Search results for: Harold Mauricio Díaz-Vargas
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 102

Search results for: Harold Mauricio Díaz-Vargas

72 Evaluation of Biogas Potential from Livestock in Malawi

Authors: Regina Kulugomba, Richard Blanchard, Harold Mapoma, Gregory Gamula, Stanley Mlatho

Abstract:

Malawi is a country with low energy access with only 10% of people having access to electricity and 97% of people relying on charcoal and fuel wood. The over dependence on the traditional biomass has brought in a number of negative consequences on people’s health and the environment. To curb the situation, the Government of Malawi (GoM), through its national policy of 2018 and charcoal strategies of 2007, identified biogas as a suitable alternative energy source for cooking. The GoM intends to construct tubular digesters across the country and one of the most crucial factors is the availability of livestock manure. The study was conducted to assess biogas potential from livestock manure by using Quantum Geographic information system (QGIS) software. Potential methane was calculated based on the population of livestock, amount of manure produced per capita and year, total solids, biogas yield and availability coefficient. The results of the study estimated biogas potential at 687 million m3 /year. Districts identified with highest biogas potential were Lilongwe, Ntcheu, Mangochi, Neno, Mwanza, Blantyre, Chiradzulu and Mulanje. The information will help investors and the Government of Malawi to locate potential sites for biogas plants installation.

Keywords: biogas, energy, feedstock, livestock

Procedia PDF Downloads 119
71 Relocation of the Air Quality Monitoring Stations Network for Aburrá Valley Based on Local Climatic Zones

Authors: Carmen E. Zapata, José F. Jiménez, Mauricio Ramiréz, Natalia A. Cano

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The majority of the urban areas in Latin America face the challenges associated with city planning and development problems, attributed to human, technical, and economical factors; therefore, we cannot ignore the issues related to climate change because the city modifies the natural landscape in a significant way transforming the radiation balance and heat content in the urbanized areas. These modifications provoke changes in the temperature distribution known as “the heat island effect”. According to this phenomenon, we have the need to conceive the urban planning based on climatological patterns that will assure its sustainable functioning, including the particularities of the climate variability. In the present study, it is identified the Local Climate Zones (LCZ) in the Metropolitan Area of the Aburrá Valley (Colombia) with the objective of relocate the air quality monitoring stations as a partial solution to the problem of how to measure representative air quality levels in a city for a local scale, but with instruments that measure in the microscale.

Keywords: air quality, monitoring, local climatic zones, valley, monitoring stations

Procedia PDF Downloads 242
70 A Composite Beam Element Based on Global-Local Superposition Theory for Prediction of Delamination in Composite Laminates

Authors: Charles Mota Possatti Júnior, André Schwanz de Lima, Maurício Vicente Donadon, Alfredo Rocha de Faria

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An interlaminar damage model is combined with a beam element formulation based on global-local superposition to assess delamination in composite laminates. The variations in the mechanical properties in the laminate, generated by the presence of delamination, are calculated as a function of the displacements in the interface layers. The global-local superposition of displacement fields ensures the zig-zag behaviour of stresses and displacement, and the number of degrees of freedom (DOFs) is independent of the number of layers. The displacements and stresses are calculated as a function of DOFs commonly used in traditional beam elements. Finally, the finite element(FE) formulation is extended to handle cases of different thicknesses, and then the FE model predictions are compared with results obtained from analytical solutions and commercial finite element codes.

Keywords: delamination, global-local superposition theory, single beam element, zig-zag, interlaminar damage model

Procedia PDF Downloads 82
69 Local Radial Basis Functions for Helmholtz Equation in Seismic Inversion

Authors: Hebert Montegranario, Mauricio Londoño

Abstract:

Solutions of Helmholtz equation are essential in seismic imaging methods like full wave inversion, which needs to solve many times the wave equation. Traditional methods like Finite Element Method (FEM) or Finite Differences (FD) have sparse matrices but may suffer the so called pollution effect in the numerical solutions of Helmholtz equation for large values of the wave number. On the other side, global radial basis functions have a better accuracy but produce full matrices that become unstable. In this research we combine the virtues of both approaches to find numerical solutions of Helmholtz equation, by applying a meshless method that produce sparse matrices by local radial basis functions. We solve the equation with absorbing boundary conditions of the kind Clayton-Enquist and PML (Perfect Matched Layers) and compared with results in standard literature, showing a promising performance by tackling both the pollution effect and matrix instability.

Keywords: Helmholtz equation, meshless methods, seismic imaging, wavefield inversion

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68 Effects of Net Height of Crab Entangling Nets on the Capture of Targeted Economically Important Portunid Species and Non-Target Species

Authors: Rizalyn Gonzales, Harold Monteclaro

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This study determined the effects of net height on the capture performance of crab entangling nets. Fishing trials were conducted using nets with the following net heights: 1) 12 meshes down (MD), 2) 24 MD and 3) 50 MD. A total of 1,290 individuals comprising of 87 species belonging to 53 families were caught. One-way ANOVA showed that net height significantly affects various catch parameters such as catch per unit effort (CPUE) of the total and target catch, amount of non-target catch, sizes and species richness. The use of appropriate net height is a potential technical measure for a selective but still efficient crab entangling net fishery. Lower net height significantly reduced non-target catch up to 70%. While lower nets decreased the CPUE of target catch such as blue swimming crab Portunus pelagicus and christian crab Charybdis feriatus up to 65% in 12 MD, catch in 24 MD was not significantly different with that in 50 MD. The use of 24 MD also resulted in capturing larger-sized Portunus pelagicus. Catch species richness decreased up to 58% in lower nets. These results are useful to fisheries managers and government institutions to develop or improve existing regulations towards a sustainable crab fishery particularly blue swimming crabs.

Keywords: blue swimming crabs, catch per unit effort, crab entangling nets, net height

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67 Forklift Allocation in Warehouse Operations with Restricted Halls

Authors: Mauricio Becerra Fernández, Olga Rosana Romero Quiroga, Elsa Cristina González La Rotta

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The logistics facilities design and construction is one of the strategic decisions that critically affects the performance of the company, from the economic perspective and relationship with customers. The case study company is the Colombian logistic sector leader, with over 60 years of experience, with sales of about one hundred twenty million dollars at the end of 2014. The preliminary design for the warehouse layout and operation includes a customer that provides approximately 17% of the profits of the company, considering the possibility of moving two forklifts in the warehouse halls. Some changes were not consider in previous stages of design, operations required forklift with different characteristics, whose size, do not allow the circulation of more than a forklift at a time. Therefore, it is necessary to assess the impact of this restriction on the warehouse operation, so decision makers implement actions to achieve efficient operation. The problem is addressed by recognizing logistics processes, which develop in a warehouse, collection of processes information behavior, the simulation of the current situation using ProModel software, model validation, making adjustments required, experiments design, conclusions and recommendations for the company.

Keywords: design, discrete events simulation, forklift allocation, logistics facilities, warehouse

Procedia PDF Downloads 272
66 Effects of Tool State on the Output Parameters of Front Milling Using Discrete Wavelet Transform

Authors: Bruno S. Soria, Mauricio R. Policena, Andre J. Souza

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The state of the cutting tool is an important factor to consider during machining to achieve a good surface quality. The vibration generated during material cutting can also directly affect the surface quality and life of the cutting tool. In this work, the effect of mechanical broken failure (MBF) on carbide insert tools during face milling of AISI 304 stainless steel was evaluated using three levels of feed rate and two spindle speeds for each tool condition: three carbide inserts have perfect geometry, and three other carbide inserts have MBF. The axial and radial depths remained constant. The cutting forces were determined through a sensory system that consists of a piezoelectric dynamometer and data acquisition system. Discrete Wavelet Transform was used to separate the static part of the signals of force and vibration. The roughness of the machined surface was analyzed for each machining condition. The MBF of the tool increased the intensity and force of vibration and worsened the roughness factors.

Keywords: face milling, stainless steel, tool condition monitoring, wavelet discrete transform

Procedia PDF Downloads 117
65 Reliability Based Investigation on the Choice of Characteristic Soil Properties

Authors: Jann-Eike Saathoff, Kirill Alexander Schmoor, Martin Achmus, Mauricio Terceros

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By using partial factors of safety, uncertainties due to the inherent variability of the soil properties and loads are taken into account in the geotechnical design process. According to the reliability index concept in Eurocode-0 in conjunction with Eurocode-7 a minimum safety level of β = 3.8 for reliability class RC2 shall be established. The reliability of the system depends heavily on the choice of the prespecified safety factor and the choice of the characteristic soil properties. The safety factors stated in the standards are mainly based on experience. However, no general accepted method for the calculation of a characteristic value within the current design practice exists. In this study, a laterally loaded monopile is investigated and the influence of the chosen quantile values of the deterministic system, calculated with p-y springs, will be presented. Monopiles are the most common foundation concepts for offshore wind energy converters. Based on the calculations for non-cohesive soils, a recommendation for an appropriate quantile value for the necessary safety level according to the standards for a deterministic design is given.

Keywords: asymptotic sampling, characteristic value, monopile foundation, probabilistic design, quantile values

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64 Decision Tree Model for the Recommendation of Digital and Alternate Payment Methods for SMEs

Authors: Arturo J. Anci Alméstar, Jose D. Fernandez Huapaya, David Mauricio

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Companies make erroneous decisions by not evaluating the inherent difficulties of entering electronic commerce without a prior review of current digital and alternate means of payment. For this reason, it is very important for businesses to have reliable, complete and integrated information on the means of current digital and alternate payments that allow decisions to be made about which of these to use. However, there is no such consolidated information or criteria that companies use to make decisions about the means of payment according to their needs. In this paper, we propose a decision tree model based on a taxonomy that presents us with a categorization of digital and alternative means of payment, as well as the visualization of the flow of information at a high level from the company to obtain a recommendation. This will allow the company to make the most appropriate decision about the implementation of the digital means of payment or alternative ideal for their needs, which allows a reduction in costs and complexity of the payment process. Likewise, the efficiency of the proposed model was evaluated through a satisfaction survey presented to company personnel, confirming the satisfactory quality level of the recommendations obtained by the model.

Keywords: digital payment medium, decision tree, decision making, digital payments taxonomy

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63 The Role of Questioning Techniques in a Literature Classroom

Authors: Barbara Magallona

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Given the observations between students who were active participants in a dialogue with their teacher and students who simply answered the teacher’s questions, the researcher will investigate the relationship between student-teacher dialogue in the classroom and the development of higher level thinking skills with an emphasis on the questioning techniques used by the teacher. The study posits the main question: What is the relationship between teachers’ questioning techniques and the development of students’ higher level thinking skills in a literature class (or in literature classes) in Xavier? The following are the study’s sub-questions: a) What types of questions do literature teachers at Xavier School ask? b) What types of responses do literature students at Xavier School give to teachers' questions? c) To what extent is the development of students' higher level thinking skills shown in teacher-student classroom dialogues in Xavier School's literature classroom? Since questioning techniques and student responses in the literature classroom form the core of this paper and in order to evaluate them, the study uses Andersen and Krathwohl’s revision of Harold Bloom’s Taxonomy of Educational Objectives. Teun van Dijk’s discourse-cognition-society triangle will be used as a theoretical framework to design and to guide the classroom interaction.

Keywords: discourse analysis, literature classroom, questioning techniques, secondary education

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62 Numerical Study for the Estimation of Hydrodynamic Current Drag Coefficients for the Colombian Navy Frigates Using Computational Fluid Dynamics

Authors: Mauricio Gracia, Luis Leal, Bharat Verma

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Computational fluid dynamics (CFD) has become nowadays an important tool in the process of hydrodynamic design of modern ships. CFD is used to model any phenomena related to fluid flow in a control volume like a ship or any offshore structure in the sea. In the present study, the current force drag coefficients for a Colombian Navy Frigate in deep and shallow water are estimated through the application of CFD. The study shows the process of simulating the ship current drag coefficients using the CFD simulations method, which is conducted using STAR-CCM+ software package. The Almirante Padilla class Frigate ship scale model is investigated. The results show the ship current drag coefficient calculated considering a current speed of 1 knot with a 90° drift angle for the full-scale ship. Predicted results were compared against the current drag coefficients published in the Lloyds register OCIMF report. It is shown that the simulation results agree fairly well with the published results and that STAR-CCM+ code can predict current drag coefficients.

Keywords: CFD, current draft coefficient, STAR-CCM+, OCIMF, Bollard pull

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61 Implementation of an Open Source ERP for SMEs in the Automotive Sector in Peru: A Case Study

Authors: Gerson E. Cornejo, Luis A. Gamarra, David S. Mauricio

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The Enterprise Resource Planning Systems (ERP) allows the integration of all the business processes of the functional areas of the companies, in order to automate and standardize the processes, obtain accurate information and improve decision making in time real. In Peru, 79% of medium and small companies (SMEs) do not use any management software, this is because it is believed that ERPs are expensive, complex and difficult to implement. However, for more than 20 years there have been Open Source ERPs, which are more accessible and have the same benefit as proprietary ERPs, but there is little information on the implementation process. In this work is made a case of study, in order to show the implementation process of an Open Source ERP, Odoo, based on the ASAP methodology (Accelerated SAP) and applied to a company of corrective and preventive maintenance services of vehicles. The ERP allowed the SME to standardize its business processes, increase its productivity, reducing up to 40% certain processes. The study of this case shows that it is feasible and profitable to implement an Open Source ERP in SMEs in the Automotive Sector of Peru. In addition, it is shown that the ASAP methodology is adequate to carry out Open Source ERPs implementation projects.

Keywords: ASAP, automotive sector, ERP implementation, open source

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60 Under the Veneer of Words Lies Power: Foucauldian Analysis of Oleanna

Authors: Diba Arjmandi

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The notion of power and gender domination is one of the inseparable aspects of themes in postmodern literature. The reason of its importance has been discussed frequently since the rise of Michel Foucault and his vantage point toward the circulation of power and the transgression of forces. The language and society act as the basic grounds for the study, as all human beings are bound to the set of rules and norms which shape them in the acceptable way in the macrocosm. How different genders in different positions behave and show reactions to the provocation of social forces and superiority of one another, is of great interest to writers and literary critics. Mamet’s works are noticeable for their controversial but timely themes which illustrate the human conflict with the community and greed for power. Many critics like Christopher Bigsby and Harold Bloom have been discussing Mamet and his ideas during recent years. This paper is the study of Oleanna, Mamet’s masterpiece about teacher-student relationship and the circulation of power between a man and woman. He shows the very breakable boundaries in domination of a gender and the downfall of speech as the consequence of transgression and freedom. The failure of the language the teacher uses and the abuses of his own words by a student who seeks superiority and knowledge are the main subjects of discussion. Supported by the ideas of Foucault, the language Mamet uses to represent his characters becomes the fundamental element of this survey. As a result, language becomes both the means of achievement and also downfall.

Keywords: domination, foucault, language, mamet, oleanna, power, transgression

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59 Ideological and Poetological Tensions: Wu Mi’s Enterprise of Imitating and Translating George Gordon Byron

Authors: Hanjin Yan

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The English Romantic George Gordon Byron (1788-1824) was widely celebrated by men of letters in early republican China as a Satanic freedom fighter challenging classical poetics and traditional values. However, Wu Mi (1894-1978), the most persistent critic of contemporary iconoclasm, perceived Byron as a paragon of self-righteous poet-exiles who maintained moral integrity and achieved poetic excellence during times of frustration, just like canonized classical Chinese poets. Wu Mi not only composed lengthy imitations of the third canto of Byron’s Childe Harold’s Pilgrimage (1816) but also patronized a rendering of the canto. Taking André Lefevere’s rewriting theory as a framework, this paper explores the interplay of ideology and poetics by examining Wu Mi’s imitations against Byron’s original and its Chinese translation patronized by Wu Mi. Textual analysis shows that Wu Mi’s approach to Byron’s poetry was informed not only by his endeavor to invigorate classical Chinese poetics, but also by his program to preserve China’s cultural traditions and integrate Western new humanism, a theory proposed by his Harvard mentor Irving Babbitt (1865-1933). This study reveals how Byron was appropriated to serve conflicting poetic and ideological purposes in early republican China and suggests that imitation as a type of rewriting merits further attention.

Keywords: George Gordon Byron, ideology, imitation, poetics, translation

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58 A Comprehensive CFD Model for Sugar-Cane Bagasse Heterogeneous Combustion in a Grate Boiler System

Authors: Daniel José de Oliveira Ferreira, Juan Harold Sosa-Arnao, Bruno Cássio Moreira, Leonardo Paes Rangel, Song Won Park

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The comprehensive CFD models have been used to represent and study the heterogeneous combustion of biomass. In the present work, the operation of a global flue gas circuit in the sugar-cane bagasse combustion, from wind boxes below primary air grate supply, passing by bagasse insertion in swirl burners and boiler furnace, to boiler bank outlet is simulated. It uses five different meshes representing each part of this system located in sequence: wind boxes and grate, boiler furnace, swirl burners, super heaters and boiler bank. The model considers turbulence using standard k-ε, combustion using EDM, radiation heat transfer using DTM with 16 ray directions and bagasse particle tracking represented by Schiller-Naumann model. The results showed good agreement with expected behavior found in literature and equipment design. The more detailed results view in separated parts of flue gas system allows to observe some flow behaviors that cannot be represented by usual simplifications like bagasse supply under homogeneous axial and rotational vectors and others that can be represented using new considerations like the representation of 26 thousand grate orifices by 144 rectangular inlets.

Keywords: comprehensive CFD model, sugar-cane bagasse combustion, sugar-cane bagasse grate boiler, axial

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57 Semiautomatic Calculation of Ejection Fraction Using Echocardiographic Image Processing

Authors: Diana Pombo, Maria Loaiza, Mauricio Quijano, Alberto Cadena, Juan Pablo Tello

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In this paper, we present a semi-automatic tool for calculating ejection fraction from an echocardiographic video signal which is derived from a database in DICOM format, of Clinica de la Costa - Barranquilla. Described in this paper are each of the steps and methods used to find the respective calculation that includes acquisition and formation of the test samples, processing and finally the calculation of the parameters to obtain the ejection fraction. Two imaging segmentation methods were compared following a methodological framework that is similar only in the initial stages of processing (process of filtering and image enhancement) and differ in the end when algorithms are implemented (Active Contour and Region Growing Algorithms). The results were compared with the measurements obtained by two different medical specialists in cardiology who calculated the ejection fraction of the study samples using the traditional method, which consists of drawing the region of interest directly from the computer using echocardiography equipment and a simple equation to calculate the desired value. The results showed that if the quality of video samples are good (i.e., after the pre-processing there is evidence of an improvement in the contrast), the values provided by the tool are substantially close to those reported by physicians; also the correlation between physicians does not vary significantly.

Keywords: echocardiography, DICOM, processing, segmentation, EDV, ESV, ejection fraction

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56 Assessment of Pier Foundations for Onshore Wind Turbines in Non-cohesive Soil

Authors: Mauricio Terceros, Jann-Eike Saathoff, Martin Achmus

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In non-cohesive soil, onshore wind turbines are often found on shallow foundations with a circular or octagonal shape. For the current generation of wind turbines, shallow foundations with very large breadths are required. The foundation support costs thus represent a considerable portion of the total construction costs. Therefore, an economic optimization of the type of foundation is highly desirable. A conceivable alternative foundation type would be a pier foundation, which combines the load transfer over the foundation area at the pier base with the transfer of horizontal loads over the shaft surface of the pier. The present study aims to evaluate the load-bearing behavior of a pier foundation based on comprehensive parametric studies. Thereby, three-dimensional numerical simulations of both pier and shallow foundations are developed. The evaluation of the results focuses on the rotational stiffnesses of the proposed soil-foundation systems. In the design, the initial rotational stiffness is decisive for consideration of natural frequencies, whereas the rotational secant stiffness for a maximum load is decisive for serviceability considerations. A systematic analysis of the results at different load levels shows that the application of the typical pier foundation is presumably limited to relatively small onshore wind turbines.

Keywords: onshore wind foundation, pier foundation, rotational stiffness of soil-foundation system, shallow foundation

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55 Kinetic Study of the Esterification of Unsaturated Fatty Acids from Salmon Oil (Salmosalar L.)

Authors: André Luis Lima de Oliveira, Vera Lúcia Viana do Nascimento, Victória Maura Silva Bermudez, Mauricio Nunes Kleinberg, João Carlos da Costa Assunção, José Osvaldo Beserra Carioca

Abstract:

The objective of this study was to synthesize a triglyceride with high content of unsaturated fatty acids from salmon oil (Salmo salar L.) by esterification with glycerol catalyzed dealuminized zeolite. A kinetic study was conducted to determine the reaction order and the activation energy. A statistical study was conducted to determine optimal reaction conditions. Initially, the crude oil was refined salmon physically and chemically. The crude oil was hydrolyzed and unsaturated free fatty acids were separated by urea complexation method. An experimental project to verify the parameters (temperature, glycerin and catalyst) with the greatest impact on the reaction was developed. In experiments aliquots were taken at predetermined times to measure the amount of free fatty acids. Pareto, surface, contour and hub graphs were used to determine the factors that maximized the reaction. According to the graphs the best reaction conditions were: temperature 80 ° C, the proportion glycerine/oil 5: 1 and 1% of catalyst. The kinetic data showed that the system was compatible with a second-order reaction. After analyzing the rate constant versus temperature charts a value of 85.31 kJ/mol was obtained for the reaction activation energy.

Keywords: esterification, kinect, oil, salmon

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54 The Exercise of Deliberative Democracy on Public Administrations Agencies' Decisions

Authors: Mauricio Filho, Carina Castro

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The object of this project is to analyze long-time public agents that passed through several governments and see themselves in the position of having to deliberate with new agents, recently settled in the public administration. For theoretical ends, internal deliberation is understood as the one practiced on the public administration agencies, without any direct participation from the general public in the process. The assumption is: agents with longer periods of public service tend to step away from momentary political discussions that guide the current administration and seek to concentrate on institutionalized routines and procedures, making the most politically aligned individuals with the current government deliberate with less "passion" and more exchanging of knowledge and information. The theoretical framework of this research is institutionalism, which is guided by a more pragmatic view, facing the fluidity of reality in ways showing the multiple relations between agents and their respective institutions. The critical aspirations of this project rest on the works of professors Cass Sunstein, Adrian Vermeule, Philipp Pettit and in literature from both institutional theory and economic analysis of law, greatly influenced by the Chicago Law School. Methodologically, the paper is a theoretical review and pretends to be unfolded, in a future moment, in empirical tests for verification. This work has as its main analytical tool the appeal to theoretical and doctrinaire areas from the Juridical Sciences, by adopting the deductive and analytical method.

Keywords: institutions, state, law, agencies

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53 Determination of Hydrolisis Condition in the Extraction of Fatty Acids from Pinchagua's (Opisthonema libertate) Heads, a By-Product of Sardine Industry

Authors: Belen Carrillo, Mauricio Mosquera

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Fatty acids are bioactive compounds widely used as nutritional supplements in the food and pharmaceutical industry. Bluefish such as sardines have a large variety of these fatty acids in their composition. The objective of this project is to extract these compounds from fishing wastes, to do this, heads of known species as Pinchagua (Opistonema libertate) were used. The conducted study represents a simplified alternative for obtaining and simultaneous saponification of oil through basic hydrolysis, which separates lipids from protein and saponifies sample all the same time to isolate the fatty acid accurately through salts formation. To do these different concentrations of sodium hydroxide were used, it was demonstrated at a concentration of 1 M the highest yield of saponified oil recovery corresponding a value of 3,64% was obtained. Subsequently, the saponified oil was subjected to an acid hydrolysis in which fatty acids were isolated. Different sulfuric acid concentrations and temperatures for the process were tested. Thus, it was shown that the great fatty acids variety were obtained at a 60 °C temperature and sulfuric acid concentration of 50% v/v. Among the obtained compounds the presence of acids such as palmitic, lauric, caproic and myristic are highlighted. Applications of this type of elements are varied and widely used in the nutritional supplements development. Thus, the described methodology proposes a simple mechanism in the revaluation of fishing industry wastes that allow directly generate high added value elements.

Keywords: fatty acids, hydrolysis, Pinchagua, saponification

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52 Influence of Concrete Cracking in the Tensile Strength of Cast-in Headed Anchors

Authors: W. Nataniel, B. Lima, J. Manoel, M. P. Filho, H. Marcos, Oliveira Mauricio, P. Ferreira

Abstract:

Headed reinforcement bars are increasingly used for anchorage in concrete structures. Applications include connections in composite steel-concrete structures, such as beam-column joints, in several strengthening situations as well as in more traditional uses in cast-in-place and precast structural systems. This paper investigates the reduction in the ultimate tensile capacity of embedded cast-in headed anchors due to concrete cracking. A series of nine laboratory tests are carried out to evaluate the influence of cracking on the concrete breakout strength in tension. The experimental results show that cracking affects both the resistance and load-slip response of the headed bar anchors. The strengths measured in these tests are compared to theoretical resistances calculated following the recommendations presented by fib Bulletin no. 58 (2011), ETAG 001 (2010) and ACI 318 (2014). The influences of parameters such as the effective embedment depth (hef), bar diameter (ds), and the concrete compressive strength (fc) are analysed and discussed. The theoretical recommendations are shown to be over-conservative for both embedment depths and were, in general, inaccurate in comparison to the experimental trends. The ACI 318 (2014) was the design code which presented the best performance regarding to the predictions of the ultimate load, with an average of 1.42 for the ratio between the experimental and estimated strengths, standard deviation of 0.36, and coefficient of variation equal to 0.25.

Keywords: cast-in headed anchors, concrete cone failure, uncracked concrete, cracked concrete

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51 Contextualizing Communication through Culture and Social Structure: An Exploration of Media Life

Authors: Jyoti Ranjan Sahoo

Abstract:

Communication is a social phenomenon which mediates to our everyday life and it creates, maintains, builds, circulates, and propagates for a common identity the society. The symbolic forms of communication such as aural, sounds, oral expressions, signs, and language as means of communication are being used in everyday life in helping to identify as construction of social reality. These symbolic forms of communication are treated as the social process in everyday life. Therefore, there is an intrinsic relationship between communication and culture to understand media life for village communities. Similarly, the interface of communication with social life is reflected upon it’s formulation of the notions of social structure and culture. It has been observed that there is an overlapping and new phenomenonal change of media life among marginalized communities in general and village communities in particular. Therefore, this paper is an outcome of decadal stock of literature and an empirical investigation on understanding of communication in a tribal village in India. It has examined the idea of American scientist Edward T. Hall “the culture is communication, and the communication is culture” in village society on understanding media life. Thus, the Harold Innis’s theoretical idea of “communication” has been critically examined in these contexts since author tries to explore and understand the inter-disciplinarity on understanding media life through communication and culture which is embedded in socio-cultural life bearing on epistemological and ontological implications. The paper tries to explore and understand the inter-disciplinary and historical trajectories of communication embedded with other social science disciplines; and also tries to map these studies relevant for the future directions and engagement which would have bearing on epistemological and ontological implications in the field of media and communication.

Keywords: culture, communication, history, media, oral, tradition

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50 Study of Corrosion Behavior of Experimental Alloys with Different Levels of Cr and High Levels of Mo Compared to Aisi 444

Authors: Ana P. R. N. Barroso, Maurício N. Kleinberg, Frederico R. Silva, Rodrigo F. Guimarães, Marcelo M. V. Parente, Walney S. Araújo

Abstract:

The fight against accelerated wear of the equipment used in the oil and gas sector is a challenge for minimizing maintenance costs. Corrosion being one of the main agents of equipment deterioration, we seek alternative materials that exhibit improved corrosion resistance at low cost of production. This study aims to evaluate the corrosion behavior of experimental alloys containing 15% and 17% of chromium (Cr) and 5% of molybdenum (Mo) in comparison with an AISI 444 commercial alloy. Microstructural analyzes were performed on samples of the alloys before and after the electrochemical tests. Two samples of each solubilized alloy were also taken for analysis of the corrosion behavior by testing potentiodynamic polarization (PP) and Electrochemical Impedance Spectroscopy (EIS) with immersion time of 24 hours in electrolytic solution with acidic character. The graphics obtained through electrochemical tests of PP and EIS indicated that among the experimental alloys, the alloy with higher chromium content (17%) had a higher corrosion resistance, confirming the beneficial effect of adding chromium. When comparing the experimental alloys with the AISI 444 commercial alloy, it is observed that the AISI 444 commercial alloy showed superior corrosion resistance to that of the experimental alloys for both assays, PP and EIS. The microstructural analyzes performed after the PP and EIS tests confirmed the results previously described. These results suggest that the addition of these levels of molybdenum did not favor the electrochemical behavior of experimental ferritic alloys for the electrolytic medium studied.

Keywords: corrosion, molybdenum, electrochemical tests, experimental alloys

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49 'Infection in the Sentence': The Castration of a Black Woman's Dream of Authorship as Manifested in Buchi Emecheta's Second Class Citizen

Authors: Aseel Hatif Jassam, Hadeel Hatif Jassam

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The paper discusses the phallocentric discourse that is challenged by women in general and of women of color in particular in spite of the simultaneity of oppression due to race, class, and gender in the diaspora. Therefore, the paper gives a brief account of women's experience in the light of postcolonial feminist theory. The paper also cast light on the theories of Luce Irigaray and Helen Cixous, two Feminist theorists who support and advise women to have their own discourse to challenge the infectious patriarchal sentence advocated by Sigmund Freud and Harold Bloom's model of literary history. Black women authors like BuchiEmecheta as well as her alter ego Adah, a Nigerian-born girl and the protagonist of her semi-autobiographical novel, Second Class Citizen, suffer from this phallocentric and oppressive sentence and displacement as they migrate from Nigeria, a former British colony where they feel marginalized to North London with the hope of realizing their dreams. Yet, in the British diaspora, they get culturally shocked and continue to suffer from further marginalization due to class and race and are insulted and interiorized ironically by their patriarchal husbands who try to put an end to their dreams of authorship. With the phallocentric belief that women aren't capable of self-representation in the background of their mindsets, the violent Sylvester Onwordi and Francis Obi, the husbands of both Emecheta and Adah, respectively have practiced oppression on them by burning their own authoritative voice, represented by the novels they write while they are struggling with their economically atrocious living experience in the British diaspora.

Keywords: authorship, British diaspora, discourse, phallocentric, patriarchy

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48 Influence of Aluminum Content on the Microstructural, Mechanical and Tribological Properties of TiAlN Coatings for Using in Dental and Surgical Instrumentation

Authors: Hernan D. Mejia, Gilberto B. Gaitan, Mauricio A. Franco

Abstract:

420 steel is normally used in the manufacture of dental and surgical instrumentation, as well as parts in the chemical, pharmaceutical, and food industries, among others, where they must withstand heavy loads and often be in contact with corrosive environments, which leads to wear and deterioration of these steels in relatively short times. In the case of medical applications, the instruments made of this steel also suffer wear and corrosion during the repetitive sterilization processes due to the relatively low achievable hardness of just 50 HRC and its hardly acceptable resistance to corrosion. In order to improve the wear resistance of 420 steel, TiAlN coatings were deposited, increasing the aluminum content in the alloy by varying the power applied to the aluminum target of 900, 1100, and 1300 W. Evaluations using XRD, Micro Raman, XPS, AFM, SEM, and TEM showed a columnar growth crystal structure with an average thickness of 2 microns and consisting of the TiN and TiAlN phases, whose roughness and grain size decrease with a higher Al content. The AlN phase also appears in the sample deposited at 1300W. The hardness, determined by nanoindentation, initially increases with the aluminum content from 9.7 GPa to 17.1 GPa, but then decreases to 15.4 GPa for the sample with the highest aluminum content due to the appearance of hexagonal AlN and a decrease of harder TiN and TiAlN phases. It was observed that the wear coefficient had a contrary behavior, which took values of 2.7; 1.7 and 6.6x10⁻⁶ mm³/N.m, respectively. All the coated samples significantly improved the wear resistance of the uncoated 420 steel.

Keywords: hard coatings, magnetron sputtering, TiAlN coatings, surgical instruments, wear resistance

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47 Dimensional Investigation of Food Addiction in Individuals Who Have Undergone Bariatric Surgery

Authors: Ligia Florio, João Mauricio Castaldelli-Maia

Abstract:

Background: Food addiction (FA) emerged in the 1990s as a possible contributor to the increasing prevalence of obesity and overweight, in conjunction with changing food environments and mental health conditions. However, FA is not yet listed as one of the disorders in the DSM-5 and/or the ICD-11. Although there are controversies and debates in the literature about the classification and construct of FA, the most common approach to access it is the use of a research tool - the Yale Food Addiction Scale (YFAS) - which approximates the concept of FA to the concept diagnosis of dependence on psychoactive substances. There is a need to explore the dimensional phenotypes accessed by YFAS in different population groups for a better understanding and scientific support of FA diagnoses. Methods: The primary objective of this project was to investigate the construct validity of the FA concept by mYFAS 2.0 in individuals who underwent bariatric surgery (n = 100) at the Hospital Estadual Mário Covas since 2011. Statistical analyzes were conducted using the STATA software. In this sense, structural or factor validity was the type of construct validity investigated using exploratory factor analysis (EFA) and item response theory (IRT) techniques. Results: EFA showed that the one-dimensional model was the most parsimonious. The IRT showed that all criteria contributed to the latent structure, presenting discrimination values greater than 0.5, with most presenting values greater than 2. Conclusion: This study reinforces a FA dimension in patients who underwent bariatric surgery. Within this dimension, we identified the most severe and discriminating criteria for the diagnosis of FA.

Keywords: obesity, food addiction, bariatric surgery, regain

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46 Political Regimes, Political Stability and Debt Dependence in African Countries of Franc Zone: A Logistic Modeling

Authors: Nounamo Nguedie Yann Harold

Abstract:

The factors behind the debt have been the subject of several studies in the literature. Pioneering studies based on the 'double deficit' approach linked indebtedness to the imbalance between savings and investment, the budget deficit and the current account deficit. Most studies on identifying factors that may stimulate or reduce the level of external public debt agree that the following variables are important explanatory variables in leveraging debt: the budget deficit, trade opening, current account and exchange rate, import, export, interest rate, term variation exchange rate, economic growth rate and debt service, capital flight, and over-indebtedness. Few studies addressed the impact of political factors on the level of external debt. In general, however, the IMF's stabilization programs in developing countries following the debt crisis have resulted in economic recession and the advent of political crises that have resulted in changes in governments. In this sense, political institutions are recognised as factors of accumulation of external debt in most developing countries. This paper assesses the role of political factors on the external debt level of African countries in the Franc Zone over the period 1985-2016. Data used come from World Bank and ICRG. Using a logit in panel, the results show that the more a country is politically stable, the lower the external debt compared to the gross domestic product. Political stability multiplies 1.18% the chances of being in the sustainable debt zone. For example, countries with good political institutions experience less severe external debt burdens than countries with bad political institutions.

Keywords: African countries, external debt, Franc Zone, political factors

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45 Introgressive Hybridisation between Two Widespread Sharks in the East Pacific Region

Authors: Diana A. Pazmino, Lynne vanHerwerden, Colin A. Simpfendorfer, Claudia Junge, Stephen C. Donnellan, Mauricio Hoyos-Padilla, Clinton A. J. Duffy, Charlie Huveneers, Bronwyn Gillanders, Paul A. Butcher, Gregory E. Maes

Abstract:

With just a handful of documented cases of hybridisation in cartilaginous fishes, shark hybridisation remains poorly investigated. Small amounts of admixture have been detected between Galapagos (Carcharhinus galapagensis) and dusky (Carcharhinus obscurus) sharks previously, generating a hypothesis of ongoing hybridisation. We sampled a large number of individuals from areas where both species co-occur (contact zones) across the Pacific Ocean and used both mitochondrial and nuclear-encoded SNPs to examine genetic admixture and introgression between the two species. Using empirical, analytical approaches and simulations, we first developed a set of 1,873 highly informative and reliable diagnostic SNPs for these two species to evaluate the degree of admixture between them. Overall, results indicate a high discriminatory power of nuclear SNPs (FST=0.47, p < 0.05) between the two species, unlike mitochondrial DNA (ΦST = 0.00 p > 0.05), which failed to differentiate between these species. We identified four hybrid individuals (~1%) and detected bi-directional introgression between C. galapagensis and C. obscurus in the Gulf of California along the eastern Pacific coast of the Americas. We emphasize the importance of including a combination of mtDNA and diagnostic nuclear markers to properly assess species identification, detect patterns of hybridisation, and better inform management and conservation of these sharks, especially given the morphological similarities within the genus Carcharhinus.

Keywords: elasmobranchs, single nucleotide polymorphisms, hybridisation, introgression, misidentification

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44 Groundhog Day as a Model for the Repeating Spectator and the Film Academic: Re-Watching the Same Films Again Can Create Different Experiences and Ideas

Authors: Leiya Ho Yin Lee

Abstract:

Groundhog Day (Harold Ramis, 1993) may seemingly be a fairly unremarkable Hollywood comedy film in the 90s, it is argued that the film, with its protagonist Phil (Bill Murray), inadvertently, but perfectly, demonstrates an important aspect in filmmaking, film spectatorship and film research: repetition. Very rarely does a narrative film use one, and only one, take in its shooting. The multiple ‘repeats’ of Phil’s various endeavours due to his being trapped in a perpetual loop of the same day — from stealing money and tricking a woman into a casual relationship, to his multiple suicides, to eventually helping people in need — make the process of doing multiple ‘takes’ in filmmaking explicit. But perhaps more significantly, Phil represents a perfect model for the spectator/cinephile who has seen their favourite film for multiple times that they can remember every single detail. Crucially, their favourite film never changes, as it is a recording, but the cinephile’s experience of that very same film is most likely different each time they watch it again, just as Phil’s character and personality has completely transformed, from selfish and egotistic, to depressed and nihilistic, and ultimately to sympathetic and caring, even though he is living the exact same day. Furthermore, the author did not come up with this stimulating juxtaposition of film spectatorship and Groundhog Day the first time the author saw the film; it took the author a few casual re-viewings to notice the film’s self-reflexivity. And then, when working on it in the author’s research, the author had to re-view the film for more times, and have subsequently noticed even more things previously unnoticed. In this way, Groundhog Day not only stands for a model for filmmaking and film spectatorship, it also illustrates the act of academic research, especially in Film Studies where repeatedly viewing the same films is a prerequisite before new ideas and concepts are discovered from old material. This also recalls Deleuze’s thesis on difference and repetition in that repetition creates difference and it is difference that creates thought.

Keywords: narrative comprehension, repeated viewing, repetition, spectatorship

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43 Computerized Analysis of Phonological Structure of 10,400 Brazilian Sign Language Signs

Authors: Wanessa G. Oliveira, Fernando C. Capovilla

Abstract:

Capovilla and Raphael’s Libras Dictionary documents a corpus of 4,200 Brazilian Sign Language (Libras) signs. Duduchi and Capovilla’s software SignTracking permits users to retrieve signs even when ignoring the gloss corresponding to it and to discover the meaning of all 4,200 signs sign simply by clicking on graphic menus of the sign characteristics (phonemes). Duduchi and Capovilla have discovered that the ease with which any given sign can be retrieved is an inverse function of the average popularity of its component phonemes. Thus, signs composed of rare (distinct) phonemes are easier to retrieve than are those composed of common phonemes. SignTracking offers a means of computing the average popularity of the phonemes that make up each one of 4,200 signs. It provides a precise measure of the degree of ease with which signs can be retrieved, and sign meanings can be discovered. Duduchi and Capovilla’s logarithmic model proved valid: The degree with which any given sign can be retrieved is an inverse function of the arithmetic mean of the logarithm of the popularity of each component phoneme. Capovilla, Raphael and Mauricio’s New Libras Dictionary documents a corpus of 10,400 Libras signs. The present analysis revealed Libras DNA structure by mapping the incidence of 501 sign phonemes resulting from the layered distribution of five parameters: 163 handshape phonemes (CherEmes-ManusIculi); 34 finger shape phonemes (DactilEmes-DigitumIculi); 55 hand placement phonemes (ArtrotoToposEmes-ArticulatiLocusIculi); 173 movement dimension phonemes (CinesEmes-MotusIculi) pertaining to direction, frequency, and type; and 76 Facial Expression phonemes (MascarEmes-PersonalIculi).

Keywords: Brazilian sign language, lexical retrieval, libras sign, sign phonology

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