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 共查询到19条相似文献,搜索用时 125 毫秒
1.
FORCEDOSCILLATIONSOFBOUNDARYVALUEPROBLEMSOFHIGHERORDERFUNCTIONALPARTIALDIFFERENTIALEQUATIONSJinMingZhong(靳明忠),DongYing(董莹),Li...  相似文献   

2.
AMODELIDENTIFICATIONMETHODOFVIBRATINGSTRUCTURESFROMINCOMPLETEMODALINFORMATIONZhengXiaoping(郑小平)YaoZhenhan(姚振汉)QuShisheng(蘧时胜)...  相似文献   

3.
SOLUTIONSFORASYSTEMOFNONLINEARRANDOMINTEGRALANDDIFFERENTIALEQUATIONS¥DingXieping(丁协平)WangFan(王凡)(DepartmentofMathematics,Sich...  相似文献   

4.
SINGULAR PERTURBATIONS FOR A CLASS OF BOUNDARY VALUE PROBLEMS OF HIGHER ORDER NONLINEAR DIFFERENTIAL EQUATIONSShiYuaning(史玉明)...  相似文献   

5.
QUASI-FLOWCORNERTHEORYONLARGEPLASTICDEFORMATIONOFDUCTILEMETALSANDITSAPPLICATIONSHuPing(胡平)LiuYuqi(柳玉启)GuoWei(郭威)TaiFeng(台风)(R...  相似文献   

6.
ITERATIVECONSTRUCTIONOFFIXEDPOINTSFORMULTIVALUEDOPERATORSOFTHEMONOTONETYPEINUNIFORMLYSMOOTHBANACHSPACESDengLei(邓磊)(ChongqingT...  相似文献   

7.
EXISTENCEOFSOLUTIONSOFTHREE-POINTBOUNDARYVALUEPROBLEMSFORNONLINEARFOURTHORDERDIFFERENTIALEQUATION¥GaoYongxin(高永馨)(Departmento...  相似文献   

8.
(何宗彦)ELASTIC-PLASTICCONSTITUTIVEMODELSBASEDONTHEMULTIPLICATIONPROCESSESOFDEFORMEDGRAINS¥HeZongyan(DepartmentofEngineerMechani...  相似文献   

9.
AUNIFORMLYCONVERGENTDIFFERENCESCHEMEFORTHESINGULARPERTURBATIONPROBLEMOFAHIGHORDERELLIPTICDIFFERENTIALEQUATION(刘国庆)(苏煜城)AUNIFO...  相似文献   

10.
SPECTRAL METHOD IN TIME FOR KdV EQUATIONS   总被引:1,自引:0,他引:1  
SPECTRALMETHODINTIMEFORKdVEQUATIONSSPECTRALMETHODINTIMEFORKdVEQUATIONS¥WuShengchang(吴声昌);LiuXiaoqing(刘小清)(ReceivedFeb.22,1995...  相似文献   

11.
The aim of this paper is to evaluate the effects of uncertain-but-bounded parameters on the complex eigenvalues of the non-proportional damping structures. By combining the interval mathematics and the finite element analysis, the mass matrix, the damping matrix and the stiffness matrix were represented as the interval matrices. Firstly, with the help of the optimization theory, we presented an exact solution—the vertex solution theorem, for determining the exact upper bounds or maximum values and exact lower bounds or minimum values of complex eigenvalues of structures, where the extreme values are reached on the boundary of the interval mass, damping and stiffness matrices. Then, an interval perturbation method was proposed, which needs less computational efforts. A numerical example of a seven degree-of-freedom spring-damping-mass system was used to illustrate the computational aspects of the presented vertex solution theorem and the interval perturbation method in comparison with Deif’s method.  相似文献   

12.
余本嵩  金栋平 《计算力学学报》2011,28(3):355-359,382
一维连续体的释放和回收过程由时变的动力学方程描述。将一维连续体离散为有限单元,建立其时变自由度的高维离散动力学模型。通过重新划分单元,重置系统质量、阻尼和刚度矩阵,以及位移和荷载向量,并基于改进的有限差分法,提出了一维连续体释放和回收过程的一种构形计算方法。以柔性索的面内运动为例,计算了其释放和回收过程的动力学构形,实...  相似文献   

13.
提出了一种线性动力学系统辨识方法.应用Padé多项式对系统的动刚度曲线进行拟合,通过最小二乘法确定Padé多项式中的系数矩阵,利用遗传算法确定出Padé拟合式中的参数.通过比较系统动刚度矩阵的理论公式和Padé拟合式,辨识得到系统的质量阵、刚度阵和阻尼阵.当系统阶数较高时,可结合POD降阶技术对系统进行辨识,该方法适用于全阶模型和降阶模型.数值仿真算例表明,论文方法具有较高的精度和较好的鲁棒性.  相似文献   

14.
本文从分析频率方程解的形式出发,通过设定响应的频域形式,得出自由振动时域响应的显式解,并导出任意强迫振动的Duhamel积分.文中的分析方法适用于系统质量、阻尼、刚度阵均为非对称的情形,且属于精确求解.  相似文献   

15.
基于复合材料层合板一阶剪切理论,推导了复合材料层合板单元的刚度阵和质量阵列式;同时采用了Adams应交能法与Rayleigh阻尼模型相结合的方法,构造了相应的阻尼阵列式;为了防止在低阶模态中分层处出现的上、下子板不合理的嵌入现象,建立了含分层损伤复合材料加筋层合板动力分析的分层分析模型和虚拟界面联接模型。在上述模型和理论基础上,采用了Tsai提出的刚度退化准则和动力响应分析的精细积分法,对含分层损伤复合材料加筋层合板结构进行了动力响应和破坏分析。通过算例,分别讨论了外载频率、分层位置,以及破坏过程的刚度退化对含损伤复合材料加筋层合板动力响应特征的影响,得到了一些具有理论和工程价值的结论。  相似文献   

16.
Considered are systems of single-mass oscillators with different fractional damping behaviour. Similar to the classical model, where the damping terms are represented by first derivatives, the eigensystem can be used to decompose the fractional system in frequency domain, if mass, stiffness and damping matrices are linearly dependent. The solution appears as a linear combination of single-mass oscillators. This is true even in the general case such that stability and causality are insured by the same argumentation as used in the linear dependent case.  相似文献   

17.
Considered are systems of single-mass oscillators with different fractional damping behaviour. Similar to the classical model, where the damping terms are represented by first derivatives, the eigensystem can be used to decompose the fractional system in frequency domain, if mass, stiffness and damping matrices are linearly dependent. The solution appears as a linear combination of single-mass oscillators. This is true even in the general case such that stability and causality are insured by the same argumentation as used in the linear dependent case.  相似文献   

18.
给出了求解多自由度动力学系统响应的M atlab程序,这些程序基于振型叠加法可用于求解由质量矩阵M和刚度矩阵K以及常见阻尼矩阵描述的线性离散系统的时域和频域解.对于无阻尼系统,用户可以选择数值解或符号解析解(以时间或频率表示),并利用复模态叠加法计算了阻尼系统的数值解.总结了模态叠加方法下动力学响应的求解,并在简短的M atlab程序中实现.以三自由度系统和悬臂梁模型为例说明了程序的应用.这些程序也可用于工程应用中,通过对商用有限元软件包产生的质量和刚度进行后处理,产生感兴趣的时域和频域响应.  相似文献   

19.
In a damped linear system, for the free vibrations to be oscillatory with decaying amplitude, it is proven that the mass and damping matrices must be positive definite. Also, a certain matrix product involving the mass, damping and stiffness matrices must be commutative.  相似文献   

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