查询词典 boundary

Boundary features are the boundary lines of a group of points distributed on a fitting feature.

边界特徵之萃取理论是利用拟合特徵所给予之资讯，找出属於边界之点云资料，再由这些边界点云资料计算出边界特徵。

The total transmission ratio, the relationship between basic transmission ratio and closed transmission ratio and their influences on efficiency were studied on the H typed closed epicyclic train, and the expression of boundary region of basic transmission ratio under conditions of satisfying the allowable efficiency was gained and the boundary curve was drawn.

研究了H封闭式周转轮系总传动比、基础传动比与封闭传动比之间的关系及其对效率的影响，得到了在满足许用效率的条件下基础传动比边界区域表达式，绘出了边界曲线。

The improved e-N method can also yield results well agree with those obtained by DNS.4 The transition prediction for boundary layers on cones with different key parameters such as angle of attack, cone half angle and the Mach number of the coming flow, have been made, to show the reliability of the modified e-N method.5 For the calculation of base flow, boundary layer equations can be used in the case of small angle of attack.

但是它要依赖于对初始扰动的正确预估，这显然又取决于更多飞行数据的积累和分析。e-N方法的转捩预测结果与直接数值模拟得到的结果也吻合较好。4通过对不同来流攻角、不同半锥角和不同马赫数的三维圆锥边界层的转捩位置进行预测，证实了改进的e-N方法对于三维边界层转捩预测是可靠的。5对于基本流的计算，边界层方程可以用于小攻角的情况，其计算量远远小于直接数值模拟，但背风面的剖面不可靠。

The second chapter is the main part of this paper, in which the formulation of the Riemann boundary value problem of non-normal type on the real axis, the solution method of homogeneous problem, the relation between the two kinds of different derivatives and the inhomogeneous problem will be thoroughly given. In this paper, the solution and the solvability of the Riemann boundary value problem of non-normal type on the real axis will be given. Furthermore, it is shown that the twokinds of derivatives of the function Ψ are existing and equivalent in the case ofthe solution about the original problem, therefore, we get uniformly Hermite interpolatory polynomial. The relation between the two kinds of different derivativesof the function Ψ are similar for smooth closed contours by means of the same proof.

第二章是本文的主要部分，分别给出了实轴上一类非正则型Riemann边值问题的提法、齐次问题的解法、两种导数的关系及非齐次问题的求解，本文运用杜金元教授[11]的方法获得了实轴上非正则型Riemann边值问题的封闭解及可解性条件，且在问题可解的情况下论证了函数Ψ的非切向极限导数和Peano导数存在且相等，从而获得了统一的Hermite插值多项式，同样关于封闭曲线上非正则型Riemann边值问题，采用本文论证方法证得了函数Ψ的非切向极限导数和Peano导数存在且相等，从而较好地统一了[10]、[11]中的Hermite插值多项式。

According to the studied results at present, the studied objects are mainly thin plate and beam about sound radiation mode, a method computed sound radiation mode of complex structure is presented in this dissertation, according to the results of the previous two chapter, a theoretical method to solve acoustical radiation mode and acoustical radiation efficiency of complex structure by boundary element method and acoustical radiation theory is posed, the acoustical radiation power is expressed as a Hermitian quadratic form, while the radiation modes is determined by general eigenvalue decomposing, and then the radiation efficiency is computed via the orthodoxy of radiation modes with regard to impedance matrix and average velocity matrix; lastly, the validity of the method is proved by pulsating sphere and radiating cube with analytical results. According to results of the form three chapter, the structure sound radiation sensitivity is studied in detail, the sound radiation power of structure can be expressed as positive Hermitian quadratic form, the sound radiation sensitivity can be expressed as two parts by partial differential with respect to design variable, which are sensitivity of boundary velocity and impedance matrix, combined with the theory of FEM and BEM, the structure sound radiation can be translated to the analysis of structure dynamic sensitivity and impedance matrix sensitivity. The theory posted in this dissertation is tested by the FEM software ANSYS and the software AAS programmed by author.

在前几章的基础上，通过结构声辐射的模态理论对结构的声辐射的机理进行了深入地探讨，针对目前声辐射模态的研究对象主要是简单的板和梁类结构，提出了一种计算复杂结构声辐射模态的方法，利用前两章研究所得的结论，将边界元方法与广义特征值的理论结合起来研究了复杂结构的声辐射模态与声辐射效率，先将结构的声辐射功率表示为一个正定的厄米特二(来源：ABb7C论文0909网www.abclunwen.com)次型，运用广义特征值分解求解了复杂结构的声辐射模态，然后利用声辐射模态关于阻抗矩阵与均方速度耦合矩阵的正交性，求解了复杂结构的声辐射效率，最后用具有解析解的脉动球与辐射立方体验证了该方法的有效性。

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。

Nonlinear Riemann boundary value problems and nonlinear Hilbert boundary value problems will be studied in this paper, because they have been researched seldom.

对于非线性的Riemann边值问题和非线性的Hilbert边值问题研究很少，本文试图在这些方面做一些工作。

By using them, we can discuss the theory of holomorphic functions on domains: the characterization of zeros sets of holomorphic functions on the boundary, the characterization of A infinity interpolation sets on the boundary, etc.

对于复椭球和广义复椭球，我们给出了其全纯支撑函数的估计，构造了边界上的拟距离，并用这些结果来研究域上的解析函数论：边界上解析函数零点集的刻划，A无穷插值集的刻划等。

There is a relatively complete style of homogeneous function about the boundary condition in the problem of sure resolution of unhomogeneous boundary condition,which is based on the summarizing of mass former experiences and is proved in this article.

通过对非齐次边界条件的定解问题的讨论，引出了本文的论题，对非齐次边界条件定解问题的边界条件齐次化函数提出了一种比较一般和标准的形式，并提出了一个定理。对该定理进行了证明，证明了它的正确性。

We consider the existence of positive solutions of second order impulsive boundary value problems by constructing the appropriate homotopy operator and applying the theory of fixed point index in cones. our results contain the conclusion when f ≥ 0 and J_k = 0([6]). Secondly, we discuss multiple positive solutions of the following impulsive boundary

其次，我们在§2.2中讨论了下面的脉冲微分边值问题多正解的存在性在这一部分的讨论中，利用不动点指数理论，在f既非超线性又非次线性的情形下，得到了两个正解的存在性定理，把文[7]的结果推广到脉冲微分边值

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。