Prof. Maria Nogal (University of Cantabria, Spain) presents "Observability Techniques Applied to Structural System Identification"

Friday, November 15, 2013

Dr. Adel El Safty (UNF Civil Engineering) has invited a special guest, Professor Maria Nogal, Ph.D. (Department of Applied Mathematics and Computational Sciences at the University of Cantabria, Spain), to present her research in a lecture, titled "Observability Techniques Applied to Structural System Identification."  The presentation will take place at 9 a.m. on Friday, 15 November 2013, in Building 050, Room 1406.


ABSTRACT

This seminar deals with the problem of applying observability techniques to Structural System Identification, understanding as such the problem of identifying which is the subset of characteristics of the structure, such as Young's modulus, area, inertia and/or product of them (flexural or axial stiffnesses), that can be uniquely defined when an adequate subset of deflections, forces and/or moments in the nodes is provided. Compared with other standard observability problems, two issues arise here. First, nonlinear unknown variables (products or quotients of elemental variables) appear, that is, systems of polyrational equations, and second, the mechanical and geometrical properties of the structure are “coupled" with the deflections and/or rotations at the nodes. In fact, it is demonstrated that polyrational equations are of primary importance and arise in all fields of Science and Engineering and that it is not a coincidence but the result of well-defined and physically based equations. To solve these polyrational equations a direct method is proposed in this seminar. The results obtained show, for the very first time, how observability techniques can be efficiently used for the identification of structural systems and damage detection. Some examples are given to illustrate the proposed methodology and to demonstrate its power for the case of static measures.


Professor Nogal's Bio.