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排序方式: 共有434条查询结果,搜索用时 593 毫秒
1.
By using the theory of coincidence degree, we study a kind of periodic solutions to p-Laplacian neutral functional differential equation with multiple deviating arguments, a new result on the existence of periodic solutions is obtained. 相似文献
2.
采用从头计算方法,计算了反式和顺式聚乙炔的氢原子在垂直于聚乙炔分子面方向振动的红外光谱,计算表明,Gibson等用红外吸收实验所测得的谱线的确是聚乙炔的CH面外振动产生的谱线,经100℃长时间加热后,顺式聚乙炔变为反式聚炔,但波数为740cm^-1的谱级仍保留5%的强度。 相似文献
3.
Ground state solution for differential equations with left and right fractional derivatives 下载免费PDF全文
César Torres 《Mathematical Methods in the Applied Sciences》2015,38(18):5063-5073
In this work, we study the existence of positive solutions for a class of fractional differential equation given by (1) where . Using the mountain pass theorem and comparison argument, we prove that (1) at least has one nontrivial solution. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
4.
孙元功 《纯粹数学与应用数学》2002,18(2):170-173
对于一类特殊的具有时滞的二阶次线性强迫微分方程x"(t) +a (t)|x(τ(t))|γsgnx(τ(t)) =g(t)(0<τ<1),给出了它的所有解振动的一个充要条件. 相似文献
5.
Wu Shaoping 《数学年刊B辑(英文版)》1996,17(2):245-256
The existence of at least two homoclinic orbits for Lagrangian system (LS) is proved, wherethe Lagrangian L(t,x,y) =1/2∑aij(x)yiyj-V(t, x), in which the potential V(t,x) is globallysurperquadratic in x and T-periodic in t. The Concentration-Compactness Lemma and Mini-max argument are used to prove the existences. 相似文献
6.
In this paper we study the 3-state Potts model on the triangular lattice which has two- and three-site interactions. Using a Peierls argument we obtain a rigorous bound on the transition temperature, thereby disproving a conjecture on the location of its critical point. Low-temperature series are generated and analyzed for three particular choices of the coupling constants; a phase diagram is then drawn on the basis of these considerations. Our analysis indicates that the antiferromagnetic transition and the transition along the coexistence line are of first order, implying the existence of a multicritical point in the ferromagnetic region. Relation of the triangularq-state Potts model with other lattice-statistical problems is also discussed. In particular, an Ashkin-Teller model and the hard-hexagon lattice gas solved by Baxter emerge as special cases in appropriate limits.Supported in part by NSF grant No. DMR 78-18808. 相似文献
7.
Water-like lattice gases on the triangular and body-centered cubic lattices are investigated. Molecules may reside on the lattice sites in either of two possible orientations, a hydrogen bond being formed between molecules on neighboring sites if they have the proper orientation with respect to one another. For a range of chemical potential at sufficiently low temperatures, the models are shown to have an ordered phase consisting of an open, hydrogen-bonded, icelike structure. The models are shown to be transitionfree at sufficiently high temperature, indicating the existence of a critical point.Research supported in part by the U.S. National Science Foundation, Grant CHE-7726177, and by The Robert A. Welch Foundation, Grant P-446. 相似文献
8.
We obtain an upper bound for the quantity
. Here I is an interval,
is the set of rational numbers q=m/n
I such that nx, and f(q) is an arbitrary real-valued additive function of rational argument. The interval I and function f may depend on x3. 相似文献
9.
Yuan Gong Sun 《Journal of Mathematical Analysis and Applications》2003,286(1):363-367
In the case of oscillatory potentials, we give sufficient conditions for the oscillation of the forced nonlinear second order differential equations with delayed argument in the form
10.
高正晖 《数学的实践与认识》2008,38(11):178-183
研究了一类含连续分布滞量和阻尼项的非线性双曲型偏微分方程组运用黎卡提变换获得了该方程组在两类边值条件下解振动的充分条件. 相似文献