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[en] Natural resource revenues differ from other government revenues both in their time profile, and in their political and legal status: they are volatile and exhaustible, and belong to all citizens of the country in which they are located. This paper discusses the theory of natural resource revenues and examines expenditure practices in a range of resource-rich countries. It considers both the distributional impact and the efficiency of expenditure policies, focusing on the extent to which they succeed in providing all citizens with their share of the benefits due to natural resources. - Highlights: ► We examine the relationship between resource rents and government resource revenues. ► We discuss the intertemporal management of resource revenues in theory and in practice. ► We critically examine existing policies for distributing resource revenues to populations.
[en] The Lick observatory counts of galaxies are considered. The distribution of number of galaxies in elementary regions (ER) of 1 degx1 deg is investigated. Each field of 6 degx6 deg was treated separately At b>40 deg the probab+lity to observe of n galaxies in ER is an exponential decreasing function of n, if unequality n>< n> were fulfilled. The mean apparent multiplicity of a galaxy (2.8+-0.9) was derived. The galaxy number distribution was simple model for the number of various systems of galaxies. The supperclustering of galaxies was not introduced. Based on that model the approximate expression for galaxy number distribution was considered and was compared with observed distributions. The agreement between these distributions become better with reducing of the interstellar absorption of light
[en] We demonstrate two distinctive effects of strain-induced island-island interaction on island size and spatial distribution during coarsening of 2D islands. When coarsening proceeds via only mass transport between islands, the interaction broadens the island size distribution, leading to a power-law dependence of island size uniformity on island number density. When coarsening proceeds via island migration in addition to mass transport between islands, the interaction can effectively direct island motion through island edge diffusion, leading to self-organized formation of a regular array of islands with both uniform size and spacing
[en] We analyze the joint distributions and temporal correlations between the partial maximum m and the global maximum M achieved by a Brownian bridge on the subinterval and on the entire interval , respectively. We determine three probability distribution functions: the joint distribution of both maxima; the distribution P(m) of the partial maximum; and the distribution of the gap between the maxima, . We present exact results for the moments of these distributions and quantify the temporal correlations between m and M by calculating the Pearson correlation coefficient. (paper)
[en] The results are presented of a series of experiments investigating effects which may influence the data from ionisation-based dust impact detectors. After a brief review of dust detection techniques and methods of laboratory dust acceleration, experimental work is described in which the effects of dust impacts at oblique angles, secondary ionisation from side-wall ricochets and the contribution to ionisation from particle charge are studied. The experimental work was performed using the 2MV Van de Graaff accelerator facility at the University of Kent at Canterbury. To investigate the angular effect on ionisation signal, iron dust particles with velocities of 1-75 km s-1 were impacted onto a gold target at angles of 0 deg, 40 deg, 60 deg and 80 deg. No effect was observed for angles of 60 deg or less, but some variation was present in the 80 deg case. The effect of secondary ionisation from side-wall ricochets was investigated by impacting iron dust particles on to a gold target at 15 deg, 30 deg and 75 deg and measuring any ionisation signal on a nearby aluminium target. It was found that ionisation signals were frequently produced at the secondary target, and that these were very similar in appearance to signals from direct impacts. Two experiments were performed to study the influence of particle charge on impact ionisation. In the first, charged spheres with velocities of only a few m s-1 were dropped on to a replica of the Gorid dust detector, and any ionisation signal was measured. It was found that ionisation signals were frequently detected during these impacts. In the second experiment, iron dust particles were accelerated on to a gold target and had their charge reduced by passing through a thin film. It was found that the ionisation signal was slightly reduced in the charge-stripped case. The measured shifts in ionisation signal due to the three effects were applied to sample mass and velocity data collected by the Gorid dust detector. The oblique impact effect caused a downward shift of an order of magnitude in the mass distribution, and an upward shift of a factor of two in the velocity distribution. The side-wall impact effect caused a downward shift of around three orders of magnitude in the mass distribution, and an upward shift of a factor of five m the velocity distribution. The particle charge effects produced a downward shift of 30% in the mass distribution, and did not alter the velocity distribution. It is concluded that the data from ionisation-based dust detectors will be influenced by these effects, and that future analysis should bear them in mind. (author)
[en] This paper aims to explore the inherent connection between Heisenberg groups, quantum Fourier transform (QFT) and (quasi-probability) distribution functions. Distribution functions for continuous and finite quantum systems are examined from three perspectives and all of them lead to Weyl-Gabor-Heisenberg groups. The QFT appears as the intertwining operator of two equivalent representations arising out of an automorphism of the group. Distribution functions correspond to certain distinguished sets in the group algebra. The marginal properties of a particular class of distribution functions (Wigner distributions) arise from a class of automorphisms of the group algebra of the Heisenberg group. We then study the reconstruction of the Wigner function from the marginal distributions via inverse Radon transform giving explicit formulae. We consider some applications of our approach to quantum information processing and quantum process tomography.
[en] In this short communication we present a possible scheme to study the radial distribution function of the quantum slightly polydisperse Baxter sticky hard sphere liquid at finite temperature thorugh a semi-analytical method devised by Chandler and Wolynes. (paper: quantum statistical physics, condensed matter, integrable systems)
[en] Reactor core and fuel pin geometry of cylindrical pin arise heterogeneity of power generation along both axial and radial spaces. It influences the temperature and microstructures change distribution across the fuel and related properties. The present paper deal with sensitivity analyses of temperature and thermal property distribution by the axial and radial power distribution. A thermal model is developed for processing simulation using the given data. The analyses are performed using the model for power distribution effect on fuel properties and temperature distribution. The numerical result is resumed and presented. Qualitatively, the sensitivity is too important to be omitted in performance model. (author)