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11.
D. Chiladze J. Carbonell S. Dymov V. Glagolev M. Hartmann V. Hejny A. Kacharava I. Keshelashvili A. Khoukaz H.R. Koch V. Komarov P. Kulessa A. Kulikov G. Macharashvili Y. Maeda T. Mersmann S. Merzliakov S. Mikirtytchiants A. Mussgiller M. Nioradze H. Ohm F. Rathmann R. Schleichert H.J. Stein H. Ströher Yu. Uzikov S. Yaschenko C. Wilkin 《Physics letters. [Part B]》2006
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Let G=(V,E) be a (directed) graph with vertex set V and edge (arc) set E. Given a set P of source-sink pairs of vertices of G, an important problem that arises in the computation of network reliability is the enumeration of minimal subsets of edges (arcs) that connect/disconnect all/at least one of the given source-sink pairs of P. For undirected graphs, we show that the enumeration problems for conjunctions of paths and disjunctions of cuts can be solved in incremental polynomial time. Furthermore, under the assumption that P consists of all pairs within a given vertex set, we also give incremental polynomial time algorithm for enumerating all minimal path disjunctions and cut conjunctions. For directed graphs, the enumeration problem for cut disjunction is known to be NP-complete. We extend this result to path conjunctions and path disjunctions, leaving open the complexity of the enumeration of cut conjunctions. Finally, we give a polynomial delay algorithm for enumerating all minimal sets of arcs connecting two given nodes s1 and s2 to, respectively, a given vertex t1, and each vertex of a given subset of vertices T2. 相似文献
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Boris Golinskii Leonid Golinskii 《Journal of Mathematical Analysis and Applications》1998,220(2):1050
The known conditions due to G. Baxter, Ya. L. Geronimus, and B. L. Golinskii which guarantee the uniform boundedness and/or uniform asymptotic representation for orthonormal polynomials on the unit circle are under consideration. We show that these conditions are in general not necessary. We discuss the relation between the orthonormal polynomials on the unit circle, the best approximations, and absolutely convergent Fourier series. 相似文献
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Victor N. Khrustalev Eugene A. Komissarov Oleg V. Kulikov 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(7):o374-o377
The macrocyclic title compound crystallizes as a dioxane solvate, C30H22Cl2N4O4·C4H8O2, with two independent formula units in the unit cell. The observed syn conformation is controlled by both intramolecular N—H...O hydrogen bonds and intermolecular C—H...π interactions. The relative macrocyclic inner bore is estimated to be 4.19 Å. In the crystal structure, molecules form dimers via intermolecular C—H...π interactions, and these dimers are, in turn, linked to form columns along the a axis by intermolecular C—H...O hydrogen bonds. Both X‐ray diffraction analysis and density functional theory (DFT) calculations reveal that the macrocycle possesses very high flexibility. This property, as well as the presence of six donor atoms accessible for coordination, makes the title macrocycle a very promising ligand for complexation with the majority of transition metals. 相似文献
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M. Yu. Kulikov A. M. Feigin G. R. Sonnemann 《Radiophysics and Quantum Electronics》2006,49(9):683-691
We propose a method for retrieval of directly unmeasurable concentrations of minor gas constituents of the mesosphere from
available experimental data using simplified models of atmospheric photochemical systems. The method is used for processing
of the results of simultaneous measurements of ozone and hydroxyl concentrations within the framework of the CRISTA-MAHRSI
satellite experiments. As a result, vertical distributions of concentrations of three more key chemical components of the
mesosphere, namely, atomic oxygen, atomic hydrogen, and hydroperoxide, were retrieved. It is shown that a limiting altitude-dependent
ratio between OH and O3 concentrations is valid in the mesosphere and lower thermosphere. It is found that CRISTA-MAHRSI data satisfy this ratio
up to an altitude of 87 km, but a strong discrepancy between theory and experiment arises in the upper region.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 9, pp. 760–769, September 2006. 相似文献