排序方式: 共有79条查询结果,搜索用时 15 毫秒
71.
Genaro Lopez Victoria Martin Hong-Kun Xu 《Nonlinear Analysis: Real World Applications》2009,10(4):2369-2383
Perturbation techniques for nonexpansive mappings are studied. An iterative algorithm involving perturbed mappings in a Banach space is proposed and proved to be strongly convergent to a fixed point of the original mapping. These techniques are applied to solve the split feasibility problem and the multiple-sets split feasibility problem, and to find zeros of accretive operators. 相似文献
72.
73.
Strong convergence theorems are obtained for the CQ method for an Ishikawa iteration process, a contractive-type iteration process for nonexpansive mappings, and the proximal point algorithm for maximal monotone operators in Hilbert spaces. 相似文献
74.
Z. Hong-Kun T. Cao Zh. Dao-Sen X. Wen-Lin W. Ya-Qong Q. Qi-Shu 《Journal of Thermal Analysis and Calorimetry》2007,89(2):531-536
The non-isothermal decomposition kinetics of 4Na2SO4·2H2O2·NaCl have been investigated by simultaneous TG-DSC in nitrogen atmosphere and in air. The decomposition processes undergo
a single step reaction. The multivariate nonlinear regression technique is used to distinguish kinetic model of 4Na2SO4·2H2O2·NaCl. Results indicate that the reaction type Cn can well describe the decomposition process, the decomposition mechanism
is n-dimensional autocatalysis. The kinetic parameters, n, A and E are obtained via multivariate nonlinear regression. The n
th-order with autocatalysis model is used to simulate the thermal decomposition of 4Na2SO4·2H2O2·NaCl under isothermal conditions at various temperatures. The flow rate of gas has little effect on the decomposition of
4Na2SO4·2H2O2·NaCl. 相似文献
75.
A random billiard is a random dynamical system similar to an ordinary billiard system except that the standard specular reflection law is replaced with a more general stochastic operator specifying the post-collision distribution of velocities for any given pre-collision velocity. We consider such collision operators for certain random billiards that we call billiards with microstructure. Collisions modeled by these operators can still be thought of as elastic and time reversible. The operators are canonically determined by a second (deterministic) billiard system that models “microscopic roughness” on the billiard table boundary. Our main purpose here is to develop some general tools for the analysis of the collision operator of such random billiards. Among the main results, we give geometric conditions for these operators to be Hilbert-Schmidt and relate their spectrum and speed of convergence to stationary Markov chains with geometric features of the microscopic billiard structure. The relationship between spectral gap and the shape of the microstructure is illustrated with several simple examples. 相似文献
76.
We show that a compound Poisson distribution holds for scaled exceedances of observables \(\phi \) uniquely maximized at a periodic point \(\zeta \) in a variety of two-dimensional hyperbolic dynamical systems with singularities \((M,T,\mu )\), including the billiard maps of Sinai dispersing billiards in both the finite and infinite horizon case. The observable we consider is of form \(\phi (z)=-\ln d(z,\zeta )\) where d is a metric defined in terms of the stable and unstable foliation. The compound Poisson process we obtain is a Pólya-Aeppli distibution of index \(\theta \). We calculate \(\theta \) in terms of the derivative of the map T. Furthermore if we define \(M_n=\max \{\phi ,\ldots ,\phi \circ T^n\}\) and \(u_n (\tau )\) by \(\lim _{n\rightarrow \infty } n\mu (\phi >u_n (\tau ) )=\tau \) the maximal process satisfies an extreme value law of form \(\mu (M_n \le u_n)=e^{-\theta \tau }\). These results generalize to a broader class of functions maximized at \(\zeta \), though the formulas regarding the parameters in the distribution need to be modified. 相似文献
77.
Hong-Kun Xu 《Journal of Global Optimization》2006,36(1):115-125
A regularization method for the proximal point algorithm of finding a zero for a maximal monotone operator in a Hilbert space is proposed. Strong convergence of this algorithm is proved.Hong-Kun Xu: Supported in part by NRF 相似文献
78.
Let C be a closed convex subset of a real Hilbert space H and assume that T is an asymptotically κ-strict pseudo-contraction on C with a fixed point, for some 0≤κ<1. Given an initial guess x0∈C and given also a real sequence {αn} in (0, 1), the modified Mann’s algorithm generates a sequence {xn} via the formula: xn+1=αnxn+(1−αn)Tnxn, n≥0. It is proved that if the control sequence {αn} is chosen so that κ+δ<αn<1−δ for some δ∈(0,1), then {xn} converges weakly to a fixed point of T. We also modify this iteration method by applying projections onto suitably constructed closed convex sets to get an algorithm which generates a strongly convergent sequence. 相似文献
79.
An explicit hierarchical fixed point algorithm is introduced to solve monotone variational inequalities, which are governed
by a pair of nonexpansive mappings, one of which is used to define the governing operator and the other to define the feasible
set. These kinds of variational inequalities include monotone inclusions and convex optimization problems to be solved over
the fixed point sets of nonexpansive mappings. Strong convergence of the algorithm is proved under different circumstances
of parameter selections. Applications in hierarchical minimization problems are also included. 相似文献