Uğur Erkin Kocamaz

Synchronization and control of chaos in supply chain management

Chaos in supply chain management is described.Active controllers are applied for the synchronization.Linear feedback controllers are applied for the control.Lyapunov function is used to realize synchronization and control.Computer simulations verify the effectiveness of synchronization and control methods. This paper presents the synchronization and control of a chaotic supply chain management system based on its mathematical model. For this purpose, active controllers are applied for the synchronization of two identical chaotic supply chain management systems. Also, linear feedback controllers are designed and added to the nonlinear supply chain management system to achieve the control of the system. In these methods, synchronization and control are established by using Lyapunov stability theory. As a result, the synchronization and control of chaotic supply chain management system are realized numerically. Computer simulations are performed to verify the robustness of proposed synchronization and control methods.

Synchronization and Electronic Circuit Application of Hidden Hyperchaos in a Four-Dimensional Self-Exciting Homopolar Disc Dynamo without Equilibria

We introduce and investigate a four-dimensional hidden hyperchaotic system without equilibria, which is obtained by augmenting the three-dimensional self-exciting homopolar disc dynamo due to Moffatt with an additional control variable. Synchronization of two such coupled disc dynamo models is investigated by active control and sliding mode control methods. Numerical integrations show that sliding mode control provides a better synchronization in time but causes chattering. The solution is obtained by switching to active control when the synchronization errors become very small. In addition, the electronic circuit of the four-dimensional hyperchaotic system has been realized in ORCAD-PSpice and on the oscilloscope by amplitude values, verifying the results from the numerical experiments.

Secure Communication with Chaos and Electronic Circuit Design Using Passivity-Based Synchronization

This work deals with the passive control-based chaos synchronization with circuit design for secure communication. First, the numerical simulation and electronic circuit design of a simple five-term chaotic system are performed. The numerical simulation and electronic circuit design outputs have confirmed each other. Then, the passive control method is applied for synchronizing two identical five-term chaotic systems using only one state control signal. After the synchronization study, design and analysis for secure communication by chaotic masking method are conducted in Matlab–Simulink platform. Finally, an electronic circuit design is performed for the designed communication system. In the designed communication system with Matlab–Simulink platform and electronic circuit design, information signal which is sent from the transmitter unit is successfully retrieved at the receiver unit. As a result, the electronic circuit design has shown that a single state passivity-based synchronization signal can be effectively used for secure data communication applications for the real environment.

Non-Identical Synchronization, Anti-Synchronization and Control of Single-Machine Infinite-Bus Power System via Active Control

Since the idea of synchronizing two identical chaotic systems under different initial conditions was first introduced by Pecora and Carroll, the synchronization of chaotic systems has attracted much attention, and the synchronization of non-identical chaotic systems has also been investigated. Single-Machine Infinite-Bus (SMIB) power system has nonlinear behaviour. On account of avoiding undesirable behaviours in power systems such as voltage collapse, the synchronization and control of SMIB power system have considerable importance. This paper presents chaos synchronization and anti-synchronization of SMIB power system to Duffing oscillator by means of active control method. The sum of synchronization and anti-synchronization signals converge asymptotically to zero and achieve the control of SMIB power system. Numerical simulations are used to demonstrate the validity of proposed active control method on the non-identical synchronization, anti-synchronization and control of SMIB power system. DOI: http://dx.doi.org/10.5755/j01.itc.43.2.4677

Control and synchronization of chaotic supply chains using intelligent approaches

Intelligent control and synchronization of chaotic supply chain are applied.Artificial neural networks based controllers are used for the control.Adaptive neuro-fuzzy inference system based controllers are used for synchronization.Linear feedback and active control signals are also used.Computer simulations show that the proposed approach is very effective. This paper presents the control of chaotic supply chain with Artificial Neural Network (ANN) based controllers and the synchronization of two identical chaotic supply chains that have different initial conditions with Adaptive Neuro-Fuzzy Inference System (ANFIS) based controllers. A hybrid intelligent control model is designed in which the linear feedback and active control signals are also used for achieving the control and synchronization, respectively. ANN and ANFIS controllers are trained according to the model. Thereby, the advantages of classical and intelligent control methods are combined. Computer simulations show that the proposed approach is very effective for the control and synchronization of chaos in supply chain systems.

Controlling Hyperchaotic Finance System with Combining Passive and Feedback Controllers

In this paper, a novel control method that combines passive, linear feedback, and dislocated feedback control methods is proposed and applied to the control of the four-dimensional hyperchaotic finance system which has been introduced and controlled with the linear feedback and speed feedback control methods by Yu, Cai, and Li (2012). The stability of the hyperchaotic finance system at its equilibrium points is ensured on the basis of a Lyapunov function. Computer simulations are used for verifying all the theoretical analyses visually. In the simulations, the proposed control method is also compared with the speed feedback and linear feedback control methods to observe its effectiveness and the results are discussed. DOI: http://dx.doi.org/10.5755/j01.itc.47.1.16898

Control of Shimizu–Morioka Chaotic System with Passive Control, Sliding Mode Control and Backstepping Design Methods: A Comparative Analysis

This chapter investigates the control of continuous time Shimizu–Morioka chaotic system with unknown system parameters by means of three different control approaches, namely passive control, sliding mode control and backstepping design. Based on the properties of sliding mode control theory, the appropriate surfaces are designed. Lyapunov functions are used to realize that the passive controller and backstepping controllers ensure the global asymptotic stability of the system. Owing to the controllers, the Shimizu–Morioka chaotic system stabilizes towards its equilibrium points in the state space. Numerical simulations are performed to show and compare the efficiency of the proposed control methods.