Shahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-80885120151122Meshfree method for solving mathematical fractional order model of capillary formation in tumor
angiogenesisMeshfree method for solving mathematical fractional order model of capillary formation in tumor
angiogenesis1181149410.22055/jamm.2015.11494FABahmanGhazanfariDepartment of Mathematics, Lorestan UniversityAminShahkaramiDepartment of Mathematics, Lorestan UniversityJournal Article20150406This paper was devoted to numerical solution of capillary formation in tumor angiogenesis with time fractional derivative. A time discretization approach based on the θ-weighted fractional finite difference scheme was employed for time fractional derivative and a mesh free process was applied by using radial basis functions (RBFs). Stability analysis of the method was also investigated and some numerical cases were studied.This paper was devoted to numerical solution of capillary formation in tumor angiogenesis with time fractional derivative. A time discretization approach based on the θ-weighted fractional finite difference scheme was employed for time fractional derivative and a mesh free process was applied by using radial basis functions (RBFs). Stability analysis of the method was also investigated and some numerical cases were studied.Shahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-80885120151122General progressive joint Type-II censoring scheme and inference for parameters of two Weibull populations under this schemeGeneral progressive joint Type-II censoring scheme and inference for parameters of two Weibull populations under this scheme19381149010.22055/jamm.2015.11490FAHamzehTorabiDepartment of Statistics, Yazd University0000-0002-4200-9770SaeedehBafekri FadafenDepartment of Statistics, Yazd UniversityHosseinNadebDepartment of Statistics, Yazd UniversityJournal Article20150406In this paper, a generalization of the progressive joint Type-II censoring scheme is introduced. Application of this scheme is in the case that the lifetimes of first units of two samples are missing or lost and also because of preventing of long time of the test, some units are removed during the test. After introducing the scheme, for parameters of two Weibull populations, maximum likelihood estimators and confidence interval using procedures such as asymptotic normality and bootstrap methods, under the scheme, are obtained. Finally, by means a simulation study these estimations are evaluated and also all confidence intervals are compared in terms of coverage probabilities.In this paper, a generalization of the progressive joint Type-II censoring scheme is introduced. Application of this scheme is in the case that the lifetimes of first units of two samples are missing or lost and also because of preventing of long time of the test, some units are removed during the test. After introducing the scheme, for parameters of two Weibull populations, maximum likelihood estimators and confidence interval using procedures such as asymptotic normality and bootstrap methods, under the scheme, are obtained. Finally, by means a simulation study these estimations are evaluated and also all confidence intervals are compared in terms of coverage probabilities.Shahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-80885120151122Maximum M-Entropy model- type ΙΙ for obtaining the ordered weighted averaging operator weightsMaximum M-Entropy model- type ΙΙ for obtaining the ordered weighted averaging operator weights39581149110.22055/jamm.2015.11491FAAlirezaChajiShohadaie Hovaizeh University of Technology, Susangerd, IranGholamhoussainYariDepartment of Mathematics, Iran University of Science and TechnologyJournal Article20141213One key issue in the theory of the OWA operator is to determine its associated weights. In this paper, based upon the M-Entropy measures, new models for obtaining the ordered weighted averaging (OWA) operators are proposed. In the models it is assumed, according to available information that the OWA weights are in decreasing or increasing order. Some properties of the models are analyzed and the method of Lagrange multipliers is used to provide a direct way to find these weights. The models are solved with specific level of Orness comparing the results with some other related models and with the other maximum M-entropy model. The results demonstrate the efficiency of the M-Entropy models in generating the OWA operator weights. Also, the obtained weights of the two M-entropy models confirm the difference between two types of the models. Finally, an applied example is presented to illustrate the applications of the proposed model.One key issue in the theory of the OWA operator is to determine its associated weights. In this paper, based upon the M-Entropy measures, new models for obtaining the ordered weighted averaging (OWA) operators are proposed. In the models it is assumed, according to available information that the OWA weights are in decreasing or increasing order. Some properties of the models are analyzed and the method of Lagrange multipliers is used to provide a direct way to find these weights. The models are solved with specific level of Orness comparing the results with some other related models and with the other maximum M-entropy model. The results demonstrate the efficiency of the M-Entropy models in generating the OWA operator weights. Also, the obtained weights of the two M-entropy models confirm the difference between two types of the models. Finally, an applied example is presented to illustrate the applications of the proposed model.Shahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-80885120151122A 3-D Mathematical Modeling in Solving Analytical Consolidation Equation in a Homogeneous Saturated SoilA 3-D Mathematical Modeling in Solving Analytical Consolidation Equation in a Homogeneous Saturated Soil59741148710.22055/jamm.2015.11487FARezaPoursakiDepartment of Water Sciences Engineering, Shahid Chamran UniversityJavaAhadianDepartment of Water Sciences Engineering, Shahid Chamran UniversityMansourSerajDepartment of Mathematics, Shahid Chamran UniversityJournal Article20151215The drainage length can be artificially decreased using vertical drains where need to accelerate in the consolidation settlement, so that the flow can be drained radially and vertically. In this research, the three dimensional consolidation equation with appropriate boundary conditions was used in cylindrical coordinates, and then was solved analytically. After the analytical solution, analysis of the results was done on using MATLAB software. Moreover, the average degree of consolidation versus time was obtained and compared with the results of one-dimensional method. Findings showed that, the analytical method in this research is in accordance with another numerical method in the previous researches.The drainage length can be artificially decreased using vertical drains where need to accelerate in the consolidation settlement, so that the flow can be drained radially and vertically. In this research, the three dimensional consolidation equation with appropriate boundary conditions was used in cylindrical coordinates, and then was solved analytically. After the analytical solution, analysis of the results was done on using MATLAB software. Moreover, the average degree of consolidation versus time was obtained and compared with the results of one-dimensional method. Findings showed that, the analytical method in this research is in accordance with another numerical method in the previous researches.Shahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-80885120151122Probabilistic Modeling of Wind Direction Data Related to Meteorological Stations of Kurdistan Province Using Skew Circular DistributionsProbabilistic Modeling of Wind Direction Data Related to Meteorological Stations of Kurdistan Province Using Skew Circular Distributions75881149210.22055/jamm.2015.11492FAMousaGolalizadehDepartment of Statistics, University of Tarbiat ModaresHamidrezaMosaferi GhomikolaeeDepartment of Statistics, University of Tarbiat ModaresJournal Article20150417In studying some phenomena, the researchers are usually encountered with data that are not Euclidean in nature. To investigate the properties of these data, it is required to use some new statistical tools. Statistical methods to analysis these typical data are called non-linear statistics. Circular statistics is an example of this field. After explaining some circular distributions that are able to model skew circular data, probabilistic modeling of wind direction data related to meteorological stations of Kurdistan province is studied in this paper.In studying some phenomena, the researchers are usually encountered with data that are not Euclidean in nature. To investigate the properties of these data, it is required to use some new statistical tools. Statistical methods to analysis these typical data are called non-linear statistics. Circular statistics is an example of this field. After explaining some circular distributions that are able to model skew circular data, probabilistic modeling of wind direction data related to meteorological stations of Kurdistan province is studied in this paper.Shahid Chamran University of AhvazJournal of Advanced Mathematical Modeling2251-80885120151122Numerical simulation of natural convection heat transfer in a horizontal annulus with discrete heating using mesh-free lattice-Boltzmann methodNumerical simulation of natural convection heat transfer in a horizontal annulus with discrete heating using mesh-free lattice-Boltzmann method891121149310.22055/jamm.2015.11493FAAbdolrahmanDadvandDepartment of Mechanical Engineering, Urmia University of TechnologyAhmadHaghighiDepartment of Mathematics, Urmia University of TechnologyHamidehHoseini GhejloDepartment of Mathematics, Urmia University of TechnologyJournal Article20141201This study investigates the natural convection heat transfer in a horizontal annulus with discrete heating using a mesh-free lattice Boltzmann method. The lattice Boltzmann method has become an alternative to the conventional computational fluid dynamics methods for simulation of complex fluid flows. The major advantages of the lattice Boltzmann method are the explicit feature of the governing equation, easy for parallel computation, and simple implementation of boundary conditions on curved boundaries. Despite well viability of standard LBM for the uniform mesh, it cannot be directly applied to problems with complex geometry and non-uniform mesh. An efficient method for removing this limitation is to use Taylor series expansion and least squares-based LBM (TLLBM). The final form of the TLLBM is an algebraic formulation with no limitation on the mesh structure. This method can also be applied to any lattice velocity model. In the present work, the TLLBM with D2Q9 lattice model is used to simulate natural convection heat transfer in a horizontal annulus with discrete heating. The effects of Rayleigh number and different arrangement of two heat source-sink pairs on the fluid flow and heat transfer characteristics are investigated.This study investigates the natural convection heat transfer in a horizontal annulus with discrete heating using a mesh-free lattice Boltzmann method. The lattice Boltzmann method has become an alternative to the conventional computational fluid dynamics methods for simulation of complex fluid flows. The major advantages of the lattice Boltzmann method are the explicit feature of the governing equation, easy for parallel computation, and simple implementation of boundary conditions on curved boundaries. Despite well viability of standard LBM for the uniform mesh, it cannot be directly applied to problems with complex geometry and non-uniform mesh. An efficient method for removing this limitation is to use Taylor series expansion and least squares-based LBM (TLLBM). The final form of the TLLBM is an algebraic formulation with no limitation on the mesh structure. This method can also be applied to any lattice velocity model. In the present work, the TLLBM with D2Q9 lattice model is used to simulate natural convection heat transfer in a horizontal annulus with discrete heating. The effects of Rayleigh number and different arrangement of two heat source-sink pairs on the fluid flow and heat transfer characteristics are investigated.