On doubly warped product Finsler manifolds

In this paper, we introduce horizontal and vertical warped product Finsler manifolds. We prove that every C-reducible or proper Berwaldian doubly warped product Finsler manifold is Riemannian. Then, we find the relation between Riemannian curvatures of doubly warped product Finsler manifold and its components, and consider the cases that this manifold is flat or has scalar flag curvature. We define the doubly warped Sasaki-Matsumoto metric for warped product manifolds and find a condition under which the horizontal and vertical tangent bundles are totally geodesic. We obtain some conditions under which a foliated manifold reduces to a Reinhart manifold. Finally, we study an almost complex structure on the tangent bundle of a doubly warped product Finsler manifold.     

Lax Connection of Strings in γ-Deformed Backgrounds

In this paper we consider classical strings propagating in γ-deformed AdS3 × S^3 backgrounds generated by TsT transformation on the AdS3 sector, which is described as the group manifold SL（2, R）, then we prove that the U（1） currents of strings with the twisted boundary conditions are equal to those in γ-deformed backgrounds. Using TsT transformation, we can derive the local Lax connection and the monodromy matrix in γ-deformed backgrounds with the spectral parameter, which ensures the classical integrability of the string theories.     

Epidemic Spread in Networks Induced by Deactivation Mechanism

We have studied the topology and epidemic spreading behaviors on the networks in which deactivation mechanism and long-rang connection are coexisted. By means of numerical simulation, we find that the clustering coefficient C and the Pearson correlation coefficient r decrease with increasing long-range connection μ and the topological state of the network changes into that of BA model at the end （when μ = 1）. For the Susceptible-Infect-Susceptible model of epidemics, the epidemic threshold can reach maximum value at μ = 0.4 and presents two different variable states around μ= 0.4.     

部分剪力连接钢—砼组合梁的滑移及曲率分析

对受均布荷载作用的简支部分剪力连接钢－砼组合梁的滑移应变和滑移的分布规律进行了理论分析,得出部分剪力连接钢－砼组合梁的剪力连接程度系数与滑移应变和滑移的关系。分析了考虑滑移效应的梁的曲率及其与剪力连接程度系数之间的关系。结果与结构在弹性阶段的实验相当吻合,对组合梁挠度的精确计算有指导意义。     

焊管的残余应力测试与研究

通过小孔法与分割法对φ272mm螺旋埋弧焊管和φ380mm对接焊管的残余应力测试,分析探讨了螺旋焊缝、环焊缝以及焊缝热影响区的残余应力分布。研究结果表明,不同工艺焊接成型的圆管,其焊缝纵向均匀为拉应力分布,焊缝横向均为压应力分布,焊缝热影响区的残余应力分布各异。     

利用变压器研究两个互感线圈的串并联

利用变压器研究了两个互感线圈串并联的等效电感。     

电磁热效应裂纹止裂的实验研究

通过本文给出的实验表明：利用电磁场的热效应对载流导体中的裂纹进行止裂是一种行之有效的方法。在电磁场作用瞬间,由于裂尖处的热集中效应,能够使其在附近一定范围内熔化形成微小焊口。由此,裂纹前缘处的曲率半径增加了2-3个数量级。同时,细化了裂纹前缘的显微组织,提高了材料的韧性,显著地减少了应力集中,阻止了干线裂纹源的形成,可有效地遏制了裂纹的扩展。文中介绍了实验原理、方法和结果;讨论了一些参数之间的关系。     

Flat Partial Connections on a Three Manifold Equipped with a Codimension One Foliation

Given a compact connected oriented three manifold, equipped with a codimension one foliation, such that the Bott connection on the normal bundle is flat, a 2-form on the space parametrizing flat partial connections on it has been constructed. This form is closed. In the special case where the foliated three manifold is a surface bundle over the circle, this 2-form is identified with a certain 2-form on the parameter space for a class of paths in the representation space for the surface group. The 2-form, in question, on the parameter space for paths is constructed from the natural symplectic form on the representation space for a surface group.     

ON THE CHERN CONNECTION OF FINSLER SUBMANIFOLDS

This paper studies the induced Chern connection of submanifolds in a Finsler manifold and gets the relations between the induced Chern connection and the Chern connection of the induced Finsler metric.Then the authors point out a difference between Finsler submanifolds and Riemann submanifolds.