Dear Label_Name,

Greetings! I hope you are well.

I am writing on behalf of an international publishing house, Science and Education Publishing, USA (http://www.sciepub.com).

Science and Education Publishing (SciEP) is a multidisciplinary open access publisher of Journals covering the fields of Science, Technology and Medicine. All SciEP publications are subject to high-quality peer review, editorial and production processes and are freely available online.

Welcome to the April, 2013 edition of SciEP newsletter, providing monthly summaries of articles on science & education related topics of interest to scientist and professionals. The mission of our journals is to provide an open access forum for publishing new findings on issues pertinent to scientific and academic field. We also invite you to submit original research papers, review articles, short reports, or case studies are considered for publication in our Multidisciplinary Journals.

American Journal of Public Health Research
DOI: 10.12691/ajphr-1-1-3

The Implementation of a Tele-Homecare System with Service Oriented Architecture and HL7 Message Transmission Standard
Ching-Sung Wang

American Journal of Medical and Biological Research
DOI: 10.12691/ajmbr-1-1-2

The Influence of Ethanol on Pyruvate Kinases Activity in Vivo, in Vitro, in Silico
Lelevich Sergey Vladimirovich, Khrustalev Vladislav Victorovich, Barkovsky Eugene Victorovich, Shedogubova Tatyana Aleksandrovna

American Journal of Medical Sciences and Medicine
DOI: 10.12691/ajmsm-1-1-1

Clinical and Histological Features in Wegener Granulomatosis
Li Cavoli Gioacchino, Passantino Rita, Bono Luisa, Tortorici Calogera, Ferrantelli Angelo, Giammarresi Carlo, Rotolo Ugo

American Journal of Infectious Diseases and Microbiology
DOI: 10.12691/ajidm-1-1-2

The Curse of Lymphatic Filariasis: Would the Continual Use of Diethylcarbamazine Eliminate this Scourge in Papua New Guinea?
Anne Lanham, Lillian Mwanri

We have released issues of some journals on February 2013.
American Journal of Public Health Research
American Journal of Medical Sciences and Medicine
American Journal of Medical and Biological Research
American Journal of Pharmacological Sciences
American Journal of Clinical Medicine Research
American Journal of Nursing Research
American Journal of Cancer Prevention
American Journal of Medicine Studies
American Journal of Infectious Diseases and Microbiology
American Journal of Cardiovascular Disease Research
American Journal of Biomedical Research
American Journal of Mechanical Engineering
American Journal of Microbiological Research
Journal of Preventive Medicine
American Journal of Food and Nutrition
American Journal of Hypertension Research
American Journal of Sports Science and Medicine
Journal of Cancer Research and Treatment
American Journal of Zoological Research
Journal of Biomedical Engineering and Technology
American Journal of Microbiological Research
Biomedical Science and Engineering

We are pleased to announce that submissions are now being accepted for peer review for all the journals across all our subject areas in SciEP.

Please submit your manuscript via our online submission system:
http://www.sciepub.com/author/signin

To unsubscribe from our mailing list, please click on the following link: unsubscribe

I am looking forward to hearing from you.

Kind regards,

David Rain
Email:join@sciepub.com
Science and Education Publishing (http://www.sciepub.com)

A Priori Error Analysis and Numerical Simulation of Fully Discrete H¹-Galerkin Mixed Element Method for Nonlinear Pseudo-Hyperbolic Equation

Guoyu Zhang, Lijun Huang, Zudeng Yu, Yang Liu*, Hong Li*, Min Zhang

School of Mathematical Sciences, Inner Mongolia University, Hohhot, ChinaSchool of Mathematical Sciences, Inner Mongolia University, Hohhot, China

Abstract: In this article, a fully discrete two-step H¹-Galerkin mixed method is presented for nonlinear pseudo-hyperbolic equation. The spatial direction and time direction are approximated by H¹-Galerkin mixed method and two-step difference method, respectively. Some a priori error results are analyzed for the scalar unknown function u and its flux . Moreover, a numerical test is made to verify our theoretical error analysis.

Keywords: two-step discrete method, H¹-Galerkin mixed method, nonlinear pseudo-hyperbolic equation, a priori error analysis, fully discrete scheme

Received January 26, 2014; Revised February 20, 2014; Accepted February 28, 2014

Citation: Guoyu Zhang, Lijun Huang, Zudeng Yu, Yang Liu, Hong Li, Min Zhang, A Priori Error Analysis and Numerical Simulation of Fully Discrete H¹-Galerkin Mixed Element Method for Nonlinear Pseudo-Hyperbolic Equation. American Journal of Numerical Analysis, 2 (2). 55-59. January 2014. doi:10.12691/ajna-2-2-4

1. Introduction

In this article, we consider the following nonlinear pseudo-hyperbolic equation [1-9] with initial and boundary conditions

[picture] | (1)

where is a bounded domain in, which boundary is smooth. The initial values and are known functions, the coefficient is a bounded and smooth function. is a nonlinear bounded function of with and a bounded derivative.

As we know, the pseudo-hyperbolic equations, which describe many physical phenomena, such as heat and mass transfer and nerve conduction, are a kind of important hyperbolic wave equations. In view of the importance of the pseudo-hyperbolic equations, a lot of numerical methods have been studied, such as splitting positive definite mixed element method [1,2], least-squares mixed element method [3,4], H¹-Galerkin mixed element methods [5,6,7,8], mixed covolume method [9] and so forth.

Pani [10] presented and analyzed an H¹-Galerkin mixed method for solving the linear parabolic equation with initial and boundary condition and derived some semi-discrete and fully discrete a priori error results in detail. This method holds some good features: free of LBB condition, the freedom of approximation space’s selection and the better order of convergence for the flux in L²-norm. Based on the above value points, the H¹-Galerkin mixed element method for many evolution equations (pseudo-hyperbolic equations [5,6], integro-differential equation [11], hyperbolic equation [12], Sobolev equation [13], RLW equation [14,15], Schrodinger equation [16], Burgers’ equation [20]) were formulated. At the same time, some good numerical methods (Nonconforming H¹-Galerkin mixed method [7,17], Splitting H¹-Galerkin mixed method [8], H¹-Galerkin expanded mixed methods [18,19]) based on the H¹-Galerkin mixed element method were developed by many authors. Liu and Li [5], Zhou [6] gave the theoretical analysis of a priori errors for H¹-Galerkin mixed method, respectively. Zhang et al. [7] studied a semi-discrete nonconforming H¹-Galerkin mixed scheme. Liu et al. [8] proposed a new splitting H¹-Galerkin mixed method, then analyzed a Crank-Nicolson fully discrete a priori error results. But in [5,6,7,8], the considered pseudo-hyperbolic equation is only a linear problem.

In this article, our aim is to consider a nonlinear pseudo-hyperbolic problem and to propose a fully discrete two-step difference method combining with an H¹-Galerkin mixed element method. Compared to backward Euler discrete method [5,6] based on the linear problem, our method get some optimal second-order results of convergence in time direction for nonlinear pseudo-hyperbolic equation (1). As far as we know, the study of the H¹-Galerkin mixed method based on two-step difference scheme is fairly limited in the literatures, so our study is meaningful. We will give some a priori error analysis in detail and make some numerical simulation.

2. Two-Step Mixed Scheme and A Priori Error Estimates

2.1. Mixed Weak Formulation

By a similar selection to [5,6], we consider an auxiliary variable , then (1) can be split into a coupled system by:

[picture] | (2)

In (2), by making an inner product for () and (), respectively, we use Green’s formula to obtain the mixed weak formulation: find:such that:

[picture] | (3)

where .

2.2. Fully Discrete Scheme and Some Important Lemmas

We give a partition with mesh length , (is a positive integer) of the time interval . Furthermore, we define for a smooth function on. In the following, we will get two-step time discrete scheme based on the above expression.

At , we get an equivalent form of (3) as follows:

[picture] | (4)

By two-step discrete method, (4) can be rewritten as:

[picture] | (5)

where

[picture] | (6)

Based on the weak formulation (5), the fully discrete two-step mixed scheme is to find in

such that

[picture] | (7)

We now introduce two important lemmas with and to analyze some a priori error results

Lemma 1 [10,21] Define a Ritz projection of by:

[picture] | (8)

and the estimates hold

[picture] | (9)

Lemma 2 [10] Let be the standard finite element interpolant of , then holds

[picture] | (10)

For the need for error analysis, we decompose

Combine (5) and (7) with (8) to get the error equations:

[picture] | (11)

and

[picture] | (12)

Lemma 3 [15] For , and , the following errors hold:

[picture] | (13)

[picture] | (14)

[picture] | (15)

Lemma 4 [15] For a sequenceand bounded function, the following equality holds

[picture] | (16)

2.3. The Error Estimates of Two-step Mixed Element

Theorem 1 Assuming that and , then, for hold

[picture] | (17)

[picture] | (18)

Proof: Set in (11) and use lemma 4 to get

[picture] | (19)

By the application for Cauchy-Schwarz inequality and Young inequality, we arrive at

[picture] | (20)

Multiply in (20), sum to and use lemma 3 to get

[picture] | (21)

By an application for Poincare inequality, we have

[picture] | (22)

We set in (12) to get

[picture] | (23)

Apply Cauchy-Schwarz inequality and Young inequality to get

[picture] | (24)

Use lemma 4 to get

[picture] | (25)

Using differential mean value theorem, we have for and

[picture] | (26)

As the result in [15], we have

[picture] | (27)

Substitute (25)-(27) into (24) and note that lemma 3 to get

[picture] | (28)

Multiply in (28), sum to and use (22) to get

[picture] | (29)

By a combination of (9) and (10) with Gronwall lemma, we have

[picture] | (30)

Substitute (30) into (21) and (22) to get

[picture] | (31)

By a combination (28), (31), (9) and (10) with triangle inequality, we get the conclusion of theorem 1.

3. Numerical Test

In this section, for verifying the theoretical analysis, we take 1-D nonlinear pseudo-hyperbolic equation with space-time domain

[picture] | (32)

where the exact solution is and is determined by the exact solution.

We choose the piecewise linear space in the spatial direction and two-step difference scheme in time direction and give some numerical results by Matlab procedure. In Table 1, we list some a priori error results for and in L²-norm with space-time step length . From Table 1, we can clearly see that the rate of convergence for our method is close to 2, which confirms our theoretical error results.

In Figure 1, the comparison figures are shown for the exact solution and the numerical solution . The similar results for and are also described in Figure 2. From Figure 1 and Figure 2, we can intuitively see that the proposed numerical method is feasible and effective.

Table 1. Optimal errors in L∞ (L²) norm

Figure 1. Exact solution u and numerical solution un

Figure 2. Exact solution q and numerical solution qn

4. Some Conclusions and Remarks

So far, the H¹-Galerkin mixed element method [10] has been considered to seek for the numerical solutions by more and more people. In the literatures on the H¹-Galerkin mixed method, the backward Euler method and Crank-Nicolson scheme are widely presented. However, the two-step difference method based on the H¹-Galerkin mixed method is sparingly studied and analyzed. In this article, we consider a two-step difference method in time direction combining H¹-Galerkin mixed method and obtain some optimal time second-order rates of convergence.

From the results of numerical calculations, we can clearly find that fully discrete two-step H¹-Galerkin mixed method is efficient. In the near future, the fully discrete two-step difference method combined with H¹-Galerkin mixed method for nonlinear pseudo-hyperbolic integro-differential equations is analyzed.

Acknowledgement

In this paper, the research was sponsored by the National Natural Science Fund (Project No. 11301258; 11361035), Natural Science Fund of Inner Mongolia Autonomous Region (Project No. 2012MS0108; 2012MS0106), Scientific Research Projection of Higher Schools of (Project No. NJZZ12011; NJZY13199) and The National Undergraduate Innovative Training Project (201310126040).

References

[1]   | Y. Liu, H. Li, J.F. Wang, S. He. Splitting positive definite mixed element methods for pseudo-hyperbolic equations. Numer. Methods Partial Differential Equations, 28(2), (2012), 670-688.
[2]   | D.Y. Shi, Q.L. Tang, Superconvergence analysis of splitting positive definite nonconforming mixed finite element method for pseudo-hyperbolic equations, Acta Mathematicae Applicatae Sinica, English Series, 29(4), (2013), 843-854.
[3]   | H. Guo, Analysis of split weighted least-squares procedures for pseudo-hyperbolic equations, Appl. Math. Comput., 217(8), (2010), 4109-4121.
[4]   | H. Guo, H.X. Rui, Least-squares Galerkin procedures for pseudo-hyperbolic equations, Appl. Math. Comput., 189, (2007), 425-439.
[5]   | Y. Liu, H. Li, H¹-Galerkin mixed finite element methods for pseudo-hyperbolic equations, Appl. Math. Comput., 212(2), (2009) 446-457.
[6]   | Z. J. Zhou, An H¹-Galerkin mixed finite element method for a class of heat transport equations, Appl. Math. Model., 34 (2010), 2414-2425.
[7]   | Y.D. Zhang, Y.Q. Niu, D.W. Shi. Nonconforming H¹-Galerkin mixed finite element method for pseudo-hyperbolic equations, American Journal of Computational Mathematics, 2, (2012), 269-273.
[8]   | Y. Liu, J.F. Wang, H. Li, W. Gao, S. He, A new splitting H¹-Galerkin mixed method for pseudo-hyperbolic equations, World Academy of Science, Engineering and Technology, 51, (2011), 1444-1449.
[9]   | Z.C. Fang, H. Li, Z.D. Luo, A mixed covolume method for pseudo-hyperbolic equation, Acta Mathematica Scientia, 33A(3), (2013), 535-550
[10]   | A.K. Pani, An H¹-Galerkin mixed finite element method for parabolic partial differential equations, SIAM J. Numer. Anal. 35, (1998), 712-727.
[11]   | A.K. Pani, G. Fairweather, H¹-Galerkin mixed finite element methods for parabolic partial integro-differential equations. IMA Journal of Numerical Analysis, 22, (2002), 231-252.
[12]   | A.K. Pani, R.K. Sinha, A.K. Otta. An H¹-Galerkin mixed method for second order hyperbolic equations, International Journal of Numerical Analysis and Modeling, 1(2), (2004), 111-129.
[13]   | L. Guo, H.Z. Chen, H¹-Galerkin mixed finite element method for Sobolev equations, J. Sys. Sci. Math. Scis., 26(3), (2006), 301-314.
[14]   | L. Guo, H.Z. Chen, H¹-Galerkin mixed finite element method for the regularized long wave equation, Computing, 77, (2006), 205-221.
[15]   | Y. Liu, H. Li, Y. W. Du, and J. F. Wang, Explicit multistep mixed finite element method for RLW equation, Abstract and Applied Analysis, Volume 2013, Article ID 768976, 12 pages.
[16]   | Y. Liu, H. Li, J.F. Wang. Error estimates of H¹-Galerkin mixed finite element method for Schrodinger equation, Appl. Math. J. Chinese Univ., 24(1), (2009), 83-89.
[17]   | D.Y. Shi, H.H. Wang, Nonconforming H¹-Galerkin mixed FEM for Sobolev equations on anisotropic meshes, Acta Mathematicae Applicatae Sinica(English Series), 25(2), (2009), 335-344.
[18]   | H.Z. Chen, H. Wang, An optimal-order error estimate on an H¹-Galerkin mixed method for a nonlinear parabolic equation in porous medium flow, Numerical Methods for Partial Differential Equations, 26(1) (2010) 188-205.
[19]   | H.T. Che, Z.J. Zhou, Z.W. Jiang, Y.J. Wang, H¹-Galerkin expanded mixed finite element methods for nonlinear pseudo-parabolic integro-differential equations, Numer. Methods for Partial Differential Equations, 29(3), (2013), 799-817.
[20]   | A.K. Pany, N. Nataraj, S. Singh, A new mixed finite element method for burgers equation, J. Appl. Math. Comput., 23(1-2) (2007), 43-55.
[21]   | Z D Luo. Theory Bases and Applications of Finite Element Mixed Methods, Science Press, Beijing, 2006.