Sensitivity analysis for the weighting factor in the least-square method for the PWR on-line power-distribution monitoring

2017 ◽  
Vol 109 ◽  
pp. 675-683 ◽  
Author(s):  
Zhuo Li ◽  
Liangzhi Cao ◽  
Hongchun Wu ◽  
Wei Shen
Keyword(s):  
Sensitivity Analysis ◽  
Power Distribution ◽  
Least Square Method ◽  
Weighting Factor ◽  
Least Square ◽  
On Line

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.

Thermal investigations of microelectronic chip with non‐uniform power distribution: temperature prediction and thermal placement design optimization

2004 ◽  
Vol 21 (3) ◽  
pp. 29-43 ◽  
Author(s):  
Teck Joo Goh ◽  
K.N. Seetharamu ◽  
G.A. Quadir ◽  
Z.A. Zainal ◽  
K. Jeevan Ganeshamoorthy
Keyword(s):  
Power Distribution ◽  
Heat Dissipation ◽  
Thermal Analyses ◽  
Convection Heat Transfer ◽  
Multiple Linear Regression Model ◽  
Least Square Method ◽  
Least Square ◽  
Junction Temperature ◽  
Thermal Investigations ◽  
Placement Distance

This paper presents the thermal analyses carried out to predict the temperature distribution of the silicon chip with non‐uniform power dissipation patterns and to determine the optimal locations of power generating sources in silicon chip design layout that leads to the desired junction temperature, Tj. Key thermal parameters investigated are the heat source placement distance, level of heat dissipation, and magnitude of convection heat transfer coefficient. Finite element method (FEM) is used to investigate the effect of the key parameters. From the FEM results, a multiple linear regression model employing the least‐square method is developed that relates all three parameters into a single correlation which would predict the maximum junction temperature, Tj,max.

scholarly journals Structural Dynamic Modification Based on Combined Approximations Method

2021 ◽  
Vol 252 ◽  
pp. 03032
Author(s):  
Yuchen Jin ◽  
Xiaochen Yang ◽  
Rui Feng ◽  
Wenjie Zuo ◽  
Guikai Guo
Keyword(s):  
Sensitivity Analysis ◽  
Taylor Series Expansion ◽  
Least Square Method ◽  
Least Square ◽  
Structural Dynamic ◽  
Dynamic Design ◽  
Structural Dynamic Modification ◽  
Dynamic Modification ◽  
Combined Approximations Method ◽  
Combined Approximations

Structural dynamic modification plays an important role in structural dynamic design. This paper presents an algorithm for dynamic modification of the structure, which is based on the Combined Approximations (CA) approach, sensitivity analysis, Taylor series expansion and the least square method. The feasibility of the algorithm is verified by a numerical example and the results show that the algorithm is accurate enough and easy to be implemented.

Research on the EDM Equipment and the Machining Technology of the Precision Micro-Hole

2014 ◽  
Vol 551 ◽  
pp. 237-243
Author(s):  
Yan Hua Cai ◽  
Jian Yong Liu ◽  
Lian Tong Ding ◽  
Shi Shan He ◽  
Shi Fu Zhang
Keyword(s):  
Functional Relation ◽  
Least Square Method ◽  
Least Square ◽  
Work Piece ◽  
Test Results ◽  
Main Structure ◽  
Micro Holes ◽  
Milling Method ◽  
Micro Hole ◽  
On Line

The main structure and key components of the precision EDM equipment are analyzed and researched in this paper. Key components such as main structure, A-axis, W-axis and R-axis are designed. Aimed to machine several kinds of diameters on a work piece, an on-line electrode milling method is studied. And then test this method on an EDM machine. Based on the test results, the functional relation between diameters and the wears of the electrode is confirmed by the least square method. According to this function, the efficiency of the EDM machining for the precision micro-holes is improved.

Methods of Feature Weighting Calculation and Case Retrieval in CBR Case Base

2014 ◽  
Vol 490-491 ◽  
pp. 1391-1398
Author(s):  
Xiao Ping Li
Keyword(s):  
Least Squares Method ◽  
Least Square Method ◽  
High Accuracy ◽  
Typical Case ◽  
Feature Weighting ◽  
Least Square ◽  
Case Retrieval ◽  
Use Of Data ◽  
On Line ◽  
Simulation Results

This article proposes the necessity and feasibility of the use of Data Mining and Knowledge Discovery in CBR reasoning. This paper focuses on the method of empowering feature items based on least squares method parameter identification, and achieve the method of Similarity case retrieval on this basis, the object is the typical case database of railway rescue. The simulation results show that: the least square method can effectively make estimation and identification of the feature parameters, and can continuously correct on-line. High accuracy and fast convergence characteristics of the assigned parameters show that the algorithm has a certain application value.

On-Line Parameter Identification of an Induction Motor With Closed-Loop Speed Control Using the Least Square Method

2017 ◽  
Vol 139 (7) ◽  
Author(s):  
Rafael de Farias Campos ◽  
Eduardo Couto ◽  
Jose de Oliveira ◽  
Ademir Nied
Keyword(s):  
Control System ◽  
Induction Motor ◽  
Least Squares Method ◽  
Least Square Method ◽  
Parametric Identification ◽  
Least Square ◽  
Electrical Parameters ◽  
On Line ◽  
Single Matrix ◽  
Vector Control System

The control system of induction motors is designed to achieve dynamic stability, allowing accurate tracking of flux and speed. However, changes in electrical parameters, due to temperature rise or saturation level, can lead to undesirable errors of speed and position, eventually resulting in instability. This paper presents two modes for parametric identification of the induction motor based on the least squares method: batch estimator and recursive estimator. The objective is to update the electrical parameters during operation when the motor is driven by a vector control system. A drawback related to the batch estimator is the need for high quantity of available memory to make the process of identification robust enough. The proposed algorithm allows the batch estimator to be viewed as a single matrix problem reducing the need for processing memory. The identification procedure is based on the stator currents measurement and stator fluxes estimation. Basically, both modes of identification will be analyzed. Experimental results are presented to demonstrate the theoretical approach.

Study of the On-Line Monitoring on the Effect of Laser Shock Processing for Residual Stress by the Properties of Acoustic Wave

2010 ◽  
Vol 44-47 ◽  
pp. 680-687
Author(s):  
Yang Li ◽  
Hai Yong Qin
Keyword(s):  
Residual Stress ◽  
Acoustic Wave ◽  
Acoustic Waves ◽  
Least Square Method ◽  
Correlation Equation ◽  
Least Square ◽  
Laser Shock ◽  
Laser Shock Processing ◽  
On Line ◽  
Shock Processing

In order to realize the on-line monitoring of the effect of laser shock processing(LSP),acoustic waves generated during the LSP of 45 steel are measured in real time by a wide-band microphone and digitized at a sampling frequency of 48KHz.The waveforms of the received acoustic signal imported to MATLAB are analyzed and in order to investigate the frequency characteristic of the acoustic wave, a power spectral density(PSD) analysis has been carried out. Based on the value of the largest peak of the PSD and compressive residual stress of metal materials induced by the laser shock processing, the correlation equation was established with the application of least square method for the on-line monitoring.

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