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1.
Let F=C(x1,x2,…,xe,xe+1,…,xm), where x1, x2,… , xe are differential variables, and xe+1,…,xm are shift variables. We show that a hyperexponential function, which is algebraic over F,is of form g(x1, x2, …,xm)q(x1,x2,…,xe)^1/lwe+1^xe+1…wm^xm, where g∈ F, q ∈ C(x1,x2,…,xe),t∈Z^+ and we+1,…,wm are roots of unity. Furthermore,we present an algorithm for determining whether a hyperexponential function is algebraic over F.  相似文献   

2.
We study two-weight norm inequality for imaginary powers of a Laplace operator in R^n, n ≥ 1, especially from weighted Lebesgue space Lv^p(R^n) to weighted Lebesgue space Lμ^p(R^n), where 1 〈 p 〈 ∞. We prove that the two-weighted norm inequality holds whenever for some t 〉 1, (μ^t, v^t) ∈ Ap, or if (μ, v) ∈Ap, where μ and v^-1/(p-1) satisfy the growth condition and reverse doubling property.  相似文献   

3.
Let be the set of trees on 2k+1 vertices with nearly perfect matchings, and let be the set of trees on 2k + 2 vertices with perfect matchings. The largest Laplacian spectral radii of trees in and and the corresponding trees were given by Guo (2003). In this paper, the authors determine the second to the sixth largest Laplacian spectral radii among all trees in and give the corresponding trees. This research is supported by the National Natural Science Foundation of China under Grant No. 10331020.  相似文献   

4.
In generalized linear models with fixed design, under the assumption λ↑_n→∞ and other regularity conditions, the asymptotic normality of maximum quasi-likelihood estimator ^↑βn, which is the root of the quasi-likelihood equation with natural link function ∑i=1^n Xi(yi -μ(Xi′β)) = 0, is obtained, where λ↑_n denotes the minimum eigenvalue of ∑i=1^nXiXi′, Xi are bounded p × q regressors, and yi are q × 1 responses.  相似文献   

5.
The author concerned the reliability evaluation as well as queueing analysis of M1, M2/G1, G2/1 retrial queues with two different types of primary customers arriving according to independent Poisson flows. In the case of blocking, the first type of customers can be queued whereas the second type of customers must leave the service area but return after some random period of time to try their luck again. The author assumes that the server is unreliable and it has a service-type dependent, exponentially distributed life time as well as a service-type dependent, generally distributed repair time. The necessary and sufficient condition for the system to be stable is investigated. Using a supplementary variable method, the author obtains a steady-state solution for queueing measures, and the transient as well as the steady-state solutions for reliability measures of interest.  相似文献   

6.
In this paper, we investigate the growth of meromorphic solutions of higher order linear differential equation f^(k) +Ak-1 (z)e^Pk-1^(z) f^(k-1) +…+A1 (z)e^P1(z) f′ +Ao(z)e^Po(z) f = 0 (k ≤ 2), where Pj(z) (j = 0, 1,..., k - 1) are nonconstant polynomials such that deg Pj = n (j = 0, 1,..., k - 1) and Aj(z)(≠ 0) (j = 0, 1,..., k - 1) are meromorphic functions with order p(Aj) 〈 n (j = 0, 1,..., k - 1).  相似文献   

7.
This paper studies variational discretization for the optimal control problem governed by parabolic equations with control constraints.First of all,the authors derive a priori error estimates where |||u-U(h|||L∞(J;L2(Ω))=O(h2+k).It is much better than a priori error estimates of standard finite element and backward Euler method where |||μ-Uh|||(L∞(J;L2(Ω))=O(h+ k).Secondly,the authors obtain a posteriori error estimates of residual type.Finally,the authors present some numerical algorithms for the optimal control problem and do some numerical experiments to illustrate their theoretical results.  相似文献   

8.
Given a real-valued separable M-type 2 Banach space X with the p-th power of the norm of C2-class, the almost sure asymptotic upper bounds of the solutions of the Ornstein-Uhlenbeck Processes described by the following equations {dz(t)=A(t,z(t))dt+σ(t,z(t))dW(t),z(0)=z0∈X,are investigated. This study generalizes the corresponding well-known finite dimensional results of Lapeyre (1989) and Mao (1992).  相似文献   

9.
It has been observed in laboratory experiments that when nonlinear dispersive waves are forced periodically from one end of undisturbed stretch of the medium of propagation, the signal eventually becomes temporally periodic at each spatial point. The observation has been confirmed mathematically in the context of the damped Korteweg-de Vries (KdV) equation and the damped Benjamin-Bona-Mahony (BBM) equation. In this paper we intend to show the same results hold for the pure KdV equation (without the damping terms) posed on a finite domain. Consideration is given to the initial-boundary-value problem {ut+ux+uux+uxxx=0, u(x,0)=φ(x), 0〈x〈1, t〉0,u(0,t)=h(t), u(1,t) = 0, ux(1,t) = 0, t〉0.It is shown that if the boundary forcing h is periodic with small ampitude, then the small amplitude solution u of (*) becomes eventually time-periodic. Viewing (*) (without the initial condition) as an infinite-dimensional dynamical system in the Hilbert space L^2(0, 1), we also demonstrate that for a given periodic boundary forcing with small amplitude, the system (*) admits a (locally) unique limit cycle, or forced oscillation, which is locally exponentially stable. A list of open problems are included for the interested readers to conduct further investigations.  相似文献   

10.
This paper presents an algorithm that tests whether a given degree-bounded digraph is k-edge-connected or ɛ-far from k-edge-connectivity. This is the first testing algorithm for k-edgeconnectivity of digraphs whose running time is independent of the number of vertices and edges. A digraph of n vertices with degree bound d is ɛ-far from k-edge-connectivity if at least ɛdn edges have to be added or deleted to make the digraph k-edge-connected, preserving the degree bound. Given a constant error parameter ɛ and a degree bound d, our algorithm always accepts all k-edge-connected digraphs and rejects all digraphs that is ɛ-far from k-edge-connectivity with probability at least 2/3. It runs in $ O\left( {d\left( {\frac{c} {{\varepsilon d}}} \right)^k log\frac{1} {{\varepsilon d}}O} \right) $ O\left( {d\left( {\frac{c} {{\varepsilon d}}} \right)^k log\frac{1} {{\varepsilon d}}O} \right) (c > 1 is a constant) time when input digraphs are restricted to be (k-1)-edge connected and runs in $ O\left( {d\left( {\frac{{ck}} {{\varepsilon d}}} \right)^k log\frac{k} {{\varepsilon d}}O} \right) $ O\left( {d\left( {\frac{{ck}} {{\varepsilon d}}} \right)^k log\frac{k} {{\varepsilon d}}O} \right) (c > 1 is a constant) time for general digraphs.  相似文献   

11.
Wireless sensor networks promise a new paradigm for gathering data via collaboration among sensors spreading over a large geometrical region. Many applications impose delay requirements for data gathering and ask for time-efficient schedules for aggregating sensed data and sending to the data sink. In this paper, the authors study the minimum data aggregation time problem under collision-free transmission model. In each time round, data sent by a sensor reaches all sensors within its transmission range, but a sensor can receive data only when it is the only data that reaches the sensor. The goal is to find the method that schedules data transmission and aggregation at sensors so that the time for all requested data to be sent to the data sink is minimal. The authors propose a 7△/log2|s|+c, new approximation algorithm for this NP-hard problem with guaranteed performance ratio which significantly reduces the current best ratio of △- 1, where S is the set of sensors containing source data, A is the maximal number of sensors within the transmission range of any sensor, and e is a constant. The authors also conduct extensive simulation, the obtained results justify the improvement of proposed algorithm over the existing one.  相似文献   

12.
We propose a new family of interconnection networks (WGn^m) with regular degree three. When the generator set is chosen properly, they are isomorphic to Cayley graphs on the wreath product Zm ~ Sn. In the case of m ≥ 3 and n ≥3, we investigate their different algebraic properties and give a routing algorithm with the diameter upper bounded by [m/2](3n^2- 8n + 4) - 2n + 1. The connectivity and the optimal fault tolerance of the proposed networks are also derived. In conclusion, we present comparisons of some familiar networks with constant degree 3.  相似文献   

13.
On-Line Scheduling with Rejection on Identical Parallel Machines   总被引:1,自引:0,他引:1  
In this paper, we consider the on-line scheduling of unit time jobs with rejection on rn identical parallel machines. The objective is to minimize the total completion time of the accepted jobs plus the total penalty of the rejected jobs. We give an on-line algorithm for the problem with competitive ratio 1/2 (2 +√3) ≈ 1.86602.  相似文献   

14.
This paper considers the Rosenau equation with a moving control?t u + ?_t?_x~4 u + ?_xu + u?x u = a(x + ct)h(x, t), c = 0, x ∈ T = R/(2πZ), t 0.The authors prove that the Rosenau equation with a moving control is locally exact controllable in Hs(T) with s ≥ 0 and globally exponential stable in H~s(T) with s ≥ 2. The two results nontrivially extend the work of(Rosier L and Zhang B Y, 2013) from the BBM equation to the Rosenau equation.  相似文献   

15.
On the Convergence of a New Hybrid Projection Algorithm   总被引:1,自引:1,他引:0  
For unconstrained optimization, a new hybrid projection algorithm is presented m the paper. This algorithm has some attractive convergence properties. Convergence theory can be obtained under the condition that Δ↓f(x) is uniformly continuous. If Δ↓f(x) is continuously differentiable pseudo-convex, the whole sequence of iterates converges to a solution of the problem without any other assumptions. Furthermore, under appropriate conditions one shows that the sequence of iterates has a cluster-point if and only if Ω* ≠ θ. Numerical examples are given at the end of this paper.  相似文献   

16.
ON (∈, ∈ ∨q)-FUZZY FILTERS OF BL-ALGEBRAS   总被引:1,自引:0,他引:1  
The authors introduce the notions of (∈, ∈ ∨q)-fuzzy Boolean (implicative, positive implicative, and fantastic) filters in BL-algebras, present some characterizations on these generalized fuzzy filters, and describe the relations among these generalized fuzzy filters. It is proved that an (∈, ∈ ∨q)fuzzy filter in a BL-algebra is Boolean (implicative) if and only if it is both positive implicative and fantastic.  相似文献   

17.
This paper introduces a Gray map from(Fp + uFpn to Fp2n,and describes the relationship between codes over Fp + vFp and their Gray images.The authors prove that every cyclic code of arbitrary length n over Fp + vFp is principal,and determine its generator polynomial as well as the number of cyclic codes.Moreover,the authors obtain many best-known p-ary quasic-cyclic codes in terms of their parameters via the Gray map.  相似文献   

18.
This paper is devoted to the study of semi-bent functions with several parameters flexible on the finite field F2n.Boolean functions defined on F2n of the form f(r)ab(x) =Trn1(axr(2m-1))+Tr41(bx(2n-1)/5) and the form g(rs)abcd(x)=Trn1(axr(2m-1))+Tr41(bx(2n-1)/5)+Trn1(cx(2m-1)1/2+1)+Trn1(dx(2m-1)s+1) where n = 2m,m = 2(mod 4),a,c ∈ F2n,and b ∈ F(16),d ∈ F2,are investigated in constructing new classes of semi-bent functions.Some characteristic sums such as Kloosterman sums and Weil sums are employed to determine whether the above functions are semi-bent or not.  相似文献   

19.
This paper deduces the structure of LCD negacyclic codes over the finite field Fq, where q is an odd prime power. Based on the study of q-cyclotomic cosets modulo 2 n, the authors obtain the parameters of LCD negacyclic codes of lengths n =(q+1)/2,(q~m-1)/2(q-1)and q~(t·2~τ)-1/2(q~t +1), respectively. And many optimal codes are given. Moreover, the authors research two special classes of MDS LCD negacyclic codes of length n |(q-1)/2 and n |(q+1)2, respectively.  相似文献   

20.
<正> Let Q_n and B_n denote a quasi-polyomino chain with n squares and a quasi-hexagonalchain with n hexagons,respectively.In this paper,the authors establish a relation between the Wienernumbers of Q_n and B_n:W(Q_n)=1/4[W(B_n)-8/3n~3+(14)/3n+3].And the extremal quasi-polyominochains with respect to the Wiener number are determined.Furthermore,several classes of polyominochains with large Wiener numbers are ordered.  相似文献   

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