The Centroid Method in Inequalities

Optical interferometry plays an important role in the topographical surface measurement and characterization in precision/ultra-precision manufacturing. An appropriate surface reconstruction algorithm is essential in obtaining accurate topography information from the digitized interferograms. However, the performance of a surface reconstruction algorithm in interferometric measurements is influenced by environmental disturbances and system noise. This paper presents a comparative analysis of three algorithms commonly used for coherence envelope detection in vertical scanning interferometry, including the centroid method, fast Fourier transform (FFT), and Hilbert transform (HT). Numerical analysis and experimental studies were carried out to evaluate the performance of different envelope detection algorithms in terms of measurement accuracy, speed, and noise resistance. Step height standards were measured using a developed interferometer and the step profiles were reconstructed by different algorithms. The results show that the centroid method has a higher measurement speed than the FFT and HT methods, but it can only provide acceptable measurement accuracy at a low noise level. The FFT and HT methods outperform the centroid method in terms of noise immunity and measurement accuracy. Even if the FFT and HT methods provide similar measurement accuracy, the HT method has a superior measurement speed compared to the FFT method.

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Research on laser stripe characteristics and center extraction algorithm for desktop laser scanner

SN Applied Sciences ◽

10.1007/s42452-021-04309-w ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Xiaoquan Shi ◽

Yazhou Sun ◽

Haitao Liu ◽

Linqi Bai ◽

Chonghao Lin

Keyword(s):

Laser Scanner ◽

Bright Spot ◽

Distribution Characteristics ◽

Ambient Light ◽

Centroid Method ◽

Laser Stripe ◽

Wide Range ◽

Laser Scanners ◽

Extraction Algorithm ◽

Large Width

AbstractThis study presents laser stripe center extraction algorithm for desktop-level 3D laser scanners. The laser stripe center extraction accuracy is an important factor affecting 3D scanning result. Desktop-level devices should have adaptability of a wide range of scanning objects. In this paper, laser stripe energy distribution characteristics with different laser stripe width, ambient light, materials and colors are obtained by experiments. Experiment results show that waveforms of bright spot, low brightness stripe and stripe with large width are complex or easily disturbed, so the center extraction algorithm of them are studied. The extraction effects of extremum method, gradient method and gray centroid method under different conditions are compared. Based on traditional grayscale value, a weighted grayscale value is proposed to extract laser stripe center. Standard deviations of extracted pixel position and fitting pixel position are calculated by different method with different weighted grayscale value. For different conditions, especially for different ambient light intensity, weight matrix plays an important role to extraction result.

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Sub-Pixel Coded Structured Light Stripe Boundary Location Using Weighted Centroid Method

2010 International Conference on Biomedical Engineering and Computer Science ◽

10.1109/icbecs.2010.5462302 ◽

2010 ◽

Cited By ~ 1

Author(s):

Yanjun Chen ◽

Kuanquan Wang ◽

Wangmeng Zuo ◽

Qiufeng Wu ◽

Yanjun Chen

Keyword(s):

Structured Light ◽

Centroid Method ◽

Boundary Location

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Ranking Fuzzy Numbers by Centroid Method

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v8n3.134 ◽

2014 ◽

Vol 8 (3) ◽

Author(s):

Fateen Najwa Azman ◽

Lazim Abdullah

Keyword(s):

Numerical Calculation ◽

Decision Process ◽

Fuzzy Numbers ◽

New Method ◽

Centroid Method ◽

Generalized Fuzzy Numbers

Ranking fuzzy numbers are one of the important tools in decision process. There are many methods that have been proposed by a number of researchers but most of the methods are nondiscriminating and counterintuitive. Thus, proposing a new method for ranking fuzzy numbers are very prominent. The main objective of this paper is to get better ranking results to rank generalized fuzzy numbers than existing method. This paper reviews the centroid method in ranking fuzzy numbers by several researchers. A new calculation of centroid method will be proposed in this paper. At the end of the paper, a numerical calculation and a comparison of centroid method between the proposed method and other researchers’ method will be showed to check on its consistency.

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Improving Neural Network Classifier Using Gradient-Based Floating Centroid Method

Communications in Computer and Information Science - Neural Information Processing ◽

10.1007/978-3-030-36802-9_45 ◽

2019 ◽

pp. 423-431

Author(s):

Mazharul Islam ◽

Shuangrong Liu ◽

Xiaojing Zhang ◽

Lin Wang

Keyword(s):

Neural Network ◽

Neural Network Classifier ◽

Centroid Method ◽

Gradient Based

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Robust centroid method

Computational Statistics & Data Analysis ◽

10.1016/j.csda.2006.03.012 ◽

2006 ◽

Vol 51 (2) ◽

pp. 737-746 ◽

Cited By ~ 3

Author(s):

V. Choulakian ◽

J. Allard ◽

J. Almhana

Keyword(s):

Centroid Method

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A Fuzzy EOQ Model for Deteriorating Items With Allowable Shortage and Inspection Under the Trade Credit

Handbook of Research on Promoting Business Process Improvement Through Inventory Control Techniques - Advances in Logistics, Operations, and Management Science ◽

10.4018/978-1-5225-3232-3.ch014 ◽

2018 ◽

pp. 233-249

Author(s):

Chandra K. Jaggi ◽

Bimal Kumar Mishra ◽

T. C. Panda

Keyword(s):

Trade Credit ◽

Method Comparison ◽

Deteriorating Items ◽

Order Quantity ◽

Centroid Method ◽

Deterioration Rate ◽

Eoq Model ◽

Permissible Delay In Payment ◽

Demand Rate ◽

Fuzzy Cost

This chapter develops an economic order quantity model for deteriorating items with initial inspection, allowable shortage under the condition of permissible delay in payment by fuzzify the demand rate, deterioration rate and inspection parameter of non-defective parameter based on as triangular fuzzy numbers to fit the real word. The total fuzzy cost function has been defuzzified using signed distance and centroid method. Comparison between these two methods has also been discussed. The validity of the model has been established with the help of a hypothetical numerical example.

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Predictable Scenarios of Fuzzy Logic Analysis for Sprinkler Irrigation Control

Precision Agriculture Technologies for Food Security and Sustainability - Advances in Environmental Engineering and Green Technologies ◽

10.4018/978-1-7998-5000-7.ch009 ◽

2021 ◽

pp. 210-235

Author(s):

Mohamed Elsayed Elhagarey ◽

Mohamed M. Hushki ◽

Szabo E. Istvan

Keyword(s):

Fuzzy Inference ◽

Irrigation System ◽

Sprinkler Irrigation ◽

Irrigation Performance ◽

Centroid Method ◽

Irrigation Practice ◽

Personal Experiences ◽

Triangular Function ◽

Common Technique ◽

Fuzzy Logic Analysis

MATLAB will be utilized to validate the various irrigation systems and report it; the air temperature, wind, and humidity will be member functions to improve the efficiency of irrigation performance before the irrigation process, and the fuzzy information system consists of fuzzy rules, which are derived from information of experts or from input-output learning of the system. Rules mimic human reasoning. Mamdani method is mostly applied in the fuzzy inference technique, and the generalized bell function is used for both of temperature and wind where the triangular function used for humidity. The principles were based on the last experiments and personal experiences, and the output will change into a crisp value from this procedure of defuzzification. There are many different methods to do defuzzification, but the most common technique is centroid method. The resultant surface graphic is enough to monitor, validate, and report the irrigation system efficiency to execute and schedule the irrigation practice management.

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