Nonlinear Dynamics of Chaotic Attractor of Chua Circuit and Its Application for Secure Communication

The Chua circuit is among the simplest non-linear circuits that shows most complex dynamical behavior, including chaos which exhibits a variety of bifurcation phenomena and attractors. In this paper, Chua attractor's chaotic oscillator, synchronization and masking communication circuits were designed and simulated. The electronic circuit oscilloscope outputs of the realized Chua system is also presented. Simulation and oscilloscope outputs are used to illustrate the accuracy of the designed and realized Chua chaotic oscillator circuits. The Chua system is addressed suitable for chaotic synchronization circuits and chaotic masking communication circuits using Matlab® and MultiSIM® software. Simulation results are used to visualize and illustrate the effectiveness of Chua chaotic system in synchronization and application of secure communication.  Keywords: chua nonlinear circuit, chaotic attractor, chaotic synchronization, secure communication

STRUKTUR MODAL DAN KEPUTUSAN INVESTASI PADA PERUSAHAAN TELEKOMUNIKASI INDONESIA

This study aimed to explore the interconnection of capital structure and investment decisions based on therelationship between corporate leverage and investment options. The samples used were telecommunicationcompanies in Indonesia which had already become public companies from 2006 to 2013. The data was processedby using multiple regression technique and t test and F test to see the difference of investment source.This study revealed that an increase in the firm value as a result of an increase in the debts of the company andits increase was different between the companies that the investment came from foreign investment and localinvestment. Investment selection by using the debt was considered to be the correct choice made by management.The value of the company was obtained better by companies that used local investment. Telecommunicationbusiness was still considered by investors to be the prospective industries