The National Wealth of Selected Countries - A Descriptive Essay

What determines the wealth of nations? If anyone knew the answer to that question, no-one would have heard of Adam Smith as an economist, and for that matter all economists. Economics is really the study of wealth creation under scarcity. The reason economists and others have a hard time pinning down the causes of wealth is that wealth is costly to measure, and many factors and forces are potential determinants. This paper describes, in a simple way, wealth accounting by extending the data assembled by a recent World Bank study. The extension will benefit those seeking to run time-series, cross-section, and/or pooled data regressions to assess how wealth is determined. But even from this simple data mining exercise alone the results indicate significant increases in the wealth of the 92 countries in this sample. From the theoretical standpoint the World Bank’s expanded measure under-estimates the wealth of developing countries. Yet, even if the income (GDP) component of their wealth has fallen, total national wealth has increased. The policy implications of this essay are tentative until empirical analysis is carried; even so, the results seem to suggest that GDP is a necessary but not a sufficient requirement for wealth.national wealth; Alfred Marshall on wealth, estimating wealth, World Bank’s national wealth estimating

Exchange coupling between magnetic layers across non-magnetic superlattices

The oscillation periods of the interlayer exchange coupling are investigated when two magnetic layers are separated by a metallic superlattice of two distinct non-magnetic materials. In spite of the conventional behaviour of the coupling as a function of the spacer thickness, new periods arise when the coupling is looked upon as a function of the number of cells of the superlattice. The new periodicity results from the deformation of the corresponding Fermi surface, which is explicitly related to a few controllable parameters, allowing the oscillation periods to be tuned.Comment: 13 pages; 5 figures; To appear in J. Phys.: Cond. Matte

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A discrete particle simulation study on the influence of restitution coefficient on spout fluidized bed dynamics

In this paper the influence of the normal restitution coefficient on the bed dynamics\ud during different flow regimes was studied using the discrete element model. The three flow\ud regimes comprise the intermediate/spout-fluidization, spouting-with-aeration regime and the jetin-\ud fluidized-bed. It is shown that with increase of the restitution coefficient the average bed\ud height decreases for all flow regime cases. To study the influence of the granule impact velocity\ud and the liquid film on the wall surface the free-fall experiments in the velocity range of 0.5-\ud 4.5 m/s were performed with spherical γ-Al2O3 granules. During the free-fall tests, the impact\ud angle from 0° to 80° and the viscosity of thin liquid film in the range of 1-300 mPa·s were\ud varied

Numerical evaluation of two-loop integrals with pySecDec

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