双动点中的分类思想

分类是一种重要的数学思想方法,平面图形中双点运动时,常有某个元素不能确定,需作分类处理.     

简解一道美国数学月刊征解题

问题设x,y,z∈(0,+∞),且x2+y2+z2=1,求函数f=x+y+z-xyz的值域.这是一道美国数学月刊征解题,贵刊文[1]给出一个三角代换的解法,求解过程中还运用到导数的知识,运算繁杂难度较大,不易掌握.文[2]给出一个     

Design of phase plates for shaping partially coherent beams by simulated annealing

Taking the Gaussian Schell-model beam as a typical example of partially coherent beams, this paper applies the simulated annealing （SA） algorithm to the design of phase plates for shaping partially coherent beams. A flow diagram is presented to illustrate the procedure of phase optimization by the SA algorithm. Numerical examples demonstrate the advantages of the SA algorithm in shaping partially coherent beams. An uniform flat-topped beam profile with maximum reconstruction error RE 〈 1.74% is achieved. A further extension of the approach is discussed.     

部分线性模型中估计的收敛速度

考虑回归模型（Ⅰ）：其中（ｘ＿ｉ，ｔ＿ｉ）是固定非随机设计点列，ｘ＿ｉ＝（ｘ＿（ｉｌ），…，ｘ＿（ｉｐ））＇β＝（β＿１，…，β＿ｐ）＇（ｐ＞１），ｇ是定义在［０，１］上的未知函数，β是未知待估参数，０＜ｔ＿ｉ＜１，ｅ＿ｉ是ｉ．ｉ．ｄ．随机误差，且Ｅｅ＿ｉ＝０，Ｅｅ＝σ￣２＜∞。基于ｇ的估计取一类非参数权估计（包括常见的核估计和近邻估计），我们讨论了β的最小二乘估计及ｇ的估计的最优强弱收敛速度。     

N-乙基-1,10-菲罗啉-2-甲胺镍(Ⅱ)配合物的合成、晶体结构及性质研究

0IntroductionPhenanthrolinederivativescontainingaminegroupshavebothsoftandhardsitesandaregooddonorsformetalions.1,10鄄phenanthrolineanditsderivativeshavebeenextensivelyusedasligandsinbothanalyticalandpreparativecoordinationchemis鄄try[1].Mostoftheseworksh…     

On Weak Regular ^＊-semigroups

In this paper, a special kind of partial algebras called projective partial groupoids is defined.It is proved that the inverse image of all projections of a fundamental weak regular ^*-semigroup under the homomorphism induced by the maximum idempotent-separating congruence of a weak regular ^*-semigroup has a projective partial groupoid structure. Moreover, a weak regular ^*-product which connects a fundamental weak regular ^*-semigroup with corresponding projective partial groupoid is defined and characterized. It is finally proved that every weak regular ^*-product is in fact a weak regular ^*-semigroup and any weak regular ^*-semigroup is constructed in this way.     

储存环高频剔除系统

 介绍了用于电子储存环部分填充和非均匀填充的一种实验装置,它利用储存环中电子运动所具有的横向自由振荡和束团脉冲的时间结构这一特性,采用外加激励的方法使其产生共振,从而使得储存环中部分束团中的电子丢失,形成储存环的部分填充和非均匀填充。还扼要介绍了用高频剔除系统在储存环上实现不同填充方式时的束流积累结果。     

物光的偏振性对全息记录质量的影响

通过对菲涅耳三维漫反射全息记录光路中物光与参考光偏振状态的实验检测，发现线偏振的激光被不同表面材料的物体散射和漫反射后变成“部分偏振光”，几乎所有目标物都有显著的消偏振现象，全息干板上实际记录的是线偏振的参考光与“部分偏振”的物光形成的相干度较低的干涉条纹。物光偏振度的大幅度下降影响干涉条纹的衬比度，并增加全息图的噪声。给出实验方案和检测光路，采用在参考光路中插入1/4波片的方法，可充分利用非偏振物光各个振动方向的光能，提高条纹的衬比度。