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Noether-Mei Symmetry of Mechanical System in Phase Space

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Communications in Theoretical Physics 2006年第5期45卷 882-884页

作者： FANG Jian-hui wang peng DING Ning College of Physical Science and Technology China University of Petroleum Dongying 257061 China

In this paper, a new kind of symmetry and its conserved quantities of a mechanical system in phase space are studied. The definition of this new symmetry, i,e., a Noether-Mei symmetry, is presented, and the criterion of this symmetry is also given. The Noether conserved quantity and the Mei conserved quantity deduced from the Noether-Mei symmetry of the system are obtained. Finally, two examples are given to illustrate the Bpplication of the results.

关键词： Noether-Mei symmetry conserved quantity mechanical system phase space

Perturbation and Adiabatic Invariants of Mei Symmetry for Nonholonomic Mechanical Systems

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Communications in Theoretical Physics 2007年第4期47卷 594-596页

作者： DING Ning FANG Jian-hui wang peng College of Physical Science and Technology China University of Petroleum Dongying 257061 China

Based on the concept of adiabatic invariant, the perturbation and adiabatic invariants of the Mei symmetry for nonholonomic mechanical systems are studied. The exact invariants of the Mei symmetry for the system without perturbation are given. The perturbation to the Mei symmetry is discussed and the adiabatic invariants of the Mei symmetry for the perturbed system are obtained.

关键词： Mei symmetry perturbation adiabatic invariant nonholonomic mechanical system

Non-Noether Conserved Quantity of Poincaré-Chetaev Equations of a Generalized Classical Mechanics

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Communications in Theoretical Physics 2006年第6期45卷 961-964页

作者： ZHANG peng-Yu FANG Jian-hui wang peng DING Ning College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In the present paper the Lie symmetrical non-Noether conserved quantity of the Poincaré Chetaev equations of a generalized classical mechanics under the general infinitesimal transformations of Lie groups is discussed. First, we establish the determining equations of Lie symmetry of the equations. Second, the Lie symmetrical non-Noether conserved quantity of the equations is deduced. Finally, an example is given to illustrate the application of the results.

关键词： Poincaré-Chetaev equations generalized classical mechanics Lie symmetry non-Noether conserved quantity

Artifacts in two-dimensional shear wave elastography of liver

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World Journal of Gastroenterology 2023年第21期29卷 3318-3327页

作者： hui-peng wang peng-Chao Zheng Xue-Mei wang Liang Sang Department of Ultrasound The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

BACKGROUND Artifacts are common when using two-dimensional shear wave elastography(2-D SWE)to measure liver stiffness(LS),but they are poorly *** To investigate the presence and influence of artifacts in 2-D SWE of *** We included 158 patients with chronic liver disease,who underwent 2-D SWE examination by a novice and an expert.A cross line at the center of the elastogram was drawn and was divided it into four locations:top-left,top-right,bottom-left,and *** occurrence frequency of artifacts in different locations was *** influence of artifacts on the LS measurements was evaluated by comparing the elastogram with the most artifacts(EMA)and the elastogram with the least artifacts(ELA).RESULTS The percentage of elastograms with artifacts in the novice(51.7%)was significantly higher than that of the expert(19.6%)(P<0.001).It was found that both operators had the highest frequency of artifacts at bottom-left,followed by top-left and bottom-right,and top-right had the lowest *** LS values(LSVs)and standard deviation values of EMAs were significantly higher than those of ELAs for both *** intraclass correlation coefficient value of 0.96 was found in the LSVs of EMAs of the two operators,and it increased to 0.98 when the LSVs of the ELAs were *** operators had lower stability index values for EMAs than ELAs,but the difference was only statistically significant for the *** Artifacts are common when using 2-D SWE to measure LS,especially for the *** may lead to the overestimation of LS and reduce the repeatability and reliability of LS measurements.

关键词： Ultrasound Elastography Artifact Liver

Perturbation to Lie Symmetry and Lutzky Adiabatic Invariants for Lagrange Systems

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Communications in Theoretical Physics 2008年第1期49卷 57-60页

作者： DING Ning FANG Jian-hui wang peng ZHANG Xiao-Ni College of Physics Science and Technology China University of Petroleum Dongying 2570617 China

Based on the concept of adiabatic invariant, perturbation to Lie symmetry and Lutzky adiabatic invariants for Lagrange systems are studied by using different methods from those of previous works. Exact invariants induced from Lie symmetry of the system without perturbation are given. Perturbation to Lie symmetry is discussed and Lutzky adiabatic invariants of the system subject to perturbation are obtained.

关键词： symmetry perturbation Lutzky adiabatic invariant Lagrange system

A New Type of Conserved Quantity of Mei Symmetry for Lagrange Systems

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Communications in Theoretical Physics 2007年第5X期48卷 799-800页

作者： DING Ning FANG Jian-hui wang peng ZHANG Xiao-Ni College of Physics Science and Technology China University of Petroleum Dongying 257061 China

A new type of conserved quantity, which is induced from the Mei symmetry of Lagrange systems, is studied. The conditions for that the new type of conserved quantity exists and the form of the new type of conserved quantity are obtained. An illustrated example is given. The Noether conserved quantity induced from the Mei symmetry of Lagrange systems is a special case of the new type of conserved quantity given in this paper.

关键词： Mei symmetry new type of conserved quantity Lagrange system

Noether-Lie Symmetry of Generalized Classical Mechanical Systems

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Communications in Theoretical Physics 2008年第2期49卷 305-307页

作者： ZHANG Xiao-Ni FANG Jian-hui wang peng DING Ning College of Physics Science and Technology China University of Petroleum Dongying 257061. China

In this paper, the Noether Lie symmetry and conserved quantities of generalized classical mechanical system are studied. The definition and the criterion of the Noether Lie symmetry for the system under the general infinitesimal transformations of groups are given. The Noether conserved quantity and the Hojman conserved quantity deduced from the Noether Lie symmetry are obtained. An example is given to illustrate the application of the results.

关键词： generalized classical mechanical system Noether-Lie symmetry Noether conserved quantity Hojman conserved quantity

Evaluation of specific fecal protein biochips for the diagnosis of colorectal cancer

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World Journal of Gastroenterology 2014年第5期20卷 1332-1339页

作者： hui-peng wang Yang-Yun wang Jie Pan Rong Cen Yuan-Kun Cai Department of General Surgery The 5thPeople’s Hospital of Shanghai Fudan University Department of endoscopy Shanghai Shuguang Hospital Shanghai University of Traditional Chinese Medicine

AIM: To develop and initially test a potential fecal protein biochip for the screening of colorectal cancer (CRC).

关键词： Protein biochip Feces Colorectal cancer Fibroblast growth factor-23 Thrombopoietin

Essentially normal Hilbert modules and K-homology Ⅲ:Homogenous quotient modules of Hardy modules on the bidisk

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Science China Mathematics 2007年第3期50卷 387-411页

作者： Kun-yu GUO & peng-hui wang School of Mathematics, Pudan University, Shanghai 200433, China School of Mathematics Fudan University Shanghai 200433 China

In this paper, we study the homogenous quotient modules of the Hardy module on the bidisk. The essential normality of the homogenous quotient modules is completely characterized. We also describe the essential spectrum for a general quotient module. The paper also considers K-homology invariant defined in the case of the homogenous quotient modules on the bidisk.

关键词： Hardy modules bidisk essential normality K-homology.