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- Novel insights into activated carbon derived from municipal solid waste for CO2 uptake: synthesis, adsorption isotherms and scale-upPublication . Karimi, Mohsen; Zafanelli, Lucas F.A.S.; Almeida, João P.; Ströher, Gylles R.; Rodrigues, Alírio; Silva, José A.C.Recently, developing bio-based carbon materials due to the surface chemistry and a large spectrum of pore structures have received much attention. In the present work, a series of activated carbon (AC) adsorbents were synthesized from the compost derived by the mechanical/biological treatment of municipal solid wastes and evaluated regarding their CO2uptake. The AC samples were characterized by sulfuric acid and calcination by N2at 400 and 800 °C. Then, the CO2uptake capacities were evaluated by dynamic breakthrough experiments in a temperature range of 40-100 °C and pressures up to 3 bar. The presented data were properly described by Langmuir model and it was revealed that the CMSW-S-800 sample, treated with sulfuric acid and activated at 800 °C, has the highest CO2uptake capacity with an amount adsorbed around 2.6 mol/kg at 40 °C. In the next step, a mathematical model has been developed to match the experimental dynamic breakthrough data and design a pressure swing adsorption (PSA) cyclic process to evaluate the capacity and potential of the best AC sample for CO2adsorption. The results arising from this work showed a possible route for the application of the compost as a source of activated carbon for the sorption of greenhouse gases.
- Local market structure in a hotelling townPublication . Pinto, Alberto A.; Almeida, João P.; Parreira, TelmoWe develop a theoretical framework to study the location-price competition in a Hotelling-type network game, extending the Hotelling model, with linear transportation costs, from a line (city) to a network (town). We show the existence of a pure Nash equilibrium price if, and only if, some ex- plicit conditions on the production costs and on the network structure hold. Furthermore, we prove that the local optimal localization of the firms are at the cross-roads of the town.
- Capture of CO2 in activated carbon synthesized from municipal solid waste compostPublication . Karimi, Mohsen; Zafanelli, Lucas F.A.S.; Almeida, João P.; Silva, José A.C.; Rodrigues, Alírio; Ströher, Gylles R.In this study, municipal solid waste composts obtained from mechanical biological treat-ment has been considered as a source of adsorbents for CO2 capture. Three samples de-rived from the maturated compost in the municipal solid wastes were modified to produce activated carbon. The first sample was treated with sulfuric acid, the second one was thermally treated at 800 0C and the last one was modified chemically and thermally with sulfuric acid and at 800 0C. Then, the CO2 uptake capacity of prepared samples was measured through breakthrough adsorption experiments at the post combustion operation-al conditions to collect isotherm data. Also a fixed bed adsorption mathematical model was developed by applying mass and energy balances. Results showed the municipal solid wastes have an excellent capacity to be considered as source of adsorbent for CO2 capture also the mathematical model is able to predict breakthrough data.
- The past lost train is the new futur!Publication . Ali, A.; Rodrigues, Carol; Antunes, Mateus Elias; Golebiewski, Stanislaw; Rocha, Vítor; Almeida, João P.; Sampaio, Jorge Humberto; Caseiro, RuiThe northeast region of Portugal named Trás-os-Montes is an historical province of Portugal, integrated in the Trás-os-Montes and Alto Douro region, where breathtaking landscapes made up of abounding vast plateaus, river valleys, mountains and castles. The people of Trás-os-Montes are authentic, hardworking and characterized by their honesty, tenacity and willingness to win, always ready to help others. Historically this region has always maintained its own identity, largely due to the fact that it is a region of difficult access. In this context of isolated region the train has always been the main vehicle for transporting not only people and goods, but also news and news that came from the rest of the country, particularly from the cities of Lisbon and Porto.
- Simulação computacional do contágio da gripe pessoa a pessoaPublication . Araújo, Ana Catarina Carneiro; Balsa, Carlos; Almeida, João P.Neste trabalho estuda-se a propagação do vírus da gripe numa comunidade escoar com 2000 pessoas recorrendo ao modelo matemático SIR em que se considera que a população está dividida em três grupos independentes: os Suscetíveis (S), os Infecciosos (l) e os Recuperados (R). 'O estudo è feito do" ponto" de"vista determinístico e estocástico.
- A co-cretion process for premium traditional portuguese pocket knifesPublication . Esteves, Tiago; Shcherbik, O.; Andrade, Karina Kelly; Borges, Juliane; Ali, S.; Almeida, João P.; Martins, AlbertoDuring an eight weeks DEMOLA project, from March to June 2019, a team of five students together with the representative of Martins Cutelaria Tradicional de Palaçoulo, putted into practice the steps towards an innovative design of a new premium series, the “Portuguese History Collection”. This design project was driven through a co-creation process with the traditional Portuguese pocket knifes company Martins Cutelaria Tradicional de Palaçoulo, based in the old village of Palaçoulo, Bragança, Portugal (see [1]). Martins Cutelaria, which has a long history in the design, production and innovation of traditional Portuguese pocket knifes, launched the challenge of designing a new premium line for their traditional pocket knifes segment. The challenge was to innovate while keeping untouched the identity, tradition and the solid values that are the pillars of the company since it was founded in 1954. Based on the company's motto: “Ter uma navalha Martins Palaçoulo, é ter nas mãos um pedaço da nossa história."(*) and inspired by the fact that the year 2019 celebrates the 500th anniversary of the departure of the navigator Fernão de Magalhães for his circumnavigation of the globe by sea, the team worked out the new pocket knifes collection “Portuguese History Collection – The Navigations”.
- Analysis of a bakery production system using discrete simulationPublication . Geraldes, Carla A.S.; Setti, Fabiane K.; Almeida, João P.The main objective of this study is to analyse different production scenarios of a company, and propose improvements with the use of discrete event simulation. We use a simulation tool, SIMIO software, to reproduce the existing production layout of the company. Our purpose is to gather relevant information about the actual production system behaviour, and to find strategies to increase the production level to meet the market demand. Based on initial simulation model, some production scenarios were developed involving the production of different products. The analysis of the developed models highlighted the need for improvements. Among the obtained results, the creation of different mixed production scenarios allowed to increase the production level while maintaining the current existing resources. The results of this work can be easily implemented in the company in order to increase the production level without increasing costs since they do not involve the purchase of new equipment. In conclusion, this study highlighted the ability of the simulation technique to analyse manufacturing processes throughout the creation of different scenarios providing insights on the production process improving the companies’ productive performance
- Anosov diffeomorphisms, renormalization and tilingsPublication . Almeida, João P.; Pinto, Alberto A.In this thesis, we prove a one-to-one correspondence between C^{1+} smooth conjugacy classes of circle diffeomorphisms that are C^{1+} fixed points of renormalization and C^{1+} conjugacy classes of Anosov diffeomorphisms whose Sinai-Ruelle-Bowen measure is absolutely continuous with respect to Lebesgue measure. Furthermore, we use ratio functions to parametrize the infinite dimensional space of C^{1+} smooth conjugacy classes of circle diffeomorphisms that are C^{1+} fixed points of renormalization. We introduce the notion of γ-tilings and we prove a one-to-one correspondence between (i) smooth conjugacy classes of Anosov diffeomorphisms, with an invariant measure absolutely continuous with respect to the Lebesgue measure, (ii) affine classes of γ-tilings and (iii) solenoid functions. The solenoid functions give a parametrization of the infinite dimensional space consisting of the mathematical objects described in the above equivalences.
- Operational Research IO2017, Valença, Portugal, June 28-30Publication . Vaz, A.I.; Almeida, João P.; Oliveira, José F.; Pinto, Alberto A.This proceedings book presents selected contributions from the XVIII Congress of APDIO (the Portuguese Association of Operational Research) held in Valença on June 28–30, 2017. Prepared by leading Portuguese and international researchers in the field of operations research, it covers a wide range of complex real-world applications of operations research methods using recent theoretical techniques, in order to narrow the gap between academic research and practical applications. Of particular interest are the applications of, nonlinear and mixed-integer programming, data envelopment analysis, clustering techniques, hybrid heuristics, supply chain management, and lot sizing and job scheduling problems. In most chapters, the problems, methods and methodologies described are complemented by supporting figures, tables and algorithms. The XVIII Congress of APDIO marked the 18th installment of the regular biannual meetings of APDIO – the Portuguese Association of Operational Research. The meetings bring together researchers, scholars and practitioners, as well as MSc and PhD students, working in the field of operations research to present and discuss their latest works. The main theme of the latest meeting was Operational Research Pro Bono. Given the breadth of topics covered, the book offers a valuable resource for all researchers, students and practitioners interested in the latest trends in this field.
- Operational research IO 2021—analytics for a better world. XXI Congress of APDIO, Figueira da Foz, Portugal, November 7–8, 2021Publication . Almeida, João P. (Ed.); Geraldes, Carla A.S. (Ed.); Lopes, Isabel Cristina (Ed.); Moniz, Samuel (Ed.); Oliveira, José F. (Ed.); Pinto, Alberto A. (Ed.)This book provides the current status of research on the application of OR methods to solve emerging and relevant operations management problems. Each chapter is a selected contribution of the IO2021 - XXI Congress of APDIO, the Portuguese Association of Operational Research, held in Figueira da Foz from 7 to 8 November 2021. Under the theme of analytics for a better world, the book presents interesting results and applications of OR cutting-edge methods and techniques to various real-world problems. Of particular importance are works applying nonlinear, multi-objective optimization, hybrid heuristics, multicriteria decision analysis, data envelopment analysis, simulation, clustering techniques and decision support systems, in different areas such as supply chain management, production planning and scheduling, logistics, energy, telecommunications, finance and health. All chapters were carefully reviewed by the members of the scientific program committee.