

  • 최장운;조대환;최민선;이영호
    • Journal of Advanced Marine Engineering and Technology
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    • 제20권4호
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    • pp.412-412
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    • 1996
  • To maintain high spacial accuracy and rapid CPU time in interpolating data from grid to random position or inversely in PIV, proposed many technuques are compared and discussed mainly in terms of interpolating error and computing time. And artificial PIV atmosphere data is furnished by CFD result. First, for interpolation from grid to random position, multiquadric method gives the highest accuracy with the longest CPU time and Taylor series expansion methods give reasonable accuracy with less calculating load. Secondly, the sub-pixel resolution analysis in estimating the coordinates of the maximum correlation coefficients essential in the grey level correlation PIV reveal that 8-neighbours 2nd-order least square interpolation gives utmost accuracy in terms of the real flow conditions.

공간 및 시간준위 보간 특성곡선법의 비교연구 (A Comparative Study on Spatial and Temporal Line Interpolation of Characteristic Method)

  • 백중철;배덕효
    • 물과 미래
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    • 제29권1호
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    • pp.203-212
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    • 1996
  • 특성곡선이 통과하는 인접 시간준위에서의 3개 격자점을 이용한 시간준위 Lagrange 보간기법을 개발하여, 기존의 시간준위 보간기법인 Reachback 기법과 두가지 공간 보간기법, 즉 Upwind 기법과 3개의 공간 격자점을 이용한 공간 2차 보간기법과 함께 두가지 형태의 오염원 이송문제에 각각 적용 하므로써 공간 및 시간준위 보간기법에 의한 수치해의 정확도를 비교, 분석하였다. 본 연구결과에 의하면 동일한 차수의 보간기법을 비교할 경우, 공간보간 기법보다 시간 보간기법을 이용하면 수치분산 또는 수치진동이 적은 보다 정확한 수치해를 구할 수 있는 것으로 나타났다. 한편, 본 연구에서 제시한 기법은 기존 시간준위 보간기법에 의한 해의 장점을 포함하면서 정확도를 향상시킬 수 있는 것으로 나타났다.

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Quadrilateral Irregular Network for Mesh-Based Interpolation

  • Tae Beom Kim;Chihyung Lee
    • 지질공학
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    • 제33권3호
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    • pp.439-459
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    • 2023
  • Numerical analysis has been adopted in nearly all modern scientific and engineering fields due to the rapid and ongoing evolution of computational technology, with the number of grid or mesh points in a given data field also increasing. Some values must be extracted from large data fields to evaluate and supplement numerical analysis results and observational data, thereby highlighting the need for a fast and effective interpolation approach. The quadrilateral irregular network (QIN) proposed in this study is a fast and reliable interpolation method that is capable of sufficiently satisfying these demands. A comparative sensitivity analysis is first performed using known test functions to assess the accuracy and computational requirements of QIN relative to conventional interpolation methods. These same interpolation methods are then employed to produce simple numerical model results for a real-world comparison. Unlike conventional interpolation methods, QIN can obtain reliable results with a guaranteed degree of accuracy since there is no need to determine the optimal parameter values. Furthermore, QIN is a computationally efficient method compared with conventional interpolation methods that require the entire data space to be evaluated during interpolation, even if only a subset of the data space requires interpolation.

2차원 선형보간법을 이용한 OFDM MIMO 시스템에서의 채널 추정 (A Novel Channel Estimation using 2-Dimensional Linear Iinterpolation for OFDM MIMO systems)

  • 오태열;안성수;최승원
    • 디지털산업정보학회논문지
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    • 제7권3호
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    • pp.107-113
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    • 2011
  • An OFDMA(Orthogonal Frequency Division Multiple Access) includes a MIMO(Multi-Input Multi-Output) scheme for improving spectral efficiency and data throughput. Recognizing that the performance of MIMO system is heavily dependent upon the accuracy of channel estimation, we propose a novel channel estimation for the MIMO scheme based on OFDMA. Conventional interpolation-based channel estimation suffers from poor estimation error at specific subcarriers. Proposed scheme makes use of a planar interpolation instead of linear interpolation for those subcarriers of bad accuracy. Simulation results show that the proposed scheme improves the performance of MIMO system by improving the accuracy in channel estimation especially for the adverse subcarrier positions. It is observed that the proposed scheme outperforms the conventional method by about 2dB in terms of both mean squared error and overall bit error rate with a reasonable computational complexity.

지하공간통합지도의 정확도 향상을 위한 계측 데이터 분류 및 공간 보간 기법 적용성 분석 (Applicability Analysis of Measurement Data Classification and Spatial Interpolation to Improve IUGIM Accuracy)

  • 이상연;송기일;강경남;김우람;안준상
    • 한국지반공학회논문집
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    • 제38권10호
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    • pp.17-29
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    • 2022
  • 최근 지하 안전에 관한 다양한 이슈들로 인해 지하공간 또는 지하시설물의 관리 필요성이 대두대고 있어 지하공간 통합지도 활용이 필요한 실정이다. 지하공간통합지도는 지하공간개발 및 지하안전관리 등의 분야에 직접적으로 사용되고 있기 때문에, 정보의 최신성 및 정확성이 매우 중요하다. 본 연구에서는 지하공간통합지도에 정확성을 향상시키기 위해 지하공간통합지도에 저장된 데이터와 굴착현장에서 획득 가능한 계측데이터를 분류하고, 획득된 데이터를 활용하여 다양한 보간기법의 적용성을 평가하였다. 공간 보간은 보간기법 및 모델별 총 7 종의 공간보간결과를 교차검증을 통해 정량적 평가를 수행하였다. 교차검증 결과, NURBS, 크리깅 및 역거리가중치법 순으로 정확도가 감소하는 것으로 나타났다. 또한 크리깅의 경우 베리오그램 모델에 따라 정확도의 차이가 있었으나 미미하였고, 구형 베리오그램이 정확도가 가장 우수한 것으로 나타났다.

수치지형모형에 있어 지형의 분석과 조합보관법의 적용에 관한 연구 (A Study on the Application of Combined Interpolation and Terrain Classification in Digital Terrain Model)

  • 유복모;박운용;권현;문두열
    • 한국측량학회지
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    • 제8권2호
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    • pp.53-61
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    • 1990
  • 본 연구에서는 지형의 정량적 분석변수를 이용하여 지형을 분류하고, 지형에 따라 적절한 보간법을 적용하므로써 수치지형모형의 정확도 향상과 효용성을 높이는데 그 목적이 있다. 지형해석에 있어서 정량적 분류 변수를 이용하여 대상지역을 4개의 군집으로 분류하여 지형에 따른 경제적인 보간법을 적용하였으며 격자간격이 클 경우 각 지형군별로 보간법을 조합시킨 조합보간법을 적용하므로써 정확도를 향상시킬 수 있었다.

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기온감률 효과 적용에 따른 공간내삽기법의 기온 추정 정확도 비교 (Accuracy Comparison of Air Temperature Estimation using Spatial Interpolation Methods according to Application of Temperature Lapse Rate Effect)

  • 김용석;심교문;정명표;최인태
    • 한국기후변화학회지
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    • 제5권4호
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    • pp.323-329
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    • 2014
  • Since the terrain of Korea is complex, micro- as well as meso-climate variability is extreme by locations in Korea. In particular, air temperature of agricultural fields is influenced by topographic features of the surroundings making accurate interpolation of regional meteorological data from point-measured data. This study was carried out to compare spatial interpolation methods to estimate air temperature in agricultural fields surrounded by rugged terrains in South Korea. Four spatial interpolation methods including Inverse Distance Weighting (IDW), Spline, Ordinary Kriging (with the temperature lapse rate) and Cokriging were tested to estimate monthly air temperature of unobserved stations. Monthly measured data sets (minimum and maximum air temperature) from 588 automatic weather system(AWS) locations in South Korea were used to generate the gridded air temperature surface. As the result, temperature lapse rate improved accuracy of all of interpolation methods, especially, spline showed the lowest RMSE of spatial interpolation methods in both maximum and minimum air temperature estimation.