On Dual Formulations of Massive Tensor Fields

In this paper we investigate dual formulations for massive tensor fields. Usual procedure for construction of such dual formulations based on the use of first order parent Lagrangians in many cases turns out to be ambiguous. We propose to solve such ambiguity by using gauge invariant description of massive fields which works both in Minkowski space as well as (Anti) de Sitter spaces. We illustrate our method by two concrete examples: spin-2 "tetrad" field h_{\mu a}, the dual field being "Lorentz connection" \omega_{\mu,ab} and "Riemann" tensor R_{\mu\nu,ab} with the dual \Sigma_{\mu\nu,abc}.Comment: 9 pages, plain LaTe

Travelling-wave similarity solutions for an unsteady shear-stress-driven dry patch in a flowing film

We investigate unsteady flow of a thin film of Newtonian fluid around a symmetric slender dry patch moving with constant velocity on an inclined planar substrate, the flow being driven by a prescribed constant shear stress at the free surface of the film (which would be of uniform thickness in the absence of the dry patch). We obtain a novel unsteady travelling-wave similarity solution which predicts that the dry patch has a parabolic shape and that the film thickness increases monotonically away from the dry patch

Stability of the Magnetic Monopole Condensate in three- and four-colour QCD

It is argued that the ground state of three- and four-colour QCD contains a monopole condensate, necessary for the dual Meissner effect to be the mechanism of confinement, and support its stability on the grounds that it gives the off-diagonal gluons an effective mass sufficient to remove the unstable ground state mode.Comment: jhep.cls, typos corrected, references added, some content delete

A multi-country study of the adoption of ERP systems

Studies on the adoption of innovations by companies generally includemicro-level and meso-level variables in order to explain a company'sreceptiveness to innovations. This study adds to the literature byinvestigating the role of macro-level variables (i.e. nationalculture) to explain differences in innovation penetration levels andadoption decisions by companies across national cultures. Alarge-scale empirical study was carried out in 10 European countriesconcerning the adoption of Enterprise Resource Planning (ERP) softwareby mid size companies. Results indicate variables describing nationalcultural to have a strong, significant influence on the innovationpenetration and adoption. In addition, we find adoption modelsincluding micro-, meso- and macro-level variables to performsignificantly better in explaining innovation adoption acrosscountries than adoption models that only include micro- and meso-levelvariables.innovation;cross-cultural;organizational behavior;ERP

Intra-Firm Adoption Decisions

The subject of this paper is intra-firm adoption decisions, a relatively unexplored research area in the marketing literature. In particular, we investigate which factors influence the intra-firm adoption decisions regarding the common European currency of the treasury, purchasing and sales departments of European companies. Two sets of independent variables were hypothesized to influence the intra-firm adoption decisions, i.e. (1) variables known from the inter-firm diffusion literature, (2) variables specifically relevant for intra-firm analyses of innovation acceptance. The hypotheses are tested using data from treasury, purchasing and sales managers (441 respondents in total) from companies located in five different European countries. The results of logistic regression show that the proposed intra-firm variables are indeed important explanatory variables that should be included in intra-firm analyses. Moreover, for the inter-firm variables we found differences in the effects between departments, which demonstrates the very need for an intra-firm analysis.innovation;European Monetary Union;business marketing;intra-firm adoption;European marketing

Large Eddy Simulations of gaseous flames in gas turbine combustion chambers

Recent developments in numerical schemes, turbulent combustion models and the regular increase of computing power allow Large Eddy Simulation (LES) to be applied to real industrial burners. In this paper, two types of LES in complex geometry combustors and of specific interest for aeronautical gas turbine burners are reviewed: (1) laboratory-scale combustors, without compressor or turbine, in which advanced measurements are possible and (2) combustion chambers of existing engines operated in realistic operating conditions. Laboratory-scale burners are designed to assess modeling and funda- mental flow aspects in controlled configurations. They are necessary to gauge LES strategies and identify potential limitations. In specific circumstances, they even offer near model-free or DNS-like LES computations. LES in real engines illustrate the potential of the approach in the context of industrial burners but are more difficult to validate due to the limited set of available measurements. Usual approaches for turbulence and combustion sub-grid models including chemistry modeling are first recalled. Limiting cases and range of validity of the models are specifically recalled before a discussion on the numerical breakthrough which have allowed LES to be applied to these complex cases. Specific issues linked to real gas turbine chambers are discussed: multi-perforation, complex acoustic impedances at inlet and outlet, annular chambers.. Examples are provided for mean flow predictions (velocity, temperature and species) as well as unsteady mechanisms (quenching, ignition, combustion instabil- ities). Finally, potential perspectives are proposed to further improve the use of LES for real gas turbine combustor designs

Limit Theorems for Proportions of Balls in a Generalized Urn Scheme

In this paper the authors continue to study the process of growth modeled by urn schemes containing balls of different colors. The rate of convergence for proportions of balls to the limit state is investigated. It is shown that Gaussian as well as non-Gaussian Markov random processes may describe the asymptotic behavior

Metallaborane reaction chemistry. A facile and reversible dioxygen capture by a B-frame-supported bimetallic: structure of [(PMe2Ph)(4)(O-2)Pt2B10H10]

[(PMe2Ph)(4)Pt2B10H10] 1 reversibly takes up atmospheric dioxygen to give the fluxional dioxygen-dimetallaborane complex [(PMe2Ph)(4)(O-2)Pt2B10H10] 2, which has Pt-Pt 2.7143(3), Pt-O 2.141(4) and 2.151(4) and O-O 1.434(6) Angstrom