Browsing by Author "Juang, J"

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A synchronization scheme using self-pulsating laser diodes in optical chaotic communication
(2000-03-01)
Juang, C
;
Hwang, TM
;
Juang, J
;
Lin, WW
;
應用數學系
A synchronization scheme using self-pulsating laser diodes in optical chaotic communication is proposed. Optical chaotic light can be obtained by injecting a sinusoidal electronic signal into a self-pulsating laser diode. To synchronize between two identical chaotic systems with different initial conditions, a drive and response system model is constructed according to Pecora and Carroll's theory. Synchronization can be achieved for optical simplex and duplex transmissions provided that the conditional Lyapunov exponents for the drive and response systems are all negative. This approach offers a key step toward realizing optical chaotic modulation and demodulation.
Cellular neural networks: Local patterns for general templates
(2000-07-01)
Hsu, CH
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Juang, J
;
Lin, SS
;
Lin, WW
;
應用數學系
This work investigates the mosaic local patterns for cellular neural networks with general templates. Our results demonstrate that the set of templates can be divided into many finite regions. In each region, the same family of local patterns can be generated. Conversely, our results further demonstrate that some templates can realize a family of local patterns which can be linearly separated by a hyperplane in the configuration space. This study also proposes algorithms for verifying the linear separability for a given family of local patterns and, when it is separable, for obtaining the associated template.
Cellular neural networks: Mosaic pattern and spatial chaos
(2000-03-21)
Juang, J
;
Lin, SS
;
應用數學系
;
Department of Applied Mathematics
We consider a cellular neural network (CNN) with a bias term z in the integer lattice Z(2) on the plane R-2. We impose a symmetric coupling between nearest neighbors, and also between next-nearest neighbors. Two parameters, a and epsilon, are used to describe the weights between such interacting cells. We study patterns that can exist as stable equilibria. In particular, the relationship between mosaic patterns and the parameter space (z, a; epsilon) can be completely characterized. This, in turn, addresses the so-called learning problem in CNNs. The complexities of mosaic patterns are also addressed.
Cellular neural networks: Mosaic patterns, bifurcation and complexity
(2006-01-01)
Juang, J
;
Li, CL
;
Liu, MH
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應用數學系
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Department of Applied Mathematics
We study a one-dimensional Cellular Neural Network with an output function which is nonflat at infinity. Spatial chaotic regions are completely characterized. Moreover, each of their exact corresponding entropy is obtained via the method of transition matrices. We also study the bifurcation phenomenon of mosaic patterns with bifurcation parameters z and beta. Here z is a source (or bias) term and beta is the interaction weight between the neighboring cells. In particular, we find that by in.jecting the source term, i.e. z not equal 0,a lot of new chaotic patterns emerge with a smaller interaction weight beta. However, as beta increases to a certain range, most of previously observed chaotic patterus disappear, while other new chaotic patterns emerge.
Cellular neural networks: Space-dependent template, mosaic patterns and spatial chaos
(2002-08-01)
Juang, J
;
Shieh, SF
;
Turyn, L
;
應用數學系
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Department of Applied Mathematics
We consider a Cellular Neural Network (CNN) with a bias term in the integer lattice Z(2) on the plane Z(2). We impose a space-dependent coupling (template) appropriate for CNN in the hexagonal lattice on Z(2). Stable mosaic patterns of such CNN are completely characterized. The spatial entropy of a (p(1), p(2))-translation invariant set is proved to be well-defined and exists. Using such a theorem, we are also able to address the complexities of resulting mosaic patterns.
Chaotic behavior of hole mixing tunneling in asymmetric coupled quantum wells
(1997-02-01)
Juang, C
;
Tsai, CB
;
Juang, J
;
應用數學系
;
Department of Applied Mathematics
Coherent oscillatory motion of hole mixing tunneling in asymmetric coupled quantum well structures collapses if the heavy hole state in the first well is aligned with the light hole state in the second well under a significant in-plane vector k(parallel to). The tunneling probability obtained by the time-dependent Schrodinger operator with the Luttinger Hamiltonian in the oscillation collapse region is shown to be a chaotic time series using the simplex projection method. This effect is attributed to the nonlinear interaction of mixing tunnelings between HH to the LH state in the first well and HH to the LH state in the second well. (C) 1997 Elsevier Science Ltd.
Chaotic behavior of hole mixing tunneling in asymmetric coupled quantum wells
(1997-02-01)
Juang, C
;
Tsai, CB
;
Juang, J
;
應用數學系
;
Department of Applied Mathematics
Coherent oscillatory motion of hole mixing tunneling in asymmetric coupled quantum well structures collapses if the heavy hole state in the first well is aligned with the light hole state in the second well under a significant in-plane vector k(parallel to). The tunneling probability obtained by the time-dependent Schrodinger operator with the Luttinger Hamiltonian in the oscillation collapse region is shown to be a chaotic time series using the simplex projection method. This effect is attributed to the nonlinear interaction of mixing tunnelings between HH to the LH state in the first well and HH to the LH state in the second well. (C) 1997 Elsevier Science Ltd.
Chaotic behaviors of bistable laser diodes and its application in synchronization of optical communication
(2001-10-01)
Wang, WC
;
Hwang, TM
;
Juang, C
;
Juang, J
;
Liu, CY
Period-doubling routes to chaos behavior in bistable laser diodes is examined numerically, An external sinusoidal electronic drive is injected to generate chaotic light output. Phase portrait, Poincare map, bifurcation diagram, and Lyapunov exponent are then calculated to assert the existence of chaos. Furthermore, according to Pecora and Carroll's theory, a drive-response system is constructed by using the bistable laser diodes to mask the sinusoidal electronic signal with chaotic light. Synchronization can be achieved for optical simplex and duplex transmissions using bistable laser diodes. The proposed synchronization scheme between two separate chaotic systems provides a key step toward optical chaotic communication.
Charge oscillations in coupled quantum wells
(1997-04-01)
Juang, C
;
Tsai, CB
;
Juang, J
;
應用數學系
;
Department of Applied Mathematics
A study of charge oscillations due to electron- and hole-coherent, and mixing tunnelling in coupled quantum well structures is given. The time-dependent picture of coherent tunnelling of an electron and hole wave packet is obtained by the application of the time-development operator of the time-depsndent Schrodinger equation, and the time-dependent Schrodinger equation with the Luttinger Hamiltonian. Detailed physical mechanisms involving resonant coherent tunnelling on electrons, valence-band mixing effects on heavy- and light-hole tunnelling, spatial and mixing multiple tunnelling effects, in coupled quantum wells are described.
Charge oscillations in coupled quantum wells
(1997-04-01)
Juang, C
;
Tsai, CB
;
Juang, J
;
應用數學系
;
Department of Applied Mathematics
A study of charge oscillations due to electron- and hole-coherent, and mixing tunnelling in coupled quantum well structures is given. The time-dependent picture of coherent tunnelling of an electron and hole wave packet is obtained by the application of the time-development operator of the time-depsndent Schrodinger equation, and the time-dependent Schrodinger equation with the Luttinger Hamiltonian. Detailed physical mechanisms involving resonant coherent tunnelling on electrons, valence-band mixing effects on heavy- and light-hole tunnelling, spatial and mixing multiple tunnelling effects, in coupled quantum wells are described.
Controlling chaotic behavior of heavy to light hole mixing tunneling by external electric fields
(1997-08-01)
Juang, C
;
Wang, JY
;
Juang, J
;
應用數學系
;
Department of Applied Mathematics
Oscillatory and chaotic motion of heavy to light hole mixing tunneling in asymmetric coupled quantum-well structures can be controlled by an external electric field. Chaotic behavior occurs if the heavy-hole state in the first well is aligned with the light-hole state in the second well under a significant in-plane vector k(parallel to). Oscillatory motion is recovered if the external electric field disrupts the alignment between the heavy-hole state in the first well and the light-hole state in the second well.
Eigenvalue problems for one-dimensional discrete Schrodinger operators with symmetric boundary conditions
(2001-11-19)
Juang, J
;
Lin, WW
;
Shieh, SF
;
應用數學系
;
Department of Applied Mathematics
In this paper, we investigate the one-dimensional discrete Schrodinger equation with general, symmetric boundary conditions. Our results primarily concern the number of energy states lying in the wells.
Existence for a matrix equation arising in microelectronics
(1996-11-01)
Juang, J
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交大名義發表
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應用數學系
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National Chiao Tung University
;
Department of Applied Mathematics
In this paper we rigorously show the existence of solutions of a matrix equation which arises in the design of micro electronical circuits. This equation was studied by Szidarovszky and Palusinsk [Appl. Math. Comput. 64, 115-119(1994)], who also presented an iterative algorithm for its solution. We show, via an example, that this algorithm could converge extremely slow in certian cases. The solution can then be used to minimize the reflection coefficients of the active signals.
FM detection from an optical chaotic carrier
(2001-07-01)
Huang, ST
;
Hwang, TM
;
Juang, C
;
Juang, J
;
Lin, WW
To synchronize two identical chaotic systems with different initial conditions, a drive and response system model is constructed according to Pecora and Carroll's theory. The drive and response systems become asymptotically synchronized if an FM signal is added to the drive system. The FM signal can be detected when the drive and response systems are strongly coupled.
Global existence and stability of solutions of matrix riccati equations
(2001-06-01)
Juang, J
;
應用數學系
;
Department of Applied Mathematics
We consider a matrix Riccati equation containing two parameters C and cu. The quantity c denotes the average total number of particles emerging from a collision, which is assumed to be conservative (i.e., 0 < c less than or equal to 1), and alpha (0 less than or equal to alpha < 1) is an angular shift. Let S = {(c, alpha):0 < c 1 and 0 alpha < 1}. Stability analysis for two steady-state solutions X-min and X-max are provided. In particular, we prove that X-min is locally asymptotically stable for S - {(1, 0)}, while X-max is unstable for S - {(1, 0)}. For c = 1 and alpha = 0, X-min = X-max is neutral stable. We also show that such equations have a global positive solution for (c, cu) E S, provided that the initial value is small and positive. (C) 2001 Academic Press.
Multiple tunneling and chaos in asymmetrically coupled quantum wells
(1999-11-01)
Juang, C
;
Lee, GY
;
Juang, J
;
應用數學系
;
Department of Applied Mathematics
Oscillatory and chaotic motion of heavy to light hole mixing tunneling in asymmetrically coupled quantum well structures is determined by two competing processes: HHa to LHa and HHa to LHb. Chaotic behavior occurs if the two processes ale compatible. Oscillatory motion is recovered if one process is dominant. The effects of barrier width, external field, and in-plane wave factor kit on each process are addressed.
Nonlinear dynamics of self-pulsating laser diodes under external drive
(1999-10-01)
Juang, C
;
Chen, MR
;
Juang, J
;
應用數學系
;
Department of Applied Mathematics
A self-pulsating laser diode under external drive shows the nonlinear dynamical effects of two competing frequencies. One can establish a route to chaos by increasing the modulation current. However, when the modulation frequency is varied, the chaotic state is suddenly destroyed at the harmonic frequencies of the self-pulsating frequency. This approach therefore offers a simple chaotic light source for possible optical chaotic communication. (C) 1999 Optical Society of America.
Nonsymmetric algebraic Riccati equations and Hamiltonian-like matrices
(1998-09-22)
Juang, J
;
Lin, WW
;
應用數學系
;
Department of Applied Mathematics
We consider a nonsymmetric algebraic matrix Riccati equation arising from transport theory. The nonnegative solutions of the equation can be explicitly constructed via the inversion formula of a Cauchy matrix. An error analysis and numerical results are given. We also show a comparison theorem of the nonnegative solutions.
Nonsymmetric algebraic Riccati equations and Hamiltonian-like matrices
(1998-09-22)
Juang, J
;
Lin, WW
;
應用數學系
;
Department of Applied Mathematics
We consider a nonsymmetric algebraic matrix Riccati equation arising from transport theory. The nonnegative solutions of the equation can be explicitly constructed via the inversion formula of a Cauchy matrix. An error analysis and numerical results are given. We also show a comparison theorem of the nonnegative solutions.
On the spatial entropy of two-dimensional golden mean
(2004-01-01)
Juang, J
;
Shieh, SF
;
應用數學系
;
Department of Applied Mathematics
The aim of this paper is to derive a sharper lower bound for the spatial entropy of two-dimensional golden mean.