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71.
Document image analysis: A primer 总被引:1,自引:0,他引:1
72.
V. V. Ruzhyts’kyi H. D. Tolstoluts’ka S. O. Karpov I. E. Kopanets’ H. M. Malyk 《Materials Science》2007,43(5):735-741
By the methods of thermal-desorption spectrometry and nuclear reactions, we study the processes of trapping, thermal desorption,
and evolution of the profiles of distribution of deuterium ionically implanted with an energy of 12 keV into Kh18N10T steel
at room temperature. The evolution of the microstructure of steel under the conditions of irradiation of samples with D2+ ions up to doses of 1 · 1018 D/m2−2 · 1022 D/m2 is studied by the method of electron microscopy. The regularities of changes in the mechanical properties of steel after
irradiation are determined.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 117–121, September–October, 2007. 相似文献
73.
74.
O. K. Kuvandikov E. U. Arzikulov A. I. Kovalev D. I. Tetel’baum 《Journal of Communications Technology and Electronics》2007,52(9):1054-1057
The effect of phosphorus impurities on the electronic structure of silicon single crystals and SiO2: Si nanocomposites is studied. The SiO2: Si structures with phosphorus impurities that are annealed over 2 h at a temperature of 1000°C exhibit an increase in the photoluminescence peak related to Si nanocrystals. The experimentally determined densities of states in the valence and conduction bands of SiO2: Si composites are in good agreement with the local electronic structure in the vicinity of silicon impurities that is calculated within the approximation of linear muffin-tin orbitals. 相似文献
75.
76.
V. P. Kuznetsov D. Yu. Remizov V. B. Shmagin K. E. Kudryavtsev V. N. Shabanov S. V. Obolensky O. V. Belova M. V. Kuznetsov A. V. Kornaukhov B. A. Andreev Z. F. Krasil’nik 《Semiconductors》2007,41(11):1312-1314
Results of experimental studies of erbium ion electroluminescence in p ++/n +/n-Si:Er/n ++ silicon diode structures grown by sublimation molecular-beam epitaxy are discussed. The distinctive feature of these structures is that the regions of electron flux formation of (n +-Si) and impact excitation of erbium ions (n-Si:Er) are spaced. The influence of the n +-Si layer thickness on electrical and electroluminescent properties of diodes was studied. It was shown that n +-Si layer thinning causes the transformation of the structure breakdown mechanism from tunneling to avalanche. The dependence of the Er3+ ion electroluminescence on the thickness of the heavily doped n +-Si region is bell-shaped. At the n +-Si-layer doping level n ≈ 2 × 1018 cm?3, the maximum electroluminescence intensity is attained at an n +-Si layer thickness of ~23 nm. 相似文献
77.
78.
79.
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
80.
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