On slippage induced by surface diffusion

The mechanism of surface diffusion is taken at the basis of the phenomenon of slippage of the contact line of a liquid film. With the aid of the condition of continuity of the traction vectors at the solid-liquid interface, we obtained an evolution equation for the velocity of the fluid particles at the wall which shows a marked resemblance with Millikan's equation for the slippage coefficient of gases and reduces, in the limit of small surface diffusivity, to the classical Stokes-Einstein model. The influence of surface roughness is explicitely taken into account and, among other results, cases of absence of slip caused by the attachment of the liquid film to the solid surface and of slippage solely induced by surface roughness are found. Finally, the effect of the surface deformation upon the surface velocity of the fluid particles is examined in some detail.     

天津通信企业IT信息存储支撑平台

天津通信企业IT信息存储支撑平台承载着天津通信关键业务支撑系统和主要的企业信息管理系统．为IT运营管理提供了高效、快速、稳定、安全的数据源，形成统一的存储平台。该平台采用了多系统存储资源集中共享的方式，通过海量数据的异构存储平台数据迁移实现了多系统的整合．达到多系统的数据资源共享。存储的整合为应用提供了可靠的资源保证，数据的整合则消除了信息孤岛，实现了数据共享。     

筒体结构连续化模型的弹性动力时程分析

本文用连续化模型对高层筒体结构在地震作用下的动力时程反应进行分析．     

一次国际设计竞赛的尝试--多维住宅设计

在后工业时代，建筑设计已经冲破了西方思维所惯用的二元对立方式的约束，呈现出日新月异的景象，建筑表皮的创作尤为突出。这个住宅设计是从四维分解到四维连续的一种大胆尝试，并引入拓扑学的基本方法处理动态空间。     

一种立方对称晶体结构的唯象连续非线性本构模型及其分析

基于立方对称结构的晶体特点，本文建立一种唯象连续非线性本构模型，推导出一些主要方向如（００１）、（０１１）和（１１１）受单向载荷时的表达式。并对所建模型的适用性进行了分析，指出在较高温度状态时所建模型能较准确地描述Ｎｉ基单晶的非线性变形。     

基于连续介质损伤力学的高强度钢板热成形性数值预测

基于连续介质损伤力学模型,建立耦合损伤的热成形本构方程。将该本构方程引入到自主开发的金属成形有限元软件KMAS中,从而可对高强度钢板在热成形过程中的损伤演化及成形性能进行预测。本构方程中与温度及应变率相关的损伤参数控制着热成形过程中的损伤演化,对成形性数值预测具有重要的意义。为标定本构方程中的损伤参数,进行不同温度及应变率下的等温热拉伸试验,并对拉伸过程进行数值模拟,通过优化对比数值计算和试验所得的力-位移曲线,获得了不同温度及应变率下的损伤参数。随后将损伤参数引入KMAS中,对一款典型汽车B柱在热成形过程的成形性进行数值预测,并与试验结果进行对比,结果证明了所建立耦合损伤本构方程的正确性。     

基于独立连续变量和复合指数函数的位移约束平面连续体结构拓扑优化

为了进一步研究连续体结构拓扑优化模型的合理性和可行性,基于独立、连续、映射( independent continuous mapping,ICM)方法,在满足结构位移约束的条件下,通过引入复合指数形式过滤函数对位移约束下质量最小化( minimum weight with a displacement constraint,MWDC)模型进行了改进,建立了基于独立连续变量和复合指数函数的位移约束平面连续体结构拓扑优化模型,并进行了优化求解。同时,利用M语言,基于Matlab软件平台,开发了相应的拓扑优化计算程序,并针对4种典型平面连续体结构进行了数值验证,分别比较分析了体积约束下的柔顺度最小化( minimum compliance with a volume constraint,MCVC)模型、MWDC模型以及改进的MWDC模型所得到的最优拓扑结构。数值结果表明：采用复合指数形式过滤函数改进的MWDC优化模型迭代次数更少,优化求解计算效率更高。     

基于Pro/E的结肠镜机器人的建模与仿真

连续型机器人是一种新型的仿生机器人。以所研制的结肠镜机器人样机为基础,基于Pro/E的运动仿真模块对结肠镜机器人单关节进行运动学分析,完成了万向环间的干涉检验,从而验证结肠镜机器人的结构设计可行。     

Continuum structural topological optimizations with stress constraints based on an active constraint technique

Stress‐related problems have not been given the same attention as the minimum compliance topological optimization problem in the literature. Continuum structural topological optimization with stress constraints is of wide engineering application prospect, in which there still are many problems to solve, such as the stress concentration, an equivalent approximate optimization model and etc. A new and effective topological optimization method of continuum structures with the stress constraints and the objective function being the structural volume has been presented in this paper. To solve the stress concentration issue, an approximate stress gradient evaluation for any element is introduced, and a total aggregation normalized stress gradient constraint is constructed for the optimized structure under the r?th load case. To obtain stable convergent series solutions and enhance the control on the stress level, two p‐norm global stress constraint functions with different indexes are adopted, and some weighting p‐norm global stress constraint functions are introduced for any load case. And an equivalent topological optimization model with reduced stress constraints is constructed,being incorporated with the rational approximation for material properties, an active constraint technique, a trust region scheme, and an effective local stress approach like the qp approach to resolve the stress singularity phenomenon. Hence, a set of stress quadratic explicit approximations are constructed, based on stress sensitivities and the method of moving asymptotes. A set of algorithm for the one level optimization problem with artificial variables and many possible non‐active design variables is proposed by adopting an inequality constrained nonlinear programming method with simple trust regions, based on the primal‐dual theory, in which the non‐smooth expressions of the design variable solutions are reformulated as smoothing functions of the Lagrange multipliers by using a novel smoothing function. Finally, a two‐level optimization design scheme with active constraint technique, i.e. varied constraint limits, is proposed to deal with the aggregation constraints that always are of loose constraint (non active constraint) features in the conventional structural optimization method. A novel structural topological optimization method with stress constraints and its algorithm are formed, and examples are provided to demonstrate that the proposed method is feasible and very effective. © 2016 The Authors. International Journal for Numerical Methods in Engineering published by John Wiley & Sons Ltd.