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681.
682.
683.
We investigate the existence of a weak solution u to the quasilineartwo-point boundary value problem We assume that 1 < p < p ¬ = 2, 0 < a < , andthat f L1(0,a) is a given function. The number k stands forthe k-th eigenvalue of the one-dimensional p-Laplacian. Letp p x/a) denote the eigenfunction associated with 1; then p(kp x/a) is the eigenfunction associated with k. We show the existenceof solutions to (P) in the following cases. (i) When k=1 and f satisfies the orthogonality condition the set of solutions is bounded. (ii) If k=1 and ft L1(0,a) is a continuous family parametrizedby t [0,1], with then there exists some t* [0,1] such that (P) has a solutionfor f = ft*. Moreover, an appropriate choice of t* yields asolution u with an arbitrarily large L1(0,a)-norm which meansthat such f cannot be orthogonal to pp x/a. (iii) When k 2 and f satisfies a set of orthogonality conditionsto p(k p x/a) on the subintervals , again, the set of solutions is bounded. is a continuous family satisfying either or another related condition, then there exists some t* [0,1]such that (P) has a solution for f = ft*. Prüfer's transformation plays the key role in our proofs.2000 Mathematical Subject Classification: primary 34B16, 47J10;secondary 34L40, 47H30. 相似文献
684.
Ravi P. AGARWAL Donal O'REGAN Svatoslav STANEK 《数学学报(英文版)》2006,22(3):827-832
A new upper and lower solution theory is presented for the second order problem (G'(y))'+ f(t, y) = 0 on finite and infinite intervals. The theory on finite intervals is based on a Leray-Schauder alternative, where as the theory on infinite intervals is based on results on the finite interval and a diagonalization process. 相似文献
685.
686.
Ivan P. Shestakov 《Proceedings of the American Mathematical Society》2004,132(2):313-316
Let be the algebra of classical real octonions or the (split) algebra of octonions over the finite field 2$">. Then the quotient loop of the Moufang loop of all invertible elements of the algebra modulo its center is not embedded into a loop of invertible elements of any alternative algebra.
687.
This paper investigates the existence of nontrivial solution for the three-point boundary value problem
688.
A. Horzela 《Czechoslovak Journal of Physics》2004,54(11):1329-1334
We consider noncanonical harmonic oscillator quantized as a representation of the so(2,1) algebra and investigate its termodynamical properties. For all temperatures the entropy of such a noncanonical oscillator is greater than the entropy of the canonical one. This may serve as an explanation why in the equilibrium the oscillator is canonical. 相似文献
689.
MichaelJohnO'Hara 《科学通报(英文版)》2004,49(17):1788-1800
The outcome of the Apollo lunar exploration program 1969-1974 was a model of lunar petrogenesis which ignored the probability of selective volatilisation of gases and alkalis from fire-fountaining lunar basalts. It overlooked the fact that the average compositions of the erupted basalts were those of plagioclase-saturated and low-pressure cotectic liquids on eruption, clearly indicating that they were not primary magmas. The basalts may have undergone evolution by gabbro fractionation within the lunar crust, perhaps in large lava lakes now solidified as the lunar maria. The existing model involving a global magma ocean and plagioclase flotation to form the lunar crust arises solely from the incorrect assumption that the basalts are primary magmas. The plagioclase flotation hypothesis requires the presence of a significant positive europium anomaly in the lunar highland crust, and was founded upon its alleged presence. However, that positive anomaly is neither established by the original data set nor by the much broader current data set. Critical observations, and experiments which will advance the debate are suggested, and alternative interpretations outlined. 相似文献
690.
为保护臭氧层,《蒙特利尔议定书》规定CFC-12为首批禁用物质,因此,寻找其替代物的工作日益紧迫。针对目前各种替代物的不足之处,运用多目标决策分析方法,筛选出一种新的绿色环保制冷剂“清华2号”(THR02),其热物理性能和循环参数与CFC-12非常接近,并进行了压缩机、润滑油和冰箱的性能试验以及循环的变工况模拟分析。结果表明THR02具有以下特点:不破坏臭氧层,温室效应低,不燃无毒,适用于原制冷系统、压缩机与冷冻油,热工性能好,可直接灌注,长期替代CFC-12,且可进一步替代HFC-134a。 相似文献