查看更多>>摘要：Let Fq be the finite field,q=pk,with p being a prime and k being a positive integer.Let F*q be the multiplicative group of Fq,that is F*q=Fq\{0}.In this paper,by using the Jacobi sums and an analog of Hasse-Davenport theorem,an explicit formula for the number of solutions of cubic diagonal equation x31+x32+…+x3n=c over Fq is given,where c ∈ F*q and p ≡1(mod 3).This extends earlier results.
查看更多>>摘要：In this paper,a class of slow reaction-diffusion equations with nonlocal source and inner absorption terms are studied.By using the technique of improved differential inequality,the lower bounds of blow up time for the system under either homogeneous Dirichlet or nonhomogeneous Neumann boundary conditions are obtained.
查看更多>>摘要：Let A be a unital *-algebra with the unit Ⅰ and a nontrivial projection P∈A Suppose that A satisfies XAP=0 implies X=0 and XA(I-P)=0 implies X=0.In this paper,we prove that φ is a nonlinear A*B+B*A type derivation on A if and only if φ is an additive *-derivation.This is then applied to prime *-algebra,von Neumann algebras with no central summands of type Ⅰ1,factor von Neumann al-gebras and standard operator algebras.
查看更多>>摘要：In this paper,we investigate the presentation for little q-Schur algebra uk(3,5)at odd roots.The Poincaré-Birkhoff-Witt(PBW)basis of uk(3,5)is obtained through the basis of q-Schur algebra U(3,5).Then we present a new set for generators and relations for uk(3,5)by PBW basis.
查看更多>>摘要：In this paper,a-Browder's theorem and a-Weyl's theorem for bounded linear operators are studied by means of the property of the topological uniform descent.The sufficient and necessary conditions for a bounded linear operator defined on a Hilbert space holding a-Browder's theorem and a-Weyl's theorem are established.As a consequence of the main result,the new judgements of a-Browder's theo-rem and a-Weyl's theorem for operator function are discussed.
查看更多>>摘要：In this paper,our main aim is to investigate the strong convergence rate of the truncated Euler-Maruyama approximations for stochastic differential equations with superlinearly growing drift coefficients.When the diffusion coefficient is polynomially growing or linearly growing,the strong convergence rate of arbitrarily close to one half is established at a single time T or over a time interval[0,T],re-spectively.In both situations,the common one-sided Lipschitz and polynomial growth conditions for the drift coefficients are not required.Two examples are provided to illustrate the theory.
查看更多>>摘要：This paper concerns a discontinuous Galerkin(DG)method for a one-dimensional singularly perturbed problem which pos-sesses essential characteristic of second order convection-diffusion problem after some simple transformations.We derive an optimal con-vergence of the DG method for eight layer-adapted meshes in a general framework.The convergence rate is valid independent of the small parameter.Furthermore,we establish a sharper L2-error estimate if the true solution has a special regular component.Numerical experi-ments are also given.
查看更多>>摘要：Response and bifurcation of fractional Duffing oscillator under recycling noise and time-delayed feedback control are investi-gated.Firstly,based on the principle of the minimum mean square error and small time-delayed approximation and linearize the cubic stiff-ness term,the fractional derivative is equivalent to a linear combination of damping and restoring forces,and the original system is simpli-fied into an equivalent integer order system.Secondly,the Ito differential equations and one-dimensional Markov process are obtained ac-cording to stochastic averaging method,and the stochastic stability and stochastic bifurcation of the system are analyzed.Lastly,through joint probability density function diagram and the stationary probability density function diagram,the stochastic bifurcation behavior of system under the different time-delay,fractional order and noise intensity are discussed respectively,the validity of the theory and the oc-currence of bifurcation phenomenon are verified.
查看更多>>摘要：The double row layout problem(DRLP)is to assign facilities on two rows in parallel so that the total cost of material handling among facilities is minimized.Since it is vital to save cost and enhance productivity,the DRLP plays an important role in many application fields.Nevertheless,it is very hard to handle the DRLP because of its complex model.In this paper,we consider a new simplified model for the DRLP(SM-DRLP)and provide a mixed integer programming(MIP)formulation for it.The continuous decision variables of the DRLP are divided into two parts:start points of double rows and adjustable clearances between adjacent facilities.The former one is con-sidered in the new simplified model for the DRLP with the purpose of maintaining solution quality,while the latter one is not taken into ac-count with the purpose of reducing computational time.To evaluate its performance,our SM-DRLP is compared with the model of a gen-eral DRLP and the model of another simplified DRLP.The experimental results show the efficiency of our proposed model.
查看更多>>摘要：The pre-earthquake ionospheric anomalies in Wenchuan,China(21°-41°N,93°-113°E)are studied and analyzed using the sum-mer nighttime data from 2005 to 2008 measured by DEMETER(Detection of Electro-Magnetic Emission Transmitted from Earthquake Regions)satellite detectors ICE(Internet Communications Engine),IAP(In Application Programming),and ISL(Interior Switching Link).In this paper,we take the 12 May 2008 Wenchuan earthquake as an example,use the spatial gridding method to construct the background field over the epicenter,analyze the background characteristics of very low frequency(VLF)electric field components,low-energy particle parameters,and plasma parameters,and define the perturbation intensity index of each parameter before the earthquake to extract each pa-rameter anomaly in both space and time dimensions.The results show that the background values of some ionospheric parameters in the Wenchuan area are related to spatial distribution.Moreover,anomalous enhancement of low-frequency electric field power spectral den-sity,H+concentration,He+concentration and ion concentration with different intensities and anomalous weakening of ion temperature were extracted in the fifteen days before the Wenchuan earthquake.After filtering the data to exclude external interference,such as solar ac-tivity,this paper concludes that there is some connection between these anomalies and the Wenchuan earthquake.
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