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Shanghai, China

Tan Z.,Soochow University of China | Tan Z.,Zunyi Normal College | Wang Y.,Soochow University of China
Extremes | Year: 2012

Let X 1,X 2,... be a sequence of independent and identically distributed random variables and M n = max {X 1,X 2,..., X n}. Suppose that some of the random variables X 1,X 2,..., X n can be observed and denote by M̃ n the maximum of the observed random variables from the set {X 1,X 2,..., X n}. The limiting distribution of random vector M n-M̃ n, M̃ n) is derived. The result is also extended to the case of stationary Gaussian sequences. In the end, the almost sure limit theorem on M n-M̃ n for a sequence of independent and identically distributed random variables is proved. © 2011 Springer Science+Business Media, LLC. Source


Yang M.,Zunyi Normal College
Advances in Information Sciences and Service Sciences | Year: 2012

The Session Initiation Protocol (SIP) is one of the leading protocols for multimedia control over the Internet. Petri nets (PNs) are a popular model for specification and verification of protocols. In this paper, on the basis of the process of Session Initiation Protocol's service, Petri net model of SIP was established. We use Petri Nets to model and analyze SIP, in terms of properties of Petri net and the analysis of reachability tree, the protocol was proved to be reliable. Source


Liu Y.-M.,Zunyi Normal College
Xitong Fangzhen Xuebao / Journal of System Simulation | Year: 2011

In order to solve constraint optimization problems, an improved particle swarm optimizer was proposed for solving constrained optimization problem (ICPSO for short), which did not introduce penalty parameters to deal with constraints, but deal with constraints in terms of objective and the degree of the violation. In the process of search, the ICPSO algorithm searched the solution space by three different crossover methods based on population feasibility to crossover the best previous position of each particle (pbest), and the mutation was used to generate the new best performing particle (gbest) for leading the swarm flight. Finally, a hybrid particle velocity updating strategy was introduced to improve the probability of flying to the optimal solution. The ICPSO algorithm was tested on six well-known constrained optimization problems, and the experiment result shows the effectiveness and feasibility of the method. Source


Yan-min L.,Zunyi Normal College
Advances in Information Sciences and Service Sciences | Year: 2011

Multi-Objective Particle Swarm Optimizers (MOPSOs) easily converge to a false Pareto front (i.e., the equivalent of a local optimum in single objective optimization), and converge slowly when applied to solve Multi-objective optimization problems (MOPs). In this paper, we proposed a hybrid algorithm of MOPSO with dynamic neighborhood and evolutionary programming (denoted as DEPMOPSO) for solving MOPs. In DEPMOPSO, the neighborhood of each particle is dynamically constructed, and the velocity of each particle is adjusted by all particles in its neighborhood including itself, the best performing particle in the swarm and the elite group that is evolved using evolutionary programming. Moreover, the external archive is employed to store the nondominated solutions and ε-dominance based archive strategy is applied to update non-dominated solution. Simulation results show that DEPMOPSO is able to find a much better spread of solutions and has faster convergence to true Pareto-optimal front compared with five state-of-the-art MOPSOs. Source


Li X.,CAS Fujian Institute of Research on the Structure of Matter | Li X.,Zunyi Normal College | Huang Y.,CAS Fujian Institute of Research on the Structure of Matter | Cao R.,CAS Fujian Institute of Research on the Structure of Matter
Crystal Growth and Design | Year: 2012

Hydrothermal reactions of isonicotinic acid (Hina) and hemimellitic acid (H 3hma) with lanthanide oxides and copper halides yielded 10 three-dimensional (3D) pillared-layer 3d-4f heterometallic coordination polymers (HCPs) with three structural types. They are formulated as [Ln 2Cu 2(μ 2-X)(hma)(ina) 4(H 2O) 2] n•2nH 2O [Ln = La, X = Cl (I-A), Ln = La, X = Br (I-B), Ln = La, X = I (I-C), Ln = Nd, X = Cl (I-D), Ln = Nd, X = Br (I-E)], [Ln 3Cu 4.5I 3.5(μ 3-OH)(hma)(ina) 6(H 2O)] n•nH 2O [Ln = Pr (II-A), Nd(II-B)], and [LnCu 0.5(hma)(ina)(H 2O)] n•nH 2O [Ln = La (III-A), Ce (III-B), Pr (III-C)]. All the HCPs are characterized by single-crystal X-ray diffractions. In type I structures, Ln-organic layers are pillared by halide-bridged dinuclear [Cu 2(μ 2-Cl)(ina) 4] units through Ln-O bonds. In type II structures, Ln-organic layers are pillared by two different kinds of monovalent Cu-based building units, namely, halide-free [Cu(ina) 2] and halide-containing [Cu 8(μ 3-I) 6(μ 4-I)(ina) 10] n. In type III structures, undulate heterometallic Cu(II)-Ln(III) layers are pillared by organic ina ligands via Ln-O and Cu-N bonds. The solid-state photoluminescent properties of I-D and II-B were also investigated at room temperature. © 2012 American Chemical Society. Source

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