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The development of full-field measurement methods has enabled a new trend of heterogeneous mechanical tests. The inhomogeneous strain fields retrieved from these tests are being widely used in the calibration of constitutive models for sheet metals. However, today, there is no mechanical test able to characterize the material in a large range of strain states. The aim of this work is to present a heterogeneous mechanical test with an innovative tool/specimen shape, capable of producing rich heterogeneous strain paths and thus providing extensive information on material behavior. The proposed specimen is found using a shape optimization process where an index that evaluates the richness of strain information is used. In this work, the methodology and results are extended to non-specimen geometry dependence and to the non-dependence of the geometry parametrization through the use of the Ritz method for boundary value problems. Different curve models, such as splines, B-splines, and NURBS, are used, and C1 continuity throughout the specimen is guaranteed. Moreover, several deterministic and stochastic optimization methods are used in order to find the method or the combination of methods able to minimize the cost function effectively. Results demonstrated that the solution is dependent on the geometry definition, as well as on the optimization methodology. Nevertheless, the obtained solutions provided a wider spectrum of strain states than standard tests.

The scientific research devoted to modelling and simulation of water supply systems is, most of the times, dependent on the use of computer simulation programmes that requires a previous understanding on each specific programme particularities. At the same time, such programmes do not demonstrate to be open, with unconcealed data, simple and intuitive enough for teaching practices in the field of hydraulics. Therefore, other educational tools or approach should be taken. A numerical educative tool, developed in an Excel spreadsheet for the modelling and simulation of water networks operations is presented in this article. Intuitive and easy to adapt to several situations, the developed Excel-based tool presents large possibilities, not only for decisionsupport concerning the application of certain efficiency measures but also for pedagogical activities, allowing to understand with detail and immediately the effect of any control and/or design change in the daily operation of a water network, and hence in the associated daily energetic costs. Additionally, a number of analyses concerning the convenience of applying efficiency measures in such systems (namely the use of variablespeed pumps) is suggested and performed resorting to the developed tool. The developed tool has been applied in Fluid Mechanics classes with large success, demonstrating great potential for educational purposes.