Chromatic Confocal Displacement Measurment Based on Correlation Algorithm

2013 ◽  
Vol 446-447 ◽  
pp. 909-914
Author(s):  
Chun Hui Niu ◽  
Yong Lv

Chromatic confocal technique application in displacement measurement is studied theoretically and experimentally. a set of refractive lenses are designed and a measurement system is established. Correlation fitting method is proposed to fit spectrum curve and find peak wavelength. Results with use of correlation fitting method are compared with Gaussian and smoothing spline fitting methods. It indicate that correlation fitting method have higher extracting accuracy of peak wavelength and smaller RMSE of linear fitting due to narrower and smoother correlation curve.

2012 ◽  
Vol 19 (2) ◽  
pp. 381-394
Author(s):  
José Pereira ◽  
Octavian Postolache ◽  
Pedro Girão

Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System PerformanceThis paper presents a voltammetric segmented voltage sweep mode that can be used to identify and measure heavy metals' concentrations. The proposed sweep mode covers a set of voltage ranges that are centered around the redox potentials of the metals that are under analysis. The heavy metal measurement system can take advantage of the historical database of measurements to identify the metals with higher concentrations in a given geographical area, and perform a segmented sweep around predefined voltage ranges or, alternatively, the system can perform a fast linear voltage sweep to identify the voltammetric current peaks and then perform a segmented voltage sweep around the set of voltages that are associated with the voltammetric current peaks. The paper also includes the presentation of two auto-calibration modes that can be used to improve system's reliability and proposes the usage of a Gaussian curve fitting of voltammetric data to identify heavy metals and to evaluate their concentrations. Several simulation and experimental results, that validate the theoretical expectations, are also presented in the paper.


2017 ◽  
Vol 76 (8) ◽  
pp. 2242-2253 ◽  
Author(s):  
Z. Yavari ◽  
M. Noroozifar

In this study, black carbon from pine cone (BCPC) and acidic-modified BCPC (MBCPC) powder as a popular agricultural waste in the southeast of Iran were used for cadmium removal from aqueous solutions. The effect of various factors, such as surface chemistry and dosage of adsorbent, contact time, size of particles, initial concentration of cadmium, temperature, and pH of aqueous solutions, was investigated. The results show cadmium removal with usage of the mentioned adsorbents increased after acidic modification. It was noteworthy in this work that the removal percentage of pollutant was above 90% for suggested biosorbents. The obtained experimental data for optimum conditions were selected to model the adsorption behavior of the materials with usage of six isotherm equations via non-linear fitting method and the residual root mean square error estimation for each model. The adsorption of cadmium preferably fitted Khan and Langmuir–Freundlich isotherms for BCPC and MBCPC adsorbents, respectively. The kinetic studies via linear fitting method proved the second-order kinetic was the applicable model for the adsorption process. Thermodynamic studies show the adsorption process of cadmium onto BCPC and MBCPC was spontaneous and endothermic.


2010 ◽  
Vol 55 (7) ◽  
pp. 2498-2504 ◽  
Author(s):  
Ruijing Jiang ◽  
Changfeng Chen ◽  
Shuqi Zheng

2018 ◽  
Vol 537 (1) ◽  
pp. 79-89
Author(s):  
Dezhi Li ◽  
Bin Zhang ◽  
Benjamin Ducharne ◽  
Linsen Zhu

2014 ◽  
Vol 614 ◽  
pp. 275-278
Author(s):  
Yu Tang ◽  
Xiang Deng ◽  
Shuo Tian

Electrostatic sensor is based on the principle of electrostatic induction. It is widely used for gas/solid two-phase flow measurement because it has the advantages of simple structure, high sensitivity, low cost, etc. In this paper, a velocity measurement system of gas/solid flow based on electrostatic sensor and cross-correlation algorithm is discussed. Electrostatic sensor with circular electrode is adopted. By COMSOL optimum simulation, the axial length of the electrode is designed. The signal conditioning circuits are discussed and cross-correlation algorithm is analyzed. The initial experimental results demonstrate that the velocity measurement system of gas/solid flow designed in this paper is feasible.


2012 ◽  
Vol 629 ◽  
pp. 488-492
Author(s):  
Yan Jiao Zhao ◽  
Yu Xin Wang ◽  
Guo He ◽  
Hong Hua Zhao

A Soil Deformation Measurement System using OPENCV library and FFTW library in C++ was developed in this paper. The system applied camera calibration based on neural network and Fasst Fourier Transform (FFT) cross-correlation algorithm for Particle Image Velocimetry (PIV). It is used to obtain soil deformation data, such as displacements, velocity and strain, and visualize the deformation. Experiments show that this system could acquire deformation data from soil images accurately, efficiently and continuously, which provides a strong proof that image processing technology has practical significance and application value in the research field of geotechnical engineering.


2013 ◽  
Vol 455 ◽  
pp. 486-490
Author(s):  
Lai Jie Wu ◽  
Bin Ma ◽  
Yuan Hong Yang

This paper developed a resistivity measurement system on the platform of in-situ detector which based on seafloor drilling machine. In order to precisely process the weak voltage signal which outputted by the resistivity probe, the paper carried out the cross-correlation algorithm theoretical derivation and MATLAB simulation, then ported the algorithm to TMS320F28069 DSP processor and designed hardware. A mass of contrast experiment shows that the cross-correlation algorithm is an effective method to process weak signal. It can improve accuracy and anti-jamming ability of the submarine sediment resistivity measurement system. The method of submarine sediment resistivity measurement can be widely used in fields of marine geological survey, marine environment research, etc.


2013 ◽  
Vol 816-817 ◽  
pp. 140-143
Author(s):  
Zhi Gang Yu ◽  
Li Na Wang ◽  
Jia Liu

This paper presents a general calculation method of steel hardenability. First use non-linear fitting method to establish a general relationship between hardenability coefficient and end-quench distance, and then use SVM method to establish the relationship between alloying elements and hardenability coefficients. It solves the limited applicability and poor precisions problems of the currently applied calculation methods for hardenability. It gives an enhancement scheme to make sure the accuracy of the model when the data are not complete enough. Experimental data show that using this method can effectively improve the hardenability prediction accuracy and can be widely used.


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