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1.
In this paper, we deal with the global existence and nonexistence of solutions to a nonlinear diffusion system coupled via nonlinear boundary flux. By constructing various kinds of sub- and super-solutions and using the basic properties of M-matrix, we give the necessary and sufficient conditions for global existence of nonnegative solutions. The critical curve of Fujita type is conjectured with the aid of some new results, which extend the recent results of Wang et al. [Nonlinear Anal. 71 (2009) 2134-2140] and Li et al. [J. Math. Anal. Appl. 340 (2008) 876-883] to more general equations.  相似文献   

2.
We prove the existence of solutions for the great lake equations. These equations are obtained from the three-dimensional Euler equations in a basin with a free upper surface and a spatially varying bottom topography by taking a low aspect ratio, i.e., low wave speed and small wave amplitude expansion. These equations are rewritten in an abstract form by considering generalized Euler equations as in Levermore et?al. (Indiana Univ Math J 45:479?C510, 1996). This paper is an extension of Levermore et?al. (Indiana Univ Math J 45:479?C510, 1996), where the varying bottom was assumed to be nondegenerate. Here, we discuss the degenerate case and obtain similar results as in Levermore et?al. (Indiana Univ Math J 45:479?C510, 1996).  相似文献   

3.
In the present paper, a Lotka–Volterra type mutualism system with several delays is studied. Some new and interesting sufficient conditions are obtained for the global existence of positive periodic solutions of the mutualism system. Our method is based on Mawhin’s coincidence degree and novel estimation techniques for the a priori bounds of unknown solutions. Our results are different from the existing ones such as those in of Yang et al. [F. Yang, D. Jiang, A. Ying, Existence of positive solution of multidelays facultative mutualism system, J. Eng. Math. 3 (2002) 64–68] and Chen et al. [F. Chen, J. Shi, X. Chen, Periodicity in a Lotka–Volterra facultative mutualism system with several delays, J. Eng. Math. 21 (3) (2004) 403–409].  相似文献   

4.
We consider the model that has been suggested by Greenberg et al. (Physica D 134 (1999) 362-383) for the ferroelectric behavior of materials. In this model, the usual (linear) Maxwell's equations are supplemented with a constitutive relation in which the electric displacement equals a constant times the electric field plus an internal polarization variable which evolves according to an internal set of nonlinear Maxwell's equations. For such model we provide rigorous proofs of global existence, uniqueness, and regularity of solutions. We also provide some preliminary results on the long-time behavior of solutions. The main difficulties in this study are due to the loss of compactness in the system of Maxwell's equations. These results generalize those of Greenberg et al., where only solutions with TM (transverse magnetic) symmetry were considered.  相似文献   

5.
This paper deals with a periodic boundary value problem for a second order functional differential equation. We obtain the existence of extreme solutions under new concept of upper and lower solutions. Also, a mistake in a recent paper (Ding et al. in J. Math. Anal. Appl. 298:341–351, 2004) is corrected.  相似文献   

6.
We investigate the existence of self-similar solutions for a coagulation equation with nonlocal drift. In addition to explicitly given exponentially decaying solutions we establish the existence of self-similar profiles with algebraic decay. To cite this article: M. Herrmann et al., C. R. Acad. Sci. Paris, Ser. I 347 (2009).  相似文献   

7.
In this paper, we apply our new results on quasi-variational inequality problems to generalized quasi-equilibrium problems. Some su?cient conditions on the existence of solutions are shown. In particular, we establish several results on the existence of solutions to fixed points of separately lower and upper semicontinuous (lower and lower, upper and upper) mappings.These generalize some well-known fixed point theorems obtained by previous authors as Browder and Ky Fan, Wu, et al., etc.  相似文献   

8.
An embedded pair of exponentially fitted explicit Runge–Kutta (RK) methods for the numerical integration of IVPs with oscillatory solutions is derived. This pair is based on the exponentially fitted explicit RK method constructed in Vanden Berghe et al., and we confirm that the methods which constitute the pair have algebraic order 4 and 3. Some numerical experiments show the efficiency of our pair when it is compared with the variable step code proposed by Vanden Berghe et al. (J. Comput. Appl. Math. 125 (2000) 107).  相似文献   

9.
This paper is the three dimensional extension of the two dimensional work in Nakao et al. (Reliable Comput 9(5):359–372, 2003) and Watanabe et al. (J Math Fluid Mech 6:1–20, 2004) on a computer assisted proof of the existence of nontrivial steady state solutions for Rayleigh–Bénard convection based on the fixed point theorem using a Newton like operator. The differences are emerging of complicated types of bifurcation, direct attack on the problem without stream functions, and increased complexity of numerical computation. The last one makes it hard to proceed the verification of solutions corresponding to the points on bifurcation diagram for three dimensional case. Actually, this work should be the first result for the three dimensional Navier–Stokes problems which seems to be very difficult to solve by theoretical approaches.  相似文献   

10.
研究了一类非线性生化系统的定性行为,给出了该系统极限环的不存在性、存在性、惟一性和稳定性的充分条件,补充和完善了戴林勋(1999)的结论。  相似文献   

11.
We prove the existence and uniqueness of solutions to Reflected Backward Doubly Stochastic Differential Equations (RBDSDEs) with one continuous barrier and uniformly Lipschitz coefficients. The existence of a maximal and a minimal solution for RBDSDEs with continuous generator is also established. To cite this article: K. Bahlali et al., C. R. Acad. Sci. Paris, Ser. I 347 (2009).  相似文献   

12.
Min et al. [1] (J. Min, Y.W. Zhou, J. Zhao, An inventory model for deteriorating items under stock-dependent demand and two-level trade credit, Appl. Math. Model. 34 (2010) 3273–3285.) develop an inventory model for deteriorating items under stock-dependent demand and two-level trade credit. They provide the necessary and sufficient conditions of the existence and uniqueness of the optimal solutions that could maximize the retailer’s average profit per unit time. Basically, their paper is correct and interesting. Recently, several researchers have been showing a huge interest in developing simple and easy to implement solution procedures in management science. Therefore this paper indicates that Min et al.’s solution procedure can be further improved and simplified. So, the main purpose of this paper is to present simple and easy to understand solution procedures to locate the optimal solutions of an inventory model that considers deteriorating items under stock-dependent demand and two-level trade credit.  相似文献   

13.
引进了(Φ,Δ)-型概率收缩偶的概念,它简化并减弱了张石生给出的概率收缩偶的定义。在N.A.Menger PN-空间中研究了具有这类概率收缩偶的非线性算子方程组的解的存在性与唯一性问题。改进并推广了M.Altman,A.C.Lee,W.J.Padgett,张石生等人的相应结果。  相似文献   

14.
The existence of at least one mass-conserving solution for continuous coagulation-fragmentation equation has been established by Escobedo et?al. (J Differ Equ 195:143?C174, 2003) for a large class of coagulation kernels under strong binary fragmentation. In this work, uniqueness of mass-conserving solutions is demonstrated with some additional restrictions on the fragmentation kernels.  相似文献   

15.
For random variables and random weights satisfying Marcinkiewicz-Zygmund and Rosenthal type moment inequalities, we establish complete convergence results for randomly weighted sums of the random variables. Our results generalize those of(Thanh et al. SIAM J. Control Optim., 49,106–124(2011), Han and Xiang J. Ineq. Appl., 2016, 313(2016), Li et al. J. Ineq. Appl., 2017, 182(2017), and Wang et al. Statistics, 52, 503–518(2018).)  相似文献   

16.
The global existence of solutions to a damped MHD system in Besov spaces is obtained. This research is motivated by the open question [Wu et al., J. Nonlinear Sci. 25 (2015), 157–192, Remark 5.1] on the possibility of extension to the existence of global small solutions from a potential Banach space to a Besov space. The present result positively confirms the open question. What is more, the initial data are not required to be uniformly small.  相似文献   

17.
In this paper, a multivalued variational inequality problem on uniformly prox-regular set is studied. The existence theorems for such aforementioned problem are presented and, consequently, some algorithms for finding those solutions are also constructed. The results in this paper can be viewed as an improvement of the significant result that presented in Bounkhel et al. (J Inequal Pure Appl Math 4(1), 2003, Article 14).  相似文献   

18.
In a recent paper by Xie et al. [Xie, J., Zhou, D., Wei, J.C., Zhao, X., 2010. Price discount based on early order commitment in a single manufacturer-multiple retailer supply chain. European Journal of Operational Research 200, 368-376], the authors have studied the early order commitment (EOC) strategy for a decentralized, two-level supply chain consisting of a single manufacturer and multiple retailers. They fail to provide an algorithm to determine the optimal EOC periods to minimize the total supply chain cost. This note proposes a polynomial-time algorithm to find the optimal solutions, and provides a new set of sufficient conditions under which the wholesale price discount scheme coordinates the whole supply chain.  相似文献   

19.
In this paper, we study the existence of martingale solutions of stochastic 3D Navier-Stokes equations with jump, and following Flandoli and Romito (2008) [7] and Goldys et al. (2009) [8], we prove the existence of Markov selections for the martingale solutions.  相似文献   

20.
Motivated by the results of J.Y.Chemin in "J.Anal.Math.,77,1999,27-50" and G.Furioli et al in "Revista Mat.Iberoamer.,16,2002,605-667",the author considers further regularities of the mild solutions to Navier-Stokes equation with initial data u0∈Ld(Rd).In particular,it is proved that if u∈C([0,T*); Ld(Rd)) is a mild solution of (NSv),then u(t,x) -evt△u0∈(L)∞ ((0,T); (B)1/d/2,∞)∩(L)1((0,T);(B)3/d/2,∞) for any T<T*.  相似文献   

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