By the Bogoliubov prescription and the method of Gross and Pitaevskii in quantum field theory, the relativistic almost ideal Bose-Eintein gas at zero temperature is discussed. Special attention is given to the study of a vortex in the gas. The field description and fluid approximation are compared. PACS: 11.10.-z, 05.30.Jp, 47.75.+f, 47.37.+q

This paper presents a version of the proportionally calibrated almost ideal demand system (PCAIDS) model, useful for merger simulations, which can be econometrically estimated using price data for two firms in a market. The model is then applied to a database of the Argentine gasoline market, and its results are compared to the ones obtained with other alternative specifications. JEL Classifica...

Consider a system of linear algebraic equations with a nonsingular n by n matrix A. When solving this system with GMRES, the relative residual norm at the step k is bounded from above by the so called ideal GMRES approximation. This bound is sharp (it is attainable by the relative GMRES residual norm) in case of a normal matrix A, but it need not characterize the worstcase GMRES behavior if A i...

this paper estimates demand functions for wireless and wireline phone, using almost ideal demand system (aids) and attempts to test the hypothesis of substitutability between wireless and wireline in iran. the results indicate that the number of mobile subscribers has been growing more than the number of wireline subscribers over studied period. this maybe because of lower price of mobile acces...

We present a stochastic version of the single-level, multi-product dynamic lotsizing problem subject to a capacity constraint. A production schedule has to be determined for random demand so that expected costs are minimized and a constraint based on a new backlog-oriented δ-service-level measure is met. This leads to a non-linear model that is approximated by two different linear models. In th...