查询词典 stable manifold

The definitions of generalized directional derivative and generalized gradient of Lipschitz functions defined on Riemannian manifold are presented. Some properties of the directional derivative and gradient are proved by using tangent and cotangent mapping. The minimization necessary condition of nonsmooth Lipschitz functions is given. Moreover, Fritz John necessary optimality condition in mathematical programming is provided on Riemannian manifold.

在黎曼流形上给出了Lipschitz函数的广义方向导数和广义梯度的概念，利用黎曼流形局部上与欧氏空间开集微分同胚的性质以及切映射和余切映射导出了广义梯度的性质和运算法则，证明了定义在黎曼流形上的函数取得极小值的必要条件是广义梯度包含零元素，并利用这些性质给出了黎曼流形上数学规划问题的Fritz John型最优性条件。

Construct the three-dimensional manifold element covering hexahedron, provide cover displacement function, strain matrix, stiffness matrix and stress matrix of the three-dimensional manifold element by the previous research work.

6在前人研究的基础上，构造了六面体有限覆盖的三维流形单元，推导了三维流形单元覆盖位移函数、应变矩阵、刚度矩阵、荷载矩阵等表达式。

The velocity hydrophone array manifold can also be divided into two subarray manifolds,which constitute a rotation pair with the pressure hydrophone array manifold,and the rotational invariant factors comprise the source's other direction cosine.

振速水听器阵可以被划分为2个子阵，它与声压水听器阵构成旋转对，旋转因子为另一轴方向余弦。

The first part presents develops of predator-prey systems and gives the model that is investigated in our paper; Chapter 2 presents the results on boundedness of solutions and permanence of system; In chapter 3, we explicitly derive a domain of attraction for the positive equilibrium of system by using Liapunov method; The local stability and the conditions that Hopf bifurcation occurs are obtained in chapter 4; In chapter 5, some explicit fomulae of the direction of Hopf bifurcation and the stability of bifurcating periodic solutions on the center manifold are determined,using normal form and center manifold introduced by Hassard et al; In chapter 6, some numerical simulations are performed to illustrate the analytical results found; Our paper ends with a brief conclusion.

全文共分七章，第1章对捕食-食饵系统的发展背景做了介绍并给出了本文研究的模型；第2章讨论了系统的保持性和解的有界性；第3章研究正平衡点的全局性质，对正平衡点的吸引域进行了精确估计；第4章研究了系统的正平衡点的局部稳定性和Hopf分支存在的条件；第5章利用规范型和中心流形定理得到了一个决定Hopf分支方向、分支周期解的稳定性及其他性质的精确公式；第6章对一个具体模型进行了数值模拟；第7章对全文进行了总结。

Based on a series of signal process and noise source identification techniques, especially the major noise source identification methods, such as expurgation method, sound intensity analysis, spectrum analysis vibro-acoustic correlation analysis and so on, the pass-by noise control of SC7080A and SC6360B are studied in detail. By the roadway and dais experiments, the major noise and radiating parts are identified and some economical controlling methods are made. For the SC7080A, to control the emissing noise from the intake and shell vibration of air cleaner, a intake muffler is installed between the air cleaner and intake valve. Based on the theory of Helmholtz resonator, One three-parallel-connected resonant silencer is designed and trial-manufactured. For the SC6360B, the attenuation performance of exhaust muffler in high frequency region is improved. To reduce the vibration noise of shell part, the structure of oil sump tank, exhaust manifold shield and exhaust manifold shield are analyzed and improved. At the same time, some measures, such as sound absorption, sound insulation, are taken to reduce the noise of engine surface emissivity and a sound shield is designed.

本文首先综述了目前国内外汽车加速噪声控制的现状、主要方法和技术措施，在此基础上，结合SC7080A和SC6350B汽车的车外加速噪声水平及现状，综合运用分别运行法、声强法、频谱分析法、声振相干函数法等现代噪声源识别方法，对SC7080A和SC6360B汽车进行了准确详细的车外加速噪声源识别并提出了经济可行的控制方案，针对SC7080A，主要在空气滤清器和进气阀门之间的进气管道上加装进气消声器，抑制空气滤清器壳体表面和进气口两处的噪声辐射，根据Helmholtz共振腔原理设计了三腔并联旁支型共振消声器，并进行了工程化设计和试制；针对SC6360B，主要改善了排气消声器在高频段的消声性能，对罩壳类零件进行了结构改进，降低了其表面噪声的辐射，并对发动机舱进行了吸声、隔声处理，设计了发动机隔声罩。

Using numerical simulation technology and method of orthogonal experiment design and single factor rotating optimization, this thesis makes a study of "lost core injection ", thus achieve the optimization of the parameters of molding process, to offer basic reference when developing production technology and mould of the plastics intake manifold. Based on the study of the status in quo and development trend of weight reduction on automobile, the application of plastics to automobile and intake manifold, then under the guidance of theory model and numerical simulation technology in the process of high polymer material, this thesis launches flowing main research work: First of all, on the basis of the three-dimensional model of the part and finite element net model, several designs of gating and running system are numerically simulated and analyzed via MPA of Moldflow.

本文在对当今汽车轻量化、零部件塑料化以及的汽车进气歧管塑料化的发展现状和发展趋势进行了研究和简要介绍，然后在高分子材料成型过程中的理论模型和数值计算方法的指导下，展开主要的研究工作：首先，在零件三维模型和有限元网格模型的基础上，使用Moldflow 的MPA模块对塑料进气歧管的多个浇注系统设计方案进行数值模拟，通过分析各个方案的充填质量、熔接线位置及数量等指标，得到了综合质量较高的4 个进料口的浇口位置及半限制型浇口大小的浇注系统。

In this study,a novel artificial immune system algorithm for unsupervised classification and recognition is proposed by using a novel manifold distance based dissimilarity measure which can measure the geodesic distance along the manifold.

将一种新的流形距离作为相似性度量测度，提出了一种用于无监督分类与识别的人工免疫系统方法。

In this study, a novel artificial immune system algorithm for unsupervised classification and recognition is proposed by using a novel manifold distance based dissimilarity measure which can measure the geodesic distance along the manifold.

摘要将一种新的流形距离作为相似性度量测度，提出了一种用于无监督分类与识别的人工免疫系统方法。通过基于流形距离的相似性度量，有效利用样本集固有的全局一致性信息，充分挖掘无类属样本的空间分布信息，对样本进行类别划分。

One important feature ofHamiltonian systems is that it has energy(its energic function is Hamiltonian func-tion),then,its solutions on 2-dimensional plane are some contour lines,the points onstable manifold emanating from hyperbolic equilibrium point have the same energyas that on unstable manifold,then,one can guess that they form a closed curve,i.e.homoclinic orbits under certain conditions,and the contour lines in the innerpart of homoclinic orbit are periodic orbits.

哈氏系统的一个重要特征是它有能量存在(以Hamiltonian函数作为它的能量)，那么在二维平面上，它的解表现为一些等值线，从双曲平衡点发出的稳定流形和不稳定流形上的点具有相同的能量，那么可以猜测，在一定条件下它们构成一条封闭的曲线，即同宿轨，而且其内部的等值线都是周期轨道。

Another definition of linear manifold is given, some properties of linear manifold as well as its relationship with linear space and system of linear equations are obtained.

本文从线性流形另一定义出发，得到线性流形的有关性质，并指出其与线性空间以及线性方程组之间的关系。

The shaping method of noncircular part and the tool holder's radial motion characters in noncircular turning process are discussed in detail in the thesis.

论文详细研究了非圆零件的成型方法和加工过程中刀架的径向运动规律。

I have not really liked him,I do not like his this kind of disposition.

我没有真的喜欢他，我不喜欢他的这种性格。