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991.
Vadim Azhmyakov Vladimir Boltyanski 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(2):1110-1119
The aim of this paper is to extend the dynamic programming (DP) approach to multi-model optimal control problems (OCPs). We deal with robust optimization of multi-model control systems and are particularly interested in the Hamilton-Jacobi-Bellman (HJB) equation for the above class of problems. In this paper, we study a variant of the HJB for multi-model OCPs and examine the natural relationship between the Bellman DP techniques and the Robust Maximum Principle (MP). Moreover, we describe how to carry out the practical calculations in the context of multi-model LQ-problems and derive the associated Riccati-type equation. 相似文献
992.
Vladimir Ja?imovi? 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(8):2426-2432
Sufficient conditions of bifurcation stated in Arutyunov et al. (2009) [5] are investigated in order to reconsider celebrated Hopf bifurcation as the simplest bifurcation of Fredholm operators of zero index. In several examples abstract result is applied to both finite and infinite dynamical systems exhibiting classical Hopf bifurcation as well as double Hopf bifurcation. 相似文献
993.
O. A. Morozov A. K. Naumov S. L. Korableva D. I. Tselishchev 《Optics and Spectroscopy》2013,114(6):827-830
A procedure using a spectrometer with a CCD detector for interpreting the luminescence lines caused by ordinary and cross-relaxation transitions is presented for LaF3 crystal activated by Pr3+ ions as example. 相似文献
994.
Olena I. Lukashuk Kostyantyn M. Kondratyuk Alexandr V. Golovchenko Vladimir S. Brovarets Valery P. Kukhar 《Heteroatom Chemistry》2013,24(4):289-297
It has been shown that the derivatives of diethyl 5‐amino‐2‐phthalimidoalkyl‐1,3‐oxazol‐4‐ylphosphonates can be employed in the synthesis of phosphorylated peptidomimetics containing the phosphonoglycine residue. The reaction of diethyl 5‐alkylamino‐2‐aminoalkyl‐1,3‐oxazol‐4‐ylphosphonates with unsaturated azlactones was utilized to obtain phosphorylated peptidomimetics with dehydroamino acid moieties. The double bond in the latter was reduced with zinc in acetic acid to provide the corresponding saturated peptidomimetics containing a diethoxyphosphoryl group in the side chain. 相似文献
995.
Andrew Kuttler Sravanthi Durganala Albert Fratini Alexander B. Morgan Vladimir Benin 《Heteroatom Chemistry》2013,24(5):361-371
The present report describes the X‐ray structural and theoretical studies of some new pinacolboronate esters, and it also outlines the use of the target structures in Suzuki coupling reactions to produce new aromatic or heteroaromatic esters and amides. X‐ray structural analysis of the studied compounds revealed that the pinacolborane ring's position with respect to the benzene ring varies, depending on the particular environment. An ortho‐positioned carboxylic ester (methyl ester) causes a nearly perpendicular orientation of the pinacolborane unit with respect to the benzene ring, whereas an ortho‐positioned amide (N,N‐dimethylamide) causes the pinacolborane unit to orient itself nearly coplanar. A plausible explanation has been provided, based on both steric and electronic factors. 相似文献
996.
Ilyas S. Nizamov Farid D. Yambushev Ilnar D. Nizamov Alexandra D. Voloshina Vladimir A. Alfonsov 《Heteroatom Chemistry》2013,24(1):36-42
The Kabachnik–Fields reaction of E,Z‐citral with diethyl phosphite in the presence of isobutylamine has been found to form α‐aminophosphonates. The Pudovik reactions of diethyl phosphite with prenyl imines prepared on the basis of E,Z‐citral with isobutylamine also allowed us to obtain the same α‐aminophosphonates. We have managed to synthesize α‐aminophosphonates by the reaction of O,O‐dialkyl trimethylsilyl phosphites with prenyl imines in the presence of water or diethylamine. α‐Aminophosphonates were also synthesized by the reaction of diethyl phosphite with (R,S)‐citronellal in the presence of alkylamines. α‐Aminophosphonates obtained showed bacteriostatic activity against Staphylococcus aureus and Bacillus cereus. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 24:36–42, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21060 相似文献
997.
Illia Krasnou Elena Melenevskaya Alexander Filippov Vladimir Aseyev Sami Hietala 《Journal of Macromolecular Science: Physics》2013,52(3):500-510
Aqueous solutions of complexes formed between poly(vinylpyrrolidone) (PVP), as a matrix polymer, and fullerene C60 were investigated. The effect of the external hydrodynamic field on the supermolecular assemblies formed by the complexes was analyzed. Despite the low content in the complexes (1.5 mass%), fullerene significantly modified the viscosity of aqueous PVP. Thus, the dynamic viscosity of the PVP/C60 complexes grew faster than that of the pure PVP upon increasing the PVP/C60 concentration. The difference in viscosities is especially pronounced for semidilute solutions. As a possible explanation, it is assumed that fullerenes act as crosslinks, in addition to the physical entanglements of the PVP macromolecules, which appear in the vicinity of the crossover concentration. Shear flow corresponding to the high shear rates destroyed fullerene‐induced intermolecular crosslinks in PVP/C60 solutions. 相似文献
998.
Formation of reverse micelles in the water–hexane–AOT system has been investigated by molecular dynamics simulations. In order to optimize calculation strategy, the starting spatial disposition of components was assumed to be random. Such an approach was found to provide a lower dependence of final results on initial conditions as compared to the calculations using pre-assembled reverse micelles as a starting geometry. The calculated structural parameters of reverse micelles (such as their shape, size, and distribution of components) were found to agree with the available experimental data. 相似文献
999.
Vladimir F. Zadorozhny 《Applicable analysis》2013,92(3):529-537
By using the well-known Friedrichs extension and some a priori inequality, we obtain weak solutions of a Lyapunov equation. In particular, we show that the Lyapunov functions satisfying necessary and sufficient conditions in the domain of asymptotic stability of a singular point some dynamical system must be absolutely continuous. 相似文献
1000.
In this paper we study what planar graphs are “rigid” enough such that they can not be drawn on the plane with few (1, 2, or 3) crossings per edge. A graph drawn on the plane is k-immersed in the plane if each edge is crossed by at most k other edges. By a proper k-immersion of a graph we mean a k-immersion of the graph in the plane such that there is at least one crossing point. We give a characterization (in terms of forbidden subgraphs) of 4-connected graphs which triangulate the plane and have a proper 1-immersion. We show that every planar graph has a proper 3-immersion. 相似文献