We present a convergence analysis of a stochastic method for numerical modeling of complex fluids using Brownian configuration fields (BCF) for shear flows. The analysis takes into account the special structure of the stochastic partial differential equations for shear flows. We establish the optimal rate of convergence. We also analyze the nature of the error by providing its leading order asymptotics.
We present a convergence analysis of a stochastic method for numerical modeling of complex fluids using Brownian configuration fields (BCF) for shear flows. The analysis takes into account the special structure of the stochastic partial differential equations for shear flows. We establish the optimal rate of convergence. We also analyze the nature of the error by providing its leading order asymptotics.
In this paper, we apply the backward equations of Markov skeleton processes to queueing systems. The transient distribution of the waiting time of a G1/G/1 queueing system, the transient distribution of the length of a G1/G/N queueing system and the transient distribution of the length of queueing networks are obtained.
In this paper, we apply the backward equations of Markov skeleton processes to queueing systems. The transient distribution of the waiting time of a G1/G/1 queueing system, the transient distribution of the length of a G1/G/N queueing system and the transient distribution of the length of queueing networks are obtained.
The Kurzweil-Henstock integral formalism is applied to establish the existence of solutions to the linear integral equations of Volterra-type x(t)=~*∫_([a,t]) α(s)x(s)ds=f(t), t∈[a,b], where the functions are Banach-space valued. Special theorems on existence of solutions concerning the Lebesgue integral setting are obtained. These sharpen earlier results.
The Kurzweil-Henstock integral formalism is applied to establish the existence of solutions to the linear integral equations of Volterra-type x(t)=~*∫_([a,t]) α(s)x(s)ds=f(t), t∈[a,b], where the functions are Banach-space valued. Special theorems on existence of solutions concerning the Lebesgue integral setting are obtained. These sharpen earlier results.
Generalized Steiner triple systems, (GS(2,3,n,g), are equivalent to maximum constant weight codes over an alphabet of size g+1 with distance 3 and weight 3 in which each codeword has length n. The necessary conditions for the existence of a GS(2,3,n,g) are (nm1)gL0 (mod 2), n(nm1)g~2≡0 (mod 6), and n≥g+2. These necessary conditions are shown to be sufficient by several authors for 2≤g≤11. In this paper, three new results are obtained. First, it is shown that for any given g, gL0 (mod 6) and g≥12, if there exists a GS(2,3,n,g) for all n, g+2≤n≤7g+13, then the necessary conditions are also sufficient. Next, it is also shown that for any given g, gL3 (mod 6) and g≥15, if there exists a GS(2,3,n,g) for all n, nL1 (mod 2) and g+2≤n≤7g+6, then the necessary conditions are also sufficient. Finally, as an application, it is proved that the necessary conditions for the existence of a GS(2,3,n,g) are also sufficient for g=12,15.
Generalized Steiner triple systems, (GS(2,3,n,g), are equivalent to maximum constant weight codes over an alphabet of size g+1 with distance 3 and weight 3 in which each codeword has length n. The necessary conditions for the existence of a GS(2,3,n,g) are (nm1)gL0 (mod 2), n(nm1)g~2≡0 (mod 6), and n≥g+2. These necessary conditions are shown to be sufficient by several authors for 2≤g≤11. In this paper, three new results are obtained. First, it is shown that for any given g, gL0 (mod 6) and g≥12, if there exists a GS(2,3,n,g) for all n, g+2≤n≤7g+13, then the necessary conditions are also sufficient. Next, it is also shown that for any given g, gL3 (mod 6) and g≥15, if there exists a GS(2,3,n,g) for all n, nL1 (mod 2) and g+2≤n≤7g+6, then the necessary conditions are also sufficient. Finally, as an application, it is proved that the necessary conditions for the existence of a GS(2,3,n,g) are also sufficient for g=12,15.
In this paper we shall consider the nonresonance Dirichlet boundary value problem {-x'' + ρp(t)x = λf(t,x), t∈(0, 1), x(0)=x(1)=0, where λ>0 is a parameter, ρ>0 is a constant. Intervals of 5 are determined to ensure the existence of a nonnegative solution of the boundary value problem. For λ=1, we shall also offer criteria for the existence of eigenfunctions. The main results include and improve on those of [2,4,6,8].
In this paper we shall consider the nonresonance Dirichlet boundary value problem {-x'' + ρp(t)x = λf(t,x), t∈(0, 1), x(0)=x(1)=0, where λ>0 is a parameter, ρ>0 is a constant. Intervals of 5 are determined to ensure the existence of a nonnegative solution of the boundary value problem. For λ=1, we shall also offer criteria for the existence of eigenfunctions. The main results include and improve on those of [2,4,6,8].
In this paper we consider the Burger-Ginzburg-Landau equations, and prove the existence of the global attractor in H_0~n*H~n, A_n≥0, with finite Hausdorff and fractal dimensions
In this paper we consider the Burger-Ginzburg-Landau equations, and prove the existence of the global attractor in H_0~n*H~n, A_n≥0, with finite Hausdorff and fractal dimensions
In this paper, we consider the boundary stabilization of the wave equation with variable coefficients by Riemannian geometry method subject to a different geometric condition which is motivated by the geometric multiplier identities. Several (multiplier) identities (inequalities) which have been built for constant wave equation by Kormornik and Zuazua~([2]) are generalized to the variable coefficient case by some computational techniques in Riemannian geometry, so that the precise estimates on the exponential decay rate are derived from those inequalities. Also, the exponential decay for the solutions of semilinear wave equation with variable coefficients is obtained under natural growth and sign assumptions on the nonlinearity. Our method is rather general and can be adapted to other evolution systems with variable coefficients (e.g. elasticity plates) as well.
In this paper, we consider the boundary stabilization of the wave equation with variable coefficients by Riemannian geometry method subject to a different geometric condition which is motivated by the geometric multiplier identities. Several (multiplier) identities (inequalities) which have been built for constant wave equation by Kormornik and Zuazua~([2]) are generalized to the variable coefficient case by some computational techniques in Riemannian geometry, so that the precise estimates on the exponential decay rate are derived from those inequalities. Also, the exponential decay for the solutions of semilinear wave equation with variable coefficients is obtained under natural growth and sign assumptions on the nonlinearity. Our method is rather general and can be adapted to other evolution systems with variable coefficients (e.g. elasticity plates) as well.
In this paper, we study the existence of nontrivial solutions for the following Dirichlet problem for the p-Laplacian (p>1): {-Δ_pu≡-div |▽u|~(p-2)▽u)=f(x,u), x∈Ω, u=0, x∈partial deriv Ω, where Ω is a bounded domain in R~N (N≥1) and f(x, u) is quasi-asymptotically linear with respect to |u|~(p-2) u at infinity. Recently it was proved that the above problem has a positive solution under the condition that f (x,s)/s~(p-1) is nondecreasing with respect to s for all x∈Ω and some others. In this paper, by improving the methods in the literature, we prove that the functional corresponding to the above problem still satisfies a weakened version of (P.S.) condition even if f(x,s)/s~(p-1) isn't a nondecreasing function with respect to s, and then the above problem has a nontrivial weak solution by Mountain Pass Theorem.
In this paper, we study the existence of nontrivial solutions for the following Dirichlet problem for the p-Laplacian (p>1): {-Δ_pu≡-div |▽u|~(p-2)▽u)=f(x,u), x∈Ω, u=0, x∈partial deriv Ω, where Ω is a bounded domain in R~N (N≥1) and f(x, u) is quasi-asymptotically linear with respect to |u|~(p-2) u at infinity. Recently it was proved that the above problem has a positive solution under the condition that f (x,s)/s~(p-1) is nondecreasing with respect to s for all x∈Ω and some others. In this paper, by improving the methods in the literature, we prove that the functional corresponding to the above problem still satisfies a weakened version of (P.S.) condition even if f(x,s)/s~(p-1) isn't a nondecreasing function with respect to s, and then the above problem has a nontrivial weak solution by Mountain Pass Theorem.
A disease transmission model of SIS type with stage structure and a delay is formulated. Stability of the disease free equilibrium, and existence, uniqueness, and stability of an endemic equilibrium, are investigated for the model. The stability results are stated in terms of a key threshold parameter. The effects of stage structure and time delay on dynamical behavior of the infectious disease are analyzed. It is shown that stage structure has no effect on the epidemic model and Hopf bifurcation can occur as the time delay increases.
A disease transmission model of SIS type with stage structure and a delay is formulated. Stability of the disease free equilibrium, and existence, uniqueness, and stability of an endemic equilibrium, are investigated for the model. The stability results are stated in terms of a key threshold parameter. The effects of stage structure and time delay on dynamical behavior of the infectious disease are analyzed. It is shown that stage structure has no effect on the epidemic model and Hopf bifurcation can occur as the time delay increases.
The comparison theorem for generalized backward stochastic differential equations is discussed. Some topics related to equations of this type are also investigated.
The comparison theorem for generalized backward stochastic differential equations is discussed. Some topics related to equations of this type are also investigated.
In this paper, we discuss a simplified model of mitosis in frog eggs proposed by M. T. Borisuk and J. J. Tyson in [1]. By using rigorous qualitative analysis, we prove the existence of the periodic solutions on a large scale and present the space region of the periodic solutions and the parameter region coresponding to the periodic solution. We also present the space region and the parameter region where there are no periodic solutions. The results are in accordance with the numerical results in [1] up to the qualitative property
In this paper, we discuss a simplified model of mitosis in frog eggs proposed by M. T. Borisuk and J. J. Tyson in [1]. By using rigorous qualitative analysis, we prove the existence of the periodic solutions on a large scale and present the space region of the periodic solutions and the parameter region coresponding to the periodic solution. We also present the space region and the parameter region where there are no periodic solutions. The results are in accordance with the numerical results in [1] up to the qualitative property
This paper is concerned with the error behavior of one-leg methods applied to some classes of one-parameter multiple stiff singularity perturbed problems with delays. We derive the global error estimates of A-stable-one-leg methods with linear interpolation procedure.
This paper is concerned with the error behavior of one-leg methods applied to some classes of one-parameter multiple stiff singularity perturbed problems with delays. We derive the global error estimates of A-stable-one-leg methods with linear interpolation procedure.
Data collected on the surface of the earth often has spatial interaction. In this paper, a non-isotropic mixing spatial data process is introduced, and under such a spatial structure a nonparametric kernel method is suggested to estimate a spatial conditional regression. Under mild regularities, sufficient conditions are derived to ensure the weak consistency as well as the convergence rates for the kernel estimator. Of interest are the following: (1) All the conditions imposed on the mixing coefficient and the bandwidth are simple; (2) Differently from the time series setting, the bandwidth is found to be dependent on the dimension of the site in space as well; (3) For weak consistency, the mixing coefficient is allowed to be unsummable and the tendency of sample size to infinity may be in different manners along different direction in space; (4) However, to have an optimal convergence rate, faster decreasing rates of mixing coefficient and the tendency of sample size to infinity along each direction are required.
Data collected on the surface of the earth often has spatial interaction. In this paper, a non-isotropic mixing spatial data process is introduced, and under such a spatial structure a nonparametric kernel method is suggested to estimate a spatial conditional regression. Under mild regularities, sufficient conditions are derived to ensure the weak consistency as well as the convergence rates for the kernel estimator. Of interest are the following: (1) All the conditions imposed on the mixing coefficient and the bandwidth are simple; (2) Differently from the time series setting, the bandwidth is found to be dependent on the dimension of the site in space as well; (3) For weak consistency, the mixing coefficient is allowed to be unsummable and the tendency of sample size to infinity may be in different manners along different direction in space; (4) However, to have an optimal convergence rate, faster decreasing rates of mixing coefficient and the tendency of sample size to infinity along each direction are required.
In this paper, by using the method of algebraic analysis, the results in our previous work are generalized. These results are of importance in the qualitative theory of polynomial autonomous systems.
In this paper, by using the method of algebraic analysis, the results in our previous work are generalized. These results are of importance in the qualitative theory of polynomial autonomous systems.
The classes of the multivariate functions with bounded moduli on R~d and T~d are given and their average σ-widths and non-linear n-widths are discussed. The weak asymptotic behaviors are established for the corresponding quantities.
The classes of the multivariate functions with bounded moduli on R~d and T~d are given and their average σ-widths and non-linear n-widths are discussed. The weak asymptotic behaviors are established for the corresponding quantities.
Embrechts and Veraverbeke~[2] investigated the renewal risk model and gave a tail equivalence relationship of the ruin probabilities ψ(x) under the assumption that the claim size is heavy-tailed, which is regarded as a classical result in the context of extremal value theory. In this note we extend this result to the delayed renewal risk model.
Embrechts and Veraverbeke~[2] investigated the renewal risk model and gave a tail equivalence relationship of the ruin probabilities ψ(x) under the assumption that the claim size is heavy-tailed, which is regarded as a classical result in the context of extremal value theory. In this note we extend this result to the delayed renewal risk model.
In this paper we prove that if T is a regular n-partite tournament with n≥6, then each arc of T lies on a k-cycle for k=4,5,...,n. Our result generalizes theorems due to Alspach[1] and Guo~[3] respectively.
In this paper we prove that if T is a regular n-partite tournament with n≥6, then each arc of T lies on a k-cycle for k=4,5,...,n. Our result generalizes theorems due to Alspach[1] and Guo~[3] respectively.
In this paper, we discuss the classical risk process with stochastic return on investment. We prove some properties of the ruin probability, the supremum distribution before ruin and the surplus distribution at the time of ruin and derive the integro-differential equations satisfied by these distributions respectively.
In this paper, we discuss the classical risk process with stochastic return on investment. We prove some properties of the ruin probability, the supremum distribution before ruin and the surplus distribution at the time of ruin and derive the integro-differential equations satisfied by these distributions respectively.
We propose the variational description of generating function approach of first kind for Hamiltonian ODEs, and extend the approach to the semi-linear wave equations. In this way, we can construct any finite order accuracy scheme, and show that the resulting numerical scheme is multisymplectic. At last, we present some numerical experiments by using derived new scheme.
We propose the variational description of generating function approach of first kind for Hamiltonian ODEs, and extend the approach to the semi-linear wave equations. In this way, we can construct any finite order accuracy scheme, and show that the resulting numerical scheme is multisymplectic. At last, we present some numerical experiments by using derived new scheme.