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91.
Algorithms for detecting optimal hereditary structures in graphs, with application to clique relaxations 总被引:1,自引:0,他引:1
Svyatoslav Trukhanov Chitra Balasubramaniam Balabhaskar Balasundaram Sergiy Butenko 《Computational Optimization and Applications》2013,56(1):113-130
Given a simple undirected graph, the problem of finding a maximum subset of vertices satisfying a nontrivial, interesting property Π that is hereditary on induced subgraphs, is known to be NP-hard. Many well-known graph properties meet the above conditions, making the problem widely applicable. This paper proposes a general purpose exact algorithmic framework to solve this problem and investigates key algorithm design and implementation issues that are helpful in tailoring the general framework for specific graph properties. The performance of the algorithms so derived for the maximum s-plex and the maximum s-defective clique problems, which arise in network-based data mining applications, is assessed through a computational study. 相似文献
92.
93.
94.
Danilov Felix I. Bogdanov Dmytro A. Smyrnova Olena V. Korniy Sergiy A. Protsenko Vyacheslav S. 《Journal of Solid State Electrochemistry》2022,26(4):939-957
Journal of Solid State Electrochemistry - The electrochemical deposition of a nickel–iron alloy from a plating solution based on a deep eutectic solvent (a eutectic mixture of ethylene glycol... 相似文献
95.
Olha Мykhailenko Sergiy Chetvernya Ivan Bezruk Yrii Buydin Nadija Dhurenko Olena Рalamarchuk Liudas Ivanauskas Victoriya Georgiyants 《Biomedical chromatography : BMC》2022,36(7):e5369
Iris genus plants are a valuable source of bioactive compounds, which are an important component for pharmaceutical development. The present article shows the potential for mineral nutrition with application of magnesium sulfate, iron chelates and potassium oxide affecting the phenolic compound contents in Iris hybrida ‘Tsikavynka’, I. hybrida ‘Tambo’ and I. hybridа ‘Widecombe Fire’. The effect of mineral processing was specific to plant organs and varied in the component composition. The Iris rhizomes had an increased total phenolic compound content after treatment (up to 10% of the total isoflavonoid content, up to 8% of phenolic acids, up to 5% of γ-pyrones and up to 13% of flavonoids), determined using UV–vis spectroscopy. A positive effect of nutrition on the biosynthesis and content of individual isoflavonoids (tectoridin, nigricin d -glucoside, genistin, iristectorigenin B, nigricin, irigenin and irisolidone) and xanthone mangiferin in Iris rhizomes by HPLC was established. In addition, an increase in the chlorogenic acid amount in Iris leaves was noted. The results demonstrate the sensitivity of Iris phenylpropanoid metabolism to mineral nutrition and can be used to predict medical plant cultivation with increased content of bioactive constituents. 相似文献
96.
G. I. Gurina V. D. Evtushenko A. Yu. Kobyakov V. M. Koshkin 《Theoretical and Experimental Chemistry》1985,21(6):718-719
It has been established that reductants sensitize the photolysis of PbI2 but only commencing from a threshold concentration. An anisotropy is observed in the photodecomposition of single crystals in the presence of amines. It has been shown that intercalation competes with the sensitization of photolysis. An interpretation of the effect is proposed.Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 21, No. 6, pp. 757–759, November–December, 1985.We thank L. A. Ageev, A. M. Gorbenko, V. S. Paivin, and K. V. Savchenko for assistance in the experiments. 相似文献
97.
G. M. Koshkin 《Russian Physics Journal》1995,38(9):894-900
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 31–38, September, 1995. 相似文献
98.
V. F. Koshkin L. A. Luizova A. D. Khakhaev V. P. Chugin 《Journal of Applied Spectroscopy》1989,50(3):326-331
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 50, No. 3, pp. 511–518, March, 1989. 相似文献
99.
Sergiy Maksymenko 《Annals of Global Analysis and Geometry》2006,29(3):241-285
Let M be a smooth compact surface, orientable or not, with boundary or without it, P either the real line ℝ
1 or the circle S
1, and D(M) the group of diffeomorphisms of M acting on C^∞(M, P) by the rule h⋅ f = f ∘ h
−1 for h ∊ D(M) and f ∊ C^∞ (M,P). Let f: M → P be an arbitrary Morse mapping, Σ
f
the set of critical points of f, D(M,Σ
f
) the subgroup of D(M) preserving Σ
f
, and S(f), S (f,Σ
f
), O(f), and O(f,Σ
f
) the stabilizers and the orbits of f with respect to D(M) and D(M,Σ
f
). In fact S(f) = S(f,Σ
f
).In this paper we calculate the homotopy types of S(f), O(f) and O(f,Σ
f
). It is proved that except for few cases the connected components of S(f) and O(f,Σ
f
) are contractible, π
k
O(f) = π
k
M for k ≥ 3, π2 O(f) = 0, and π1 O(f) is an extension of π1 D(M) ⊕ Z
k
(for some k ≥ 0) with a (finite) subgroup of the group of automorphisms of the Kronrod-Reeb graph of f.We also generalize the methods of F. Sergeraert to give conditions for a finite codimension orbit of a tame smooth action of a tame Lie group on a tame Fréchet manifold to be a tame Fréchet manifold itself. In particular, we obtain that O(f) and O(f, Σ
f
) are tame Fréchet manifolds.
Communicated by Peter Michor Vienna
Mathematics Subject Classifications (2000): 37C05, 57S05, 57R45. 相似文献
100.
Cascade of coil-globule conformational transitions of single flexible polyelectrolyte molecules in poor solvent 总被引:1,自引:0,他引:1
Kiriy A Gorodyska G Minko S Jaeger W Stepánek P Stamm M 《Journal of the American Chemical Society》2002,124(45):13454-13462
We show that hydrophobic flexible polyelectrolyte molecules of poly(2-vinylpyridine) and poly(methacryloyloxyethyl dimethylbenzylammonium chloride) are trapped and frozen due to adsorption on the mica surface, and the observed AFM single molecule structures reflect the molecular conformation in solution. An increase of the ionic strength of the solution induces the cascade of abrupt conformational transitions due to the intrachain segregation from elongated coil to compact globule conformations through intermediate pearl necklace-globule conformations with different amounts of beads per chain. The length of the necklaces and the number of beads decrease, while the diameter of beads increases with the increase of ionic strength. Coexistence at the same time of extended coils, necklaces with different amounts of beads, and compact globules indicates the cascade of the first-order-type phase transitions. 相似文献