Shahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521Numerical method for solving a class of two-dimensional fractional optimal control problem of via operational matrices of Legendre polynomialNumerical method for solving a class of two-dimensional fractional optimal control problem of via operational matrices of Legendre polynomial1181527710.22055/jamm.2020.24146.1516FAYaserNouralizadeDepartment of Mathematics, Babol Noshirvani university of tecgnology, Babol, IranMahmoudBehroozifarDepartment of Mathematics, Babol Noshirvani university of tecgnology, Babol, IranMohsenAlipourDepartment of Mathematics, Babol Noshirvani university of tecgnology, Babol, IranJournal Article20171119 In this article, we present a numerical method for solving a class of two-dimensional fractional optimal control problems by the Legendre polynomial basis with fractional operational matrix. It should be mentioned that the dynamic system of the problem is based on the Caputo fractional partial derivative. This method, the dual integral is approximated by Gauss-Legendre rule, and then by using the Lagrangian equation, a nonlinear equation is obtained. This nonlinear equation set is solved by Newton's iterative method and unknown coefficients is determined. Finally, the proposed method was applied on a fractional problem with the different degree of fractional derivative. Also, the CPU time of method is exhibited. It is notable that all calculations were obtained by the Mathematica software. In this article, we present a numerical method for solving a class of two-dimensional fractional optimal control problems by the Legendre polynomial basis with fractional operational matrix. It should be mentioned that the dynamic system of the problem is based on the Caputo fractional partial derivative. This method, the dual integral is approximated by Gauss-Legendre rule, and then by using the Lagrangian equation, a nonlinear equation is obtained. This nonlinear equation set is solved by Newton's iterative method and unknown coefficients is determined. Finally, the proposed method was applied on a fractional problem with the different degree of fractional derivative. Also, the CPU time of method is exhibited. It is notable that all calculations were obtained by the Mathematica software.https://jamm.scu.ac.ir/article_15277_d4f8d53583a73342f0fdd4301316789f.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521A Nonlinear Control Scheme for Stabilization of Fractional Order Dynamical Chaotic SystemsA Nonlinear Control Scheme for Stabilization of Fractional Order Dynamical Chaotic Systems19381527810.22055/jamm.2020.26836.1622FAAhmadHaghighiFaculty of Basic Sciences, Technical and Vocational University (TVU), Tehran, IranMP. AghababaFaculty of Electrical and Computer Engineering, Urmia University of Technology, Urmia, IranNasimAsgharyFaculty of Basic Sciences, Islamic Azad University, Central Tehran Branch, Tehran, IranMajidRoohiSchool of Economics and Statistics, Guangzhou University, Guangzhou 510006, ChinaJournal Article20180823In this paper a nonlinear control method is designed to stabilize the fractional-order nonlinear chaotic systems (FONCS). The main feature of this control technique is swift convergence to the equilibrium point. Moreover, fractional version of Lyapunov stability theorem is utilized to prove the analytical results. Also, the ability of stabilization and robustness against system uncertainties are other characteristics of the proposed method. Numerical simulations are presented to emphasize the usefulness of the suggested approach in practice. It is worth to mention that the introduced nonlinear method can be used to control of almost all kind of uncertain chaotic fractional-order systems.In this paper a nonlinear control method is designed to stabilize the fractional-order nonlinear chaotic systems (FONCS). The main feature of this control technique is swift convergence to the equilibrium point. Moreover, fractional version of Lyapunov stability theorem is utilized to prove the analytical results. Also, the ability of stabilization and robustness against system uncertainties are other characteristics of the proposed method. Numerical simulations are presented to emphasize the usefulness of the suggested approach in practice. It is worth to mention that the introduced nonlinear method can be used to control of almost all kind of uncertain chaotic fractional-order systems.https://jamm.scu.ac.ir/article_15278_7dac91bb11b2a905a3f99c4800b0ed96.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521Modeling of Spatio-Temporal Data with Non-Ignorable MissingModeling of Spatio-Temporal Data with Non-Ignorable Missing39611527910.22055/jamm.2020.28698.1692FAMohsenMohammadzadehDepartment of Statistics, Tarbiat Modares University0000-0002-2361-6145SamiraZahmatkeshDepartment of Statistics, Tarbiat Modares UniversityJournal Article20190222Often, due to conditions under which measurements are made, spatio-temporal data contain missing values. Missing data in spatial or temporal vicinity may include useful information. Using this information, we can provide more accurate results, so missing data should be carefully examined. By modeling the missing process and spatio-temporal measurement process jointly, some lost information could be recovered. In this paper, we implement joint modeling in a Bayesian framework using the "shared parameter model" technique, so that the bad effects of missing values will be moderated. Also, we will associate these two processes via a latent spatio-temporal random field. To estimate the model parameters and for predictions, the Bayesian method INLA using SPDE approach is applied. Also, the lake surface water temperature data for Caspian sea is used to evaluate the performance of the joint model.Often, due to conditions under which measurements are made, spatio-temporal data contain missing values. Missing data in spatial or temporal vicinity may include useful information. Using this information, we can provide more accurate results, so missing data should be carefully examined. By modeling the missing process and spatio-temporal measurement process jointly, some lost information could be recovered. In this paper, we implement joint modeling in a Bayesian framework using the "shared parameter model" technique, so that the bad effects of missing values will be moderated. Also, we will associate these two processes via a latent spatio-temporal random field. To estimate the model parameters and for predictions, the Bayesian method INLA using SPDE approach is applied. Also, the lake surface water temperature data for Caspian sea is used to evaluate the performance of the joint model.https://jamm.scu.ac.ir/article_15279_6c7f85a28cbac4742afc6b7eac370c39.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521An efficient combination of Split-step in time and the Meshless local Petrov-Galerkin methods for solving the Ginzburg-Landau equation in two and three dimensionsAn efficient combination of Split-step in time and the Meshless local Petrov-Galerkin methods for solving the Ginzburg-Landau equation in two and three dimensions62871528010.22055/jamm.2020.28794.1695FAEsmailHesameddiniDepartment of Applied Mathematics, Shiraz University of Technology, Shiraz, IranAliHabibiradDepartment of Applied Mathematics, Shiraz University of Technology, Shiraz, IranJournal Article20190305In this paper, an efficient combination of the time-splitting and meshless local Petrov-Galerkin method for the numerical solution of Ginzburg–Landau equation in two and three dimensions is presented. The main idea of splitting scheme is separating the original equation in time into two parts, linear and nonlinear. Since, solving the nonlinear part based on the weak form is complicated and contains error, the split-step in time will be used. we solve the nonlinear part analytically and linear part numerically by the meshless local Petrov-Galerkin method in space variables and the Crank-Nicolson method in time. Hence, the moving Kriging interpolation is used instated of moving least squares. Therefore, the shape functions of the meshless local Petrov-Galerkin method have the Kronecker's delta property and the boundary conditions can be implemented directly and easily. Several examples for two and three dimensions are presented and the results are compared with their analytical solutions to demonstrate the validity and capability of this method.In this paper, an efficient combination of the time-splitting and meshless local Petrov-Galerkin method for the numerical solution of Ginzburg–Landau equation in two and three dimensions is presented. The main idea of splitting scheme is separating the original equation in time into two parts, linear and nonlinear. Since, solving the nonlinear part based on the weak form is complicated and contains error, the split-step in time will be used. we solve the nonlinear part analytically and linear part numerically by the meshless local Petrov-Galerkin method in space variables and the Crank-Nicolson method in time. Hence, the moving Kriging interpolation is used instated of moving least squares. Therefore, the shape functions of the meshless local Petrov-Galerkin method have the Kronecker's delta property and the boundary conditions can be implemented directly and easily. Several examples for two and three dimensions are presented and the results are compared with their analytical solutions to demonstrate the validity and capability of this method.https://jamm.scu.ac.ir/article_15280_8a5674a2245550390ad4f5f4d09525a9.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521Fractional-order Model for Cooling of a Semi-infinite Body by RadiationFractional-order Model for Cooling of a Semi-infinite Body by Radiation881051528110.22055/jamm.2020.28911.1697FAShahrokhEsmaeiliDepartment of Mathematics, University of Kurdistan, Sanandaj, Iran0000-0002-0584-6094Journal Article20190314In this paper, the fractional-order model for cooling of a semi-infinite body by radiation is considered.<br />In the supposed semi-infinite body, the equation of heat along with an initial condition and an asymptotic boundary condition form an equivalent equation in which the order of derivatives is halved.<br />This equation and a boundary condition introduced by the radiation heat transfer give rise to an initial value problem, whose differential equation is nonlinear and fractional order.<br />The semi-analytical solution to this nonlinear model was determined asymptotically at small and large times.<br />Moreover, two numerical methods including Grunwald-Letnikov approximation and Muntz-Legendre approximation yield numerical solutions to the problem.In this paper, the fractional-order model for cooling of a semi-infinite body by radiation is considered.<br />In the supposed semi-infinite body, the equation of heat along with an initial condition and an asymptotic boundary condition form an equivalent equation in which the order of derivatives is halved.<br />This equation and a boundary condition introduced by the radiation heat transfer give rise to an initial value problem, whose differential equation is nonlinear and fractional order.<br />The semi-analytical solution to this nonlinear model was determined asymptotically at small and large times.<br />Moreover, two numerical methods including Grunwald-Letnikov approximation and Muntz-Legendre approximation yield numerical solutions to the problem.https://jamm.scu.ac.ir/article_15281_94feec9fe604faf086e626c8718565f2.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521Estimation of the stress-strength parameter R=P(X>Y) in power Lindley distribution based on upper record valuesEstimation of the stress-strength parameter R=P(X>Y) in power Lindley distribution based on upper record values1061341528210.22055/jamm.2020.29827.1724FAAbbasPakDepartment of Computer Sciences, Shahrekord University, Shahrekord, IranAli AkbarJafariDepartment of Statistics, Yazd University, Yazd, Iran0000-0002-2980-338XMohammadrezaMahmoodiDepartment of Statistics, Fasa University, Fasa, IranJournal Article20190603In the literature, statistical estimation of the stress-strength reliability parameter R=P(X>Y) has attracted enormous interest. Recently, Ghitany et al. [7] studied statistical estimation of the parameter R in power Lindley distribution based on complete data sets. However, in practice, we may deal with record breaking data sets in which only values larger than the current extreme value are reported. In this paper, assuming that stress and strength random variables X and Y are independently distributed as power Lindley distribution, we consider estimation of the reliability parameter R based on upper record values. First, we obtain the maximum likelihood estimate of the reliability parameter and its asymptotic confidence interval. <br />Then, considering squared error and Linex loss functions, we compute the Bayes estimates of R. Since, there are not closed forms for the Bayes estimates, we use Lindley method as well as a Markov Chain Monte Carlo procedure to obtain approximate Bayes estimates. In order to evaluate the performances of the proposed procedures, simulation studies are conducted. Finally, by analyzing real data sets, application of the proposed inferences using upper records is presented.In the literature, statistical estimation of the stress-strength reliability parameter R=P(X>Y) has attracted enormous interest. Recently, Ghitany et al. [7] studied statistical estimation of the parameter R in power Lindley distribution based on complete data sets. However, in practice, we may deal with record breaking data sets in which only values larger than the current extreme value are reported. In this paper, assuming that stress and strength random variables X and Y are independently distributed as power Lindley distribution, we consider estimation of the reliability parameter R based on upper record values. First, we obtain the maximum likelihood estimate of the reliability parameter and its asymptotic confidence interval. <br />Then, considering squared error and Linex loss functions, we compute the Bayes estimates of R. Since, there are not closed forms for the Bayes estimates, we use Lindley method as well as a Markov Chain Monte Carlo procedure to obtain approximate Bayes estimates. In order to evaluate the performances of the proposed procedures, simulation studies are conducted. Finally, by analyzing real data sets, application of the proposed inferences using upper records is presented.https://jamm.scu.ac.ir/article_15282_9a0fbb05b4e9410b452811a3041fb642.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521The optimal scheme in type II progressive censoring with random removals for the Rayleigh distribution based on two-sample Bayesian prediction and cost functionThe optimal scheme in type II progressive censoring with random removals for the Rayleigh distribution based on two-sample Bayesian prediction and cost function1351571528310.22055/jamm.2020.29209.1705FAElhamBasiriDepartment of Mathematics and Applications, Faculty of Basic Sciences, Kosar University of Bojnord, Bojnord, IranSakineBeigiDepartment of Industrial Engineering, Kosar University of Bojnord, Bijnord, IranJournal Article20190418A type II progressive censoring scheme is one of the censoring methods that is important in life-testing studies. This method of censoring allows the experimenter to withdraw some of the tested units at different stages of testing. One question that arises when designing a type II progressive censoring is how we can decide to remove several units from the test at each step? Different answers can be made to answer this question by considering different criteria. In this paper, assuming the censoring scheme is a random variable from Binomial distribution, we intend to obtain the optimal parameter for the distribution of censoring scheme when the distribution is the Rayleigh distribution by considering two criteria, the cost of testing and the Mean squared prediction error in the two-sample prediction problem. To illustrate the effectiveness of the results, a simulation study and a real data example are presented with the help of MATLAB software.A type II progressive censoring scheme is one of the censoring methods that is important in life-testing studies. This method of censoring allows the experimenter to withdraw some of the tested units at different stages of testing. One question that arises when designing a type II progressive censoring is how we can decide to remove several units from the test at each step? Different answers can be made to answer this question by considering different criteria. In this paper, assuming the censoring scheme is a random variable from Binomial distribution, we intend to obtain the optimal parameter for the distribution of censoring scheme when the distribution is the Rayleigh distribution by considering two criteria, the cost of testing and the Mean squared prediction error in the two-sample prediction problem. To illustrate the effectiveness of the results, a simulation study and a real data example are presented with the help of MATLAB software.https://jamm.scu.ac.ir/article_15283_822108af3739562c0e8746b41c25ca10.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521The smallest class of subalgebras of a commutative BCK-algebra containing initial subsetsThe smallest class of subalgebras of a commutative BCK-algebra containing initial subsets1581711528410.22055/jamm.2020.28257.1678FAHabibHarizaviDepartment of Mathematics, Shahid Chamran University of Ahvaz, Ahvaz, IranTayebehKoochakpoorDepartment of Mathematics, Faculty of Sciences, Payame noor University, Tehran, IranJournal Article20190116In this paper, we assume that X is a BCK-algebra and y, t elements of X. We assign to these elements a set, denoted by F(y; t). We show that F(y; t) is a subalgebra of X. Then we prove that a BCK-algebra X is a Linear Commutative BCK-algebra if and only if every F(y; t) is an initial set of X. Moreover, we give a necessary and sufficient condition for F(y; t) to be an ideal. Finally, we show that the set consisting of all these sets forms a bounded distributive lattice.In this paper, we assume that X is a BCK-algebra and y, t elements of X. We assign to these elements a set, denoted by F(y; t). We show that F(y; t) is a subalgebra of X. Then we prove that a BCK-algebra X is a Linear Commutative BCK-algebra if and only if every F(y; t) is an initial set of X. Moreover, we give a necessary and sufficient condition for F(y; t) to be an ideal. Finally, we show that the set consisting of all these sets forms a bounded distributive lattice.https://jamm.scu.ac.ir/article_15284_abffccea422718552a5728d7e222399a.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521Stochastic Comparisons of Series and Parallel Systems arising from Lomax Components with Archimedean CopulaStochastic Comparisons of Series and Parallel Systems arising from Lomax Components with Archimedean Copula1721951528510.22055/jamm.2020.28651.1690FAGhobadBarmalzanDepartment of Statistics, University of Zabol, Zabol, IranMasihAyatDepartment of Mathematics, University of Zabol, Zabol, IranAbbasAkramiDepartment of Mathematics, University of Zabol, Zabol, IranJournal Article20190218This paper studies the usual stochastic, star and convex transform orders of both series and parallel systems comprised of heterogeneous (and dependent) components. Sufficient conditions are established for the star ordering between the lifetimes of series and parallel systems consisting of dependent<br />components having multiple-outlier lomax model. <br />We also prove that, without any restriction on the parameters, the lifetime of a parallel or series systems<br />with dependent heterogeneous components is smaller than that with dependent<br />homogeneous components in the sense of the convex transform order.This paper studies the usual stochastic, star and convex transform orders of both series and parallel systems comprised of heterogeneous (and dependent) components. Sufficient conditions are established for the star ordering between the lifetimes of series and parallel systems consisting of dependent<br />components having multiple-outlier lomax model. <br />We also prove that, without any restriction on the parameters, the lifetime of a parallel or series systems<br />with dependent heterogeneous components is smaller than that with dependent<br />homogeneous components in the sense of the convex transform order.https://jamm.scu.ac.ir/article_15285_a342f574834d9a2cb5e979a1ab0ed813.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521An extension of TOPSIS model based on monotonic utility of criteriaAn extension of TOPSIS model based on monotonic utility of criteria1962141529310.22055/jamm.2020.27384.1647FAAhmadKazemifardDepartment of Mathematics, Shahid Chamran University of Ahvaz, Ahvaz, IranJournal Article20181024Although TOPSIS is one of the widely used models in analyzing MCDM/MADM problems, there exists a necessary condition for its application that is the increasing or decreasing utility of the criteria. In the real world, in many cases, some of the criteria of decision making lack this property. In these cases an unrealistic assumption of the monotonic utility of the criteria is imposed to the model. However such an assumption may affect the accuracy of the results. This paper provides an extension of TOPSIS model which overcomes this limitation.Although TOPSIS is one of the widely used models in analyzing MCDM/MADM problems, there exists a necessary condition for its application that is the increasing or decreasing utility of the criteria. In the real world, in many cases, some of the criteria of decision making lack this property. In these cases an unrealistic assumption of the monotonic utility of the criteria is imposed to the model. However such an assumption may affect the accuracy of the results. This paper provides an extension of TOPSIS model which overcomes this limitation.https://jamm.scu.ac.ir/article_15293_4a4489ef246caf884cb07ddfabab9c8f.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521An integer-valued bilinear time series model via random Pegram and thinning operatorsAn integer-valued bilinear time series model via random Pegram and thinning operators2152301531510.22055/jamm.2020.28321.1679FAMehrnazMohammadpourDepartment of Statistics, University of Mazandaran, Mazandran, IranSakinehRamezaniDepartment of Statistics, University of Mazandaran, Mazandran, IranJournal Article20190121In this paper, we introduce a new integer valued bilinear modeling based on the Pegram and thinning operators. Some statistical properties of the model are discussed. The model parameters are estimated by the conditional least square and Yule-Walker methods. By a simulation, the performances of the two estimation methods are studied. Finally, the efficiency of the proposed model is investigated by applying it on two real data sets.In this paper, we introduce a new integer valued bilinear modeling based on the Pegram and thinning operators. Some statistical properties of the model are discussed. The model parameters are estimated by the conditional least square and Yule-Walker methods. By a simulation, the performances of the two estimation methods are studied. Finally, the efficiency of the proposed model is investigated by applying it on two real data sets.https://jamm.scu.ac.ir/article_15315_27fb726d266c6ad96bc9924fb1a7baac.pdfShahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-808810120200521Adomian Decomposition Method in Solving of Falkner-Skan Boundary Layer EquationAdomian Decomposition Method in Solving of Falkner-Skan Boundary Layer Equation2312441540510.22055/jamm.2020.15405FAShahramRezapourDepartment of Mathematics,, Azarbaidjan Shahid Madani University, Tabriz, IranHakimehMohammadiDepartment of Mathematics, Miandoab Branch, Islamic Azad University, Miandoab, IranJournal Article20181102In this paper an analytical technique, namely the adomian decomposition method (ADM), has been applied to solve the governing equations for boundary- Layer problems in the case of a two dimensional incompressible flow. In the present work, Falkner-Skan equation for special circumstances (Blasius flow, Stagnation point flow, flow in a convergent channel, flow over a wedge) has been solved. It is found that this method can give very accurate results and also it is powerful mathematical tool that can be applied to a large class of Linear and nonlinear problems in different fields of science and engineering.In this paper an analytical technique, namely the adomian decomposition method (ADM), has been applied to solve the governing equations for boundary- Layer problems in the case of a two dimensional incompressible flow. In the present work, Falkner-Skan equation for special circumstances (Blasius flow, Stagnation point flow, flow in a convergent channel, flow over a wedge) has been solved. It is found that this method can give very accurate results and also it is powerful mathematical tool that can be applied to a large class of Linear and nonlinear problems in different fields of science and engineering.https://jamm.scu.ac.ir/article_15405_566c9898ea032c28c3e54c8c5e7271b2.pdf