For a continuous,increasing functionω:[0,∞)→C of finite exponential type,we establish a Hille-Yosida type theorem for strongly continuous α-times(α>0)integrated cosine operator functions with O(ω).It includes...For a continuous,increasing functionω:[0,∞)→C of finite exponential type,we establish a Hille-Yosida type theorem for strongly continuous α-times(α>0)integrated cosine operator functions with O(ω).It includes the corresponding results for n-times integrated cosine operator functions that are polynomially bounded and exponentially bounded.展开更多
For a continuous increasing function ω : [0, ∞) → (0, ∞) of finite exponetial type, we establish a Hille-Yosida type theorem for strongly continuous integrated cosine operator functions with O(ω). It includ...For a continuous increasing function ω : [0, ∞) → (0, ∞) of finite exponetial type, we establish a Hille-Yosida type theorem for strongly continuous integrated cosine operator functions with O(ω). It includes the well-known polynomially bounded and exponentially bounded cases.展开更多
In this paper we obtained general representation formulae for strongly continuous cosine operator functions via probabilistic approach,which include Webb's[1]and Shaw's[2]formulae and some new one as special c...In this paper we obtained general representation formulae for strongly continuous cosine operator functions via probabilistic approach,which include Webb's[1]and Shaw's[2]formulae and some new one as special cases.We also give the quantitative estimations for the general formulae.展开更多
Some basic properties of daul cosine operator function are given. The concept and characterization of θ-reflexivity with respect to cosine operator function are first studied.
In this paper,we proved that the infinitesimal generator of a strongly continuous cosine operator function is preserved under the time-dependent perturbation in the sun-reflexive case,where the perturbed operator is ...In this paper,we proved that the infinitesimal generator of a strongly continuous cosine operator function is preserved under the time-dependent perturbation in the sun-reflexive case,where the perturbed operator is a bounded linear operator from X into a bigger space Xθ(not X),then the corresponding 2-order abstract Cauchy problem is uniformly well-posed.展开更多
The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, wher...The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, where A is a closed operator on Banach space X. The case that the problem is ill-posed is treated, and two subspaces Y(A, k) and H(A, ω) are introduced. Y(A, k) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v( t, x) such that ess sup{(1+t)^-k|d/(dt)〈v(t,x),x^*〉|:t≥0,x^*∈X^*,|x^*‖≤1}〈+∞. H(A, ω) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v(t,x)such that ess sup{e^-ωl|d/(dt)〈v(t,x),x^*)|:t≥0,x^*∈X^*,‖x^*‖≤1}〈+∞. The following conclusions are proved that Y(A, k) and H(A, ω) are Banach spaces, and both are continuously embedded in X; the restriction operator A | Y(A,k) generates a once-integrated cosine operator family { C(t) }t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖Y(A,k)≤M(1+t)^k,arbitary t≥0; the restriction operator A |H(A,ω) generates a once- integrated cosine operator family {C(t)}t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖H(A,ω)≤≤Me^ωt,arbitary t≥0.展开更多
Some basic properties of dual cosine operator function are given. The concept and characterization of θ reflexivity with respect to cosine operator function are first studied.
For a continuous, increasing function ω : R^+ →R^+/{0} of finite exponential type, this paper introduces the set Z(A, ω) of all x in a Banach space X for which the second order abstract differential equation ...For a continuous, increasing function ω : R^+ →R^+/{0} of finite exponential type, this paper introduces the set Z(A, ω) of all x in a Banach space X for which the second order abstract differential equation (2) has a mild solution such that [ω(t)]^-1u(t,x) is uniformly continues on R^+, and show that Z(A, ω) is a maximal Banach subspace continuously embedded in X, where A ∈ B(X) is closed. Moreover, A[z(A,ω) generates an O(ω(t)) strongly continuous cosine operator function family.展开更多
基金Supported by the Natural Science Foundation of Department of Education of Jiangsu Province(06KJD110087) Supported by the Youth Foundation of NanJing Audit University(NSK2009/C04)
文摘For a continuous,increasing functionω:[0,∞)→C of finite exponential type,we establish a Hille-Yosida type theorem for strongly continuous α-times(α>0)integrated cosine operator functions with O(ω).It includes the corresponding results for n-times integrated cosine operator functions that are polynomially bounded and exponentially bounded.
文摘For a continuous increasing function ω : [0, ∞) → (0, ∞) of finite exponetial type, we establish a Hille-Yosida type theorem for strongly continuous integrated cosine operator functions with O(ω). It includes the well-known polynomially bounded and exponentially bounded cases.
文摘In this paper we obtained general representation formulae for strongly continuous cosine operator functions via probabilistic approach,which include Webb's[1]and Shaw's[2]formulae and some new one as special cases.We also give the quantitative estimations for the general formulae.
基金Project Supported by the NSF of Henan Province and NSF of North China Institute of Water Conservancy and Hydroelectric Power
文摘Some basic properties of daul cosine operator function are given. The concept and characterization of θ-reflexivity with respect to cosine operator function are first studied.
文摘In this paper,we proved that the infinitesimal generator of a strongly continuous cosine operator function is preserved under the time-dependent perturbation in the sun-reflexive case,where the perturbed operator is a bounded linear operator from X into a bigger space Xθ(not X),then the corresponding 2-order abstract Cauchy problem is uniformly well-posed.
基金The Natural Science Foundation of Department ofEducation of Jiangsu Province (No06KJD110087)
文摘The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, where A is a closed operator on Banach space X. The case that the problem is ill-posed is treated, and two subspaces Y(A, k) and H(A, ω) are introduced. Y(A, k) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v( t, x) such that ess sup{(1+t)^-k|d/(dt)〈v(t,x),x^*〉|:t≥0,x^*∈X^*,|x^*‖≤1}〈+∞. H(A, ω) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v(t,x)such that ess sup{e^-ωl|d/(dt)〈v(t,x),x^*)|:t≥0,x^*∈X^*,‖x^*‖≤1}〈+∞. The following conclusions are proved that Y(A, k) and H(A, ω) are Banach spaces, and both are continuously embedded in X; the restriction operator A | Y(A,k) generates a once-integrated cosine operator family { C(t) }t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖Y(A,k)≤M(1+t)^k,arbitary t≥0; the restriction operator A |H(A,ω) generates a once- integrated cosine operator family {C(t)}t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖H(A,ω)≤≤Me^ωt,arbitary t≥0.
文摘Some basic properties of dual cosine operator function are given. The concept and characterization of θ reflexivity with respect to cosine operator function are first studied.
文摘For a continuous, increasing function ω : R^+ →R^+/{0} of finite exponential type, this paper introduces the set Z(A, ω) of all x in a Banach space X for which the second order abstract differential equation (2) has a mild solution such that [ω(t)]^-1u(t,x) is uniformly continues on R^+, and show that Z(A, ω) is a maximal Banach subspace continuously embedded in X, where A ∈ B(X) is closed. Moreover, A[z(A,ω) generates an O(ω(t)) strongly continuous cosine operator function family.