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921.
Ablikim M  Bai JZ  Ban Y  Cai X  Chen HF  Chen HS  Chen HX  Chen JC  Chen J  Chen YB  Chi SP  Chu YP  Cui XZ  Dai YS  Deng ZY  Dong LY  Dong QF  Du SX  Du ZZ  Fang J  Fang SS  Fu CD  Gao CS  Gao YN  Gu SD  Gu YT  Guo YN  Guo YQ  Guo ZJ  Harris FA  He KL  He M  Heng YK  Hu HM  Hu T  Huang GS  Huang XP  Huang XT  Ji XB  Jiang XS  Jiao JB  Jin DP  Jin S  Jin Y  Lai YF  Li G  Li HB  Li HH  Li J  Li RY  Li SM  Li WD  Li WG  Li XL  Li XQ  Li YL  Liang YF  Liao HB  Liu CX  Liu F  Liu F  Liu HH  Liu HM  Liu J  Liu JB  Liu JP  Liu RG  Liu ZA  Lu F  Lu GR  Lu HJ  Lu JG 《Physical review letters》2006,97(14):142002
A broad peak is observed at low K+K- invariant mass in J/psi-->K+K-pi(0) decays found in a sample of 5.8x10(7) J/psi events collected with the BESII detector. The statistical significance of the broad resonance is much larger than 5sigma. A partial wave analysis shows that the J;{PC} of this structure is 1--. Its pole position is determined to be [1576(-55)(+49)(stat)-91+98(syst)] MeV/c(2)-i/2[818(-23)(+22)(stat)-133+64(syst)] MeV/c(2). These parameters are not compatible with any known meson resonances.  相似文献   
922.
Let (B t + f(t)) t∈[0,+∞) be a Brownian motion with polynomial drift f(t), where f(t) is a polynomial. Some Limit Results for Lower tail and large deviation probabilities estimates, and Level crossing probabilities estimates of (B t + f(t)) t∈[0,+∞) are given in this paper.  相似文献   
923.
Hopf bifurcation which produces oscillations is a very important phenomena in the theory and application of dynamical systems. Almost all works available about Hopf bifurcations are related to a non-degenerate focus or center. For the case of a degenerate focus or center, the study of the bifurcations becomes challenge. In this paper, we consider the bifurcation of limit cycles for a quartic near-Hamiltonian system by perturbing a nilpotent center. We take coefficients as parameters, then we can get six limit cycles.  相似文献   
924.
Additive maps derivable or Jordan derivable at zero point on nest algebras   总被引:1,自引:0,他引:1  
Let AlgN be a nest algebra associated with the nest N on a (real or complex) Banach space X. Assume that every NN is complemented whenever N-=N. Let δ:AlgN→AlgN be an additive map. It is shown that the following three conditions are equivalent: (1) δ is derivable at zero point, i.e., δ(AB)=δ(A)B+Aδ(B) whenever AB=0; (2) δ is Jordan derivable at zero point, i.e., δ(AB+BA)=δ(A)B+Aδ(B)+Bδ(A)+δ(B)A whenever AB+BA=0; (3) δ has the form δ(A)=τ(A)+cA for some additive derivation τ and some scalar c. It is also shown that δ is generalized derivable at zero point, i.e., δ(AB)=δ(A)B+Aδ(B)-Aδ(I)B whenever AB=0, if and only if δ is an additive generalized derivation. Finer characterizations of above maps are given for the case dimX=.  相似文献   
925.
A method for constructing solutions of the Hom-Yang–Baxter equations is presented. Thus, methods yields a so-called α-involutory solution of the Hom-Yang–Baxter equation for every monoidal Hom-(co)algebra structure on a space. Characterizations for solutions of Hom-Yang–Baxter equations arising from monoidal Hom-(co)algebra structures are given, and a monoidal Hom-(co)algebra structure which produces such a solution is constructed.  相似文献   
926.
927.
Lamarckian learning has been introduced into evolutionary computation as local search mechanism. The relevant research topic, memetic computation, has received significant amount of interests. In this study, a novel Lamarckian learning strategy is designed for improving the Nondominated Neighbor Immune Algorithm, a novel hybrid multi-objective optimization algorithm, Multi-objective Lamarckian Immune Algorithm (MLIA), is proposed. The Lamarckian learning performs a greedy search which proceeds towards the goal along the direction obtained by Tchebycheff approach and generates the improved progenies or improved decision vectors, so single individual will be optimized locally and the newcomers yield an enhanced exploitation around the nondominated individuals in less-crowded regions of the current trade-off front. Simulation results based on twelve benchmark problems show that MLIA outperforms the original immune algorithm and NSGA-II in approximating Pareto-optimal front in most of the test problems. When compared with the state of the art algorithm MOEA/D, MLIA shows better performance in terms of the coverage of two sets metric, although it is laggard in the hypervolume metric.  相似文献   
928.
929.
The minimax concave penalty (MCP) has been demonstrated theoretically and practically to be effective in nonconvex penalization for variable selection and parameter estimation. In this paper, we develop an efficient alternating direction method of multipliers (ADMM) with continuation algorithm for solving the MCP-penalized least squares problem in high dimensions. Under some mild conditions, we study the convergence properties and the Karush–Kuhn–Tucker (KKT) optimality conditions of the proposed method. A high-dimensional BIC is developed to select the optimal tuning parameters. Simulations and a real data example are presented to illustrate the efficiency and accuracy of the proposed method.  相似文献   
930.
Considered in this paper is a class of singular boundary value problem, arising in hydrodynamics and nonlinear field theory, when centrally bubble-type solutions are sought: \((p(t)u0)0 = c(t)p(t)f(u); u0(0) = 0; u(+1) = L > 0\) in the half-line \([0;+1)\), where \(p(0) = 0\). We are interested in strictly increasing solutions of this problem in \([0;1)\) having just one zero in \((0;+1) \)and finite limit at zero, which has great importance in applications or pure and applied mathematics. Su±cient conditions of the existence of such solutions are obtained by applying the critical point theory and by using shooting argument [9,10] to better analysis the properties of certain solutions associated with the singular di®erential equation. To the authors' knowledge, for the first time, the above problem is dealt with when f satis¯es non-Lipschitz condition. Recent results in the literature are generalized and signi¯cantly improved.  相似文献   
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