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The Construction of Statisticaly Self-similar Measures
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作者 Hu Dihe Department of Mathematics,Wuhan University,Wuhan 430072,China 《Wuhan University Journal of Natural Sciences》 CAS 1997年第1期21-26,共6页
We have studied statistically self similar measures together with statistically self similar sets in this paper.A special kind of statistically self similar measures has been constructed and a class of statisticall... We have studied statistically self similar measures together with statistically self similar sets in this paper.A special kind of statistically self similar measures has been constructed and a class of statistically self similar sets as well. 展开更多
关键词 statistically self similar random set statistically self similar measure Hausdorff measure Hausdorff metric DISTRIBUTION
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MIXED SELF-CONFORMAL MULTIFRACTAL MEASURES 被引量:1
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作者 Meifeng Dai 《Analysis in Theory and Applications》 2009年第2期154-165,共12页
Mixed multifractal analysis studies the simultaneous scaling behavior of finitely many measures. A self-conformal measure is a measure invariant under a set of conformal mappings. In this paper, we provide a descript.... Mixed multifractal analysis studies the simultaneous scaling behavior of finitely many measures. A self-conformal measure is a measure invariant under a set of conformal mappings. In this paper, we provide a descript.ion of the mixed multifractal theory of finitely many self-conformal measures. 展开更多
关键词 mixed multifractal self-conformal measure conformal iterated function system
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THE EXACT MEASURES OF A CLASS OF SELF-SIMILAR SETS ON THE PLANE
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作者 Zhiwei Zhu Zuoling Zhou 《Analysis in Theory and Applications》 2008年第2期160-182,共23页
Let S belong to R^2 be the attractor of the iterated function system {f1, f2, f3 } iterating on the unit equilateral triangle So. where fi(x) =λix + bi, i = 1,2, 3, x =(x1, x2), b1=(0, 0), b3=(1-λ3 /2,√3... Let S belong to R^2 be the attractor of the iterated function system {f1, f2, f3 } iterating on the unit equilateral triangle So. where fi(x) =λix + bi, i = 1,2, 3, x =(x1, x2), b1=(0, 0), b3=(1-λ3 /2,√3/2 (1-λ3)) This paper determines the exact Hausdorff measure, centred covering measure and packing measure of S under some conditions relating to the contraction parameter. 展开更多
关键词 self-similar set Hausdorff measure centred covering measure packing measure
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Research Progress on Self-Efficacy Level of Patients with Type 2 Diabetes Mellitus and Its Influencing Factors
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作者 Peiling Li Juanjuan Guo 《Open Journal of Preventive Medicine》 2024年第5期79-89,共11页
Self-efficacy plays an important role in the management of type 2 diabetes mellitus (T2DM) patients, and it runs through the whole process of diabetes treatment, which is conducive to controlling and delaying the occu... Self-efficacy plays an important role in the management of type 2 diabetes mellitus (T2DM) patients, and it runs through the whole process of diabetes treatment, which is conducive to controlling and delaying the occurrence and development of complications, as well as improving the quality of life of patients. This paper mainly describes the concept of self-efficacy, the current situation of self-efficacy of diabetic patients at home and abroad, the functional aspects and their influencing factors, so as to take relevant measures on how to improve self-efficacy. It aims to provide a theoretical basis for the development of self-efficacy interventions for patients with type 2 diabetes mellitus. 展开更多
关键词 Type 2 Diabetes self-EFFICACY Influencing Factors measures
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DECAY RATE OF FOURIER TRANSFORMS OF SOME SELF-SIMILAR MEASURES
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作者 高翔 马际华 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1607-1618,共12页
This paper is concerned with the Diophantine properties of the sequence {ξθn}, where 1 ≤ξ 〈 θ and θ is a rational or an algebraic integer. We establish a combinatorial proposition which can be used to study suc... This paper is concerned with the Diophantine properties of the sequence {ξθn}, where 1 ≤ξ 〈 θ and θ is a rational or an algebraic integer. We establish a combinatorial proposition which can be used to study such two cases in the same manner. It is shown that the decay rate of the Fourier transforms of self-similar measures μλ with λ = θ-1 as the uniform contractive ratio is logarithmic. This generalizes some results of Kershner and Bufetov-Solomyak, who consider the case of Bernoulli convolutions. As an application, we prove that μλ ahaost every x is normal to any base b ≥ 2, which implies that there exist infinitely many absolute normal numbers on the corresponding self-similar set. This can be seen as a complementary result of the well-known Cassels-Schmidt theorem. 展开更多
关键词 self-similar measures Fourier transforms decay rate normal numbers
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Non-Spectral Problem of Self-Affine Measures in R<sup>3</sup>
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作者 Yanbo Yuan 《Advances in Pure Mathematics》 2021年第8期717-734,共18页
The problems of determining the spectrality or non-spectrality of a measure have been received much attention in recent years. One of the non-spectral problems on <span style="white-space:nowrap;"><... The problems of determining the spectrality or non-spectrality of a measure have been received much attention in recent years. One of the non-spectral problems on <span style="white-space:nowrap;"><em>μ<sub>M,D</sub></em></span><sub> </sub>is to estimate the number of orthogonal exponentials in <em>L</em><sup>2</sup><span style="white-space:normal;">(</span><em>μ<sub>M,D<span style="white-space:normal;">)</span></sub></em>. In the present paper, we establish some relations inside the zero set <img src="Edit_2196df81-d10f-4105-a2a9-779f454a56c3.png" width="55" height="23" alt="" /> by the Fourier transform of the self-affine measure <em>μ<sub>M,D</sub></em>. Based on these facts, we show that <em>μ<sub>M,D</sub></em> is a non-spectral measure<em><sub> </sub></em>and there exist at most 4 mutually orthogonal exponential functions in <em style="white-space:normal;"><em style="white-space:normal;">L</em><sup style="white-space:normal;">2</sup><span style="white-space:normal;">(</span><span style="white-space:normal;"></span><em style="white-space:normal;">μ<sub>M,D)</sub></em></em>, where the number 4 is the best possible. This extends several known conclusions. 展开更多
关键词 Iterated Function System (IFS) self-Affine measure Orthogonal Exponentials
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Measurement Research Based on Bayesian Structural Equation Cognitive Model
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作者 Shuixian Fei Sanzhi Shi +4 位作者 Jixin Li Jiali Zheng Xinyi Yu Yifan Huang Xiang Li 《Journal of Applied Mathematics and Physics》 2024年第4期1163-1177,共15页
The Bayesian structural equation model integrates the principles of Bayesian statistics, providing a more flexible and comprehensive modeling framework. In exploring complex relationships between variables, handling u... The Bayesian structural equation model integrates the principles of Bayesian statistics, providing a more flexible and comprehensive modeling framework. In exploring complex relationships between variables, handling uncertainty, and dealing with missing data, the Bayesian structural equation model demonstrates unique advantages. Therefore, Bayesian methods are used in this paper to establish a structural equation model of innovative talent cognition, with the measurement of college students’ cognition of innovative talent being studied. An in-depth analysis is conducted on the effects of innovative self-efficacy, social resources, innovative personality traits, and school education, aiming to explore the factors influencing college students’ innovative talent. The results indicate that innovative self-efficacy plays a key role in perception, social resources are significantly positively correlated with the perception of innovative talents, innovative personality tendencies and school education are positively correlated with the perception of innovative talents, but the impact is not significant. 展开更多
关键词 Bayesian Structural Equation Model Innovative Talents measure of Cognition Innovative self-Efficacy Social Resources
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Self-calibration and Compensation of Setting Errors for Surface Profile Measurement of a Microstructured Roll Workpiece 被引量:3
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作者 GAO Wei XU Bin +2 位作者 TAKEISHI Toshiki SHIMIZU Yuki ITO So 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第1期14-22,共9页
Microstructured roll workpieces have been widely used as functional components in the precision industries. Current researches on quality control have focused on surface profile measurement of microstructured roll wor... Microstructured roll workpieces have been widely used as functional components in the precision industries. Current researches on quality control have focused on surface profile measurement of microstructured roll workpieces, and types of measurement systems and measurement methods have been developed. However, low measurement efficiency and low measurement accuracy caused by setting errors are the common disadvantages for surface profile measurement of microstructured roll workpieces. In order to shorten the measurement time and enhance the measurement accuracy, a method for self-calibration and compensation of setting errors is proposed for surface profile measurement of microstructured roll workpieces. A measurement system is constructed for the measurement, in which a precision spindle is employed to rotate the roll workpiece and an air-bearing displacement sensor with a micro-stylus probe is employed to scan the microstructured surface of the roll workpiece. The resolution of the displacement sensor is 0.14 nm and that of the rotary encoder of the spindle was 0.15r~. Geometrical and mathematical models are established for analyzing the influences of the setting errors of the roll workpiece and the displacement sensor with respect to the axis of the spindle, including the eccentric error of the roll workpiece, the offset error of the sensor axis and the zero point error of the sensor output. Measurement experiments are carded out on a roll workpiece on which periodic microstructures are a period of 133 i^m along the circumferential direction. Experimental results demonstrate the feasibility of the self-compensation method. The proposed method can be used to detect and compensate the setting errors without using any additional accurate artifact. 展开更多
关键词 measurement profile setting error self-CALIBRATION COMPENSATION microstructure roll workpiece
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The Exact Measure Functions of the Images for a Class of Self-Similar Processes 被引量:2
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作者 HUANG Li-hu LI Bing-zhang LIU Lu-qin (College of Mathematics and Computer Science, Wuhan University, Wuhan 430072, China) 《Wuhan University Journal of Natural Sciences》 CAS 2000年第1期1-6,共6页
Let X= (Ω, ■, ■_t, X_t,, θ_t, p~x) be a self-similar Markov process on (0,∞) with non-decreasing path. The exact Hausdorff and Packing measure functions of the image X([0,t] ) are obtained.
关键词 self-similar Markov process exact Hausdorff measure functions exact Packing measure function
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The Convergence of Statistically Self Similar Sets and the Upper Bound and Lower Bound of Hausdorff Measure
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作者 Hu Dihe 《Wuhan University Journal of Natural Sciences》 CAS 1997年第2期16-20,共5页
We constructed a class of self-similar sets and proved the convergence in this paper.Besides these,the upper bound and lower bound of Hausdorff measures of them were given too.
关键词 statistically self similar sets Hausdorff metric Hausdorff measure Polish space
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ON THE EXACT HAUSDORFF MEASURE OF A CLASS OF SELF-SIMILAR SETS SATISFYING OPEN SET CONDITION 被引量:2
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作者 Shaoyuan Xu Weiyi Su Zuoling Zhou 《Analysis in Theory and Applications》 2008年第1期93-100,共8页
In this paper, we provide a new effective method for computing the exact value of Hausdorff measures of a class of self-similar sets satisfying the open set condition (OSC). As applications, we discuss a self-simila... In this paper, we provide a new effective method for computing the exact value of Hausdorff measures of a class of self-similar sets satisfying the open set condition (OSC). As applications, we discuss a self-similar Cantor set satisfying OSC and give a simple method for computing its exact Hausdorff measure. 展开更多
关键词 self-similar set Hausdorff measure and Hausdorff dimension open set condition
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Measurement of Characteristic Self-Similarity and Self-Diversity for Complex Mechanical Systems
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作者 ZHOU Meili~1 LAI Jiangfeng~2 Hefei University of Technology,Hefei 230009,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期872-875,共4页
Based on similarity science and complex system theory,a new concept of characteristic self-diversity and corre- sponding relations between self-similarity and self-diversity for complex mechanical systems are presente... Based on similarity science and complex system theory,a new concept of characteristic self-diversity and corre- sponding relations between self-similarity and self-diversity for complex mechanical systems are presented in this paper.Methods of system self-similarity and self-diversity measure between main system and sub-system are studied.Numerical calculations show that the characteristic self-similarity and self-diversity measure method is validity.A new theory and method of self-similarity and self- diversity measure for complexity mechanical system is presented. 展开更多
关键词 COMPLEX mechanical system self-SIMILARITY measurE self-diversity measurE
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Measurement invariance and latent mean differences of the Chinese version physical activity self-efficacy scale across gender and education levels 被引量:1
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作者 Han Chen Jun Dai Yong Gao 《Journal of Sport and Health Science》 SCIE 2019年第1期46-54,共9页
Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has... Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has rarely been conducted in China. The current study aims to examine(1) the unidimensionality of a shortened Chinese version of PA self-efficacy scale(S-PASESC);(2) the measurement invariance of S-PASESC across gender and levels of education;(3) the latent factor mean difference between gender and levels of education;(4) the direct effects of self-efficacy on PA by different gender and education levels; and(5) the comparisons of the direct effects of self-efficacy on PA across gender and education levels.Methods: The participants were 5 th through 11 th grade public school students recruited from 7 cities located in different geographic regions of China. The final data include a total of 3003 participants(49.7% boys) who have completed the scales.Results: Confirmatory factor analysis(CFA) test supported the unidimensionality of S-PASESC. The S-PASESC is invariant across gender and 3 levels of education at both configural, full metric, and full scalar levels. Findings from latent mean comparisons showed that boys reported higher PA self-efficacy than girls. Students' perceived PA self-efficacy tend to decrease from elementary to high school. Finally, self-efficacy positively related to PA by groups of different gender and education levels and the relationship between self-efficacy and PA is stronger among middle school boys than girls.Conclusion: Findings suggest S-PASESC is a valid scale for measuring Chinese students' PA self-efficacy. 展开更多
关键词 Chinese adolescents Education levels Factor analysis GENDER LATENT mean comparison measurEMENT INVARIANCE Physical activity self-EFFICACY scale
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Self-tuning weighted measurement fusion Kalman filter and its convergence 被引量:2
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作者 Chenjian RAN,Zili DENG (Department of Automation,Heilongjiang University,Harbin Heilongjiang 150080,China) 《控制理论与应用(英文版)》 EI 2010年第4期435-440,共6页
For multisensor systems,when the model parameters and the noise variances are unknown,the consistent fused estimators of the model parameters and noise variances are obtained,based on the system identification algorit... For multisensor systems,when the model parameters and the noise variances are unknown,the consistent fused estimators of the model parameters and noise variances are obtained,based on the system identification algorithm,correlation method and least squares fusion criterion.Substituting these consistent estimators into the optimal weighted measurement fusion Kalman filter,a self-tuning weighted measurement fusion Kalman filter is presented.Using the dynamic error system analysis (DESA) method,the convergence of the self-tuning weighted measurement fusion Kalman filter is proved,i.e.,the self-tuning Kalman filter converges to the corresponding optimal Kalman filter in a realization.Therefore,the self-tuning weighted measurement fusion Kalman filter has asymptotic global optimality.One simulation example for a 4-sensor target tracking system verifies its effectiveness. 展开更多
关键词 Multisensor weighted measurement fusion Fused parameter estimator Fused noise variance estimator self-tuning fusion Kalman filter Asymptotic global optimality CONVERGENCE
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A Local Property of Hausdorff Centered Measure of Self-Similar Sets
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作者 Zhiwei Zhu Zuoling Zhou 《Analysis in Theory and Applications》 2014年第2期164-172,共9页
We analyze the local behavior of the Hausdorff centered measure for self- similar sets. If E is a self-similar set satisfying the open set condition, thenC^s(E∩B(x,r))≤(2r)^sfor all x ∈ E and r〉 0, where Cs ... We analyze the local behavior of the Hausdorff centered measure for self- similar sets. If E is a self-similar set satisfying the open set condition, thenC^s(E∩B(x,r))≤(2r)^sfor all x ∈ E and r〉 0, where Cs denotes the s-dimensional Hausdorff centered measure. The above inequality is used to obtain the upper bound of the Hausdorff centered measure. As the applications of above inequality, We obtained the upper bound of the Hausdorff centered measure for some self-similar sets with Hausdorff dimension equal to 1, and prove that the upper bound reach the exact Hausdorff centered measure. 展开更多
关键词 Hausdorff centered measure Hausdorff measure self-similar sets.
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HAUSDORFF MEASURE OF UNIFORM SELF-SIMILAR FRACTALS
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作者 Wolfgang Kreitmeier 《Analysis in Theory and Applications》 2010年第1期84-100,共17页
Let d ≥ 1 be an integer and E a self-similar fractal set, which is the attractor of a uniform contracting iterated function system (UIFS) on R^d. Denote by D the Hausdorff dimension, by H^D(E) the Hausdorff measu... Let d ≥ 1 be an integer and E a self-similar fractal set, which is the attractor of a uniform contracting iterated function system (UIFS) on R^d. Denote by D the Hausdorff dimension, by H^D(E) the Hausdorff measure and by diam(E) the diameter of E. If the UIFS is parametrised by its contracting factor c, while the set ω of fixed points of the UIFS does not depend on c, we will show the existence of a positive constant depending only on ω, such that the Hausdorff dimension is smaller than one and H^O(E) = diam(E)^D if c is smaller than this constant. We apply our result to modified versions of various classical fractals. Moreover, we present a parametrised UIFS, where ω depends on c and show the inequatily H^D(E) 〈 diam(E)^D, if c is small enough. 展开更多
关键词 self-similar set Hausdorff measure
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Robustness self-testing of states and measurements in the prepare-and-measure scenario with 3 → 1 random access code
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作者 Shi-Hui Wei Fen-Zhuo Guo +1 位作者 Xin-Hui Li Qiao-Yan Wen 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期144-151,共8页
Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(... Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(2018)].They realized the self-testing of preparations and measurements in an N → 1(N ≥ 2) random access code(RAC), and provided robustness bounds in a 2 → 1 RAC.Since all N → 1 RACs with shared randomness are combinations of 2 → 1 and 3 → 1 RACs, the3 → 1 RAC is just as important as the 2 → 1 RAC.In this paper, we find a set of preparations and measurements in the3 → 1 RAC, and use them to complete the robustness self-testing analysis in the prepare-and-measure scenario.The method is robust to small but inevitable experimental errors. 展开更多
关键词 ROBUSTNESS self-TESTING prepare-and-measure SCENARIO 3 1 random access CODE
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Sub-external cavity effect and elimination method in laser self-mixing interference wave plate measurement system
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作者 牛海莎 牛燕雄 宋建军 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期349-354,共6页
Laser self-mixing interference(SMI) wave plate measurement method is a burgeoning technique for its simplicity and efficiency. But for the non-coated sample, the reflected light from the surface can seriously affect... Laser self-mixing interference(SMI) wave plate measurement method is a burgeoning technique for its simplicity and efficiency. But for the non-coated sample, the reflected light from the surface can seriously affect the measurement results.To analyze the reason theoretically, a self-consistent model for laser operation with a sub-external and an external cavity is established, and the sub-external cavity formed by the sample and a cavity mirror is proved to be the main error source.A synchronous tuning method is proposed to eliminate the sub-external cavity effect. Experiments are carried out on the synchronously tuning double external cavities self-mixing interference system, and the error of the system is in the range of -0.435°~0.387° compared with the ellipsometer. The research plays an important role in improving the performance and enlarging the application range of the laser self-mixing interference system. 展开更多
关键词 self-mixing interference non-coated wave plate measurement self-consistent model
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A Self-Mixing Microvibration Measurement System of a π-Phase Shifted DFB Fiber Laser
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作者 Rong Xiang Chuxia Chen +2 位作者 Bing Kong Qiusan Hong Liang Lu 《Optics and Photonics Journal》 CAS 2022年第12期269-282,共14页
Recently, with the rapid development of precision machining, microvibration measurement is required for the manufacturing and installation of parts and components. In this paper, a self-mixing microvibration measureme... Recently, with the rapid development of precision machining, microvibration measurement is required for the manufacturing and installation of parts and components. In this paper, a self-mixing microvibration measurement system of a π-phase shifted Distributed feedback (DFB) fiber laser is introduced. An all-fiberized configuration Er<sup>3+</sup>-Yb<sup>3+</sup> co-doped DFB fiber laser was used as light source, in which an active π-phase shifted fiber Bragg grating (FBG) was wrote on Er<sup>3+</sup>-Yb<sup>3+</sup> co-doped fiber. Using this, it can easily get a single-mode lasing with narrow linewidth. Experimental results demonstrate that the amplitude of vibration can be achieved down to λ/5 without any modulation parts while utilizing the reflecting mirror. It is in good agreement with the theoretical analysis and very helpful in proving sensitivity and stability of the measurement system. In addition, remote vibration measurement with a distance of 20 km is also realized with this system. 展开更多
关键词 self-MIXING Distributed Feedback Fiber Laser Microvibration measurement Remote Vibration measurement
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Self-tuning measurement fusion white noise deconvolution estimator with correlated noises
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作者 Xiaojun Sun Zili Deng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期666-674,共9页
For the multisensor linear discrete time-invariant stochastic systems with correlated noises and unknown noise statistics,an on-line noise statistics estimator is presented by using the correlation method.Substituting... For the multisensor linear discrete time-invariant stochastic systems with correlated noises and unknown noise statistics,an on-line noise statistics estimator is presented by using the correlation method.Substituting it into the steady-state Riccati equation,the self-tuning Riccati equation is obtained.Using the Kalman filtering method,based on the self-tuning Riccati equation,a self-tuning weighted measurement fusion white noise deconvolution estimator is presented.By the dynamic error system analysis(DESA) method,it is proved that the self-tuning fusion white noise deconvolution estimator converges to the optimal fusion steadystate white noise deconvolution estimator in a realization,so that it has the asymptotic global optimality.A simulation example for Bernoulli-Gaussian input white noise shows its effectiveness. 展开更多
关键词 multisensor information fusion measurement fusion self-tuning fuser white noise deconvolution asymptotic global optimality Kalman filtering convergence.
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