H^p（D）函数的两个新刻划

证明了关于单位圆盘D上的H^p函数的两个新的等价命题。     

基于粗糙集理论的知识约简及应用实例

在保持分类能力不变的前提下 ,通过利用粗糙集理论中的知识约简方法 ,在保护知识库分类不变的条件下 ,删除其中不相关或不重要的知识 ,从而导出问题的决策 .利用基于决策表的粗糙集模型算法 ,实例分析如何数字化表示决策表 ,并对其进行属性约简和属性值的约简 ,从而提取决策规则 .     

Improving nucleation in the fabrication of high-quality 3D macro-porous copper film through the surface-modification of a polystyrene colloid-assembled template

A new approach is developed to the fabrication of high-quality three-dimensional macro-porous copper films. A highly-ordered macroporous copper film is successfully produced on a polystyrene sphere (PS) template that has been modified by sodium dodecyl sulfate (SDS). It is shown that this procedure can change a hydrophobic surface of PS template into a hydrophilic surface. The present study is devoted to the influence of the electrolyte solution transport on the nucleation process. It is demonstrated that the permeability of the electrolyte solution in the nanochannels of the PS template plays an important role in the chemical electrodeposition of high-quality macroporous copper film. The permeability is drastically enhanced in our experiment through the surface modification of the PS templates. The method could be used to homogeneously produce a large number of nucleations on a substrate, which is a key factor for the fabrication of the high-quality macroporous copper film.     

基于斯托克斯矢量的偏振成像仪器及其进展

偏振成像技术将景物的偏振信息转化为二维图像信息,从而可以和灰度图像一样对目标景物进行场景特征分析。介绍了基于斯托克斯矢量的偏振成像原理。按照获取斯托克斯矢量方法的不同,分别介绍了偏振片起偏、偏振棱镜分光和可变延迟波片调制三类分时偏振成像方式,分振幅、分孔径、分焦平面三种同时偏振成像方式。结合我国的制造水平,设计了双CCD渥拉斯顿棱镜同时偏振成像实验系统,并采集了实验图像。分析了各种偏振成像方式的优缺点。指出了偏振激光照明主动偏振成像、光谱偏振成像是偏振成像仪器进一步的发展方向。     

基于光导开关的Blumlein型PFN能量转换效率

为了驱动低能重复频率高阻抗X光管,采用低感陶瓷电容构建了一套电长度约33.5 ns、阻抗约8 的Blumlein型脉冲形成网络（BPFN）,在匹配负载条件下研究了采用GaAs光导开关（PCSS）作为脉冲输出开关时PCSS工作场强、激光触发能量与能量转换效率的关系。实验表明:PCSS截止场强为3.21～4.94 kV/cm,在工作场强高于20 kV/cm时,截止场强引起的能量损失对能量转换效率的影响不大;PCSS较高的导通电阻是影响PFN能量转换效率的主要因素,随着工作场强、激光触发能量的上升,能量转换效率呈指数上升趋势。     

色散补偿光子晶体光纤结构参数对其色散的影响

光子晶体光纤由于其灵活可调的色散特性用作色散补偿具有极大的应用潜力. 设计了一种色散补偿光子晶体光纤, 并运用频域有限差分法模拟了其色散特性,从理论上分析了其结构参数孔间距Λ和空气占空比d/Λ对该光子晶体光纤的色散系数的影响, 并且实际制备出了3种不同结构参数的光子晶体光纤. 通过对其色散曲线对比分析表明: 当光子晶体光纤孔间距在1 μm附近时, 其色散系数随着孔间距Λ和占空比d/Λ的增大而增加, 但对于孔间距Λ的变化比占空比d/Λ更为敏感, 并且随着孔间距Λ的增加,其对色散系数的影响能力逐渐减小. 设计并制备的光子晶体光纤在1550 nm处的色散系数为-241.5 ps·nm^-1·km^-1, 相对色散斜率为0.0018, 具有较好的色散补偿能力. 关键词： 色散 色散补偿 光子晶体光纤 结构参数     

椭圆强非局域空间光孤子

对傍轴椭圆高斯光束在具有椭圆对称响应特性的强非局域非线性介质中的演化规律进行研究，得到了光束各参量演化的精确解析解，分析了单向空间光孤子和强非局域椭圆空间光孤子的形成条件，发现了椭圆光孤子的相移与介质响应函数的椭圆率有关. 关键词： 椭圆对称强非局域响应介质 椭圆强非局域空间光孤子 相移     

Analysis of the Coaxial Ridge-Loaded Helical Groove Waveguide

The coaxial ridge-loaded helical groove waveguide is proposed in this paper. As an all-metal slow-wave circuit, it has advantages of good heat dissipation and great size, and thus is suitable for use of millimeter TWT. By means of field theory, the expressions of the dispersion equation and the coupling impedance of the coaxial ridge-loaded helical groove waveguide are obtained. The influence of various circuit dimensions on the dispersion relation and the coupling impedance is investigated by the results of numerical computation.     

外应力场下铁磁/反铁磁双层膜系统的铁磁共振性质

从系统能量出发，采用Smith和Beljers理论方法研究了铁磁/反铁磁双层膜系统在外应力场下的铁磁共振现象.本模型中铁磁薄层具有单轴磁晶各向异性和立方磁晶各向异性，而反铁磁层非常薄因而其能量可忽略.推导出了该系统的铁磁共振频率和频谱宽度的解析式.结果表明：外应力场仅在低磁场下对具有立方磁晶各向异性系统的铁磁共振有影响，且区分弱磁场和强磁场的临界场依赖于外应力场的方向. 关键词： 铁磁/反铁磁双层膜 交换偏置 铁磁共振 应力场     

Broadband waveguide intersections with low cross talk in photonic crystal circuits

We propose a new mechanism for constructing waveguide intersections with broad bandwidth and low cross talk in photonic crystal (PC) circuits. The intersections are created by combination of coupled-cavity wave-guides (CCWs) with conventional line-defect waveguides. This mechanism utilizes the strong dependence of the defect coupling on the field pattern in the defects and the alignment of the defects (i.e., the coupling angle) in CCWs. By properly designing the defect mode, we demonstrate through numerical simulation the establishment of such a waveguide intersection in one of the most useful PCs, which is based on a two-dimensional triangular lattice of air holes made in a dielectric material. The transmission of a 500-fs pulse at ~1.3 microm is simulated by use of the finite-difference time-domain method, showing negligible distortion and low cross talk.