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 $\Omega$-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 $q$-conformal blocks of the quantum affine algebra with those of a Langlands dual deformed ${\cal W}$-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 ${\cal N}=2$ 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 $(2,0)$ 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