查询词典 stochastic dynamic model

A stochastic model with initial stochastic conditions and stochastic coefficients for surge calculation was developed for the typical hydraulic system of a surge tank .

针对典型调压室水力系统，建立了具有随机初始条件和随机系数的涌波分析随机模型，从数学上严格证明了调压室涌波随机模型存在唯一的均方解，并进一步利用Liouville定理求解了其解过程的联合概率密度函数，最后给出了调压室涌波的均值解曲线

Initially, assuming that the contact between cam and tappet is"dry contart", a dynamics model of Hertzin contact stiffness and impact damping is established. Next, with dynamic load on cam—tappet pair from the model, an analysis is made both to unsteady EHD oil film in cam—tappet pair under condition of full and partial lubrtication and to wear characteristics of cam profile. then, according to the fact that the lubrication in cam—tappet contact surface is EHD lubrication, taking the interaction between stiffness and damping of unsteady EHD oil film and rigidity of solid object contact into account, a dynamics equation of valve train relating to the dynamic effect of EHD oil film is built up and solved. Consequently, a further study is made on the dynamic characteristics of valve train under interaction of EHD oil film dynamic behavior and the problem of EHD lubrication in cam—tappet pair. Finally, the dynamic effect of full and partial EHD oil film is studied accordingly.

首先，通过对凸轮—挺杆接触为&干接触&的假设，建立了考虑赫兹&接触刚度&和冲击&阻尼&的配气机构动力学模型，用由此求得的凸轮—挺杆表面动载荷对凸轮—挺杆进行了全膜状态和部分膜状态非稳态弹流润滑分析，并研究了凸轮轮廓的磨损规律；然后，是在凸轮挺杆表面存在弹流动压油膜这一事实的基础上，相当于在动力学方程中考虑非稳态弹流油膜的&刚度&、&阻尼&和固体接触&刚度&的耦合作用，建立并求解了考虑弹流润滑行为动力学效应的配气机构的动力学方程，从而深入地研究了弹流润滑行为与动力学行为耦合作用下的配气机构动力学特征以及凸轮挺杆弹流润滑问题；作为前面工作的对应部分，考虑弹流油膜动力学效应的研究工作也同样分为全膜状态和部分膜状态进行。

Based on the general dynamic programming, in the grey dynamic programming model combined with the grey theory, the runoff is described by the interval grey numbers. The model is combined by the advantages of determinant/stochastic dynamic programming methods, it will be a new idea for the reservoir operation.

利用区间灰数描述径流，在普通动态规划的基础上融合了灰理论的灰色动态规划模型，综合了确定型动态规划方法和随机型动态规划方法的优点，为水库调度的动态规划应用研究提供了新的思路。

The results indicate that its dynamic stress-strain curve is hyperbolic type. The dynamic strain of LCES decreases with increasing confining pressure, cement content, curing ages and cyclic loading frequency when it is subjected to the same dynamic stress. At the same dynamic strain, the dynamic secant elastic modulus E_(sec of LCES increases and the damping ratio decreases with increasing confining pressure, cement content, curing ages and cyclic loading frequency. The curves ofσ_d～ε_d,E_～ε_d and D～ε_d with different EPS content intersect respectively, the trend of LCES deformation characteristic is inversely proportional to EPS content near the intersection. The value of dynamic strain at the intersection is about 0.5%~3.0%, the magnitude of which is related to the mixing proportions and confining pressure.

试验结果表明，LCES的动应力应变骨干曲线形态符合双曲线；在相同的动应力作用下，LCES产生的动应变随着固结压力、水泥掺量、试样养护龄期和振动频率的增大而减小；在动应变相同的情况下，随着固结压力、水泥掺量、试样养护龄期和振动频率的增大，LCES的动模量增大而阻尼比减小；随着加载次数的增大，LCES的动模量在开始阶段显著降低，然后趋于稳定，但当加载次数达到几百次时，动模量又有增大的趋势；不同EPS掺入比的LCES的动应力应变骨干曲线、动模量随应变变化曲线和阻尼比随应变变化曲线都发生了相交，交点前后EPS掺入比的大小对LCES动力变形特性的影响趋势是截然相反的，交点处的动应变值一般在0.5％～3.0％范围内变化，其大小与LCES的配比以及固结压力有关。

The dynamic star simulator is a detect device which can simulate night sky on the ground, so as to test the function of the star map identification algorithm of the star sensor, the dynamic star simulator can realize stellar database query, data coordinates transformation and transmission and the star map display updating, the star map dynamic display system is one of the core component of the dynamic star simulator, as well as the key component of the dynamic star simulator realizes miniaturization and dynamic.

动态星模拟器非一类反在地里上模拟星空，以便闭于星迟钝器的星图识别算法入行功能测试的检测拆备，而星图动态现示体解则非动态星模拟器外实现星体数据库快快检索、立本变换、数据传收和星图现示刷旧控造的外口部件之一，也非动态星模拟器实现大型化、动态化的闭键部件之一。

Fifthly, we research the problem about the stochastic fluctuate of the contents of organic compounds and microelements in the land under the assumption continuous-time model. The first, a dynamic model about fertility of plowland is presented using stochastic diffusion processes and distributed parameter system.

在分析了农业耕地中有机物含量及微量元素含量的随机变化过程的基础上，利用扩散随机过程理论及分布参数系统建立分析模型描述耕地肥力的分布状况；研究了以维护耕地最优质量状态作为目标值的最优控制问题。

The volatility of Chinese stock market is investigated using the dynamic version of stochastic volatility model, and Bayesian analysis based on MCMC is introduced to improve the parameters estimation in stochastic volatility model.

采用动态随机波动性模型实证研究了中国股票市场的波动性。通过基于马尔可夫链蒙特卡罗模拟的贝叶斯分析方法，较好地估计了随机波动性模型中的参数与波动性序列。

Biot's consolidation theory was used to serve as a frame working with the nonlinear elastic model or with elasto-plastic model in the program. Nonlinear elastic model includes Duncan-Zhang model, Gong Xiannan Ko consolidation model and the model proposed in chapter 2. Elasto-plastic model in the program includes Mohr-Coulomb model, Drucker-Prager model and the bounding surface model developed in chapter 3. The program can be used in cases of plane problem and axisymmtric problem.

FOR，针对软土地基的变形特点，该程序以Biot固结理论为框架，可以进行线弹性，非线性弹性和弹塑性的有限元计算，在非线性弹性模型中包括了Duncan—Chang模型、龚晓南Ko固结模型和本文建立的非线性模型，弹塑性模型中包拓了Mohr—Coulomb模型，Drucker—Prager模型以及本文中建立的边界面模型，该程序可以考虑平面问题也可以考虑轴对称问题。

This paper presents an IFMC CAD model that consits of a geometry model and a material model, in which the geometry space acts as a base space and the material space acts as a bundle space. In this CAD model, the geometry model is based on the non-manifold model. In addition, a half-face data sturucture, which is derived from the half-edge data structure with the non-manifold feature of IFMC taken into account, is adopted to represent the geometry and topology information of the component. For the material model of IFMC, this paper focuses on the FGM component representation firstly and present a simplex-subdivision based CAD data exchange format, in which the material information is represented as a (n-1) simplex and material distributing feature is represented by the interpolation on the simplex-subdivision. Based on those, a part-building orientation optimization algorithm and an adaptive slicing algorithm for FGM component are presented in the paper. For the IFMC material model, the IFMC material information representation is divided into a meso-scale and a macro-scale representation. In the meso-scale, a concept named parameterized periodic functional meso-structure is presented as a unique form to represent the FGM (the homogeneous materials are regarded as a special FGM), the composite and the functional meso-structure material. The model of PMS is a three-tuple that contains the space state informatation, the material parameter and the material meso-scale distribution feature. The macro-scale material information representation is similar to the FGM components by interpolation of the control parameter of the periodical functional meso-structure based on the simplex-subdivision. Through an example of manufacturing-oriented IFMC CAD data processing, it is proved that the IFMC CAD model and the material information representation and process method proposed in this paper can provide a reliable data support for IFMC digital concurrent design and manufacturing.

本文将理想材料零件CAD模型建立在以几何空间为底空间、以材料空间为丛空间的结构上，使用非流形几何模型作为理想材料零件几何拓扑模型的基础，并在半边数据结构基础上，针对理想材料零件的非流形特征局限内部边界上的特点，给出了一个半面数据结构来表述零件的几何拓扑信息；对于理想材料零件的材料模型，本文先从功能梯度材料零件的信息表述与CAD数据交换和处理入手，将材料信息表述为（n-1）维单纯形，然后通过对三维几何区域的单纯剖分，以插值的方式表述零件材料分布特征；在此基础上，根据功能梯度材料零件分层制造中对CAD数据处理的要求，给出了综合考虑零件几何特征与材料特征的生长方向优化算法和自适应切片算法；而对于文中所定义的理想材料零件，本文将其材料信息表述分解到细观和宏观两个尺度进行，首先给出了细观尺度上参数化的周期性功能细结构概念，以此来统一表述功能梯度材料（单质材料作为特殊的功能梯度材料看待）、复合材料和功能细结构材料；把周期性功能细结构模型化为一个包含空间状态信息、材料构成参数和材料细观分布特征参数的三元组，以表达零件的细观材料特征；对于零件宏观的材料变化特征，则同样在几何区域单纯剖分的基础上，通过对细观尺度上周期性功能细结构控制参数的插值来完成；通过理想材料零件CAD数据处理的算例，验证了本文中理想材料零件CAD模型及材料信息表述与处理方法完全可以为理想材料零件的数字化制造提供可靠的数据支持。

This paper presents an IFMC CAD model that consits of a geometry model and a material model, in which the geometry space acts as a base space and the material space acts as a bundle space. In this CAD model, the geometry model is based on the non-manifold model. In addition, a half-face data sturucture, which is derived from the half-edge data structure with the non-manifold feature of IFMC taken into account, is adopted to represent the geometry and topology information of the component.For the material model of IFMC, this paper focuses on the FGM component representation firstly and present a simplex-subdivision based CAD data exchange format, in which the material information is represented as a (n-1) simplex and material .distributing feature is represented by the interpolation on the simplex-subdivision. Based on those, a part-building orientation optimization algorithm and an adaptive slicing algorithm for FGM component are presented in the paper.For the IFMC material model, the IFMC material information representation is divided into a meso-scale and a macro-scale representation. In the meso-scale, a concept named parameterized periodic functional meso-structure is presented as a unique form to represent the FGM (the homogeneous materials are regarded as a special FGM), the composite and the functional meso-structure material. The model of PMS is a three-tuple that contains the space stateinformatation, the material parameter and the material meso-scale distribution feature. The macro-scale material information representation is similar to the FGM components by interpolation of the control parameter of the periodical functional meso-structure based on the simplex-subdivision.Through an example of manufacturing-oriented IFMC CAD data processing, it is proved that the IFMC CAD model and the material information representation and process method proposed in this paper can provide a reliable data support for IFMC digital concurrent design and manufacturing.

本文将理想材料零件CAD模型建立在以几何空间为底空间、以材料空间为丛空间的结构上，使用非流形几何模型作为理想材料零件几何拓扑模型的基础，并在半边数据结构基础上，针对理想材料零件的非流形特征局限内部边界上的特点，给出了一个半面数据结构来表述零件的几何拓扑信息；对于理想材料零件的材料模型，本文先从功能梯度材料零件的信息表述与CAD数据交换和处理入手，将材料信息表述为(n-1)维单纯形，然后通过对三维几何区域的单纯剖分，以插值的方式表述零件材料分布特征；在此基础上，根据功能梯度材料零件分层制造中对CAD数据处理的要求，给出了综合考虑零件几何特征与材料特征的生长方向优化算法和自适应切片算法；而对于文中所定义的理想材料零件，本文将其材料信息表述分解到细观和宏观两个尺度进行，首先给出了细观尺度上参数化的周期性功能细结构概念，以此来统一表述功能梯度材料(单质材料作为特殊的功能梯度材料看待)、复合材料和功能细结构材料；把周期性功能细结构模型化为一个包含空间状态信息、材料构成参数和材料细观分布特征参数的三元组，以表达零件的细观材料特征；对于零件宏观的材料变化特征，则同样在几何区域单纯剖分的基础上，通过对细观尺度上周期性功能细结构控制参数的插值来完成；通过理想材料零件CAD数据处理的算例，验证了本文中理想材料零件CAD模型及材料信息表述与处理方法完全可以为理想材料零件的数字化制造提供可靠的数据支持。

Metrorrhagia is also gynaecological problems of common diseases.

崩漏是妇科常见病也是疑难症。

WordFTP gives you the convenience and timesaving you need.

wordftp让您的方便和省时您所需要的。