Do Employment Quotas Explain the Occupational Choices of Disadvantaged Minorities in India?

This article investigates the effects of a large-scale public sector employment quota policy for disadvantaged minorities (Scheduled Castes and Scheduled Tribes) in India on their occupational choices, as defined by skill level, during the 1980s and 1990s. We find that, first, the employment quota policy significantly affects the occupational structure of both disadvantaged minority populations. In response to the employment quotas, individuals belonging to the Scheduled Caste group are more likely to choose high-skill occupations and less likely to choose low- and middle-skill occupations, while individuals belonging to the Scheduled Tribe group are less likely to choose high-skill occupations and more likely to choose low- and middle-skill occupations. Second, the impact of the employment quotas is significantly related with an individual's years of schooling. Overall, the results indicate that the employment quota policy changes the occupational choices of individuals within the targeted populations and contributes to their improved socio-economic standing.skill, affirmative action, employment quota, occupational choice, caste, India

Thermal effects on nuclear symmetry energy with a momentum-dependent effective interaction

The knowledge of the nuclear symmetry energy of hot neutron-rich matter is important for understanding the dynamical evolution of massive stars and the supernova explosion mechanisms. In particular, the electron capture rate on nuclei and/or free protons in presupernova explosions is especially sensitive to the symmetry energy at finite temperature. In view of the above, in the present work we calculate the symmetry energy as a function of the temperature for various values of the baryon density, by applying a momentum-dependent effective interaction. In addition to a previous work, the thermal effects are studied separately both in the kinetic part and the interaction part of the symmetry energy. We focus also on the calculations of the mean field potential, employed extensively in heavy ion reaction research, both for nuclear and pure neutron matter. The proton fraction and the electron chemical potential, which are crucial quantities for representing the thermal evolution of supernova and neutron stars, are calculated for various values of the temperature. Finally, we construct a temperature dependent equation of state of $\beta$-stable nuclear matter, the basic ingredient for the evaluation of the neutron star properties.Comment: 18 pages, 10 figures, 1 table, accepted for publication in Physical Review

Propulsion simulator for magnetically-suspended wind tunnel models

The objective of phase two of a current investigation sponsored by NASA Langley Research Center is to demonstrate the measurement of aerodynamic forces/moments, including the effects of exhaust gases, in magnetic suspension and balance system (MSBS) wind tunnels. Two propulsion simulator models are being developed: a small-scale and a large-scale unit, both employing compressed, liquified carbon dioxide as propellant. The small-scale unit was designed, fabricated, and statically-tested at Physical Sciences Inc. (PSI). The large-scale simulator is currently in the preliminary design stage. The small-scale simulator design/development is presented, and the data from its static firing on a thrust stand are discussed. The analysis of this data provides important information for the design of the large-scale unit. A description of the preliminary design of the device is also presented

Rouse Chains with Excluded Volume Interactions: Linear Viscoelasticity

Linear viscoelastic properties for a dilute polymer solution are predicted by modeling the solution as a suspension of non-interacting bead-spring chains. The present model, unlike the Rouse model, can describe the solution's rheological behavior even when the solvent quality is good, since excluded volume effects are explicitly taken into account through a narrow Gaussian repulsive potential between pairs of beads in a bead-spring chain. The use of the narrow Gaussian potential, which tends to the more commonly used delta-function repulsive potential in the limit of a width parameter "d" going to zero, enables the performance of Brownian dynamics simulations. The simulations results, which describe the exact behavior of the model, indicate that for chains of arbitrary but finite length, a delta-function potential leads to equilibrium and zero shear rate properties which are identical to the predictions of the Rouse model. On the other hand, a non-zero value of "d" gives rise to a prediction of swelling at equilibrium, and an increase in zero shear rate properties relative to their Rouse model values. The use of a delta-function potential appears to be justified in the limit of infinite chain length. The exact simulation results are compared with those obtained with an approximate solution which is based on the assumption that the non-equilibrium configurational distribution function is Gaussian. The Gaussian approximation is shown to be exact to first order in the strength of excluded volume interaction, and is found to be accurate above a threshold value of "d", for given values of chain length and strength of excluded volume interaction.Comment: Revised version. Long chain limit analysis has been deleted. An improved and corrected examination of the long chain limit will appear as a separate posting. 32 pages, 9 postscript figures, LaTe

Do means-tested school lunch subsidies change children's weekly consumption patterns?

This article examines whether the means-tested component of the National School Lunch Program changes beneficiaries' dietary patterns by taking advantage of variation across public school districts in the financing of and demand for lunch and nutrition programs. Using data on fifth grade public elementary school children in the Early Childhood Longitudinal Study-Kindergarten (2003-2004), we find significant increases in weekly rates of consumption amongst fully and partially subsidized children. Our estimates also suggest that the increase was for items known to be a rich source of vitamins and minerals that are essential for children's health and development. The effects are larger for fully subsidized children relative to partially subsidized children, which suggests the nominal price of school lunch is a binding constraint for certain children on the margin of eligibility for the subsidies. To the extent that children from low-income households experience undernourishment with greater frequency, policy discussion focusing exclusively on the link between obesity and program participation is overlooking positive effects on those who are directly subsidized

Do employment quotas explain the occupational choices of disadvantaged minorities in India?

This article investigates the effects of a large-scale public sector employment quota policy for disadvantaged minorities (Scheduled Castes and Scheduled Tribes) in India on their occupational choices, as defined by skill level, during the 1980s and 1990s. We find that, first, the employment quota policy significantly affects the occupational structure of both disadvantaged minority populations. In response to the employment quotas, individuals belonging to the Scheduled Caste group are more likely to choose high-skill occupations and less likely to choose low- and middle-skill occupations, while individuals belonging to the Scheduled Tribe group are less likely to choose high-skill occupations and more likely to choose low- and middle-skill occupations. Second, the impact of the employment quotas is significantly related with an individual's years of schooling. Overall, the results indicate that the employment quota policy changes the occupational choices of individuals within the targeted populations and contributes to their improved socio-economic standing

Shortest Paths, Network Design and Associated Polyhedra

We study a specialized version of network design problems that arise in telecommunication, transportation and other industries. The problem, a generalization of the shortest path problem, is defined on an undirected network consisting of a set of arcs on which we can install (load), at a cost, a choice of up to three types of capacitated facilities. Our objective is to determine the configuration of facilities to load on each arc that will satisfy the demand of a single commodity at the lowest possible cost. Our results (i) demonstrate that the single-facility loading problem and certain "common breakeven point" versions of the two-facility and three-facility loading problems are polynomially solvable as a shortest path problem; (ii) show that versions of the twofacility loading problem are strongly NP-hard, but that a shortest path solution provides an asymptotically "good" heuristic; and (iii) characterize the optimal solution (that is, specify a linear programming formulation with integer solutions) of the common breakeven point versions of the two-facility and three-facility loading problems. In this development, we introduce two new families of facets, give geometric interpretations of our results, and demonstrate the usefulness of partitioning the space of the problem parameters to establish polyhedral integrality properties. Generalizations of our results apply to (i) multicommodity applications and (ii) situations with more than three facilities