参数方程

The simulative model of temperature field and stress field in concrete , Heat and moisture coupling、Parallel simulative calculation of concrete with water pipe cooling、 Parallel feedback analysis of thermal characteristic parameters, and stress intensity factor of induced joint, which are the sixty-four-dollar questions, are studied in this dissertation. The main contents of this dissertation are as follows:(1)Based on the past and current research work, the calculation theory of the transient temperature field and creep stress field of mass concrete which self temperature influence is considered is deduced. The couple effect between the temperature field and humidity field of concrete, is considered on the basis of conservation law of water and energy, and the coupled formulation which coefficient is not constant of the heat and moisture in concrete is deduced. The calculation theory and model which is theoretically strict for solution to thermal problem in concrete with water-cooling pipes are recommended.

本文主要针对混凝土的温度场应力场仿真计算模型、热湿耦合、水管冷却问题的并行仿真、混凝土温度参数并行反演分析以及诱导缝应力强度因子计算等混凝土大坝温度应力数值仿真的关键技术进行了较为深入的研究，全文主要内容如下：(1)在现有研究基础上，推导了考虑自身温度影响的混凝土非稳定温度场和徐变应力场的计算理论；基于水分质量守恒和能量守恒原理考虑混凝土温度场和湿度场的耦合作用，推导了混凝土的变系数热湿耦合方程，并建立了相应的计算模型；引用严密的水管冷却混凝土温度场的计算理论和计算模型，比较了两种简化计算方法用于水管冷却混凝土仿真计算的不足。

By representing the uncertain parameters as interval numbers, the governed equations of the structure are obtained by means of the interval finite element method.

基于区间模型的结构静力分析将结构系统中的不确定性参数用区间数来表示，建立了系统的区间静力有限元控制方程。

And responses under the principal parametric resonance,superharmonic reso-nance and subharmonic resonance are discussed respectively.

文中分析了几类典型方程在退化情况下的局部稳定性，同时研究了一类较广泛的周期参数激励与外激励共存的系统在各种不同情况下的共振响应及其分叉行为，并用奇异性理论进行了分析，绘出了系统的分叉响应曲线。

Based on the solutions to Sylvester matrix equations, a parametric method for designing this observer is proposed.

基于Sylvester矩阵方程的解，提出了该观测器设计的参数化方法。

Under the frame of Hamiltonian, the propagation of seismic wave is a symplectic group transformation with one parameter and consequently, the numerical calculation methods of the propagation ought to be symplectic method.

在哈密顿表述下，地震波标量方程描述的波场随时间的演化过程为波场在单参数辛群作用下的变换过程。因而在计算地震波场随时间的演化时，为保持系统的辛性质，应采用辛几何算法。

To overcome the difficulties and drawbacks in modeling the dynamic systems by using traditional methods, a hybrid evolutionary modeling algorithm is proposed to model the dynamic system with a system of ordinary differential equations whose main idea is to embed genetic algorithm in genetic programming where GP is employed to optimize the structure of a model, and GA is employed to optimize the parameters of a model.

针对采用传统方法解决动态系统的微分方程建模问题所遇到的困难和存在的不足，文中设计了将遗传程序设计与遗传算法相嵌套的混合演化建模算法，以遗传程序设计优化模型结构，以遗传算法优化模型参数，成功地实现了动态系统的常微分方程组建模过程自动化。

By applying theory of displacement mat rix the equations have to be salisfied by parameters of mechanism with a first o rdered osculation at three points of a given straight line tangential to curve o f connecting rod were derived, and at the same time enable the equations to sati sfy the condition of velocity's direction by way of se...

应用位移矩阵理论推导了连杆曲线与给定直线在三个点上一阶密切时机构参数应满足的方程，同时通过设定机构初始位置，使其能够满足速度方向条件。也给出了用该方法综合的几个机构实例和一个应用实例。

In the paper,we studied the identification of the parameter of telegraph equation Wtt+ a1Wt+ b1W =c21Wxxwith periodical boundary conditions.

文章研究了一维电报方程 Wtt+a1 Wt+b1 W =c21 Wxx 在周期边界条件下的参数识别问题。

To solve the problem, a method used to analyze the proximity effect in rectangular loss transmission line is proposed and applined in full transverse electromagnetic frecuency Additionally, AC resistances are calculated to correct the parameters in telegraphist's equation, so it is feasible to do transmission characteristics analysis in wide band.

针对传统磁准静态方法无法进行高频段邻近效应分析的缺陷，提出一种可适用于横电磁波下整个频段的矩形有损传输线邻近效应分析方法，并推导了邻近效应影响下的交流阻抗，进而对电报方程的阻抗参数进行修正，为宽频域信号传输特性分析提供了新思路。

When nitrite accumulation occurred temperately in the system, piecewise zero-order kinetic model and dynamic model based on Monod equations were both used to describe the experimental data, and related parameters were analyzed.

在系统亚硝酸盐暂时积累条件下，分别采用分段零级动力学模型和基于Monod方程的动态模型，拟合试验数据，并求算相应的动力学参数。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。