Single-peak solitary wave solutions for the variant Boussinesq ...
Indian Academy of Sciences (India)
∈ H1 loc(R). (iii) Similar to the proof of the above (ii),we omit it here. This completes the proof. 3. Smooth and cusped single-peak solitary wave solutions. Theorem 2.4 gives a classification for all single-peak solitary wave solutions for eq. (2.4).
Grimshaw, RHJ
2007-01-01
After the initial observation by John Scott Russell of a solitary wave in a canal, his insightful laboratory experiments and the subsequent theoretical work of Boussinesq, Rayleigh and Korteweg and de Vries, interest in solitary waves in fluids lapsed until the mid 1960's with the seminal paper of Zabusky and Kruskal describing the discovery of the soliton. This was followed by the rapid development of the theory of solitons and integrable systems. At the same time came the realization that solitary waves occur naturally in many physical systems, and play a fundamental role in many circumstances. The aim of this text is to describe the role that soliton theory plays in fluids in several contexts. After an historical introduction, the book is divided five chapters covering the basic theory of the Korteweg-de Vries equation, and the subsequent application to free-surface solitary waves in water to internal solitary waves in the coastal ocean and the atmospheric boundary layer, solitary waves in rotating flows, ...
Solitary waves and homoclinic orbits
International Nuclear Information System (INIS)
Balmforth, N.J.
1994-03-01
The notion that fluid motion often organizes itself into coherent structures has increasingly permeated modern fluid dynamics. Such localized objects appear in laminar flows and persist in turbulent states; from the water on windows on rainy days, to the circulations in planetary atmospheres. This review concerns solitary waves in fluids. More specifically, it centres around the mathematical description of solitary waves in a single spatial dimension. Moreover, it concentrates on strongly dissipative dynamics, rather than integrable systems like the KdV equation. One-dimensional solitary waves, or pulses and fronts as they are also called, are the simplest kinds of coherent structure (at least from a geometrical point of view). Nevertheless, their dynamics can be rich and complicated. In some circumstances this leads to the formation of spatio-temporal chaos in the systems giving birth to the solitary waves, and understanding that phenomenon is one of the major goals in the theory outlined in this review. Unfortunately, such a goal is far from achieved to date, and the author assess its current status and incompleteness
Solitary waves and homoclinic orbits
Energy Technology Data Exchange (ETDEWEB)
Balmforth, N.J.
1994-03-01
The notion that fluid motion often organizes itself into coherent structures has increasingly permeated modern fluid dynamics. Such localized objects appear in laminar flows and persist in turbulent states; from the water on windows on rainy days, to the circulations in planetary atmospheres. This review concerns solitary waves in fluids. More specifically, it centres around the mathematical description of solitary waves in a single spatial dimension. Moreover, it concentrates on strongly dissipative dynamics, rather than integrable systems like the KdV equation. One-dimensional solitary waves, or pulses and fronts as they are also called, are the simplest kinds of coherent structure (at least from a geometrical point of view). Nevertheless, their dynamics can be rich and complicated. In some circumstances this leads to the formation of spatio-temporal chaos in the systems giving birth to the solitary waves, and understanding that phenomenon is one of the major goals in the theory outlined in this review. Unfortunately, such a goal is far from achieved to date, and the author assess its current status and incompleteness.
Brief communication: Multiscaled solitary waves
Derzho, Oleg G.
2017-11-01
It is analytically shown how competing nonlinearities yield multiscaled structures for internal solitary waves in stratified shallow fluids. These solitary waves only exist for large amplitudes beyond the limit of applicability of the Korteweg-de Vries (KdV) equation or its usual extensions. The multiscaling phenomenon exists or does not exist for almost identical density profiles. The trapped core inside the wave prevents the appearance of such multiple scales within the core area. The structural stability of waves of large amplitudes is briefly discussed. Waves of large amplitudes displaying quadratic, cubic and higher-order nonlinear terms have stable and unstable branches. Multiscaled waves without a vortex core are shown to be structurally unstable. It is anticipated that multiscaling phenomena will exist for solitary waves in various physical contexts.
Solitary waves in particle beams
International Nuclear Information System (INIS)
Bisognano, J.J.
1996-01-01
Since space charge waves on a particle beam exhibit both dispersive and nonlinear character, solitary waves or solitons are possible. Dispersive, nonlinear wave propagation in high current beams is found to be similar to ion-acoustic waves in plasmas with an analogy between Debye screening and beam pipe shielding. Exact longitudinal solitary wave propagation is found for potentials associated with certain transverse distributions which fill the beam pipe. For weak dispersion, the waves satisfy the Korteweg-deVries (KdV) equation, but for strong dispersion they exhibit breaking. More physically realizable distributions which do not fill the beam pipe are investigated and shown to also satisfy a KdV equation for weak dispersion if averaging over rapid transverse motion is physically justified. Scaling laws are presented to explore likely parameter regimes where these phenomena may be observed experimentally
Nonlinear positron acoustic solitary waves
International Nuclear Information System (INIS)
Tribeche, Mouloud; Aoutou, Kamel; Younsi, Smain; Amour, Rabia
2009-01-01
The problem of nonlinear positron acoustic solitary waves involving the dynamics of mobile cold positrons is addressed. A theoretical work is presented to show their existence and possible realization in a simple four-component plasma model. The results should be useful for the understanding of the localized structures that may occur in space and laboratory plasmas as new sources of cold positrons are now well developed.
Multi-component optical solitary waves
DEFF Research Database (Denmark)
Kivshar, Y. S.; Sukhorukov, A. A.; Ostrovskaya, E. A.
2000-01-01
We discuss several novel types of multi-component (temporal and spatial) envelope solitary waves that appear in fiber and waveguide nonlinear optics. In particular, we describe multi-channel solitary waves in bit-parallel-wavelength fiber transmission systems for highperformance computer networks......, multi-color parametric spatial solitary waves due to cascaded nonlinearities of quadratic materials, and quasiperiodic envelope solitons due to quasi-phase-matching in Fibonacci optical superlattices. (C) 2000 Elsevier Science B.V. All rights reserved....
Solitary-wave propagation and interactions for a sixth-order generalized Boussinesq equation
Directory of Open Access Journals (Sweden)
Bao-Feng Feng
2005-01-01
based on the phase plane analysis around the equilibrium point, is used to construct the solitary-wave solutions for this nonintegrable equation. A symmetric three-level implicit finite difference scheme with a free parameter θ is proposed to study the propagation and interactions of solitary waves. Numerical simulations show the propagation of a single solitary wave of SGBE, and two solitary waves pass by each other without changing their shapes in the head-on collisions.
CFD Analysis of Water Solitary Wave Reflection
Directory of Open Access Journals (Sweden)
K. Smida
2011-12-01
Full Text Available A new numerical wave generation method is used to investigate the head-on collision of two solitary waves. The reflection at vertical wall of a solitary wave is also presented. The originality of this model, based on the Navier-Stokes equations, is the specification of an internal inlet velocity, defined as a source line within the computational domain for the generation of these non linear waves. This model was successfully implemented in the PHOENICS (Parabolic Hyperbolic Or Elliptic Numerical Integration Code Series code. The collision of two counter-propagating solitary waves is similar to the interaction of a soliton with a vertical wall. This wave generation method allows the saving of considerable time for this collision process since the counter-propagating wave is generated directly without reflection at vertical wall. For the collision of two solitary waves, numerical results show that the run-up phenomenon can be well explained, the solution of the maximum wave run-up is almost equal to experimental measurement. The simulated wave profiles during the collision are in good agreement with experimental results. For the reflection at vertical wall, the spatial profiles of the wave at fixed instants show that this problem is equivalent to the collision process.
Solitary waves in dimer binary collision model
Ahsan, Zaid; Jayaprakash, K. R.
2017-01-01
Solitary wave propagation in nonlinear diatomic (dimer) chains is a very interesting topic of research in the study of nonlinear lattices. Such waves were recently found to be supported by the essentially nonlinear granular lattice and Toda lattice. An interesting aspect of this discovery is attributed to the realization of a spectrum of the mass ratio (the only system parameter governing the dynamics) that supports the propagation of such waves corresponding to the considered interaction potential. The objective of this exposition is to explore solitary wave propagation in the dimer binary collision (BC) model. Interestingly, the dimer BC model supports solitary wave propagation at a discrete spectrum of mass ratios similar to those observed in granular and Toda dimers. Further, we report a qualitative and one-to-one correspondence between the spectrum of the mass ratio corresponding to the dimer BC model and those corresponding to granular and Toda dimer chains.
Solitary wave propagation in solar flux tubes
International Nuclear Information System (INIS)
Erdelyi, Robert; Fedun, Viktor
2006-01-01
The aim of the present work is to investigate the excitation, time-dependent dynamic evolution, and interaction of nonlinear propagating (i.e., solitary) waves on vertical cylindrical magnetic flux tubes in compressible solar atmospheric plasma. The axisymmetric flux tube has a field strength of 1000 G at its footpoint, which is typical for photospheric regions. Nonlinear waves that develop into solitary waves are excited by a footpoint driver. The propagation of the nonlinear signal is investigated by solving numerically a set of fully nonlinear 2.0D magnetohydrodynamic (MHD) equations in cylindrical coordinates. For the initial conditions, axisymmetric solutions of the linear dispersion relation for wave modes in a magnetic flux tube are applied. In the present case, we focus on the sausage mode only. The dispersion relation is solved numerically for a range of plasma parameters. The equilibrium state is perturbed by a Gaussian at the flux tube footpoint. Two solitary solutions are found by solving the full nonlinear MHD equations. First, the nonlinear wave propagation with external sound speed is investigated. Next, the solitary wave propagating close to the tube speed, also found in the numerical solution, is studied. In contrast to previous analytical and numerical works, here no approximations were made to find the solitary solutions. A natural application of the present study may be spicule formation in the low chromosphere. Future possible improvements in modeling and the relevance of the photospheric chromospheric transition region coupling by spicules is suggested
Numerical Simulation of Cylindrical Solitary Waves in Periodic Media
Quezada de Luna, Manuel
2013-07-14
We study the behavior of nonlinear waves in a two-dimensional medium with density and stress relation that vary periodically in space. Efficient approximate Riemann solvers are developed for the corresponding variable-coefficient first-order hyperbolic system. We present direct numerical simulations of this multiscale problem, focused on the propagation of a single localized perturbation in media with strongly varying impedance. For the conditions studied, we find little evidence of shock formation. Instead, solutions consist primarily of solitary waves. These solitary waves are observed to be stable over long times and to interact in a manner approximately like solitons. The system considered has no dispersive terms; these solitary waves arise due to the material heterogeneity, which leads to strong reflections and effective dispersion.
Solitary waves on nonlinear elastic rods. I
DEFF Research Database (Denmark)
Sørensen, Mads Peter; Christiansen, Peter Leth; Lomdahl, P. S.
1984-01-01
Acoustic waves on elastic rods with circular cross section are governed by improved Boussinesq equations when transverse motion and nonlinearity in the elastic medium are taken into account. Solitary wave solutions to these equations have been found. The present paper treats the interaction between...
Electromagnetic solitary waves in magnetized plasmas
International Nuclear Information System (INIS)
Hazeltine, R.D.; Holm, D.D.; Morrison, P.J.
1985-03-01
A Hamiltonian formulation, in terms of noncanonical Poisson bracket, is presented for a nonlinear fluid system that includes reduced magnetohydrodynamics and the Hasegawa-Mima equation as limiting cases. The single-helicity and axisymmetric versions possess three nonlinear Casimir invariants, from which a generalized potential can be constructed. Variation of the generalized potential yields a description of exact nonlinear stationary states. The new equilibria, allowing for plasma flow as well as partial electron adiabaticity, are distinct from those found in conventional magnetohydrodynamic theory. They differ from electrostatic stationary states in containing plasma current and magnetic field excitation. One class of steady-state solutions is shown to provide a simple electromagnetic generalization of drift-solitary waves
On the solitary wave paradigm for tsunamis
DEFF Research Database (Denmark)
Madsen, Per A.; Fuhrman, David R.; Schäffer, Hemming Andreas
2008-01-01
Since the 1970s, solitary waves have commonly been used to model tsunamis especially in experimental and mathematical studies. Unfortunately, the link to geophysical scales is not well established, and in this work we question the geophysical relevance of this paradigm. In part 1, we simulate...... of finite amplitude solitary wave theory in laboratory studies of tsunamis. We conclude that order-of-magnitude errors in effective temporal and spatial duration occur when this theory is used as an approximation for long waves on a sloping bottom. In part 3, we investigate the phenomenon of disintegration...... of long waves into shorter waves, which has been observed e.g. in connection with the Indian Ocean tsunami in 2004. This happens if the front of the tsunami becomes sufficently steep, and as a result the front turns into an undular bore. We discuss the importance of these very short waves in connection...
Solitary wave collisions in the regularized long wave equation
Directory of Open Access Journals (Sweden)
Henrik Kalisch
2013-01-01
Full Text Available The regularized long-wave equation admits families of positive and negative solitary waves. Interactions of these waves are studied, and it is found that interactions of pairs of positive and pairs of negative solitary waves feature the same phase shift asymptotically as the wave velocities grow large as long as the same amplitude ratio is maintained. The collision of a positive with a negative wave leads to a host of phenomena, including resonance, annihilation and creation of secondary waves. A sharp criterion on the resonance for positive-negative interactions is found.
Interaction of solitary pulses in single mode optical fibres | Usman ...
African Journals Online (AJOL)
Two solitary waves launched, by way of incidence, into an optical fibre from a single pulse if the pulses are in-phase as understood from results of inverse scattering transform method applied to the cubic nonlinear Schrödinger equations, (CNLSE\\'s). The single CNLSE is then understood to describe evolution of coupled ...
Surf similarity and solitary wave runup
DEFF Research Database (Denmark)
Fuhrman, David R.; Madsen, Per A.
2008-01-01
to a previous parameterization, which was not given in an explicit form. Good coherency with experimental (breaking) runup data is preserved with this simpler parameter. A recasting of analytical (nonbreaking) runup expressions for sinusoidal and solitary waves additionally shows that they contain identical...
Solitary waves on nonlinear elastic rods. II
DEFF Research Database (Denmark)
Sørensen, Mads Peter; Christiansen, Peter Leth; Lomdahl, P. S.
1987-01-01
In continuation of an earlier study of propagation of solitary waves on nonlinear elastic rods, numerical investigations of blowup, reflection, and fission at continuous and discontinuous variation of the cross section for the rod and reflection at the end of the rod are presented. The results...
Bulk solitary waves in elastic solids
Samsonov, A. M.; Dreiden, G. V.; Semenova, I. V.; Shvartz, A. G.
2015-10-01
A short and object oriented conspectus of bulk solitary wave theory, numerical simulations and real experiments in condensed matter is given. Upon a brief description of the soliton history and development we focus on bulk solitary waves of strain, also known as waves of density and, sometimes, as elastic and/or acoustic solitons. We consider the problem of nonlinear bulk wave generation and detection in basic structural elements, rods, plates and shells, that are exhaustively studied and widely used in physics and engineering. However, it is mostly valid for linear elasticity, whereas dynamic nonlinear theory of these elements is still far from being completed. In order to show how the nonlinear waves can be used in various applications, we studied the solitary elastic wave propagation along lengthy wave guides, and remarkably small attenuation of elastic solitons was proven in physical experiments. Both theory and generation for strain soliton in a shell, however, remained unsolved problems until recently, and we consider in more details the nonlinear bulk wave propagation in a shell. We studied an axially symmetric deformation of an infinite nonlinearly elastic cylindrical shell without torsion. The problem for bulk longitudinal waves is shown to be reducible to the one equation, if a relation between transversal displacement and the longitudinal strain is found. It is found that both the 1+1D and even the 1+2D problems for long travelling waves in nonlinear solids can be reduced to the Weierstrass equation for elliptic functions, which provide the solitary wave solutions as appropriate limits. We show that the accuracy in the boundary conditions on free lateral surfaces is of crucial importance for solution, derive the only equation for longitudinal nonlinear strain wave and show, that the equation has, amongst others, a bidirectional solitary wave solution, which lead us to successful physical experiments. We observed first the compression solitary wave in the
Partial Differential Equations and Solitary Waves Theory
Wazwaz, Abdul-Majid
2009-01-01
"Partial Differential Equations and Solitary Waves Theory" is a self-contained book divided into two parts: Part I is a coherent survey bringing together newly developed methods for solving PDEs. While some traditional techniques are presented, this part does not require thorough understanding of abstract theories or compact concepts. Well-selected worked examples and exercises shall guide the reader through the text. Part II provides an extensive exposition of the solitary waves theory. This part handles nonlinear evolution equations by methods such as Hirota’s bilinear method or the tanh-coth method. A self-contained treatment is presented to discuss complete integrability of a wide class of nonlinear equations. This part presents in an accessible manner a systematic presentation of solitons, multi-soliton solutions, kinks, peakons, cuspons, and compactons. While the whole book can be used as a text for advanced undergraduate and graduate students in applied mathematics, physics and engineering, Part II w...
From bell-shaped solitary wave to W/M-shaped solitary wave ...
Indian Academy of Sciences (India)
These solitary wave solutions may be applied to neuroscience for providing a math- ematical model and explaining electrophysiological responses of visceral nociceptive neurons and sensitization of dorsal root reflexes [10]. The mathematical results we have obtained about the singular travelling wave equation provide a ...
Solitary wave and periodic wave solutions for Burgers, Fisher ...
Indian Academy of Sciences (India)
Home; Journals; Pramana – Journal of Physics; Volume 85; Issue 1. Solitary wave and periodic wave solutions for Burgers, Fisher, Huxley and combined forms of these equations by the (′/)-expansion method. Jalil Manafian Mehrdad Lakestani. Volume 85 Issue 1 July 2015 pp 31-52 ...
Solitary drift waves in the presence of magnetic shear
International Nuclear Information System (INIS)
Meiss, J.D.; Horton, W.
1982-07-01
The two-component fluid equations describing electron drift and ion acoustic waves in a nonuniform magnetized plasma are shown to possess nonlinear two-dimensional solitary wave solutions. In the presence of magnetic shear, radiative shear damping is exponentially small in L/sub s//L/sub n/ for solitary drift waves, in contrast to linear waves
Microtubules: A network for solitary waves
Directory of Open Access Journals (Sweden)
Zdravković Slobodan
2017-01-01
Full Text Available In the present paper we deal with nonlinear dynamics of microtubules. The structure and role of microtubules in cells are explained as well as one of models explaining their dynamics. Solutions of the crucial nonlinear differential equation depend on used mathematical methods. Two commonly used procedures, continuum and semi-discrete approximations, are explained. These solutions are solitary waves usually called as kink solitons, breathers and bell-type solitons. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III45010
Localization and solitary waves in solid mechanics
Champneys, A R; Thompson, J M T
1999-01-01
This book is a collection of recent reprints and new material on fundamentally nonlinear problems in structural systems which demonstrate localized responses to continuous inputs. It has two intended audiences. For mathematicians and physicists it should provide useful new insights into a classical yet rapidly developing area of application of the rich subject of dynamical systems theory. For workers in structural and solid mechanics it introduces a new methodology for dealing with structural localization and the related topic of the generation of solitary waves. Applications range from classi
Solitary plane waves in an isotropic hexagonal lattice
DEFF Research Database (Denmark)
Zolotaryuk, Yaroslav; Savin, A.V.; Christiansen, Peter Leth
1998-01-01
of these solitary waves is investigated numerically by their interactions with vacancies and lattice edges. Propagation of solitary plane waves through finite lattice domains with isotopic disorder is extensively studied. Comparison of these results with the soliton propagation in one-dimensional lattices with mass...
The solitary electromagnetic waves in the graphene superlattice
International Nuclear Information System (INIS)
Kryuchkov, Sergey V.; Kukhar', Egor I.
2013-01-01
d’Alembert equation written for the electromagnetic waves propagating in the graphene superlattice is analyzed. The possibility of the propagation of the solitary electromagnetic waves in the graphene superlattice is discussed. The amplitude and the width of the electromagnetic pulse are calculated. The drag current induced by such wave across the superlattice axis is investigated. The numerical estimate of the charge dragged by the solitary wave is made.
Comparison of bed shear under non-breaking and breaking solitary waves
Digital Repository Service at National Institute of Oceanography (India)
JayaKumar, S.; Baldock, T.E.
New experimental measurements of bed shear under solitary waves and solitary bores that represent tsunamis are presented. The total bed shear stress was measured directly using a shear cell apparatus. The solitary wave characteristics were measured...
Bed failure induced by internal solitary waves
Rivera-Rosario, Gustavo A.; Diamessis, Peter J.; Jenkins, James T.
2017-07-01
The pressure field inside a porous bed induced by the passage of an Internal Solitary Wave (ISW) of depression is examined using high-accuracy numerical simulations. The velocity and density fields are obtained by solving the Dubreil-Jacotin-Long Equation, for a two-layer, continuously stratified water column. The total wave-induced pressure across the surface of the bed is computed by vertically integrating for the hydrostatic and nonhydrostatic contributions. The bed is assumed to be a continuum composed of either sand or silt, with a small amount of trapped gas. Results show variations in pore-water pressure penetrating deeper into more conductive materials and remaining for a prolonged period after the wave has passed. In order to quantify the potential for failure, the vertical pressure gradient is compared against the buoyant weight of the bed. The pressure gradient exceeds this weight for weakly conductive materials. Failure is further enhanced by a decrease in bed saturation, consistent with studies in surface-wave induced failure. In deeper water, the ISW-induced pressure is stronger, causing failure only for weakly conductive materials. The pressure associated with the free-surface displacement that accompanies ISWs is significant, when the water depth is less than 100 m, but has little influence when it is greater than 100 m, where the hydrostatic pressure due to the pycnocline displacement is much larger. Since the pore-pressure gradient reduces the specific weight of the bed, results show that particles are easier for the flow to suspend, suggesting that pressure contributes to the powerful resuspension events observed in the field.
Directory of Open Access Journals (Sweden)
Kazantseva E.V.
2015-01-01
Full Text Available In a model which describes asymmetric oppositely directed nonlinear coupler it was observed in numerical simulations a phenomenon of solitary wave generation from the input constant continuous wave set at the entrance of a waveguide with negative refraction. The period of solitary wave formation decreases with increase of the continuum wave amplitude.
Diffractons: Solitary Waves Created by Diffraction in Periodic Media
Ketcheson, David I.
2015-03-31
A new class of solitary waves arises in the solution of nonlinear wave equations with constant impedance and no dispersive terms. These solitary waves depend on a balance between nonlinearity and a dispersion-like effect due to spatial variation in the sound speed of the medium. A high-order homogenized model confirms this effective dispersive behavior, and its solutions agree well with those obtained by direct simulation of the variable-coefficient system. These waves are observed to be long-time stable, globally attracting solutions that arise in general as solutions to nonlinear wave problems with periodically varying sound speed. They share some properties with known classes of solitary waves but possess important differences as well.
Dust acoustic solitary and shock waves in strongly coupled dusty ...
Indian Academy of Sciences (India)
between nonlinear and dispersion effects can result in the formation of symmetrical solitary waves. Also shock ... et al have studied the effect of nonadiabatic dust charge variation on the nonlinear dust acoustic wave with ..... Figure 5 presents the border between oscillatory- and monotonic-type shock waves as functions of ...
Solitary waves in a magneto-electro-elastic circular rod
International Nuclear Information System (INIS)
Xue, C X; Pan, E; Zhang, S Y
2011-01-01
A simple nonlinear model is proposed in this paper to study the solitary wave in a circular magneto-electro-elastic rod. Based on the constitutive relation for transversely isotropic piezoelectric and piezomagnetic materials, combined with the differential equations of motion, we derive the longitudinal wave motion equation in a long circular rod. The nonlinearity considered is geometrically associated with the nonlinear normal strain in the longitudinal rod direction and the transverse Poisson's effect is included by introducing the effective Poisson's ratio. The nonlinear solitary wave equation is solved by the Jacobi elliptic function expansion method and numerical examples demonstrate not only the existence of such a wave but also some interesting characteristics of the solitary wave in the rod made of different multiphase coupled materials
Solitary wave solutions of two-dimensional nonlinear Kadomtsev ...
Indian Academy of Sciences (India)
2017-09-13
Sep 13, 2017 ... Home; Journals; Pramana – Journal of Physics; Volume 89; Issue 3. Solitary wave solutions of ... Nonlinear two-dimensional Kadomtsev–Petviashvili (KP) equation governs the behaviour of nonlinear waves in dusty plasmas with variable dust charge and two temperature ions. By using the reductive ...
An efficient algorithm for computation of solitary wave solutions to ...
Indian Academy of Sciences (India)
2017-09-08
Sep 8, 2017 ... Nonlinear mathematical problems and their solutions attain much attention in solitary waves. In soliton theory, an efficient tool to attain various types of soliton solutions is the exp ( − φ ( ζ ) ) -expansion technique. This article is devoted to find exact travelling wave solutions of Drinfeld–Sokolov equation via a ...
An efficient algorithm for computation of solitary wave solutions to ...
Indian Academy of Sciences (India)
KAMRAN AYUB
2017-09-08
Sep 8, 2017 ... Abstract. Nonlinear mathematical problems and their solutions attain much attention in solitary waves. In soliton theory, an efficient tool to attain various types of soliton solutions is the exp(−ϕ(ζ))-expansion technique. This article is devoted to find exact travelling wave solutions of Drinfeld–Sokolov equation ...
Electron-acoustic solitary waves in the Earth's inner magnetosphere
Dillard, C. S.; Vasko, I. Y.; Mozer, F. S.; Agapitov, O. V.; Bonnell, J. W.
2018-02-01
The broadband electrostatic turbulence observed in the inner magnetosphere is produced by large-amplitude electrostatic solitary waves of generally two types. The solitary waves with symmetric bipolar parallel (magnetic field-aligned) electric field are electron phase space holes. The solitary waves with highly asymmetric bipolar parallel electric field have been recently shown to correspond to the electron-acoustic plasma mode (existing due to two-temperature electron population). Through theoretical and numerical analysis of hydrodynamic and modified Korteweg-de Vries equations, we demonstrate that the asymmetric solitary waves appear due to the steepening of initially quasi-monochromatic electron-acoustic perturbation arrested at some moment by collisionless dissipation (Landau damping). The typical steepening time is found to be from a few to tens of milliseconds. The steepening of the electron-acoustic waves has not been reproduced in self-consistent kinetic simulations yet, and factors controlling the formation of steepened electron-acoustic waves, rather than electron phase space holes, remain unclear.
Exact and explicit solitary wave solutions to some nonlinear equations
International Nuclear Information System (INIS)
Jiefang Zhang
1996-01-01
Exact and explicit solitary wave solutions are obtained for some physically interesting nonlinear evolutions and wave equations in physics and other fields by using a special transformation. These equations include the KdV-Burgers equation, the MKdV-Burgers equation, the combined KdV-MKdV equation, the Newell-Whitehead equation, the dissipative Φ 4 -model equation, the generalized Fisher equation, and the elastic-medium wave equation
Solitary wave solution to a singularly perturbed generalized Gardner ...
Indian Academy of Sciences (India)
2015-11-27
Home; Journals; Pramana – Journal of Physics; Volume 88; Issue 4. Solitary wave solution to a singularly perturbed generalized ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November 27, 2015. Guest Editors: ...
Solitary wave solution to a singularly perturbed generalized Gardner ...
Indian Academy of Sciences (India)
2017-03-24
Mar 24, 2017 ... which is one model in plasma physics and solid physics. [3]. Hamdi et al [4] obtained an exact solitary wave solution to eq. (1.2). They also derived three conserva- tion laws and three invariants of motion for eq. (1.2). [5]. Antonova and Biswas [6] exploited the soliton perturbation theory to eq. (1.2) with γ = 1.
Periodic and solitary wave solutions of cubic–quintic nonlinear ...
Indian Academy of Sciences (India)
physics pp. 1253–1258. Periodic and solitary wave solutions of cubic–quintic nonlinear reaction-diffusion equation with variable convection coefficients. S B BHARDWAJ1,2,∗ ... 3Department of Mathematics, National Institute of Technology, Delhi 110 040, India. 4Department of .... 3.1 Fractional transform soliton solutions.
An efficient algorithm for computation of solitary wave solutions to ...
Indian Academy of Sciences (India)
KAMRAN AYUB
2017-09-08
Sep 8, 2017 ... exact solitary wave solutions of nonlinear differential equations is a great achievement. In nonlinear physical sciences, an essential contribution is of exact solutions and because of this we can study physical behaviours and discus more features of the problem which give direction to more applications.
Quantum ion-acoustic solitary waves in weak relativistic plasma
Indian Academy of Sciences (India)
A linear dispersion relation is also obtained taking into account the relativistic effect. The properties of quantum ion-acoustic solitary waves, obtained from the deformed KdV equation, are studied taking into account the quantum mechanical effects in the weak relativistic limit. It is found that relativistic effects signiﬁcantly ...
Measurement and modeling of bed shear stress under solitary waves
Digital Repository Service at National Institute of Oceanography (India)
Jayakumar, S.; Guard, P.A.; Baldock, T.E.
Direct measurements of bed shear stresses (using a shear cell apparatus) generated by non-breaking solitary waves are presented. The measurements were carried out over a smooth bed in laminar and transitional flow regimes (~ 10 sup (4) < R sub (e...
Periodic and solitary wave solutions of cubic–quintic nonlinear ...
Indian Academy of Sciences (India)
odic, double-kink, bell and antikink-type solutions for cubic–quintic nonlinear reaction-diffusion equation are extracted. Such solutions can be used to explain various biological and physical phenomena. Keywords. Variable coefficient reaction-diffusion equation; solitary wave solution; cubic–quintic nonlinearity. PACS No.
Periodic and solitary wave solutions of cubic–quintic nonlinear ...
Indian Academy of Sciences (India)
Home; Journals; Pramana – Journal of Physics; Volume 86; Issue 6. Periodic and solitary wave solutions of cubic–quintic nonlinear reaction-diffusion equation with variable convection coefficients. BHARDWAJ S B SINGH RAM MEHAR SHARMA KUSHAL MISHRA S C. Regular Volume 86 Issue 6 June 2016 pp 1253-1258 ...
Quantum ion-acoustic solitary waves in weak relativistic plasma
Indian Academy of Sciences (India)
Abstract. Small amplitude quantum ion-acoustic solitary waves are studied in an unmagnetized two- species relativistic quantum plasma system, comprised of electrons and ions. The one-dimensional quantum hydrodynamic model (QHD) is used to obtain a deformed Korteweg–de Vries (dKdV) equation by reductive ...
Existence and Stability of Relativistic Solitary Waves in Warm Plasmas
International Nuclear Information System (INIS)
Maza-Palacios, Marco A.; Herrera-Velazquez, J. Julio E.
2006-01-01
A variational mehod for one dimensional relativistic solitons is established, within the two fluid model framework, including finite temperature effects. Our starting point is a Lagrangian for a two species fluid plasma, which allows the deduction of the conserved quantities of the system by means of Noether's theorem, as well as the model equations. At a first stage, travelling wave solutions are studied with the usual shape of envelope solitary waves. It is found that bounded travelling waves (bright solitons) exist for most velocities, if both ions and electrons are assumed to be relativistic, except for a window at small values of v/c. In order to study their stability, we obtain the evolution equations of the solitary wave parameters, along those of radiation
Elwakil, S. A.; Abulwafa, E. M.; El-Shewy, E. K.; Abd-El-Hamid, H. M.
2011-11-01
A theoretical investigation has been made for electron acoustic waves propagating in a system of unmagnetized collisionless plasma consists of a cold electron fluid and ions with two different temperatures in which the hot ions obey the non-thermal distribution. The reductive perturbation method has been employed to derive the Korteweg-de Vries equation for small but finite amplitude electrostatic waves. It is found that the presence of the energetic population of non-thermal hot ions δ, initial normalized equilibrium density of low temperature ions μ and the ratio of temperatures of low temperature ions to high temperature ions β do not only significantly modify the basic properties of solitary structure, but also change the polarity of the solitary profiles. At the critical hot ions density, the KdV equation is not appropriate for describing the system. Hence, a new set of stretched coordinates is considered to derive the modified KdV equation. In the vicinity of the critical hot ions density, neither KdV nor modified KdV equation is appropriate for describing the electron acoustic waves. Therefore, a further modified KdV equation is derived. An algebraic method with computerized symbolic computation, which greatly exceeds the applicability of the existing tanh, extended tanh methods in obtaining a series of exact solutions of the various KdV-type equations, is used here. Numerical studies have been reveals different solutions e.g., bell-shaped solitary pulses, singular solitary "blowup" solutions, Jacobi elliptic doubly periodic wave, Weierstrass elliptic doubly periodic type solutions, in addition to explosive pulses. The results of the present investigation may be applicable to some plasma environments, such as Earth's magnetotail region.
Existence of solitary waves in dipolar quantum gases
Antonelli, Paolo
2011-02-01
We study a nonlinear Schrdinger equation arising in the mean field description of dipolar quantum gases. Under the assumption of sufficiently strong dipolar interactions, the existence of standing waves, and hence solitons, is proved together with some of their properties. This gives a rigorous argument for the possible existence of solitary waves in BoseEinstein condensates, which originate solely due to the dipolar interaction between the particles. © 2010 Elsevier B.V. All rights reserved.
Slow solitary waves in multi-layered magnetic structures
International Nuclear Information System (INIS)
Ruderman, M.S.; Roberts, B.; Pelinovsky, E.N.; Petrukhin, N.S.
2001-01-01
The propagation of slow sausage surface waves in a multi-layered magnetic configuration is considered. The magnetic configuration consists of a central magnetic slab sandwiched between two identical magnetic slabs (with equilibrium quantities different from those in the central slab) which in turn are embedded between two identical semi-infinite regions. The dispersion equation is obtained in the linear approximation. The nonlinear governing equation describing waves with a characteristic wavelength along the central slab much larger than the slab thickness is derived. Solitary wave solutions to this equation are obtained in the case where these solutions deviate only slightly from the algebraic soliton of the Benjamin-Ono equation
Propagation of three-dimensional electron-acoustic solitary waves
Shalaby, M.; El-Labany, S. K.; Sabry, R.; El-Sherif, L. S.
2011-06-01
Theoretical investigation is carried out for understanding the properties of three-dimensional electron-acoustic waves propagating in magnetized plasma whose constituents are cold magnetized electron fluid, hot electrons obeying nonthermal distribution, and stationary ions. For this purpose, the hydrodynamic equations for the cold magnetized electron fluid, nonthermal electron density distribution, and the Poisson equation are used to derive the corresponding nonlinear evolution equation, Zkharov-Kuznetsov (ZK) equation, in the small- but finite- amplitude regime. The ZK equation is solved analytically and it is found that it supports both solitary and blow-up solutions. It is found that rarefactive electron-acoustic solitary waves strongly depend on the density and temperature ratios of the hot-to-cold electron species as well as the nonthermal electron parameter. Furthermore, there is a critical value for the nonthermal electron parameter, which decides whether the electron-acoustic solitary wave's amplitude is decreased or increased by changing various plasma parameters. Importantly, the change of the propagation angles leads to miss the balance between the nonlinearity and dispersion; hence, the localized pulses convert to explosive/blow-up pulses. The relevance of this study to the nonlinear electron-acoustic structures in the dayside auroral zone in the light of Viking satellite observations is discussed.
Propagation of three-dimensional electron-acoustic solitary waves
International Nuclear Information System (INIS)
Shalaby, M.; El-Sherif, L. S.; El-Labany, S. K.; Sabry, R.
2011-01-01
Theoretical investigation is carried out for understanding the properties of three-dimensional electron-acoustic waves propagating in magnetized plasma whose constituents are cold magnetized electron fluid, hot electrons obeying nonthermal distribution, and stationary ions. For this purpose, the hydrodynamic equations for the cold magnetized electron fluid, nonthermal electron density distribution, and the Poisson equation are used to derive the corresponding nonlinear evolution equation, Zkharov-Kuznetsov (ZK) equation, in the small- but finite- amplitude regime. The ZK equation is solved analytically and it is found that it supports both solitary and blow-up solutions. It is found that rarefactive electron-acoustic solitary waves strongly depend on the density and temperature ratios of the hot-to-cold electron species as well as the nonthermal electron parameter. Furthermore, there is a critical value for the nonthermal electron parameter, which decides whether the electron-acoustic solitary wave's amplitude is decreased or increased by changing various plasma parameters. Importantly, the change of the propagation angles leads to miss the balance between the nonlinearity and dispersion; hence, the localized pulses convert to explosive/blow-up pulses. The relevance of this study to the nonlinear electron-acoustic structures in the dayside auroral zone in the light of Viking satellite observations is discussed.
Rotating solitary wave at the wall of a cylindrical container
Amaouche, Mustapha
2013-04-30
This paper deals with the theoretical modeling of a rotating solitary surface wave that was observed during water drainage from a cylindrical reservoir, when shallow water conditions were reached. It represents an improvement of our previous study, where the radial flow perturbation was neglected. This assumption led to the classical planar Korteweg–de Vries equation for the wall wave profile, which did not account for the rotational character of the base flow. The present formulation is based on a less restricting condition and consequently corrects the last shortcoming. Now the influence of the background flow appears in the wave characteristics. The theory provides a better physical depiction of the unique experiment by predicting fairly well the wave profile at least in the first half of its lifetime and estimating the speed of the observed wave with good accuracy.
Optimal transient growth in thin-interface internal solitary waves
Passaggia, Pierre-Yves; Helfrich, Karl R.; White, Brian L.
2018-04-01
The dynamics of perturbations to large-amplitude Internal Solitary Waves (ISW) in two-layered flows with thin interfaces is analyzed by means of linear optimal transient growth methods. Optimal perturbations are computed through direct-adjoint iterations of the Navier-Stokes equations linearized around inviscid, steady ISWs obtained from the Dubreil-Jacotin-Long (DJL) equation. Optimal perturbations are found as a function of the ISW phase velocity $c$ (alternatively amplitude) for one representative stratification. These disturbances are found to be localized wave-like packets that originate just upstream of the ISW self-induced zone (for large enough $c$) of potentially unstable Richardson number, $Ri < 0.25$. They propagate through the base wave as coherent packets whose total energy gain increases rapidly with $c$. The optimal disturbances are also shown to be relevant to DJL solitary waves that have been modified by viscosity representative of laboratory experiments. The optimal disturbances are compared to the local WKB approximation for spatially growing Kelvin-Helmholtz (K-H) waves through the $Ri < 0.25$ zone. The WKB approach is able to capture properties (e.g., carrier frequency, wavenumber and energy gain) of the optimal disturbances except for an initial phase of non-normal growth due to the Orr mechanism. The non-normal growth can be a substantial portion of the total gain, especially for ISWs that are weakly unstable to K-H waves. The linear evolution of Gaussian packets of linear free waves with the same carrier frequency as the optimal disturbances is shown to result in less energy gain than found for either the optimal perturbations or the WKB approximation due to non-normal effects that cause absorption of disturbance energy into the leading face of the wave.
Stability of negative solitary waves for an integrable modified Camassa-Holm equation
International Nuclear Information System (INIS)
Yin Jiuli; Tian Lixin; Fan Xinghua
2010-01-01
In this paper, we prove that the modified Camassa-Holm equation is Painleve integrable. We also study the orbital stability problem of negative solitary waves for this integrable equation. It is shown that the negative solitary waves are stable for arbitrary wave speed of propagation.
A new model for algebraic Rossby solitary waves in rotation fluid and its solution
Chen, Yao-Deng; Yang, Hong-Wei; Gao, Yu-Fang; Yin, Bao-Shu; Feng, Xing-Ru
2015-09-01
A generalized Boussinesq equation that includes the dissipation effect is derived to describe a kind of algebraic Rossby solitary waves in a rotating fluid by employing perturbation expansions and stretching transformations of time and space. Using this equation, the conservation laws of algebraic Rossby solitary waves are discussed. It is found that the mass, the momentum, the energy, and the velocity of center of gravity of the algebraic solitary waves are conserved in the propagation process. Finally, the analytical solution of the equation is generated. Based on the analytical solution, the properties of the algebraic solitary waves and the dissipation effect are discussed. The results point out that, similar to classic solitary waves, the dissipation can cause the amplitude and the speed of solitary waves to decrease; however, unlike classic solitary waves, the algebraic solitary waves can split during propagation and the decrease of the detuning parameter can accelerate the occurrence of the solitary waves fission phenomenon. Project supported by the Shandong Provincial Key Laboratory of Marine Ecology and Environment and Disaster Prevention and Mitigation Project, China (Grant No. 2012010), the National Natural Science Foundation of China (Grant Nos. 41205082 and 41476019), the Special Funds for Theoretical Physics of the National Natural Science Foundation of China (Grant No. 11447205), and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), China.
Polarized seismic and solitary waves run-up at the sea bed
Energy Technology Data Exchange (ETDEWEB)
Dennis, L. C.C.; Zainal, A. A.; Faisal, S. Y. [Universiti Teknologi PETRONAS, 31750 Tronoh, Perak (Malaysia); Universiti Teknologi Malaysia, 81310 Johor Bahru (Malaysia)
2012-09-26
The polarization effects in hydrodynamics are studied. Hydrodynamic equation for the nonlinear wave is used along with the polarized solitary waves and seismic waves act as initial waves. The model is then solved by Fourier spectral and Runge-Kutta 4 methods, and the surface plot is drawn. The output demonstrates the inundation behaviors. Consequently, the polarized seismic waves along with the polarized solitary waves tend to generate dissimilar inundation which is more disastrous.
Linear Stability of the boundary layer under a solitary wave
Verschaeve, Joris C. G.; Pedersen, Geir K.
2013-01-01
A theoretical and numerical analysis of the linear stability of the boundary layer flow under a solitary wave is presented. In the present work, the nonlinear boundary layer equations are solved. The result is compared to the linear boundary layer solution in Liu et al. (2007) reveal- ing that both profiles are disagreeing more than has been found before. A change of frame of reference has been used to allow for a classical linear stability analysis without the need to redefine the notion of ...
Experiments and computation of onshore breaking solitary waves
DEFF Research Database (Denmark)
Jensen, A.; Mayer, Stefan; Pedersen, G.K.
2005-01-01
This is a combined experimental and computational study of solitary waves that break on-shore. Velocities and accelerations are measured by a two-camera PIV technique and compared to theoretical values from an Euler model with a VOF method for the free surface. In particular, the dynamics of a so......-called collapsing breaker is scrutinized and the closure between the breaker and the beach is found to be akin to slamming. To the knowledge of the authors, no velocity measurements for this kind of breaker have been previously reported....
Steffy, S. V.; Ghosh, S. S.
2017-10-01
The transition of an ion acoustic solitary wave into a "supersoliton," or a super solitary wave have been explored in a two electron temperature warm multi-ion plasma using the Sagdeev pseudopotential technique. It is generally believed that the ion acoustic solitary wave can be transformed to a super solitary wave only through a double layer. The present work shows that the transition route of an ion acoustic solitary wave to a super solitary wave is not unique. Depending on the electron temperature ratio, a regular solitary wave may transform to a super solitary wave either via the double layer, or through an extra-nonlinear solitary structure whose morphology differs from that of a regular one. These extra-nonlinear structures are associated with a fluctuation of the charge separation within the potential profile and are named as "variable solitary waves." Depending on these analyses, the upper and lower bounds of a super solitary wave have been deciphered and its existence domain has been delineated in the parametric space. It reveals that super solitary waves are a subset of a more generalized class of extra-nonlinear solitary structures called variable solitary waves.
Asymptotic expansions for solitary gravity-capillary waves in two and three dimensions
International Nuclear Information System (INIS)
Ablowitz, M J; Haut, T S
2010-01-01
High-order asymptotic series are obtained for gravity-capillary solitary waves, where the first term in the series is the well-known sech 2 solution of the KdV equation. The asymptotic series is used, with nine terms included, to investigate the effects of surface tension on the height and energy of large amplitude waves, and waves close to the solitary version of Stokes' extreme wave. In particular, for surface tension below a critical value, the solitary wave with the maximum energy is obtained. For large surface tension, the series is also used to study the energy related to the solitary waves of depression. Energy considerations suggest that, for large enough surface tension, there are solitary waves that can get close to the fluid bottom. Comparisons are also made with recent experiments.
Solitary Langmuir waves in two-electron temperature plasma
Prudkikh, V. V.; Prudkikh
2014-06-01
Nonlinear interaction of Langmuir and ion-acoustic waves in two-electron temperature plasma is investigated. New integrable wave interaction regime was discovered, this regime corresponds to the Langmuir soliton with three-hump amplitude, propagating with a speed close to the ion-sound speed in the conditions of strong non-isothermality of electronic components. It was discovered that besides the known analytical solution in the form of one- and two-hump waves, there exists a range of solutions in the form of solitary waves, which in the form of envelope has multi-peak structure and differs from the standard profiles described by hyperbolic functions. In case of fixed plasma parameters, different group velocities correspond to the waves with different number of peaks. It is found that the Langmuir wave package contains both even and uneven numbers of oscillations. Low-frequency potential here has uneven number of peaks. Interrelation of obtained and known earlier results are also discussed.
Solitary Waves of Ice Loss Detected in Greenland Crustal Motion
Adhikari, S.; Ivins, E. R.; Larour, E. Y.
2017-12-01
The annual cycle and secular trend of Greenland mass loading are well recorded in measurements of solid Earth deformation. While bedrock vertical displacements are in phase with loading as inferred from space observations, horizontal motions have received almost no attention. The horizontal bedrock displacements can potentially track the spatiotemporal detail of mass changes with great fidelity. Our analysis of Greenland crustal motion data reveals that a significant excitation of horizontal amplitudes occurs during the intense Greenland melting. A suite of space geodetic observations and climate reanalysis data cannot explain these large horizontal displacements. We discover that solitary seasonal waves of substantial mass transport traveled through Rink Glacier in 2010 and 2012. We deduce that intense summer melting enhanced either basal lubrication or shear softening, or both, causing the glacier to thin dynamically. The newly routed upstream sublglacial water was likely to be both retarded and inefficient, thus providing a causal mechanism for the prolonged ice transport to continue well into the winter months. As the climate continues to produce increasingly warmer spring and summer, amplified seasonal waves of mass transport may become ever more present in years of future observations. Increased frequency of amplified seasonal mass transport may ultimately strengthen the Greenland's dynamic ice mass loss, a component of the balance that will have important ramifications for sea level rise. This animation shows a solitary wave passing through Rink Glacier, Greenland, in 2012, recorded by the motion of a GPS station (circle with arrow). Darker blue colors within the flow indicate mass loss, red colors show mass gain. The star marks the center of the wave. Credit: NASA/JPL-Caltech
Complex dynamical behaviors of compact solitary waves in the perturbed mKdV equation
International Nuclear Information System (INIS)
Yin Jiu-Li; Xing Qian-Qian; Tian Li-Xin
2014-01-01
In this paper, we give a detailed discussion about the dynamical behaviors of compact solitary waves subjected to the periodic perturbation. By using the phase portrait theory, we find one of the nonsmooth solitary waves of the mKdV equation, namely, a compact solitary wave, to be a weak solution, which can be proved. It is shown that the compact solitary wave easily turns chaotic from the Melnikov theory. We focus on the sufficient conditions by keeping the system stable through selecting a suitable controller. Furthermore, we discuss the chaotic threshold for a perturbed system. Numerical simulations including chaotic thresholds, bifurcation diagrams, the maximum Lyapunov exponents, and phase portraits demonstrate that there exists a special frequency which has a great influence on our system; with the increase of the controller strength, chaos disappears in the perturbed system. But if the controller strength is sufficiently large, the solitary wave vibrates violently. (general)
Shoaling internal solitary waves of depression over gentle slopes
Rivera, Gustavo; Diamessis, Peter
2017-11-01
The shoaling of an internal solitary wave (ISW) of depression over gentle slopes is explored through fully nonlinear and non-hydrostatic simulations using a high resolution/accuracy deformed spectral multidomain penalty method. During shoaling, the wave does not disintegrate as in the case of steeper slope but, instead, maintains its symmetric shape. At the core of the wave, an unstable region forms, characterized by the entrapment of heavier-over-light fluid. The formation of this convective instability is attributed to the vertical stretching by the ISW of the near-surface vorticity layer associated with the baroclinic background current. According to recent field observations in the South China Sea, the unstable region drives localized turbulent mixing within the wave, estimated to be up to four times larger than that in the open ocean, in the form of a recirculating trapped core. In this talk, emphasis is placed on the structure of the unstable region and the persistence of a possible recirculating core using simulations which capture 2D wave propagation combined with 3D representation of the transition to turbulence. As such, a preliminary understanding of the underlying fluid mechanics and the potential broader oceanic significance of ISWs with trapped cores is offered. Financial support gratefully acknowledged to NSF OCE Grant 1634257.
Electrostatic solitary waves in dusty pair-ion plasmas
Energy Technology Data Exchange (ETDEWEB)
Misra, A. P. [Department of Mathematics, Siksha Bhavana, Visva-Bharati University, Santiniketan-731 235, West Bengal (India); Adhikary, N. C. [Physical Sciences Division, Institute of Advanced Study in Science and Technology, Vigyan Path, Paschim Boragaon, Garchuk, Guwahati-781035, Assam (India)
2013-10-15
The propagation of electrostatic waves in an unmagnetized collisionless pair-ion plasma with immobile positively charged dusts is studied for both large- and small-amplitude perturbations. Using a two-fluid model for pair-ions, it is shown that there appear two linear ion modes, namely the “fast” and “slow” waves in dusty pair-ion plasmas. The properties of these wave modes are studied with different mass (m) and temperature (T) ratios of negative to positive ions, as well as the effects of immobile charged dusts (δ). For large-amplitude waves, the pseudopotential approach is performed, whereas the standard reductive perturbation technique is used to study the small-amplitude Korteweg-de Vries (KdV) solitons. The profiles of the pseudopotential, the large amplitude solitons as well as the dynamical evolution of KdV solitons, are numerically studied with the system parameters as above. It is found that the pair-ion plasmas with positively charged dusts support the propagation of solitary waves (SWs) with only the negative potential. The results may be useful for the excitation of SWs in laboratory dusty pair-ion plasmas, electron-free industrial plasmas as well as for observation in space plasmas where electron density is negligibly small compared to that of negative ions.
Dynamical aspects of various solitary waves and double layers in dusty plasmas
Energy Technology Data Exchange (ETDEWEB)
Das, G.C. [Plasma Physics Division, Institute of Advanced Study in Science Technology, Khanapara, Guwahati-781022, Assam (India); Sarma, J. [Department of Mathematics, R. G. Baruah College, Guwahati-781025, Assam (India); Talukdar, M. [Computer Science Division, Institute of Advanced Study in Science Technology, Khanapara, Guwahati-781022, Assam (India)
1998-01-01
Employing quasipotential analysis, the Sagdeev potential equation has been derived in a multicomponent plasma consisting of free and trapped electrons and contaminated by the dust charged grains forming therein by the attachment of electrons to finite-size dust particles. Because of the free and trapped electrons in the dusty plasma, the plasma-acoustic wave exhibits the different features of various solitary waves. The Sagdeev potential equation, at a small-amplitude approximation, leads to the evaluation, by a proposed new formalism of a simple wave solution technique, of the new scenario of solitary wave propagation in a dusty plasma. It has been shown that the ordering of the nonisothermality in the dusty plasma also plays a unique role. In the case of a plasma with first-order nonisothermality, the Sagdeev potential equation derives the compressive solitary wave propagation, while for plasma with higher-order nonisothermality the method might fail to solve the Sagdeev potential equation and, thus, an alternate method is used to reveal the coexistence of compressive and rarefactive solitary waves. In addition, for certain plasma parameters, the solitary waves disappear and a double layer is expected. Again, with the better approximation in the Sagdeev potential, more features of solitary waves, known as spiky and explosive, along with the double layers, are also highlighted. The observations made of the solitary waves could be of further interest in the understanding of laboratory and space plasmas.{copyright} {ital 1998 American Institute of Physics.}
Flow and sediment transport induced by a plunging solitary wave
DEFF Research Database (Denmark)
Sumer, B. Mutlu; Sen, M.Berke; Karagali, Ioanna
2011-01-01
affected, by as much as a factor of 2, in the runup and hydraulic jump stages. The pore-water pressure measurements showed that the sediment at (or near) the surface of the bed experiences upward-directed pressure gradient forces during the downrush phase. The magnitude of this force can reach values......Two parallel experiments involving the evolution and runup of plunging solitary waves on a sloping bed were conducted: (1) a rigid-bed experiment, allowing direct (hot film) measurements of bed shear stresses, and (2) a sediment-bed experiment, allowing for the measurement of pore-water pressures...... is explained qualitatively in terms of the measured bed shear stress and the pressure gradient forces....
Scattering of quantized solitary waves in the cubic Schrodinger equation
International Nuclear Information System (INIS)
Dolan, L.
1976-01-01
The quantum mechanics for N particles interacting via a delta-function potential in one space dimension and one time dimension is known. The second-quantized description of this system has for its Euler-Lagrange equations of motion the cubic Schrodinger equation. This nonlinear differential equation supports solitary wave solutions. A quantization of these solitons reproduces the weak-coupling limit to the known quantum mechanics. The phase shift for two-body scattering and the energy of the N-body bound state is derived in this approximation. The nonlinear Schrodinger equation is contrasted with the sine-Gordon theory in respect to the ideas which the classical solutions play in the description of the quantum states
Solitary wave and periodic wave solutions for Burgers, Fisher ...
Indian Academy of Sciences (India)
the travelling wave solutions plays an important role in nonlinear sciences. Many power- ful methods have been presented, including the inverse scattering transform [1], Hirota's bilinear method [2], homotopy analysis method [3–5], variational iteration method [6,7], homotopy perturbation method [8–10], Painlevé expansion ...
Formation and dynamics of electrostatic solitary waves associated with relativistic electron beam
Moslem, W. M.; Bencheriet, F.; Sabry, R.; Djebli, M.
2012-04-01
Properties of nonlinear electrostatic solitary waves in a plasma are analyzed by using the hydrodynamic model for electrons, positrons, and relativistic electron beam. For this purpose, the Kadomtsev-Petviashvili (KP) equation has been derived and its analytical solution is presented. It is found that the nonlinear solitary structures can propagate as slow and fast modes. The dependence of these modes on the plasma parameters is defined numerically. Furthermore, positive and negative electrostatic solitary structures can exist. In order to show that the characteristics of the solitary wave profile are influenced by the plasma parameters, the relevant numerical analysis of the KP equation is obtained. The electrostatic solitary waves, as predicted here, may be associated with the nonlinear structures caused by the interaction of relativistic jets with plasma medium, such as in the active galactic nuclei and in the magnetosphere of collapsing stars.
Solitary impulse wave run-up and overland flow
International Nuclear Information System (INIS)
Fuchs, H.
2013-04-01
Impulse waves are generated by landslides, rockfalls or avalanches impacting a reservoir or natural lake. These long waves generated by the impulse transferred to the water body in combination with the usually short propagation distance within a lake lead to a large damage potential due to wave run-up or dam overtopping. Damages are then caused by (1) direct wave load on structures, (2) driftwood and float impact and (3) their deposits after water retreat. Major historic events occurred at Lituya Bay, Alaska, in 1958, or at the Vaiont Reservoir, Italy, in 1963. Recent events were observed at Lake Chehalis, Canada, or Lake Lucerne, Switzerland, both in 2007, or at the Lower Grindelwald proglacial lake, Switzerland, in 2009. Whereas previous VAW research aimed at the generation phase of landslide-generated impulse waves with a special focus on the wave characteristics, the current research concentrates on the opposite wave-shore interaction. A particular focus is given to the transition point from the shore slope to the horizontal plane where the orbital wave motion is transformed into a shore-parallel flow. As most literature relates only to plain wave run-up on a linearly-inclined plane and the few studies focussing on wave-induced overland flow are case studies considering only a specific bathymetry, currently no general conclusions on wave-induced overland flow can be drawn. The present study therefore intends to fill in this gap by physical modeling. Testing involved a new test-setup including a piston-type wave maker to generate solitary waves, and a smooth impermeable PVC shore of height w = 0.25 m with a connected horizontal overland flow portion. By varying the shore slope tanβ = 1/1.5, 1/2.5 and 1/5.0, the still water depth h = 0.16 - 0.24 m, and the relative wave height H/h = 0.1 -0.7, a wide range of basic parameters was covered. Overland flow depths and front velocities were measured along the shore using Ultrasonic Distance Sensors. Further, flow
Energy Technology Data Exchange (ETDEWEB)
Arevalo, Edward, E-mail: arevalo@temf.tu-darmstadt.d [Technische Universitaet Darmstadt, Institut fuer Theorie elektromagnetischer Felder, TEMF, Schlossgartenstr. 8, D-64289 Darmstadt (Germany)
2009-09-21
The effect of instability on the propagation of solitary waves along one-dimensional discrete nonlinear Schroedinger equation with cubic nonlinearity is revisited. A self-contained quasicontinuum approximation is developed to derive closed-form expressions for small-amplitude solitary waves. The notion that the existence of nonlinear solitary waves in discrete systems is a signature of the modulation instability is used. With the help of this notion we conjecture that instability effects on moving solitons can be qualitative estimated from the analytical solutions. Results from numerical simulations are presented to support this conjecture.
Existence domain of electrostatic solitary waves in the lunar wake
Rubia, R.; Singh, S. V.; Lakhina, G. S.
2018-03-01
Electrostatic solitary waves (ESWs) and double layers are explored in a four-component plasma consisting of hot protons, hot heavier ions (He++), electron beam, and suprathermal electrons having κ-distribution using the Sagdeev pseudopotential method. Three modes exist: slow and fast ion-acoustic modes and electron-acoustic mode. The occurrence of ESWs and their existence domain as a function of various plasma parameters, such as the number densities of ions and electron beam, the spectral index, κ, the electron beam velocity, the temperatures of ions, and electron beam, are analyzed. It is observed that both the slow and fast ion-acoustic modes support both positive and negative potential solitons as well as their coexistence. Further, they support a "forbidden gap," the region in which the soliton ceases to propagate. In addition, slow ion-acoustic solitons support the existence of both positive and negative potential double layers. The electron-acoustic mode is only found to support negative potential solitons for parameters relevant to the lunar wake plasma. Fast Fourier transform of a soliton electric field produces a broadband frequency spectrum. It is suggested that all three soliton types taken together can provide a good explanation for the observed electrostatic waves in the lunar wake.
Landau damping of dust acoustic solitary waves in nonthermal plasmas
Ghai, Yashika; Saini, N. S.; Eliasson, B.
2018-01-01
Dust acoustic (DA) solitary and shock structures have been investigated under the influence of Landau damping in a dusty plasma containing two temperature nonthermal ions. Motivated by the observations of Geotail spacecraft that reported two-temperature ion population in the Earth's magnetosphere, we have investigated the effect of resonant wave-particle interactions on DA nonlinear structures. The Korteweg-de Vries (KdV) equation with an additional Landau damping term is derived and its analytical solution is presented. The solution has the form of a soliton whose amplitude decreases with time. Further, we have illustrated the influence of Landau damping and nonthermality of the ions on DA shock structures by a numerical solution of the Landau damping modified KdV equation. The study of the time evolution of shock waves suggests that an initial shock-like pulse forms an oscillatory shock at later times due to the balance of nonlinearity, dispersion, and dissipation due to Landau damping. The findings of the present investigation may be useful in understanding the properties of nonlinear structures in the presence of Landau damping in dusty plasmas containing two temperature ions obeying nonthermal distribution such as in the Earth's magnetotail.
Nonlinear Wave Propagation and Solitary Wave Formation in Two-Dimensional Heterogeneous Media
Luna, Manuel
2011-05-01
Solitary wave formation is a well studied nonlinear phenomenon arising in propagation of dispersive nonlinear waves under suitable conditions. In non-homogeneous materials, dispersion may happen due to effective reflections between the material interfaces. This dispersion has been used along with nonlinearities to find solitary wave formation using the one-dimensional p-system. These solitary waves are called stegotons. The main goal in this work is to find two-dimensional stegoton formation. To do so we consider the nonlinear two-dimensional p-system with variable coefficients and solve it using finite volume methods. The second goal is to obtain effective equations that describe the macroscopic behavior of the variable coefficient system by a constant coefficient one. This is done through a homogenization process based on multiple-scale asymptotic expansions. We compare the solution of the effective equations with the finite volume results and find a good agreement. Finally, we study some stability properties of the homogenized equations and find they and one-dimensional versions of them are unstable in general.
Nonlinear wave modulation of cylindrical and spherical quantum ion-acoustic solitary waves
Sabry, R.; El-Labany, S. K.; Shukla, P. K.
2008-12-01
Cylindrical and spherical amplitude modulation of quantum ion-acoustic (QIA) envelope solitary waves in a dense quantum plasma comprised of electrons and ions is investigated. For this purpose, a one-dimensional quantum hydrodynamic model and the Poisson equation are considered. By using the standard reductive perturbation technique, a modified nonlinear Schrödinger equation with the geometrical and the quantum effects is derived. The effect of quantum corrections and the effect due to the cylindrical and spherical geometries on the propagation of the QIA envelope solitary waves are examined. It is shown that there exists a modulation instability period depending on the quantum parameter, which does not exist for the one-dimensional classical case.
International Nuclear Information System (INIS)
Sabry, R.
2009-01-01
A finite amplitude theory for ion-acoustic solitary waves and double layers in multicomponent plasma consisting of hot positrons, cold ions, and electrons with two-electron temperature distributions is presented. Conditions are obtained under which large amplitude stationary ion-acoustic solitary waves and double layers can exist. For the physical parameters of interest, the ion-acoustic solitary wave (double layers) profiles and the relationship between the maximum soliton (double layers) amplitude and the Mach number are found. Also, we have presented the region of existence of the large amplitude ion-acoustic waves by analyzing the structure of the pseudopotential. For the selected range of parameters, it is found that only positive solitary waves and double layers can exist. An analysis for the small amplitude limit through the Sagdeev pseudopotential analysis and the reductive perturbation theory shows the existence of positive and negative ion-acoustic solitary waves and double layers. The effects of positron concentration and temperature ratio on the characteristics of the solitary ion-acoustic waves and double layers (namely, the amplitude and width) are discussed in detail. The relevance of this investigation to space and laboratory plasmas is pointed out.
Sabry, R.
2009-07-01
A finite amplitude theory for ion-acoustic solitary waves and double layers in multicomponent plasma consisting of hot positrons, cold ions, and electrons with two-electron temperature distributions is presented. Conditions are obtained under which large amplitude stationary ion-acoustic solitary waves and double layers can exist. For the physical parameters of interest, the ion-acoustic solitary wave (double layers) profiles and the relationship between the maximum soliton (double layers) amplitude and the Mach number are found. Also, we have presented the region of existence of the large amplitude ion-acoustic waves by analyzing the structure of the pseudopotential. For the selected range of parameters, it is found that only positive solitary waves and double layers can exist. An analysis for the small amplitude limit through the Sagdeev pseudopotential analysis and the reductive perturbation theory shows the existence of positive and negative ion-acoustic solitary waves and double layers. The effects of positron concentration and temperature ratio on the characteristics of the solitary ion-acoustic waves and double layers (namely, the amplitude and width) are discussed in detail. The relevance of this investigation to space and laboratory plasmas is pointed out.
Dynamics of Solitary Wave Pulses Near the Zero-Dispersion Wavelength in Optical Fibers
National Research Council Canada - National Science Library
Akylas, Triantaphyllos
1998-01-01
.... Near the zero-dispersion wavelength (ZDW), the borderline between normal and anomalous dispersion, however, dispersive effects are relatively weak and it would seem most efficient to operate there, assuming that one can launch solitary wave...
Space-charge solitary waves and double layers in n-type compensated semiconductor quantum plasma
Banerjee, S.; Ghosh, B.
2018-03-01
Using quantum hydrodynamic (QHD) model and standard reductive perturbation method, we have investigated the formation and characteristics of space-charge solitary waves and double layers in n-type compensated drifting semiconductor plasma with varying doping profiles. Through numerical analysis, it is shown that the structures of space-charge solitary waves and double layers depend significantly on electron drift and compensation parameter which measures a comparative proportion of the donor, acceptor and intrinsic ion concentrations.
Directory of Open Access Journals (Sweden)
S. S. Ghosh
2004-01-01
Full Text Available The presence of dynamic, large amplitude solitary waves in the auroral regions of space is well known. Since their velocities are of the order of the ion acoustic speed, they may well be considered as being generated from the nonlinear evolution of ion acoustic waves. However, they do not show the expected width-amplitude correlation for K-dV solitons. Recent POLAR observations have actually revealed that the low altitude rarefactive ion acoustic solitary waves are associated with an increase in the width with increasing amplitude. This indicates that a weakly nonlinear theory is not appropriate to describe the solitary structures in the auroral regions. In the present work, a fully nonlinear analysis based on Sagdeev pseudopotential technique has been adopted for both parallel and oblique propagation of rarefactive solitary waves in a two electron temperature multi-ion plasma. The large amplitude solutions have consistently shown an increase in the width with increasing amplitude. The width-amplitude variation profile of obliquely propagating rarefactive solitary waves in a magnetized plasma have been compared with the recent POLAR observations. The width-amplitude variation pattern is found to fit well with the analytical results. It indicates that a fully nonlinear theory of ion acoustic solitary waves may well explain the observed anomalous width variations of large amplitude structures in the auroral region.
New family of solitary waves in granular dimer chains with no precompression.
Jayaprakash, K R; Starosvetsky, Yuli; Vakakis, Alexander F
2011-03-01
In the present paper we report the existence of a new family of solitary waves in general one-dimensional dimer chains with elastic interactions between beads obeying a strongly nonlinear Hertzian force law. These dimers consist of pairs of "heavy" and "light" beads with no precompression. The solitary waves reported herein can be considered as analogous to the solitary waves in general homogeneous granular chains studied by Nesterenko, in the sense that they do not involve separations between beads, but rather satisfy special symmetries or, equivalently antiresonances in their intrinsic dynamics. We conjecture that these solitary waves are the direct products of a countable infinity of antiresonances in the dimer. An interesting finding is that the solitary waves in the dimer propagate faster than solitary waves in the corresponding homogeneous granular chain obtained in the limit of no mass mismatch between beads (i.e., composed of only heavy beads). This finding, which might seem counterintuitive, indicates that under certain conditions nonlinear antiresonances can increase the speed of disturbance transmission in periodic granular media, through the generation of different ways for transferring energy to the far field of these media. From a practical point of view, this result can have interesting implications in applications where granular media are employed as shock transmitters or attenuators.
Integrability: mathematical methods for studying solitary waves theory
Wazwaz, Abdul-Majid
2014-03-01
In recent decades, substantial experimental research efforts have been devoted to linear and nonlinear physical phenomena. In particular, studies of integrable nonlinear equations in solitary waves theory have attracted intensive interest from mathematicians, with the principal goal of fostering the development of new methods, and physicists, who are seeking solutions that represent physical phenomena and to form a bridge between mathematical results and scientific structures. The aim for both groups is to build up our current understanding and facilitate future developments, develop more creative results and create new trends in the rapidly developing field of solitary waves. The notion of the integrability of certain partial differential equations occupies an important role in current and future trends, but a unified rigorous definition of the integrability of differential equations still does not exist. For example, an integrable model in the Painlevé sense may not be integrable in the Lax sense. The Painlevé sense indicates that the solution can be represented as a Laurent series in powers of some function that vanishes on an arbitrary surface with the possibility of truncating the Laurent series at finite powers of this function. The concept of Lax pairs introduces another meaning of the notion of integrability. The Lax pair formulates the integrability of nonlinear equation as the compatibility condition of two linear equations. However, it was shown by many researchers that the necessary integrability conditions are the existence of an infinite series of generalized symmetries or conservation laws for the given equation. The existence of multiple soliton solutions often indicates the integrability of the equation but other tests, such as the Painlevé test or the Lax pair, are necessary to confirm the integrability for any equation. In the context of completely integrable equations, studies are flourishing because these equations are able to describe the
Rational solitary wave and rogue wave solutions in coupled defocusing Hirota equation
Energy Technology Data Exchange (ETDEWEB)
Huang, Xin, E-mail: 14491558@qq.com
2016-06-03
Highlights: • The M/W shape rational solitary wave solutions and rogue wave solutions of coupled Hirota equations are given. • The baseband modulational stability theory is established in the defocusing coupled Hirota model. • The M/W shape rational solitary wave can be explained by the baseband modulational stability theory. - Abstract: We derive and study a general rational solution of a coupled defocusing Hirota equation which can be used to describe evolution of light in a two-mode fiber with defocusing Kerr effect and some certain high-order effects. We find some new excitation patterns in the model, such as M-shaped soliton, W-shaped soliton, anti-eye-shaped rogue wave and four-petaled flower rogue wave. The results are compared with the solutions obtained in other coupled systems like vector nonlinear Schrödinger equation, coupled focusing Hirota and Sasa–Satsuma equations. We explain the new characters by modulational instability properties. This further indicates that rational solution does not necessarily correspond to rogue wave excitation dynamics and the quantitative relation between nonlinear excitations and modulational instability should exist.
Viscous damping of solitary waves in the mud banks of Kerala, West coast of India
Digital Repository Service at National Institute of Oceanography (India)
Shenoi, S.S.C.; Murty, C.S.
Analysis of wave damping in mud bank region following the process of transfer of wave energy to the interior of fluid column through the boundary layer and the energy loss computations owing to viscous shear beneath the solitary wave over a smooth...
Head-on collision of large amplitude internal solitary waves of the first mode
Terletska, Kateryna; Maderich, Vladimir; Brovchenko, Igor; Jung, Kyung Tae; Talipova, Tatiana
2016-04-01
The dynamics and energetics of a frontal collision of internal solitary waves of depression and elevation of moderate and large amplitudes propagating in a two-layer stratified fluid are studied numerically in frame of the Navier-Stokes equations. It was considered symmetric and asymmetric head-on collisions. We propose the dimensionless characteristic of the wave collision ξ that is the ratio of the wave steepnesses. Wave runup normalized on the amplitude of incoming wave as function of the waves steepness is proposed. Interval 01 corresponds to the larger wave in the case of asymmetric collision. Results of modeling were compared with the results of laboratory experiments [1]. It was shown that the frontal collision of internal solitary waves of moderate amplitude leads to a small phase shift and to the generation of dispersive wavetrain trailing behind transmitted solitary wave. The phase shift grows with increasing amplitudes of the interacting waves and approaches the limiting value when amplitudes of the waves are equal to the upper/lower layer for waves of depression/elevation. The deviation of the maximum wave height during collision from the twice the amplitude are maximal when wave amplitudes are equal to the upper/lower layer for waves of depression/elevation, then it decays with growth of amplitudes of interacting waves. It was found that the interaction of waves of large amplitude leads to the shear instability and the formation of Kelvin - Helmholtz vortices in the interface layer, however, subsequently waves again become stable. References [1] R.-C. Hsu, M. H. Cheng, C.-Y. Chen, Potential hazards and dynamical analysis of interfacial solitary wave interactions. Nat Hazards. 65 (2013) 255-278
Solitary Wave Solutions to a Class of Modified Green-Naghdi Systems
Duchêne, Vincent; Nilsson, Dag; Wahlén, Erik
2017-12-01
We provide the existence and asymptotic description of solitary wave solutions to a class of modified Green-Naghdi systems, modeling the propagation of long surface or internal waves. This class was recently proposed by Duchêne et al. (Stud Appl Math 137:356-415, 2016) in order to improve the frequency dispersion of the original Green-Naghdi system while maintaining the same precision. The solitary waves are constructed from the solutions of a constrained minimization problem. The main difficulties stem from the fact that the functional at stake involves low order non-local operators, intertwining multiplications and convolutions through Fourier multipliers.
International Nuclear Information System (INIS)
Sanchez-Arriaga, G.; Lefebvre, E.
2011-01-01
The dynamics of two-dimensional s-polarized solitary waves is investigated with the aid of particle-in-cell (PIC) simulations. Instead of the usual excitation of the waves with a laser pulse, the PIC code was directly initialized with the numerical solutions from the fluid plasma model. This technique allows the analysis of different scenarios including the theoretical problems of the solitary wave stability and their collision as well as features already measured during laser-plasma experiments such as the emission of electromagnetic bursts when the waves reach the plasma-vacuum interface, or their expansion on the ion time scale, usually named post-soliton evolution. Waves with a single density depression are stable whereas multihump solutions decay to several waves. Contrary to solitons, two waves always interact through a force that depends on their relative phases, their amplitudes, and the distance between them. On the other hand, the radiation pattern at the plasma-vacuum interface was characterized, and the evolution of the diameter of different waves was computed and compared with the ''snow plow'' model.
Travelling Solitary Wave Solutions for Generalized Time-delayed Burgers-Fisher Equation
International Nuclear Information System (INIS)
Deng Xijun; Han Libo; Li Xi
2009-01-01
In this paper, travelling wave solutions for the generalized time-delayed Burgers-Fisher equation are studied. By using the first-integral method, which is based on the ring theory of commutative algebra, we obtain a class of travelling solitary wave solutions for the generalized time-delayed Burgers-Fisher equation. A minor error in the previous article is clarified. (general)
Collaborative Research: Dynamics of Electrostatic Solitary Waves on Current Layers
Energy Technology Data Exchange (ETDEWEB)
Pickett, Jolene S.
2012-10-31
The research carried out under the subject grant has provided insight into the generation of Electrostatic Solitary Waves (ESWs), which are nonlinear structures observed in space plasma data. These ESWs, appearing as pulses in the electric field time series data, represent the presence of several hundred meters to kilometer size positive potential structures, similar to champagne bubbles, where the electrons have been depleted, and which travel along Earth's magnetic field lines. The laboratory experiments carried out at the UCLA LAPD under the grant allowed us the opportunity to change various plasma and field conditions within the plasma device, and experiment with injection of suprathermal electron beams, in order to create ESWs. This then allowed us to determine the most likely method of generation of the ESWs. By comparing the properties of the ESWs observed in the LAPD to those observed in space and the plasma and field conditions under which those ESWs were observed in both locations, we were able to evaluate various ESW generation mechanisms. The findings of the laboratory experiments are that ESWs are generated through a lower hybrid instability. The ESWs observed in Earth's auroral current regions have similar characteristics to those generated by the laboratory when referenced to basic plasma and field characteristics, leading us to the conclusion that the lower hybrid drift instability is certainly a possibility for generation of the ESWs, at least in the auroral (northern/southern lights) regions. Due to space instrumentation insufficiencies and the limitations on telemetry, and thus poor time resolution, it is not possible to determine absolutely what generates these bubbles in space, but the laboratory experiments and supporting simulations have helped us to further our understanding of the processes under which they are generated. The public benefits from the findings of this research because the research is focused on current layers
Dynamical barrier for the formation of solitary waves in discrete lattices
International Nuclear Information System (INIS)
Kevrekidis, P.G.; Espinola-Rocha, J.A.; Drossinos, Y.; Stefanov, A.
2008-01-01
We consider the problem of the existence of a dynamical barrier of 'mass' that needs to be excited on a lattice site to lead to the formation and subsequent persistence of localized modes for a nonlinear Schroedinger lattice. We contrast the existence of a dynamical barrier with its absence in the static theory of localized modes in one spatial dimension. We suggest an energetic criterion that provides a sufficient, but not necessary, condition on the amplitude of a single-site initial condition required to form a solitary wave. We show that this effect is not one-dimensional by considering its two-dimensional analog. The existence of a sufficient condition for the excitation of localized modes in the non-integrable, discrete, nonlinear Schroedinger equation is compared to the dynamics of excitations in the integrable, both discrete and continuum, version of the nonlinear Schroedinger equation
Dynamical barrier for the formation of solitary waves in discrete lattices
Energy Technology Data Exchange (ETDEWEB)
Kevrekidis, P.G. [Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA 01003 (United States)], E-mail: kevrekid@math.umass.edu; Espinola-Rocha, J.A. [Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA 01003 (United States); Drossinos, Y. [European Commission, Joint Research Centre, I-21020 Ispra (Vatican City State, Holy See,) (Italy); School of Mechanical and Systems Engineering, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU (United Kingdom); Stefanov, A. [Department of Mathematics, University of Kansas, 1460 Jayhawk Blvd., Lawrence, KS 66045-7523 (United States)
2008-03-24
We consider the problem of the existence of a dynamical barrier of 'mass' that needs to be excited on a lattice site to lead to the formation and subsequent persistence of localized modes for a nonlinear Schroedinger lattice. We contrast the existence of a dynamical barrier with its absence in the static theory of localized modes in one spatial dimension. We suggest an energetic criterion that provides a sufficient, but not necessary, condition on the amplitude of a single-site initial condition required to form a solitary wave. We show that this effect is not one-dimensional by considering its two-dimensional analog. The existence of a sufficient condition for the excitation of localized modes in the non-integrable, discrete, nonlinear Schroedinger equation is compared to the dynamics of excitations in the integrable, both discrete and continuum, version of the nonlinear Schroedinger equation.
Directory of Open Access Journals (Sweden)
O. D. Shishkina
2013-10-01
Full Text Available An interaction of internal solitary waves with the shelf edge in the time periods related to the presence of a pronounced seasonal pycnocline in the Red Sea and in the Alboran Sea is analysed via satellite photos and SAR images. Laboratory data on transformation of a solitary wave of depression while passing along the transverse bottom step were obtained in a tank with a two-layer stratified fluid. The certain difference between two characteristic types of hydrophysical phenomena was revealed both in the field observations and in experiments. The hydrological conditions for these two processes were named the "deep" and the "shallow" shelf respectively. The first one provides the generation of the secondary periodic short internal waves – "runaway" edge waves – due to change in the polarity of a part of a soliton approaching the shelf normally. Another one causes a periodic shear flow in the upper quasi-homogeneous water layer with the period of incident solitary wave. The strength of the revealed mechanisms depends on the thickness of the water layer between the pycnocline and the shelf bottom as well as on the amplitude of the incident solitary wave.
Arbitrary amplitude dust kinetic Alfvén solitary waves in the presence of polarization force
Singh, Manpreet; Kaur, Nimardeep; Saini, N. S.
2018-02-01
In this investigation, the effect of polarization force on dust kinetic Alfvén solitary waves (DKASWs) in a magnetized dusty plasma consisting of dust fluid, electrons, and positively charged ions is studied. By incorporating density non-uniformity and polarization force in the fluid model equations, the energy balance equation is derived, and from the expression for Sagdeev pseudopotential, the existence conditions for solitary structures in terms of Mach number are determined. From the numerical analysis of Sagdeev pseudopotential, compressive and rarefactive DKASWs at sub- and super-Alfvénic speeds are observed. These waves are significantly affected by varying polarization force, angle of propagation, plasma beta, and Mach number.
Solitary waves on inclined films: their characteristics and the effects on wall shear stress
Energy Technology Data Exchange (ETDEWEB)
Tihon, J. [Academy of Sciences of the Czech Republic, Institute of Chemical Process Fundamentals, Prague 6 (Czech Republic); Serifi, K.; Argyriadi, K.; Bontozoglou, V. [University of Thessaly, Department of Mechanical and Industrial Engineering, Volos (Greece)
2006-07-15
The properties of solitary waves, developing from inlet disturbances of controlled frequency along an inclined film flow, are systematically studied experimentally and computationally. Time-variations of film height and wall shear stress are measured, using respectively a capacitance probe and an electrodiffusion sensor. Computational data are provided from simulations performed by a Galerkin finite element scheme. The height and spacing of solitary humps, their phase velocity and the wavelength of the preceding capillary ripples are reported as functions of the Reynolds number (10
Advection of pollutants by internal solitary waves in oceanic and atmospheric stable stratifications
Directory of Open Access Journals (Sweden)
G. W. Haarlemmer
1998-01-01
Full Text Available When a pollutant is released into the ocean or atmosphere under turbulent conditions, even a steady release is captured by large eddies resulting in localized patches of high concentration of the pollutant. If such a cloud of pollutant subsequently enters a stable stratification-either a pycnocline or thermocline-then internal waves are excited. Since large solitary internal waves have a recirculating core, pollutants may be trapped in the sclitary wave, and advected large distances through the waveguide provided by the stratification. This paper addresses the mechanisms, through computer and physical simulation, by which a localized release of a dense pollutant results in solitary waves that trap the pollutant or disperse the pollutant faster than in the absence of the waves.
El-Labany, S. K.; Sabry, R.; El-Shamy, E. F.; Khedr, D. M.; Khedr
2013-10-01
Investigation of arbitrary amplitude nonlinear ion-acoustic solitary waves which accompany collisionless positive-negative ion plasmas with high-energy electrons (represented by kappa distribution) is presented. Arbitrary amplitude solitary waves are investigated by deriving an energy-integral equation involving a Sagdeev-like pseudopotential. The existence regions of solitary pulses are, defined precisely, modified by the superthermality of energetic electrons. Furthermore, numerical calculations reveal that both compressive and rarefactive pulses may exist for negative ion mass groups in Titan's atmosphere. The superthermality of energetic electrons are found to modify the existence domains of large amplitude ion-acoustic waves in Titan's atmosphere. The dependence of solitary excitation characteristics on the superthermal parameter, the negative ion concentration, the positive-to-negative ions mass ratio, and the Mach number have been investigated. The present study might be helpful to understand the excitation of fully nonlinear ion-acoustic solitary pulses that may appear in the interplanetary medium and/or in the astrophysical plasmas in general.
Nonlinear propagation of dust-acoustic solitary waves in a dusty ...
Indian Academy of Sciences (India)
... Lecture Workshops · Refresher Courses · Symposia · Live Streaming. Home; Journals; Pramana – Journal of Physics; Volume 80; Issue 6. Nonlinear propagation of dust-acoustic solitary waves in a dusty plasma with arbitrarily charged dust and trapped electrons. O Rahman A A Mamun. Volume 80 Issue 6 June 2013 pp ...
Czech Academy of Sciences Publication Activity Database
Pickett, J. S.; Chen, L. J.; Mutel, R. L.; Christopher, I. W.; Santolík, Ondřej; Lakhina, G. S.; Singh, S. V.; Reddy, R. V.; Gurnett, D. A.; Tsurutani, B. T.; Lucek, E.; Lavraud, B.
2008-01-01
Roč. 41, č. 10 (2008), s. 1666-1676 ISSN 0273-1177 Institutional research plan: CEZ:AV0Z30420517 Keywords : Electrostatic solitary waves * ESW propagation * Cluster * Magnetosheath * Auroral acceleration region * Cluster wideband data Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.860, year: 2008
Electrostatic solitary waves observed at Saturn by Cassini inside 10 Rs and near Enceladus
Czech Academy of Sciences Publication Activity Database
Pickett, J. S.; Kurth, W. S.; Gurnett, D. A.; Huff, R. L.; Faden, J. B.; Averkamp, T. F.; Píša, David; Jones, G. H.
2015-01-01
Roč. 120, č. 8 (2015), s. 6569-6580 ISSN 2169-9380 Institutional support: RVO:68378289 Keywords : electrostatic solitary waves * Saturn * Enceladus * plasma instabilities Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.318, year: 2015 http://onlinelibrary.wiley.com/doi/10.1002/2015JA021305/full
Space-charge solitary waves and double layers in n-type ...
Indian Academy of Sciences (India)
S BANERJEE
2018-02-20
Feb 20, 2018 ... Abstract. Using quantum hydrodynamic (QHD) model and standard reductive perturbation method, we have investigated the formation and characteristics of space-charge solitary waves and double layers in n-type compen- sated drifting semiconductor plasma with varying doping profiles. Through ...
Ali, Rustam; Saha, Asit; Chatterjee, Prasanta
2017-12-01
Analytical electron acoustic solitary wave (EASW) solution is investigated in the presence of periodic force for an unmagnetized plasma consisting of cold electron fluid, superthermal hot electrons, and stationary ions. Employing the reductive perturbation technique, the forced Korteg-de Vries (KdV) equation is derived for electron acoustic waves. For the first time, an analytical solution for EASWs is derived in the presence of periodic force. The effects of the ratio between hot electron and cold electron number densities at equilibrium (α), spectral index (κ), speed of the traveling wave (M), strength (f0), and frequency (ω) of the periodic force are studied on the analytical solution of EASWs. It is observed that the parameters α, κ, M, f0, and ω affect significantly the structures of the electron acoustic solitary waves. The results may have relevance in laboratory plasmas as well as in space plasma environments.
Energy Technology Data Exchange (ETDEWEB)
Singh, S. V., E-mail: satyavir@iigs.iigm.res.in; Lakhina, G. S., E-mail: lakhina@iigs.iigm.res.in [Indian Institute of Geomagnetism, New Panvel (W), Navi Mumbai (India); University of the Western Cape, Belville (South Africa); Devanandhan, S., E-mail: devanandhan@gmail.com [Indian Institute of Geomagnetism, New Panvel (W), Navi Mumbai (India); Bharuthram, R., E-mail: rbharuthram@uwc.ac.za [University of the Western Cape, Belville (South Africa)
2016-08-15
A theoretical investigation is carried out to study the obliquely propagating electron acoustic solitary waves having nonthermal hot electrons, cold and beam electrons, and ions in a magnetized plasma. We have employed reductive perturbation theory to derive the Korteweg-de-Vries-Zakharov-Kuznetsov (KdV-ZK) equation describing the nonlinear evolution of these waves. The two-dimensional plane wave solution of KdV-ZK equation is analyzed to study the effects of nonthermal and beam electrons on the characteristics of the solitons. Theoretical results predict negative potential solitary structures. We emphasize that the inclusion of finite temperature effects reduces the soliton amplitudes and the width of the solitons increases by an increase in the obliquity of the wave propagation. The numerical analysis is presented for the parameters corresponding to the observations of “burst a” event by Viking satellite on the auroral field lines.
New theory of the Great Red Spot from solitary waves in the Jovian atmosphere
International Nuclear Information System (INIS)
Maxworthy, T.; Redekopp, L.G.
1976-01-01
It is stated that the nature of the Great Red Spot on Jupiter is a persistent problem. It is considered here that 'solitary' waves on a horizontally sheared zonal flow in a rotating stratified atmosphere would explain many of the known GRS characteristics and also other features that have been observed on Jupiter. 'Solitary' waves are isolated permanent waves in which non-linear steepening balances dispersive spreading effects, and they can arise from arbitrary distrurbances and interact non-linearly without changing their shape. The only memory of such an interaction is a finite spatial phase shift between the fast- and the pre-interaction trajectories; the interaction looks like a rapid acceleration of one wave through another. The matter is here treated mathematically. A number of examples similar to Jupiter's GRS are mentioned in the discussion. (U.K.)
Forced solitary Rossby waves under the influence of slowly varying topography with time
International Nuclear Information System (INIS)
Yang Hong-Wei; Yin Bao-Shu; Yang De-Zhou; Xu Zhen-Hua
2011-01-01
By using a weakly nonlinear and perturbation method, the generalized inhomogeneous Korteweg—de Vries (KdV)—Burgers equation is derived, which governs the evolution of the amplitude of Rossby waves under the influence of dissipation and slowly varying topography with time. The analysis indicates that dissipation and slowly varying topography with time are important factors in causing variation in the mass and energy of solitary waves. (general)
Characteristics of solitary waves in a relativistic degenerate ion beam driven magneto plasma
Deka, Manoj Kr.; Dev, Apul N.; Misra, Amar P.; Adhikary, Nirab C.
2018-01-01
The nonlinear propagation of a small amplitude ion acoustic solitary wave in a relativistic degenerate magneto plasma in the presence of an ion beam is investigated in detail. The nonlinear equations describing the evolution of a solitary wave in the presence of relativistic non-degenerate magnetized positive ions and ion beams including magnetized degenerate relativistic electrons are derived in terms of Zakharov-Kuznetsov (Z-K) equation for such plasma systems. The ion beams which are a ubiquitous ingredient in such plasma systems are found to have a decisive role in the propagation of a solitary wave in such a highly dense plasma system. The conditions of a wave, propagating with typical solitonic characteristics, are examined and discussed in detail under suitable conditions of different physical parameters. Both a subsonic and supersonic wave can propagate in such plasmas bearing different characteristics under different physical situations. A detailed analysis of waves propagating in subsonic and/or supersonic regime is carried out. The ion beam concentrations, magnetic field, as well as ion beam streaming velocity are found to play a momentous role on the control of the amplitude and width of small amplitude perturbation in both weakly (or non-relativistic) and relativistic plasmas.
On the Dynamics of Two-Dimensional Capillary-Gravity Solitary Waves with a Linear Shear Current
Directory of Open Access Journals (Sweden)
Dali Guo
2014-01-01
Full Text Available The numerical study of the dynamics of two-dimensional capillary-gravity solitary waves on a linear shear current is presented in this paper. The numerical method is based on the time-dependent conformal mapping. The stability of different kinds of solitary waves is considered. Both depression wave and large amplitude elevation wave are found to be stable, while small amplitude elevation wave is unstable to the small perturbation, and it finally evolves to be a depression wave with tails, which is similar to the irrotational capillary-gravity waves.
PIC simulation of compressive and rarefactive dust ion-acoustic solitary waves
Energy Technology Data Exchange (ETDEWEB)
Li, Zhong-Zheng; Zhang, Heng; Hong, Xue-Ren; Gao, Dong-Ning; Zhang, Jie; Duan, Wen-Shan, E-mail: duanws@nwnu.edu.cn [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU & IMP CAS, Northwest Normal University, Lanzhou 730070 (China); Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Yang, Lei, E-mail: lyang@impcas.ac.cn [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU & IMP CAS, Northwest Normal University, Lanzhou 730070 (China); Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Department of Physics, Lanzhou University, Lanzhou 730000 (China)
2016-08-15
The nonlinear propagations of dust ion-acoustic solitary waves in a collisionless four-component unmagnetized dusty plasma system containing nonextensive electrons, inertial negative ions, Maxwellian positive ions, and negatively charged static dust grains have been investigated by the particle-in-cell method. By comparing the simulation results with those obtained from the traditional reductive perturbation method, it is observed that the rarefactive KdV solitons propagate stably at a low amplitude, and when the amplitude is increased, the prime wave form evolves and then gradually breaks into several small amplitude solitary waves near the tail of soliton structure. The compressive KdV solitons propagate unstably and oscillation arises near the tail of soliton structure. The finite amplitude rarefactive and compressive Gardner solitons seem to propagate stably.
International Nuclear Information System (INIS)
Huang Wenhua; Liu Yulu; Lu Zhiming
2007-01-01
A general solution including three arbitrary functions is obtained for the (2 + 1)-dimensional high-order Broer-Kaup equation by means of WTC truncation method. From the general solution, doubly periodic wave solutions in terms of the Jacobian elliptic functions with different modulus and folded solitary wave solutions determined by appropriate multiple valued functions are obtained. Some interesting novel features and interaction properties of these exact solutions and coherent localized structures are revealed
Algebraic method for constructing singular steady solitary waves: a case study
Clamond, Didier; Dutykh, Denys; Galligo, André
2016-07-01
This article describes the use of algebraic methods in a phase plane analysis of ordinary differential equations. The method is illustrated by the study of capillary-gravity steady surface waves propagating in shallow water. We consider the (fully nonlinear, weakly dispersive) Serre-Green-Naghdi equation with surface tension, because it provides a tractable model that, at the same time, is not too simple, so interest in the method can be emphasized. In particular, we analyse a special class of solutions, the solitary waves, which play an important role in many fields of physics. In capillary-gravity regime, there are two kinds of localized infinitely smooth travelling wave solutions-solitary waves of elevation and of depression. However, if we allow the solitary waves to have an angular point, then the `zoology' of solutions becomes much richer, and the main goal of this study is to provide a complete classification of such singular localized solutions using the methods of the effective algebraic geometry.
Zou, Li; Tian, Shou-Fu; Feng, Lian-Li
2017-12-01
In this paper, we consider the (2+1)-dimensional breaking soliton equation, which describes the interaction of a Riemann wave propagating along the y-axis with a long wave along the x-axis. By virtue of the truncated Painlevé expansion method, we obtain the nonlocal symmetry, Bäcklund transformation and Schwarzian form of the equation. Furthermore, by using the consistent Riccati expansion (CRE), we prove that the breaking soliton equation is solvable. Based on the consistent tan-function expansion, we explicitly derive the interaction solutions between solitary waves and cnoidal periodic waves.
Quantum ion-acoustic solitary waves in weak relativistic plasma
Indian Academy of Sciences (India)
ion-acoustic waves. Recently, Stenflo et al [24] observed two new low-frequency elec- trostatic modes in ultra-cold unmagnetized quantum dusty plasmas. Ali and Shukla ... waves in a nonuniform ultra-cold Fermi dusty gas composed of inertialess electrons, and ions as well ... the Van Allen radiation belts [34] etc. Streaming ...
Solitary Alfven wave envelopes and the modulational instability
International Nuclear Information System (INIS)
Kennel, C.F.
1987-06-01
The derivative nonlinear Schroedinger equation describes the modulational instability of circularly polarized dispersive Alfven wave envelopes. It also may be used to determine the properties of finite amplitude localized stationary wave envelopes. Such envelope solitons exist only in conditions of modulational stability. This leaves open the question of whether, and if so, how, the modulational instability produces envelope solitons. 12 refs
Dust acoustic solitary and shock waves in strongly coupled dusty ...
Indian Academy of Sciences (India)
mal vortex-like ion distribution and strongly correlated grains in a liquid-like state and discussed about the properties of shock ... shock waves in coupled dusty plasma with Boltzmann distribution of ions. Ghosh et al have studied the effect of ... ues of parameters where the nonlinear term is zero. Also new kind of shock wave.
Ship-induced solitary Riemann waves of depression in Venice Lagoon
International Nuclear Information System (INIS)
Parnell, Kevin E.; Soomere, Tarmo; Zaggia, Luca; Rodin, Artem; Lorenzetti, Giuliano; Rapaglia, John; Scarpa, Gian Marco
2015-01-01
We demonstrate that ships of moderate size, sailing at low depth Froude numbers (0.37–0.5) in a navigation channel surrounded by shallow banks, produce depressions with depths up to 2.5 m. These depressions (Bernoulli wakes) propagate as long-living strongly nonlinear solitary Riemann waves of depression substantial distances into Venice Lagoon. They gradually become strongly asymmetric with the rear of the depression becoming extremely steep, similar to a bore. As they are dynamically similar, air pressure fluctuations moving over variable-depth coastal areas could generate meteorological tsunamis with a leading depression wave followed by a devastating bore-like feature. - Highlights: • Unprecedently deep long-living ship-induced waves of depression detected. • Such waves are generated in channels with side banks under low Froude numbers. • The propagation of these waves is replicated using Riemann waves. • Long-living waves of depression form bore-like features at rear slope
Ship-induced solitary Riemann waves of depression in Venice Lagoon
Energy Technology Data Exchange (ETDEWEB)
Parnell, Kevin E. [College of Marine and Environmental Sciences and Centre for Tropical Environmental and Sustainability Sciences, James Cook University, Queensland 4811 (Australia); Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Soomere, Tarmo, E-mail: soomere@cs.ioc.ee [Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Estonian Academy of Sciences, Kohtu 6, 10130 Tallinn (Estonia); Zaggia, Luca [Institute of Marine Sciences, National Research Council, Castello 2737/F, 30122 Venice (Italy); Rodin, Artem [Institute of Cybernetics at Tallinn University of Technology, Akadeemia tee 21, 12618 Tallinn (Estonia); Lorenzetti, Giuliano [Institute of Marine Sciences, National Research Council, Castello 2737/F, 30122 Venice (Italy); Rapaglia, John [Sacred Heart University Department of Biology, 5151 Park Avenue, Fairfield, CT 06825 (United States); Scarpa, Gian Marco [Università Ca' Foscari, Dorsoduro 3246, 30123 Venice (Italy)
2015-03-06
We demonstrate that ships of moderate size, sailing at low depth Froude numbers (0.37–0.5) in a navigation channel surrounded by shallow banks, produce depressions with depths up to 2.5 m. These depressions (Bernoulli wakes) propagate as long-living strongly nonlinear solitary Riemann waves of depression substantial distances into Venice Lagoon. They gradually become strongly asymmetric with the rear of the depression becoming extremely steep, similar to a bore. As they are dynamically similar, air pressure fluctuations moving over variable-depth coastal areas could generate meteorological tsunamis with a leading depression wave followed by a devastating bore-like feature. - Highlights: • Unprecedently deep long-living ship-induced waves of depression detected. • Such waves are generated in channels with side banks under low Froude numbers. • The propagation of these waves is replicated using Riemann waves. • Long-living waves of depression form bore-like features at rear slope.
On the generation and evolution of internal solitary waves in the southern Red Sea
Guo, Daquan
2015-04-01
Satellite observations recently revealed the existence of trains of internal solitary waves in the southern Red Sea between 16.0°N and 16.5°N, propagating from the centre of the domain toward the continental shelf [Da silva et al., 2012]. Given the relatively weak tidal velocity in this area and their generation in the central of the domain, Da Silva suggested three possible mechanisms behind the generation of the waves, namely Resonance and disintegration of interfacial tides, Generation of interfacial tides by impinging, remotely generated internal tidal beams and for geometrically focused and amplified internal tidal beams. Tide analysis based on tide stations data and barotropic tide model in the Red Sea shows that tide is indeed very weak in the centre part of the Red Sea, but it is relatively strong in the northern and southern parts (reaching up to 66 cm/s). Together with extreme steep slopes along the deep trench, it provides favourable conditions for the generation of internal solitary in the southern Red Sea. To investigate the generation mechanisms and study the evolution of the internal waves in the off-shelf region of the southern Red Sea we have implemented a 2-D, high-resolution and non-hydrostatic configuration of the MIT general circulation model (MITgcm). Our simulations reproduce well that the generation process of the internal solitary waves. Analysis of the model\\'s output suggests that the interaction between the topography and tidal flow with the nonlinear effect is the main mechanism behind the generation of the internal solitary waves. Sensitivity experiments suggest that neither tidal beam nor the resonance effect of the topography is important factor in this process.
Ayub, Kamran; Khan, M. Yaqub; Mahmood-Ul-Hassan, Qazi; Ahmad, Jamshad
2017-09-01
Nonlinear mathematical problems and their solutions attain much attention in solitary waves. In soliton theory, an efficient tool to attain various types of soliton solutions is the \\exp (-φ (ζ ))-expansion technique. This article is devoted to find exact travelling wave solutions of Drinfeld-Sokolov equation via a reliable mathematical technique. By using the proposed technique, we attain soliton wave solution of various types. It is observed that the technique under discussion is user friendly with minimum computational work, and can be extended for physical problems of different nature in mathematical physics.
Tribeche, Mouloud; Sabry, Refaat
2012-10-01
Nonlinear dynamics of electron-acoustic solitary waves in a magnetized plasma whose constituents are cold magnetized electron fluid, hot electrons featuring Tsallis distribution, and stationary ions are examined. The nonlinear evolution equation (i.e., Zakharov-Kuznetsov (ZK) equation), governing the propagation of EAS waves in such plasma is derived and investigated analytically and numerically, for parameter regimes relevant to the dayside auroral zone. It is revealed that the amplitude, strength and nature of the nonlinear EAS waves are extremely sensitive to the degree of the hot electron nonextensivity. Furthermore, the obtained results are in good agreement with the observations made by the Viking satellite.
Measurement and modelling of bed shear induced by solitary waves
Digital Repository Service at National Institute of Oceanography (India)
JayaKumar, S.
horizontal continental shelf. Measurements of bed shear stress, surface elevation and flow velocities were carried out. Periodic waves were also generated and the bed shear stresses measured over a horizontal bed were found to be comparable with the earlier...
Energy Technology Data Exchange (ETDEWEB)
Ghosh, Uday Narayan, E-mail: unghosh1@rediffmail.com; Chatterjee, Prasanta; Roychoudhury, Rajkumar [Department of Mathematics, Siksha Bhavana, Visva Bharati, Santiniketan 731235 (India)
2015-07-15
Recently Gun Li et al. discussed “Effects of damping solitary wave in a viscosity bounded plasma” [Phys. Plasmas 21, 022118 (2014)]. The paper contains some serious errors which have been pointed out in this Comment.
Head-on collision of ion-acoustic solitary waves in multicomponent plasmas with positrons
El-Shamy, E. F.; Sabry, R.; Moslem, W. M.; Shukla, P. K.
2010-08-01
The head-on collision between two ion-acoustic solitary waves in an unmagnetized multicomponent plasma consisting of hot ions, hot positrons, and two-electron temperature distributions is investigated using the extended Poincaré-Lighthill-Kuo method. The Kortwege-de Vries equations and the analytical phase shifts after the head-on collision of two solitary waves in this multicomponent plasma are obtained. The effects of two different types of isothermal electrons, the ratio of the hot ion temperature to the effective temperature, the ratio of the effective temperature to the positron temperature, the ratio of the number density of positrons to that of electrons species, and the physical processes (either isothermal or adiabatic) on the phase shifts are studied. It is found that these parameters can significantly influence the phase shifts of the solitons. The relevance of this investigation to space and laboratory plasmas is pointed out.
Solitary waves under the competition of linear and nonlinear periodic potentials
International Nuclear Information System (INIS)
Rapti, Z; Kevrekidis, P G; Konotop, V V; Jones, C K R T
2007-01-01
In this paper, we study the competition of the linear and nonlinear lattices and its effects on the stability and dynamics of bright solitary waves. We consider both lattices in a perturbative framework, whereby the technique of Hamiltonian perturbation theory can be used to obtain information about the existence of solutions, and the same approach, as well as eigenvalue count considerations, can be used to obtain detailed conditions about their linear stability. We find that the analytical results are in very good agreement with our numerical findings and can also be used to predict features of the dynamical evolution of such solutions. A particularly interesting result of these considerations is the existence of a tunable cancellation effect between the linear and nonlinear lattices that allows for increased mobility of the solitary wave
Vector dark-antidark solitary waves in multicomponent Bose-Einstein condensates
Danaila, I.; Khamehchi, M. A.; Gokhroo, V.; Engels, P.; Kevrekidis, P. G.
2016-11-01
Multicomponent Bose-Einstein condensates exhibit an intriguing variety of nonlinear structures. In recent theoretical work [C. Qu, L. P. Pitaevskii, and S. Stringari, Phys. Rev. Lett. 116, 160402 (2016), 10.1103/PhysRevLett.116.160402], the notion of magnetic solitons has been introduced. Here we examine a variant of this concept in the form of vector dark-antidark solitary waves in multicomponent Bose-Einstein condensates (BECs). We first provide concrete experimental evidence for such states in an atomic BEC and subsequently illustrate the broader concept of these states, which are based on the interplay between miscibility and intercomponent repulsion. Armed with this more general conceptual framework, we expand the notion of such states to higher dimensions presenting the possibility of both vortex-antidark states and ring-antidark-ring (dark soliton) states. We perform numerical continuation studies, investigate the existence of these states, and examine their stability using the method of Bogoliubov-de Gennes analysis. Dark-antidark and vortex-antidark states are found to be stable for broad parametric regimes. In the case of ring dark solitons, where the single-component ring state is known to be unstable, the vector entity appears to bear a progressively more and more stabilizing role as the intercomponent coupling is increased.
Energy Technology Data Exchange (ETDEWEB)
Mayout, Saliha; Tribeche, Mouloud, E-mail: mouloudtribeche@yahoo.fr [Plasma Physics Group (PPG), Theoretical Physics Laboratory (TPL), Faculty of Sciences- Physics, University of Bab-Ezzouar, U.S.T.H.B, B.P. 32, El Alia, Algiers 16111 (Algeria); Sahu, Biswajit [Department of Mathematics, West Bengal State University, Barasat, Kolkata-700126 (India)
2015-12-15
A theoretical study on the nonlinear propagation of nonplanar (cylindrical and spherical) dust ion-acoustic solitary waves (DIASW) is carried out in a dusty plasma, whose constituents are inertial ions, superthermal electrons, and charge fluctuating stationary dust particles. Using the reductive perturbation theory, a modified Korteweg-de Vries equation is derived. It is shown that the propagation characteristics of the cylindrical and spherical DIA solitary waves significantly differ from those of their one-dimensional counterpart.
Solitary Waves on Inclined Films: Their Characteristics and the Effect on Wall Shear Stress
Czech Academy of Sciences Publication Activity Database
Tihon, Jaroslav; Serifi, K.; Argyriadi, K.; Bontozoglou, V.
2006-01-01
Roč. 41, č. 1 (2006), s. 79-89 ISSN 0723-4864 R&D Projects: GA AV ČR(CZ) IAA4072914 Grant - others:HPMT(XE) CT/2000/00074 Institutional research plan: CEZ:AV0Z40720504 Keywords : wavy film flow * solitary waves * wall shear stress Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.112, year: 2006
Combined solitary-wave solution for coupled higher-order nonlinear Schroedinger equations
International Nuclear Information System (INIS)
Tian Jinping; Tian Huiping; Li Zhonghao; Zhou Guosheng
2004-01-01
Coupled nonlinear Schroedinger equations model several interesting physical phenomena. We used a trigonometric function transform method based on a homogeneous balance to solve the coupled higher-order nonlinear Schroedinger equations. We obtained four pairs of exact solitary-wave solutions including a dark and a bright-soliton pair, a bright- and a dark-soliton pair, a bright- and a bright-soliton pair, and the last pair, a combined bright-dark-soliton pair
Diverging probability-density functions for flat-top solitary waves
Peleg, Avner; Chung, Yeojin; Dohnal, Tomáš; Nguyen, Quan M.
2009-08-01
We investigate the statistics of flat-top solitary wave parameters in the presence of weak multiplicative dissipative disorder. We consider first propagation of solitary waves of the cubic-quintic nonlinear Schrödinger equation (CQNLSE) in the presence of disorder in the cubic nonlinear gain. We show by a perturbative analytic calculation and by Monte Carlo simulations that the probability-density function (PDF) of the amplitude η exhibits loglognormal divergence near the maximum possible amplitude ηm , a behavior that is similar to the one observed earlier for disorder in the linear gain [A. Peleg , Phys. Rev. E 72, 027203 (2005)]. We relate the loglognormal divergence of the amplitude PDF to the superexponential approach of η to ηm in the corresponding deterministic model with linear/nonlinear gain. Furthermore, for solitary waves of the derivative CQNLSE with weak disorder in the linear gain both the amplitude and the group velocity β become random. We therefore study analytically and by Monte Carlo simulations the PDF of the parameter p , where p=η/(1-ɛsβ/2) and ɛs is the self-steepening coefficient. Our analytic calculations and numerical simulations show that the PDF of p is loglognormally divergent near the maximum p value.
Solitary wave solutions to nonlinear evolution equations in ...
Indian Academy of Sciences (India)
where u(x,y,t) is a travelling wave solution of nonlinear partial differential equation. We use the ... The ordinary differential equation (9) is then integrated as long as all terms contain derivatives, where we neglect ...... In addition to deterministic perturbation terms, stochastic perturbation terms will also be taken into account.
Bacterial population solitary waves can defeat rings of funnels
International Nuclear Information System (INIS)
Morris, Ryan J; Phan, Trung V; Austin, Robert H; Black, Matthew; Bos, Julia A; Lin, Ke-Chih; Kevrekidis, Ioannis G
2017-01-01
We have constructed a microfabricated circular corral for bacteria made of rings of concentric funnels which channel motile bacteria outwards via non-hydrodynamic interactions with the funnel walls. Initially bacteria do move rapidly outwards to the periphery of the corral. At the edge, nano-slits allow for the transport of nutrients into the device while keeping the bacteria from escaping. After a period of time in which the bacteria increase their cell density in this perimeter region, they are then able to defeat the physical constrains of the funnels by launching back-propagating collective waves. We present the basic data and some nonlinear modeling which can explain how bacterial population waves propagate through a physical funnel, and discuss possible biological implications. (paper)
Solitary wave solution to a singularly perturbed generalized Gardner ...
Indian Academy of Sciences (India)
2017-03-24
Mar 24, 2017 ... This paper is concerned with the existence of travelling wave solutions to a singularly perturbed gen- eralized Gardner equation .... will be used in §3 for our purpose. For convenience, we use a version of this theory due to Jones [2]. For the system. { x (t) = f (x, y, ε), y (t) = εg(x, y, ε),. (2.1) where x ∈ Rn, y ...
Effect of Different Size Dust Grains on the Properties of Solitary Waves in Space Environments
International Nuclear Information System (INIS)
Elwakil, S.A.; Zahran, M.A.; El-Shewy, E.K.; Abdelwahed, H.G.
2009-01-01
Propagation of nonlinear dust-acoustic (DA) waves in an unmagnetized collisionless dusty plasma consisting of dust grains obey power law dust size distribution and nonthermal ions are investigated. For nonlinear DA waves, a reductive perturbation method was employed to obtain a Korteweg-de Vries (KdV) equation for the first-order potential. The effects of a dust size distribution, dust radius and the non-thermal distribution of ions on the soliton amplitude, width and energy of electrostatic solitary structures are presented
Sabry, R.; Omran, M. A.
2013-04-01
Investigation of nonlinear wave modulation of electron-acoustic solitary wave packets in planar as well as nonplanar geometry is carried out for an unmagnetized two temperature plasma composed of cold and hot (featuring q-nonextensive distribution) electrons with stationary ions. It is shown that in such plasma, propagation of EA wave packets is governed by a modified NLSE which accounts for the geometrical effect and the nonextensivity of the hot electron species. It is found that the nature of the modulational instabilities would be significantly modified due to the geometrical effects, density ratio α of the hot-to-cold electrons species as well as their temperature ratio θ. Also, there exists a modulation instability period for the cylindrical and spherical envelope excitations, which does not exist in the one-dimensional case. Furthermore, spherical EA solitary wave packets are more structurally stable to perturbations than the cylindrical ones. The relevance of the current study to EA wave modulation in auroral zone plasma is highlighted.
International Nuclear Information System (INIS)
Roy Choudhury, S.
2007-01-01
The Ostrovsky equation is an important canonical model for the unidirectional propagation of weakly nonlinear long surface and internal waves in a rotating, inviscid and incompressible fluid. Limited functional analytic results exist for the occurrence of one family of solitary-wave solutions of this equation, as well as their approach to the well-known solitons of the famous Korteweg-de Vries equation in the limit as the rotation becomes vanishingly small. Since solitary-wave solutions often play a central role in the long-time evolution of an initial disturbance, we consider such solutions here (via the normal form approach) within the framework of reversible systems theory. Besides confirming the existence of the known family of solitary waves and its reduction to the KdV limit, we find a second family of multihumped (or N-pulse) solutions, as well as a continuum of delocalized solitary waves (or homoclinics to small-amplitude periodic orbits). On isolated curves in the relevant parameter region, the delocalized waves reduce to genuine embedded solitons. The second and third families of solutions occur in regions of parameter space distinct from the known solitary-wave solutions and are thus entirely new. Directions for future work are also mentioned
El-Labany, S. K.; Sabry, R.; El-Taibany, W. F.; Elghmaz, E. A.
2010-04-01
Properties of small amplitude nonlinear ion-acoustic solitary waves in a warm magneto plasma with positive-negative ions and nonthermal electrons are investigated. For this purpose, the hydrodynamic equations for the positive-negative ions, nonthermal electron density distribution, and the Poisson equation are used to derive the corresponding nonlinear evolution equation; Zkharov-Kuznetsov (ZK) equation, in the small amplitude regime. The ZK equation is analyzed to examine the existence regions of the solitary pulses. It is found that compressive and rarefactive ion-acoustic solitary waves strongly depend on the mass and density ratios of the positive and negative ions as well as the nonthermal electron parameter. Also, it is found that there are two critical values for the density ratio of the negative-to-positive ions (υ), the ratio between unperturbed electron-to-positive ion density (μ), and the nonthermal electron parameter (β), which decide the existence of positive and negative ion-acoustic solitary waves. The present study is applied to examine the small amplitude nonlinear ion-acoustic solitary excitations for the (H+, O2-) and (H+, H-) plasmas, where they are found in the D- and F-regions of the Earth's ionosphere. This investigation should be helpful in understanding the salient features of the nonlinear ion-acoustic solitary waves in space and in laboratory plasmas where two distinct groups of ions and non-Boltzmann distributed electrons are present.
Exact periodic and solitary waves and their interactions for the (2+1)-dimensional KdV equation
International Nuclear Information System (INIS)
Peng Yanze
2006-01-01
A general solution involving three arbitrary functions is first obtained for a (2+1)-dimensional KdV equation by means of WTC truncation method. Then exact periodic wave solutions are expressed in terms of rational functions of the Jacobi elliptic functions. Limit cases are studied and some interesting, new solitary structures are revealed. The interaction properties between Jacobi elliptic waves (various limit cases) are investigated numerically. The fusion and fission of y-periodic solitary waves is for the first time reported
International Nuclear Information System (INIS)
Abbasbandy, S.
2009-01-01
Solitary wave solutions to the modified form of Camassa-Holm (CH) equation are sought. In this work, the homotopy analysis method (HAM), one of the most effective method, is applied to obtain the soliton wave solutions with and without continuity of first derivatives at crest
Elastic wavelets and their application to problems of solitary wave propagation
Directory of Open Access Journals (Sweden)
Cattani, Carlo
2008-03-01
Full Text Available The paper can be referred to that direction in the wavelet theory, which was called by Kaiser "the physical wavelets". He developed the analysis of first two kinds of physical wavelets - electromagnetic (optic and acoustic wavelets. Newland developed the technique of application of harmonic wavelets especially for studying the harmonic vibrations. Recently Cattani and Rushchitsky proposed the 4th kind of physical wavelets - elastic wavelets. This proposal was based on three main elements: 1. Kaiser's idea of constructing the physical wavelets on the base of specially chosen (admissible solutions of wave equations. 2. Developed by one of authors theory of solitary waves (with profiles in the form of Chebyshov-Hermite functions propagated in elastic dispersive media. 3. The theory and practice of using the wavelet "Mexican Hat" system, the mother and farther wavelets (and their Fourier transforms of which are analytically represented as the Chebyshov-Hermite functions of different indexes. An application of elastic wavelets to studying the evolution of solitary waves of different shape during their propagation through composite materials is shown on many examples.
Polarons as stable solitary wave solutions to the Dirac-Coulomb system
Comech, Andrew; Zubkov, Mikhail
2013-11-01
We consider solitary wave solutions to the Dirac-Coulomb system both from physical and mathematical points of view. Fermions interacting with gravity in the Newtonian limit are described by the model of Dirac fermions with the Coulomb attraction. This model also appears in certain condensed matter systems with emergent Dirac fermions interacting via optical phonons. In this model, the classical soliton solutions of equations of motion describe the physical objects that may be called polarons, in analogy to the solutions of the Choquard equation. We develop analytical methods for the Dirac-Coulomb system, showing that the no-node gap solitons for sufficiently small values of charge are linearly (spectrally) stable.
Malaspina, David M.; Newman, David L.; Wilson, Lynn Bruce; Goetz, Keith; Kellogg, Paul J.; Kerstin, Kris
2013-01-01
A strong spatial association between bipolar electrostatic solitary waves (ESWs) and magnetic current sheets (CSs) in the solar wind is reported here for the first time. This association requires that the plasma instabilities (e.g., Buneman, electron two stream) which generate ESWs are preferentially localized to solar wind CSs. Distributions of CS properties (including shear angle, thickness, solar wind speed, and vector magnetic field change) are examined for differences between CSs associated with ESWs and randomly chosen CSs. Possible mechanisms for producing ESW-generating instabilities at solar wind CSs are considered, including magnetic reconnection.
Semi-analytic variable charge solitary waves involving dust phase-space vortices (holes)
Energy Technology Data Exchange (ETDEWEB)
Tribeche, Mouloud; Younsi, Smain; Amour, Rabia; Aoutou, Kamel [Plasma Physics Group, Faculty of Sciences-Physics, Theoretical Physics Laboratory, University of Bab-Ezzouar, USTHB BP 32, El Alia, Algiers 16111 (Algeria)], E-mail: mtribeche@usthb.dz
2009-09-15
A semi-analytic model for highly nonlinear solitary waves involving dust phase-space vortices (holes) is outlined. The variable dust charge is expressed in terms of the Lambert function and we take advantage of this transcendental function to investigate the localized structures that may occur in a dusty plasma with variable charge trapped dust particles. Our results which complement the previously published work on this problem (Schamel et al 2001 Phys. Plasmas 8 671) should be of basic interest for experiments that involve the trapping of dust particles in ultra-low-frequency dust acoustic modes.
Semi-analytic variable charge solitary waves involving dust phase-space vortices (holes)
International Nuclear Information System (INIS)
Tribeche, Mouloud; Younsi, Smain; Amour, Rabia; Aoutou, Kamel
2009-01-01
A semi-analytic model for highly nonlinear solitary waves involving dust phase-space vortices (holes) is outlined. The variable dust charge is expressed in terms of the Lambert function and we take advantage of this transcendental function to investigate the localized structures that may occur in a dusty plasma with variable charge trapped dust particles. Our results which complement the previously published work on this problem (Schamel et al 2001 Phys. Plasmas 8 671) should be of basic interest for experiments that involve the trapping of dust particles in ultra-low-frequency dust acoustic modes.
On the generation of solitary waves observed by Cluster in the near-Earth magnetosheath
Czech Academy of Sciences Publication Activity Database
Pickett, J. S.; Chen, L. J.; Kahler, S. W.; Santolík, Ondřej; Goldstein, M. L.; Lavraud, B.; Décréau, P. M. E.; Kessel, R.; Lucek, E.; Lakhina, G. S.; Tsurutani, B. T.; Gurnett, D. A.; Cornilleau-Wehrlin, N.; Fazakerley, A.; Rème, H.; Balogh, A.
2005-01-01
Roč. 12, - (2005), s. 181-193 ISSN 1023-5809 R&D Projects: GA MŠk(CZ) ME 650; GA ČR(CZ) GA202/03/0832; GA MŠk(CZ) 1P05ME811 Grant - others: NASA GSFC(US) NAG5-9974; NASA GSFC(US) NNG04GB98G; NSF(US) ATM 03-27450; NSF(US) 0307319; ESA PECS(XE) 98025 Institutional research plan: CEZ:AV0Z30420517 Keywords : solitary waves * Cluster * near-Earth magnetosheath Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.464, year: 2005
Nonlinear propagation of dust-acoustic solitary waves in a dusty ...
Indian Academy of Sciences (India)
Dust-acoustic solitary waves in a dusty plasma. Now, using eqs (13)–(15) one can easily eliminate (∂n(2) d /∂ξ), (∂u(2) d /∂ξ), and. (∂φ(2)/∂ξ), and obtain. ∂φ(1). ∂τ. + A. √ φ(1). ∂φ(1). ∂ξ. + B. ∂3φ(1). ∂ξ3. = 0,. (16) where. A = 3γ. 4 vp. (μe + αμi). ,. (17). B = vp. 2(μe + αμi) . (18). Equation (16) is a mKdV equation for ...
Papoutsellis, Christos; Athanassoulis, Gerassimos; Charalampopoulos, Alexis-Tzianni
2017-04-01
In this work, we investigate the transformations that solitary surface waves undergo during their interaction with uneven seabed and/or fully reflective vertical boundaries. This is accomplished by performing simulations using a non-local Hamiltonian formulation, taking into account full nonlinearity and dispersion, in the presence of variable seabed [1]. This formulation is based on an exact coupled-mode representation of the velocity potential, leading to efficient and accurate computations of the Dirichlet to Neumann operator, required in Zakharov/Craig-Sulem formulation [2], [3]. In addition, it allows for the efficient computation of wave kinematics (velocity, acceleration) and the pressure field, in the time-dependent fluid domain, up to its physical boundaries. Such computations are performed for the case of high-amplitude solitary waves interacting with varying bathymetry and/or a vertical wall, shedding light to their kinematics and dynamics. More specifically, we first consider two benchmark cases, namely the transformation of solitary waves over a plane beach [4], and the reflection of solitary waves on a vertical wall [5]. As a further step, results on the scattering/reflection of a solitary wave due to an undulating seabed, and on the disintegration of a solitary wave travelling form shallow to deep water are also presented. References:[1] G.A. Athanassoulis. & Ch.E. Papoutsellis, in Volume 7: Ocean Engineering, ASME, OMAE2015-41452, p. V007T06A029 (2015)[2] W. Craig, C. Sulem, J. Comp. Phys. 108, 73-83 (1993) [3] V. Zakharov, J. Appl. Mech. Tech. Phys 9, 86-94 (1968)[4] S. Grilli, R. Subramanya, T. Svendsen. & J. Veeramony, J. Waterway, Port, Coastal, Ocean Eng. 120(6), 609-628. (1994)[5] Y.Y. Chen, C. Kharif , J.H. Yang, H.C. Hsu, J. Touboul & J. Chambarel, Eur. J. Mech B-Fluid 49, 20-28 (2015)
Experimental Study of Solitary Waves Run-up on Rough Slopes
Huang, Kang-wei; Wu, Yun-Ta; Hwung, Hwung-Hweng; Yang, Ray-Yeng
2017-04-01
Long waves close to the shore caused damage were a crucial issue for coastal engineering community. There is a classic issue of long-wave run-up on smooth beaches, which has been extensively studied in literature, using different research methodologies, but in reality, coastal beaches should have surface roughness instead of being hydraulically smooth. Run-up of roughness effect is rarely discussed. In this study, new experiment has been carried out in a laboratory tank (21m x 0.7m x 0.5m) to investigate the physical process of long-wave on a 1:20 slope. Long-wave is with infinite wavelength and wave period. Solitary-wave is employed to represent the characteristic. There are four slopes including smooth, sandpaper, marble, and carpet, the water depths are 16cm (on marble slope), 15cm, 14cm, 12cm and 10cm. The nonlinearity (H/ho) are from 0.04 to 0.451. Firstly, the run-up of long-wave was observed on different slopes. From the comparison in terms of maximum run-up height (R) with different wave-height-to-water-depth ratios were generally categorized into two groups, marble and carpet slopes led to the similar run-up trend. The run up values were by using image processing method to compare average interval 0.05cm and the point at the maximum run-up to find out the sidewall effect. Also using run-up values describe the roughness effect of the run-up reduction. Secondly, the effect of slope roughness was limited on the free surface elevations. The last result, through using a state-of-the-art measuring technique Bubble Image Velocimetry, which features non-intrusive and image-based measurement, the wave kinematics in the highly aerated region with different roughness slopes due to solitary-wave shoaling, breaking and uprush can be quantitated. In order to observe more detail, the high speed camera is used capture the run-up and rundown process. This study can give a reference to the long-wave run-up at the shoreline. It is hoped that more run-up studies will be
Akbar, M Ali; Hj Mohd Ali, Norhashidah
2014-01-01
The exp(-Ф(η))-expansion method is an ascending method for obtaining exact and solitary wave solutions for nonlinear evolution equations. In this article, we implement the exp(-Ф(η))-expansion method to build solitary wave solutions to the fourth order Boussinesq equation. The procedure is simple, direct and useful with the help of computer algebra. By using this method, we obtain solitary wave solutions in terms of the hyperbolic functions, the trigonometric functions and elementary functions. The results show that the exp(-Ф(η))-expansion method is straightforward and effective mathematical tool for the treatment of nonlinear evolution equations in mathematical physics and engineering. 35C07; 35C08; 35P99.
Sabry, R.; Moslem, W. M.; Shukla, P. K.
2009-03-01
Properties of fully nonlinear ion-acoustic solitary waves in a plasma with positive-negative ions and nonthermal electrons are investigated. For this purpose, the hydrodynamic equations for the positive-negative ions, nonthermal electron density distribution, and the Poisson equation are used to derive the energy integral equation with a new Sagdeev potential. The latter is analyzed to examine the existence regions of the solitary pulses. It is found that the solitary excitations strongly depend on the mass and density ratios of the positive and negative ions as well as the nonthermal electron parameter. Numerical solution of the energy integral equation clears that both positive and negative potentials exist together. It is found that faster solitary pulses are taller and narrower. Furthermore, increasing the electron nonthermality parameter (negative-to-positive ions density ratio) decreases (increases) the localized excitation amplitude but increases (decreases) the pulse width. The present model is used to investigate the solitary excitations in the (H+,O2-) and (H+,H-) plasmas, where they are presented in the D- and F-regions of the Earth's ionosphere. This investigation should be helpful in understanding the salient features of the fully nonlinear ion-acoustic solitary waves in space and in laboratory plasmas where two distinct groups of ions and non-Boltzmann distributed electrons are present.
Vortex shedding induced by a solitary wave propagating over a submerged vertical plate
International Nuclear Information System (INIS)
Lin Chang; Ho, T.-C.; Chang, S.-C.; Hsieh, S.-C.; Chang, K.-A.
2005-01-01
Experimental study was conducted on the vortex shedding process induced by the interaction between a solitary wave and a submerged vertical plate. Particle image velocimetry (PIV) was used for quantitative velocity measurement while a particle tracing technique was used for qualitative flow visualization. Vortices are generated at the tip of each side of the plate. The largest vortices at each side of the plate eventually grow to the size of the water depth. Although the fluid motion under the solitary wave is only translatory, vortices are shed in both the upstream and downstream directions due to the interaction of the generated vortices as well as the vortices with the plate and the bottom. The process can be divided into four phases: the formation of a separated shear layer, the generation and shedding of vortices, the formation of a vertical jet, and the impingement of the jet onto the free surface. Similarity velocity profiles were found both in the separated shear layer and in the vertical jet
International Nuclear Information System (INIS)
El-Taibany, W.F.; Sabry, R.
2005-01-01
The effect of nonthermal ions and variable dust charge on small-amplitude nonlinear dust-acoustic (DA) waves is investigated. It is found that both compressive and rarefactive solitons exist and depend on the nonthermal parameter a. Using a reductive perturbation theory, a Zakharov-Kuznetsov (ZK) equation is derived. At critical value of a, a c , a modified ZK equation with third- and fourth-order nonlinearities, is obtained. Depending on a, the solution of the evolution equation reveals whether there is coexistence of both compressive and rarefactive solitary waves or double layers (DLs) with the possibility of their two kinds. In addition, for certain plasma parameters, the solitary wave disappears and a DL is expected. The variation of dust charge number, wave velocity, and soliton amplitude and its width against system parameters is investigated for the DA solitary waves. It is shown that the incorporation of both the adiabatic dust-charge variation and the nonthermal distributed ions modifies significantly the nature of DA solitary waves and DA DLs. The findings of this investigation may be useful in understanding the ion acceleration mechanisms close to the Moon and also enhances our knowledge on pickup ions around unmagnetized bodies, such as comets, Mars, and Venus
Sabry, R.; Moslem, W. M.; Shukla, P. K.
2009-02-01
Ion-acoustic envelope solitary waves in a very dense plasma comprised of the electrons, positrons and ions are investigated. For this purpose, the quantum hydrodynamic model and the Poisson equation are used. A modified nonlinear Schrödinger equation is derived by employing the reductive perturbation method. The effects of the quantum correction and of the positron density on the propagation and stability of the envelope solitary waves are examined. The nonplanar (cylindrical/spherical) geometry gives rise to an instability period. The latter cannot exist for planar case and it affected by the quantum parameters, as well as the positron density. The present investigation is relevant to white dwarfs.
Seismic, satellite, and site observations of internal solitary waves in the NE South China Sea.
Tang, Qunshu; Wang, Caixia; Wang, Dongxiao; Pawlowicz, Rich
2014-06-20
Internal solitary waves (ISWs) in the NE South China Sea (SCS) are tidally generated at the Luzon Strait. Their propagation, evolution, and dissipation processes involve numerous issues still poorly understood. Here, a novel method of seismic oceanography capable of capturing oceanic finescale structures is used to study ISWs in the slope region of the NE SCS. Near-simultaneous observations of two ISWs were acquired using seismic and satellite imaging, and water column measurements. The vertical and horizontal length scales of the seismic observed ISWs are around 50 m and 1-2 km, respectively. Wave phase speeds calculated from seismic observations, satellite images, and water column data are consistent with each other. Observed waveforms and vertical velocities also correspond well with those estimated using KdV theory. These results suggest that the seismic method, a new option to oceanographers, can be further applied to resolve other important issues related to ISWs.
Solitary Wave Solutions of the Boussinesq Equation and Its Improved Form
Directory of Open Access Journals (Sweden)
Reza Abazari
2013-01-01
Full Text Available This paper presents the general case study of previous works on generalized Boussinesq equations, (Abazari, 2011 and (Kılıcman and Abazari, 2012, that focuses on the application of G′/G-expansion method with the aid of Maple to construct more general exact solutions for the coupled Boussinesq equations. In this work, the mentioned method is applied to construct more general exact solutions of Boussinesq equation and improved Boussinesq equation, which the French scientist Joseph Valentin Boussinesq (1842–1929 described in the 1870s model equations for the propagation of long waves on the surface of water with small amplitude. Our work is motivated by the fact that the G′/G-expansion method provides not only more general forms of solutions but also periodic, solitary waves and rational solutions. The method appears to be easier and faster by means of a symbolic computation.
Seadawy, A. R.; El-Rashidy, K.
2018-03-01
The Kadomtsev-Petviashvili (KP) and modified KP equations are two of the most universal models in nonlinear wave theory, which arises as a reduction of system with quadratic nonlinearity which admit weakly dispersive waves. The generalized extended tanh method and the F-expansion method are used to derive exact solitary waves solutions of KP and modified KP equations. The region of solutions are displayed graphically.
Jia, T.; Liang, J. J.; Li, X.-M.; Sha, J.
2018-01-01
The refraction and reconnection of internal solitary waves (ISWs) around the Dongsha Atoll (DSA) in the northern South China Sea (SCS) are investigated based on spaceborne synthetic aperture radar (SAR) observations and numerical simulations. In general, a long ISW front propagating from the deep basin of the northern SCS splits into northern and southern branches when it passes the DSA. In this study, the statistics of Envisat Advanced SAR (ASAR) images show that the northern and southern wave branches can reconnect behind the DSA, but the reconnection location varies. A previously developed nonlinear refraction model is set up to simulate the refraction and reconnection of the ISWs behind the DSA, and the model is used to evaluate the effects of ocean stratification, background currents, and incoming ISW characteristics at the DSA on the variation in reconnection locations. The results of the first realistic simulation agree with consecutive TerraSAR-X (TSX) images captured within 12 h of each other. Further sensitivity simulations show that ocean stratification, background currents, and initial wave amplitudes all affect the phase speeds of wave branches and therefore shift their reconnection locations while shapes and locations of incoming wave branches upstream of the DSA profoundly influence the subsequent propagation paths. This study clarifies the variation in reconnection locations of ISWs downstream of the DSA and reveals the important mechanisms governing the reconnection process, which can improve our understanding of the propagation of ISWs near the DSA.
Salmanpoor, H.; Sharifian, M.; Gholipour, S.; Borhani Zarandi, M.; Shokri, B.
2018-03-01
The oblique propagation of nonlinear ion acoustic solitary waves (solitons) in magnetized collisionless and weakly relativistic plasma with positive and negative ions and super thermal electrons has been examined by using reduced perturbation method to obtain the Korteweg-de Vries equation that admits an obliquely propagating soliton solution. We have investigated the effects of plasma parameters like negative ion density, electrons temperature, angle between wave vector and magnetic field, ions velocity, and k (spectral index in kappa distribution) on the amplitude and width of solitary waves. It has been found out that four modes exist in our plasma model, but the analysis of the results showed that only two types of ion acoustic modes (fast and slow) exist in the plasma and in special cases only one mode could be propagated. The parameters of plasma for these two modes (or one mode) determine which one is rarefactive and which one is compressive. The main parameter is negative ions density (β) indicating which mode is compressive or rarefactive. The effects of the other plasma parameters on amplitude and width of the ion acoustic solitary waves have been studied. The main conclusion is that the effects of the plasma parameters on amplitude and width of the solitary wave strongly depend on the value of the negative ion density.
Bedforms induced by solitary waves: laboratory studies on generation and migration rate
la Forgia, Giovanni; Adduce, Claudia; Falcini, Federico; Paola, Chris
2017-04-01
This study presents experiments on the formation of sandy bedforms, produced by surface solitary waves (SSWs) in shallow water conditions. The experiments were carried out in a 12.0 m long, 0.15 m wide and 0.5 m high flume, at Saint Anthony Falls Laboratory in Minneapolis. The tank is filled by fresh water and a removable gate, placed at the left hand-side of the tank, divides the flume in two regions: the lock region and the ambient fluid region. The standard lock-release method generates SSWs by producing a displacement between the free surfaces that are divided by the gate. Wave amplitude, wavelength, and celerity depend on the lock length and on the water level difference between the two regions. Natural sand particles (D50=0.64) are arranged on the bottom in order to form a horizontal flat layer with a thickness of 2 cm. A digital pressure gauge and a high-resolution acoustic velocimeter allowed us to measure, locally, both pressure and 3D water velocity induced on the bottom by each wave. Image analysis technique is then used to obtain the main wave features: amplitude, wavelength, and celerity. Dye is finally used as vertical tracer to mark the horizontal speed induced by the wave. For each experiment we generated 400 waves, having the same features and we analyzed their action on sand particles placed on the bottom. The stroke, induced by each wave, entails a shear stress on the sand particles, causing sediment transport in the direction of wave propagation. Immediately after the wave passage, a back flow occurs near the bottom. The horizontal pressure gradient and the velocity field induced by the wave cause the boundary layer separation and the consequent reverse flow. Depending on the wave features and on the water depth, the boundary shear stress induced by the reverse flow can exceed the critical value inducing the back motion of the sand particles. The experiments show that the particle back motion is localized at particular cross sections along the
A Solitary Wave-Based Sensor to Monitor the Setting of Fresh Concrete
Directory of Open Access Journals (Sweden)
Piervincenzo Rizzo
2014-07-01
Full Text Available We present a proof-of-principle study about the use of a sensor for the nondestructive monitoring of strength development in hydrating concrete. The nondestructive evaluation technique is based on the propagation of highly nonlinear solitary waves (HNSWs, which are non-dispersive mechanical waves that can form and travel in highly nonlinear systems, such as one-dimensional particle chains. A built-in transducer is adopted to excite and detect the HNSWs. The waves are partially reflected at the transducer/concrete interface and partially transmitted into the concrete. The time-of-flight and the amplitude of the waves reflected at the interface are measured and analyzed with respect to the hydration time, and correlated to the initial and final set times established by the penetration test (ASTM C 403. The results show that certain features of the HNSWs change as the concrete curing progresses indicating that it has the potential of being an efficient, cost-effective tool for monitoring strengths/stiffness development.
Response of internal solitary waves to tropical storm Washi in the northwestern South China Sea
Directory of Open Access Journals (Sweden)
Z. H. Xu
2011-11-01
Full Text Available Based on in-situ time series data from an array of temperature sensors and an acoustic Doppler current profiler on the continental shelf of the northwestern South China Sea, a sequence of internal solitary waves (ISWs were observed during the passage of tropical storm Washi in the summer of 2005, which provided a unique opportunity to investigate the ISW response to the tropical cyclone. The passing tropical storm is found to play an important role in affecting the stratification structure of the water column, and consequently leading to significant variability in the propagating features of the ISWs, such as the polarity reversal and amplitude variations of the waves. The response of the ISWs to Washi can be divided into two stages, direct forcing by the strong wind (during the arrival of Washi and remote forcing via the near-inertial internal waves induced by the tropical storm (after the passage of Washi. The field observations as well as a theoretical analysis suggest that the variations of the ISWs closely coincide with the changing stratification structure and shear currents in accompanied by the typhoon wind and near-inertial waves. This study presents the first observations and analysis of the ISW response to the tropical cyclone in the South China Sea.
Hossen, M. R.; Nahar, L.; Sultana, S.; Mamun, A. A.
2014-09-01
The properties of heavy-ion-acoustic (HIA) solitary structures associated with the nonlinear propagation of cylindrical and spherical electrostatic perturbations in an unmagnetized, collisionless dense plasma system has been investigated theoretically. Our considered model contains degenerate electron and inertial light ion fluids, and positively charged static heavy ions, which is valid for both of the non-relativistic and ultra-relativistic limits. The Korteweg-de Vries (K-dV) and modified K-dV (mK-dV) equations have been derived by employing the reductive perturbation method, and numerically examined in order. It has been found that the effect of degenerate pressure and number density of electron and inertial light ion fluids, and positively charged static heavy ions significantly modify the basic features of HIA solitary waves. It is also noted that the inertial light ion fluid is the source of dispersion for HIA waves and is responsible for the formation of solitary waves. The basic features and the underlying physics of HIA solitary waves, which are relevant to some astrophysical compact objects, are briefly discussed.
Mapping Electrostatic Solitary Wave Activity in the Bursty Bulk Flow Braking Region
Hansel, P. J.; Wilder, F. D.; Malaspina, D.; Ergun, R.; Holmes, J.; Ahmadi, N.; Goodrich, K.; Burch, J.; Torbert, R. B.; Giles, B. L.; Fuselier, S. A.; Russell, C. T.; Strangeway, R. J.; Lindqvist, P. A.; Khotyaintsev, Y. V.
2017-12-01
Electrostatic solitary waves (ESWs) are plasma structures generally defined by their uniquely bipolar electric fields and propagation parallel to the local magnetic field at approximately the electron thermal velocity. Formation mechanisms for ESWs in the magnetotail have been studied extensively in the past, and are associated with the braking and diversion of bursty bulk flows (BBFs) arising from reconnection at the distant tail region X-line (>25 Re). However, the brief timescales over which ESWs occur (braking region. Proton bulk velocities from the Hot Plasma Composition Analyzer (HPCA) appear to agree with these results. Preliminary analysis additionally shows an unexpectedly high ESW occurrence rate on the dawn side, for which the mechanism is less well-understood.
Lie symmetry analysis, conservation laws, solitary and periodic waves for a coupled Burger equation
Xu, Mei-Juan; Tian, Shou-Fu; Tu, Jian-Min; Zhang, Tian-Tian
2017-01-01
Under investigation in this paper is a generalized (2 + 1)-dimensional coupled Burger equation with variable coefficients, which describes lots of nonlinear physical phenomena in geophysical fluid dynamics, condense matter physics and lattice dynamics. By employing the Lie group method, the symmetry reductions and exact explicit solutions are obtained, respectively. Based on a direct method, the conservations laws of the equation are also derived. Furthermore, by virtue of the Painlevé analysis, we successfully obtain the integrable condition on the variable coefficients, which plays an important role in further studying the integrability of the equation. Finally, its auto-Bäcklund transformation as well as some new analytic solutions including solitary and periodic waves are also presented via algebraic and differential manipulation.
Variational methods in nonlinear field equations solitary waves, hylomorphic solitons and vortices
Benci, Vieri
2014-01-01
The book analyzes the existence of solitons, namely of finite energy solutions of field equations which exhibit stability properties. The book is divided in two parts. In the first part, the authors give an abstract definition of solitary wave and soliton and we develop an abstract existence theory for hylomorphic solitons, namely for those solitons which minimize the energy for a given charge. In the second part, the authors apply this theory to prove the existence of hylomorphic solitons for some classes of field equations (nonlinear Klein-Gordon-Maxwell equations, nonlinear Schrödinger-Maxwell equations, nonlinear beam equation,..). The abstract theory is sufficiently flexible to be applied to other situations, like the existence of vortices. The books is addressed to Mathematicians and Physicists.
Dust ion acoustic solitary waves in a magnetized dusty plasma with anisotropic ion pressure
International Nuclear Information System (INIS)
Choi, Cheong Rim; Ryu, Chang-Mo; Lee, D.-Y.; Lee, Nam C.; Kim, Y.-H.
2007-01-01
The influence of anisotropic ion pressure on the dust ion acoustic solitary wave (DIASW) and the double layer (DL) obliquely propagating to a magnetic field are investigated by using the Sagdeev potential. The anisotropic ion pressure is defined by applying the Chew-Goldberger-Low (CGL) theory, p-perpendicular=p-perpendicular 0 n and p-parallel=p-parallel 0 n 3 , where n is the normalized ion density. The solutions of DIASWs and DLs obliquely propagating to an external magnetic field are obtained in the small amplitude limit. It is found that the perpendicular component of anisotropic ion pressure works differently from that of the parallel component on the DIASWs in a magnetized dusty plasma, deviating from a straight extension of the isotropic pressure effect
Cox, Brian N.; Landis, Chad M.
2018-02-01
We present a simple theory of a strain pulse propagating as a solitary wave through a continuous two-dimensional population of cells. A critical strain is assumed to trigger a strain transformation, while, simultaneously, cells move as automata to tend to restore a preferred cell density. We consider systems in which the strain transformation is a shape change, a burst of proliferation, or the commencement of growth (which changes the shape of the population sheet), and demonstrate isomorphism among these cases. Numerical and analytical solutions describe a strain pulse whose height does not depend on how the strain disturbance was first launched, or the rate at which the strain transformation is achieved, or the rate constant in the rule for the restorative cell motion. The strain pulse is therefore very stable, surviving the imposition of strong perturbations: it would serve well as a timing signal in development. The automatous wave formulation is simple, with few model parameters. A strong case exists for the presence of a strain pulse during amelogenesis. Quantitative analysis reveals a simple relationship between the velocity of the leading edge of the pulse in amelogenesis and the known speed of migration of ameloblast cells. This result and energy arguments support the depiction of wave motion as an automatous cell response to strain, rather than as a response to an elastic energy gradient. The theory may also contribute to understanding the determination front in somitogenesis, moving fronts of convergent-extension transformation, and mitotic wavefronts in the syncytial drosophila embryo.
International Nuclear Information System (INIS)
Dossmann, Yvan; Paci, Alexandre; Auclair, Francis; Lepilliez, Mathieu; Cid, Emmanuel
2014-01-01
Internal solitary waves (ISWs) are large amplitude stable waves propagating in regions of high density gradients such as the ocean pycnocline. Their dynamics has often been investigated in two-dimensional approaches, however, their three-dimensional evolution is still poorly known. Experiments have been conducted in the large stratified water tank of CNRM-GAME to study the generation of ISWs in two academic configurations inspired by oceanic regimes. First, ultrasonic probes are used to measure the interfacial displacement in the two configurations. In the primary generation case for which the two layers are of constant density, the generation of ISWs is investigated in two series of experiments with varying amplitude and forcing frequency. In the secondary generation case for which the lower layer is stratified, the generation of ISWs from the impact of an internal wave beam on the pycnocline and their subsequent dynamics is studied. The dynamics of ISWs in these two regimes accords well with analytical approaches and numerical simulations performed in analogous configurations. Then, recent developments of a stereo correlation technique are used to describe the three-dimensional structure of propagating ISWs. In the primary generation configuration, small transverse effects are observed in the course of the ISW propagation. In the secondary generation configuration, larger transverse structures are observed in the interfacial waves dynamics. The interaction between interfacial troughs and internal waves propagating in the lower stratified layer are a possible cause for the generation of these structures. The magnitude of these transverse structures is quantified with a nondimensional parameter in the two configurations. They are twice as large in the secondary generation case as in the primary generation case
Interactions of solitary waves and compression/expansion waves in core-annular flows
Maiden, Michelle; Anderson, Dalton; El, Gennady; Franco, Nevil; Hoefer, Mark
2017-11-01
The nonlinear hydrodynamics of an initial step leads to the formation of rarefaction waves and dispersive shock waves in dispersive media. Another hallmark of these media is the soliton, a localized traveling wave whose speed is amplitude dependent. Although compression/expansion waves and solitons have been well-studied individually, there has been no mathematical description of their interaction. In this talk, the interaction of solitons and shock/rarefaction waves for interfacial waves in viscous, miscible core-annular flows are modeled mathematically and explored experimentally. If the interior fluid is continuously injected, a deformable conduit forms whose interfacial dynamics are well-described by a scalar, dispersive nonlinear partial differential equation. The main focus is on interactions of solitons with dispersive shock waves and rarefaction waves. Theory predicts that a soliton can either be transmitted through or trapped by the extended hydrodynamic state. The notion of reciprocity is introduced whereby a soliton interacts with a shock wave in a reciprocal or dual fashion as with the rarefaction. Soliton reciprocity, trapping, and transmission are observed experimentally and are found to agree with the modulation theory and numerical simulations. This work was partially supported by NSF CAREER DMS-1255422 (M.A.H.) and NSF GRFP (M.D.M.).
Rao, Chengping; Zhang, Youlin; Wan, Decheng
2017-12-01
Fluid-Structure Interaction (FSI) caused by fluid impacting onto a flexible structure commonly occurs in naval architecture and ocean engineering. Research on the problem of wave-structure interaction is important to ensure the safety of offshore structures. This paper presents the Moving Particle Semi-implicit and Finite Element Coupled Method (MPS-FEM) to simulate FSI problems. The Moving Particle Semi-implicit (MPS) method is used to calculate the fluid domain, while the Finite Element Method (FEM) is used to address the structure domain. The scheme for the coupling of MPS and FEM is introduced first. Then, numerical validation and convergent study are performed to verify the accuracy of the solver for solitary wave generation and FSI problems. The interaction between the solitary wave and an elastic structure is investigated by using the MPS-FEM coupled method.
Inc, Mustafa; Aliyu, Aliyu Isa; Yusuf, Abdullahi; Baleanu, Dumitru
2018-01-01
This paper addresses the coupled nonlinear Schrödinger equation (CNLSE) in monomode step-index in optical fibers which describes the nonlinear modulations of two monochromatic waves, whose group velocities are almost equal. A class of dark, bright, dark-bright and dark-singular optical solitary wave solutions of the model are constructed using the complex envelope function ansatz. Singular solitary waves are also retrieved as bye products of the in integration scheme. This naturally lead to some constraint conditions placed on the solitary wave parameters which must hold for the solitary waves to exist. The modulation instability (MI) analysis of the model is studied based on the standard linear-stability analysis. Numerical simulation and physical interpretations of the obtained results are demonstrated. It is hoped that the results reported in this paper can enrich the nonlinear dynamical behaviors of the CNLSE.
Collaborative research: Dynamics of electrostatic solitary waves and their effects on current layers
Energy Technology Data Exchange (ETDEWEB)
Chen, Li-Jen
2014-04-18
The project has accomplished the following achievements including the goals outlined in the original proposal. Generation and measurements of Debye-scale electron holes in laboratory: We have generated by beam injections electron solitary waves in the LAPD experiments. The measurements were made possible by the fabrication of the state-of-the-art microprobes at UCLA to measure Debye-scale electric fields [Chiang et al., 2011]. We obtained a result that challenged the state of knowledge about electron hole generation. We found that the electron holes were not due to two-stream instability, but generated by a current-driven instability that also generated whistler-mode waves [Lefebvre et al., 2011, 2010b]. Most of the grant supported a young research scientist Bertrand Lefebvre who led the dissemination of the laboratory experimental results. In addition to two publications, our work relevant to the laboratory experiments on electron holes has resulted in 7 invited talks [Chen, 2007, 2009; Pickett et al., 2009a; Lefebvre et al., 2010a; Pickett et al., 2010; Chen et al., 2011c, b] (including those given by the co-I Jolene Pickett) and 2 contributed talks [Lefebvre et al., 2009b, a]. Discovery of elecctron phase-space-hole structure in the reconnection electron layer: Our theoretical analyses and simulations under this project led to the discovery of an inversion electric field layer whose phase-space signature is an electron hole within the electron diffusion layer in 2D anti-parallel reconnection [Chen et al., 2011a]. We carried out particle tracing studies to understand the electron orbits that result in the phase-space hole structure. Most importantly, we showed that the current density in the electron layer is limited in collisionless reconnection with negligible guide field by the cyclotron turning of meandering electrons. Comparison of electrostatic solitary waves in current layers observed by Cluster and in LAPD: We compared the ESWs observed in a supersubstorm
Single-peak solitary wave solutions for the variant Boussinesq ...
Indian Academy of Sciences (India)
Zhang and Chen [6] obtained new types of cusped solitons of a partial differential equation by setting the partial differential equation under inhomogeneous .... (ii) For g = 0. If ψ(0) = 0, by eq. (2.8) we know ψ (0) exists. According to the definition of peak point, we have ψ (0) = 0. However, by eq. (2.8) we must have ψ(0) = A, ...
An extreme internal solitary wave event observed in the northern South China Sea.
Huang, Xiaodong; Chen, Zhaohui; Zhao, Wei; Zhang, Zhiwei; Zhou, Chun; Yang, Qingxuan; Tian, Jiwei
2016-07-21
With characteristics of large amplitude and strong current, internal solitary wave (ISW) is a major hazard to marine engineering and submarine navigation; it also has significant impacts on marine ecosystems and fishery activity. Among the world oceans, ISWs are particular active in the northern South China Sea (SCS). In this spirit, the SCS Internal Wave Experiment has been conducted since March 2010 using subsurface mooring array. Here, we report an extreme ISW captured on 4 December 2013 with a maximum amplitude of 240 m and a peak westward current velocity of 2.55 m/s. To the authors' best knowledge, this is the strongest ISW of the world oceans on record. Full-depth measurements also revealed notable impacts of the extreme ISW on deep-ocean currents and thermal structures. Concurrent mooring measurements near Batan Island showed that the powerful semidiurnal internal tide generation in the Luzon Strait was likely responsible for the occurrence of the extreme ISW event. Based on the HYCOM data-assimilation product, we speculate that the strong stratification around Batan Island related to the strengthening Kuroshio may have contributed to the formation of the extreme ISW.
Landau damping effects on dust-acoustic solitary waves in a dusty negative-ion plasma
Energy Technology Data Exchange (ETDEWEB)
Barman, Arnab; Misra, A. P., E-mail: apmisra@visva-bharati.ac.in, E-mail: apmisra@gmail.com [Department of Mathematics, Siksha Bhavana, Visva-Bharati University, Santiniketan 731 235, West Bengal (India)
2014-07-15
The nonlinear theory of dust-acoustic waves (DAWs) with Landau damping is studied in an unmagnetized dusty negative-ion plasma in the extreme conditions when the free electrons are absent. The cold massive charged dusts are described by fluid equations, whereas the two-species of ions (positive and negative) are described by the kinetic Vlasov equations. A Korteweg-de Vries (KdV) equation with Landau damping, governing the dynamics of weakly nonlinear and weakly dispersive DAWs, is derived following Ott and Sudan [Phys. Fluids 12, 2388 (1969)]. It is shown that for some typical laboratory and space plasmas, the Landau damping (and the nonlinear) effects are more pronounced than the finite Debye length (dispersive) effects for which the KdV soliton theory is not applicable to DAWs in dusty pair-ion plasmas. The properties of the linear phase velocity, solitary wave amplitudes (in presence and absence of the Landau damping) as well as the Landau damping rate are studied with the effects of the positive ion to dust density ratio (μ{sub pd}) as well as the ratios of positive to negative ion temperatures (σ) and masses (m)
Large-amplitude internal tides, solitary waves, and turbulence in the central Bay of Biscay
Xie, X. H.; Cuypers, Y.; Bouruet-Aubertot, P.; Ferron, B.; Pichon, A.; LourençO, A.; Cortes, N.
2013-06-01
and fine-scale measurements collected in the central Bay of Biscay during the MOUTON experiment are analyzed to investigate the dynamics of internal waves and associated mixing. Large-amplitude internal tides (ITs) that excite internal solitary waves (ISWs) in the thermocline are observed. ITs are dominated by modes 3 and 4, while ISWs projected on mode 1 that is trapped in the thermocline. Therein, ITs generate a persistent narrow shear band, which is strongly correlated with the enhanced dissipation rate in the thermocline. This strong dissipation rate is further reinforced in the presence of ISWs. Dissipation rates during the period without ISWs largely agree with the MacKinnon-Gregg scaling proposed for internal wavefields dominated by a low-frequency mode, while they show poor agreement with the Gregg-Henyey parameterization valid for internal wavefields close to the Garrett-Munk model. The agreement with the MacKinnon-Gregg scaling is consistent with the fact that turbulent mixing here is driven by the low-frequency internal tidal shear.
Buffoni, Boris; Groves, Mark D.; Wahlén, Erik
2017-12-01
Fully localised solitary waves are travelling-wave solutions of the three- dimensional gravity-capillary water wave problem which decay to zero in every horizontal spatial direction. Their existence has been predicted on the basis of numerical simulations and model equations (in which context they are usually referred to as `lumps'), and a mathematically rigorous existence theory for strong surface tension (Bond number {β} greater than {1/3} ) has recently been given. In this article we present an existence theory for the physically more realistic case {0 < β < 1/3} . A classical variational principle for fully localised solitary waves is reduced to a locally equivalent variational principle featuring a perturbation of the functional associated with the Davey-Stewartson equation. A nontrivial critical point of the reduced functional is found by minimising it over its natural constraint set.
On the generation and evolution of internal solitary waves in the southern Red Sea
Guo, Daquan
2016-11-28
Satellite observations recently revealed trains of internal solitary waves (ISWs) in the off-shelf region between 16.0 degrees N and 16.5 degrees N in the southern Red Sea. The generation mechanism of these waves is not entirely clear, though, as the observed generation sites are far away (50 km) from the shelf break and tidal currents are considered relatively weak in the Red Sea. Upon closer examination of the tide properties in the Red Sea and the unique geometry of the basin, it is argued that the steep bathymetry and a relatively strong tidal current in the southern Red Sea provide favorable conditions for the generation of ISWs. To test this hypothesis and further explore the evolution of ISWs in the basin, 2-D numerical simulations with the nonhydrostatic MIT general circulation model (MITgcm) were conducted. The results are consistent with the satellite observations in regard to the generation sites, peak amplitudes and the speeds of first-mode ISWs. Moreover, our simulations suggest that the generation process of ISWs in the southern Red Sea is similar to the tide-topography interaction mechanism seen in the South China Sea. Specifically, instead of ISWs arising in the immediate vicinity of the shelf break via a hydraulic lee wave mechanism, a broad, energetic internal tide is first generated, which subsequently travels away from the shelf break and eventually breaks down into ISWs. Sensitivity runs suggest that ISW generation may also be possible under summer stratification conditions, characterized by an intermediate water intrusion from the strait of Bab el Mandeb.
Shrivastava, Shamit; Schneider, Matthias F
2014-08-06
Biological membranes by virtue of their elastic properties should be capable of propagating localized perturbations analogous to sound waves. However, the existence and the possible role of such waves in communication in biology remain unexplored. Here, we report the first observations of two-dimensional solitary elastic pulses in lipid interfaces, excited mechanically and detected by FRET. We demonstrate that the nonlinearity near a maximum in the susceptibility of the lipid monolayer results in solitary pulses that also have a threshold for excitation. These experiments clearly demonstrate that the state of the interface regulates the propagation of pulses both qualitatively and quantitatively. Finally, we elaborate on the striking similarity of the observed phenomenon to nerve pulse propagation and a thermodynamic basis of cell signalling in general. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Directory of Open Access Journals (Sweden)
Jia Lin Wu
2013-06-01
Full Text Available In macromolecular self-avoiding random walk, movement of each chain-particle accompanies an instantaneous spin system with de Gennes n = 0 that provides extra energy, extra vacancy volume and relaxation time needed for chain-particles co-movement. Using these additional and instantaneous spin systems not only directly yields the same Brownian motion mode in glass transition (GT and reptation-tube model, but also proves that the entangled chain length corresponding to the Reynolds number in hydrodynamics and the inherent diffusion - delocalization mode of entangled chains, from frozen glass state to melt liquid state, is a chain-size solitary wave with transverse ripplon-like soft wave. Thus, the order parameter of GT is found. The various currently available GT theories, such as Static Replica, Random First-Order Transition, Potential Energy Landscape, Mode-Coupling and Nanoscale Heterogeneity, can be unified using the additional and instantaneous spin system. GT served as an inspiration and continues to serve as the paradigm in the universal random delocalization transitions from disorder to more disorder until turbulence.
Directory of Open Access Journals (Sweden)
Zhang Sheng
2015-01-01
Full Text Available In this paper, Painleve analysis is used to test the Painleve integrability of a forced variable-coefficient extended Korteveg-de Vries equation which can describe the weakly-non-linear long internal solitary waves in the fluid with continuous stratification on density. The obtained results show that the equation is integrable under certain conditions. By virtue of the truncated Painleve expansion, a pair of new exact solutions to the equation is obtained.
Directory of Open Access Journals (Sweden)
Harun-Or Roshid
2017-09-01
Full Text Available By using modified simple equation method, we study the generalized RLW equation and symmetric RLW equation, the subsistence of solitary wave, periodic cusp wave, periodic bell wave solutions are obtained. We establish some conditions on the parameters for which the obtained solutions are dark or bright soliton. The proficiency of the methods for constructing exact solutions has been established. Finally, the variety of structure and graphical representation makes the dynamics of the equations visible and provides the mathematical foundation in shallow water, plasma and ion acoustic plasma waves.
Solitary waves in dusty plasmas with weak relativistic effects in electrons and ions
Energy Technology Data Exchange (ETDEWEB)
Kalita, B. C., E-mail: bckalita123@gmail.com [Gauhati University, Department of Mathematics (India); Choudhury, M., E-mail: choudhurymamani@gmail.com [Handique Girls’ College, Department of Mathematics (India)
2016-10-15
Two distinct classes of dust ion acoustic (DIA) solitary waves based on relativistic ions and electrons, dust charge Z{sub d} and ion-to-dust mass ratio Q’ = m{sub i}/m{sub d} are established in this model of multicomponent plasmas. At the increase of mass ratio Q’ due to increase of relativistic ion mass and accumulation of more negative dust charges into the plasma causing decrease of dust mass, relativistic DIA solitons of negative potentials are abundantly observed. Of course, relativistic compressive DIA solitons are also found to exist simultaneously. Further, the decrease of temperature inherent in the speed of light c causes the nonlinear term to be more active that increases the amplitude of the rarefactive solitons and dampens the growth of compressive solitons for relatively low and high mass ratio Q’, respectively. The impact of higher initial streaming of the massive ions is observed to identify the point of maximum dust density N{sub d} to yield rarefactive relativistic solitons of maximum amplitude.
International Nuclear Information System (INIS)
Amour, Rabia; Tribeche, Mouloud
2010-01-01
A first theoretical work is presented to study variable charge dust acoustic solitons within the theoretical framework of the Tsallis statistical mechanics. Our results reveal that the spatial patterns of the variable charge solitary wave are significantly modified by electron nonextensive effects. In particular, it may be noted that for -1 d becomes more negative and the dust grains localization (accumulation) less pronounced. The electrons are locally expelled and pushed out of the region of the soliton's localization. This electron depletion becomes less effective as the electrons evolve far away from their thermal equilibrium. The case q>1 provides qualitatively opposite results: electron nonextensivity makes the solitary structure more spiky. Our results should help in providing a good fit between theoretical and experimental results.
Khater, Mostafa M. A.; Seadawy, Aly R.; Lu, Dianchen
2018-03-01
In this research, we investigate one of the most popular model in nature and also industrial which is the pressure equation of bubbly liquids with examination for viscosity and heat transfer which has many application in nature and engineering. Understanding the physical meaning of exact and solitary traveling wave solutions for this equation gives the researchers in this field a great clear vision of the pressure waves in a mixture liquid and gas bubbles taking into consideration the viscosity of liquid and the heat transfer and also dynamics of contrast agents in the blood flow at ultrasonic researches. To achieve our goal, we apply three different methods which are extended tanh-function method, extended simple equation method and a new auxiliary equation method on this equation. We obtained exact and solitary traveling wave solutions and we also discuss the similarity and difference between these three method and make a comparison between results that we obtained with another results that obtained with the different researchers using different methods. All of these results and discussion explained the fact that our new auxiliary equation method is considered to be the most general, powerful and the most result-oriented. These kinds of solutions and discussion allow for the understanding of the phenomenon and its intrinsic properties as well as the ease of way of application and its applicability to other phenomena.
Directory of Open Access Journals (Sweden)
Sophie S. Shamailov, Joachim Brand
2018-03-01
Full Text Available Superconducting Josephson vortices have direct analogues in ultracold-atom physics as solitary-wave excitations of two-component superfluid Bose gases with linear coupling. Here we numerically extend the zero-velocity Josephson vortex solutions of the coupled Gross-Pitaevskii equations to non-zero velocities, thus obtaining the full dispersion relation. The inertial mass of the Josephson vortex obtained from the dispersion relation depends on the strength of linear coupling and has a simple pole divergence at a critical value where it changes sign while assuming large absolute values. Additional low-velocity quasiparticles with negative inertial mass emerge at finite momentum that are reminiscent of a dark soliton in one component with counter-flow in the other. In the limit of small linear coupling we compare the Josephson vortex solutions to sine-Gordon solitons and show that the correspondence between them is asymptotic, but significant differences appear at finite values of the coupling constant. Finally, for unequal and non-zero self- and cross-component nonlinearities, we find a new solitary-wave excitation branch. In its presence, both dark solitons and Josephson vortices are dynamically stable while the new excitations are unstable.
Directory of Open Access Journals (Sweden)
Shanmugasundaram Rajaian
2010-01-01
Full Text Available Purpose : To evaluate the outcome of shock wave lithotripsy (SWL as monotherapy for solitary renal stones larger than 2 cm without ureteral stenting. Materials and Methods : Our retrospective study included patients with solitary renal radio opaque stones larger than 2 cm treated with SWL using electromagnetic Dornier Compact S lithotripter device (Wessling, Germany for a period of 3 years (September 2002-2005. Stone clearance was assessed at 1 week, 1 month, and 3 months with plain X-rays of kidney, ureter, and bladder region, ultrasonography, and tomograms. Stone-free status, morbidity of the procedure, and fate of clinically insignificant residual fragments (CIRF were studied. A stone-free state was defined as no radiologic evidence of stone. Success was defined as complete clearance + CIRF. Results : Fifty-five patients, aged 11-65 years (mean 49.8 underwent SWL. Of them, only two were children. Male-to-female ratio was 3:1. The stone size was 21-28 mm (average 24 mm. The mean number of shocks were 3732 (range 724-12,100 and average energy level was 14 kV (range 11-16 kV. The mean follow-up was 18 months (range 3-22 months. Over all, stone-free status was achieved in 50% and success in 81% at 3 months. Stone clearance was not affected by stone location. Stones 26 mm (P = -0.10. Of 54 patients, 39 developed steinstrasse with mean length of 3.2 cm (range 1.4-6.2 cm and only four required intervention. Effectiveness quotient (EQ for SWL monotherapy for solitary renal stones more than 2 cm was 25.3%. The EQ for stones <25 mm and those more than 25 mm were 28.4% and 10% (P = -0.12, respectively. There was a lesser trend of difference between stones with size <25 and more than 25 mm. During the last review, the overall stone-free rate was 67.2%. Conclusions : SWL monotherapy was safe but significantly less effective for solitary renal stones larger than 2 cm. It can only be suggested to those who refuse surgical intervention. Pretreatment DJ
New, A. L.; Magalhaes, J. M.; da Silva, J. C. B.
2013-09-01
Energetic Internal Solitary Waves (ISWs) were recently discovered radiating from the central region of the Mascarene Plateau in the south-western Indian Ocean (da Silva et al., 2011). SAR imagery revealed the two-dimensional structure of the waves which propagated for several hundred kilometres in deep water both to the east and west of a sill, located near 12.5°S, 61°E between the Saya de Malha and Nazareth banks. These waves were presumed to originate from the disintegration of a large lee wave formed on the western side of the sill at the time of maximum barotropic flow to the west. In the present paper we focus instead on ISWs propagating in the shallow water above the Saya da Malha (SM) bank (to the north of the sill), rather than on those propagating in deep water (here denominated as type-I or -II waves if propagating to the west or east respectively). Analysis of an extended SAR image dataset reveals strong sea surface signatures of complex patterns of ISWs propagating over the SM bank arising from different sources. We identify three distinct types of waves, and propose suitable generation mechanisms for them using synergy from different remotely sensed datasets, together with analyses of linear phase speeds (resulting from local stratification and bathymetry). In particular, we find a family of ISWs (termed here A-type waves) which results from the disintegration of a lee wave which forms on the western slopes of SM. We also identify two further wave trains (B- and C-type waves) which we suggest result from refraction of the deep water type-I and -II waves onto the SM bank. Therefore, both B- and C-type waves can be considered to result from the same generation source as the type-I and -II waves. Finally, we consider the implications of the ISWs for mixing and biological production over the SM bank, and provide direct evidence, from ocean colour satellite images, of enhanced surface chlorophyll over a shallow topographic feature on the bank, which is
Energy Technology Data Exchange (ETDEWEB)
Nazari-Golshan, A., E-mail: nazarigolshan@yahoo.com [Physics Department, Shahed University, Tehran (Iran, Islamic Republic of)
2016-08-15
Ion-acoustic (IA) solitary wave propagation is investigated by solving the fractional Schamel equation (FSE) in a homogenous system of unmagnetized plasma. This plasma consists of the nonextensive trapped electrons and cold fluid ions. The effects of the nonextensive q-parameter, electron trapping, and fractional parameter have been studied. The FSE is derived by using the semi-inverse and Agrawal's methods. The analytical results show that an increase in the amount of electron trapping and nonextensive q-parameter increases the soliton ion-acoustic amplitude in agreement with the previously obtained results. However, it is vice-versa for the fractional parameter. This feature leads to the fact that the fractional parameter may be used to increase the IA soliton amplitude instead of increasing electron trapping and nonextensive parameters.
International Nuclear Information System (INIS)
EL-Labany, S. K.; Khedr, D. M.; El-Shamy, E. F.; Sabry, R.
2013-01-01
In the present research paper, the effect of bounded nonplanar (cylindrical and spherical) geometry on the interaction between two nonplanar electrostatic solitary waves (NESWs) in electron–positron–ion plasmas has been studied. The extended Poincaré–Lighthill–Kuo method is used to obtain nonplanar phase shifts after the interaction of the two NESWs. This study is a first attempt to investigate nonplanar phase shifts and trajectories for NESWs in a two-fluid plasma (a pair-plasma) consisting of electrons and positrons, as well as immobile background positive ions in nonplanar geometry. The change of phase shifts and trajectories for NESWs due to the effect of cylindrical geometry, spherical geometry, the physical processes (either isothermal or adiabatic), and the positions of two NESWs are discussed. The present investigation may be beneficial to understand the interaction between two NESWs that may occur in active galactic nuclei.
Energy Technology Data Exchange (ETDEWEB)
EL-Labany, S. K.; Khedr, D. M. [Department of Physics, Faculty of Science, Damietta University, Damietta El-Gedida 34517 (Egypt); El-Shamy, E. F. [Department of Physics, Faculty of Science, Damietta University, Damietta El-Gedida 34517 (Egypt); Department of Physics, College of Science, King Khalid University, P.O. 9004, Abha (Saudi Arabia); Sabry, R. [Department of Physics, Faculty of Science, Damietta University, Damietta El-Gedida 34517 (Egypt); Department of Physics, College of Science and Humanitarian Studies, Salman bin Abdulaziz University, Alkharj (Saudi Arabia)
2013-01-15
In the present research paper, the effect of bounded nonplanar (cylindrical and spherical) geometry on the interaction between two nonplanar electrostatic solitary waves (NESWs) in electron-positron-ion plasmas has been studied. The extended Poincare-Lighthill-Kuo method is used to obtain nonplanar phase shifts after the interaction of the two NESWs. This study is a first attempt to investigate nonplanar phase shifts and trajectories for NESWs in a two-fluid plasma (a pair-plasma) consisting of electrons and positrons, as well as immobile background positive ions in nonplanar geometry. The change of phase shifts and trajectories for NESWs due to the effect of cylindrical geometry, spherical geometry, the physical processes (either isothermal or adiabatic), and the positions of two NESWs are discussed. The present investigation may be beneficial to understand the interaction between two NESWs that may occur in active galactic nuclei.
EL-Labany, S. K.; EL-Shamy, E. F.; Sabry, R.; Khedr, D. M.
2013-01-01
In the present research paper, the effect of bounded nonplanar (cylindrical and spherical) geometry on the interaction between two nonplanar electrostatic solitary waves (NESWs) in electron-positron-ion plasmas has been studied. The extended Poincaré-Lighthill-Kuo method is used to obtain nonplanar phase shifts after the interaction of the two NESWs. This study is a first attempt to investigate nonplanar phase shifts and trajectories for NESWs in a two-fluid plasma (a pair-plasma) consisting of electrons and positrons, as well as immobile background positive ions in nonplanar geometry. The change of phase shifts and trajectories for NESWs due to the effect of cylindrical geometry, spherical geometry, the physical processes (either isothermal or adiabatic), and the positions of two NESWs are discussed. The present investigation may be beneficial to understand the interaction between two NESWs that may occur in active galactic nuclei.
Propagation of nonplanar dust-acoustic envelope solitary waves in a two-ion-temperature dusty plasma
International Nuclear Information System (INIS)
Xue Jukui
2004-01-01
The evolution of the cylindrical and spherical dust-acoustic envelope solitary wave (DAESW) in an unmagnetized dusty plasma consisting of negatively charged dust fluid and ions of two different temperatures is investigated. By using the reductive perturbation method, the cylindrical and spherical geometry-modified nonlinear Schroedinger equation (GMNLSE) is obtained. The change of the DAESW amplitude due to the cylindrical and spherical geometry effects is deduced analytically. It is shown that there exist two time ranges. On the other hand, the wave amplitude changes with time τ as (τ 0 /τ) m/2 when the geometry effect is stronger and as (τ 0 /τ) m when the geometry effect is weaker, where τ 0 is the initial time, and m=1 (2) refers to the cylindrical (spherical) case. The theoretical results are verified by the numerical calculation for the GMNLSE. The modulational instability of dust-acoustic waves governed by the GMNLSE is also presented. It is shown that the propagation of the DAESW in cylindrical geometry, spherical geometry, and planar one-dimensional geometry are very different. The presence of a second component of ions would modify the nature of the modulation instabilities
El-Taibany, W. F.
2005-01-01
The nonlinear propagation of electron acoustic waves (EAWs) in a plasma composed of a cold electron fluid, hot electrons obeying trapped/vortex-like distribution, warm electron beam, and stationary ions is considered. The streaming velocity of the beam, uo, plays the dominant role in changing the topology of the linear dispersion relation. For small but finite amplitude EAWs, a modified Korteweg de Vries (MKdV) equation is derived. It is found that the MKdV supports EAWs having a positive potential, which corresponds to a hole (hump) in the cold (hot) electron number density. The energy soliton amplitude decreases, though its width increases for any increase in the beam parameters. In the vicinity of the isothermal population, a nonlinear evolution equation with mixed nonlinearity is obtained. Its solution gives a (compressive/rarefactive) soliton or a compressive double layer (DL) depending on the system parameters. For arbitrary amplitude EAWs, the exact Sagdeev potential has been derived. The admitted Mach number regime widens due to an increase of the beam parameters. With a better approximation in the Sagdeev potential, more features of solitary waves, e.g., spiky and explosive, are also highlighted. The introduced effects modify significantly the wave velocity, the amplitude, and the width of the EAWs investigated numerically. This theoretical model is in good agreement with the broadband noise emission observed by Geotail spacecraft in the plasma sheet boundary layer of the Earth's magnetosphere.
Ahmad, S.; Ahmad, A.; Bacha, B. A.; Khan, A. A.; Abdul Jabar, M. S.
2017-12-01
Surface Plasmon Polaritons (SPPs) are theoretically investigated at the interface of a dielectric metal and gold. The output pulse from the dielectric is used as the input pulse for the generation of SPPs. The SPPs show soliton-like behavior at the interface. The solitary form of a SPP is maintained under the effects of Kerr nonlinearity, Doppler broadening and Fresnel dragging whereas its phase shift is significantly modified. A 0.3radian phase shift is calculated in the presence of both Kerr nonlinearity and Fresnel dragging in the absence of plasma motion. The phase shift is enhanced to 60radian due to the combined effect of Doppler broadening, Kerr nonlinearity and Fresnel dragging. The results may have significant applications in nano-photonics, optical tweezers, photovoltaic devices, plasmonster and sensing technology.
Directory of Open Access Journals (Sweden)
Mostafa M.A. Khater
Full Text Available In this article and for the first time, we introduce and describe Khater method which is a new technique for solving nonlinear partial differential equations (PDEs.. We apply this method for each of the following models Bogoyavlenskii equation, couple Boiti-Leon-Pempinelli system and Time-fractional Cahn-Allen equation. Khater method is very powerful, Effective, felicitous and fabulous method to get exact and solitary wave solution of (PDEs.. Not only just like that but it considers too one of the general methods for solving that kind of equations since it involves some methods as we will see in our discuss of the results. We make a comparison between the results of this new method and another method. Keywords: Bogoyavlenskii equations system, Couple Boiti-Leon-Pempinelli equations system, Time-fractional Cahn-Allen equation, Khater method, Traveling wave solutions, Solitary wave solutions
Quantum ion acoustic solitary waves in electron-ion plasmas: A Sagdeev potential approach
International Nuclear Information System (INIS)
Mahmood, S.; Mushtaq, A.
2008-01-01
Linear and nonlinear ion acoustic waves are studied in unmagnetized electron-ion quantum plasmas. Sagdeev potential approach is employed to describe the nonlinear quantum ion acoustic waves. It is found that density dips structures are formed in the subsonic region in a electron-ion quantum plasma case. The amplitude of the nonlinear structures remains constant and the width is broadened with the increase in the quantization of the system. However, the nonlinear wave amplitude is reduced with the increase in the wave Mach number. The numerical results are also presented
Directory of Open Access Journals (Sweden)
E. M. Dubinin
2006-11-01
Full Text Available One-dimensional stationary flows of a plasma consisting of two ion populations and electrons streaming against a heavy ion cloud are studied. The flow structure is critically governed by the position of sonic and critical points, at which the flow is shocked or choked. The concept of sonic and critical points is suitably generalized to the case of multi-ion plasmas to include a differential ion streaming. For magnetic field free flows, the sonic and critical loci in the (upx, uhx space coincide. Amongst the different flow patterns for the protons and heavy ions, there is a possible configuration composed of a "heavy ion shock" accompanied by a proton rarefaction. The magnetic field introduces a "stiffness" for the differential ion streaming transverse to the magnetic field. In general, both ion fluids respond similarly in the presence of "ion obstacle"; the superfast (subfast flows are decelerated (accelerated. The collective flow is choked when the dynamic trajectory (upx, uhx crosses the critical loci. In specific regimes the flow contains a sequence of solitary structures and as a result, the flow is strongly bunched. In each such substructure the protons are almost completely replaced by the heavies. A differential ion streaming is more accessible in the collective flows oblique to the magnetic field. Such a flexibility of the ion motion is determined by the properties of energy integrals and the Bernoulli energy functions of each ion species. The structure of flows, oblique to the magnetic field, depends critically on the velocity regime and demonstrates a rich variety of solitary and oscillatory nonlinear wave structures. The results of the paper are relevant to the plasma and field environments at comets and planets through the interaction with the solar wind.
Solitary waves for a coupled nonlinear Schrodinger system with dispersion management
Directory of Open Access Journals (Sweden)
Panayotis Panayotaros
2010-08-01
Full Text Available We consider a system of coupled nonlinear Schrodinger equations with periodically varying dispersion coefficient that arises in the context of fiber-optics communication. We use Lions's Concentration Compactness principle to show the existence of standing waves with prescribed L^2 norm in an averaged equation that approximates the coupled system. We also use the Mountain Pass Lemma to prove the existence of standing waves with prescribed frequencies.
Lu, Dianchen; Seadawy, A. R.; Arshad, M.; Wang, Jun
In this paper, new exact solitary wave, soliton and elliptic function solutions are constructed in various forms of three dimensional nonlinear partial differential equations (PDEs) in mathematical physics by utilizing modified extended direct algebraic method. Soliton solutions in different forms such as bell and anti-bell periodic, dark soliton, bright soliton, bright and dark solitary wave in periodic form etc are obtained, which have large applications in different branches of physics and other areas of applied sciences. The obtained solutions are also presented graphically. Furthermore, many other nonlinear evolution equations arising in mathematical physics and engineering can also be solved by this powerful, reliable and capable method. The nonlinear three dimensional extended Zakharov-Kuznetsov dynamica equation and (3 + 1)-dimensional modified KdV-Zakharov-Kuznetsov equation are selected to show the reliability and effectiveness of the current method.
El-Labany, S. K.; El-Shamy, E. F.; Sabry, R.; Shokry, M.
2010-02-01
In the present paper, the characteristics of the head-on collision between two dust-acoustic solitary waves (DASWs) in an adiabatic dusty plasma consisting of variable negatively charged dust grains, isothermal electrons and two-temperature isothermal ions in the presence of an external oblique magnetic field are investigated. Using the extended Poincaré-Lighthill-Kuo (PLK) method, the Korteweg-de Vries (KdV) equations and the analytical phase shifts after the head-on collision of two solitary waves are derived. The effects of the magnetic field and its obliqueness, two different type of isothermal ions and the dust particles adiabaticity are discussed. It is found that these factors significantly affect the phase shifts.
Directory of Open Access Journals (Sweden)
Dianchen Lu
Full Text Available In this paper, new exact solitary wave, soliton and elliptic function solutions are constructed in various forms of three dimensional nonlinear partial differential equations (PDEs in mathematical physics by utilizing modified extended direct algebraic method. Soliton solutions in different forms such as bell and anti-bell periodic, dark soliton, bright soliton, bright and dark solitary wave in periodic form etc are obtained, which have large applications in different branches of physics and other areas of applied sciences. The obtained solutions are also presented graphically. Furthermore, many other nonlinear evolution equations arising in mathematical physics and engineering can also be solved by this powerful, reliable and capable method. The nonlinear three dimensional extended Zakharov-Kuznetsov dynamica equation and (3 + 1-dimensional modified KdV-Zakharov-Kuznetsov equation are selected to show the reliability and effectiveness of the current method. Keywords: Modified extended direct algebraic method, Solitons, Solitary wave solutions, Jacobi and Weierstrass elliptic function solutions, Three dimensional extended Zakharov-Kuznetsov dynamical equation, (3 + 1-Dim modified KdV-Zakharov-Kuznetsov equation
Dust-acoustic solitary waves in a dusty plasma with two-temperature ...
Indian Academy of Sciences (India)
acoustic waves in a dusty plasma (containing a negatively charged dust ﬂuid, Boltzmann distributed electrons and two-temperature nonthermal ions) is investigated. The effects of two-temperature nonthermal ions on the basic properties of small but ...
Solitary heat waves in nonlinear lattices with squared on-site potential
Indian Academy of Sciences (India)
Abstract. A model Hamiltonian is proposed for heat conduction in a nonlinear lattice with squared on-site potential using the second quantized operators and averaging the same using a suitable wave function, equations are derived in discrete form for the field amplitude and the prop- erties of heat transfer are examined ...
Flow and Turbulence at Rubble-Mound Breakwater Armor Layers under Solitary Wave
DEFF Research Database (Denmark)
Jensen, Bjarne; Christensen, Erik Damgaard; Sumer, B. Mutlu
2015-01-01
This paper presents the results of an experimental investigation of the flow and turbulence at the armor layer of rubble-mound breakwaters during wave action. The study focused on the details of the flow and turbulence in the armor layer and on the effect of the porous core on flow and stability....
Dust-acoustic solitary waves in a dusty plasma with two-temperature ...
Indian Academy of Sciences (India)
Abstract. By using reductive perturbation method, the nonlinear propagation of dust-acoustic waves in a dusty plasma (containing a negatively charged dust fluid, Boltzmann distributed electrons and two-temperature nonthermal ions) is investigated. The effects of two-temperature nonthermal ions on the basic properties of ...
Solitary waves, steepening and initial collapse in the Maxwell-Lorentz system
DEFF Research Database (Denmark)
Sørensen, Mads Peter; Brio, Moysey; Webb, Garry
2002-01-01
We present a numerical study of Maxwell's equations in nonlinear dispersive optical media describing propagation of pulses in one Cartesian space dimension. Dispersion and nonlinearity are accounted for by a linear Lorentz model and an instantaneous Kerr nonlinearity, respectively. The dispersion......–Rosales weakly dispersive system. The weak dispersion in general cannot prevent the wave breaking with instantaneous or delayed nonlinearities....
Mamun, A. A.
2018-02-01
A general (but realistic) self-gravitating degenerate quantum plasma system (SG-DQPS) containing inertialess degenerate electron species, inertial degenerate light, and heavy ion/nucleus species is considered to examine the possibility for the existence of degenerate pressure driven self-gravito-acoustic (DPD-SGA) solitary waves (SWs) formed in such a SG-DQPS. The pseudo-potential approach, which is valid for the arbitrary amplitude DPD-SGA SWs, is employed. It is found that depending on the value of the number density of heavy ion/nucleus species, the SG-DQPS under consideration supports the existence of positive or the coexistence of positive and negative DPD-SGA SWs. The basic features (polarity, amplitude, and width) of both positive and negative DPD-SGA SWs are found to be significantly modified by the dynamics of heavy ion/nucleus species. The theoretical investigation presented here is so general that it can be applied not only in astrophysical SG-DQPSs (such as white dwarf and neutron star SG-DQPSs), but also in laboratory SG-DQPSs (viz., solid density and laser-produced SG-DQPSs) to identify the salient features of the DPD-SGA SWs formed in them.
Tang, Qunshu; Hobbs, Richard; Zheng, Chan; Biescas, Berta; Caiado, Camila
2016-06-01
Marine seismic reflection technique is used to observe the strong ocean dynamic process of nonlinear internal solitary waves (ISWs or solitons) in the near-surface water. Analysis of ISWs is problematical because of their transient nature and limitations of classical physical oceanography methods. This work explores a Markov Chain Monte Carlo (MCMC) approach to recover the temperature and salinity of ISW field using the seismic reflectivity data and in situ hydrographic data. The MCMC approach is designed to directly sample the posterior probability distributions of temperature and salinity which are the solutions of the system under investigation. The principle improvement is the capability of incorporating uncertainties in observations and prior models which then provide quantified uncertainties in the output model parameters. We tested the MCMC approach on two acoustic reflectivity data sets one synthesized from a CTD cast and the other derived from multichannel seismic reflections. This method finds the solutions faithfully within the significantly narrowed confidence intervals from the provided priors. Combined with a low frequency initial model interpreted from seismic horizons of ISWs, the MCMC method is used to compute the finescale temperature, salinity, acoustic velocity, and density of ISW field. The statistically derived results are equivalent to the conventional linearized inversion method. However, the former provides us the quantified uncertainties of the temperature and salinity along the whole section whilst the latter does not. These results are the first time ISWs have been mapped with sufficient detail for further analysis of their dynamic properties.
Bojanic, Nebojsa; Bumbasirevic, Uros; Vukovic, Ivan; Bojanic, Gordana; Milojevic, Bogomir; Nale, Djordje; Durutovic, Otas; Djordjevic, Dejan; Nikic, Predrag; Vuksanovic, Aleksandar; Tulic, Cane; Micic, Sava
2015-02-01
To assess the oncologic and functional outcomes of testicular sparing surgery (TSS) based on a single institution experience. Forty-one patients with bilateral and 3 patients with solitary testicle tumors were referred to our institution. The inclusion criteria for TSS were normal serum testosterone levels, and tumor size (<2 cm). Sperm analysis and hormone status evaluation were performed preoperatively and postoperatively. None of the patients underwent local radiation therapy following TSS for reasons of fertility preservation. A total of 26 TSS were performed in 24 patients. The median follow-up period was 51.0 months. Seven patients developed local recurrence, of which 5 had TIN and were subjected to radical orchiectomy, whereas re-do TSS was done in remaining 2 patients. The overall survival of the study group was 100%, and the presence of testicular intraepithelial neoplasia (TIN) was associated with worse recurrence-free survival (P=0.031, log-rank). Testosterone values were normal in all of the patients, while 4 patients achieved conception. TSS is acceptable from an oncological point of view, and it enables continuation of a patient's life without lifelong hormonal substitution. Additionally, local irradiation therapy could be delayed in patients with TIN who wish to father children, but with high local recurrence rate. © 2014 Wiley Periodicals, Inc.
Periodic folded waves for a (2+1)-dimensional modified dispersive water wave equation
International Nuclear Information System (INIS)
Wen-Hua, Huang
2009-01-01
A general solution, including three arbitrary functions, is obtained for a (2+1)-dimensional modified dispersive water-wave (MDWW) equation by means of the WTC truncation method. Introducing proper multiple valued functions and Jacobi elliptic functions in the seed solution, special types of periodic folded waves are derived. In the long wave limit these periodic folded wave patterns may degenerate into single localized folded solitary wave excitations. The interactions of the periodic folded waves and the degenerated single folded solitary waves are investigated graphically and found to be completely elastic. (general)
Energy Technology Data Exchange (ETDEWEB)
Mayout, Saliha; Gougam, Leila Ait [Faculty of Physics, Theoretical Physics Laboratory, Plasma Physics Group, University of Bab-Ezzouar, USTHB, B.P. 32, El Alia, Algiers 16111 (Algeria); Tribeche, Mouloud, E-mail: mouloudtribeche@yahoo.fr, E-mail: mtribeche@usthb.dz [Faculty of Physics, Theoretical Physics Laboratory, Plasma Physics Group, University of Bab-Ezzouar, USTHB, B.P. 32, El Alia, Algiers 16111 (Algeria); Algerian Academy of Sciences and Technologies, Algiers (Algeria)
2016-03-15
The combined effects of ionization, ion loss, and electron suprathermality on dust ion-acoustic solitary waves in a collisional dusty plasma are examined. Carrying out a small but finite amplitude analysis, a damped Korteweg-de Vries (dK–dV) equation is derived. The damping term decreases with the increase of the spectral index and saturates for Maxwellian electrons. Choosing typical plasma parameters, the analytical approximate solution of the dK-dV equation is numerically analyzed. We first neglect the ionization and ion loss effects and account only for collisions to estimate the relative importance between these damping terms which can act concurrently. Interestingly, we found that as the suprathermal character of the electrons becomes important, the strength of the collisions related dissipation becomes more important and causes the dust ion-acoustic solitary wave amplitude to decay more rapidly. Moreover, the collisional damping may largely prevail over the ionization and ion loss related damping. The latter becomes more effective as the electrons evolve far away from their thermal equilibrium. Our results complement and provide new insights into previously published work on this problem.
Nonlinear ion-acoustic solitary waves with warm ions and non-Maxwellian electrons in space plasmas
Hussain Shah, Khalid; Qureshi, Nouman
2017-04-01
Electrons velocity distributions are often observed with non-Maxwellian features such flat tops at low energies and/or superthermal tails at high energies from different regions of near Earth plasmas such as Earth's bow shock, auroral zone and magnetosphere by numerous satellites. Such non-Maxwellian distributions are well modelled by generalized (r,q) distribution or Cairns distribution. Solitons are nonlinear solitary structures and are integral part of space plasmas. In this paper, we present a fluid model containing Cairns (r,q) distributed non-Maxwellian electrons and derive the Sagdeev potential for fully nonlinear fluid equations. We found that compressive solitons can be developed in such a plasma. The results from our model can be used to interpret solitary structures in space plasmas when electrons are obeying the non-Maxwellian flat tops along with the high energy tails.
Directory of Open Access Journals (Sweden)
Mearini E
2014-05-01
Full Text Available Ettore Mearini,1 Giovanni Cochetti,1 Francesco Barillaro,1 Sonia Fatigoni,2 Fausto Roila2 1Department of Medical-Surgical Specialties and Public Health, Division of Urological Andrological Surgery and Minimally Invasive Techniques, University of Perugia, Terni, Italy; 2Medical Oncology, S Maria Hospital, Terni, Italy Abstract: Solitary fibrous tumors are rare mesenchymal spindle cell neoplasms that are usually found in the pleura. The kidneys are an uncommon site and only few cases of renal solitary fibrous tumor exhibit malignant behavior metastasizing to the liver, lung, and bone through the hematogenous pathway. Purpose: To describe the first case of lymph node metastasis from renal solitary fibrous tumor in order to increase the knowledge about the malignant behavior of these tumors. Patients and methods: A 19-year-old female patient had intermittent hematuria for several months without flank pain or other symptoms. A chest and abdomen CT scan was performed and showed a multi-lobed bulky solid mass of 170 × 98 × 120 mm in the left kidney. One day before the surgery, the left renal artery was catheterized and the kidney embolization was performed using a Haemostatic Absorbable Gelatin Sponge and polyvinyl alcohol. We then performed a radical nephrectomy with hilar, para-aortic, and inter-aortocaval lymphadenectomy. Results: Estimated intraoperative blood loss was 200 mL and the operative time was 100 minutes. No postoperative complications occurred. The hospital stay was 7 days long. The histological examination was malignant solitary fibrous tumor of the kidney. Cancerous tissue showed cellular atypia, with an increased mitotic index (up to 7 × 10 hpf. Immunohistochemical analysis showed positive results for CD34, BCL2, partial expression of HBME1, and occasionally of synaptophysin. Histological evaluation confirmed the presence of metastasis in one hilar node. The patient did not receive any other therapy. At 30-month follow-up, the
Lung cancer - solitary nodule; Infectious granuloma - pulmonary nodule; SPN ... More than half of all solitary pulmonary nodules are noncancerous ... infections. Infectious granulomas (which are formed by cells as ...
International Nuclear Information System (INIS)
Kevrekidis, P.G.; Herring, G.J.; Lafortune, S.; Hoq, Q.E.
2012-01-01
We propose a consideration of the properties of the two-dimensional Ablowitz–Ladik discretization of the ubiquitous nonlinear Schrödinger (NLS) model. We use singularity confinement techniques to suggest that the relevant discretization should not be integrable. More importantly, we identify the prototypical solitary waves of the model and examine their stability, illustrating the remarkable feature that near the continuum limit, this discretization leads to the absence of collapse and complete spectral wave stability, in stark contrast to the standard discretization of the NLS. We also briefly touch upon the three-dimensional case and generalizations of our considerations therein, and also present some more exotic solutions of the model, such as exact line solitons and discrete vortices. -- Highlights: ► The two-dimensional version of the Ablowitz–Ladik discretization of the nonlinear Schrödinger (NLS) equation is considered. ► It is found that near the continuum limit the fundamental discrete soliton is spectrally stable. ► This finding is in sharp contrast with the case of the standard discretization of the NLS equation. ► In the three-dimensional version of the model, the fundamental solitons are unstable. ► Additional waveforms such as exact unstable line solitons and discrete vortices are also touched upon.
International Nuclear Information System (INIS)
Fan, G.; Sun, B.; Wu, Z.; Guo, Q.; Guo, Y.
2004-01-01
AIM: To determine whether single-voxel proton magnetic resonance spectroscopy (1HMRS) could be used to differentiate gliomas from metastases on the basis of differences in metabolite levels in the different involved regions. MATERIALS AND METHODS: Twenty-two patients (age range from 32 to 62 years, with a median age of 46.7 years) with a solitary brain tumour (14 gliomas, eight metastases) underwent conventional, gadolinium-DTPA enhanced T1-weighted images, and 1HMRS before surgical resection. Spectra from the enhancing tumour, the peritumoural region, and normal brain were obtained from 1HMRS. A point resolved spectroscopy sequence was required for 1HMRS. The metabolites in the spectra include: N-acetylaspartate (NAA), choline (CHO), creatine compounds (CR), myo-inositol (MI), lactate (LAC), glutamate and glutamine (Glu-n). Relative concentrations of metabolites were related to the peak area, and expressed with reference to CR. Student's t-test was used to determine whether there was a statistically significant difference in relative metabolic ratios between high-grade gliomas and metastases. Meanwhile, 16 of all 22 patients were re-examined using magnetic resonance imaging (MRI) within 6 months of surgical resection. Recurrence was present in three patients (two gliomas, one metastasis). RESULTS: Of the 14 patients with gliomas, the peaks of NAA were reduced in three cases; the peaks of LAC, which were elevated, appeared as typical double-peaks in the peritumoural region in nine cases; the peaks of Glu-n, which were also elevated, had a zigzag appearance in seven cases. The peaks of MI were increased in the tumoural region in eight cases, and CHO levels were elevated in all 14 cases. Of the eight patients with metastases, Glu-n peaks in the tumoural region in three cases and CHO peaks in the tumoural region in four cases were elevated, respectively, while the peaks of CR were reduced in three cases, and the peaks of NAA were markedly reduced in four cases within
Classification of single travelling wave solutions to the generalized ...
Indian Academy of Sciences (India)
c Indian Academy of Sciences. Vol. 80, No. 5. — journal of. May 2013 physics pp. 771–783. Classification of single travelling wave solutions to the generalized Zakharov–Kuznetsov equation ... linear ion-acoustic waves in a strongly magnetized lossless plasma composed of cold ions and hot isothermal electrons [10].
The classification of the single travelling wave solutions to the ...
Indian Academy of Sciences (India)
The discrimination system for the polynomial method is applied to variant Boussinesq equations to classify single travelling wave solutions. In particular, we construct corresponding solutions to the concrete parameters to show that each solution in the classification can be realized.
Oblique propagation of dust ion-acoustic solitary waves in a magnetized dusty pair-ion plasma
Energy Technology Data Exchange (ETDEWEB)
Misra, A. P., E-mail: apmisra@visva-bharati.ac.in, E-mail: apmisra@gmail.com; Barman, Arnab [Department of Mathematics, Siksha Bhavana, Visva-Bharati University, Santiniketan-731 235, West Bengal (India)
2014-07-15
We investigate the propagation characteristics of electrostatic waves in a magnetized pair-ion plasma with immobile charged dusts. It is shown that obliquely propagating (OP) low-frequency (in comparison with the negative-ion cyclotron frequency) long-wavelength “slow” and “fast” modes can propagate, respectively, as dust ion-acoustic (DIA) and dust ion-cyclotron (DIC)-like waves. The properties of these modes are studied with the effects of obliqueness of propagation (θ), the static magnetic field, the ratios of the negative to positive ion masses (m), and temperatures (T) as well as the dust to negative-ion number density ratio (δ). Using the standard reductive perturbation technique, we derive a Korteweg-de Vries (KdV) equation which governs the evolution of small-amplitude OP DIA waves. It is found that the KdV equation admits only rarefactive solitons in plasmas with m well below its critical value m{sub c} (≫ 1) which typically depends on T and δ. It is shown that the nonlinear coefficient of the KdV equation vanishes at m = m{sub c}, i.e., for plasmas with much heavier negative ions, and the evolution of the DIA waves is then described by a modified KdV (mKdV) equation. The latter is shown to have only compressive soliton solution. The properties of both the KdV and mKdV solitons are studied with the system parameters as above, and possible applications of our results to laboratory and space plasmas are briefly discussed.
Stochastic acceleration by a single wave in a magnetized plasma
Energy Technology Data Exchange (ETDEWEB)
Smith, R.
1977-09-22
A particularly simple problem exhibiting stochasticity is the motion of a charged particle in a uniform magnetic field and a single wave. Detailed studies of this wave-particle interaction show the following features. An electrostatic wave propagating obliquely to the magnetic field causes stochastic motion if the wave amplitude exceeds a certain threshold. The overlap of cyclotron resonances then destroys a constant of the motion, allowing strong particle acceleration. A wave of large enough amplitude would thus suffer severe damping and lead to rapid heating of a particle distribution. The stochastic motion resembles a diffusion process even though the wave spectrum contains only a single wave. The motion of ions in a nonuniform magnetic field and a single electrostatic wave is treated in our study of a possible saturation mechanism of the dissipative trapped-ion instability in a tokamak. A theory involving the overlap of bounce resonances predicts the main features found in the numerical integration of the equations of motion. Ions in a layer near the trapped-circulating boundary move stochastically. This motion leads to nonlinear stabilization mechanisms which are described qualitatively.
Periodic Folded Wave Patterns for (2+1)-Dimensional Higher-Order Broer-Kaup Equation
International Nuclear Information System (INIS)
Huang Wenhua
2008-01-01
A general solution including three arbitrary functions is obtained for the (2+1)-dimensional higher-order Broer-Kaup equation by means of WTC truncation method. Introducing proper multiple valued functions and Jacobi elliptic functions in the seed solution, special types of periodic folded waves are derived. In long wave limit these periodic folded wave patterns may degenerate into single localized folded solitary wave excitations. The interactions of the periodic folded waves and their degenerated single folded solitary waves are investigated graphically and are found to be completely elastic
Energy Technology Data Exchange (ETDEWEB)
DuBois, D. F. (Donald F.); Yin, L. (Lin); Daughton, W. S. (William S.); Bezzerides, B. (Bandel); Dodd, E. S. (Evan S.); Vu, H. X. (Hoanh X.)
2004-01-01
Detailed diagnostics of quasi-2D RPIC simulations of backward stimulated Raman scattering (BSRS), from single speckles under putative NIF conditions, reveal a complex spatio-temporal behavior. The scattered light consists of localized packets, tens of microns in width, traveling toward the laser at an appreciable fraction of the speed of light. Sub pico-second reflectivity pulses occur as these packets leave the system. The LW activity consists of a front traveling with the light packets with a wake of free LWs traveling in the laser direction. The parametric coupling occurs in the front where the scattered light and LW overlap and are strongest. As the light leaves the plasma the LW quickly decays, liberating its trapped electrons. The high frequency part of the |n{sub e}(k,{omega})|{sup 2} spectrum, where n{sub e} is the electron density fluctuation, consists of a narrow streak or straight line with a slope that is the velocity of the parametric front. The time dependence of |n{sub e}(k,t)|{sup 2}, shows that during each pulse the most intense value of k also 'chirps' to higher values, consistent with the k excursions seen in the |n{sub e}(k,{omega})|{sup 2} spectrum. But k does not always return, in the subsequent pulses, to the original parametrically matched value, indicating that, in spite of side loss, the electron distribution function does not return to its original Maxwellian form. Liberated pulses of hot electrons result in down-stream, bump on tail distributions that excite LWs and beam acoustic modes deeper in the plasma. The frequency broadened spectra are consistent with Thomson scatter spectra observed in TRIDENT single-hot-spot experiments in the high k{lambda}{sub D}, trapping regime. Further details including a comparison of results from full PIC simulations, and movies of the spatio-temporal behavior, will be given in the poster by L Yin et al.
Dual traveling wave rotary ultrasonic motor with single active vibrator
An, Dawei; Yang, Ming; Zhuang, Xiaoqi; Yang, Tianyue; Meng, Fan; Dong, Zhaopeng
2017-04-01
Traveling wave rotary ultrasonic motor with double vibrators can improve the output performance effectively. However, the rotor has to be energized through a slip ring, which increases the complexity and reduces the reliability. Inheriting the concept of two traveling waves propagating in the stator and rotor, a dual traveling wave rotary ultrasonic motor energized only in the stator is proposed. By analyzing the oscillatory differential equation and the contact particles motion, a traveling wave is found in the rotor and the drive mechanism of dual traveling wave is studied. With the resonant rotor adopted, the consistent eigenfrequencies are calculated by finite element method and verified by an impedance analyzer. The performance experiment presents that the dual traveling wave rotary ultrasonic motor is superior to the motor with single traveling wave. The no-load speed is 60 rpm and the stalling torque is 0.85 Nm. Additionally, compared with a reported motor with double vibrators, the proposed motor presents the better output performance and the simpler design.
The classification of the single travelling wave solutions to the ...
Indian Academy of Sciences (India)
Exact solution; single travelling wave solution; complete discrimination system for the polynomial; the generalized PC ... Recently, a method named as the complete discrimination system for polynomial method has been proposed by Liu [11–16]. ...... to the generalized PC equation. By integrating and taking some trans-.
The classification of the single travelling wave solutions to the ...
Indian Academy of Sciences (India)
2016-09-21
Sep 21, 2016 ... The discrimination system for the polynomial method is applied to variant Boussinesq equations to classify single travelling wave solutions. In particular, we construct corresponding solutions to the concrete parameters to show that each solution in the classification can be realized. Keywords. Exact solution ...
The classification of the single travelling wave solutions to the ...
Indian Academy of Sciences (India)
The classification of the single travelling wave solutions to the generalized Pochhammer–Chree equation. HUI-LING FAN. ∗ and XIN LI. School of Science, Heilongjiang Bayi Agriculture University, Daqing 163319, China. ∗. Corresponding author. E-mail: huilingnepu@126.com. MS received 11 June 2013; revised 2 ...
The classification of single travelling wave solutions to the Camassa ...
Indian Academy of Sciences (India)
Introduction. Classifications of single travelling wave solutions to some nonlinear differential equations have been obtained extensively by the complete discrimination system for polynomial method proposed by Liu [1–7]. Furthermore, Wang and Li [8] used Liu's method and factorization method proposed by Cornejo-Pérez ...
International Nuclear Information System (INIS)
Wolpers, C.; Wosiewitz, U.
1986-01-01
Solitary pigment stones of the gall-bladder are rare (1.7%). 82,5% are radiopaque, 17.5% radiolucent. 64,8% of radiopaque solitary pigment stones have the structure of a cockade. Such cockades take years to develop. Solitary cholesterol stones with a nucleus of a radiopaque pigment stone should not be treated for litholysis. 8% of solitary cholesterol stones with a cross diameter below 15 mm. possess a radiolucent pigment stone nucleus. X-ray diagnosis for selecting litholytic treatment remains the safest method, especially if the radiologist compares his films regularly with the specimens after surgery. (orig.) [de
Possibility designing half-wave and full-wave molecular rectifiers by using single benzene molecule
Abbas, Mohammed A.; Hanoon, Falah H.; Al-Badry, Lafy F.
2018-02-01
This work focused on possibility designing half-wave and full-wave molecular rectifiers by using single and two benzene rings, respectively. The benzene rings were threaded by a magnetic flux that changes over time. The quantum interference effect was considered as the basic idea in the rectification action, the para and meta configurations were investigated. All the calculations are performed by using steady-state theoretical model, which is based on the time-dependent Hamiltonian model. The electrical conductance and the electric current are considered as DC output signals of half-wave and full-wave molecular rectifiers. The finding in this work opens up the exciting potential to use these molecular rectifiers in molecular electronics.
DEFF Research Database (Denmark)
Henriksen, Casper Christian I
organic fields than in those bordering conventional fields. This was due to the absence of herbicides and to practices inherent to organic farming systems, such as use of clover (a high value bee plant) as a green manure and fodder crop. Solitary bees responded with significantly higher numbers......Summary: The effects of farming system, flower resources and semi-natural habitats on bumblebees and solitary bees in intensively cultivated landscapes in Denmark were investigated in two sets of studies, in 2011 and 2012. The pan trap colour preferences of bumblebees and solitary bees were also...... use as a proxy at four different scales (250, 500, 750 and 1000 m). In 2012, the effect of a four-fold larger area of organic arable fields in simple, homogeneous landscapes on bumblebees and solitary bees was investigated in eight circular landscapes (radius 1000 m). Bumblebees and solitary bees were...
DEFF Research Database (Denmark)
Henriksen, Casper Christian I
Summary: The effects of farming system, flower resources and semi-natural habitats on bumblebees and solitary bees in intensively cultivated landscapes in Denmark were investigated in two sets of studies, in 2011 and 2012. The pan trap colour preferences of bumblebees and solitary bees were also...... assessed. In 2011, bumblebees and solitary bees were trapped in road verges bordering 14 organic (organic sites) and 14 conventional (conventional sites) winter wheat fields. The quantity and quality of local flower resources in the road verge and adjacent field headland were estimated as overall density...... use as a proxy at four different scales (250, 500, 750 and 1000 m). In 2012, the effect of a four-fold larger area of organic arable fields in simple, homogeneous landscapes on bumblebees and solitary bees was investigated in eight circular landscapes (radius 1000 m). Bumblebees and solitary bees were...
Directory of Open Access Journals (Sweden)
LI Jing
2016-07-01
Full Text Available Objective To investigate the value of contrast-enhanced ultrasound (CEUS in the differential diagnosis of single metastatic hepatic carcinoma (MHC and solitary necrotic nodule of the liver (SNNL. MethodsA retrospective analysis was performed for 12 patients with single MHC and 16 patients with SNNL who showed circular enhancement in arterial phase on CEUS. Age, size of lesion, and findings of two-dimensional gray-scale ultrasound and CEUS were compared between the two groups. The two-independent-samples t-test was used for comparison between groups, and the paired t-test was used for comparison within each group. ResultsThe MHC group had a significantly higher mean age than the SNNL group (60.2±11.3 years vs 41.0±9.1 years, t=4.970, P＜0.001. The mean diameter of lesion was 2.86±1.22 cm in the MHC group and 2.97±0.96 cm in the SNNL group, and showed no significant difference between the two groups (t=-0.269, P=0.790. In the MHC group, the lesions had complex and uneven echoes and blurred boundaries, while in the SNNL group, most lesions were in the right lobe and were hypoechoic with clear boundaries. No blood flow signals were detected on CDFI in these two groups. Both groups had circular enhancement around the lesions in arterial phase on CEUS, and the mean thickness showed a significant difference between the MHC group and the SNNL group (5.00±1.69 mm vs 2.37±0.87 mm, t=5.374, P＜0001. In the MHC group, the area in lesions without enhancement in delayed phase was significantly larger than that in arterial phase (t=-4.508, P=0001, while in the SNNL group, the area in lesions without enhancement showed no significant difference between delayed phase and arterial phase (t=-0.449, P=0.660. ConclusionThe thickness of circular enhancement in arterial phase on CEUS and the presence or absence of the enlargement in the area without enhancement contributes to the differential diagnosis of single MHC and SNNL.
Solitary odontodysplasia: A rare entity
Directory of Open Access Journals (Sweden)
D Gurunathan
2011-01-01
Full Text Available Odontodysplasia is a rare, non-hereditary developmental anomaly affecting dental tissues derived from both the mesoderm and ectoderm which results in a bizarre clinical and radiographic appearance. Regional odontodysplasia describes the segmental and localized nature of the condition. Odontodysplasia occurring in a single tooth is a rare occurrence. A case of Solitary odontodysplasia in an eleven year and half old male whose chief complaint was the absence of eruption of permanent maxillary right central incisor teeth is presented. Clinical, radiographic and histological findings of a single tooth, odontodysplasia are described in this case report.
Optical precursors from classical waves to single photons
Chen, JF; Loy, MMT; Du, Shengwang
2013-01-01
Ever since Einstein’s special relativity in 1905, the principle of invariant light speed in vacuum has been attracting attention from a wide range of disciplines. How to interpret the principle of light speed? Is light referred to continuous light, or light pulse with definite boundaries? Recent discovery of superluminal medium triggered vigorous discussion within the Physics community. Can communication via such “superluminal channel” break the speed limit and thus violate causality principle? Or, will a single photon, which is not governed by classical laws of Physics, tend to break the speed limit? To solve these problems, in this Brief we bring in optical precursor, the theoretical works for which started as early as 1914. This is a typical optical phenomenon combining wave propagation theory and light-wave interaction. Both theory and experimental works are covered in this Brief. The study of precursor verifies that the effective information carried by light pulses can never exceed the speed of lig...
The effect of transitional particles driven by single wave
International Nuclear Information System (INIS)
Qiu Yunqing; Xia Mengfen
1987-05-01
The unperturbed separatrix crossing driven by a single wave in a tokamak plasma is discussed. The separatrix crossing is followed by a mixing process, and a small-scale structure occurs in the distribution function in h-ψ plane. The separatrix crossing is a convective process in h-ψ plane, and there is a definite crossing channel. The convective flux and the net flux in h-direction are calculated. The separatrix crossing is accompanied by a radial flux, which is composed of a directional flux and a diffusion flux. (author). 7 refs, 6 figs
Arshad, M.; Seadawy, Aly R.; Lu, Dianchen
2017-08-01
The higher-order nonlinear Schrödinger equation (NLSE) with fourth-order dispersion, cubic-quintic terms, self-steepening and nonlinear dispersive terms describes the propagation of extremely short pulses in optical fibers. In this paper, the elliptic function, bright and dark solitons and solitary wave solutions of higher-order NLSE are constructed by employing a modified extended direct algebraic method, which has important applications in applied mathematics and physics. Furthermore, we also present the formation conditions of the bright and dark solitons for this equation. The modulation instability is utilized to discuss the stability of these solutions, which shows that all solutions are exact and stable. Many other higher-order nonlinear evolution equations arising in applied sciences can also be solved by this powerful, effective and reliable method.
Localizing gravitational wave sources with single-baseline atom interferometers
Graham, Peter W.; Jung, Sunghoon
2018-02-01
Localizing sources on the sky is crucial for realizing the full potential of gravitational waves for astronomy, astrophysics, and cosmology. We show that the midfrequency band, roughly 0.03 to 10 Hz, has significant potential for angular localization. The angular location is measured through the changing Doppler shift as the detector orbits the Sun. This band maximizes the effect since these are the highest frequencies in which sources live for several months. Atom interferometer detectors can observe in the midfrequency band, and even with just a single baseline they can exploit this effect for sensitive angular localization. The single-baseline orbits around the Earth and the Sun, causing it to reorient and change position significantly during the lifetime of the source, and making it similar to having multiple baselines/detectors. For example, atomic detectors could predict the location of upcoming black hole or neutron star merger events with sufficient accuracy to allow optical and other electromagnetic telescopes to observe these events simultaneously. Thus, midband atomic detectors are complementary to other gravitational wave detectors and will help complete the observation of a broad range of the gravitational spectrum.
Bai, Yunjin; Wang, Xiaoming; Yang, Yubo; Han, Ping; Wang, Jia
2017-01-18
To compare the treatment outcomes between percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS) for the management of stones larger than 2 cm in patients with solitary kidney. One hundred sixteen patients with a solitary kidney who underwent RIRS (n = 56) or PCNL (n = 60) for large renal stones (>2 cm) between Jan 2010 and Nov 2015 have been considered. The patients' characteristics, stone characteristics, operative time, incidence of complications, hospital stay, and stone-free rates (SFR) have been evaluated. SFRs after one session were 19.6% and 35.7% for RIRS and PCNL respectively (p = 0.047), but the SFR at 3 months follow-up comparable in both groups (82.1% vs. 88.3%, p = 0.346). The calculated mean operative time for RIRS was longer (p stone clearance can be achieved with multi-session RIRS in the treatment of renal stones larger than 2 cm in patients with solitary kidney. RIRS can be considered as an alternative to PCNL in selected cases.
De Sio, Marco; Autorino, Riccardo; Quarto, Giuseppe; Mordente, Salvatore; Giugliano, Francesco; Di Giacomo, Ferdinando; Neri, Fabio; Quattrone, Carmelo; Sorrentino, Domenico; De Domenico, Renato; D'Armiento, Massimo
2007-11-01
To assess the efficacy and safety of a transportable extracorporeal shock wave lithotripsy (ESWL) machine, the Modulith SLX-F2(TM) (Storz Medical Italia, Rome, Italy), in the management of solitary urinary calculi. The study included 233 patients (mean age 51 years; 172 male, 61 female) with symptomatic solitary renal (group A, 170, mean diameter 15.5 mm) or ureteric stones (group B, 63, mean diameter 9.5 mm) treated in a tertiary care institution. Exclusion criteria for the analysis were: pelvi-ureteric junction obstruction, multiple stones, stone diameter >2 cm, stones in a lower calyx with unfavourable anatomy, active infection, or impacted ureteric stones. Selected patients had ureteric stenting before treatment, and all patients were treated with no anaesthesia. Hospitalization, complications and subsequent auxiliary procedures were evaluated. Patients were assessed after a single ESWL session and after 3 months by a plain abdominal film and renal ultrasonography. Stone-free status was defined as no evidence of calculi, and clinical success as the presence of stone fragments of 1 cm were statistically significant (P < 0.05). Most patients reported that pain during ESWL was mild to moderate and easily tolerated. Only minor complications occurred, with an overall complication rate of 3.8%. This transportable lithotripter is a safe and effective device for managing solitary stones throughout the urinary tract. Its main advantage is represented by the dual-focus system. Moreover, it shares with other contemporary machines several important features such as outpatient setting, no need for anaesthesia, easy patient positioning, and the capability of ancillary procedures.
Kunovský, Lumír; Dastych, Milan; Kroupa, Radek; Hemmelova, Beata; Muckova, Katarina; Chovancova, Miroslava; Kucerova, Lenka; Dolina, Jiri
Gastric antral vascular ectasia (GAVE) and solitary rectal ulcer syndrome (SRUS) are both mentioned in the literature as rare causes of iron deficiency anemia and gastrointestinal (GI) bleeding. GAVE accounts for up to 4 % of upper non-variceal GI bleeding; SRUS is a rare benign disorder that presents with rectal bleeding. We present the case of a 75-year-old patient who was admitted to our facility with anemia. In the same patient, we encountered chronic bleeding from GAVE and SRUS. Both diagnoses were treated endoscopically: GAVE by argon plasma coagulation and a subsequent treatment with proton pump inhibitors and SRUS by adrenaline injection and clipping, consecutively treated with mesalazine enemas. The patient was successfully cured, resulting in a stable level of hemoglobin and no recurrent GI bleeding. We report a unique case of chronic GI bleeding caused by two uncommon diagnoses. The co-occurrence of GAVE and SRUS has not been previously described or published.Key words: anemia - endoscopy - gastric antral vascular ectasia (GAVE) - gastrointestinal bleeding - solitary rectal ulcer syndrome (SRUS).
Is percutaneous nephrolithotomy in solitary kidneys safe?
Wong, Kathie Alexina; Sahai, Arun; Patel, Amit; Thomas, Kay; Bultitude, Matthew; Glass, Jonathan
2013-11-01
To review our experience from a high volume stone center with a focus on efficacy, safety, and renal function. Stones requiring percutaneous nephrolithotomy (PCNL) in patients with solitary kidneys can pose significant anxiety to the urologist. Limited data are available in published reports in this setting. A comprehensive retrospective review of medical records was performed on patients who underwent PCNL and had a solitary kidney or a single functioning renal unit. Data were collected on patient demographics, stone burden, outcomes, complications, and renal function. Of 378 PCNLs performed between January 2003 and September 2011, 22 were performed in 17 patients with a single functioning kidney. Three procedures were performed in a transplanted kidney. In those with solitary calculus, the longest mean length and stone surface area were 37 mm and 825 mm(2), respectively. Stone-free rate was 59%. Auxiliary procedures were required in 6 cases, resulting in a stone-free rate of 77%. Median inpatient stay was 4 days. Serum creatinine values improved from 144 to 126 umol/L before and after the procedure and mean estimated glomerular filtration rate improved similarly from 51 to 59 mls/minute, respectively. Blood transfusion was required in 1 patient, sepsis developed in 3, and 2 patients required a stent for obstruction. PCNL in solitary kidneys is safe with an acceptable complication rate if performed in a high volume center. Outcomes are good, although auxiliary procedures may be necessary. Renal function remains stable or improves after procedure. Copyright © 2013 Elsevier Inc. All rights reserved.
Model for a collimated spin wave beam generated by a single layer, spin torque nanocontact
Hoefer, M. A.; Silva, T. J.; Stiles, M. D.
2007-01-01
A model of spin torque induced magnetization dynamics based upon semi-classical spin diffusion theory for a single layer nanocontact is presented. The model incorporates effects due to the current induced Oersted field and predicts the generation of a variety of spatially dependent, coherent, precessional magnetic wave structures. Directionally controllable collimated spin wave beams, vortex spiral waves, and localized standing waves are found to be excited by the interplay of the Oersted fie...
Solitary magnetohydrodynamic vortices
International Nuclear Information System (INIS)
Silaev, I.I.; Skvortsov, A.T.
1990-01-01
This paper reports on the analytical description of fluid flow by means of localized vortices which is traditional for hydrodynamics, oceanology, plasma physics. Recently it has been widely applied to different structure turbulence models. Considerable results involved have been presented where it was shown that in magnetohydrodynamics alongside with the well-known kinds of localized vortices (e.g. Hill's vortex), which are characterized by quite a weak decrease of disturbed velocity or magnetic field (as a power of the inverse distance from vortex center), the vortices with screening (or solitary vortices) may exist. All disturbed parameters either exponentially vanish or become identically zero in outer region in the latter case. (In a number of papers numerical simulations of such the vortices are presented). Solutions in a form of solitary vortices are of particular interest due to their uniformity and solitonlike behavior. On the basis of these properties one can believe for such structures to occur in real turbulent flows
International Nuclear Information System (INIS)
Pakzad, Hamid Reza
2009-01-01
The propagation of nonlinear waves in warm dusty plasmas with variable dust charge, two temperature ion and nonthermal electron is studied. By using the reductive perturbation theory, the Kadomstev-Petviashivili (KP) equation is derived. Existence of rarefactive and compressive solitons is analyzed.
Single point methods for determining blast wave injury
Teland, J.A.; Doormaal, J.C.A.M. van; Horst, M.J. van der; Svinsas, E.
2011-01-01
Models for calculating human injury from a blast wave are examined. The Axelsson BTD model is able to give injury estimates also for complex shock waves, but is difficult to use in practise since it requires input from four pressure sensors on a BTD (Blast Test Device) in the specific location. To
Vlasov Simulation of Electrostatic Solitary Structures in Multi-Component Plasmas
Umeda, Takayuki; Ashour-Abdalla, Maha; Pickett, Jolene S.; Goldstein, Melvyn L.
2012-01-01
Electrostatic solitary structures have been observed in the Earth's magnetosheath by the Cluster spacecraft. Recent theoretical work has suggested that these solitary structures are modeled by electron acoustic solitary waves existing in a four-component plasma system consisting of core electrons, two counter-streaming electron beams, and one species of background ions. In this paper, the excitation of electron acoustic waves and the formation of solitary structures are studied by means of a one-dimensional electrostatic Vlasov simulation. The present result first shows that either electron acoustic solitary waves with negative potential or electron phase-space holes with positive potential are excited in four-component plasma systems. However, these electrostatic solitary structures have longer duration times and higher wave amplitudes than the solitary structures observed in the magnetosheath. The result indicates that a high-speed and small free energy source may be needed as a fifth component. An additional simulation of a five-component plasma consisting of a stable four-component plasma and a weak electron beam shows the generation of small and fast electron phase-space holes by the bump-on-tail instability. The physical properties of the small and fast electron phase-space holes are very similar to those obtained by the previous theoretical analysis. The amplitude and duration time of solitary structures in the simulation are also in agreement with the Cluster observation.
Solitary intraosseous neurofibroma of mandible.
Directory of Open Access Journals (Sweden)
Vivek N
2006-01-01
Full Text Available Solitary intraosseous neurofibroma is a rare benign non-odontogenic tumor. Although neurofibromas occur predominantly as a feature of neurofibromatosis affecting the soft tissue, a few cases of solitary intraosseous neurofibromas of the jaw have been reported. We herewith report a case of solitary intraosseous neurofibroma of mandible in a middle-aged woman with a discussion on its clinical, radiological, and histopathological presentation along with review of cases.
Numerical Simulations of Calcium Ions Spiral Wave in Single Cardiac Myocyte
Bai, Yong-Qiang; Zhu, Xing
2010-04-01
The calcium ions (Ca2+) spark is an elementary Ca2+ release event in cardiac myocytes. It is believed to buildup cell-wide Ca2+ signals, such as Ca2+ transient and Ca2+ wave, through a Ca2+-induced Ca2+ release (CICR) mechanism. Here the excitability of the Ca2+ wave in a single cardiac myocyte is simulated by employing the fire-diffuse-fire model. By modulating the dynamic parameters of Ca2+ release and re-uptake channels, we find three Ca2+ signaling states in a single cardiac myocyte: no wave, plane wave, and spiral wave. The period of a spiral wave is variable in the different regimes. This study indicates that the spiral wave or the excitability of the system can be controlled through micro-modulation in a living excitable medium.
The relationship between elastic constants and structure of shock waves in a zinc single crystal
Krivosheina, M. N.; Kobenko, S. V.; Tuch, E. V.
2017-12-01
The paper provides a 3D finite element simulation of shock-loaded anisotropic single crystals on the example of a Zn plate under impact using a mathematical model, which allows for anisotropy in hydrostatic stress and wave velocities in elastic and plastic ranges. The simulation results agree with experimental data, showing the absence of shock wave splitting into an elastic precursor and a plastic wave in Zn single crystals impacted in the [0001] direction. It is assumed that the absence of an elastic precursor under impact loading of a zinc single crystal along the [0001] direction is determined by the anomalously large ratio of the c/a-axes and close values of the propagation velocities of longitudinal and bulk elastic waves. It is shown that an increase in only one elastic constant along the [0001] direction results in shock wave splitting into an elastic precursor and a shock wave of "plastic" compression.
2015-09-30
1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Observation of the Near-seabed Velocity and Particles...turbulence interaction and/or the dynamic pressure perturbation induced by ISWs cause the resuspension and redistribution of sediment particles and...likely form the continuous sediment waves on the seafloor [Ma et al., 2008 and Reeder et al., 2011]. To our knowledge, there are no direct observations
Molding acoustic, electromagnetic and water waves with a single cloak
Xu, Jun
2015-06-09
We describe two experiments demonstrating that a cylindrical cloak formerly introduced for linear surface liquid waves works equally well for sound and electromagnetic waves. This structured cloak behaves like an acoustic cloak with an effective anisotropic density and an electromagnetic cloak with an effective anisotropic permittivity, respectively. Measured forward scattering for pressure and magnetic fields are in good agreement and provide first evidence of broadband cloaking. Microwave experiments and 3D electromagnetic wave simulations further confirm reduced forward and backscattering when a rectangular metallic obstacle is surrounded by the structured cloak for cloaking frequencies between 2.6 and 7.0 GHz. This suggests, as supported by 2D finite element simulations, sound waves are cloaked between 3 and 8 KHz and linear surface liquid waves between 5 and 16 Hz. Moreover, microwave experiments show the field is reduced by 10 to 30 dB inside the invisibility region, which suggests the multi-wave cloak could be used as a protection against water, sonic or microwaves. © 2015, Nature Publishing Group. All rights reserved.
Maehana, Takeshi; Tanaka, Toshiaki; Kitamura, Hiroshi; Masumori, Naoya; Tsukamoto, Taiji
2013-12-01
We retrospectively investigated short-term functional and oncological outcomes of partial nephrectomy (PN) for the anatomically or functionally solitary kidney in patients with renal cell carcinoma. Between 1993 and 2011, 193 partial nephrectomies were performed and 16 (8.3 %) had an imperative indication in our institution. The patients' characteristics, peri- and postoperative complications, surgical margin status and postoperative changes in estimated glomerular filtration rates (eGFR) were assessed. The median follow-up period was 31.2 months and median age was 69.5 years. Open and laparoscopic PN were performed for 13 and 2 patients, respectively. One patient received ex-vivo PN followed by autotransplantation. There was no case with a positive surgical margin. All patients survived at the final day of observation. Median preoperative eGFR was 48.67 mL/min/1.73 m(2) and the reduction rate of eGFR at 3 months after operation was 20.9 % (0-50.2). Three patients (18.8 %) required temporary hemodialysis after operation and all these patients had stage 4 chronic kidney disease (CKD) before operation. Only one patient needed chronic hemodialysis at 8 months after operation. PN can be performed safely and provides feasible functional and oncological outcomes. Preoperative CKD stage 4 patients may have a risk of temporary hemodialysis in the perioperative period.
Wapenaar, Kees
2017-06-01
A unified scalar wave equation is formulated, which covers three-dimensional (3D) acoustic waves, 2D horizontally-polarised shear waves, 2D transverse-electric EM waves, 2D transverse-magnetic EM waves, 3D quantum-mechanical waves and 2D flexural waves. The homogeneous Green's function of this wave equation is a combination of the causal Green's function and its time-reversal, such that their singularities at the source position cancel each other. A classical representation expresses this homogeneous Green's function as a closed boundary integral. This representation finds applications in holographic imaging, time-reversed wave propagation and Green's function retrieval by cross correlation. The main drawback of the classical representation in those applications is that it requires access to a closed boundary around the medium of interest, whereas in many practical situations the medium can be accessed from one side only. Therefore, a single-sided representation is derived for the homogeneous Green's function of the unified scalar wave equation. Like the classical representation, this single-sided representation fully accounts for multiple scattering. The single-sided representation has the same applications as the classical representation, but unlike the classical representation it is applicable in situations where the medium of interest is accessible from one side only.
International Nuclear Information System (INIS)
He Jianhong; Guo Huazhong; Song Li; Zhang Wei; Gao Jie; Lu Chuan
2010-01-01
We present a comprehensive study of the effects of two counterpropagating surface acoustic waves on the acoustoelectric current of single electron transport devices. A significant improvement in the accuracy of current quantization is achieved as a result of an additional surface acoustic wave beam. The experiments reveal the sinusoidally periodical modulation in the acoustoelectric current characteristic as a function of the relative phase of the two surface acoustic wave beams. Besides, by using standing surface acoustic waves, the acoustoelectric current is detected which we consider as the so-called anomalous acoustoelectric current produced by acoustic wave mechanical deformations. This kind current is contributed to one component of the acoustoelectric current in surface acoustic wave device, which could enable us to establish a more adequate description of acoustoelectric effects on single-electron acoustic charge transport.
Spin-wave propagation and spin-polarized electron transport in single-crystal iron films
Gladii, O.; Halley, D.; Henry, Y.; Bailleul, M.
2017-11-01
The techniques of propagating spin-wave spectroscopy and current-induced spin-wave Doppler shift are applied to a 20-nm-thick Fe/MgO(001) film. The magnetic parameters extracted from the position of the spin-wave resonance peaks are very close to those tabulated for bulk iron. From the zero-current propagating wave forms, a group velocity of 4 km/s and an attenuation length of about 6 μ m are extracted for 1.6-μ m -wavelength spin wave at 18 GHz. From the measured current-induced spin-wave Doppler shift, we extract a surprisingly high degree of spin polarization of the current of 83 % , which constitutes the main finding of this work. This set of results makes single-crystalline iron a promising candidate for building devices utilizing high-frequency spin waves and spin-polarized currents.
Stochastic gravitational wave background from the single-degenerate channel of type Ia supernovae
International Nuclear Information System (INIS)
Falta, David; Fisher, Robert
2011-01-01
We demonstrate that the integrated gravitational wave signal of type Ia supernovae (SNe Ia) in the single-degenerate channel out to cosmological distances gives rise to a continuous background to spaceborne gravitational wave detectors, including the Big Bang Observer and Deci-Hertz Interferometer Gravitational wave Observatory planned missions. This gravitational wave background from SNe Ia acts as a noise background in the frequency range 0.1-10 Hz, which heretofore was thought to be relatively free from astrophysical sources apart from neutron-star and white-dwarf binaries, and therefore a key window in which to study primordial gravitational waves generated by inflation. While inflationary energy scales of > or approx. 10 16 GeV yield inflationary gravitational wave backgrounds in excess of our range of predicted backgrounds, for lower energy scales of ∼10 15 GeV, the inflationary gravitational wave background becomes comparable to the noise background from SNe Ia.
African Journal of Science and Technology (AJST) SOLITARY ...
African Journals Online (AJOL)
Department of Physics, University of Yaounde 1, Yaoundé, Cameroon. E-mail: lenouo@yahoo.fr. ABSTRACT: Weakly nonlinear .... By using a multiple scale method, we can write a stream function ψ in the form of a ..... applicable to description of Rossby solitary waves. This requires the choice of additional wind speed C1.
Is DNA a nonlinear dynamical system where solitary conformational ...
Indian Academy of Sciences (India)
Unknown
DNA is considered as a nonlinear dynamical system in which solitary conformational waves can be excited. The history of the approach, the main results, and arguments in favour and against are presented. Perspectives are discussed pertaining to studies of DNA's nonlinear properties. 1. Introduction. In recent years, many ...
Is DNA a nonlinear dynamical system where solitary conformational ...
Indian Academy of Sciences (India)
Unknown
DNA is considered as a nonlinear dynamical system in which solitary conformational waves can be excited. The history of the approach, the ..... nucleotides; K is the coupling constant along each strand;. R0 is the radius of DNA; a is .... Let us note that the system of equations (12)–(17) can be divided into two independent ...
Fiber-laser-pumped continuous-wave singly resonant optical parametric oscillator
Gross, P.; Klein, M.E.; Walde, T.; Boller, Klaus J.; Auerbach, M.; Wessels, P.; Fallnich, C.
2002-01-01
We report on what is to our knowledge the first continuous-wave (cw) optical parametric oscillator (OPO) that is pumped by a tunable fiber laser. The OPO is singly resonant for the signal wave and consists of a 40-mm-long periodically poled LiNbO3 crystal in a four-mirror ring cavity. At a pump
The classification of the single travelling wave solutions to the ...
Indian Academy of Sciences (India)
2016-09-21
Sep 21, 2016 ... For example,. Fan used Liu's method [11,12] to invest the generalized equal width equation and Pochhammer–Chree equa- tion, and she obtained all the possible travelling wave solutions including elliptic functions and hyperelliptic functions. In this paper, we consider the variant Boussinesq equations [13].
Resorlu, Berkan; Kara, Cengiz; Oguz, Ural; Bayindir, Mirze; Unsal, Ali
2011-06-01
Treatment of patients with solitary kidney having complex stones is one of the most challenging problem in urology. We present our experience with percutaneous nephrolithotomy (PCNL) in treating 16 patients with staghorn stones in a solitary kidney to determine long-term renal functional results. We retrospectively reviewed the records of 16 patients with complex caliceal or staghorn stones in a solitary kidney treated with PCNL. Demographic data, number and location of accesses, hemoglobin values, stone analyses, and complications were studied. Serum creatinine, glomerular filtration rate (GFR), systolic and diastolic blood pressure, new onset hypertension, and kidney morphology were determined preoperatively and postoperatively at 1 month and 1 year. Male to female ratio was 14:2 and mean age was 49.6 years (range 31-55). Of these, 10 (62.5%) patients required a single tract, while 6 (37.5%) required multiple tracts. The calculi were extracted or fragmented successfully in 13 (81.3%) patients and complete stone clearance was achieved after the first stage. In two patients with residual calculi, a double-J catheter was inserted and extracorporeal shock wave lithotripsy (SWL) was performed. There were no significant intraoperative problems except in one patient, who had bleeding from an infundibular tear attributable to torquing. During the 1-year study period, none of the patients progressed to end-stage renal disease requiring dialysis. We demonstrated a significant improvement in creatinine and GFR levels from preoperatively to 1-year follow-up. The number of patients with hypertension before PCNL was 5 and by the end of follow-up there was no new onset hypertension. The demonstrated effectiveness, small number of complications at short-term, not any poorly effect on renal function and blood pressure at the long-term follow-up confirm that PCNL is not only effective but is also safe in the solitary kidney with staghorn calculi.
Pilot-wave quantum theory with a single Bohm's trajectory
Avanzini, Francesco; Fresch, Barbara; Moro, Giorgio J.
2015-01-01
The representation of a quantum system as the spatial configuration of its constituents evolving in time as a trajectory under the action of the wave-function, is the main objective of the Bohm theory. However, its standard formulation is referred to the statistical ensemble of its possible trajectories. The statistical ensemble is introduced in order to establish the exact correspondence (the Born's rule) between the probability density on the spatial configurations and the quantum distribut...
Pitch-angle scattering driven by a single wave in Tokamak plasma
International Nuclear Information System (INIS)
Qiu Yunqing; Xia Mengfen
1988-01-01
The interaction of particles with a single wave in a Tokamak plasma is investigated. It is pointed out that the stochastic pitch-angle scattering across the trapped/passing boundary may be driven by a single wave. The characteristics of such separatrix crossings are discussed. It is also found that the wave-driven separatrix crossings are accompanied by a radial flow of particles, which is composed of a directional flow and a diffusional flow. The resultant pitch-angle and radial fluxes are calculated. (author)
Directory of Open Access Journals (Sweden)
Renu M Magdum
2014-01-01
Full Text Available Schwannomas are rare benign tumors arising from Schwann cells of peripheral nerves that form the neural sheath. While there have been reports of such tumors in the orbit, solitary schwannomas arising from the eyelids are very rare. There are reports of schwannomas being erroneously diagnosed as chalazion, inclusion cysts or even eyelid malignancy. We are reporting a case of a 20-year-old female who presented with a painless, non-tender, slow-growing mass in the upper eyelid of the right eye. The external appearance of the mass was suggestive of an implantation cyst of the eyelid and it could be completely excised as it had a well-defined capsule. Histopathological examination showed characteristic hypercellular and hypocellular areas with fusiform nuclei that tended to form palisades. The purpose of reporting this case of schwannoma in a young female is to recommend the inclusion of this entity as a differential diagnosis of well-defined lid tumors.
Solitary solution for the Kadomstev- Petviashvili equation at critical density
International Nuclear Information System (INIS)
Elhanbly, A.M.; El-shawey, E.K.; Radwan, N.K.; El-kamash, I.S.
2011-01-01
The nonlinear properties of small amplitude electron-acoustic solitary waves ( EASWs) in a homogeneous system of unmagnetized collisionless plasma consisted of a cold electron fluid and isothermal ions with two different temperatures obeying Boltzmann type distributions have been investigated.A reductive perturbation method was employed to obtain the Kadomstev-Petviashvili (KP) equation.At the critical density, the KP equation is not appropriate for describing the system. Hence, a new set of stretched coordinates is considered to derive the modified KP equation. The present investigation can be of relevance to the electrostatic solitary structures observed in various space plasma environments
Longitudinal wave function control in single quantum dots with an applied magnetic field.
Cao, Shuo; Tang, Jing; Gao, Yunan; Sun, Yue; Qiu, Kangsheng; Zhao, Yanhui; He, Min; Shi, Jin-An; Gu, Lin; Williams, David A; Sheng, Weidong; Jin, Kuijuan; Xu, Xiulai
2015-01-27
Controlling single-particle wave functions in single semiconductor quantum dots is in demand to implement solid-state quantum information processing and spintronics. Normally, particle wave functions can be tuned transversely by an perpendicular magnetic field. We report a longitudinal wave function control in single quantum dots with a magnetic field. For a pure InAs quantum dot with a shape of pyramid or truncated pyramid, the hole wave function always occupies the base because of the less confinement at base, which induces a permanent dipole oriented from base to apex. With applying magnetic field along the base-apex direction, the hole wave function shrinks in the base plane. Because of the linear changing of the confinement for hole wave function from base to apex, the center of effective mass moves up during shrinking process. Due to the uniform confine potential for electrons, the center of effective mass of electrons does not move much, which results in a permanent dipole moment change and an inverted electron-hole alignment along the magnetic field direction. Manipulating the wave function longitudinally not only provides an alternative way to control the charge distribution with magnetic field but also a new method to tune electron-hole interaction in single quantum dots.
Exact travelling wave solutions for the generalized shallow water wave equation
International Nuclear Information System (INIS)
Elwakil, S.A.; El-labany, S.K.; Zahran, M.A.; Sabry, R.
2003-01-01
Using homogeneous balance method an auto-Baecklund transformation for the generalized shallow water wave equation is obtained. Then solitary wave solutions are found. Also, modified extended tanh-function method is applied and new exact travelling wave solutions are obtained. The obtained solutions include rational, periodical, singular and solitary wave solutions
Exact travelling wave solutions for the generalized shallow water wave equation
Energy Technology Data Exchange (ETDEWEB)
Elwakil, S.A.; El-labany, S.K.; Zahran, M.A.; Sabry, R
2003-07-01
Using homogeneous balance method an auto-Baecklund transformation for the generalized shallow water wave equation is obtained. Then solitary wave solutions are found. Also, modified extended tanh-function method is applied and new exact travelling wave solutions are obtained. The obtained solutions include rational, periodical, singular and solitary wave solutions.
Bifurcation analysis and the travelling wave solutions of the Klein ...
Indian Academy of Sciences (India)
dynamical system approach, Zhang et al obtained the travelling wave solutions in terms of bright and dark optical solitons and the cnoidal waves. The authors found that eq. (1.5) has only three types of bounded travelling wave solutions, namely, bell-shaped solitary wave solutions, kink-shaped solitary wave solutions and ...
Directory of Open Access Journals (Sweden)
Georgi Tchernev
2017-12-01
CONCLUSION: The affection of a single lymph node in the absence of a primary tumour should not automatically lead to the conclusion that it is a single metastasis, but rather a primary melanoma of the lymph nodes, in cases of a negative PET scan, for example. In these cases, the measuring of the tumour thickness should guide the further therapeutic behaviour and determine the approach.
Dust ion acoustic solitary structures in the presence of isothermal positrons
Energy Technology Data Exchange (ETDEWEB)
Paul, A. [Jadavpur University, Department of Mathematics (India); Das, A. [B. N. S. U. P. School (India); Bandyopadhyay, A., E-mail: abandyopadhyay1965@gmail.com [Jadavpur University, Department of Mathematics (India)
2017-02-15
The Sagdeev potential technique has been employed to study the dust ion acoustic solitary waves and double layers in an unmagnetized collisionless dusty plasma consisting of negatively charged static dust grains, adiabatic warm ions, isothermally distributed electrons, and positrons. A computational scheme has been developed to draw the qualitatively different compositional parameter spaces or existence domains showing the nature of existence of different solitary structures with respect to any parameter of the present plasma system. The present system supports both positive and negative potential double layers. The negative potential double layer always restricts the occurrence of negative potential solitary waves, i.e., any sequence of negative potential solitary waves having monotonically increasing amplitude converges to a negative potential double layer. However, there exists a parameter regime for which the positive potential double layer is unable to restrict the occurrence of positive potential solitary waves. As a result, in this region of the parameter space, there exist solitary waves after the formation of positive potential double layer, i.e., positive potential supersolitons have been observed.
Millimeter-Wave Dielectric Properties of Single Crystal Ferroelectric and Dielectric Materials
Energy Technology Data Exchange (ETDEWEB)
McCloy, John S.; Korolev, Konstantin A.; Li, Zijing; Afsar, Mohammed N.; Sundaram, S. K.
2011-01-03
Transmittance measurements on various single crystal ferroelectric materials over a broad millimeter-wave frequency range have been performed. Frequency dependence of the complex dielectric permittivity has been determined in the millimeter wave region for the first time. The measurements have been employed using a free-space quasi-optical millimeter-wave spectrometer equipped with a set of high power backward wave oscillators (BWOs) as sources of coherent radiation, tunable in the range from 30 - 120 GHz. The uncertainties and possible sources of instrumentation and measurement errors related to the free-space millimeter-wave technique are discussed. This work has demonstrated that precise MMW permittivities can be obtained even on small thin crystals using the BWO quasi-optical approach.
Classification of All Single Travelling Wave Solutions to Calogero-Degasperis-Focas Equation
International Nuclear Information System (INIS)
Liu Chengshi
2007-01-01
Under the travelling wave transformation, Calogero-Degasperis-Focas equation is reduced to an ordinary differential equation. Using a symmetry group of one parameter, this ODE is reduced to a second-order linear inhomogeneous ODE. Furthermore, we apply the change of the variable and complete discrimination system for polynomial to solve the corresponding integrals and obtained the classification of all single travelling wave solutions to Calogero-Degasperis-Focas equation.
Single Tracking Location Methods Suppress Speckle Noise in Shear Wave Velocity Estimation
Elegbe, Etana C.; McAleavey, Stephen A.
2013-01-01
In ultrasound-based elastography methods, the estimation of shear wave velocity typically involves the tracking of speckle motion due to an applied force. The errors in the estimates of tissue displacement, and thus shear wave velocity, are generally attributed to electronic noise and decorrelation due to physical processes. We present our preliminary findings on another source of error, namely, speckle-induced bias in phase estimation. We find that methods that involve tracking in a single l...
Single Crystal Substrates for Surface Acoustic Wave Devices.
1981-01-01
81 G R BARSCH. K E SPEAR F19628-79-C-0036 UNCLASSIFIED RADC-TR-8-398 ML U EEE~EE.TIE OZO 91 1S RADC-T40498 Final Technical Rput January 1981 SINGLE...tangent for c-berlinite (Rarsch and Spear, lq79) have been repeated and extended to lower frequencies by usina a fully automated Hewlett Packard Model ...with a Keithley Model 616 Digital Electrometer. For the Z-cut platelet (grown hydrothermally at the Naval Weapons Center, China Lake, California) a
Solitary waves in nematic liquid crystals
Panayotaros, Panayotis; Marchant, T. R.
2014-02-01
We study soliton solutions of a two-dimensional nonlocal NLS equation of Hartree-type with a Bessel potential kernel. The equation models laser propagation in nematic liquid crystals. Motivated by the experimental observation of spatially localized beams, see Conti et al. (2003), we show existence, stability, regularity, and radial symmetry of energy minimizing soliton solutions in R2. We also give theoretical lower bounds for the L2-norm (power) of these solitons, and show that small L2-norm initial conditions lead to decaying solutions. We also present numerical computations of radial soliton solutions. These solutions exhibit the properties expected by the infinite plane theory, although we also see some finite (computational) domain effects, especially solutions with arbitrarily small power.
Double-slit experiment with single wave-driven particles and its relation to quantum mechanics
DEFF Research Database (Denmark)
Andersen, Anders Peter; Madsen, Jacob; Reichelt, Christian Günther
2015-01-01
even though it is possible to determine unambiguously which slit the walking droplet passes. Here we argue, however, that the single-particle statistics in such an experiment will be fundamentally different from the single-particle statistics of quantum mechanics. Quantum mechanical interference takes......¨dinger equation with a source term originating from a localized particle that generates a wave while being simultaneously guided by it. We show that the ensuing particle-wave dynamics can capture some characteristics of quantum mechanics such as orbital quantization. However, the particle-wave dynamics can...... not reproduce quantum mechanics in general, and we show that the single-particle statistics for our model in a double-slit experiment with an additional splitter plate differs qualitatively from that of quantum mechanics....
Different quantization mechanisms in single-electron pumps driven by surface acoustic waves
DEFF Research Database (Denmark)
Utko, P.; Gloos, K.; Hansen, Jørn Bindslev
2006-01-01
We have studied the acoustoelectric current in single-electron pumps driven by surface acoustic waves. We have found that in certain parameter ranges two different sets of quantized steps dominate the acoustoelectric current versus gate-voltage characteristics. In some cases, both types of quanti......We have studied the acoustoelectric current in single-electron pumps driven by surface acoustic waves. We have found that in certain parameter ranges two different sets of quantized steps dominate the acoustoelectric current versus gate-voltage characteristics. In some cases, both types...
International Nuclear Information System (INIS)
Lerma H, S.
2010-01-01
The structure of the exact wave function of the isovectorial pairing Hamiltonian with nondegenerate single-particle levels is discussed. The way that the single-particle splittings break the quartet condensate solution found for N=Z nuclei in a single degenerate level is established. After a brief review of the exact solution, the structure of the wave function is analyzed and some particular cases are considered where a clear interpretation of the wave function emerges. An expression for the exact wave function in terms of the isospin triplet of pair creators is given. The ground-state wave function is analyzed as a function of pairing strength, for a system of four protons and four neutrons. For small and large values of the pairing strength a dominance of two-pair (quartets) scalar couplings is found, whereas for intermediate values enhancements of the nonscalar couplings are obtained. A correlation of these enhancements with the creation of Cooper-like pairs is observed.
Polarization dependence of the spin-density-wave excitations in single-domain chromium
Energy Technology Data Exchange (ETDEWEB)
Boeni, P. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Roessli, B. [Institut Max von Laue - Paul Langevin, 75 - Paris (France); Sternlieb, B.J. [Brookhaven (United States); Lorenzo, E. [Centre National de la Recherche Scientifique (CNRS), 38 - Grenoble (France); Werner, S.A. [Missouri (United States)
1997-09-01
A polarized neutron scattering experiment has been performed with a single-Q, single domain sample of chromium in a magnetic field of 4 T. It is confirmed that the longitudinal fluctuations are enhanced for small energy transfers and that the spin wave modes with {delta}S parallel to Q and {delta}S perpendicular to Q are similar. (author) 2 figs., 1 tab., 2 refs.
Ebrahimi, Farzad; Dabbagh, Ali
2018-04-01
In the present article, the hygro-thermal wave propagation properties of single-layered graphene sheets (SLGSs) are investigated for the first time employing a nonlocal strain gradient theory. A refined higher-order two-variable plate theory is utilized to derive the kinematic relations of graphene sheets. Here, nonlocal strain gradient theory is used to achieve a more precise analysis of small-scale plates. In the framework of the Hamilton's principle, the final governing equations are developed. Moreover, these obtained equations are deemed to be solved analytically and the wave frequency values are achieved. Some parametric studies are organized to investigate the influence of different variants such as nonlocal parameter, length scale parameter, wave number, temperature gradient and moisture concentration on the wave frequency of graphene sheets.
Theory of energy and power flow of plasmonic waves on single-walled carbon nanotubes
Moradi, Afshin
2017-10-01
The energy theorem of electrodynamics is extended so as to apply to the plasmonic waves on single-walled carbon nanotubes which propagate parallel to the axial direction of the system and are periodic waves in the azimuthal direction. Electronic excitations on the nanotube surface are modeled by an infinitesimally thin layer of free-electron gas which is described by means of the linearized hydrodynamic theory. General expressions of energy and power flow associated with surface waves are obtained by solving Maxwell and hydrodynamic equations with appropriate boundary conditions. Numerical results for the transverse magnetic mode show that energy, power flow, and energy transport velocity of the plasmonic waves strongly depend on the nanotube radius in the long-wavelength region.
Ulcerative giant solitary trichoepithelioma of scalp: a rare presentation
Directory of Open Access Journals (Sweden)
Sundeep Chowdhry
2016-07-01
Full Text Available Trichoepithelioma is a trichogenic tumor which arises from the inferior segment of hair follicle epithelium as hamartoma. Giant solitary trichoepithelioma (GST has been defined as a solitary trichoepithelioma with a diameter greater than 2 cm. A 49-year-old female presented with a slow growing skin coloured swelling on the scalp of 8 years duration with recent history of ulceration and occasional bleeding. The local examination revealed a single well defined nodular swelling which was irregular in shape measuring approximately 2 × 2.5 cm. Histopathology from biopsy specimen revealed dark basaloid cells with scanty cytoplasm and darkly stained nucleus arranged in nests with horn cysts lacking high-grade atypia and mitosis, which was consistent with features of trichoepithelioma. Giant solitary trichoepithelioma of scalp is itself a rare entity and the present case is being reported with the additional component of ulceration in the lesion.
International Nuclear Information System (INIS)
Zhang Hai-Yan; Yu Jian-Bo
2011-01-01
Excitation and propagation of Lamb waves by using rectangular and circular piezoelectric transducers surface-bonded to an isotropic plate are investigated in this work. Analytical stain wave solutions are derived for the two transducer shapes, giving the responses of these transducers in Lamb wave fields. The analytical study is supported by a numerical simulation using the finite element method. Symmetric and antisymmetric components in the wave propagation responses are inspected in detail with respect to test parameters such as the transducer geometry, the length and the excitation frequency. By placing only one piezoelectric transducer on the top or the bottom surface of the plate and weakening the strength of one mode while enhancing the strength of the other modes to find the centre frequency, with which the peak wave amplitude ratio between the S0 and A0 modes is maximum, a single mode excitation from the multiple modes of the Lamb waves can be achieved approximately. Experimental data are presented to show the validity of the analyses. The results are used to optimize the Lamb wave detection system. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
Current Mode Full-Wave Rectifier Based on a Single MZC-CDTA
Directory of Open Access Journals (Sweden)
Neeta Pandey
2013-01-01
Full Text Available This paper presents a current mode full-wave rectifier based on single modified Z copy current difference transconductance amplifier (MZC-CDTA and two switches. The circuit is simple and is suitable for IC implementation. The functionality of the circuit is verified with SPICE simulation using 0.35 μm TSMC CMOS technology parameters.
Solitary eccrine syringofibroadenoma - Case Report*
Bottino, Caroline Bertolini; Guimarães, Tais Ferreira; Gomes, Flávio Rezende; D'Acri, Antonio Macedo; Lima, Ricardo Barbosa; Martins, Carlos José
2015-01-01
Eccrine syringofibroadenoma is a rare benign adnexal neoplasm derived from cells of the acrosyringium of eccrine sweat glands. ESFA usually manifests as a solitary nodule on the extremities of elderly patients, but it may also present as papules, nodules or plaques. Its clinical appearance is nonspecific and malignant neoplasms should beconsidered in the differential diagnosis. However, histopathological findings are typical. The main treatment is surgical excision. In order to illustrate a typical presentation of the tumor, we report a case of solitary eccrine syringofibroadenoma, including the surgical treatment used and its result. PMID:26312727
Aging and body size in solitary bees
Solitary bees are important pollinators of crops and non-domestic plants. Osmia lignaria is a native, commercially-reared solitary bee used to maximize pollination in orchard crops. In solitary bees, adult body size is extremely variable depending on the nutritional resources available to the develo...
Continuous-Wave Single-Photon Transistor Based on a Superconducting Circuit
DEFF Research Database (Denmark)
Kyriienko, Oleksandr; Sørensen, Anders Søndberg
2016-01-01
We propose a microwave frequency single-photon transistor which can operate under continuous wave probing and represents an efficient single microwave photon detector. It can be realized using an impedance matched system of a three level artificial ladder-type atom coupled to two microwave cavities...... and the appearance of a photon flux leaving the second cavity through a separate input-output port. The proposal does not require time variation of the probe signals, thus corresponding to a passive version of a single-photon transistor. The resulting device is robust to qubit dephasing processes, possesses low dark...
A single and rapid calcium wave at egg activation in Drosophila
Directory of Open Access Journals (Sweden)
Anna H. York-Andersen
2015-03-01
Full Text Available Activation is an essential process that accompanies fertilisation in all animals and heralds major cellular changes, most notably, resumption of the cell cycle. While activation involves wave-like oscillations in intracellular Ca2+ concentration in mammals, ascidians and polychaete worms and a single Ca2+ peak in fish and frogs, in insects, such as Drosophila, to date, it has not been shown what changes in intracellular Ca2+ levels occur. Here, we utilise ratiometric imaging of Ca2+ indicator dyes and genetically encoded Ca2+ indicator proteins to identify and characterise a single, rapid, transient wave of Ca2+ in the Drosophila egg at activation. Using genetic tools, physical manipulation and pharmacological treatments we demonstrate that the propagation of the Ca2+ wave requires an intact actin cytoskeleton and an increase in intracellular Ca2+ can be uncoupled from egg swelling, but not from progression of the cell cycle. We further show that mechanical pressure alone is not sufficient to initiate a Ca2+ wave. We also find that processing bodies, sites of mRNA decay and translational regulation, become dispersed following the Ca2+ transient. Based on this data we propose the following model for egg activation in Drosophila: exposure to lateral oviduct fluid initiates an increase in intracellular Ca2+ at the egg posterior via osmotic swelling, possibly through mechano-sensitive Ca2+ channels; a single Ca2+ wave then propagates in an actin dependent manner; this Ca2+ wave co-ordinates key developmental events including resumption of the cell cycle and initiation of translation of mRNAs such as bicoid.
Model for a collimated spin-wave beam generated by a single-layer spin torque nanocontact
Hoefer, M. A.; Silva, T. J.; Stiles, M. D.
2008-04-01
A model of spin-torque-induced magnetization dynamics based on semiclassical spin diffusion theory for a single-layer nanocontact is presented. The model incorporates effects due to the current-induced Oersted field and predicts the generation of a variety of spatially dependent, coherent, precessional magnetic wave structures. Directionally controllable collimated spin-wave beams, vortex spiral waves, and localized standing waves are found to be excited by the interplay of the Oersted field and the orientation of an applied field. These fields act as a spin-wave “corral” around the nanocontact that controls the propagation of spin waves in certain directions.
Single tracking location methods suppress speckle noise in shear wave velocity estimation.
Elegbe, Etana C; McAleavey, Stephen A
2013-04-01
In ultrasound-based elastography methods, the estimation of shear wave velocity typically involves the tracking of speckle motion due to an applied force. The errors in the estimates of tissue displacement, and thus shear wave velocity, are generally attributed to electronic noise and decorrelation due to physical processes. We present our preliminary findings on another source of error, namely, speckle-induced bias in phase estimation. We find that methods that involve tracking in a single location, as opposed to multiple locations, are less sensitive to this source of error since the measurement is differential in nature and cancels out speckle-induced phase errors.
International Nuclear Information System (INIS)
Barut, A.O.
1990-06-01
For an arbitrary potential V with classical trajectories x-vector=g-vector(t) we construct localized oscillating three-dimensional wave lumps ψ(x-vector,t,g-vector) representing a single quantum particle. The crest of the envelope of the ripple follows the classical orbit g-vector(t) slightly modified due to potential V and ψ(x-vector,t;g-vector) satisfies the Schroedinger equation. The field energy, momentum and angular momentum calculated as integrals over all space are equal to particle energy, momentum and angular momentum. The relation to coherent states and to Schroedinger waves are also discussed. (author). 6 refs
Double-slit experiment with single wave-driven particles and its relation to quantum mechanics.
Andersen, Anders; Madsen, Jacob; Reichelt, Christian; Rosenlund Ahl, Sonja; Lautrup, Benny; Ellegaard, Clive; Levinsen, Mogens T; Bohr, Tomas
2015-07-01
In a thought-provoking paper, Couder and Fort [Phys. Rev. Lett. 97, 154101 (2006)] describe a version of the famous double-slit experiment performed with droplets bouncing on a vertically vibrated fluid surface. In the experiment, an interference pattern in the single-particle statistics is found even though it is possible to determine unambiguously which slit the walking droplet passes. Here we argue, however, that the single-particle statistics in such an experiment will be fundamentally different from the single-particle statistics of quantum mechanics. Quantum mechanical interference takes place between different classical paths with precise amplitude and phase relations. In the double-slit experiment with walking droplets, these relations are lost since one of the paths is singled out by the droplet. To support our conclusions, we have carried out our own double-slit experiment, and our results, in particular the long and variable slit passage times of the droplets, cast strong doubt on the feasibility of the interference claimed by Couder and Fort. To understand theoretically the limitations of wave-driven particle systems as analogs to quantum mechanics, we introduce a Schrödinger equation with a source term originating from a localized particle that generates a wave while being simultaneously guided by it. We show that the ensuing particle-wave dynamics can capture some characteristics of quantum mechanics such as orbital quantization. However, the particle-wave dynamics can not reproduce quantum mechanics in general, and we show that the single-particle statistics for our model in a double-slit experiment with an additional splitter plate differs qualitatively from that of quantum mechanics.
Double-slit experiment with single wave-driven particles and its relation to quantum mechanics
Andersen, Anders; Madsen, Jacob; Reichelt, Christian; Rosenlund Ahl, Sonja; Lautrup, Benny; Ellegaard, Clive; Levinsen, Mogens T.; Bohr, Tomas
2015-07-01
In a thought-provoking paper, Couder and Fort [Phys. Rev. Lett. 97, 154101 (2006), 10.1103/PhysRevLett.97.154101] describe a version of the famous double-slit experiment performed with droplets bouncing on a vertically vibrated fluid surface. In the experiment, an interference pattern in the single-particle statistics is found even though it is possible to determine unambiguously which slit the walking droplet passes. Here we argue, however, that the single-particle statistics in such an experiment will be fundamentally different from the single-particle statistics of quantum mechanics. Quantum mechanical interference takes place between different classical paths with precise amplitude and phase relations. In the double-slit experiment with walking droplets, these relations are lost since one of the paths is singled out by the droplet. To support our conclusions, we have carried out our own double-slit experiment, and our results, in particular the long and variable slit passage times of the droplets, cast strong doubt on the feasibility of the interference claimed by Couder and Fort. To understand theoretically the limitations of wave-driven particle systems as analogs to quantum mechanics, we introduce a Schrödinger equation with a source term originating from a localized particle that generates a wave while being simultaneously guided by it. We show that the ensuing particle-wave dynamics can capture some characteristics of quantum mechanics such as orbital quantization. However, the particle-wave dynamics can not reproduce quantum mechanics in general, and we show that the single-particle statistics for our model in a double-slit experiment with an additional splitter plate differs qualitatively from that of quantum mechanics.
International Nuclear Information System (INIS)
Geng Tao; Shan Wenrui; Lue Xing; Cai Kejie; Zhang Cheng; Tian Bo
2009-01-01
Fusion and fission phenomena for solitary waves have been discovered theoretically and experimentally. In this paper, the (2 + 1)-dimensional variable-coefficient Broer-Kaup system is symbolically investigated. By employing the bilinear method, new solitary solutions with arbitrary functions are obtained. At the same time, the non-elastic interactions of solitary solutions are graphically studied. Furthermore, soliton fusion and fission phenomena are revealed by choosing appropriate functions.
EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY AS ...
African Journals Online (AJOL)
Objective To evaluate extracorporeal shock wave lithotripsy (ESWL) as a monotherapy for urolithiasis in patients with solitary kidney and to determine the factors that may affect its results. Patients and Methods Using the Dornier MFL 5000 lithotriptor, 106 patients with solitary kidney (80 men and 26 women) were treated for ...
Single actuator wave-like robot (SAW): design, modeling, and experiments.
Zarrouk, David; Mann, Moshe; Degani, Nir; Yehuda, Tal; Jarbi, Nissan; Hess, Amotz
2016-07-01
In this paper, we present a single actuator wave-like robot, a novel bioinspired robot which can move forward or backward by producing a continuously advancing wave. The robot has a unique minimalistic mechanical design and produces an advancing sine wave, with a large amplitude, using only a single motor but with no internal straight spine. Over horizontal surfaces, the robot does not slide relative to the surface and its direction of locomotion is determined by the direction of rotation of the motor. We developed a kinematic model of the robot that accounts for the two-dimensional mechanics of motion and yields the speed of the links relative to the motor. Based on the optimization of the kinematic model, and accounting for the mechanical constraints, we have designed and built multiple versions of the robot with different sizes and experimentally tested them (see movie). The experimental results were within a few percentages of the expectations. The larger version attained a top speed of 57 cm s(-1) over a horizontal surface and is capable of climbing vertically when placed between two walls. By optimizing the parameters, we succeeded in making the robot travel by 13% faster than its own wave speed.
Optical single sideband millimeter-wave signal generation and transmission using 120° hybrid coupler
Zheng, Zhiwei; Peng, Miao; Zhou, Hui; Chen, Ming; Jiang, Leyong; Tan, Li; Dai, Xiaoyu; Xiang, Yuanjiang
2018-03-01
We propose a novel 60 GHz optical single sideband (OSSB) millimeter-wave (mm-wave) signal generation scheme using 120° hybrid coupler based on external integrated Mach-Zehnder modulator (MZM). The proposed scheme shows that the bit error ratio (BER) performance is improved by suppressing the +2nd-order sideband. Meanwhile, the transmission distance is extended as only the optical +1st-order sideband is modulated by using 5 Gbit/s baseband signal while the carrier is blank, owing to the elimination of walk-off effect suffered from fiber dispersion. The simulation results demonstrated that the eye diagrams of the generated 60 GHz OSSB signal keep open and clear after 100 km standard single-mode fiber (SSMF). In addition, the proposed scheme can achieve 2 dB receiver sensitivity improvements than the conventional 90° hybrid coupler when transmitted over 100 km SSMF at a BER of 10-9.
International Nuclear Information System (INIS)
Hayashi, Minoru; Kobayashi, Hidenori; Kawano, Hirokazu; Handa, Yuji; Noguchi, Yoshiyuki; Shirasaki, Naoki; Hirose, Satoshi
1986-01-01
The authors studied brain blood flow with single photon emission computed tomography (SPECT) in two patients with plateau waves. The intracranial pressure and blood pressure were also monitored continuously in these patients. They included one patient with brain-tumor (rt. sphenoid ridge meningioma) and another with hydrocephalus after subarachnoid hemorrhage due to rupture of lt. internal carotid aneurysm. The intracranial pressure was monitored through an indwelling ventricular catheter attached to a pressure transducer. The blood pressure was recorded through an intraarterial catheter placed in the dorsalis pedis artery. Brain blood flow was studied with Headtome SET-011 (manufactured by Shimazu Co., Ltd.). For this flow measurement study, an intravenous injection of Xenon-133 of about 30 mCi was given via an antecubital vein. The position of the slice for the SPECT was selected so as to obtain information not only from the cerebral hemisphere but also from the brain stem : a cross section 25 deg over the orbito-meatal line, passing through the inferior aspect of the frontal horn, the basal ganglia, the lower recessus of the third ventricle and the brain stem. The results indicated that, in the cerebral hemisphere, plateau waves were accompanied by a decrease in blood flow, whereas, in the brain stem, the blood flow showed little change during plateau waves as compared with the interval phase between two plateau waves. These observations may explain why there is no rise in the blood pressure and why patients are often alert during plateau waves. (author)
Chaotic diffusion across a magnetic island due to a single electrostatic drift wave
International Nuclear Information System (INIS)
Misguich, J.H.
1990-05-01
It is shown that the guiding center motion around a single chain of magnetic islands in a Tokamak can become chaotic in the presence of a single electrostatic drift wave. This process leads to radial diffusion across the islands without magnetic braiding. The chaotic diffusion appears to be selective in velocity space. Realistic values of the physical parameters are considered to deduce that this process can be effective in usual conditions: with the observed islands, and electrostatic field values corresponding to measured density fluctuations, this diffusion concerns ions with velocities higher than thermal, and almost all of the electron population. The consequences for radial diffusion are discussed
Optical trapping and Raman spectroscopy of single nanostructures using standing-wave Raman tweezers
Wu, Mu-ying; He, Lin; Chen, Gui-hua; Yang, Guang; Li, Yong-qing
2017-08-01
Optical tweezers integrated with Raman spectroscopy allows analyzing a single trapped micro-particle, but is generally less effective for individual nano-sized objects in the 10-100 nm range. The main challenge is the weak gradient force on nanoparticles that is insufficient to overcome the destabilizing effect of scattering force and Brownian motion. Here, we present standing-wave Raman tweezers for stable trapping and sensitive characterization of single isolated nanostructures with a low laser power by combining a standing-wave optical trap (SWOT) with confocal Raman spectroscopy. This scheme has stronger intensity gradients and balanced scattering forces, and thus is more stable and sensitive in measuring nanoparticles in liquid with 4-8 fold increase in the Raman signals. It can be used to analyze many nanoparticles that cannot be measured with single-beam Raman tweezers, including individual single-walled carbon nanotubes (SWCNT), graphene flakes, biological particles, polystyrene beads (100 nm), SERS-active metal nanoparticles, and high-refractive semiconductor nanoparticles with a low laser power of a few milliwatts. This would enable sorting and characterization of specific SWCNTs and other nanoparticles based on their increased Raman fingerprints.
Lee, Seung-Heon; Lu, Jian; Lee, Seung-Jun; Han, Jae-Hyun; Jeong, Chan-Uk; Lee, Seung-Chul; Li, Xian; Jazbinšek, Mojca; Yoon, Woojin; Yun, Hoseop; Kang, Bong Joo; Rotermund, Fabian; Nelson, Keith A; Kwon, O-Pil
2017-08-01
Highly efficient nonlinear optical organic crystals are very attractive for various photonic applications including terahertz (THz) wave generation. Up to now, only two classes of ionic crystals based on either pyridinium or quinolinium with extremely large macroscopic optical nonlinearity have been developed. This study reports on a new class of organic nonlinear optical crystals introducing electron-accepting benzothiazolium, which exhibit higher electron-withdrawing strength than pyridinium and quinolinium in benchmark crystals. The benzothiazolium crystals consisting of new acentric core HMB (2-(4-hydroxy-3-methoxystyryl)-3-methylbenzo[d]thiazol-3-ium) exhibit extremely large macroscopic optical nonlinearity with optimal molecular ordering for maximizing the diagonal second-order nonlinearity. HMB-based single crystals prepared by simple cleaving method satisfy all required crystal characteristics for intense THz wave generation such as large crystal size with parallel surfaces, moderate thickness and high optical quality with large optical transparency range (580-1620 nm). Optical rectification of 35 fs pulses at the technologically very important wavelength of 800 nm in 0.26 mm thick HMB crystal leads to one order of magnitude higher THz wave generation efficiency with remarkably broader bandwidth compared to standard inorganic 0.5 mm thick ZnTe crystal. Therefore, newly developed HMB crystals introducing benzothiazolium with extremely large macroscopic optical nonlinearity are very promising materials for intense broadband THz wave generation and other nonlinear optical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
From bell-shaped solitary wave to W/M-shaped solitary wave
Indian Academy of Sciences (India)
Technology, Guilin, Guangxi, 541004, People's Republic of China. 3Foundation Department, Southwest Forestry University, Kunming, Yunnan, 650224,. People's Republic of China. *Corresponding author. E-mail: aiyongchen@163.com. MS received 7 October 2008; revised 1 July 2009; accepted 9 September 2009.
From bell-shaped solitary wave to W/M-shaped solitary wave ...
Indian Academy of Sciences (India)
Center of Nonlinear Science Studies, Kunming University of Science and Technology, Kunming, Yunnan, 650093, People's Republic of China; School of Mathematics and Computing Science, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, People's Republic of China; Foundation Department, ...
Solitary Intraosseous Neurofibroma of the Mandible
Directory of Open Access Journals (Sweden)
Hamideh Kadeh
2014-07-01
Full Text Available Neurofibroma is a benign neoplasm derived from peripheral nerve cells. Neurofibroma can occur as a solitary tumor also it may associate with neurofibromatosis. Intraosseous neurofibroma is a rare tumor particularly in the oral cavity. So far, few cases of solitary intraosseous neurofibroma of the mandible have been reported. In the present study, a 39 years old woman which has a diagnosis of solitary intraosseous neurofibroma of the mandible is reported. Clinical, radiographic, histopathologic and immunohistochemical features are described.
Restoration of s-polarized evanescent waves and subwavelength imaging by a single dielectric slab
International Nuclear Information System (INIS)
El Gawhary, Omar; Schilder, Nick J; Costa Assafrao, Alberto da; Pereira, Silvania F; Paul Urbach, H
2012-01-01
It was predicted a few years ago that a medium with negative index of refraction would allow for perfect imaging. Although no material has been found so far that behaves as a perfect lens, some experiments confirmed the theoretical predictions in the near-field, or quasi-static, regime where the behaviour of a negative index medium can be mimicked by a thin layer of noble metal, such as silver. These results are normally attributed to the excitation of surface plasmons in the metal, which only leads to the restoration of p-polarized evanescent waves. In this work, we show that the restoration of s-polarized evanescent waves and, correspondingly, sub-wavelength imaging by a single dielectric slab are possible. Specifically, we show that at λ = 632 nm a thin layer of GaAs behaves as a superlens for s-polarized waves. Replacing the single-metal slab by a dielectric is not only convenient from a technical point of view, it being much easier to deposit and control the thickness and flatness of dielectric films than metal ones, but also invites us to re-think the connection between surface plasmon excitation and the theory of negative refraction. (paper)
Nonlinear effects of a beam interacting with a single damped wave
International Nuclear Information System (INIS)
Stoltz, Peter H.; Cary, John R.
2000-01-01
A self-consistent nonlinear theory of the longitudinal dynamics of a low density beam interacting with a single damped wave is developed. In this paper, the model is applied to the coasting beam-cavity system of accelerator physics, but it also applies to beam-plasma systems and traveling wave tubes. Motivating the theory are numerical simulations showing different beam behaviors in the nonlinear regime depending on the amount of wave damping. For highly damped systems, breakoff and energy loss of a self-formed bunch from the beam is observed. This bunch breakoff and energy loss is the cause of the overshoot phenomenon of accelerator physics; furthermore this overshoot does not contradict the Keil-Schnell criterion, as the beam is far from a Gaussian distribution. An expression for the amount of cavity damping necessary for bunch breakoff is derived. Finally, using a single-particle model, an expression for the rate of energy loss of the bunch in terms of the cavity damping is derived. (c) 2000 American Institute of Physics
Genova, Pietro; Brunetti, Francesco; Bequignon, Emilie; Landi, Filippo; Lizzi, Vincenzo; Esposito, Francesco; Charpy, Cecile; Calderaro, Julien; Azoulay, Daniel; de?Angelis, Nicola
2016-01-01
Background Solitary splenic metastases are a rare occurrence, and the nasopharyngeal carcinoma represents one of the most uncommon primary sources. The present study aimed to describe a rare case of a solitary single splenic metastasis from nasopharyngeal carcinoma and to assess the number of cases of isolated nasopharyngeal carcinoma metastases to the spleen reported in the literature. Main body We describe the case of a 56-year-old man with a history of nasopharyngeal carcinoma and complete...
Solitary wave and periodic wave solutions for Burgers, Fisher ...
Indian Academy of Sciences (India)
2015-11-27
Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November 27, 2015. Guest Editors: Anurag Srivastava, C. S. Praveen, H. S. Tewari. © 2015 Indian Academy of Sciences, Bengaluru. Contact | Site index.
Thee-Dimensional Single-Track-Location Shear Wave Elasticity Imaging.
Hollender, Peter; Lipman, Samantha L; Trahey, Gregg E
2017-12-01
Conventional multiple-track-location shear wave elasticity imaging (MTL-SWEI) is a powerful tool for noninvasively estimating tissue elasticity. The resolution and noise levels of MTL-SWEI systems, however, are limited by ultrasound speckle. Single-track-location SWEI (STL-SWEI) is a novel variant which fixes the position of the tracking beam and modulates the push location to effectively cancel out the effects of speckle-induced bias. We present here a 3-D STL-SWEI system, which provides full suppression of lateral and elevation speckle bias for high-resolution volumetric elasticity imaging, and requires no spatial smoothing to make accurate measurements of shear wave speed. We demonstrate and analyze the system's performance in homogeneous and layered elasticity phantoms.
International Nuclear Information System (INIS)
Chough, Young-Tak; Nha, Hyunchul; Kim, Sang Wook; An, Kyungwon; Youn, Sun-Hyun
2002-01-01
We investigate the single-atom detection system using an optical standing-wave cavity, from the viewpoint of the quantized center-of-mass motion of the atomic wave packet. We show that since the atom-field coupling strength depends upon the overlap integral of the atomic wave packet and the field mode function, the effect of the wave-packet spreading via the momentum exchange process brings about a significant effect in the detection efficiency. We find that, as a result, the detection efficiency is not sensitive to the individual atomic trajectory for reasonably slow atoms. We also address an interesting phenomenon of the atomic wave-packet splitting occurring when an atom passes through a node of the cavity field
Self-Calibrating Wave-Encoded Variable-Density Single-Shot Fast Spin Echo Imaging.
Chen, Feiyu; Taviani, Valentina; Tamir, Jonathan I; Cheng, Joseph Y; Zhang, Tao; Song, Qiong; Hargreaves, Brian A; Pauly, John M; Vasanawala, Shreyas S
2018-04-01
It is highly desirable in clinical abdominal MR scans to accelerate single-shot fast spin echo (SSFSE) imaging and reduce blurring due to T 2 decay and partial-Fourier acquisition. To develop and investigate the clinical feasibility of wave-encoded variable-density SSFSE imaging for improved image quality and scan time reduction. Prospective controlled clinical trial. With Institutional Review Board approval and informed consent, the proposed method was assessed on 20 consecutive adult patients (10 male, 10 female, range, 24-84 years). A wave-encoded variable-density SSFSE sequence was developed for clinical 3.0T abdominal scans to enable high acceleration (3.5×) with full-Fourier acquisitions by: 1) introducing wave encoding with self-refocusing gradient waveforms to improve acquisition efficiency; 2) developing self-calibrated estimation of wave-encoding point-spread function and coil sensitivity to improve motion robustness; and 3) incorporating a parallel imaging and compressed sensing reconstruction to reconstruct highly accelerated datasets. Image quality was compared pairwise with standard Cartesian acquisition independently and blindly by two radiologists on a scale from -2 to 2 for noise, contrast, confidence, sharpness, and artifacts. The average ratio of scan time between these two approaches was also compared. A Wilcoxon signed-rank tests with a P value under 0.05 considered statistically significant. Wave-encoded variable-density SSFSE significantly reduced the perceived noise level and improved the sharpness of the abdominal wall and the kidneys compared with standard acquisition (mean scores 0.8, 1.2, and 0.8, respectively, P variable-density sampling SSFSE achieves improved image quality with clinically relevant echo time and reduced scan time, thus providing a fast and robust approach for clinical SSFSE imaging. 1 Technical Efficacy: Stage 6 J. Magn. Reson. Imaging 2018;47:954-966. © 2017 International Society for Magnetic Resonance in Medicine.
Effects of Single Dose Energy Drink on QT and P-Wave Dispersion
Directory of Open Access Journals (Sweden)
Huseyin Arinc
2013-12-01
Full Text Available INTRODUCTION: Aim of this study is to evaluate the cardiac electrophysiological effects of energy drink (Red Bull on QT and P duration and dispersion on surface electrocardiogram. METHODS: Twenty healthy volunteers older than 17 years of age were included the study. Subjects with a cardiac rhythm except sinus rhythm, history of atrial or ventricular arrhythmia, family history of premature sudden cardiac death, palpitations, T-wave abnormalities, QTc interval greater than 440 milliseconds, or those P-waves and QT intervals unavailable in at least eight ECG leads were excluded. Subjects having insomnia, lactose intolerance, caffeine allergy, recurrent headaches, depression, any psychiatric condition, and history of alcohol or drug abuse, pregnant or lactating women were also excluded from participation. 12 lead ECG was obtained before and after consumption of 250 cc enegry drink. QT and P-wave dispersion was calculated. RESULTS: No significant difference have occurred in heart rate (79 ± 14 vs.81 ±13, p=0.68, systolic pressure (114 ± 14 vs.118 ± 16,p=0.38, diastolic blood pressure (74 ± 12 vs.76 ± 14, p=0.64, QT dispersion (58 ± 12 vs. 57 ± 22, p= 0.785 and P-wave dispersion (37 ± 7 vs. 36 ± 13, p= 0.755 between before and 2 hours after consumption of energy drink. DISCUSSION AND CONCLUSION: Consumption of single dose energy drink doesn't affect QT dispersion and P-wave dispersion, heart rate and blood pressure in healthy adults.
Persistent Charge-Density-Wave Order in Single-Layer TaSe2.
Ryu, Hyejin; Chen, Yi; Kim, Heejung; Tsai, Hsin-Zon; Tang, Shujie; Jiang, Juan; Liou, Franklin; Kahn, Salman; Jia, Caihong; Omrani, Arash A; Shim, Ji Hoon; Hussain, Zahid; Shen, Zhi-Xun; Kim, Kyoo; Min, Byung Il; Hwang, Choongyu; Crommie, Michael F; Mo, Sung-Kwan
2018-02-14
We present the electronic characterization of single-layer 1H-TaSe 2 grown by molecular beam epitaxy using a combined angle-resolved photoemission spectroscopy, scanning tunneling microscopy/spectroscopy, and density functional theory calculations. We demonstrate that 3 × 3 charge-density-wave (CDW) order persists despite distinct changes in the low energy electronic structure highlighted by the reduction in the number of bands crossing the Fermi energy and the corresponding modification of Fermi surface topology. Enhanced spin-orbit coupling and lattice distortion in the single-layer play a crucial role in the formation of CDW order. Our findings provide a deeper understanding of the nature of CDW order in the two-dimensional limit.
Di Bernardo, A; Millo, O; Barbone, M; Alpern, H; Kalcheim, Y; Sassi, U; Ott, A K; De Fazio, D; Yoon, D; Amado, M; Ferrari, A C; Linder, J; Robinson, J W A
2017-01-19
Electron pairing in the vast majority of superconductors follows the Bardeen-Cooper-Schrieffer theory of superconductivity, which describes the condensation of electrons into pairs with antiparallel spins in a singlet state with an s-wave symmetry. Unconventional superconductivity was predicted in single-layer graphene (SLG), with the electrons pairing with a p-wave or chiral d-wave symmetry, depending on the position of the Fermi energy with respect to the Dirac point. By placing SLG on an electron-doped (non-chiral) d-wave superconductor and performing local scanning tunnelling microscopy and spectroscopy, here we show evidence for a p-wave triggered superconducting density of states in SLG. The realization of unconventional superconductivity in SLG offers an exciting new route for the development of p-wave superconductivity using two-dimensional materials with transition temperatures above 4.2 K.
Laboratory Measurements of Electrostatic Solitary Structures Generated by Beam Injection
International Nuclear Information System (INIS)
Lefebvre, Bertrand; Chen, Li-Jen; Gekelman, Walter; Pribyl, Patrick; Vincena, Stephen; Kintner, Paul; Pickett, Jolene; Chiang, Franklin; Judy, Jack
2010-01-01
Electrostatic solitary structures are generated by injection of a suprathermal electron beam parallel to the magnetic field in a laboratory plasma. Electric microprobes with tips smaller than the Debye length (λ De ) enabled the measurement of positive potential pulses with half-widths 4 to 25λ De and velocities 1 to 3 times the background electron thermal speed. Nonlinear wave packets of similar velocities and scales are also observed, indicating that the two descend from the same mode which is consistent with the electrostatic whistler mode and result from an instability likely to be driven by field-aligned currents.
Diagnosis, treatment, and response assessment in solitary plasmacytoma
DEFF Research Database (Denmark)
Caers, J; Paiva, B; Zamagni, E
2018-01-01
Solitary plasmacytoma is an infrequent form of plasma cell dyscrasia that presents as a single mass of monoclonal plasma cells, located either extramedullary or intraosseous. In some patients, a bone marrow aspiration can detect a low monoclonal plasma cell infiltration which indicates a high ris......, but studies exploring the potential benefit of systemic therapies for high-risk patients are urgently needed. In this review, a panel of expert European hematologists updates the recommendations on the diagnosis and management of patients with solitary plasmacytoma....... of early progression to an overt myeloma disease. Before treatment initiation, whole body positron emission tomography-computed tomography or magnetic resonance imaging should be performed to exclude the presence of additional malignant lesions. For decades, treatment has been based on high-dose radiation...
Numerical simulation of tsunami-scale wave boundary layers
DEFF Research Database (Denmark)
Williams, Isaac A.; Fuhrman, David R.
2016-01-01
This paper presents a numerical study of the boundary layer flow and properties induced by tsunami-scalewaves. For this purpose, an existing one-dimensional vertical (1DV) boundary layer model, based on the horizontal component of the incompressible Reynolds-averaged Navier–Stokes (RANS) equations...... demonstrating the ability to reproduce accurate velocity profiles, turbulence, and bed shear stresses on both smooth and rough beds.The validated model is then employed for the study of transient wave boundary layers at full tsunami scales,covering a wide and realistic geophysical range in terms of the flow...... duration, bottom roughness, and associated Reynolds numbers. For this purpose, three different “synthetic” (idealised) tsunami wave descriptions are considered i.e., invoking: (1) single wave (solitary-like, but with independent period and wave height),(2) sinusoidal, and (3) N-wave descriptions. The flow...
Ouyang, Wei; Mao, Weijian
2018-03-01
An asymptotic quadratic true-amplitude inversion method for isotropic elastic P waves is proposed to invert medium parameters. The multicomponent P-wave scattered wavefield is computed based on a forward relationship using second-order Born approximation and corresponding high-frequency ray theoretical methods. Within the local double scattering mechanism, the P-wave transmission factors are elaborately calculated, which results in the radiation pattern for P-waves scattering being a quadratic combination of the density and Lamé's moduli perturbation parameters. We further express the elastic P-wave scattered wavefield in a form of generalized Radon transform (GRT). After introducing classical backprojection operators, we obtain an approximate solution of the inverse problem by solving a quadratic non-linear system. Numerical tests with synthetic data computed by finite-differences scheme demonstrate that our quadratic inversion can accurately invert perturbation parameters for strong perturbations, compared with the P-wave single-scattering linear inversion method. Although our inversion strategy here is only syncretized with P-wave scattering, it can be extended to invert multicomponent elastic data containing both P-wave and S-wave information.
Hooks, Daniel E.; Ramos, Kyle J.; Martinez, A. Richard
2006-07-01
Plate impact experiments were performed on oriented single crystals of the energetic material cyclotrimethylene trinitramine (RDX). The experiments were performed to determine the anisotropic dynamic yield point for the RDX crystal, as well as to provide data for continuum modeling efforts. Impact was on the (111), (210), and (100) planes to access 3, 2, and 0 slip systems, respectively. Velocity history profiles were measured using Doppler interferometry. Impacts on the (210) plane resulted in nominally conventional results, with distinct elastic and plastic waves, stress relaxation, elastic precursor decay, and increasing wave separation with propagation distance. Velocity profiles from impacts on the (111) plane had no discernable precursor, although an inflection seen in the thicker samples might be the nearly overdriven elastic wave. Wave arrival times signaled a slower elastic wave speed in the (111) profiles. Several unexpected features were observed in the elastic precursor of the profiles from impacts on the (100) plane. Up to three distinct step features were resolved in these profiles in the region of the elastic precursor; these features are not understood. In preparing samples for these experiments, it was noted that the (100) crystal slabs were exceptionally brittle. Wave speeds determined from the shock experiments were consistent with both pulse-echo wave speed measurements and wave speeds calculated from the measured elastic tensor. The elastic limit, as indicated by the peak of the leading wave, was relatively isotropic.
Management of a solitary thyroid nodule
International Nuclear Information System (INIS)
Rao, R.S.
1999-01-01
Solitary nodule in the thyroid is a common clinical entity. A careful clinical assessment is the crucial first step in deciding the modality of treatment. The only worthwhile investigation is FNAC. Other investigations are done merely for the sake of a complete academic work up and can usually be dispensed with in most of the cases. Not every solitary nodule requires surgery. The optimum surgery for a solitary nodule is a total lobectomy. The specimen should be subjected to histological examination before recommending further treatment
Single-drop liquid phase microextraction accelerated by surface acoustic wave.
Zhang, Anliang; Zha, Yan
2013-03-01
A single-drop liquid phase microextraction method is presented, in which surface acoustic wave (SAW) is used for accelerating extraction speed. A pair of interdigital transducers with 27.5 MHz center frequency is fabricated on a 128° yx-LiNbO3 substrate. A radio frequency signal is applied to one of interdigital transducers to excite SAW. Plastic straw is filled with PDMS, leaving 1 mL for holding sample solution. Plastic straw with sample solution droplet is then dipping into extractant, into which SAW is radiated. Mass transportation from sample solution to extractant drop is accelerated due to acoustic streaming, and extraction time is decreased. An ionic liquid and an acid green-25 solution are used for extraction experiments. Results show that the extraction process is almost finished within 2 min, and extraction speed is increased with radio frequency signal power. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Directory of Open Access Journals (Sweden)
Ilhan Özgen
2017-10-01
Full Text Available In urban flood modeling, so-called porosity shallow water equations (PSWEs, which conceptually account for unresolved structures, e.g., buildings, are a promising approach to addressing high CPU times associated with state-of-the-art explicit numerical methods. The PSWE can be formulated with a single porosity term, referred to as the single porosity shallow water model (SP model, which accounts for both the reduced storage in the cell and the reduced conveyance, or with two porosity terms: one accounting for the reduced storage in the cell and another accounting for the reduced conveyance. The latter form is referred to as an integral or anisotropic porosity shallow water model (AP model. The aim of this study was to analyze the differences in wave propagation speeds of the SP model and the AP model and the implications of numerical model results. First, augmented Roe-type solutions were used to assess the influence of the source terms appearing in both models. It is shown that different source terms have different influences on the stability of the models. Second, four computational test cases were presented and the numerical models were compared. It is observed in the eigenvalue-based analysis as well as in the computational test cases that the models converge if the conveyance porosity in the AP model is close to the storage porosity. If the porosity values differ significantly, the AP model yields different wave propagation speeds and numerical fluxes from those of the BP model. In this study, the ratio between the conveyance and storage porosities was determined to be the most significant parameter.
Li, Long; Zhou, Xiaoxiao
2018-03-23
In this paper, a mechanically reconfigurable circular array with single-arm spiral antennas (SASAs) is designed, fabricated, and experimentally demonstrated to generate broadband circularly polarized orbital angular momentum (OAM) vortex waves in radio frequency domain. With the symmetrical and broadband properties of single-arm spiral antennas, the vortex waves with different OAM modes can be mechanically reconfigurable generated in a wide band from 3.4 GHz to 4.7 GHz. The prototype of the circular array is proposed, conducted, and fabricated to validate the theoretical analysis. The simulated and experimental results verify that different OAM modes can be effectively generated by rotating the spiral arms of single-arm spiral antennas with corresponding degrees, which greatly simplify the feeding network. The proposed method paves a reconfigurable way to generate multiple OAM vortex waves with spin angular momentum (SAM) in radio and microwave satellite communication applications.
Czech Academy of Sciences Publication Activity Database
Dal Moro, Giancarlo; Puzzilli, L.M.
2017-01-01
Roč. 14, č. 4 (2017), s. 431-444 ISSN 1214-9705 Institutional support: RVO:67985891 Keywords : surface wave analysis * Rayleigh wave dispersion * joint inversion * Vs30 Subject RIV: DC - Siesmology, Volcanology, Earth Structure OBOR OECD: Volcanology Impact factor: 0.699, year: 2016
Solitary Fibrous Tumor of the Uterus
Directory of Open Access Journals (Sweden)
Po-Wei Chu
2006-12-01
Conclusion: The behavior of solitary fibrous tumors arising from the uterus is difficult to evaluate; therefore, complete surgical excision featuring clear margins and comprehensive follow-up is recommended.
The cytology of giant solitary trichoepithelioma
Directory of Open Access Journals (Sweden)
Krishnamurthy Jayashree
2010-01-01
Full Text Available Giant solitary trichoepithelioma (GST is a rare trichogenic tumor, which may present as a pigmented lesion. An 80-year-old man was diagnosed to have giant solitary trichoepithelioma on fine-needle aspiration cytology. The cytological findings represented the histological features. The recognition of GST is important because of its close resemblance to basal cell carcinoma and other skin adnexal tumors - clinically, cytologically and histologically.
Solitary sternal lesions in breast cancer
International Nuclear Information System (INIS)
Morales, R.; Cano, R.; Mendoza, G.; Guzman, C.; Cotrina, M.; Aguilar, C.
1993-01-01
In a retrospective review of bone scans performed in 1740 patients with breast cancer from January 1988 to April 1993, twenty had a solitary sternal lesion. Etiology was found correlating this finding with pathology, x-rays and/or final outcome. Nineteen lesions were due to metastases and one to infection. This experience suggests that solitary sternal lesions in breast cancer patients are uncommon and are most frequently (95%) associated with malignant etiology. (Authors). 10 refs., 2 figs
Giant solitary fibrous tumour of the liver
Directory of Open Access Journals (Sweden)
Eggermont Alexander MM
2006-11-01
Full Text Available Abstract Background Solitary fibrous tumour (SFT is an uncommon mesenchymal neoplasm that most frequently affects the pleura, although it has been reported with increasing frequency in various other sites such as in the peritoneum, pericardium and in non-serosal sites such as lung parenchyma, upper respiratory tract, orbit, thyroid, parotid gland, or thymus. Liver parenchyma is rarely affected. Clinically, SFTs cause symptoms after having reached a certain size or when vital structures are involved. In recent years, SFTs are more often identified and distinguished from other tumours with a similar appearance due to the availability of characteristic immunohistochemical markers. Case presentation In this manuscript we report the case of a large tumour of the liver, which was histologically diagnosed as a SFT, and showed involvement of a single hepatic segment. Because of the patient's presentation and clinical course, it may represent a radiation-induced lesion. Conclusion When a SFT has been diagnosed, surgery is the treatment of choice. The small number of patients with a SFT of the liver and its unknown natural behaviour creates the need to a careful registration and follow-up of all identified cases
Fourier transforms of single-particle wave functions in cylindrical coordinates
International Nuclear Information System (INIS)
Rizea, M.; Carjan, N.
2016-01-01
A formalism and the corresponding numerical procedures that calculate the Fourier transform of a single-particle wave function defined on a grid of cylindrical (ρ, z) coordinates is presented. Single-particle states in spherical and deformed nuclei have been chosen in view of future applications in the field of nuclear reactions. Bidimensional plots of the probability that the nucleon's momentum has a given value K = √(k ρ 2 +k z 2 ) are produced and from them the K -distributions are deduced. Three potentials have been investigated: (a) a sharp surface spherical well (i.e., of constant depth), (b) a spherical Woods-Saxon potential (i.e., diffuse surface) and (c) a deformed potential of Woods-Saxon type. In the first case the momenta are as well defined as allowed by the uncertainty principle. Depending on the state, their distributions have up to three separated peaks as a consequence of the up to three circular ridges of the bidimensional probabilities plots. In the second case the diffuseness allows very low momenta to be always populated thus creating tails towards the origin (K = 0). The peaks are still present but not well separated. In the third case the deformation transforms the above mentioned circular ridges into ellipses thus spreading the K-values along them. As a consequence the K-distributions have only one broad peak. (orig.)
Resolving Difficulties of a Single-Channel Partial-Wave Analysis
Hunt, Brian; Manley, D. Mark
2016-03-01
The goal of our research is to determine better the properties of nucleon resonances using techniques of a global multichannel partial-wave analysis. Currently, many predicted resonances have not been found, while the properties of several known resonances are relatively uncertain. To resolve these issues, one must analyze many different reactions in a multichannel fit. Other groups generally approach this problem by generating an energy-dependent fit from the start. This is a fit where all channels are analyzed together. The method is powerful, but due to the complex nature of resonances, certain model-dependent assumptions have to be introduced from the start. The current work tries to resolve these issues by first generating single-energy solutions in which experimental data are analyzed in narrow energy bins. The single-energy solutions can then be used to constrain the energy-dependent solution in a comparatively unbiased manner. Our work focuses on adding three new single-energy solutions into the global fit. These reactions are γp --> ηp , γn --> ηn , and γp -->K+ Λ . During this talk, I will discuss the difficulties of this approach, our methods to overcome these difficulties, and a few preliminary results. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Medium Energy Nuclear Physics, under Award Nos. DE-FG02-01ER41194 and DE-SC0014323 and by the Kent State University Department of Physics.
Kongnun, Weerapon; Silapan, Phamorn
2013-01-01
The article presents a current-mode full-wave rectifier employing multiple output current follower transconductance amplifier (MO-CFTA). The both circuits description is very simple, it merely comprises only single MO-CFTA, without external passive element. In addition, the magnitude and direction of output currents can be controlled via electronically method. Furthermore, the outputs are independent of the thermal voltage (VT). The performances of the proposed circuits are investigated thro...
DEFF Research Database (Denmark)
Ibsen, Lars Bo
2008-01-01
Estimates for the amount of potential wave energy in the world range from 1-10 TW. The World Energy Council estimates that a potential 2TW of energy is available from the world’s oceans, which is the equivalent of twice the world’s electricity production. Whilst the recoverable resource is many...
Energy Technology Data Exchange (ETDEWEB)
Himpel, Michael, E-mail: himpel@physik.uni-greifswald.de; Killer, Carsten; Melzer, André [Institute of Physics, Ernst-Moritz-Arndt-University, 17489 Greifswald (Germany); Bockwoldt, Tim; Piel, Alexander [IEAP, Christian-Albrechts-Universität Kiel, D-24098 Kiel (Germany); Ole Menzel, Kristoffer [ABB Switzerland Ltd, Corporate Research Center, 5405 Dättwil (Switzerland)
2014-03-15
Experiments on dust-density waves have been performed in dusty plasmas under the microgravity conditions of parabolic flights. Three-dimensional measurements of a dust density wave on a single particle level are presented. The dust particles have been tracked for many oscillation periods. A Hilbert analysis is applied to obtain trajectory parameters such as oscillation amplitude and three-dimensional velocity amplitude. While the transverse motion is found to be thermal, the velocity distribution in wave propagation direction can be explained by harmonic oscillations with added Gaussian (thermal) noise. Additionally, it is shown that the wave properties can be reconstructed by means of a pseudo-stroboscopic approach. Finally, the energy dissipation mechanism from the kinetic oscillation energy to thermal motion is discussed and presented using phase-resolved analysis.
International Nuclear Information System (INIS)
Sharma, Sarveshwar; Turner, M.M.
2013-01-01
In low-pressure capacitive discharges, stochastic heating is the dominant electron heating mechanism which occurs due to the momentum transfer from the oscillating electron sheath edge to electrons. The existence of waves in electron density close to the sheath edge was firstly reported in literature but a comprehensive analysis of their nature has not been discussed. The evidence of wave emission with a frequency near to electron plasma frequency adjacent the sheath territory in case of collisionless plasma in single frequency capacitive discharges was detailed investigated by S Sharma et al. Here the wave properties have been studied by varying the current density amplitude J0 for a constant Radio-Frequency (RF), 27.12 MHz. The electron temperature was also constant (2.5 eV). The field reversal and ion reflection phenomena were reported. In current research work, these waves are studied by varying the frequency of applied RF and keeping other parameters constant. The wave amplitude changes with the frequency of applied RF and the presence of strong field reversal region also observed. The wave properties are also studied by varying the electron temperature Te for applied frequency 27.12 MHz by keeping all other controlling parameters constant. At low values of electron temperature i.e. ∼ 2 eV the strong field reversal emerges. The wave amplitude is also varies by changing electron temperature. (author)
Demonstration and study of the dispersion of water waves with a computer-controlled ripple tank
Ströbel, Bernhard
2011-06-01
The design of a ripple tank built in an undergraduate student project is described. Water waves are excited acoustically using computer programmable wave shapes. The projected wave patterns are recorded with a video camera and analyzed quantitatively. From the propagation of wave packets in distilled water at three different depths, the phase and group velocities are measured in the frequency range from 2 to 50 Hz. Good agreement with theory is found. The propagation of wave trains of different shapes is recorded and explained on the basis of the stationary phase approximation. Various types of precursors are detected. For a depth slightly above the critical depth and thus nearly dispersion-free, the solitary-like propagation of a single pulse is observed. In shallow water, the compression of a chirped pulse is demonstrated. Circular waves produced by falling water drops are recorded and analyzed.
Compact Single-Layer Traveling-Wave Antenna DesignUsing Metamaterial Transmission Lines
Alibakhshikenari, Mohammad; Virdee, Bal Singh; Limiti, Ernesto
2017-12-01
This paper presents a single-layer traveling-wave antenna (TWA) that is based on composite right/left-handed (CRLH)-metamaterial (MTM) transmission line (TL) structure, which is implemented by using a combination of interdigital capacitors and dual-spiral inductive slots. By embedding dual-spiral inductive slots inside the CRLH MTM-TL results in a compact TWA. Dimensions of the proposed CRLH MTM-TL TWA is 21.5 × 30.0 mm2 or 0.372λ0 × 0.520λ0 at 5.2 GHz (center frequency). The fabricated TWA operates over 1.8-8.6 GHz with a fractional bandwidth greater than 120%, and it exhibits a peak gain and radiation efficiency of 4.2 dBi and 81%, respectively, at 5 GHz. By avoiding the use of lumped components, via-holes or defected ground structures, the proposed TWA design is economic for mass production as well as easy to integrate with wireless communication systems.
Control of single photon emitters in semiconductor nanowires by surface acoustic waves
Lazić, S.; Hernández-Mínguez, A.; Santos, P. V.
2017-08-01
We report on an experimental study into the effects of surface acoustic waves on the optical emission of dot-in-a-nanowire heterostructures in III-V material systems. Under direct optical excitation, the excitonic energy levels in III-nitride dot-in-a-nanowire heterostructures oscillate at the acoustic frequency, producing a characteristic splitting of the emission lines in the time-integrated photoluminescence spectra. This acoustically induced periodic tuning of the excitonic transition energies is combined with spectral detection filtering and employed as a tool to regulate the temporal output of anti-bunched photons emitted from these nanowire quantum dots. In addition, the acoustic transport of electrons and holes along a III-arsenide nanowire injects the electric charges into an ensemble of quantum dot-like recombination centers that are spatially separated from the optical excitation area. The acoustic population and depopulation mechanism determines the number of carrier recombination events taking place simultaneously in the ensemble, thus allowing control of the anti-bunching degree of the emitted photons. The results presented are relevant for the dynamic control of single photon emission in III-V semiconductor heterostructures.
Single-chain statistics and the upper wave-vector cutoff in polymer blends
International Nuclear Information System (INIS)
Holyst, R.; Vilgis, T.A.
1994-01-01
We derive the equation for the single-chain correlation function in polymer blends. The chains in the incompressible blend have a radius of gyration smaller than the radius of gyration for ideal chains. The chains shrink progressively as we approach the critical temperature T c . The correction responsible for shrinking is proportional to 1/ √N , where N is the polymerization index. At T=T c and for N=1000, the size of the chain has been estimated to be 10% smaller than the size of the ideal coil. The estimate relies on the appropriate cutoff. In the limit of N→∞ the chains approach the random walk limit. Additionally, we propose in this paper a self-consistent determination of the radius of gyration and the upper wave-vector cutoff. Our model is free from any divergences such as were encountered in the previous mean-field studies; we make an estimate of the chain size at the true critical temperature and not the mean-field one
Self-sustained hysteretic motional oscillations of a single atom pumped by a laser standing wave
Kaplan, A E
1999-01-01
Summary form only given. Self-sustained oscillations/oscillators (SSO), man-made or naturally occurring, are some of the most universal phenomena. The common feature of all SSO is the so called positive feedback, which overcomes the damping by properly controlling the energy supply (pumping) from the outside source during the cycle of oscillations. Usually, the zero steady-state point of the system is unstable, and the oscillations grow up till they reach a stable limit cycle. The common quality of the resulting SSO is their well defined amplitude (the so called classical squeezing) at the expense of undetermined phase of oscillations. All the "mechanical motion" SSO known so far, were based on macro- systems, while it would be of great importance to develop a microscopic SS-oscillator based on a single particle (atom or ion), which would enable us to control the SSO mode from classical to quantum limits. The effect proposed is based on the interaction of a standing laser wave with an atom moving in along the...
Wang, Zhenqing; Tang, Xiaojun; Lv, Hongqing; Shi, Jianqiang
2014-01-01
By using a high-order accurate finite difference scheme, direct numerical simulation of hypersonic flow over an 8° half-wedge-angle blunt wedge under freestream single-frequency entropy disturbance is conducted; the generation and the temporal and spatial nonlinear evolution of boundary layer disturbance waves are investigated. Results show that, under the freestream single-frequency entropy disturbance, the entropy state of boundary layer is changed sharply and the disturbance waves within a certain frequency range are induced in the boundary layer. Furthermore, the amplitudes of disturbance waves in the period phase are larger than that in the response phase and ablation phase and the frequency range in the boundary layer in the period phase is narrower than that in these two phases. In addition, the mode competition, dominant mode transformation, and disturbance energy transfer exist among different modes both in temporal and in spatial evolution. The mode competition changes the characteristics of nonlinear evolution of the unstable waves in the boundary layer. The development of the most unstable mode along streamwise relies more on the motivation of disturbance waves in the upstream than that of other modes on this motivation.
Solitary restriction endonucleases in prokaryotic genomes.
Ershova, Anna S; Karyagina, Anna S; Vasiliev, Mikhail O; Lyashchuk, Alexander M; Lunin, Vladimir G; Spirin, Sergey A; Alexeevski, Andrei V
2012-11-01
Prokaryotic restriction-modification (R-M) systems defend the host cell from the invasion of a foreign DNA. They comprise two enzymatic activities: specific DNA cleavage activity and DNA methylation activity preventing cleavage. Typically, these activities are provided by two separate enzymes: a DNA methyltransferase (MTase) and a restriction endonuclease (RE). In the absence of a corresponding MTase, an RE of Type II R-M system is highly toxic for the cell. Genes of the R-M system are linked in the genome in the vast majority of annotated cases. There are only a few reported cases in which the genes of MTase and RE from one R-M system are not linked. Nevertheless, a few hundreds solitary RE genes are present in the Restriction Enzyme Database (http://rebase.neb.com) annotations. Using the comparative genomic approach, we analysed 272 solitary RE genes. For 57 solitary RE genes we predicted corresponding MTase genes located distantly in a genome. Of the 272 solitary RE genes, 99 are likely to be fragments of RE genes. Various explanations for the existence of the remaining 116 solitary RE genes are also discussed.
Dust acoustic solitary and shock excitations in a Thomas-Fermi magnetoplasma
International Nuclear Information System (INIS)
Rahim, Z.; Qamar, A.; Ali, S.
2014-01-01
The linear and nonlinear properties of dust-acoustic waves are investigated in a collisionless Thomas-Fermi magnetoplasma, whose constituents are electrons, ions, and negatively charged dust particles. At dust time scale, the electron and ion number densities follow the Thomas-Fermi distribution, whereas the dust component is described by the classical fluid equations. A linear dispersion relation is analyzed to show that the wave frequencies associated with the upper and lower modes are enhanced with the variation of dust concentration. The effect of the latter is seen more strongly on the upper mode as compared to the lower mode. For nonlinear analysis, we obtain magnetized Korteweg-de Vries (KdV) and Zakharov-Kuznetsov (ZK) equations involving the dust-acoustic solitary waves in the framework of reductive perturbation technique. Furthermore, the shock wave excitations are also studied by allowing dissipation effects in the model, leading to the Korteweg-de Vries-Burgers (KdVB) and ZKB equations. The analysis reveals that the dust-acoustic solitary and shock excitations in a Thomas-Fermi plasma are strongly influenced by the plasma parameters, e.g., dust concentration, dust temperature, obliqueness, magnetic field strength, and dust fluid viscosity. The present results should be important for understanding the solitary and shock excitations in the environments of white dwarfs or supernova, where dust particles can exist
The primary Maxillary Central Incisor in the Solitary Median Maxillary Central Incisor syndrome
DEFF Research Database (Denmark)
Kjaer, I; Balslev-Olesen, M
2012-01-01
Solitary Median Maxillary Central Incisor (SMMCI) is a developmental anomaly in the permanent dentition with one single central incisor in the maxilla, positioned exactly in the midline. This condition has been associated with extra- and intraoral malformations in the frontonasal segment of the c...
Solitary neurofibroma of eyelid masquerading as chalazion.
Chen, Nancy; Hsu, Yung-Hsiang; Lee, Yuan-Chieh
2017-01-01
Neurofibroma, a benign peripheral nerve sheath tumor, usually appears together with café-au-lait spots, iris nodules, and other tumors within the scope of neurofibromatosis von Recklinghausen type 1 tumors. A solitary neurofibroma of the eyelid is relatively rare. In this case report, we present a 39-year-old woman who had a lesion on the eyelid crease, previously treated as a chalazion. Due to persistent wound crusting, the lesion was excised above the tarsus. Pathological examination revealed a solitary neurofibroma. The patient did not have other clinical symptoms of neurofibromatosis, and there was no recurrence of the nodule during the 1-year follow-up.
Solitary gastric melanotic schwannoma: sonographic findings.
Chen, Yang-Yuan; Yen, Hsu-Heng; Soon, Maw-Soan
2007-01-01
Solitary gastric schwannoma is rare, and solitary melanotic schwannoma is even rarer, posing a dilemma in diagnosis and treatment. We report the case of a 69-year-old woman with gastric melanotic schwannoma who presented with nausea, vomiting, and abdominal pain. Abdominal sonographic examination revealed a 5-cm hypoechoic mass in the epigastric area that was confirmed to be a gastric submucosal tumor on endoscopic examination. The diagnosis of melanotic schwannoma was confirmed via sonographically guided percutaneous core biopsy. The tumor was resected, and no recurrence has occurred in a 3-year follow-up.
Solitary extramedullary plasmacytoma of the sinonasal region.
Hazarika, Produl; Balakrishnan, R; Singh, Rohit; Pujary, Kailesh; Aziz, Benazim
2011-07-01
Less than 10% of the patients with plasma cell neoplasms present with a solitary plasmacytoma. Though the nasal cavity is a common extramedullary site, the occurrence is extremely rare. Two cases of solitary extramedullary plasmacytoma of the sinonasal region are reported. The first of which is sinonasal plasmacytoma with concomitant HIV, an association that has been reported rarely in literature to date and is matter of much debate. In the second case report, we present an instance of surgical excision of the tumor using KTP 532 laser. The diagnosis was established using immunohistochemical techniques and multiple myeloma workups were negative in all cases.
Solitary eccrine syringofibroadenoma--Case Report.
Bottino, Caroline Bertolini; Guimarães, Tais Ferreira; Gomes, Flávio Rezende; D'Acri, Antonio Macedo; Lima, Ricardo Barbosa; Martins, Carlos José
2015-01-01
Eccrine syringofibroadenoma is a rare benign adnexal neoplasm derived from cells of the acrosyringium of eccrine sweat glands. ESFA usually manifests as a solitary nodule on the extremities of elderly patients, but it may also present as papules, nodules or plaques. Its clinical appearance is nonspecific and malignant neoplasms should be considered in the differential diagnosis. However, histopathological findings are typical. The main treatment is surgical excision. In order to illustrate a typical presentation of the tumor, we report a case of solitary eccrine syringofibroadenoma, including the surgical treatment used and its result.
Continuous-wave, singly resonant parametric oscillator-based mid-infrared optical vortex source.
Aadhi, A; Sharma, Varun; Singh, R P; Samanta, G K
2017-09-15
We report on a high-power, continuous-wave source of optical vortices tunable in the mid-infrared (mid-IR) wavelength range. Using the orbital angular momentum (OAM) conservation of the parametric processes and the threshold conditions of the cavity modes of the singly resonant optical parametric oscillator (SRO), we have transferred the OAM of the pump beam at the near-infrared wavelength to the idler beam tunable in the mid-IR. Pumped with a vortex beam of order l p =1 at 1064 nm, the SRO, configured in a four curved mirror-based ring cavity with a 50 mm long MgO-doped periodically poled LiNbO 3 crystal, produces an idler beam with an output power in excess of 2 W in a vortex spatial profile with the order l i =1, tunable across 2217-3574 nm and corresponding signal beam in Gaussian intensity distribution across 1515-2046 nm. For pump vortices of the order l p =1 and 2, and a power of 22 W, the SRO produces idler vortices of the same order as that of the pump beam with a maximum power of 5.23 and 2.3 W, corresponding to near-IR to mid-IR vortex conversion efficiency of 23.8% and 10.4%, respectively. The idler vortex beam has a spectral width, and a passive rms power stability of 101 MHz and 4.9% over 2 h, respectively.
DEFF Research Database (Denmark)
Utko, Pawel; Hansen, Jørn Bindslev; Lindelof, Poul Erik
2007-01-01
We have investigated the response of the acoustoelectric-current driven by a surface-acoustic wave through a quantum point contact in the closed-channel regime. Under proper conditions, the current develops plateaus at integer multiples of ef when the frequency f of the surface-acoustic wave...... or the gate voltage V-g of the point contact is varied. A pronounced 1.1 MHz beat period of the current indicates that the interference of the surface-acoustic wave with reflected waves matters. This is supported by the results obtained after a second independent beam of surface-acoustic wave was added......, though at different current values, as if they were superposed on each other. Their presence could result from two independent quantization mechanisms for the acoustoelectric-current. We point out that short potential barriers determining the properties of our nominally long constrictions could lead...
Numerical Solution of the Modified Equal Width Wave Equation
Directory of Open Access Journals (Sweden)
Seydi Battal Gazi Karakoç
2012-01-01
Full Text Available Numerical solution of the modified equal width wave equation is obtained by using lumped Galerkin method based on cubic B-spline finite element method. Solitary wave motion and interaction of two solitary waves are studied using the proposed method. Accuracy of the proposed method is discussed by computing the numerical conserved laws 2 and ∞ error norms. The numerical results are found in good agreement with exact solution. A linear stability analysis of the scheme is also investigated.
Jacobian elliptic wave solutions in an anharmonic molecular crystal model
International Nuclear Information System (INIS)
Teh, C.G.R.; Lee, B.S.; Koo, W.K.
1997-07-01
Explicit Jacobian elliptic wave solutions are found in the anharmonic molecular crystal model for both the continuum limit and discrete modes. This class of wave solutions include the famous pulse-like and kink-like solitary modes. We would also like to report on the existence of some highly discrete staggered solitary wave modes not found in the continuum limit. (author). 9 refs, 1 fig
DEFF Research Database (Denmark)
Koefoed, Jacob Gade; Friis, Søren Michael Mørk; Christensen, Jesper Bjerge
2017-01-01
We model the spectral quantum-mechanical purity of heralded single photons from a photon-pair source based on nondegenerate spontaneous four-wave mixing taking the impact of distributed dispersion fluctuations into account. The considered photon-pair-generation scheme utilizes pump-pulse walk......-off to produce pure heralded photons and phase matching is achieved through the dispersion properties of distinct spatial modes in a few-mode silica step-index fiber. We show that fiber-core-radius fluctuations in general severely impact the single-photon purity. Furthermore, by optimizing the fiber design we...... frequency. (C) 2017 Optical Society of America...
Formation and Coalescence of Electron Solitary Holes
DEFF Research Database (Denmark)
Saeki, K.; Michelsen, Poul; Pécseli, H. L.
1979-01-01
Electron solitary holes were observed in a magnetized collisionless plasma. These holes were identified as Bernstein-Green-Kruskal equilibria, thus being purely kinetic phenomena. The electron hole does not damp even though its velocity is close to the electron thermal velocity. Two holes attract...
Electrophysiological effects of the solitary bee "Anthophora
African Journals Online (AJOL)
Department of Zoology, Faculty of Science, Suez Canal University, Ismailia, Egypt. ABSTRACT. Effects of the crude venom of the solitary bee (Anthophora pauperata) on cardiac, skeletal and smooth muscles were studied to reveal the mechanism of action of this venom. The main toxic effects on the ECG of isolated toads'.
Peptide Toxins in Solitary Wasp Venoms
Directory of Open Access Journals (Sweden)
Katsuhiro Konno
2016-04-01
Full Text Available Solitary wasps paralyze insects or spiders with stinging venom and feed the paralyzed preys to their larva. Accordingly, the venoms should contain a variety of constituents acting on nervous systems. However, only a few solitary wasp venoms have been chemically studied despite thousands of species inhabiting the planet. We have surveyed bioactive substances in solitary wasp venoms found in Japan and discovered a variety of novel bioactive peptides. Pompilidotoxins (PMTXs, in the venoms of the pompilid wasps Anoplius samariensis and Batozonellus maculifrons, are small peptides consisting of 13 amino acids without a disulfide bond. PMTXs slowed Na+ channel inactivation, in particular against neuronal type Na+ channels, and were rather selective to the Nav1.6 channel. Mastoparan-like cytolytic and antimicrobial peptides are the major components of eumenine wasp venoms. They are rich in hydrophobic and basic amino acids, adopting a α-helical secondary structure, and showing mast cell degranulating, antimicrobial and hemolytic activities. The venom of the spider wasp Cyphononyx fulvognathus contained four bradykinin-related peptides. They are hyperalgesic and, dependent on the structure, differently associated with B1 or B2 receptors. Further survey led to the isolation of leucomyosuppressin-like FMRFamide peptides from the venoms of the digger wasps Sphex argentatus and Isodontia harmandi. These results of peptide toxins in solitary wasp venoms from our studies are summarized.
Histoplasmosis presenting with solitary pulmonary nodule: Two ...
African Journals Online (AJOL)
Pulmonary histoplasmosis is a granulomatous disease, whose diagnosis is not always easy, as it may simulate metastatic lesions due to similar radiographic findings. We herein report two cases of histoplasmosis with solitary pulmonary nodule in asymptomatic patients with histories of cancer surgeries, whose diagnoses ...
Position of solitary thyroid nodules by gammagraphy
International Nuclear Information System (INIS)
Basteris M, J.; Gomez D, R.
2007-01-01
In this work it is presented which it is the position more frequent of the solitary thyroid nodules. It was used the method of retrospective longitudinal observational investigation in 125 patients that went to the laboratory for realization of detection of thyroid nodules in the years 2004 and 2005 through gammagraphy. (Author)
Clinical implications of the solitary functioning kidney
Westland, Rik; Schreuder, Michiel F.; van Goudoever, Johannes B.; Sanna-Cherchi, Simone; van Wijk, Joanna A. E.
2014-01-01
Congenital anomalies of the kidney and urinary tract are the major cause of ESRD in childhood. Children with a solitary functioning kidney form an important subgroup of congenital anomalies of the kidney and urinary tract patients, and a significant fraction of these children is at risk for
The solitary sellar plasmacytoma: a diagnostic challenge
DEFF Research Database (Denmark)
Soejbjerg, Anne; Dyve, Suzan; Baerentzen, Steen
2016-01-01
UNLABELLED: Solitary sellar plasmacytomas are exceedingly rare and difficult to distinguish from other pituitary tumors. We report a case of a 62-year-old woman presenting with blurred vision of the right eye and tenderness of the right temporal region, which was interpreted as temporal arteritis...
Non-linear high-frequency waves in the magnetosphere
Indian Academy of Sciences (India)
forms of solitary bipolar electric field pulses which are called electrostatic solitary waves. (ESW) [1]. Karovsky et al [5] have used a BGK analysis to theoretically describe the high-frequency. ESW. Using counter-streaming electron and ion beams in a computer simulation experi- ment, Omura et al [6] have shown that the ...
DEFF Research Database (Denmark)
Orozco-Santillán, Arturo; Ruiz-Boullosa, Ricardo; Cutanda Henríquez, Vicente
2007-01-01
It is well known that acoustic waves exert forces on a boundary with which they interact; these forces can be so intense that they can compensate for the weight of small objects up to a few grams. In this way, it is possible to maintain solid or liquid samples levitating in a fluid, avoiding the ...... are highly damped. This dependence of the instabilities on the amplitude of the driving acoustic wave, however, cannot be described with the existing theory....
Nonlinear waves in solar plasmas - a review
International Nuclear Information System (INIS)
Ballai, I
2006-01-01
Nonlinearity is a direct consequence of large scale dynamics in the solar plasmas. When nonlinear steepening of waves is balanced by dispersion, solitary waves are generated. In the vicinity of resonances, waves can steepen into nonlinear waves influencing the efficiency of energy deposition. Here we review recent theoretical breakthroughs that have lead to a greater understanding of many aspects of nonlinear waves arising in homogeneous and inhomogeneous solar plasmas
Single molecule experiments challenge the strict wave-particle dualism of light.
Greulich, Karl Otto
2010-01-21
Single molecule techniques improve our understanding of the photon and light. If the single photon double slit experiment is performed at the "single photon limit" of a multi-atom light source, faint light pulses with more than one photon hamper the interpretation. Single molecules, quantum dots or defect centres in crystals should be used as light source. "Single photon detectors" do not meet their promise-only "photon number resolving single photon detectors" do so. Particularly, the accumulation time argument, the only safe basis for the postulate of a strictly particle like photon, has so far not yet been verified.
Single Molecule Experiments Challenge the Strict Wave-Particle Dualism of Light
Directory of Open Access Journals (Sweden)
Karl Otto Greulich
2010-01-01
Full Text Available Single molecule techniques improve our understanding of the photon and light. If the single photon double slit experiment is performed at the “single photon limit” of a multi-atom light source, faint light pulses with more than one photon hamper the interpretation. Single molecules, quantum dots or defect centres in crystals should be used as light source. “Single photon detectors” do not meet their promise―only “photon number resolving single photon detectors” do so. Particularly, the accumulation time argument, the only safe basis for the postulate of a strictly particle like photon, has so far not yet been verified.
Genova, Pietro; Brunetti, Francesco; Bequignon, Emilie; Landi, Filippo; Lizzi, Vincenzo; Esposito, Francesco; Charpy, Cecile; Calderaro, Julien; Azoulay, Daniel; de'Angelis, Nicola
2016-07-15
Solitary splenic metastases are a rare occurrence, and the nasopharyngeal carcinoma represents one of the most uncommon primary sources. The present study aimed to describe a rare case of a solitary single splenic metastasis from nasopharyngeal carcinoma and to assess the number of cases of isolated nasopharyngeal carcinoma metastases to the spleen reported in the literature. We describe the case of a 56-year-old man with a history of nasopharyngeal carcinoma and complete remission after chemo-radiotherapy. Three months after complete remission, positron emission tomography/computed tomography scan revealed a hypermetabolic splenic lesion without increased metabolic activity in other areas. After laparoscopic splenectomy, the pathology report confirmed a single splenic metastasis from undifferentiated carcinoma of the nasopharyngeal type. The postoperative period was uneventful. We also performed a systematic review of the literature using MEDLINE and Google Scholar databases. All articles reporting cases of splenic metastases from nasopharyngeal carcinoma, with or without histologic confirmation, were evaluated. The literature search yielded 15 relevant articles, which were very heterogeneous in their aims and methods and described only 25 cases of splenic metastases from nasopharyngeal carcinoma. The present review shows that solitary splenic metastases from nasopharyngeal carcinoma are a rare event, but it should be considered in patients presenting with splenic lesions at imaging and a history of primary or recurrent nasopharyngeal carcinoma. No evidence supports a negative impact of splenectomy in patients with solitary splenic metastasis from nasopharyngeal carcinoma.
International Nuclear Information System (INIS)
Zhang Zaiyun; Liu Zhenhai; Miao Xiujin; Chen Yuezhong
2011-01-01
In this Letter, we investigate the perturbed nonlinear Schroedinger's equation (NLSE) with Kerr law nonlinearity. All explicit expressions of the bounded traveling wave solutions for the equation are obtained by using the bifurcation method and qualitative theory of dynamical systems. These solutions contain bell-shaped solitary wave solutions, kink-shaped solitary wave solutions and Jacobi elliptic function periodic solutions. Moreover, we point out the region which these periodic wave solutions lie in. We present the relation between the bounded traveling wave solution and the energy level h. We find that these periodic wave solutions tend to the corresponding solitary wave solutions as h increases or decreases. Finally, for some special selections of the energy level h, it is shown that the exact periodic solutions evolute into solitary wave solution.
Enzyme molecules in solitary confinement.
Liebherr, Raphaela B; Gorris, Hans H
2014-09-12
Large arrays of homogeneous microwells each defining a femtoliter volume are a versatile platform for monitoring the substrate turnover of many individual enzyme molecules in parallel. The high degree of parallelization enables the analysis of a statistically representative enzyme population. Enclosing individual enzyme molecules in microwells does not require any surface immobilization step and enables the kinetic investigation of enzymes free in solution. This review describes various microwell array formats and explores their applications for the detection and investigation of single enzyme molecules. The development of new fabrication techniques and sensitive detection methods drives the field of single molecule enzymology. Here, we introduce recent progress in single enzyme molecule analysis in microwell arrays and discuss the challenges and opportunities.
International Nuclear Information System (INIS)
Ono, A.
2002-03-01
Anti-symmetrized molecular dynamics with quantum branching is generalized so as to allow finite time duration of the unrestricted coherent mean field propagation which is followed by the decoherence into wave packets. In this new model, the wave packet shrinking by the mean field propagation is respected as well as the diffusion, so that it predicts a one-body dynamics similar to that in mean field models. The shrinking effect is expected to change the diffusion property of nucleons in nuclear matter and the global one-body dynamics. The central 129 Xe + Sn collisions at 50 MeV/nucleon are calculated by the models with and without shrinking, and it is shown that the inclusion of the wave packet shrinking has a large effect on the multifragmentation in a big expanding system with a moderate expansion velocity. (author)
Cnoidal waves governed by the Kudryashov–Sinelshchikov equation
Energy Technology Data Exchange (ETDEWEB)
Randrüüt, Merle, E-mail: merler@cens.ioc.ee [Tallinn University of Technology, Faculty of Mechanical Engineering, Department of Mechatronics, Ehitajate tee 5, 19086 Tallinn (Estonia); Braun, Manfred [University of Duisburg–Essen, Chair of Mechanics and Robotics, Lotharstraße 1, 47057 Duisburg (Germany)
2013-10-30
The evolution equation for waves propagating in a mixture of liquid and gas bubbles as proposed by Kudryashov and Sinelshchikov allows, in a special case, the propagation of solitary waves of the sech{sup 2} type. It is shown that these waves represent the solitary limit separating two families of periodic waves. One of them consists of the same cnoidal waves that are solutions of the Korteweg–de Vries equation, while the other one does not have a corresponding counterpart. It is pointed out how the ordinary differential equations governing traveling-wave solutions of the Kudryashov–Sinelshchikov and the Korteweg–de Vries equations are related to each other.
Directory of Open Access Journals (Sweden)
Yosef London
2017-04-01
Full Text Available An opto-electronic radio-frequency oscillator that is based on forward scattering by the guided acoustic modes of a standard single-mode optical fiber is proposed and demonstrated. An optical pump wave is used to stimulate narrowband, resonant guided acoustic modes, which introduce phase modulation to a co-propagating optical probe wave. The phase modulation is converted to an intensity signal at the output of a Sagnac interferometer loop. The intensity waveform is detected, amplified, and driven back to modulate the optical pump. Oscillations are achieved at a frequency of 319 MHz, which matches the resonance of the acoustic mode that provides the largest phase modulation of the probe wave. Oscillations at the frequencies of competing acoustic modes are suppressed by at least 40 dB. The linewidth of the acoustic resonance is sufficiently narrow to provide oscillations at a single longitudinal mode of the hybrid cavity. Competing longitudinal modes are suppressed by at least 38 dB as well. Unlike other opto-electronic oscillators, no radio-frequency filtering is required within the hybrid cavity. The frequency of oscillations is entirely determined by the fiber opto-mechanics.
Arbitrary amplitude magnetosonic solitary and shock structures in spin quantum plasma
Energy Technology Data Exchange (ETDEWEB)
Sahu, Biswajit [Department of Mathematics, West Bengal State University, Barasat, Kolkata-700126 (India); Sinha, Anjana; Roychoudhury, Rajkumar; Khan, Manoranjan [Department of Instrumentation Science, Jadavpur University, Kolkata-700 032 (India)
2013-11-15
A nonlinear analysis is carried out for the arbitrary amplitude magnetosonic solitary and shock structures in spin quantum plasmas. A quantum magnetohydrodynamic model is used to describe the magnetosonic quantum plasma with the Bohm potential and the pressure like spin force for electrons. Analytical calculations are used to simplify the basic equations, which are then studied numerically. It is shown that the magnetic diffusivity is responsible for dissipation, which causes the shock-like structures rather than the soliton structures. Additionally, wave speed, Zeeman energy, and Bohm potential are found to have significant impact on the shock wave structures.
Single Peak Soliton and Periodic Cusp Wave of the Generalized Schrodinger-Boussinesq Equations
Qiao, Li-Jing; Tang, Sheng-Qiang; Zhao, Hai-Xia
2015-06-01
In this paper, we study peakon, cuspon, smooth soliton and periodic cusp wave of the generalized Schrödinger-Boussinesq equations. Based on the method of dynamical systems, the generalized Schrödinger-Boussinesq equations are shown to have new the parametric representations of peakon, cuspon, smooth soliton and periodic cusp wave solutions. Under different parametric conditions, various sufficient conditions to guarantee the existence of the above solutions are given. Supported by National Natural Science Foundation of China under Grant Nos. 11361017, 11161013 and Natural Science Foundation of Guangxi under Grant Nos. 2012GXNSFAA053003, 2013GXNSFAA019010, and Program for Innovative Research Team of Guilin University of Electronic Technology
Tahara, Tatsuki; Akamatsu, Takanori; Arai, Yasuhiko; Shimobaba, Tomoyoshi; Ito, Tomoyoshi; Kakue, Takashi
2017-11-01
We propose a novel algorithm that does not require any Fourier transform to extract multiple object waves in a single image recorded with spatial frequency-division multiplexing. Smoothing is utilized to extract the desired object-wave information from a spatially multiplexed image. Numerical and experimental results show its validity and applicability for image and Fresnel digital holography. Our investigations clarify the speeding up of both the object-wave extractions and multiple object-image reconstructions quantitatively.
Directory of Open Access Journals (Sweden)
Daniele Angerame
2012-01-01
Full Text Available The aim of the present microtomographic study was to investigate the quality of root canal filling and the voids formation in canals of extracted teeth instrumented with a simultaneous technique and filled with two different methods. Twenty-four single-rooted teeth were assigned to two experimental groups (no. = 12; canals were shaped with NiTi rotary files, irrigated with NaOCl and filled either with the single point (group 1 or the continuous wave of condensation technique (group 2. Specimens underwent microtomographic scanning. Collected data were statistically analyzed by nonparametric methods. Void mean percentages were found to be limited and similar between the two groups; the single point technique led to greater sealer thickness in partially oval canals.
Three wave coupling and explosive instability of magneto-elastic excitations in FeBO3 single crystal
International Nuclear Information System (INIS)
Yevstafyev, O.; Preobrazhensky, V.; Pernod, P.; Berzhansky, V.
2011-01-01
Parametric generation of coupled triads of magneto-elastic waves is studied experimentally in FeBO 3 single crystal under transversal electromagnetic pumping at the temperature range 77-293 K. The explosive supercritical dynamics of three wave coupling is observed when the pumping phase is modulated according to the nonlinear frequency shift of an excited magnetoelastic mode. The experimental results are in agreement with strongly nonlinear model of magneto-elastic excitations in antiferromagnets with 'easy plane' magnetic anisotropy. - Research highlights: → Parametric excitation of coupled magneto-elastic triads in FeBO 3 under EM pumping. → Quasi-singular pumping phase modulation to compensate nonlinear frequency shift. → Observation of explosive instability at the temperature range 77-293 K. → Supercritical triads excitation strongly nonlinear model of magneto-elastic dynamics.
Hollender, Peter J.; Rosenzweig, Stephen J.; Nightingale, Kathryn R.; Trahey, Gregg E.
2014-01-01
Acoustic radiation force impulse (ARFI) imaging and shear wave elasticity imaging (SWEI) use the dynamic response of tissue to impulsive mechanical stimulus to characterize local elasticity. A variant of conventional, multiple track location SWEI (MTL-SWEI), denoted single track location SWEI (STL-SWEI) offers the promise of creating speckle-free shear wave images. This work compares the three imaging modalities using a high push and track beam density combined acquisition sequence to image inclusions of different sizes and contrasts. STL-SWEI is shown to have significantly higher CNR than MTL-SWEI, allowing for operation at higher resolution. ARFI and STL-SWEI perform similarly in the larger inclusions, with STL-SWEI providing better visualization of small targets ≤2.5 mm in diameter. The processing of each modality introduces different trade-offs between smoothness and resolution of edges and structures; these are discussed in detail. PMID:25701531
Convergence of cranial visceral afferents within the solitary tract nucleus.
McDougall, Stuart J; Peters, James H; Andresen, Michael C
2009-10-14
Primary afferent axons within the solitary tract (ST) relay homeostatic information via glutamatergic synapses directly to second-order neurons within the nucleus of the solitary tract (NTS). These primary afferents arise from multiple organ systems and relay multiple sensory modalities. How this compact network organizes the flow of primary afferent information will shape central homeostatic control. To assess afferent convergence and divergence, we recorded ST-evoked synaptic responses in pairs of medial NTS neurons in horizontal brainstem slices. ST shocks activated EPSCs along monosynaptic or polysynaptic pathways. Gradations in shock intensity discriminated multiple inputs and stimulus recruitment profiles indicated that each EPSC was unitary. In 24 pairs, 75% were second-order neurons with 64% receiving one direct ST input with the remainder receiving additional convergent ST afferent inputs (22% two; 14% three monosynaptic ST-EPSCs). Some (34%) second-order neurons received polysynaptic EPSCs. Neurons receiving only higher-order inputs were uncommon (13%). Most ST-EPSCs were completely independent, but 4 EPSCs of a total of 81 had equal thresholds, highly correlated latencies, and synchronized synaptic failures consistent with divergence from a single source ST axon or from a common interneuron producing a pair of polysynaptic EPSCs. We conclude that ST afferent inputs are remarkably independent with little evidence of substantial shared information. Individual cells receive highly focused information from the viscera. Thus, afferent excitation of second-order NTS neurons is generally dominated by single visceral afferents and therefore focused on a single afferent modality and/or organ region.
Horizon wave function for single localized particles: GUP and quantum black-hole decay
International Nuclear Information System (INIS)
Casadio, Roberto; Scardigli, Fabio
2014-01-01
A localized particle in Quantum Mechanics is described by a wave packet in position space, regardless of its energy. However, from the point of view of General Relativity, if the particle's energy density exceeds a certain threshold, it should be a black hole. To combine these two pictures, we introduce a horizon wave function determined by the particle wave function in position space, which eventually yields the probability that the particle is a black hole. The existence of a minimum mass for black holes naturally follows, albeit not in the form of a sharp value around the Planck scale, but rather like a vanishing probability that a particle much lighter than the Planck mass may be a black hole. We also show that our construction entails an effective generalized uncertainty principle (GUP), simply obtained by adding the uncertainties coming from the two wave functions associated with a particle. Finally, the decay of microscopic (quantum) black holes is also described in agreement with what the GUP predicts. (orig.)
Photonic integrated single-sideband modulator / frequency shifter based on surface acoustic waves
DEFF Research Database (Denmark)
Barretto, Elaine Cristina Saraiva; Hvam, Jørn Märcher
2010-01-01
Optical frequency shifters are essential components of many systems. In this paper, a compact integrated optical frequency shifter is designed making use of the combination of surface acoustic waves and Mach-Zehnder interferometers. It has a very simple operation setup and can be fabricated in st...
Low Loss Single-Mode Porous-Core Kagome Photonic Crystal Fiber for THz Wave Guidance
DEFF Research Database (Denmark)
Hasanuzzaman, G. K. M.; Habib, Selim; Abdur Razzak, S. M.
2015-01-01
A novel porous-core kagome lattice photonic crystal fiber (PCF) is designed and analyzed in this paper for terahertz (THz) wave guidance. Using finite element method (FEM), properties of the proposed kagome lattice PCF are simulated in details including the effective material loss (EML...
Multi-exciton emission from solitary dopant states of carbon nanotubes.
Ma, Xuedan; Hartmann, Nicolai F; Velizhanin, Kirill A; Baldwin, Jon K S; Adamska, Lyudmyla; Tretiak, Sergei; Doorn, Stephen K; Htoon, Han
2017-11-02
By separating the photons from slow and fast decays of single and multi-exciton states in a time gated 2 nd order photon correlation experiment, we show that solitary oxygen dopant states of single-walled carbon nanotubes (SWCNTs) allow emission of photon pairs with efficiencies as high as 44% of single exciton emission. Our pump dependent time resolved photoluminescence (PL) studies further reveal diffusion-limited exciton-exciton annihilation as the key process that limits the emission of multi-excitons at high pump fluences. We further postulate that creation of additional permanent exciton quenching sites occurring under intense laser irradiation leads to permanent PL quenching. With this work, we bring out multi-excitonic processes of solitary dopant states as a new area to be explored for potential applications in lasing and entangled photon generation.
A large solitary liver metastasis of thymoma
International Nuclear Information System (INIS)
Kang, Si Won; Shinn, Kyung Sub
1997-01-01
Extrathoracic metastasis of a thymoma is rare ; we report a case of metastasis to the liver of a large solitary thymoma. Biopsy of the mass showed it to be predominantly lymphocytic and histologically the same as a primary thymoma operated on four years previously. On ultrasound and CT scan, the majority of the metastatic tumor was hemorrhagic, necrotic and/or cystic, with a peripheral, irregularly thick solid component and rather thin, smooth encapsulation
A large solitary liver metastasis of thymoma
Energy Technology Data Exchange (ETDEWEB)
Kang, Si Won; Shinn, Kyung Sub [Catholic Univ. College of Medicine, Seoul (Korea, Republic of)
1997-01-01
Extrathoracic metastasis of a thymoma is rare ; we report a case of metastasis to the liver of a large solitary thymoma. Biopsy of the mass showed it to be predominantly lymphocytic and histologically the same as a primary thymoma operated on four years previously. On ultrasound and CT scan, the majority of the metastatic tumor was hemorrhagic, necrotic and/or cystic, with a peripheral, irregularly thick solid component and rather thin, smooth encapsulation.
Pump-tunable continuous-wave singly resonant optical parametric oscillator from 2.5 to 4.4 microm.
Siltanen, Mikael; Vainio, Markku; Halonen, Lauri
2010-06-21
We report a continuous-wave singly resonant optical parametric oscillator pumped by a widely tunable titanium-doped sapphire ring laser. It produces up to 0.8 W of mid-infrared power. The wavelength can be tuned in a few seconds from 2.5 to 3.5 microm or from 3.4 to 4.4 microm and scanned up to 40 GHz without mode-hops by only changing the pump beam wavelength. Spectroscopic capability is demonstrated by measuring parts of the photoacoustic absorption spectrum of NH(3) near 3196 cm(-1).
Zeil, Peter; Thilmann, Nicky; Pasiskevicius, Valdas; Laurell, Fredrik
2014-12-01
A continuous-wave singly-resonant optical parametric oscillator (SRO) with an optimum extraction efficiency, that can be adjusted independent of the pump power, is demonstrated. The scheme employs a variable-reflectivity volume Bragg grating (VBG) as the output coupler of a ring cavity, omitting any additional intra-cavity elements. In this configuration, we obtained a 75%-efficient SRO with a combined signal (19 W @ 1.55 µm) and idler (11 W @ 3.4 µm) output power of 30 W.
Simultaneous single-shot readout of multi-qubit circuits using a traveling-wave parametric amplifier
O'Brien, Kevin
Observing and controlling the state of ever larger quantum systems is critical for advancing quantum computation. Utilizing a Josephson traveling wave parametric amplifier (JTWPA), we demonstrate simultaneous multiplexed single shot readout of 10 transmon qubits in a planar architecture. We employ digital image sideband rejection to eliminate noise at the image frequencies. We quantify crosstalk and infidelity due to simultaneous readout and control of multiple qubits. Based on current amplifier technology, this approach can scale to simultaneous readout of at least 20 qubits. This work was supported by the Army Research Office.
The superposition method in seeking the solitary wave solutions to ...
Indian Academy of Sciences (India)
Department of Engineering Mechanics, Hunan University, Changsha 410 082, China. E-mail: xieyuanxi88@163.com. MS received 24 September 2004; revised 18 September 2005; accepted 24 January 2006. Abstract. In this paper, starting from the careful analysis on the characteristics of the Burgers equation and the KdV ...
Solitary wave solutions of two-dimensional nonlinear Kadomtsev ...
Indian Academy of Sciences (India)
Aly R Seadawy
2017-09-13
Sep 13, 2017 ... [13] M M Lin and W S Duan, Chaos, Solitons and Fractals. 33, 1189 (2007). [14] S Singh and T Honzawa, Phys. Fluids B 5, 2093 (1993). [15] A R Seadawy, Eur. Phys. J. Plus, 130 (2015). [16] T S Gill, N S Saini and H Kaur, Chaos, Solitons and. Fractals 28, 1106 (2006). [17] A R Seadawy, Comput. Math.
Solitary wave solutions to nonlinear evolution equations in ...
Indian Academy of Sciences (India)
2Department of Engineering Sciences, Faculty of Technology and Engineering, East of Guilan,. University of Guilan, P.C. ... to investigate various tools of integration that extract various forms of analytical solutions to these ... The two subsequent sections will devote to integrate these equations sequentially. The integration ...
Solitary wave solutions of selective nonlinear diffusion-reaction ...
Indian Academy of Sciences (India)
ods are of general nature in the sense that they can be employed to any NLPDE, others are equation-specific. In this paper, using the homogeneous balance ..... investigated in the literature in a localized space-time domain using the so-called approximation methods [3], the exact solutions obtained here, of course by using.
Solitary wave solutions of two-dimensional nonlinear Kadomtsev ...
Indian Academy of Sciences (India)
Aly R Seadawy
2017-09-13
Sep 13, 2017 ... We considered the two-dimensional DASWs in colli- sionless, unmagnetized cold plasma consisting of dust fluid, ions and electrons. The dynamics of DASWs is governed by the normalized fluid equations of nonlin- ear continuity (1), nonlinear motion of system (2) and. (3) and linear Poisson equation (4) as.
Solitary Wave Effects North of Strait of Messina
2007-01-01
including suggestions for reducing the burden, to the Department of Defense, Executive Services and Communications Directorate (0704-0188). Respondents... Elman , H.C., Schultz, M.H., 1983. Variational iterative methods for nonsymmetric systems of linear equations. SIAM Journal of Numerical Analysis 20, 345
Solitary wave solutions to nonlinear evolution equations in ...
Indian Academy of Sciences (India)
This paper obtains solitons as well as other solutions to a few nonlinear evolution equations that appear in various areas of mathematical physics. The two analytical integrators that are applied to extract solutions are tan–cot method and functional variable approaches. The soliton solutions can be used in the further study of ...
Solitary Rossby waves in the lower tropical troposphere | Lenouo ...
African Journals Online (AJOL)
Weakly nonlinear approximation is used to study the theoretical comportment of large-scale disturbances around the inter-tropical mid-tropospheric jet. We show here that the Korteweg de Vries (KdV) theory is appropriated to describe the structure of the streamlines around the African easterly jet (AEJ) region.
Solitary wave solutions of selective nonlinear diffusion-reaction ...
Indian Academy of Sciences (India)
An auto-Bäcklund transformation derived in the homogeneous balance method is employed to obtain several new exact solutions of certain kinds of nonlinear diffusion-reaction (D-R) equations. These equations arise in a variety of problems in physical, chemical, biological, social and ecological sciences.
Solitary wave solutions of selective nonlinear diffusion-reaction ...
Indian Academy of Sciences (India)
An auto-Bäcklund transformation derived in the homogeneous balance method is employed to obtain several new exact solutions of certain kinds of nonlin- ear diffusion-reaction (D-R) equations. These equations arise in a variety of problems in physical, chemical, biological, social and ecological sciences. Keywords.
Stable complex solitary waves of Sasa Satsuma equation
Indian Academy of Sciences (India)
dispersion (TOD), self-steeping (SS) related to Kerr effect and the self frequency shifting via stimulated Raman scattering. It is the last term, which plays an important role in the propagation of distortionless optical pulses over a long distance. But the contribution from the last three terms becomes appreciable only for the very ...
Energy Technology Data Exchange (ETDEWEB)
Kang, To; Song, Sung Jin; Kim, Hark Joon [Sungkyunkwan University, Suwon (Korea, Republic of); Cho, Young Do; Lee, Dong Hoon [Korea Gas Safety Corporation, Seongnam (Korea, Republic of); Cho, Hyun Joon [Advanced Institute of Quality and Safety, Uiwang (Korea, Republic of)
2009-12-15
Excitation and propagation of guided waves are very complex problems in pipes due to their dispersive nature. Pipes are commonly used in the oil, chemical or nuclear industry and hence must be inspected regularly to ensure continued safe operation. The normal mode expansion(NME) method is given for the amplitude with which any propagating waveguide mode is generated in the pipes by applied surface tractions. Numerical results are calculated based on the NME method using different sources, i.e., non-axisymmetric partial loading and quasi-axisymmetric loading sources. The sum of amplitude coefficients for 0{approx}ninth order of the harmonic modes are calculated based on the NME method and the dispersion curves in pipes. The superimposed total field which is namely the angular profile, varies with propagating distance and circumferential angle. This angular profile of guided waves provides information for setting the transducer position to find defects in pipes.
Square wave stripping voltammetry of unlabeled single- and double-stranded DNAs
Czech Academy of Sciences Publication Activity Database
Bartošík, Martin; Paleček, Emil
2011-01-01
Roč. 23, č. 6 (2011), s. 1311-1319 ISSN 1040-0397 R&D Projects: GA MŠk(CZ) ME09038; GA MŠk(CZ) LC06035 Grant - others:GA ČR(CZ) GAP301/11/2055 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : square wave voltammetry * nucleic acids * mercury electrode Subject RIV: BO - Biophysics Impact factor: 2.872, year: 2011
Iqbal, Nadeem; Assad, Salman; Rahat Aleman Bhatti, Joshua; Hasan, Aisha; Shabbir, Muhammad Usman; Akhter, Saeed
2016-01-01
Objective To retrospectively evaluate the effectiveness of extracorporeal shock wave lithotripsy (ESWL) for urolithiasis and compare the results between children and adults. Materials and methods From January 2011 to January 2015 (four years), ESWL was performed in 104 children and 300 adults for urolithiasis. MODULITH? SLX-F2 lithotripter (Storz Medical AG, T?gerwilen, Switzerland) equipment was used for ESWL. The stone-free rates, the number of ESWL sessions required, complication rates and...
Czech Academy of Sciences Publication Activity Database
Šiler, Martin; Zemánek, Pavel
2011-01-01
Roč. 13, č. 4 (2011), 044016:1-9 ISSN 2040-8978 R&D Projects: GA MŠk(CZ) LC06007; GA MŠk OC08034; GA MŠk ED0017/01/01 Institutional research plan: CEZ:AV0Z20650511 Keywords : optical tweezers * optical lattice * optical force * evanescent wave Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.573, year: 2011
Solitary Large Intestinal Diverticulitis in Leatherback Turtles (Dermochelys coriacea).
Stacy, B A; Innis, C J; Daoust, P-Y; Wyneken, J; Miller, M; Harris, H; James, M C; Christiansen, E F; Foley, A
2015-07-01
Leatherback sea turtles are globally distributed and endangered throughout their range. There are limited data available on disease in this species. Initial observations of solitary large intestinal diverticulitis in multiple leatherbacks led to a multi-institutional review of cases. Of 31 subadult and adult turtles for which complete records were available, all had a single exudate-filled diverticulum, as large as 9.0 cm in diameter, arising from the large intestine immediately distal to the ileocecal junction. All lesions were chronic and characterized by ongoing inflammation, numerous intralesional bacteria, marked attenuation of the muscularis, ulceration, and secondary mucosal changes. In three cases, Morganella morganii was isolated from lesions. Diverticulitis was unrelated to the cause of death in all cases, although risk of perforation and other complications are possible. © The Author(s) 2014.
The imaging diagnosis of costal solitary eosinophilic granuloma
International Nuclear Information System (INIS)
Cui Fa; Feng Shiting
2007-01-01
Objective: To study the imaging features of costal eosinophilic granuloma so as to improve diagnosis accuracy of the disease. Methods: The clinical and imaging materials of 6 patients with costal solitary eosinophilic granuloma which were proved by surgery or histopathology were analyzed retrospectively. X-ray plain films were performed in all the cases, CT in 3 cases, 2 cases were received CT plain scan and I case received both CT plain scan and enhanced CT scan. Results: 4 cases of them located in the anterior ribs. All the lesions were round-like and 5 were single cavity and 1 was multiple cavities. 3 of them were expansile destruction and 3 were cystic destruction. Soft tissue mass around the lesion was identified. Conclusion: X-ray plain films integrating CT play an important role in diagnosis and differential diagnosis of the costal eosinophilic granuloma. (authors)
Crack Detection in Single-Crystalline Silicon Wafer Using Laser Generated Lamb Wave
Directory of Open Access Journals (Sweden)
Min-Kyoo Song
2013-01-01
Full Text Available In the semiconductor industry, with increasing requirements for high performance, high capacity, high reliability, and compact components, the crack has been one of the most critical issues in accordance with the growing requirement of the wafer-thinning in recent years. Previous researchers presented the crack detection on the silicon wafers with the air-coupled ultrasonic method successfully. However, the high impedance mismatching will be the problem in the industrial field. In this paper, in order to detect the crack, we propose a laser generated Lamb wave method which is not only noncontact, but also reliable for the measurement. The laser-ultrasonic generator and the laser-interferometer are used as a transmitter and a receiver, respectively. We firstly verified the identification of S0 and A0 lamb wave modes and then conducted the crack detection under the thermoelastic regime. The experimental results showed that S0 and A0 modes of lamb wave were clearly generated and detected, and in the case of the crack detection, the estimated crack size by 6 dB drop method was almost equal to the actual crack size. So, the proposed method is expected to make it possible to detect the crack in the silicon wafer in the industrial fields.
Engelbrecht, Jüri
2015-01-01
This book addresses the modelling of mechanical waves by asking the right questions about them and trying to find suitable answers. The questions follow the analytical sequence from elementary understandings to complicated cases, following a step-by-step path towards increased knowledge. The focus is on waves in elastic solids, although some examples also concern non-conservative cases for the sake of completeness. Special attention is paid to the understanding of the influence of microstructure, nonlinearity and internal variables in continua. With the help of many mathematical models for describing waves, physical phenomena concerning wave dispersion, nonlinear effects, emergence of solitary waves, scales and hierarchies of waves as well as the governing physical parameters are analysed. Also, the energy balance in waves and non-conservative models with energy influx are discussed. Finally, all answers are interwoven into the canvas of complexity.
Kelley, Luke Zoltan; Blecha, Laura; Hernquist, Lars; Sesana, Alberto; Taylor, Stephen R.
2018-03-01
We calculate the properties, occurrence rates and detection prospects of individually resolvable `single sources' in the low frequency gravitational wave (GW) spectrum. Our simulations use the population of galaxies and massive black hole binaries from the Illustris cosmological hydrodynamic simulations, coupled to comprehensive semi-analytic models of the binary merger process. Using mock pulsar timing arrays (PTA) with, for the first time, varying red-noise models, we calculate plausible detection prospects for GW single sources and the stochastic GW background (GWB). Contrary to previous results, we find that single sources are at least as detectable as the GW background. Using mock PTA, we find that these `foreground' sources (also `deterministic'/`continuous') are likely to be detected with ˜ 20 yr total observing baselines. Detection prospects, and indeed the overall properties of single sources, are only moderately sensitive to binary evolution parameters—namely eccentricity & environmental coupling, which can lead to differences of ˜ 5 yr in times to detection. Red noise has a stronger effect, roughly doubling the time to detection of the foreground between a white-noise only model (˜ 10 - 15 yr) and severe red noise (˜20 - 30 yr). The effect of red noise on the GWB is even stronger, suggesting that single source detections may be more robust. We find that typical signal-to-noise ratios for the foreground peak near f = 0.1 yr-1, and are much less sensitive to the continued addition of new pulsars to PTA.
Oh, Haekwan; Fu, Chen; Kim, Kunnyun; Lee, Keekeun
2014-11-17
A Love wave-based biosensor with a 440 MHz center frequency was developed for the simultaneous detection of two different analytes of Cartilage Oligomeric Matrix Protein (COMP) and rabbit immunoglobulin G (IgG) in a single sensor. The developed biosensor consists of one-port surface acoustic wave (SAW) reflective delay lines on a 41° YX LiNbO3 piezoelectric substrate, a poly(methyl methacrylate) (PMMA) waveguide layer, and two different sensitive films. The Love wave biosensor was wirelessly characterized using two antennas and a network analyzer. The binding of the analytes to the sensitive layers induced a large change in the time positions of the original reflection peaks mainly due to the mass loading effect. The assessed time shifts in the reflection peaks were matched well with the predicted values from coupling of mode (COM) modeling. The sensitivities evaluated from the sensitive films were ~15 deg/µg/mL for the rabbit IgG and ~1.8 deg/ng/mL for COMP.
Directory of Open Access Journals (Sweden)
Haekwan Oh
2014-11-01
Full Text Available A Love wave-based biosensor with a 440 MHz center frequency was developed for the simultaneous detection of two different analytes of Cartilage Oligomeric Matrix Protein (COMP and rabbit immunoglobulin G (IgG in a single sensor. The developed biosensor consists of one-port surface acoustic wave (SAW reflective delay lines on a 41° YX LiNbO3 piezoelectric substrate, a poly(methyl methacrylate (PMMA waveguide layer, and two different sensitive films. The Love wave biosensor was wirelessly characterized using two antennas and a network analyzer. The binding of the analytes to the sensitive layers induced a large change in the time positions of the original reflection peaks mainly due to the mass loading effect. The assessed time shifts in the reflection peaks were matched well with the predicted values from coupling of mode (COM modeling. The sensitivities evaluated from the sensitive films were ~15 deg/µg/mL for the rabbit IgG and ~1.8 deg/ng/mL for COMP.
Kevrekidis, P. G.; Carretero-González, R.; Frantzeskakis, D. J.
2017-04-01
We examine the spectral properties of single and multiple matter-wave dark solitons in Bose-Einstein condensates confined in parabolic traps, where the scattering length is periodically modulated. In addition to the large density limit picture previously established for homogeneous nonlinearities, we explore a perturbative analysis in the vicinity of the linear limit, which provides good agreement with the observed spectral modes. Between these two analytically tractable limits, we use numerical computations to fill in the relevant intermediate regime. We find that the scattering length modulation can cause a variety of features absent for homogeneous nonlinearities. Among them, we note the potential oscillatory instability even of the single dark soliton, the potential absence of instabilities in the immediate vicinity of the linear limit for two dark solitons, and the existence of an exponential instability associated with the in-phase motion of three dark solitons.
Strongly nonlinear waves in a chain of Teflon beads
Daraio, C.; Nesterenko, V. F.; Herbold, E. B.; Jin, S.
2005-01-01
One-dimensional “sonic vacuum” type phononic crystals were assembled from a chain of polytetrafluoroethylene (PTFE,Teflon) spheres with different diameters in a Teflon holder. It was demonstrated that this polymer-based sonic vacuum, with exceptionally low elastic modulus of particles, supports propagation of strongly nonlinear solitary waves with a very low speed. These solitary waves can be described using the classical nonlinear Hertz law despite the viscoelastic nature of the polymer and ...
Potential use of point shear wave elastography for the pancreas: A single center prospective study
Energy Technology Data Exchange (ETDEWEB)
Kawada, Natsuko, E-mail: kawada-na@mc.pref.osaka.jp [Department of Pathology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari, Osaka 537-8511 (Japan); Department of Gastroenterology, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa 920-0293 (Japan); Tanaka, Sachiko, E-mail: sachi686@cocoa.plala.or.jp [Osaka Center for Cancer and Cardiovascular Disease Prevention, 1-6-107, Morinomiya, Johtoh, Osaka 536-8588 (Japan); Uehara, Hiroyuki, E-mail: uehara-hi@mc.pref.osaka.jp [Department of Gastroenterology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari, Osaka 537-8511 (Japan); Ohkawa, Kazuyoshi, E-mail: okawa-ka@mc.pref.osaka.jp [Department of Gastroenterology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari, Osaka 537-8511 (Japan); Yamai, Takuo, E-mail: yamai-ta@mc.pref.osaka.jp [Department of Gastroenterology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari, Osaka 537-8511 (Japan); Takada, Ryoji, E-mail: takada-ry@mc.pref.osaka.jp [Department of Gastroenterology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari, Osaka 537-8511 (Japan); Shiroeda, Hisakazu, E-mail: shiroeda@kanazawa-med.ac.jp [Department of Gastroenterology, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa 920-0293 (Japan); Arisawa, Tomiyasu, E-mail: tarisawa@kanazawa-med.ac.jp [Department of Gastroenterology, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa 920-0293 (Japan); Tomita, Yasuhiko, E-mail: tomota-ya@mc.pref.osaka.jp [Department of Pathology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari, Osaka 537-8511 (Japan)
2014-04-15
Aim: Clinical use of point shear wave elastography for the liver has been established, however, few studies demonstrated its usefulness for the pancreas. A prospective study was conducted to clarify its feasibility for the pancreas and its usefulness for the identification of high risk group for pancreatic cancer. Patients and methods: Consecutive eighty-five patients underwent point shear wave elastography for the pancreas. The success rate of shear wave velocity (SWV) measurement, that is the number of successful measurements over total 10 measurements, was recorded. The SWV of the pancreas measured at non-tumorous area was compared between patients with and without pancreatic cancer. Factors associated with high SWV were determined by logistic regression model. Results: Sixty patients were included, of these 18 had pancreatic cancer. The success rate of 100% was achieved at the head, the body and the tail of the pancreas in 80%, 83%, and 68% of the patients, respectively. The success rate of ≥80% was achieved in 100%, 100%, and 96% of the patients, respectively. Although mean SWV of the pancreas harboring pancreatic cancer tended to be higher compared with that of the pancreas without cancer (1.51 ± 0.45 m/s vs 1.43 ± 0.28 m/s), they did not reach statistical significance. Multivariate analysis showed that increased amount of alcohol intake was associated with high SWV. Conclusion: The SWV of the pancreas was measured with excellent success rate. However, tendency of higher SWV obtained from the pancreas harboring pancreatic cancer needed to be further investigated.
Malignant solitary fibrous tumor metastatic to the orbit.
Glazer-Hockstein, Carolyn; Syed, Nasreen A; Warhol, Michael; Gausas, Roberta E
2004-11-01
A 61-year-old man with a history of malignant solitary fibrous tumor of the chest had development of unusual sites of metastasis involving the sphenoid wing of the orbit and soft tissues of the cheek. He was found to have a solitary fibrous tumor, an uncommon type of spindle cell neoplasm that most often arises in the pleura, which was metastatic to the orbit. This is the first reported case of malignant solitary fibrous tumor metastatic to the orbit. The clinical and histopathologic findings of metastatic malignant solitary fibrous tumor are described.
The cruel and unusual phenomenology of solitary confinement.
Gallagher, Shaun
2014-01-01
What happens when subjects are deprived of intersubjective contact? This paper looks closely at the phenomenology and psychology of one example of that deprivation: solitary confinement. It also puts the phenomenology and psychology of solitary confinement to use in the legal context. Not only is there no consensus on whether solitary confinement is a "cruel and unusual punishment," there is no consensus on the definition of the term "cruel" in the use of that legal phrase. I argue that we can find a moral consensus on the meaning of "cruelty" by looking specifically at the phenomenology and psychology of solitary confinement.
Recovery of Stokes waves from velocity measurements on an axis of symmetry
International Nuclear Information System (INIS)
Matioc, Bogdan-Vasile
2015-01-01
We provide a new method to recover the profile of Stokes waves, and more generally of waves with smooth vorticity, from measurements of the horizontal velocity component on a vertical axis of symmetry of the wave surface. Although we consider periodic waves only, the extension to solitary waves is straightforward. (paper)
Daliri, Seyedeh Somayeh; Forogh, Bijan; Emami Razavi, Seyedeh Zahra; Ahadi, Tannaz; Madjlesi, Faezeh; Ansari, Noureddin Nakhostin
2015-01-01
Spasticity is a common, serious symptom after stroke. Extracorporeal shock wave therapy (ESWT) has been suggested for the treatment of muscle spasticity. To investigate the effects of ESWT on post stroke wrist flexor spasticity. Fifteen patients with poststroke wrist flexor spasticity (12 male and 3 female with a mean age of 54 years) were enrolled. Patients received 1 sham ESWT followed by 1 active ESWT 1 week later. The outcome measures were the Modified Modified Ashworth Scale (MMAS), the Hmax/Mmax ratio, and the Brunnstrom motor recovery stage. The sham ESWT had not effects on the outcome measures. After active ESW, the MMAS scores of spasticity and the Hmax/Mmax ratio improved. The improvements were maintained 5 weeks after active ESWT. No significant improvements were observed for the motor recovery after sham or active ESWT. In adult patients after stroke, a single session of active ESWT resulted in significant improvement in the wrist flexor spasticity and alpha motor neuron excitability.
Solitary structures in an inhomogeneous plasma with pseudo-potential approach
Shan, Shaukat Ali; Saleem, Hamid
2017-11-01
The set of nonlinear partial differential equations for the coupled ion acoustic and drift waves is reduced to the KdV equation, which is finally transformed into the form of energy integral equation of a pseudo particle in small amplitude limit. It is pointed out that this approach is convenient for choosing appropriate plasma parameters and numerically obtaining drift solitary wave profiles as compared to the solution of the KdV equation, particularly, in non-uniform plasmas. Electrons are assumed to follow the Kappa distribution function. It is found that the solitons amplitude decreases corresponding to steeper density and temperature gradients because of the restriction on the validity of local approximation. Deviation of electrons from thermal equilibrium distribution is supportive for the formation of electrostatic solitary structures by the coupled nonlinear ion acoustic and drift waves. The estimates of the width of the solitons formed by these coupled nonlinear electrostatic waves in the F-region ionosphere are found to be a few meters in agreement with the satellite observations.
Efficient Wave Energy Amplification with Wave Reflectors
DEFF Research Database (Denmark)
Kramer, Morten Mejlhede; Frigaard, Peter Bak
2002-01-01
Wave Energy Converters (WEC's) extract wave energy from a limited area, often a single point or line even though the wave energy is generally spread out along the wave crest. By the use of wave reflectors (reflecting walls) the wave energy is effectively focused and increased to approximately 130...... for different geometries of the wave reflectors and optimal geometrical design parameters are specified. On this basis inventors of WEC's can evaluate whether a specific WEC possible could benefit from wave reflectors....
A numerical model of acoustic wave caused by a single positive corona source
Zhang, Bo; Li, Zhen; He, Jinliang
2017-10-01
Audible noise accompanies corona discharge, which is one of the most important electromagnetic environment issues of high voltage transmission lines. Most of the studies on the audible noise generated by corona discharge focused on statistical analysis of the experimental results and a series of empirical formulas were derived to predict the audible noise. However, few of them interpreted the generating mechanism of the audible noise. Sound wave in the air is actually the fluctuation of the air, which lead to the hypothesis that the sound wave is generated by the interaction of the charged particles and the air molecules in the discharge progress. To validate this hypothesis, experiments were carried out in this paper to study the relationship between the audible noise and the corona current, including the correlation both in time domain and in frequency domain. Based on the experimental results, the fluid equations of the particles in the air were introduced to study the interactions among the electrons, ions, and neutral molecules in the discharge, and a numerical model for the amplitude of corona acoustic emission was developed and validated.
2015-09-30
Interaction of Surface Gravity Waves with Nonlinear Internal Gravity Waves Lian Shen St. Anthony Falls Laboratory and Department of Mechanical...on studying surface gravity wave evolution and spectrum in the presence of surface currents caused by strongly nonlinear internal solitary waves...interaction of surface and internal gravity waves in the South China Sea. We will seek answers to the following questions: 1) How does the wind-wave
International Nuclear Information System (INIS)
Samsing, Johan; MacLeod, Morgan; Ramirez-Ruiz, Enrico
2014-01-01
The inspiral and merger of eccentric binaries leads to gravitational waveforms distinct from those generated by circularly merging binaries. Dynamical environments can assemble binaries with high eccentricity and peak frequencies within the LIGO band. In this paper, we study binary-single stellar scatterings occurring in dense stellar systems as a source of eccentrically inspiraling binaries. Many interactions between compact binaries and single objects are characterized by chaotic resonances in which the binary-single system undergoes many exchanges before reaching a final state. During these chaotic resonances, a pair of objects has a non-negligible probability of experiencing a very close passage. Significant orbital energy and angular momentum are carried away from the system by gravitational wave (GW) radiation in these close passages, and in some cases this implies an inspiral time shorter than the orbital period of the bound third body. We derive the cross section for such dynamical inspiral outcomes through analytical arguments and through numerical scattering experiments including GW losses. We show that the cross section for dynamical inspirals grows with increasing target binary semi-major axis a and that for equal-mass binaries it scales as a 2/7 . Thus, we expect wide target binaries to predominantly contribute to the production of these relativistic outcomes. We estimate that eccentric inspirals account for approximately 1% of dynamically assembled non-eccentric merging binaries. While these events are rare, we show that binary-single scatterings are a more effective formation channel than single-single captures for the production of eccentrically inspiraling binaries, even given modest binary fractions.
Hossen, M. R.; Nahar, L.; Mamun, A. A.
2014-12-01
The properties of time-dependent cylindrical and spherical, modified ion-acoustic (mIA) solitary structures in relativistic degenerate multi-ion plasmas (containing degenerate electron fluids, inertial positively-, as well as negatively-, charged light ions, and positively-charged static heavy ions) have been investigated theoretically. This investigation is valid for both non-relativistic and ultra-relativistic limits. The well-known reductive perturbation method has been used to derive the Korteweg-de Vries (K-dV) and the mK-dV equations for studying the basic features of solitary waves. The fundamental characteristics of mIA solitary waves are found to be significantly modified by the effects of the degenerate pressures of the electron and the ion fluids, their number densities, and the various charge states of heavy ions. The relevance of our results in astrophysical compact objects like white dwarfs and neutron stars, which are of scientific interest, is briefly discussed.
Bloch surface waves confined in one dimension with a single polymeric nanofibre
Wang, Ruxue; Xia, Hongyan; Zhang, Douguo; Chen, Junxue; Zhu, Liangfu; Wang, Yong; Yang, Erchan; Zang, Tianyang; Wen, Xiaolei; Zou, Gang; Wang, Pei; Ming, Hai; Badugu, Ramachandram; Lakowicz, Joseph R.
2017-02-01
Polymeric fibres with small radii (such as ≤125 nm) are delicate to handle and should be laid down on a solid substrate to obtain practical devices. However, placing these nanofibres on commonly used glass substrates prevents them from guiding light. In this study, we numerically and experimentally demonstrate that when the nanofibre is placed on a suitable dielectric multilayer, it supports a guided mode, a Bloch surface wave (BSW) confined in one dimension. The physical origin of this new mode is discussed in comparison with the typical two-dimensional BSW mode. Polymeric nanofibres are easily fabricated to contain fluorophores, which make the dielectric nanofibre and multilayer configuration suitable for developing a large range of new nanometric scale devices, such as processor-memory interconnections, devices with sensitivity to target analytes, incident polarization and multi-colour BSW modes.
Millius, Arthur; Watanabe, Naoki; Weiner, Orion D.
2012-01-01
The SCAR/WAVE complex drives lamellipodium formation by enhancing actin nucleation by the Arp2/3 complex. Phosphoinositides and Rac activate the SCAR/WAVE complex, but how SCAR/WAVE and Arp2/3 complexes converge at sites of nucleation is unknown. We analyzed the single-molecule dynamics of WAVE2 and p40 (subunits of the SCAR/WAVE and Arp2/3 complexes, respectively) in XTC cells. We observed lateral diffusion of both proteins and captured the transition of p40 from diffusion to network incorporation. These results suggest that a diffusive 2D search facilitates binding of the Arp2/3 complex to actin filaments necessary for nucleation. After nucleation, the Arp2/3 complex integrates into the actin network and undergoes retrograde flow, which results in its broad distribution throughout the lamellipodium. By contrast, the SCAR/WAVE complex is more restricted to the cell periphery. However, with single-molecule imaging, we also observed WAVE2 molecules undergoing retrograde motion. WAVE2 and p40 have nearly identical speeds, lifetimes and sites of network incorporation. Inhibition of actin retrograde flow does not prevent WAVE2 association and disassociation with the membrane but does inhibit WAVE2 removal from the actin cortex. Our results suggest that membrane binding and diffusion expedites the recruitment of nucleation factors to a nucleation site independent of actin assembly, but after network incorporation, ongoing actin polymerization facilitates recycling of SCAR/WAVE and Arp2/3 complexes. PMID:22349699
Theoretical comparison of optical traps created by standing wave and single beam
Czech Academy of Sciences Publication Activity Database
Zemánek, Pavel; Jonáš, Alexandr; Jákl, Petr; Ježek, Jan; Šerý, Mojmír; Liška, M.
2003-01-01
Roč. 220, 4-6 (2003), s. 401 - 412 ISSN 0030-4018 R&D Projects: GA ČR GA101/00/0974 Institutional research plan: CEZ:AV0Z2065902 Keywords : single beam trap * optical trapping * optical tweezers Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.482, year: 2003
Fiber Laser Pumped Continuous-wave Singly-resonant Optical Parametric Oscillator
Klein, M.E.; Gross, P.; Walde, T.; Boller, Klaus J.; Auerbach, M.; Wessels, P.; Fallnich, C.; Fejer, Martin M.
2002-01-01
We report on the first fiber-pumped CW LiNbO/sub 3/ optical parametric oscillator (OPO). The OPO is singly resonant (SRO) and generates idler wavelengths in the range of 3.0 /spl mu/m to 3.7 /spl mu/m with a maximum output power of 1.9 watt.
Solitary lucent epiphyseal lesions in children
Energy Technology Data Exchange (ETDEWEB)
Gardner, D.J.; Azouz, E.M.
1988-10-01
We evaluated retrospectively the varying radiographic appearances of 15 solitary lucent epiphyseal lesions occurring in children. Imaging modalities used included plain films, conventional tomography, nuclear scintigraphy, and computed tomography. 40% of the lesions (6) were due to osteomyelitis. The remaining lesions included tuberculosis (1), foreign body granuloma (1), chondroblastoma (2), chondromyoxid fibroma (1), enchondroma (1), osteoid osteoma (2), and eosinophilic granuloma (1). Although the radiographic appearances of such lesions may be particularly characteristic, pathologic correlation is frequently necessary. The high incidence of osteomyelitis in our cases emphasizes its importance as a cause for a lucent epiphyseal lesion.
Solitary osteoma of body of the mandible
Directory of Open Access Journals (Sweden)
Saba Khan
2013-01-01
Full Text Available Osteomas are relatively rare benign osteogenic neoplasm′s characterized by the proliferation of compact or cancellous bone. Osteomas can develop as peripheral (periosteal masses attached to the cortical plates or as central lesions arising from endosteal bone surfaces. Although multiple osteomas of the jaws are a hallmark of Gardner′s syndrome (familial adenomatous polyposis, non-syndromic cases are typically solitary. The purpose of this paper is to present a large peripheral osteoma originating from the buccal surface of the mandible and causing asymmetry in a 35-year-old woman.
Perciaccante, Antonio; Coralli, Alessia
2015-01-01
A case of an anomaly in the maxillary dental arch on "Delphic Sibyl," a fresco by Michelangelo is reported. An accurate analysis of this fresco shows a single incisor tooth is present precisely in the midline. We hypothesize that it may be a case of solitary median maxillary central incisor (SMMCI) and discuss the differential diagnosis with another similar anomaly--the mesiodens.
Analytical travelling wave solutions and parameter analysis for the ...
Indian Academy of Sciences (India)
By using dynamical system method, this paper considers the (2+1)-dimensional Davey–Stewartson-type equations. The analytical parametric representations of solitary wave solutions, periodic wave solutions as well as unbounded wave solutions are obtained under different parameter conditions. A few diagrams ...
Analytical travelling wave solutions and parameter analysis for the
Indian Academy of Sciences (India)
By using dynamical system method, this paper considers the (2+1)-dimensional Davey–Stewartson-type equations. The analytical parametric representations of solitary wave solutions, periodic wave solutions as well as unbounded wave solutions are obtained under different parameter conditions. A few diagrams ...
Occurrence of submarine canyons, sediment waves and mass ...
Indian Academy of Sciences (India)
For example, frontally confined slide complexes could have been influenced by high sedimentation rates and high pore pressures. A series of very large subaqueous sediment waves, which record wavelengths of 1.4–2 km and wave heights of 30–50 m, were likely produced by interactions between internal solitary waves ...
3+1 dimensional envelop waves and its stability in magnetized dusty plasma
International Nuclear Information System (INIS)
Duan Wenshan
2006-01-01
It is well known that there are envelope solitary waves in unmagnetized dusty plasmas which are described by a nonlinear Schrodinger equation (NLSE). A three dimension nonlinear Schrodinger equation for small but finite amplitude dust acoustic waves is first obtained for magnetized dusty plasma in this paper. It suggest that in magnetized dusty plasmas the envelope solitary waves exist. The modulational instability for three dimensional NLSE is studied as well. The regions of stability and instability are well determined in this paper
Giant Solitary Hepatocellular Carcinoma. A Case Report. | Asuquo ...
African Journals Online (AJOL)
Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver, among indigenous inhabitants of Africa and it may present as solitary or multiple lesions often running a rapidly fatal course. Presented is a case of a 25 year female in apparent general good health with a giant solitary hepatocellular ...
Intramuscular cysticercosis – The solitary reaper | Singh | Annals of ...
African Journals Online (AJOL)
Occurrence of solitary intramuscular cysticercosis without involvement of the central nervous system is rare. We report a case of solitary cysticercosis of the brachioradialis muscle in a 35-year-old woman who presented with discomfort and pain in the right elbow and arm after trivial trauma. There were no systemic or ...
Solitary Plasmacytoma: A Review Of Clinical, Ocular, Neurological ...
African Journals Online (AJOL)
Solitary plasmacytomas are defined as proliferation of monoclonal plasma cells without evidence of significant bone-marrow plasma-cell infiltration. They are classified according to location into solitary plasmacytoma of bone if they occur in bone, and extramedullary plasmacytoma if they arise in soft tissues. They are more ...
Santini, Ario; Naaman, Reem Khalil; Aldossary, Mohammed Saeed
2017-04-01
To quantify light energy transmission through two bulk-fill resin-based composites and to measure the top to bottom surface Vickers hardness ratio (VHratio) of samples of various incremental thicknesses, using either a single-wave or dual-wave light curing unit (LCU). Tetric EvoCeram Bulk Fill (TECBF) and SonicFill (SF) were studied. Using MARC-RC, the irradiance delivered to the top surface of the samples 2, 3, 4 and 5 mm thick (n= 5 for each thickness) was adjusted to 800 mW/cm2 for 20 seconds (16 J/cm2) using either a single-wave, Bluephase or a dual-wave, Bluephase G2 LCUs. Light energy transmission through to the bottom surface of the specimens was measured at real time using MARC-RC. The Vickers hardness (VH) was determined using Vickers micro hardness tester and the VHratio was calculated. Data were analyzed using a general linear model in Minitab 16; α= 0.05. TECBF was more translucent than SF (Pcured with the dual-wave Bluephase G2). SF showed significantly higher VH ratio than TECBF at all different thickness levels (P 0.05). TECBF showed significantly greater VH ratio when cured with the single-wave Bluephase than when using the dual-wave Bluephase G2 (Plight energy through to the bottom surface and the VHratio are material dependent. Although TECBF is more translucent than SF, it showed lower VHratio compared to SF when cured with dual-wave Bluephase G2.
Spin wave eigenmodes in single and coupled sub-150 nm rectangular permalloy dots
Energy Technology Data Exchange (ETDEWEB)
Carlotti, G., E-mail: giovanni.carlotti@fisica.unipg.it; Madami, M. [Dipartimento di Fisica e Geologia, Università di Perugia, Perugia (Italy); Tacchi, S. [Istituto Officina dei Materiali del CNR (CNR-IOM), Dipartimento di Fisica e Geologia, Perugia (Italy); Gubbiotti, G.; Dey, H.; Csaba, G.; Porod, W. [Center for Nano Science and Technology, Department of Electrical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States)
2015-05-07
We present the results of a Brillouin light scattering investigation of thermally excited spin wave eigenmodes in square arrays of either isolated rectangular dots of permalloy or twins of dipolarly coupled elements, placed side-by-side or head-to-tail. The nanodots, fabricated by e-beam lithography and lift-off, are 20 nm thick and have the major size D in the range between 90 nm and 150 nm. The experimental spectra show the presence of two main peaks, corresponding to modes localized either at the edges or in the center of the dots. Their frequency dependence on the dot size and on the interaction with adjacent elements has been measured and successfully interpreted on the basis of dynamical micromagnetic simulations. The latter enabled us also to describe the spatial profile of the eigenmodes, putting in evidence the effects induced by the dipolar interaction between coupled dots. In particular, in twinned dots the demagnetizing field is appreciably modified in proximity of the “internal edges” if compared to the “external” ones, leading to a splitting of the edge mode. These results can be relevant for the exploitation of sub-150 nm magnetic dots in new applications, such as magnonic metamaterials, bit-patterned storage media, and nano-magnetic logic devices.
A temperature dependent tunneling study of the spin density wave gap in EuFe2As2 single crystals.
Dutta, Anirban; Anupam; Hossain, Z; Gupta, Anjan K
2013-09-18
We report temperature dependent scanning tunneling microscopy and spectroscopy measurements on single crystals of EuFe2As2 in the 15-292 K temperature range. The in situ cleaved crystals show atomic terraces with homogeneous tunnel spectra that correlate well with the spin density wave (SDW) transition at a temperature, TSDW ≈ 186 K. Above TSDW the local tunnel spectra show a small depression in the density of states (DOS) near the Fermi energy (EF). The gap becomes more pronounced upon entering the SDW state with a gap value ∼90 meV at 15 K. However, the zero bias conductance remains finite down to 15 K indicating a finite DOS at the EF in the SDW phase. Furthermore, no noticeable change is observed in the DOS at the antiferromagnetic ordering transition of Eu(2+) moments at 19 K.
Directory of Open Access Journals (Sweden)
E. Momoniat
2014-01-01
Full Text Available Two nonstandard finite difference schemes are derived to solve the regularized long wave equation. The criteria for choosing the “best” nonstandard approximation to the nonlinear term in the regularized long wave equation come from considering the modified equation. The two “best” nonstandard numerical schemes are shown to preserve conserved quantities when compared to an implicit scheme in which the nonlinear term is approximated in the usual way. Comparisons to the single solitary wave solution show significantly better results, measured in the L2 and L∞ norms, when compared to results obtained using a Petrov-Galerkin finite element method and a splitted quadratic B-spline collocation method. The growth in the error when simulating the single solitary wave solution using the two “best” nonstandard numerical schemes is shown to be linear implying the nonstandard finite difference schemes are conservative. The formation of an undular bore for both steep and shallow initial profiles is captured without the formation of numerical instabilities.
Solitary neurofibroma of eyelid masquerading as chalazion
Directory of Open Access Journals (Sweden)
Chen N
2017-05-01
Full Text Available Nancy Chen,1 Yung-Hsiang Hsu,2 Yuan-Chieh Lee1,3 1Department of Ophthalmology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan; 2Department of Pathology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan; 3Department of Ophthalmology and Visual Science, Tzu Chi University, Hualien, Taiwan Abstract: Neurofibroma, a benign peripheral nerve sheath tumor, usually appears together with café-au-lait spots, iris nodules, and other tumors within the scope of neurofibromatosis von Recklinghausen type 1 tumors. A solitary neurofibroma of the eyelid is relatively rare. In this case report, we present a 39-year-old woman who had a lesion on the eyelid crease, previously treated as a chalazion. Due to persistent wound crusting, the lesion was excised above the tarsus. Pathological examination revealed a solitary neurofibroma. The patient did not have other clinical symptoms of neurofibromatosis, and there was no recurrence of the nodule during the 1-year follow-up. Keywords: neurofibroma, eyelid tumor, chalazion
Radiation therapy for the solitary plasmacytoma
Directory of Open Access Journals (Sweden)
Esengül Koçak
2010-06-01
Full Text Available Plasma-cell neoplasms are classically categorized into four groups as: multiple myeloma (MM, plasma-cell leukemias, solitary plasmacytomas (SP of the bone (SPB, and extramedullary plasmacytomas (EMP. These tumors may be described as localized or diffuse in presentation. Localized plasma-cell neoplasms are rare, and include SP of the skeletal system, accounting for 2-5% of all plasma-cell neoplasms, and EMP of soft tissue, accounting for approximately 3% of all such neoplasms. SP is defined as a solitary mass of neoplastic plasma cells either in the bone marrow or in various soft tissue sites. There appears to be a continuum in which SP often progresses to MM. The main treatment modality for SP is radiation therapy (RT. However, there are no conclusive data in the literature on the optimal RT dose for SP. This review describes the interrelationship of plasma-cell neoplasms, and attempts to determine the minimal RT dose required to obtain local control.
The solitary sellar plasmacytoma: a diagnostic challenge
Directory of Open Access Journals (Sweden)
Anne Soejbjerg
2016-06-01
Full Text Available Solitary sellar plasmacytomas are exceedingly rare and difficult to distinguish from other pituitary tumors. We report a case of a 62-year-old woman presenting with blurred vision of the right eye and tenderness of the right temporal region, which was interpreted as temporal arteritis. MRI revealed a pituitary mass lesion (20mm×14mm×17mm without compression of the optic chiasm and her pituitary function was normal. Pituitary surgery was undertaken due to growth of the lesion, and histopathological examination showed a highly cellular neoplasm composed of mature monoclonal plasma cells. Subsequent examinations revealed no evidence of extrasellar myeloma. The patient received pituitary irradiation and has remained well and free of symptoms apart from iatrogenic central diabetes insipidus. Until now, only eight cases of solitary sellar plasmacytoma have been reported. Most frequent symptoms stem from compression of the cranial nerves in the cavernous sinus (III, IV, V, whereas the anterior pituitary function is mostly intact.
EL-Shamy, E. F.; Gohman, F. S.; Alqahtani, M. M.; AlFaify, S.
2018-01-01
An investigation is presented to examine nonlinear electrostatic waves in a quantum semiconductor plasma. A quantum semiconductor plasma model consisting of electrons and holes is going to be used, which includes exchange-correlation potentials, the quantum recoil effect, and degenerate pressures of electrons and holes. Actually, a nonlinear solitary pulse can be used to represent the intrinsic coherent electrostatic wave in a quantum semiconductor plasma. The propagation and the collision of nonlinear solitary pulses are examined by the extended Poincaré-Lighthill-Kuo method. Typical values for the GaAs semiconductors are employed to investigate the basic characteristics of solitary pulses. The numerical studies show that the energies and then the trajectories of nonlinear solitary pulses after the collision are significantly changed due to the effects of the exchange and correlation potentials and the variety in the studied system's geometry. The results obtained here may be useful for gaining a better understanding of the basic features of the nonlinear solitary pulses in quantum semiconductor plasmas.
Solitary and blow-up electrostatic excitations in rotating magnetized electron-positron-ion plasmas
Moslem, W. M.; Sabry, R.; Abdelsalam, U. M.; Kourakis, I.; Shukla, P. K.
2009-03-01
The nonlinear dynamics of a rotating magnetoplasma consisting of electrons, positrons and stationary positive ions is considered. The basic set of hydrodynamic and Poisson equations are reduced to a Zakharov-Kuznetsov (ZK) equation for the electric potential. The ZK equation is solved by applying an improved modified extended tanh-function method (2008 Phys. Lett. A 372 5691) and its characteristics are investigated. A set of new solutions are derived, including localized solitary waves, periodic nonlinear waveforms and divergent (explosive) pulses. The characteristics of these nonlinear excitations are investigated in detail.
Solitary and blow-up electrostatic excitations in rotating magnetized electron-positron-ion plasmas
Energy Technology Data Exchange (ETDEWEB)
Moslem, W M; Sabry, R; Abdelsalam, U M; Shukla, P K [Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Kourakis, I [Centre for Plasma Physics, Department of Physics and Astronomy, Queen' s University Belfast, BT7 1 NN Northern Ireland (United Kingdom)], E-mail: wmmoslem@hotmail.com, E-mail: wmm@tp4.rub.de, E-mail: sabryphys@yahoo.com, E-mail: refaatsabry@mans.edu.eg, E-mail: maths_us@hotmail.com, E-mail: i.kourakis@qub.ac.uk, E-mail: ps@tp4.rub.de
2009-03-15
The nonlinear dynamics of a rotating magnetoplasma consisting of electrons, positrons and stationary positive ions is considered. The basic set of hydrodynamic and Poisson equations are reduced to a Zakharov-Kuznetsov (ZK) equation for the electric potential. The ZK equation is solved by applying an improved modified extended tanh-function method (2008 Phys. Lett. A 372 5691) and its characteristics are investigated. A set of new solutions are derived, including localized solitary waves, periodic nonlinear waveforms and divergent (explosive) pulses. The characteristics of these nonlinear excitations are investigated in detail.
Directory of Open Access Journals (Sweden)
Konstantinos N. Stamatiou
2010-12-01
Full Text Available PURPOSE: To compare the efficacy and safety of the electromagnetic lithotripter in the treatment of pediatric lithiasis to that of the earlier electrohydraulic model. MATERIALS AND METHODS: Two groups of children with lithiasis aged between 10 and 180 months who underwent extracorporeal shock wave lithotripsy (ESWL. In the first group (26 children, ESWL was performed by using the electrohydraulic MPL 9000X Dornier lithotripter between 1994 and 2003 while in the second group (19 children the electromagnetic EMSE 220 F-XP Dornier lithotripter was used from April 2003 to May 2006. RESULTS: In the first group, 21/26 children (80.7% were stone free at first ESWL session. Colic pain resolved by administration of an oral analgesic in 6 (23%, brief hematuria (< 24 h resolved with increased fluid intake in 5 (19.2%, while slightly elevated body temperature (< 38°C occurred in 4 (15.3%. Four children (15.3% failed to respond to treatment and were treated with ureteroscopy. In the second group 18/19 children were completely stone free at first ESWL session (94.7%. Complications were infrequent and of minor importance: colic pain treated with oral analgesic occurred in 1 (5.26%, brief hematuria (< 24 h, resolved with increased fluid intake in 4 (21% and slightly elevated body temperature (< 38°C monitored for 48 hours occurred in 6 (31.5%. Statistical analysis showed that electromagnetic lithotripter is more efficacious and safer than the earlier electrohydraulic model. CONCLUSIONS: Technological development not only has increased efficacy and safety of lithotripter devices in treating pediatric lithiasis, but it also provided less painful lithotripsy by eliminating the need for general anesthesia.
Continuous-wave singly resonant optical parametric oscillator placed inside a ring laser.
Abitan, Haim; Buchhave, Preben
2003-11-20
A cw singly resonant optical parametric oscillator (SRO) was built and placed inside the cavity of a ring laser. The system consists of a diode-end-pumped Nd:YVO4 ring laser with intracavity periodically poled lithium niobate as the nonlinear gain medium of the SRO. When the laser was operated in a unidirectional mode, we obtained more than 520 mW of signal power in one beam. When the laser was operated in a bidirectional mode, we obtained 600 mW of signal power (300 mW in two separate beams). The power and the spectral features of the laser in the unidirectional and bidirectional modes were measured while the laser was coupled with the SRO. The results show that it is preferable to couple a SRO with a unidirectional ring laser.
Continuous-wave singly resonant optical parametric oscillator placed inside a ring laser
DEFF Research Database (Denmark)
Abitan, Haim; Buchhave, Preben
2003-01-01
in a unidirectional mode, we obtained more than 520 mW of signal power in one beam. When the laser was operated in a bidirectional mode, we obtained 600 mW of signal power (300 mW in two separate beams). The power and the spectral features of the laser in the unidirectional and bidirectional modes were measured while......A cw singly resonant optical parametric oscillator (SRO) was built and placed inside the cavity of a ring laser. The system consists of a diode-end-pumped Nd:YVO4 ring laser with intracavity periodically poled lithium niobate as the nonlinear gain medium of the SRO. When the laser was operated...... the laser was coupled with the SRO. The results show that it is preferable to couple a SRO with a unidirectional ring laser....
Bonifazi, Giuseppe; Palmieri, Roberta; Serranti, Silvia
2015-03-01
Postconsumer plastics from packing and packaging represent about the 60% of the total plastic wastes (i.e. 23 million of tons) produced in Europe. The EU Directive (2014/12/EC) fixes as target that the 60%, by weight, of packaging waste has to be recovered, or thermally valorized. When recovered, the same directive established that packaging waste has to be recycled in a percentage ranging between 55% (minimum) and 60% (maximum). The non-respect of these rules can produce that large quantities of end-of-life plastic products, specifically those utilized for packaging, are disposed-off, with a strong environmental impact. The application of recycling strategies, finalized to polymer recovery, can represent an opportunity to reduce: i) not renewable raw materials (i.e. oil) utilization, ii) carbon dioxide emissions and iii) amount of plastic waste disposed-off. Aim of this work was to perform a full characterization of different end-of-life polymers based products, constituted not only by single polymers but also of mixtures, in order to realize their identification for quality control and/or certification assessment. The study was specifically addressed to characterize the different recovered products as resulting from a recycling plant where classical processing flow-sheets, based on milling, classification and separation, are applied. To reach this goal, an innovative sensing technique, based on the utilization of a HyperSpectral[b] I[/b]maging (HSI) device working in the SWIR region (1000-2500 nm), was investigated. Following this strategy, single polymers and/or mixed polymers recovered were correctly recognized. The main advantage of the proposed approach is linked to the possibility to perform "on-line" analyses, that is directly on the different material flow streams, as resulting from processing, without any physical sampling and classical laboratory "off-line" determination.
Iqbal, Nadeem; Assad, Salman; Rahat Aleman Bhatti, Joshua; Hasan, Aisha; Shabbir, Muhammad Usman; Akhter, Saeed
2016-09-29
To retrospectively evaluate the effectiveness of extracorporeal shock wave lithotripsy (ESWL) for urolithiasis and compare the results between children and adults. From January 2011 to January 2015 (four years), ESWL was performed in 104 children and 300 adults for urolithiasis. MODULITH ® SLX-F2 lithotripter (Storz Medical AG, Tägerwilen, Switzerland) equipment was used for ESWL. The stone-free rates, the number of ESWL sessions required, complication rates and ancillary procedures used were evaluated in a comparative manner. The mean age ± standard deviation (SD) of children was 7.84±4.22 years and of adults was a 40.22±1.57 years. Mean ± SD of the stone size was 1.28±61 cm in the adults while 1.08 ± 0.59 cm in the children. In adults, the complications included steinstrasse in six (1.98%) patients, fever in 15 (4.95%), hematuria in 19 (6.28%) and sepsis in six (1.98%) patients. In children, steinstrasse was observed in two (1.9%), mild fever in two (1.9%), hematuria in six (5.7%) and sepsis was seen in four (3.8%) patients. The overall complication rate in the adults and in the children, it was found to be 46/300 (15%) and in the children, it was seen to be 14/104 (13%). No statistical difference was found in post-ESWL complications between children and adults (P>0.05). Ancillary procedures including double J (DJ) stent were used in 13 (12.5%) children and 87 (29%) adults. There was a better stone clearance rate in children i.e. 79% as compared to 68% in adults ( X 2 : P=0.036). Children can achieve high stone-free rates after ESWL with a lower need for repeat ancillary procedures as compared to adults. However, there is a difference in the post-ESWL complications between these groups.
[Solitary stones of the lower renal calyx: how to treat?
Martov, A G; Ergakov, D V; Andronov, A S; Dutov, S V; Takhaev, R A; Kil'chukov, Z I; Moskalenko, S A
2017-06-01
The choice of treatment for the stones of the lower renal calyx is one of the challenging issues of modern urology. The aim of this retrospective and prospective study was to investigate the clinical effectiveness and safety of 3 modern minimally invasive techniques for treating renal stones: percutaneous (PNL) and transurethral (TNL) nephrolithotripsy and extracorporeal shock wave lithotripsy (ESWL) in patients with solitary lower calyx stones sized from 10 to 15 mm. The study included 136 patients with symptomatic stones of the lower calyces, who underwent ESWL, PNL and TNL from November 2010 to the present day. The criteria for inclusion in the study were: the presence of a solitary stone of the lower calyx, the stone size of 10 mm to 15 mm, the performance of the classical (standard) PNL in the prone position (puncture access 28-30 Fr) and the follow-up examination at 3 months after the operation. Forty-six patients underwent ESWL, 49 - PNL, and 41 - TNL. Postoperative follow-up was done at 3 months and included a plain radiography, ultrasound and non-contrast-enhanced computed tomography. The stone free rate (SFR) was used as a criterion for the effectiveness of the intervention, where the stone size of 3 mm was taken as the upper limit for the possible presence of fragments. Besides, the rate of repeat interventions, complications and subjective assessment of patients treatment satisfaction (0 to 10) by using visual analogue scale (VAS) were investigated. The effectiveness analysis of the three methods for treating the lower calyx stones sized 10-15 mm showed that PNL was no more effective than TNL (SFR 95.9% and 85.4%, respectively), but both methods were significantly more effective than ESWL (SFR 69.5%). 29.3% of patients who underwent TNL required repeat interventions (TNL or ESWL), while among those treated with ESWL, 45.6% required repeat ESWL sessions. PNL resulted in stone clearance in one stage. Postoperative inflammatory complications were most
Directory of Open Access Journals (Sweden)
Yuguan Hou
2016-01-01
Full Text Available Due to the fluctuation of the signal-to-noise ratio (SNR and the single snapshot case in the MIMO HF sky-wave radar system, the accuracy of the online estimation of the mutual coupling coefficients matrix of the uniform rectangle array (URA might be degraded by the classical approach, especially in the case of low SNR. In this paper, an Online Particle Mean-Shift Approach (OPMA is proposed, which is to get a relatively more effective estimation of the mutual coupling coefficients matrix with the low SNR. Firstly, the spatial smoothing technique combined with the MUSIC algorithm of URA is introduced for the DOA estimation of the multiple targets in the case of single snapshot which are taken as coherent sources. Then, based on the idea of the particle filter, the online particles with a moderate computational complexity are used to generate some different estimation results. Finally, the mean-shift algorithm is applied to get a more robust estimate of the equivalent mutual coupling coefficients matrix. The simulation results demonstrate the validity of the proposed approach in terms of the success probability, the statistics of bias, and the variance. The proposed approach is more robust and more accurate than the other two approaches.
Solitary magnetic perturbations at the ELM onset
Wenninger, R. P.; Zohm, H.; Boom, J. E.; Burckhart, A.; Dunne, M. G.; Dux, R.; Eich, T.; Fischer, R.; Fuchs, C.; Garcia-Munoz, M.; Igochine, V.; Hölzl, M.; Luhmann N., C., Jr.; Lunt, T.; Maraschek, M.; Müller, H. W.; Park, H. K.; Schneider, P. A.; Sommer, F.; Suttrop, W.; Viezzer, E.; the ASDEX Upgrade Team
2012-11-01
Tokamak H-mode plasmas frequently exhibit edge-localized modes (ELMs). ELMs allow maintaining sufficient plasma purity and thus enable stationary H-mode. On the other hand in a future device ELMs may cause divertor power flux densities far in excess of tolerable material limits. The size of the energy loss per ELM is determined by saturation effects in the non-linear phase of the ELM, which at present is hardly understood. ASDEX Upgrade is now equipped with a set of fast sampling diagnostics, which is well suited to investigate the chain of events around the ELM crash with appropriate temporal resolution (⩽10 µs). Solitary magnetic perturbations (SMPs) are identified as dominant features in the radial magnetic fluctuations below 100 kHz. They are typically observed close (±100 µs) to the onset of pedestal erosion. SMPs are field aligned structures rotating in the electron diamagnetic drift direction with perpendicular velocities of about 10 km s-1. A comparison of perpendicular velocities suggests that the perturbation evoking SMPs is located at or inside the separatrix. Analysis of very pronounced examples showed that the number of peaks per toroidal turn is 1 or 2, which is clearly lower than the corresponding numbers in linear stability calculations. In combination with strong peaking of the magnetic signals this results in a solitary appearance resembling modes like palm tree modes, edge snakes or outer modes. This behaviour has been quantified as solitariness and correlated with main plasma parameters. SMPs may be considered as a signature of the non-linear ELM phase originating at the separatrix or further inside. Thus they provide a handle to investigate the transition from linear to non-linear ELM phase. By comparison with data from gas puff imaging processes in the non-linear phase at or inside the separatrix and in the scrape-off layer (SOL) can be correlated. A connection between the passing of an SMP and the onset of radial filament propagation has
Solitary plasmacytoma of spine with amyloidosis
Directory of Open Access Journals (Sweden)
Cui-yun SUN
2017-01-01
Full Text Available Objective To report the diagnosis and treatment of one case of solitary plasmacytoma of spine with amyloidosis and investigate the clinicopathological features combined with literatures. Methods and Results The patient was a 46-year-old woman. She suffered from weakness of both lower limbs, unsteady gait and numbness of toes for 20 d. MRI examination revealed an irregular mass behind the spinal cord at T5-7 level and T6-7 vertebral body accessory. The enhanced MRI showed obvious heterogeneous enhancement. The border was clear and spinal dura mater was compressed to shift forward. During operation, T5-7 processus spinosus and vertebral laminae were eroded, and the cortex of bone showed "moth-eaten" erosion. The intraspinal and extradural lesion had rich blood supply, loose bone structure and intact spinal dura mater. Histologically, tumor cells were composed of intensive small cells, and focal plasmacytoid cells were seen. Flake pink staining substance was among them. Artificial cracks were common and multinuclear giant tumor cells were scatteredly distributed. Immunohistochemical analysis showed the cytoplasm of tumor cells were diffusely positive for CD138, CD38 and vimentin (Vim,scatteredly positive for leukocyte common antigen (LCA, and negative for immune globulin κ light chain(IgGκ and λ light chain (IgGλ, CD99, S-100 protein (S-100, pan cytokeratin (PCK, epithelial membrane antigen (EMA, HMB45 and CD34. The Ki-67 labeling index was 1.25%. Congo red staining showed the pink staining substance was brownish red. Hybridization in situ examination showed the DNA content of IgGκ was more than that of IgGλ. The final pathological diagnosis was solitary plasmacytoma of spine with amyloidosis. The patient was treated with postoperative chemotherapy, and there was no recurrence or metastasis during 18-month follow-up period. Conclusions Solitary plasmacytoma of spine with amyloidosis is a rare tumor. The imaging features can offer a few
Quantum positron acoustic waves
Energy Technology Data Exchange (ETDEWEB)
Metref, Hassina; Tribeche, Mouloud [Plasma Physics Group (PPG), Theoretical Physics Laboratory (TPL), Faculty of Physics, University of Bab-Ezzouar, USTHB, B.P. 32, El Alia, Algiers 16111 (Algeria)
2014-12-15
Nonlinear quantum positron-acoustic (QPA) waves are investigated for the first time, within the theoretical framework of the quantum hydrodynamic model. In the small but finite amplitude limit, both deformed Korteweg-de Vries and generalized Korteweg-de Vries equations governing, respectively, the dynamics of QPA solitary waves and double-layers are derived. Moreover, a full finite amplitude analysis is undertaken, and a numerical integration of the obtained highly nonlinear equations is carried out. The results complement our previously published results on this problem.
Solitary Plasmacytoma of the Chest Wall
Directory of Open Access Journals (Sweden)
Servet Kayhan
2014-03-01
Full Text Available A previously healthy 55-year-old man with right sided lateral chest pain admitted to clinic. It was found a solid and painful mass at the right 4th rib in physical examination. Chest X-ray and thoracic computarized tomography showed an opacity measured 60x33 mm within the right chest wall destructing the 4th rib. Needle aspiration was performed from tumor and cytologic examination showed atypic plasma cell infiltration. The patient was scheduled for a chest wall resection and reconstructive surgery. Examination of a permanent section showed that the chest wall tumor was solitary plasmacytoma. There was no evidence of multiple myeloma recurrence after two years from the operation.
A solitary fibrous tumor of the kidney
Directory of Open Access Journals (Sweden)
Anuruddha M Abeygunasekera
2015-01-01
Full Text Available A solitary fibrous tumor (SFT is an uncommon spindle cell neoplasm that usually occurs in the pleura, but may occur in extrapleural sites. Its occurrence in the kidney is rare. We report a SFT, clinically thought to be a renal cell carcinoma arising in the kidney of a 68-year-old female. The tumor was well-circumscribed and composed of a mixture of spindle cells and dense collagenous bands. Immunohistochemical studies revealed reactivity for CD34, CD99, and Bcl-2 protein, with no staining for keratin or muscle markers, confirming the diagnosis. The immunohistochemical study was the key to diagnosis. Several younger members of her family had colorectal and lung cancers suggesting the possibility of a familial or genetic susceptibility.
Benign solitary solid cold thyroid nodules
DEFF Research Database (Denmark)
Døssing, Helle; Bennedbaek, Finn Noe; Karstrup, Steen
2002-01-01
PURPOSE: To evaluate the effects of ultrasonography (US)-guided interstitial laser photocoagulation (ILP) on the volume of benign solitary solid cold thyroid nodules and any nodule-related symptoms. MATERIALS AND METHODS: ILP was performed in 16 patients with normal thyroid function and a solid...... benign thyroid nodule. None of the patients had uptake on a radionuclide scan. Patients underwent one ILP session. A needle was positioned in the thyroid nodule with US guidance, and the laser fiber was placed in the lumen of the needle. Patients were treated for 287-1,200 seconds with an output power...... of 1-3 W. ILP was performed with continuous US guidance and terminated when the echogenic changes were stationary. Thyroid nodule volume and thyroid function were evaluated before and 1, 3, and 6 months after treatment. During the same period, 15 untreated patients (control group) were followed up...
Formation of Tidal Captures and Gravitational Wave Inspirals in Binary-single Interactions
Energy Technology Data Exchange (ETDEWEB)
Samsing, Johan [Department of Astrophysical Sciences, Princeton University, Peyton Hall, 4 Ivy Lane, Princeton, NJ 08544 (United States); MacLeod, Morgan [School of Natural Sciences, Institute for Advanced Study, 1 Einstein Drive, Princeton, NJ 08540 (United States); Ramirez-Ruiz, Enrico [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
2017-09-01
We perform the first systematic study of how dynamical stellar tides and general relativistic (GR) effects affect the dynamics and outcomes of binary-single interactions. For this, we have constructed an N -body code that includes tides in the affine approximation, where stars are modeled as self-similar ellipsoidal polytropes, and GR corrections using the commonly used post-Newtonian formalism. Using this numerical formalism, we are able resolve the leading effect from tides and GR across several orders of magnitude in both stellar radius and initial target binary separation. We find that the main effect from tides is the formation of two-body tidal captures that form during the chaotic and resonant evolution of the triple system. The two stars undergoing the capture spiral in and merge. The inclusion of tides can thus lead to an increase in the stellar coalescence rate. We also develop an analytical framework for calculating the cross section of tidal inspirals between any pair of objects with similar mass. From our analytical and numerical estimates, we find that the rate of tidal inspirals relative to collisions increases as the initial semimajor axis of the target binary increases and the radius of the interacting tidal objects decreases. The largest effect is therefore found for triple systems hosting white dwarfs and neutron stars (NSs). In this case, we find the rate of highly eccentric white dwarf—NS mergers to likely be dominated by tidal inspirals. While tidal inspirals occur rarely, we note that they can give rise to a plethora of thermonuclear transients, such as Ca-rich transients.
Formation of Tidal Captures and Gravitational Wave Inspirals in Binary-single Interactions
International Nuclear Information System (INIS)
Samsing, Johan; MacLeod, Morgan; Ramirez-Ruiz, Enrico
2017-01-01
We perform the first systematic study of how dynamical stellar tides and general relativistic (GR) effects affect the dynamics and outcomes of binary-single interactions. For this, we have constructed an N -body code that includes tides in the affine approximation, where stars are modeled as self-similar ellipsoidal polytropes, and GR corrections using the commonly used post-Newtonian formalism. Using this numerical formalism, we are able resolve the leading effect from tides and GR across several orders of magnitude in both stellar radius and initial target binary separation. We find that the main effect from tides is the formation of two-body tidal captures that form during the chaotic and resonant evolution of the triple system. The two stars undergoing the capture spiral in and merge. The inclusion of tides can thus lead to an increase in the stellar coalescence rate. We also develop an analytical framework for calculating the cross section of tidal inspirals between any pair of objects with similar mass. From our analytical and numerical estimates, we find that the rate of tidal inspirals relative to collisions increases as the initial semimajor axis of the target binary increases and the radius of the interacting tidal objects decreases. The largest effect is therefore found for triple systems hosting white dwarfs and neutron stars (NSs). In this case, we find the rate of highly eccentric white dwarf—NS mergers to likely be dominated by tidal inspirals. While tidal inspirals occur rarely, we note that they can give rise to a plethora of thermonuclear transients, such as Ca-rich transients.
Solitary Rectal Ulcer Syndrome: A Biopsychosocial Assessment
Directory of Open Access Journals (Sweden)
Hamed Daghaghzadeh
2016-06-01
Full Text Available Background: Solitary rectal ulcer syndrome (SRUS is a chronic disorder of the gastrointestinal tract and its etiology is not well understood. There is no specific treatment for this syndrome and patients with SRUS may, for years, experience many complications. The aim of the present research was the biopsychosocial study of patients with SRUS.Methods: The study participants consisted of 16 patients with SRUS (7 men and 9 women. Their medical records were reviewed retrospectively to evaluate the clinical spectrum of the patients along with the endoscopic and histological findings. Moreover, psychiatric and personality disorders [based on Diagnostic and Statistical Manual of Mental Disorders, 4th ed, Text Revision (DSM IV-TR], psychosocial stressors, early life traumas, and coping mechanisms were assessed through structured interviews.Results: At presentation, mean age of the patients was 39 years (16 to 70. Common symptoms reported included rectal bleeding (93.8%, rectal self-digitations (81.2%, passage of mucous (75%, anal pain (75%, and straining (75%. Endoscopically, solitary and multiple lesions were present in 9 (60% and 4 (26.7% patients, respectively, and 87% of lesions were ulcerative and 13.3% polypoidal. The most common histological findings were superficial ulceration (92.85% and intercryptic fibromuscular obliteration (87.71%. Common psychosocial findings included anxiety disorders (50%, depression (37.5%, obsessive-compulsive personality disorder (OCPD or traits (62.5%, interpersonal problems (43.75%, marital conflicts (43.75%, occupational stress (37.5%, early life traumas, physical abuse (31.25%, sexual abuse (31.25%, dysfunctional coping mechanisms, emotional inhibition (50%, and non-assertiveness (37.5%.Conclusion: Given the evidence in this study, we cannot ignore the psychosocial problems of patients with SRUS and biopsychosocial assessment of SRUS is more appropriate than biomedical evaluation alone.
Widespread occurrence of honey bee pathogens in solitary bees.
Ravoet, Jorgen; De Smet, Lina; Meeus, Ivan; Smagghe, Guy; Wenseleers, Tom; de Graaf, Dirk C
2014-10-01
Solitary bees and honey bees from a neighbouring apiary were screened for a broad set of putative pathogens including protists, fungi, spiroplasmas and viruses. Most sampled bees appeared to be infected with multiple parasites. Interestingly, viruses exclusively known from honey bees such as Apis mellifera Filamentous Virus and Varroa destructor Macula-like Virus were also discovered in solitary bees. A microsporidium found in Andrena vaga showed most resemblance to Nosema thomsoni. Our results suggest that bee hives represent a putative source of pathogens for other pollinators. Similarly, solitary bees may act as a reservoir of honey bee pathogens. Copyright © 2014 Elsevier Inc. All rights reserved.
Solitary fibrous tumor of the orbit with intracranial involvement.
Young, Thomas K; Hardy, Thomas G
2011-01-01
Solitary fibrous tumor of the orbit is a rare neoplasm that often follows a benign course. Additional involvement beyond the orbit is even rarer, having only been reported in 2 cases previously. The authors describe a 62-year-old patient with a primarily intracranial lesion including orbital extension which was debulked and initially diagnosed as meningioma. Two recurrences 3 and 4 years later disclosed a solitary fibrous tumor, with the initial histopathology being revised to the same diagnosis. This rare presentation of an orbital solitary fibrous tumor highlights the surgical challenge faced when the tumor straddles the cranio-orbital junction and demonstrates the potential for rapid regrowth after incomplete excision.
Stothard, David; Lindsay, Ian; Dunn, Malcolm
2004-02-09
We demonstrate a PPLN based pump-enhanced, singly-resonant optical parametric oscillator configured in a traveling wave geometry and pumped by a Ti:sapphire laser. The inclusion of a low finesse etalon within the OPO cavity stabilizes the signal frequency, and rotation of the etalon allows this frequency to be systematically hopped from axial mode to nearest neighbor axial mode over the entire free spectral range of the etalon (83GHz). Tuning of the pump frequency allows the signal frequency to be smoothly tuned over a cavity free spectral range. More than 35mW of single frequency idler power was generated in the spectral range 2800-3000nm for 600mW pump power. The superiority of traveling wave over standing wave geometries in these regards is discussed.
Tomotani, Barbara Mizumo; Amaya, Juan Pablo; Oda, Gisele Akemi; Valentinuzzi, Veronica Sandra
2016-01-01
Abstract South American subterranean rodents are mainly described as solitary and mutual synchronization was never observed among individuals maintained together in laboratory. We report that a single birth event was capable of disrupting the robust nocturnal activity rhythm of singly housed
Co-periodic stability of periodic waves in some Hamiltonian PDEs
Benzoni-Gavage, S.; Mietka, C.; Rodrigues, L. M.
2016-10-01
The stability of periodic traveling wave solutions to dispersive PDEs with respect to ‘arbitrary’ perturbations is still widely open. The focus is put here on stability with respect to perturbations of the same period as the wave, for KdV-like systems of one-dimensional Hamiltonian PDEs. Stability criteria are derived and investigated first in a general abstract framework, and then applied to three basic examples that are very closely related, and ubiquitous in mathematical physics, namely, a quasilinear version of the generalized Korteweg-de Vries equation (qKdV), and the Euler-Korteweg system in both Eulerian coordinates (EKE) and in mass Lagrangian coordinates (EKL). Those criteria consist of a necessary condition for spectral stability, and of a sufficient condition for orbital stability. Both are expressed in terms of a single function, the abbreviated action integral along the orbits of waves in the phase plane, which is the counterpart of the solitary waves moment of instability introduced by Boussinesq. Regarding solitary waves, the celebrated Grillakis-Shatah-Strauss stability criteria amount to looking for the sign of the second derivative of the moment of instability with respect to the wave speed. For periodic waves, the most striking results obtained here can be summarized as: an odd value for the difference between N—the size of the PDE system—and the negative signature of the Hessian of the action implies spectral instability, whereas a negative signature of the same Hessian being equal to N implies orbital stability. Since these stability criteria are merely encoded by the negative signature of matrices, they can at least be checked numerically. Various numerical experiments are presented, which clearly discriminate between stable cases and unstable cases for (qKdV), (EKE) and (EKL).
Genetic relatedness of low solitary nests of Apis dorsata from Marang, Terengganu, Malaysia.
Directory of Open Access Journals (Sweden)
Najmeh Sahebzadeh
Full Text Available Knowledge on the population of genetic structure and ecological behaviour of Apis dorsata from Peninsular Malaysia is needed for effective management and conservation of this species since unsustainable whole solitary low nest cutting for product harvesting is the current common practice here. The analysis of 15 single locus DNA microsatellite markers on samples from 20 solitary nests of A. dorsata showed that while these markers were polymorphic, high intracolonial relatedness existed. Furthermore, in general, slightly negative values of intercolony relatedness (R among the nests of A. dorsata were found. However, positive values of mean intercolony relatedness were observed between 54 pairs of nests out of 190 possible combinations. The R values among nest pairs 3-4 and 3-5 was higher than 0.50 showing that their queens were half siblings, whereas nest pair 19-20 showed relatedness of 0.95 indicating that the same queen was sampled. The results that we obtained could not conclusively support the hypothesis of this study that the honey hunters in Marang district of Malaysia repeatedly harvest the same nest located at a different site and at a different time during the same honey harvesting season. However, our finding of an appreciable level of intercolonial relatedness between several pairs of nests in this pioneer study indicated that a comprehensive study with a larger sample size of solitary nests found throughout the region would be necessary to provide concrete proof for this novel idea.
Directory of Open Access Journals (Sweden)
Weiguo Rui
2014-01-01
Full Text Available By using the integral bifurcation method together with factoring technique, we study a water wave model, a high-order nonlinear wave equation of KdV type under some newly solvable conditions. Based on our previous research works, some exact traveling wave solutions such as broken-soliton solutions, periodic wave solutions of blow-up type, smooth solitary wave solutions, and nonsmooth peakon solutions within more extensive parameter ranges are obtained. In particular, a series of smooth solitary wave solutions and nonsmooth peakon solutions are obtained. In order to show the properties of these exact solutions visually, we plot the graphs of some representative traveling wave solutions.
Samsing, Johan; MacLeod, Morgan; Ramirez-Ruiz, Enrico
2018-02-01
We present a study of binary–single interactions with energy-loss terms such as tidal dissipation and gravitational-wave (GW) emission added to the equation of motion. The inclusion of such terms leads to the formation of compact binaries that form during the three-body interaction through two-body captures. These binaries predominantly merge relatively promptly at high eccentricity, with several observable and dynamical consequences to follow. Despite their possibility for being observed in both present and upcoming transient surveys, their outcomes are not firmly constrained. In this paper, we present an analytical framework that allows to estimate the cross section of such two-body captures, which permits us to study how the corresponding rates depend on the initial orbital parameters, the mass hierarchy, the type of interacting object, and the energy dissipation mechanism. This formalism is applied here to study the formation of two-body GW captures, for which we estimate absolute and relative rates relevant to Advanced LIGO detections. It is shown that two-body GW captures should have compelling observational implications if a sizable fraction of detected compact binaries are formed via dynamical interactions.
Solitary osteochondroma arising from cervical spina bifida occulta.
Ofluoglu, Ali Ender; Abdallah, Anas; Gokcedag, Akin
2013-01-01
Solitary osteochondromas are common benign long bone tumors originating from cartilage. They may produce a wide variety of symptoms and complications depending on their spinal location. These may include compressive myelopathy, nerve root compression, pathologic fracture and malignant degeneration, or in some cases only pain. Solitary cervical spine osteochondromas have been reported mostly in the neural arch or vertebral body. This report describes a patient presenting with neck pain, with a benign osteochondroma arising in the right bifid C5 lamina.
[Adenocarcinoma of lung cancer with solitary metastasis to the stomach].
Koh, Sung Ae; Lee, Kyung Hee
2014-09-25
Although hematogenous metastasis of cancer to the gastrointestinal track is rare, it sometime has been reported in patients with malignant melanoma and breast cancer. However, it is extremely rare for lung cancer to metastasize to the stomach, not to mention solitary gastric metastasis. Herein, the authors report a case of a 69-year-old man who was initially diagnosed with lung cancer with synchronous primary gastric cancer which proved to be lung cancer with solitary gastric metastasis after the operation.
Reducing the use and impact of solitary confinement in corrections.
Ahalt, Cyrus; Haney, Craig; Rios, Sarah; Fox, Matthew P; Farabee, David; Williams, Brie
2017-03-13
Purpose Although the reform of solitary confinement is underway in many jurisdictions around world, isolation remains in widespread use in many jails and prisons. The purpose of this paper is to discuss opportunities for reform in the USA that could also be applied globally. Design/methodology/approach A review of the evidence on solitary confinement policies and practices in the USA to develop recommendations for reform with global application. Findings Focusing on this evidence, the authors argue that solitary confinement is overused and recommend a multi-level approach available to correctional systems worldwide including: immediately limiting solitary confinement to only those cases in which a violent behavioral infraction has been committed for which safety cannot otherwise be achieved, ensuring the briefest terms of isolation needed to achieve legitimate and immediate correctional goals, prohibiting its use entirely for some populations, regularly reviewing all isolated prisoners for as-soon-as-possible return to general population, including the immediate return of those showing mental and physical health risk factors, assisting individuals who are transitioning out of isolation (either to the general population or to the community), and partnering with medical, public health, and criminal justice experts to develop evidence-based alternatives to solitary confinement for nearly all prisoners. Originality/value This paper provides an overview of the evidence supporting an overhaul of solitary confinement policy in the USA and globally where solitary confinement remains in wide use and offers recommendations for immediate steps that can be taken toward achieving evidence-based solitary confinement reform.
Spontaneous Remission of Solitary-Type Infantile Myofibromatosis
Directory of Open Access Journals (Sweden)
Kazuhiro Kikuchi
2011-08-01
Full Text Available Infantile myofibromatosis is a rare fibrous tumor of infancy. The cutaneous solitary type has typically an excellent prognosis. However, histologically, it is important to rule out leiomyosarcoma, which has a poor prognosis. The low frequency of mitosis was definitive for a diagnosis of infantile myofibromatosis. We present a cutaneous solitary-type case of infantile myofibromatosis. Following incisional biopsy, the tumor remitted spontaneously.
THE STUDY OF CLINICAL PRESENTATION OF SOLITARY NODULE THYROID
Directory of Open Access Journals (Sweden)
Lakshmikanthan Premalatha
2017-07-01
Full Text Available BACKGROUND Thyroid disorders are the most common endocrine disorder seen in clinical practice and solitary thyroid nodule is one of the common presentations of thyroid disease. A discrete swelling in an otherwise impalpable gland is termed isolated or solitary nodule of thyroid.1 The prevalence of thyroid nodule increases from near zero at 15 years to 50% by about 60 to 65 years on sonography. At most 10% of these nodules are palpable even by experienced clinicians. This study is about the clinical presentation, histopathology and management of solitary nodule thyroid in MGM GH Tiruchirappalli. AIMS AND OBJECTIVES- To determine the age and sex incidence among the cases of solitary nodule thyroid. To study the percentage of euthyroid, hypothyroid or hyperthyroid state in patients presenting with solitary nodule thyroid. To study the proportion of malignant and benign cases among the solitary nodule thyroid at M.G.M. Govt. Hospital, Tiruchirappalli. MATERIALS AND METHODS This study includes 58 cases of solitary nodule of thyroid noted during the period Jan 2016-Dec 2016. Factors were tabulated and analysed statistically. RESULTS From the present study, the mean age at presentation found to be 42.5 years with preponderance to females. Because of periods of fluctuations in the demands of the hormonal requirement in female in their life cycle (puberty, menstrual cycles, pregnancy, menopause, the chances of thyroid nodule formation are very high as compared with male counterparts. From the study, distribution of malignancy is about 10.34. The incidence of malignancy found to be 12%, sensitivity is 87.5%, specificity is 100% for FNAC and HPE. CONCLUSION Majority of the patients are between 30-49 years of age. Incidence of solitary thyroid nodule is more common in female. Female: male ratio is almost about 15:1 Commonest symptom is swelling over anterior or lateral aspect of neck Among the benign lesion dominant nodule is most common and papillary and
Solitary necrotic nodule of the liver: parasitic origin?
Tsui, W. M.; Yuen, R. W.; Chow, L. T.; Tse, C. C.
1992-01-01
AIMS: To report further cases of solitary necrotic nodule of the liver and to study its nature. METHODS: Seven nodules were retrieved from 4000 necropsy and surgical liver specimens coming to light over the past five years. All of them satisfied the diagnostic criteria of solitary necrotic nodule: a solid lesion with a central necrotic core and a hyalinised fibrotic capsule containing elastic fibres. Their clinicopathological features were reviewed. RESULTS: The nodules were incidental findin...
Juvenile polyps: recurrence in patients with multiple and solitary polyps.
Fox, Victor L; Perros, Stephen; Jiang, Hongyu; Goldsmith, Jeffrey D
2010-09-01
Juvenile polyps are benign hamartomas with neoplastic potential that are the most frequent gastrointestinal polyp of childhood. Most information about juvenile polyps in childhood comes from small published series that lack detailed outcome data. We sought to identify a large cohort of children with one or more polyps and analyze clinical characteristics, including polyp recurrence, which might contribute to the development of management guidelines. A retrospective chart review study of patients with juvenile polyps of the colon was performed. Cases were identified by searching a single hospital pathology database from 1990 to 2009 for the diagnosis of juvenile polyps. Recorded information included basic demographics, family history, genetic testing, and colonoscopy and pathology reports. A total of 257 children (median age, 5.6 y; 61.5% male) with juvenile polyps were identified. Among 192 patients who underwent complete colonoscopy at initial diagnosis, 117 (60.9%) had a single polyp, 75 (39.1%) had multiple polyps, 8 (4.2%) had polyps restricted to the right colon, and a total of 1653 polyps were found during 350 colonoscopy examinations. Polyps recurred in 21 of 47 (44.7%) patients after initial eradication, including 3 (16.7%) of 18 presenting with a single polyp. Neoplasia was found in 10 of 257 (3.9%) patients (right colon in 7 patients). Germline DNA abnormalities in mothers against decapentaplegic Drosophila (SMAD4), bone morphogenetic protein receptor 1A (BMPR1A), and phosphatase and tensin homolog (PTEN) were detected in 10 of 23 (43.5%) patients with multiple polyps. Recurrent polyp formation is common in children with juvenile polyps and occurs in patients with multiple and solitary polyps. Standardized protocols for detecting polyp recurrence, associated gene mutations, and neoplasia should be developed for children with juvenile polyps. Copyright 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.
Comparison of solitary cerebral metastasis and glioblastoma multiform
International Nuclear Information System (INIS)
Kim, Hyun Cheol; Choi, Woo Suk; Kim, Eui Jong; Oh, Joo Hyeong; Yoon, Yup
1996-01-01
The purpose of this study is to evaluate the MR images of solitary cerebral metastasis and glioblastoma multiform to determine the differential findings. Ten cases of solitary cerebral metastasis and 14 cases of glioblastoma multiform were retrospectively reviewed, all of which were proved by pathologically. The MR findings were compared in regard to tumor size and location, degree of edema, enhancement pattern, and shape of rime enhancement. Mean maximum diameter or solitary cerebral metastasis was 3.85 cm(s.d. 1.47). Metastatic lesions were located in corticomedullary junction(70%) with cerebellum in 2 cases. The locations of glioblastoma multiform were white matter(64%) without cerebellar involvement and the mean maximum diameter was 5.43 cm(s.d. 0.99). In solitary cerebral metastasis, the size of edema was larger than the tumor diameter in 50%, but glioblastoma multiform did not show severe degree of edema. Rim enhancement seen in 7 cases of solitary cerebral metastasis showed unilocular shape and complete rim in 6 cases, and even thickness and smooth inner margine in 5 cases. However, rim enhancement seen in 11 cases of glioblastoma multiform showed multilocular appearance with septa in all cases, incomplete rim in 5 cases, and uneven thickness and irregular inner margin in 10 cases. Tumor location, degree of edema, and rim enhancement pattern on Gd-enhanced MR may be useful in differentiation between solitary cerebral metastasis and glioblastoma multiform
TRPM5-expressing solitary chemosensory cells respond to odorous irritants.
Lin, Weihong; Ogura, Tatsuya; Margolskee, Robert F; Finger, Thomas E; Restrepo, Diego
2008-03-01
Inhaled airborne irritants elicit sensory responses in trigeminal nerves innervating the nasal epithelium, leading to protective reflexes. The sensory mechanisms involved in the detection of odorous irritants are poorly understood. We identified a large population of solitary chemosensory cells expressing the transient receptor potential channel M5 (TRPM5) using transgenic mice where the promoter of TRPM5 drives the expression of green fluorescent protein (GFP). Most of these solitary chemosensory cells lie in the anterior nasal cavity. These GFP-labeled solitary chemosensory cells exhibited immunoreactivity for synaptobrevin-2, a vesicle-associated membrane protein important for synaptic transmission. Concomitantly, we found trigeminal nerve fibers apposed closely to the solitary chemosensory cells, indicating potential transmission of sensory information to trigeminal fibers. In addition, stimulation of the nasal cavity with high concentrations (0.5-5 mM) of a variety of odorants elicited event-related potentials (ERPs) in areas rich in TRPM5-expressing solitary chemosensory cells. Furthermore, odorous chemicals and trigeminal stimuli induced changes in intracellular Ca(2+) levels in isolated TRPM5-expressing solitary chemosensory cells in a concentration-dependent manner. Together, our data show that the TRPM5-expressing cells respond to a variety of chemicals at high exposure levels typical of irritants and are positioned in the nasal cavity appropriately to monitor inhaled air quality.
International Nuclear Information System (INIS)
Luo Hongying; Liu Jun; Wang Chuanjian; Dai Zhengde
2013-01-01
Painlevé integrability has been tested for (2+1)D Boussinesq equation with disturbance term using the standard WTC approach after introducing the Kruskai's simplification. New breather solitary solutions depending on constant equilibrium solution are obtained by using Extended Homoclinic Test Method. Moreover, the spatiotemporal feature of breather solitary wave is exhibited. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
Nonlinear localized dust acoustic waves in a charge varying dusty plasma with nonthermal ions
International Nuclear Information System (INIS)
Tribeche, Mouloud; Amour, Rabia
2007-01-01
A numerical investigation is presented to show the existence, formation, and possible realization of large-amplitude dust acoustic (DA) solitary waves in a charge varying dusty plasma with nonthermal ions. These nonlinear localized structures are self-consistent solutions of the collisionless Vlasov equation with a population of fast particles. The spatial patterns of the variable charge DA solitary wave are significantly modified by the nonthermal effects. The results complement and provide new insights into previously published results on this problem
Directory of Open Access Journals (Sweden)
M. Arshad
Full Text Available In this manuscript, we constructed different form of new exact solutions of generalized coupled Zakharov–Kuznetsov and dispersive long wave equations by utilizing the modified extended direct algebraic method. New exact traveling wave solutions for both equations are obtained in the form of soliton, periodic, bright, and dark solitary wave solutions. There are many applications of the present traveling wave solutions in physics and furthermore, a wide class of coupled nonlinear evolution equations can be solved by this method. Keywords: Traveling wave solutions, Elliptic solutions, Generalized coupled Zakharov–Kuznetsov equation, Dispersive long wave equation, Modified extended direct algebraic method
Dal Moro, Giancarlo; Moustafa, Sayed S. R.; Al-Arifi, Nassir S.
2018-01-01
Rayleigh waves often propagate according to complex mode excitation so that the proper identification and separation of specific modes can be quite difficult or, in some cases, just impossible. Furthermore, the analysis of a single component (i.e., an inversion procedure based on just one objective function) necessarily prevents solving the problems related to the non-uniqueness of the solution. To overcome these issues and define a holistic analysis of Rayleigh waves, we implemented a procedure to acquire data that are useful to define and efficiently invert the three objective functions defined from the three following "objects": the velocity spectra of the vertical- and radial-components and the Rayleigh-wave particle motion (RPM) frequency-offset data. Two possible implementations are presented. In the first case we consider classical multi-offset (and multi-component) data, while in a second possible approach we exploit the data recorded by a single three-component geophone at a fixed offset from the source. Given the simple field procedures, the method could be particularly useful for the unambiguous geotechnical exploration of large areas, where more complex acquisition procedures, based on the joint acquisition of Rayleigh and Love waves, would not be economically viable. After illustrating the different kinds of data acquisition and the data processing, the results of the proposed methodology are illustrated in a case study. Finally, a series of theoretical and practical aspects are discussed to clarify some issues involved in the overall procedure (data acquisition and processing).
Food searching and superparasitism in solitary parasitoids
Sirot, Etienne; Bernstein, Carlos
Optimality theory predicts that, provided that a larva resulting from superparasitism has some chance of winning the competition with the other larvae present in the host, under certain conditions, solitatry parasitoids should resort to superparasitism. Both theoretical and experimental studies have shown that the life expectancy of the parasitoid has a strong influence on the decision to reject or to accept superparasitism. In many species, life expectancy on its turn depends on the feeding behaviour of the parasitoids, which have to forage for non-host food (mainly plant materials), for the maintenance of their energy reseves. As many solitary parasitoids do not find non-host food in their host patches, they have to choose at each instant whether to search for food or to search for hosts. In this paper, we develop a stochastic dynamic programming model to study the behavioural choice between host and food searching, and its consequences for the acceptance and rejection of superparasitism. We study the influence of habitat quality and parasitoid physiological state on the optimal choice. The model predicts that the crucial point determining the optimal strategy is the balance between egg-and time-limitation.
Guideline on management of solitary pulmonary nodule.
Álvarez Martínez, Carlos J; Bastarrika Alemañ, Gorka; Disdier Vicente, Carlos; Fernández Villar, Alberto; Hernández Hernández, Jesús R; Maldonado Suárez, Antonio; Moreno Mata, Nicolás; Rosell Gratacós, Antoni
2014-07-01
The aim of the proposed recommendations is be a tool to facilitate decision-making in patients with a solitary pulmonary nodule (SPN). For an optimal decision, accessibility to the different diagnostics techniques and patient preferences need to be incorporated. The first assessment, which includes a chest computed tomography scan, separates a group of patients with extrapulmonary neoplasm or a high surgical risk who require individualized management. Another two groups of patients are patients with SPN up to 8mm and those who have a subsolid SPN, for which specific recommendations are established. SPN larger than 8mm are classified according to their probability of malignancy into low (less than 5%), where observation is recommended, high (higher than 65%), which are managed with a presumptive diagnosis of localized stage carcinoma, and intermediate, where positron emission tomography-computed tomography has high yield for reclassifying them into high or low probability. In cases of intermediate or high probability of malignancy, transbronchial needle aspiration or biopsy of the nodule may be an option. Radiologic observation with low radiation computed tomography without contrast is recommended in SPN with low probability of malignancy, and resection with videothoracoscopy in undiagnosed cases with intermediate or high probability of malignancy. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.
Solid solitary hamartoma of the spleen
Directory of Open Access Journals (Sweden)
Grubor Nikica
2013-01-01
Full Text Available Introduction. Hamartoma of the spleen is a rare, sometimes asymptomatic similar to hemangioma benign tumor of the spleen, which, owing to the new diagnostic imaging methods, is discovered with increasing frequency. It appears as solitary or multiple tumorous lesions. Case Outline. We present a 48-year-old woman in whom, during the investigation for Helicobacter pylori gastric infection and rectal bleeding, with ultrasonography, a mass 6.5×6.5 cm in diameter was discovered by chance within the spleen. Splenectomy was performed due to suspected lymphoma of the spleen. On histology, tumor showed to be of mixed cellular structure, with areas without white pulp, at places with marked dilatation of sinusoids and capillaries to the formation of „blood lakes“ between which broad hypercellular Billroth’s zones were present. Extramedullary hematopoiesis was found focally. The cells that covered vascular spaces were CD34+ and CD31+ and CD8- and CD21-. Conclusion. Hamartoma has to be taken into consideration always when well circumscribed hypervascular tumor within the spleen is found, particularly in children. Although the diagnosis of hamartoma may be suspected preoperatively, the exact diagnosis is established based on histological and immunohystochemistry examinations. Treatment is most often splenectomy and rarely a partial splenectomy is possible, which is recommended particularly in children.
TERT promoter mutations and prognosis in solitary fibrous tumor.
Bahrami, Armita; Lee, Seungjae; Schaefer, Inga-Marie; Boland, Jennifer M; Patton, Kurt T; Pounds, Stanley; Fletcher, Christopher D
2016-12-01
Solitary fibrous tumor is a mesenchymal neoplasm exhibiting a broad spectrum of biological behavior and harboring the NAB2-STAT6 fusion. Clinicopathologic parameters are currently used in risk-prediction models for solitary fibrous tumor, but the molecular determinants of malignancy in solitary fibrous tumors remain unknown. We proposed that the activation of telomere maintenance pathways confers a perpetual malignant phenotype to these tumors. Therefore, we investigated telomerase reverse transcriptase (TERT) reactivation induced by promoter mutations as a potential molecular mechanism for aggressive clinical behavior in solitary fibrous tumor. The retrospective study included tumor samples from 94 patients with solitary fibrous tumor (31 thoracic and 63 extra-thoracic). Follow-up information was available for 68 patients (median, 46 months). TERT promoter mutation analysis was performed by PCR and Sanger sequencing, and TERT mRNA expression was assessed by real-time quantitative reverse transcription PCR. Patients were stratified into clinicopathologic subgroups (high-risk (n=20), moderate-risk (n=28), and low-risk (n=46)) according to the risk-stratification model proposed by Demicco et al. TERT promoter mutations were identified in 26 of 94 (28%) solitary fibrous tumors: -124C>T in 23 tumors (88%), -124C>A in 1 tumor (4%), and -146C>T in 2 tumors (8%). Real-time quantitative reverse transcription PCR revealed that TERT mRNA expression was higher in all solitary fibrous tumors with the mutant TERT promoter than those with the wild-type TERT promoter. TERT promoter mutations were strongly associated with high-risk clinicopathologic characteristics and outcome. An adverse event (relapse, death) occurred in 16 of 68 (24%) patients, 12 with solitary fibrous tumors with TERT promoter mutations and 4 with the wild-type TERT promoter. TERT promoter mutations were strongly associated with older age (P=0.006), larger tumor size (P=0.000002), higher risk classifications
Real-time computed tomography fluoroscopy-guided solitary lung tumor model in a rabbit.
Choi, Byeong Hyeon; Young, Hwan Seok; Quan, Yu Hua; Rho, Ji Yun; Eo, Jae Seon; Han, Kook Nam; Choi, Young Ho; Kim, Hyun Koo
2017-01-01
Preclinical studies of lung cancer require suitable large-animal models to allow evaluation and development of surgical and interventional techniques. We assessed the feasibility and safety of a novel rabbit lung cancer model of solitary tumors, in which real-time computed tomography fluoroscopy is used to guide inoculation of VX2 carcinoma single-cell suspensions. Thirty-eight rabbits were divided into four groups according to the volume of the VX2 tissue or cell suspension, the volume of lipiodol, the volume of Matrigel, and the injection needle size. The mixtures were percutaneously injected into rabbit lungs under real-time computed tomography fluoroscopy guidance. Two weeks later, VX2 lung carcinomas were confirmed via positron emission tomography/computed tomography, necropsy, and histology. Real-time computed tomography fluoroscopy allowed the precise inoculation of the tumor cell suspensions containing lipiodol, while the use of Matrigel and a small needle prevented leakage of the suspensions into the lung parenchyma. Solitary lung tumors were successfully established in rabbits (n = 22) inoculated with single-cell suspensions (150 μL), lipiodol (150 μL), and Matrigel (150 μL) using a 26-gauge needle. This combination was determined to be optimal. Pneumothorax was observed in only two of the 38 rabbits (5.3%), both of which survived to the end of the study without any intervention. Real-time computed tomography fluoroscopy-guided inoculation of VX2 single-cell suspensions with lipiodol and Matrigel using a small needle is an easy and safe method to establish solitary lung tumors in rabbits.
Success of electromagnetic shock wave lithotripter asmonotherapy ...
African Journals Online (AJOL)
Objectives: To evaluate the success of shock wave lithotripsy (SWL) as monotherapy for solitary renalstones larger than 2 cm without ureteral stenting. Hence, if our study result demonstrates acceptable successand safety, we can recommend ESWL as a treatment option for patients with large renal calculi. Subjects and ...
New exact wave solutions for Hirota equation
Indian Academy of Sciences (India)
than other traditional techniques. The study indicates the validity and great potential of the first integral method in solving complicated solitary wave problems. References. [1] W M Taha, M S M Noorani and I Hashim, J. King Saud University-Science 26, 75 (2014). [2] G Ebadi and A Biswas, Commun. Nonlinear Sci. Numer.
The Role of Nuclear Medicine in The Diagnosis and Management of Solitary Pulmonary Nodules
Directory of Open Access Journals (Sweden)
Farzaneh Shariati
2013-10-01
Full Text Available Solitary pulmonary nodule (SPN is a frequent finding on the chest x-ray and computed tomography. Nuclear medicine techniques play an important role in the diagnosis and management of SPN. In the current review, we briefly will explain the different nuclear medicine modalities in this regard including positron emission tomography (PET using 18-F-FDG, and 11-C-Methionine, and single photon emission computerized tomography (SPECT using somatostatin receptor scintigraphy, 201-Thallium, and 99m-Tc-MIBI.
Solitary Candida albicans Infection Causing Fournier Gangrene and Review of Fungal Etiologies.
Perkins, Tiffany A; Bieniek, Jared M; Sumfest, Joel M
2014-01-01
Polymicrobial bacterial infections are commonly found in cases of Fournier gangrene (FG), although fungal growth may occur occasionally. Solitary fungal organisms causing FG have rarely been reported. The authors describe a case of an elderly man with a history of diabetes who presented with a necrotizing scrotal and perineal soft tissue infection. He underwent emergent surgical debridement with findings of diffuse urethral stricture disease and urinary extravasation requiring suprapubic tube placement. Candida albicans was found to be the single causative organism on culture, and the patient recovered well following antifungal treatment. Fungal infections should be considered as rare causes of necrotizing fasciitis and antifungal treatment considered in at-risk immunodeficient individuals.
From solitons to rogue waves in nonlinear left-handed metamaterials.
Shen, Yannan; Kevrekidis, P G; Veldes, G P; Frantzeskakis, D J; DiMarzio, D; Lan, X; Radisic, V
2017-03-01
In the present work, we explore soliton and roguelike wave solutions in the transmission line analog of a nonlinear left-handed metamaterial. The nonlinearity is expressed through a voltage-dependent, symmetric capacitance motivated by recently developed ferroelectric barium strontium titanate thin-film capacitor designs. We develop both the corresponding nonlinear dynamical lattice and its reduction via a multiple scales expansion to a nonlinear Schrödinger (NLS) model for the envelope of a given carrier wave. The reduced model can feature either a focusing or a defocusing nonlinearity depending on the frequency (wave number) of the carrier. We then consider the robustness of different types of solitary waves of the reduced model within the original nonlinear left-handed medium. We find that both bright and dark solitons persist in a suitable parametric regime, where the reduction to the NLS model is valid. Additionally, for suitable initial conditions, we observe a rogue wave type of behavior that differs significantly from the classic Peregrine rogue wave evolution, including most notably the breakup of a single Peregrine-like pattern into solutions with multiple wave peaks. Finally, we touch upon the behavior of generalized members of the family of the Peregrine solitons, namely, Akhmediev breathers and Kuznetsov-Ma solitons, and explore how these evolve in the left-handed transmission line.
Bifurcations of traveling wave solutions for an integrable equation
International Nuclear Information System (INIS)
Li Jibin; Qiao Zhijun
2010-01-01
This paper deals with the following equation m t =(1/2)(1/m k ) xxx -(1/2)(1/m k ) x , which is proposed by Z. J. Qiao [J. Math. Phys. 48, 082701 (2007)] and Qiao and Liu [Chaos, Solitons Fractals 41, 587 (2009)]. By adopting the phase analysis method of planar dynamical systems and the theory of the singular traveling wave systems to the traveling wave solutions of the equation, it is shown that for different k, the equation may have infinitely many solitary wave solutions, periodic wave solutions, kink/antikink wave solutions, cusped solitary wave solutions, and breaking loop solutions. We discuss in a detail the cases of k=-2,-(1/2),(1/2),2, and parametric representations of all possible bounded traveling wave solutions are given in the different (c,g)-parameter regions.
Solitary pancreas retransplant: Study of 22 cases
Directory of Open Access Journals (Sweden)
Tércio Genzini
2006-03-01
Full Text Available Objective: To present our experience with pancreas retransplantin patients previously submitted to simultaneous pancreas-kidneytransplant, pancreas after kidney transplant and pancreastransplant alone. Methods: Between January/1996 and December/2005, 330 pancreas transplants were performed: 308 primarytransplants and 22 (6% retransplants of solitary pancreas. Thefollowing variables were analyzed: patient age; time elapsedbetween the first and the second transplant; causes of loss of thefirst graft; technical characteristics of the transplant andretransplant and the criteria for selecting donors for retransplant.These clinical data were submitted to statistical analysis. Results:The mean age of patients was 34.3 years and the mean elapsedtime between the first and second transplant was 19.3 months.The causes of the first graft loss were venous (8; 35% and arterial(5; 23% thrombosis, chronic rejection (4; 18%, ischemia/reperfusion injury (2, reflux pancreatitis (1, primary non-function(1 and sepsis (1. A second transplant was performed in thesame iliac fossa in 16 patients (72%. Venous drainage wasperformed in the iliac vein in 16 patients (72%, in the inferior venacava in 5 patients (22% and in the portal vein in one patient. 6 allbladder drainage was the technique used in 18 (82% cases andenteric drainage, in 4 patients (18%. Immunosuppressive regimenapplied to all cases was quadruple therapy with antilymphocyteinduction, tacrolimus, mycophenolate mofetil and steroids. Therewas one early death due to sepsis. One-year patient and pancreasgraft survival rates for retransplants were, respectively, 95% and85%. There was no additional risk for removing the pancreas graftat retransplant. Conclusion: Pancreas retransplant was technicallyfeasible in all cases and results similar to those described in theliterature were found for primary pancreas transplant.
Imaging features of intracranial solitary fibrous tumors
International Nuclear Information System (INIS)
Yu Shuilian; Man Yuping; Ma Longbai; Liu Ying; Wei Qiang; Zhu Youkai
2012-01-01
Objective: To summarize the imaging features of intracranial solitary fibrous tumors (ISFT). Methods: Ten patients with ISFT proven histopathologically were collected. Four cases had CT data and all cases had MR data. The imaging features and pathological results were retrospectively analyzed. Results: All cases were misdiagnosed as meningioma at pre-operation. All lesions arose from intracranial meninges including 5 lesions above the tentorium, 4 lesions beneath the tentorium and 1 lesion growing around the tentorium. The margins of all the masses were well defined, and 8 lesions presented multilobular shape. CT demonstrated hyerattenuated masses in all 4 lesions, smooth erosion of the basicranial skull in 1 lesion, and punctiform calcification of the capsule in 1 lesion. T 1 WI showed most lesions with isointense or slight hyperintense signals including homogeneous in 4 lesions and heterogeneous in 6 lesions. T 2 WI demonstrated isointense or slight hyperintense in 2 lesions, mixed hypointense and hyperintense signals in 4, cystic portion in 2, and two distinct portion of hyperintense and hypointense signal, so called 'yin-yang' pattern, in 2. Strong enhanced was found in all lesions, especially in 8 lesion with heterogeneous with the low T 2 signal. 'Dural tail' was found in 4 lesions. Conclusions: ISFI has some specific CT and MR features including heterogeneous signal intensity on T 2 WI, strong enhancement of areas with low T 2 signal intensity, slight or no 'dural tail', without skull thickening, and the typical 'yin-yang' pattern. (authors)