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A Preliminary Study on the Use of the linear regression method for Multigroup Cross-Section Interpretation

NUCLEAR SCIENCE AND ENGINEERING 2021年第4期195卷 437-452页

作者： Lu, Cihang Wu, Zeyun Virginia Commonwealth Univ Dept Mech & Nucl Engn Richmond VA 23219 USA

Computational modeling and simulations are widely used for evaluation of the performance and safety features of innovative nuclear reactor designs. Multigroup-based deterministic neutronics codes are often employed in these reactor design calculations because they can provide fast predictions of the neutron flux distribution and other neutronics characteristic parameters. Nevertheless, providing accurate multigroup cross sections for deterministic codes is an onerous job, which makes establishing an exhaustive cross-section library computationally prohibitive. Partly because of these reasons, multigroup neutron cross sections are normally stored only at certainty state points in the data library of these deterministic codes, and linear interpolation methodology is commonly utilized to estimate the cross sections at unknown states. However, the applicability of linear interpolation is limited, and the precision of its results is moderate. In this paper, we discuss a preliminary feasibility study that we performed on providing more precise multigroup cross sections for deterministic neutronics codes by using the linear regression methodology. Compared to the traditional linear interpolation method, the linear regression approach principally showed improved computational efficiency considering the use of more data in the cross-section library, and constructed hypothesis functions for the responses of interest with a higher order of accuracy. In this study, a case study on Lightbridge Corporation's metallic fuel element was carried out to demonstrate the feasibility and advantages of linear regression in multigroup cross-section interpretation. A reference cross-section library was established through calculations conducted with the Monte Carlo neutronic code Serpent. Because of the preliminary nature of this feasibility study, only the macroscopic total cross section is considered. linear interpolation and linear regression were both used to estimate cross sections at

关键词： Reactor physics cross-section interpretation Monte Carlo linear regression method

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Based on a linear regression method to study the fiber diameter of car engine oil filter materials

Based on a linear regression method to study the fiber diame...

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International Conference on Sport, Arts Materials and Management Science (SAMMS 2012)

作者： Feng Jian-yong Zhang Jian-chun Zhang Hua Yang Da-Xiang Donghua Univ Text Inst Shanghai Peoples R China Quartermaster Res Inst Gen Logist Dept PLA Beijing Peoples R China Armored Force Engn Inst Beijing Peoples R China

ISBN: (纸本)9783037854075

With regard to the car engine oil filter materials,it is necessary to possess a certain fiber diameter to achieve a preferable porosity and filtration effect. According to the investigation of commonly used oil filter materials in the market,this thesis is firstly selected ten kinds of various automobile oil filter material and then tested their fiber diameter,the main results have the maximum fiber diameter,the minimum fiber diameter and the average fiber diameter,however,the three results are not certain of the relationship. So through the linear regression method to discuss the quantitative mathematical relationship among them and to estabilish a theoretical calculation formula to compute them.

关键词： linear regression method oil filter material fiber diameter significance regression equation

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Determination of Compositions and Stability Constants of Holmium and Yttrium Complexes with Tribromoarsenazo by linear regression method

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Journal of Rare Earths 1991年第1期9卷 5-9页

作者：魏永巨丁儒乾 Department of Chemistry Hebei Teachers' College Shijiazhuang 050091China

According to the appearing of isosbestic point in the absorption spectra of Ho/Y-Tribromoarsenazo (TBA)systems,the complexation reaction is considered to be M+nL=ML_n.A method has been proposed based on it for calculating the mole fraction of free complexing agent in the solutions from spectral *** two linear regression formula have been introduced to determine the composition,the molar absorptivity,the conditional stability constant of the complex and the concentration of the complexing agent. This method has been used in Ho-TBA and Y-TBA ***^(3+)and Y^(3+)react with TBA and form 1: 2 complexes in HCl-NaAc buffer solution at pH *** molar absorptivities determined are 1.03×10~8 and 1.10×10~8 cm^2·mol^(-1),and the conditional stability constants(logβ_2)are 11.37 and 11.15 *** considering the pH effect in TBA complexing,their stability constants(log β_2^(ahs))are 43.23 and 43.01. *** new method is adaptable to such systems where the accurate concentration of the complexing agent can not be known conveniently.

关键词： Holmium Yttrium Tribromoarsenazo Absorption spectra Stablilty constant linear regression method

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Force model of robot bone grinding based on finite element analysis

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MEASUREMENT 2025年 243卷

作者： Yang, Kai Jia, Qingxuan Feng, Chao Huang, Juxiang Chen, Gang Yang, Zheng Beijing Univ Posts & Telecommun Sch Automat Beijing 100876 Peoples R China Beijing Univ Posts & Telecommun Sch Elect Engn Beijing 100876 Peoples R China Beijing Jishuitan Hosp Guizhou Hosp Natl Reg Med Ctr Guiyang 550014 Guizhou Peoples R China Capital Med Univ Beijing Jishuitan Hosp Natl Ctr Orthopaed Beijing 100035 Peoples R China

Bone grinding represents a formidable challenge during open epiphyseal surgery, as grinding force may result in potential damage to bone and surrounding tissues. To address this issue, this study establishes a correlation between grinding force and bone density, as well as feed rate and rotational speed. Given the limited availability of experimental data on bone grinding, a finite element analysis (FEA) model is developed. Subsequently, the impact of bone density, feed rate and rotational speed on grinding force is determined through linear regression method. The accuracy and sensitivity of the grinding force model are then assessed, revealing a maximum prediction deviation of 4.87%. Finally, based on the established model, safe operating parameters and boundary conditions for robot bone grinding are identified.

关键词： Grinding Bone Force Finite element analysis linear regression method

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Adaptive encoding based lossless data hiding method for VQ compressed images using tabu search

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INFORMATION SCIENCES 2022年 602卷 128-142页

作者： Weng, Shaowei Zhang, Tiancong Wu, Zhijie Lin, Juan Hong, Wien Fujian Univ Technol Fujian Prov Key Lab Big Data Min & Applicat Fuzhou 350108 Peoples R China Fujian Univ Technol Sch Elect Engn & Phys Fuzhou 350108 Peoples R China Guangdong Univ Technol Sch Informat Engn Guangzhou Peoples R China Fujian Polytech Normal Univ Fujian Prov Univ Engn Res Ctr ICH Digitalizat & Multisource Informa Fuzhou 350300 Peoples R China Taichung Univ Sci & Technol Dept Comp Sci & Informat Engn Taichung Taiwan

A novel joint image coding and reversible data hiding method for vector quantization (VQ) compressed images is proposed in this paper. Since the original VQ indices often exhibit uncorrelated, a rearrangement of them by considering their correlations may benefit the prediction performance so as to reduce the required bitrate. In this study, the tabu search algorithm is employed to rearrange codewords by fully exploiting their neighboring correlations, yielding a moepressible rearranged indices. By combining more highly-correlated indices of a to-be-predicted index into prediction, the improved linear regression method is then applied to achieve a sharper prediction-error histogram and less required additional information. After prediction, an adaptive run-length encoding method is presented to encode prediction errors, thereby eliminating unnecessary indicators. Experimental results demonstrate that the proposed method effectively reduces the bitrate of the compressed image while providing a comparable hiding capacity. (c) 2022 Elsevier Inc. All rights reserved.

关键词： Vector quantization Reversible data hiding Index rearrangement Tabu search algorithm linear regression method Vector quantization Reversible data hiding Index rearrangement Tabu search algorithm linear regression method

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Thermal degradation kinetics of vinyl polyperoxide copolymers

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POLYMER DEGRADATION AND STABILITY 2004年第1期84卷 173-179页

作者： Sivalingam, G De, P Karthik, R Madras, G Indian Inst Sci Dept Chem Engn Bangalore 12 Karnataka India

The thermal degradation of various vinyl polyperoxides (poly(styrene peroxide) [PSP], poly(methyl methacrylate peroxide) [PMMAP], poly(a-methyl styrene peroxide) [PAMSP]) and their binary copolyperoxides (PSP-PAMSP [SA], PSP-PMMAP [SM], PAMSP-PMMAP [AM]) were studied in a Thermogravimetric Analyzer (TGA). The thermal stability of the polyperoxides is in the order of PMMAP>SM>AM>SA>PSP>PAMSP. The addition of PAMSP to PSP showed a synergistic effect with higher thermal stability of the copolymer while the addition of PAMSP or PSP to PMMAP did not affect the thermal degradation of the copolymers. A method based on regression was proposed to determine the degradation parameters. The activation energies of degradation for the homopolyperoxides and copolyperoxides were determined by various methods and found in agreement with each other. (C) 2004 Elsevier Ltd. All rights reserved.

关键词： vinyl polyperoxides copolyperoxides activation energies rate coefficients linear regression method thermal degradation

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Bend strength variation of ceramics in serial fabrication

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JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 2014年第7期34卷 1873-1879页

作者： Ambrozic, Milan Gorjan, Lovro Gomilsek, Masa Univ Maribor Fac Nat Sci & Math SLO-2000 Maribor Slovenia Jozef Stefan Inst Ljubljana 1000 Slovenia

We have performed a statistical evaluation of more than 10 000 experimental strength values of test pieces from a serial production of alumina products where in each production series 12 samples were broken. The Weibull parameters were obtained by three different methods: linear regression, maximum-likelihood and moments' method. The methods give different values of parameters even for this large number of data, but all the correlation coefficients are high and similar. Evaluating Weibull parameters for each testing group gives expected systematically different values of particular Weibull modulus as compared to the whole population of collected data. However, when the order of experimental data is mixed, the average Weibull modulus is lower than that corresponding to time ordered data. This difference can be served as an indication for variation of products' quality from series to series. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Bend strength Weibull statistics linear regression method Maximum-likelihood method Moments' method

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Computational aerodynamic modeling for flight dynamics simulation of ram-air parachutes

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AEROSPACE SCIENCE AND TECHNOLOGY 2016年 54卷 286-301页

作者： Ghoreyshi, Mehdi Bergeron, Keith Jirasek, Adam Seidel, Juergen Lofthouse, Andrew J. Cummings, Russell M. US Air Force Acad High Performance Comp Res Ctr Colorado Springs CO 80840 USA US Army Natick Res Ctr Dev & Engn Natick MA 01760 USA

This work presents a step toward bridging the gap between flight dynamics simulation of ram-air parachutes and high-fidelity computational fluid dynamics. Today's parachute design codes mainly rely on the empirical or semi-empirical methods generated from wind tunnel experiments and drop tests. The outcome of this study will hopefully help to reduce the cost of experiments and drop testing in the design of future canopies and to better understand the aerodynamic characteristics of these geometries. In this work, the parachute geometries were modeled as rigid rectangular wings with an aspect ratio of two and zero anhedral angle. The wings have seven opening cells and the trailing edge is deflected or not deflected. To validate computational methods, the aerodynamic predictions of similar wings, but with closed and round inlets, are compared with experimental data available from the Subsonic Wind Tunnel at United States Air Force Academy. Total lift and drag force coefficients were measured at a Reynolds number of 1.4 million. The results show that computational predictions of fine (closed-inlet) grids match the experimental data very well up to the stall angle. Both experiments and simulations show that closed wings have sharp stalling characteristics. The aerodynamics of closed wings up to stall can be approximated by linear functions and their derivatives. The closed wings show a negative static stability with respect to changes in the angle of attack. The open wings, on other hand, have positive static stability in the longitudinal and lateral directions. The open wings exhibit highly nonlinear unsteady aerodynamic characteristics;they also stall earlier and have higher drag values than the closed wings. The aerodynamic derivatives of open and closed wings were estimated using a linear regression method and training data simulated in small-amplitude oscillations in pitch, yaw, and roll directions. While the open wings have large oscillations in aerodynamic coeffic

关键词： Ram-air parachutes linear regression method Dynamic derivatives

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Determination of alcohol content in water alcohol hydrates using near-infrared spectroscopy and segmentation regression model

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TRANSACTIONS OF THE INSTITUTE OF MEASUREMENT AND CONTROL 2011年第5期33卷 479-493页

作者： Jin, X. D. Zhao, Z. M. Zhang, L. Yu, X. L. Nanjing Univ Aeronaut & Astronaut Coll Sci Nanjing 210016 Peoples R China CSIRO Mat Sci & Engn Highett Vic 3190 Australia Nanjing Univ Aeronaut & Astronaut Coll Automat Engn Nanjing 210016 Peoples R China

This paper puts forward a measurement method of alcohol content in the mixture of water and alcohol based on near-infrared spectroscopy and segmentation regression model. The wavelengths, which are 1580, 2081 and 2309 nm, are picked out as three characteristic absorption wavelengths of alcohol, whereas 1206, 1456 and 1936 nm are picked out as three characteristic absorption wavelengths of water. The characteristic absorbance has a linear relationship to the alcohol concentration in the sample according to the principle of Lambert. Multiple linear regression equations 1 and 2 are built respectively based on the characteristic absorbance of alcohol and water, and the alcohol concentration is calculated using these two equations. However, the representative characteristic of overtone and combination absorption will change as the concentration of composing component changes so that the measuring effects of different regression equations, which are built by characteristic absorption values of different component, are different in the measurement of different concentration samples. In order to improve the prediction accuracy, this paper adopts the segmentation regression model equation to calculate the alcohol concentration in the sample, ie, we use equation 2 to calculate the alcohol concentration for the low alcohol content samples and use equation 1 to calculate the alcohol concentration for the samples of alcohol concentration between 50% and 70%;on the other hand, we use the mean calculation of equations 1 and 2 as prediction for the high alcohol concentration samples. The adoption of the regression model equation can reduce the mean prediction error for the samples in different alcohol concentrations without increasing the complexity of the equation. Nevertheless, we need to obtain the approximate value of alcohol concentration first in order to determine the distribution range of alcohol concentration.

关键词： alcohol concentration characteristic absorption wavelength linear regression method near-infrared analysis segmentation regression model

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Convergence and uncertainty analyses in Monte-Carlo based sensitivity analysis

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ENVIRONMENTAL MODELLING & SOFTWARE 2011年第4期26卷 444-457页

作者： Yang, Jing Univ Guelph Dept Geog Guelph ON N1G 2W1 Canada

Sensitivity analysis plays an important role in model development, calibration, uncertainty analysis, scenario analysis, and, hence, decision making. With the availability of different sensitivity analysis techniques, selecting an appropriate technique, monitoring the convergence and estimating the uncertainty of the sensitivity indices are very crucial for environmental modelling, especially for distributed models due to their high non-linearity, non-monotonicity, highly correlated parameters, and intensive computational requirements. It would be useful to identify whether some techniques outperform others with respect to computational requirements, reliability, and other criteria. This paper proposes two methods to monitor the convergence and estimate the uncertainty of sensitivity analysis techniques. One is based on the central limit theorem and the other on the bootstrap technique. These two methods are implemented to assess five different sensitivity analysis techniques applied to an environmental model. These techniques are: the Sobol' method, the Morris method, linear regression (LR), Regionalized Sensitivity Analysis (RSA), and non-parametric smoothing. The results show that: (i) the Sobol' method is very robust in quantifying sensitivities and ranking parameters despite a large number of model evaluations;(ii) the Morris method is efficient to rank out unimportant parameters at a medium cost;(iii) the non-parametric smoothing is reliable and robust in quantifying the main effects and low-order interactions while requiring a small number of model evaluations;finally (iv) the other two techniques, that is, LR and RSA, should be used with care. (C) 2010 Elsevier Ltd. All rights reserved.

关键词： Sensitivity analysis Uncertainty analysis Sobol' method Morris method linear regression method Regionalized sensitivity analysis Non-parametric smoothing

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