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91.
A. V. Kalashnikov V. A. Kostenko 《Moscow University Computational Mathematics and Cybernetics》2008,32(3):177-181
Iterative multiprocessor scheduling algorithms are considered. The iterative algorithms make it possible to solve scheduling problems for a wide class of computer architectures but are very intricate from the computational point of view. To simplify the iterative algorithms, we propose an approach to their construction based on the subdivision of the space of correct schedules into disjoint domains, namely, an algorithm for constructing domains is proposed, the operations of the schedule transformations closed within the domains are introduced, and a technique for cutting off domains is developed. The approach developed also makes it possible to construct parallel algorithms with a low traffic of the exchange between parallel processes. 相似文献
92.
Let ξt be a regenerative process and assume that, at each state x, the process can fail with intensity α(x). If the inter-regeneration
times have a finite exponential moment orinf
xα(x)>0, then α(ξt) tends to some limiting positive intensity as t→∞ (under mild additional restrictions). This fact is widely used in engineering
because the limiting intensity can be employed in various calculations, say, in reliability theory. The paper contains a variety
of examples showing that α(ξt) provided that inter-regeneration time has no exponential moment andinf
x α(x)=0. The speed of convergence depends, in general, on both the tail of inter-regeneration time and α(x).
Proceedings of the Seminar on Stability Problems for Stochastic Models, Hajdúszoboszló, Hungary, 1997, Part III. 相似文献
93.
V. V. Kalashnikov 《Journal of Mathematical Sciences》1999,94(4):1558-1563
The goal of the paper is to clarify whether the nondegenerate Hamiltinian systems are “typical” among all integrable systems.
The importance of this problem is emphasized by a theorem of Fomenko-Zieschang, in which an isoenergy invariant determining
the nondegenerate systems up to topological equivalence is constructed. Bibliography: 12 titles.
Published inZapiski Nauchnykh Seminarov POMI, Vol. 234, 1996, pp. 184–192. 相似文献
94.
I. L. Buchbinder O. K. Kalashnikov I. L. Shapiro V. B. Vologodsky J. J. Wolfengaut 《Fortschritte der Physik》1989,37(3):207-223
The grand unified theory (GUT) based on the O(N) and SU(N)-gauge groups after the conformally invariant gravity being included is investigated. We calculate the one-loop gravity contributions into the renormalization group equations and study their solutions. The analysis performed show that the asymptotic freedom behaviour early established for all GUT's coupling constants is not broken by taking into account this kind of gravity. However all restrictions imposed on the GUT multiplet composition become less firmly and the physical content of the constructed models is more realistic. 相似文献
95.
Queuing models described as regenerative processes driven by several sequences are under investigation. Occurrence times in these sequences are supposed to be asynchronous, in general. Sensitivity coefficients that are derivatives of some stationary performance measures with respect to definite parameters as well as derivatives of higher orders are derived for such queuing models. These sensitivity coefficients can be evaluated by simulation. 相似文献
96.
K. Goetz M. Dick M. P. Kalashnikov A. M. Maksimchuk Yu. A. Mikhailov A. V. Rode G. V. Sklizkov I. Uschman E. Forster 《Journal of Russian Laser Research》1990,11(4):321-342
The paper describes an investigation of the characteristics of spherical focusing Bragg-reflection mirrors. The integral reflectivity of bent crystals at Bragg angles 80–90°, the width of the spectrum of the reflected x-rays, and the spatial resolution of the images formed by the focusing crystals are considered. Results are presented of the calculated integral reflectivity of bent silicon and quartz crystals of different orientation and in different orders of reflection. The feasibility is demonstrated of laser-plasma diagnostics using the images obtained with the aid of a multichannel x-ray microscope based on focusing crystals. Possible schemes of active diagnostics of a dense laser plasma using a monochromatic transilluminating x-ray beam are considered.Laser Plasma Laboratory, Lebedev Physics Institute. Translated from FIAN Preprint No. 143, Lebedev Physics Institute of the Academy of Sciences of the USSR, Moscow, 1989. 相似文献
97.
Infrared supercontinuum from a large mode area PCF under extreme picosecond excitation 总被引:1,自引:0,他引:1
V. G. Savitski K. V. Yumashev V. L. Kalashnikov V. S. Shevandin K. V. Dukel’skii 《Optical and Quantum Electronics》2007,39(15):1297-1309
Evolution of the long-wavelength edge of supercontinuum (SC) in a large mode-area photonic crystal fiber (LMA PCF) under extreme
(close to the fiber damage threshold) picosecond excitation is analyzed for the first time to our knowledge. The obtained
results are interpreted on the basis of the numerical simulations explaining both spectral and temporal characteristics of
SC in dependence on the pulse power and the fiber length. An existence of the minimum LMA PCF length providing the broadest
spectrum under the highest picosecond excitations is predicted. The multimode cross-modulation inside the LMA PCF is analyzed,
as well.
相似文献
98.
An experimental setup for studying optical materials under the action of plasma-emitted intense (up to 105 W/cm2) ultraviolet and vacuum ultraviolet radiation is described, and methods for estimating the radiation damage are developed. The damage produced in calcium fluoride ionic crystals at ~300 K by low (103 rad) and moderate (106 rad) absorbed doses is experimentally estimated. 相似文献
99.
V.G.?SavitskiEmail author A.M.?Malyarevich K.V.?Yumashev V.L.?Kalashnikov B.D.?Sinclair H.?Raaben A.A.?Zhilin 《Applied physics. B, Lasers and optics》2004,79(3):315-319
A diode-pumped 1.34 m Nd:YVO4 laser passively Q-switched with PbS quantum dots doped glass is presented. An average output power of 24 mW with a Q-switching efficiency of 13% and a Q-switched pulse width of 15 ns was obtained. A four level spectroscopic model of a PbS quantum dots doped glass saturable absorber is applied to numerically simulate passively Q-switched Nd:YVO4 laser operation. It has been shown that for the simulation of passive Q-switching of 1.3 m Nd:YVO4 lasers with PbS doped glasses as the saturable absorbers, it is necessary to take into account intensity dependence of bleaching relaxation times. PACS 42.60.Gd; 42.55.Xi; 42.70.Hj 相似文献
100.
S. Naumov E. Sorokin V.L. Kalashnikov G. Tempea I.T. Sorokina 《Applied physics. B, Lasers and optics》2003,76(1):1-11
We report stable self-starting near-transform-limited 26-fs pulses at 250-mW output power from a Kerr-lens mode-locked (KLM)
Cr4+:YAG laser using chirped mirrors in combination with prisms. The highest output power achieved in KLM regime was 600 mW at
55-fs pulse duration. The experimental results agree well with the results of theoretical analysis with respect to KLM self-starting
ability and stability against continuous-wave and multi-pulse operation. Parameter ranges for stable transform-limited KLM
pulses as well as the shortest achievable pulse durations are established. Using an InGaAs-InP semiconductor saturable absorber
mirror we could obtain self-starting 57-fs pulses at the average output power of 200 mW. Two-photon absorption was found to
be the main mechanism favoring the multiple-pulse operation.
Received: 2 May 2002 / Revised version: 16 July 2002 / Published online: 8 January 2003
RID="*"
ID="*"Corresponding author. Fax: +43-1/58801-38799, E-mail: sorokina@tuwien.ac.at 相似文献