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The fluid film bearing-flexible rotor nonlinear system with squeeze film damper is modeled practically using the finite element method and the Hamilton principle.(3) The film forces produced by fluid film bearing and squeeze film damper are determined by finite element method at any moment, and the Jacobian matrix is also determined.(4) A method for analyzing the dynamics of a large system with local nonlinearities is presented. The stability and bifurcation of the equilibrium position and the unbalance responce of a fluid film bearing-flexible rotor system with squeeze film damper are investigated based on the assumption of an incompressible lubricant together with the long bearing approximation for fluid film bearing, short bearing approximation for squeeze film damper and the"π"film cavitation model.

主要研究内容包括下面几个方面：（1）对挤压油膜阻尼器-滑动轴承-转子非线性动力系统中的非线性现象进行了机理方面的研究；（2）应用有限元方法及Hamilton原理对复杂的挤压油膜阻尼器-滑动轴承-转子非线性动力系统进行了建模分析；（3）对滑动轴承及挤压油膜阻尼器中任一时刻的油膜力及相应的Ja-cobi矩阵的确定进行了分析；（4）对一类具有局部非线性的多自由度动力系统，提出了一种可以有效地分析其动力特性的方法；（5）采用实验与理论分析相结合的方法，对挤压油膜阻尼器-滑动轴承-转子非线性动力系统的动力特性进行了分析。

The contents of this course include: the mathematical basis of FEM, the generic solution principles and expressions of elastic mechanics issue, the construction of element and its interpolation function, iso-parametric element and numerical integral, solution of linear equations, some practical issues of FEM modeling, brief introduction to typical commercial FEM packages, FEM for truss, plate blending and shell, and FEM for heat exchange and dynamics.

课程内容主要包括：有限单元法的数学基础、弹性力学问题有限单元法的一般原理和表达格式、单元和插值函数的构造、等参单元和数值积分、线性方程组解法、有限元建模的若干实际问题、典型商用有限元分析软件简介、杆件结构力学问题的有限单元法、平板弯曲问题的有限单元法、一般壳体问题的有限单元法、热传导问题的有限单元法、动力学问题的有限单元法等。

Based on the variational principle of virtual voltage and virtual displacement derived in this thesis and the classical theory of linear laminated plates, and by using the constitutive equations of elastic piezoelectric materials, and the DKQ quadrilateral plate bending element, the finite element modeling for the fabric reinforced laminated plates with nonlinear voltage-electric strain relationship of piezoelectric actuators has been established for the first time in this thesis. And the expressions for the electric loadings with obvious mechanical meaning and convenient for computation are established, which can be used to the deformation analysis of laminated plates with piezoelectric actuators under specified voltages.

以本文直接导出的压电结构的虚电势—虚位移变分原理为基础，依据经典线性层合板理论和压电弹性体的本构方程，采用基于离散法线假设的DKQ四结点任意四边形薄板弯曲单元，首次建立了考虑非线性电压—电应变关系的含压电致动器的纤维增强型层合板的有限元分析模型，并推导建立了力学意义明确、便于计算的电荷载表达式，可用于指定电压条件下纤维增强型叠层合成板的变形分析。

According to structural characteristics of floating slab tracks, a track segment element was taken between two adjacent fasteners. For each element, rails were regarded as Euler beams supported by discrete viscoelastic supports. The fasteners and rubber supports were replaced by a linear spring and damp. So the vibration model of the floating slab track was established. In constructing vibration model of a metro train, each car of the metro train with two suspensions was modeled as a multi-rigid body system, in which rigid bodies were connected with each other by a linear spring and damp. Combining the potential energy of vertical vibration of the track with that of the metro train, the total potential energy of vertical vibration of the train and track was obtained. And then, the matrix equation of vertical vibration of the system was established using the principle of total potential energy with stationary value in elastic system dynamics and the "set-in-right-position" rule for formulating system matrices. The vibration responses of the system can be obtained by solving the matrix equation with the direct time integration such as Wilson-θ method.

摘 要：针对浮置板式轨道结构特点，取相邻2个扣件之间的轨道为1个轨段单元，钢轨视为连续弹性点支承Euler梁，浮置板视为弹性薄板，扣件系统及橡胶支座均模拟为线性弹簧及粘滞阻尼器，建立浮置板式轨道振动模型；将城轨列车中的车辆均离散为多刚体系统，各刚体之间通过线性弹簧及粘滞阻尼器相连，建立列车振动模型；将浮置板式轨道及列车振动势能叠加，得到系统竖向振动总势能；基于弹性系统动力学总势能不变值原理及形成系统矩阵的"对号入座"法则，建立此系统竖向振动矩阵方程；采用Wilson-θ逐步积分法求解此矩阵方程，得出此系统竖向振动响应。

In this paper, a lot of research works of algorithms of mining CAD has been done. Many important mine specialty graph operation algorithms have been put forward. The main results are as follows: polygons cut out algorithm, two close polygons mutual, merge and subtract algorithm, polygon vector fill, any vector polygons area calculating and sequence polygons or multifold which has the direction and region area calculating, curve smoothing, graph element search for any region, graph element attrib collect in any region, parallel polygon or vector intersection-point push out or pull in, ore reserves and grade calculating for any type polygon, mine spatial data searching and boundary line tracking and automatic link algorithm etc.

论文在矿山图形算法研究方面做了大量的工作，提出了许多有价值的矿山专业图形运算算法，主要算法有：多边形裁剪算法、闭多边形的加、减、并算法、多边形的矢量填充算法、任意有向多边形、有向多连域、有向多边形序列面积算法、多种曲线光滑算法、任意区域的图元搜索算法、任意区域图元属性提取算法、多边形平行外推/内缩算法、任意多边形储量品位计算、矿山空间数据搜索算法、界线的自动追踪和连接等。

It was different of contents of same mineral element inthe leaves of Malania olefera because of different areas, but the differences was notnotable. The influence of mineral element and soil elements on Malania olefera wasnitrogen, iron, manganese, zinc, potassium, copper from most to least, and four ofthem were belong to microelement. However, the lack of copper and serious lack ofzinc and iron in the soil influent the growth of Malania olefera. It had been made through the analysis of morphologic and anatomicalcharacteristics of root, stem, leaf, flower, fluid and seed that Malania olefera notonly had the primitive character but also had the evolution character, which had thevital significance on Olacaceae classification.

砂粒含量比大，通透性良好的土壤适宜蒜头果的生长；六个不同分布区土壤的有机质和全N含量极为丰富，速效K的含量水平中等，而土壤速效P的含量富贫差异较大；分布区土壤部分缺Cu，严重缺Zn、Fe；蒜头果叶片中的叶绿素含量与立地条件有着密切的关系；龙虎山样地立地条件比其他样地更适合蒜头果生长；不同立地上生长的蒜头果叶片中同一矿质元素含量有一定的差异，但差异不显著；土壤元素对蒜头果生长的影响由大到小依次为：N、Fe、Mn、Zn、K、Cu，其中四个是微量元素，而分布区土壤缺乏Cu，严重缺Zn、Fe而影响了蒜头果的生长发育。

In chapter three, the new concepts of the bifurcation point and asymptotic bifurcation point of compact continuous operators in Menger PN-spaces are introduced. Some sufficient conditions for the existence of the bifurcation point and asymptotic bifurcation point are obtained. And the problems on the intrinsic value and intrinsic element of compact continuous operators are studied in Menger PN-spaces. A series of theorems on the existence of the intrinsic value and intrinsic element are obtained.

第三章，在概率赋范线性空间中提出非线性算子的歧点和渐近歧点的新概念，获得了非线性算子存在歧点和渐近歧点的充分条件；讨论了Menger概率赋范线性空间中非线性算子的固有值和固有元问题，得到了非线性算子存在固有值和固有元的一系列充分条件。

Then the boundary element integral equation of interior and exterior form is deduced in detail, also the form with corner coefficient. The significance for numerical calculation and principle of the singular integral is analyzed, and a non-isoparametric transformation method is presented to calculate weak singular integral and Cauchy integral, the method presented provides us a very simple way to computer the two kinds of singular integral of Helmholtz boundary integral equation, and it is easy to program in computer. After the difficulty of the calculation for multi-frequency of Helmholtz boundary element is explained, a method named SECHIEF (Series Expansion Combined Helmholtz Integral Equation Formulation), which is focused on the computational efficiency, is presented.

对结构声辐射的边界积分方程的内部形式与外部形式进行了详细的推导，给出了角点系数的计算方法与边界积分方程的形式，在此基础上，分析了奇异积分产生的原理及其对数值计算的重要性，提出了一种计算奇异积分的非等参(来源：Ae8a8BC论文网www.abclunwen.com)单元的变换方法，该方法给Helmholtz 声学边界积分方程中的弱奇异积分与Cauchy 奇异积分的计算以及编程提供了极大便利。

Firstly, according to electromagnetic field theory, the 2-dimensional (2-D) mathematical model of a three phase squirrel-cage Y802-2 induction motor is developed. Then general equations can be deduced from finite element discrete and functional analysis. The motor's 2D solving region of electromagnetic field is given based on the boundary conditions and assumption conditions of the squirrel-cage induction motor. Through finite element mothod and inner–outer convergence method, magnetic field distributions and magnetic forces of bars can be calculated in following rotor conditions: health rotor, one single broken bar, two adjacent broken bars, two broken bars with one good interval, two broken bars with two good interval and four adjacent broken bars.

本文首先根据电磁场理论建立Y802-2型三相笼型感应电动机二维电磁场的数学模型，并对其进行了有限元离散以及泛函分析，推导出总体方程；在基本假设和边界条件基础上，给出笼型感应电动机二维电磁场的求解区域，然后应用有限元并结合内外双收敛方法，对样机稳态运行进行数值计算，得出电机在转子完好、一根导条断裂、连续两根导条断裂、间隔一根两根导条断裂、间隔两根两根导条断裂及连续四根导条断裂六种情况下的磁场分布和导条所受电磁力的变化情况。

In chapter 2, a finite element model for the composite sandwich plates is developed, based on the Zig-Zag deformation assumption and the first order shear deformation theory, and the finite element buckling analysis governing equations for the plates under mechanical, thermal and/or thermal-mechanical mixed loads are deduced respectively. By Von-Karman nonlinear deformation relations and Total Lagrange formulation, an incremental governing equation for postbuckling analysis is established and a corresponding effective computational scheme is presented..

第二章首先建立了基于Zig-Zag截面变形假定和Mindlin一阶剪切理论的夹层板有限元分析模型，分别推导了夹层板机械力、热载和热—机械力耦合屈曲分析的有限元列式和相应的屈曲前以及屈曲临界状态的平衡方程，基于Von-Karman大挠度理论，采用增量形式的全局lagrangian法推导了复合材料夹层板增量形式的几何非线性有限元离散平衡方程，给出了一种有效的非线性平衡方程的迭代求解格式。

Molecular Distillation is a kind of high vacuum distillation method, which is suitable for the separation of high boiling, heat sensitivity and viscidity products.

分子蒸馏技术是一种在高真空条件下进行的连续蒸馏过程，适合于分离高沸点、热敏性及具有生物活性的混合物。

They are to the Noughties what yuppies were to the Eighties .

那在六十年代是时髦的，但在八十年代肯定是过时了