Surface tension implementation for Gensmac 2D

In the present work we describe a method which allows the incorporation of surface tension into the GENSMAC2D code. This is achieved on two scales. First on the scale of a cell, the surface tension effects are incorporated into the free surface boundary conditions through the computation of the capillary pressure. The required curvature is estimated by fitting a least square circle to the free surface using the tracking particles in the cell and in its close neighbors. On a sub-cell scale, short wavelength perturbations are filtered out using a local 4-point stencil which is mass conservative. An efficient implementation is obtained through a dual representation of the cell data, using both a matrix representation, for ease at identifying neighbouring cells, and also a tree data structure, which permits the representation of specific groups of cells with additional information pertaining to that group. The resulting code is shown to be robust, and to produce accurate results when compared with exact solutions of selected fluid dynamic problems involving surface tension

Privatization and State Capacity in Postcommunist Society

Economists have used cross-national regression analysis to argue that postcommunist economic failure is the result of inadequate adherence liberal economic policies. Sociologists have relied on case study data to show that postcommunist economic failure is the outcome of too close adherence to liberal policy recommendations, which has led to an erosion of state effectiveness, and thus produced poor economic performance. The present paper advances a version of this statist theory based on a quantitative analysis of mass privatization programs in the postcommunist world. We argue that rapid large-scale privatization creates severe supply and demand shocks for enterprises, thereby inducing firm failure. The resulting erosion of tax revenues leads to a fiscal crisis for the state, and severely weakens its capacity and bureaucratic character. This, in turn, reacts back on the enterprise sector, as the state can no longer support the institutions necessary for the effective functioning of a modern economy, thus resulting in deindustrialization. Using cross-national regression techniques we find that the implementation of mass privatization programs negatively impacts measures of economic growth, state capacity and the security of property rights.http://deepblue.lib.umich.edu/bitstream/2027.42/40192/3/wp806.pd

Effects of Compression and Collective Expansion on Particle Emission from Central Heavy-Ion Reactions

Conditions under which compression occurs and collective expansion develops in energetic reactions of heavy nuclei, are analyzed, together with their effects on emitted light baryons and pions. Within transport simulations, it is shown that shock fronts perpendicular to beam axis form in head-on reactions. The fronts separate hot compressed matter from normal. As impact parameter increases, the angle of inclination of the fronts relative to beam axis decreases, and in-between the fronts a weak tangential discontinuity develops. Hot matter exposed to the vacuum in directions perpendicular to shock motion (and parallel to fronts), starts to expand sideways, early within reactions. Expansion in the direction of shock motion follows after the shocks propagate through nuclei, but due to the delay does not acquire same strength. Expansion affects angular distributions, mean-energy components, shapes of spectra and mean energies of different particles emitted into any one direction, and further particle yields. Both the expansion and a collective motion associated with the weak discontinuity, affect the magnitude of sideward flow within reaction plane. Differences in mean particle energy components in and out of the reaction plane in semicentral collisions, depend sensitively on the relative magnitude of shock speed in normal matter and speed of sound in hot matter.Comment: 71 pages, 33 figures (available on request), report MSUCL-94

The influence of industrial policy and national systems of innovation on emerging economy suppliers’ learning capability

This paper links the industrial policy and national systems of innovation literature to the investigation of learning capabilities of suppliers in the context of the automotive parts industry of Pakistan. Drawing data from 50 Pakistani autoparts suppliers, the findings suggest that industrial policy has been helpful in creating a local parts supply base and facilitating the entry of Japanese assemblers in the market. However, the implementation of the policy has been weak, and it is an arduous journey for the local suppliers to develop ambidextrous (exploratory and exploitative) learning capabilities. The findings also indicate that where local training and support from R&D institutions are weak, networking alone with foreign multinationals is not sufficient on its own to develop exploratory learning capabilities of local suppliers. This paper shows the importance of creating national–provincial institutions offering learning and skills development aimed towards innovation

Natural convection in a square cavity with uniformly heated and/or insulated walls using marker-and-cell method

In this study, a numerical investigation has been performed using the computational Harlow-Welch MAC (Marker and Cell) finite difference method to analyse the unsteady state two-dimensional natural convection in lid-driven square cavity with left wall maintained at constant heat flux and remaining walls kept thermally insulated. The significant parameters in the present study are Reynolds number (Re), thermal Grashof number (Gr) and Prandtl number (Pr) and Peclét number (Pe =PrRe). The structure of thermal convection patterns is analysed via streamline, vorticity, pressure and temperature contour plots. The influence of the thermophysical parameters on these distributions is described in detail. Validation of solutions with earlier studies is included. Mesh independence is also conducted. It is observed that an increase in Prandtl number intensifies the primary circulation whereas it reduces the heat transfer rate. Increasing thermal Grashof number also decreases heat transfer rates. Furthermore the isotherms are significantly compressed towards the left (constant flux) wall with a variation in Grashof number while Peclét number is fixed. The study is relevant to solar collector heat transfer simulations and also crystal growth technologies