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91.
Henrik L. Pedersen 《Mediterranean Journal of Mathematics》2007,4(4):419-433
We show that the remainder in Ruijsenaars’ asymptotic expansion of the logarithm of Barnes double gamma function gives rise
to a completely monotone function. Fourier expansions of the multiple Bernoulli polynomials are also obtained.
Research supported by the Carlsberg Foundation. 相似文献
92.
Diderik Batens 《Logica Universalis》2007,1(1):221-242
In this paper, adaptive logics are studied from the viewpoint of universal logic (in the sense of the study of common structures
of logics). The common structure of a large set of adaptive logics is described. It is shown that this structure determines
the proof theory as well as the semantics of the adaptive logics, and moreover that most properties of the logics can be proved
by relying solely on the structure, viz. without invoking any specific properties of the logics themselves. 相似文献
93.
Smooth Solutions to Optimal Investment Models with Stochastic Volatilities and Portfolio Constraints
Pham 《Applied Mathematics and Optimization》2002,46(1):55-78
Abstract. This paper deals with an extension of Merton's optimal investment problem to a multidimensional model with stochastic volatility
and portfolio constraints. The classical dynamic programming approach leads to a characterization of the value function as
a viscosity solution of the highly nonlinear associated Bellman equation. A logarithmic transformation expresses the value
function in terms of the solution to a semilinear parabolic equation with quadratic growth on the derivative term. Using a
stochastic control representation and some approximations, we prove the existence of a smooth solution to this semilinear
equation. An optimal portfolio is shown to exist, and is expressed in terms of the classical solution to this semilinear equation.
This reduction is useful for studying numerical schemes for both the value function and the optimal portfolio. We illustrate
our results with several examples of stochastic volatility models popular in the financial literature. 相似文献
94.
Sergio Albeverio Volodymyr Koshmanenko Mykola Pratsiovytyi Grygoriy Torbin 《Positivity》2006,10(1):39-49
We introduce the conflict interaction with two positions between a couple of image probability measures and consider the associated
dynamical system. We prove the existence of invariant limiting measures and find the criteria for these measures to be a pure
point, absolutely continuous, or singular cotinuous as well as to have any topological type and arbitary Hausdorff dimension. 相似文献
95.
Moessbauer studies on the effect of substitution with 3% Al, Co, Mn atoms in the intermetallic compound of Hf0.8Ta0.2Fe2 are reported. The Al substitution leads to increase of the FM-AFM transition temperature and to decrease of the AFM-PM transition temperature. The Co substitution leads to disappearance of the FM state, only showing some FM impurity component, while Mn substituted compound indicates coexistence of FM and AFM states at low temperature. The phenomena imply complex itinerant electron properties in these magnetic systems. 相似文献
96.
In this paper, we prove a sharpening of large deviation for increments of Brownian motion in (p,r)-capacity and Hölder norm case. As an application, we obtain a functional modulus of continuity for (p,r)-capacity in the stronger topology. 相似文献
97.
Christophe Cuny 《Journal of multivariate analysis》2006,97(8):1842-1869
Let (Xm,n)(m,n)∈Z2 be a Cp-valued wide sense stationary process. We study the prediction theory of such processes according to different total orders on Z2. In the case of a “rational order”, we give the spectral distribution of the resulting evanescent component and prove that for two different rational orders, the resulting evanescent components are mutually orthogonal. 相似文献
98.
Armen Shirikyan 《Probability Theory and Related Fields》2006,134(2):215-247
We consider a class of dissipative PDE's perturbed by an external random force. Under the condition that the distribution
of perturbation is sufficiently non-degenerate, a strong law of large numbers (SLLN) and a central limit theorem (CLT) for
solutions are established and the corresponding rates of convergence are estimated. It is also shown that the estimates obtained
are close to being optimal. The proofs are based on the property of exponential mixing for the problem in question and some
abstract SLLN and CLT for mixing-type Markov processes. 相似文献
99.
100.
Chang-Wan Kim 《Archiv der Mathematik》2007,88(4):378-384
We showed that any compact locally symmetric Finsler metric with positive flag curvature must be Riemannian.
Dedicated to Professor Karsten Grove on the occassion of his sixtieth birthday
Received: 8 May 2006 相似文献