Thermoluminescence and optically stimulated luminescence of gamma-irradiated mineral zircon

Thermoluminescence (TL) manifested by gamma-irradiated mineral zircon has shown a strong TL peak at about 165 °C which is due to recombination of electrons and Dy3+ related shallow hole traps. After they have been removed by a short preheat we have observed two TL peaks at 300-320 °C and ≈420 °C, which are mainly due to recombination of electrons and Tb3+ related hole traps centres yielding its characteristic luminescence. The experimental results indicate that optically stimulated luminescence (OSL) is due to luminescent emission of Tb3+ ions and [SiO4]4– groups. The deep traps related to the 420 °C TL peak contribute to the Tb3+ related OSL. The deep traps related to the 300-320 °C TL peak contribute to OSL associated with the luminescent emission of [SiO4]4– groups.

Combining kernel estimators in the uniform deconvolution problem

We construct a density estimator and an estimator of the distribution function in the uniform deconvolution model. The estimators are based on inversion formulas and kernel estimators of the density of the observations and its derivative. Asymptotic normality and the asymptotic biases are derived

Asymptotic normality of the deconvolution kernel density estimator under the vanishing error variance

Let $X_1,...,X_n$ be i.i.d. observations, where $X_i=Y_i+\sigma_n Z_i$ and the $Y$'s and $Z$'s are independent. Assume that the $Y$'s are unobservable and that they have the density $f$ and also that the $Z$'s have a known density $k.$ Furthermore, let $\sigma_n$ depend on $n$ and let $\sigma_n\to 0$ as $n\to\infty.$ We consider the deconvolution problem, i.e. the problem of estimation of the density $f$ based on the sample $X_1,...,X_n.$ A popular estimator of $f$ in this setting is the deconvolution kernel density estimator. We derive its asymptotic normality under two different assumptions on the relation between the sequence $\sigma_n$ and the sequence of bandwidths $h_n.$ We also consider several simulation examples which illustrate different types of asymptotics corresponding to the derived theoretical results and which show that there exist situations where models with $\sigma_n\to 0$ have to be preferred to the models with fixed $\sigma.$Comment: 22 pages, 8 figure

A mixed integer quadratic programming formulation for the economic dispatch of generators with prohibited operating zones

In this paper, an optimisation-based approach is proposed using a mixed integer quadratic programming model for the economic dispatch of electrical power generators with prohibited zones of operation. The main advantage of the proposed approach is its capability to solve case studies from the literature to global optimality quickly and without any targeting of solution procedures. (c) 2006 Elsevier B.V. All rights reserved