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The effect of the distribution of measurement points around the node on the accuracy of interpolation of the digital terrain model

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JOURNAL OF GEOGRAPHICAL SYSTEMS 2013年第4期15卷 513-535页

作者： Gosciewski, Dariusz Univ Warmia & Mazury Inst Geodesy Fac Geodesy & Land Management PL-10957 Olsztyn Poland

Contemporary land information systems allow the generation of models of numerical surfaces by applying a number of interpolation algorithms. The appropriate selection of measurement points included in the calculations is one of the key factors influencing the quality and accuracy of interpolation. Properly selected points contribute to improving the accuracy of the generated surface models and to shortening the computation process. This paper analyzes the effect of the location and density of measurement points on the accuracy of interpolation surfaces in view of the morphological differentiation of the generated models.

关键词： Digital terrain model GRID structure interpolation algorithms

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A fast frequency-domain interpolation method for the evaluation of the frequency and amplitude of spectral components

A fast frequency-domain interpolation method for the evaluat...

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International Instrumentation and Measurement Technology Conference (I2MTC)

作者： Ferrero, Alessandro Salicone, Simona Politecn Milan Dipartimento Elettrotecn I-20133 Milan Italy

ISBN: (纸本)9781424428335

The evaluation of the spectral components of a signal by means of a DFT or FFT algorithm is subject to leakage errors whenever the sampling frequency is not coherent with the signal frequency. Smoothing windows are used to mitigate these errors, and interpolation methods are applied, in the frequency domain, to reduce these errors further on. However, if cosine windows are employed, closed-form formulas for the evaluation of the harmonic frequencies can be used only with second-order windows, while approximated formulas have to be used in the other cases. In both cases, a high computation burden is required. This paper proposes a fast interpolation method, independent of the window type and order, based on suitable look-up tables. Experimental results are reported and the accuracy is discussed, proving that the method provides results as good as those obtained with other methods, without requiring the same high computation burden.

关键词： interpolation algorithms Cosine windows FFT

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NURBS Piecewise interpolation Algorithm Based on Discrete S-Type Velocity Planning 31

NURBS Piecewise Interpolation Algorithm Based on Discrete S-...

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31st Chinese Control And Decision Conference (CCDC)

作者： Shi Bu-Hai Jiang Tong South China Univ Technol Sch Automat Sci & Engn Guangzhou 510641 Peoples R China

ISBN: (纸本)9781728101057

In order to make the 6-axis robot capable of processing NURBS curves, this paper firstly analyzes the recursive expressions of the NURBS curve and the calculation method of interpolation points, and proposes a new discrete S-type speed planning algorithm. In addition, to achieve the contour accuracy of NURBS and overcome the shortcomings of the feed-speed oscillation and hysteresis in the adaptive algorithm based an chord error, a segmented discrete S-type velocity planning algorithm for NURBS curve is proposed. The algorithm segmented the NURBS curve at the paint of extreme curvature, and discrete S-type velocity planning algorithm was applied to the segmented curve respectively, thus achieving a better control of the chord error under continuous acceleration. Finally, the NURBS Trident curve it used as an example to simulate and compare different interpolation algorithms in Matlab.

关键词： 6-axis robot NURBS interpolation algorithms

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An improved Hibbard interpolation algorithm based on edge judgement

An improved Hibbard interpolation algorithm based on edge ju...

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International Conference on algorithms, High Performance Computing, and Artificial Intelligence (AHPCAI)

作者： Xu, Tianzhuo Yu, Minghao Lanzhou Univ Sch Informat Sci & Engn Lanzhou 730107 Gansu Peoples R China Jilin Univ Sch Software Engn Zhuhai Coll Nanning 530000 Guangxi Peoples R China

ISBN: (数字)9781510651890

ISBN: (纸本)9781510651890;9781510651883

Traditional digital cameras use a Bayer array and image interpolation approach to restore a full-colour image. But there is only one-color sampling on each pixel, and the restoration of other colours on each pixel needs to be achieved through the CFA interpolation algorithms. Most algorithms have some distortions, including Zipper Effect, moire, false color, etc. For solving the problems, we proposed a novel algorithm for color image interpolation. This algorithm is based on the Hibbard algorithm and is leveraged for edge judgement. Furthermore, the algorithm involves two successive steps. The first step is to determine the direction of the edge by judging the difference in each direction. In contrast, the second step uses subsequent processing methods to improve the recovery effect of pictures. Experimental results show that compared with the Hibbard algorithm, the algorithm we proposed in this paper performs better under multiple indicators on image processing tasks.

关键词： image interpolation algorithms judgement

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Application of selected statistical coefficients to accuracy analysis on surface interpolation models 7

Application of selected statistical coefficients to accuracy...

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7th International Conference on Environmental Engineering

作者： Gosciewski, Dariusz Univ Warmia & Mazury Olsztyn Fac Geodesy & Land Management Inst Geodesy PL-10957 Olsztyn Poland

ISBN: (纸本)9789955282631

The majority of GIS type software systems allow generating the digital terrain models on the basis of the regular GRID type network of squares. The accuracy of such a model depends mainly on the choice of interpolation algorithms and their computation parameters. Comparison of quality and accuracy of the interpolation models generated by applying different algorithms is becoming an important issue. The paper presents a comparison of accuracy of terrain models generated by application of five interpolation algorithms. The analysis was based on the theoretical model represented by the mathematical surface generated using the function of two variables. Selected statistical coefficients and differential diagram of errors distribution were applied for interpolation models accuracy comparison. The matching accuracy of interpolation surface and the standard surface was also investigated. Results of analysis of the values determined by statistical coefficients supported with differential diagrams allowed comprehensive comparison of accuracy of interpolation algorithms and identification of the most accurate among them.

关键词： interpolation algorithms statistical coefficients differential diagrams accuracy analysis

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AN ALGORITHM FOR THE TRIANGULATION OF ARBITRARILY DISTRIBUTED POINTS - APPLICATIONS TO VOLUME ESTIMATE AND TERRAIN FITTING

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COMPUTERS & GEOSCIENCES 1991年第7期17卷 859-874页

作者： MACEDONIO, G PARESCHI, MT IBM CORP CTR RIC I-56100 PISA ITALY

An algorithm (and the relative C program) for the triangulation of a set of distinct arbitrarily distributed points is proposed. The set of triangles satisfies the condition of maximum smallest angles (MAX-MIN angle criterion). Some applications are presented about the reconstruction of the volume between geological horizons and about the interpolation of bivariate data, when function values are available at irregularly-spaced data points.

关键词： DELAUNAY TRIANGULATION VORONOI TESSELLATION VOLUME RECONSTRUCTION interpolation algorithms

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Numerical research on lid-driven cavity flows using a three-dimensional lattice Boltzmann model on non-uniform meshes

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Science China(Technological Sciences) 2013年第9期56卷 2178-2187页

作者： TANG XueLin SU YanWen WANG FuJun LI LinWei College of Water Resources and Civil Engineering China Agricultural University

A lattice Boltzmann model combined with curvilinear coordinate is proposed for lid-driven cavity three-dimensional (3D) flows. For particle velocity distribution, the particle collision process is performed in physical domain, and the particle streaming process is carried out in the corresponding computational domain, which is transferred from the physical domain using interpolation method. For the interpolation calculation, a second-order upwind interpolation method is adopted on internal lattice nodes in flow fields while a second-order central interpolation algorithm is employed at neighbor-boundary lattice nodes. Then the above-mentioned model and algorithms are used to numerically simulate the 3D flows in the lid-driven cavity at Reynolds numbers of 100, 400 and 1000 on non-uniform meshes. Various vortices on the x-y, y-z and x-z symmetrical planes are successfully predicted, and their changes in position with the Reynolds number increasing are obtained. The velocity profiles of u component along the vertical centerline and w component along the horizontal centerline are both in good agreement with the data in literature and the calculated results on uniform meshes. Besides, the velocity vector distributions on various cross sections in lid-driven cavity predicted on non-uniform meshes are compared with those simulated on uniform meshes and those in the literature. All the comparisons and validations show that the 3D lattice Boltzmann model and all the numerical algorithms on non-uniform meshes are accurate and reliable to predict effectively flow fields.

关键词： lattice Boltzmann model interpolation algorithms body-fitted meshes lid-driven cavity flows

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New developments in state estimation for nonlinear systems

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AUTOMATICA 2000年第11期36卷 1627-1638页

作者： Norgaard, M Poulsen, NK Ravn, O Tech Univ Denmark Dept Math Modelling DK-2800 Lyngby Denmark Tech Univ Denmark Dept Automat DK-2800 Lyngby Denmark

State estimators for nonlinear systems are derived based on polynomial approximations obtained with a multi-dimensional interpolation formula. It is shown that under certain assumptions the estimators perform better than estimators based on Taylor approximations. Nevertheless, the implementation is significantly simpler as no derivatives are required. Thus, it is believed that the new state estimators can replace well-known estimators, such as the extended Kalman filter (EKF) and its higher-order relatives, in most practical applications. (C) 2000 Elsevier Science Ltd. All rights reserved.

关键词： state estimation nonlinear filters interpolation algorithms multivariable polynomials extended Kalman filters parameter estimation

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Predictive algorithms for mobility and device lifecycle management in Cyber-Physical Systems

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EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING 2016年第1期2016卷 1页

作者： Bordel Sanchez, Borja Alcarria, Ramon Sanchez de Rivera, Diego Sanchez-Picot, Alvaro Univ Politecn Madrid Dept Telemat Syst Engn Ave Complutense 30 E-28040 Madrid Spain Univ Politecn Madrid Dept Topog Engn & Cartog Campus Sur Madrid 28031 Spain

Cyber-Physical Systems (CPS) are often composed of a great number of mobile, wireless networked devices. In order to guarantee the system performing, management policies focused on becoming transparent to high-level applications, the changes in the hardware platform have to be implemented. However, traditional reactive methodologies and basic proposed predictive solutions are not valid either due to the extremely dynamical behavior of CPS or because the high number of involved devices prevents fulfill the timing requirements. Therefore, in this paper, we present an advance predictive solution for managing the mobility and device lifecycle, being able to meet all requirements of CPS. The solution is based on an infinite loop, which calculates, in each iteration, a sequence of future system states using a CPS simulator and interpolation algorithms. Furthermore, an experimental validation is provided in order to determine the performing of the proposed solution.

关键词： Cyber-Physical Systems Mobility management Device lifecycle Predictive models CPS simulation interpolation algorithms

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Drag of Tandem Spheroids in Power-Law Fluids at Moderate Reynolds Numbers

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INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 2013年第33期52卷 11773-11778页

作者： Rathore, A. S. Chaitanya, P. Kishore, Nanda Indian Inst Technol Guwahati Dept Chem Engn Gauhati 781039 Assam India

The relative motion between a power-law fluid and two tandem spheroid particles was investigated numerically. The field equations that govern this problem were solved using a commercial computational-fluid-dynamics-based solver. The semi-implicit method for pressure-linked equations (SIMPLE) algorithm and the quadratic upstream interpolation for convective kinematics (QUICK) scheme for convective terms were used. The solver was thoroughly benchmarked through domain and grid studies. Further, extensive new results are presented for the following ranges of conditions: Reynolds number (Re), 1-200;particle aspect ratio (e), 0.5-2;power-law index (n), 0.4-1.6;and interparticle distance (S), 2-5. The main focus of this work was to report the effects of these parameters on the streamlines, surface viscosity, and drag coefficients of the tandem particles. The dependence of the average drag coefficient on the power-law index and Reynolds number had a crossover Reynolds number that was found to be a strong function of the particle aspect ratio and the interparticle distance. Below this crossover Reynolds number, the average drag coefficient increased with decreasing power-law index, whereas for Reynolds numbers greater than the crossover Reynolds number, the average drag coefficient decreased with decreasing power-law index.

关键词： REYNOLDS number RELATIVE motion EINSTEIN field equations COMPUTATIONAL fluid dynamics interpolation algorithms DRAG coefficient

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