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991.
Min-Sung Kang Chang-Ho Hong Jino Heo Jong-In Lim Hyung-Jin Yang 《International Journal of Theoretical Physics》2014,53(6):1862-1866
This comment explains that the quantum signature scheme proposed by Ming-Xing Luo et al. (in Int. J. Theor. Phys. 51:2134, 2012) cannot satisfy the signature requirements. The comment presents methods of possible attacks by forgers, while also demonstrating that it is difficult to proceed by the normal protocol because of some errors in the formula of the scheme. 相似文献
992.
The purpose of the study is to summarize the application rule of sine wave and other simple symmetrical wave signal magneto-optical modulation in azimuth measurement, and acquire the limit on modulation signal when establishing azimuth measurement model. Firstly, we analyze the principle of traditional azimuth measurement system based on sine wave signal magneto-optical modulation, and establish the error free measurement model based on trigonometric function, after that we present the measurement models based on mixed signal with tangent, cosine and sine function, respectively. Secondly, we discuss the application feasibility of rectangle wave, triangle wave and sawtooth wave signal magneto-optical modulation in azimuth measurement respectively, and establish the azimuth measurement models based on rectangle wave and triangle wave signal modulation respectively, and analyze the reason why the sawtooth wave signal modulation cannot be applied in the azimuth measurement. Finally, we summarize the four simple signal magneto-optical modulation and acquire the requirements on modulation signal when establishing the azimuth measurement model based on simple wave single magneto-optical modulation. The study has an important guiding significance on the application of simple symmetrical wave magneto-optical modulation in azimuth measurement. 相似文献
993.
By introducing four potential functions, the governing equations of plane problems in 1D orthorhombic quasicrystals with piezoelectric effect are composed of four second-order partial differential equations, in which the quasi-harmonic functions are the essential unknowns. The general solution of these equations is further established, and all expressions are expressed in terms of the potential functions. As an application of the general solution, the closed-form solutions are obtained for wedge problems or half-plane problems of 1D orthorhombic piezoelectric quasicrystals. 相似文献
994.
The ratio of K(S)K(S) (K(L)K(L)) and K(L)K(L) production rates is calculated by considering K(0) - K(0) oscillation in J/psi --> K(0)K(0) decay. The theoretical uncertainty due to strong interaction in J/psi decay is completely canceled in the ratio; therefore, the absolute branching fractions of the CP-violating processes of J/psi --> K(S)K(S) and K(L)K(L) can be cleanly and model-independently determined in the case that J/psi K(S)K(L) decay is precisely measured. In the future tau-charm factory, the expected CP violating process of J/psi --> K(S)K(S) should be reached. It is important to measure J/psi to K(S)K(S) and K(S)K(L) decays simultaneously, so that many systematic errors will be canceled. More precise measurements are suggested to examine the predicted isospin relation in J/psi --> KK decays. All results can be extended to decays of other vector quarkonia, phi, psi(2S), and gamma(1S), etc. 相似文献
995.
针对基于剪切干涉原理的光刻投影物镜波像差检测设备中相移测量的需求,设计了一种移相装置.该装置采用了桥式放大机构,获得了较大放大比和相对紧凑的结构.从原理上对桥式放大机构进行了分析和讨论,得到了输入位移与其放大比之间的函数关系,并得到了其关系曲线.经过非线性有限元分析,对该装置的变形、受力和模态特性进行了验证.验证结果满足检测平台移相要求. 相似文献
996.
We experimentally evaluate and correct the non-equivalence between electrical and radiative heating of solar irradiance absolute radiometer to compensate the systematic error of radiant power measurement at ambient pressure. A relative difference of the order of 0.08%-0.27% between electrical and radiative heating sensitivities is shown, and the resulting non-equivalence correction factor is calculated. The radiant power measurement equation is modified using the non-equivalence correction factor, a systematic deviation of 0.19% of radiant power measurement is hence eliminated. 相似文献
997.
We propose multisymplectic implicit and explicit Fourier pseudospectral methods for the Klein-Gordon-Schrödinger equations. We prove that the implicit method satisfies the charge conservation law exactly. Both methods provide accurate solutions in long-time computations and simulate the soliton collision well. Numerical results show the abilities of the two methods in preserving charge, energy, and momentum conservation laws. 相似文献
998.
Yang Li Zhen-Hua Ye Chun Lin Xiao-Ning Hu Rui-Jun Ding Li He 《Optical and Quantum Electronics》2013,45(7):641-648
Current–voltage characteristics of HgCdTe photodiodes in the forward bias region have been modeled considering mechanisms including drift-diffusion current, recombination current, metal-semiconductor contact and constant series resistance. Moreover, a fitting method based on the genetic algorithm has been developed to obtain values of related physical parameters from the measured dynamic resistance–voltage curves. Fitting results of $n^+$ -on- $p$ planar devices with different cutoff wavelengths are presented to illustrate the model and method, which are available and promising in acquiring device parameter values and evaluating the electrode contact quality. 相似文献
999.
大学物理的电磁学部分,对后续理论课程和工程应用都十分重要.在讲授时可以将基本物理理论与前沿科研应用相结合,培养学生的创新思维,同时使得物理知识贴近生活,具有鲜明的时代特征.提出了一种平行板电流电感梯度的近似计算方法,并利用有限元软件进行仿真,分析了该近似方法的适用条件. 相似文献
1000.