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Acta Mathematica Sinica,English Series 2019年第12期35卷 1979-1982页

作者： Xiao Ming DU xue Zhi ZHAO School of Mathematics South China University of TechnologyGangzhou 510640P.R.China Department of Mathematics Capital Normal UniversityBeijing 100048P.R.China

The set of self-mapping degrees of S^3-geometry 3-manifolds in[2]have some mistakes when the fundamental group of the 3-manifold is D4n^*,O48^*,D'n·2q or T'8·*** we need to make this *** self-mapping degrees of all closed and oriented 3-manifolds are listed in[1]and[5].The table of spherical case in[5]is mostly quoted from[2].The results in[5]which do not involve the corrections made here still *** results in[5]involving the corrections made here should be also changed.

关键词： Mapping degree spherical manifold

Profile characterization and temperature dependence of droplet control on textured surfaces

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Chinese Science Bulletin 2011年第18期56卷 1930-1934页

作者： FENg RuoTao WU xueDong xue qunJi Ningbo Institute of Material Technology and Engineering Chinese Academy of Sciences Ningbo 315201 China graduate University of the Chinese Academy of Sciences Beijing 100049 China

Droplet control on textured surfaces has attracted much attention in the fields of drag reduction and high-efficiency microreactors. We investigated the profile characterization and temperature dependence of droplet control between wetting and non-wetting on a series of textured silicon surfaces. Surfaces were fabricated using photolithography, and the temperature-dependent wettability of the single phase regime droplets was characterized using dynamic contact angle measurements. The experiments demonstrated that the profile of textured surfaces characterizes the droplets Leidenfrost point. The Leidenfrost point is proportional to the micro-pillar size and rectangular wave-length of the textured surface and is inversely proportional to ambient temperature. The Leidenfrost droplets moved freely on the textured surface, almost without hysteresis. Droplets could be directed on the surface of microreactors with a low driving force.

关键词：表面纹理温度控制液滴特性微反应器温度依赖性接触角测量润湿性

Existence of Entire Solutions for Semilinear Elliptic Problems with Convection Terms

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Journal of Mathematical Research with Applications 2015年第4期35卷 417-424页

作者： Hongtao xue Mathematics and Physics Teaching Department Yantai Nanshan University

By a sub-supersolution method and a perturbed argument,we show the existence of entire solutions for the semilinear elliptic problem-△u + a(x)|▽u|~q = λb(x)g(u),u > 0,x ∈ R~N,lim(|x|→∞) u(x) = 0,where q ∈(1,2],λ> 0,a and b are locally Holder continuous,a ≥0,b > 0,(?)x∈ R~N,arid g ∈ C~1((0,∞),(0,∞)) which may be both possibly singular at zero and strongly unbounded at infinity.

关键词： semilinear elliptic equation entire solution convection term existence

Complement factors C1q, C3 and C5b-9 in the posterior sclera of guinea pigs with negative lens-defocused myopia

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International Journal of Ophthalmology(English edition) 2015年第4期8卷 675-680页

作者： Ting-Ting gao qin Long xue Yang Department of Ophthalmology Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College

· AIM: To investigate the expression of complement factors in the posterior scleral fibroblasts of guinea pigs with negative lens-defocused myopia.· METHODS: Eighteen guinea pigs were assigned randomly to two groups: the negative lens-defocused group(NLD group, n =9) and the normal control without treatment group(NC group, n =9). The effect of myopic induction was compared in three subgroups: eyes treated with a-10.00 D negative lens in the NLD group(NL group), eyes treated with a plano(0 D) lens in the NLD group(PL group), and untreated right eyes in the NC group(NC group). The following analyses were conducted at four weeks: examination of the refractive error via retinoscopy, assessment of complement C5b-9expression in the posterior scleral fibroblasts using immunohistochemistry, and measurements of complement C1 q and C3 protein levels in the posterior sclera by Western blot.·RESULTS: After an induction period of four weeks, a significant myopic shift was detected in the eyes of the NL group, relative to that of the PL and NC groups(P gnificant increase in the percentage of C5b-9 immunopositive fibroblasts in the posterior sclera of the NL group eyes, compared to the PL group(q =11.50, P gnificantly higher levels of C1q(q =4.94, P =0.01) and C3(q =4.07, P =0.03)protein were detected in the posterior sclera of NL group eyes, compared to the PL group. There were no significant difference between the PL and NC groups for C5b-9(q =2.44, P =0.10), C1q(q =1.55, P =0.53) and C3(q =0.98, P =0.77) in the posterior sclera.·CONCLUSION: The data from present study provide evidence of the up-regulation of C5b-9, C1 q and C3 in the posterior scleral fibroblasts in a NLD myopic animal model. The results suggest that the complement system may be involved in the development of myopia.

关键词： experimental myopia complement factors sclera inflammation

Backstepping Control of Speed Sensorless Permanent Magnet Synchronous Motor Based on Slide Model Observer

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International Journal of Automation and computing 2015年第2期12卷 149-155页

作者： Cai-xue Chen Yun-Xiang Xie Yong-Hong Lan School of Electric Power South China University of Technology School of Information Engineering Xiangtan University

This paper presents a backstepping control method for speed sensorless permanent magnet synchronous motor based on slide model observer. First, a comprehensive dynamical model of the permanent magnet synchronous motor(PMSM) in d-q frame and its space-state equation are established. The slide model control method is used to estimate the electromotive force of PMSM under static frame, while the position of rotor and its actual speed are estimated by using phase loop lock(PLL) method. Next,using Lyapunov stability theorem, the asymptotical stability condition of the slide model observer is presented. Furthermore, based on the backstepping control theory, the PMSM rotor speed and current tracking backstepping controllers are designed, because such controllers display excellent speed tracking and anti-disturbance performance. Finally, Matlab simulation results show that the slide model observer can not only estimate the rotor position and speed of the PMSM accurately, but also ensure the asymptotical stability of the system and effective adjustment of rotor speed and current.

关键词： Permanent magnet synchronous motor(PMSM) slide model observer backstepping control speed sensorless alternating current(AC).

Single t-quark Productions via Flavor-Changing Processes in Topcolor-Assisted Technicolor Model at Hadron Colliders

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Communications in Theoretical Physics 2008年第1期49卷 193-198页

作者： XU Wen-Na WANg xue-Lei XIAO Zhen-Jun Department of Physics and Institute of Theoretical Physics Nanjing Normal University Nanjing 210097 China College of Physics and Information Engineering Henan Normal University Xinxiang 453007 China

In the framework of topcolor-assisted technicolor （TC2） model, there exist tree-level flavor-changing （FC） couplings, which can result in the loop-level FC coupling tcg. Such tcg coupling can contribute significant clues at the forthcoming Large Hadron Collider （LHC） experiments. In this paper, based on the TC2 model, we study some single t-quark production processes involving tcg coupling at the Tevatron and LHC： pp（pp） → tq （q = u, d, s）, tg. We calculate the cross sections of these processes. The results show that the cross sections at the Tevatron are too small to observe the signal, but at the LHC it can reach a few pb. With the high luminosity, the LHC has considerable capability to find the single t-quark signal produced via some FC processes involving coupling tcg. On the other hand, these processes can also provide some valuable information of the coupling tcg with detailed study of the processes and furthermore provide the reliable evidence to test the TC2 model

关键词： topcolor-assisted technicolor model flavor-changing couplings hadron colliders electroweak symmetry breaking

3D pseudo-seismic imaging of transient electromagnetic data-a feasibility study

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3D pseudo-seismic imaging of transient electromagnetic data-...

轨迹断面特征根对受扰轨迹最远点及动态鞍点的诠释

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： g.q.xue L.-J.gelius L.Xiu Z.P.qi W.Y.Chen Institute of geology and geophysics Chinese Academy of Sciences Department of geosciences University of Oslo0316 OsloNorway Chang'an University College of geology Engineering and geomatics Chang'an University

We investigate a pseudo-seismic approach based on the so-called inverse q-transform as an alternative way of processing transient electromagnetic(TEM)*** technique transforms the diffusive TEM response into that of propagating waves obeying the standard *** transformed data can be input into standard seismic migration schemes with the potential of giving higher resolution subsurface images. Such images contain geometrical and qualitative information about the medium but no quantitative results are obtained as in model-based inversion *** reconstructed images can be used directly for geological interpretation or in further constraining possible *** extend the original q-transform based on an electrical-source formulation to the case of a large-loop TEM source,Moreover,an efficient discrete version of the inverse of this modified q-transform is presented using a regularization *** of this inverse transform to the measured TEM responses gives the corresponding pseudo-seismic data,which are input into a 3D migration *** then use a 3D boundary element type of Kirchhoff migration to ensure high computational *** proposed method was applied to both synthetic data as well as field measurements taken from an engineering geology survey. The results indicate that the resolution of the TEM data is significantly improved when compared with standard apparent-resistivity plots,demonstrating that higher resolution 3D transient electromagnetic imaging is feasible using this method.

关键词： Transient electromagnetic field Pseudo-seismic field Inverse qtransform Kirchhoff integral method 3D TEM imaging

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电力系统自动化 2010年第12期34卷 1-7页

作者：薛禹胜郝丽丽 q. H. WU L. JIANg 国网电力科学研究院/南京南瑞集团公司江苏省南京市210003 东南大学电气工程学院江苏省南京市210096 The University of Liverpool Liverpool L69 3GJ英国

对于任何复杂模型,通过仿真得到特定扰动下的受扰轨迹后,就可沿轨迹将系统模型等值为分段定常的线性系统。轨迹断面特征根法采用的假设与欧拉积分法完全相同,即系统在且仅在单个仿真步长内被定常线性化。因此,在每个积分步内,不但可用... 详细信息

对于任何复杂模型,通过仿真得到特定扰动下的受扰轨迹后,就可沿轨迹将系统模型等值为分段定常的线性系统。轨迹断面特征根法采用的假设与欧拉积分法完全相同,即系统在且仅在单个仿真步长内被定常线性化。因此,在每个积分步内,不但可用静态扩展等面积准则(EEAC)法分析该轨迹断面上的能量稳定裕度(轨迹断面能量),也可用平衡点特征根技术分析该轨迹断面上的振荡阻尼与瞬时频率,而将断面处的不平衡功率与动能视为初始扰动。完整的受扰轨迹成为大、小扰动稳定分析的共同基础,断面特征根可反映复杂因素对振荡特性的影响,而EEAC可反映复杂因素影响同步稳定性的本质。引入"轨迹断面虚拟平衡点特征根序列"的概念,以计入断面处动能对滑步失稳的影响,并将滑步失稳与振荡失稳两者的机理相关联。据此考证最远点(FEP)和动态鞍点(DSP)处的振荡阻尼与瞬时频率,揭示大、小扰动失稳的内在联系。

关键词：振荡模式特征根分析轨迹断面特征根动态鞍点(DSP) 最远点(FEP)

Microstructure-based finite element modeling of effect of metastable austenite on mechanical properties of quenching and partitioning (q&P)980 steel

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Journal of Iron and Steel Research International 2018年第11期25卷 1140-1148页

作者： Hui Zheng Wei Li Yu gong Li Wang xue-jun Jin Institute of Advanced Steels and Materials School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai Jiao Tong University Shanghai 200240China State Key Lab of Development and Application Technology of Automotive Steels Baosteel Research Institute Shanghai 201900China

The microstructure-based finite element modeling was conducted to study the mechanical properties of q&P 980 steel at the microscopic *** two-dimensional representative volume elements of real microstructure were obtained from electron backscattered diffraction ***-Kocks equation was used to predict the constitutive strain-stress relationships of individual ***-induced martensitic transformation takes place when the driving force exceeds the critical driving force according to a stress-invariant-based *** macroscopic stress-strain curves and the work-hardening rate curves obtained from modeling fit well with the experimental *** simulation results also indicate that the local distributions of stress and strain in constituent phases are dependent on their *** ferrite carries the highest strain,while hard mechanical-induced martensite carries the highest *** comparing the modeling results of the microstructures with and without austenite,it shows that the transformation of retained austenite to hard martensite can increase the .work-hardening ability and hence improve the strength and ductility of the *** detailed finite element modeling methods and results are presented and discussed.

关键词： q&P steel Retained austenite Mechanical property TRIP effect Finite element modeling