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971.
Chih-Hung Chang Chun-Wei Yang Tzonelih Hwang 《International Journal of Theoretical Physics》2016,55(9):3993-4004
Recently, Yang and Hwang (Quantum Inf. Process. 13(3): 781–794, 19) proposed two fault-tolerant QKD protocols based on their proposed coding functions for resisting the collective noise, and their QKD protocols are free from Trojan horse attack without employing any specific detecting devices (e.g., photon number splitter (PNS) and wavelength filter). By using four-particle Greenberger-Horne-Zeilinger (GHZ) state and four-particle GHZ-like state in their proposed coding functions, Yang and Hwang’s QKD protocols can resist each kind of the collective noise–collective-dephasing noise, collective-rotation noise. However, their proposed coding function can be improved by the utilization of three-particle GHZ state (three-particle GHZ-like state) instead of four-particle GHZ state (four-particle GHZ-like state) that will eventually reduce the consumption of the qubits. As a result, this study proposed the improved version of Yang and Hwang’s coding functions to enhance the qubit efficiency of their schemes from 20 % to 22 %. 相似文献
972.
Junyong Li Xiaomin Gu Xiaosheng Yuan Qiqi Qiu Jie Sun Haibo Wang 《Journal of fluorescence》2016,26(4):1219-1224
A novel method to recognize cis/trans isomers was studied here. The naphthalimide dye as guest could bind with host cucurbit [7]uril (CB [7]) and 1:1 naphthalimide dye ? CB [7] assembly was formed. Moreover, this assembly was used as a fluorescent probe to recognized Fumaric acid (FA) and maleic acid (MA) via fluorescence titration. Two carboxyls in MA are in the same side, they could form stable interaction with the assembly and the fluorescence intensity decreased obviously when naphthalimide dye ? CB [7] was titrated by MA (nearly quenched in 1.5 equiv). But two carboxyls in FA are in opposite sides, the interaction between FA and the assembly was weak and not stable, and the fluorescence intensity changed inconspicuously when the assembly was titrated by FA. 相似文献
973.
A comparison of electrochemical performance between LiFe0.4Mn0.595Cr0.005PO4/C and LiMnPO4/C cathode materials was conducted in this paper. The cathode samples were synthesized by a nano-milling-assisted solid-state process using caramel as carbon sources. The prepared samples were investigated by XRD, SEM, TEM, energy-dispersive X-ray spectroscopy (EDAX), powder conductivity test (PCT), carbon-sulfur analysis, electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge cycling. The results showed that LiFe0.4Mn0.595Cr0.005PO4/C exhibited high specific capacity and high energy density. The initial discharge capacity of LiFe0.4Mn0.595Cr0.005PO4/C was 163.6 mAh g?1 at 0.1C (1C = 160 mA g?1), compared to 112.3 mAh g?1 for LiMnPO4/C. Moreover, the Fe/Cr-substituted sample showed good cycle stability and rate performance. The capacity retention of LiFe0.4Mn0.595Cr0.005PO4/C was 98.84 % over 100 charge-discharge cycles, while it was only 86.64 % for the pristine LiMnPO4/C. These results indicated that Fe/Cr substitution enhanced the electronic conductivity for the prepared sample and facilitated the Li+ diffusion in the structure. Furthermore, LiFe0.4Mn0.595Cr0.005PO4/C composite presented high energy density (606 Wh kg?1) and high power density (574 W kg?1), thus suggested great potential application in lithium ion batteries (LIBs). 相似文献
974.
Robust decentralized adaptive synchronization of general complex networks with coupling delayed and uncertainties 下载免费PDF全文
The problem of robust decentralized adaptive synchronization of general complex networks with coupling delayed and uncertainties is investigated in this article. It is only assumed that the upper normal bound of uncertain inner and outer coupling matrices is positive but its concrete structure is not also required to be known. The time‐varying coupling delay is a any nonnegative continuous and bounded function and not require its derivative to be less than one, that is, general time‐varying coupling delays and uncertainties. For such a class of uncertain complex networks, a new synchronization scheme is presented by a class of continuous memoryless robust decentralized adaptive synchronization controllers. It is also shown that the synchronization error dynamics of uncertain complex networks can be guaranteed as uniformly exponentially convergent toward a ball that can be as small as desired. Finally, numerical simulations are provided to demonstrate the effectiveness and robustness of proposed complex networks synchronization schemes. © 2013 Wiley Periodicals, Inc. Complexity 19: 10–26, 2014 相似文献
975.
976.
Lung-fu Chang 《Insurance: Mathematics and Economics》2009,44(1):59-69
A catastrophe put option is valuable in the event that the underlying asset price is below the strike price; in addition, a specified catastrophic event must have happened and influenced the insured company. This paper analyzes the valuation of catastrophe put options under deterministic and stochastic interest rates when the underlying asset price is modeled through a Lévy process with finite activity. We provide explicit analytical formulas for evaluating values of catastrophe put options. The numerical examples illustrate how financial risks and catastrophic risks affect the prices of catastrophe put options. 相似文献
977.
In traditional inventory models, it is implicitly assumed that the buyer must pay for the purchased items as soon as they have been received. However, in many practical situations, the vendor is willing to provide the buyer with a permissible delay period when the buyer’s order quantity exceeds a given threshold. Therefore, to incorporate the concept of vendor–buyer integration and order-size-dependent trade credit, we present a stylized model to determine the optimal strategy for an integrated vendor–buyer inventory system under the condition of trade credit linked to the order quantity, where the demand rate is considered to be a decreasing function of the retail price. By analyzing the total channel profit function, we developed some useful results to characterize the optimal solution and provide an iterative algorithm to find the retail price, buyer’s order quantity, and the numbers of shipment per production run from the vendor to the buyer. Numerical examples and sensitivity analysis are given to illustrate the theoretical results, and some managerial insights are also obtained. 相似文献
978.
R. S. Thompson Y. C. Chang J. G. Lu 《The European Physical Journal B - Condensed Matter and Complex Systems》2012,85(1):13
Influence of the weak electric field on the electronic structure of the Fibonacci
superlattice is considered. The electric field produces a nonlinear dynamics of the energy
spectrum of the aperiodic superlattice. Mechanism of the nonlinearity is explained in
terms of energy levels anticrossings. The multifractal formalism is applied to investigate
the effect of weak electric field on the statistical properties of electronic
eigenfunctions. It is shown that the applied electric field does not remove the
multifractal character of the electronic eigenfunctions, and that the singularity spectrum
remains non-parabolic, however with a modified shape. Changes of the distances between
energy levels of neighbouring eigenstates lead to the changes of the inverse participation
ratio of the corresponding eigenfunctions in the weak electric field. It is demonstrated,
that the local minima of the inverse participation ratio in the vicinity of the
anticrossings correspond to discontinuity of the first derivative of the difference
between marginal values of the singularity strength. Analysis of the generalized dimension
as a function of the electric field shows that the electric field correlates spatial
fluctuations of the neighbouring electronic eigenfunction amplitudes in the vicinity of
anticrossings, and the nonlinear character of the scaling exponent confirms
multifractality of the corresponding electronic eigenfunctions. 相似文献
979.
利用紫外Mie散射激光雷达探测澳门地区沙尘暴事件 总被引:4,自引:0,他引:4
研制了一台工作波长为355nm的紫外高能Mie散射激光雷达,并利用该激光雷达在2010年一次沙尘暴事件期间对澳门上空的大气进行了探测,得到了澳门地区不同时刻的气溶胶消光系数垂直廓线。利用Fernald方法反演得到的气溶胶近地面消光系数随时间的变化与当地气象数据具有较好的一致性,气溶胶消光系数与当地可吸入颗粒物浓度的相关性达到了0.93。气溶胶垂直廓线显示,在沙尘暴来临期间存在明显的沙尘气溶胶凝集层。通过气溶胶轨迹倒推,分析了沙尘气溶胶的来源及路径。观测结果表明,该激光雷达可以在特殊天气条件下对澳门地区气溶胶进行有效探测,这将有助于深化对澳门上空气溶胶特性的研究。 相似文献
980.
Improvement of dielectric tunability and loss tangent of (Ba,Sr)TiO3 thin films with K doping 下载免费PDF全文
Zhang Wei-Jie Dai Jian-Ming Zhu Xue-Bin Chang Qing Liu Qiang-Chun Sun Yu-Ping 《中国物理 B》2012,21(9):97702-097702
Ba0.6Sr0.4TiO3 thin films doped with K were deposited on Pt/Ti/SiO2/Si substrates by chemical solution deposition method. The structure, surface morphology, and dielectric and tunable properties of Ba0.6Sr0.4TiO3 thin films have been studied in detail. The K content in Ba0.6Sr0.4TiO3 thin films has a strong influence on the material's properties including surface morphology, dielectric and tunable properties. It is found that the Curie temperature of K-doped Ba0.6Sr0.4TiO3 films shifts to higher values compared with that of undoped Ba0.6Sr0.4TiO3 thin films, which leads to a dielectric enhancement of K-doped Ba0.6Sr0.4TiO3 films at room temperature. At the optimized content of 0.02 mol, the dielectric loss tangent is reduced significantly from 0.057 to 0.020. Meanwhile, the tunability is enhanced obviously from 26% to 48% at the measured frequency of 1 MHz and the maximum value of the figure of merit is 23.8. This suggests that such films have potential applications for tunable devices. 相似文献