Image-based Restoration of the Concrete Void System Using 2D-to-3D Unfolding Technique

Hardened air void analysis provides essential information of concrete freeze-thaw durability based on the size and spacing of air voids in the material. As the physical freeze-thaw experiment is time-consuming and costly, the characteristics of concrete air voids are often deemed as a proxy of the freeze-thaw performance. This analysis is typically done by measuring the 2D air void intersections on polished samples, but the current interpretation of the 2D void characters does not accurately represent the actual void structure in 3D. To solve this problem, a 2D-to-3D unfolding technique has been proposed in the field of stereology. However, the unfolding analysis is known to be sensitive to several factors, such as void population and size along with a binning scheme, where improper unfolding can considerably bias the prediction of the actual concrete void system. This study investigates the optimal strategy of conducting the unfolding analysis for concrete. The investigation is carried out on both idealized void systems to interrogate the influence of the critical factors individually, and real concrete samples with varying levels of air entrainment to assess the concrete-specific impacts. The concrete void system is studied based on a stereological model emulating the intersected 3D air voids on the surface of polished concrete. The results highlight that, for unfolding concrete voids, logarithmic binning scheme is far more accurate to linear binning. The low unfolding error of the concrete samples indicates that the proposed methodology enables an accurate restoration of 3D void size distribution.

The cosmopolitan subject and the question of cultural identity: The case of Crime and Punishment

Though contemporary discourse on cosmopolitanism has celebrated a cosmopolitan subject’s “rootedness” in two worlds – i.e. the polis and the cosmos – this emphasis has evaded analysis of the historical and damning term “rootless cosmopolitan.” Under the totalitarianisms of Nazism and late Stalinism, a “rootless cosmopolitan” was a life-threatening epithet aimed at those people, namely “the Jews,” criminalized for supposedly lacking national allegiance and affiliating with foreign cultures. This paper argues that an ethical problem arises when cosmopolitanism is understood in cultural terms. To illuminate this problem in the particular, this paper interprets Dostoevsky’s Crime and Punishment, specifically the novel’s nationalistic themes and its cosmopolitan villain, Peter Petrovich Luzhin. In the unfolding analysis that draws from scholarship in cultural criminology, it is revealed that the Russian writer’s designated masterful genius helped fuel one of the greatest crimes in history (the Holocaust) perpetrated against a people accused of cosmopolitanism. It is argued that interpreting the criminalization of Luzhin provides an allegorical occasion to gain conceptual clarity on present articulations of cosmopolitanism as a cultural construct. Attending to Dostoevsky’s anti-cosmopolitanism, and those whom he has in/directly influenced on this subject, provides a rationale for critiquing cultural cosmopolitanism – a construct that is conceptually and materially dangerous.