用于可信任中继量子密钥分配网络的差异化服务提供机制(英文)

为了向用户提供差异化的密钥服务,研究了配备密钥池的可信任量子密钥分配网络.首先,理论分析了数据包时延和密钥池的关系,给出了具体关系式,指出带有密钥池缓存功能的量子密钥分配网络的平均数据包时延与密钥产生速率、密钥池的初始密钥长度、以及数据包的平均长度、到达时间和到达率密切相关.对比理论分析和软件仿真结果,验证了时延分析的正确性.其次,将密钥提供服务分为三类:保证提供型、优先提供型和尽力提供型,并提出了相应的技术实现方案,即提前预约、逐跳插队和逐跳排队;最后,仿真结果表明差异化密钥服务提供机制是有效的.     

求解非线性动力学方程的预测-校正数值算法

提出了一种求解非线性动力学方程的预测-校正数值算法.由于校正过程消除了线性化带来的误差,使计算精度得到较大提高.数值算例表明该方法正确、有效.     

Delay-dependent stochastic stability criteria for Markovian jumping neural networks with mode-dependent time-varying delays and partially known transition rates

In this paper, the problem of stochastic stability criterion of Markovian jumping neural networks with mode-dependent time-varying delays and partially known transition rates is considered. Some new delay-dependent stability criteria are derived by choosing a new class of Lyapunov functional. The obtained criteria are less conservative because free-weighting matrices method and a convex optimization approach are considered. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.     

The interaction of relativistic electron beam with the electromagnetic field in the neighbourhood of a caustic region

We present the theory of self-consistent interaction of crooked relativistic electron beam within and near the e.m. field caustic zones of jumping ball and whispering gallery types being formed in open resonators of elliptical cylindrical symmetry. On the basis of numerical analysis of nonlinear system of equations by applying a large-particles method, the principal possibility to design the multiwave synchro-Cherenkov amplifiers and generators is shown.     

The radio frequency conductivity of some aliphatic alcohols at different temperatures

Activation energies for viscous flow and conductivity are computed from experimental values of RF conductivity (frequency 400 kHz) at different temperatures for eight polar liquids. It is observed that for aliphatic alcohols the activation energy for conductivity is greater than that for viscous flow. However, their ratio is slightly greater than unity and is different for different alcohols whereas for nonassociating polar liquids the ratio is almost equal to unity. The dependence of conductivity on viscosity for the liquid alcohols does not follow the Walden’s law but can be well represented by Adamczewskis relation.     

Using Lagrangians of Hypergraphs to Find Non-Jumping Numbers (I)

Let r ≥ 2 be an integer. A real number is a jump for r if for any and any integer m, m ≥ r, any r-uniform graph with vertices and density at least contains a subgraph with m vertices and density at least α + c, where c = c(α) does not depend on or m. It follows from a result of Erdős, Stone, and Simonovits that every is a jump for r = 2. Erdőos asked whether the same is true for r ≥ 3. Frankl and R?dl gave a negative answer by showing an infinite sequence of non-jumping numbers for r ≥ 3. However, there are a lot of unknowns on determining whether a number is a jump for r ≥ 3. In this paper, we first find two infinite sequences of non-jumping numbers for r = 4, then we extend one of the results to every r ≥ 4. Our approach is still based on the approach developed by Frankl and R?dl. Received November 30, 2005     

Improved H∞ performance analysis of uncertain Markovian jump systems with overlapping time‐varying delays

In this article, we study the problem of robust H_∞ performance analysis for a class of uncertain Markovian jump systems with mixed overlapping delays. Our aim is to present a new delay‐dependent approach such that the resulting closed‐loop system is stochastically stable and satisfies a prescribed H_∞ performance level χ. The jumping parameters are modeled as a continuous‐time, finite‐state Markov chain. By constructing new Lyapunov‐Krasovskii functionals, some novel sufficient conditions are derived to guarantee the stochastic stability of the equilibrium point in the mean‐square. Numerical examples show that the obtained results in this article is less conservative and more effective. The results are also compared with the existing results to show its conservativeness. © 2016 Wiley Periodicals, Inc. Complexity 21: 460–477, 2016     

Using Lagrangians of hypergraphs to find non-jumping numbers(II)

Let r?2 be an integer. A real number α∈[0,1) is a jump for r if for any ε>0 and any integer m?r, any r-uniform graph with n>n₀(ε,m) vertices and density at least α+ε contains a subgraph with m vertices and density at least α+c, where c=c(α)>0 does not depend on ε and m. A result of Erd?s, Stone and Simonovits implies that every α∈[0,1) is a jump for r=2. Erd?s asked whether the same is true for r?3. Frankl and Rödl gave a negative answer by showing an infinite sequence of non-jumping numbers for every r?3. However, there are a lot of unknowns on determining whether or not a number is a jump for r?3. In this paper, we find two infinite sequences of non-jumping numbers for r=4, and extend one of the results to every r?4. Our approach is still based on the approach developed by Frankl and Rödl.     

Stochastic finite-time boundedness of Markovian jumping neural network with uncertain transition probabilities

The stochastic finite-time boundedness problem is considered for a class of uncertain Markovian jumping neural networks (MJNNs) that possess partially known transition jumping parameters. The transition of the jumping parameters is governed by a finite-state Markov process. By selecting the appropriate stochastic Lyapunov–Krasovskii functional, sufficient conditions of stochastic finite time boundedness of MJNNs are presented and proved. The boundedness criteria are formulated in the form of linear matrix inequalities and the designed algorithms are described as optimization ones. Simulation results illustrate the effectiveness of the developed approaches.     

Vector solitons in semiconductor quantum dots

A theory of an optical vector soliton of self-induced transparency in an ensemble of semiconductor quantum dots is considered. By using the perturbative reduction method, the system of the Maxwell–Liouville equations is reduced to the two-component coupled nonlinear Schrödinger equations. It is shown that a distribution of transition dipole moments of the quantum dots and phase modulation changes significantly the pulse parameters. The shape of the optical two-component vector soliton with the sum and difference of the frequencies in the region of the carrier frequency is presented. The vector soliton can be reduced to the breather solution of self-induced transparency with a different profile. Explicit analytical expressions in the presence of single-excitonic and biexcitonic transitions for the optical vector soliton are obtained with realistic parameters which can be reached in current experiments.