scholarly journals A high order derivation method for distribution network transient data

2021 ◽  
Vol 243 ◽  
pp. 01004
Author(s):  
Bo Xiao ◽  
Li Lv ◽  
Yuxuan Kang ◽  
Qingyu Xie ◽  
Xinyang Wang
Keyword(s):  
Distribution Network ◽  
Least Square Method ◽  
Distribution Networks ◽  
High Order ◽  
Least Square ◽  
Polynomial Fitting ◽  
Base Function ◽  
High Order Derivative ◽  
Order Derivation ◽  
Low Order

Nowadays, high-order data needs to be processed quickly and accurately by various algorithms in distribution networks. It is difficult to ensure the accuracy of calculation both in low-order and high-order cases, due to the theoretical limitations of traditional high-order derivation methods. Aimed to improve the calculation accuracy, a new high-order derivative method based on the polynomial fitting is proposed in this paper. By analyzing the transient characteristics of voltage and current signals in the distribution network, the base fitting-function can be selected, and the coefficient of the base function can be obtained to fit the objective function by the least square method. The original discrete data will be replaced by new fitting-function for derivative operation, which not only ensures the anti-interference ability, but also overcomes the limitations of the traditional polynomial fitting method in high-order cases. The simulation results show that this method has high accuracy in high-order and low-order cases, and has good accuracy and anti-interference ability.

Polynomial Moving Fitting Method for Edge Identification

2011 ◽  
Vol 308-310 ◽  
pp. 2560-2564 ◽  
Author(s):  
Xiang Rong Yuan
Keyword(s):  
Edge Detection ◽  
Curve Fitting ◽  
Polynomial Function ◽  
High Order ◽  
Polynomial Fitting ◽  
Fitting Method ◽  
Order Polynomial ◽  
Better Than ◽  
Low Order

A moving fitting method for edge detection is proposed in this work. Polynomial function is used for the curve fitting of the column of pixels near the edge. Proposed method is compared with polynomial fitting method without sub-segment. The comparison shows that even with low order polynomial, the effects of moving fitting are significantly better than that with high order polynomial fitting without sub-segment.

Numerical Analysis on Concrete Elastic-Plastic Constitutive under Different Restraints

2011 ◽  
Vol 374-377 ◽  
pp. 2442-2445
Author(s):  
Hong Wang ◽  
Chong Jin ◽  
Hong Yuan ◽  
Xiao Zhou Xia
Keyword(s):  
Nonlinear Function ◽  
Least Square Method ◽  
Least Square ◽  
Virtual Experiment ◽  
Nonlinear Method ◽  
Base Function ◽  
Concrete Material ◽  
Oblique Section ◽  
Orthogonal Base ◽  
Convex Deformation

The fitting curve given by least square method is applied in numerical analyzing. The results from semi-unrestrained and completely restricted modeling show convex deformation and damage on oblique section clearly. Advanced virtual experiment illustrates the differences between loading with displacement and pressure, due to the phenomenon that pressing by force will cause deformation on top surface but displacing load wouldn’t. The fitting idea by orthogonal base function will provide a widely road for studying the constitute law of concrete material. Otherwise, the progress of solving nonlinear function is discussed for designing new numerical analyzing tool, and the frame of programming based on nonlinear method is obtained

A high precision indoor positioning method based on UKF

2021 ◽  
pp. 1-14
Author(s):  
Mujie Zhao ◽  
Tao Zhang ◽  
Di Wang
Keyword(s):  
Kalman Filter ◽  
Nonlinear Filtering ◽  
Unscented Kalman Filter ◽  
Least Square Method ◽  
Wide Band ◽  
High Order ◽  
Least Square ◽  
Time Of Arrival ◽  
State Variables ◽  
Fifth Order

Aiming at the nonlinear filter problem in Ultra Wide Band (UWB) navigation and position, a high-order Unscented Kalman Filter (UKF) position method is proposed. On the one hand, the position and velocity are used as state variables to establish a nonlinear filtering model based on UWB position system. On the other hand, based on the fifth order cubature transform (CT), the analytical solution of the high-order unscented Kalman filter is obtained by introducing a free parameter δ. To verify the effectiveness of the proposed method, the Time of Arrival (TOA) location method, the least square method and fifth order CKF method are introduced as comparison methods. The simulation and experimental results show that the proposed high-order UKF method has good positioning accuracy in both static and dynamic UWB positioning methods.

Study on Useful Concrete Elastic-Plastic Constitutive Model

2011 ◽  
Vol 117-119 ◽  
pp. 351-355
Author(s):  
Hong Wang ◽  
Chong Jin ◽  
Hong Yuan ◽  
Xiao Zhou Xia
Keyword(s):  
Orthogonal Polynomial ◽  
Least Square Method ◽  
Least Square ◽  
Plastic Behavior ◽  
Base Function ◽  
Constitutive Function ◽  
Elastic Plastic ◽  
Uniform Function ◽  
Curve Fitting Method ◽  
Convex Deformation

In order to simulate the elastic-plastic behavior of concrete better, an effective curve fitting method is employed to find the constitutive function based on Legendre orthogonal polynomial and least square method. And a new numerical analysis program using arch-length method to deal with nonlinear problem is designed. The most important consequence is that not only the fitting function, but also its derivative function and its definite integral are recursive. The fitting curve given by new method is applied in numerical analyzing. Cube model is examined under uniaxial compressing with completely restricted boundary conditions. The results show convex deformation and the damage on oblique section clearly. Compared with those piecewise fitting functions, the Legendre orthogonal polynomial fitting function obtained can be introduced into the nonlinear harden-soften character of concrete constitute law more convenient because of its uniform function form and continuous derived feature. And the fitting idea by orthogonal base function will provide a widely road for studying the constitute law of concrete material.

Direct Assessment of Effective Renal Plasma Flow from Renoscintigraphy with a Gamma Camera and an On-Line Computer

1981 ◽  
Vol 20 (06) ◽  
pp. 274-278
Author(s):  
J. Liniecki ◽  
J. Bialobrzeski ◽  
Ewa Mlodkowska ◽  
M. J. Surma
Keyword(s):  
Count Rate ◽  
Renal Plasma Flow ◽  
Early Period ◽  
Least Square Method ◽  
Least Square ◽  
Uptake Coefficient ◽  
Positive Linear Correlation ◽  
On Line ◽  
Best Fit ◽  
Plasma Activity

A concept of a kidney uptake coefficient (UC) of 131I-o-hippurate was developed by analogy from the corresponding kidney clearance of blood plasma in the early period after injection of the hippurate. The UC for each kidney was defined as the count-rate over its ROI at a time shorter than the peak in the renoscintigraphic curve divided by the integral of the count-rate curve over the "blood"-ROI. A procedure for normalization of both curves against each other was also developed. The total kidney clearance of the hippurate was determined from the function of plasma activity concentration vs. time after a single injection; the determinations were made at 5, 10, 15, 20, 30, 45, 60, 75 and 90 min after intravenous administration of 131I-o-hippurate and the best-fit curve was obtained by means of the least-square method. When the UC was related to the absolute value of the clearance a positive linear correlation was found (r = 0.922, ρ > 0.99). Using this regression equation the clearance could be estimated in reverse from the uptake coefficient calculated solely on the basis of the renoscintigraphic curves without blood sampling. The errors of the estimate are compatible with the requirement of a fast appraisal of renal function for purposes of clinical diagknosis.

PENGARUH KNOWLEDGE MANAGEMENT, KOMPETENSI, MOTIVASI TERHADAP KINERJA KARYAWAN

2015 ◽  
Vol 5 (2) ◽  
pp. 1
Author(s):  
Miftahol Arifin
Keyword(s):  
Knowledge Management ◽  
Linear Regression ◽  
Significant Influence ◽  
Employee Performance ◽  
Least Square Method ◽  
Least Square ◽  
Analysis Tool ◽  
Ordinary Least Square ◽  
Competence Motivation ◽  
Performance Analyze

The purpose of this research is to analyze the influence of knowledge management on employee performance, analyze the effect of competence on employee performance, analyze the influence of motivation on employee performance). In this study, samples taken are structural employees PT.centris Kingdom Taxi Yogyakarta. The analysis tool in this study using multiple linear regression with Ordinary Least Square method (OLS). The conclusion of this study showed that the variables of knowledge management has a significant influence on employee performance, competence variables have an influence on employee performance, motivation variables have an influence on employee performance, The analysis showed that the variables of knowledge management, competence, motivation on employee performance.Keywords: knowledge management, competence, motivation, employee performance.

Peristaltic Carreau-Yasuda nanofluid flow and mixed heat transfer analysis in an asymmetric vertical and tapered wavy wall channel

2020 ◽  
Vol 1 (1) ◽  
pp. 128-140 ◽  
Author(s):  
Mohammad Hatami ◽  
◽  
D Jing ◽  
Keyword(s):  
Heat Transfer ◽  
Least Square Method ◽  
Weissenberg Number ◽  
Least Square ◽  
Heat Transfer Analysis ◽  
Phase Method ◽  
Nanofluid Flow ◽  
Two Phase ◽  
Nanoparticles Concentration ◽  
The Right

In this study, two-phase asymmetric peristaltic Carreau-Yasuda nanofluid flow in a vertical and tapered wavy channel is demonstrated and the mixed heat transfer analysis is considered for it. For the modeling, two-phase method is considered to be able to study the nanoparticles concentration as a separate phase. Also it is assumed that peristaltic waves travel along X-axis at a constant speed, c. Furthermore, constant temperatures and constant nanoparticle concentrations are considered for both, left and right walls. This study aims at an analytical solution of the problem by means of least square method (LSM) using the Maple 15.0 mathematical software. Numerical outcomes will be compared. Finally, the effects of most important parameters (Weissenberg number, Prandtl number, Brownian motion parameter, thermophoresis parameter, local temperature and nanoparticle Grashof numbers) on the velocities, temperature and nanoparticles concentration functions are presented. As an important outcome, on the left side of the channel, increasing the Grashof numbers leads to a reduction in velocity profiles, while on the right side, it is the other way around.

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