查询词典 symmetric difference

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。

First the related condition which causes the non symmetric thrust flight and the control method under the circumstances of the non symmetric thrust flight are stated, the relationship between the non symmetric thrust flight and the minimum control speed is pointed out.

首先 ，叙述了发生不对称推力飞行的条件，在不对称推力飞行条件下的操纵方法，以及和最小操纵速度的关系。

This chapter clarifies the nested relationship between the matrix family of unitary, orthogonal, Givens, Householder, permutation, and row or column symmetric matrices. A precise correspondence of the singular values and singular vectors between the unitary-symmetric matrix and its mother matrix is derived and proved (hence a fast algorithm of singular value decomposition for unitary-symmetric matrix is straightforwardly obtained), and the corresponding perturbation bound is provided.

该章揭示了酉对称矩阵、正交对称矩阵、 Givens 对称矩阵、 Householder 对称矩阵、置换对称矩阵和行对称矩阵之间的逐级包含关系；推导并证明了，酉对称矩阵的奇异值和奇异向量与母矩阵的奇异值和奇异向量之间的定量关系，据此可得酉对称矩阵奇异值分解的快速算法；给出并证明了摄动矩阵的摄动界。

Sign symmetric matrix;anti sign symmetric matrix;weakly sign symmetric matrix;spectral property

符号对称矩阵；反符号对称矩阵；弱符号对称矩阵；特征值

The symmetric algorithm is a traditional algorithm, it is easy and efficient, and so it is still being popular used. The stream cIPher and the block cIPher are two part of the symmetric algorithm. The symmetric algorithm uses the key to control the key stream generator, and then the generator produces a random stream. We can get the cIPher by xor the message and the random stream by bit. In the field of communication and code, the stream cIPher has always been the key cIPher of the military affairs and foreign affairs.

对称密码体制分为序列密码和分组密码两类，序列密码以密钥控制密钥流发生器，产生一随机序列，用这个随机序列和明文信息逐位异或，就得到密文，其加密单元为比特。

Based on the new systematic classifications of S-O positional exchange in Chinese simple sentences, this paper, from the perspective of symmetric relation of mutuality, proposes a new explanation of semantic symmetry that the subject and object in SVO structure can be exchanged if they are two things which are semantically symmetric and the common semantic element in such sentences is the mutually symmetric semantic relation.

相互关系是一种对称性关系，从这个角度入手，主宾可互易的存现句、某些表心理感知类语义的以及表分配类的句子都可纳入相互关系义句，这样主宾互易现象从相互关系这种对称性语义关系角度就有了新的解释－语义上具有对称性关系的两个事物表现在主动宾结构中的主宾位置是可以互易的，这些主宾互易句里的共同语义因素就是相互对称性关系语义。

Tridiagonalization of symmetric matrices and computing eigenvalues of tridiagonal symmetric matrix are the keys of eigenproblem parallel solver of dense symmetric matrix.

对称矩阵三对角化和三对角对称矩阵的特征值求解是稠密对称矩阵特征问题并行求解器的关键步。

Based on definition of orthogonal counterbalance, authors definite the unitary counterbalance of matrix and prove the unitary counterbalance properties of unitary symmetric matrix and it s mother matrix, obtain some results as the Moore-Penrose inverses of unitary symmetric matrices are unitary counterbalance if unitary symmetric matrices are unitary counterbalance .

从矩阵正交相抵的概念出发，给出了矩阵酉相抵的概念，证明了酉对称矩阵与母矩阵之间的酉相抵性，得到了酉相抵矩阵的Moore Penrose逆等一些新的结论。

According as the four modes in a symmetric waveguide, that one of modes is symmetric or anti-symmetric about X axes or Y axes, are X polarized or Y polarized odd mode or even mode, we calculated the polarized coupling characteristics using Cassinian curves as boundaries of the couplers.

本文还根据对称波导中对称于或反对称于x轴或y轴的四个模式分别为x偏振或y偏振的奇模或偶模的原理，用Cassinian曲线表示耦合器介质波导的边界，计算了耦合器的偏振耦合特性。

Results On CT,of 8 cases.Symmetric hypodense areas of bilaleral thalami and internal capsules were fund in 7 cases.symmetric hypodese areas of bilateral basal gangalia were simutaneosly seen in 5 cases.On MRI,of 5 cases,symmetric Long-T1 and long-T2 signals of bilaleral thalami,internal capsules and basal ganglias were fund in all cases;Thrombi were seen in vein of Galen and oringinal of straight sinus in 5 cases in a period of 3～11 day after the disease came on.It were displyed hyperdensity on CT and short-T1 and long-T2 signals on MRI and disppeared in a period of 14～30 days after the diseases came on.

结果 CT表现为双丘脑、双内囊对称性低密度影7例，同时并有双基底节对称性低密度影5例，MRI表现为双丘脑、双内囊及双基底节区对称性长T1、长T2异常信号5例；5例发病后3～11天内于Galen静脉及直窦起始部可见栓子，CT表现为高密度，MR表现为短T1、长T2异常信号，14天后检查栓子消失。

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。