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C_0-Semigroup Method of the Density Evolution Equation for M/M/∞ Model
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作者 SHI Ding hua, XIONG Yong, XU Hong College of Sciences, Shanghai University, Shanghai 200436, China 《Journal of Shanghai University(English Edition)》 CAS 2001年第4期265-268,共4页
In this paper, the existence, uniqueness, and asymptotic behavior of the solution of the density evolution equation for M/M/∞ model was studied by the semigroup theory of linear operators.
关键词 M/M/∞ model density evolution equation c 0-semigroup
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Exponential Stabilization for C_0-Semigroups Under Compact Perturbation
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作者 刘立新 《Journal of Southwest Jiaotong University(English Edition)》 2008年第3期295-297,共3页
It is proved that a system under compact perturbation cannot be uniformly exponentially stable for an isometric C0-semigroup or a C0-group with polynomial growth for negative time in a Banach space. The results extend... It is proved that a system under compact perturbation cannot be uniformly exponentially stable for an isometric C0-semigroup or a C0-group with polynomial growth for negative time in a Banach space. The results extend and improve the corresponding results of previous literature. 展开更多
关键词 compact perturbation Exponential stabilization Isometric c0-semigroup Polynomial growth for negative time
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CL-20/HMX无规作用及共晶作用的理论计算 被引量:5
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作者 陶俊 王晓峰 +5 位作者 赵省向 韩仲熙 李文红 王彩玲 黄亚峰 方伟 《火炸药学报》 EI CAS CSCD 北大核心 2017年第4期50-55,共6页
为了对比六硝基六氮杂异戊兹烷(CL-20)/环四亚甲基四硝铵(HMX)炸药分子间的无规作用及共晶作用,基于密度泛函理论(DFT),在B3LYP方法上使用6-311++G(d,p)基组优化得到了4种CL-20/HMX无规构型(Ⅰ、Ⅱ、Ⅲ和Ⅳ),对4种无规构型的几何结构、... 为了对比六硝基六氮杂异戊兹烷(CL-20)/环四亚甲基四硝铵(HMX)炸药分子间的无规作用及共晶作用,基于密度泛函理论(DFT),在B3LYP方法上使用6-311++G(d,p)基组优化得到了4种CL-20/HMX无规构型(Ⅰ、Ⅱ、Ⅲ和Ⅳ),对4种无规构型的几何结构、静电势、能量及电子密度拓扑进行了分析;利用分子动力学方法计算了共晶结构中H原子和O原子的径向分布函数;计算了不同摩尔比CL-20/HMX共晶的密度及爆速。结果表明,4种CL-20/HMX的无规构型存在氢键相互作用,氢键键长在0.274 2~0.296 4nm之间;4种无规构型的稳定性排序为:Ⅳ>Ⅲ>Ⅱ>Ⅰ,构型的稳定性主要取决于氢键的数量和键长;4种无规构型在键临界点BCP处的电子密度ρ(r)大小排序为:Ⅳ>Ⅲ>Ⅱ>Ⅰ,CL-20和HMX分子之间不仅存在H…O以及H…N形式的氢键相互作用,还存在N…O和C…O形式的范德华作用;共晶结构中CL-20与HMX的相互作用主要有氢键和强范德华力,氢键键长为0.22nm;CL-20/HMX共晶(摩尔比2∶1)的理论密度为2.003g/cm^3,理论爆速为9 608m/s。 展开更多
关键词 六硝基六氮杂异戊兹烷 cL-20 环四甲基四硝铵 HMX 共晶 分子间作用 密度泛函理论
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C^0型高阶锯齿理论及复合材料厚梁热应力分析 被引量:4
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作者 任晓辉 陈万吉 《计算力学学报》 CAS CSCD 北大核心 2015年第1期77-82,共6页
基于已有锯齿理论构造单元时,需使用满足单元间C1连续的插值函数,难于构造多节点高阶单元,而且精度较低。针对已有锯齿理论存在的问题,本文首先发展了C0型锯齿理论。通过虚位移原理推导出在热载荷作用下复合材料梁的平衡方程,并给出了... 基于已有锯齿理论构造单元时,需使用满足单元间C1连续的插值函数,难于构造多节点高阶单元,而且精度较低。针对已有锯齿理论存在的问题,本文首先发展了C0型锯齿理论。通过虚位移原理推导出在热载荷作用下复合材料梁的平衡方程,并给出了简支复合材料层合梁解析解。基于发展的锯齿理论分析了复合材料夹层梁和层合梁热膨胀问题,并与其他理论结果对比。数值结果表明,发展的C0型锯齿理论能克服已有锯齿理论的难题。 展开更多
关键词 c^0型锯齿理论 横法向应变 横向位移导数 层合梁 热应力
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应变梯度理论有限元:C^(0-1)分片检验及其变分基础 被引量:12
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作者 陈万吉 《大连理工大学学报》 EI CAS CSCD 北大核心 2004年第4期474-477,共4页
基于细观有限元弹性应变梯度理论,首次提出应变梯度有限元的C0-1分片检验条件及其变分基础和一种构造应变梯度单元的方法.与常规的C0分片检验和C1分片检验不同,C0-1分片检验要求检验函数为满足平衡方程的二次函数,并同时通过线性平面应... 基于细观有限元弹性应变梯度理论,首次提出应变梯度有限元的C0-1分片检验条件及其变分基础和一种构造应变梯度单元的方法.与常规的C0分片检验和C1分片检验不同,C0-1分片检验要求检验函数为满足平衡方程的二次函数,并同时通过线性平面应力C0分片检验和应变梯度常曲率的C1分片检验.进一步提出一个平面18-DOF三角形应变梯度单元(RCT9+RT9),算例表明该单元通过C0-1分片检验,无伪零能模式,并有较高的精度. 展开更多
关键词 弹性应变梯度理论 平面18-DOF 三角形应变梯度单元 c^0-1分片检验 孔边应力
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富勒烯C_(70)吸附氧原子的密度泛函理论研究 被引量:2
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作者 焦志峰 《化学研究与应用》 CAS CSCD 北大核心 2012年第10期1605-1608,共4页
在密度泛函B3LYP理论下,用6-31G*基函数对富勒烯C70吸附氧原子进行了理论研究。讨论了其几何结构、电子属性、反应能、电离势和电子亲和势。计算结果表明:一个氧原子吸附在C70赤道带上形成具有开环轮烯结构的e,e-C70O是最稳定的。与基态... 在密度泛函B3LYP理论下,用6-31G*基函数对富勒烯C70吸附氧原子进行了理论研究。讨论了其几何结构、电子属性、反应能、电离势和电子亲和势。计算结果表明:一个氧原子吸附在C70赤道带上形成具有开环轮烯结构的e,e-C70O是最稳定的。与基态的C70O相比,C70O35具有较大的HOMO-LUMO能隙,较高的电离势和较低的电子亲和势,因此C70O35是稳定的分子。 展开更多
关键词 密度泛函理论 富勒烯c70 吸附氧
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An advanced higher-order theory for laminated composite plates with general lamination angles
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作者 Zhen Wu Hong Zhu Wan-Ji Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期720-729,共10页
This paper proposes a higher-order shear deformation theory to predict the bending response of the laminated composite and sandwich plates with general lamination configurations.The proposed theory a priori satisfies ... This paper proposes a higher-order shear deformation theory to predict the bending response of the laminated composite and sandwich plates with general lamination configurations.The proposed theory a priori satisfies the continuity conditions of transverse shear stresses at interfaces.Moreover,the number of unknown variables is independent of the number of layers.The first derivatives of transverse displacements have been taken out from the inplane displacement fields,so that the C 0 shape functions are only required during its finite element implementation.Due to C 0 continuity requirements,the proposed model can be conveniently extended for implementation in commercial finite element codes.To verify the proposed theory,the fournode C 0 quadrilateral element is employed for the interpolation of all the displacement parameters defined at each nodal point on the composite plate.Numerical results show that following the proposed theory,simple C 0 finite elements could accurately predict the interlaminar stresses of laminated composite and sandwich plates directly from a constitutive equation,which has caused difficulty for the other global higher order theories. 展开更多
关键词 Laminated and sandwich composites Higherorder theory c 0 continuity requirement Transverse shear stress
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Reliability Analysis of a Cold Standby Repairable System with Repairman Extra Work 被引量:13
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作者 ZHANG Xin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第5期1015-1032,共18页
This paper deals with a cold standby repairman who can do extra work in idle time. The repairable system with two identical units and one authors are devoted to studying the unique existence and exponential stability ... This paper deals with a cold standby repairman who can do extra work in idle time. The repairable system with two identical units and one authors are devoted to studying the unique existence and exponential stability of the system solution. C0-semigroup theory is used to prove the existence of a unique nonnegative time-dependent solution of the system. Then by using the theory of resolvent positive operator, the authors derive that dynamic solution of the system exponentially converges to its steady-state one which is the eigenfunction corresponding to eigenvalue 0 of the system operator. Some reliability indices of the system are discussed with a different method from traditional one. The authors also make a profit analysis to determine the optimal service time outside the system to maximize the system profit. 展开更多
关键词 c0-semigroup exponential stability repairable system resolvent positive operator.
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DIFFERENTIAL VARIATIONAL INEQUALITIES IN INFINITE BANACH SPACES 被引量:7
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作者 刘振海 曾生达 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期26-32,共7页
In this paper,we consider a new differential variational inequality(DVI,for short)which is composed of an evolution equation and a variational inequality in infinite Banach spaces.This kind of problems may be regard... In this paper,we consider a new differential variational inequality(DVI,for short)which is composed of an evolution equation and a variational inequality in infinite Banach spaces.This kind of problems may be regarded as a special feedback control problem.Based on the Browder's theorem and the optimal control theory,we show the existence of solutions to the mentioned problem. 展开更多
关键词 differential variational inequality c0-semigroup monotone operator existcnceof solutions
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Asymptotic Stability of the Dynamic Solution of an N-Unit Series System with Finite Number of Vacations 被引量:1
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作者 Abdugeni Osman Abdukerim Haji Askar Ablimit 《Journal of Applied Mathematics and Physics》 2018年第11期2202-2218,共17页
We investigate an N-unit series system with finite number of vacations. By analyzing the spectral distribution of the system operator and taking into account the irreducibility of the semigroup generated by the system... We investigate an N-unit series system with finite number of vacations. By analyzing the spectral distribution of the system operator and taking into account the irreducibility of the semigroup generated by the system operator we prove that the dynamic solution converges strongly to the steady state solution. Thus we obtain asymptotic stability of the dynamic solution of the system. 展开更多
关键词 N-Unit Series System c0-semigroup IRREDUcIBILITY ASYMPTOTIc Stability
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Approximate controllability of infinite dimensional linear systems in nonreflexive state spaces
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作者 Xin YU Chao XU 《控制理论与应用(英文版)》 EI 2005年第2期186-188,共3页
This paper deals with the problem of approximate controllability of infinite dimensional linear systems in nonreflexive state spaces. A necessary and sufficient condition for approximate controllability via L^p([0, T... This paper deals with the problem of approximate controllability of infinite dimensional linear systems in nonreflexive state spaces. A necessary and sufficient condition for approximate controllability via L^p([0, T], U), 1≤p〈∞ is obtained,where L^p( [0, T], U) is the control function space. 展开更多
关键词 Approximate controllability Exact controllability Reflexive space c0-semigroup
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Asymptotic Stability of a Series-Parallel Repairable System Consisting of Three-Unit with Multiple Vacations of a Repairman
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作者 Tursunjan Keyim Abdukerim Haji 《Journal of Applied Mathematics and Physics》 2017年第1期185-193,共9页
We study a series-parallel repairable system consisting of three units with multiple vacations of a repairman. We first show that all points on the imaginary axis except zero belong to the resolvent set of the operato... We study a series-parallel repairable system consisting of three units with multiple vacations of a repairman. We first show that all points on the imaginary axis except zero belong to the resolvent set of the operator and zero is an eigenvalue of the operator, and then we prove that the semigroup generated by the operator is irreducible. By combining these results with our previous result we deduce that the dynamic solution of the system converges strongly to its steady-state solution. Thus we obtain asymptotic stability of the dynamic solution of the system. 展开更多
关键词 SERIES-PARALLEL REPAIRABLE System c0-semigroup IRREDUcIBILITY Asymptotic Stability
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Asymptotic Stability of Gaver’s Parallel System Attended by a Cold Standby Unit and a Repairman with Multiple Vacations
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作者 Abdukerim Haji 《World Journal of Engineering and Technology》 2015年第3期277-283,共7页
We investigate Gaver’s parallel system attended by a cold standby unit and a repairman with multiple vacations. By analysing the spectral distribution of the system operator and taking into account the irreducibility... We investigate Gaver’s parallel system attended by a cold standby unit and a repairman with multiple vacations. By analysing the spectral distribution of the system operator and taking into account the irreducibility of the semigroup generated by the system operator we prove that the dynamic solution converges strongly to the steady state solution. Thus we obtain asymptotic stability of the dynamic solution of the system. 展开更多
关键词 Gaver’s Parallel Pystem c0-semigroup IRREDUcIBILITY ASYMPTOTIc Stability
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Well-Posedness of Gaver’s Parallel System Attended by a Cold Standby Unit and a Repairman with Multiple Vacations
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作者 Abdukerim Haji Bilikiz Yunus 《Journal of Applied Mathematics and Physics》 2015年第7期821-827,共7页
We investigate Gaver’s parallel system attended by a cold standby unit and a repairman with multiple vacations. By using C0-semigroup theory of linear operators in the functional analysis, we prove well-posedness and... We investigate Gaver’s parallel system attended by a cold standby unit and a repairman with multiple vacations. By using C0-semigroup theory of linear operators in the functional analysis, we prove well-posedness and the existence of the unique positive dynamic solution of the system. 展开更多
关键词 Gaver’s PARALLEL Pystem c0-semigroup WELL-POSEDNESS
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Observer for Linear Distributed-Parameter Systems with Application to Isothermal Plug-Flow Reactor
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作者 Nadia Barje Mohamed Elarbi Achhab Vincent Wertz 《Intelligent Control and Automation》 2013年第4期379-384,共6页
This paper presents a conception of an exponential observer for a class of linear distributed-parameter systems (DPSs), in which the dynamics are partially unknown. The given distributed-parameter observer ensures asy... This paper presents a conception of an exponential observer for a class of linear distributed-parameter systems (DPSs), in which the dynamics are partially unknown. The given distributed-parameter observer ensures asymptotic state estimator with exponentially decay error, based on the theory of C0-semigroups in a Hilbert space. The theoretical observer developed is applied to a chemical tubular reactor, namely the isothermal Plug-Flow reactor basic dynamical model for which measurements are available at the reactor output only. The process is described by Partial differential equations with unknown initial states. For this application, performance issues are illustrated in a simulation study. 展开更多
关键词 Distributed-Parameter SYSTEMS c0-semigroup EXPONENTIAL Observers PERTURBED SYSTEMS TUBULAR Reactor
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Complex Symmetric C0-semigroups on A^2(C+) 被引量:1
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作者 Kai Kai HAN Mao Fa WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2020年第10期1171-1182,共12页
In this paper,we study complex symmetric C0-semigroups on the Bergman space A^2(C+) of the right half-plane C+.In contrast to the classical case,we prove that the only involutive composition operator on A^2(C+) is the... In this paper,we study complex symmetric C0-semigroups on the Bergman space A^2(C+) of the right half-plane C+.In contrast to the classical case,we prove that the only involutive composition operator on A^2(C+) is the identity operator,and the class of J-symmetric composition operators does not coincide with the class of normal composition operators.In addition,we divide semigroups{φt}of linear fractional self-maps of C+into two classes.We show that the associated composition operator semigroup{Tt}is strongly continuous and identify its infinitesimal generator.As an application,we characterize Jσ-symmetric C0-semigroups of composition operators on A^2(C+). 展开更多
关键词 c0-semigroup Bergman space composition operator complex symmetry
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Dynamic Analysis of the Multi-state Reliability System with Priority Repair Discipline
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作者 Aihemaitijiang YUMAIER Ehmet KASIM 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2024年第3期665-694,共30页
This paper considers a multi-state repairable system that is composed of two classes of components,one of which has a priority for repair.First,we investigate the well-posedenss of the system by applying the operator ... This paper considers a multi-state repairable system that is composed of two classes of components,one of which has a priority for repair.First,we investigate the well-posedenss of the system by applying the operator semigroup theory.Then,using Greiner’s idea and the spectral properties of the corresponding operator,we obtain that the time-dependent solution of the system converges strongly to its steady-state solution. 展开更多
关键词 multi-state system c0-semigroup Dirichlet operator WELL-POSEDNESS asymptotic behavior
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关于两种二阶应变梯度理论 被引量:2
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作者 赵杰 陈万吉 冀宾 《力学学报》 EI CSCD 北大核心 2010年第1期138-145,共8页
对常见的两种应变梯度理论进行了深入的理论分析,比较了它们在公式推导、能量表达、物理解释和应用领域方面的差异.选择钢筋拉拔弹性阶段和超薄悬臂梁受压弯曲两个典型的算例,采用可以通过C^(0-1)分片检验的18自由度应变梯度平面三角形... 对常见的两种应变梯度理论进行了深入的理论分析,比较了它们在公式推导、能量表达、物理解释和应用领域方面的差异.选择钢筋拉拔弹性阶段和超薄悬臂梁受压弯曲两个典型的算例,采用可以通过C^(0-1)分片检验的18自由度应变梯度平面三角形单元和轴对称三角形单元,通过数值计算比较了两种理论在描述细观力学性能方面的差异. 展开更多
关键词 应变梯度理论 材料长度参数 有限元 c1弱连续 c0-1分片检验
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轴对称弹性应变梯度理论公式推导及有限元实现 被引量:1
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作者 赵杰 陈万吉 冀宾 《计算力学学报》 EI CAS CSCD 北大核心 2009年第2期209-214,共6页
用张量运算推导了弹性应变梯度轴对称问题的基本公式。建立了应变梯度轴对称不协调元的弱连续条件,进一步建立了满足弱连续条件的应变梯度轴对称18-DOF三角形单元(BCIZ+ART9),其中BCIZ满足线性应变C0连续,用于计算应变ε;ART9满足常曲... 用张量运算推导了弹性应变梯度轴对称问题的基本公式。建立了应变梯度轴对称不协调元的弱连续条件,进一步建立了满足弱连续条件的应变梯度轴对称18-DOF三角形单元(BCIZ+ART9),其中BCIZ满足线性应变C0连续,用于计算应变ε;ART9满足常曲率C1弱连续,用于计算应变梯度η。数值结果表明该单元通过C0-1分片检验并能体现材料的尺度效应。 展开更多
关键词 应变梯度理论 c^1弱连续 轴对称单元 c^0-1分片检验
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带有时滞和热扩散效应的Timoshenko系统的适定性
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作者 秦玉明 韩宁 《Chinese Quarterly Journal of Mathematics》 2022年第1期1-9,共9页
In this paper,we study the well-posedness for the thermoelastic Timoshenko system with a constant delay and mass diffusion effects.Heat and mass exchange with the environment during thermodiffusion in Timoshenko beam.... In this paper,we study the well-posedness for the thermoelastic Timoshenko system with a constant delay and mass diffusion effects.Heat and mass exchange with the environment during thermodiffusion in Timoshenko beam.The C_(0)-semigroup theory will be used to prove the well-posedness of the considered problem. 展开更多
关键词 Timoshenko system WELL-POSEDNESS Delay c0-semigroup theory
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