Application of High-Linearity Analog Optocoupler in DSP Acquisition Circuit

2012 ◽  
Vol 232 ◽  
pp. 944-948 ◽  
Author(s):  
Ying Qi Tan ◽  
Xiang Yang Liu ◽  
Bao Qing Den
Keyword(s):  
High Accuracy ◽  
Least Square ◽  
Experiment Data ◽  
Good Linearity ◽  
High Linearity ◽  
Analog Signals ◽  
Noisy Signals ◽  
Method Of Least Square ◽  
Proper Design ◽  
Hardware Circuit

An applied hardware circuit for detecting the AGC signals isolated with DSP is designed based on a high-linearity analog optocoupler. The problem of narrow measuring scope, low linearity and instability which caused by noisy signals is resolved when collects industrial analog signals into DSP. The practical circuit with proper design of components is designed through repeated experiments. The experiment data are analyzed by the method of least-square. The analyzed results show this circuit has the high accuracy and good linearity.

Prediction of Comprehensive Thermal Error of a Preloaded Ball Screw on a Gantry Milling Machine

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Kuo Liu ◽  
Haibo Liu ◽  
Te Li ◽  
Yongqing Wang ◽  
Mingjia Sun ◽  
...  
Keyword(s):  
Thermal Field ◽  
Thermal Characteristics ◽  
Thermal Error ◽  
Least Square Method ◽  
High Accuracy ◽  
Least Square ◽  
Ball Screw ◽  
Milling Machine ◽  
Thermal Fields ◽  
Proposed Model

The conception of the comprehensive thermal error of servo axes is given. Thermal characteristics of a preloaded ball screw on a gantry milling machine is investigated, and the error and temperature data are obtained. The comprehensive thermal error is divided into two parts: thermal expansion error ((TEE) in the stroke range) and thermal drift error ((TDE) of origin). The thermal mechanism and thermal error variation of preloaded ball screw are expounded. Based on the generation, conduction, and convection theory of heat, the thermal field models of screw caused by friction of screw-nut pairs and bearing blocks are derived. The prediction for TEE is presented based on thermal fields of multiheat sources. Besides, the factors influencing TDE are analyzed, and the model of TDE is established based on the least square method. The predicted thermal field of the screw is analyzed. The simulation and experimental results indicate that high accuracy stability can be obtained using the proposed model. Moreover, high accuracy stability can still be achieved even if the moving state of servo axis changes randomly, the screw is preloaded, and the thermal deformation process is complex. Strong robustness of the model is verified.

scholarly journals Normal tissue tolerance dose for cervical radiotherapy to the NTCP model using a method of least square fit

2020 ◽  
Vol 12 (1) ◽  
pp. 215-220
Author(s):  
E. Onuh ◽  
A.S. Ajuji ◽  
N. Rabiu ◽  
M.S. Anas ◽  
M. Jada
Keyword(s):  
Normal Tissue ◽  
Normal Tissue Complication Probability ◽  
Least Square ◽  
Planning System ◽  
Radiotherapy Planning ◽  
Treatment Planning System ◽  
Normal Tissue Tolerance ◽  
Tolerance Dose ◽  
Method Of Least Square ◽  
Least Square Fit

The purpose of this study is to evaluate the impact of Normal Tissue Complication Probability (NTCP) models on radiation treatment plans. We estimated NTCP parameters for the organs at risk (OARs) for cervical cancer radiotherapy. We pooled individual patient data from fifty patients who were treated with External Beam Radiotherapy technique between March 2012 and November 2013 in a part of Northern Nigeria with the exclusion of patients who had other gynaecological malignancies. Three basic methods were followed during the radiotherapy planning of these patients which included the pre-planning stage, planning radiotherapy treatment stage and treatment delivery. Various tests were carried out on these patients which helped to confirm the diagnosis after which they were treated using the linear accelerator, computed tomography simulator and the treatment planning system. We calculated the normal tissue tolerance doses for partial volumes of the organs using the values of the above –said parameters for published data on normal tissue tolerance doses. This article shows a graphical representation of the computed NTCP for left femur, right femur and skin presented and a fairly good correspondence is found between the curves for head of femurs and skin. Keywords: Normal Tissue Tolerance Dose, Normal Tissue Complication Probability, Method of Least Square Fit, Cervical Radiotherapy

Strength Reduction Technique for Non-Linear Failure Criterion

2012 ◽  
Vol 446-449 ◽  
pp. 1568-1572
Author(s):  
Li Ren ◽  
Ting Ai ◽  
Zhe Ming Zhu ◽  
Ling Zhi Xie ◽  
Ru Zhang
Keyword(s):  
Power Function ◽  
Shear Failure ◽  
Least Square ◽  
Failure Envelope ◽  
Collocation Points ◽  
Strength Reduction Technique ◽  
Non Linear ◽  
Linear Shear ◽  
Method Of Least Square ◽  
As Stress

In the analysis of slope stability, a reduction method of non-linear shear strength was applied. A power function was used to approximate the shear failure envelope which is determined by the non-linear criterion or experimental data, and then the coefficients of that function were determined by using the collocation points. The equivalent friction angles and cohesive strengths of rock as well as stress range were determined by fitting an average linear relationship to the approximate curve generated by the power function through the method of least square. Finally, an example was presented to demonstrate the superiority and feasibility of the method introduced in this paper.

A Recursive Gradient Method of Least Square Support Vector Machine and its Application

2013 ◽  
Vol 339 ◽  
pp. 349-354
Author(s):  
Xiang Yong Luo ◽  
Wei Min Lv ◽  
Zhao Qing Song ◽  
Shi Wei Jiang
Keyword(s):  
Support Vector Machine ◽  
Parameter Estimation ◽  
Gradient Method ◽  
Least Square ◽  
Support Vector ◽  
Recursive Method ◽  
Online Identification ◽  
Method Of Least Square ◽  
Bad Data

Least Square Support Vector Machine (LS-SVM) is an important machine of Support Vector Machine (SVM). But this method can not be used for online identification, and maybe lead to calculation inflation. A gradient recursive method of LS-SVM is presented by combining the LS-SVM method with the gradient method. This method can overcome the influence of bad data to the parameter estimation, has a stronger robustness, and improves the calculation speed of LS-SVM. The presented method is applied to the modeling of chaotic series. The simulation example validates the validity of the presented method.

A Method of High Accuracy Control for Motor-Based Photoelectric Tracking Instrumentation Base on Inclinometer

2013 ◽  
Vol 423-426 ◽  
pp. 2846-2850
Author(s):  
Da Yong Ning ◽  
Chang Le Sun ◽  
Yong Jun Gong
Keyword(s):  
System Change ◽  
Vertical Axis ◽  
High Accuracy ◽  
Horizontal Axis ◽  
Cad Model ◽  
Accuracy Control ◽  
Digital Signals ◽  
Controlled System ◽  
Technology Analysis ◽  
Analog Signals

A mathematic method of ensuring motor-based photoelectric tracking instrumentation work high accurately was introduced, the SCA100T inclinometer was settled under the base, and examine plane of base real-timely. The inclinometer output analog signals and transmit it to AT89C51 through A/D converters, and AT89C51 output digital signals and transmit it to PC through RS-232. The PC convert signals of inclinometer into angle values of horizontal axis and vertical axis and transmit the values to main controlled system of photoelectric tracking instrumentation, the controlled system change the angles of horizontal axis and vertical axis. The CAD model was built and simulated with virtual prototype technology .Analysis and simulation proved that the mathematic method could keep tracking precision of motor-based photoelectric tracking instrumentation.

An Improved Device of Detecting True and False Coin

2012 ◽  
Vol 503-504 ◽  
pp. 1589-1592
Author(s):  
Chun He Yu ◽  
Xiao Feng Tian ◽  
Dan Ping Zhang
Keyword(s):  
Low Frequency ◽  
Detection Algorithm ◽  
Least Square ◽  
External Control ◽  
Testing Technology ◽  
Method Of Least Square ◽  
Processing Module ◽  
Distinct Frequency ◽  
Control Circuits ◽  
Signal Processing Module

In order to reduce the loss of an automatic coin machine for using a 1-Yuan false coin, an improved device is designed by applying the eddy current nondestructive testing technology, which uses two distinct frequency signals to detect the information of coin. The device includes four modules: two LC oscillating circuits, signal processing module, microprocessor module and external control circuits. The detection algorithm selects two counting values under two distinct frequency signals. The low frequency circuit detects the information of the coin material, and the high frequency circuit detects the feature of the coin surface. The detection region of true coin is decided by the method of least square. The experiment shows that the device has the characters of stability, reliability and high accuracy.

The Circle-End-Face Centering Device Based on Image Processing

2014 ◽  
Vol 926-930 ◽  
pp. 3447-3450
Author(s):  
Yong Bo Li ◽  
Yun Zhao Xu ◽  
Jia He
Keyword(s):  
Image Processing ◽  
Digital Image Processing ◽  
High Stability ◽  
Least Square Method ◽  
High Accuracy ◽  
Concentric Circle ◽  
Least Square ◽  
Programmable Logic ◽  
Edge Extraction ◽  
Stability And Accuracy

The circle-end-face centering device which is in the base of image processing accomplishes the center of the cylinders end face by digital image processing. Through edge extraction and doing the matching in the calculation of the least square method, the coordinate of the central of the circle can be calculated. At last, the drill will be moved to the central of the circle and do the punching by the actuator. This equipment is in the high accuracy and speed compared with the traditional way and the concentric circle laser of marking with the center. Meanwhile, the actuator consists of the programmable logic controller, touch panel and servo drivers which is in the high stability and accuracy. Certainly it is easy to be controlled by the method.

Study on the Configuration Effect of a Vortex Finder for a Gas-Solid Cyclone Separator Using Eulerian-Eulerian Approach

2013 ◽  
Author(s):  
Moonho Choi ◽  
Sungwon Lee ◽  
Jin-Ki Ham
Keyword(s):  
Pressure Loss ◽  
Erosion Rate ◽  
Separation Efficiency ◽  
Solid Particles ◽  
Least Square ◽  
Design Parameters ◽  
Reduced Pressure ◽  
Eulerian Approach ◽  
Method Of Least Square ◽  
Vortex Finder

Granular model, a part of Eulerian-Eulerian approach is implemented to improve a gas-solid cyclone separator’s performances which are largely determined by dimensions of a vortex finder. Design-Of-Experiments method analyzes the performances such as pressure loss, separation efficiency, and erosion rate of each variation model due to the change of design parameters of the vortex finder. Separation efficiencies due to the motion of solid particles are predicted according to the classical efficiency model by using the method of least square. The numerical results are validated by comparing with previously reported experimental data. The standard Stairmand design cyclone is improved judging from the reduced pressure loss by 43%, the reduced cut size by 63% and the reduced erosion rate by 2% by changing the position and the diameter of the vortex finder.

Study on Data Fusion Algorithms of Hot-Pressing Measurement Process of Wood-Based Panels

2015 ◽  
Vol 740 ◽  
pp. 547-552
Author(s):  
Hai Ying Yu ◽  
Jun Hua ◽  
Xiu Li Zhou ◽  
Jiu Yang Hou
Keyword(s):  
Hot Pressing ◽  
Weight Coefficient ◽  
High Accuracy ◽  
Least Square ◽  
Sensor Technology ◽  
Complex Mechanism ◽  
Pressure Data ◽  
Temperature And Pressure ◽  
Measurement Variance ◽  
And Performance

Measurement error often exists during hot pressing of the wood-based panels due to the complex mechanism of the process, technological conditions, environment noises and performance of the sensors. Multi-sensor technology is used for mat temperature and pressure data processing to improve the precision and reliability of data. By determining the information weight coefficient with the corresponding measurement variance of each sensor the weighted least square algorithm is applied to achieve high accuracy of overall estimation. The precision of overall estimation value is preferable than the partial estimation of each sensor. A target recognition frame of control strategy is set, and D-S evidence combination principles and reasoning theory are introduced to select the object of greatest credibility for decision making. The results of experiment demonstrate the effectiveness and reliability of the algorithm.

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