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Analysis of chaos behaviors of a bistable piezoelectric cantilever power generation system by the second-order Melnikov function 被引量:5
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作者 Shu Sun Shu-Qian Cao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第1期200-207,共8页
By applying the second order Melnikov function, the chaos behaviors of a bistable piezoelectric cantilever power generation system are analyzed. Firstly, the conditions for emerging chaos of the system are derived by ... By applying the second order Melnikov function, the chaos behaviors of a bistable piezoelectric cantilever power generation system are analyzed. Firstly, the conditions for emerging chaos of the system are derived by the second order Melnikov function. Secondly, the effects of each item in chaos threshold expression are analyzed. The excitation frequency and resistance values, which have the most influence on chaos threshold value, are found. The result from the second order Melnikov function is more accurate compared with that from the first order Melnikov function. Finally, the attraction basins of large amplitude motions under different exciting frequency, exciting amplitude, and resistance parameters are given. 展开更多
关键词 Bistable piezoelectric cantilever beam second order Melnikov function Homoclinic bifurcation Basin of attraction
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Second Hankel Determinants and Fekete-Szegö Inequalities for Some Sub-Classes of Bi-Univalent Functions with Respect to Symmetric and Conjugate Points Related to a Shell Shaped Region 被引量:2
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作者 Rayaprolu Bharavi Sharma Kalikota Rajya Laxmi 《Analysis in Theory and Applications》 CSCD 2018年第4期358-373,共16页
In this paper, we have investigated second Hankel determinants and FeketeSzeg? inequalities for some subclasses of Bi-univalent functions with respect to symmetric and Conjugate points which are subordinate to a shell... In this paper, we have investigated second Hankel determinants and FeketeSzeg? inequalities for some subclasses of Bi-univalent functions with respect to symmetric and Conjugate points which are subordinate to a shell shaped region in the open unit disc ?. 展开更多
关键词 Analytic functions univalent functions Bi-univalent functions second Hankel determinants Fekete-Szeg?inequalities symmetric points conjugate points
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Lattice Green's Function for Infinite Square Lattice in the Second Nearest-Neighbour Interaction Approximation 被引量:1
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作者 FAN Hong-Yi LIN Jing-Xian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第11期541-546,共6页
In dealing with the square lattice model,we replace the traditionally needed Born-Von Karmann periodic boundary condition with additional Hamiltonian terms to make up a ring lattice.In doing so,the lattice Green's... In dealing with the square lattice model,we replace the traditionally needed Born-Von Karmann periodic boundary condition with additional Hamiltonian terms to make up a ring lattice.In doing so,the lattice Green's function of an infinite square lattice in the second nearest-neighbour interaction approximation can be derived by means of the matrix Green's function method.It is shown that the density of states may change when the second nearest-neighbour interaction is turned on. 展开更多
关键词 matrix Green's function method the second NEAREST-NEIGHBOUR INTERACTION
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Probabilistic density function estimation of geotechnical shear strength parameters using the second Chebyshev orthogonal polynomial 被引量:1
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作者 李夕兵 宫凤强 邓建 《Journal of Central South University of Technology》 EI 2006年第3期275-280,共6页
A method to estimate the probabilistic density function (PDF) of shear strength parameters was proposed. The second Chebyshev orthogonal polynomial(SCOP) combined with sample moments (the origin moments) was use... A method to estimate the probabilistic density function (PDF) of shear strength parameters was proposed. The second Chebyshev orthogonal polynomial(SCOP) combined with sample moments (the origin moments) was used to approximate the PDF of parameters. X^2 test was adopted to verify the availability of the method. It is distribution-free because no classical theoretical distributions were assumed in advance and the inference result provides a universal form of probability density curves. Six most commonly-used theoretical distributions named normal, lognormal, extreme value Ⅰ , gama, beta and Weibull distributions were used to verify SCOP method. An example from the observed data of cohesion c of a kind of silt clay was presented for illustrative purpose. The results show that the acceptance levels in SCOP are all smaller than those in the classical finite comparative method and the SCOP function is more accurate and effective in the reliability analysis of geotechnical engineering. 展开更多
关键词 shear strength second Chebyshev orthogonal polynomial probabilistic density function origin moments
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MEROMORPHIC p-VALENT FUNCTION WITH FIXED SECOND NEGATIVE COEFFICIENTS
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作者 M.Darus 《Analysis in Theory and Applications》 2005年第2期132-142,共11页
In this paper we consider the class ∑^*(p,α,β,k,c) consisting of analytic functions with negativecoefficients and fixed second coefficient. The object of the present paper is to give coefficient estimates, conve... In this paper we consider the class ∑^*(p,α,β,k,c) consisting of analytic functions with negativecoefficients and fixed second coefficient. The object of the present paper is to give coefficient estimates, convex linear combinations, some distortion theorems and radii of starlikeness and convexity for f(z) in the class ∑^*(p,α,β,k,c) . 展开更多
关键词 analytic function meromorphic function negative coefficient fixed second negative coefficient growth and distortion theorem
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Some Properties of Analytic Functions with the Fixed Second Coefficients
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作者 Oh Sang Kwon 《Advances in Pure Mathematics》 2014年第5期194-202,共9页
In this paper, we investigate some argument properties for analytic functions with fixed second coefficient and positive real part. And we apply the argument properties to the functions that are analytic and normalize... In this paper, we investigate some argument properties for analytic functions with fixed second coefficient and positive real part. And we apply the argument properties to the functions that are analytic and normalized. In particular, the order of strongly starlikeness of strongly convex functions with fixed second coefficients is given. 展开更多
关键词 Analytic functionS Argument Estimate Fixed second COEFFICIENTS STRONGLY STARLIKE functionS STRONGLY Convex functionS
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Parametric Approach for the Normal Luenberger Function Observer Design in Second-order Descriptor Linear Systems 被引量:2
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作者 Bin Zhou Guang-Ren Duan Yun-Li Wu 《International Journal of Automation and computing》 EI 2008年第2期125-131,共7页
In this paper, the normal Luenberger function observer design for second-order descriptor linear systems is considered. It is shown that the main procedure of the design is to solve a so-called second-order generalize... In this paper, the normal Luenberger function observer design for second-order descriptor linear systems is considered. It is shown that the main procedure of the design is to solve a so-called second-order generalized Sylvester-observer matrix equation. Based on an explicit parametric solution to this equation, a parametric solution to the normal Luenberger function observer design problem is given. The design degrees of freedom presented by explicit parameters can be further utilized to achieve some additional design requirements. 展开更多
关键词 second-order descriptor linear systems normal Luenberger functions observer Sylvester matrix equation parametricsolutions
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CHEBYSHEV APPROXIMATION OF THE SECOND KIND OF MODIFIED BESSEL FUNCTION OF ORDER ZERO
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作者 张璟 周哲玮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第5期483-487,共5页
The second kind of modified Bessel function of order zero is the solutions of many problems in engineering. Modified Bessel equation is transformed by exponential transformation and expanded by J.P.Boyd's rational... The second kind of modified Bessel function of order zero is the solutions of many problems in engineering. Modified Bessel equation is transformed by exponential transformation and expanded by J.P.Boyd's rational Chebyshev basis. 展开更多
关键词 second kind of modified Bessel function of order zero exponential transformation rational Chebyshev basis
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α-times Integrated Regularized Cosine Functions and Second Order Abstract Cauchy Problems
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作者 Zhang Jizhou(张寄洲) +1 位作者 Tao Youshan(陶有山) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期51-54,共4页
In this paper, α-times integrated C-regularized cosine functions and mild α-times integrated C-existence families of second order are introduced. Equivalences are proved among α-times integrated C-regularized cosin... In this paper, α-times integrated C-regularized cosine functions and mild α-times integrated C-existence families of second order are introduced. Equivalences are proved among α-times integrated C-regularized cosine function for a linear operator A, C-wellposed of (α+1)-times abstract Cauchy problem and mild a -times integrated C-existence family of second order for A when the commutable condition is satisfied. In addition, if A = C-1AC, they are also equivalent to A generating the α -times integrated C-regularized cosine function. The characterization of an exponentially bounded mild α -times integrated C-existence family of second order is given out in terms of a Laplace transform. 展开更多
关键词 a-times integrated regularized cosine function mild a-times integrated C-existence family of second order C-wellposed second order abstract Cauchy problem.
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Some Results on the Space of Bounded Second Variation Functions in the Sense of Shiba
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作者 Liliana Pérez Ebner Pineda Luz Rodríguez 《Advances in Pure Mathematics》 2020年第5期245-258,共14页
In this paper, we study the structure of the space of functions of bounded second variation in the sense of Shiba;an integral representation theorem is also proved and necessary conditions are given for that the space... In this paper, we study the structure of the space of functions of bounded second variation in the sense of Shiba;an integral representation theorem is also proved and necessary conditions are given for that the space be closed under composition of functions. Another significant result is the proof that this space of bounded second variation in the sense of Shiba is a Banach algebra, which is not immediate as it happens in other spaces of generalized bounded variation. 展开更多
关键词 functional Analysis BOUNDED VARIATION second BOUNDED VARIATION BANACH SPACE
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Design of Luenberger function observer with disturbance decoupling for matrix second-order linear systems-a parametric approach 被引量:1
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作者 Wu Yunli Duan Guangren 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期156-162,共7页
A simple method for disturbance decoupling for matrix second-order linear systems is proposed directly in matrix second-order framework via Luenberger function observers based on complete parametric eigenstructure ass... A simple method for disturbance decoupling for matrix second-order linear systems is proposed directly in matrix second-order framework via Luenberger function observers based on complete parametric eigenstructure assignment. By introducing the H2 norm of the transfer function from disturbance to estimation error, sufficient and necessary conditions for disturbance decoupling in matrix second-order linear systems are established and are arranged into constraints on the design parameters via Luenberger function observers in terms of the closed-loop eigenvalues and the group of design parameters provided by the eigenstructure assignment approach. Therefore, the disturbance decoupling problem is converted into an eigenstructure assignment problem with extra parameter constraints. A simple example is investigated to show the effect and simplicity of the approach. 展开更多
关键词 matrix second-order linear systems Luenberger function observers eigenstructure assignment disturbance decoupling
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An Attempt to Make Non-Elementary Functions That Are Giving Solutions to Some Second-Order Nonlinear Autonomous ODEs 被引量:2
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作者 Magne Stensland 《Journal of Applied Mathematics and Physics》 2022年第1期56-67,共12页
In this paper, we define an exponential function whose exponent is the product of a real number and the upper limit of integration in a non-elementary integral that can be arbitrary. We are using Abel’s methods, desc... In this paper, we define an exponential function whose exponent is the product of a real number and the upper limit of integration in a non-elementary integral that can be arbitrary. We are using Abel’s methods, described by Armitage and Eberlein. The key is to start with a non-elementary integral function, differentiating and inverting, and then define a set of functions. Differentiating these functions twice give second-order nonlinear ODEs that have the defined set of functions as solutions. 展开更多
关键词 Non-Elementary functions second-Order Nonlinear Autonomous ODE
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Predictors of graft function and survival in second kidney transplantation: A single center experience
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作者 Mahmoud Khalil Rabea Ahmed Gadelkareem +4 位作者 Medhat Ahmed Abdallah Mohamed Abdel-Basir Sayed FathyGaber Elanany Paolo Fornara Nasreldin Mohammed 《World Journal of Transplantation》 2023年第6期331-343,共13页
BACKGROUND The increasing kidney retransplantation rate has created a parallel field of research,including the risk factors and outcomes of this advanced form of renal replacement therapy.The presentation of experienc... BACKGROUND The increasing kidney retransplantation rate has created a parallel field of research,including the risk factors and outcomes of this advanced form of renal replacement therapy.The presentation of experiences from different kidney transplantation centers may help enrich the literature on kidney retransplantation,as a specific topic in the field of kidney transplantation.AIM To identify the risk factors affecting primary graft function and graft survival rates after second kidney transplantation(SKT).METHODS The records of SKT cases performed between January 1977 and December 2014 at a European tertiary-level kidney transplantation center were retrospectively reviewed and analyzed.Beside the descriptive characteristics,the survivals of patients and both the first and second grafts were described using Kaplan-Meier curves.In addition,Kaplan-Meier analyses were also used to estimate the survival probabilities at 1,3,5,and 10 post-operative years,as well as at the longest followup duration available.Moreover,bivariate associations between various predictors and the categorical outcomes were assessed,using the suitable biostatistical tests,according to the predictor type.RESULTS Out of 1861 cases of kidney transplantation,only 48 cases with SKT were eligible for studying,including 33 men and 15 women with a mean age of 42.1±13 years.The primary non-function(PNF)graft occurred in five patients(10.4%).In bivariate analyses,a high body mass index(P=0.009)and first graft loss due to acute rejection(P=0.025)were the only significant predictors of PNF graft.The second graft survival was reduced by delayed graft function in the first(P=0.008)and second(P<0.001)grafts.However,the effect of acute rejection within the first year after the first transplant did not reach the threshold of significance(P=0.053).The mean follow-up period was 59.8±48.6 mo.Censored graft/patient survival rates at 1,3,5 and 10 years were 90.5%/97.9%,79.9%/95.6%,73.7%/91.9%,and 51.6%/83.0%,respectively.CONCLUSION Non-immediate recovery modes of the first and second graft functions were significantly associated with unfavorable second graft survival rates.Patient and graft survival rates of SKT were similar to those of the first kidney transplantation. 展开更多
关键词 Graft failure Graft function KIDNEY Kidney retransplantation Primary non-function graft second kidney transplantation
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Generating functions for powers of second-order recurrence sequences
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作者 王晓霞 李梅 《Journal of Shanghai University(English Edition)》 CAS 2011年第6期517-521,共5页
For the sequences satisfying the recurrence relation of the second order,the generating functions for the products of the powers of these sequences are established.This study was from Carlita and Riordan who began a s... For the sequences satisfying the recurrence relation of the second order,the generating functions for the products of the powers of these sequences are established.This study was from Carlita and Riordan who began a study on closed form of generating functions for powers of second-order recurrence sequences.This investigation was completed by Stnica.Inspired by the recent work of Istva'n about the non-closed generating functions of the products of the powers of the second-order sequences,the authors give several extensions of Istva'n's results in this paper. 展开更多
关键词 generating function second-order sequence the Binet formula
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Second-Order Duality for Continuous Programming Containing Support Functions
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作者 Iqbal Husain Mashoob Masoodi 《Applied Mathematics》 2010年第6期534-541,共8页
A second-order dual problem is formulated for a class of continuous programming problem in which both objective and constrained functions contain support functions, hence it is nondifferentiable. Under second-order in... A second-order dual problem is formulated for a class of continuous programming problem in which both objective and constrained functions contain support functions, hence it is nondifferentiable. Under second-order invexity and second-order pseudoinvexity, weak, strong and converse duality theorems are established for this pair of dual problems. Special cases are deduced and a pair of dual continuous problems with natural boundary values is constructed. A close relationship between duality results of our problems and those of the corresponding (static) nonlinear programming problem with support functions is briefly outlined. 展开更多
关键词 Continuous PROGRAMMING second-ORDER INVEXITY second-ORDER PSEUDOINVEXITY second-ORDER DUALITY Nonlinear PROGRAMMING Support functions Natural Boundary VALUES
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Four New Examples of the Non-Elementary Expo-Elliptic Functions That Are Giving Solutions to Some Second-Order Nonlinear Autonomous ODEs
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作者 Magne Stensland 《Journal of Applied Mathematics and Physics》 2022年第4期1304-1324,共21页
In this paper, we define four new examples of the non-elementary expo-elliptic functions. This is an exponential function whose exponent is the product of a real number and the upper limit of integration in a non-elem... In this paper, we define four new examples of the non-elementary expo-elliptic functions. This is an exponential function whose exponent is the product of a real number and the upper limit of integration in a non-elementary integral that can be arbitrary. We are using Abel’s methods, described by Armitage and Eberlein. We will study some of the second-order nonlinear ODEs, especially those that exhibit limit cycles, and systems of nonlinear ODEs that these functions are giving solutions to. 展开更多
关键词 Non-Elementary functions second-Order Nonlinear Autonomous ODE
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On Two New Groups of Non-Elementary Functions That Are Giving Solutions to Some Second-Order Nonlinear Autonomous ODEs
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作者 Magne Stensland 《Journal of Applied Mathematics and Physics》 2022年第3期703-713,共11页
In this paper, we define a group of solutions x(t) that are sine and cosine to the upper limit of integration in a non-elementary integral that can be arbitrary. We will also define a group of solutions x(t) that are ... In this paper, we define a group of solutions x(t) that are sine and cosine to the upper limit of integration in a non-elementary integral that can be arbitrary. We will also define a group of solutions x(t) that are equal to the amplitude. This is a generalized amplitude function. We are using Abel’s methods, described by Armitage and Eberlein. And finally, we define an exponential function whose exponent is the product of a complex number and the upper limit of integration in a non-elementary integral that can be arbitrary. At least three groups of non-elementary functions are special cases of this complex function. 展开更多
关键词 Non-Elementary functions second-Order Nonlinear Autonomous ODE
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Six New Sets of the Non-Elementary Jef-Family-Functions that Are Giving Solutions to Some Second-Order Nonlinear Autonomous ODEs
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作者 Magne Stensland 《Journal of Applied Mathematics and Physics》 2023年第4期1077-1097,共21页
In this paper, we define some new sets of non-elementary functions in a group of solutions x(t) that are sine and cosine to the upper limit of integration in a non-elementary integral that can be arbitrary. We are usi... In this paper, we define some new sets of non-elementary functions in a group of solutions x(t) that are sine and cosine to the upper limit of integration in a non-elementary integral that can be arbitrary. We are using Abel’s methods, described by Armitage and Eberlein. The key is to start with a non-elementary integral function, differentiating and inverting, and then define a set of three functions that belong together. Differentiating these functions twice gives second-order nonlinear ODEs that have the defined set of functions as solutions. We will study some of the second-order nonlinear ODEs, especially those that exhibit limit cycles. Using the methods described in this paper, it is possible to define many other sets of non-elementary functions that are giving solutions to some second-order nonlinear autonomous ODEs. 展开更多
关键词 Non-Elementary functions second-Order Nonlinear Autonomous ODE Limit Cycle
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双偶氮苯-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子的二阶非线性光学性质 被引量:1
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作者 张宇红 李博 +4 位作者 陈自然 李渊 徐友辉 张莉萍 何旭东 《原子与分子物理学报》 CAS 北大核心 2025年第2期15-23,共9页
使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与... 使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与电子吸收光谱,采用有效场FF方法研究了二阶非线性光学性质(NLO).研究结果表明,26个噻蒽四酮类衍生物分子的能隙在1.33—2.02 eV范围,归属于有机半导体;最低能量吸收峰波长在601.8~609.5nm范围;在增大分子的二阶非线性光学系数β_(μ)(或β_(0))值方面,含相同偶氮苯基团或含不同偶氮苯基团分别引入到二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮分子两侧的2,10位优于2,9位,在2,10位分别端接含推、拉基团的偶氮苯优于含相同给电子基团的偶氮苯.在偶氮苯苯环对位分别端接强吸电子基(-NO_(2))与强供电子基(如-N(CH_(3))_(2)、-N(Ph)_(3)、-N-苯基咔唑等)可增强体系的二阶非线性光学性能,获得性能良好的非线性光学材料. 展开更多
关键词 双偶氮 二苯并[b i]噻蒽-[2 3-b]苯-5 7 12 14-四酮 密度泛函理论 电子吸收光谱 二阶非线性光学性质
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Subspaces for weak mild solutions of the second order abstract differential equation
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作者 王梅英 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期313-316,共4页
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
关键词 second order abstract differential equation polynomially bounded solution cosine operator function
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