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61.
Milivoj Lovrić 《Electroanalysis》2021,33(11):2372-2380
A model of cyclic staircase voltammetry of enzymatic reactions on the rotating disk electrode is developed and the inhibition by the product is investigated. The responses are mostly time – dependent current – potential curves with maxima in the forward but not in the backward branch. If the maxima appear in both branches, the inhibition is potential – dependent either directly or indirectly. The source of the second maximum is explained. 相似文献
62.
63.
A flexible sheet was made with radiophotoluminescence (RPL) glass beads on an experimental basis for visualization of high beta-surface-contamination. A simple RPL observation system for remote contamination monitoring was constructed with a homemade UV floodlight and a commercially available digital camera with supplementary optical lenses and filters. In preliminary experiments, RPL images were well observed with the digital camera of the present system. Their precise RPL intensity was determined after the correction of nonlinear response of the camera. It was expected from experiments that RPL images of beta-surface-contamination could be quantitatively evaluated through calibration, i.e., the conversion of camera images to dose data on the sheet-type glass dosimeter. 相似文献
64.
CHEN Hai-Ling YANG Jun-Zhong 《理论物理通讯》2009,51(3):460-464
In this work, we investigate the amplitude death in coupled system with small number of nonlinear oscillators. We show how the transitions to the partial and the complete amplitude deathes happen. We also show that the partial amplitude death can be found in globally coupled oscillators either. 相似文献
65.
Lucas P. Tendela Alejandro FedericoGuillermo H. Kaufmann 《Optics and Lasers in Engineering》2011,49(2):281-284
This paper presents an interferometric measurement of the out-of-plane deflections produced by a piezoelectric transducer, manufactured by thick-film deposition of a ceramic paste over an alumina substrate, when is subjected to a DC electric voltage. It is shown that a digital speckle pattern interferometer with an incorporated phase-shifting facility allows the measurement of nanometer displacements generated by the piezoelectric device. These measurements are used to evaluate the effective piezoelectric charge constant along the polarization direction (d33)eff that characterizes the thick-film transducer. 相似文献
66.
Synchronization of different chaotic systems via active radial basis functions sliding mode controller 下载免费PDF全文
This paper presents a new method to synchronize different chaotic systems with disturbances via an active radial basis function (RBF) sliding controller. This method incorporates the advantages of active control, neural network and sliding mode control. The main part of the controller is given based on the output of the RBF neural networks and the weights of these single layer networks are tuned on-line based on the sliding mode reaching law. Only several radial basis functions are required for this controller which takes the sliding mode variable as the only input. The proposed controller can make the synchronization error converge to zero quickly and can overcome external disturbances. Analysis of the stability for the controller is carried out based on the Lyapunov stability theorem. Finally, five examples are given to illustrate the robustness and effectiveness of the proposed synchronization control strategy. 相似文献
67.
In this paper, we focus on the robust adaptive synchronization between two coupled chaotic neural networks with all the parameters unknown and time-varying delay. In order to increase the robustness of the two coupled neural networks, the key idea is that a sliding-mode-type controller is employed. Moreover, without the estimate values of the network unknown parameters taken as an updating object, a new updating object is introduced in the constructing of controller. Using the proposed controller, without any requirements for the boundedness, monotonicity and differentiability of activation functions, and symmetry of connections, the two coupled chaotic neural networks can achieve global robust synchronization no matter what their initial states are. Finally, the numerical simulation validates the effectiveness and feasibility of the proposed technique. 相似文献
68.
This paper firstly introduces the control methods to fractals and give the definition of synchronization of Julia sets between two different systems. Especially, the gradient control method is taken on the classic Julia sets of complex quadratic polynomial Zn+1 = zn^2+ c, which realizes its Julia sets control and synchronization. The simulations illustrate the effectiveness of the method. 相似文献
69.
This paper proposes an adaptive parameter identification method
for breaking chaotic shift key communication from the
transmitted signal in public channel. The sensitive dependence
property of chaos on parameter mismatch is used for chaos adaptive
synchronization and parameter identification. An index function
about the synchronization error is defined and conjugate gradient
method is used to minimize the index function and to search the
transmitter's parameter (key). By using proposed method, secure key
is recovered from transmitted signal generated by low dimensional
chaos and hyper chaos switching communication. Multi-parameters can
also be identified from the transmitted signal with noise. 相似文献
70.
A unified approach to fuzzy modelling and robust synchronization of different hyperchaotic systems 总被引:2,自引:0,他引:2 下载免费PDF全文
In this paper, a Takagi Sugeno (T-S) fuzzy model-based method is proposed to deal with the problem of synchronization of two identical or different hyperchaotic systems. The T S fuzzy models with a small number of fuzzy IF-THEN rules are employed to represent many typical hyperchaotic systems exactly. The benefit of employing the T-S fuzzy models lies in mathematical simplicity of analysis. Based on the T-S fuzzy hyperchaotic models, two fuzzy controllers arc designed via parallel distributed compensation (PDC) and exact linearization (EL) techniques to synchronize two identical hyperchaotic systems with uncertain parameters and two different hyperchaotic systems, respectively. The sufficient conditions for the robust synchronization of two identical hyperchaotic systems with uncertain parameters and the asymptotic synchronization of two different hyperchaotic systems are derived by applying the Lyapunov stability theory. This method is a universal one of synchronizing two identical or different hyperchaotic systems. Numerical examples are given to demonstrate the validity of the proposed fuzzy model and hyperchaotic synchronization scheme. 相似文献