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Acta Mechanica Solida Sinica 2024年第3期37卷 371-384页

作者： xia-Hui pan School of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China

Within the context of Gurtin-Murdoch surface elasticity theory,closed-form analytical solutions are derived for an isotropic elastic half-plane subjected to a concentrated/uniform surface *** the effects of residual surface stress and surface elasticity are *** stress function method and Fourier integral transform technique are *** solutions are provided in a compact manner that can easily reduce to special situations that take into account either one surface effect or none at *** results indicate that surface effects generally lower the stress levels and smooth the deformation profiles in the *** elasticity plays a dominant role in the in-plane elastic fields for a tangentially loaded half-plane,while the effect of residual surface stress is fundamentally crucial for the out-of-plane stress and displacement when the half-plane is normally *** the remaining situations,combined effects of surface elasticity and residual surface stress should be *** results for a concentrated surface force serve essentially as fundamental solutions of the Flamant and the half-plane Cerruti problems with surface *** solutions presented in this work may be helpful for understanding the contact behaviors between solids at the nanoscale.

关键词： Surface effects Residual surface stress Surface elasticity Half-plane Analytical solutions

General variational solution for seismic and static active earth pressure on rigid walls considering soil tensile strength cut-off

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第5期24卷 432-449页

作者： Shiguo xiaO Yuan QI pan xia Key Laboratory of High-Speed Railway Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 60031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Department of Geological Engineering Southwest Jiaotong UniversityChengdu 610031China

According to the limit equilibrium state of soils behind rigid walls and the pseudo-static approach,a general closed-form solution to seismic and static active earth pressure on the walls,which considers shear and tension failure of the retained soil,is put forward using a variational calculus *** application point of the active resultant force specified in the proposed method is explained with a clear physical meaning related to possible movement modes of the *** respect of the derived nine dependent equations reflecting the functional characteristics of the earth pressure,the proposed method can be performed easily via an implicit *** are 13 basic factors related to the retained soils,walls,and external loads to be involved in the proposed *** tension crack segment of the slip surface is obviously influenced by these parameters,apart from vertical seismic coefficient and geometric bounds of the surcharge,but the shear slip segment maintains an approximately planar shape almost uninfluenced by these ***,the proposed method quantitatively reflects that the resultant of the active earth pressure is always within a limited range under different possible movements of the same wall.

关键词： Active earth pressure Tensile strength cut-off Variational calculus method Pseudo-static method Strip surcharge

Construction of Solutions and L^1-error Estimates of Viscous Methods for Scalar Conservation Laws with Boundary

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Acta Mathematica Sinica,English Series 2007年第3期23卷 393-410页

作者： Hong xia LIU Tao pan Department of Mathematics Jinan University Guangzhou 510632 P. R. China

This paper is concerned with an initial boundary value problem for strictly convex conservation laws whose weak entropy solution is in the piecewise smooth solution class consisting of finitely many discontinuities. By the structure of the weak entropy solution of the corresponding initial value problem and the boundary entropy condition developed by Bardos-Leroux Nedelec, we give a construction method to the weak entropy solution of the initial boundary value problem. Compared with the initial value problem, the weak entropy solution of the initial boundary value problem includes the following new interaction type： an expansion wave collides with the boundary and the boundary reflects a new shock wave which is tangent to the boundary. According to the structure and some global estimates of the weak entropy solution, we derive the global L^1-error estimate for viscous methods to this initial boundary value problem by using the matching travelling wave solutions method. If the inviscid solution includes the interaction that an expansion wave collides with the boundary and the boundary reflects a new shock wave which is tangent to the boundary, or the inviscid solution includes some shock wave which is tangent to the boundary, then the error of the viscosity solution to the inviscid solution is bounded by O（ε^1/2） in L^1-norm; otherwise, as in the initial value problem, the L^1-error bound is O（ε｜ In ε｜）.

关键词： scalar conservation laws initial boundary value problem global weak entropy solution,error estimate of viscous methods

Uniform and Semi-uniform Convergence for Discontinuous Skew-product Transformation and Observation

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Acta Mathematica Sinica,English Series 2021年第2期37卷 333-344页

作者： xia pan Zuo Huan ZHENG Zhe ZHOU College of Liberal Arts and Sciences National University of Defense TechnologyChangsha 410073P.R.China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190P.R.China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China ollege of Mathematics and Statistics Hainan Normal UniversityHaikou 571158P.R.China

In this paper, for a discontinuous skew-product transformation with the integrable observation function, we obtain uniform ergodic theorem and semi-uniform ergodic theorem. The main assumptions are that discontinuity sets of transformation and observation function are ignorable in some measure-theoretical sense. The theorems extend the classical results which have been established for continuous transformations and continuous observation functions.

关键词： Skew-product transformation uniform ergodicity semi-uniform ergodicity

Dynamic simulation and optimal control strategy for a parallel hybrid hydraulic excavator

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 624-632页

作者： xiao LIN Shuang-xia pan Dong-yun WAN State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The primary focus of this study is to investigate the control strategies of a hybrid system used in hydraulic excavators. First, the structure and evaluation target of hybrid hydraulic excavators are analyzed. Then the dynamic system model including batteries, motor and engine is built as the simulation environment to obtain control results. A so-called multi-work-point dynamic control strategy, which has both closed-loop speed PI (proportion integral) control and direct torque control, is proposed and studied in the simulation model. Simulation results indicate that the hybrid system with this strategy can meet the power demand and achieve better system stability and higher fuel efficiency.

关键词： Hybrid system Hydraulic excavator Multi-work-point dynamic control Direct torque control

Puerarin ameliorates allodynia and hyperalgesia in rats with peripheral nerve injury

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Neural Regeneration Research 2018年第7期13卷 1263-1268页

作者： Heng-Tao Xie Zhong-Yuan xia xia pan Bo Zhao Zhi-Gang Liu Department of Anesthesiology Renmin Hospital of Wuhan University

Puerarin is a major active ingredient of the traditional Chinese plant medicine,Radix Puerariae,and commonly used in the treatment of myocardial and cerebral ***,the effects of puerarin on neuropathic pain are still *** this study,a neuropathic pain animal model was created by partial sciatic nerve ***（30 or 60 mg/kg） was intraperitoneally injected once a day for 7 *** allodynia and thermal hyperalgesia were examined at 1 day after model *** threshold and paw withdrawal latency markedly increased in a dose-dependent manner in puerarin-treated rats,especially at 7 days after model *** 7 days after model establishment,quantitative real-time reverse transcriptase-polymerase chain reaction results showed that puerarin administration reversed m RNA expression of transient receptor potential vanilloid 1（Trpv1） and transient receptor potential ankyrin 1（Trpa1） in a dose-dependent manner in dorsal root ganglion neurons after peripheral nerve *** results suggest that puerarin dose-dependently ameliorates neuropathic pain by suppressing Trpv1 and Trpa1 up-regulation in dorsal root ganglion of neuropathic pain rats.

关键词： nerve regeneration puerarin Radix Puerariae traditional Chinese medicine Trpv1 Trpa1 dorsal root ganglion peripheral nerve injury neuropathic pain mechanical allodynia thermal hyperalgesia neural regeneration

Mechanisms for non-ideal flow in low-power arc-heated supersonic nozzles

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Acta Mechanica Sinica 2015年第4期31卷 500-511页

作者： Cheng-Kang Wu Wen-xia pan xian Meng Hai-Xing Wang State Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences School of Astronautics Beijing University of Aeronautics and Astronautics

The flow in a low-powered arc gas heater com- bined with a supersonic nozzle of throat diameter less than 1 mm is quite complicated and difficult to describe in quan- titative detail. Experiments on arc-heated supersonic jet thrusters of monatomic gases argon and helium have been carried out and their performance measured. The flow charac- teristics are analyzed with the help of numerical simulation. Results show that the viscous effect is the most important factor causing the large difference between ideal and real performance. A large outer section of the exit flow is slow- moving. This is especially pronounced in helium, where 70 % of the exit area of the nozzle might be in subsonic flow. Fric- tion forces can be much larger than the net thrust, reaching several times higher in helium, resulting in very low efficien- cies. Other factors causing the differences between ideal and real flow include： complex flow in the throat region, electric arc extending to the nozzle expansion section, heat transfer to the inlet gas and from the hot plasma, and environmen- tal pressure in the vacuum chamber. It is recognized that the ordinary concepts of supersonic nozzle flow must be greatly modified when dealing with such complicated situations. The general concepts presented in this paper could be helpful in guiding the design and operation of this equipment.

关键词： Arc-heated supersonic jet Low-power Real flow Viscosity effect Low Reynolds number

Traversing the singularity hypersurface by applying the input disturbances to 6-SPS parallel manipulator

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1539-1551页

作者： Yu-tong LI Yu-xin WANG Shuang-xia pan Rui-qin GUO College of Mechanical Engineering and Energy Zhejiang University Hangzhou 310027 China Department of Mechanical Engineering Tongji University Shanghai 200092 China

The singular points of a 6-SPS Stewart platform are distributed on the multi-dimensional singularity hypersurface in the task-space, which divides the workspace of the manipulator into several singularity-free regions. Because of the motion un- certainty at singular points, while the manipulator traverses this kind of hypersurface from one singularity-free region to another, its motion cannot be predetermined. In this paper, a detailed approach for the manipulator to traverse the singularity hypersurface with its non-persistent configuration is presented. First, the singular point transfer disturbance and the pose disturbance, which make the perturbed singular point transfer horizontally and vertically, respectively, are constructed. Through applying these disturbances into the input parameters within the maximum loss control domain, the perturbed persistent configuration is transformed into its corresponding non-persistent one. Under the action of the disturbances, the manipulator can traverse the singularity hypersurface from one singularity-flee region to another with a desired configuration.

关键词： Parallel manipulator Singularity hypersurface Singularity-free moving region

Correlation between TAMs and proliferation and invasion of type endometrial carcinoma

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Asian Pacific Journal of Tropical Medicine 2015年第8期8卷 632-638页

作者： Hong-Lin Hu Han-Song Bai Hai-xia pan Department of Oncology Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital Graduate School Zunyi Medical College

Objective: To explore the correlation between tumor-associated macrophages and the proliferation and invasion of type endometrial carcinoma. Methods: Immunohistochemistry was used to investigate the infiltration of macrophages in normal and different types of hyperplastic endometrial lesions. The proliferation and invasion ability of type endometrial carcinoma cell line RL95-2 influenced by mononuclear macrophage cell line THP-1(constructed M2 type macrophages) was detected by CCK8 and transwell technologies respectively. Transwell was used to evaluate the recruiting ability of RL95-2 on THP-1 cells. Otherwise, the western blot was also used to detect the expression of Cyclin D1 and MMP-2 in RL95-2 with the influence of THP-1. Results: Immunohistochemistry result showed a positive correlation between the number of infiltrating macrophages and the progression of endometrial ***-1 recruited by RL95-2 could promote its proliferation and invasion and enhance the expression of the Cyclin D1 and MMP-2 protein in a time dependent manner(P<0.05). Conclusions: Increase of the number of infiltrating macrophages and its contribution to the tumor inflammatory microenvironment may result in the development of the type endometrial carcinoma.

关键词： Tumor-associated macrophages Type endometrial carcinoma Proliferation Invasion

Controlling multiple optomechanically induced transparency in the distant cavity-optomechanical system

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Chinese Physics B 2021年第3期30卷 314-319页

作者： Rui-Jie xiao Gui-xia pan xiao-Ming Xiu College of Physical Science and Technology Bohai UniversityJinzhou 121013China School of Science Anhui University of Science and TechnologyHuainan 232001China

We theoretically investigate a two-cavity optomechanical system in which each optical cavity couples to a mechanical resonator via radiation pressure force,and the two optical cavities couple to each other via a distant *** study shows that the multiple optomechanically induced transparency can be observed from the output field at the probe *** number and width of the transparent windows can be tuned by the classical driving power *** also analyze the distance of the two outermost transparency windows,which shows a linear relation with the parameters Pl andλ.Our approach is feasible for controlling multipartite induced transparency,which represents a valuable step towards quantum networks with photonic and phononic circuits.

关键词： optomechanical system optomechanically induced transparency optical mode