查询词典 cubic equation

Based on them, we calculated precisely some enegy levels of P-wave and D-wave of a helium atom, presented and proved the general interdimensional degeneracies for a quantum N-body system, derived the general spherical spinor functions and the exact solution to the Dirac equation for the hydrogen atom, and proved uniformly the Levinson theorem for the Dirac equation in D-dimensions.

在此基础上，我们精确计算了氦原子P波和D波若干较低能级，建立和证明了量子N体系统不同维数状态间最普遍的简并，推导出任意 D 维空间广义球旋函数和Dirac方程氢原子的精确解，统一地提出和证明了任意 D维空间Dirac方程Levinson定理的一般形式。

The standard Camassa-Holm equation and the Degasperis-Procesi equation are chosen to illustrate the con-crete scheme of our approach.

选取标准的Camassa-Holm方程和Degasperis-Procesi方程以展示这种方法的具体格式。

The standard parabolic equation method was obtained by the decompocition of the scalar wave equation and the expansion of the pseudo-differential operator.

通过对传统波动方程的分解和伪微分算子的近似展开，获得了标准抛物线方程。

Quadratic Equation Solving Function - This function solves a standard quadratic equation .

这个函数求解一个标准的二次方程。

The beginning of this article gives the definition of elliptic curve, ellipse standard equation, and the long axis of oval, short, with an area of the formula of a binary quadratic equation of the circumstances under which the judge said to provide the basis of an oval, as well as the conditions in this the long axis of the ellipse, short, with an area of what is the formula?

本文开始给出了椭圆曲线的定义，椭圆的标准方程，及椭圆的长轴，短轴，面积公式，对一个二元二次方程在什么情况下表示椭圆提供了判断依据，以及在此条件下的椭圆的长轴，短轴，面积公式是什么？

For the four laterals simply supported plate, the transverse deflection of plate is expanded over the modal shapes, the electroelastic model with self-sensing actuators plate is given, and the current is considered as output variable of measurement equation. Generalized modal coordinates being state variables, LQG and H∞control is proceeded using the state space equation.

将板的横向位移按模态展开，对配置压电自感作动器的薄板建立了模型，给出以广义模态坐标为状态变量的状态方程和以传感电流为输出的观测方程，在此基础上，对系统进行了LQG控制和H∞控制。

In the fourth chapter, theoretical analysis was performed by using the stochastic oscillation theory, the stochastic averaging equation and the FPK equation were deduced and some simulation results about the stationary probability density function of such system were given.

第四章利用随机振动理论，对系统进行了一些理论分析，推导了此类系统的随机平均方程与FPK方程，并初步给出了一些关于系统响应的平稳概率密度的模拟结果。

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。

We structure a general equilibrium dynamic model of optimize behavior under the stick price, the model is made up of IS equation , AS equation and interest rate rule , these three equations :::: We utilize state space model and Kalman filter to measure the variable which can't be observed --The China Real Interest Rate Gap and China potential GDP .

我们构建了粘性价格下基于主体最优化行为的一般均衡动态模型，模型由IS方程、AS方程和利率规则这三个方程组成：：：：我们利用状态空间模型和卡尔曼滤波的方法对于不可观测变量——中国实际利率缺口和中国潜在GDP进行了度量。

Moreover, applying the theories of backward stochastic differential equation and partial differential equation, the models have been converted.

并借助于倒向随机微分方程以及偏微分方程的重要理论完成了对模型的转化。

The dissecting of samples in group2 were difficult. The root of pulmonary artery and ascending aorta failed to be unfolded because fibrous tissue was tough, right and left fibrous trigone were too firm to be solved by hand. Cardiac muscle fibers couldn't be stripped along myofibrillar trajectory since they were prone to break because of their friability.

组2的心脏解剖困难，表现为纤维组织坚韧，游离肺动脉非常困难；徒手无法松解左、右纤维三角，肺动脉和主动脉根部的游离非常困难；心肌纤维坚硬、质脆，解剖时容易断离成碎块，无法沿纤维走行方向剥离。

We have battled against the odds in a province that has become increasingly violent.

我们对在一个争夺日益激烈省的可能性。