The existence of common fixed points for a pair of Lipschitzian mappings in Banach spaces is proved. By using this result, some common fixed point theorems are also established for these mappings in Hilbert spaces, in...The existence of common fixed points for a pair of Lipschitzian mappings in Banach spaces is proved. By using this result, some common fixed point theorems are also established for these mappings in Hilbert spaces, in L p spaces, in Hardy spaces H p, and in Sobolev spaces H r,p , for 1<p<+∞ and r≥0.展开更多
Let G be a semitopological semigroup. Let C be a closed convex subset of a uniformly convex Banaeh space E with a Frechet differentiable norm, and T = {Tt ： t ∈ G} be a continuous representation of G as nearly asymp...Let G be a semitopological semigroup. Let C be a closed convex subset of a uniformly convex Banaeh space E with a Frechet differentiable norm, and T = {Tt ： t ∈ G} be a continuous representation of G as nearly asymptotically nonexpansive type mappings of C into itself such that the common fixed point set F（T） of T in C is nonempty. It is shown that if G is right reversible, then for each almost-orbit u（.） of T, ∩s∈G ^-CO{u（t） ： t ≥ s} ∩ F（T） consists of at most one point. Furthermore, ∩s∈G ^-CO{Ttx ： t ≥ s} ∩ F（T） is nonempty for each x ∈ C if and only if there exists a nonlinear ergodic retraction P of C onto F（T） such that PTs - TsP = P for all s ∈ G and Px ∈^-CO{Ttx ： s ∈ G} for each x ∈ C. This result is applied to study the problem of weak convergence of the net {u（t） ： t ∈ G} to a common fixed point of T.展开更多
Itis shown that any fixed point of each Lipschitzian,strictly pseudocontractive map- ping T on a closed convex subset K of a Banach space X may be norm approximated by Ishikawa iterative procedure.The argument in th...Itis shown that any fixed point of each Lipschitzian,strictly pseudocontractive map- ping T on a closed convex subset K of a Banach space X may be norm approximated by Ishikawa iterative procedure.The argument in this paper provides a convergence rate estimate. Moreover the resultin this paper improves,generalizes and summarizes some important and el- egant recent results展开更多
The concept of controllable mapping,which is a kind of Lipschitzian mapping,is induced.In certain case,any controllable mapping,on a closed convex subset of Banach space,has at least onefixed point,and its Mann iterat...The concept of controllable mapping,which is a kind of Lipschitzian mapping,is induced.In certain case,any controllable mapping,on a closed convex subset of Banach space,has at least onefixed point,and its Mann iterative sequence converges strongly to the fixed point.Moreover,theestimation between the iterative sequence and the fixed point is,in sulface,as the same as in Banachcontractive mapping.展开更多
It is shown that any fixed point of a Lipschitzian,strictly pseudocontractive muping T on a closed convex subset K of a Banach space X may be approximated by Ishikawa iterative procedure.The results in this paper pro...It is shown that any fixed point of a Lipschitzian,strictly pseudocontractive muping T on a closed convex subset K of a Banach space X may be approximated by Ishikawa iterative procedure.The results in this paper provide the new convergence criteria and novel convergence rate estimate for Ishikawa iterative sequence.展开更多
Let C be a nonempty bounded closed convex subset of a Banach space X, and T : C → C be uniformly L-Lipschitzian with L ≥ 1 and asymptotically pseudocontractive with a sequence {kn}(?)[1, ∞), limn→∞ kn = 1. Fix u ...Let C be a nonempty bounded closed convex subset of a Banach space X, and T : C → C be uniformly L-Lipschitzian with L ≥ 1 and asymptotically pseudocontractive with a sequence {kn}(?)[1, ∞), limn→∞ kn = 1. Fix u ∈ C. For each n ≥ 1, xn is a unique fixed point of the contraction Sn(x) = (1 - (tn)/(Lkn))u + (tn)/(Lkn)Tnx(?)x ∈ C, where {tn}(?)[0,1). Under suitable conditions, the strong convergence of the sequence{xn}to a fixed point of T is characterized.展开更多
Let G be a semitopological semigroup. Let C be a nonempty subset of a Hilbert space and J ={T t:t∈G} be a representation of G as asymptotically nonexpansive type mappings of C into itself such ...Let G be a semitopological semigroup. Let C be a nonempty subset of a Hilbert space and J ={T t:t∈G} be a representation of G as asymptotically nonexpansive type mappings of C into itself such that the common fixed point set F(J) of J in C is nonempty. It is proved that ∩s∈G co {T ts x:t∈G}∩F(J) is nonempty for each x ∈ C if and only if there exists a nonexpansive retraction P of C onto F(J) such that PT s=T sP=P for all s∈G and P(x) is in the closed convex hull of {T sx:s∈G}, x∈C . This result shows that many key conditions in [1-4, 9, 12-15 ] are not necessary.展开更多
文摘The existence of common fixed points for a pair of Lipschitzian mappings in Banach spaces is proved. By using this result, some common fixed point theorems are also established for these mappings in Hilbert spaces, in L p spaces, in Hardy spaces H p, and in Sobolev spaces H r,p , for 1<p<+∞ and r≥0.
基金supported by the Teaching and Research Award Fund for Outstanding Young Teachers in Higher Education Institutions of MOE, Chinathe Dawn Program Foundation in Shanghai
文摘Let G be a semitopological semigroup. Let C be a closed convex subset of a uniformly convex Banaeh space E with a Frechet differentiable norm, and T = {Tt ： t ∈ G} be a continuous representation of G as nearly asymptotically nonexpansive type mappings of C into itself such that the common fixed point set F（T） of T in C is nonempty. It is shown that if G is right reversible, then for each almost-orbit u（.） of T, ∩s∈G ^-CO{u（t） ： t ≥ s} ∩ F（T） consists of at most one point. Furthermore, ∩s∈G ^-CO{Ttx ： t ≥ s} ∩ F（T） is nonempty for each x ∈ C if and only if there exists a nonlinear ergodic retraction P of C onto F（T） such that PTs - TsP = P for all s ∈ G and Px ∈^-CO{Ttx ： s ∈ G} for each x ∈ C. This result is applied to study the problem of weak convergence of the net {u（t） ： t ∈ G} to a common fixed point of T.
基金This project was supported both by the National Natural Science Foundation of China (1 980 1 0 2 3 ) andby the Teaching and Research Award Fund for Outstanding Young Teachers in Higher Education Institu-tions of MOEP.R.C.
文摘Itis shown that any fixed point of each Lipschitzian,strictly pseudocontractive map- ping T on a closed convex subset K of a Banach space X may be norm approximated by Ishikawa iterative procedure.The argument in this paper provides a convergence rate estimate. Moreover the resultin this paper improves,generalizes and summarizes some important and el- egant recent results
文摘The concept of controllable mapping,which is a kind of Lipschitzian mapping,is induced.In certain case,any controllable mapping,on a closed convex subset of Banach space,has at least onefixed point,and its Mann iterative sequence converges strongly to the fixed point.Moreover,theestimation between the iterative sequence and the fixed point is,in sulface,as the same as in Banachcontractive mapping.
基金Supported by the Teaching and Research Award Fund for Outstanding Young Teachers in Higher Ed-ucation Institutions of MOE,P.R.C.
文摘It is shown that any fixed point of a Lipschitzian,strictly pseudocontractive muping T on a closed convex subset K of a Banach space X may be approximated by Ishikawa iterative procedure.The results in this paper provide the new convergence criteria and novel convergence rate estimate for Ishikawa iterative sequence.
基金The Teaching and Research Award Fund for Outstanding Young Teachers in Higher Education Institutions of MOE, China, and The Dawn Program Fund in Shanghai.
文摘Let C be a nonempty bounded closed convex subset of a Banach space X, and T : C → C be uniformly L-Lipschitzian with L ≥ 1 and asymptotically pseudocontractive with a sequence {kn}(?)[1, ∞), limn→∞ kn = 1. Fix u ∈ C. For each n ≥ 1, xn is a unique fixed point of the contraction Sn(x) = (1 - (tn)/(Lkn))u + (tn)/(Lkn)Tnx(?)x ∈ C, where {tn}(?)[0,1). Under suitable conditions, the strong convergence of the sequence{xn}to a fixed point of T is characterized.
文摘Let G be a semitopological semigroup. Let C be a nonempty subset of a Hilbert space and J ={T t:t∈G} be a representation of G as asymptotically nonexpansive type mappings of C into itself such that the common fixed point set F(J) of J in C is nonempty. It is proved that ∩s∈G co {T ts x:t∈G}∩F(J) is nonempty for each x ∈ C if and only if there exists a nonexpansive retraction P of C onto F(J) such that PT s=T sP=P for all s∈G and P(x) is in the closed convex hull of {T sx:s∈G}, x∈C . This result shows that many key conditions in [1-4, 9, 12-15 ] are not necessary.
