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51.
An encryption scheme based on phase-shifting digital holography and amplitude-phase disturbance 下载免费PDF全文
In this paper, we propose an encryption scheme based on phase-shifting digital interferometry. According to the original system framework, we add a random amplitude mask and replace the Fourier transform by the Fresnel transform.We develop a mathematical model and give a discrete formula based on the scheme, which makes it easy to implement the scheme in computer programming. The experimental results show that the improved system has a better performance in security than the original encryption method. Moreover, it demonstrates a good capability of anti-noise and anti-shear robustness. 相似文献
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徐宁 《数学年刊A辑(中文版)》2013,34(3):269-278
设$H(\mathbb{B})$为单位球上全纯函数类,研究了单位球上 Zygmund 空间到 Bloch 空间上径向导数算子$\Re$与积分型算子$I_\varphi^g$乘积的有界性和紧性,
这里
$$
I_\varphi^g f(z)=\int_0^1 \Re f(\varphi(tz))g(tz)\frac{{\rm d}t}{t},\quad z\in\mathbb{B},
$$
其中$g\in H(\mathbb{B}),\ g(0)=0$, $\varphi$ 是$\mathbb{B}$上全纯自映射. 相似文献
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以乙酸乙酯对印刷废液进行预处理,并用GC测定处理后样品溶液中苯、甲苯、和二甲苯.方法加标回收率为95.72%-102.66%,6次测定的RSD(n=6)小于3.29%.方法操作方便,分析速度快,结果准确. 相似文献
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基于信任管理引擎的信任管理模型,提出了信任管理是信任意向的获取、评估和实施的新定义,并应用于已有的一个新型网格安伞信任体系架构(NGST)中,将网格环境划分为多个自治域,每个自治域由一个信任代理处理本域所有信任关系的问题.在此环境下建立了域内信任管理模型,给出了安全性的形式分析与证明,利用凭证访问策略来保护协商双方的安全凭证中的敏感信息.结果表明,本文提出的信任管理模型是安全的,具备很好的自治性,并且能有效地将不良行为较多实体逐出自治域. 相似文献
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The effect of hydrostatic pressure (up to 28 MPa) on Brillouin frequency shift (BFS) within two types of bare, single-mode fibers is studied via Brillouin optical time domain analysis technique. Experimental results show a negative linear relation between pressure and BFS, with almost the same sensitivity in both types of fibers. The average value of experimental slopes is -0.742 MHz/MPa. This value is found to be well suited to theoretical analysis on the basis of data on bulk silica glass in previous reports. This preliminary evaluation may result in a new method for distributed pressure sensing along silica optical fiber. 相似文献
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关于(cos(A/2))~n+(cos(B/2))~n+(cos(C/2))~n的上下限估计徐宁(湖北省通城县关刀实验中学437400)设A、B、c为三角形的三个内角,关于_A_B_C。。_。__ACOS”、+cos”、+cos”、(以下简记为了COs?.. 相似文献