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91.
92.
An a posteriori (off-line) approach to the simultaneous detection and identification of quasi-periodic fragments in a numerical
sequence using their segments is analyzed. The solution of the problem is proposed for the case when the number of the desired
fragments is known. The following assumptions are made. (i) Each desired fragment of the numerical sequence coincides with
an element of the given alphabet of the reference sequences that have equal lengths (i.e., number of elements). (ii) Only
a segment (part) of the desired fragment can be processed; unprocessable parts of the fragment are interpreted as lost data.
(iii) The numbers of the elements in the sequence that correspond to the beginning of the desired fragment and the boundaries
of the segment in the fragment represent deterministic (rather than random) quantities; the boundaries of the segments are
different for different fragments; and the desired fragments are quasi-periodic in the sequence. (iv) Gaussian uncorrelated
noise impedes the observation of the sequence that contains quasi-periodic segments of the reference sequences. It is demonstrated
that the essence of the problem under study lies in the verification of a set of hypotheses on the mean value of a random
Gaussian vector (the power of this set exponentially increases with an increase in the dimension of the vector—the sequence
length). An effective a posteriori algorithm that provides for maximum-likelihood detection and identification is validated.
The estimates of the time and space complexity are related to the parameters of the problem. The results of the numerical
simulation are presented.
This work was supported by the Russian Foundation for Basic Research, project no. 03-01-00036 and 06-01-00058.
Aleksandr V. Kel’manov. Born April 25, 1952. Graduated from Izhevsk State Technical University in 1974. Received candidate’s degree in 1980 and
doctoral degree in 1994. Leading researcher of the Sobolev Institute of Mathematics, Siberian Division, Russian Academy of
Sciences. Scientific interests: mathematical methods for pattern recognition; discrete optimization; effective algorithms
for the analysis and recognition of random sequences; algorithms for the solution of applied problems; and methods and algorithms
for the processing, recognition, and synthesis of voice signals. Author of more than 120 papers.
Sergei A. Khamidullin. Born March 28, 1952. Graduated from Novosibirsk State University in 1974. Received candidate’s degree in 1997. Senior researcher
of the Sobolev Institute of Mathematics, Siberian Division, Russian Academy of Sciences. Scientific interests: mathematical
methods for pattern recognition; discrete optimization; effective algorithms for the analysis and recognition of random sequences;
algorithms for the solution of applied problems; and methods and algorithms for the processing, recognition, and synthesis
of voice signals. Author of more than 80 papers. 相似文献
93.
S. O. Shiryaeva A. I. Grigor’ev V. A. Koromyslov A. S. Golovanov 《Technical Physics Letters》2002,28(1):41-43
A dispersion equation for the capillary oscillations of a charged drop of incompressible liquid possessing a finite electric
conductivity is derived with an allowance for the energy lost as a result of the electromagnetic wave emission. The magnitude
of the electromagnetic radiation losses of the oscillating drop linearly increases with the electric conductivity and the
surface mobility of charge carriers. 相似文献
94.
A. A. Lebedev A. M. Strel’chuk D. V. Davydov N. S. Savkina A. N. Kuznetsov L. M. Sorokin 《Technical Physics Letters》2002,28(9):792-794
The electrical characteristics of (p)3C-SiC-(n)6H-SiC epitaxial heterostructures obtained by sublimation epitaxy in vacuum are studied. The band discontinuities are determined and the energy band diagram of the heterojunction is constructed. It is shown that the obtained heterostructure offers a promising material for high electron mobility transistors. 相似文献
95.
Yu. P. Pyt’ev I. I. Falomkin A. I. Chulichkov 《Pattern Recognition and Image Analysis》2006,16(3):523-528
A new method for compression of grayscale images containing a small number of graphical elements is proposed. The method is
characterized by high compression ratios, small losses, and good readability of the processed images. It is based on morphological
methods of image analysis and could be used to store images of documents produced by fax machines, scanners, etc.
Igor I. Falomkin. Born 1979. Graduated from the Faculty of Physics, Moscow State University, in 2001. Scientific interests: image analysis
and recognition, analysis and interpretation of experimental data. 相似文献
96.
O. E. Stepanov A. V. Bulanov V. E. Karnaukhov M. L. Lukashenko Yu. B. Vorob’ev 《Thermal Engineering》2006,53(9):699-705
We consider two procedures for evaluating the influence of nondensables on steam condensation taking into account the integral effect from interaction between the water-chemistry and thermal-hydrodynamic processes occurring in the primary coolant circuit of a nuclear power installation (NPI). Results from calculations of the passive safety system of an NPI are given. 相似文献
97.
V. P. Il’ina 《Glass and Ceramics》2007,64(9-10):318-321
Facing and decorative glass crystal materials were developed from mineral feedstock and technogenic wastes. The effect of the components present in the mineral feedstock in liquation and crystallization of the glasses was investigated. The materials obtained can be used in construction for facing walls. 相似文献
98.
V. D. Belik R. V. Litvin M. S. Koval’chenko 《Powder Metallurgy and Metal Ceramics》2006,45(11-12):593-598
The influence exerted by electric-spark spraying on the kinetics of mass transfer and the physicomechanical properties of coatings is investigated. It is shown that electric-spark spraying is determined by the dynamic properties of the cathode jets, which depend on the electrical parameters of the spark discharge, the size of the interelectrode interval, and the physical properties of the coatings, which vary during spraying. 相似文献
99.
Using ion exchange chromatography and an ATP-dependent actin precipitation step, we have isolated three myosin-I isozymes that, together, account for most of the K+EDTA-ATPase activity recovered from extracts of Dictyostelium. The two major myosin-I isozymes, present in approximately equal amounts, had apparent molecular masses of 125 kDa on SDS gels and have been identified by amino acid sequence analysis as the products of the Dictyostelium myosin-IB (DMIB) and myosin-ID (DMID) genes. DMIB, with a specific K+EDTA-ATPase activity 10-fold higher than DMID, was responsible for most of the activity in cell extracts. The third isozyme, present in low amounts, had an apparent molecular mass of 137 kDa on SDS gels and is too large to be the product of any of the known myosin-I genes. DMIB eluted from DE53 cellulose columns as two distinct peaks (II and III). Addition of the phosphatase inhibitor okadaic acid to the extraction buffer increased the fraction of DMIB recovered from growth phase cells in peak III from 35 to 70%. DMIB isolated from peak III, but not from peak II, displayed a significant level of actin-activated MgATPase activity. These results indicate that peak III represents a phosphorylated, actin-activatable form of DMIB. 相似文献
100.