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混凝土坝温控三维仿真敏感分析及其凝聚方程 被引量:2
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作者 侯朝胜 赵代深 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2001年第5期605-610,共6页
采用全过程仿真粘弹性空间有限单元法 ,对混凝土坝典型浇筑块进行了温控敏感分析 ,得出温控因素 (浇筑温度、间歇天数、开浇日期、浇筑层厚度 )对浇筑块强约束区最大拉应力的影响 .在此基础上采用回归分析和拉格朗日插值方法得出多维数... 采用全过程仿真粘弹性空间有限单元法 ,对混凝土坝典型浇筑块进行了温控敏感分析 ,得出温控因素 (浇筑温度、间歇天数、开浇日期、浇筑层厚度 )对浇筑块强约束区最大拉应力的影响 .在此基础上采用回归分析和拉格朗日插值方法得出多维数值空间最大拉应力凝聚方程 ,可用于推算不同施工方案的浇筑块强约束区的最大拉应力 . 展开更多
关键词 全过程仿真 三维有限元 混凝土坝 温度控制 敏感分析 凝聚方程 最大拉应力
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混凝土坝温控因素敏感分析及其在多维空间的凝聚方程 被引量:1
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作者 赵代深 《水利水电技术》 CSCD 北大核心 2001年第11期14-19,共6页
采用全过程仿真粘弹性空间有限单元法,对9种温控因素进行了敏感分析,得出温控因素变化对浇筑块强约束区中心最高温度、最大基础温差和最大拉应力的影响.在敏感分析的基础上,采用回归分析和拉格郎日插值方法在温控因素多维空间建立了凝... 采用全过程仿真粘弹性空间有限单元法,对9种温控因素进行了敏感分析,得出温控因素变化对浇筑块强约束区中心最高温度、最大基础温差和最大拉应力的影响.在敏感分析的基础上,采用回归分析和拉格郎日插值方法在温控因素多维空间建立了凝聚方程,利用凝聚方程可计算任意施工条件下的最大基础温差和最大拉应力. 展开更多
关键词 混凝土坝 温度控制 敏感分析 凝聚方程 全过程仿真 粘弹性 空间 有限单元法 浇筑 温控因素 多维空间
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一类次临界Bose-Einstein凝聚型方程组的渐近收敛行为和相位分离 被引量:1
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作者 张晶 《数学物理学报(A辑)》 CSCD 北大核心 2019年第3期441-450,共10页
该文利用变分法和椭圆方程理论研究有界光滑区域上次临界Bose-Einstein凝聚型方程组耦合系数趋于负无穷时解的极限产生的相位分离现象.
关键词 Bose-Einstein凝聚方程 次临界指数 变分法 相位分离
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高温蠕变空位凝聚区的凝聚扩散 被引量:2
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作者 张平 彭凡 +1 位作者 马石城 刘忠 《固体力学学报》 CAS CSCD 北大核心 1997年第3期195-203,共9页
讨论局域凝聚扩散现象,导出局域凝聚-扩散方程并给出解的存在唯一性定理.对凝聚-扩散方程的稳定性的分析获得结论,定态解的稳定性由凝聚函数控制,并导出一元系统和二元系统的失稳临界条件表达式.
关键词 高温 蠕变 空位凝聚 稳定性 凝聚扩散方程
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局部凸空间中凸幂凝聚算子的不动点定理及其应用(英文) 被引量:3
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作者 史红波 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第9期1-5,共5页
首先给出了局部凸空间中一类新的算子——凸幂凝聚算子的定义,推广了Banach中的凝聚算子,并获得了这类凸幂凝聚算子的一个不动点定理.作为应用,本文建立了一类半线性发展方程的解的存在性结果.
关键词 局部凸空间 凸幂凝聚算子:不动点定理:半线性发展方程
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(B)空间中的凝聚映像方程 被引量:7
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作者 杨书郎 《应用数学学报》 CSCD 北大核心 1990年第3期351-357,共7页
如所周知,有关(B)空间X中的映像方程 θ=T_1(x)-x (1)的研究,是有重要的理论与应用价值的.例如,在处理一些理论与实际问题的时候,常可把它们纳入有关(1)的解或(相应映像的)本征元等问题的框架之中. 考虑方程(1).文中考虑的映像T_1:C→X... 如所周知,有关(B)空间X中的映像方程 θ=T_1(x)-x (1)的研究,是有重要的理论与应用价值的.例如,在处理一些理论与实际问题的时候,常可把它们纳入有关(1)的解或(相应映像的)本征元等问题的框架之中. 考虑方程(1).文中考虑的映像T_1:C→X是个凝聚映像.又,C是X的子集. 展开更多
关键词 (B)空间 凝聚映像方程 fp-凝聚同伦
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基于凝聚函数的拟牛顿算法求解绝对值方程 被引量:27
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作者 雍龙泉 拓守恒 《系统科学与数学》 CSCD 北大核心 2012年第11期1427-1436,共10页
绝对值方程Ax-|x|=b是一个不可微的NP-hard问题.在假设矩阵A的奇异值大于1(这里矩阵A的奇异值定义为矩阵A^TA特征值的非负平方根)时,给出了求解绝对值方程一个新的光滑化算法.通过引入一种凝聚函数对绝对值方程进行光滑化处理,得到一个... 绝对值方程Ax-|x|=b是一个不可微的NP-hard问题.在假设矩阵A的奇异值大于1(这里矩阵A的奇异值定义为矩阵A^TA特征值的非负平方根)时,给出了求解绝对值方程一个新的光滑化算法.通过引入一种凝聚函数对绝对值方程进行光滑化处理,得到一个非线性方程组;再引入适当的目标函数,进而把绝对值方程化为无约束优化问题,然后利用拟牛顿算法对其进行求解.数值实验结果表明了该方法的正确性和有效性. 展开更多
关键词 绝对值方程 拟牛顿算法 凝聚函数
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Weak Nonlinear Matter Waves in a Trapped Spin-1 Condensates
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作者 蔡宏强 杨树荣 薛具奎 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期583-588,共6页
The dynamics of the weak non//near matter sofitary waves in a spin-1 condensates with harmonic external potential are investigated analytically by a perturbation method. It is shown that, in the small amplitude limit,... The dynamics of the weak non//near matter sofitary waves in a spin-1 condensates with harmonic external potential are investigated analytically by a perturbation method. It is shown that, in the small amplitude limit, the dynamics of the solitary waves are governed by a variable-coetficient Korteweg-de Vries (KdV) equation. The reduction to the (KdV) equation may be useful to understand the dynamics of nonlinear matter waves in spinor BECs. The analytical expressions for the evolution of soliton show that the small-amplitude vector solitons of the mixed types perform harmonic oscillations in the presence of the trap. Furthermore, the emitted radiation profiles and the soliton oscillation frequency are also obtained. 展开更多
关键词 spin-1 condensate weak nonlinear matter solitary wave variable-coefficient KdV equation
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Stability of Two-Component Bose-Einstein Condensates in Bessel Optical Lattices
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作者 CHEN Hai-Jun LI Hao-Cai XUE Ju-Kui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1519-1526,共8页
The stability of the ground state of two-component Bose-Einstein condensates (BEGs) loaded into the central well of an axially symmetric Bessel lattices (BLs) potential with attractive or repulsive atoms interacti... The stability of the ground state of two-component Bose-Einstein condensates (BEGs) loaded into the central well of an axially symmetric Bessel lattices (BLs) potential with attractive or repulsive atoms interactions is studied using the time-dependent Gross-Pitaevskii equation (GPE). By using the variational method, we find that stable ground state of two-component BEGs can exist in BLs. The BLs's depth and the intra-species atom interaction play an important role in the stability of ground state. The collapse of two-component BEGs in BLs is also studied and a collapse condition for trapped two-component BEGs is obtained. It is shown that the two-component BEGs exhibit rich collapse dynamics. That is, the two-component BEGs can collapse in the system with both intra- and inter-attractive, or with intra-attractive and inter-repulsive, or with intra-repulsive and inter-attractive atom interactions. Furthermore, the control of the collapse of the two-component BEGs in BLs is discussed in detail. The stability diagram of the ground state in parameter space is obtained. The results show that the collapse of two-component BEGs can be controlled by temporal modulation of the atom interaction. 展开更多
关键词 two-component Bose-Einstein condensates Gross-Pitaevskii equation Bessel optical lattice ground state
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Kinetic Behaviour of the Aggregation—Annihilation Process of Two—Species—Group System
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作者 LINZhen-Quan KEJian-Hong WANgXiang-Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第5期635-640,共6页
The kinetic behavior of an aggregation-annihilation system with two species groups is studied in this paper.We propose that an aggregation reaction occurs only between the same species and an irreversible joint annihi... The kinetic behavior of an aggregation-annihilation system with two species groups is studied in this paper.We propose that an aggregation reaction occurs only between the same species and an irreversible joint annihilation reaction occurs only between the two species belonging to distinct groups. Based on the mean-field theory, we investigate the rate equations of the process with constant reaction rates and obtain the asymptotic descriptions of the cluster-mass distributions for the symmetrical cases. We find that the cluster-mass distribution of each species obeys a standard scaling description in certain cases. Meanwhile, breakdown of the standard scaling description is also found for the distribution in some special cases and the cluster-mass distribution comes in a peculiar scaling regime. The evolutionbehaviour of the system depends crucially on the reaction rates and the ratio of initial concentrations between the two groups. Moreover, the species numbers of the two groups also play important roles in the properties of the cluster distributions. 展开更多
关键词 kinetic behaviour aggregation-annihilation process scaling law rate equation
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On a Singular Solution in Higgs Field (Ⅲ): Condensates and Representation of Certain f0 Mesons' Masses
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作者 Kazuyoshi Kitazawa 《Journal of Physical Science and Application》 2013年第2期115-122,共8页
Recently the mass and the basic structure of SM Higgs boson (H^0) have been discussed by the author with obtaining asymptotic solution for the equation of motion of nonlinear Klein-Gordon type partial differential e... Recently the mass and the basic structure of SM Higgs boson (H^0) have been discussed by the author with obtaining asymptotic solution for the equation of motion of nonlinear Klein-Gordon type partial differential equation. In this paper, we will treat with above in mind: masses of glueball (GB) of ground state and of certain fo mesons, ur, Higgs boson (ur-H^0) which will consist of a number of GBs and/or fo above for respective fullerene structure, a representation of these fo mesons' masses by masses of n octet and GB, and transformation of ur-H^0 into H^0. 展开更多
关键词 Higgs boson mass GLUEBALL GLUON f0 meson Bethe-Salpeter equation.
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外电场对荷电颗粒静电凝聚的影响 被引量:14
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作者 张向荣 王连泽 朱克勤 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第8期1107-1109,共3页
为了定量地分析外电场对荷电颗粒静电凝聚的影响,在理论分析和数值模拟的基础上,求解荷电颗粒凝聚的数量平衡方程,分析比较外电场存在与否时,颗粒数量浓度的变化关系。结果表明:外电场促进荷电颗粒间的凝聚;对于初始对称双极荷电颗粒,... 为了定量地分析外电场对荷电颗粒静电凝聚的影响,在理论分析和数值模拟的基础上,求解荷电颗粒凝聚的数量平衡方程,分析比较外电场存在与否时,颗粒数量浓度的变化关系。结果表明:外电场促进荷电颗粒间的凝聚;对于初始对称双极荷电颗粒,外电场不改变颗粒初始电荷分布的对称性,并且带任意电荷量的颗粒的数量浓度随凝聚时间单调减少;对于初始非对称双极荷电以及单极荷电颗粒,其数量浓度并非都随凝聚时间单调减少。 展开更多
关键词 颗粒凝聚方程 荷电颗粒 凝聚系数 外电场
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Soliton Solutions in Three-Component Bose-Einstein Condensates
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作者 ZHANG Xiao-Fei XIE Chong-Wei WANG Shi-En 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1063-1066,共4页
We obtain soliton and plane wave solutions for the coupled nonlinear Schrotinger equations, which describe the dynamics of the three-component Bose-Einstein condensates by using the Hirota method. Meanwhile we find th... We obtain soliton and plane wave solutions for the coupled nonlinear Schrotinger equations, which describe the dynamics of the three-component Bose-Einstein condensates by using the Hirota method. Meanwhile we find that the system which has attractive atomic interaction will only possess a shape changing (inelastic) collision property due to intensity redistribution in the absence of the spin-exchange interaction. As a discussed example, we investigate the one-soliton, two-soliton solutions and collisional effects between bright two-soliotn solution, which lead to the intensity redistribu tion. 展开更多
关键词 Bose-Einstein condensate SOLITON
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Phase of Two-Component Bose-Einstein Condensates with a Coupling Drive
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作者 YU Zhao-Xian JIN Shuo +1 位作者 JIAO Zhi-Yong WANG Ji-Suo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5期801-804,共4页
By using the invariant theory, we study the phases of two-component Bose-Einstein condensates with a coupling drive under the case that the strength of the interatomic interaction in each condensate equals the intersp... By using the invariant theory, we study the phases of two-component Bose-Einstein condensates with a coupling drive under the case that the strength of the interatomic interaction in each condensate equals the interspecies interaction. The dynamical and geometric phases are presented respectively. The Aharonov-Anandan phase is also obtained under the cyclical evolution. 展开更多
关键词 Bose-Einstein condensation
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双极荷电颗粒在外加交变电场中的静电凝聚 被引量:3
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作者 谭百贺 王连泽 吴子牛 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第2期301-304,共4页
为了定量分析外加交变电场对双极荷电颗粒静电凝聚的影响,基于双极荷电颗粒在交变电场中的静电凝聚系数公式,利用数值计算的方法求解了荷电颗粒凝聚的数量平衡方程,得到了不同时刻颗粒数量浓度、颗粒带电量和颗粒粒径的关系曲线,比较了... 为了定量分析外加交变电场对双极荷电颗粒静电凝聚的影响,基于双极荷电颗粒在交变电场中的静电凝聚系数公式,利用数值计算的方法求解了荷电颗粒凝聚的数量平衡方程,得到了不同时刻颗粒数量浓度、颗粒带电量和颗粒粒径的关系曲线,比较了外电场存在与否时颗粒数量浓度的变化。结果表明:对于初始单弥散度带任意电荷量的颗粒,其数量浓度随凝聚时间单调减少;外加交变电场能够有效地促进双极荷电颗粒间的凝聚;颗粒上所带的电荷量越大,凝聚效果越明显。 展开更多
关键词 颗粒凝聚方程 荷电颗粒 凝聚系数 交变电场
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关于一类非线性方程的非零解与固有元问题
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作者 张碧霞 《福州大学学报(自然科学版)》 CAS CSCD 2003年第1期9-12,共4页
fp -同伦方法 ,通过特殊的技巧———构造若干特定的泛函 ,在边界条件 (MS ; C ,a)和 (CS ; D ,b )等的支持下 ,研究了Banach空间中集值凝聚方程的非零解与固有元的若干问题 .
关键词 非线性方程 非零解 固有元 BANACH空间 集值凝聚方程 fp-同伦方法 边界条件
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Tunneling and Self-Trapping of Superfluid Fermi Gases in BCS-BEC Crossover
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作者 周昱 王颖 +1 位作者 罗文琛 马晓栋 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第2期188-194,共7页
We investigate tunneling and self-trapping of superfluid Fermi gases under a two-mode ansatz in different regimes of the crossover from Bardeen-Cooper-Schrieffer (BCS) superfluid to Bose-Einstein condensates (BEC)... We investigate tunneling and self-trapping of superfluid Fermi gases under a two-mode ansatz in different regimes of the crossover from Bardeen-Cooper-Schrieffer (BCS) superfluid to Bose-Einstein condensates (BEC). Starting from a generalized equation of state, we derive the coupled equations of relative atom-pair number and relative phase about superfluid Fermi gases in a double-well system and then classify the different oscillation behaviors by the tunneling strength and interactions between atoms. Tunneling and self-trapping behaviors are considered in the whole BCS-BEC crossover in the ease of a symmetric double-well potential. We show that the nonlinear interaction between atoms makes the self-trapping more easily realized in BCS regime than in the BEC regime and stability analysis is also given. 展开更多
关键词 BCS-BEC crossover Josephson effect macroscopic quantum self-trapping
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Bose-Einstein Condensate in a Linear Trap with a Dimple Potential
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作者 Haydar Uncu Devrim Tarhan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第5期629-637,共9页
We study Bose-Einstein condensation in a linear trap with a dimple potential where we model dimple potentials by Dirac δ function. Attractive and repulsive dimple potentials are taken into account. This model allows ... We study Bose-Einstein condensation in a linear trap with a dimple potential where we model dimple potentials by Dirac δ function. Attractive and repulsive dimple potentials are taken into account. This model allows simple, explicit numerical and analytical investigations of noninteracting gases. Thus, the Schrdinger equation is used instead of the Gross-Pitaevski equation. We calculate the atomic density, the chemical potential, the critical temperature and the condensate fraction. The role of the relative depth of the dimple potential with respect to the linear trap in large condensate formation at enhanced temperatures is clearly revealed. Moreover, we also present a semi-classical method for calculating various quantities such as entropy analytically. Moreover, we compare the results of this paper with the results of a previous paper in which the harmonic trap with a dimple potential in 1D is investigated. 展开更多
关键词 Bose–Einstein condensate linear trap a dimple potential Dirac δ potential
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Evaluation of Particle Numbers via Two Root Mean Square Radii in a 2-Species Bose–Einstein Condensate
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作者 贺彦章 刘益民 鲍诚光 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第8期220-222,共3页
The coupled Gross–Pitaevskii equations for two-species BEC have been solved analytically under the Thomas-Fermi approximation(TFA). Based on the analytical solution, two formulae are derived to relate the particle nu... The coupled Gross–Pitaevskii equations for two-species BEC have been solved analytically under the Thomas-Fermi approximation(TFA). Based on the analytical solution, two formulae are derived to relate the particle numbers N_A and N_B with the root mean square radii of the two kinds of atoms. Only the case that both kinds of atoms have nonzero distribution at the center of an isotropic trap is considered. In this case the TFA has been found to work nicely. Thus, the two formulae are applicable and are useful for the evaluation of N_A and N_B. 展开更多
关键词 Bose-Einstein condensation 2-species BEC root mean square radius determination of particlenulnbers
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