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Automatic Defect Detection and Grading of Single-Color Fruits Using HSV (Hue, Saturation, Value) Color Space 被引量:1
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作者 Saeideh Gorji Kandi 《Journal of Life Sciences》 2010年第7期39-45,共7页
Machine vision has been recently utilized for quality control of food and agricultural products, which was traditionally done by manual inspection. The present study was an attempt for automatic defect detection and s... Machine vision has been recently utilized for quality control of food and agricultural products, which was traditionally done by manual inspection. The present study was an attempt for automatic defect detection and sorting of some single-color fruits such as banana and plum. Fruit images were captured using a color digital camera with capturing direction of zero degree and under illuminant D65. It was observed that growing decay and time-aging made surface color changes in bruised parts of the object. 3D RGB and HSV color vectors as well as a single channel like H (hue), S (saturation), V (value) and grey scale images were applied for color quantization of the object. Results showed that there was a distinct threshold in the histogram of the S channel of images which can be applied to separate the object from its background. Moreover, the color change via the defect and time-aging is correctly distinguishable in the hue channel image. The effect of illumination, gloss and shadow of 3D image processing is less noticeable for hue data in comparison to saturation and value. The value of H channel was quantized to five groups based on the difference between each pixel value and the H value of a healthy object. The percentage of different degree of defects can be computed and used for grading the fruits. 展开更多
关键词 Machine vision HSV color space FRUIT GRADING defect detection.
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Performance evaluation of wavelet scattering network in image texture classification in various color spaces 被引量:2
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作者 伍家松 姜龙玉 +2 位作者 韩旭 Lotfi Senhadji 舒华忠 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期46-50,共5页
The optimized color space is searched by using the wavelet scattering network in the KTH_TIPS_COL color image database for image texture classification. The effect of choosing the color space on the classification acc... The optimized color space is searched by using the wavelet scattering network in the KTH_TIPS_COL color image database for image texture classification. The effect of choosing the color space on the classification accuracy is investigated by converting red green blue (RGB) color space to various other color spaces. The results show that the classification performance generally changes to a large degree when performing color texture classification in various color spaces, and the opponent RGB-based wavelet scattering network outperforms other color spaces-based wavelet scattering networks. Considering that color spaces can be changed into each other, therefore, when dealing with the problem of color texture classification, converting other color spaces to the opponent RGB color space is recommended before performing the wavelet scattering network. 展开更多
关键词 wavelet scattering network color texture classification color spaces opponent mechanism
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Low-dimensional multi-spectral space for color reproduction based on nonnegative constrained principal component analysis 被引量:1
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作者 王莹 曾平 +1 位作者 罗雪梅 谢琨 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期486-490,共5页
In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonne... In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonnegative constrained principal component analysis method is proposed to construct a low-dimensional multi-spectral space and accomplish the conversion between the new constructed space and the multispectral space. First, the reason behind the negative data is analyzed and a nonnegative constraint is imposed on the classic PCA. Then a set of nonnegative linear independence weight vectors of principal components is obtained, by which a lowdimensional space is constructed. Finally, a nonlinear optimization technique is used to determine the projection vectors of the high-dimensional multi-spectral data in the constructed space. Experimental results show that the proposed method can keep the reconstructed spectral data in [ 0, 1 ]. The precision of the space created by the proposed method is equivalent to or even higher than that by the PCA. 展开更多
关键词 spectral color science nonnegative constrained principal component analysis low-dimensional spectral space nonlinear optimization multi-spectral images spectral reflectance
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The Hjek-Rnyi Inequlity For Banach Space Valued Random Variable Sequences and Its Application 被引量:7
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作者 Gan Shixin Department of Mathematics,Wuhan University,Wuhan 430072,China 《Wuhan University Journal of Natural Sciences》 CAS 1997年第1期15-20,共6页
In this paper we prove the following Hajek Renyi inequality:Let 0<p≤1 ,then for any Banach space B , any L p integrable B valued random variable sequence {D n,n≥1} ,any real number sequence {b... In this paper we prove the following Hajek Renyi inequality:Let 0<p≤1 ,then for any Banach space B , any L p integrable B valued random variable sequence {D n,n≥1} ,any real number sequence {b n,n≥1} with 0<b n↑∞ ,any integer n≥1 ,there exits a constant C=C p>0 (only depending on p ) such thatP( sup j≥nji=1D ib j≥ε)≤Cε -p (∞j=n+1E‖D j‖ pb p j+nj=1E‖D j‖ pb p n) In the other direction,we prove some strong laws of large numbers and the integrability of the maximal functions for B valued random variable sequences by using this inequality and the Hajeck Renyi inequality we have obtained recently.Some known results are extended and improved. 展开更多
关键词 P smoothable space space of type P Banach space valued martingale strong law of large numbers integrability of the maximal function
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Biochemical Composition and Nutritional Value of Different Shell Color Strains of Pacific Oyster Crassostrea gigas 被引量:4
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作者 ZHU Yijing LI Qi +1 位作者 YU Hong KONG Lingfeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第4期897-904,共8页
The shell color of Pacific oyster(Crassostrea gigas) is a desirable trait; but the nutritional studies on C. gigas with different shell colors have not been conducted. Through successive selective breeding, five shell... The shell color of Pacific oyster(Crassostrea gigas) is a desirable trait; but the nutritional studies on C. gigas with different shell colors have not been conducted. Through successive selective breeding, five shell color strains of black(B), purple(P), orange(O), golden(G) and white(W) C. gigas have been developed. The aim of this study was to evaluate the chemical composition and nutritional value of five shell color strains and one commercial population with a common color. The biochemical composition including moisture, total protein, glycogen, ash, total fat, fatty acids(FA), amino acids and minerals was detected. The results indicated that the protein(50.76%–56.57%) was the major component. The content of glycogen showed a significant difference between orange shell and golden shell strains, as well as between commercial population and golden shell strain. In addition, all shell color strains contained a large amount of essential amino acids(12.20–14.15 g(100 g)^(-1)), of them leucine(2.81–3.29 g(100 g)^(-1)) and lysine(2.79–3.28 g(100 g)^(-1)) were predominant. The oysters were rich in polyunsaturated fatty acids(42.26%–45.24% of total fatty acid) with high levels of DHA(18.53%–21.16% of total fatty acid) and EPA(17.23%–18.68% of total fatty acid). Significant differences of mineral contents(Mg, Zn, Fe and Cu) were identified among the six populations. These results indicated that C. gigas with different shell colors presented rich nutritional value with high protein, glycogen, essential amino acids and polyunsaturated fatty acids. The biochemical composition obtained in this study is useful for selective breeding of C. gigas with different shell colors. 展开更多
关键词 CRASSOSTREA GIGAS BIOCHEMICAL composition NUTRITION value shell color selective breeding
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Color Measurement of Segmented Printed Fabric Patterns in Lab Color Space from RGB Digital Images 被引量:7
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作者 Charles Kumah Ning Zhang +1 位作者 Rafiu King Raji Ruru Pan 《Journal of Textile Science and Technology》 2019年第1期1-18,共18页
Colors of textile materials are the first parameter of quality evaluated by consumers and a key component considered in selecting printed fabric. In the textiles industry, digital printed fabric analysis is one of the... Colors of textile materials are the first parameter of quality evaluated by consumers and a key component considered in selecting printed fabric. In the textiles industry, digital printed fabric analysis is one of the basic elements in successfully utilizing a color mechanism scheme and objectively evaluating fabric color alterations. Precise color measurement, however, is mostly used in sample analysis and quality inspection which help to produce reproducible or similar product. It is important that for quality inspection, the color of the product should be measured as a necessary requirement of quality control whether the product is to be accepted or not. Presented in this study is an unsupervised segmentation of printed fabrics patterns using mean shift algorithm and color measurements over the segmented regions of printed fabric patterns. The results established a consistent and reliable color measurement of multiple color patterns and appearance with the established range without any interactions. 展开更多
关键词 color Measurement LAB color space RGB color space Region of INTEREST (ROI) Quality Control
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Deer Body Adaptive Threshold Segmentation Algorithm Based on Color Space 被引量:6
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作者 Yuheng Sun Ye Mu +4 位作者 Qin Feng Tianli Hu He Gong Shijun Li Jing Zhou 《Computers, Materials & Continua》 SCIE EI 2020年第8期1317-1328,共12页
In large-scale deer farming image analysis,K-means or maximum between-class variance(Otsu)algorithms can be used to distinguish the deer from the background.However,in an actual breeding environment,the barbed wire or... In large-scale deer farming image analysis,K-means or maximum between-class variance(Otsu)algorithms can be used to distinguish the deer from the background.However,in an actual breeding environment,the barbed wire or chain-link fencing has a certain isolating effect on the deer which greatly interferes with the identification of the individual deer.Also,when the target and background grey values are similar,the multiple background targets cannot be completely separated.To better identify the posture and behaviour of deer in a deer shed,we used digital image processing to separate the deer from the background.To address the problems mentioned above,this paper proposes an adaptive threshold segmentation algorithm based on color space.First,the original image is pre-processed and optimized.On this basis,the data are enhanced and contrasted.Next,color space is used to extract the several backgrounds through various color channels,then the adaptive space segmentation of the extracted part of the color space is performed.Based on the segmentation effect of the traditional Otsu algorithm,we designed a comparative experiment that divided the four postures of turning,getting up,lying,and standing,and successfully separated multiple target deer from the background.Experimental results show that compared with K-means,Otsu and hue saturation value(HSV)+K-means,this method is better in performance and accuracy for adaptive segmentation of deer in artificial breeding scenes and can be used to separate artificially cultivated deer from their backgrounds.Both the subjective and objective aspects achieved good segmentation results.This article lays a foundation for the effective identification of abnormal behaviour in sika deer. 展开更多
关键词 Artificial breeding color space deer body recognition image segmentation K-MEANS multi-target recognition OTSU
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Wide-Band Multi-spectral Space for Color Representation 被引量:2
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作者 Kurt Muenger 《Geo-Spatial Information Science》 2003年第2期69-74,共6页
This paper develops a wide-band multi-spectral space for color representationwith Aitken PCA algorithm. This novel mathematical space using the broad-band spectra matchingmethod aims at improving the accuracy of color... This paper develops a wide-band multi-spectral space for color representationwith Aitken PCA algorithm. This novel mathematical space using the broad-band spectra matchingmethod aims at improving the accuracy of color representation as well as reducing costs forprocessing and storing multi-spectral images. The results show that the space can present ourexperimental original spectral spaces (i. e. Munsell color matt and DIN-6164 color chips) with highefficiency, and that the spanning space with three eigenvectors can present the original space atmore than 98% CSCR, and when 5 eigenvectors are used it can cover almost the whole o-riginal spaces. 展开更多
关键词 color representation METAMERISM wide-band multispectral space PCA(principal component analysis)
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Paper Clinical Value of Color Doppler Ultrasonography in Diagnosis of Lower Extremity Arterial Disease of Diabetes Patients 被引量:2
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作者 Jianyu Zhang Haijiao Mao 《Journal of Biosciences and Medicines》 2020年第6期209-214,共6页
<div style="text-align:justify;"> <strong>Objective:</strong> To evaluate the diagnostic value of color Doppler ultrasound in the diagnosis of diabetic lower extremity vascular diseases. &l... <div style="text-align:justify;"> <strong>Objective:</strong> To evaluate the diagnostic value of color Doppler ultrasound in the diagnosis of diabetic lower extremity vascular diseases. <strong>Methods: </strong>48 patients with diabetic lower extremity vascular disease admitted in our hos-pital from September 2018 to September 2019 were included in the study and divided into the observation group, and another 48 patients with the same period of health examination in our hospital were included in the study and divided into the control group. Both groups used color Doppler ultrasound to detect the blood flow of lower extremity vessels. The incidence of blood flow, vascular diameter and stenosis, occlusion and arteriosclerosis of the lower extremity were observed. <strong>Results:</strong> The blood flow and vascular di-ameter of the lower extremity in the observation group were significantly lower than those in the control group (p < 0.05). The incidence of vascular stenosis, vascular occlusion, thrombus, intimal thickening and plaque in the observation group was 85.42%, 22.92%, 10.42% and 93.75% respectively, which was significantly higher than that in the control group was 10.42%, 0.00%, 0.00% and 14.58% (p < 0.05). The incidence of lower extremity vascular lesions in the observation group was significantly higher than that in the control group (p < 0.05). <strong>Conclusion:</strong> Color Doppler ultrasound is of high diagnostic value in the diagnosis of diabetic lower extremity vascular diseases, and can be used to determine the blood flow of the lower extremity and the inner diameter of popliteal artery, thigh artery, dorsalis pedis artery and so on. At the same time, it can also clearly show the specific situation of vascular occlusion, arteriosclerosis and thrombosis, which is of great signif-icance for the prevention and diagnosis of lower extremity vascular lesions, and can provide the basis for the treatment of lower extremity vascular lesions. </div> 展开更多
关键词 Super color Doppler Ultrasound Diabetic Complications Lower Extremity Vascular Disease Diagnostic value
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B-Implicit Contractive Conditions and Unique(Common) Fixed Points on Complex Valued Metric Spaces 被引量:2
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作者 PIAO Yong-jie 《Chinese Quarterly Journal of Mathematics》 2018年第2期212-220,共9页
A class B of complex functions is introduced and several existence theorems of unique(common) fixed points for mappings satisfying a B-implicit contraction are presented.Moreover, the existence results of common fixed... A class B of complex functions is introduced and several existence theorems of unique(common) fixed points for mappings satisfying a B-implicit contraction are presented.Moreover, the existence results of common fixed points for two mappings on a nonempty set with two complex valued metrics are provided. Our outcomes generalize and improve some known results, especially, for instance, Banach contraction principle, Chatterjea-type fixed point theorem and the corresponding fixed point theorems. 展开更多
关键词 Complex valued metric space (Common) Fixed point B-implicit contraction
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Composition Operators with Linear Fractional Symbols on Vector-Valued Bergman Spaces 被引量:1
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作者 WangMao-fa UuPei-de ZhouShao-bo 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03A期759-764,共6页
Let φ and ψ be linear fractional self\|maps of the unit disk D and X a separable Hilbert space. In this paper we completely characterize the weak compactness of the product operators of a composition operation C φ... Let φ and ψ be linear fractional self\|maps of the unit disk D and X a separable Hilbert space. In this paper we completely characterize the weak compactness of the product operators of a composition operation C φ with another one's adjoint C * ψ on the vector\|valued Bergman space B 1(X) for forms C φC * ψ and C * ψC φ. 展开更多
关键词 vector\|valued Bergman space composition operator linear fractional map angular derivative weak compactness
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A Study on the Influence of Luminance L* in the L*a*b* Color Space during Color Segmentation 被引量:1
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作者 Rodolfo Alvarado-Cervantes Edgardo M. Felipe-Riveron +1 位作者 Vladislav Khartchenko Oleksiy Pogrebnyak 《Journal of Computer and Communications》 2016年第3期28-34,共7页
In this paper an evaluation of the influence of luminance L* at the L*a*b* color space during color segmentation is presented. A comparative study is made between the behavior of segmentation in color images using onl... In this paper an evaluation of the influence of luminance L* at the L*a*b* color space during color segmentation is presented. A comparative study is made between the behavior of segmentation in color images using only the Euclidean metric of a* and b* and an adaptive color similarity function defined as a product of Gaussian functions in a modified HSI color space. For the evaluation synthetic images were particularly designed to accurately assess the performance of the color segmentation. The testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. From the results is obtained that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume. 展开更多
关键词 color Image Segmentation CIELAB color space L*a*b* color space color Metrics color Segmentation Evaluation Synthetic color Image Generation
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PERIODIC BOUNDARY VALUE PROBLEMS FOR NONLINEAR IMPULSIVEINTEGRODIFFERENTIAL EQUATIONS OF MIXED TYPE IN BANACH SPACES 被引量:1
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作者 韦忠礼 《Acta Mathematica Scientia》 SCIE CSCD 1997年第1期35-43,共9页
In this paper, the author obtains an existence theorem of minimal and maximal solutions for the periodic boundary value problems of nonlinear impulsive integrodifferential equations of mixed type in Banach space by me... In this paper, the author obtains an existence theorem of minimal and maximal solutions for the periodic boundary value problems of nonlinear impulsive integrodifferential equations of mixed type in Banach space by means of the monotone iterative technique and cone theory based on a comparison result. 展开更多
关键词 CE PN EPC PERIODIC BOUNDARY value PROBLEMS FOR NONLINEAR IMPULSIVEINTEGRODIFFERENTIAL EQUATIONS OF MIXED TYPE IN BANACH spaceS EI
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Atomic Decompositions of Weak Hardy Spaces of B-Valued Martingales 被引量:4
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作者 MA Tao LIU Peide 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第3期456-460,共5页
The atomic decompositions of weak Hardy spaces of Banach-space-valued martingales are given. With the help of the atomic decompositions, some inequalities for B-valued martingales are established in the case 0〈r≤1. ... The atomic decompositions of weak Hardy spaces of Banach-space-valued martingales are given. With the help of the atomic decompositions, some inequalities for B-valued martingales are established in the case 0〈r≤1. Here the results are connected closely with the p-uniform smoothness and q-uniform convexity of Banach spaces which the martingales take values in. 展开更多
关键词 atomic decomposition weak Hardy space B-valued martingale
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Circle Detection Based on HSI Color Space 被引量:1
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作者 MAOXia LIXing-xin XUEYu-li 《Computer Aided Drafting,Design and Manufacturing》 2005年第1期36-40,共5页
A method based on HSI color space is presented to solve the problem of circle detection from color images. In terms of the evaluation to the edge detection method based on intensity, the edge detection based on hue is... A method based on HSI color space is presented to solve the problem of circle detection from color images. In terms of the evaluation to the edge detection method based on intensity, the edge detection based on hue is chosen to process the color image, and the simplified calculation of hue transform is discussed. Then the algorithm of circle detection based on Canny edge detection is proposed. Due to the dispersive distribution of the detected result, Hough transformation and template smooth are used in circle detection, and the proposed method gives a quite good result. 展开更多
关键词 HSI color space edge detection circle detection Hough transformation
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Real Interpolation Between B-valued Martingale Hardy Spaces
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作者 YU Lin College of Mathematical Sciences, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 1999年第2期10-15,共6页
The interpolation spaces between Banach space valued martingale Hardy spaces, between Hardy and BMO spaces are identified respectively. Some results obtained here are connected closely with the convexity and smooth... The interpolation spaces between Banach space valued martingale Hardy spaces, between Hardy and BMO spaces are identified respectively. Some results obtained here are connected closely with the convexity and smoothness of the Banach space which the martingales take values in. 展开更多
关键词 Banach space valued martingale martingale space interpolation space geometry of Banach space
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OPERATOR-VALUED FOURIER MULTIPLIER THEOREMS ON TRIEBEL SPACES 被引量:1
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作者 步尚全 Kim Jin-Myong 《Acta Mathematica Scientia》 SCIE CSCD 2005年第4期599-609,共11页
The authors establish operator-valued Fourier multiplier theorems on Triebel spaces on R^N, where the required smoothness of the multiplier functions depends on the dimension N and the indices of the Triebel spaces. T... The authors establish operator-valued Fourier multiplier theorems on Triebel spaces on R^N, where the required smoothness of the multiplier functions depends on the dimension N and the indices of the Triebel spaces. This is used to give a sufficient condition of the maximal regularity in the sense of Triebel spaces for vector-valued Cauchy problems with Dirichlet boundary conditions. 展开更多
关键词 Operator-valued Fourier multiplier vector-valued Triebel space Fourier type vector-valued maximal inequality maximal regularity
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Points of Coincidence and Common Fixed Points for Ⅱ-Expansive Mappings on Complex Valued Metric Spaces
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作者 Yongjie Piao 《Analysis in Theory and Applications》 CSCD 2017年第4期366-374,共9页
Abstract. We use the two mappings satisfying II-expansive conditions on complex valued metric spaces to construct the convergent sequences and prove that the unique limit of the sequences is the point of coincidence o... Abstract. We use the two mappings satisfying II-expansive conditions on complex valued metric spaces to construct the convergent sequences and prove that the unique limit of the sequences is the point of coincidence or common fixed point of the two mappings. Also, we discuss the uniqueness of points of coincidence or common fixed points and give the existence theorems of unique fixed points. The obtained results generalize and improve the corresponding conclusions in references. 展开更多
关键词 Complex valued metric space II-expansive mapping Cauchy sequence point ofcoincidence common fixed point.
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Recursive State-space Model Identification of Non-uniformly Sampled Systems Using Singular Value Decomposition 被引量:2
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作者 王宏伟 刘涛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1268-1273,共6页
In this paper a recursive state-space model identification method is proposed for non-uniformly sampled systems in industrial applications. Two cases for measuring all states and only output(s) of such a system are co... In this paper a recursive state-space model identification method is proposed for non-uniformly sampled systems in industrial applications. Two cases for measuring all states and only output(s) of such a system are considered for identification. In the case of state measurement, an identification algorithm based on the singular value decomposition(SVD) is developed to estimate the model parameter matrices by using the least-squares fitting. In the case of output measurement only, another identification algorithm is given by combining the SVD approach with a hierarchical identification strategy. An example is used to demonstrate the effectiveness of the proposed identification method. 展开更多
关键词 Non-uniformly sampling system STATE-space model IDENTIFICATION SINGULAR value decomposition RECURSIVE algorithm
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EXISTENCE THEOREMS OF SOLUTIONS FOR TWO-POINT BOUNDARY VALUE PROBLEM OF SECOND ORDER ORDINARY DIFFERENTIAL EQUATIONS IN BANACH SPACES
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作者 张石生 王凡 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第2期99-108,共10页
By using partial order method. some existing theorems of solutions for two-point bouniary value problem of second order ordinary differenlial equations in Banach spaces are given.
关键词 two-point boundary value problem weakly sequentially complete Banach space normal cone
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