الفهرس 
Overview on dynamical and chaotic systemsOnly 14 pages are availabe for public view
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Abstract
The main objective of this thesis is to exploit the rich dynamics of chaos in designing a universal gate capable of performing all logic functions using the same topology as well as the same component values.
We introduce a review on chaotic systems, chaos set on, systems displaying chaos in mechanics, fluids, weather, biology,’ and electronics. Chaos manifests itself in strange Ittractors in phase space, unrepeatable time response with fundamental periods, continuous emission spectrum, and positive Lyapunov exponent. (Lyapunov exponent measures the average exponential convergence or divergence in phase space).
A study of chaotic systems including discrete and continuous time systems is also presented together with an answer to the questions of: how to design systems to posses cbaotic behavior?, how to increase the dynamic range of bifurcation from a given chaotic
ystem?, and how to retain system stability? The analysis is restricted to nonlinear systems mcluding one nonlinear element and a system dimension :s 3. As the dynamic range of bifurcation increases, the system is a candidate for chaogate realization (chaogate is a gate capable of performing all logic functions). Bifurcation diagrams are used to demonstrate regions of chaotic behavior and regions of periodic responses in the parameter space. This part is covered in Chapter 2.
The control of chaos is a key step in the design of chaogate. This includes, parametric tuning, damping method, data acquisition method and Pyrags method that utilizes both direct linear and time delayed feedback stabilization techniques. This part fmds many applications m secure communications that involve masking the transmitted information with a chaotic
ignal.
Mechanizing these methods with synchronization is achieved in Chapter 3. The ayochronization is obtained by coupling a robust periodic behavior resulting from a system baving a negative defmite Lyapunov exponent with chaotic system. This part fmds many Ipplications in biomedical engineering.
In Chapter 4, we introduce the idea of chaotic computing, exploiting the rich dyDamics of chaos, one can reconfigure the circuit to perform all logic functions such as AND, OR, XOR, NOT and NOR applications. This is achieved without altering the circuit topology or component values. Only a change takes place in the level defining the threshold. The definition of the threshold enables us to control the operation of the same circuit. Module cIIIogate circuits realized from discrete time and continuous time systems are introduced. 1bese have the advantages of simplicity, no requirement for state variable accessibility and switching between different operations.
Full adder functions are also provided. At the end of Chapters 2,3 and 4, a VHDL¬models were introduced to facilitate the chaogate synthesis.