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1.
In the paper, we study the sufficient conditions for the lower-order coefficient of the parabolic equation
under which its solution satisfying the initial condition
stabilizes to zero, i.e., there exists the limit
uniform in x from every compact set K in ℝN for any function u 0(x) belonging to a certain uniqueness class of the problem considered and growing not rapidly than with a > 0 and b < 0 at infinity. __________ Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 12, No. 4, pp. 79–97, 2006.  相似文献   

2.
3.
The paper considers solutions of the coercive inequalities
defined on an arbitrary (possibly, unbounded) subset ℝ n , where n ≥ 2, L and are elliptic operators of the form
, and F is a certain function. __________ Translated from Sovremennaya Matematika. Fundamental'nye Napravleniya (Contemporary Mathematics. Fundamental Directions), Vol. 7, Partial Differential Equations, 2004.  相似文献   

4.
This article is a continuation of [J. Math. Sci., 99, No.5, 1541–1547 (2000)] devoted to the validity of the Lax formula (cited in the article of Crandall, Ishii, and Lions [Bull. AMS, 27, No.1, 1–67 (2000)])
for a solution to the Hamilton–Jacobi nonlinear partial differential equation
where the Cauchy data are now a function semicontinuous from below, is the usual norm in , , and is a positive evolution parameter. We proved that the Lax formula solves the Cauchy problem (2) at all points , fixed save for an exceptional set of points R of the F type, having zero Lebesgue measure. In addition, we formulate a similar Lax-type formula without proof for a solution to a new nonlinear equation of the Hamilton–Jacobi-type:
where is a diagonal positive-definite matrix, mentioned in Part I and having interesting applications in modern mathematical physics.  相似文献   

5.
Let be the class number of properly equivalent primitive binary quadratic forms of discriminant . The case of indefinite forms is considered. Assuming that the extended Riemann hypothesis for some fields of algebraic numbers holds, the following results are proved. 1. Let be an arbitrarily slow monotonically increasing function such that . Then
(\log p)^{\alpha (p)} } \right\} = o(\pi (x)),$$ " align="middle" vspace="20%" border="0">
where . 2. Let F be an arbitrary sufficiently large positive constant. Then for x_F$$ " align="middle" border="0"> , the relation
F} \right\} \asymp \frac{{\pi (x)}}{F}$$ " align="middle" vspace="20%" border="0">
holds. 3. The relation
holds, where A is Artin's constant. Hence, for the majority of discriminants of the form , where , the class numbers are small. This is consistent with the Gauss conjecture concerning the behavior of for the majority of discriminants 0$$ " align="middle" border="0"> in the general case. Bibliography: 22 titles.  相似文献   

6.
The paper deals with the problem of recovering the parameters (functions) and of the Maxwell dynamical system
(tan is the tangent component; is a solution) by the response operator ( is the normal). The parameters determine the velocity , the c-metric , and the time . It is shown that for any fixed , the operator determines and in uniquely. Bibliography: 15 titles.  相似文献   

7.
Let f(z) be a holomorphic Hecke eigenform of weight k with respect to SL(2, ) and let
denote the symmetric square L-function of f. A Voronoi type formula for
and the relation
are proved. Heuristic approaches to estimation of exponential sums arising in this connection are considered. Bibliography: 9 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 314, 2004, pp. 247–256.  相似文献   

8.
The paper considers the Pell equation
over the Fibonacci ∘-ring , which is obtained by supplying the ring of integers ℤ with the Fibonacci circle multiplication operation N ∘ M. It is proved that if a positive integer A satisfies the condition Aτ < [(A + 1)τ], where is the golden section, and [x] is the integral part of x, then the Pell equation is solvable both in integers and in positive integers N1 and N2. Moreover, for the number n(A; X) of integer solutions (N1, N2), |N1| ≤ X, lower bounds are established. Bibliography: 7 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 350, 2007, pp. 139–159.  相似文献   

9.
Let f(z) be a holomorphic Hecke eigencuspform of even weight k with respect to SL(2, Z) and let L(s, sym 2 f) = ∑ n=1 cnn−s, Re s > 1, be the symmetric square L-function associated with f. Represent the Riesz mean (ρ ≥ 0)
as the sum of the “residue function” Γ(ρ+1)−1 Ł(0, sym2f)xρ and the “error term”
. Using the Voronoi formula for Δρ(x;sym 2f), obtained earlier (see Zap. Nauchn. Semin. POMI. 314, 247–256 (2004)), the integral
is estimated. In this way, an asymptotics for 0 < ρ ≤ 1 and an upper bound for ρ = 0 are obtained. Also the existence of a limiting distribution for the function
, and, as a corollary, for the function
, is established. Bibliography: 12 titles. Dedicated to the 100th anniversary of G. M. Goluzin’s birthday __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 337, 2006, pp. 274–286.  相似文献   

10.
A power series with radius of convergence equal 1 is called a (p,A)-lacunary one if nk ≥ Akp, A > 0, 1 < p < ∞. It is proved that if 1 < p < 2 and f(x) is a (p,A)-lacunary series that satisfies the condition
, where
, for some ε > 0, then f ≡ 0. We construct a (p,A)-lacunary series f 0 such that
with a constant C0 = C0(p,A) > 0. Bibliography: 4 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 327, 2003, pp. 135–149.  相似文献   

11.
It is proved that under certain assumptions on the functions q(t) and f(t), there is one and only one function u0(t) ∈ at which the functional
attains its minimum. An error bound for the finite element method for computing the function u0(t) in terms of q(t), f(t), and the meshsize h is presented. Bibliography: 3 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 346, 2007, pp. 149–159.  相似文献   

12.
An analog of the classical Fourier formula for the characteristic function of a convex compact set is considered:
where W is a polyhedral in . Bibliography: 6 titles.  相似文献   

13.
In this paper, we consider the Kuramoto-Sivashinskii equation on the multidimensional torus with a Riemannian metric: where . For this equation the theorem on energy transfer holds. It is formulated in the following way. Let be the Fourier expansion of the function u. Denote by P N and P N the operators of rejection of the “leading” and, respectively, “lowest” terms of the Fourier expansion (harmonics), i.e., . For any ρ > 0,N ∈ ℕ, sn/2+5, and λ ∈ (0, 1), there exists R such that for any function. ϕ ∈ lying outside the ball in the ball , there exists an instant of time t ∈ (0, 1) such that g KS t ϕ=ψ and . Here, R is a constant depending on the metric (g), n s is the sth Sobolev norm, and is the C 1-norm. __________ Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 24, Dynamical Systems and Optimization, 2005.  相似文献   

14.
Using the integral operator that defines a solution of the Cauchy problem for the equation
we find an integral representation for solutions of the equation
in terms of arbitrary functions that are continuously differentiable sufficiently many times.  相似文献   

15.
Let M be either the space of 2π-periodic functions Lp, where 1 ≤ p < ∞, or C; let ωr(f, h) be the continuity modulus of order r of the function f, and let
, where
, be the generalized Jackson-Vallée-Poussin integral. Denote
. The paper studies the quantity Km(f − Dn,r,l(f)). The general results obtained are applicable to other approximation methods. Bibliography: 11 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 350, 2007, pp. 52–69.  相似文献   

16.
The following classes of functions analytic in the unit disk are considered:
and
where is the Nevanlinna characteristic and is a properly changing positive function on (0,1]. Necessary and sufficient conditions on are established under which the classes and are invariant under the operators of differentiation and integration. Bibliography: 7 titles.  相似文献   

17.
One considers the differential inequality
, where a j (x) are continuous functions, p* > 0, n ≥ 1, k > 1, and its special case
, where all r j (x) are sufficiently smooth positive functions. Uniform estimates are obtained for solutions defined in the same domain. __________ Translated from Trudy Seminara imeni I. G. Petrovskogo, No. 26, pp. 27–36, 2007.  相似文献   

18.
Let Λα be the analytic Holder class in the unit disk . For f ∈ Λα and , let Mf (I) = max I |f|. Assume that I and J are arcs such that |J| = 2|I| and J and I have the same midpoint. Then
It is proved that this estimate cannot be improved. Bibliography: 1 title. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 315, 2004, pp. 149–154.  相似文献   

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