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91.
Security of quantum key distribution using two-mode squeezed states against optimal beam splitter attack
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For the beam splitter attack strategy against quantum key distribution using two-mode squeezed states, the analytical expression of the optimal beam splitter parameter is provided in this paper by applying the Shannon information theory. The theoretical secret information rate after error correction and privacy amplification is given in terms of the squeezed parameter and channel parameters. The results show that the two-mode squeezed state quantum key distribution is secure against an optimal beam splitter attack. 相似文献
92.
The possible effects of radiation exposure to DNA are studied by investigations for the thymine residue. Detailed analysis of the various addition and other products is undertaken theoretically, using the semiempirical AM1 procedure. The results agree with the experimental finding that the loss of hydrogen on radiation exposure occurs from the C5-methyl group and hydroxyl radical addition occurs at C6, yielding the ‘5-yl’ radical. This radical is nonplanar, the axial conformer being slightly preferred over the equatorial one. In contrast, the other possible radical, the ‘6-yl’ radical, is almost planar. These results are important in understanding the conformational changes in DNA as a consequence of radiation exposure. 相似文献
93.
YANG Qiu-Ying ZHANG Ying-Yue ZHANG Gui-Qing CHEN Tian-Lun 《理论物理通讯》2008,49(4):965-970
In this paper, we investigate the effect due to the change of topology structure of network on the nonlinear dynamical behavior, by virtue of the OFC neuron evolution model with attack and repair strategy based on the small world. In particular, roles of various parameters relating to the dynamical behavior are carefully studied and analyzed. In addition, the avalanche and EEC-like wave activities with attack and repair strategy are also explored in detail in this work. 相似文献
94.
先计算出高超音速零攻角尖锥边界层的定常层流流场.然后在计算域的入口引入两组有限幅值的T-S波扰动,对空间模式的转捩过程进行了直接数值模拟.分析了转捩过程的机理,发现平均流剖面稳定性的变化是其关键.并进一步讨论了不同模态初始扰动在高超音速尖锥边界层中的演化规律. 相似文献
95.
Public-Key Cryptography (PKC) based on multivariate quadratic equations is one of the most promising alternatives for classical PKC after the eventual coming of quantum computers. Recently, Shen and Tang proposed a new MQ-signature scheme, RGB, based on three types of variables, Red(r), Green(g) and Blue(b). They claimed that signing for RGB is faster than that of UOV and Rainbow. At ACISP 2016, Tang et al. implemented RGB on S5PV210 and MT6582 microprocessors at 64, 80, 96, 118 and 128-bit security levels for practical use. Their results are much more efficient than other MQ-signature schemes, so RGB is very appealing for resource-limited devices. We show that RGB with their suggested parameters at 64, 80, 96, 118 and 128 security levels are entirely broken by key recovery attacks using good keys. From a practical point of view, we are able to break their parameters at 64, 80, 96, 118 and 128 security levels in less than 0.48 seconds, 1.7 seconds, 90.68 seconds, 11 minutes and 6.82 hours, respectively. Consequently, we show that signing and the key sizes for RGB with secure parameter sets are much slower and larger than those of UOV and Rainbow. 相似文献
96.
We propose a unidimensional two-way continuous-variable quantum key distribution protocol with coherent states, where the sender modulates a single quadrature of the coherent states rather than both quadratures to simplify the structure of a two-way system. Security analysis is performed with a general attack strategy, known as two-mode attack, which helps to reduce limitations in the analysis. The performance of the protocol under all accessible two-mode attacks at fixed distance is illustrated. Further, two typical two-mode attack strategies are obtained from it, which are one-mode attack strategy and optimal two-mode attack strategy. Between them, the one-mode attack is the simplest form of the two-mode attack, while the optimal two-mode attack is the most complicated one. Simulations show that though the system is simplified, the performance of the two-way protocol with unidimensional modulation is still comparable to that of the counterpart with Gaussian modulation even against the optimal two-mode attack when Eve’s ability is maximized. Thus, the proposed protocol simplifies the two-way system while guaranteeing its performance to a certain extent. Especially in a practical system with short transmission distance and high excess noise, the protocol has a good application prospect. 相似文献
97.
联合直接攻击弹药精确制导技术分析 总被引:3,自引:0,他引:3
从技术分析的角度对联合直接攻击弹药(JDAM)的武器制导系统进行了研究。安装JDAM制导控制装置的弹药武器,通过GPS/INS组合制导和尾翼调节,控制武器精确命中目标。在对JDAM系统组成和精度分析的基础上,详细讨论了JDAM系统的卡尔曼滤波器、捷联惯性导航技术、传递对准和GPS辅助惯性制导等技术。对设计中遇到主要的技术难点和相应的解决途径也进行了分析。 相似文献
98.
有序态Fe3Al合金在水环境中的磨粒磨损行为 总被引:1,自引:0,他引:1
研究了不同载荷下含Cr的B2和DO3有序态Fe3Al合金在水中的磨粒磨损行为。采用扫描电镜分析了合金的磨损表面形貌和磨屑形貌。二次离子质谱分析结果表明:在水环境磨损条件下,随着载荷的增加,进入Fe3Al合金表层的氢浓度升高,合金表层的氢损伤加剧。在高载荷下由机械磨损所引起的材料流失仍占主导地位,相同载荷下B2有序态Fe3Al合金的磨损质量损失比DO3有序态Fe3Al合金低。 相似文献
99.
100.