Dynamic Analysis of Structural Columns Subjected to Impulsive Loading

For a building structure subjected to impulsive loading, particularly shock and impact loading, the response of the critical columns is crucial to the behaviour of the entire system during and after the blast loading phase. Therefore, an appropriate evaluation of the column response and damage under short-duration impulsive loading is important in a comprehensive assessment of the performance of a building system. This paper reports a dynamic analysis approach for the response of RC columns subjected to impulsive loading. Considering that the dynamic response of a column in a frame structure can also be affected by the floor movement which relates to the global vibration of the frame system, a generic column-mass model is used, in which a concentrated mass is attached to the column top to simulate the effect of a global vibration. To take into account the high shear effect under impulsive load, the model is formulated using Timoshenko beam theory, and three main nonlinear mechanisms are considered. Two typical scenarios, one under a direct air blast loading, and another under a blast-induced ground excitation, are analyzed and the primary response features are highlighted.     

大学生分层心理危机预警管理体系的构建

顺应社会发展,越来越多的优秀人才涌现出来,社会竞争也日趋激烈,这些压力作用于心理还未完全成熟的大学生,使大学生心理问题越来越突出,由大学生心理危机引发的恶性事件时有发生。因此,为了给学生营造一个和谐的校园氛围,进行高校大学生心理危机预警研究是十分必要的。本文首先提出了大学生心理危机预警指标体系,建构了基于结构方程的预警模型,最后结合本校100个学生样本的预警结果提出了大学生心理危机预警五级响应系统。     

用线性回归方法分析股票市场发展与经济增长

本文在前人的研究成果上,运用线性回归分析方法和基于向量自回归模型(Vector Autoregression,VAR)框架下格兰杰因果检验和冲击响应方法,讨论了中国股票市场和经济增长的关系.分析表明股票市场规模扩张冲击对经济增长的动态影响十分微弱.     

ZnO/Si异质结光响应研究型综合实验设计

设计了"ZnO/Si异质结光响应研究"的研究型综合实验。实验设计包括前期调研、ZnO/Si异质结的制备、测量电路设计及计算结果分析讨论3部分,并在此基础上进行实验拓展能力的培养,实验内容密切联系学科发展前沿。教学实践证明,研究型综合实验有助于学生提高专业知识综合应用能力,有助于创新型、科研型人才的培养。     

强非局域介质中的变分椭圆高斯型光孤子

运用变分法研究傍轴椭圆高斯光束在具有椭圆对称响应函数的强非局域非线性介质中的传输特性,得到了光束各参量的演化方程和演化规律.在强非局域非线性介质的椭圆对称响应函数的特征参量满足一定条件下,得到了一个临界功率,当光束初始输入功率等于临界功率时,可以得到变分椭圆高斯型空间光孤子.     

响应式Web设计档案移动信息服务新方式

档案移动信息服务存在部分WAP网站用户体验不佳、APP开发运营成本与利用效益的反差、微平台侧重于宣传与普惠档案服务的局部发展、档案移动应用建设困于成本高、技术难、资源共享难的问题之中.应用响应式Web设计技术可提升用户体验、增加利用效益、传递全方位信息、助力解决“钱、技、共享”难题等.应用此技术档案馆也将面临开发成本资金筹措、技术合作、浏览器等问题,并提出众筹助力解决开发成本、“产学研”为导向与高等学校技术合作,鼓励用户更新浏览器等解决方法.     

Finite element analysis of dynamic response and structure borne noise of gearbox

A dynamic finite element method combined with finite element mixed formula for contact problem is used to analyze the dynamic characteristics of gear system. Considering the stiffness excitation, error excitation and meshing shock excitation, the dynamic finite element model is established for the entire gear system which includes gears, shafts, bearings and gearbox housing. By the software of I-DEAS, the natural frequency, normal mode, dynamic time-domain response, frequency-domain response and one-third octave velocity grade structure borne noise of gear system are studied by the method of theoretical modal analysis and dynamic response analysis. The maximum values of vibration and structure borne noise are occurred at the mesh frequency of output grade gearing.     

椭球颗粒复合体系中的有效非线性光学响应

利用微扰展开法讨论了任意阶弱非线性椭球颗粒复合体系(假定颗粒组分的介电函数随场变化,表示为cε~=cε cχ|Ec|β)的有效介电响应,导出了稀释极限下两组分椭球颗粒体系的有效线性和有效(β 1)次非线性系数的一般表示式。结果表明,体系的有效非线性系数eχ依赖于颗粒的形状。     

用三要素法求解一阶电路暂态过程

本文阐述用三要素法求解一阶电路的思路和解题方法。     

巧用Authorware中的按键响应制作选择题

相比于Powerpoint，Authorware具有强大的交互功能，利用其中的按键响应可以很轻松地实现选择题的制作。