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- International Conference on Mathematical Analysis and Applications in Science and Engineering – Book of Extended AbstractsPublication . Pinto, C.M.A.; Mendonça, Jorge; Babo, Lurdes; Baleanu, DumitruThe present volume on Mathematical Analysis and Applications in Science and Engineering - Book of Extended Abstracts of the ICMASC’2022 collects the extended abstracts of the talks presented at the International Conference on Mathematical Analysis and Applications in Science and Engineering – ICMA2SC'22 that took place at the beautiful city of Porto, Portugal, in June 27th-June 29th 2022 (3 days). Its aim was to bring together researchers in every discipline of applied mathematics, science, engineering, industry, and technology, to discuss the development of new mathematical models, theories, and applications that contribute to the advancement of scientific knowledge and practice. Authors proposed research in topics including partial and ordinary differential equations, integer and fractional order equations, linear algebra, numerical analysis, operations research, discrete mathematics, optimization, control, probability, computational mathematics, amongst others. The conference was designed to maximize the involvement of all participants and will present the state-of- the-art research and the latest achievements.
- International Conference Mathematical Analysis and Applications in Science and Engineering, ISEP, Porto, Portugal, June 20-22, 2024: Book of abstractsPublication . Golubitsky, Martin; Lacarnobara, Walter; Pinto, Carla M.A.; Babo, Lurdes; Mendonça, Jorge; Carvalho, Fernando; Rocha, Rui
- Book of Abstracts of the First International Conference - Building Bridges in STEAM Education in the 21st CenturyPublication . Soares, Filomena Baptista; Lopes, Ana Paula; Pinto, Carla; Mendonça, JorgeThe International Conference BBC'22 aims to provide an opportunity for all academic and non-academics to share their personal experiences and projects, presenting their contributions and getting feedback from other attendees.
- Modified SIQR model for the COVID‐19 outbreak in several countriesPublication . Pinto, Carla M. A.; Tenreiro Machado, J. A.; Burgos‐Simón, ClaraIn this paper, we propose a modified Susceptible-Infected-Quarantine-Recovered (mSIQR) model, for the COVID-19 pandemic. We start by proving the well-posedness of the model and then compute its reproduction number and the corresponding sensitivity indices. We discuss the values of these indices for epidemiological relevant parameters, namely, the contact rate, the proportion of unknown infectious, and the recovering rate. The mSIQR model is simulated, and the outputs are fit to COVID-19 pandemic data from several countries, including France, US, UK, and Portugal. We discuss the epidemiological relevance of the results and provide insights on future patterns, subjected to health policies.
- Probabilistic analysis of a foundational class of generalized second-order linear differential equations in classic mechanicsPublication . Burgos, C.; Cortés, J.-C.; López-Navarro, E.; Pinto, C.M.A.; Villanueva, Rafael-J.A number of relevant models in Classical Mechanics are formulated by means of the differential equation y′′(t)+Atβy(t)=0 . In this paper, we improve the results recently established for a randomized reformulation of this model that includes a generalized derivative. The stochastic analysis permits solving that generalized model by computing reliable approximations of the probability density function of the solution, which is a stochastic process. The approach avoids constructing these approximations from limited statistical punctual information and the Principle of Maximum Entropy by directly constructing a sequence of approximations using the Probabilistic Transformation Method. We prove that these approximations converge to the exact density under mild conditions on the data. Finally, several numerical examples illustrate our theoretical findings.
- A model for type I diabetes in an HIV-infected patient under highly active antiretroviral therapyPublication . Chávez, Joseph Páez; Wijaya, Karunia Putra; Pinto, Carla M. A.; Burgos-Simón, ClaraType 1 diabetes (T1D), previously known as juvenile diabetes or insulin-dependent diabetes, is an autoimmune disease characterized by the insufficient (or lack of) production of insulin by the pancreas. Insulin is crucial to maintain blood sugar at healthy levels. High blood sugar damages the body and causes a variety of symptoms, ranging from severe thirst, fatigue, to urinary infections. The cells responsible for the production of insulin are the -cells. In T1D, these are killed by an abnormal response of the immune system. Specific clones of cytotoxic T-cells invade the pancreatic islets of Langerhans, and eliminate them. T1D diabetes may develop in human immunodeficiency virus (HIV)-infected patients, though in rare situations. In this paper, we propose a cell model for the development of T1D in these patients, after immune restoration, during highly active antiretroviral therapy (HAART). The study includes the derivation of the qualitative properties of the model, and its comprehensive investigation via path-following methods, using the continuation platform COCO. In this way, the main theoretical predictions are verified in detail. Furthermore, this numerical part establishes accurate parameter thresholds to ensure an effective disease treatment in HIV-infected persons to prevent the development of T1D.
- Design of auxiliary model based normalized fractional gradient algorithm for nonlinear output-error systemsPublication . Chaudhary, Naveed Ishtiaq; Khan, Zeshan Aslam; Kiani, Adiqa Kausar; Raja, Muhammad Asif Zahoor; Chaudhary, Iqra Ishtiaq; Pinto, Carla M. A.A new avenue of fractional calculus applications has emerged that investigates the design of fractional gradient based novel iterative methods for analyzing fractals and nonlinear dynamics in solving engineering and applied sciences problems. The most discussed algorithm in this regard is fractional least mean square (FLMS) algorithm. This study presents an auxiliary model based normalized variable initial value FLMS (AM-NVIV-FLMS) algorithm for input nonlinear output error (INOE) system identification. First, NVIV-FLMS is presented to automatically tune the learning rate parameter of VIV-FLMS and then the AM-NVIV-FLMS is introduced by incorporating the auxiliary model idea that replaces the unknown values of the information vector with the output of auxiliary model. The proposed AM-NVIV-FLMS scheme is accurate, convergent, robust and reliable for INOE system identification. Simulation results validate the significance and efficacy of the proposed scheme.
- Use of Hands-on and Remote Lab with an Inquiry-Based Approach to Learn Statistics in EngineeringPublication . Zannin, Marcelo; Lima, Natércia; Pinto, CarlaPractical activities are an effective way to contextualize concepts and motivate students. This article reports on an innovative use of hands-on and remote labs in a theoretical course of Statistics for engineering undergraduates. The lecturer used an inquiry-based approach to center learning around students. The problems proposed revolved around basic concepts of circuit theory: how reliable are resistance values and how does a resistor behave in an electric circuit. Students collected data and learned statistics while attempted to address the problems. We report on two implementations done in 2017, at Universidade Federal de Santa Catarina (Brazil), where 68 students concluded the course. We investigated the effects of such strategy, analyzing assessment results, attendance and accesses to the remote lab. We also surveyed the lecturer and students on the methodology and the use of the remote lab. Our results show that students and lecturer had positive views on the experience and suggest that students felt motivated to collaborate and learn statistics. We also found correlation among grades in lab activities and final grades, which shows the hands-on activities had a positive impact on students' academic performance.
- Analyzing the Implementation of Lean Methodologies and Practices in the Portuguese Industry: A SurveyPublication . Pinto, Carla; Mendonça, Jorge; Babo, Lurdes; Silva, Francisco J. G.; Fernandes, José L. R.The mass production paradigm on which much of the industry was based has changed. The market is increasingly demanding, requesting diversity and products that are more and more adapted to personal wishes and requirements. This implies producing a greater diversity of products in smaller quantities. Competitiveness is enormous, which forces most companies to be truly effective and efficient, taking care of product quality, delivery time, and final cost. Lean methodologies have been a valuable aid in this field. The diversity of Lean tools has been shown to have answers to the most diverse challenges, and companies are aware of this, increasingly adopting methodologies and processes that aim to progressively reduce waste and adapting their production paradigm to what the market requires. This work intends to provide a vision, as global as possible, of the pathway of Lean implementation in the Portuguese industry. For this purpose, a survey was carried out with a significant sample of Portuguese industrial companies from a wide range of activity sectors. The data collected through the survey were treated statistically, and then a SWOT analysis of the results was performed, which provided a collection of precious information on the evolution of industrial companies in Portugal
- Analyzing the Implementation of Lean Methodologies and Practices in the Portuguese Industry: A SurveyPublication . Pinto, Carla M. A.; Mendonça, Jorge; Babo, Lurdes; Silva, Francisco J. G.; Fernandes, José L. R.The mass production paradigm on which much of the industry was based has changed. The market is increasingly demanding, requesting diversity and products that are more and more adapted to personal wishes and requirements. This implies producing a greater diversity of products in smaller quantities. Competitiveness is enormous, which forces most companies to be truly effective and efficient, taking care of product quality, delivery time, and final cost. Lean methodologies have been a valuable aid in this field. The diversity of Lean tools has been shown to have answers to the most diverse challenges, and companies are aware of this, increasingly adopting methodologies and processes that aim to progressively reduce waste and adapting their production paradigm to what the market requires. This work intends to provide a vision, as global as possible, of the pathway of Lean implementation in the Portuguese industry. For this purpose, a survey was carried out with a significant sample of Portuguese industrial companies from a wide range of activity sectors. The data collected through the survey were treated statistically, and then a SWOT analysis of the results was performed, which provided a collection of precious information on the evolution of industrial companies in Portugal.