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991.
Alan V. Lair 《Journal of Mathematical Analysis and Applications》2008,346(1):99-106
We consider the equation Δu=p(x)uα+q(x)uβ on RN (N?3) where p, q are nonnegative continuous functions and 0<α?β. We establish conditions sufficient to ensure the existence and nonexistence of nonnegative entire large solutions of the equation. 相似文献
992.
993.
In this paper, we construct an augmented system of the standard monotone linear complementarity problem (LCP), and establish
the relations between the augmented system and the LCP. We present a smoothing-type algorithm for solving the augmented system.
The algorithm is shown to be globally convergent without assuming any prior knowledge of feasibility/infeasibility of the
problem. In particular, if the LCP has a solution, then the algorithm either generates a maximal complementary solution of
the LCP or detects correctly solvability of the LCP, and in the latter case, an existing smoothing-type algorithm can be directly
applied to solve the LCP without any additional assumption and it generates a maximal complementary solution of the LCP; and
that if the LCP is infeasible, then the algorithm detect correctly infeasibility of the LCP. To the best of our knowledge,
such properties have not appeared in the existing literature for smoothing-type algorithms.
This work was partially supported by the National Natural Science Foundation of China (Grant No. 10571134), the Natural Science
Foundation of Tianjin (Grant No. 07JCYBJC05200), and the Scientific Research Foundation for the Returned Overseas Chinese
Scholars, State Education Ministry. 相似文献
994.
E. M. Abbasov O. A. Dyshin B. A. Suleimanov 《Computational Mathematics and Mathematical Physics》2008,48(12):2194-2210
A method is proposed for constructing stable approximate wavelet decompositions of weak solutions to boundary value problems for the unsteady porous-medium flow equation with discontinuous coefficients and inexact data. The method is based on the general scheme for finite-dimensional approximation in Tikhonov regularization and on multiresolution analysis with basis functions defined as the product of one-dimensional Daubechies wavelets. 相似文献
995.
V. N. Paimushin V. A. Ivanov S. A. Lukankin A. A. Bushkov A. E. Vyalkov 《Mechanics of Composite Materials》2005,41(1):23-32
Equations are set up for describing, in a correct statement and with an accuracy sufficient in actual practice, the shear buckling modes (BMs) of cylindrical sandwich shells with a transversely soft core of arbitrary thickness. Based on them, solutions are obtained to a number of problems on the buckling instability according to shear modes under some force and thermal loadings. It is found that the BMs occur in the shell along the circumferential and axial directions if, in the precritical state, a normal compressive stress arises in the transverse direction. It is shown that this condition is fulfilled in the following cases: in axial tension of the shell with unequal forces applied to the end faces of bearing layers (the parameter of critical load is maximum if the tensile forces are equal); under external (internal) pressure; on cooling the outer and heating the inner layers. The results obtained are presented in the form of simple analytical formulas for determining the corresponding critical parameters of the force and thermal actions.Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 1, pp. 37–48, January–February, 2005. 相似文献
996.
Nonlinear resonances and self-excited oscillations of a rotor caused by radial clearance and collision 总被引:1,自引:0,他引:1
This paper investigates oscillations in a flexible rotor system with radial clearance between an outer ring of the bearing
and a casing by experiments and numerical simulations. The mathematical model considers the collisions of the bearing with
the casing. The following phenomena are found: (1) Nonlinear resonances of subharmonic, super-subharmonic and combination
oscillation occur. (2) Self-excited oscillation of a forward whirling mode occurs in a wide range above the major critical
speed. (3) Entrainment phenomena from self-excited oscillation to nonlinear forced oscillation occur at these nonlinear resonance
ranges. Moreover, this study analyzes periodic solutions of the mathematical model by the Harmonic Balance Method (HBM). As
the results, the nonlinear resonances of subharmonic oscillation and its entrainment phenomenon can be explained theoretically
by investigating the stability of the periodic solutions. The influence of the static force and the bearing damping on these
oscillation are also clarified. 相似文献
997.
In this paper, we study the diffusive vector disease model with delay. This problem with strong biological background has attracted much research attention. We focus on the existence of traveling wave fronts, and find that there is a moving zone for the transition from the disease-free state to the infective state. To complete the theoretical analysis, we employ the mathematical tools including the monotone iteration technique as well as the upper and lower solution method. 相似文献
998.
Multiplicity of positive solutions to some second order m-point boundary value problems are considered. By fixed-point theorems in a cone, some new results are obtained. The associated Green’s function of these problems are also given. 相似文献
999.
The paper is devoted to periodic attractor of delayed Hopfield neural networks with time-varying.By constructing Lyapunov functionals and using inequality techniques,some new sufficient criteria are obtained to guarantee the existence and global exponential stability of periodic attractor.Our results improve and extend some existing ones in[13~14].One example is also worked out to demonstrate the advantages of our results. 相似文献
1000.
Novel CdClOH sub‐nanocone crystals were successfully synthesized on a large scale by a facile solution‐based method using polymers as crystal growth modifiers. The crystals showed cone‐like morphology. Some factors affecting the morphology and size of the product, such as reaction temperature, concentrations of polyacrylamide (PAM), and pH value of the solution, were systematically studied. Experiments implied that polymer PAM played a key role in the formation of CdClOH sub‐nanocones. A possible formation mechanism of CdClOH sub‐nanocones was suggested based on nucleation‐etching process‐recrystallization in a mild aqueous solution. Furthermore, the as‐prepared CdClOH sub‐nanocones could be further transformed into CdS hollow sub‐nanocones by an anion‐exchange reaction. 相似文献