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141.
Section 1 presents the main questions associated with the application of the algebraic approach to pattern recognition and classification. The answers to these questions constitute a problem-oriented theory of this application domain. In Sections 2 and 3, the listed questions are used to construct a solvability theory for the design of trend-identification algorithms. We formally describe the initial information set (algorithm inputs), the final information set (algorithm outputs), the precedents, and the additional constraints. Solvability and regularity criteria are derived for the problem of construction of trend-identification algorithms. 相似文献
142.
A. G. Rudakov 《Journal of Mathematical Sciences》2003,117(1):3878-3889
Relationship is established between some periods in the history of seismic prospecting and the changes in the understanding of its physical and geological foundations. Particular attention is given to the influence of the technological progress in seismic data processing on the change in the understanding of the structure and composition of a medium. Bibliography: 46 titles. 相似文献
143.
Tetraiodo-1,2-dicarba-closo-dodecaborane and 9-bromo-8,10,12-triiodo-1,2-dicarba-closo-dodecaborane were synthesized by oxidative iodination of 1,2-dicarba-closo-dodecaborane and 9-bromo-1,2-dicarba-closo-dodecaborane, respectively, in AcOH using a mixture of nitric and sulfuric acid as an oxidant of iodine. The intermediates
in the ortho-carborane iodination were identified. By the action of elemental bromine on 9-iodo-1,2-dicarba-closo-dodecaborane in the presence of aluminum chloride catalyst 9-iodo-8,10,12-tribromo-1,2-dicarba-closo-dodecaborane was obtained. Deborination of the synthesized substances with an alcohol solution of KOH led to formation of
1,5,6,10-tetraiodo-5-bromo-1,6,10-triiodo- and 5-iodo-1,6,10-tribromo-7,8-dicarbaundecaborates methylammonium salts. 相似文献
144.
145.
Doklady Mathematics - An approach is proposed to consider heuristic metrics introduced and used in data analysis problems. In the approach, the entire information on pairwise distances expressed by... 相似文献
146.
O. B. Rudakov L. V. Rudakova E. A. Podolina L. G. Barsukova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(11):1972-1975
Penetration isotherms ψ of eight binary solvent systems used as mobile phases in liquid chromatography are calculated. Dependences
of penetrability coefficients of binary mixtures on the volume fraction of the more active solvent are described using modified
polynomial functions, in which some empirical coefficients are changed for penetrability coefficients of pure solvents. 相似文献
147.
The early stages of the ring opening reaction of 1,3-cyclohexadiene to form its isomer 1,3,5-hexatriene, upon excitation to the ultrashort-lived 1 1B2 state, were explored. A series of one-color two-photon ionization/photoelectron spectra reveal a prominent vibrational progression with a frequency of 1350 cm(-1), which is interpreted in a dynamical picture as resulting from the ultrafast wave packet dynamics associated with the ring opening reaction. Photoionization in two-color three-photon and one-color four-photon ionization schemes show an ionization pathway via the same ultrashort-lived 1 1B2 state, and in addition, a series of Rydberg states with quantum defects of 0.93, 0.76, and 0.15, respectively. Using those Rydberg states as probes for the reaction dynamics in a time-resolved pump-probe experiment provides a direct observation of the elusive 2 1A1 state that has been implicated as an intermediate step between the initially excited 1 1B2 state and the ground electronic state. The rise and decay times for the 2 1A1 state were found to be 55 and 84 fs, respectively. 相似文献
148.
This is a study of the cross-polarization effects in the case of 14N quadrupolar spin-system with a long spin-lattice relaxation time. Two important benefits of the cross-polarization technique were demonstrated for PETN: (i) a polarization transfer resulting in increased NQR single shot signal response and (ii) a dynamic reduction in recovery time of the NQR system allowing scan repetition on a much shorter timescale. It was proved that this technique can reduce the optimal waiting time between pulse sequences up to 60 times through a significant reduction of the relaxation time of the quadrupolar spin-system. All experiments were carried out at room temperature using spin-locking multi-pulse sequences and small external magnetic field. 相似文献
149.
V. V. Ovcharov V. I. Rudakov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2009,3(4):639-643
The influence of fluxes of intrinsic nonequilibrium semiconductor defects on impurity diffusion in a nonuniform temperature field is considered in the framework of the phenomenological theory of irreversible processes. The mass transfer coefficient defined as the ratio of the concentrations of nonequilibrium and equilibrium defects is introduced to take the excessive concentration of nonequilibrium defects into account. The introduction of this coefficient into equations for matter and heat fluxes makes it possible to express the parameters of the process of thermal diffusion (the diffusion coefficient and the heat of transport) as a time-dependent function of the excessive concentration of intrinsic nonequilibrium semiconductor defects. 相似文献
150.
V. F. Bykovsky A. G. Kobets Y. V. Korotaev I. N. Meshkov A. Yu. Rudakov V. N. Pavlov R. V. Pivin G. V. Trubnikov S. L. Yakovenko 《Physics of Particles and Nuclei Letters》2008,5(7):577-578
The low energy positron injector for the Low Energy Particle Toroidal Accumulator (LEPTA) accumulator was assembled at the
Joint Institute for Nuclear Research (JINR). Key elements of the injector have been tested. The cryogenic source of slow positrons
was tested with a test isotope 22Na of the initial activity of 0.8 MBk. A continuous slow positron beam intensity of 5.8 × 103 particle per second with an average energy of 1.2 eV and a spectrum width of 1 eV has been obtained. The achieved moderator
efficiency is about 1%. The accumulation process in the positron trap was investigated with electron flux. The lifetime of
the electrons in the trap, τlife ≥ 80 s and capture efficiency ɛ ∼ 0.4, were obtained. The maximum number of accumulated particles was N
exper = 2 × 108 at the initial flux of 5 × 106 electrons s−1.
The text was submitted by the authors in English. 相似文献