The decomposition of mixed pixels in Moderate Resolution Imaging Spectroradiometer (MODIS) images is essential for the application of MODIS data in many fields. Many existing methods for unmixing mixed pixels use prin...
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The decomposition of mixed pixels in Moderate Resolution Imaging Spectroradiometer (MODIS) images is essential for the application of MODIS data in many fields. Many existing methods for unmixing mixed pixels use principal component analysis to reduce the dimensionality of the image data and require the extraction of endmember spectra. We propose the pixel spectral unmixing index (PSUI) method for unmixing mixed pixels in MODIS images. In this method, a set of third-order bernstein basis functions is applied to reduce the dimensionality of the image data and characterize the spectral curves of the mixed pixels in a MODIS image, and then the derived PSUIs (i.e., the coefficients of the basisfunctions) are calibrated by means of the abundance values of the ground features from the Landsat Enhanced Thematic Mapper Plus (ETM+)/Operational Land Imager (OLI) classification images corresponding to the date and region of the MODIS image. The proposed method was tested on MODIS and ETM+/OLI images, and it obtained satisfying unmixing results. We compared the PSUI method with conventional methods, including the pixel purity index, the N-finder algorithm, the sequential maximum angle convex cone, and vertex component analysis and found that the PSUI method outperformed the other four methods. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License.
bernstein basis functions are used extensively in geometric modeling for their excellent merits. In this paper, a new 8-node assumed stress quasi-conforming plane element is proposed by using bernstein basis functions...
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bernstein basis functions are used extensively in geometric modeling for their excellent merits. In this paper, a new 8-node assumed stress quasi-conforming plane element is proposed by using bernstein basis functions. Firstly, the fundamental analytical solutions, which satisfy both the equilibrium and the compatibility relations of plane stress problem are used as the initial assumed stress of the element. Then the stress-function matrix is adopted as the weighted function to weaken the strain-displacement equations. Finally, the bernstein polynomials are chosen as string-net functions on the boundary of the element for the process of strain integration. The formulations of the element are simple and concise, and the element is immune to the distorted mesh, which can be used to the mesh shape degenerates into a triangle or concave quadrangle and curved-side element. The characteristics of bernstein polynomials to approximate models' geometry accuracy make the element competitive when compared with other solutions, especially for the curved-edge structures, which is proven by the numerical tests.
In this paper, a new set of bernstein type basisfunctions with 3 parameters is introduced. The properties of these basisfunctions are studied. A new kind of Bézier like curves with 3 parameters is defined based...
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In this paper, a new set of bernstein type basisfunctions with 3 parameters is introduced. The properties of these basisfunctions are studied. A new kind of Bézier like curves with 3 parameters is defined based on the new basisfunctions. The new curve not only holds many practical geometrical properties of Bézier curve, but also its shape can be adjusted totally or locally by changing values of the parameters. Finally, some application examples of the new curve are presented.
We give some alternative forms of the generating functions for the bernstein basis functions. Using these forms, we derive a collection of functional equations for the generating functions. By applying these equations...
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We give some alternative forms of the generating functions for the bernstein basis functions. Using these forms, we derive a collection of functional equations for the generating functions. By applying these equations, we prove some identities for the bernstein basis functions. Integrating these identities, we derive a variety of identities and formulas, some old and some new, for combinatorial sums involving binomial coefficients, Pascal's rule, Vandermonde's type of convolution, the Bernoulli polynomials, and the Catalan numbers. Copyright (C) 2014 John Wiley & Sons, Ltd.
With the help of the Cox-de Boor recursion formula and the recurrence relation of the bernstein polynomials, two categories of recursive algorithms for calculating the conversion matrix from an arbitrary non-uniform B...
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With the help of the Cox-de Boor recursion formula and the recurrence relation of the bernstein polynomials, two categories of recursive algorithms for calculating the conversion matrix from an arbitrary non-uniform B-spline basis to a bernstein polynomial basis of the same degree are presented. One is to calculate the elements of the matrix one by one, and the other is to calculate the elements of the matrix in two blocks. Interestingly, the weights in the two most basic recursion formulas are directly related to the weights in the recursion definition of the B-spline basisfunctions. The conversion matrix is exactly the B & eacute;zier extraction operator in isogeometric analysis, and we obtain the local extraction operator directly. With the aid of the conversion matrix, it is very convenient to determine the B & eacute;zier representation of NURBS curves and surfaces on any specified domain, that is, the isogeometric B & eacute;zier elements of these curves and surfaces.
The aim of this paper is to study generating functions for the coefficients of the classical superoscillatory function associated with weak measurements. We also establish some new relations between the superoscillato...
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The aim of this paper is to study generating functions for the coefficients of the classical superoscillatory function associated with weak measurements. We also establish some new relations between the superoscillatory coefficients and many well-known families of special polynomials, numbers, and functions such as bernstein basis functions, the Hermite polynomials, the Stirling numbers of second kind, and also the confluent hypergeometric functions. Moreover, by using generating functions, we are able to develop a recurrence relation and a derivative formula for the superoscillatory coefficients.& COPY;2023 Elsevier B.V. All rights reserved.
In this study, a robust unconditionally stable method for linear analysis of structures based on Bezier curves and bernstein polynomials is proposed. The Bezier curve is used as interpolation function and bernstein ba...
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In this study, a robust unconditionally stable method for linear analysis of structures based on Bezier curves and bernstein polynomials is proposed. The Bezier curve is used as interpolation function and bernstein basis functions are applied for interpolation. The spectral radius, period elongation and amplitude decay are investigated for stability analysis, numerical dispersion and dissipation of proposed method, and results are compared with other methods that are the best in these properties. It is also shown that the behavior of the proposed method in analysis of finite element system is effective and reliable. To show the robustness and features of proposed method, a challenging problem with a very stiff and flexible response, a Howe truss under impact load, a frame under harmonic loading and a rectangular domain in plane strain condition are considered, and derived results are compared with references solutions and other results reported in the literature. (C) 2017 Elsevier Ltd. All rights reserved.
In [M. M. Malakiyeh, S. Shojaee and S. Hamzehei-Javaran, Development of a direct time integration method based on Bezier curve and 5th-order Berstein basis function, Comput. Struct. 194 (2108) 15-31] an unconditionall...
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In [M. M. Malakiyeh, S. Shojaee and S. Hamzehei-Javaran, Development of a direct time integration method based on Bezier curve and 5th-order Berstein basis function, Comput. Struct. 194 (2108) 15-31] an unconditionally stable implicit time-integration method using the Bezier curve was proposed for solving structural dynamic problems. In this study, a new class of the previous algorithm is presented by using the bernstein polynomials and the Bezier curve as the interpolation functions for solving the equations of motion with the possibility of using large time steps. The spectral radius, period elongation, amplitude decay and overshooting of the present method are investigated and compared with some other methods. To show the high-performance, robustness and validity of this method, five numerical examples are presented. The theoretical analysis and numerical examples show that the proposed method has low dissipation in the lower modes and high dissipation in the higher modes in comparison with the other methods reported in the literature.
In this paper, we construct a class of bernstein basis functions with a shape parameter of the same degree by extending definition interval of the classical bernstein basis functions to be dynamic. Then, we define the...
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In this paper, we construct a class of bernstein basis functions with a shape parameter of the same degree by extending definition interval of the classical bernstein basis functions to be dynamic. Then, we define the corresponding Bezier curve based on the introduced basisfunctions. The new curve not only has most properties of the classical Bezier curve, but also can be adjusted in shape by altering the value of the shape parameter when the control points are remained unchanged. The proposed curve is simpler than some existing similar models, which is a novel extension of the Bezier curve.
In this paper, an implicit time integration method based on Bezier curves and bernstein polynomials for analysis of structures is presented. Unconditional stability and accuracy comparable to other methods such as New...
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