 
								A High Order Compact ADI Method for Solving 3D Unsteady Convection Diffusion Problems
								
									
										
											
											
												Yongbin Ge,
											
										
											
											
												Fei Zhao,
											
										
											
											
												Jianying Wei
											
										
									
								 
								
									
										Issue:
										Volume 7, Issue 1, February 2018
									
									
										Pages:
										1-10
									
								 
								
									Received:
										3 December 2017
									
									Accepted:
										13 December 2017
									
									Published:
										12 January 2018
									
								 
								
								
								
									
									
										Abstract: In this paper, we develop a rational high order compact alternating direction implicit (RHOC ADI) method for solving the three dimensional (3D) unsteady convection diffusion equation. The present scheme, based on the idea of the fourth order rational compact finite difference operator for the spatial discretization and the Crank-Nicolson method for the time discretization, is fourth order accurate in space and second order accurate in time. The solution procedure consists of a number of tridiagonal matrix operations, which makes the computation to be cost-effective. It is shown by means of the discrete Fourier analysis that this method is unconditionally stable. Three test problems are given to demonstrate the performance of the present method. The numerical results show that the present RHOC ADI scheme has higher accuracy and better phase and amplitude error characteristics than the classical second order Douglas-Gunn ADI method [16] and some high order compact ADI methods including the Karaa’s HOC ADI method [26], Cao and Ge’s HOC ADI method [27], and our previous exponential HOC ADI method [28].
										Abstract: In this paper, we develop a rational high order compact alternating direction implicit (RHOC ADI) method for solving the three dimensional (3D) unsteady convection diffusion equation. The present scheme, based on the idea of the fourth order rational compact finite difference operator for the spatial discretization and the Crank-Nicolson method for...
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								A Stable and Convergent Finite Difference Scheme for 2D Incompressible Nonlinear Viscoelastic Fluid Dynamics Problem
								
								
									
										Issue:
										Volume 7, Issue 1, February 2018
									
									
										Pages:
										11-18
									
								 
								
									Received:
										4 December 2017
									
									Accepted:
										15 December 2017
									
									Published:
										12 January 2018
									
								 
								
								
								
									
									
										Abstract: In this study, a stable and convergent finite difference (FD) scheme based on staggered meshes for two-dimensional (2D) incompressible nonlinear viscoelastic fluid dynamics problem including the velocity vector field and the pressure field as well as the deformation tensor matrix is established in order to find numerical solutions for the problem. The stability, convergence, and errors of the FD solutions are analyzed. Some numerical experiments are presented to show that the FD scheme is feasible and efficient for simulating the phenomena of the velocity and the pressure as well as the deformation tensor in an estuary.
										Abstract: In this study, a stable and convergent finite difference (FD) scheme based on staggered meshes for two-dimensional (2D) incompressible nonlinear viscoelastic fluid dynamics problem including the velocity vector field and the pressure field as well as the deformation tensor matrix is established in order to find numerical solutions for the problem. ...
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								A Reduced-Order Extrapolating Finite Difference Iterative Scheme for 2D Generalized Nonlinear Sine-Gordon Equation
								
									
										
											
											
												Hong Xia,
											
										
											
											
												Fei Teng,
											
										
											
											
												Zhendong Luo
											
										
									
								 
								
									
										Issue:
										Volume 7, Issue 1, February 2018
									
									
										Pages:
										19-25
									
								 
								
									Received:
										17 December 2017
									
									Accepted:
										2 January 2018
									
									Published:
										18 January 2018
									
								 
								
								
								
									
									
										Abstract: In this study, a reduced-order extrapolating finite difference iterative (ROEFDI) scheme holding sufficiently high accuracy but containing very few degrees of freedom for the two-dimensional (2D) generalized nonlinear Sine-Gordon equation is built via the proper orthogonal decomposition. The stability and convergence of the ROEFDI solutions are analyzed. And the feasibility and effectiveness of the ROEFDI scheme are verified by numerical simulations. This means that the ROEFDI scheme is effective and feasible for finding the numerical solutions of the 2D generalized nonlinear Sine-Gordon equation.
										Abstract: In this study, a reduced-order extrapolating finite difference iterative (ROEFDI) scheme holding sufficiently high accuracy but containing very few degrees of freedom for the two-dimensional (2D) generalized nonlinear Sine-Gordon equation is built via the proper orthogonal decomposition. The stability and convergence of the ROEFDI solutions are ana...
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								Topological Structure of Riesz Sequence Spaces
								
									
										
											
											
												Merve Temizer Ersoy,
											
										
											
											
												Bilal Altay,
											
										
											
											
												Hasan Furkan
											
										
									
								 
								
									
										Issue:
										Volume 7, Issue 1, February 2018
									
									
										Pages:
										26-30
									
								 
								
									Received:
										29 December 2017
									
									Accepted:
										12 January 2018
									
									Published:
										20 January 2018
									
								 
								
								
								
									Abstract: In this paper, to be the Riesz matrix is symbolized by 

, it is defined the spaces 

 and 

 where for instance 

 and computed its duals (
α-dual, 
β-dual and 
γ-dual). Furthermore, it is investigated topological structure of 

 and determined necessary and sufficient conditions for a matrix 

 to map 

, or 

 into 

 or 

.