Multi-scale techniques for mansonry structures

The aim of this work is, hence, to adopt the computational homogenization techniques to obtain the global response of masonry structures. Since the experimental global response curves, obtained in typical shear tests on masonry panels, show stiffness and resistance degradation, damage is the fundamental ingredients which must be taken into account in such problems. Moreover, as it is well known, due to the aforementioned softening behavior, regularization techniques are required in order to avoid spurious mesh dependencies when a numerical solution is sought in the framework of finite element method. The first step of this work is the adoption of the standard first order computational homogenization, where Cauchy continuum is used both at the macro and micro-level. This approach is well known in literature and several authors applied it to different engineering problems. An example of the adoption of regularization techniques in the context of multi-scale approaches is found in Massart (2003). Hence a regularization based on the imposition of the macroscopical length scale at the micro-level, in the framework of the fracture energy regularization, is proposed. However, as previously stated, many authors have pointed out the inner limits of first order computational homogenization. Such a formulation, in fact, may be adopted only if 1)the microstructure is very small with respect to the characteristic size at the macro-scale; 2)the absolute size of the constituents does not affect the mechanical properties of the homogenized medium and in presence of low macroscopic gradients of stresses and strains. As a consequence no localization phenomena typically exhibited by masonry can be analyzed. For masonry structures, instead, microstructural typical sizes are comparable with the macro-structural sizes; shape, size and arrangement of the constituents strongly affect the mechanical global response and high deformation gradients typically appear. An enriched formulation is then proposed in order to overcome these problems, based on the adoption of a Cosserat medium at the macro-level and a Cauchy medium at the micro-level. The theoretical and computational schemes remain the same as before but for the fact that the two media present different variables. In particular in the Cosserat medium additional strain and stress variables appear, with respect to the Cauchy continuum, as a consequence of the independent rotational degree of freedom assigned to every material point. Thus, a more sophisticated kinematic map, containing higher order polynomial expansions, is needed to state proper bridging conditions between the two levels. The innovative contribution of this work concerns the adoption of an enhanced multi-scale computational homogenization technique for studying the masonry response, together with the employment of damage models for the constituents description. Thus, by exploiting the inner regularization properties of the Cosserat continuum at the macro-level and by adopting a classical fracture energy regularization at the micro-level, localization phenomena, typically exhibited by masonry structures, are analyzed. Since this material shows a typical strain softening behavior, an ad hoc regularization technique has been developed at both levels in order to obtain objective numerical responses. To the knowledge of the author, no previous examples of Cosserat-Cauchy computational homogenization techniques, taking into account localization effects, have been presented. A possible objection to the use of a fully-coupled multi-scale technique could be related to the high computational efforts required, but here the use of parallel computing brings them down. In this context, these procedures strike a good balance between the achievement of detailed information at the scale of the constituents and the requirement of holding the computational costs down

Estimativa de diversidade genética de Cedro (Meliaceae), uma espécie ameaçada.

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Shift for engineering horizons

Science, Engineering and Technology cross nearly every facet of modern life and, as problem solvers, engineers are perfectly capable of managing entrepreneurial activities, mastering innovative ways of business development, when they spend time and efforts understanding and acting in the field. Engineers rely on science and methods for analysis to ensure the quality and liability of design; nevertheless a pinch of creativity is required in order to find innovative solutions for economic and entrepreneurial problems. So, at present, engineers with technical skills must also learn how to work in interdisciplinary teams, how to develop designs rapidly, how to manufacture sustainably, how to combine art and engineering and how to address global markets. Providing opportunities in the work market for future engineers has become now part of university training, as a way to assure also the future competitiveness of universities. In many places, enterprises and universities have still difficulties in working together, it is up to engineering schools and universities to have the initiative to enhance their programs, to assure the proper training for future professionals that can perform in this mutant work environment of the 21st Century. According to the report “The Engineer of 2020”, developed by the National Academy of Engineering, USA, which paints a picture of a dynamically changing and evolving world: “The successful future engineer will need strong analytical skills, practical ingenuity, creativity, good communication skills, business and management knowledge, leadership, high ethical standards, professionalism, dynamism, agility, resilience, flexibility, and the pursuit of lifelong learning”. Currently, the opportunities for professionals seem to be very narrow, once economic crisis is impacting countries and communities worldwide, as the result of a natural cyclic wave of economy, until a new economic model starts to work somehow. To provide future professionals an opportunity in the work market has now become part of university training as a way to assure the future of university. COPEC – Science and Education Research Council’s education research team has designed and implemented a program for engineering students which is called “Working with Communities Course”, providing 3rd year engineering students the chance to work as consultants for the entrepreneurial community in the city. The goal is to offer a space that has been named “Innovative Office”, to which local entrepreneurs can resort to in order to discuss and to find sustainable solutions for a specific problem or project. The choice of the name working with communities was due to the enticing appeal once as young “green generation” they want to cooperate with society segments in any way. However the true goal is to give them a chance to have a professional experience and also some time of internship although early in the program. As they work using their creativity to design and present solutions within the constraints of ethical practice grounded in science and engineering methods and standards, they can evaluate the reality of professional practice and see if engineering is really what they want to pursue as a career. They have to work using their creativity to design and present solutions within the constraints of ethical practice grounded in science and engineering methods and standards. The process involves face-to-face meetings and discussions with entrepreneurs of the city, from the presentation of the problem until the delivery of the plans. Once engineers are part of society it is important that they have a stronger interaction with the wider public. So the goal of including this course in the program is to provide students the opportunity to work closely with the real local entrepreneurship environment. Apart from this, engineers need to develop broad fundamental understanding of their professional responsibilities, as well as the need to be entrepreneurial in order to understand and contribute in the context of market and business pressures. If engineers can work with the public to explain how engineering can help address their problems, and to help them to decide which are the most effective and affordable ways to address their concerns, the community can make great progress and improvements. It will surely be a great acquisition for the city business community as well as for the students themselves, once they can get a glimpse of what it is to engineer in real world. This project has the chance developed in partnership with a City Hall as a way to improve entrepreneurship in the region, aiming at fostering employment and private initiatives to change community’s profile. It is an immersive period of internship, in real engineering work environment.Competitivity Factors Operational Programme - COMPETE: POCI-01-0145-FEDER-007136Competitivity Factors Operational Programme - COMPETE: POCI-010145-FEDER-007043FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/201

Innovative on demand international engineering programs

Following the new trends of higher education, COPEC International Institute of Education is offering courses in engineering that are customized not only for enterprises but also for groups of professionals or academia interested in acquiring special knowledge with a valid certification. The programs are dimensioned in accordance with the knowledge and practice that are necessary for the group of professional engineers or academia. They make the requirements and the program is designed to fit their needs. They are partially on class and some content is delivered on line as long as it comprises the amount of hours that are necessary to accomplish the program, focusing in the main goal that is to have a certified course of specialists in a certain field of expertise. The proposed program is an investment that guarantees return by the strategic vision for a successful performance, the higher management capacity and the growth of intellectual capital.This work is funded by FEDER funds through the Operational Program for Competitiveness Factors (COMPETE) and National Funds through FCT - Foundation for Science and Technology under the Project: FCOMP-01-0124-FEDER-022674 and PEst-C/CTM/UI0264/2013

Focusing the future of engineering education

The definitions of teacher and student are changing and Education is moving out of episodic experiences at traditional institutions like classrooms and schools into learning flows that course through our daily lives. The use of new technologies in classroom is also an important requirement for a teacher in Higher Education especially in engineering; it is part of teaching environment now. So utilizing emerging technologies to provide expanded learning opportunities is critical to the success of future generations. It is clear that there is a life long learning environment not only for future engineers but also for teachers. This paper describes the "International Engineering Educator" developed by the engineering education research team of COPEC – Science and Education Research Council. It is offered by the International Institute of Education of COPEC, which is a certification organization that certifies in accordance with the Ministry of Education of the Country referring to the National Law of Higher Education, with an international certification.This work is funded by FEDER funds through the Operational Program for Competitiveness Factors (COMPETE) and National Funds through FCT - Foundation for Science and Technology under the Project: FCOMP-01-0124-FEDER-022674 and PEst-C/CTM/UI0264/2013