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AN improved algorithm FOR DPIV CORRELATION ANALYSIS

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Journal of Hydrodynamics 2007年第1期19卷 62-67页

作者： WU Long-hua College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

In a Digital Particle Image Velocimetry （DPW） system, the correlation of digital images is normally used to acquire the displacement information of particles and give estimates of the flow field. The accuracy and robustness of the correlation algorithm directly affect the validity of the analysis result. In this article, an improved algorithm for the correlation analysis was proposed which could be used to optimize the selection/determination of the correlation window, analysis area and search path. This algorithm not only reduces largely the amount of calculation, but also improves effectively the accuracy and reliability of the correlation analysis. The algorithm was demonstrated to be accurate and efficient in the measurement of the velocity field in a flocculation pool.

关键词： Digital Particle Image Velocimetry (DPIV),correlation analysis improved algorithm

Forecasting of wind velocity:An improved SVM algorithm combined with simulated annealing

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Journal of Central South University 2013年第2期20卷 451-456页

作者：刘金朋牛东晓张宏运王官庆 School of Economics and Management North China Electric Power University

Accurate forecasting of wind velocity can improve the economic dispatch and safe operation of the power system. Support vector machine (SVM) has been proved to be an efficient approach for forecasting. According to the analysis with support vector machine method, the drawback of determining the parameters only by experts' experience should be improved. After a detailed description of the methodology of SVM and simulated annealing, an improved algorithm was proposed for the automatic optimization of parameters using SVM method. An example has proved that the proposed method can efficiently select the parameters of the SVM method. And by optimizing the parameters, the forecasting accuracy of the max wind velocity increases by 34.45%, which indicates that the new SASVM model improves the forecasting accuracy.

关键词： wind velocity forecasting improved algorithm simulated annealing support vector machine

Reduction of ultrasonic echo noise based on improved wavelet threshold de-noising algorithm for friction welding

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China Welding 2010年第3期19卷 61-65页

作者：尹欣张臻王旻 Department of Mechanical and Electrical Engineering Zhengzhou Institute of Aeronautical Industry Management Zhengzhou450015. Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015. Henan No. 2 Thermal Power Construction Company Zhengzhou 450005.

In the ultrasonic detection of defects in friction welded joints, it is difficult to exactly detect some weak bonding defects because of the noise pollution. This paper proposed an improved threshold function based on the multi-resolution analysis wavelet threshold de-noising method which was put forward by Donoho and Johnstone, and applied this method in the de-noising of the defective signals. This threshold function overcomes the discontinuous shortcoming of the hard-threshold function and the disadvantage of soft threshold function which causes an invariable deviation between the estimated wavelet coeffwients and the decomposed wavelet coefficients. The improved threshold function is of simple expression and convenient for calculation. The actual test results of defect noise signal show that this improved method can get less mean square error （ MSE ） and higher signal-to-noise ratio of reconstructed signals than those calculated from hard threshold and soft threshold methods. The improved threshold function has excellent de-noising effect.

关键词： wavelet threshold friction welding de-noising improved algorithm

An improved Phase Retrieval algorithm for X-ray In-line Phase-Contrast Imaging

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Chinese Journal of Biomedical Engineering(English Edition) 2016年第2期25卷 69-75页

作者： GUO Yun-feng ZHUANG Tian-ge SUN Jian-qi School of Biomedical Engineering and Med-X Research Institute Shanghai Jiao Tong University

Phase contrast imaging technique has been improved promptly in recent years. Among these techniques in-line phase-contrast imaging is widely used. Various algorithms for in-line phase retrieval have been proposed so far such as TIE(transport of intensity equation), CTF(contrast transfer function), first born-approximations, GSF(Gerchberg-Saxton-Fienup), etc. Bronnikov's algorithm(BA) is a type of linear algorithm that is simple and efficient. But it can only be used without absorption situations. In this paper, an improved algorithm based on BA was presented. The approach adds Δφ(x,y) to the phase map φ_b(x,y) retrieved by BA to make the reconstructed phase map more precise. Further, the approach was evaluated on simulated images and confirmed to be accurate at higher absorption rates.

关键词： in-line phase contrast imaging phase retrieval improved algorithm

Fuzzy Evaluation on Food Safety Based on improved Membership Degree Transformation algorithm

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Fuzzy Evaluation on Food Safety Based on Improved Membership...

Application of improved back-propagation algorithms in classification and detection of scars defects on rails surfaces

2010 International Conference on Advanced Measurement and Test (AMT 2010)

作者： Chenghua Shi 1 2 a Yapeng Wang 1 b 1 College of Economics&Management Huazhong Agricultural University P.R.China 430070 2 School of Economics and Management Hebei University of Engineering P.R.China 056038

It needs a scientific and complete index system for a comprehensive evaluation on the safety of foods in some region or some *** the use of advanced evaluation technologies is also an important work of food safety *** paper eliminated the redundant data in index membership for object classification by defining distinguishable weight and extracted valid values to compute object *** improved algorithm of membership degree transformation includes three calculation steps which can be summarized as"effective,comparison and composition",which is denoted as M（1,2,3）.The paper applied the new algorithm in fuzzy evaluation on the safety of *** results show the validity of the improved model and the model can achieve the dynamic evaluation of the safety of foods in some region or some country.

关键词： food safety fuzzy evaluation analytic hierarchy process membership degree transformation improved algorithm

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High Technology Letters 2018年第3期24卷 249-256页

作者：石甜 Kong Jianyi Wang Xingdong Liu Zhao School of Machinery and Automation Wuhan University of Science and Technology

An experimental platform with bracket structures,cables,parallel computer and imaging system is designed for defects detecting on steel rails. Meanwhile,an improved gradient descent algorithm based on a self-adaptive learning rate and a fixed momentum factor is developed to train back-propagation neural network for accurate and efficient defects classifications. Detection results of rolling scar defects show that such detection system can achieve accurate positioning to defects edges for its improved noise suppression. More precise characteristic parameters of defects can also be ***,defects classification is adopted to remedy the limitations of low convergence rate and local minimum. It can also attain the optimal training precision of 0. 00926 with the least 96 iterations. Finally,an enhanced identification rate of 95% has been confirmed for defects by using the detection system. It will also be positive in producing high-quality steel rails and guaranteeing the national transport safety.

关键词： detection platform steel rail improved algorithm defect classification identification rate

COMPUTER PROGRAM FOR DIRECTED STRUCTURE TOPOLOGY OPTIMIZATION

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Acta Mechanica Solida Sinica 2015年第4期28卷 431-440页

作者： Xianjie Wang Xun'an Zhang Kepeng Cheng School of Urban Construction and Management Yunnan University School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University

To compensate for the imperfection of traditional bi-directional evolutionary structural optimization, material interpolation scheme and sensitivity filter functions are introduced. A suitable filter can overcome the checkerboard and mesh-dependency. And the historical information on accurate elemental sensitivity numbers are used to keep the objective function converging steadily. Apart from rational intervals of the relevant important parameters, the concept of distinguishing between active and non-active elements design is proposed, which can be widely used for improving the function and artistry of structures directly, especially for a one whose accurate size is not given. Furthermore, user-friendly software packages are developed to enhance its accessibility for practicing engineers and architects. And to reduce the time cost for large timeconsuming complex structure optimization, parallel computing is built-in in the MATLAB codes. The program is easy to use for engineers who may not be familiar with either FEA or structure optimization. And developers can make a deep research on the algorithm by changing the MATLAB codes. Several classical examples are given to show that the improved BESO method is superior for its handy and utility computer program software.

关键词： bi-directional evolutionary structural optimization (BESO) continuum structurescomputer program development improved algorithm directed structure topology optimizationportion construction design

The Application of improved Fuzzy Comprehensive Evaluation method in Practice Teaching Quality Evaluation System

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International Journal of Technology Management 2013年第8期 60-64页

作者： Hu Yang Su Lin Airport Management College Guangzhou Civil Aviation College Guangzhou 510403 China Computer Science and Engineering Department Guangdong Peizheng College Guangzhou 510830 China

According to the theory of fuzzy mathematics, Fuzzy comprehensive evaluation method of the original algorithm is improved, and reduced the possibility loss of the original evaluation data. The improved algorithm is applied in the practice teaching quality evaluation system, and improved the practice teaching quality evaluation results and the accuracy of visual, and promote the teaching management scientific, standardized and institutionalized. In order to establish incentive mechanism, it can bring a positive role to improve teaching quality.

关键词： Fuzzy comprehensive evaluation improved algorithm Quality of practice teaching Evaluation system

Dynamic Alternative Routing Performance Improvement

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Dynamic Alternative Routing Performance Improvement