Mining and Tailings Dam Detection in Satellite Imagery Using Deep Learning.

This work explores the combination of free cloud computing, free open-source software, and deep learning methods to analyze a real, large-scale problem: the automatic country-wide identification and classification of surface mines and mining tailings dams in Brazil. Locations of officially registered mines and dams were obtained from the Brazilian government open data resource. Multispectral Sentinel-2 satellite imagery, obtained and processed at the Google Earth Engine platform, was used to train and test deep neural networks using the TensorFlow 2 application programming interface (API) and Google Colaboratory (Colab) platform. Fully convolutional neural networks were used in an innovative way to search for unregistered ore mines and tailing dams in large areas of the Brazilian territory. The efficacy of the approach is demonstrated by the discovery of 263 mines that do not have an official mining concession. This exploratory work highlights the potential of a set of new technologies, freely available, for the construction of low cost data science tools that have high social impact. At the same time, it discusses and seeks to suggest practical solutions for the complex and serious problem of illegal mining and the proliferation of tailings dams, which pose high risks to the population and the environment, especially in developing countries.

Soft-tissue simulation using LEM--Long Elements Method.

This paper discusses the use of the Long Elements Method--LEM in soft tissue modeling and surgery simulation. The LEM is a new method for real time, physically based, dynamic simulation of deformable objects, based on a new meshing strategy, using long elements. The method uses a combination of static (state-less) and dynamic approaches to simulate deformations and dynamics, obtaining a higher degree of compliance per time step. Global deformations that conserve volume and are convincingly compliant are obtained. Models are defined using bulk material properties. Elastic and plastic deformations can be simulated. The real time performance of the method and its intrinsic properties of volume conservation, modeling based in material properties and simpler meshing make it particularly attractive for soft tissue modeling and surgery simulation.