In this paper we introduce two sequences of operator functions and their dualfunctions: fk(t) = (flogt)k-(t-1)k/log^k+2t (k = 1,2,...), gk(t) = (t-1)k-logkt /log^k+1t (k = 1,2,...) and fk(t)tklog^k...In this paper we introduce two sequences of operator functions and their dualfunctions: fk(t) = (flogt)k-(t-1)k/log^k+2t (k = 1,2,...), gk(t) = (t-1)k-logkt /log^k+1t (k = 1,2,...) and fk(t)tklog^k+1t/(tlogt)k-(t-1)^k(k=1,2…),gk(t)=t^klog^k+1t/(t-1)^k-log^kt(k=1,2…)defined onWe find that they are all operator monotone functions with respect to the strictly chaoticorder and some ordinary orders among positive invertible operators. Indeed, we extend theresults of the operator monotone function tlogt-t+1/log^2t which is widely used in the theory of heat transfer of the heat engineering and fluid mechanics[1].展开更多
We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on ...We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on F(p,pα-2,s),which generalizes the existing results and answers a question raised in[A.Anderson,Integral Equations Operator Theory,69(2011),no.1,87-99].For the Volterra operator J_(g),we show that,for 0<α≤1,J_(g)never has a closed range on F(p,pα-2,s).We then prove that the notions of compactness,weak compactness and strict singularity coincide in the case of J_(g)acting on F(p,p-2,s).展开更多
In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linea...In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linear operator.展开更多
In this paper,we introduce a general hybrid iterative method to find an infinite family of strict pseudo-contractions in a q-uniformly smooth and strictly convex Banach space.Moreover,we show that the sequence defined...In this paper,we introduce a general hybrid iterative method to find an infinite family of strict pseudo-contractions in a q-uniformly smooth and strictly convex Banach space.Moreover,we show that the sequence defined by the iterative method converges strongly to a common element of the set of fixed points,which is the unique solution of the variational inequality<(λφ−νF)z,jq(z−z)>≤0,for z∈⋂_(i=1)^(∞)Γ(S_(i)).The results introduced in our work extend to some corresponding theorems.展开更多
文摘In this paper we introduce two sequences of operator functions and their dualfunctions: fk(t) = (flogt)k-(t-1)k/log^k+2t (k = 1,2,...), gk(t) = (t-1)k-logkt /log^k+1t (k = 1,2,...) and fk(t)tklog^k+1t/(tlogt)k-(t-1)^k(k=1,2…),gk(t)=t^klog^k+1t/(t-1)^k-log^kt(k=1,2…)defined onWe find that they are all operator monotone functions with respect to the strictly chaoticorder and some ordinary orders among positive invertible operators. Indeed, we extend theresults of the operator monotone function tlogt-t+1/log^2t which is widely used in the theory of heat transfer of the heat engineering and fluid mechanics[1].
基金partially supported by the Fundamental Research Funds for the Central Universities(GK202207018)of China。
文摘We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on F(p,pα-2,s),which generalizes the existing results and answers a question raised in[A.Anderson,Integral Equations Operator Theory,69(2011),no.1,87-99].For the Volterra operator J_(g),we show that,for 0<α≤1,J_(g)never has a closed range on F(p,pα-2,s).We then prove that the notions of compactness,weak compactness and strict singularity coincide in the case of J_(g)acting on F(p,p-2,s).
文摘In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linear operator.
基金supported by the National Natural Science Foundation of China(12001416,11771347 and 12031003)the Natural Science Foundations of Shaanxi Province(2021JQ-678).
文摘In this paper,we introduce a general hybrid iterative method to find an infinite family of strict pseudo-contractions in a q-uniformly smooth and strictly convex Banach space.Moreover,we show that the sequence defined by the iterative method converges strongly to a common element of the set of fixed points,which is the unique solution of the variational inequality<(λφ−νF)z,jq(z−z)>≤0,for z∈⋂_(i=1)^(∞)Γ(S_(i)).The results introduced in our work extend to some corresponding theorems.