对称

This paper illustrates the process where projective transformation and affine transformation are employed to solve advanced geometrical problems.

引言变换是我们在几何解题中常用的方法之一。初等几何中的变换方法有对称变换、平移变换、旋转变换和相似变换，高等几何中的变换有射影变换、仿射变换等。

It consists of the next three aspects: firstly, we study Murthys' open problem whether the augmented matrix is a Q0-matrix for an arbitary square matrix A , provide an affirmable answer to this problem , obtain the augmented matrix of a sufficient matrix is a sufficient matrix and prove the Graves algorithm can be used to solve linear complementarity problem with bisymmetry Po-matrices; Secondly, we study Murthys' conjecture about positive semidefinite matrices and provide some sufficient conditions such that a matrix is a positive semidefinite matrix, we also study Pang's conjecture , obtain two conditions when R0-matrices and Q-matrices are equivelent and some properties about E0 ∩ Q-matrices; Lastly, we give a counterexample to prove Danao's conjecture that if A is a Po-matrix, A ∈ E' A ∈ P1* is false, point out some mistakes of Murthys in [20] , obtain when n = 2 or 3, A ∈ E' A ∈ P1*, i.e.

本文分为三个部分，主要研究了线性互补问题的几个相关的公开问题以及猜想：(1)研究了Murthy等在[2]中提出的公开问题，即对任意的矩阵A，其扩充矩阵是否为Q_0-矩阵，给出了肯定的回答，得到充分矩阵的扩充矩阵是充分矩阵，并讨论了Graves算法，证明了若A是双对称的P_0-矩阵时，LCP可由Graves算法给出；(2)研究了Murthy等在[6]中提出关于半正定矩阵的猜想，给出了半正定矩阵的一些充分条件，并研究了Pang~-猜想，得到了只R_0-矩阵与Q-矩阵的二个等价条件，以及E_0∩Q-矩阵的一些性质；(3)研究了Danao在[25]中提出的Danao猜想，即，若A为P_0-矩阵，则，我们给出了反例证明了此猜想当n≥4时不成立，指出了Murthy等在[20]中的一些错误，得到n=2，3时，即[25]中定理3.2中A∈P_0的条件可以去掉。

The simulation shows that STFMPC signal is sensitive to Doppler frequency-shift,and its ambiguity function has one aiguille at the origin and four symmetrical right-angle set-squares with the aiguille as their common spindle.

通过计算机仿真，结果表明该信号是多普勒敏感信号，其模糊函数为在原点的1个尖峰和4个以尖峰为公共轴的有一定厚度的对称直角三角板。

Calculating method of air damping and its influence on operation characteristics is discussed.

在此基础上提出了一种新型的对称解耦微机械陀螺结构。

The non-continuously moving state lies on the vehicle's structural characteristic. This air-cushion vehicle has two platforms, which are connected by two hydraulic cylinders. When it moves, one platform is fixed on ground as the base platform, and takes the other one as moving platform, then the vehicle can go forward by alternate movement of these two platforms. So the push-pull air-cushion vehicle is a self-propelled vehicle.

它的非连续运动形态取决于其结构特点，该气垫车由两个对称的子平台组成，中间通过液压油缸相铰接，运动时总是固定其中一个平台作为基础平台，而将另一个平台作为运动平台，基础平台通过液压缸推出或拉进运动平台交替动作，实现运动，因此推拉式气垫车是一种自走式气垫车。

At baseline and on day 1, 3, 7, 14, 21 following MPP+ injection, the degree of microglial activation was examined by detecting the immunodensity of OX-42 in the substantia nigra. The number of viable dopaminergic neurons was determined by measuring tyrosine hydroxylase positive neurons in the SN. Behavioral performances were evaluated by counting the number of rotations induced by apomorphine, calculating scores of forelimb akinesia and vibrissae-elicited forelimb placing asymmetry.

分别在基线、MPP+注射后第1、3、7、14、21天时通过测定黑质区域OX-42的免疫荧光强度评定小胶质细胞的激活程度，测定酪氨酸羟化酶的表达情况评定存活多巴胺神经元的数量；通过阿朴吗啡诱导的旋转行为、前肢跨步及触须引发的不对称放置试验得分测评行为学表现。

For example, using chiral tungsten 2'-pyridinyl alcoholate complex at 50 ℃, the ee value was increased from 54% to 78%.

在磷霉素的不对称合成研究方面只有Giordano等[4]是以顺丙烯膦酸为起始原料进行的。

The asymmetric aldol reaction is one of the most important methods of forming carbon-carbon bonds.

不对称羟醛缩合反应是有机合成中立体选择性地形成碳碳键的最重要方法之一。

Its zinc complex was applied in asymmetric direct aldol reaction of acetone and p-nitrobenzal...

设计合成了一种NOBIN衍生的手性配体，初步研究了该手性配体的双核锌配合物在对硝基苯甲醛和丙酮的不对称直接醇醛缩合反应中的催化应用，20℃和20mol％催化剂量下，获得了32.5％ee和72％收率的产物。

Synthesis of novel 4-long alkoxyl-L-prolines and their application in catalytic asymmetric direct aldol reaction.

一、研究了新型长链烷基脯氨酸的合成及其作为有机小分子催化剂催化的直接不对称Aldol反应 1。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。