The fragmentation of alumina and glass plates due to lateral impact is studied. A few hundred plates have been fragmented at different impact velocities and the produced fragments are analyzed. The method employed in this work allows one to investigate some geometrical properties of the fragments, besides the traditional size distribution usually studied in former experiments. We found that, although both materials exhibit qualitative similar fragment size distribution function, their geometrical properties appear to be quite different. A schematic model for two-dimensional fragmentation is also presented and its predictions are compared to our experimental results. The comparison suggests that the analysis of the fragments' geometrical properties constitutes a more stringent test of the theoretical models' assumptions than the size distribution.

Stochastic models for the development of cracks in 1 and 2 dimensional objects are presented. In one dimension, we focus on particular scenarios for interacting and non-interacting fragments during the breakup process. For two dimensional objects, we consider only non-interacting fragments, but analyze isotropic and anisotropic development of fissures. Analytical results are given for many observables. Power-law size distributions are predicted for some of the fragmentation pictures considered.

The breakup of alkaline glass and alumina plates due to planar impacts on one of their lateral sides is studied. Particular attention is given to investigating the spatial location of the cracks within the plates. Analysis based on a phenomenological model suggests that bifurcations along the cracks' paths are more likely to take place closer to the impact region than far away from it, i.e., the bifurcation probability seems to lower as the perpendicular distance from the impacted lateral increases. It is also found that many observables are not sensitive to the plate material used in this work, as long as the fragment multiplicities corresponding to the fragmentation of the plates are similar. This gives support to the universal properties of the fragmentation process reported in previous experiments. However, even under the just mentioned circumstances, some spatial observables are capable of distinguishing the material of which the plates are made, which therefore suggests that this universality should be carefully investigated.

Automação na drenagem urbana é um tema que soa como futurista, mas mostraremos neste revisão bibliográfica que já é um assunto abordado há décadas, com início na Europa, Estados Unidos e Ásia. Serão apresentados sistemas e métodos inovadores que atuam sobre soluções clássicas da engenharia melhorando o desempenho da drenagem urbana e reduzindo impactos das crescentes inundações urbanas. Mostraremos tanques de captação de águas de chuvas, reservatórios de controle de cheias, bueiros inteligentes, robôs autônomos para inspeção e desobstrução de tubulações e outros exemplos de soluções diretas para drenagem urbana e controle de inundações. Novos modelos de análise probabilística processam de imagens via satélite e dados de sensoriamento local refinam a previsão meteorológica e as estimativas de impactos de eventos climáticos extremos, levando à melhoria do planejamento contra desastres, de ações de pronta resposta e desenvolvimento de soluções integradas de longo prazo no planejamento urbano.