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This work is authored by a group of Ph.D. students and academics who attended a workshop on visual methodologies in the framework of the Scuola di alta formazione in geografia organised by AGeI (Association of Italian Geographers), 2022 edition. By visually reporting the workshop activities we aim at reflecting on the creative power of images in expanding geographical imaginations and its potential in the teaching of geography. The paper is shaped as a visual essay in which images and text do not refer directly to each other but rather aim at creating an imaginative reading flow.

A low input current total harmonic distortion (THD) rectifier is presented, tailored around an open-end winding permanent magnet synchronous generator. Specifically, a six-level converter topology is obtained by connecting the generator stator winding to a three level T-type unidirectional rectifier on one side, and to an auxiliary two-level inverter on the other side. The T-type rectifier manages the entire active power stream and operates at the line frequency in order to minimize the switching power losses. The auxiliary inverter is instead driven by a standard PWM technique, being tasked to sinusoidally shape the input current and to actively balance the voltage across the dc-bus capacitors of the T-type rectifier. Such an inverter, being rated at a lower power and at a lower voltage than the T-type rectifier, can exploit low-cost power mosfet s. The proposed topology, featuring a very low input current THD, could well supplement in aircraft, portable or distributed generation applications, modern high-speed permanent magnet synchronous generators featuring a quite small stator impedance. Simulation and experimental results confirm the effectiveness of the proposed configuration.

The paper describes the approach followed in the characterization of the structural behavior of the historical masonry church of San Filippo Neri in Macerata, severely damaged and condemned after the Central Italy Earthquake occurred in October 2016. The case study of San Filippo Neri is particularly interesting: first for the historical and artistic importance of the churchfurthermorefor the evidences of recurrent structural damage. The laboratory of Proof and Research on Structures and Materials of Roma Tre University carried out an extensive onsite testing campaign - including geometric survey, flat-jack test and ambient vibration test - in order to investigate the state of the building. Operational modal analysis was used to assess the dynamic behavior of the church; the results of the testing campaign were interpreted and correlated with an accurate finite element model of the construction. The numerical model was finally tuned up based on the experimental results in order to match the dynamic behavior. The aim of the research is to set the first steps for an integrated approach able to fit and combine the resultsfrom experimental onsite testing and numerical modelling.