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991.
In this article, a multiobjective problem with a feasible set defined by inequality, equality and set constraints is considered, where the objective and constraint functions are locally Lipschitz. Several constraint qualifications are given and the relations between them are analyzed. We establish Kuhn-Tucker and strong Kuhn-Tucker necessary optimality conditions for (weak) quasi e?ciency in terms of the Clarke subdifferential. By using two new classes of generalized convex functions, su?cient conditions for local (weak) quasi e?cient are also provided. Furthermore, we study the Mond-Weir type dual problem and establish weak, strong and converse duality results. 相似文献
992.
Delay‐dependent criteria on the global attractivity of Nicholson's blowflies model with patch structure
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Renwei Jia Zhiwen Long Mingquan Yang 《Mathematical Methods in the Applied Sciences》2017,40(11):4222-4232
In this paper, we investigate the effect of delay on the asymptotic behavior of Nicholson's blowflies model with patch structure and multiple time‐varying delays. By using the fluctuation lemma and some differential inequality technique, delay‐dependent criteria are obtained for the global attractivity of the addressed system. Meanwhile, some numerical examples are given to illustrate the feasibility of the theoretical results. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
993.
The existence of a positive solution for nonlinear fractional differential equations with integral boundary value conditions
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Alberto Cabada Sladjana Dimitrijevic Tatjana Tomovic Suzana Aleksic 《Mathematical Methods in the Applied Sciences》2017,40(6):1880-1891
In this paper, first, we consider the existence of a positive solution for the nonlinear fractional differential equation boundary value problem where 0≤λ < 1,CDα is the Caputo's differential operator of order α, and f:[0,1] × [0,∞)→[0,∞) is a continuous function. Using some cone theoretic techniques, we deduce a general existence theorem for this problem. Then, we consider two following more general problems for arbitrary α, 1≤n < α≤n + 1: Problem 1: where , 0≤λ < k + 1; Problem 2: where 0≤λ≤α and Dα is the Riemann–Liouville fractional derivative of order α. For these problems, we give existence results, which improve recent results in the literature. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
994.
利用Banach空间中的锥理论和不动点定理讨论了非线性算子方程变号解的存在性,给出了E_u_0空间下非线性算子方程变号解至少有一个变号解、一个正解和一个负解的条件,并讨论了仅通过一个上解条件得出非线性算子方程变号解的存在性定理. 相似文献
995.
996.
Todd A. Lauderdale 《International Journal of Non》2005,40(5):715-727
As attractive alternatives to a set of three Euler angles, the rotation of a rigidly deforming body is often represented using four or more parameters. The accompanying parameter constraints introduce generalized constraint forces in the equations of motion which can often negate the benefits of a particular parameterization. In this paper, we discuss situations where the parameter constraints are not imposed. Thus, although the body no longer deforms rigidly, it does deform homogeneously. This allows the theory of a Cosserat point (or, equivalently, the theory of a pseudo-rigid body) to be used to establish equations governing its motion. Earlier work on this topic by O’Reilly and Varadi considered the four Euler parameters and the single Euler parameter constraint. Here, we consider Poincaré's six parameter representation of a rotation tensor, and, complementing earlier work, discuss numerical implementation and representative simulations. One of the contributions of this paper is the development of a viscoelastic Cosserat point, whose equations of motion are free from parameter constraints and singularities, that can be used to approximate the motion of a rigid body. 相似文献
997.
新型挠性支承结构及其加工方法 总被引:3,自引:1,他引:3
在分析现有几种挠性支承结构和加工方法的优缺点的基础上,研究了一种新型的挠性支承结构并在充分分析这种结构的优点后,提出了针对这种结构的切实可行的加工方法。此外还讨论了这种加工方法所存在的问题。 相似文献
998.
Voronov V. P. Belyakov M. Yu. Gorodetskii E. E. Kulikov V. D. Muratov A. R. Nagaev V. B. 《Transport in Porous Media》2003,51(2):123-140
The adiabatic calorimetry method is used to measure the isochoric heat capacity and the dew-bubble curves for the methane-normal pentane mixtures in bulk for three different mixture compositions of n-pentane. The near-critical behavior of the mixture heat capacity indicates that at low n-pentane concentrations, this system is close to the special point of the critical locus. The effect of porous medium has been investigated for one of the mixtures studied in bulk. It has been shown that in porous medium the essential shift of the dew-bubble curve takes place. In our opinion this shift is caused by the formation of wetting film on the surface of porous medium. The estimation of film thickness resulting from the data obtained yields the value 7–8 nm. 相似文献
999.
弥散型核燃料元件热应力的计算模拟 总被引:2,自引:0,他引:2
针对弥散型燃料板的具体形状,选择了一种能够反映其实际变形特征的三维代表性体积单元作为研究对象;利用有限元法对其热力耦合行为进行了弹塑性分析,研究了热应力在燃料和基体中的分布特征. 相似文献
1000.
Zhang Ju-ling 《应用数学和力学(英文版)》1994,15(1):81-91
A second order linear ordinary differential equation has been studied, and the complete expresson, of the formal uniformly
valid asymptotic solutions to the equation near turning point is obtained by using extended Airy function. 相似文献