Some new reverses of the Cauchy-Schwarz inequality in inner product spaces are presented in this paper. As an application of the main result, a formula for error estimate concerning Cauchy-Schwarz’s inequality is pro...Some new reverses of the Cauchy-Schwarz inequality in inner product spaces are presented in this paper. As an application of the main result, a formula for error estimate concerning Cauchy-Schwarz’s inequality is provided. The results obtained in the paper complement and improve some recent work about this topic.展开更多
We prove, using the fixed point approach, some results on hyperstability (in normed spaces) of the equation that defines the generalization of p-Wright affine functions and show that they yield a simple characteriza...We prove, using the fixed point approach, some results on hyperstability (in normed spaces) of the equation that defines the generalization of p-Wright affine functions and show that they yield a simple characterization of the complex inner product spaces.展开更多
In this paper, first introduce and define an intuitionistic Menger inner product space, and then, obtain a new fixed point theorem in a complete intuitionistic Menger inner product space. As an application, the result...In this paper, first introduce and define an intuitionistic Menger inner product space, and then, obtain a new fixed point theorem in a complete intuitionistic Menger inner product space. As an application, the results are used to study the existence and uniqueness of the solution to a linear Volterra integral equation.展开更多
In [1],a family of angles are defined in normed linear spaces. In this paper,it is shown that if anyone of the angles satisfies certain euclidean triangle congruence properties,the space must be an inner product space.
Let H and K be indefinite inner product spaces. This paper shows that a bijective map φ:B(H) →B(K) satisfies φ(AB^+ + B^+A) = φ(A)φ(B)^+ + φ(B)^+φ(A) for every pair A, B ∈ B(H) if and on...Let H and K be indefinite inner product spaces. This paper shows that a bijective map φ:B(H) →B(K) satisfies φ(AB^+ + B^+A) = φ(A)φ(B)^+ + φ(B)^+φ(A) for every pair A, B ∈ B(H) if and only if either φ(A) = cUAU^+ for all A or φ(A) = cUA^+U^+ for all A; φ satisfies φ(AB^+A) = φ;(A)φ;(B)^+φ;(A) for every pair A, B ∈ B(H) if and only if either φ(A) = UAV for all A or φ(A) = UA^+V for all A, where At denotes the indefinite conjugate of A, U and V are bounded invertible linear or conjugate linear operators with U^tU = c^-1I and V^+V = cI for some nonzero real number c.展开更多
In this paper the linearly topological structure of Menger Probabilistic inner product space is discussed. In virtue of these, some more general convergence theorems, Pythagorean theorem, and the orthogonal projective...In this paper the linearly topological structure of Menger Probabilistic inner product space is discussed. In virtue of these, some more general convergence theorems, Pythagorean theorem, and the orthogonal projective theorem are established.展开更多
We present results on approximate solutions to the biadditive equationf(x+y,z-w)+f(x-y,z+w)=2f(x,z)-2f(y,w)on a restricted domain. The proof is based on a quite recent fixed point theorem in some function s...We present results on approximate solutions to the biadditive equationf(x+y,z-w)+f(x-y,z+w)=2f(x,z)-2f(y,w)on a restricted domain. The proof is based on a quite recent fixed point theorem in some function spaces. Our main results state that, under some weak natural assumptions, functions satisfying the equation approximately (in some sense) must be actually solutions to it. In this way we obtain inequalities characterizing biadditive mappings and inner product spaces. Our outcomes are connected with the well known issues of Ulam stability and hyperstability.展开更多
A new concept of the X-M-PN space is introduced, and the acute angle principle in the X-M-PN space is proved. Meanwhile, some new results are obtained.
Mathematical models for phenomena in the physical sciences are typically parameter-dependent, and the estimation of parameters that optimally model the trends suggested by experimental observation depends on how model...Mathematical models for phenomena in the physical sciences are typically parameter-dependent, and the estimation of parameters that optimally model the trends suggested by experimental observation depends on how model-observation discrepancies are quantified. Commonly used parameter estimation techniques based on least-squares minimization of the model-observation discrepancies assume that the discrepancies are quantified with the L<sup>2</sup>-norm applied to a discrepancy function. While techniques based on such an assumption work well for many applications, other applications are better suited for least-squared minimization approaches that are based on other norm or inner-product induced topologies. Motivated by an application in the material sciences, the new alternative least-squares approach is defined and an insightful analytical comparison with a baseline least-squares approach is provided.展开更多
Let ,4 and B be unital C*-algebras, and let J∈A,L∈B be Hermitian invertible elements. For every T∈A and S∈B, define T^+J=J^-1T*J and ,S^+L=^L-1,S*L. Then in such a way we endow the C*-algebras A and B with i...Let ,4 and B be unital C*-algebras, and let J∈A,L∈B be Hermitian invertible elements. For every T∈A and S∈B, define T^+J=J^-1T*J and ,S^+L=^L-1,S*L. Then in such a way we endow the C*-algebras A and B with indefinite structures. We characterize firstly the Jordan (J, L)+homomorphisms on C*-algebras. As applications, we further classify the bounded linear maps Ф: A →B preserving (J, L)-unitary elements. When ,4 = B(H) and B=B(K), where H and K are infinite dimensional and complete indefinite inner product spaces on real or complex fields, we prove that indefinite-unitary preserving bounded linear surjections are of the form T→UVTV^-1 (任意T∈B(H)) or T→UVT^+V^-1(任意T∈B(H)), where U∈B(K) is indefinite unitary and, V : H→ K is generalized indefinite unitary in the first form and generalized indefinite anti-unitary in the second one. Some results on indefinite orthogonality preserving additive maps are also given.展开更多
The paper proposes a new text similarity computing method based on concept similarity in Chinese text processing. The new method converts text to words vector space model at first, and then splits words into a set of ...The paper proposes a new text similarity computing method based on concept similarity in Chinese text processing. The new method converts text to words vector space model at first, and then splits words into a set of concepts. Through computing the inner products between concepts, it obtains the similarity between words. The new method computes the similarity of text based on the similarity of words at last. The contributions of the paper include: 1) propose a new computing formula between words; 2) propose a new text similarity computing method based on words similarity; 3) successfully use the method in the application of similarity computing of WEB news; and 4) prove the validity of the method through extensive experiments.展开更多
基金The NNSF (10271053) of China and the Science Foundation (HGDJJ03001) of Naval University of Engineering.
文摘Some new reverses of the Cauchy-Schwarz inequality in inner product spaces are presented in this paper. As an application of the main result, a formula for error estimate concerning Cauchy-Schwarz’s inequality is provided. The results obtained in the paper complement and improve some recent work about this topic.
文摘We prove, using the fixed point approach, some results on hyperstability (in normed spaces) of the equation that defines the generalization of p-Wright affine functions and show that they yield a simple characterization of the complex inner product spaces.
基金Project supported by the Natural Science Foundation of Yibin University (No. 2009Z01)
文摘In this paper, first introduce and define an intuitionistic Menger inner product space, and then, obtain a new fixed point theorem in a complete intuitionistic Menger inner product space. As an application, the results are used to study the existence and uniqueness of the solution to a linear Volterra integral equation.
文摘In [1],a family of angles are defined in normed linear spaces. In this paper,it is shown that if anyone of the angles satisfies certain euclidean triangle congruence properties,the space must be an inner product space.
基金Project supported by the National Natural Science Foundation of China (No.10471082) the Shanxi Provincial Natural Science Foundation of China (No.20021005).
文摘Let H and K be indefinite inner product spaces. This paper shows that a bijective map φ:B(H) →B(K) satisfies φ(AB^+ + B^+A) = φ(A)φ(B)^+ + φ(B)^+φ(A) for every pair A, B ∈ B(H) if and only if either φ(A) = cUAU^+ for all A or φ(A) = cUA^+U^+ for all A; φ satisfies φ(AB^+A) = φ;(A)φ;(B)^+φ;(A) for every pair A, B ∈ B(H) if and only if either φ(A) = UAV for all A or φ(A) = UA^+V for all A, where At denotes the indefinite conjugate of A, U and V are bounded invertible linear or conjugate linear operators with U^tU = c^-1I and V^+V = cI for some nonzero real number c.
基金Supported by the Natural Science Foundation of the Education Committee ofJiangsu Province
文摘In this paper the linearly topological structure of Menger Probabilistic inner product space is discussed. In virtue of these, some more general convergence theorems, Pythagorean theorem, and the orthogonal projective theorem are established.
文摘We present results on approximate solutions to the biadditive equationf(x+y,z-w)+f(x-y,z+w)=2f(x,z)-2f(y,w)on a restricted domain. The proof is based on a quite recent fixed point theorem in some function spaces. Our main results state that, under some weak natural assumptions, functions satisfying the equation approximately (in some sense) must be actually solutions to it. In this way we obtain inequalities characterizing biadditive mappings and inner product spaces. Our outcomes are connected with the well known issues of Ulam stability and hyperstability.
文摘A new concept of the X-M-PN space is introduced, and the acute angle principle in the X-M-PN space is proved. Meanwhile, some new results are obtained.
文摘Mathematical models for phenomena in the physical sciences are typically parameter-dependent, and the estimation of parameters that optimally model the trends suggested by experimental observation depends on how model-observation discrepancies are quantified. Commonly used parameter estimation techniques based on least-squares minimization of the model-observation discrepancies assume that the discrepancies are quantified with the L<sup>2</sup>-norm applied to a discrepancy function. While techniques based on such an assumption work well for many applications, other applications are better suited for least-squared minimization approaches that are based on other norm or inner-product induced topologies. Motivated by an application in the material sciences, the new alternative least-squares approach is defined and an insightful analytical comparison with a baseline least-squares approach is provided.
基金The NNSF (10471082) of Chinathe YSF (20031009) of Shanxi ProvinceTsinghua Basic Research Foundation
文摘Let ,4 and B be unital C*-algebras, and let J∈A,L∈B be Hermitian invertible elements. For every T∈A and S∈B, define T^+J=J^-1T*J and ,S^+L=^L-1,S*L. Then in such a way we endow the C*-algebras A and B with indefinite structures. We characterize firstly the Jordan (J, L)+homomorphisms on C*-algebras. As applications, we further classify the bounded linear maps Ф: A →B preserving (J, L)-unitary elements. When ,4 = B(H) and B=B(K), where H and K are infinite dimensional and complete indefinite inner product spaces on real or complex fields, we prove that indefinite-unitary preserving bounded linear surjections are of the form T→UVTV^-1 (任意T∈B(H)) or T→UVT^+V^-1(任意T∈B(H)), where U∈B(K) is indefinite unitary and, V : H→ K is generalized indefinite unitary in the first form and generalized indefinite anti-unitary in the second one. Some results on indefinite orthogonality preserving additive maps are also given.
基金Supported by the China Postdoctoral Science Foundation (Grant No. 20060400002)the Sichuan Youth Science and Technology Foundation of China (Grant No. 08JJ0109)+2 种基金the National Natural Science Foundation of China (Grant Nos.60473051, 60503037)the National High-tech Re- search and Development of China (Grant No. 2006AA01Z230)the Natural Science Foundation of Beijing Natural Science Foundation (Grant No. 4062018)
文摘The paper proposes a new text similarity computing method based on concept similarity in Chinese text processing. The new method converts text to words vector space model at first, and then splits words into a set of concepts. Through computing the inner products between concepts, it obtains the similarity between words. The new method computes the similarity of text based on the similarity of words at last. The contributions of the paper include: 1) propose a new computing formula between words; 2) propose a new text similarity computing method based on words similarity; 3) successfully use the method in the application of similarity computing of WEB news; and 4) prove the validity of the method through extensive experiments.