查询词典 generated subspace

Finally, a basic lemma was given to reveal the relation between the solution set of a centain integral equations and the generalized cyclic invariant subspace. This lemma will play an important role in the determination of controllability.

然后以一个基本引理的形式揭式某一积分方程的解集与广义循环不变子空间之间的联系，这个引理将在能控性的判定中起关键作用。

Classification of two-component nonlinear cross-diffusion systemsis presented by a developing invariant subspace method.

将不变子空间方法进行推广，并用于带有交错扩散项的非线性方程组的分类。

Firstly, the recent developments in controllability and observability for switched system are reviewed. Secondly, by means of properties of invariant subspace, the controllability for switched systems with continuous-time and discrete-time subsystems, and a class of discrete impulsive switched systems is respectively investigated. Some sufficient and necessary conditions of controllability are proved. In the end, some simple criterions for controllability and observability of switched symmetric composite systems are set up.

首先介绍了切换系统能控性与能观性方面的一些重要结论；其次，用不变子空间的性质分别研究了同时含有连续子系统和离散子系统的切换系统和一类离散脉冲切换系统的能控性，建立了相应的充分性与必要性判别准则；最后，研究了切换对称组合系统的能控性与能观性，得到了此系统能控性与能观性的简单判据。

In order to investigate the variation of controllability and observability affected by network scheduling,the model of scheduling for Networked Control System is established,which has communication constraint on its input and output channel.Utilizing communication sequence to express the scheduling of channel,the model can be transformed into discrete-time switch system.Under static scheduling,using the theory of recursive invariant subspace and its character,a necessary and sufficient condition of NC...

为了研究网络调度对能控性与能观性的影响，对输入、输出通道都存在通信约束的网络控制系统的调度进行建模；利用通信序列表示通道的调度情况，最终将模型转化为离散切换系统；在静态调度下，利用循环不变子空间理论及其相关的性质，给出了网络控制系统能控性、能观性成立的充要条件，并给出了原有控制系统与经网络静态调度后的系统之间能控性、能观性的关系；最后用仿真实例说明了所提结论的正确性。

Thin film equations; nonlinear cross-diffusion systems; two-dimensional nonlinear reaction-diffusion equations; invariant subspace method; invariant sets

基础科学，数学，数学分析薄膜方程；非线性交错扩散方程组；二维非线性反应扩散方程；不变子空间方法；不变集

It is proved that every Lie derivation of nest algebra is the sum of an associative derivation and a general trace. Every Lie isomorphism between nest subalgebras of a factor von Neumann algebra is the sum of an isomorphism and a general trace or the sum of a negative anti-isomorphism and a general trace. Lie invariant subspace of linear mappings on Banach algebras is introduced, and linear maps from nest subalgebra of a factor von Neumann algebra into itself which satisfy the property that the space of derivations is their Lie invariant subspaces are characterized. Simultaneously, it is shown that such maps are Lie derivations modulo the set of scalar multiple of the identity.

得到Lie导子的特征表示，即套代数上的任何一个Lie导子都是内导子与广义迹之和；给出了Lie同构和同构及反同构之间的关系，即因子von Neumann代数中套子代数之间的任何一个Lie同构要么是同构与广义迹之和要么是负反同构与广义迹之和；引入了Banach代数上线性映射的Lie不变子空间，并给出von Neumann代数中套子代数上以导子空间为Lie不变子空间的线性映射的一个刻画，同时也表明在模去数乘恒等映射的意义下，以导子空间为Lie不变子空间的线性映射就是Lie导子。

The key points of DGA is to start evolution with initial population evenly distributed in searching space to avoid the leakiness of subspace, to accelerate the searching process by directed crossover and mutation, to improve holistic survival and adaptive ability by means of competition and parallel evolution in genetic system. However, the crossover and mutation act on different lays in space made the searching uniform.

其基本思路是以空间上均匀分布的初始点展开演化以避免子空间的遗漏，以有方向性的杂交和变异加速和调节搜索，同时杂交和变异作用在不同层面上使搜索在整体上均匀化，通过遗传系统里的并行竞争提高整个群体的生存适应力，从而达到整体优化的目的。

An incremental-iterative method based on the Newton-Raphson method combined with constant arc length of incremental displacement vector is employed for the solution of nonlinear equilibrium equations. The subspace iterative method is used for the solution of natural frequencies and vibration modes for the free vibration of beam structures.

本研究推导元素的节点惯性力时，先将元素扰动位移表示成当前固定元素座标的扰动位移和旋转之函数，故可直接求得元素的节点惯性力，元素的一致性质量矩阵可由元素节点的惯性力对元素节点的加速度微分求得。

The classic iterative ones need special characters of the coefficient matrix; CG has over linear convergence, but the coefficient matrix is positive definite; Krylov subspace ones can deal with non-symmetric linear systems, but sometimes it must face"collapse"problems.

经典迭代法的收敛需要由系数矩阵的一些特定性质来保证；共轭梯度法具有超线性收敛性，但是系数矩阵必须是正定矩阵；Krvlov子空间法可用于非对称矩阵问题，但可能出现崩溃现象。

The cyclic subspace regression analysis was studied from the viewpoint of linear functional.

从线性泛函的角度分析循环子空间回归方法。

Diabetes is a social disease that affects several million people worldwide.

糖尿病是一个社会性疾病，全世界有数百万人罹患此病。

I'll call you on Friday to see if we can reschedule our luncheon meeting at your convenience.

我星期五会给您打电话在您方便的时候我们重新安排我们的午餐约会。