IRIS - UNIRSM (Univ. degli Studi della Repubblica di San Marino)
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The MEM project: experiences, challenges and outcomes of an international double master-level degree
No full textEducating the workforce of the future to perform adeptly in the global environment as well as to surmount cross cultural boundaries is of a paramount necessity in today’s technologically advanced and complex settings. This environment has led institutions of higher education to seek international collaborations to face these challenges. Building on experiences and successes gained from a nearly decade long project entitled UMANE that was jointly supported by both the US Department of Education and the EU for undergraduate double/triple Bachelor’s degrees, this paper reports on an extension of the earlier partnership, to include a graduate level partnership that offers a double master degree between New Jersey Institute of Technology (NJIT) and University of Parma (UNIPR) that was put in place in 2015. In this work, we present the developed framework of this international cooperation, report on its challenges, and share our experiences. Specifically, the framework of the agreement establishes guidelines and course of study leading to double master degrees in the area of Engineering Management, one from NJIT and another from Parma University. Students in this program, usually, start their studies in Italy, attending the classes at their home Institution and then move to Newark, New Jersey, during the spring/second semester (6 months) of their first year, to attend NJIT classes. At the end of their studies, students will be awarded two master’s degrees in Engineering Management from the partnering universities
Inclusive University didactics and technological devices: a case study
No full textThis paper provides a review of projects related to new technologies used to favour the teaching-learning processes and the inclusive practices in the University context for students with disabilities and with Specific Learning Disorders. Authors present a review of strategies, trajectories and perspectives activated in the national and international scene, aiming to guarantee a significant pedagogical framework of reference. Furthermore, the paper focuses on a meaningful path activated at the University of Macerata, the project Inclusion 3.0, a relevant example of new technologies in support of teaching- learning processes and inclusion practices among all students
Modelling of Damaged Laminated and Sandwich Shell Structures by means of Higher-order Shear Deformation Theories
No full textThe main aim of the current research is the development of a mathematical formulation for the modelling of damage in laminated and sandwich composite shells. For this purpose, the damage of some areas of the structures can be seen as concentrated decays of the mechanical properties of the elastic constituents. In general, several kinds of damage can affect the mechanical behavior of a generic laminated structure, such as microcracking, debonding, fiber ruptures, and transverse matrix cracking, as specified in [1].
Without investigating the causes of the damage, the current approach suggests to introduce peculiar functions that multiply directly the mechanical properties of the elastic media, expressed in terms of engineering constants. To this aim, the Gaussian function and an ellipse shaped law are used to model a quick variation of the mechanical properties within the whole structural domain. By setting properly the parameters that characterize these distributions, it is possible to control the intensity of the deterioration and the width of the damaged areas, as well as the point of applications.
The present approach is employed to characterize the damage in some doubly-curved shells characterized by different radii of curvature. The difficulties related to the description of these curved surfaces are overcome by means of an analytical formulation based on differential geometry [2]. As far as the mechanical properties are concerned, several constituents are considered and combined.
The theoretical framework is based on a formulation that allows to develop easily different kinematic models and expansions in a unified manner. Thus, several Higher-order Shear Deformation Theories, which can include also the zig-zag effect, are employed. In fact, it has been proven that peculiar mechanical configurations require an enriched structural model, since lower-order theories could be inadequate to capture the effective mechanical behavior.
Finally, a numerical technique able to solve the strong form of the governing equations is used. For this purpose, the partial derivatives that appear in the fundamental system are directly approximated through the Generalized Differential Quadrature method due to its accuracy [3].
References
[1] Tornabene, F., Fantuzzi, N., Bacciocchi, M., “Linear Static Behavior of Damaged Laminated Composite Plates and Shells”, Materials, 10, 811, 1-52 (2017).
[2] Tornabene, F., Fantuzzi, N., Bacciocchi, M., and E. Viola, Laminated Composite Doubly-Curved Shell Structures. Differential Geometry. Higher-order Structural Theories, Esculapio, Bologna (2016).
[3] Tornabene, F., Fantuzzi, N., Ubertini, F., Viola, E., “Strong Formulation Finite Element Method Based on Differential Quadrature: A Survey”, Applied Mechanics Reviews, 67, 020801-1-55
An Innovative Numerical Approach for the Mechanical Analysis of Damaged Laminated Composite Structures
No full textThe main aim of the present work is to develop an efficient and reliable computational approach to deal with the structural analysis of damaged laminated composite plates and shells. For this purpose, the strong formulation of the governing equations is numerically solved by means of the Generalized Differential Quadrature (GDQ) method, due to its superior features. Thus, the system of differential equations, which is obtained in the theoretical framework of Higher-order Shear Deformations Theories (HSDTs), is directly approximated by applying the GDQ principles. An innovative strategy is presented to model the variable mechanical properties of the considered structures. In particular, if the variation in hand is properly set up to obtain a localized rapid decay of the mechanical properties, a damaged configuration can be studied. To this aim, the engineering constants that describe the mechanical properties of orthotropic layers are multiplied by a reducing function, which can be analytically defined by the Gaussian function or by an ellipse shaped law. The effects of such damages are studied through a massive set of parametric investigations in order to show the influence of the damage parameters on the structural response. Several geometries are analyzed as well
Strong and Weak Formulations for the Analysis of Arbitrarily Shaped Laminated Composite Structures
No full textA numerical approach is developed to deal with arbitrarily shaped structures. Two different methodologies are used to this aim, which are based on the Differential Quadrature and Integral Quadrature methods, respectively. These numerical methods are able to approximate both derivatives and integrals [1]. Therefore, the strong and weak formulations of the governing equations can be solved. As shown in the paper [2], these approaches are accurate, reliable and stable, when employed to obtain the mechanical response of various kinds of structures, such as plates, shells and membranes. In particular, their effectiveness is proven by means of the comparison with the analytical solutions available in the literature, both for isotropic and composite structures.
With respect to other approaches such as the Finite Element Method (FEM), the proposed methodologies are able to get the solution with few degrees of freedom. In addition, the convergence behavior is faster than the FEM.
A domain decomposition based on Isogeometric analysis is developed to analyze the mechanical behavior of arbitrarily shaped structures. The so-called blending functions are used to deal with discontinuities and distortions by means of a reduced number of elements [3, 4]. Thus, a nonlinear mapping is achieved by employing NURBS curves. According to the numerical method used in the computation, the strong and weak formulations are solved within each element. The effect of distorted meshes on the solution is investigated, as well. The numerical methods at issue are named Strong Formulation Finite Element Method (SFEM) and Weak Formulation Finite Element Method (WFEM).
References
[1] Tornabene, F., Fantuzzi, N., Ubertini, F., Viola, E., "Strong Formulation Finite Element Method Based on Differential Quadrature: A Survey", Applied Mechanics Reviews, 67, 02081-1-55 (2015).
[2] Tornabene, F., Fantuzzi, Bacciocchi, M., "Strong and weak formulations based on differential and integral quadrature methods for the free vibration analysis of composite plates and shells: Convergence and accuracy", Engineering Analysis with Boundary Elements. In press. DOI: 10.1016/j.enganabound.2017.08.020.
[3] Fantuzzi, N., Tornabene, F., "Strong Formulation Isogeometric Analysis (SFIGA) for Laminated Composite Arbitrarily Shaped Plates", Composites Part B - Engineering, 96, 173-203 (2016).
[4] Tornabene, F., Fantuzzi, Bacciocchi, M., "The GDQ Method for the Free Vibration Analysis of Arbitrarily Shaped Laminated Composite Shells Using a NURBS-Based Isogeometric Approach", Composite Structures, 154, 190-218 (2016)
VENTURE CAPITAL FOR THE ENTREPRENEURIAL UNIVERSITY: A TEXT MINING REVIEW OF THE LITERATURE
No full textCritical Velocity Evaluation of Rotating Laminated Composite Doubly-Curved Shells
No full textThis research aims to investigate the dynamic behavior of rotating shells. This topic is extremely innovative and deserves to be studied in depth, especially as far as doubly-curved geometries are concerned. In fact, the few papers that deal with this structural problem are limited to singly-curved shells of revolution, such as cylinders and cones. In contrary, the proposed formulation can easily describe the dynamic behavior of shell structures characterized by variable radii of curvature. In addition, a completely general rotating mechanism can be studied, since the angular velocities can be indifferently applied along each principal direction of the three-dimensional space. A combination of more velocity components can be applied as well. A massive set of parametric investigations is performed to evaluate the critical velocities of different rotating structures. This parameter, in fact, is important in shell design, in order to avoid instability phenomena. From the mechanical point of view, several advanced constituents are analyzed, such as laminated and granular composites. The theoretical framework is based on Higher-order Shear Deformation Theories (HSDTs). The solution of the dynamic problem in hand is solved numerically by means of the Generalized Differential Quadrature (GDQ) method, due to its accuracy, stability, and reliability features. The proposed approach is validated through the comparison with the results available in the literature for simpler geometries