Análise Comparativa dos Acidentes de Trabalho no Brasil a partir de Dados Abertos

O presente artigo tem como objetivo analisar bases de dados abertas sobre  acidentes de trabalhado disponíveis pelo governo brasileiro.  Desta forma, este trabalho apresenta um demonstrativo dos principais índices  de acidentes de trabalho do país. Como resultado procura­se desenvolver  uma aplicação capaz de realizar a visualização gráfica dos dados de acidentes de trabalho que estão disponíveis no portal brasileiro de dados abertos

Microstructural characterization of U-7.5Nb-2.5Zr alloy after ageing and constrained fatigue

U-7.5Nb-2.5Zr cladded in Zircaloy-4 is one of the most studied fuel prototypes. The Nb and Zr are added to the U to stabilize the body-centered cubic (BCC) gamma phase and grant mechanical and swelling resistance. The U-7.5Nb-2.5Zr undergoes the gamma to α′′ phase transformation, generating compressive stresses due to the volume reduction. The α′′ phase also can transform to a combination of α + γ2 phase (equilibrium phases), which are known to be hard and brittle. This work had the objective to test the effect of ageing the gamma to α′′ phase in thermal cycling of a U-7.5Nb-2.5Zr cladded in Zircaloy-4 part. A co-laminated specimen was aged and thermally cycled in a dilatometry experiment. The samples were characterized through X-ray diffraction and metallography. The results show that the gamma to α′′ phase transformations occur at the begin- ning of the initial ageing, followed by stress relief. During the cycling, the sample demonstrated non-equal thermal strains and presented fractures along with the U matrix

UNDERWATER ROBOTIC VEHICLE FOR SHIP HULL INSPECTION: CONTROL SYSTEM ARCHITECTURE

Abstract. The inspection of underwater structure thickness has emerged as a