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Establishment of normal operating zone models by boundary points for CSTR-DC-recycle chemical processes
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作者 Poku Gyasi Jiandong Wang +1 位作者 Mengyao Wei Hao Jing 《Chinese Journal of Chemical Engineering》 2025年第9期140-157,共18页
Integrated continuous stirred-tank reactors and distillation columns with recycle(CSTR-DC-recycle)are essential components in chemical processes.This paper proposes a method to establish a normal operating zone(NOZ)mo... Integrated continuous stirred-tank reactors and distillation columns with recycle(CSTR-DC-recycle)are essential components in chemical processes.This paper proposes a method to establish a normal operating zone(NOZ)model to represent allowable variations of the CSTR-DC-recycle chemical processes.The NOZ is a geometric space containing all safe operating points of the CSTR-DC-recycle chemical processes,so that it is an effective model for process monitoring.The novelty of the proposed method is to establish the NOZ model based on boundary points.The boundary points make it possible to capture the actual geometric space irrespective of the space shape.In contrast,existing methods represent the NOZ of processes by fixed mathematical models such as ellipsoidal and convex-hull models;they are not suitable for the CSTR-DC-recycle chemical processes whose NOZs cannot be exactly defined by fixed mathematical structures.Simulated case studies based on Aspen Hysys software are given to illustrate the proposed method. 展开更多
关键词 Chemical processes Grey-box model normal operating zone Bayesian estimation Model uncertainty measurement Boundary points
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Effect of normalizing cooling process on microstructure and precipitates in low-temperature silicon steel 被引量:14
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作者 李慧 冯运莉 +2 位作者 宋孟 梁精龙 苍大强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期770-776,共7页
Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared wi... Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared with the hot-rolled plate by optical microscopy (OM), transmission electron microscopy (TEM), and energy dispersive spectrometry (EDS). The results show that, the surface microstructure is uniform, the proportion of recrystallization in matrix increases, and the banding textures are narrowed; the precipitates, whose quantity in normalized plate is more than that in hot-rolled plate greatly, are mainly A1N, MnS, composite precipitates (Cu,Mn)S and so on. Normalizing technology with a temperature of 1120 ℃, holding for 3 min, and a two-stage cooling is a most advantaged method to obtain oriented silicon steel with sharper Goss texture and higher magnetic properties, owing to the uniform surface microstructures and the obvious inhomogeneity of microstructures along the thickness. The normalizing technology with the two-stage cooling is the optimum process, which can generate more fine precipitates dispersed over the matrix, and be beneficial for finished products to get higher magnetic properties. 展开更多
关键词 low temperature grain-oriented silicon steel normalizing cooling process MICROSTRUCTURE PRECIPITATE magnetic property
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Average Run Length in TEWMA Control Charts:Analytical Solutions for AR(p)Processes and Real Data Applications
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作者 Sirawit Makaew Yupaporn Areepong Saowanit Sukparungsee 《Computer Modeling in Engineering & Sciences》 2025年第5期1617-1634,共18页
This study aims to examine the explicit solution for calculating the Average Run Length(ARL)on the triple exponentially weighted moving average(TEWMA)control chart applied to autoregressive model(AR(p)),where AR(p)is ... This study aims to examine the explicit solution for calculating the Average Run Length(ARL)on the triple exponentially weighted moving average(TEWMA)control chart applied to autoregressive model(AR(p)),where AR(p)is an autoregressive model of order p,representing a time series with dependencies on its p previous values.Additionally,the study evaluates the accuracy of both explicit and numerical integral equation(NIE)solutions for AR(p)using the TEWMA control chart,focusing on the absolute percentage relative error.The results indicate that the explicit and approximate solutions are in close agreement.Furthermore,the study investigates the performance of exponentially weighted moving average(EWMA)and TEWMA control charts in detecting changes in the process,using the relative mean index(RMI)as a measure.The findings demonstrate that the TEWMA control chart outperforms the EWMA control chart in detecting process changes,especially when the value ofλis sufficiently large.In addition,an analysis using historical data from the SET index between January 2024 and May 2024 and historical data of global annual plastic production,the results of both data sets also emphasize the superior performance of the TEWMA control chart. 展开更多
关键词 EWMA control chart TEWMA control charts average run length shift detection explicit formula Fredholm integral equation Banach’s fixed-point theorem ar(p)process
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Process Capability Analysis of Delivering Neonatal Care with Normal Weight (Case Study of Neonatal Weight Data at a Maternity Clinic in Banjarmasin)
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作者 Dewi Anggraini 《Journal of Life Sciences》 2011年第12期996-1002,共7页
Statistical Quality Control (SQC) is used to analyze and monitor quality characteristic measurements of normal neonatal weight in a maternity clinic in Banjarmasin in this paper. The objective of this study is to as... Statistical Quality Control (SQC) is used to analyze and monitor quality characteristic measurements of normal neonatal weight in a maternity clinic in Banjarmasin in this paper. The objective of this study is to assist medical practitioners in observing pregnant women to deliver their babies with normal weight. It is also assumed that pregnant women who delivered their babies in the clinic have been monitored during their nine-month pregnancy. Thus, they can manage their own pregnancy to deliver normal weight babies. The use of Statistical Process Control (SPC) tools, such as frequency histogram, probability plot, and the implementation of Shewhart, R, and S control charts as primary techniques, are presented to display the monitoring aspects of the process. In addition, Process Capability Analysis (PCA) is performed to ensure that the process outcomes are capable of meeting certain requirements or specifications. The Process Capability Ratio (PCR) for the process is also presented. This analysis is an essential part of an overall quality improvement program. 展开更多
关键词 process capability analysis Shewhart control chart R-chart normal neonatal weight.
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Well-posedness and exponential stability of a dynamic frictionless contact problem with normal compliance and infinite memory
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作者 Imane Ouakil Benyattou Benabderrahmane Yamna Boukhatem 《Applied Mathematics(A Journal of Chinese Universities)》 2026年第1期99-119,共21页
A model for dynamic frictionless contact between a viscoelastic body and foundation is considered.The viscoelastic constitutive law is assumed to be nonlinear and the contact is modelled with the normal compliance con... A model for dynamic frictionless contact between a viscoelastic body and foundation is considered.The viscoelastic constitutive law is assumed to be nonlinear and the contact is modelled with the normal compliance condition.We obtain the well-posedness using nonlinear semigroup theory arguments.Moreover,the exponential stability result of the solution is shown by using the energy method to produce a suitable Lyapunov function. 展开更多
关键词 dynamic process viscoelastic body normal compliance nonlinear semigroup theory exponential stability
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Joint asymptotic distributions of maximas for multi-variate normal process
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作者 Peng Zuoxiang(Department of Mathematics, Southwest China Normal University, Chongqing 630715) 《西南师范大学学报(自然科学版)》 CAS CSCD 1995年第4期361-368,共8页
Jointasymptoticdistributionsofmaximasofmulti-variatenormalprocessPengZuoxiang(DepartmentofMathematics,Southw... Jointasymptoticdistributionsofmaximasofmulti-variatenormalprocessPengZuoxiang(DepartmentofMathematics,SouthwestChinaNormalUni... 展开更多
关键词 多维正态过程 最大值 联合渐近分布
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Evaluation of Two Absolute Radiometric Normalization Algorithms for Pre-processing of Landsat Imagery 被引量:13
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作者 徐涵秋 《Journal of China University of Geosciences》 SCIE CSCD 2006年第2期146-150,157,共6页
In order to evaluate radiometric normalization techniques, two image normalization algorithms for absolute radiometric correction of Landsat imagery were quantitatively compared in this paper, which are the Illuminati... In order to evaluate radiometric normalization techniques, two image normalization algorithms for absolute radiometric correction of Landsat imagery were quantitatively compared in this paper, which are the Illumination Correction Model proposed by Markham and Irish and the Illumination and Atmospheric Correction Model developed by the Remote Sensing and GIS Laboratory of the Utah State University. Relative noise, correlation coefficient and slope value were used as the criteria for the evaluation and comparison, which were derived from pseudo-invarlant features identified from multitemporal Landsat image pairs of Xiamen (厦门) and Fuzhou (福州) areas, both located in the eastern Fujian (福建) Province of China. Compared with the unnormalized image, the radiometric differences between the normalized multitemporal images were significantly reduced when the seasons of multitemporal images were different. However, there was no significant difference between the normalized and unnorrealized images with a similar seasonal condition. Furthermore, the correction results of two algorithms are similar when the images are relatively clear with a uniform atmospheric condition. Therefore, the radiometric normalization procedures should be carried out if the multitemporal images have a significant seasonal difference. 展开更多
关键词 LANDSAT radiometrie correction data normalization pseudo-invariant features image processing.
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From Nonparametric Density Estimation to Parametric Estimation of Multidimensional Diffusion Processes 被引量:1
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作者 Julien Apala N’drin Ouagnina Hili 《Applied Mathematics》 2015年第9期1592-1610,共19页
The paper deals with the estimation of parameters of multidimensional diffusion processes that are discretely observed. We construct estimator of the parameters based on the minimum Hellinger distance method. This met... The paper deals with the estimation of parameters of multidimensional diffusion processes that are discretely observed. We construct estimator of the parameters based on the minimum Hellinger distance method. This method is based on the minimization of the Hellinger distance between the density of the invariant distribution of the diffusion process and a nonparametric estimator of this density. We give conditions which ensure the existence of an invariant measure that admits density with respect to the Lebesgue measure and the strong mixing property with exponential rate for the Markov process. Under this condition, we define an estimator of the density based on kernel function and study his properties (almost sure convergence and asymptotic normality). After, using the estimator of the density, we construct the minimum Hellinger distance estimator of the parameters of the diffusion process and establish the almost sure convergence and the asymptotic normality of this estimator. To illustrate the properties of the estimator of the parameters, we apply the method to two examples of multidimensional diffusion processes. 展开更多
关键词 Hellinger Distance Estimation MULTIDIMENSIONAL Diffusion processes STRONG MIXING process CONSISTENCE ASYMPTOTIC normalITY
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CARRIER FREQUENCY OFFSET ESTIMATION FOR INTERLEAVED OFDMA UPLINK BASED ON SUBSPACE PROCESSING 被引量:1
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作者 Fan Da Cao Zhigang 《Journal of Electronics(China)》 2007年第4期433-438,共6页
This paper investigates Carrier Frequency Offset (CFO) estimation in the uplink of the Orthogonal Frequency-Division Multiple Access (OFDMA) systems with the interleaved subcarrier assignment. CFOs between the transmi... This paper investigates Carrier Frequency Offset (CFO) estimation in the uplink of the Orthogonal Frequency-Division Multiple Access (OFDMA) systems with the interleaved subcarrier assignment. CFOs between the transmitters and the uplink receiver will destroy orthogonality among different subcarriers, hence resulting in inter-carrier interference and multiuser interference. A two-stage frequency offset estimation algorithm based on subspace processing is proposed. The main advantage of the proposed method is that it can obtain the CFOs of all users simultaneously using only one OFDMA block. Compared with the previously known methods, it not only has a relatively low implementation complexity but is also suitable for random subchannel assignment. 展开更多
关键词 Orthogonal Frequency-Division Multiple Access (OFDMA) Carrier Frequency Offset (CFO) Subspace processing normalized Root Mean Square Error (NRMSE)
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A note on self-normalized Dickey-Fuller test for unit root in autoregressive time series with GARCH errors 被引量:1
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作者 YANG Xiao-rong ZHANG Li-xin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期197-201,共5页
In this article, the unit root test for AR(p) model with GARCH errors is considered. The Dickey-Fuller test statistics are rewritten in the form of self-normalized sums, and the asymptotic distribution of the test s... In this article, the unit root test for AR(p) model with GARCH errors is considered. The Dickey-Fuller test statistics are rewritten in the form of self-normalized sums, and the asymptotic distribution of the test statistics is derived under the weak conditions. 展开更多
关键词 unit root ar (p)-GarCH (1 1) SELF-normalIZED Dickey-Fuller test statistic.
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VR、AR技术在服装领域的研究热点及发展脉络 被引量:3
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作者 李雪珂 姚远 《丝绸》 北大核心 2025年第3期43-56,共14页
随着虚拟现实和增强现实技术的迅猛发展,其在服装领域的应用日益显著。本文借助文献计量软件CiteSpace梳理AR/VR技术在国内外服装领域的研究热点、发展脉络、前沿和趋势。研究结果表明,AR和VR技术在国内服装领域的研究热点主要集中在基... 随着虚拟现实和增强现实技术的迅猛发展,其在服装领域的应用日益显著。本文借助文献计量软件CiteSpace梳理AR/VR技术在国内外服装领域的研究热点、发展脉络、前沿和趋势。研究结果表明,AR和VR技术在国内服装领域的研究热点主要集中在基础理论与内涵、虚拟服装的展示与应用,以及历史服饰文化遗产数字化复原等方面。国外该领域的研究更多关注深度学习与系统架构、计算机与图像处理技术的升级。未来,集成新兴技术和智能化应用,推动服装行业可持续发展和数智化转型将是中国服装领域的发展方向。 展开更多
关键词 虚拟服装 VR技术 ar技术 研究热点 知识图谱 发展脉络 智能时尚
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A RESEARCH ON SEGMENTATION OF NONSTATIONARY STOCHASTIC PROCESS INTO PIECEWISE STATIONARY STOCHASTIC PROCESS
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作者 Wang Wenhua Wang Hongyu(Department of Electronic Engineering, Dalian University of Technology, Dalian 116023) 《Journal of Electronics(China)》 1997年第4期304-310,共7页
P. M. Djuric, etc.(1992) researched on the segmentation of nonstationary stochastic process into piecewise stationary stochastic process by Bayesian criterion ,and gave a dynamic equation about the number of segments,... P. M. Djuric, etc.(1992) researched on the segmentation of nonstationary stochastic process into piecewise stationary stochastic process by Bayesian criterion ,and gave a dynamic equation about the number of segments, their boundaries and AR model orders for each segment, but did not give detailed solution for the equation. Because the solution for the equation is very complex, this paper investigates the solution, derives some recursive relations, simplifies the problem ,saves computation time and goes further into the segmentation of nonstationary stochastic process into piecewise stationary stochastic process. 展开更多
关键词 STOCHASTIC process STATIONarY STOCHASTIC process ar models RECURSIVE relation
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Preparation and Properties of TiN_x-SiO_2 Antireflective Coatings with Print Process
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作者 姚丽峰 丁益民 郭景康 《Journal of Shanghai University(English Edition)》 CAS 2005年第1期82-85,共4页
This paper describes the preparation and properties of TiN_x-SiO_2 double-layered antireflective(AR) coatings that were applied with print process. The coating material was analyzed and TiN_x was used instead of TiO_2... This paper describes the preparation and properties of TiN_x-SiO_2 double-layered antireflective(AR) coatings that were applied with print process. The coating material was analyzed and TiN_x was used instead of TiO_2 as high refractive material. The influence of solution concentration on AR property was studied. The testing result shows that the coatings using print process are featured with excellent mechanical property and the AR property is comparable to American Southwall AR product. It is expected that the study would promote the industrialization progress in AR coatings. 展开更多
关键词 TiN_x print process ar coatings.
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A weak invariance principle for self-normalized products of sums of mixing sequences
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作者 FU Ke-ang HUANG Wei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期183-189,共7页
Let variables in the {X, Xn, n ≥ 1} be a sequence of strictly stationary φ-mixing positive random domain of attraction of the normal law. Under some suitable conditions the principle for self-normalized products of ... Let variables in the {X, Xn, n ≥ 1} be a sequence of strictly stationary φ-mixing positive random domain of attraction of the normal law. Under some suitable conditions the principle for self-normalized products of partial sums is obtained. 展开更多
关键词 SELF-normalIZED product domain of attraction of the normal law Φ-MIXING Wiener process.
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Some Applications of Higher Moments of the Linear Gaussian White Noise Process
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作者 I. S. Iwueze C. O. Arimie +1 位作者 H. C. Iwu E. Onyemachi 《Applied Mathematics》 2017年第12期1918-1938,共21页
The Linear Gaussian white noise process is an independent and identically distributed (iid) sequence with zero mean and finite variance with distribution N (0, σ2 ) . Hence, if X1, x2, …, Xn is a realization of such... The Linear Gaussian white noise process is an independent and identically distributed (iid) sequence with zero mean and finite variance with distribution N (0, σ2 ) . Hence, if X1, x2, …, Xn is a realization of such an iid sequence, this paper studies in detail the covariance structure of X1d, X2d, …, Xnd, d=1, 2, …. By this study, it is shown that: 1) all powers of a Linear Gaussian White Noise Process are iid but, not normally distributed and 2) the higher moments (variance and kurtosis) of Xtd, d=2, 3, … can be used to distinguish between the Linear Gaussian white noise process and other processes with similar covariance structure. 展开更多
关键词 Stochastic process LINEar Gaussian WHITE Noise process COVarIANCE Structure Stationarity TEST for WHITE Noise process TEST for normalITY
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A real time processing system of seismic waves using personal computers-Function and characteristics
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作者 范军 陈天长 +4 位作者 韩渭宾 曾健 长谷川昭 堀内茂木 郑斯华 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第3期106-110,共5页
Seismological Bureau of Sichuan Province, Chengdu 610041, China2) Center for Analysis and Prediction, State Seismological Bureau, Beijing 100036, China3) Observation Center for Prediction of Earthquakes and Volcanic E... Seismological Bureau of Sichuan Province, Chengdu 610041, China2) Center for Analysis and Prediction, State Seismological Bureau, Beijing 100036, China3) Observation Center for Prediction of Earthquakes and Volcanic Eruptions, Faculty of Sciences, Tohoku University, Sendai 98077, Japan 展开更多
关键词 seismic wave real time processing realtime waveform display ar model the Akaike′s information criteria (AIC)
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Research of the Adaptive Beamformer Based on the Frequency Energy Normalization 被引量:1
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作者 马启明 王宣银 杜栓平 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第1期29-35,共7页
An algorithm of broadband minimum variance distortionless response(MVDR) based on the frequency energy normalization is proposed.First,every narrowband frequency component of the broadband signal is normalized by the ... An algorithm of broadband minimum variance distortionless response(MVDR) based on the frequency energy normalization is proposed.First,every narrowband frequency component of the broadband signal is normalized by the total narrowband energy of all array elements,and the narrowband power is calculated by MVDR.Finally,final spatial energy spectrum can be obtained by averaging or summing all results of every narrowband frequency bin.Any prior-information about the noise or the signal is unnecessary for the proposed method in this paper.The processing gain of the proposed method compared to the conventional broadband MVDR can be obtained as long as the amplitude fluctuation of the array noise frequency spectrum is severer than that of the target signal.The validity of the method is validated by the optimal signal detection theory.Simulation and real data are used to validate the performance of the method.Analysis results show that about 4 dB processing gain compared to the general broadband MVDR can be reached by the proposed method. 展开更多
关键词 自适应波束形成器 正常化 频率 能量 最小方差无畸变响应 宽带信号 MVDR 噪声频谱
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On the Use of Second and Third Moments for the Comparison of Linear Gaussian and Simple Bilinear White Noise Processes
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作者 Christopher Onyema Arimie Iheanyi Sylvester Iwueze +1 位作者 Maxwell Azubuike Ijomah Elechi Onyemachi 《Open Journal of Statistics》 2018年第3期562-583,共22页
The linear Gaussian white noise process (LGWNP) is an independent and identically distributed (iid) sequence with zero mean and finite variance with distribution . Some processes, such as the simple bilinear white noi... The linear Gaussian white noise process (LGWNP) is an independent and identically distributed (iid) sequence with zero mean and finite variance with distribution . Some processes, such as the simple bilinear white noise process (SBWNP), have the same covariance structure like the LGWNP. How can these two processes be distinguished and/or compared? If is a realization of the SBWNP. This paper studies in detail the covariance structure of . It is shown from this study that;1) the covariance structure of is non-normal with distribution equivalent to the linear ARMA(2, 1) model;2) the covariance structure of is iid;3) the variance of can be used for comparison of SBWNP and LGWNP. 展开更多
关键词 White Noise process normalITY Stationarity INVERTIBILITY COVarIANCE Structure
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Symmetry Violation of Time Reversal in Third Order Vertex Angle Renormalization Process of Electromagnetic Interaction
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作者 Xiaochun Mei 《Journal of Modern Physics》 2012年第1期43-47,共5页
According to the current understanding, electromagnetic interaction is invariable under time reversal. However, the proof of time reversal symmetry in quantum theory of field has not considered the effects of high ord... According to the current understanding, electromagnetic interaction is invariable under time reversal. However, the proof of time reversal symmetry in quantum theory of field has not considered the effects of high order perturbation normalizations. It is proved in the paper that when the renormalization effect of third order vertex angles process is taken into account, the symmetry of time reversal will be violated in electromagnetic interaction process. Because the magnitude order of symmetry violation is about 10–5, but the precision of current experiments on time reversal in particle physics is about 10–3, this kind of symmetry violation can not be found. The result reveals the micro-origin of asymmetry of time reversal and can be used to solve the famous irreversibility paradox in the evolution processes of macro- material systems. 展开更多
关键词 Quantum Theory of Field SYMMETRY Time Reversal T VIOLATIONS normalization Vertex Angle process
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Empirical Likelihood Statistical Inference for Compound Poisson Vector Processes under Infinite Covariance Matrix
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作者 程从华 《Journal of Donghua University(English Edition)》 CAS 2023年第1期122-126,共5页
The paper discusses the statistical inference problem of the compound Poisson vector process(CPVP)in the domain of attraction of normal law but with infinite covariance matrix.The empirical likelihood(EL)method to con... The paper discusses the statistical inference problem of the compound Poisson vector process(CPVP)in the domain of attraction of normal law but with infinite covariance matrix.The empirical likelihood(EL)method to construct confidence regions for the mean vector has been proposed.It is a generalization from the finite second-order moments to the infinite second-order moments in the domain of attraction of normal law.The log-empirical likelihood ratio statistic for the average number of the CPVP converges to F distribution in distribution when the population is in the domain of attraction of normal law but has infinite covariance matrix.Some simulation results are proposed to illustrate the method of the paper. 展开更多
关键词 compound Poisson vector process(CPVP) infinite covariance matrix domain of attraction of normal law empirical likelihood(EL)
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