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A prototype to enhance academic attendance using BLE beacons
No full textThis project addresses the prototyping and application of an attendance control solution in an academic context, using Beacons.
The introduction highlights the importance of effectively managing student attendance to ensure active participation in educational activities and provide insights into student engagement. BLE Beacons technology is compared to other RF signaling technologies, highlighting its advantages in terms of range, power consumption, cost, frequency, and data rate. BLE Beacon is chosen as the preferred technology due to its combination of adequate range, low power consumption, affordable cost, compatibility, security, and flexibility. The results section presents Estimote Beacons as devices used, highlighting their advanced features and techniques used, such as proximity and triangulation, to determine student presence. A visual summary of the project is presented in a flowchart that illustrates the operating processes of each stage. This solution promises to significantly improve the efficiency, safety, and quality of the academic environment, while simplifying the attendance recording process and providing valuable insights into student behavior.This work was supported by national funds through FCT/MCTES
(PIDDAC): CeDRI, UIDB/05757/2020 (DOI: 10.54499/UIDB/05757/2020)
and UIDP/05757/2020 (DOI: 10.54499/UIDP/05757/2020); and SusTEC,
LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020)
2nd. International Workshop on Additive Manufacturing and Sustainability (IWAM): book of proceedings
No full textIn recent years, the manufacturing processes have undergone a profound transformation, driven by the rapid evolution of additive manufacturing (AM) technologies. What began as a tool primarily for prototyping through stereolithography has now expanded into a versatile and innovative field capable of producing functional, end-use components across a wide range of industries. From fused deposition modeling (FDM) to selective laser melting (SLM) and beyond, AM has unlocked new possibilities in design, material utilization, and production efficiency. Today, additive manufacturing encompasses an extensive array of materials, including metals, polymers, paper, and even biological tissues, enabling applications that span from the mechanical industry to the biomedical sector.
One of the most compelling aspects of additive manufacturing is its potential to drive sustainability in modern production processes. Unlike traditional subtractive methods, which often generate significant material waste, AM builds components layer by layer, minimizing excess material and promoting resource efficiency. Furthermore, the ability to use eco-friendly and recyclable materials aligns with global efforts to reduce environmental impact. AM also supports the production of complex, customized parts on demand, reducing the need for large inventories and long-distance transportation, thereby lowering carbon emissions. By optimizing resource use and enabling more efficient production cycles, additive manufacturing is emerging as a cornerstone of sustainable manufacturing practices.
This proceeding book arrests the latest advancements, challenges, and opportunities in the field of additive manufacturing, with a particular focus on its transformative potential and contributions to sustainability. The works presented here reflect the interdisciplinary nature of AM, showcasing innovative techniques, materials, and applications that are shaping the future of manufacturing. From cutting-edge research to real-world case studies, this collection aims to inspire further exploration and collaboration, driving the adoption of additive manufacturing as a key enabler of sustainable industrial progress. We invite readers to probe into these pages and discover how AM is not only redefining manufacturing but also paving the way for a more sustainable and efficient future.info:eu-repo/semantics/publishedVersio
From experimental implementation to validation of natural-based electrospun solutions
No full textMestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáElectrospinning is a straightforward and versatile technology for producing fibers with diameters ranging from a few micrometers to hundredths of nanometers. It applies a strong electric field to charge a polymer solution contained within a syringe. This study focused on the assembly, implementation, and validation of an electrospinning equipment. Also, it was validated by testing a conventional synthetic polymer, polyethylene-oxide (PEO). Finally, mats using chitosan (CS) and hyaluronic acid (HA) as natural polymers were prepared with PEO used as a co-spinner. Solutions comprising various proportions of PEO/CS (40/60, 50/50, 60/40, and 70/30) and PEO/CS/HA (HA 0.1, 0.2, and 0.3%) exhibited the highest conductivity values (between 1306 and 1885 μS/cm) using acetic acid (AA) (50% w/w). The electrospun mats from these blends displayed superior uniformity compared to other films, with mean diameters ranging from 0.204 ± 0.046 μm to 0.282 ± 0.064 μm. Increasing the applied voltage in neat PEO solutions led to a decrease in fiber diameter from 0.540 ± 0.172 μm (10 kV film) to 0.362 ± 0.130 μm (16 kV film). However, all neat PEO electrospun mats showed beads and non-uniformities, mainly due to the presence of distilled water (DW) as a solvent. DW also
increased viscosity and reduced conductivity in PEO/HA blends compared to AA equivalents. PEO/HA (DW) solutions formed films of particles instead of fibers. PEO/HA (AA) mats exhibited average fiber diameters ranging from 0.311 ± 0.071 μm to 0.381 ± 0.094 μm, with lower levels of uniformity. All produced mats exhibited a high hydrophilicity, with PEO/CS mats demonstrating the highest contact angle (31° after 60 seconds; PEO/CS_30/70_AA). The addition of HA in PEO/CS_50/50_AA increased hydrophilicity. Interestingly, in the PEO/CS/HA mats, higher HA concentrations led to increased contact angles (18.10°, 22.50°, and 24.57° for 0.1%, 0.2%, and 0.3% HA, respectively), suggesting the formation of polyelectrolyte complexes between NH3+ (CS) and COO− (HA). The MTT assay results show no cytotoxicity in the PEO/CS and PEO/CS/HA electrospun mats. Cell viability for groups exposed to these mats exceeded 74.23%, highlighting the inherent biocompatibility of CS and HA. Overall, this study underscores the potential of CS and HA nanofibers for biomedical applications, alongside the successful implementation of the equipment.A tecnologia de eletrofiação oferece um método direto e versátil para produzir fibras com diâmetros variando de micrômetros a centésimos de nanômetros. A tecnologia opera aplicando um forte campo elétrico para carregar uma solução polimérica contida numa seringa com agulha. Este estudo focou-se na montagem, implementação e validação de um equipamento de eletrofiação. A sua validação foi alcançada usando diversas soluções compostas por quitosana (CS) e ácido hialuronico (HA) como polímeros naturais, combinadas com óxido de polietilieno (PEO) como co-fiador. Soluções contendo diferentes proporções de PEO/CS (40/60, 50/50, 60/40 e 70/30) e PEO/CS/HA (HA 0,1, 0,2 e 0,3%) resultaram nos maiores valores de
condutividade (entre 1306 e 1885 μS/cm) com ácido acético (AA) (50% m/m). As nanofibras dessas soluções exibiram uniformidade, comparativamente com outros filmes e apresentaram diâmetros médios de 0,204 ± 0,046 μm a 0,282 ± 0,064 μm. O aumento da voltagem aplicada nas soluções de PEO puras resultou numa diminuição do diâmetro da fibra de 0,540 ± 0,172 μm (filme 10 kV) para 0,362 ± 0,130 μm (filme 16 kV). Todos os filmes eletrofiados de PEO puro apresentaram grânulos e não uniformidades, principalmente devido ao uso de água destilada (DW) como solvente. A DW aumentou a viscosidade e reduziu a condutividade em misturas de PEO/HA em comparação com os equivalentes de AA. As soluções de PEO/HA
(DW) formaram filmes de partículas em vez de fibras. As nanofibras de PEO/HA (AA) exibiram diâmetros médios variando de 0,311 ± 0,071 μm a 0,381 ± 0,094 μm, com níveis inferiores de uniformidade. Todos os filmes exibiram elevada hidrofílicidade, com as nanofibras de PEO/CS originando o maior ângulo (31° após 60 segundos; PEO/CS_30/70_AA). A adição de HA na PEO/CS_50/50_AA aumentou a hidrofilicidade do filme. Nos filmes de PEO/CS/HA, concentrações superiores de HA levaram a aumentos do ângulo de contato
(18,10°, 22,50° e 24,57° para 0,1%, 0,2% e 0,3% de HA, respectivamente), sugerindo a formação de complexos polieletrólitos entre NH3+ (CS) e COO− (HA). Os resultados do ensaio MTT não mostram citotoxicidade para os filmes de PEO/CS e PEO/CS/HA. A viabilidade celular para os grupos expostos a esses filmes superou 74,23%, destacando a biocompatibilidade inerente de CS e HA. No geral, este estudo destaca o potencial das nanofibras de CS e HA para aplicações biomédicas, juntamente com a implementação bem-sucedida do equipamento
An Over-Actuated Hexacopter Tilt-Rotor UAV Prototype for Agriculture of Precision: Modeling and Control
Get PDFThis paper focuses on the modeling, control, and simulation of an over-actuated
hexacopter tilt-rotor (HTR). This configuration implies that two of the six actuators are
independently tilted using servomotors, which provide high maneuverability and reliability.
This approach is predicted to maintain zero pitch throughout the trajectory and is expected
to improve the aircraft’s steering accuracy. This arrangement is particularly beneficial for
precision agriculture (PA) applications where accurate monitoring and management of
crops are critical. The enhanced maneuverability allows for precise navigation in complex
vineyard environments, enabling the unmanned aerial vehicle (UAV) to perform tasks
such as aerial imaging and crop health monitoring. The employed control architecture
consists of cascaded proportional (P)-proportional, integral and derivative (PID) controllers
using the successive loop closure (SLC) method on the five controlled degrees of freedom
(DoFs). Simulated results using Gazebo demonstrate that the HTR achieves stability and
maneuverability throughout the flight path, significantly improving precision agriculture
practices. Furthermore, a comparison of the HTR with a traditional hexacopter validates
the proposed approach.This work was funded by national funds through FCT/MCTES (PIDDAC): CeDRI,
UIDB/05757/2020 (DOI: 10.54499/UIDB/05757/2020) and UIDP/05757/2020 (DOI: 10.54499/UIDP/
05757/2020); SusTEC, LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020); and the National Council
for Scientific and Technological Development—CNPq, related to project 442696/2023-0.info:eu-repo/semantics/publishedVersio
Enhancing classroom dynamics: exploring the synergy of social marketing, neuromarketing, and artificial intelligence
No full textAs a part of a research project, this paper refers to the assessment of the degree of knowledge integrating Social Marketing, Neuromarketing and Artificial Intelligence for sustainable economic development activities in Portugal. In addition, aiming to promote good behaviors and understand better the influence of Artificial Intelligence such as AI, VR, AR, big data, etc., on communications, social marketing can also explore neurometrics, biometrics and psychometrics factors to help individuals on their decision-making process. Furthermore, segmentation is a marketing technique that can be used to influence the decision-making process, even promoting good behavior.
Considering the assumption that good behavior is very important because it results in benefits not only the individual but also society and the environment, to promote these behaviors, social marketing must communicate through assertive messages. Using neuromarketing theoretical framework to support social marketing communications and understand better the decision-making process, this literature review presents a model which can help teachers as well as social marketeers to promote sports activities in higher education institutions.info:eu-repo/semantics/publishedVersio
Production of nondairy fermented products with chestnut puree as substrate and milk kefir grains or two lactic acid bacteria
No full textThis work aimed to study the production, for the first time, of three fermented
products of chestnut puree (CP) withmilk kefir grains, a higher nisin-producing
(Lactococcus (L.) lactis CECT 539) and a higher lactic acid-producing (Lactobacillus
(Lb.) casei CECT 4043) lactic acid bacteria (LAB). After studying the CP
rheology, the ability of the two LAB to assimilate the carbon sources (starch,
sucrose, glucose, and fructose) present in the CP was assayed. The two LAB
grew well on glucose, fructose, and sucrose, but they did not use starch. Fermentation
of CP with the two LAB and kefir grains allowed us to obtain three
fermented products that contained no alcohol and low levels of sugars, lactic,
and acetic acids, as well as viable cell counts. After 24 h of fermentation, bacterial
counts increased by 2.12 log10 cycles for Lb. casei and 2.44 log10 cycles for L.
lactis. Although the final counts for both LAB were very similar (p > 0.05), L. lactis
grew faster than Lb. casei and produced a higher concentration of lactic acid.
The total microbial counts for kefir increased by 1.16 log10 cycles, after 28 h of
incubation, indicating that the microorganisms of the kefir grains adapted well
to the composition of the CP. As no ethanol was detected, these results suggest
the possibility of producing healthy, nonalcoholic, and low-calorie CPs.This research was funded by Foundation for Science
and Technology (FCT, Portugal). The authors are
grateful for the financial support by national funds
FCT/MCTES to CIMO, UIDB/00690/2020 (DOI:
10.54499/UIDB/00690/2020) and UIDP/00690/2020
(DOI: 10.54499/UIDP/00690/2020); and SusTEC,
LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020).
This work was also carried out within the Network of
Higher Education Institutions for the Safeguarding of the
MediterraneanDiet (RIESDM). Pablo G. del Río would like
to express gratitude to Consellería de Cultura, Educación,
Formación Profesional and Universidades da “Xunta de
Galicia” for his postdoctoral grant (ED481B-2022-020).info:eu-repo/semantics/publishedVersio
Looking for the optimal harvest time of red grapes with an enzymatic electrochemical multisensory system
No full textThe timing of the grape harvest is a critical decision for winemakers, as it greatly impacts the quality and
organoleptic characteristics of the resulting red wines. One key indicator for determining the optimal harvest
time is the phenolic content of the grapes. As the berries ripen, phenolic compounds in the grape skin cells
migrate from the seeds to the pulp and finally to the skin. However, monitoring these phenolic changes,
particularly in the seeds, presents a challenge. This research addresses this problem by developing a novel
technique to track the phenolic composition of seeds during ripening. The objective is to provide a reliable
method for winemakers to monitor the phenolic evolution and improve harvest decision-making.
In this study, a multisensory system consisting of four electrochemical enzymatic carbon paste sensors,
modified with tyrosinase and electrocatalytic materials (AuNPs, lutetium phthalocyanine, and nickel oxide
nanoparticles), was employed to analyze the phenolic content in grape seed extracts. The system monitored
weekly changes in the phenolic composition of the seeds from three red grape varieties—Cabernet Sauvignon,
Tempranillo, and Prieto Picudo—during their ripening from veraison to being overripe. Using voltammetric
techniques, the electrochemical responses were characterized by shifts in peak positions and intensity changes,
reflecting the oxidation/reduction of phenols. Principal Component Analysis (PCA) demonstrated the ability of
the array of sensors to discriminate phenolic changes across ripening stages, while Partial Least Squares (PLS)
regression provided robust correlation models between the electrochemical responses and seed phenolic content,
with correlation coefficients ranging from 0.93 to 0.99. The developed methodology successfully tracked
phenolic changes, offering a promising tool for monitoring grape seed maturation and assisting in determining
the optimal harvest time.We are grateful for the MINECO-FEDER Plan Nacional’s (PID2021-122365OB-100) financial assistance. Junta de Castilla y Leon- FEDER
VA202P20. BIOECOUVA-CLU-2019-04 and «Infraestructuras Red de Castilla y Léon (INFRARED) » UVA01. Interreg programme Espana-
Portugal (POCTEP) grant: 0039_MINORSENS_2_E.info:eu-repo/semantics/publishedVersio
Stock-term market impact of major cyber-attacks: evidence for the ten most exposed insurance firms to cyber risk
No full textThe main focus of this paper is to study empirically the impact of major cyberattacks in the
market value of the ten most exposed insurers to cyber risk. Using an event study for 53 global
cyberattacks, we observe a negative and statistically significant stock price reaction for insurers
around the cyberattack disclosure dates. The increase in the assessed probability of an increase in
future payments tends to prevail over the increase in demand and/or premiums caused by the
disclosure of global major cyberattacks. The results of our analysis also show a higher negative
stock market reaction for small insurers and when involves financial information loss.This paper is financed by Portuguese national funds through FCT – Fundação para a Ciência e a Tecnologia, I.P., projects numbers UIDB/00685/2020 (António Martins) and UNIAG, UIDB/04752/2020 and UIDP/04752/2020 (Nuno Moutinho).info:eu-repo/semantics/publishedVersio
Dual-stage vacuum pressure swing adsorption for green hydrogen recovery from natural gas grids
No full textPurification of green hydrogen (GH) from natural gas grids (NGG) can be expensive and challenging through a single-step Pressure Swing Adsorption (PSA) process due to the low H2 concentration in the grid (99 % v/v). A mathematical model is developed in Aspen adsorption, where numerical simulations are performed to establish the best operating conditions of the global DS-VPSA. A parametric study is also conducted to optimize performance parameters such as recovery, purity, productivity, and specific energy. The results indicate that it is possible to achieve a final H2 product with a purity of 99.97 % (fuel cell grade), a recovery of 67 %, and productivity of 1.60x10-2 kgH2/kgads/hr, and a total specific energy consumption of 10.06 MJ/kgH2, which is a significant achievement reported so far.The authors are grateful to the Foundation for Science and Tech-
nology (FCT, Portugal) for financial support: (1) under project PTDC/EQU-EPQ/0467/2020 (DOI: 10.54499/PTDC/EQU-EPQ/0467/2020), (2) through the national funds FCT/MCTES (PIDDAC): CIMO, UIDB/00690/2020 (DOI: 10.54499/UIDB/00690/2020) and UIDP/00690/2020 (DOI: 10.54499/UIDP/00690/2020); and SusTEC, LA/P/0007/2020 (DOI:10.54499/LA/P/0007/2020), (3) by the national funds
through FCT/MCTES (PIDDAC): LSRE-LCM, UIDB/50020/2020 (DOI: 10.54499/UIDB/50020/2020) and UIDP/50020/2020 (DOI: 10.54499/UIDP/50020/2020); and ALiCE, LA/P/0045/2020 (DOI: 10.54499/LA/
P/0045/2020). Additionally, we thank national funding from the FCT
Foundation for Science and Technology through the individual research
grant 2020.07925.BD (DOI: 10.54499/2020.07925.BD) of Lucas F. A. S.
Zafanelli.info:eu-repo/semantics/publishedVersio
Cycling and Running are More Predictive of Overall Race Finish Time than Swimming in IRONMAN® Age Group Triathletes
Get PDFSeveral studies have evaluated the most predictive discipline (swimming, cycling, and running) of performance in elite IRONMAN® triathletes. However, no study has ever determined the most decisive discipline for IRONMAN® age group triathletes. The present study analyzed the importance of the three disciplines on the overall race times in IRONMAN® age group triathletes, in order to try and determine the most predictive discipline in IRONMAN® for age group triathletes, and whether the importance of the split disciplines changes with increasing age.
This cross-sectional study used 687,696 IRONMAN® age group triathletes race records (553,608 from males and 134,088 from females). Age group athletes were divided in 5-year age groups (i.e., 18–24, 25–29, 30–34,…,70–74, and last 75 + years). The relationships between split disciplines (i.e., swimming, cycling, and running) and overall race times were evaluated using Spearman and Pearson correlations. A multi-linear regression model was used to calculate their prediction strength.
The overall finish time correlated more with cycling and running times than with swimming times for both male and female IRONMAN® age group triathletes (r = 0.88 and r = 0.89 for females; r = 0.89 and r = 0.90 for males, respectively). All correlation coefficients decreased with increasing age, which was more noticeable for the swimming discipline.
Both cycling and running are more predictive than swimming in IRONMAN® age group triathletes, where the correlation between the overall race times and the split times decreased with increasing age more in swimming than in cycling and running. These insights are useful for IRONMAN® age group triathletes and their coaches in planning their IRONMAN® race preparation and concentrating training on the more predictive disciplines