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191.
General limit theorems are established for l~p-valued Gaussian random fields indexed by a multidimensional parameter,which contain both almost sure moduli of continuity and limits of large increments for the l~p-valued Gaussian random fields under(?)explicit conditions. 相似文献
192.
The classical Voigt functions occur frequently in a wide variety of problems in astrophysical spectroscopy, emission, absorption
and transfer of radiation in heated atmosphere, and plasma dispersion, and indeed also in the theory of neutron reactions.
Here, in the present paper, by applying several known upper bounds for the first-kind Bessel function J
ν
(x) given recently by (for example) Landau, Olenko and Krasikov, sharp bounding inequalities are obtained for the unified multivariable
Voigt function V
μ,ν
(x; y) in terms of the confluent Fox-Wright function 1ψ0 and its incomplete variant 1ψ0. Connections of the unified multivariable Voigt function V
μ,ν
(x; y) with other unifications and generalizations of the classical Voigt function are also briefly pointed out. 相似文献
193.
Marta Gimnez-Pedrs Ali Aghmiz Carmen Claver Anna M. Masdeu-Bult Denis Sinou 《Journal of molecular catalysis. A, Chemical》2003,200(1-2):157-163
High linear alkenes (1-octene and 1-decene) have been hydroformylated using water-soluble rhodium complexes associated with sulfonated diphosphines in the presence of ionic surfactants or methanol. In all cases, the hydroformylation activities were higher than in experiments without additives. The selectivity in aldehydes was higher when we used cetyltrimethylammonium hydrogensulfate (CTAHSO4) as the surfactant or methanol as the co-solvent. 相似文献
194.
E. Hernández L. Rodríguez-Marín 《Journal of Optimization Theory and Applications》2007,134(1):119-134
In this paper, we study optimization problems where the objective function and the binding constraints are set-valued maps
and the solutions are defined by means of set-relations among all the images sets (Kuroiwa, D. in Takahashi, W., Tanaka, T.
(eds.) Nonlinear analysis and convex analysis, pp. 221–228, 1999). We introduce a new dual problem, establish some duality theorems and obtain a Lagrangian multiplier rule of nonlinear type
under convexity assumptions. A necessary condition and a sufficient condition for the existence of saddle points are given.
The authors thank the two referees for valuable comments and suggestions on early versions of the paper. The research of the
first author was partially supported by Ministerio de Educación y Ciencia (Spain) Project MTM2006-02629 and by Junta de Castilla
y León (Spain) Project VA027B06. 相似文献
195.
J. M. Criado L. A. Pérez-Maqueda M. J. Diánez P. E. Sánchez-Jiménez 《Journal of Thermal Analysis and Calorimetry》2007,87(1):297-300
The SCTA method implies to control the temperature in such a way that
the reaction rate changes with the time according to a function previously
defined by the user. Constant Rate Thermal Analysis (CRTA) is one of the most
commonly used SCTA methods and implies achieving a temperature profile at
which the reaction rate remains constant all over the process at a value previously
selected by the user. This method permits to minimize the influence of heat
and mass transfer phenomena on the forward reaction. The scope of this work
is to develop a universal CRTA temperature controller that could be adapted
to any thermoanalytical device. The thermoanalytical signal is programmed
to follow a preset linear trend by means of a conventional controller that
at the time controls a second conventional temperature programmer that forces
the temperature to change for achieving the trend programmed for the thermoanalytical
signal. Examples of the performance of this control system with a Thermobalance
and a Thermomechanical Analyser (TMA) are given. 相似文献
196.
197.
198.
Jesús de la Cal Javier Cárcamo 《Journal of Mathematical Analysis and Applications》2007,334(2):1106-1115
As a consequence of Jensen's inequality, centered operators of probabilistic type (also called Bernstein-type operators) approximate convex functions from above. Starting from this fact, we consider several pairs of classical operators and determine, in each case, which one is better to approximate convex functions. In almost all the discussed examples, the conclusion follows from a simple argument concerning composition of operators. However, when comparing Szász-Mirakyan operators with Bernstein operators over the positive semi-axis, the result is derived from the convex ordering of the involved probability distributions. Analogous results for non-centered operators are also considered. 相似文献
199.
Generators of some Ramanujan formulas 总被引:2,自引:0,他引:2
Jesús Guillera 《The Ramanujan Journal》2006,11(1):41-48
In this paper we prove some Ramanujan type formulas for 1/π but without using the theory of modular forms. Instead we use
the WZ—method created by H. Wilf and D. Zeilberger and find some hypergeometric functions in two variables which are second
components of WZ—pairs than can be certified using Zeilberger's EKHAD package. These certificates have an additional property
which allows us to get generalized Ramanujan's type series which are routinely proven by computer. We call these second hypergeometric
components of the WZ—pairs generators. Finding generators seems a hard task but using a kind of experimental research (explained
below), we have succeeded in finding some of them. Unfortunately we have not found yet generators for the most impressive
Ramanujan's formulas. We also prove some interesting binomial sums for the constant 1/π2. Finally we rewrite many of the obtained series using pochhammer symbols and study the rate of convergence.
2000 Mathematics Subject Classification Primary—33C20 相似文献
200.
Simone Alfarano Iván Barreda-Tarrazona Eva Camacho-Cuena 《Central European Journal of Operations Research》2006,14(4):417-433
In this paper, we analyze the behavior of a group of heterogeneously informed investors in an laboratory asset market. Our experimental setting is inspired by Huber et al. (On the benefit of information in markets with heterogeneously informed traders: an experimental study, 2004). However, instead of their system of cumulative and exogenously given information structure, we introduce an information market where the traders can buy an imperfect prediction of the future value of the dividend with a maximum anticipation of four periods. The accuracy of the prediction decreases with the chosen time horizon, whereas its price remains constant. Our results confirm a non-strictly monotonic increasing value of the information. 相似文献