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91.
A. V. Govorkov A. Ya. Polyakov T. G. Yugova N. B. Smirnov E. A. Petrova M. V. Mezhennyi A. V. Markov I. -H. Lee S. J. Pearton 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(4):380-385
The relation between the density of etch pits revealed in GaN by etching in a KOH/NaOH eutectic and the density of dislocations determined by transmission electron microscopy (TEM) is studied along with the relation between the density of dislocations and the density of dark spot defects observed in GaN by microcathodoluminescence (MCL) and electron-beam-induced current (EBIC). It is demonstrated that selective etching is a reliable rapid method for the determination of the type and density of dislocations in GaN in the range 106–108 cm?2, while MCL and EBIC can be used for the rapid nondestructive determination of the density of dislocations in the range 106–108 cm?2. It is also found that some deep electron and hole traps are related to dislocations. 相似文献
92.
We present the results of a study and substantiation of the method of polygaussian approximation of an electrocardiographic (ECG) signal against interference background during computer analysis of that signal. It is proposed to use adaptive processing of ECG signals, which allows one to increase the signal-to-interference ratio by over 7 dB. 相似文献
93.
René Meziat Diego Patiño Pablo Pedregal 《Computational Optimization and Applications》2007,38(1):147-171
We propose an alternative method for computing effectively the solution of non-linear, fixed-terminal-time, optimal control
problems when they are given in Lagrange, Bolza or Mayer forms. This method works well when the nonlinearities in the control
variable can be expressed as polynomials. The essential of this proposal is the transformation of a non-linear, non-convex
optimal control problem into an equivalent optimal control problem with linear and convex structure. The method is based on
global optimization of polynomials by the method of moments. With this method we can determine either the existence or lacking
of minimizers. In addition, we can calculate generalized solutions when the original problem lacks of minimizers. We also
present the numerical schemes to solve several examples arising in science and technology. 相似文献
94.
95.
96.
Testing exponentiality against a class of alternatives which includes the RNBUE distributions based on the empirical laplace transform 总被引:1,自引:0,他引:1
S. G. Meintanis Ya. Yu. Nikitin A. V. Tchirina 《Journal of Mathematical Sciences》2007,145(2):4871-4879
A scale-free test for exponentiality is proposed which is consistent within an extended set of models, including, but not
limited to, the “renewal new better than used in expectation” (RNBUE) class of life distributions. The limiting null distribution of the test statistics is derived, and the approximate local
Bahadur efficiency is calculated for several families of alternatives. Finite-sample properties of the proposed procedures
are investigated via simulation. Bibliography: 24 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 339, 2006, pp. 63–77. 相似文献
97.
A. Ya. Braginskii 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(2):181-186
For the case of a phase transition into a macroscopically inhomogeneous state described by the order parameter (OP) that is characterized by a multiarm star of a vector {ki}, a method for compensating the spatial variation in all star arms ki is proposed. To this end, a unified tensor field (OP connectivity) is considered, which is interpreted as a stress field potential. The OP-connectivity interaction is described by the phenomenological dislocation charge. Alternative ways of physical interpretation of the OP connectivity are discussed. 相似文献
98.
99.
Ya. A. Éyubov 《International Applied Mechanics》1991,27(1):48-55
Azerbaidzhan Institute of Construction Engineering, Baku. Translated from Prikladnaya Mekhanika, Vol. 27, No. 1, pp. 55–64, January, 1991. 相似文献
100.
V. Ya. Popkova L. E. Vinogradova L. A. Leites V. K. Osmanov 《Russian Chemical Bulletin》1991,40(10):2075-2078
The reaction of ammonia with 2-chloroperfluoro-1-cyclohexene-1-thiocyanate leads to 2-amino-7-iminoperfluoro-4,5,6-trihydrobenzo-1,3-thiazole (II) due to intramolecular heterocyclization in the Thorpe reaction with the concurrent exoiminization. Analysis of the IR spectra of (II) in CCl4 and in the solid phase indicated that molecules of (II) in the crystal form hydrogen-bonded centrosymmetric dimers (D), which are in equilibrium with free molecules of (II) in solution.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2366–2370, October, 1991.The authors express their gratitude to D. I. Zagorevskii for taking the mass spectrum of (II) and to L. S. German for a useful discussion of this work. 相似文献