Copyright protection in digital museum based on digital holography and discrete wavelet transform

A new method to protect the copyright of digital museum based on digital holography is proposed. The Fresnel hologram of watermark image is embedded in the object to be protected through discrete wavelet transform （DWT）. After the watermark detection, the copyright information appears in the reconstructed hologram. With the higher redundancy feature in the hologram, the proposed technique can actually survive several kinds of image processing. Experimental results prove that the presented method has good robustness in image protection.     

高精度直流传感器DCCT标准测试系统

在北京正负电子对撞机二期改造工程(BEPC Ⅱ),磁铁电源系统大量使用了电流型直流传感器(DCCT)作为电源的反馈和回采器件.为了能够对DCCT的性能进行检测和校准,设计研制了高精度直流传感器DCCT标准测试系统.该测试系统主要由PC工控机、7又1/2数字万用表、超高精度直流传感器和高精度直流稳流电源构建而成.论文中主要介绍了测试系统的功能和系统软、硬件结构,并给出了测试系统在实际DCCT检测中的测量数据.     

一种时序逻辑网络的快速设计方法

引用1984年尹克震提出的“开关函数的反演公式”,采用伪随机序列技术的思想,提出移位寄存器型时序逻辑网络的一种快速设计方法。     

对三线摆测物体转动惯量实验的改进

本文介绍了三线摆测物体转动惯量实验中用光控数字毫秒计测量周期的方法，提高了测量精度。     

ON THE ORDER PROPERTIES OF DIGITAL CURVES IN THE PAN-EUCLIDEAN GEOMETRY

How to increase the speed in drawing and recognizing curves has always been a major concern. From the Breshenham Algorithm and DDA Algorithm in the sixties to the double-step and quadruple-step line generation iu the eighties, curves were all dragon point by point. The algorithm in this paper fully utilizes machine commands to accelerate the generation of lines and curves. We introduce and prove for the first time characterization theorems of the segment code order of digital lines and curyes. These theorems give new methods in the recognition and the measure of smoothness of lines and curves.     

数字剪切散斑干涉术中的刚体位移补偿的新方法

给出一个数字剪切散斑干涉术中的刚体位移补偿的新方法，当刚体位移大于一个像素时，加载前后的散斑图将会由于位置的变化导致失相关，重新安排每一个像素将会克服此失相关，散斑平均、条纹重构以及迭代方法用来改善条纹质量，消除散斑噪声，最后得到可取结果。     

Non-expansive Mappings and Iterative Methods in Uniformly Convex Banach Spaces

In this article, we will investigate the properties of iterative sequence for non-expansive mappings and present several strong and weak convergence results of successive approximations to fixed points of non-expansive mappings in uniformly convex Banach spaces. The results presented in this article generalize and improve various ones concerned with constructive techniques for the fixed points of non-expansive mappings.     

参数未知的不同阶数混沌系统广义同步及参数估计

采用扩阶方法(使响应系统和驱动系统的维数相同)，把不同阶数混沌系统的广义同步问题转化为相同阶数混沌系统之间的广义同步，基于Lyapunov稳定性定理和自适应控制方法(用于相同阶数混沌系统的同步)，给出了自适应控制器和参数自适应律，进而实现了不同阶数混沌系统的广义同步.将该方法应用于参数未知的超Lü，Lorenz，广义Lorenz和Liu等系统之间的广义混沌同步，理论证明了该方法可以使这些系统达到渐近广义同步，并且可以辨识驱动系统和响应系统的所有参数，数值模拟进一步证明了该方法的有效性.     

基于微极性弹性力学的碳纳米管中波的传播特性

基于微极性弹性理论推导出的碳纳米管的应力-应变关系，使用哈密顿原理建立了碳纳米管的动力学微分方程. 通过求动力学微分方程的波动解，获得碳纳米管中波的频率与波数的关系即弥散关系，另外还得到了波的群速度和特征波面. 对所得结果进行了讨论. 关键词： 微极性弹性力学 碳纳米管 群速度 特征波面