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Design of spread-spectrum sequences using chaotic dynamical systems and ergodic theory
A new design methodology for the design of optimal spread-spectrum sequences for asynchronous code-division multiple access (A-CDMA) and chip-synchronous CDMA (CS-CDMA) systems is proposed. We deriveExpand
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METHOD OF CONSTRUCTING EXACTLY SOLVABLE CHAOS
  • K. Umeno
  • Physics, Mathematics
  • 3 October 1996
We present a new systematic method of constructing rational mappings as ergordic transformations with nonuniform invariant measures on the unit interval [0,1]. As a result, we obtain a two-parameterExpand
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Chaotic Monte Carlo Computation: A Dynamical Effect of Random-Number Generations
  • K. Umeno
  • Physics, Mathematics
  • 10 December 1998
Chaotic maps with absolutely continuous invariant probability measures are implemented as random-number generators for Monte Carlo computation. We observe that such Monte Carlo computation based onExpand
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Blind source separation of chaotic laser signals by independent component analysis.
We experimentally demonstrate blind source separation of chaos generated in Nd:YVO(4) microchip solid-state lasers by using independent component analysis. Two chaotic source signals are linearlyExpand
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Corrections of the NIST Statistical Test Suite for Randomness
It is well known that the NIST statistical test suite was used for the evaluation of AES candidate algorithms. We have found that the test setting of Discrete Fourier Transform test and Lempel-ZivExpand
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Spreading sequences using periodic orbits of chaos for CDMA
A new family of spreading sequences, which are generated by periodic points of a special class of chaotic dynamics, is discovered. It is shown that the chaotic sequences can have better correlationExpand
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Non-integrable character of Hamiltonian systems with global and symmetric coupling
Abstract A new sufficient condition to prove non-integrability of Hamiltonian systems with symmetric variational equations is proposed. Though the present condition is taken as an extension of ZiglinExpand
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Hippocampal place cell activity during chasing of a moving object associated with reward in rats
Hippocampal place cells encode location of animals in the environment. However, it remains unknown whether the hippocampal place cells encode a continuously moving object in the environment. ToExpand
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Higher-Order Decomposition Theory of Exponential Operators and Its Applications to QMC and Nonlinear Dynamics
A general theory of higher-order decomposition of exponential operators and symplectic integrators is reviewed briefly. Some explicit formulas are given up to the tenth order. An application of theseExpand
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