An Equi-Dimensional Finite Element Approach for Flow Problems in Fractured Porous Media

We propose a novel approach for flow simulations in fractured porous media based on an equi-dimensional representation of the fractures and a standard continuous finite element (FE) method. We employ an adaptive mesh refinement strategy to automatically adjust an initial regular mesh to any fracture distribution with a desired accuracy. The proposed approach is easily implementable in any FE software, does not involve the coupling of different discretizations, and provides symmetric and positive definite stiffness matrices. We provide a systematic validation of our method and we show that it can be used to simulate fluid flow for fracture networks of realistic complexity

Past&Present at Tarchna&Tarquinia: a flexible approach to make visible the invisible

This contribution falls within the topic of the “development of guidelines and best practices” and deals with the study case of the ancient Etruscan city of Tarchna (Tarquinia, central Italy). The “Tarquinia Project” started here in 1982 with the investigations carried out by the Università degli Studi di Milano in two sacred areas and along the fortifications. The Project was endowed since its beginnings with the collaboration of several experts in disciplines other than Archaeology which number has increased in the past years. Their aim is to find out as much as possible about the material aspects of Archaeology to decode their relationship with the invisibility of ancient life. This contribution aims at presenting our approach addressed to put scholars in the condition to handle data according to their own procedures, within the same environment, through an ecosystem of benchmarks and references in ways close to the individual practices, supported by ICTs. This is meant to avoid the use of predetermined terminologies and categories, enhancing the proper methods of every single discipline involved in a multidisciplinary environment, beyond the current work of every individual scholar. We propose a radical change of perspective, starting from the collection of raw data in several fields (material aspects of Archaeology, Geoarchaeology, Architecture, Topography) to grasp the underlining model, thanks to the assessment of recurrent associations among different categories of evidence, instead of starting from preconceived theoretic models and using data to confirm them. Distinct small, medium and large scale investigation methods are integrated for the first time to produce a significant interdisciplinary cognitive tool to shift from the materiality of the leftovers of Ancient Past, to its integrity, to what lies behind at a metaphysical level and is, therefore, invisible to us. This is related to the materiality of rituals, based on the recurrence of cultic practices in the above-mentioned sacred areas, whose gestures might also be revealed by sediments and organic remains, in addition to other archaeological and epigraphic issues. Tarquinia strongly challenges researchers to be open to unconventional and unexploited issues due to the complexity of the site. It is the ideal place to create awareness among the general public about the results of Archaeological research and to disseminate and make visible its acquirements, according to the European Charter for Researchers. The support of Environmental Psychologists helps to ensuring outreach entails initiatives directed to the local population, in order to introduce them to an equilibrated connection between their invisible Past and the local present culture. In this framework students from high school are involved in the Archaeological field activities, since 2012. Our best practices are therefore addressed to give back to the ancient Etruscan city its value of prominent cultural and natural landmark in the Past, to make it possible for the modern community to assess it in the same way. According to current theories of “place identity” and "place attachment" the modern community is in the condition to feeling and experiencing the continuity between past, present and future

Verification of cardiac mechanics software: benchmark problems and solutions for testing active and passive material behaviour

Models of cardiac mechanics are increasingly used to investigate cardiac physiology. These models are characterized by a high level of complexity, including the particular anisotropic material properties of biological tissue and the actively contracting material. A large number of independent simulation codes have been developed, but a consistent way of verifying the accuracy and replicability of simulations is lacking. To aid in the verification of current and future cardiac mechanics solvers, this study provides three benchmark problems for cardiac mechanics. These benchmark problems test the ability to accurately simulate pressure-type forces that depend on the deformed objects geometry, anisotropic and spatially varying material properties similar to those seen in the left ventricle and active contractile forces. The benchmark was solved by 11 different groups to generate consensus solutions, with typical differences in higher-resolution solutions at approximately 0.5%, and consistent results between linear, quadratic and cubic finite elements as well as different approaches to simulating incompressible materials. Online tools and solutions are made available to allow these tests to be effectively used in verification of future cardiac mechanics software