631 research outputs found
Models simulation and interoperability using MDA and HLA
In the manufacturing context, there have been numerous efforts to use
modeling and simulation tools and techniques to improve manufacturing
efficiency over the last four decades. While an increasing number of
manufacturing system decisions are being made based on the use of models, their
use is still sporadic in many manufacturing environments. Our paper advocates
for an approach combining MDA (model driven architecture) and HLA (High Level
Architecture), the IEEE standard for modeling and simulation, in order to
overcome the deficiencies of current simulation methods at the level of
interoperability and reuse.Comment: 8 page
A new realization of quantum algebras in gauge theory and Ramification in the Langlands program
We realize the fundamental representations of quantum algebras via the
supersymmetric Higgs mechanism in gauge theories with 8 supercharges on an
-background. We test our proposal for quantum affine algebras, by
probing the Higgs phase of a 5d quiver gauge theory on a circle. We show that
our construction implies the existence of tame ramification in the
Aganagic-Frenkel-Okounkov formulation of the geometric Langlands program, a
correspondence which identifies -conformal blocks of the quantum affine
algebra with those of a Langlands dual deformed -algebra. The new
feature of ramified blocks is their definition in terms of Drinfeld polynomials
for a set of quantum affine weights. In enumerative geometry, the blocks are
vertex functions counting quasimaps to quiver varieties describing moduli
spaces of vortices. Physically, the vortices admit a description as a 3d quiver gauge theory on the Higgs branch of the 5d gauge theory, uniquely
determined from the Drinfeld polynomial data; the blocks are supersymmetric
indices for the vortex theory supported on a 3-manifold with distinguished BPS
boundary conditions. The top-down explanation of our results is found in the 6d
little string theory, where tame ramification is provided by certain
D-branes. When the string mass is taken to be large, we make contact with
various physical aspects of the point particle superconformal limit: the
Gukov-Witten description of ramification via monodromy defects in 4d Super
Yang-Mills (and their S-duality), the Nekrasov-Tsymbaliuk solution to the
Knizhnik-Zamolodchikov equations, and the classification of massive
deformations of tamely ramified Hitchin systems. In a companion paper, we will
show that our construction implies a solution to the local
Alday-Gaiotto-Tachikawa conjecture.Comment: 246 pages, 18 figures; v.2: added references, fixed typos and figure
Toward digital twins for sawmill production planning and control : benefits, opportunities and challenges
Sawmills are key elements of the forest product industry supply chain, and they play important economic, social, and environmental roles. Sawmill production planning and control are, however, challenging owing to severalfactors, including, but not limited to, the heterogeneity of the raw material. The emerging concept of digital twins introduced in the context of Industry 4.0 has generated high interest and has been studied in a variety of domains, including production planning and control. In this paper, we investigate the benefits digital twins would bring to the sawmill industry via a literature review on the wider subject of sawmill production planning and control. Opportunities facilitating their implementation, as well as ongoing challenges from both academic and industrial perspectives, are also studied
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