查询词典 simultaneous differential equations

The coupling effect between elastic deformation and the rigid motion was concerned in the dynamic equations. At the same time, the flexible manipulators were assumed as Euler-Bernoulli beams, the elastic deformation of the manipulator was represented by modality truncation equations, both elastic and gravitational potential energy were considered to calculate the total energy for whole system, therefore the finial dynamic modeling is more accurate and simple than others published.

该方法考虑了柔性机械臂刚体运动和弹性变形之间的耦合影响，并将柔性机械臂假设为一段Euler-Bernoulli梁处理，将弹性变形用截断模态方程表示，同时考虑了弹性势能和重力势能的影响，得到的双连杆柔性机械臂的动力学模型具有模型准确、结构简单等特点。

Firstly, four geometric loop equations are set up by using vector method in complex number fields. Secondly, three constraint equations are used to construct the Dixon resultants, which is a 6×6 matrix and contain two variables to be eliminated. Extract the greatest common divisor of two rows and two columns of Dixon matrix and compute its determinant to obtain a new equation. This equation together with the forth constraint equation can be used to construct a Sylvester resultant.

首先使用矢量法和复数法建立4个几何约束方程式；再使用Dixon结式法对3个方程式构造一个含有2个变元的6×6 Dixon矩阵，提取其中2行列元素的公因式，将新矩阵的行列式展开后得到二元高次多项式方程，该方程与剩下一个方程使用Sylvester结式消去一变元，得到一元高次方程。

Maxwell's equations group in fact was already found in the basic experimental laws of electromagnetic phenomena, as well as a single magnetic pole does not exist on the facts and the integrated displacement current assumptions, using an international system of units, these equations can be written as: DivDW =ρ or DW =ρ(1) kiDivBq = 0 or Bq = 0 (2) kiCurlEBq =- Zt or × EqkZ =- BqZt (3) ZCurlHDWDW = jE Zt, or × HW = jE Zkt (4) Z-type in the Curl, and Div were vector operator curl and divergence, Micro-k points for the Hamiltonian operator, in the rectangular coordinate system,= iZZEkx jEy kqz, iE, jE, kq along Zx, y, z-axis unit vector, a vector for any AW are × AW = CurlAW, kAW = DivAW; DW for the electric displacement, Bq for the magnetic induction intensity, Eq, and HW, respectively i field and electric field strength, jY for the conduction current density,ρ the charge density for free.

麦克斯韦方程组实际上是当时已发现的电磁现象的基本实验定律以及单个磁极不存在的事实和位移电流假设的综合，采用国际单位制，这些方程式可写成：DivDW＝ρ或DW＝ρ（1）kiDivBq＝0或Bq＝0（2）kiCurlEBq＝－Zt或×EqkZ＝－BqZt（3）ZCurlHDWDW＝jE＋Zt或×HW＝jE＋Zkt（4）Z式中Curl和Div分别为矢量算符旋度和散度，为哈密顿微k分算符，在直角坐标系中，＝iZZEkx＋jEy＋kqz，iE，jE，kq是沿Zx、y、z轴的单位矢量，对任一矢量AW有×AW＝CurlAW，kAW＝DivAW；DW为电位移，Bq为磁感应强度，Eq和HW分别为电i场和磁场强度，jY为传导电流密度，ρ为自由电荷密度。

With the idea of finite approximation, we study a new solution method for the satellite altimetry problem. Our result shows that if the continental part of the earth is sphere cap, then the solution of satellite altimetry problem can be transformed into a linear system of equations with variants of the coefficients of spherical harmonic series. We prove that the linear system of equations is separated about the orders of spherical harmonic series.

研究了球界面下卫星测高问题的解法，利用有限逼近方法得到了下列结论：若陆地部分是球冠，则卫星测高问题的解可以转换成关于球谐级数位系数的线性方程组，并且位系数的阶和次是以分离形式出现的，从而确保该解法具有实用意义。

In this paper, we study the existence of global solution and its property of the initial boundary value problem for Camassa—Holm equations and Ginzburg—Landau equations.

本文研究了Camassa—Holm方程和Ginzburg—Landau方程初边值问题整体解的存在性及其性质。

This dissertation's main work and innovations is following: 1. The 6DOF kinematic and dynamic equations of motion for multiple thrusters AUV are derived and presented in a compact form using vector notation. The hydrokinetics of the MTAUV is classified anew. The MTAUV has two kinds of work modes which are cruising and hovering. The fluid dynamical mathematics description of the MTAUV is given anew. 2. The kinetics equations of the MTAUV in the low speed hovering are analyzed and studied.

本文主要的工作和创新点主要有以下几个方面：一、采用矢量参数的形式建立了基于多推进器自主水下航行器的六自由度运动学方程和动力学方程；对基于多推进器自主水下航行器的流体动力进行了重新分类，给出了基于多推进器自主水下航行器在巡航工作模式和悬停工作模式两种不同工作状态下流体动力的数学描述。

The flow of incompressible viscous fluid is controlled by Navier-Stokes Equations.The qualititave analysis of the solutions of the equation is important to the studies of bifurcation problems and numerical solutions of the equations.

对于描述不可压缩粘性流体流动的Navier-Stokes方程，其解的定性分析结果对于该方程的数值求解及其分歧问题的研究都是十分重要的。

The so-called indeterminate equation is the solution in the range of integers, positive integers, rational numbers or integers of the equation or algebraic equations, whose unknowns are usually more than the number of equations ...

所谓不定方程是指解的范围为整数、正整数、有理数或代数整数的方程或方程组，其未知数的个数通常多于方程的。。。

ABSTRACT Aiming at problems of trans-vector controller in a vehicle-carried induction motor such as variable rotor and stator resistance following motor temperature, and their inductance varying with flux saturation degrees. Firstly, CSI and VSI are introduced, for CSI, it can hold the advantages both FOC and DTC using stator flux directional, PI parameter and simulation are also introduced. Secondly, equations of IM in the synchronous rotary frame and its static counterpart, as figuring in the saturation condition of magnetic field, are dealt in this paper and the simulation results are presented. Thereafter, the parameter designing of PI trans-vector controller is processed, which features the non-linear model. In practical realization, as neglecting the dynamical change of motor inductance, this paper employs online modification of inductance parameters, according to the flux saturation, then transforms the non-linear equations into linear ones, and so compacts the structure of controller. Thirdly, in view of the maximum torque output is extraordinary requisite when Electrical Vehicle start up, accelerate, and overtake, this paper issues the maximum torque when both inverter and battery capacity is corporeally definite. Fourthly, on-line differentiating and analyzing both rotor's time constants and its flux by using the expanding order reduction and discrete Kalman filter equation are fathomed, in order to realize high-performance trans-vector algorithm, and also the simulation results are presented. Fifthly, the close-loop regenerative brake system, when the EV's torque is set constant, is deduced; at the same time, unification of electric drive model and brake model is executed. Combined with maximum charge current demands, the mathematical model for online yielding torque as a demand.

本论文针对车载异步电机在矢量控制器所遇到的问题：定转子电阻随温度变化及随电机饱和程度变化的转子电感及定子电感而影响电机调速性能提出一套完整的解决方案：分析了电流型逆变器和电压型逆变器在实现矢量控制时控制器参数的计算，分析出对于电流型逆变器在采用定子磁场定向时，其性能同时具有矢量控制和直接转矩控制两者的优势，并对电压型逆变器在转子磁场定向下的模型进行了仿真研究；建立异步电机非线性模型，推导出考虑磁饱和时异步电机在同步旋转坐标系及静止坐标系下的方程，并做出了仿真结果，建立异步电机在非线性模型下的矢量控制调节器的PI参数设计，在实际应用中，若忽略电机电感的动态变化，可以根据当前的磁路饱和状态而在线修正电感参数，从而将非线性方程线性化，降低控制器的复杂度；考虑到电动汽车在起动和加速超车时需要电机有最大转矩输出，本文讨论在逆变器容量一定和电池供电能力有限的情况下电机最大转矩输出问题；推导了异步电机扩展降阶、离散卡尔曼滤波方程在线辨识转子时间常数和转子磁通，用于实现高性能的矢量控制算法，并给出了仿真结果；推导出了电动汽车恒转矩给定的闭环回馈制动系统，实现了电动控制模型和制动模型的统一，而且结合铅酸电池最大充电电流的要求，为制动转矩在线给定建立了数学模型；设计了基于双DSP系统的高性能矢量控制器软硬件框图，并以大量实验数据说明矢量控制在电动汽车应用的实际应用状况。

In this article, we study the solutions of several operator equations and the stability of operator equations and inequalities.

本文研究了几类算子方程的解与算子方程和不等式的稳定性问题。

So it was last week in Selma , alabama.

上星期在亚拉巴马州塞尔马市发生的事件也是这样一个转折点。

The group also spearheads various social programs in China.

该组织还带头参与中国的各种社会活动。