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31.
Adaptive approximation (or interpolation) takes into account local variations in the behavior of the given function, adjusts
the approximant depending on it, and hence yields the smaller error of approximation. The question of constructing optimal
approximating spline for each function proved to be very hard. In fact, no polynomial time algorithm of adaptive spline approximation can be designed and no exact
formula for the optimal error of approximation can be given. Therefore, the next natural question would be to study the asymptotic
behavior of the error and construct asymptotically optimal sequences of partitions. In this paper we provide sharp asymptotic
estimates for the error of interpolation by splines on block partitions in
\mathbbRd{\mathbb{R}^d} . We consider various projection operators to define the interpolant and provide the analysis of the exact constant in the
asymptotics as well as its explicit form in certain cases. 相似文献
32.
Marco?Dozzi Yuriy?Kozachenko Yuliya?Mishura Kostiantyn?RalchenkoEmail authorView authors OrcID profile 《Statistical Inference for Stochastic Processes》2018,21(1):21-52
We construct the least-square estimator for the unknown drift parameter in the multifractional Ornstein–Uhlenbeck model and establish its strong consistency in the non-ergodic case. The proofs are based on the asymptotic bounds with probability 1 for the rate of the growth of the trajectories of multifractional Brownian motion (mBm) and of some other functionals of mBm, including increments and fractional derivatives. As the auxiliary results having independent interest, we produce the asymptotic bounds with probability 1 for the rate of the growth of the trajectories of the general Gaussian process and some functionals of it, in terms of the covariance function of its increments. 相似文献
33.
Yuliya A. Volkova Ekaterina M. Budynina Tamara S. Kuznetsova Nikolai S. Zefirov 《Tetrahedron》2008,64(16):3548-3553
A novel approach to acyclic alkyldinitronitronates using nucleophilic opening of epoxides with the trinitromethyl anion is presented. The scope and limitations of this synthetic procedure are presented. A series of highly functionalized 3,3-dinitroisoxazolidines were synthesized as mixtures of diastereomers. 相似文献
34.
D. Alde F. G. Binon M. Boutemeur C. Bricman A. V. Dolgopolov S. V. Donskov M. Gouanere S. Inaba A. V. Inyakin V. A. Kachanov G. V. Khaustov T. Kinashi E. A. Knapp M. Kobayashi A. A. Kondashov A. V. Kulik G. L. Landsberg A. A. Lednev V. A. Lishin T. Nakamura J. P. Peigneux S. A. Polovnikov V. A. Polyakov M. Poulet Yu. D. Prokoshkin S. A. Sadovsky V. D. Samoylenko P. M. Shagin A. V. Shtannikov A. V. Singovsky J. P. Stroot V. P. Sugonyaev K. Takamatsu T. Tsuru 《Zeitschrift fur Physik C Particles and Fields》1995,66(3):379-383
A partial-wave analysis of the ω ωπ0-system produced in the π- p→ωπ0 n reaction at 38 GeV/c beam momentum has been performed. A new 5?- meson state,ρ 5(22350), with a massM=2330±35 MeV and a width Γ=400±100 MeV, is observed. The analysis also confirms the 1?- ρ(2150) meson, a radial-orbital excitation of the ρ(770), observed earlier by the GAMS Collaboration. 相似文献
35.
Yuliya A. Kuznetsova Vladimir B. Romakh 《Applied biochemistry and biotechnology》1996,61(1-2):205-209
The prostaglandin H synthase (PGHS) reaction has been studied with syringaldazine as the electron donor. Kinetic parameters of the reaction agreed with those for commonly used electron donors. The sensitivity of the PGHS activity detection in the presence of syring aldazine increases 10 times. A sensitive spectrophotometric assay for polyunsaturated fatty acid (PUFA) detection using syringaldazine as a new electron donor has been proposed. 相似文献
36.
In the present paper we consider and study numerically two systems based on model FitzHugh–Nagumo neurons, where in the presence of periodic modulation of parameters it is possible to implement chaotic dynamics on the attractor in the form of a Smale–Williams solenoid in the stroboscopic Poincaré map. In particular, hyperbolic chaos characterized by structural stability occurs in a single neuron supplemented by a time-delay feedback loop with a quadratic nonlinear element. 相似文献
37.
38.
Marina Tikhonova Yuliya Kuzminova Xiaoying Fang Weiguo Wang Rustam Kaibyshev 《哲学杂志》2013,93(36):4181-4196
The effect of processing and annealing temperatures on the grain boundary characters in the ultrafine-grained structure of a 304-type austenitic stainless steel was studied. An S304H steel was subjected to multidirectional forging (MDF) at 500–800°C to total strains of ~4, followed by annealing at 800–1,000°C for 30 min. The MDF resulted in the formation of ultrafine-grained microstructures with mean grain sizes of 0.28–0.85 μm depending on the processing temperature. The annealing behaviour of the ultrafine-grained steel was characterized by the development of continuous post-dynamic recrystallization including a rapid recovery followed by a gradual grain growth. The post-dynamically recrystallized grain size depended on both the deformation temperature and the annealing temperature. The recrystallization kinetics was reduced with an increase in the temperature of the preceding deformation. The grain growth during post-dynamic recrystallization was accompanied by an increase in the fraction of Σ3n CSL boundaries, which was defined by a relative change in the grain size, i.e. a ratio of the annealed grain size to that evolved by preceding warm working (D/D0). The fraction of Σ3n CSL boundaries sharply rose to approximately 0.5 in the range of D/D0 from 1 to 5, which can be considered as early stage of continuous post-dynamic recrystallization. Then, the rate of increase in the fraction of Σ3n CSL boundaries slowed down significantly in the range of D/D0 > 5. A fivefold increase in the grain size by annealing is a necessary condition to obtain approximately 50% Σ3n CSL boundaries in the recrystallized microstructure. 相似文献
39.
Yuliya S. Rozhkova Irina V. Plekhanova Alexey A. Gorbunov Olga G. Stryapunina Evgeny N. Chulakov Victor P. Krasnov Marina A. Ezhikova Mikhail I. Kodess Pavel A. Slepukhin Yurii V. Shklyaev 《Tetrahedron letters》2019,60(11):768-772
A new approach for the synthesis of functionalized racemic 3,4-dihydroferroceno[c]pyridines via the Ritter reaction of 2-methyl-1-ferrocenylpropan-1-ol with nitriles in the presence of methansulfonic acid was developed. The scope and limitations of the reaction were evaluated. Selected racemic 3,4-dihydroferroceno[c]pyridines were successfully separated by preparative HPLC on a Chiralcel OD-H column. The absolute configuration of the enantiomers was determined by X-ray crystal structure analysis. 相似文献
40.
Gimranov Dmitriy R. Abdullina Aisylu F. Sevast’yanova Ekaterina V. Petrova Yuliya Yu. 《平面色谱法杂志一现代薄层色谱法》2015,28(5):343-351
JPC – Journal of Planar Chromatography – Modern TLC - The thin-layer chromatography (TLC) procedures of metal cations, modified with amines and cationic surfactant micelles, followed by... 相似文献