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Applications and Applied Mathematics: An International Journal (AAM)

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Articles 331 - 360 of 702

Full-Text Articles in Applied Mathematics

Conformable Derivative Operator In Modelling Neuronal Dynamics, Mehmet Yavuz, Burcu Yaşkıran Dec 2018

Conformable Derivative Operator In Modelling Neuronal Dynamics, Mehmet Yavuz, Burcu Yaşkıran

Applications and Applied Mathematics: An International Journal (AAM)

This study presents two new numerical techniques for solving time-fractional one-dimensional cable differential equation (FCE) modeling neuronal dynamics. We have introduced new formulations for the approximate-analytical solution of the FCE by using modified homotopy perturbation method defined with conformable operator (MHPMC) and reduced differential transform method defined with conformable operator (RDTMC), which are derived the solutions for linear-nonlinear fractional PDEs. In order to show the efficiencies of these methods, we have compared the numerical and exact solutions of fractional neuronal dynamics problem. Moreover, we have declared that the proposed models are very accurate and illustrative techniques in determining to approximate-analytical …

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Parameter Estimation And Optimal Control Of The Dynamics Of Transmission Of Tuberculosis With Application To Cameroon, A. Temgoua, Y. Malong, J. Mbang, S. Bowong Dec 2018

Parameter Estimation And Optimal Control Of The Dynamics Of Transmission Of Tuberculosis With Application To Cameroon, A. Temgoua, Y. Malong, J. Mbang, S. Bowong

Applications and Applied Mathematics: An International Journal (AAM)

This paper deals with the problem of parameter estimation and optimal control of a tuberculosis (TB) model with seasonal fluctuations. We first present a uncontrolled TB model with seasonal fluctuations. We present the theoretical analysis of the uncontrolled TB model without seasonal fluctuations. After, we propose a numerical study to estimate the unknown parameters of the TB model with seasonal fluctuations according to demographic and epidemiological data from Cameroon. Simulation results are in good accordance with the seasonal variation of the new active reported cases of TB in Cameroon. Using this TB model with seasonality, the tuberculosis control is formulated …

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Induced Hesitant 2-Tuple Linguistic Aggregation Operators With Application In Group Decision Making, Tabasam Rashid, Ismat Beg, Raja N. Jamil Dec 2018

Induced Hesitant 2-Tuple Linguistic Aggregation Operators With Application In Group Decision Making, Tabasam Rashid, Ismat Beg, Raja N. Jamil

Applications and Applied Mathematics: An International Journal (AAM)

In this article, hesitant 2-tuple linguistic arguments are used to evaluate the group decision making problems which have inter dependent or inter active attributes. Operational laws are developed for hesitant 2-tuple linguistic elements and based on these operational laws hesitant 2- tuple weighted averaging operator and generalized hesitant 2- tuple averaging operator are proposed. Combining Choquet integral with hesitant 2-tuple linguistic information, some new aggregation operators are defined, including the hesitant 2-tuple correlated averaging operator, the hesitant 2-tuple correlated geometric operator and the generalized hesitant 2-tuple correlated averaging operator. These proposed operators successfully manage the correlations among the elements. After …

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On Processability Of Lemke’S Algorithm, R. Jana, A. K. Das, S. Sinha Dec 2018

On Processability Of Lemke’S Algorithm, R. Jana, A. K. Das, S. Sinha

Applications and Applied Mathematics: An International Journal (AAM)

Lemke’s algorithm is a pivotal kind of algorithm which is developed based on principal pivot transform. We consider several matrix classes to study the relationship among them in the context of linear complementarity problem. These classes are important from Lemke’s algorithmic point of view. In this article we discuss about the processability of Lemke’s algorithm with respect to some selective matrix classes.

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Restricted Three-Body Problem Under The Effect Of Albedo When Smaller Primary Is A Finite Straight Segment, Shipra Chauhan, Dinesh Kumar, Bhavneet Kaur Dec 2018

Restricted Three-Body Problem Under The Effect Of Albedo When Smaller Primary Is A Finite Straight Segment, Shipra Chauhan, Dinesh Kumar, Bhavneet Kaur

Applications and Applied Mathematics: An International Journal (AAM)

This paper addresses the dynamics of the infinitesimal body in the restricted three-body problem under the effect of Albedo when the smaller primary is a finite straight segment and bigger one is a source of radiation. The measure of diffusive reflection of solar radiation out of the total solar radiation received by a body is Albedo which is measured on a scale from 0 to 1. The equations of motion of the infinitesimal body are derived and it is found that there exist five libration points, out of which three are collinear and the rest are non-collinear with the primaries. …

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An Interpolation Process On The Roots Of Ultraspherical Polynomials, R. Srivastava, Yamini Singh Dec 2018

An Interpolation Process On The Roots Of Ultraspherical Polynomials, R. Srivastava, Yamini Singh

Applications and Applied Mathematics: An International Journal (AAM)

The paper is devoted to studying a Pál-type interpolation problem on the roots of Ultraspherical polynomials of degree n-1 with parameter k+1 on the closed interval -1 to 1. The aim of this paper is to find a unique interpolatory polynomial of degree at most m equal to 2n+2k+1 satisfying the interpolatory conditions that is, function values of the polynomial of degree m at the zeros of the function values of the ultraspherical polynomials and the first derivative values of the polynomial of degree m at the zeros of the first derivative values of the ultraspherical polynomials.We will use the …

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Stability And Bifurcation Analysis Of A Delayed Three Species Food Chain Model With Crowley-Martin Response Function, Ashok Mondal, A. K. Pal, G. P. Samanta Dec 2018

Stability And Bifurcation Analysis Of A Delayed Three Species Food Chain Model With Crowley-Martin Response Function, Ashok Mondal, A. K. Pal, G. P. Samanta

Applications and Applied Mathematics: An International Journal (AAM)

In this paper we have studied the dynamical behaviors of three species prey-predator system. The interaction between prey and middle-predator is Crowley-Martin type functional response. Positivity and boundedness of the system are discussed. Stability analysis of the equilibrium points is presented. Permanence and Hopf-bifurcation of the system are analyzed under some conditions. The effect of discrete time-delay is studied, where the delay may be regarded as the gestation period of the super-predator. The direction and the stability criteria of the bifurcating periodic solutions are determined with the help of the normal form theory and the center manifold theorem. Extensive numerical …

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Inventory Model With Ramp-Type Demand And Price Discount On Back Order For Deteriorating Items Under Partial Backlogging, Sumit Saha, Nabendu Sen, Biman K. Nath Jun 2018

Inventory Model With Ramp-Type Demand And Price Discount On Back Order For Deteriorating Items Under Partial Backlogging, Sumit Saha, Nabendu Sen, Biman K. Nath

Applications and Applied Mathematics: An International Journal (AAM)

Modeling of inventory problems provides a good insight to retailers and distributors to maintain stock of different items such as seasonal products, perishable goods and daily useable goods etc. The deterioration of all these items exists to a certain extent due to several reasons like mishandling, evaporation, decay, environmental conditions, transportation etc. It is found from the literature that previously many of the researchers have developed inventory model ignoring deterioration and drawn conclusion. In the absence of deterioration parameter, an inventory model cannot be completely realistic. In this paper, we have made an attempt to extend an inventory model with …

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An Accelerate Process For The Successive Approximations Method In The Case Of Monotonous Convergence, A. Laouar, I. Mous Jun 2018

An Accelerate Process For The Successive Approximations Method In The Case Of Monotonous Convergence, A. Laouar, I. Mous

Applications and Applied Mathematics: An International Journal (AAM)

We study an iterative process to accelerate the successive approximations method in a monotonous convergence framework. It consists in interrupting the sequence of the successive approximations method produced at the kth iteration and substituting it by a combination of the element of the sequence produced at the iterate k + 1 and an extrapolation vector. The latter uses a parameter which can be calculated mathematically. We illustrate numerically this process by studying a freeboundary problems class.

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Solution For System Of Fractional Partial Differential Equations, D. B. Dhaigude, Swati N. Kanade, C. D. Dhaigude Jun 2018

Solution For System Of Fractional Partial Differential Equations, D. B. Dhaigude, Swati N. Kanade, C. D. Dhaigude

Applications and Applied Mathematics: An International Journal (AAM)

The purpose of this article is to discuss solutions of different initial value problems (IVPs) for system of fractional differential equations. These equations appear in physical processes such as transportation and anomalous diffusion. The iteration method is successfully developed and series solution of IVPs at hand are obtained which converges to a function known as solution function of the IVPs. Graphical representation of solution of some IVPs are given using Mathematical software “MATLAB”.

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Method Of Deriving Companion Identities Associating Q-Series, Keshav P. Yadav, Adarsh Kumar Jun 2018

Method Of Deriving Companion Identities Associating Q-Series, Keshav P. Yadav, Adarsh Kumar

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we have established two theorems by making use of Euler’s q-derivative and qshifted operators for a function of one variable and also for function of two variables. We derived several companion identities by applying these theorems on some known q-series identities. We deduced several special cases which are also the companion identities in the last section of the paper.

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A Mathematical Study For The Existence And Survival Of Human Population In A Polluted Environment, Manju Agarwal, Preeti _ Jun 2018

A Mathematical Study For The Existence And Survival Of Human Population In A Polluted Environment, Manju Agarwal, Preeti _

Applications and Applied Mathematics: An International Journal (AAM)

Rapidly rising population and increasing urbanization have the potential for producing a high level of pollution. Pollutants have the ability to change the distributions of patterns of plants and animals. Some of the main pollutant categories are water pollutants, air pollution, pesticides, and radioactive waste. Most abundantly toxicants are produced by the chemical and medical industries. We used food crops that are produced by using pesticide and herbicides, etc. Due to the enormous variety of toxic substances are present in the atmosphere, it is challenging task to determine the potential ecological and human health risk. Keeping all these things in …

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On Indexed Absolute Matrix Summability Of An Infinite Series, Lakshmi N. Mishra, P. K. Das, P. Samanta, M. Misra, U. K. Misra Jun 2018

On Indexed Absolute Matrix Summability Of An Infinite Series, Lakshmi N. Mishra, P. K. Das, P. Samanta, M. Misra, U. K. Misra

Applications and Applied Mathematics: An International Journal (AAM)

Some results have been established on absolute index Riesz summability factor of an infinite series. Furthermore, these kind of results can be extended by taking other parameters and an absolute index matrix summability factor of an infinite series or some weaker conditions. In the present paper a new result on generalized absolute index matrix summability factor of an infinite series has been established.

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A Numerical Method For Functional Hammerstein Integro-Differential Equations, L. Saeedi, A. Tari Jun 2018

A Numerical Method For Functional Hammerstein Integro-Differential Equations, L. Saeedi, A. Tari

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, a numerical method is presented to solve functional Hammerstein integro-differential equations. The presented method combines the successive approximations method with trapezoidal quadrature rule and natural cubic spline interpolation to solve the mentioned equations. The existence and uniqueness of the problem is also investigated. The convergence and numerical stability of the problem are proved, and finally, the accuracy of the method is verified by presenting some numerical computations.

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System Reliability Using Generalized Intuitionistic Fuzzy Rayleigh Lifetime Distribution, Ali Ebrahimnejad, Ezzatallah B. Jamkhaneh Jun 2018

System Reliability Using Generalized Intuitionistic Fuzzy Rayleigh Lifetime Distribution, Ali Ebrahimnejad, Ezzatallah B. Jamkhaneh

Applications and Applied Mathematics: An International Journal (AAM)

Reliability analysis as one of the important research topics in engineering has been researched by a number of authors. Reliability in classical distributions is based on precise parameters. It is usually assumed that parameters of distributions are precise real numbers. However, in the real world, the data sometimes cannot be measured and recorded precisely. In this paper, the concept of fuzzy reliability is extended by the idea of generalized intuitionistic fuzzy reliability. We investigate the reliability characteristics of systems using Rayleigh lifetime distribution, in which the lifetime parameter is assumed to be generalized intuitionistic fuzzy number. Generalized intuitionistic fuzzy reliability, …

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Generalized Problem Of Thermal Bending Analysis In The Cartesian Domain, V. S. Kulkarni, Vinayaki Parab Jun 2018

Generalized Problem Of Thermal Bending Analysis In The Cartesian Domain, V. S. Kulkarni, Vinayaki Parab

Applications and Applied Mathematics: An International Journal (AAM)

This is an attempt for mathematical formulation and general analytical solution of the most generalized thermal bending problem in the Cartesian domain. The problem has been formulated in the context of non-homogeneous transient heat equation subjected to Robin’s boundary conditions. The general solution of the generalized thermoelastic problem has been discussed for temperature change, displacements, thermal stresses, deflection, and deformation. The most important feature of this work is any special case of practical interest may be readily obtained by this most generalized mathematical formulation and its analytical solution. There are 729 such combinations of possible boundary conditions prescribed on parallelepiped …

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Global Stability Of Ebola Virus Disease Model With Contact Tracing And Quarantine, Chinwendu E. Madubueze, Anande R. Kimbir, Terhemen Aboiyar Jun 2018

Global Stability Of Ebola Virus Disease Model With Contact Tracing And Quarantine, Chinwendu E. Madubueze, Anande R. Kimbir, Terhemen Aboiyar

Applications and Applied Mathematics: An International Journal (AAM)

This study considers a deterministic model of Ebola Virus Disease (EVD) incorporating contact tracing and quarantine as interventions. The model analyze the existence and stability of Disease-Free Equilibrium (DFE) and Endemic Equilibrium (EE) states. The local stability of EE is established using centre manifold theorem. The global stability of the two equilibrium states are obtained by constructing the Lyapunov function. Numerical simulations are carried out to examine the impact of contact tracing and quarantine measures on the transmission dynamics of EVD. The result indicates that EVD could be eliminated faster when contact tracing and quarantine measures are implemented together.

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Ultimate Boundedness And Periodicity Results For A Certain System Of Third-Order Nonlinear Vector Delay Differential Equations, Linda D. Oudjedi, Moussadek Remili Jun 2018

Ultimate Boundedness And Periodicity Results For A Certain System Of Third-Order Nonlinear Vector Delay Differential Equations, Linda D. Oudjedi, Moussadek Remili

Applications and Applied Mathematics: An International Journal (AAM)

In the last years, there has been increasing interest in obtaining the sufficient conditions for stability, instability, boundedness, ultimately boundedness, convergence, etc. For instance, in applied sciences some practical problems concerning mechanics, engineering technique fields, economy, control theory, physical sciences and so on are associated with third, fourth and higher order nonlinear differential equations. The problem of the boundedness and stability of solutions of vector differential equations has been widely studied by many authors, who have provided many techniques especially for delay differential equations. In this work a class of third order nonlinear non-autonomous vector delay differential equations is considered …

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Flow Maximization Problem As Linear Programming Problem With Capacity Constraints, Sushil C. Dimri, Mangey Ram Jun 2018

Flow Maximization Problem As Linear Programming Problem With Capacity Constraints, Sushil C. Dimri, Mangey Ram

Applications and Applied Mathematics: An International Journal (AAM)

Flow maximization is a fundamental problem in mathematics; there are several algorithms available to solve this problem, but these algorithms have some limitations. This paper presents the flow maximization problem as a Linear Programming Problem (L.P.P.). The solution given by L.P.P. formulation of the problem and provided by Ford Fulkerson algorithm is same. This paper also compares the single path flow and k-splitting of the flow and suggests that k-splitting of flow is better than single path flow.

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A New Approach To Solve Multi-Objective Transportation Problem, Lakhveer Kaur, Madhuchanda \ Rakshit, Sandeep Singh Jun 2018

A New Approach To Solve Multi-Objective Transportation Problem, Lakhveer Kaur, Madhuchanda \ Rakshit, Sandeep Singh

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, a simple approach is proposed to obtain the best compromise solution of linear multiobjective transportation problem (MOTP). Using this approach, we get unique efficient solution. Because unique efficient extreme point obtained by proposed approach directly leads to compromise solution, which is preferred by decision maker. Also this approach is simple to use and less time consuming. For the application of proposed approach, numerical examples are considered from existing literature and are solved with proposed method.

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Estimation Of The Burr Xii-Exponential Distribution Parameters, Gholamhossein Yari, Zahra Tondpour Jun 2018

Estimation Of The Burr Xii-Exponential Distribution Parameters, Gholamhossein Yari, Zahra Tondpour

Applications and Applied Mathematics: An International Journal (AAM)

The Burr XII distribution is one of the most important distributions in Survival analysis. In this article, we introduce the new wider Burr XII-G family of distributions. A special model in the new family called Burr XII-exponential distribution that has constant, decreasing and unimodal hazard rate functions is investigated. We discuss the estimation of this distribution parameters by maximum likelihood, three modifications of maximum likelihood and Bayes methods. In Bayes method, we use the uniform, triangular and Burr XII-uniform priors for posterior analysis and obtain Bayes estimations under two different loss functions. We obtain two approximations of the Bayes estimations, …

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Resonance In The Motion Of A Geocentric Satellite Due To Poynting-Robertson Drag, Charanpreet Kaur, Binay K. Sharma, L. P. Pandey Jun 2018

Resonance In The Motion Of A Geocentric Satellite Due To Poynting-Robertson Drag, Charanpreet Kaur, Binay K. Sharma, L. P. Pandey

Applications and Applied Mathematics: An International Journal (AAM)

The problem of resonance in a geocentric Satellite under the combined gravitational forces of the Sun and the Earth due to Poynting-Robertson (P-R) drag has been discussed in this paper with the assumption that all three bodies, the Earth, the Sun and the Satellite, lie in an ecliptic plane. Our approach differs from conventional ones as we have placed evaluated velocity of the Satellite in equations of motion.We observed five resonance points commensurable between the mean motion of the Satellite and the average angular velocity of the Earth around the Sun, out of which two resonances occur only due to …

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Finite Element Solution Of The Two-Dimensional Incompressible Navier-Stokes Equations Using Matlab, Endalew G. Tsega, V. K. Katiyar Jun 2018

Finite Element Solution Of The Two-Dimensional Incompressible Navier-Stokes Equations Using Matlab, Endalew G. Tsega, V. K. Katiyar

Applications and Applied Mathematics: An International Journal (AAM)

The Navier–Stokes equations are fundamental in fluid mechanics. The finite element method has become a popular method for the solution of the Navier-Stokes equations. In this paper, the Galerkin finite element method was used to solve the Navier-Stokes equations for two-dimensional steady flow of Newtonian and incompressible fluid with no body forces using MATLAB. The method was applied to the lid-driven cavity problem. The eight-noded rectangular element was used for the formulation of element equations. The velocity components were located at all of 8 nodes and the pressure variable is located at 4 corner of the element. From location of …

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Profit Analysis Of A Two Unit Cold Standby System Operating Under Different Weather Conditions Subject T O Inspection, M. S. Barak, Neeraj _, Sudesh Kumari Jun 2018

Profit Analysis Of A Two Unit Cold Standby System Operating Under Different Weather Conditions Subject T O Inspection, M. S. Barak, Neeraj _, Sudesh Kumari

Applications and Applied Mathematics: An International Journal (AAM)

A system, or unit, is said to be working under normal weather conditions if the system is working under prescribed conditions as defined/stated by the definition of reliability of system/unit, otherwise the system is said to be working in abnormal weather conditions. For example, if a car with the capacity for five persons is carrying more than five persons, it will be said to be working under abnormal weather conditions. Another example, if a hydraulic machine having the capacity to lift a maximum weight of 500 tons is lifting a weight of 600 tons, then the machine is working under …

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Evaluation Of Some Reliability Characteristics Of A Single Unit System Requiring Two Types Of Supporting Device For Operations, Ibrahim Yusuf, Nura J. Fagge Dec 2017

Evaluation Of Some Reliability Characteristics Of A Single Unit System Requiring Two Types Of Supporting Device For Operations, Ibrahim Yusuf, Nura J. Fagge

Applications and Applied Mathematics: An International Journal (AAM)

This study presents the reliability assessment of a single unit connected to two types of external supporting devices for its operation. Each type of external supporting device has two copies I and II on standby. First order differential difference equations method is used to obtain the explicit expression for the steady state availability, busy period due to failure of type I and II supporting devices of repairmen, steady-state availability and profit function. Based on assumed numerical values given to system parameters, graphical illustrations are given to highlight important results. Comparisons are performed to highlight the impact of unit failure and …

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On The Qualitative Behaviors Of A Functional Differential Equation Of Second Order, Cemil Tunç Dec 2017

On The Qualitative Behaviors Of A Functional Differential Equation Of Second Order, Cemil Tunç

Applications and Applied Mathematics: An International Journal (AAM)

The aim of this paper is first to investigate the stability of the zero solution to a new Liénard type equation with multiple variable delays by two different methods. The methods to be used in the proofs involve the Lyapunov-Krasovskiĭ functional approach and the fixed point technique under an exponentially weighted metric, respectively. We make a comparison between the applications of these methods with the established conditions on the same stability problems. Then, we obtain three new results for uniformly stability and boundedness/ uniformly boundedness of the solutions to the considered equation by the Lyapunov-Krasovskiĭ functional approach. An example is …

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On The Lp-Spaces Techniques In The Existence And Uniqueness Of The Fuzzy Fractional Korteweg-De Vries Equation’S Solution, F. Farahrooz, A. Ebadian, S. Najafzadeh Dec 2017

On The Lp-Spaces Techniques In The Existence And Uniqueness Of The Fuzzy Fractional Korteweg-De Vries Equation’S Solution, F. Farahrooz, A. Ebadian, S. Najafzadeh

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, is proposed the existence and uniqueness of the solution of all fuzzy fractional differential equations, which are equivalent to the fuzzy integral equation. The techniques on LP-spaces are used, defining the LpF F ([0; 1]) for 1≤P≤∞, its properties, and using the functional analysis methods. Also the convergence of the method of successive approximations used to approximate the solution of fuzzy integral equation be proved and an iterative procedure to solve such equations is presented.

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Interactions Of Thermoelastic Beam In Modified Couple Stress Theory, Rajneesh Kumar, Shaloo Devi Dec 2017

Interactions Of Thermoelastic Beam In Modified Couple Stress Theory, Rajneesh Kumar, Shaloo Devi

Applications and Applied Mathematics: An International Journal (AAM)

This paper is concerned with the study of thermoelastic beam in modified couple stress theory. The governing equations of motion for modified couple stress theory and heat conduction equation for non-Fourier (non-classical process) are investigated to model the vibrations in a homogeneous isotropic thin beam in a closed form by employing the Euler Bernoulli beam theory. The generalized theories of thermoelasticity with one and two relaxation times are used to model the problem. Both ends of the beam are simply supported. The Laplace transform technique applied to solve the system of equations which are written in dimensionless form. A general …

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Numerical Experiments For Finding Roots Of The Polynomials In Chebyshev Basis, M. S. Solary Dec 2017

Numerical Experiments For Finding Roots Of The Polynomials In Chebyshev Basis, M. S. Solary

Applications and Applied Mathematics: An International Journal (AAM)

Root finding for a function or a polynomial that is smooth on the interval [a; b], but otherwise arbitrary, is done by the following procedure. First, approximate it by a Chebyshev polynomial series. Second, find the zeros of the truncated Chebyshev series. Finding roots of the Chebyshev polynomial is done by eigenvalues of a nXn matrix such as companion or comrade matrices. There are some methods for finding eigenvalues of these matrices such as companion matrix and chasing procedures.We derive another algorithm by second kind of Chebyshev polynomials.We computed the numerical results of these methods for some special and ill-conditioned …

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Analytical Solution For Determination The Control Parameter In The Inverse Parabolic Equation Using Ham, M. M. Khader Dec 2017

Analytical Solution For Determination The Control Parameter In The Inverse Parabolic Equation Using Ham, M. M. Khader

Applications and Applied Mathematics: An International Journal (AAM)

In this article, the homotopy analysis method (HAM) for obtaining the analytical solution of the inverse parabolic problem and computing the unknown time-dependent parameter is introduced. The series solution is developed and the recurrence relations are given explicitly. Special attention is given to satisfy the convergence of the proposed method. A comparison of HAM with the variational iteration method is made. In the HAM, we use the auxiliary parameter ~ to control with a simple way in the convergence region of the solution series. Applying this method with several

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