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1.
Dynamical analysis,circuit realization,and application in pseudorandom number generators of a fractional-order laser chaotic system
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Chenguang Ma 《中国物理 B》2021,30(12):120504-120504
A new five-dimensional fractional-order laser chaotic system (FOLCS) is constructed by incorporating complex variables and fractional calculus into a Lorentz-Haken-type laser system. Dynamical behavior of the system, circuit realization and application in pseudorandom number generators are studied. Many types of multi-stable states are discovered in the system. Interestingly, there are two types of state transition phenomena in the system, one is the chaotic state degenerates to a periodical state, and the other is the intermittent chaotic oscillation. In addition, the complexity of the system when two parameters change simultaneously is measured by the spectral entropy algorithm. Moreover, a digital circuit is design and the chaotic oscillation behaviors of the system are verified on this circuit. Finally, a pseudo-random sequence generator is designed using the FOLCS, and the statistical characteristics of the generated pseudo-random sequence are tested with the NIST-800-22. This study enriches the research on the dynamics and applications of FOLCS. 相似文献
2.
《Electroanalysis》2006,18(6):595-604
The following two numerical models have been applied to zinc cations electroreduction in 1 M NaClO4 water solution: a classical EE model describing the concentration of involved species in solution (semi infinitive diffusion region), an extended EE model describing both: the concentration of involved species in solution and the concentration of metallic zinc inside mercury drop (in limited area of diffusion). In the latter model the inner part of mercury drop and surrounding solution were treated as dynamic interrelated system. Both models were applied to experimental cyclic voltammetric CV data in 1 M NaClO4, the results compared and discussed. The concentration profiles of all species including metallic zinc inside mercury drop were performed. The presented integrated model is essential for theoretical and analytical aspects of the electrochemistry of mercury soluble metal cations and amalgams. 相似文献
3.
托卡马克工程试验混合堆等离子体性能的等值线图分析 总被引:3,自引:3,他引:0
盛光昭 《核聚变与等离子体物理》1989,9(1):29-36
本文简要叙述托卡马克工程试验混合堆等离子体概念设计的物理基础,对等离子体性能进行了等值线图(Plasma Operation Contour)分析。根据工程试验混合堆的要求,得出一组等离子体参数。 相似文献
4.
In this paper we study the Hankel convolution operators on the space of even and entire functions and on Schwartz distribution spaces. We characterize the Hankel convolution operators as those ones that commute with Hankel translations and with a Bessel operator. Also we prove that the Hankel convolution operators are hypercyclic and chaotic on the spaces under consideration. 相似文献
5.
6.
Statistical Inference with Fractional Brownian Motion 总被引:3,自引:1,他引:2
Kukush Alexander Mishura Yulia Valkeila Esko 《Statistical Inference for Stochastic Processes》2005,8(1):71-93
We give a test between two complex hypothesis; namely we test whether a fractional Brownian motion (fBm) has a linear trend against a certain non-linear trend. We study some related questions, like goodness-of-fit test and volatility estimation in these models. 相似文献
7.
Teresa uczak Radosaw Pankiewicz Bogusawa ska Grzegorz Schroeder Maria Betowska-Brzezinska Bogumil Brzezinski 《Journal of Molecular Structure》2006,800(1-3):140-145
Novel self-assembled monolayers were obtained on silver using 4,7-diazaheptyl-trimethoxy-silane (SiN) and vinyl-trialkoxy-silane (SiVA, where the alkyl group is 3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-eicozaoxa- hexaheptaconan). It was shown that thus modified metal surface was protected against electrooxidation. A densely packed monolayer remained stable and did not desorb from the Ag electrode on the potential cycling. The structure of SiN and SiVA as well as their complexes with Li+ cations were calculated and visualised by the AM1d and PM5 semi-empirical methods. 相似文献
8.
In this paper, the special construction of a parallel robot, called spatial servopneumatic multi-axis test facility, will be discussed. The investigations include the following aspects: (i) the laboratory set-up of the robot, (ii) various results obtained in laboratory experiments, taking into account quite different control algorithms and command-input signals, (iii) a comparison of the laboratory experiments with the computer simulations of Part I of this paper, and ({vi}) a quality check of the results compared with the cost of the different controller realizations. The results of both the computer simulations and the laboratory experiments show: (i) The dynamic behavior of the parallel structure can be tremendously improved by using sophisticated nonlinear control algorithms. (ii) This improvement has to be paid by a drastically increased amount of work for deriving the model equations and control algorithms, and by augmented hardware cost of the sensing elements and controller electronics. (iii) Carefully developed model equations and identified model parameters provide theoretical models of the complex parallel structure that are very close to reality. This enables the design engineer to systematically investigate constructive alternatives of the design parameters, sensor and actuator concepts, and control strategies of the MAP prior to their hardware realization.This work has been supported by the German Science Foundation (DFG) under Contract No. Ha 1666/6-3. 相似文献
9.
Stress-Strain State in the Zone of Load Transfer in a Composite Specimen under Uniaxial Tension 总被引:2,自引:2,他引:0
Kulakov V. L. Tarnopol'skii Yu. M. Arnautov A. K. Rytter J. 《Mechanics of Composite Materials》2004,40(2):91-100
The stress-strain state in the zone of load transfer in a uniaxially stretched specimen made of a unidirectional epoxy carbon-fiber-reinforced plastic (CFRP) is investigated. A parametric analysis of the influence of geometric and mechanical characteristics of the specimen on its stress-strain state is performed by means of finite-element modeling. The parameters allowing us to significantly reduce the dangerous concentration of transverse and tangential stresses are revealed. The mechanical tensile characteristics of a high-strength pultruded unidirectional CFRP are determined experimentally, and the size effect of its strength is estimated. 相似文献
10.
Given a tree
with leaf set X, there are certain ways of arranging the elements of X in a circular order so that
can be embedded in the plane and ‘preserve’ this ordering. We investigate some new combinatorial properties of these ‘circular orderings.’ We then use these properties to establish two results concerning dissimilarity maps on X that are induced by edge-weighted trees with leaf set X. 相似文献