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991.
Abstract A method for simultaneous measurement of heat and volume changes associated with phase transformations is presented. Examples for melting, polymorphism and structural relaxation illustrate the method. 相似文献
992.
993.
Jean-Luc Marichal Pierre Mathonet 《Journal of Mathematical Analysis and Applications》2011,380(1):105-116
By considering a least squares approximation of a given square integrable function f:n[0,1]→R by a multilinear polynomial of a specified degree, we define an index which measures the overall interaction among variables of f. This definition extends the concept of Banzhaf interaction index introduced in cooperative game theory. Our approach is partly inspired from multilinear regression analysis, where interactions among the independent variables are taken into consideration. We show that this interaction index has appealing properties which naturally generalize several properties of the Banzhaf interaction index. In particular, we interpret this index as an expected value of the difference quotients of f or, under certain natural conditions on f, as an expected value of the derivatives of f. Finally, we discuss a few applications of the interaction index in aggregation function theory. 相似文献
994.
We study a non-homogeneous boundary value problem in a smooth bounded domain in RN. We prove the existence of at least two non-negative and non-trivial weak solutions. Our approach relies on Orlicz-Sobolev spaces theory combined with adequate variational methods and a variant of Mountain Pass Lemma. 相似文献
995.
We investigate oscillatory properties of half-linear differential equations. The investigated half-linear equation is viewed as a perturbation of another (nonoscillatory) equation of the same form and perturbation is allowed both in the absolute term and in the derivative term. First, the Sturmian type theorem for solutions of the associated Riccati equation is established. In the second part of the paper we prove new half-linear oscillation criteria using the variational technique. 相似文献
996.
Local existence of multiple positive solutions to a singular cantilever beam equation 总被引:2,自引:0,他引:2
Qingliu Yao 《Journal of Mathematical Analysis and Applications》2010,363(1):138-861
By constructing suitable cone and control functions, we prove some local existence theorems of positive solutions for a singular fourth-order two-point boundary value problem. In mechanics, the problem is called cantilever beam equation. Furthermore, we improve a famous method appeared in the studies of singular boundary value problems. The approximation theorem of completely continuous operators and the Guo-Krasnosel'skii fixed point theorem of cone expansion-compression type play important parts in this work. 相似文献
997.
葛洵 《纯粹数学与应用数学》2010,26(3):420-425
证明了如果空间类K为D-空间类或闭遗传不可约空间类,则I(K)包含K.这一结果对于K为D空间类和闭遗传不可约空间类,肯定地回答了I(K)是否包含I^2(K)问题. 相似文献
998.
M. Mehdizadeh Khalsaraei 《Journal of Computational and Applied Mathematics》2010,235(1):137-143
In this paper, we investigate the positivity property for a class of 2-stage explicit Runge-Kutta (RK2) methods of order two when applied to the numerical solution of special nonlinear initial value problems (IVPs) for ordinary differential equations (ODEs). We also pay particular attention to monotonicity property. We obtain new results for positivity which are important in practical applications. We provide some numerical examples to illustrate our results. 相似文献
999.
In this paper the concept of lower and upper solutions combined with the fixed point theorem of Bohnnenblust–Karlin is used to investigate the existence of solutions for a class of the initial value problem for impulsive differential inclusions involving the Caputo fractional derivative. 相似文献
1000.
Dumitru Baleanu Alireza K. Golmankhaneh Ali K. Golmankhaneh 《International Journal of Theoretical Physics》2009,48(4):1044-1052
The fractional generalization of Nambu mechanics is constructed by using the differential forms and exterior derivatives of
fractional orders. The generalized Pfaffian equations are obtained and one example is investigated in details.
On leave of absence from Institute of Space Sciences, P.O. Box, MG-23, 76900, Magurele-Bucharest, Romania. 相似文献