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- MIARforest Reproducibility and Reliability for Assessing Occupational Risks in the RainforestPublication . Lima, Killian; Castro, Ana C. Meira; Baptista, J. SantosThe Method for the Integrated Assessment of Risks for rainforest (MIARforest) is a specific methodology for assessing the risk of occupational accidents associated with working in native tropical forests. MIARforest was validated for the results’ reproducibility and the reliability of calculated risk levels through the Delphi approach. Two rounds of questionnaires illustrating ten scenarios of activities associated with the logging process in the Eastern Amazon’s native rainforest (Brazil) were presented to forestry and occupational health and safety (OHS) experts. In the first round, the questionnaire was answered anonymously by 55 experts, and in the second, by 46. A percentage of agreement of at least 80% in each question was considered to close the process. Questions that did not meet the criterion in the first round were reassessed in the second round. The obtained results lead to the conclusion that MIARforest, an occupational accident risk assessment tool, has been effectively validated, demonstrating inter-rater reproducibility and reliability in determining risk values. These results highlight the objectivity and reliability of MIARforest.
- Occupational Risk Assessment in Native Rainforest Management (MIARforest)—Parameters Definition and ValidationPublication . Lima, Killian; Meira Castro, Ana C.; Baptista, João SantosMaintaining native rainforests as a sustainable ecosystem and their resilience to external pressures involves their economic profitability as a natural resource of unique and renewable products. For this purpose, new approaches have been developed and refined. This work seeks to contribute in this direction in the context of occupational safety and health (OSH) by presenting a new method for integrated assessment of risks for rainforests (MIARforest). The MIARforest is based on the MIAR, a method that has shown promising results in occupational risk assessment in different industrial sectors. Its parameters were discussed and assessed to improve their relevance, wording and risk assessment through the Delphi methodology by a panel of 62 experts in forestry and OSH who responded independently to questionnaires made available through Google Forms. A consensus of over 79% among the experts was reached in two rounds. This result highlights the high objectivity and the low percentage of dubious possible interpretations of the parameters and sub-parameters of this occupational risk assessment method.
- Occupational accidents in native and planted forests in Brazil: 2007–2018Publication . Lima, Killian S.; Meira Castro, Ana C.; Torres Costa, J.; Baptista, J. SantosBACKGROUND:Despite constant technological evolution, the forestry sector is still characterised as one with the highest risk of occupational accidents. There is no doubt that accidents penalise workers considerably, as well as the companies, insurers, and, consequently, the society, to which many of the costs are externalised, namely in cases where the worker is incapacitated and unable to work. OBJECTIVE:The aim of this work is to analyse data on occupational accidents in forestry operations in Brazil between 2007 and 2018 in both native and planted forests. METHODS:Data were made available by the Brazilian Statistical Directory of Accidents at Work. RESULTS:The results show that, although most accidents occurred in planted forests, mortality was higher in native forests. It was also found that, overall, the rate of serious accidents resulting in an incapacity to work and, consequently, sick leave is considerably high. CONCLUSIONS:These results highlight that integrating an occupational safety system into a forest management system is crucial for reducing work-related accidents in both native and planted forests. However, the success of this measure will only be effective if it is accompanied by a review of both the Brazilian labour policy and the Brazilian occupational safety management policy, to ensure compliance with legislation, mainly on the part of outsourced companies.
- Local Factors Controlling Gully Development in a Mediterranean EnvironmentPublication . Martins, Bruno; Nunes, Adélia; Meira-Castro, Ana C.; Lourenço, Luciano; Hermenegildo, CarlosGullies contribute very efficiently to soil loss and degradation, particularly in Mediterranean environments. While natural factors are involved in gully formation and further development, anthropic action is almost always an element. Knowledge of formation and development factors are important if soil protection strategies and measures are to be effective. In this paper, we identify the most important factors in the development of gullies in a Mediterranean setting based on a study of the Alva gully (central Portugal). Its development in the last four years is examined, based on a study of the modification of its morphological characteristics. The analysis was based on principal component analysis (PCA) to estimate the correlation between the quantitative characteristics, geomorphological processes, and biophysical variables. The results show that the main factors that seem to control the spatial variation of soil erosion are the soil penetration resistance, slope, slope shape, and vegetation cover.
- 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.
- In memory of Professor José António Tenreiro Machado (1957–2021)Publication . Pinto, Carla M. A.; Lopes, António M.; Galhano, Alexandra M. S. F.Professor José António Tenreiro Machado (Fig. 1) was born on October 6, 1957, in Pinhel, Portugal, and passed away, unexpectedly on October 6, 2021. At the age of two, after his mother separated from his father, he and his mother went to live with his maternal grandparents in Porto. His grandparents were his family pillars. At the age of fifteen, his grandmother died of cancer and, two years later, his grandfather got remarried. In high school, he became an excellent student and started giving private lessons to other high school students, while continuing his studies. As a university student, he carried on tutoring his university peers. With this income, he paid his studies and also helped his mother financially. During the same period, he was a chess player and won many trophies. He finished his Electrical Engineering degree with the highest classification and received the Eng∘ Cristiano P. Spratley award from the University of Porto.
- 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.
- 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.
- 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.