查询词典 invariant subspace

The whole state space is divided into invariant subspace, safe subspace, dangerous subspace and dead subspace according to the constraints and the safe margin of the system, and the state reference trajectory is chosen with respect to the subspace in which the state prediction lies in, in this way GPC is applied under the prerequisite for the viability of the system.

研究了系统在线性不等式约束条件下的预测控制问题，将广义预测控制算法化为对控制量的一步优化，根据约束条件和输出预测在线修改控制量的加权系数，提出了一种变加权系数的改进算法，使系统始终满足给定的约束条件。

At first, some properties in the sampling subspace are classified. Then, that the subspace spanned by the translation of a function is also a subspace is proved in the shift invariant subspace.

首先通过Zak变换刻画了抽样空间的一些性质，然后证明了在一个平移不变的抽样空间中，由其中任一个函数的整平移所张成的子空间也是抽样空间。

In chapter 2, first of all,we characterize subspace V_0 of multiresultion analysis {V_j}_~ based on invariant subspace. Subsequently, we consider the equivalent conditions among orthogonal multiwavelet Ψ=(Ψ_1,Ψ_2,...Ψ_r)~T, subspace, basis and dimension of subspace, properties of filter function matrix P are dealt with.

第二章讨论了多尺度分析{V_j}_~中子空间V_0的性质，进而讨论了多尺度分析生成的多重正交小波Ψ=(ψ_1，ψ_2，…，ψ_r)~T和子空间V_0以及基和维数之间的等价关系，分析了滤子函数矩阵P的性质，最后给出了r阶矩阵函数P生成尺度函数Φ的充分条件。

Equivalently, it can be raised as follows: for an A operator T, if M and N are two invariant subspaces of T satisfying N include M and dimN/M=∞, then does there exist another invariant subspace L such that N include L, and L include M ? It is rather difficult to study the invariant subspace problem of general diagonal operators.

研究表明它可以约化为对角算子的不变子空间的情形，具体地它有如下的等价提法：对于A算子算T，，如果M和N是T的两个不变子空间，满足且dimN/M=∞，那么是否存在T的另一个不变子空间L使得M包含于L，且L包含于N？

This thesis mainly discuss following issues, Theory and simple expressions for array covariance matrixes are derived when angular spread functions are symmetric distribution functions, i. e. the Uniform distribution, the Gauss distribution, the Laplace distribution and the Von Mises distribution, and a non-symmetric distribution function, i. e. the Gamma distribution. And the relation between the effective signal subspace and the array number, or and the nominal angle of the distributed source, the angular spread, the distributed functions, and the Signal-to-Noise Ratio is gained. The dimension of the effective signal subspace increases with increment of the array number. And it is more obvious to the non-symmetric distribution. The dimension of the effective signal subspace decreases with increment of the nominal angle. And the distributed source is equal to a point source as θ=π/2. The dimension of the effective signal subspace increases with increment of the angular spread.

本论文针对阵列信号处理中广泛存在的分布源现象，主要讨论了以下问题：推导了角度分布函数分别为对称的均匀分布、高斯分布、拉普拉斯分布、Von Mises分布和非对称的伽马分布时，分布源阵列接收信号协方差阵的严格模型和简化模型，得到了单个分布源的有效信号子空间随阵元数、分布源中心角、分布角、角度分布函数和信噪比的变化规律：随着阵元数的增加，对所有角度分布函数的有效信号子空间维数也随着增加，且非对称分布函数的有效信号子空间充满整个空间的可能性更大；随着分布源中心角逐步增加，有效信号子空间维数逐步减小，当θ=π/2时，等价于点源情形；随着分布源分布角逐渐加大，有效信号子空间维数也随之增加，直到有效信号子空间充满整个空间；随着信噪比的增加，有效信号子空间维数有一定程度的减少。

In order to make the new recursive method convergence fast, the RLS-like forgetting factor is introduced to construct the new data Hankel matrices. In the framework of subspace methods, the gradient type subspace tracking method is used to implement the update of the state subspace, which results the unbiased estimate. Different from traditional offline method, the system matrices are recursively computed using RLS method. The convergence analysis of the proposed method is given and finally, the efficiency of this method is illustrated with a simulation example.A new closed-loop identification method is proposed to implement consistency estimation of closed-loop subspace identification.

引入RLS-like遗忘因子机制构造新的数据矩阵，更好地跟踪系统时变信息，提高递推算法的收敛速度；在子空间辨识框架内，采用梯度型子空间跟踪算法实现对状态子空间的更新，避免了子空间近似带来的估计有偏性；与传统的离线算法不同，在得到系统状态子空间后，基于递推最小二乘方法提出新的算法，实现对系统矩阵的递推估计；并给出递推子空间辨识算法的收敛性分析；最后通过仿真实例验证算法的有效性。

The well-known invariant subspace problem is A long-standing problem in operator theory,which has been to determine whether every operator $T$ on a Banach space $X$ must have a nontrivial invariant subspace.

不变子空间问题是一个尚未解决的问题， Enflo反例所给出的没有不变子空间的算子不为任何算子的共轭。

Secondly, the concept of column space, cyclic invariant subspace and generalized cyclic invariant subspace were introduced.And some basic properties, such as separation lemma, were presented.

其次，引入列空间、循环不变子空间和广义循环不变子空间等基本几何概念，给出一些有关概念的基本性质，特别是分离引理。

An iterative factorization method based on linear subspace for projective reconstruction is presented in the paper. It relies on the facts that the rows in the matrix including all the image points span the same linear subspace as the rows in the matrix including space points and the fact that any basis of the subspace can be regarded as projective reconstruction. The projective reconstruction and the depth factors are obtained based on linear iteration.

摘要该文提出了一种基于子空间线性迭代的射影重建方法，该方法利用所有的图像序列构成的行向量生成的线性子空间之和与射影重建结构点构成的行向量生成的子空间是同一线性子空间及在该子空间中任何一个基底都可以作为射影重建的特性，线性迭代地求取射影重建及图像深度因子。

The former uses Eigen-associative Learning algorithm to learn various facial expressions according to a face image with neutral expression. The latter is a two-level fusion approach which combines local linear and global nonlinear subspace learning. Amongst, the local linear subspace learning adopts eigen-representation technique for video sample compression in temporal domain; the global nonlinear subspace learning synthesizes optimized facial expressions in spatial domain.

前者采用特征关联学习算法根据一幅中性表情人脸图像合成具有其它表情的人脸图像；后者是一种结合局部线性和全局非线性子空间分析的两层融合方法，其中局部线性子空间学习采用特征表示技术在时间域对视频样本进行压缩、全局非线性子空间学习在空间域内产生优化的人脸表情。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。