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This paper aims to assess the strengths and weaknesses of four thermodynamic models used in aircraft icing simulations to orient the development or the choice of an improved thermodynamic model.

Four models are compared to assess their capabilities: Messinger, iterative Messinger, extended Messinger and shallow water icing models. They have been implemented in the aero-icing framework, NSCODE-ICE, under development at Polytechnique Montreal since 2012. Comparison is performed over typical rime and glaze ice cases. Furthermore, a manufactured geometry with multiple recirculation zones is proposed as a benchmark test to assess the efficiency in runback water modeling and geometry evolution.

The comparison shows that one of the main differences is the runback water modeling. Runback modeling based on the location of the stagnation point fails to capture the water film behavior in the presence of recirculation zones on airfoils. However, runback modeling based on air shear stress is more suitable in this situation and can also handle water accumulation while the other models cannot. Also, accounting for the conduction through the ice layer is found to have a great impact on the final ice shape as it increases the overall freezing fraction.

This paper helps visualize the effect of different thermodynamic models implemented in the same aero-icing framework. Also, the use of a complex manufactured geometry highlights weaknesses not normally noticeable with classic ice accretion simulations. To help with the visualization, the ice shape is presented with the water layer, which is not shown on typical icing results.

Roger Koppl (2009, p. 1) argues that “Austrian economics is a school of thought within the broader complexity movement in economics.” Is he correct? Although there are many who have argued for some overlapping between the two, I shall argue that this is probably an overly strong statement. The main reason is that there are substantial elements and strands within Austrian economics that do not fit in with any of the multiple varieties of complexity theory, even though there are some that clearly do.

This paper aims to examine the experience of women entrepreneurs and the challenges and issues they face in reconciling the work activities of the family sphere with those of the entrepreneurial sphere.

This study is based on a materialist feminist perspective and a theory of living work that take into account the visible and invisible dimensions of the real work performed by women entrepreneurs. The methodology is based on a qualitative research design involving individual and group interviews conducted with 70 women entrepreneurs.

The results show the various individual and collective strategies deployed by women entrepreneurs to reconcile the work activities of the family and entrepreneurial spheres.

One of the major findings emerging from the results of this study relates to the re-appropriation of the world of work and organization of work by women entrepreneurs and its emancipatory potential for the division of labour. Through the authority and autonomy they possessed as business owners, and with their employees’ cooperation, they integrated and internalized tasks related to the work activities of the family sphere into the organization of work itself. Thus, not only new forms of work organization and cooperation at work but also new ways of conceiving of entrepreneurship as serving women’s life choices and emancipation could be seen to be emerging.