Macroscopic limit of a bipartite Curie-Weiss model: a dynamical approach

We analyze the Glauber dynamics for a bi-populated Curie-Weiss model. We obtain the limiting behavior of the empirical averages in the limit of infinitely many particles. We then characterize the phase space of the model in absence of magnetic field and we show that several phase transitions in the inter-groups interaction strength occur.Comment: 18 pages, 3 figure

The Definition and Measurement of the Topological Entropy per Unit Volume in Parabolic PDE's

We define the topological entropy per unit volume in parabolic PDE's such as the complex Ginzburg-Landau equation, and show that it exists, and is bounded by the upper Hausdorff dimension times the maximal expansion rate. We then give a constructive implementation of a bound on the inertial range of such equations. Using this bound, we are able to propose a finite sampling algorithm which allows (in principle) to measure this entropy from experimental data.Comment: 26 pages, 1 small figur

Botanical Fabrication: A research project at the intersection of design, botany and horticulture

‘Botanical Fabrication’ is an on-going research initiative which investigates how an understanding of botany and horticultural techniques can challenge the design process and lead to alternative sustainable manufacturing or ‘eco-facturing’ tools. This paper presents different phases of the project, from an initial research workshop (2012), to an exhibition-based experiment (Botanical Factory, 2013) and includes current work in progress (Solar Gourd, 2015) so as to articulate a critical analysis of the work to date. In a context where we urgently need to devise new principles to live, manufacture and consume within the ecological capacity of our finite planet, the paper argues for the development of a new framework for slow manufacturing with plant systems. From Darwin’s research into plant movements to our current understanding of plant physics and biomechanics, designers can begin to integrate botanical and horticultural knowledge to play with the environment of plant growth and envision production chains of a new type

A simple formula for the series of constellations and quasi-constellations with boundaries

We obtain a very simple formula for the generating function of bipartite (resp. quasi-bipartite) planar maps with boundaries (holes) of prescribed lengths, which generalizes certain expressions obtained by Eynard in a book to appear. The formula is derived from a bijection due to Bouttier, Di Francesco and Guitter combined with a process (reminiscent of a construction of Pitman) of aggregating connected components of a forest into a single tree. The formula naturally extends to $p$-constellations and quasi-$p$-constellations with boundaries (the case $p=2$ corresponding to bipartite maps).Comment: 23 pages, full paper version of v1, with results extended to constellations and quasi constellation

Thermal conductivity of hemp concretes: Variation with formulation, density and water content

This study investigates the effect of formulation, density and water content on the thermal conductivity of hemp concretes. The investigations are based on experimental measurements and on self-consistent scheme modelling. The thermal conductivity of studied materials ranges from 90 to 160 mW/(m.K) at (23 degrees C; 50%HR). The impact of density on thermal conductivity is much more important than the impact of moisture content. It is shown that the thermal conductivity increases by about 54 % when the density increases by 2/3 while it increases by less than 15 % to 20 % from dry state to 90%RH