期刊文献+
共找到752篇文章
< 1 2 38 >
每页显示 20 50 100
Continuous Dependence of Bounded Φ-Variation Solutions on Parameters for Kurzweil Equations 被引量:3
1
作者 李宝麟 吴从炘 《Northeastern Mathematical Journal》 CSCD 2005年第4期421-430,共10页
The continuous dependence of bounded Φ-variation solutions on parameters for Kurzweil equations are established by using the functions of bounded Φ- variation that were introduced by Musielak-Orlice. These results a... The continuous dependence of bounded Φ-variation solutions on parameters for Kurzweil equations are established by using the functions of bounded Φ- variation that were introduced by Musielak-Orlice. These results are essential generalizations of continuous dependence of bounded variation solutions on parameters for Kurzweil equations. 展开更多
关键词 Kurzweil equation bounded Φ-variation solution continuous dependence on parameter
下载PDF
THE LIMITING PROFILE OF SOLUTIONS FOR SEMILINEAR ELLIPTIC SYSTEMS WITH A SHRINKING SELF-FOCUSING CORE
2
作者 金可 石影 谢华飞 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期583-608,共26页
In this paper,we consider the semilinear elliptic equation systems{△u+u=αQ_(n)(x)|u|^(α-2)|v|^(β)u in R^(N),-△v+v=βQ(x)|u|^(α)|v|^(β-2)v in R^(N),where N≥3,α,β>1,α+β<2^(*),2^(*)=2N/N-2 and Q_(n) are... In this paper,we consider the semilinear elliptic equation systems{△u+u=αQ_(n)(x)|u|^(α-2)|v|^(β)u in R^(N),-△v+v=βQ(x)|u|^(α)|v|^(β-2)v in R^(N),where N≥3,α,β>1,α+β<2^(*),2^(*)=2N/N-2 and Q_(n) are bounded given functions whose self-focusing cores{x∈R^(N)|Q_(n)(x)>0} shrink to a set with finitely many points as n→∞.Motivated by the work of Fang and Wang[13],we use variational methods to study the limiting profile of ground state solutions which are concentrated at one point of the set with finitely many points,and we build the localized concentrated bound state solutions for the above equation systems. 展开更多
关键词 Schrödinger system ground states solutions bound state solutions
下载PDF
Wave packet solutions in a bounded equatorial ocean and its interannual and decadal variabilities 被引量:2
3
作者 Dongling Zhang Juan Zhu +1 位作者 Xu Lu Ming Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第3期45-59,共15页
Linearized shallow water perturbation equations with approximation in an equatorial β plane are used to obtain the analytical solution of wave packet anomalies in the upper bounded equatorial ocean. The main results ... Linearized shallow water perturbation equations with approximation in an equatorial β plane are used to obtain the analytical solution of wave packet anomalies in the upper bounded equatorial ocean. The main results are as follows. The wave packet is a superposition of eastward travelling Kelvin waves and westward travelling Rossby waves with the slowest speed, and satisfies the boundary conditions of eastern and western coasts, respectively.The decay coefficient of this solution to the north and south sides of the equator is inversely proportional only to the phase velocity of Kelvin waves in the upper water. The oscillation frequency of the wave packet, which is also the natural frequency of the ocean, is proportional to its mode number and the phase velocity of Kelvin waves and is inversely proportional to the length of the equatorial ocean in the east-west direction. The flow anomalies of the wave packet of Mode 1 most of the time appear as zonal flows with the same direction. They reach the maximum at the center of the equatorial ocean and decay rapidly away from the equator, manifested as equatorially trapped waves. The flow anomalies of the wave packet of Mode 2 appear as the zonal flows with the same direction most of the time in half of the ocean, and are always 0 at the center of the entire ocean which indicates stagnation, while decaying away from the equator with the same speed as that of Mode 1. The spatial structure and oscillation period of the wave packet solution of Mode 1 and Mode 2 are consistent with the changing periods of the surface spatial field and time coefficient of the first and second modes of complex empirical orthogonal function(EOF)analysis of flow anomalies in the actual equatorial ocean. This indicates that the solution does exist in the real ocean, and that El Ni?o-Southern Oscillation(ENSO) and Indian Ocean dipole(IOD) are both related to Mode 2.After considering the Indonesian throughflow, we can obtain the length of bounded equatorial ocean by taking the sum of that of the tropical Indian Ocean and the tropical Pacific Ocean, thus this wave packet can also explain the decadal variability(about 20 a) of the equatorial Pacific and Indian Oceans. 展开更多
关键词 bounded EQUATORIAL OCEAN WAVE packet solutions DECADAL variability Kelvin WAVE Rossby WAVE
下载PDF
Analytical solutions for constant-rate test in bounded confined aquifers with non-Darcian effect 被引量:2
4
作者 Yi-jie Zong Li-hua Chen +4 位作者 Jian-jun Liu Yue-hui Liu Yong-xin Xu Fu-wan Gan Liang Xiao 《Journal of Groundwater Science and Engineering》 2022年第4期311-321,共11页
This paper proposes a simplified analytical solution considering non-Darcian and wellbore storage effect to investigate the pumping flow in a confined aquifer with barrier and recharge boundaries.The mathematical mode... This paper proposes a simplified analytical solution considering non-Darcian and wellbore storage effect to investigate the pumping flow in a confined aquifer with barrier and recharge boundaries.The mathematical modelling for the pumping-induced flow in aquifers with different boundaries is developed by employing image-well theory with the superposition principle,of which the non-Darcian effect is characterized by Izbash’s equation.The solutions are derived by Boltzmann and dimensionless transformations.Then,the non-Darcian effect and wellbore storage are especially investigated according to the proposed solution.The results show that the aquifer boundaries have non-negligible effects on pumping,and ignoring the wellbore storage can lead to an over-estimation of the drawdown in the first 10 minutes of pumping.The higher the degree of non-Darcian,the smaller the drawdown. 展开更多
关键词 Non-Darcian effect bounded aquifer Wellbore storage Izbash’s equation Analytical solution
下载PDF
BOUNDED TRAVELING WAVE SOLUTIONS OF VARIANT BOUSSINESQ EQUATION WITH A DISSIPATION TERM AND DISSIPATION EFFECT
5
作者 张卫国 刘强 +1 位作者 李正明 李想 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期941-959,共19页
This article studies bounded traveling wave solutions of variant Boussinesq equation with a dissipation term and dissipation effect on them. Firstly, we make qualitative analysis to the bounded traveling wave solution... This article studies bounded traveling wave solutions of variant Boussinesq equation with a dissipation term and dissipation effect on them. Firstly, we make qualitative analysis to the bounded traveling wave solutions for the above equation by the theory and method of planar dynamical systems, and obtain their existent conditions, number, and general shape. Secondly, we investigate the dissipation effect on the shape evolution of bounded traveling wave solutions. We find out a critical value r^* which can characterize the scale of dissipation effect, and prove that the bounded traveling wave solutions appear as kink profile waves if |r|≥ r^*; while they appear as damped oscillatory waves if |r| 〈 r^*. We also obtain kink profile solitary wave solutions with and without dissipation effect. On the basis of the above discussion, we sensibly design the structure of the approximate damped oscillatory solutions according to the orbits evolution relation corresponding to the component u(ξ) in the global phase portraits, and then obtain the approximate solutions (u(ξ), H(ξ)). Furthermore, by using homogenization principle, we give their error estimates by establishing the integral equation which reflects the relation between exact and approximate solutions. Finally, we discuss the dissipation effect on the amplitude, frequency, and energy decay of the bounded traveling wave solutions. 展开更多
关键词 Variant Boussinesq equation with dissipation term shape analysis bounded traveling wave solution error estimate dissipation effect
下载PDF
Global Bounded Solutions for the Keller-Segel Chemotaxis System with Singular Sensitivity
6
作者 Khalid Ahmed Abbakar Omer Khalil +3 位作者 Alhussein Mohamed Bechir Mahamat Abdoulaye Ali Abeer Alhadi 《Applied Mathematics》 2020年第10期985-990,共6页
In this paper, we consider the Neumann initial-boundary value problem for the Keller-Segel chemotaxis system with singular sensitivity <img src="Edit_4b941130-fc1e-4c9b-9626-4fd5a1f03836.bmp" alt="&q... In this paper, we consider the Neumann initial-boundary value problem for the Keller-Segel chemotaxis system with singular sensitivity <img src="Edit_4b941130-fc1e-4c9b-9626-4fd5a1f03836.bmp" alt="" />(0.1)<br /> <p> is considered in a bounded domain with smooth boundary, Ω &#8834;R<sup><i>n</i></sup> (<i>n</i> ≥ 1), where <i>d</i><sub>1</sub> > 0, <i>d</i><sub>2</sub> > 0 with parameter <i>χ</i> ∈ R. When <i>d</i><sub>1</sub> = <i>d</i><sub>2</sub> + <i>χ</i>, satisfying for all initial data 0 ≤ <i>n</i><sub>0</sub> ∈ <i>C</i><sup>0</sup><img src="Edit_4898c7a9-f047-4856-b9ad-8d42ecf262a2.bmp" alt="" /> and 0 < <i>v</i><sub>0</sub>∈ <i>W</i><sup>1,∞</sup> (Ω), we prove that the problem possesses a unique global classical solution which is uniformly bounded in Ω × (0, ∞). </p> 展开更多
关键词 Keller-Segel System CHEMOTAXIS Global bounded solution Singular Sensitivity
下载PDF
Ψ-bounded Solutions for a System of Difference Equations on Z
7
作者 HAN YU-LIANG LIu BAI-FENG SUN XI-DONG 《Communications in Mathematical Research》 CSCD 2011年第4期331-342,共12页
In this work we discuss the existence of ψ-bounded solutions for linear difference equations. We present a necessary and sufficient condition for the existence of ψ--bounded solutions for the linear nonhomogeneous d... In this work we discuss the existence of ψ-bounded solutions for linear difference equations. We present a necessary and sufficient condition for the existence of ψ--bounded solutions for the linear nonhomogeneous difference equation x(n+1)=A(n)x(n)+f(n) for every ψ-bounded sequence f(n). 展开更多
关键词 difference equation ψ-bounded solution EXISTENCE
下载PDF
Boundedness of Solutions for Elliptic Variational Inequalities
8
作者 Ye Ruifen(Department of Mathematics, Guangzhou Teachers’ College, 510400) 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第1期56-62,共7页
Boundedness of Solutions for Elliptic Variational InequalitiesBoundednessofSolutionsforEllipticVariationalIn... Boundedness of Solutions for Elliptic Variational InequalitiesBoundednessofSolutionsforEllipticVariationalInequalities¥YeRuif... 展开更多
关键词 椭圆形变分不等式 有界性
下载PDF
Upper Bound Solutions for Uplift Ultimate Bearing Capacity of Suction Caisson Foundation 被引量:1
9
作者 DAI Guo-liang ZHU Wen-bo +2 位作者 ZHAI Qian GONG Wei-ming ZHAO Xue-liang 《China Ocean Engineering》 SCIE EI CSCD 2019年第6期685-693,共9页
Suction caisson foundation derives most of their uplift resistance from passive suction developed during the pullout movement. It was observed that the passive suction generated in soil at the bottom of the caisson an... Suction caisson foundation derives most of their uplift resistance from passive suction developed during the pullout movement. It was observed that the passive suction generated in soil at the bottom of the caisson and the failure mode of suction caisson foundation subjecting pullout loading behaves as a reverse compression failure mechanism.The upper bound theorems have been proved to be a powerful method to find the critical failure mechanism and critical load associated with foundations, buried caissons and other geotechnical structures. However, limited attempts have been reported to estimate the uplift bearing capacity of the suction caisson foundation using the upper bound solution. In this paper, both reverse failure mechanisms from Prandtl and Hill were adopted as the failure mechanisms for the computation of the uplift bearing capacity of the suction caisson. New equations were proposed based on both failure mechanisms to estimate the pullout capacity of the suction caisson. The proposed equations were verified by the test results and experimental data from published literature. And the two solutions agree reasonably well with the other test results. It can be proved that both failure mechanisms are reasonably and more consistent with the actual force condition. 展开更多
关键词 suction caisson foundation bearing capacity upper bound solution failure mechanism
下载PDF
Vertex solution theorem for the upper and lower bounds on the dynamic response of structures with uncertain-but-bounded parameters 被引量:4
10
作者 Zhiping Qiu Xiaojun Wang Institute of Solid Mechanics, Beihang University, 100083 Beijing, China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第3期367-379,共13页
The aim of this paper is to evaluate the effects of uncertain-but-bounded parameters on the dynamic response of structures. By combining the interval mathematics and the finite element analysis, the mass matrix, dampi... The aim of this paper is to evaluate the effects of uncertain-but-bounded parameters on the dynamic response of structures. By combining the interval mathematics and the finite element analysis, the mass matrix, damping matrix, stiffness matrix and the external loads are represented as interval matrices and vector. With the help of the optimization theory, we present the vertex solution theorem for determining both the exact upper bounds or maximum values and the exact lower bounds or minimum values of the dynamic response of structures, in which these parameters reach their extreme values on the boundary of the interval mass, damping, stiffness matrices and the interval extemal loads vector. Three examples are used to illustrate the computational aspects of the presented vertex solution theorem. 展开更多
关键词 Dynamic response Vertex solution theorem Uncertain-but-bounded parameters
下载PDF
Novel Bounds for Solutions of Nonlinear Differential Equations
11
作者 A. A. Martynyuk 《Applied Mathematics》 2015年第1期182-194,共13页
In this paper the estimates for norms of solutions to nonlinear systems are obtained via an integral inequality. As an application we considered affine control systems and systems of equations for synchronization of m... In this paper the estimates for norms of solutions to nonlinear systems are obtained via an integral inequality. As an application we considered affine control systems and systems of equations for synchronization of motions. 展开更多
关键词 NONLINEAR Systems NOVEL boundS for solutions Stability SYNCHRONIZATION
下载PDF
Recrystallization of freezable bound water in aqueous solutions of medium concentrations
12
作者 赵立山 潘礼庆 +2 位作者 纪爱玲 曹则贤 王强 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期294-298,共5页
For aqueous solutions with freezable bound water, vitrification and recrystallization are mingled, which brings difficulty to application and misleads the interpretation of relevant experiments. Here, we report a quan... For aqueous solutions with freezable bound water, vitrification and recrystallization are mingled, which brings difficulty to application and misleads the interpretation of relevant experiments. Here, we report a quantification scheme for the freezable bound water based on the water-content dependence of glass transition temperature, by which also the concentration range for the solutions that may undergo recrystallization finds a clear definition. Furthermore, we find that depending on the amount of the freezable bound water, different temperature protocols should be devised to achieve a complete recrystallization. Our results may be helpful for understanding the dynamics of supercooled aqueous solutions and for improving their manipulation in various industries. 展开更多
关键词 recrystallization aqueous solution glass transition freezable bound water
下载PDF
REMARKS ON BOUNDS ON THE DISCREPANCY OF APPROXIMATE SOLUTIONS CONSTRUCTED BY GODUNOV'S SCHEME
13
作者 王靖华 《Acta Mathematica Scientia》 SCIE CSCD 1989年第4期437-452,共16页
The bounds on the discrepancy of approximate solutions constructed by Gedunov's scheme to IVP of isentropic equations of gas dynamics are obtained, Three well-knowu results obtained by Lax for shock waves with sma... The bounds on the discrepancy of approximate solutions constructed by Gedunov's scheme to IVP of isentropic equations of gas dynamics are obtained, Three well-knowu results obtained by Lax for shock waves with small jumps for general quasilinear hyperbolic systems of conservation laws are extended to shock waves for isentropic equations of gas dynamics in a bounded invariant region with ρ=0 as one of boundries of the region. Two counterexamples are given to show that two iuequalities given by Godunov do not hold for all rational numbers γ∈(1, 3]. It seems that the approach by Godunov to obtain the forementioned bounds may not be possible. 展开更多
关键词 TE REMARKS ON boundS ON THE DISCREPANCY OF APPROXIMATE solutions CONSTRUCTED BY GODUNOV’S SCHEME
下载PDF
SIGN-CHANGING SOLUTIONS FOR SCHRDINGER EQUATIONS WITH VANISHING AND SIGN-CHANGING POTENTIALS 被引量:1
14
作者 吴元泽 黄毅生 刘增 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期691-702,共12页
In this article, we study the existence of sign-changing solutions for the following SchrSdinger equation -△u + λV(x)u = K(x)|u|^p-2u x∈R^N, u→0 as |x|→ +∞, 2N where N ≥ 3, λ〉 0 is a parameter, 2 〈... In this article, we study the existence of sign-changing solutions for the following SchrSdinger equation -△u + λV(x)u = K(x)|u|^p-2u x∈R^N, u→0 as |x|→ +∞, 2N where N ≥ 3, λ〉 0 is a parameter, 2 〈 p 〈 2N/N-2, and the potentials V(x) and K(x) satisfy some suitable conditions. By using the method based on invariant sets of the descending flow, we obtain the existence of a positive ground state solution and a ground state sign-changing solution of the above equation for small λ, which is a complement of the results obtained by Wang and Zhou in [J. Math. Phys. 52, 113704, 2011]. 展开更多
关键词 Variational methods bounded state solutions sign-changing solutions
下载PDF
Upper Bound Solution of Soil Slope Stability under Coupling Effect of Rainfall and Earthquake 被引量:1
15
作者 尹小军 王兰民 《Journal of Donghua University(English Edition)》 EI CAS 2019年第4期357-363,共7页
Based on the limit analysis upper bound method,a new model of soil slope collapse has been proposed which consists of two rigid block zones and a plastic shear zone.Soil slope was induced failure by coupling effect of... Based on the limit analysis upper bound method,a new model of soil slope collapse has been proposed which consists of two rigid block zones and a plastic shear zone.Soil slope was induced failure by coupling effect of rainfall and earthquake,and these blocks were also incorporated horizontal earthquake force and vertical gravitate.The velocities and forces were analyzed in three blocks,and the expression of velocity discontinuities was obtained by the principle of incompressibility.The external force work for the blocks,the internal energy of the plastic shear zone and the velocity discontinuous were solved.The present stability ratios are compared to the prevenient research,which shows the superiority of the mechanism and rationality of the analysis.The critical height of the soil slope can provide theoretical basis for slope support and design. 展开更多
关键词 soil slope coupling effect upper bound solutION STABILITY ratio EARTHQUAKE RAINFALL
下载PDF
Exponential Dichotomy and Eberlein-Weak Almost Periodic Solutions 被引量:1
16
作者 Elhadi Ait Dads Samir Fatajou Lahcen Lhachimi 《Applied Mathematics》 2012年第9期969-975,共7页
We give sufficient conditions ensuring the existence and uniqueness of an Eberlein-weakly almost periodic solution to the following linear equation dx/dt(t) = A(t)x(t) + f(t) in a Banach space X, where (A(t)) t ∈□ i... We give sufficient conditions ensuring the existence and uniqueness of an Eberlein-weakly almost periodic solution to the following linear equation dx/dt(t) = A(t)x(t) + f(t) in a Banach space X, where (A(t)) t ∈□ is a family of infinitesimal generators such that for all t ∈□, A(t + T) = A(t) for some T > 0, for which the homogeneuous linear equation dx/dt(t) = A(t)x(t) is well posed, stable and has an exponential dichotomy, and f:□ →X is Eberlein-weakly amost periodic. 展开更多
关键词 bounded solutions ALMOST PERIODIC and Eberlein WEAK ALMOST PERIODIC Functions Exponential DICHOTOMY Linear Differential Equations
下载PDF
A new failure mechanism for deep cavity and upper bound solution of supporting pressure 被引量:4
17
作者 张道兵 刘智振 张佳华 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第9期2082-2091,共10页
The investigation of supporting pressure is of great significance to the design of underground structures.Based on the kinematical approach of limit analysis,an improved failure mechanism is proposed,and the supportin... The investigation of supporting pressure is of great significance to the design of underground structures.Based on the kinematical approach of limit analysis,an improved failure mechanism is proposed,and the supporting pressure is investigated for deep buried cavity.Three failure mechanisms are first introduced according to the existing failure mechanisms of geotechnical structures of limit analysis.A comparison with respect to the optimal failure mechanisms and the upper bound solutions provided among these three mechanisms are then conducted in an attempt to obtain the improved failure mechanism.The results provided by the improved failure mechanism are in good agreement with those by the existing method,the numerical solution and field monitoring,which demonstrates that the proposed failure mechanism is effective for the upper bound analysis of supporting pressure. 展开更多
关键词 失效机理 支承压力 上限解 破坏机制 支撑压力 极限分析 地下结构 岩土结构
下载PDF
Upper bound analytical solution for surrounding rock pressure of shallow unsymmetrical loading tunnels 被引量:6
18
作者 雷明锋 彭立敏 +2 位作者 施成华 谢友均 谭立新 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2339-2347,共9页
By combining the results of laboratory model tests with relevant flow rules, the failure mode of shallow unsymmetrical loading tunnels and the corresponding velocity field were established. According to the principle ... By combining the results of laboratory model tests with relevant flow rules, the failure mode of shallow unsymmetrical loading tunnels and the corresponding velocity field were established. According to the principle of virtual power, the upper bound solution for surrounding rock pressure of shallow unsymmetrical loading tunnel was derived and verified by an example. The results indicate that the calculated results of the derived upper bound method for surrounding rock pressure of shallow unsymmetrical loading tunnels are relatively close to those of the existing "code method" and test results, which means that the proposed method is feasible. The current code method underestimates the unsymmetrical loading feature of surrounding rock pressure of shallow unsymmetrical loading tunnels, so it is unsafe; when the burial depth is less or greater than two times of the tunnel span and the unsymmetrical loading angle is less than 45°, the upper bound method or the average value of the results calculated by the upper bound method and code method respectively, is comparatively reasonable. When the burial depth is greater than two times of the tunnel span and the unsymmetrical loading angle is greater than 45°, the code method is more suitable. 展开更多
关键词 浅埋偏压隧道 围岩压力 上限解 解析解 模型试验 计算结果 破坏模式 虚功原理
下载PDF
ON GLOBAL BEHAVIOR OF WEAK SOLUTIONS OF COMPRESSIBLE FLOWS OF NEMATIC LIQUID CRYSTALS
19
作者 王伟伟 《Acta Mathematica Scientia》 SCIE CSCD 2015年第3期650-672,共23页
In this article, we investigate the global behavior of weak solutions of a simplified Ericksen-Leslie system for compressible flows of nematic liquid crystals in time in a bounded three-dimension domain-arbitrary forc... In this article, we investigate the global behavior of weak solutions of a simplified Ericksen-Leslie system for compressible flows of nematic liquid crystals in time in a bounded three-dimension domain-arbitrary forces. By adapting the arguments for the compressible Navier-Stokes equations, and carefully analyzing the direction field of liquid crystals in the equations of angular momentum, we show the existence of bounded absorbing sets, global bounded trajectories, and global attractors to weak solutions of compressible flows of nematic liquid crystals with the adiabatic constant γ〉5/3. 展开更多
关键词 Liquid crystals weak solutions bounded absorbing set bounded trajectories ATTRACTOR
下载PDF
Eventually vanished solutions of a forced Liénard system
20
作者 张永新 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第10期1335-1344,共10页
In this paper, we aim to find eventually vanished solutions, a special class of bounded solutions which tend to 0 as t → ±∞), to a Lienard system with a time-dependent force. Since it is not a Hamiltonian syst... In this paper, we aim to find eventually vanished solutions, a special class of bounded solutions which tend to 0 as t → ±∞), to a Lienard system with a time-dependent force. Since it is not a Hamiltonian system with small perturbations, the well-known Melnikov method is not applicable to the determination of the existence of eventually vanished solutions. We use a sequence of periodically forced systems to approximate the considered system, and find their periodic solutions. Difficulties caused by the non- Hamiltonian form are overcome by applying the Schauder's fixed point theorem. We show that the sequence of the periodic solutions has an accumulation giving an eventually vanished solution of the forced Lienard system. 展开更多
关键词 eventually vanished bounded solution non-Hamiltonian ACCUMULATION
下载PDF
上一页 1 2 38 下一页 到第
使用帮助 返回顶部