Search results for: Davide Silva
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 428

Search results for: Davide Silva

428 RF Propagation Analysis in Outdoor Environments Using RSSI Measurements Applied in ZigBee Sensor Networks

Authors: Teles de Sales Bezerra, Saulo Aislan da Silva Eleuterio, José Anderson Rodrigues de Souza, Jeronimo Silva Rocha

Abstract:

Propagation in radio frequency is a constant concern in the application of Wireless Sensor Networks (WSN), the behavior of an environment determines how good the quality of signal reception. The objective of this paper is to analyze the behavior of a WSN in an environment for agriculture where environmental variables are present and correlate the capture of values received signal strength (RSSI) with a propagation model.

Keywords: propagation, WSN, agriculture, quality

Procedia PDF Downloads 714
427 A Proposal of Ontology about Brazilian Government Transparency Portal

Authors: Estela Mayra de Moura Vianna, Thiago José Tavares Ávila, Bruno Morais Silva, Diego Henrique Bezerra, Paulo Henrique Gomes Silva, Alan Pedro da Silva

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The Brazilian Federal Constitution defines the access to information as a crucial right of the citizen and the Law on Access to Public Information, which regulates this right. Accordingly, the Fiscal Responsibility Act, 2000, amended in 2009 by the “Law of Transparency”, began demanding a wider disclosure of public accounts for the society, including electronic media for public access. Thus, public entities began to create "Transparency Portals," which aim to gather a diversity of data and information. However, this information, in general, is still published in formats that do not simplify understanding of the data by citizens and that could be better especially available for audit purposes. In this context, a proposal of ontology about Brazilian Transparency Portal can play a key role in how these data will be better available. This study aims to identify and implement in ontology, the data model about Transparency Portal ecosystem, with emphasis in activities that use these data for some applications, like audits, press activities, social government control, and others.

Keywords: audit, government transparency, ontology, public sector

Procedia PDF Downloads 463
426 The Regulation on Human Exposure to Electromagnetic Fields for Brazilian Power System

Authors: Hugo Manoel Olivera Da Silva, Ricardo Silva Thé Pontes

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In this work, is presented an analysis of the Brazilian regulation on human exposure to electromagnetic fields, which provides limits to electric fields, magnetic and electromagnetic fields. The regulations for the electricity sector was in charge of the Agência Nacional de Energia Elétrica-ANEEL, the Brazilian Electricity Regulatory Agency, that made it through the Normative Resolution Nº 398/2010, resulting in a series of obligations for the agents of the electricity sector, especially in the areas of generation, transmission, and distribution.

Keywords: adverse effects, electric energy, electric and magnetic fields, human health, regulation

Procedia PDF Downloads 565
425 Automation of Kitchen Chemical in the Textile Industry

Authors: José Luiz da Silva Neto, Renato Sipelli Silva, Érick Aragão Ribeiro

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The automation of industrial processes plays a vital role in industries today, becoming an integral and important part of the industrial process and modern production. The process control systems are designed to maximize production, reduce costs and minimize risks in production. However, these systems are generally not deployed methodologies and planning. So that this article describes the development of an automation system of a kitchen preparation of chemicals in the textile industry based on a retrofitting methodology that provides more quality into the process at a lower cost.

Keywords: automation, textile industry, kitchen chemical, information integration

Procedia PDF Downloads 388
424 Effect of Ultrasound on the Hydrolysis of Soy Oil Catalyzed by 1,3-Specific Lipase Abstract

Authors: Jamal Abd Awadallak, Thiago Olinek Reinehr, Eduardo Raizer, Deise Molinari, Edson Antonio, Camila da Silva da Silva

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The hydrolysis of soy oil catalyzed by 1,3-specific enzyme (Lecitase Ultra) in a well-stirred bioreactor was studied. Two forms of applications of the ultrasound were evaluated aiming to increase reaction rates, wherein the use of probe ultrasound associated with the use of surfactant to pre-emulsify the substrate showed the best results. Two different reaction periods were found: the first where the ultrasound has great influence on reaction rates, and the second where ultrasound influence is minimal. Studies on the time of pre-emulsification, surfactant concentration and enzyme concentration showed that the initial rate of hydrolysis depends on the interfacial area between the oil phase and the aqueous phase containing the enzyme.

Keywords: specific enzyme, free fatty acids, Hydrolysis, lecitase ultra, ultrasound

Procedia PDF Downloads 535
423 Energy Efficient Heterogeneous System for Wireless Sensor Networks (WSN)

Authors: José Anderson Rodrigues de Souza, Teles de Sales Bezerra, Saulo Aislan da Silva Eleuterio, Jeronimo Silva Rocha

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Mobile devices are increasingly occupying sectors of society and one of its most important features is mobility. However, the use of mobile devices is subject to the lifetime of the batteries. Thus, the use of energy batteries has become an important issue in the study of wireless network technologies. In this context, new solutions that enable aggregate energy efficiency not only through energy saving, and principally they are evaluated from a more realistic model of energy discharge, if easy adaptation to existing protocols. This paper presents a study on the energy needed and the lifetime for Wireless Sensor Networks (WSN) using a heterogeneous network and applying the LEACH protocol.

Keywords: wireless sensor networks, energy efficiency, heterogeneous, LEACH protocol

Procedia PDF Downloads 538
422 Human Resources Management Practices in Hospitality Companies

Authors: Dora Martins, Susana Silva, Cândida Silva

Abstract:

Human Resources Management (HRM) has been recognized by academics and practitioners as an important element in organizations. Therefore, this paper explores the best practices of HRM and seeks to understand the level of participation in the development of these practices by human resources managers in the hospitality industry and compare it with other industries. Thus, the study compared the HRM practices of companies in the hospitality sector with HRM practices of companies in other sectors, and identifies the main differences between their HRM practices. The results show that the most frequent HRM practices in all companies, independently of its sector of activity, are hiring and training. When comparing hospitality sector with other sectors of activity, some differences were noticed, namely in the adoption of the practices of communication and information sharing, and of recruitment and selection. According to these results, the paper discusses the major theoretical and practical implications. Suggestions for future research are also presented.

Keywords: exploratory study, human resources management practices, human resources manager, hospitality companies, Portuguese companies

Procedia PDF Downloads 446
421 Portuguese Influence on Minas Gerais Dessert Culinary During Brazil Colonization Period

Authors: Silvania M. P. Silva, Ricardo A. Mazaro, Gemilde M. Queiroz, Josefa Barbosa, Lucas S. Victorino, Grasiela J. Silva

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The Minas Gerais sweets have a remarkable personality, perceived on the original usage of fruits, sweets, and cheeses in the Brazilian gastronomic landscape, as a unique representation of Minas Gerais. This memory-related and feeling-oriented food is one of the treasures common to all Brazilians. It is mandatory to mention its Portuguese roots for the use of honey, as well as sugar cane and its countless possibilities. This work will show that this heritage is predominantly Portuguese, born in Portuguese convents and that it crossed the Atlantic. Through a historical survey, visits to mining towns known for their sweet culture and material collected in these places, we present the protagonists of this journey of flavors: the Portuguese cake makers (boleiras), who brought the knowledge, ingredients, and the dream of a better life in the crowded mines of gold and opportunities, helping to form a new Minas Gerais knowledge with their delicacies.

Keywords: sweets from portugal, convent sweets, minas gerais, brazil

Procedia PDF Downloads 119
420 Vieira Da Silva's Tiles at Universidade Federal Rural Do Rio de Janeiro: A Conservation and Restoration Project

Authors: Adriana Anselmo Oliveira

Abstract:

The present project showcases a tile work from the Franco-Portuguese artist Maria Helena Vieira da Silva (1908-1992). It is a set of 8 panels composed of figurative and geometric tiles, with extra tiles framing nearby doors and windows in a study room in the (UFRRJ, Universidade Federal Rural do Rio de Janeiro). The aforementioned work was created between 1942 and 1943, during the artist's 6 year exile in the Brazilian city. This one-of-a-kind tileset was designed and made by Vieira da Silva between 1942 and 1943. Over the years, several units were lost, which led to their replacement in the nineties. However, these replacements don't do justice to the original work of art. In 2007, a project was initiated to fully repair and maintain the set. Three panels are removed and restored, but the project is halted. To this day, the three fully restored panels remain in boxes. In 2016 a new restoration project is submitted by the (Faculdade de Belas Artes da Universidade de Lisboa) in collaboration with de (Fundacão Árpád Szenes-Vieira da Silva). There are many varied opinions on restoring and conserving older pieces of art, however, we have the moral duty to safeguard the original materials used by the artist along with the artists original vision and also to care for the future generations of students who will use the space in which the tile-work was inserted. Many tiles have been replaced by white tiles, tiles with a divergent colour pallet and technique, and in a few cases, the incorrect place or way around. These many factors make it increasingly difficult to maintain the artists original vision and destroy and chance of coherence within the artwork itself. The conservative technician cannot make new images to fill the empty spaces or mark the remaining images with their own creative input. with reliable photographic documentation that can provide us with the necessary vision to allow us to proceed with an accurate reconstruction, we have the obligation to proceed and return the piece of art to its true form, as in its current state, it is impossible to maintain its original glory. Using the information we have, we must find a way to differentiate the original tiles from the reconstructions in order to recreate and reclaim the original message from the artist. The objective of this project is to understand the significance of tiles in Vieira da Silva's art as well as the influence they had on the artist's pictorial language since the colour definition on tile work is vastly different from the painting process as the materials change during their merger. Another primary goal is to understand what the previous interventions achieved besides increasing the artworks durability. The main objective is to submit a proposal that can salvage the artist's visual intention and supports it for posteriority. In summary, this proposal goes further than the usual conservative interventions as it intends to recreate the original artistic worth, prioritising the aesthetics and keeping its soul alive.

Keywords: Vieira da Silva, tiles, conservation, restoration

Procedia PDF Downloads 118
419 Nazi Experiments during World War II: Dismal Period for Bioethics

Authors: Catharina O. Vianna Dias da Silva, Amanda F. Batista, Ana Clara C. Burgos Lessa, Carolina S. Lucchesi Ramacciotti, Maria Clara B. de Andrade, Roberto de B. Silva

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This article aims to analyze the bioethical aspects related to the historical practices of experiments on humans that occurred in Nazi Germany during the period of World War II (1939-1945). The method was based on the bibliographic review of articles published in databases such as SciELO and Pubmed. In the discussion, historical and humanistic aspects that contributed to the construction of a genocidal culture practiced during this period were analyzed. Additionally, an ethical question arises: should the information acquired during this dark period be used by science? After analysis, it was found that these Nazi experiments went over medical and ethical principles, being a deplorable milestone in history. It was also concluded that, although they generated potentially 'useful' results in the scientific field, they should be discarded as an ethical question of principle, of never daring to validate such a deplorable way of obtaining knowledge.

Keywords: Nazism, bioethics, human experimentation, human rights, genocide, torture, medicine

Procedia PDF Downloads 126
418 Geographic Information System Applications in Prioritizing Karlahi Forest Reserve Area for Conservation

Authors: Samuel Hyellamada Jerry

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This study focused on assessing conservation priorities within the Karlahi Forest Reserve of Fufore Local Government in Adamawa State. The main objective was to identify specific areas within the forest reserve that require immediate conservation attention. The research employed remote sensing and GIS techniques to achieve this goal. By overlaying the IDRIS Silva module results, a spatial distribution map was generated, highlighting the cumulative priority areas within and outside the forest. Among the total vegetated area of 26.38 km² in the Karlahi Forest Reserve, the analysis revealed that 16.16 km² were classified as high-priority conservation zones. Additionally, 4.59 km² and 5.63 km² were identified as medium and low-priority areas, respectively. In light of these findings, it is recommended that conservation efforts incorporate detailed land cover information and regular assessments of species diversity. Furthermore, strict adherence to national and state policies regarding forest reserves and parks is crucial for effective conservation management.

Keywords: priority, Karlahi, forest, reserve, IDRISI Silva, species diversity

Procedia PDF Downloads 113
417 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

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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 178
416 Multi-Objective Optimization of Combined System Reliability and Redundancy Allocation Problem

Authors: Vijaya K. Srivastava, Davide Spinello

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This paper presents established 3n enumeration procedure for mixed integer optimization problems for solving multi-objective reliability and redundancy allocation problem subject to design constraints. The formulated problem is to find the optimum level of unit reliability and the number of units for each subsystem. A number of illustrative examples are provided and compared to indicate the application of the superiority of the proposed method.

Keywords: integer programming, mixed integer programming, multi-objective optimization, Reliability Redundancy Allocation

Procedia PDF Downloads 133
415 Jatropha curcas L. Oil Selectivity in Froth Flotation

Authors: André C. Silva, Izabela L. A. Moraes, Elenice M. S. Silva, Carlos M. Silva Filho

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In Brazil, most soils are acidic and low in essential nutrients required for the growth and development of plants, making fertilizers essential for agriculture. As the biggest producer of soy in the world and a major producer of coffee, sugar cane and citrus fruits, Brazil is a large consumer of phosphate. Brazilian’s phosphate ores are predominantly from igneous rocks showing a complex mineralogy, associated with carbonites and oxides, typically iron, silicon and barium. The adopted industrial concentration circuit for this type of ore is a mix between magnetic separation (both low and high field) to remove the magnetic fraction and a froth flotation circuit composed by a reverse flotation of apatite (barite’s flotation) followed by direct flotation circuit (rougher, cleaner and scavenger circuit). Since the 70’s fatty acids obtained from vegetable oils are widely used as lower-cost collectors in apatite froth flotation. This is a very effective approach to the apatite family of minerals, being that this type of collector is both selective and efficient (high recovery). This paper presents Jatropha curcas L. oil (JCO) as a renewable and sustainable source of fatty acids with high selectivity in froth flotation of apatite. JCO is considerably rich in fatty acids such as linoleic, oleic and palmitic acid. The experimental campaign involved 216 tests using a modified Hallimond tube and two different minerals (apatite and quartz). In order to be used as a collector, the oil was saponified. The results found were compared with the synthetic collector, Fotigam 5806 produced by Clariant, which is composed mainly by soy oil. JCO showed the highest selectivity for apatite flotation with cold saponification at pH 8 and concentration of 2.5 mg/L. In this case, the mineral recovery was around 95%.

Keywords: froth flotation, jatropha curcas, microflotation, selectivity

Procedia PDF Downloads 394
414 Attitudes of Nurses towards End-of-Life Care for Themselves

Authors: H. N. S. Silva, S. N. Silva

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Introduction: 88.3% of physicians decided to choose a ‘no-code’ or a DNR order if hospitalized and would choose to die less aggressively at home. However, their wishes were mostly over ridden. Objective: To assess the attitudes of nurses towards the end-of-the-life care they would like to receive for themselves and their attitudes towards terminal illnesses. Methods: A mixed method approach was used. A closed and open-ended questionnaire was administered to 73 participants and 5 registered nurses, who have more than 10 years of experience, working in hospitals both in Sri Lanka and abroad, were interviewed. Results: 94.1% of the participants stated that they would like to die at home, spending their last hours at home surrounded by their loved ones and engaging in religious activities but 57.7% of unmarried nurse said they would agree on euthanasia if they had a terminal disease, and also 66.2% of them stated they would agree in DNR order if they happen to be admitted to the ICU, but 82.5% wanted to diagnose if they had a terminal illness or cancer but did not agree on euthanasia. Qualitative analysis confirmed the findings and revealed that despite having adequate confidence about the hospital care, nurses would choose to die at home, surrounded by their loved once and engaging in religious activities. Euthanasia was believed to be inappropriate as it is religiously incorrect and as death is a natural process. Conclusion: The perception of death among nurses depends on their religious belief.

Keywords: death, do not resuscitate, euthanasia, nurses

Procedia PDF Downloads 479
413 Media Planning Decisions and Preferences through a Goal Programming Model: An Application to a Media Campaign for a Mature Product in Italy

Authors: Cinzia Colapinto, Davide La Torre

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Goal Programming (GP) and its variants were applied to marketing and specific marketing issues, such as media scheduling problems in the last decades. The concept of satisfaction functions has been widely utilized in the GP model to explicitly integrate the Decision-Maker’s preferences. These preferences can be guided by the available information regarding the decision-making situation. A GP model with satisfaction functions for media planning decisions is proposed and then illustrated through a case study related to a marketing/media campaign in the Italian market.

Keywords: goal programming, satisfaction functions, media planning, tourism management

Procedia PDF Downloads 366
412 Evaluate the Kinetic Parameters and Characterize for Waste Prosopis juliflora Pods

Authors: Jean C. G. Silva, Kaline N. Ferreira, Rennio F. Sena, Flavio L. H. Silva

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The Prosopis juliflora (called algaroba in Northeastern Region of Brazil) is a species of medium to large size that can reach 18 meters high, being typical of arid and semi-arid regions by to requirement less water to survive; this is a fundamental attribute from its adaptation. It's considered of multiple uses, because the trunk, the fruit, and the algaroba pods are utilized for several purposes, among them, the production of wood from lumber mill, charcoal, alcohol, animal and human consumption, being hence, a culture of economic and social value. The use of waste Prosopis juliflora can be carried out for like pyrolysis and gasification processes, in order to energy production in those regions where it is grown. Thus this study aims to characterize the residue of the algaroba pods and evaluate the kinetic parameters, activation energy (Ea) and pre-exponential factor (k0), the devolatilization process through the data obtained from TG/DTG curves with different levels of heating rates. At work was used the heating rates of 5 K.min-1, 10 K.min-1, 15 K.min-1, 20 K.min-1 and 30 K.min-1, in inert nitrogen atmosphere (99.997%) under a flow of 40 ml.min-1. The kinetic parameters were obtained using the methods of Friedman and Ozawa-Flynn-Wall.

Keywords: activation energy, devolatilization, kinetic parameters, waste

Procedia PDF Downloads 352
411 A Genetic Algorithm Approach to Solve a Weaving Job Scheduling Problem, Aiming Tardiness Minimization

Authors: Carolina Silva, João Nuno Oliveira, Rui Sousa, João Paulo Silva

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This study uses genetic algorithms to solve a job scheduling problem in a weaving factory. The underline problem regards an NP-Hard problem concerning unrelated parallel machines, with sequence-dependent setup times. This research uses real data regarding a weaving industry located in the North of Portugal, with a capacity of 96 looms and a production, on average, of 440000 meters of fabric per month. Besides, this study includes a high level of complexity once most of the real production constraints are applied, and several real data instances are tested. Topics such as data analyses and algorithm performance are addressed and tested, to offer a solution that can generate reliable and due date results. All the approaches will be tested in the operational environment, and the KPIs monitored, to understand the solution's impact on the production, with a particular focus on the total number of weeks of late deliveries to clients. Thus, the main goal of this research is to develop a solution that allows for the production of automatically optimized production plans, aiming to the tardiness minimizing.

Keywords: genetic algorithms, textile industry, job scheduling, optimization

Procedia PDF Downloads 118
410 Analyzing the Impact of Bariatric Surgery in Obesity Associated Chronic Kidney Disease: A 2-Year Observational Study

Authors: Daniela Magalhaes, Jorge Pedro, Pedro Souteiro, Joao S. Neves, Sofia Castro-Oliveira, Vanessa Guerreiro, Rita Bettencourt- Silva, Maria M. Costa, Ana Varela, Joana Queiros, Paula Freitas, Davide Carvalho

Abstract:

Introduction: Obesity is an independent risk factor for renal dysfunction. Our aims were: (1) evaluate the impact of bariatric surgery (BS) on renal function; (2) clarify the factors determining the postoperative evolution of the glomerular filtration rate (GFR); (3) access the occurrence of oxalate-mediated renal complications. Methods: We investigated a cohort of 1448 obese patients who underwent bariatric surgery. Those with basal GFR (GFR0) < 30mL/min or without information about the GFR 2-year post-surgery (GFR2) were excluded. Results: We included 725 patients, of whom 647 (89.2%) women, with 41 (IQR 34-51) years, a median weight of 112.4 (IQR 103.0-125.0) kg and a median BMI of 43.4 (IQR 40.6-46.9) kg/m2. Of these, 459 (63.3%) performed gastric bypass (RYGB), 144 (19.9%) placed an adjustable gastric band (AGB) and 122 (16.8%) underwent vertical gastrectomy (VG). At 2-year post-surgery, excess weight loss (EWL) was 60.1 (IQR 43.7-72.4) %. There was a significant improve of metabolic and inflammatory status, as well as a significant decrease in the proportion of patients with diabetes, arterial hypertension and dyslipidemia (p < 0.0001). At baseline, 38 (5.2%) of subjects had hyperfiltration with a GFR0 ≥ 125mL/min/1.73m2, 492 (67.9%) had a GFR0 90-124 mL/min/1.73m2, 178 (24.6%) had a GFR0 60-89 mL/min/1.73m2, and 17 (2.3%) had a GFR0 < 60 mL/min/1.73m2. GFR decreased in 63.2% of patients with hyperfiltration (ΔGFR=-2.5±7.6), and increased in 96.6% (ΔGFR=22.2±12.0) and 82.4% (ΔGFR=24.3±30.0) of the subjects with GFR0 60-89 and < 60 mL/min/1.73m2, respectively ( p < 0.0001). This trend was maintained when adjustment was made for the type of surgery performed. Of 321 patients, 10 (3.3%) had a urinary albumin excretion (UAE) > 300 mg/dL (A3), 44 (14.6%) had a UAE 30-300 mg/dL (A2) and 247 (82.1%) has a UAE < 30 mg/dL (A1). Albuminuria decreased after surgery and at 2-year follow-up only 1 (0.3%) patient had A3, 17 (5.6%) had A2 and 283 (94%) had A1 (p < 0,0001). In multivariate analysis, the variables independently associated with ΔGFR were BMI (positively) and fasting plasma glucose (negatively). During the 2-year follow-up, only 57 of the 725 patients had transient urinary excretion of calcium oxalate crystals. None has records of oxalate-mediated renal complications at our center. Conclusions: The evolution of GFR after BS seems to depend on the initial renal function, as it decreases in subjects with hyperfiltration, but tends to increase in those with renal dysfunction. Our results suggest that BS is associated with improvement of renal outcomes, without significant increase of renal complications. So, apart the clear benefits in metabolic and inflammatory status, maybe obese adults with nondialysis-dependent CKD should be referred for bariatric surgery evaluation.

Keywords: albuminuria, bariatric surgery, glomerular filtration rate, renal function

Procedia PDF Downloads 311
409 Full-Wave Analysis of Magnetic Meta-Surfaces for Microwave Component Applications

Authors: Christopher Hardly Joseph, Nicola Pelagalli, Davide Mencarelli, Luca Pierantoni

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In this contribution, we report the electromagnetic response of a split ring resonator (SRR) based magnetic metamaterial unit cell in free space nature by means of a full-wave electromagnetic simulation. The effective parameters of these designed structures have been analyzed. The structures have been specifically designed to work at high frequency considering the development of many microwave and lower mm-wave devices. In addition to that, the application of the designed metamaterial structures is also proposed, namely metamaterial loaded planar transmission lines, potentially useful to optimize size and quality factor of circuit components and radiating elements.

Keywords: CPW, Microwave Components, Negative Permeability, Split Ring Resonator (SRR)

Procedia PDF Downloads 138
408 Advantages of Vibration in the GMAW Process for Improving the Quality and Mechanical Properties

Authors: C. A. C. Castro, D. C. Urashima, E. P. Silva, P. M. L. Silva

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Since 1920, the industry has almost completely changed the rivets production techniques for the manufacture of permanent welding join production of structures and manufacture of other products. The welding arc is the process more widely used in industries. This is accomplished by the heat of an electric arc which melts the base metal while the molten metal droplets are transferred through the arc to the welding pool, protected from the atmosphere by a gas curtain. The GMAW (Gas metal arc welding) process is influenced by variables such as: Current, polarity, welding speed, electrode, extension, position, moving direction; type of joint, welder's ability, among others. It is remarkable that the knowledge and control of these variables are essential for obtaining satisfactory quality welds, knowing that are interconnected so that changes in one of them requiring changes in one or more of the other to produce the desired results. The optimum values are affected by the type of base metal, the electrode composition, the welding position and the quality requirements. Thus, this paper proposes a new methodology, adding the variable vibration through a mechanism developed for GMAW welding, in order to improve the mechanical and metallurgical properties which does not affect the ability of the welder and enables repeatability of the welds made. For confirmation metallographic analysis and mechanical tests were made.

Keywords: vibration, joining, weldability, GMAW

Procedia PDF Downloads 395
407 Limestone Briquette Production and Characterization

Authors: André C. Silva, Mariana R. Barros, Elenice M. S. Silva, Douglas. Y. Marinho, Diego F. Lopes, Débora N. Sousa, Raphael S. Tomáz

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Modern agriculture requires productivity, efficiency and quality. Therefore, there is need for agricultural limestone implementation that provides adequate amounts of calcium and magnesium carbonates in order to correct soil acidity. During the limestone process, fine particles (with average size under 400#) are generated. These particles do not have economic value in agricultural and metallurgical sectors due their size. When limestone is used for agriculture purposes, these fine particles can be easily transported by wind generated air pollution. Therefore, briquetting, a mineral processing technique, was used to mitigate this problem resulting in an agglomerated product suitable for agriculture use. Briquetting uses compressive pressure to agglomerate fine particles. It can be aided by agglutination agents, allowing adjustments in shape, size and mechanical parameters of the mass. Briquettes can generate extra profits for mineral industry, presenting as a distinct product for agriculture, and can reduce the environmental liabilities of the fine particles storage or disposition. The produced limestone briquettes were subjected to shatter and water action resistance tests. The results show that after six minutes completely submerged in water, the briquettes where fully diluted, a highly favorable result considering its use for soil acidity correction.

Keywords: agglomeration, briquetting, limestone, soil acidity correction

Procedia PDF Downloads 354
406 Oral Biofilm and Stomatitis Denture: Local Implications and Cardiovascular Risks

Authors: Adriana B. Ribeiro, Camila B. Araujo, Frank L. Bueno, Luiz Eduardo V. Silva, Caroline V. Fortes, Helio C. Salgado, Rubens Fazan Jr., Claudia H. L. da Silva

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Denture-related stomatitis (DRS) has recently been associated with deleterious cardiovascular effects, including hypertension. This study evaluated salivary parameters, blood pressure (BP) and heart rate variability (HRV), before and after DRS treatment in edentulous patients (n=14). Collection of unstimulated and stimulated saliva, as well as blood pressure (BP) measurements and electrocardiogram recordings were performed before and after 10 days of DRS treatment. The salivary flow (mL/min) was found similar at both times while pH was smaller (more neutral) after treatment (7.3 ± 2.2 vs. 7.1 ± 0.24). Systolic BP (mmHg) showed a trend, but not a significant reduction after DRS treatment (158 ± 25.68 vs. 148 ± 16,72, p=0,062) while diastolic BP was found similar in both times (86 ± 13.93 and 84 ± 9.38). Overall HRV, measured by standard deviation of RR intervals was not affected by DRS treatment (24 ± 4 vs 18 ± 2 ms), but differences of successive RR intervals (an index of parasympathetic cardiac modulation) increased after the treatment (26 ± 4 vs 19 ± 2 ms). Moreover, another index of vagal modulation of the heart, the power of RR interval spectra at high-frequency, was also markedly higher after DRS treatment (236 ± 63 vs 135 ± 32 ms²). Such findings strongly suggest that DRS is linked to an autonomic imbalance with sympathetic overactivity, which is markedly deleterious, increasing cardiovascular risk and the incidence of diseases such as hypertension. Acknowledgment: This study is supported by FAPESP, CNPq.

Keywords: biofilm, denture stomatitis, HRV, blood pressure

Procedia PDF Downloads 197
405 Reasons behind Accounting Information Tools Adopted by Portuguese Third Sector Organizations: Institutional Theory versus Rational Choice Theory

Authors: Eurico Lima Basto, Ofélia Pinto, Anabela Silva, Amélia Ferreira-Da-Silva

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The purpose if this study is two-fold: on the one hand, to identify the accounting information systems implemented in third sector organizations, as well as its components, its tools and the decisions and control purposes they serve; on the other hand, and by confronting these two theories - institutional theory versus rational choice – we intent to go further by understanding the reasons behind the adoption of the aforementioned tools. Data has been collected from third sector organizations operating in Portugal. Our sample includes all juridical types of organizations such as foundations, cooperative, associations or private institutions of social solidarity. The questionnaire contained sixteen close-ended questions and four open-questions. Results confirm the theoretical perspective of institutionalism. Most third sector organizations operating in Portugal implemented only traditional accounting tools like standard accounting statements, cost accounting, budgeting. Moreover, there is clear evidence that the decisions about the implementation of these tools were coercive oriented. With this study it is intended to contribute to a better understanding of the context of third sector organizations in Portugal, in particular the role that accounting plays in this sector, with a special focus on management accounting tools, and the factors that influence their use and the degree of their usefulness in the process of decision making.

Keywords: third sector, accounting tools, institutional theory, Portugal, descriptive research

Procedia PDF Downloads 278
404 Food Safety in Wine: Removal of Ochratoxin a in Contaminated White Wine Using Commercial Fining Agents

Authors: Antònio Inês, Davide Silva, Filipa Carvalho, Luís Filipe-Riberiro, Fernando M. Nunes, Luís Abrunhosa, Fernanda Cosme

Abstract:

The presence of mycotoxins in foodstuff is a matter of concern for food safety. Mycotoxins are toxic secondary metabolites produced by certain molds, being ochratoxin A (OTA) one of the most relevant. Wines can also be contaminated with these toxicants. Several authors have demonstrated the presence of mycotoxins in wine, especially ochratoxin A. Its chemical structure is a dihydro-isocoumarin connected at the 7-carboxy group to a molecule of L-β-phenylalanine via an amide bond. As these toxicants can never be completely removed from the food chain, many countries have defined levels in food in order to attend health concerns. OTA contamination of wines might be a risk to consumer health, thus requiring treatments to achieve acceptable standards for human consumption. The maximum acceptable level of OTA in wines is 2.0 μg/kg according to the Commission regulation No. 1881/2006. Therefore, the aim of this work was to reduce OTA to safer levels using different fining agents, as well as their impact on white wine physicochemical characteristics. To evaluate their efficiency, 11 commercial fining agents (mineral, synthetic, animal and vegetable proteins) were used to get new approaches on OTA removal from white wine. Trials (including a control without addition of a fining agent) were performed in white wine artificially supplemented with OTA (10 µg/L). OTA analyses were performed after wine fining. Wine was centrifuged at 4000 rpm for 10 min and 1 mL of the supernatant was collected and added of an equal volume of acetonitrile/methanol/acetic acid (78:20:2 v/v/v). Also, the solid fractions obtained after fining, were centrifuged (4000 rpm, 15 min), the resulting supernatant discarded, and the pellet extracted with 1 mL of the above solution and 1 mL of H2O. OTA analysis was performed by HPLC with fluorescence detection. The most effective fining agent in removing OTA (80%) from white wine was a commercial formulation that contains gelatin, bentonite and activated carbon. Removals between 10-30% were obtained with potassium caseinate, yeast cell walls and pea protein. With bentonites, carboxymethylcellulose, polyvinylpolypyrrolidone and chitosan no considerable OTA removal was verified. Following, the effectiveness of seven commercial activated carbons was also evaluated and compared with the commercial formulation that contains gelatin, bentonite and activated carbon. The different activated carbons were applied at the concentration recommended by the manufacturer in order to evaluate their efficiency in reducing OTA levels. Trial and OTA analysis were performed as explained previously. The results showed that in white wine all activated carbons except one reduced 100% of OTA. The commercial formulation that contains gelatin, bentonite and activated carbon reduced only 73% of OTA concentration. These results may provide useful information for winemakers, namely for the selection of the most appropriate oenological product for OTA removal, reducing wine toxicity and simultaneously enhancing food safety and wine quality.

Keywords: wine, ota removal, food safety, fining

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403 Public Behavior When Encountered with a Road Traffic Accident

Authors: H. N. S. Silva, S. N. Silva

Abstract:

Introduction: The latest WHO data published in 2014 states that Sri Lanka has reached 2,773 of total deaths and over 14000 individuals’ sustained injuries due to RTAs each year. It was noticed in previous studies that policemen, three wheel drivers and also pedestrians were the first to respond to RTAs but the victim’s condition was aggravated due to unskilled attempts made by the responders while management of the victim’s wounds, moving and positioning of the victims and also mainly while transportation of the victims. Objective: To observe the practices of the urban public in Sri Lanka who are encountered with RTAs. Methods: A qualitative study was done to analyze public behavior seen on video recordings of scenes of accidents purposefully selected from social media, news websites, YouTube and Google. Results: The results showed that all individuals who tried to help during the RTA were middle aged men, who were mainly pedestrians, motorcyclists and policemen during that moment. Vast majority were very keen to actively help the victims to get to hospital as soon as possible and actively participated in providing 'aid'. But main problem was the first aid attempts were disorganized and uncoordinated. Even though all individuals knew how to control external bleeding, none of them was aware of spinal prevention techniques or management of limb injuries. Most of the transportation methods and transfer techniques used were inappropriate and more injury prone. Conclusions: The public actively engages in providing aid despite their inappropriate practices in giving first aid.

Keywords: encountered, pedestrians, road traffic accidents, urban public

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402 Mapping Environmental Complexity: A Strategic Tool for Sustainable Development of Road Infrastructure in Santa Catarina, Brazil

Authors: Edinei Coser, Cátia Regina Silva de Carvalho Pinto, Kleber Isaac Silva de Souza

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The road transportation system is an integral part of the Brazilian economy, so investing in this sector is paramount. Despite being a significant contributor to national and regional development, implementing road infrastructures brings about significant environmental changes, resulting in negative impacts that need to be mitigated through environmental licensing. However, by considering potential environmental impacts from a strategic perspective earlier, we can ensure that the sustainable development resulting from investments in this sector is more efficient. Therefore, this work aims to incorporate strategic environmental assessment into the road transportation system in the state of Santa Catarina using a tool that evaluates the entire territory. This tool analyzes 15 qualitative socio-environmental factors that may complicate environmental licensing and project implementation, with the help of multi-criteria analysis based on AHP and geographic information systems with Python, which presents a surface map of environmental cost for Santa Catarina state in Brazil. This map can assess potential areas for road implementation or paving, evaluate and propose road corridors, promote government programs and investments, and enhance contracting and environmental assessment processes.

Keywords: strategic environmental assessment, multi-criteria analysis, GIS (Geographic Information System), highways, environmental impact assessment.

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401 Optimal Consume of NaOH in Starches Gelatinization for Froth Flotation

Authors: André C. Silva, Débora N. Sousa, Elenice M. S. Silva, Thales P. Fontes, Raphael S. Tomaz

Abstract:

Starches are widely used as depressant in froth flotation operations in Brazil due to their efficiency, increasing the selectivity in the inverse flotation of quartz depressing iron ore. Starches market have been growing and improving in recent years, leading to better products attending the requirements of the mineral industry. The major source of starch used for iron ore is corn starch, which needs to be gelatinized with sodium hydroxide (NaOH) prior to use. This stage has a direct impact on industrials costs, once the lowest consumption of NaOH in gelatinization provides better control of the pH in the froth flotation and reduces the amount of electrolytes present in the pulp. In order to evaluate the gelatinization degree of different starches and flour were subjected to the addiction of NaOH and temperature variation experiments. Samples of starch (corn, cassava, HIPIX 100, HIPIX 101 and HIPIX 102 commercialized by Ingredion) and flour (cassava and potato) were tested. The starch samples were characterized through Scanning Electronic Microscopy and the amylose content were determined through spectrometry, swelling and solubility tests. The gelatinization was carried out through titration with NaOH, keeping the solution temperature constant at 40 oC. At the end of the tests, the optimal amount of NaOH consumed to gelatinize the starch or flour from different botanical sources was established and a correlation between the content of amylopectin in the starch and the starch/NaOH ratio needed for its gelatinization.

Keywords: froth flotation, gelatinization, sodium hydroxide, starches and flours

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400 A Combinatorial Representation for the Invariant Measure of Diffusion Processes on Metric Graphs

Authors: Michele Aleandri, Matteo Colangeli, Davide Gabrielli

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We study a generalization to a continuous setting of the classical Markov chain tree theorem. In particular, we consider an irreducible diffusion process on a metric graph. The unique invariant measure has an atomic component on the vertices and an absolutely continuous part on the edges. We show that the corresponding density at x can be represented by a normalized superposition of the weights associated to metric arborescences oriented toward the point x. A metric arborescence is a metric tree oriented towards its root. The weight of each oriented metric arborescence is obtained by the product of the exponential of integrals of the form ∫a/b², where b is the drift and σ² is the diffusion coefficient, along the oriented edges, for a weight for each node determined by the local orientation of the arborescence around the node and for the inverse of the diffusion coefficient at x. The metric arborescences are obtained by cutting the original metric graph along some edges.

Keywords: diffusion processes, metric graphs, invariant measure, reversibility

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399 The Development of Large Deformation Stability of Elastomeric Bearings

Authors: Davide Forcellini, James Marshal Kelly

Abstract:

Seismic isolation using multi-layer elastomeric isolators has been used in the United States for more than 20 years. Although isolation bearings normally have a large factor of safety against buckling due to low shear stiffness, this phenomenon has been widely studied. In particular, the linearly elastic theory adopted to study this phenomenon is relatively accurate and adequate for most design purposes. Unfortunately it cannot consider the large deformation response of a bearing when buckling occurs and the unresolved behaviour of the stability of the post-buckled state. The study conducted in this paper may be viewed as a development of the linear theory of multi-layered elastomeric bearing, simply replacing the differential equations by algebraic equations, showing how it is possible to evaluate the post-buckling behaviour and the interactions at large deformations.

Keywords: multi-layer elastomeric isolators, large deformation, compressive load, tensile load, post-buckling behaviour

Procedia PDF Downloads 396