角锥后向反射器的数值模拟研究

鉴于实际应用的需要，考虑角锥反射器的二面角加工误差，采用矩阵光学和矢量运算方法，建立了一套适合于数值模拟的角锥反射器的后向反射数学模型，给出了角锥后向反射器光束变换及衍射传输的公式和数值模拟计算方法。分别针对理想角锥后向反射器和有二面角加工误差的角锥反射器，研究了反射光束的传输特性，分桥了入射角和传输距离对近场和远场能量分布的影响。根据卫星搭载角锥反射器的特殊要求，讨论了速差补偿方法和设计等问题，并针对卫星姿态控制的两种情况，分别提出了速差补偿的设计方案。     

On Orthogonal Latin <Emphasis Type="Italic">p</Emphasis>-Dimensional Cubes

We give a construction of p orthogonal Latin p-dimensional cubes (or Latin hypercubes) of order n for every natural number n ≠ 2, 6 and p ≥ 2. Our result generalizes the well known result about orthogonal Latin squares published in 1960 by R. C. Bose, S. S. Shikhande and E. T. Parker.     

三维随机SIERPINSKI地毯的相位和临界概率

本文用概率论的基本方法结合矩阵表示上的置换方法，证明了三维随机 Ｓｉｅｒｐｉｎｓｋｉ地毯随着保留概率从０到１变化，过程组态经历几个不同的相位，并求出各相位间的临界概率或给出其范围．     

风电场地形绕流的CFD结果确认研究

掌握复杂地形区域的风能分布对风电场微观选址至关重要.为把CFD技术应用于风场中实际地形的风流动模拟,本文选择三种具有实验数据的典型地形进行数值计算,并对数值结果进行确认研究.文中简述了不同网格和不同湍流模型对旋涡位置和速度分布的影响,并探讨了为增加风能利用率,如何确定风力机的最佳安装位置.     

角锥棱镜腔Nd:YAG/Cr4+:YAG被动锁模激光器的研究

理论分析并数值模拟了腔内光强随角锥棱镜旋转的变化,实验证明在角锥棱镜腔Nd:YAG/Cr4 :YAG被动锁模激光器中,偏振耦合输出得到了锁模深度和锁模几率近乎100%的线偏振被动锁模脉冲输出.通过旋转角锥棱镜改变偏振耦合输出、调节腔内光强,可以得到被动锁模和被动调Q两种状态的脉冲输出,脉冲能量166.5 mJ/pulse,脉冲动静比高达59.7%.     

锥体棱镜的加工与检验

锥体棱镜是一种重要的逆向反射器 ,它广泛应用于远距离测距等方面。同时也是一种精度高、加工难度大的光学元件。介绍了锥体棱镜的两种加工工艺及其特点 ;着重叙述了立方体切角的方法 ,即借助于 T型抛光定位夹具和切角定位夹具加工锥体棱镜的工艺过程。同时给出了当用干涉法测量锥体棱镜时 ,干涉图的判别原则和棱镜合格时干涉图的特点。该方法对综合角度误差≤ 3″的锥体棱镜来说可获得很高的合格率。     

Electronic Structure and Photophysical Properties of 2-(N,N-diethylanilin-4-yl)-4,6-bis(3,5-dimethylpyrazol-1-yl)-1,3,5-triazine

Electronic structure and photophysical properties of 2-(N,N-diethylanilin-4-yl)-4,6-bis(3,5-dimethylpyrazol-1-yl)-1,3,5-triazine are studied theoretically with quantum chemical methods as well as 2D site and 3D cube representations. The theoretical results reveal that the first excited state is an intramolecular charge transfer excited state. The change in dipole moment for the first excited state of the excitation is fitted, and the calculated result the change in dipole moment ￠1=6.40 D is consistent with the experimental result ￠1=6.90 D. The polarizability is also fitted. The large changes in dipole moment and the polarizability of the excitation show that S1 is of large nonlinear optical (NLO) effect. The NLO will promote efficient two-photon-absorption cross sections. The excited state properties of dpbt with different external electronic fields are also discussed theoretically.     

Singular homology groups of fuzzy topological spaces

Let L be a completely distributive lattice with order reversing involution, and (X, τ) an L-fuzzy topological space. The purpose of this paper is to introduce the fundamental concept of fuzzy algebraic topology-the singular homology groups of the L-fuzzy topological space, in such a way that they take the (usual) cubical singular homology groups of a topological space as a special case. Also, we shall prove that they are L-fuzzy homeomorphic invariants.     

Lipschitz homeomorphisms of the Hilbert cube

We study the question whether the Hilbert cube Q is Lipschitz homogeneous. The answer depends on the metric of Q. For example, setting d(x,y)=sup_j|x_j-y_j|/j we obtain a Lipschitz homogeneous metric, but if the last j is replaced by j!, the answer is negative.     

Determination of msd(Ln)

The median stabilization degree (msd, for short) of a median algebra measures the largest possible number of steps needed to generate a subalgebra with an arbitrary set of generators. With computer assistance, we found that msd of the lattice {– 1, 0, 1 }4 equals 2. This value is of critical importance to determine msd of {– 1, 0, 1}n for all n 5 and to determine msd of the free median algebra (r) for almost all r 5.