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951.
Mohammed Al Horani 《Journal of Mathematical Analysis and Applications》2010,364(1):204-208
In this paper we study an inverse problem for a degenerate differential equation on a Banach space. A projection method will be used to reduce the problem to a regular abstract inverse problem. To this end some conditions on the operators are assumed to avoid the calculations of some inverses of the involved operators. 相似文献
952.
Sébastien Boucksom Philippe Eyssidieux Vincent Guedj Ahmed Zeriahi 《Acta Mathematica》2010,205(2):199-262
We define non-pluripolar products of an arbitrary number of closed positive (1, 1)-currents on a compact Kähler manifold X. Given a big (1, 1)-cohomology class α on X (i.e. a class that can be represented by a strictly positive current) and a positive measure μ on X of total mass equal to the volume of α and putting no mass on pluripolar sets, we show that μ can be written in a unique way as the top-degree self-intersection in the non-pluripolar sense of a closed positive current in α. We then extend Kolodziedj’s approach to sup-norm estimates to show that the solution has minimal singularities in the sense of Demailly if μ has L 1+ε -density with respect to Lebesgue measure. If μ is smooth and positive everywhere, we prove that T is smooth on the ample locus of α provided α is nef. Using a fixed point theorem, we finally explain how to construct singular Kähler–Einstein volume forms with minimal singularities on varieties of general type. 相似文献
953.
954.
Planning horizon is a key issue in production planning. Different from previous approaches based on Markov Decision Processes, we study the planning horizon of capacity planning problems within the framework of stochastic programming. We first consider an infinite horizon stochastic capacity planning model involving a single resource, linear cost structure, and discrete distributions for general stochastic cost and demand data (non-Markovian and non-stationary). We give sufficient conditions for the existence of an optimal solution. Furthermore, we study the monotonicity property of the finite horizon approximation of the original problem. We show that, the optimal objective value and solution of the finite horizon approximation problem will converge to the optimal objective value and solution of the infinite horizon problem, when the time horizon goes to infinity. These convergence results, together with the integrality of decision variables, imply the existence of a planning horizon. We also develop a useful formula to calculate an upper bound on the planning horizon. Then by decomposition, we show the existence of a planning horizon for a class of very general stochastic capacity planning problems, which have complicated decision structure. 相似文献
955.
Ahmed Bchatnia 《Applied Mathematics Letters》2010,23(8):935-939
In this note, we prove the global well posedness and the local energy decay for semilinear wave equation with small data. 相似文献
956.
A metrical common fixed point theorem for a pair of self mappings due to Sastry and Murthy (K.P.R. Sastry, I.S.R. Krishna Murthy, A common fixed points of two partially commuting tangential selfmaps on a metric space, J. Math. Anal. Appl. 250 (2000) 731734.) [8] is extended to symmetric spaces which in turn generalises a fixed point theorem due to Pant (R.P. Pant, Common fixed points of Lipschitz type mapping pairs, J. Math. Anal. Appl. 248 (1999) 280283.) [11] besides deriving some related results. Some illustrative examples to highlight the realised improvements are also furnished. 相似文献
957.
Matsuya Y Kawaguchi T Ishihara K Ahmed K Zhao QL Kondo T Nemoto H 《Organic letters》2006,8(20):4609-4612
Hybrid compounds of macrosphelides and epothilones, both of which are natural macrolides having a 16-membered skeleton, were designed and synthesized using a ring-closing metathesis (RCM) strategy. Some of these hybrids were found to exhibit notable apoptosis-inducing activity against human lymphoma cells with higher potency than parent natural macrosphelides, and to be a promising lead compound for development of a new antitumor agent. 相似文献
958.
This work presents the results of applying an advanced fault detection and isolation technique to centrifugal compressor;
this advanced technique uses physics models of the centrifugal compressor with a fuzzy modeling and control solution method.
The fuzzy fault detection and isolation has become an issue of primary importance in modern process engineering automation
as it provides the prerequisites for the task of fault detection. In this work, we present an application of this approach
in fault detection and isolation of surge in compression system. The ability to detect the surge is essential to improve reliability
and security of the gas compressor plants. We describe and illustrate an alternative implementation to the compression systems
supervision task using the basic principles of fuzzy fault detection and isolation associated with fuzzy modeling approach.
In this supervision task, the residual generation is obtained from the real input-output data process and the residual evaluation
is based on fuzzy logic method. The results of this application are very encouraging with relatively low levels of false alarms
and obtaining a good limitation of surge in natural gas pipeline compressors. 相似文献
959.
Mohammed Lemou 《Comptes Rendus Mathematique》2010,348(7-8):455-460
960.