The Generalised Zakharov-Shabat System And The Gauge Group Action,
2012
Technological University Dublin
The Generalised Zakharov-Shabat System And The Gauge Group Action, Georgi Grahovski
Articles
The generalized Zakharov-Shabat systems with complex-valued non-regular Cartan elements and the systems studied by Caudrey, Beals and Coifman (CBC systems) and their gauge equivalent are studied. This study includes: the properties of fundamental analytical solutions (FAS) for the gauge-equivalent to CBC systems and the minimal set of scattering data; the description of the class of nonlinear evolutionary equations, solvable by the inverse scattering method, and the recursion operator, related to such systems; the hierarchies of Hamiltonian structures. The results are illustrated on the example of the multi-component nonlinear Schrodinger (MNLS) equations and the corresponding gauge-equivalent multi-component Heisenberg ferromagnetic (MHF) type …
Modelling Β2ar Regulation,
2011
The University of Texas Graudate School of Biomedical Sciences at Houston
Modelling Β2ar Regulation, Sharat J. Vayttaden
Dissertations and Theses (Open Access)
The β2 adrenergic receptor (β2AR) regulates smooth muscle relaxation in the vasculature and airways. Long- and Short-acting β-agonists (LABAs/SABAs) are widely used in treatment of chronic obstructive pulmonary disorder (COPD) and asthma. Despite their widespread clinical use we do not understand well the dominant β2AR regulatory pathways that are stimulated during therapy and bring about tachyphylaxis, which is the loss of drug effects. Thus, an understanding of how the β2AR responds to various β-agonists is crucial to their rational use. Towards that end we have developed deterministic models that explore the mechanism of drug- induced β2AR regulation. These mathematical models …
A New Hermite Collocation Method For Solving Differential Difference Equations,
2011
Mugla University
A New Hermite Collocation Method For Solving Differential Difference Equations, Mustafa Gülsu, Hatice Yalman, Mehmet Sezer
Applications and Applied Mathematics: An International Journal (AAM)
The purpose of this study is to give a Hermite polynomial approximation for the solution of mth order linear differential-difference equations with variable coefficients under mixed conditions. For this purpose, a new Hermite collocation method is introduced. This method is based on the truncated Hermite expansion of the function in the differential-difference equations. Hence, the resulting matrix equation can be solved and the unknown Hermite coefficients can be found approximately. In addition, examples that illustrate the pertinent features of the method are presented and the results of the study discussed
Solitary, Explosive, Rational And Elliptic Doubly Periodic Solutions For Nonlinear Electron-Acoustic Waves In The Earth’S Magnetotail Region With Cold Electron Fluid And Isothermal Ions,
2011
Mansoura University
Solitary, Explosive, Rational And Elliptic Doubly Periodic Solutions For Nonlinear Electron-Acoustic Waves In The Earth’S Magnetotail Region With Cold Electron Fluid And Isothermal Ions, S. A. El-Wakil, E. M. Abulwafa, M. A. Abdou, E. K. El-Shewy, H. M. Abd-El-Hamid
Applications and Applied Mathematics: An International Journal (AAM)
A theoretical investigation has been made of electron acoustic wave propagating in unmagnetized collisionless plasma consisting of a cold electron fluid and isothermal ions with two different temperatures obeying Boltzmann type distributions. Based on the pseudo-potential approach, large amplitude potential structures and the existence of Solitary waves are discussed. The reductive perturbation method has been employed to derive the Korteweg-de Vries equation for small but finite amplitude electrostatic waves. 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 KdV equation, is …
Dust-Acoustic Solitary Waves In Magnetized Dusty Plasma With Dust Opposite Polarity,
2011
Mansoura University
Dust-Acoustic Solitary Waves In Magnetized Dusty Plasma With Dust Opposite Polarity, S. A. El-Wakil, M. T. Attia, E. K. El-Shewy, S. K. Zaghbeer, H. G. Abdelwahed
Applications and Applied Mathematics: An International Journal (AAM)
The nonlinear propagation of small but finite amplitude dust-acoustic solitary waves (DAWs) in magnetized collision less dusty plasma has been investigated. The fluid model is a four component magnetized dusty plasma, consisting of positive and negative dust species, isothermal electrons and ions in the presence of an external magnetic field. A reductive perturbation method was employed to obtain the Zakharov Kuznetsov (ZK) equation for the first-order potential. The effects of the presence of positively charged dust fluid, the external magnetic field, and the obliqueness are obtained. The results of the present investigation may be applicable to some plasma environments, such …
Positive Solutions For Nth Order Differential Equations Under Some Conditions,
2011
Qassim University
Positive Solutions For Nth Order Differential Equations Under Some Conditions, S. N. Odda
Applications and Applied Mathematics: An International Journal (AAM)
This paper presents an existence and nonexistence of positive solutions for the nonlinear boundary value problems. We prove that the nth order nonlinear differential equation has at least one positive solution by using appropriate fixed point theorems.
Exact Soliton Solutions For Second-Order Benjamin-Ono Equation,
2011
University of Guilan
Exact Soliton Solutions For Second-Order Benjamin-Ono Equation, Nasir Taghizadeh, Mohammad Mirzazadeh, Foroozan Farahrooz
Applications and Applied Mathematics: An International Journal (AAM)
The homogeneous balance method is proposed for seeking the travelling wave solutions of the second-order Benjamin-Ono equation. Many exact traveling wave solutions of second-order Benjamin-Ono equation, which contain soliton like and periodic-like solutions are successfully obtained. This method is straightforward and concise, and it may also be applied to other nonlinear evolution equations.
Inverse Heat Conduction Problem In A Semi-Infinite Cylinder And Its Thermal Stresses By Quasi-Static Approach,
2011
Nagpur University
Inverse Heat Conduction Problem In A Semi-Infinite Cylinder And Its Thermal Stresses By Quasi-Static Approach, K. C. Deshmukh, S. D. Warbhe, G. D. Kedar, V. S. Kulkarni
Applications and Applied Mathematics: An International Journal (AAM)
The present paper deals with the determination of unknown temperature and thermal stresses on the curved surface of a semi-infinite circular cylinder defined as 0 ≤ r ≤ a , 0 ≤ z ≤ ∞. The circular cylinder is subjected to an arbitrary known temperature under unsteady state condition. Initially, the cylinder is at zero temperature and temperature at the lower surface is held fixed at zero. The governing heat conduction equation has been solved by using the integral transform method. The results are obtained in series form in terms of Bessel’s functions. A mathematical model has been constructed for …
Algorithms To Solve Singularly Perturbed Volterra Integral Equations,
2011
Jordan University of Science and Technology
Algorithms To Solve Singularly Perturbed Volterra Integral Equations, Marwan T. Alquran, Bilal Khair
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, we apply the Differential Transform Method (DTM) and Variational Iterative Method (VIM) to develop algorithms for solving singularly perturbed volterra integral equations (SPVIEs). The study outlines the significant features of the two methods. A comparison between the two methods for the solution of SPVIs is given for three examples. The results show that both methods are very efficient, convenient and applicable to a large class of problems.
Analytic And Numerical Studies Of A Simple Model Of Attractive-Repulsive Swarms,
2011
Harvey Mudd College
Analytic And Numerical Studies Of A Simple Model Of Attractive-Repulsive Swarms, Andrew S. Ronan
HMC Senior Theses
We study the equilibrium solutions of an integrodifferential equation used to model one-dimensional biological swarms. We assume that the motion of the swarm is governed by pairwise interactions, or a convolution in the continuous setting, and derive a continuous model from conservation laws. The steady-state solution found for the model is compactly supported and is shown to be an attractive equilibrium solution via linear perturbation theory. Numerical simulations support that the steady-state solution is attractive for all initial swarm distributions. Some initial results for the model in higher dimensions are also presented.
Mathematical Analysis And Applications Of Logistic Differential Equation,
2011
University of Nevada, Las Vegas
Mathematical Analysis And Applications Of Logistic Differential Equation, Eva Arnold, Monika Neda
Festival of Communities: UG Symposium (Posters)
Logistic differential equation has a way to measure the proportionality of various resources with respect to time. This equation has been used in many research areas, such as, biology, medicine, psychology, economics, etc. A mathematical description, analysis and solution of the logistic type differential equation is studied. Besides the mathematical part, the poster will contain biological examples, graphs of the direction fields for different parameter settings and logistic plots for specific species population. The logistic growth function will also be applied to learning curves in area of psychology, as a rate at which performance improves.
Neural Spike Renormalization. Part I — Universal Number 1,
2011
University of Nebraska-Lincoln
Neural Spike Renormalization. Part I — Universal Number 1, Bo Deng
Department of Mathematics: Faculty Publications
For a class of circuit models for neurons, it has been shown that the transmembrane electrical potentials in spike bursts have an inverse correlation with the intra-cellular energy conversion: the fewer spikes per burst the more energetic each spike is. Here we demonstrate that as the per-spike energy goes down to zero, a universal constant to the bifurcation of spike-bursts emerges in a similar way as Feigenbaum’s constant does to the period-doubling bifurcation to chaos generation, and the new universal constant is the first natural number 1.
Neural Spike Renormalization. Part Ii — Multiversal Chaos,
2011
University of Nebraska - Lincoln
Neural Spike Renormalization. Part Ii — Multiversal Chaos, Bo Deng
Department of Mathematics: Faculty Publications
Reported here for the first time is a chaotic infinite-dimensional system which contains infinitely many copies of every deterministic and stochastic dynamical system of all finite dimensions. The system is the renormalizing operator of spike maps that was used in a previous paper to show that the first natural number 1 is a universal constant in the generation of metastable and plastic spike-bursts of a class of circuit models of neurons.
Solutions Of Nonlinear Second Order Multi-Point Boundary Value Problems By Homotopy Perturbation Method,
2010
Banaras Hindu University
Solutions Of Nonlinear Second Order Multi-Point Boundary Value Problems By Homotopy Perturbation Method, S. Das, Sunil Kumar, O. P. Singh
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, we present an algorithm for the numerical solution of the second order multi- point boundary value problem with suitable multi boundary conditions. The algorithm is based on the homotopy perturbation approach and the solutions are calculated in the form of a rapid convergent series. It is observed that the method gives more realistic series solutions that converge very rapidly in physical problems. Illustrative numerical examples are provided to demonstrate the efficiency and simplicity of the proposed method in solving this type of multipoint boundary value problems.
On The Eigenvalue And Inertia Problems For Descriptor Systems,
2010
University of Guilan
On The Eigenvalue And Inertia Problems For Descriptor Systems, Asadollah Aasaraai, Kameleh N. Pirbazari
Applications and Applied Mathematics: An International Journal (AAM)
The present study is intended to demonstrate that for a descriptor system with matrix pencil there exists a matrix such that matrix and matrix pencil have the same positive and negative eigenvalues. It is also shown that matrix can be calculated as a contour integral. On the other hand, different representations for matrix are introduced.
Global Stability Of Worms In Computer Network,
2010
Birla Institute of Technology
Global Stability Of Worms In Computer Network, Bimal Kumar Mishra, Aditya Kumar Singh
Applications and Applied Mathematics: An International Journal (AAM)
An attempt has been made to show the impact of non-linearity of the worms through SIRS (susceptible – infectious – recovered - susceptible) and SEIRS (susceptible – exposed – infectious – recovered - susceptible) e-epidemic models in computer network. A very general form of non-linear incidence rate has been considered satisfying the worm propagating behavior in computer network. The concavity conditions with a non-linear incidence rate and under the constant population size assumption are shown to be stable. Such systems have either a unique and stable endemic equilibrium state or no endemic equilibrium state at all; in the latter case, …
Approximate Approach To The Das Model Of Fractional Logistic Population Growth,
2010
Banaras Hindu University
Approximate Approach To The Das Model Of Fractional Logistic Population Growth, S. Das, P. K. Gupta, K. Vishal
Applications and Applied Mathematics: An International Journal (AAM)
In this article, the analytical method, Homotopy perturbation method (HPM) has been successfully implemented for solving nonlinear logistic model of fractional order. The fractional derivatives are described in the Caputo sense. Using initial value, the explicit solutions of population size for different particular cases have been derived. Numerical results show that the method is extremely efficient to solve this complicated biological model.
Analytic Treatment Of Vortex States In Cylindrical Superconductors In Applied Axial Magnetic Field,
2010
Embry-Riddle Aeronautical University
Analytic Treatment Of Vortex States In Cylindrical Superconductors In Applied Axial Magnetic Field, Andrei Ludu, J. Van Deun, M. V, Milosevic, A. Cuyt, F. M. Peeters
Publications
We solve the linear Ginzburg–Landau GL equation in the presence of a uniform magnetic field with cylindrical symmetry and we find analytic expressions for the eigenfunctions in terms of the confluent hypergeometric functions. The discrete spectrum results from an implicit equation associated to the boundary conditions and it is resolved in analytic form using the continued fractions formalism. We study the dependence of the spectrum and the eigenfunctions on the sample size and the surface conditions for solid and hollow cylindrical superconductors. Finally, the solutions of the nonlinear GL formalism are constructed as expansions in the linear GL eigenfunction basis …
Multistage Homotopy Analysis Method For Solving Nonlinear Integral Equations,
2010
University of Mazandaran
Multistage Homotopy Analysis Method For Solving Nonlinear Integral Equations, H. Jafari, M. A. Firoozjaee
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, we present an efficient modification of the homotopy analysis method (HAM) that will facilitate the calculations. We then conduct a comparative study between the new modification and the homotopy analysis method. This modification of the homotopy analysis method is applied to nonlinear integral equations and mixed Volterra-Fredholm integral equations, which yields a series solution with accelerated convergence. Numerical illustrations are investigated to show the features of the technique. The modified method accelerates the rapid convergence of the series solution and reduces the size of work.
An Approximate Analytical Solution Of The Fractional Diffusion Equation With External Force And Different Type Of Absorbent Term - Revisited,
2010
Banaras Hindu University
An Approximate Analytical Solution Of The Fractional Diffusion Equation With External Force And Different Type Of Absorbent Term - Revisited, S. Das, R. Kumar, P. K. Gupta
Applications and Applied Mathematics: An International Journal (AAM)
In this article Homotopy Perturbation Method (HPM) is applied to obtain an approximate analytical solution of a fractional diffusion equation with an external force and a reaction term different from the reaction term used by Das and Gupta (2010). The anomalous behavior of diffusivity in presence or absence of linear external force due to the presence of this force of reaction term are obtained and presented graphically.
