258 research outputs found
Transition from anticipatory to lag synchronization via complete synchronization in time-delay systems
The existence of anticipatory, complete and lag synchronization in a single
system having two different time-delays, that is feedback delay and
coupling delay , is identified. The transition from anticipatory to
complete synchronization and from complete to lag synchronization as a function
of coupling delay with suitable stability condition is discussed. The
existence of anticipatory and lag synchronization is characterized both by the
minimum of similarity function and the transition from on-off intermittency to
periodic structure in laminar phase distribution.Comment: 14 Pages and 12 Figure
Nonlinear Dynamics of Moving Curves and Surfaces: Applications to Physical Systems
The subject of moving curves (and surfaces) in three dimensional space (3-D)
is a fascinating topic not only because it represents typical nonlinear
dynamical systems in classical mechanics, but also finds important applications
in a variety of physical problems in different disciplines. Making use of the
underlying geometry, one can very often relate the associated evolution
equations to many interesting nonlinear evolution equations, including soliton
possessing nonlinear dynamical systems. Typical examples include dynamics of
filament vortices in ordinary and superfluids, spin systems, phases in
classical optics, various systems encountered in physics of soft matter, etc.
Such interrelations between geometric evolution and physical systems have
yielded considerable insight into the underlying dynamics. We present a
succinct tutorial analysis of these developments in this article, and indicate
further directions. We also point out how evolution equations for moving
surfaces are often intimately related to soliton equations in higher
dimensions.Comment: Review article, 38 pages, 7 figs. To appear in Int. Jour. of Bif. and
Chao
Periodic energy switching of bright solitons in mixed coupled nonlinear Schr{\"o}dinger equations with linear self and cross coupling terms
The bright soliton solutions of the mixed 2-coupled nonlinear Schr{\"o}dinger
(CNLS) equations with linear self and cross coupling terms have been obtained
by identifying a transformation that transforms the corresponding equation to
the integrable mixed 2-CNLS equations. The study on the collision dynamics of
bright solitons shows that there exists periodic energy switching, due to the
coupling terms. This periodic energy switching can be controlled by the new
type of shape changing collisions of bright solitons arising in mixed 2-CNLS
system, characterized by intensity redistribution, amplitude dependent phase
shift and relative separation distance. We also point out that this system
exhibits large periodic intensity switching even with very small linear self
coupling strengths.Comment: Appeared in Physical Review
Recommended from our members
ILC Electron Source Injector Simuations
As part of the global project aimed at proposing an efficient design for the ILC (International Linear Collider), we simulated possible setups for the electron source injector, which will provide insight into how the electron injector for the ILC should be designed in order to efficiently accelerate the electron beams through the bunching system. This study uses three types of software: E-Gun to simulate electron beam emission, Superfish to calculate solenoidal magnetic fields, and GPT (General Particle Tracer) to trace charged particles after emission through magnetic fields and subharmonic bunchers. We performed simulations of the electron source injector using various electron gun bias voltages (140kV - 200kV), emitted beam lengths (500ps - 1ns) and radii (7mm - 10mm), and electromagnetic field strengths of the first subharmonic buncher (5 - 20 MV/m). The results of the simulations show that for the current setup of the ILC, a modest electron gun bias voltage ({approx}140kV) is sufficient to achieve the required bunching of the beam in the injector. Extensive simulations of parameters also involving the second subharmonic buncher should be performed in order to gain more insight into possible efficient designs for the ILC electron source injector
Gender assignment strategies among simultaneous Spanish/English bilingual children from Miami, Florida
Theoretical and Experimental Linguistic
A nonlocal connection between certain linear and nonlinear ordinary differential equations/oscillators
We explore a nonlocal connection between certain linear and nonlinear
ordinary differential equations (ODEs), representing physically important
oscillator systems, and identify a class of integrable nonlinear ODEs of any
order. We also devise a method to derive explicit general solutions of the
nonlinear ODEs. Interestingly, many well known integrable models can be
accommodated into our scheme and our procedure thereby provides further
understanding of these models.Comment: 12 pages. J. Phys. A: Math. Gen. 39 (2006) in pres
Highly sensitive capacitive pressure sensors for robotic applications based on carbon nanotubes and PDMS polymer nanocomposite
Flexible tactile pressure
sensor arrays based on multiwalled carbon nanotubes (MWCNT) and
polydimethylsiloxane (PDMS) are gaining importance, especially in the field
of robotics because of the high demand for stable, flexible and sensitive
sensors. Some existing concepts of pressure sensors based on nanocomposites
exhibit complicated fabrication techniques and better sensitivity than the
conventional pressure sensors. In this article, we propose a
nanocomposite-based pressure sensor that exhibits a high sensitivity of
25 % N−1, starting with a minimum
load range of 0–0.01 N and 46.8 % N−1 in the range of 0–1 N.
The maximum pressure sensing range of the sensor is approximately 570 kPa. A
concept of a 4×3
tactile sensor array, which could be integrated to robot fingers, is
demonstrated. The high sensitivity of the pressure sensor enables precision
grasping, with the ability to sense small objects with a size of 5 mm and a
weight of 1 g. Another application of the pressure sensor is demonstrated as
a gait analysis for humanoid robots. The pressure sensor is integrated under
the foot of a humanoid robot to monitor and evaluate the gait of the robot,
which provides insights for optimizing the robot's self-balancing algorithm
in order to maintain the posture while walking.</p
Computational studies on new Leishmanial drug targets against Quercetin
Leishmaniasis, a parasitic disease caused by Leishmania parasite which resides in the infected sand flies. Control of Leishmaniasis remains a source of grave concern worldwide. Studies on Leishmaniasis triggered because of its outbreak in tropical and subtropical regions of Asia, East Africa and South America. There is an urgent need for new therapeutic interventions such as vaccine and new drug targets as it develops resistance towards the available drugs. Quercetin, a derivative of polyphenolic flavonoid exhibits various biological activities by interacting with proteins and nucleic acids. In this study, computational analysis was performed to identify the potential drug target of Quercetin in Leishmania species by molecular docking. The newly predicted targets were subjected for subcellular localization prediction and determined the protein-protein interaction networks that would aid in the development of anti-Leishmanial drugs. This study helps in the identification of targets and development of anti-Leishmanial drugs
Exact soliton solutions, shape changing collisions and partially coherent solitons in coupled nonlinear Schroedinger equations
We present the exact bright one-soliton and two-soliton solutions of the
integrable three coupled nonlinear Schroedinger equations (3-CNLS) by using the
Hirota method, and then obtain them for the general -coupled nonlinear
Schroedinger equations (N-CNLS). It is pointed out that the underlying solitons
undergo inelastic (shape changing) collisions due to intensity redistribution
among the modes. We also analyse the various possibilities and conditions for
such collisions to occur. Further, we report the significant fact that the
various partial coherent solitons (PCS) discussed in the literature are special
cases of the higher order bright soliton solutions of the N-CNLS equations.Comment: 4 pages, RevTex, 1 EPS figure To appear in Physical Review Letter
Interruption of torus doubling bifurcation and genesis of strange nonchaotic attractors in a quasiperiodically forced map : Mechanisms and their characterizations
A simple quasiperiodically forced one-dimensional cubic map is shown to
exhibit very many types of routes to chaos via strange nonchaotic attractors
(SNAs) with reference to a two-parameter space. The routes include
transitions to chaos via SNAs from both one frequency torus and period doubled
torus. In the former case, we identify the fractalization and type I
intermittency routes. In the latter case, we point out that atleast four
distinct routes through which the truncation of torus doubling bifurcation and
the birth of SNAs take place in this model. In particular, the formation of
SNAs through Heagy-Hammel, fractalization and type--III intermittent mechanisms
are described. In addition, it has been found that in this system there are
some regions in the parameter space where a novel dynamics involving a sudden
expansion of the attractor which tames the growth of period-doubling
bifurcation takes place, giving birth to SNA. The SNAs created through
different mechanisms are characterized by the behaviour of the Lyapunov
exponents and their variance, by the estimation of phase sensitivity exponent
as well as through the distribution of finite-time Lyapunov exponents.Comment: 27 pages, RevTeX 4, 16 EPS figures. Phys. Rev. E (2001) to appea
- …