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1.
A. A. Panov 《Mathematical Notes》1998,64(5):622-628
We estimate the number of periodic solutions for special classes ofnth-order ordinary differential equations with variable coefficients.
Translated fromMatematicheskie Zametki, Vol. 64, No. 5, pp. 720–727, November, 1998.
The author thanks Yu. S. Il'yashenko for setting the problems, permanent advice, and overall support. The author is also thankful
to D. A. Panov for numerous discussions.
This research was supported by the CRDF Foundation under grant MR1-220, by the INTAS Foundation under grant No. 93-05-07,
and by the Russian Foundation for Basic Research under grant No. 95-01-01258. 相似文献
2.
S. I. Mardaev 《Algebra and Logic》1999,38(5):319-325
For every modal positive operator, there exists a formula defining a least fixed point for that operator in partially ordered
Kripke models with the property of being cofinal for every infinite ascending chain. A similar result obtains also for strict
partially ordered Kripke models with the same property.
Supported by the Russian Humanitarian Science Foundation (RHSF), grant No. 97-03-04089, and by the Siberian Branch of the
Russian Academy of Science through PSO RAN No. 473, grant No. 3.
Translated fromAlgebra i Logika, Vol. 38, No. 5, pp. 585–597, September–October, 1999. 相似文献
3.
E. P. Krugova 《Mathematical Notes》1995,58(6):1294-1301
In this paper we consider convex measures on finite-dimensional spaces. We prove the differentiability of convex measures in the Skorokhod sense (and under some natural conditions, in the Fomin sense also). Simultaneously we give some additional results on differentiability of convex measures.Translated fromMatematicheskie Zametki, Vol. 58, No. 6, pp. 862–871, December, 1995.This research was partially supported by the Russian Foundation for Basic Research under grant No. 94-01-01556, by the Ministry of Science under grant No. M38300 and by the International Science Foundation under grant No. M38000. 相似文献
4.
We study the asymptotics of solutions to the Dirichlet problem for the heat equation in time-dependent domains with singular points.Translated fromMatematicheskie Zametki, Vol. 64, No. 2, pp. 163–179, August, 1998.This research was supported by the Russian Foundation for Basic Research under grant No. 96-01-00504 and by INTAS under grant No. 93-351. 相似文献
5.
V. A. Artamonov 《Mathematical Notes》1996,59(4):356-360
We describe the structure of finitely generated modules over general quantum Laurent polynomials and prove that Artin modules
over general quantum Laurent polynomials are cyclic.
Translated fromMatematicheskie Zametki, Vol. 59, No. 4, pp. 497–503, April, 1996.
This research was partially supported by the Russian Foundation for the Basic Research under grant No. 93-011-1544 and by
the INTAS program under grant No. 93-2618. 相似文献
6.
A. P. Buslaev 《Mathematical Notes》1996,59(3):234-240
The problem of the spectrum of a nonlinear system and its relation to ellipsoid transform widths are studied.Translated fromMatematicheskie Zametki, Vol. 59, No. 3, pp. 334–342, March, 1996.This research was partially supported by the Russian Foundation for Basic Research under grant No. 93-01-00237 and by the International Science Foundation under grant No. MP1000. 相似文献
7.
In this paper we consider an extremum problem for even periodic functions having small intervals as their supports and subject
to restrictions on the sum of the absolute values of their Fourier coefficients.
Translated fromMatematicheskie Zametki, Vol. 60, No. 3, pp. 323–332, September, 1996.
We wish to express our gratitude to S. B. Stechkin for his interest in our work.
This research was supported by the Russian Foundation for Basic Research under grant No. 96-01-00378, and the work of the
first and second authors also by the International Science Foundation under grant No. MC5300. 相似文献
8.
We consider quasistable multicriteria problems of discrete optimization on systems of subsets (trajectory problems). We single
out the class of problems for which new Pareto optima can appear, while other optima for the problems do not disappear when
the coefficients of the objective functions are slightly perturbed (in the Chebyshev metric). For the case of linear criteria
(MINSUM), we obtain a formula for calculating the quasistability radius of the problem.
Translated fromMatemalicheskie Zametki, Vol. 63, No. 1, pp. 21–27, January, 1998.
This research was supported by the Belarus Foundation for Basic Research under grant No. F95-70. 相似文献
9.
Rolando Cavazos-Cadena Emmanuel Fernández-Gaucherand 《Mathematical Methods of Operations Research》1995,41(1):89-108
We consider discrete-time nonlinear controlled stochastic systems, modeled by controlled Makov chains with denumerable state space and compact action space. The corresponding stochastic control problem of maximizing average rewards in the long-run is studied. Departing from the most common position which usesexpected values of rewards, we focus on a sample path analysis of the stream of states/rewards. Under a Lyapunov function condition, we show that stationary policies obtained from the average reward optimality equation are not only average reward optimal, but indeed sample path average reward optimal, for almost all sample paths.Research supported by a U.S.-México Collaborative Research Program funded by the National Science Foundation under grant NSF-INT 9201430, and by CONACyT-MEXICO.Partially supported by the MAXTOR Foundation for applied Probability and Statistics, under grant No. 01-01-56/04-93.Research partially supported by the Engineering Foundation under grant RI-A-93-10, and by a grant from the AT&T Foundation. 相似文献
10.
V. N. Temlyakov 《Mathematical Notes》1998,63(6):785-795
We investigate a generalization of width in the sense of Kolmogorov suitable for estimating bestm-term approximations. We generalize Carl's inequality which gives lower estimate of Kolmogorov widths in terms of entropy numbers. Application of these new inequalities gives some progress in the problem of estimating bestm-term trigonometric approximations of multivariate functions.Translated fromMatematicheskie Zametki, Vol. 63, No. 6, pp. 891–902, June, 1998.This research was supported by the National Science Foundation under grant No. DMS 9622925 and by the ONR foundation under grant No. N00014-96-1-1003. 相似文献
11.
A new method is proposed for finding asymptotics ast → ∞ of the solutions of the Cauchy problem for nonlinear evolution equations with nonsmall initial data.
Translated fromMatematicheskie Zametki, Vol. 59, No. 6, pp. 855–864, June, 1996.
This research was supported by the Russian Foundation for Basic Research under grant No. 93-011-134 and by the International
Science Foundation under grant No. BX000. 相似文献
12.
O. V. Besov 《Mathematical Notes》1998,64(3):303-315
We obtain sufficient conditions on a domainG ⊂ ℝn for functions defined onG to be extendable by zero to the entire space ℝn with smoothness preserved in an integral norm.
Translated fromMatematicheskie Zametki, Vol. 64, No. 3, pp. 351–365, September, 1998.
This research was supported by the Russian Foundation for Basic Research under grant No. 96-01-00243 and by program “Leading
Science Schools” under grant No. 96-15-96102. 相似文献
13.
S. Yu. Nemirovskii 《Mathematical Notes》1996,60(3):306-312
In the paper, we consider applications of strictly pseudoconvex domains to the problems of algebraicity and rationality. We
give a new proof of the Kodaira theorem on the algebraicity of a surface and we also prove a multidimensional version of this
theorem. Theorems analogous to the Hodge index theorem and the Lefschetz theorem about (1, 1)-classes are obtained for strictly
pseudoconvex domains. Conjectures on the geometry of strictly pseudoconvex domains on algebraic surfaces are formulated.
Translated fromMatematicheskie Zametki, Vol. 60, No. 3, pp. 414–422, September, 1996.
This research was supported by the Russian Foundation for Basic Research under grant No. 93-01-00225 and by the International
Science Foundation under grant No. 508. 相似文献
14.
Summary A general one dimensional change of variables formula is established for continuous semimartingales which extends the famous Meyer-Tanaka formula. The inspiration comes from an application arising in stochastic finance theory. For functions mapping
n
to , a general change of variables formula is established for arbitrary semimartingales, where the usualC
2 hypothesis is relaxed.Supported in part by NSF grant No. DMS-9103454Supported in part by John D. and Catherine T. MacArthur Foundation award for US-Chile Scientific CooperationSupported in part by FONDECYT, grant 92-0881 相似文献
15.
Infinite series of boundary conditions that are consistent with even-order higher symmetries and ensure the integrability
of a Burgers type equation are constructed.
Translated fromMatematicheskie Zametki, Vol. 60, No. 6, pp. 888–901, December, 1996.
This research was supported by the Russian Foundation for Basic Research under grant No. 93-011-16008 and by the International
Science Foundation under grant Nos. MLY00 and RK2000. 相似文献
16.
E. I. Yakovlev 《Mathematical Notes》1996,59(3):310-319
For gyro systems of relativistic type, we obtain solvability conditions for the two-point boundary value problem. We use the geodesic modeling method, in which the original problem is reduced to studying the existence of isotropic geodesic curves of the Kaluts-O. Klein Lorentz metric joining two fibers of a bundle over the configuration manifold of the system. As an example, we consider problems on the motion of charged test particles in an arbitrary electromagnetic field and in the outer Reissner-Nordstrem space-time in the field of a charged black hole and some external electromagnetic field.Translated fromMatematicheskie Zametki, Vol. 59, No. 3, pp. 437–449, March, 1996.This research was partially supported by the Russian Foundation for Basic Research under grant No. 94-01-00492a and by the International Science Foundation under grant No. NP4000. 相似文献
17.
A. G. Baskakov 《Mathematical Notes》1996,59(6):586-593
Associated with a family of evolution operators in a complex Banach space is a linear unbounded operator, which is studied
with the aid of a semigroup of difference operators and a difference operator in a sequence space. Some formulas for the spectra
of the linear operators in question (in particular, for abstract hyperbolic differential operators) and the spectrum mapping
theorem for the semigroup of difference operators are obtained.
Translated fromMatematicheskie Zametki, Vol. 59, No. 6, pp. 811–820, June, 1996.
This research was supported by the Russian Foundation for Basic Research under grant No. 95-01-00032 and by the International
Science Foundation under grant No. NZA000 and grant No. NZA300. 相似文献
18.
V. V. Kozlov 《Mathematical Notes》1995,58(3):938-947
Conditions are found for the existence of integral invariants of Hamiltonian systems. For two-degrees-of-freedom systems these
conditions are intimately related to the existence of nontrivial symmetry fields and multivalued integrals. Any integral invariant
of a geodesic flow on an analytic surface of genus greater than 1 is shown to be a constant multiple of the Poincaré-Cartan
invariant. Poincaré's conjecture that there are no additional integral invariants in the restricted three-body problem is
proved.
Translated fromMatematicheskie Zametki, Vol. 58, No. 3, pp. 379–393, September, 1995.
The work was financially supported by the Russian Foundation for Basic Research (grant No. 242 93-013-16244), International
Science Foundation (grant No. MCY 000), and INTAS (grant No. 93-339). 相似文献
19.
L. G. Kurakin 《Mathematical Notes》1998,63(4):503-508
Stability criteria of boundary equilibria for dynamical systems in the three critical cases, (n, k)=(3, 0), (2, 1), and (1, 1), are obtained.Translated fromMatematicheskie Zametki, Vol. 63, No. 4, pp. 572–578, April, 1998.The author wishes to thank V. I. Yudovich for useful discussions.This research was supported by the Russian Foundation for Basic Research under grant No. 96-01-01791 and by the International Science Foundation under grant NRQ000. 相似文献
20.
We give a complete classification of -invariant real hypersurfaces in complex two-plane Grassmannians G
2(C
m+2) with commuting normal Jacobi operator .
The first author was supported by MCYT-FEDER grant BFM 2001-2871-C04-01, the second author by grant Proj. No. KRF-2006-351-C00004
from Korea Research Foundation and the third author by grant Proj. No. R14-2002-003-01001-0 from Korea Research Foundation,
Korea 2006 and Proj. No. R17-2007-006-01000-0 from KOSEF. 相似文献