参数方程

Based on the well-know Pennes'' bioheat equation,we calculated theoretically temperature field of HIFU-induced BFR in tissue,and measured spatial temperature rise in BFR induced by HIFU in freshly excised cow liver at constant acoustic intensity and exposure time, and studied the effects of the physical parameters of focused ultrasound transducer such as frequency,outer radius and curvature radius,focal depth, and acoustic intensity and exposure time on the temperature field of HIFU-induced BFR.

采用生物热传导方程理论计算了HIFU生物学焦域温度场，采用微型热电偶探针测量了HIFU辐照离体牛肝时靶组织温度分布；研究了聚焦超声换能器的物理参数、辐照深度和治疗剂量对HIFU生物学焦域温度场的影响；研究了HIFU在牛肝组织中的传播衰减。

It is verified that the dynamicequations of free-floating space manipulator systems can be linearlydependent on a group of inertial parameters.

系统动力学分析的结果表明，结合系统动量及动量矩守恒关系得到的系统动力学方程将为系统惯性参数的非线性函数。

In this thesis, using the integral equation theory and functional analysis, we prove the existence and uniqueness of the model solution.

但对于带有时滞的非线性的用偏微分方程描述的经济分布参数控制模型的研究，在以前的文献中还没有见到。

In last several years, there have been numerous publications on sensorless operation, but most of these techniques only rely on the fundamental machine equations, which limits the low speed and zero speed operation of the machine, and are sensitive to the machine parameters.

目前，永磁同步电动机无位置传感器控制技术的研究已经取得了丰硕的成果，但大多依赖于对电动机基波方程的分析，不适于低速及零速下应用，而且对电动机的参数非常敏感。

To overcome the difficulty caused by the fact that the Lax pair depends on thesolution of the equation as |k|→∞,we write the Darboux matrix with N-poles inthe form:〓,where factor 〓 is a gauge transformation which isindepent from k and 〓 tends to the unit-matrix I as |k|→∞.

为了克服当|k|→∞时，Lax对仍依赖于方程的解所引起的困难，我们把含N对极点的Darboux矩阵〓分解为两部分：〓，其中〓为与参数k无关的2×2矩阵，它相当于一个规范变换。而〓当|k|→∞时趋于单位矩阵I。

The applications of Matlab in engineering calculation of unit operations by exemplifying several typical calculations involved nonlinear equation,interpolation,numerical integration,graphic method and log coordinate drawing are discussed.

以几个典型问题为例，讨论了Matlab在求解非线性方程及方程组、插值法获取物性参数、积分、绘图计算及对数坐标图的绘制等化工原理工程计算中的应用。

The influence of the parameters such as the grid shape and size, parameters of equation of state and artificial viscosity coefficients, etc.

通过数值模拟分析了网格形状、网格密度、状态方程参数、人工粘性对计算结果的影响。

However the lower order traditional absorbing boundary conditions are only effective for the incident waves with smaller incident angles. A fourth-order absorbing boundary condition equation based on Higden's ABC is deduced in this thesis, and a new algorithm is presented to automatically select the Higden's parameters.

本文基于Higdon提出的吸收边界条件方法，推导出四阶吸收边界条件方程，并提出了一种新的吸收边界条件角度参数的自动选择方法，使该吸收边界条件能够吸收全角度(0～90度)入射波。

A fourth-order absorbing boundary condition equation based on Higdon's ABC is deduced in this paper, and a new optimal algorithm is presented to automatically select the parameters of Higdon's ABC.

本文基于Higdon提出的渐进吸收边界条件方法，推导出四阶吸收边界条件方程，并提出了一种新的吸收边界条件角度参数的优化选择方法。

However, they did not give the numerical method for computing the homogenization parameters and solve the homogenization equation.

然而，他们没有给出计算均匀化参数和解均匀化方程的数值方法。

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。