Search results for: Joana Filipa Pintéus Pereira
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 207

Search results for: Joana Filipa Pintéus Pereira

177 Consumption Habits of Low-Fat Plant Sterol-Enriched Yoghurt Enriched with Phytosterols

Authors: M. J. Reis Lima, J. Oliveira, A. C. Sousa Pereira, M. C. Castilho, E. Teixeira-Lemos

Abstract:

The increasing interest in plant sterol enriched foods is due to the fact that they reduce blood cholesterol concentrations without adverse side effects. In this context, enriched foods with phytosterols may be helpful in protecting population against atherosclerosis and cardiovascular diseases. The aim of the present work was to evaluate in a population of Viseu, Portugal, the consumption habits low-fat, plant sterol-enriched yoghurt. For this study, 577 inquiries were made and the sample was randomly selected for people shopping in various supermarkets. The preliminary results showed that the biggest consumers of these products were women aged 45 to 65 years old. Most of the people who claimed to buy these products consumed them once a day. Also, most of the consumers under antidyslipidemic therapeutics noticed positive effects on hypercholesterolemia.

Keywords: consumption habits, fermented milk, functional foods, low fat, phytosterols

Procedia PDF Downloads 430
176 A Step Towards Automating the Synthesis of a Scene Script

Authors: Americo Pereira, Ricardo Carvalho, Pedro Carvalho, Luis Corte-Real

Abstract:

Generating 3D content is a task mostly done by hand. It requires specific knowledge not only on how to use the tools for the task but also on the fundamentals of a 3D environment. In this work, we show that automatic generation of content can be achieved, from a scene script, by leveraging existing tools so that non-experts can easily engage in a 3D content generation without requiring vast amounts of time in exploring and learning how to use specific tools. This proposal carries several benefits, including flexible scene synthesis with different levels of detail. Our preliminary results show that the automatically generated content is comparable to the content generated by users with low experience in 3D modeling while vastly reducing the amount of time required for the generation and adds support to implement flexible scenarios for visual scene visualization.

Keywords: 3D virtualization, multimedia, scene script, synthesis

Procedia PDF Downloads 233
175 Proposal of Innovative Risk Assessment of Ergonomic Factors in the Production of Jet Engines Using AHP (Analytic Hierarchy Process)

Authors: Jose Cristiano Pereira, Gilson Brito Alves Lima

Abstract:

Ergonomics is a key factor affecting the operational safety and quality in the aircraft engine manufacturing industry and evidence shows that the lack of attention to it can increase the risk of accidents. In order to emphasize the importance of ergonomics, this paper systematically reviews the critical processes used in the aircraft engine production industry with focus on the ergonomic factors. about the subject to identify key ergonomic factors. Experts validated the factors and used AHP to rank the factors in order of significance. From the six key risk factors identified, the ones with the highest weight are psychological demand followed by understanding of operational side. These factors suggest that measures must be taken to improve ergonomic factors, quality and safety in the manufacturing of aircraft engines.

Keywords: ergonomics, safety, aviation, aircraft engine production

Procedia PDF Downloads 284
174 Development and Validation of the Response to Stressful Situations Scale in the General Population

Authors: Célia Barreto Carvalho, Carolina da Motta, Marina Sousa, Joana Cabral, Ana Luísa Carvalho, Ermelindo Peixoto

Abstract:

The aim of the current study was to develop and validate a Response to Stressful Situations Scale (RSSS) for the Portuguese population. This scale assesses the degree of stress experienced in scenarios that can constitute positive, negative and more neutral stressors, and also describes the physiological, emotional and behavioral reactions to those events according to their intensity. These scenario include typical stressor scenarios relevant to patients with schizophrenia, which are currently absent from most scale, assessing specific risks that these stressors may bring on subjects, which may prove useful in non-clinical and clinical populations (i.e. patients with mood or anxiety disorders, schizophrenia). Results from Principal Components Analysis and Confirmatory Factor Analysis of on two adult samples from general population allowed to confirm a three-factor model with good fit indices: χ2 (144)= 370.211, p = 0.000; GFI = 0.928; CFI = 0.927; TLI = 0.914, RMSEA = 0.055, P( rmsea ≤ 0.005) = 0.096; PCFI = 0.781. Further data analysis on the scale revealed that RSSS is an adequate assessment tool of stress response in adults to be used in further research and clinical settings, with good psychometric characteristics, adequate divergent and convergent validity, good temporal stability and high internal consistency.

Keywords: assessment, stress events, stress response, stress vulnerability

Procedia PDF Downloads 488
173 Chromium Adsorption by Modified Wood

Authors: I. Domingos, B. Esteves, A. Figueirinha, Luísa P. Cruz-Lopes, J. Ferreira, H. Pereira

Abstract:

Chromium is one of the most common heavy metals which exist in very high concentrations in wastewater. The removal is very expensive due to the high cost of normal adsorbents. Lignocellulosic materials and mainly treated materials have proven to be a good solution for this problem. Adsorption tests were performed at different pH, different times and with varying concentrations. Results show that is at pH 3 that treated wood absorbs more chromium ranging from 70% (2h treatment) to almost 100% (12 h treatment) much more than untreated wood with less than 40%. Most of the adsorption is made in the first 2-3 hours for untreated and heat treated wood. Modified wood adsorbs more chromium throughout the time. For all the samples, adsorption fitted relatively well the Langmuir model with correlation coefficient ranging from 0.85 to 0.97. The results show that heat treated wood is a good adsorbent ant that this might be a good utilization for sawdust from treating companies.

Keywords: adsorption, chromium, heat treatment, wood modification

Procedia PDF Downloads 461
172 Cerium Salt Effect in 70s Bioactive Glass

Authors: Alessandra N. Santos, Max P. Ferreira, Alexandra R. P. Silva, Agda A. R. de Oliveira, Marivalda M. Pereira

Abstract:

The literature describes experiments, in which ceria nanoparticles in the bioactive glass significantly improve differentiation of stem cells into osteoblasts and increase production of collagen. It is not known whether this effect observed due to the presence of nanoceria can be also observed in the presence of cerium in the bioactive glass network. The effect of cerium into bioactive glasses using the sol–gel route is the focus of this work, with the goal to develop a material for tissue engineering with the potential to enhance osteogenesis. A bioactive glass composition based on 70% SiO2–30% CaO is produced with the addition of cerium. The analyses XRD, FTIR, SEM/EDS, BET/BJH, in vitro bioactivity test and the Cell viability assay were performed. The results show that cerium remains in the bioactive glass structure. The obtained material present in vitro bioactivity and promote the cell viability.

Keywords: bioactive glass, bioactivity, cerium salt, material characterization, sol-gel method

Procedia PDF Downloads 199
171 The Effect of High-Pressure Processing on the Inactivation of Saccharomyces cerevisiae in Different Concentration of Manuka Honey and Its Relation with ° Brix

Authors: Noor Akhmazillah Fauzi, Mohammed Mehdi Farid, Filipa V. Silva

Abstract:

The aim of this paper is to investigate if different concentration of Manuka honey (as a model food) has a major influence on the inactivation of Saccharomyces cerevisiae (as the testing microorganism) after subjecting it to HPP. Honey samples with different sugar concentrations (20, 30, 40, 50, 60 and 70 °Brix) were prepared aseptically using sterilized distilled water. No dilution of honey was made for the 80 °Brix sample. For the 0 °Brix sample (control), sterilized distilled water was used. Thermal treatment at 55 °C for 10 min (conventionally applied in honey pasteurisation in industry) was carried out for comparison purpose. S. cerevisiae cell numbers in honey samples were established before and after each HPP and thermal treatment. The number of surviving cells was determined after a proper dilution of the untreated and treated samples by the viable plate count method. S. cerevisiae cells, in different honey concentrations (0 to 80 °Brix), subjected to 600 MPa (at ambient temperature) showed an increasing resistance to inactivation with °Brix. A significant correlation (p < 0.05) between cell reduction and °Brix was found. Cell reduction in high pressure-treated samples varied linearly with °Brix (R2 > 0.9), confirming that the baroprotective effect of the food is due to sugar content. This study has practical implications in establishing efficient process design for commercial manufacturing of high sugar food products and on the potential use of HPP for such products.

Keywords: high pressure processing, honey, Saccharomyces cerevisiae, °Brix

Procedia PDF Downloads 324
170 Models Development of Graphical Human Interface Using Fuzzy Logic

Authors: Érick Aragão Ribeiro, George André Pereira Thé, José Marques Soares

Abstract:

Graphical Human Interface, also known as supervision software, are increasingly present in industrial processes supported by Supervisory Control and Data Acquisition (SCADA) systems and so it is evident the need for qualified developers. In order to make engineering students able to produce high quality supervision software, method for the development must be created. In this paper we propose model, based on the international standards ISO/IEC 25010 and ISO/IEC 25040, for the development of graphical human interface. When compared with to other methods through experiments, the model here presented leads to improved quality indexes, therefore help guiding the decisions of programmers. Results show the efficiency of the models and the contribution to student learning. Students assessed the training they have received and considered it satisfactory.

Keywords: software development models, software quality, supervision software, fuzzy logic

Procedia PDF Downloads 348
169 Shiva's Dance: Crisis, Local Institutions, and Private Firms

Authors: João Pereira Dos Santos

Abstract:

The uneven spatial distribution of start-ups and their respective survival may reflect comparative advantages resulting from the local institutional background. For the first time, we explore this idea using Data Envelopment Analysis (DEA) to assess relative efficiency of Portuguese municipalities in this specific context. We depart from the related literature where expenditure is perceived as a desirable input by choosing a measure of fiscal responsibility and infrastructural variables in the first stage. Comparing results for 2006 and 2010, we find that mean performance decreased substantially with 1) the effects of the Global Financial Crisis; 2) as municipal population increases and 3) as financial independence decreases. A second stage is then computed employing a double-bootstrap procedure to evaluate how the regional context outside the control of local authorities (e.g. demographic characteristics and political preferences) impacts on efficiency.

Keywords: entrepreneurship, political economy, public finance, accountability, crisis, efficiency, Portuguese municipalities

Procedia PDF Downloads 472
168 Nonparametric Estimation of Risk-Neutral Densities via Empirical Esscher Transform

Authors: Manoel Pereira, Alvaro Veiga, Camila Epprecht, Renato Costa

Abstract:

This paper introduces an empirical version of the Esscher transform for risk-neutral option pricing. Traditional parametric methods require the formulation of an explicit risk-neutral model and are operational only for a few probability distributions for the returns of the underlying. In our proposal, we make only mild assumptions on the pricing kernel and there is no need for the formulation of the risk-neutral model for the returns. First, we simulate sample paths for the returns under the physical distribution. Then, based on the empirical Esscher transform, the sample is reweighted, giving rise to a risk-neutralized sample from which derivative prices can be obtained by a weighted sum of the options pay-offs in each path. We compare our proposal with some traditional parametric pricing methods in four experiments with artificial and real data.

Keywords: esscher transform, generalized autoregressive Conditional Heteroscedastic (GARCH), nonparametric option pricing

Procedia PDF Downloads 459
167 Ecological Networks: From Structural Analysis to Synchronization

Authors: N. F. F. Ebecken, G. C. Pereira

Abstract:

Ecological systems are exposed and are influenced by various natural and anthropogenic disturbances. They produce various effects and states seeking response symmetry to a state of global phase coherence or stability and balance of their food webs. This research project addresses the development of a computational methodology for modeling plankton food webs. The use of algorithms to establish connections, the generation of representative fuzzy multigraphs and application of technical analysis of complex networks provide a set of tools for defining, analyzing and evaluating community structure of coastal aquatic ecosystems, beyond the estimate of possible external impacts to the networks. Thus, this study aims to develop computational systems and data models to assess how these ecological networks are structurally and functionally organized, to analyze the types and degree of compartmentalization and synchronization between oscillatory and interconnected elements network and the influence of disturbances on the overall pattern of rhythmicity of the system.

Keywords: ecological networks, plankton food webs, fuzzy multigraphs, dynamic of networks

Procedia PDF Downloads 276
166 Anti-Angiogenic Effects of the Macrovipera lebetina obtusa Snake Crude Venom and Obtustatin

Authors: Narine Ghazaryan, Joana Catarina Macedo, Sara Vaz, Naira Ayvazyan, Elsa Logarinho

Abstract:

Macrovipera lebetina obtusa (MLO) is a poisonous snake in Armenia. Obtustatin represents the shortest known monomeric disintegrin, isolated from the snake venom of MLO, and is known to specifically inhibit α1β1 integrin. Its oncostatic effect is due to the inhibition of angiogenesis, which likely arises from α1β1 integrin inhibition in the endothelial cells. To explore the therapeutic potential of the MLO snake venom and obtustatin, we studied activity of obtustatin and MLO venom in vitro, by testing their efficacy in human dermal microvascular endothelial cells (HMVEC-D) and in vivo, using chick embryo chorioallantoic membrane assay (CAM assay). Our in vitro results showed that obtustatin in comparison with MLO venom did not exhibit cytotoxic activity in HMVEC-D cells in comparison to MLO venom. But in vivo results have shown that 4µg /embryo (90 µM) of obtustatin inhibited angiogenesis induced by FGF2 by 17% while MLO snake venom induced 22% reduction of the angiogenic index. The concentration of obtustatin in the crude MLO venom was 0.3 nM, which is 300.000 times less than the concentration of the obtustatin itself. Given this enormous difference in concentration, it is likely that some components of the crude venom contribute to the observed anti-angiogenic effect. Hypotheses will be ascertained to justify this action: components in the MLO venom may increase obtustatin efficacy or have independent but synergic anti-angiogenic activities.

Keywords: angiogenesis, alpa1 beta 1 integrin, Macrovipera lebetina obtusa, obtustatin

Procedia PDF Downloads 161
165 Sentiment Analysis on the East Timor Accession Process to the ASEAN

Authors: Marcelino Caetano Noronha, Vosco Pereira, Jose Soares Pinto, Ferdinando Da C. Saores

Abstract:

One particularly popular social media platform is Youtube. It’s a video-sharing platform where users can submit videos, and other users can like, dislike or comment on the videos. In this study, we conduct a binary classification task on YouTube’s video comments and review from the users regarding the accession process of Timor Leste to become the eleventh member of the Association of South East Asian Nations (ASEAN). We scrape the data directly from the public YouTube video and apply several pre-processing and weighting techniques. Before conducting the classification, we categorized the data into two classes, namely positive and negative. In the classification part, we apply Support Vector Machine (SVM) algorithm. By comparing with Naïve Bayes Algorithm, the experiment showed SVM achieved 84.1% of Accuracy, 94.5% of Precision, and Recall 73.8% simultaneously.

Keywords: classification, YouTube, sentiment analysis, support sector machine

Procedia PDF Downloads 67
164 Analysis of High-Velocity Impacts on Concrete

Authors: Conceição, J. F. M., Rebelo H., Corneliu C., Pereira L.

Abstract:

This research analyses the response of two distinct types of concrete blocks, each possessing an approximate unconfined compressive strength of 30MPa, when exposed to high-velocity impacts produced by an Explosively Formed Penetrator (EFP) traveling at an initial velocity of 1200 m/s. Given the scarcity of studies exploring high-velocity impacts on concrete, the primary aim of this research is to scrutinize how concrete behaves under high-speed impacts, ultimately contributing valuable insights to the development of protective structures. To achieve this objective, a comprehensive numerical analysis was carried out in LS-DYNA to delve into the fracture mechanisms inherent in concrete under such extreme conditions. Subsequently, the obtained numerical outcomes were compared and validated through eight experimental field tests. The methodology employed involved a robust combination of numerical simulations and real-world experiments, ensuring a comprehensive understanding of concrete behavior in scenarios involving rapid, high-energy impacts.

Keywords: high-velocity, impact, numerical analysis, experimental tests, concrete

Procedia PDF Downloads 46
163 Development of Drug Delivery Systems for Endoplasmic Reticulum Amino Peptidases Modulators Using Electrospinning

Authors: Filipa Vasconcelos

Abstract:

The administration of endoplasmic reticulum amino peptidases (ERAP1 or ERAP2) inhibitors can be used for therapeutic approaches against cancer and auto-immune diseases. However, one of the main shortcomings of drug delivery systems (DDS) is associated with the drug off-target distribution, which can lead to an increase in its side effects on the patient’s body. To overcome such limitations, the encapsulation of four representative compounds of ERAP inhibitors into Polycaprolactone (PCL), Polyvinyl-alcohol (PVA), crosslinked PVA, and PVA with nanoparticles (liposomes) electrospun fibrous meshes is proposed as a safe and controlled drug release system. The use of electrospun fibrous meshes as a DDS allows efficient solvent evaporation giving limited time to the encapsulated drug to recrystallize, continuous delivery of the drug while the fibers degrade, prevention of initial burst release (sustained release), tunable dosages, and the encapsulation of other agents. This is possible due to the fibers' small diameters and resemblance to the extracellular matrix (confirmed by scanning electron microscopy results), high specific surface area, and good mechanical strength/stability. Furthermore, release studies conducted on PCL, PVA, crosslinked PVA, and PVA with nanoparticles (liposomes) electrospun fibrous meshes with each of the ERAP compounds encapsulated demonstrated that they were capable of releasing >60%, 50%, 40%, and 45% of the total ERAP concentration, respectively. Fibrous meshes with ERAP_E compound encapsulated achieved higher released concentrations (75.65%, 62.41%, 56.05%, and 65.39%, respectively). Toxicity studies of fibrous meshes with encapsulated compounds are currently being accessed in vitro, as well as pharmacokinetics and dynamics studies. The last step includes the implantation of the drug-loaded fibrous meshes in vivo.

Keywords: drug delivery, electrospinning, ERAP inhibitors, liposomes

Procedia PDF Downloads 78
162 Making Sense of Cyber Pornography among Young Adult Couples

Authors: Marianne Lumacang, Jessarine Dultra, Joana Fenol

Abstract:

Filipinos are known to be conservative, sex or pornography is not discussed openly in the Philippines, topic of sex, when raised, will most likely elicit snickers, jokes, and blushes in most Filipino or expressions of disgust. However, a lot of Filipinos are still engaging into this kind of activity for some reasons. The study aims to determine young adult’s point of view about cyber pornography viewing, as well as their reasons for engagement, and its effects on them and their relationship with their partner. Interpretative Phenomenological Analysis was used to explore how young adults make sense of cyber pornography viewing. The study focused on Filipino young adults who are in a romantic or married relationship, engage in cyber pornography viewing, and currently residing in Cavite, Philippines. A total of four young adult couples, four females and four males participated in the study as research participants. Data gathered from a total of four young adult couples resulted to a total of nine superordinate themes focusing on (1) exploring young adult couple’s rationales for cyber pornography viewing, (2) experiences of positive effects in engaging to cyber pornography viewing, (3) experiences of negative effects in engaging to cyber pornography viewing, (4) experience of infidelity, (5) experience of necessity, (6) females perception about cyber pornography viewing towards self, (7) males perception about cyber pornography viewing towards self, (8) males perception about cyber pornography viewing towards romantic partner, and (9) males perception about cyber pornography viewing towards others.

Keywords: cyberpornography, Filipino, interpretative phenomenological analysis, making sense of cyberpornography, young adult

Procedia PDF Downloads 289
161 New Method to Increase Contrast of Electromicrograph of Rat Tissues Sections

Authors: Lise Paule Labéjof, Raíza Sales Pereira Bizerra, Galileu Barbosa Costa, Thaísa Barros dos Santos

Abstract:

Since the beginning of the microscopy, improving the image quality has always been a concern of its users. Especially for transmission electron microscopy (TEM), the problem is even more important due to the complexity of the sample preparation technique and the many variables that can affect the conservation of structures, proper operation of the equipment used and then the quality of the images obtained. Animal tissues being transparent it is necessary to apply a contrast agent in order to identify the elements of their ultrastructural morphology. Several methods of contrastation of tissues for TEM imaging have already been developed. The most used are the “in block” contrastation and “in situ” contrastation. This report presents an alternative technique of application of contrast agent in vivo, i.e. before sampling. By this new method the electromicrographies of the tissue sections have better contrast compared to that in situ and present no artefact of precipitation of contrast agent. Another advantage is that a small amount of contrast is needed to get a good result given that most of them are expensive and extremely toxic.

Keywords: image quality, microscopy research, staining technique, ultra thin section

Procedia PDF Downloads 402
160 An Approach for Multilayered Ecological Networks

Authors: N. F. F. Ebecken, G. C. Pereira

Abstract:

Although networks provide a powerful approach to the study of a wide variety of ecological systems, their formulation usually does not include various types of interactions, interactions that vary in space and time, and interconnected systems such as networks. The emerging field of 'multilayer networks' provides a natural framework for extending ecological systems analysis to include these multiple layers of complexity as it specifically allows for differentiation and modeling of intralayer and interlayer connectivity. The structure provides a set of concepts and tools that can be adapted and applied to the ecology, facilitating research in high dimensionality, heterogeneous systems in nature. Here, ecological multilayer networks are formally defined based on a review of prior and related approaches, illustrates their application and potential with existing data analyzes, and discusses limitations, challenges, and future applications. The integration of multilayer network theory into ecology offers a largely untapped potential to further address ecological complexity, to finally provide new theoretical and empirical insights into the architecture and dynamics of ecological systems.

Keywords: ecological networks, multilayered networks, sea ecology, Brazilian Coastal Area

Procedia PDF Downloads 117
159 Investigation of Polymer Composite for High Dose Dosimetry

Authors: Esther Lorrayne M. Pereira, Adriana S. M. Batista, Fabíola A. S. Ribeiro, Adelina P. Santos, Luiz O. Faria

Abstract:

In this work we have prepared nanocomposites made by mixing Poli (vinilidene fluoride) (PVDF), zirconium oxide (ZrO₂) and multi–walled carbon nanotubes (MWCNTs) aiming to find dosimetric properties for applications in high dose dosimetry. The samples were irradiated with a Co-60 source at constant dose rate (16.7 kGy/h), with doses ranging from 100 to 2750 kGy. The UV-Vis and FTIR spectrophotometry have been used to monitor the appearing of C=C conjugated bonds and radio-oxidation of carbon (C=O). FTIR spectrometry has that the absorbance intensities at 1715 cm⁻¹ and 1730 cm⁻¹ can be used for high dosimetry purposes for gamma doses ranging from 500 to 2750 kGy. In this range, it is possible to observe a linear relationship between Abs & Dose. Fading of signal was evaluated for one month and reproducibility in 2000 kGy dose. Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) was used for evaluated the dispersion ZrO₂ and MWCNT in the matrix of the PVDF.

Keywords: polymer, composite, high dose dosimetry, PVDF/ZrO₂/MWCNT

Procedia PDF Downloads 263
158 In vitro Bioacessibility of Phenolic Compounds from Fruit Spray Dried and Lyophilized Powder

Authors: Carolina Beres, Laurine Da Silva, Danielle Pereira, Ana Ribeiro, Renata Tonon, Caroline Mellinger-Silva, Karina Dos Santos, Flavia Gomes, Lourdes Cabral

Abstract:

The health benefits of bioactive compounds such as phenolics are well known. The main source of these compounds are fruits and derivates. This study had the objective to study the bioacessibility of phenolic compounds from grape pomace and juçara dried extracts. For this purpose both characterized extracts were submitted to a simulated human digestion and the total phenolic content, total anthocyanins and antioxidant scavenging capacity was determinate in digestive fractions (oral, gastric, intestinal and colonic). Juçara had a higher anthocianins bioacessibility (17.16%) when compared to grape pomace (2.08%). The opposite result was found for total phenolic compound, where the higher bioacessibility was for grape (400%). The phenolic compound increase indicates a more accessible compound in the human gut. The lyophilized process had a beneficial impact in the final accessibility of the phenolic compounds being a more promising technique.

Keywords: bioacessibility, phenolic compounds, grape, juçara

Procedia PDF Downloads 184
157 A Real Time Expert System for Decision Support in Nuclear Power Plants

Authors: Andressa dos Santos Nicolau, João P. da S.C Algusto, Claudio Márcio do N. A. Pereira, Roberto Schirru

Abstract:

In case of abnormal situations, the nuclear power plant (NPP) operators must follow written procedures to check the condition of the plant and to classify the type of emergency. In this paper, we proposed a Real Time Expert System in order to improve operator’s performance in case of transient or accident with reactor shutdown. The expert system’s knowledge is based on the sequence of events (SoE) of known accident and two emergency procedures of the Brazilian Pressurized Water Reactor (PWR) NPP and uses two kinds of knowledge representation: rule and logic trees. The results show that the system was able to classify the response of the automatic protection systems, as well as to evaluate the conditions of the plant, diagnosing the type of occurrence, recovery procedure to be followed, indicating the shutdown root cause, and classifying the emergency level.

Keywords: emergence procedure, expert system, operator support, PWR nuclear power plant

Procedia PDF Downloads 307
156 A New Family of Flying Wing Low Reynolds Number Airfoils

Authors: Ciro Sobrinho Campolina Martins, Halison da Silva Pereira, Vitor Mainenti Leal Lopes

Abstract:

Unmanned Aerial vehicles (UAVs) has been used in a wide range of applications, from precise agriculture monitoring for irrigation and fertilization to military attack missions. Long range performance is required for many of these applications. Tailless aircrafts are commonly used as long-range configurations and, due to its small amount of stability, the airfoil shape design of its wings plays a central role on the performance of the airplane. In this work, a new family of flying wing airfoils is designed for low Reynolds number flows, typical of small-middle UAVs. Camber, thickness and their maximum positions in the chord are variables used for the airfoil geometry optimization. Aerodynamic non-dimensional coefficients were obtained by the well-established Panel Method. High efficient airfoils with small pitch moment coefficient are obtained from the analysis described and its aerodynamic polars are plotted.

Keywords: airfoil design, flying wing, low Reynolds number, tailless aircraft, UAV

Procedia PDF Downloads 592
155 Designing a Model to Increase the Flow of Circular Economy Startups Using a Systemic and Multi-Generational Approach

Authors: Luís Marques, João Rocha, Andreia Fernandes, Maria Moura, Cláudia Caseiro, Filipa Figueiredo, João Nunes

Abstract:

The implementation of circularity strategies other than recycling, such as reducing the amount of raw material, as well as reusing or sharing existing products, remains marginal. The European Commission announced that the transition towards a more circular economy could lead to the net creation of about 700,000 jobs in Europe by 2030, through additional labour demand from recycling plants, repair services and other circular activities. Efforts to create new circular business models in accordance with completely circular processes, as opposed to linear ones, have increased considerably in recent years. In order to create a societal Circular Economy transition model, it is necessary to include innovative solutions, where startups play a key role. Early-stage startups based on new business models according to circular processes often face difficulties in creating enough impact. The StartUp Zero Program designs a model and approach to increase the flow of startups in the Circular Economy field, focusing on a systemic decision analysis and multi-generational approach, considering Multi-Criteria Decision Analysis to support a decision-making tool, which is also supported by the use of a combination of an Analytical Hierarchy Process and Multi-Attribute Value Theory methods. We define principles, criteria and indicators for evaluating startup prerogatives, quantifying the evaluation process in a unique result. Additionally, this entrepreneurship program spanning 16 months involved more than 2400 young people, from ages 14 to 23, in more than 200 interaction activities.

Keywords: circular economy, entrepreneurship, startups;, multi-criteria decision analysis

Procedia PDF Downloads 65
154 Effect of Gamma Irradiation on the Crystalline Structure of Poly(Vinylidene Fluoride)

Authors: Adriana Souza M. Batista, Cláubia Pereira, Luiz O. Faria

Abstract:

The irradiation of polymeric materials has received much attention because it can produce diverse changes in chemical structure and physical properties. Thus, studying the chemical and structural changes of polymers is important in practice to achieve optimal conditions for the modification of polymers. The effect of gamma irradiation on the crystalline structure of poly(vinylidene fluoride) (PVDF) has been investigated using differential scanning calorimetry (DSC) and X-ray diffraction techniques (XRD). Gamma irradiation was carried out in atmosphere air with doses between 100 kGy at 3,000 kGy with a Co-60 source. In the melting thermogram of the samples irradiated can be seen a bimodal melting endotherm is detected with two melting temperature. The lower melting temperature is attributed to melting of crystals originally present and the higher melting peak due to melting of crystals reorganized upon heat treatment. These results are consistent with those obtained by XRD technique showing increasing crystallinity with increasing irradiation dose, although the melting latent heat is decreasing.

Keywords: differential scanning calorimetry, gamma irradiation, PVDF, X-ray diffraction technique

Procedia PDF Downloads 372
153 Comparison of Classical Computer Vision vs. Convolutional Neural Networks Approaches for Weed Mapping in Aerial Images

Authors: Paulo Cesar Pereira Junior, Alexandre Monteiro, Rafael da Luz Ribeiro, Antonio Carlos Sobieranski, Aldo von Wangenheim

Abstract:

In this paper, we present a comparison between convolutional neural networks and classical computer vision approaches, for the specific precision agriculture problem of weed mapping on sugarcane fields aerial images. A systematic literature review was conducted to find which computer vision methods are being used on this specific problem. The most cited methods were implemented, as well as four models of convolutional neural networks. All implemented approaches were tested using the same dataset, and their results were quantitatively and qualitatively analyzed. The obtained results were compared to a human expert made ground truth for validation. The results indicate that the convolutional neural networks present better precision and generalize better than the classical models.

Keywords: convolutional neural networks, deep learning, digital image processing, precision agriculture, semantic segmentation, unmanned aerial vehicles

Procedia PDF Downloads 217
152 Narratives of the Body: Significance and Meanings of Tattoos of Selected Filipino LGBTs

Authors: Generoso Pamittan Jr., Freddielyn Pontemayor

Abstract:

Through the years, the purpose of tattoos in the Philippines, has changed from being tribal and traditional-ritualistic to personal and individualistic. Hence it is interesting to know the stories and meanings behind tattoos of particular individuals. Using the frames of Anabela Pereira’s concept of ‘body art’ as ‘visual language’, this paper scrutinizes the tattoos of selected Filipino LGBTs to (1) unfold the stories behind their body symbols, (2) describe the meanings and significance of their tattoos, and (3) determine the dominant themes that are common among the tattoos of the selected LGBTs. Semi-structured interviews were conducted with selected respondents to obtain in-depth information about the tattoos. Photos of tattoos were also taken, with respondents’ consent, to describe and analyze the details of tattoos’ patterns/ designs. Based on the interviews and analysis, most of the immediate relatives of the selected LGBTs were initially against the idea of having tattoos because of social stigma. However, the LGBT respondents considered their tattoos as symbols of their penchant for something (arts, cooking, etc.), expression of their personality and life’s aspirations, assertion of their identity amidst heteronormative tendencies and symbols that constantly remind them of the significant people and milestones in their lives.

Keywords: body art, body tattoo, gender, identity, LGBT, tattoo

Procedia PDF Downloads 153
151 Characterization of Gamma Irradiated PVDF and PVDF/Graphene Oxide Composites by Spectroscopic Techniques

Authors: Juliana V. Pereira, Adriana S. M. Batista, Jefferson P. Nascimento, Clascídia A. Furtado, Luiz O. Faria

Abstract:

The combination of the properties of graphene oxide (OG) and PVDF homopolymer makes their combined composite materials as multifunctional systems with great potential. Knowledge of the molecular structure is essential for better use. In this work, the degradation of PVDF polymer exposed to gamma irradiation in oxygen atmosphere in high dose rate has been studied and compared to degradation of PVDF/OG composites. The samples were irradiated with a Co-60 source at constant dose rate, with doses ranging from 100 kGy to 1,000 kGy. In FTIR data shown that the formation of oxidation products was at the both samples with formation of carbonyl and hydroxyl groups amongst the most prevalent products in the pure PVDF samples. In the other hand, the composites samples exhibit less presence of degradation products with predominant formation of carbonyl groups, these results also seen in the UV-Vis analysis. The results show that the samples of composites may have greater resistance to the irradiation process, since they have less degradation products than pure PVDF samples seen by spectroscopic techniques.

Keywords: gamma irradiation, PVDF, PVDF/OG composites, spectroscopic techniques

Procedia PDF Downloads 541
150 Homing of B Cells via Afferent Lymphatics

Authors: Sara Pereira-Nogueira, Tim Worbs, Marc Permanyer-Bosser, Reinhold Förster

Abstract:

While the entry mechanism of lymphocytes into the lymph node via the blood are well described, it is still largely unknown how cells enter lymph nodes that arrive via afferent lymphatics. In order to address this, our group has established a micro-injection technique in mice through which cells are delivered directly into the lymphatic vessel immediately afferent to the popliteal lymph node. Injected cells can then be tracked via multi-colour fluorescence or 2-photon microscopy, and their localization can be analysed within the popliteal or downstream lymph nodes by immunohistology. Since naïve B cells express the chemokine receptor CXCR5 we intra-lymphatically co-injected B cells derived from wildtype and Cxcr5-deficient mice. While CXCR5 does not play a role in guiding B cells out of the subcapsular sinus, it affects their positioning within the lymph node parenchyma, since CXCR5-deficient B cells are impaired in migrating into the B cell follicle. The knowledge obtained by studying B-cell migration may prove beneficial in clinical settings regarding tumor metastasis or autoimmune diseases.

Keywords: afferent lymphatics, B cell migration, chemokine, intra-lymphatic injection

Procedia PDF Downloads 235
149 Positive Parenting and Subjective Well-Being: Proposed Program for Parents of Gifted Children

Authors: Suzy Pereira, Alberto Rocha, Ana Almeida, Catarina Figueiredo, Helena Fonseca, Leonor Moreira, Carla Blum Vestena, Cristina Costa-Lobo

Abstract:

The socio-educational support to parents, through parental education intervention programs, is part of European social policies, aiming to respond to the needs of education, promotion of well-being and development of children and young people. The purpose of this research is to evaluate the impact of the Positive Parenting Program on the subjective well-being of the parents of gifted children. The Positive Parenting Program is authored and is conducted by the National Association of Study and Intervention in Giftedness, Portuguese Association. The central question to be explored in this research is: Does the promotion of positive parenting in parents of gifted children have a positive impact on the subjective well-being? The sample consisted of 30 parents, non-probabilistic sampling of convenience, of which 15 parents belong to the intervention group and the rest to the control group. One dimension will be evaluated - subjective well-being, through the PANAS questionnaire - before and after the sessions of this program. The aim is to contribute to the understanding of the process and results of the positive parenting program in parents of gifted children.

Keywords: positive parenting, subjective well-being, giftedness, parental education intervention programs

Procedia PDF Downloads 286
148 CFD Simulation and Experimental Validation of the Bubble-Induced Flow during Electrochemical Water Splitting

Authors: Gabriel Wosiak, Jeyse da Silva, Sthefany S. Sena, Renato N. de Andrade, Ernesto Pereira

Abstract:

The bubble formation during hydrogen production by electrolysis and several electrochemical processes is an inherent phenomenon and can impact the energy consumption of the processes. In this work, it was reported both experimental and computational results describe the effect of bubble displacement, which, under the cases investigated, leads to the formation of a convective flow in the solution. The process is self-sustained, and a solution vortex is formed, which modifies the bubble growth and covering at the electrode surface. Using the experimental data, we have built a model to simulate it, which, with high accuracy, describes the phenomena. Then, it simulated many different experimental conditions and evaluated the effects of the boundary conditions on the bubble surface covering the surface. We have observed a position-dependent bubble covering the surface, which has an effect on the water-splitting efficiency. It was shown that the bubble covering is not uniform at the electrode surface, and using statistical analysis; it was possible to evaluate the influence of the gas type (H2 and O2), current density, and the bubble size (and cross-effects) on the covering fraction and the asymmetric behavior over the electrode surface.

Keywords: water splitting, bubble, electrolysis, hydrogen production

Procedia PDF Downloads 67