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1.
2.
P. N. Sapozhnikov 《Journal of Mathematical Sciences》1991,53(6):578-582
An analog of a sufficient statistic is proposed in the finite-dimensional linear space of statistics. It is shown that the unbiased estimator of the linear function of a parameter closest to a given function, expressed in terms of a minimal linearly sufficient statistic, is potentially unbiased and optimal.Translated from Statisticheskie Metody Otsenivaniya i Proverki Gipotez, pp. 51–58, 1986. 相似文献
3.
We consider an M/G/1 queue with symmetric service discipline. The class of symmetric service disciplines contains, in particular, the preemptive
last-come-first-served discipline and the processor-sharing discipline. It has been conjectured in Kella et al. [1] that the
marginal distribution of the queue length at any time is identical for all symmetric disciplines if the queue starts empty.
In this paper we show that this conjecture is true if service requirements have an Erlang distribution. We also show by a
counterexample, involving the hyperexponential distribution, that the conjecture is generally not true.
AMS Subject Classifications Primary—60K25; Secondary—90B22 相似文献
4.
5.
Yu.A. Danilov V.P. Lesnikov Yu.N. Nozdrin V.V. Podolskii M.V. Sapozhnikov O.V. Vikhrova B.N. Zvonkov 《Journal of magnetism and magnetic materials》2006
The properties of Mn-doped GaAs layers grown by laser deposition were investigated with measurements of Hall effect and magneto-optical Kerr effect (MOKE). The electrical and magnetic parameters of the layers were defined by growth temperature and quantity of sputtered Mn. It was shown that room-temperature ferromagnetism is revealed by MOKE and, after ruby laser 25 ns pulse annealing, by Hall effect measurements. 相似文献
6.
Feoktistova L. P. Sapozhnikov A. N. Aleksandrova G. P. Medvedeva S. A. Grishchenko L. A. 《Russian Journal of Applied Chemistry》2002,75(12):1911-1915
Iron-containing derivatives of arabinogalactan (ferroarabinogalactans) were subjected to X-ray diffraction analysis to determine the form and structure of bound iron. Crystal lattice parameters a of the iron-containing phase were measured and the average crystallite size was determined. 相似文献
7.
L. A. Grishchenko S. A. Medvedeva G. P. Aleksandrova L. P. Feoktistova A. N. Sapozhnikov B. G. Sukhov B. A. Trofimov 《Russian Journal of General Chemistry》2006,76(7):1111-1116
Formation of silver nanoparticles in the course of chemical reduction of AgNO3 with arabinogalactan in aqueous alkaline solution was studied by electronic absorption spectroscopy and X-ray diffraction analysis. The pH of the solution was found to be the major factor affecting the degree of reduction of Ag+ ions. The probable reaction mechanism was discussed. Composites containing up to 58% Ag, with the metal particle size of 7–16 nm, were prepared. The nanoparticle size can be controlled by varying the reactant ratio AgNO3: arabinogalactan. Chemical modification of arabinogalactan was confirmed by IR and 13C NMR spectroscopy and by TLC. 相似文献
8.
A. A. Abramov N. V. Averina B. Z. Iofa V. V. Samoshin N. A. Ivanova Yu. A. Sapozhnikov N. S. Zefirov 《Chemistry of Heterocyclic Compounds》1997,33(8):982-985
A study was carried out on the extraction of strontium(II) and lead(II) picrates by chloroform solutions of crown and dithiacrown ethers. The benzene ring substituents in benzodithia-18-crown-6 only slightly affect the extraction of strontium and lead cations and their separation. The introduction of an adamantyl group onto the benzene ring markedly increases the extraction of lead and the separation selectivity of these cations. The use of dithia derivatives of benzo-18-crown-6 is less efficient for the extraction of both strontium and lead, though the selectivity of their separation is almost the same as in the extraction with benzo-18-crown-6.M. V. Lomonosov Moscow State University, 119899 Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1125–1129, August, 1997. 相似文献
9.
N. A. Tyukavkina N. N. Pogodaeva E. I. Brodskaya Yu. M. Sapozhnikov 《Chemistry of Natural Compounds》1976,11(5):613-616
Summary 1. The peculiarities of the properties of 3-hydroxyflavone are due to the fact that the introduction of the proton-donating hydroxy group directly into the heterocycle leads to an increase in the aromaticity of the pyrone fragment through the stabilization of a pyrylium structure.2. The causes of the decreased acidity and basicity of 5-hydroxyflavone are the formation of an intramolecular hydrogen bond of the chelate type and a disturbance of the coplanarity of the molecule. The combination of these factors explains the anomalously high position of the band of the stretching vibrations of the carbonyl group of this compound.Irkutsk Institute of Organic Chemistry, Siberian Branch of the Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 583–587, September–October, 1975. 相似文献
10.
Rare annihilation reactions for stopped antiprotons in deuterium ¯pdMN; M, whereM stands for, or other heavy mesons, are considered using the two-step model described by the triangle diagram. It was found that the probabilities of these processes are comparable with those for ¯pd–
p. The study of all Pontecorvo reactions is very important for the goals of meson spectroscopy as well as for understanding the high momentum components of the deuteron wave function.Dedicated to the memory of M. Gmitro.We would like to thanks P. P. Temnikov who brings our attention to the necessity of considering the reactions (7). We have benefited also from many discussions with C. Guaraldo, D. E. Kharzeev and L. A. Kondratyuk on these topics. 相似文献