Search results for: Wendy Carolina Gomez Ramirez
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 391

Search results for: Wendy Carolina Gomez Ramirez

181 Use of a Chagas Urine Nanoparticle Test (Chunap) to Correlate with Parasitemia Levels in T. cruzi/HIV Co-Infected Patients

Authors: Yagahira E. Castro-Sesquen, Robert H. Gilman, Carolina Mejia, Daniel E. Clark, Jeong Choi, Melissa J. Reimer-Mcatee, Rocio Castro, Jorge Flores, Edward Valencia-Ayala, Faustino Torrico, Ricardo Castillo-Neyra, Lance Liotta, Caryn Bern, Alessandra Luchini

Abstract:

Early diagnosis of reactivation of Chagas disease in HIV patients could be lifesaving; however, in Latin American the diagnosis is performed by detection of parasitemia by microscopy which lacks sensitivity. To evaluate if levels of T. cruzi antigens in urine determined by Chunap (Chagas urine nanoparticle test) are correlated with parasitemia levels in T. cruzi/HIV co-infected patients. T. cruzi antigens in urine of HIV patients (N=55: 31 T. cruzi infected and 24 T. cruzi serology negative) were concentrated using hydrogel particles and quantified by Western Blot and a calibration curve. The percentage of Chagas positive patients determined by Chunap compared to blood microscopy, qPCR, and ELISA was 100% (6/6), 95% (18/19) and 74% (23/31), respectively. Chunap specificity was 91.7%. Linear regression analysis demonstrated a direct relationship between parasitemia levels (determined by qPCR) and urine T. cruzi antigen concentrations (p<0.001). A cut-off of > 105 pg was chosen to determine patients with reactivation of Chagas disease (6/6). Urine antigen concentration was significantly higher among patients with CD4+ lymphocyte counts below 200/mL (p=0.045). Chunap shows potential for early detection of reactivation and with appropriate adaptation can be used for monitoring Chagas disease status in T. cruzi/HIV co-infected patients.

Keywords: antigenuria, Chagas disease, Chunap, nanoparticles, parasitemia, poly N-isopropylacrylamide (NIPAm)/trypan blue particles (polyNIPAm/TB), reactivation of Chagas disease.

Procedia PDF Downloads 350
180 Examining the Predicting Effect of Mindfulness on Psychological Well-Being among Undergraduate Students

Authors: Piyanee Klainin-Yobas, Debbie Ramirez, Zenaida Fernandez, Jenneth Sarmiento, Wareerat Thanoi, Jeanette Ignacio, Ying Lau

Abstract:

In many countries, university students experience various stressors that may negatively affect their psychological well-being (PWB). Hence, they are at risk for physical and mental problems. This research aimed to examine the predicting effects of mindfulness, self-efficacy, and social support on psychological well-being among undergraduate students. A non-experimental research was conducted at a university in the Philippines. All students enrolled in undergraduate programs were eligible for this study unless they had chronic medical or mental health problems. Power analysis was used to calculate an adequate sample size and a convenience sampling of 630 was recruited. Data were collected through online self-reported questionnaires from year 2013 to 2015. All self-reported scales used in this study had sound psychometric properties. Descriptive statistics, correlational analyses, and structural equation modeling were performed to analyze the research data. Results showed that the participants were mostly Filipino, female, Christian, and in Schools of Nursing. Mindfulness, self-efficacy, support from family, support from friends, and support from significant others were significant predictors of psychological well-being. Mindfulness was the strongest predictor of positive psychological well-being whereas self-efficacy was the strongest predictor of negative psychological well-being. In conclusion, findings from this study add knowledge to the existing literature regarding the predictors of psychological well-being. Psychosocial interventions, with the focus on strengthening mindfulness and self-efficacy, could be delivered to undergraduate students to help them enhance psychological well-being. More studies can be undertaken to test the interventions and multi-centered research can be conducted to enhance generalizability of research findings.

Keywords: mindfulness, self-efficacy, social support, psychological wellbeing

Procedia PDF Downloads 391
179 Closed Greenhouse Production Systems for Smart Plant Production in Urban Areas

Authors: U. Schmidt, D. Dannehl, I. Schuch, J. Suhl, T. Rocksch, R. Salazar-Moreno, E. Fitz-Rodrigues, A. Rojano Aquilar, I. Lopez Cruz, G. Navas Gomez, R. A. Abraham, L. C. Irineo, N. G. Gilberto

Abstract:

The integration of agricultural production systems into urban areas is a challenge for the coming decades. Because of increasing greenhouse gas emission and rising resource consumption as well as costs in animal husbandry, the dietary habits of people in the 21st century have to focus on herbal foods. Intensive plant cultivation systems in large cities and megacities require a smart coupling of information, material and energy flow with the urban infrastructure in terms of Horticulture 4.0. In recent years, many puzzle pieces have been developed for these closed processes at the Humboldt University. To compile these for an urban plant production, it has to be optimized and networked with urban infrastructure systems. In the field of heat energy production, it was shown that with closed greenhouse technology and patented heat exchange and storage technology energy can be provided for heating and domestic hot water supply in the city. Closed water circuits can be drastically reducing the water requirements of plant production in urban areas. Ion sensitive sensors and new disinfection methods can help keep circulating nutrient solutions in the system for a longer time in urban plant production greenhouses.

Keywords: semi closed, greenhouses, urban farming, solar heat collector, closed water cycles, aquaponics

Procedia PDF Downloads 305
178 Virtual Conciliation in Colombia: Evaluation of Maturity Level within the Framework of E-Government

Authors: Jenny Paola Forero Pachón, Sonia Cristina Gamboa Sarmiento, Luis Carlos Gómez Flórez

Abstract:

The Colombian government has defined an e-government strategy to take advantage of Information Technologies (IT) in order to contribute to the building of a more efficient, transparent and participative State that provides better services to citizens and businesses. In this regard, the Justice sector is one of the government sectors where IT has generated more expectation considering that the country has a judicial processes backlog. This situation has led to the search for alternative forms of access to justice that speed up the process while providing a low cost for citizens. To this end, the Colombian government has authorized the use of Alternative Dispute Resolution methods (ADR), a remedy where disputes can be resolved more quickly compared to judicial processes while facilitating greater communication between the parties, without recourse to judicial authority. One of these methods is conciliation, which includes a special modality that takes advantage of IT for the development of itself known as virtual conciliation. With this option the conciliation is supported by information systems, applications or platforms and communications are provided through it. This paper evaluates the level of maturity in how the service of virtual conciliation is under the framework of this strategy. This evaluation is carried out considering Shahkooh's 5-phase model for e-government. As a result, it is evident that in the context of conciliation, maturity does not reach the necessary level in the model so that it can be considered as virtual conciliation; therefore, it is necessary to define strategies to maximize the potential of IT in this context.

Keywords: alternative dispute resolution, e-government, evaluation of maturity, Shahkooh model, virtual conciliation

Procedia PDF Downloads 235
177 Hypervirulent Klebsiella Pneumoniae in a South African Tertiary Hospital – Clinical Profile, Genetic Determinants and Virulence in Caenorhabditis Elegans

Authors: Dingiswayo Likhona, Arko-Cobbah Emmanuel, Carolina Pohl, Nthabiseng Z. Mokoena, Jolly Musoke

Abstract:

A distinct strain of Klebsiella pneumoniae (K. pneumoniae), referred to as hypervirulent (hvKp), is associated with invasive infections such as an invasive pyogenic liver abscess in young and healthy individuals. In South Africa, limited information is known about the prevalence and virulence of this hvKp strain. Thus, this study aimed to determine the prevalence of hvKp and virulence-associated factors in K. pneumoniae isolates from one of the largest Tertiary hospitals in a South African province. A total of 74 K. pneumoniae isolates were received from Pelonomi National Health Laboratory Services (NHLS), Bloemfontein. Virulence-associated genes (rmpA, capsule serotype K1/K2, iroB, and irp2) were screened, and the virulence of hvKp vs. classical Klebsiella pneumoniae (cKp) was investigated using Caenorhabditis elegans nematode model. The iutA (aerobactin transporter) gene was used as a primary biomarker of hvKp. An average of 12% (9/74) of cases were defined as hvKp. Moreover, hvKp was found to be significantly more virulent in vivo Caenorhabditis elegans relative to cKp. The virulence-associated genes (rmpA, iroB, hmv phenotype, and capsule K1/K2) were significantly (p< 0.05) associated with hvKp. Findings from this study confirm the presence of hvKp in one large Tertiary hospital in South Africa. However, the low prevalence and mild to moderate clinical presentation suggest a marginal threat to public health. Further studies in different settings are required to establish the true potential impact of hvKp in developing countries.

Keywords: hypervirulent klebsiella pneumoniae, virulence, caenorhabditis elegans, aerobactin (iutA)

Procedia PDF Downloads 54
176 Performance Analysis of Search Medical Imaging Service on Cloud Storage Using Decision Trees

Authors: González A. Julio, Ramírez L. Leonardo, Puerta A. Gabriel

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Telemedicine services use a large amount of data, most of which are diagnostic images in Digital Imaging and Communications in Medicine (DICOM) and Health Level Seven (HL7) formats. Metadata is generated from each related image to support their identification. This study presents the use of decision trees for the optimization of information search processes for diagnostic images, hosted on the cloud server. To analyze the performance in the server, the following quality of service (QoS) metrics are evaluated: delay, bandwidth, jitter, latency and throughput in five test scenarios for a total of 26 experiments during the loading and downloading of DICOM images, hosted by the telemedicine group server of the Universidad Militar Nueva Granada, Bogotá, Colombia. By applying decision trees as a data mining technique and comparing it with the sequential search, it was possible to evaluate the search times of diagnostic images in the server. The results show that by using the metadata in decision trees, the search times are substantially improved, the computational resources are optimized and the request management of the telemedicine image service is improved. Based on the experiments carried out, search efficiency increased by 45% in relation to the sequential search, given that, when downloading a diagnostic image, false positives are avoided in management and acquisition processes of said information. It is concluded that, for the diagnostic images services in telemedicine, the technique of decision trees guarantees the accessibility and robustness in the acquisition and manipulation of medical images, in improvement of the diagnoses and medical procedures in patients.

Keywords: cloud storage, decision trees, diagnostic image, search, telemedicine

Procedia PDF Downloads 182
175 Correlations between Wear Rate and Energy Dissipation Mechanisms in a Ti6Al4V–WC/Co Sliding Pair

Authors: J. S. Rudas, J. M. Gutiérrez Cabeza, A. Corz Rodríguez, L. M. Gómez, A. O. Toro

Abstract:

The prediction of the wear rate of rubbing pairs has attracted the interest of many researchers for years. It has been recently proposed that the sliding wear rate can be inferred from the calculation of the energy rate dissipated by the tribological pair. In this paper some of the dissipative mechanisms present in a pin-on-disc configuration are discussed and both analytical and numerical calculations are carried out. Three dissipative mechanisms were studied: First, the energy release due to temperature gradients within the solid; second, the heat flow from the solid to the environment, and third, the energy loss due to abrasive damage of the surface. The Finite Element Method was used to calculate the dynamics of heat transfer within the solid, with the aid of commercial software. Validation the FEM model was assisted by virtual and laboratory experimentation using different operating points (sliding velocity and geometry contact). The materials for the experiments were Ti6Al4V alloy and Tungsten Carbide (WC-Co). The results showed that the sliding wear rate has a linear relationship with the energy dissipation flow. It was also found that energy loss due to micro-cutting is relevant for the system. This mechanism changes if the sliding velocity and pin geometry are modified though the degradation coefficient continues to present a linear behavior. We found that the less relevant dissipation mechanism for all the cases studied is the energy release by temperature gradients in the solid.

Keywords: degradation, dissipative mechanism, dry sliding, entropy, friction, wear

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174 Teenagers in Conflict with Law: Exploratory Study about Psychic Suffering

Authors: Carolina Alcântara, Ileno Costa

Abstract:

This study had the objective to systemize the main psycho-social and socioeducational aspects that related with the psychic suffering of adolescents in conflict of law and freedom privation. This research wanted to verify the signals and symptoms identified trough themselves perceptions related to their condition of health/insanity. In a similar way, it was objectified to know the opinions of the ambient conditions of the institution the use of the currently available resources for Health Service and Educational Service. The methodological proposal is based on the quant-qualitative analysis of interviews half-structuralized carried through with 36 teenagers was using psychiatric medication continuously. The data had pointed the experiences of sleeplessness and nightmares, associates or not with experiences of loss of reality (hallucinations) had constituted the illness most frequent. The self-punishment behavior appeared at second place. With regard to the ambient factors, it was verified that institution had, in general way, guaranteed the physical integrity and the maintenance of the health. Amongst the current available resources of Health Service, the administration of anticonvulsivants, in association with other psychotropic drugs has been widely used. The school was viewed as important device of available in the institution. By means of the adolescent’s understanding who do not like to go to the school, they don’t disqualify the knowledge, in contrast, they wanted for knowledge, however, they were frustrated for not having their educational supplies adequately, affirming that the school is weak or they do not learn. Finally, among the possible conclusions guided for the Winnicott’s thought, it was observed that institution in analysis is a representative of the paternal function. However, to begin the self-cure process is necessary that formation of therapeutical bonds. The group of teachers is identified as the main tool of change.

Keywords: serious psychic suffering, adolescent in conflict with the law, delinquency, privation of freedom

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173 Application of the Urban Forest Credit Standard as a Tool for Compensating CO2 Emissions in the Metalworking Industry: A Case Study in Brazil

Authors: Marie Madeleine Sarzi Inacio, Ligiane Carolina Leite Dauzacker, Rodrigo Henriques Lopes Da Silva

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The climate changes resulting from human activity have increased interest in more sustainable production practices to reduce and offset pollutant emissions. Brazil, with its vast areas capable of carbon absorption, holds a significant advantage in this context. However, to optimize the country's sustainable potential, it is important to establish a robust carbon market with clear rules for the eligibility and validation of projects aimed at reducing and offsetting Greenhouse Gas (GHG) emissions. In this study, our objective is to conduct a feasibility analysis through a case study to evaluate the implementation of an urban forest credits standard in Brazil, using the Urban Forest Credits (UFC) model implemented in the United States as a reference. Thus, the city of Ribeirão Preto, located in Brazil, was selected to assess the availability of green areas. With the CO2 emissions value from the metalworking industry, it was possible to analyze information in the case study, considering the activity. The QGIS software was used to map potential urban forest areas, which can connect to various types of geospatial databases. Although the chosen municipality has little vegetative coverage, the mapping identified at least eight areas that fit the standard definitions within the delimited urban perimeter. The outlook was positive, and the implementation of projects like Urban Forest Credits (UFC) adapted to the Brazilian reality has great potential to benefit the country in the carbon market and contribute to achieving its Greenhouse Gas (GHG) emission reduction goals.

Keywords: carbon neutrality, metalworking industry, carbon credits, urban forestry credits

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172 Mechanical Behavior of Recycled Mortars Manufactured from Moisture Correction Using the Halogen Light Thermogravimetric Balance as an Alternative to the Traditional ASTM C 128 Method

Authors: Diana Gomez-Cano, J. C. Ochoa-Botero, Roberto Bernal Correa, Yhan Paul Arias

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To obtain high mechanical performance, the fresh conditions of a mortar are decisive. Measuring the absorption of aggregates used in mortar mixes is a fundamental requirement for proper design of the mixes prior to their placement in construction sites. In this sense, absorption is a determining factor in the design of a mix because it conditions the amount of water, which in turn affects the water/cement ratio and the final porosity of the mortar. Thus, this work focuses on the mechanical behavior of recycled mortars manufactured from moisture correction using the Thermogravimetric Balancing Halogen Light (TBHL) technique in comparison with the traditional ASTM C 128 International Standard method. The advantages of using the TBHL technique are favorable in terms of reduced consumption of resources such as materials, energy, and time. The results show that in contrast to the ASTM C 128 method, the TBHL alternative technique allows obtaining a higher precision in the absorption values of recycled aggregates, which is reflected not only in a more efficient process in terms of sustainability in the characterization of construction materials but also in an effect on the mechanical performance of recycled mortars.

Keywords: alternative raw materials, halogen light, recycled mortar, resources optimization, water absorption

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171 Thermal Performance of an Air-Water Heat Exchanger (AWHE) Operating in Groundwater and Hot-Humid Climate

Authors: César Ramírez-Dolores, Jorge Wong-Loya, Jorge Andaverde, Caleb Becerra

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Low-depth geothermal energy can take advantage of the use of the subsoil as an air conditioning technique, being used as a passive system or coupled to an active cooling and/or heating system. This source of air conditioning is possible because at a depth less than 10 meters, the subsoil temperature is practically homogeneous and tends to be constant regardless of the climatic conditions on the surface. The effect of temperature fluctuations on the soil surface decreases as depth increases due to the thermal inertia of the soil, causing temperature stability; this effect presents several advantages in the context of sustainable energy use. In the present work, the thermal behavior of a horizontal Air-Water Heat Exchanger (AWHE) is evaluated, and the thermal effectiveness and temperature of the air at the outlet of the prototype immersed in groundwater is experimentally determined. The thermohydraulic aspects of the heat exchanger were evaluated using the Number of Transfer Units-Efficiency (NTU-ε) method under conditions of groundwater flow in a coastal region of sandy soil (southeastern Mexico) and air flow induced by a blower, the system was constructed of polyvinyl chloride (PVC) and sensors were placed in both the exchanger and the water to record temperature changes. The results of this study indicate that when the exchanger operates in groundwater, it shows high thermal gains allowing better heat transfer, therefore, it significantly reduces the air temperature at the outlet of the system, which increases the thermal effectiveness of the system in values > 80%, this passive technique is relevant for building cooling applications and could represent a significant development in terms of thermal comfort for hot locations in emerging economy countries.

Keywords: convection, earth, geothermal energy, thermal comfort

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170 Technology in the Calculation of People Health Level: Design of a Computational Tool

Authors: Sara Herrero Jaén, José María Santamaría García, María Lourdes Jiménez Rodríguez, Jorge Luis Gómez González, Adriana Cercas Duque, Alexandra González Aguna

Abstract:

Background: Health concept has evolved throughout history. The health level is determined by the own individual perception. It is a dynamic process over time so that you can see variations from one moment to the next. In this way, knowing the health of the patients you care for, will facilitate decision making in the treatment of care. Objective: To design a technological tool that calculates the people health level in a sequential way over time. Material and Methods: Deductive methodology through text analysis, extraction and logical knowledge formalization and education with expert group. Studying time: September 2015- actually. Results: A computational tool for the use of health personnel has been designed. It has 11 variables. Each variable can be given a value from 1 to 5, with 1 being the minimum value and 5 being the maximum value. By adding the result of the 11 variables we obtain a magnitude in a certain time, the health level of the person. The health calculator allows to represent people health level at a time, establishing temporal cuts being useful to determine the evolution of the individual over time. Conclusion: The Information and Communication Technologies (ICT) allow training and help in various disciplinary areas. It is important to highlight their relevance in the field of health. Based on the health formalization, care acts can be directed towards some of the propositional elements of the concept above. The care acts will modify the people health level. The health calculator allows the prioritization and prediction of different strategies of health care in hospital units.

Keywords: calculator, care, eHealth, health

Procedia PDF Downloads 237
169 Planning Quality and Maintenance Activities in a Closed-Loop Serial Multi-Stage Manufacturing System under Constant Degradation

Authors: Amauri Josafat Gomez Aguilar, Jean Pierre Kenné

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This research presents the development of a self-sustainable manufacturing system from a circular economy perspective, structured by a multi-stage serial production system consisting of a series of machines under deterioration in charge of producing a single product and a reverse remanufacturing system constituted by the same productive systems of the first scheme and different tooling, fed by-products collected at the end of their life cycle, and non-conforming elements of the first productive scheme. Since the advanced production manufacturing system is unable to satisfy the customer's quality expectations completely, we propose the development of a mixed integer linear mathematical model focused on the optimal search and assignment of quality stations and preventive maintenance operation to the machines over a time horizon, intending to segregate the correct number of non-conforming parts for reuse in the remanufacturing system and thereby minimizing production, quality, maintenance, and customer non-conformance penalties. Numerical experiments are performed to analyze the solutions found by the model under different scenarios. The results showed that the correct implementation of a closed manufacturing system and allocation of quality inspection and preventive maintenance operations generate better levels of customer satisfaction and an efficient manufacturing system.

Keywords: closed loop, mixed integer linear programming, preventive maintenance, quality inspection

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168 Removal of Diesel by Soil Washing Technologies Using a Non-Ionic Surfactant

Authors: Carolina Guatemala, Josefina Barrera

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A large number of soils highly polluted with recalcitrant hydrocarbons and the limitation of the current bioremediation methods continue being the drawback for an efficient recuperation of these under safe conditions. In this regard, soil washing by degradable surfactants is an alternative option knowing the capacity of surfactants to desorb oily organic compounds. The aim of this study was the establishment of the washing conditions of a soil polluted with diesel, using a nonionic surfactant. A soil polluted with diesel was used. This was collected near to a polluted railway station zone. The soil was dried at room temperature and sieved to a mesh size 10 for its physicochemical and biological characterization. Washing of the polluted soil was performed with surfactant solutions in a 1:5 ratio (5g of soil per 25 mL of the surfactant solution). This was carried out at 28±1 °C and 150 rpm for 72 hours. The factors tested were the Tween 80 surfactant concentration (1, 2, 5 and 10%) and the treatment time. Residual diesel concentration was determined every 24 h. The soil was of a sandy loam texture with a low concentration of organic matter (3.68%) and conductivity (0.016 dS.m- 1). The soil had a pH of 7.63 which was slightly alkaline and a Total Petroleum Hydrocarbon content (TPH) of 11,600 ± 1058.38 mg/kg. The high TPH content could explain the low microbial count of 1.1105 determined as UFC per gram of dried soil. Within the range of the surfactant concentration tested for washing the polluted soil under study, TPH removal increased proportionally with the surfactant concentration. 5080.8 ± 422.2 ppm (43.8 ± 3.64 %) was the maximal concentration of TPH removed after 72 h of contact with surfactant pollution at 10%. Despite the high percentage of hydrocarbons removed, it is assumed that a higher concentration of these could be removed if the washing process is extended or is carried out by stages. Soil washing through the use of surfactants as a desorbing agent was found to be a viable and effective technology for the rapid recovery of soils highly polluted with recalcitrant hydrocarbons.

Keywords: diesel, hydrocarbons, soil washing, tween 80

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167 Carbon Blacks: A Broad Type of Carbon Materials with Different Electrocatalytic Activity to Produce H₂O₂

Authors: Alvaro Ramírez, Martín Muñoz-Morales, Ester López- Fernández, Javier Llanos, C. Ania

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Carbon blacks are value-added materials typically produced through the incomplete combustion or thermal decomposition of hydrocarbons. Traditionally, they have been used as catalysts in many different applications, but in the last decade, their potential in green chemistry has gained significant attention. Among them, the electrochemical production of H₂O₂ has attracted interest because of their properties as high oxidant capacity or their industrial interest as a bleaching agent. Carbon blacks are commonly used in this application in a catalytic ink that is drop-casted on supporting electrodes and acts as catalysts for the electrochemical production of H₂O₂ through oxygen reduction reaction (ORR). However, the different structural and electrochemical behaviors of each type of carbon black influence their applications. In this line, the term ‘carbon black’, has to be considered as a generic name that does not guarantee any physicochemical properties if any further description is mentioned. In fact, different specific surface area (SSA), surface functional groups, porous structure, and electro catalysts effect seem very important for electrochemical applications, and considerable differences were found during the analysis of four types of carbon blacks. Thus, the aim of this work is to evaluate the influence of SSA, porous structure, oxygen functional groups, and structural defects to differentiate among these carbon blacks (e.g. Vulcan XC72, Superior Graphite Co, Printex XE2, and Prolabo) for H₂O₂ production via ORR, using carbon paper as electrode support with improved selectivity and efficiency. Results indicate that the number and size of pores, along with surface functional groups, are key parameters that significantly affect the overall process efficiency.

Keywords: carbon blacks, oxygen reduction reaction, hydrogen peroxide, porosity, surface functional groups

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166 Quantification and Identification of the Main Components of the Biomass of the Microalgae Scenedesmus SP. – Prospection of Molecules of Commercial Interest

Authors: Carolina V. Viegas, Monique Gonçalves, Gisel Chenard Diaz, Yordanka Reyes Cruz, Donato Alexandre Gomes Aranda

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To develop the massive cultivation of microalgae, it is necessary to isolate and characterize the species, improving genetic tools in search of specific characteristics. Therefore, the detection, identification and quantification of the compounds that compose the Scenedesmus sp. were prerequisites to verify the potential of these microalgae. The main objective of this work was to carry out the characterization of Scenedesmus sp. as to the content of ash, carbohydrates, proteins and lipids as well as the determination of the composition of their lipid classes and main fatty acids. The biomass of Scenedesmus sp, showed 15,29 ± 0,23 % of ash and CaO (36,17 %) was the main component of this fraction, The total protein and carbohydrate content of the biomass was 40,74 ± 1,01 % and 23,37 ± 0,95 %, respectively, proving to be a potential source of proteins as well as carbohydrates for the production of ethanol via fermentation, The lipid contents extracted via Bligh & Dyer and in situ saponification were 8,18 ± 0,13 % and 4,11 ± 0,11 %, respectively. In the lipid extracts obtained via Bligh & Dyer, approximately 50 % of the composition of this fraction consists of fatty compounds, while the other half is composed of an unsaponifiable fraction composed mainly of chlorophylls, phytosterols and carotenes. From the lowest yield, it was possible to obtain a selectivity of 92,14 % for fatty components (fatty acids and fatty esters) confirmed through the infrared spectroscopy technique. The presence of polyunsaturated acids (~45 %) in the lipid extracts indicated the potential of this fraction as a source of nutraceuticals. The results indicate that the biomass of Scenedesmus sp, can become a promising potential source for obtaining polyunsaturated fatty acids, carotenoids and proteins as well as the simultaneous obtainment of different compounds of high commercial value.

Keywords: microalgae, Desmodesmus, lipid classes, fatty acid profile, proteins, carbohydrates

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165 Open Innovation Laboratory for Rapid Realization of Sensing, Smart and Sustainable Products (S3 Products) for Higher Education

Authors: J. Miranda, D. Chavarría-Barrientos, M. Ramírez-Cadena, M. E. Macías, P. Ponce, J. Noguez, R. Pérez-Rodríguez, P. K. Wright, A. Molina

Abstract:

Higher education methods need to evolve because the new generations of students are learning in different ways. One way is by adopting emergent technologies, new learning methods and promoting the maker movement. As a result, Tecnologico de Monterrey is developing Open Innovation Laboratories as an immediate response to educational challenges of the world. This paper presents an Open Innovation Laboratory for Rapid Realization of Sensing, Smart and Sustainable Products (S3 Products). The Open Innovation Laboratory is composed of a set of specific resources where students and teachers use them to provide solutions to current problems of priority sectors through the development of a new generation of products. This new generation of products considers the concepts Sensing, Smart, and Sustainable. The Open Innovation Laboratory has been implemented in different courses in the context of New Product Development (NPD) and Integrated Manufacturing Systems (IMS) at Tecnologico de Monterrey. The implementation consists of adapting this Open Innovation Laboratory within the course’s syllabus in combination with the implementation of specific methodologies for product development, learning methods (Active Learning and Blended Learning using Massive Open Online Courses MOOCs) and rapid product realization platforms. Using the concepts proposed it is possible to demonstrate that students can propose innovative and sustainable products, and demonstrate how the learning process could be improved using technological resources applied in the higher educational sector. Finally, examples of innovative S3 products developed at Tecnologico de Monterrey are presented.

Keywords: active learning, blended learning, maker movement, new product development, open innovation laboratory

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164 Case Studies of Educational Technology Integration for Global Citizenship Development among Teacher Candidates

Authors: Erik Jon Byker

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Government leaders and education policymakers have increasingly focused on ways that teachers can better prepare children for life in a global society. Such preparation includes the development of global citizenship among young people. Yet, scholars point out that many elementary school educators and teacher candidates have limited awareness of being global citizens in an interdependent world. More and more teacher preparation programs aim to integrate global citizenship in their program plans and use educational technology to help develop global citizenship. Many non-governmental organizations (NGOs), like the Asia Society and Partnership for 21st Century Skills, have led the way in creating global citizenship frameworks that prepare teachers and students with global competencies. The development of global citizenship among teachers needs to begin even before teachers sign their first contract. Global citizenship development should start when teacher candidates are being prepared to teach. Using the Critical Cosmopolitan Theory as a conceptual lens, this paper examines the integration of global citizenship curricula in teacher education programs in North Carolina and Texas in the United States of America. Using a case study methodology, the paper describes and compares the teacher candidates’ (n=136) perceptions of the global citizenship curricula delivered with the aid of educational technology. The study found that after participating in the global citizenship curricula, participants: (1) made conceptual leaps in their global citizenship definitions; (2) developed a stronger commitment for their future role as educators in developing global citizens; and (3) were more willing to take action for social justice-related issues in education. In sum, this paper discusses empirical findings related to the ways to integrate educational technology in preparing globally competent teachers.

Keywords: educational technology, global education, intercultural awareness, teacher candidates

Procedia PDF Downloads 180
163 Comparing Energy Labelling of Buildings in Spain

Authors: Carolina Aparicio-Fernández, Alejandro Vilar Abad, Mar Cañada Soriano, Jose-Luis Vivancos

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The building sector is responsible for 40% of the total energy consumption in the European Union (EU). Thus, implementation of strategies for quantifying and reducing buildings energy consumption is indispensable for reaching the EU’s carbon neutrality and energy efficiency goals. Each Member State has transposed the European Directives according to its own peculiarities: existing technical legislation, constructive solutions, climatic zones, etc. Therefore, in accordance with the Energy Performance of Buildings Directive, Member States have developed different Energy Performance Certificate schemes, using proposed energy simulation software-tool for each national or regional area. Energy Performance Certificates provide a powerful and comprehensive information to predict, analyze and improve the energy demand of new and existing buildings. Energy simulation software and databases allow a better understanding of the current constructive reality of the European building stock. However, Energy Performance Certificates still have to face several issues to consider them as a reliable and global source of information since different calculation tools are used that do not allow the connection between them. In this document, TRNSYS (TRaNsient System Simulation program) software is used to calculate the energy demand of a building, and it is compared with the energy labeling obtained with Spanish Official software-tools. We demonstrate the possibility of using not official software-tools to calculate the Energy Performance Certificate. Thus, this approach could be used throughout the EU and compare the results in all possible cases proposed by the EU Member States. To implement the simulations, an isolated single-family house with different construction solutions is considered. The results are obtained for every climatic zone of the Spanish Technical Building Code.

Keywords: energy demand, energy performance certificate EPBD, trnsys, buildings

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162 Rescaled Range Analysis of Seismic Time-Series: Example of the Recent Seismic Crisis of Alhoceima

Authors: Marina Benito-Parejo, Raul Perez-Lopez, Miguel Herraiz, Carolina Guardiola-Albert, Cesar Martinez

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Persistency, long-term memory and randomness are intrinsic properties of time-series of earthquakes. The Rescaled Range Analysis (RS-Analysis) was introduced by Hurst in 1956 and modified by Mandelbrot and Wallis in 1964. This method represents a simple and elegant analysis which determines the range of variation of one natural property (the seismic energy released in this case) in a time interval. Despite the simplicity, there is complexity inherent in the property measured. The cumulative curve of the energy released in time is the well-known fractal geometry of a devil’s staircase. This geometry is used for determining the maximum and minimum value of the range, which is normalized by the standard deviation. The rescaled range obtained obeys a power-law with the time, and the exponent is the Hurst value. Depending on this value, time-series can be classified in long-term or short-term memory. Hence, an algorithm has been developed for compiling the RS-Analysis for time series of earthquakes by days. Completeness time distribution and locally stationarity of the time series are required. The interest of this analysis is their application for a complex seismic crisis where different earthquakes take place in clusters in a short period. Therefore, the Hurst exponent has been obtained for the seismic crisis of Alhoceima (Mediterranean Sea) of January-March, 2016, where at least five medium-sized earthquakes were triggered. According to the values obtained from the Hurst exponent for each cluster, a different mechanical origin can be detected, corroborated by the focal mechanisms calculated by the official institutions. Therefore, this type of analysis not only allows an approach to a greater understanding of a seismic series but also makes possible to discern different types of seismic origins.

Keywords: Alhoceima crisis, earthquake time series, Hurst exponent, rescaled range analysis

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161 Optimal Design of Tuned Inerter Damper-Based System for the Control of Wind-Induced Vibration in Tall Buildings through Cultural Algorithm

Authors: Luis Lara-Valencia, Mateo Ramirez-Acevedo, Daniel Caicedo, Jose Brito, Yosef Farbiarz

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Controlling wind-induced vibrations as well as aerodynamic forces, is an essential part of the structural design of tall buildings in order to guarantee the serviceability limit state of the structure. This paper presents a numerical investigation on the optimal design parameters of a Tuned Inerter Damper (TID) based system for the control of wind-induced vibration in tall buildings. The control system is based on the conventional TID, with the main difference that its location is changed from the ground level to the last two story-levels of the structural system. The TID tuning procedure is based on an evolutionary cultural algorithm in which the optimum design variables defined as the frequency and damping ratios were searched according to the optimization criteria of minimizing the root mean square (RMS) response of displacements at the nth story of the structure. A Monte Carlo simulation was used to represent the dynamic action of the wind in the time domain in which a time-series derived from the Davenport spectrum using eleven harmonic functions with randomly chosen phase angles was reproduced. The above-mentioned methodology was applied on a case-study derived from a 37-story prestressed concrete building with 144 m height, in which the wind action overcomes the seismic action. The results showed that the optimally tuned TID is effective to reduce the RMS response of displacements up to 25%, which demonstrates the feasibility of the system for the control of wind-induced vibrations in tall buildings.

Keywords: evolutionary cultural algorithm, Monte Carlo simulation, tuned inerter damper, wind-induced vibrations

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160 Level of Understanding of the Catholic Doctrines in Relation to the Way of Life of Ignatian Graduates

Authors: Maria Wendy Mendoza-Solomo

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The study assessed the level of understanding of catholic doctrines in relation to the way of life of Ignatian graduates of Ateneo de Naga University (ADNU). It was conducted to find out if ADNU is successful in leading their students to a deeper moral understanding of the world centered on Jesus Christ through their curriculum, academic programs, activities and practices. This study further evaluated if their graduates live out their Catholic commitment to Christ in their current way of life. It also determined the factors that affected their level of understanding of Catholic doctrines and their current way of life. The descriptive, qualitative, evaluative and correlational analyses determined the level of understanding of the Catholic doctrines and the current way of life of 390 graduates. It also correlated the level of understanding to moral life and worship. The factors that affected the graduates’ level of understanding and their current way of life were measured. A researcher-made instrument was distributed to the respondents either using the traditional way or the online survey to reach out graduates across the globe. Major findings were (1) The weighted mean of graduates’ level of understanding of Catholic doctrines was 4.63. (2) Along moral life, 4.07 while along worship, 3.83. (3) The Catholic doctrines and moral life had Pearson r value of 0.79. The doctrines and worship, 0.87; and worship and moral life, 0.89. (4) The understanding of the doctrines was affected highly by the teacher factor with 4.09 mean. The moral life and worship were affected highly by the teacher and technological factors both ranked 1.5 (4.04). (5) Along Catholic doctrines, the teacher factor had 0.90 r value; and environmental, -0.40. Along moral life, teacher had r value of -0.30; technological (-0.92), socio-economic (-0.93), political (-0.83), and environmental (-0.90). Along worship, the teacher had 0.36 Pearson r value, technological and socio-economic (-0.78), political (-0.73) and environmental (-0.72). Major conclusions were: (1) Graduates had very high level of understanding of the Catholic doctrines as summarized in the Creed which is grounded in the Sacred Scriptures. (2) They live out this Catholic commitment to Christ by obeying the Commandments very extensively but needed more participation in religious and parish activities. They have overwhelming spirituality and religiosity in terms of receiving of sacraments and sacramental practices except reading the Bible and reflecting on its passages. (3) The graduates’ level of understanding of the Catholic doctrines had very strong correlation with their current way of life. (4) Teacher, socio-economic, technological, environmental, and political factors significantly affected their understanding of the Catholic doctrines and their current way of life. (5) The teacher factor had very strong relationship with the doctrines; technological and political, weak; environmental, moderate; and socio-economic, very weak relationship. The teacher factor had weak relationship but the other factors had very strong relationship with moral life and strong relationship with worship.

Keywords: Catholic doctrines, Ignatian graduates, relationship, way of life

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159 Hallucinatory Activity in Schizophrenia: The Relationship with Childhood Memories, Submissive Behavior, Social Comparison, and Depression

Authors: Célia Barreto Carvalho, Carolina da Motta, José Pinto-Gouveia, Ermelindo Bernardo Peixoto

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Auditory hallucinations among the most invalidating and distressing experiences reported by patients diagnosed with schizophrenia, leading to feelings of powerlessness and helplessness towards their illness. In more severe cases, these auditory hallucinations can take the form of commanding voices, which are often related to high suicidality rates in these patients. Several authors propose that the meanings attributed to the hallucinatory experience, rather than characteristics like form and content, can be determinant in patients’ reactions to hallucinatory activity, particularly in the case of voice-hearing experiences. In this study, 48 patients diagnosed with paranoid schizophrenia presenting auditory hallucinations were studied. Multiple regression analyses were computed to study the influence of several developmental aspects, such as family and social dynamics, bullying, depression, and socio-cognitive variables on the auditory hallucinations, on patients’ attributions and relationships with their voices, and on the resulting invalidation of hallucinatory experience. Overall, results showed how relationships with voices can mirror several aspects of interpersonal relationship with others, and how self-schemas, depression and actual social relationships help shaping the voice-hearing experience. Early experiences of victimization and submission help predict the attributions of omnipotence of the voices, and increased hostility from parents seems to increase the malevolence of the voices, suggesting that socio-cognitive factors can significantly contribute to the etiology and maintenance of auditory hallucinations. The understanding of the characteristics of auditory hallucinations and the relationships patients established with their voices can allow the development of more promising therapeutic interventions that can be more effective in decreasing invalidation caused by this devastating mental illness.

Keywords: auditory hallucination, beliefs, life events, schizophrenia

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158 Post-Anesthetic Recovery: The Best Moment to Apply Positive Pressure in Airway in Postoperative Bariatric Surgery

Authors: Eli Maria Pazzianotto-Forti, Patrícia Brigatto, Letícia Baltieri, Carolina Moraes Da Costa, Maura Rigoldi Simoes Da Rocha, Irineu Rasera Jr

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The application of positive pressure in airway can contribute to the restoration of lung volumes, capacities and prevent respiratory complications. The aim was to investigate the use of Bilevel Positive Airway Pressure (BIPAP) in morbidly obese in two moments in postoperative bariatric surgery: In the post-anesthetic recovery (PAR) and on the 1st postoperative day (1stPO). Twenty morbidly obese, aged between 25 and 55 years, underwent pulmonary function test and chest X-ray preoperatively and on the day of discharge (2nd day after surgery). They were randomly allocated in groups. GPAR: received BIPAP treatment in PAR, for an hour and G1stPO: received BIPAP for one hour, on the 1stPO. There were significant reductions in slow vital capacity (SVC) (p=0.0007), inspiratory reserve volume (IRV) (p=0.0016) and forced vital capacity (FVC) (p=0.0013) in the postoperative in GPAR and the expiratory reserve volume (ERV) remained (p=0.4446). In the G1stPO, there were significant reductions for: SVC p=<0.0001, ERV p=0.0191, IRV p= 0.0026 and FVC p=<0.0001. Comparing between groups, the SVC (p=0.0027) and FVC (p=0.0028) showed significant difference between the treatments. However, the GPAR showed fewer declines of these capacities. To the ERV (p= 0.1646) and IRV (p=0.3973) there was no significant difference between groups. The atelectasis prevalence was 10% for the GPAR and 30% for G1stPO, with significant difference between the proportions (p = 0.0027). The lowest reduction in SVC and FVC happens when positive pressure is applied in PAR. Thus, the use of BIPAP in the PAR can promote a restoration of ERV and contribute to the reduction of atelectasis. FAPESP 2013/06334-8.

Keywords: atelectasis, bariatric surgery, physiotherapy, pulmonary function, positive pressure

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157 Use of the Occupational Repetitive Action Method in Different Productive Sectors: A Literature Review 2007-2018

Authors: Aanh Eduardo Dimate-Garcia, Diana Carolina Rodriguez-Romero, Edna Yuliana Gonzalez Rincon, Diana Marcela Pardo Lopez, Yessica Garibello Cubillos

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Musculoskeletal disorders (MD) are the new epidemic of chronic diseases, are multifactorial and affect the different productive sectors. Although there are multiple instruments to evaluate the static and dynamic load, the method of repetitive occupational action (OCRA) seems to be an attractive option. Objective: It is aimed to analyze the use of the OCRA method and the prevalence of MD in workers of various productive sectors according to the literature (2007-2018). Materials and Methods: A literature review (following the PRISMA statement) of studies aimed at assessing the level of biomechanical risk (OCRA) and the prevalence of MD in the databases Scielo, Science Direct, Scopus, ProQuest, Gale, PubMed, Lilacs and Ebsco was realized; 7 studies met the selection criteria; the majority are quantitative (cross section). Results: it was evidenced (gardening and flower-growers) in this review that 79% of the conditions related to the task require physical requirements and involve repetitive movements. In addition, of the high appearance of DM in the high-low back, upper and lower extremities that are produced by the frequency of the activities carried out (footwear production). Likewise, there was evidence of 'very high risks' of developing MD (salmon industry) and a medium index (OCRA) for repetitive movements that require special care (U-Assembly line). Conclusions: the review showed the limited use of the OCRA method for the detection of MD in workers from different sectors, and this method can be used for the detection of biomechanical risk and the appearance of MD.

Keywords: checklist, cumulative trauma disorders, musculoskeletal diseases, repetitive movements

Procedia PDF Downloads 155
156 A Multi-Objective Decision Making Model for Biodiversity Conservation and Planning: Exploring the Concept of Interdependency

Authors: M. Mohan, J. P. Roise, G. P. Catts

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Despite living in an era where conservation zones are de-facto the central element in any sustainable wildlife management strategy, we still find ourselves grappling with several pareto-optimal situations regarding resource allocation and area distribution for the same. In this paper, a multi-objective decision making (MODM) model is presented to answer the question of whether or not we can establish mutual relationships between these contradicting objectives. For our study, we considered a Red-cockaded woodpecker (Picoides borealis) habitat conservation scenario in the coastal plain of North Carolina, USA. Red-cockaded woodpecker (RCW) is a non-migratory territorial bird that excavates cavities in living pine trees for roosting and nesting. The RCW groups nest in an aggregation of cavity trees called ‘cluster’ and for our model we use the number of clusters to be established as a measure of evaluating the size of conservation zone required. The case study is formulated as a linear programming problem and the objective function optimises the Red-cockaded woodpecker clusters, carbon retention rate, biofuel, public safety and Net Present Value (NPV) of the forest. We studied the variation of individual objectives with respect to the amount of area available and plotted a two dimensional dynamic graph after establishing interrelations between the objectives. We further explore the concept of interdependency by integrating the MODM model with GIS, and derive a raster file representing carbon distribution from the existing forest dataset. Model results demonstrate the applicability of interdependency from both linear and spatial perspectives, and suggest that this approach holds immense potential for enhancing environmental investment decision making in future.

Keywords: conservation, interdependency, multi-objective decision making, red-cockaded woodpecker

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155 Application of Finite Volume Method for Numerical Simulation of Contaminant Transfer in a Two-Dimensional Reservoir

Authors: Atousa Ataieyan, Salvador A. Gomez-Lopera, Gennaro Sepede

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Today, due to the growing urban population and consequently, the increasing water demand in cities, the amount of contaminants entering the water resources is increasing. This can impose harmful effects on the quality of the downstream water. Therefore, predicting the concentration of discharged pollutants at different times and distances of the interested area is of high importance in order to carry out preventative and controlling measures, as well as to avoid consuming the contaminated water. In this paper, the concentration distribution of an injected conservative pollutant in a square reservoir containing four symmetric blocks and three sources using Finite Volume Method (FVM) is simulated. For this purpose, after estimating the flow velocity, classical Advection-Diffusion Equation (ADE) has been discretized over the studying domain by Backward Time- Backward Space (BTBS) scheme. Then, the discretized equations for each node have been derived according to the initial condition, boundary conditions and point contaminant sources. Finally, taking into account the appropriate time step and space step, a computational code was set up in MATLAB. Contaminant concentration was then obtained at different times and distances. Simulation results show how using BTBS differentiating scheme and FVM as a numerical method for solving the partial differential equation of transport is an appropriate approach in the case of two-dimensional contaminant transfer in an advective-diffusive flow.

Keywords: BTBS differentiating scheme, contaminant concentration, finite volume, mass transfer, water pollution

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154 Study of the Polymer Elastic Behavior in the Displacement Oil Drops at Pore Scale

Authors: Luis Prada, Jose Gomez, Arlex Chaves, Julio Pedraza

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Polymeric liquids have been used in the oil industry, especially at enhanced oil recovery (EOR). From the rheological point of view, polymers have the particularity of being viscoelastic liquids. One of the most common and useful models to describe that behavior is the Upper Convected Maxwell model (UCM). The main characteristic of the polymer used in EOR process is the increase in viscosity which pushes the oil outside of the reservoir. The elasticity could contribute in the drag of the oil that stays in the reservoir. Studying the elastic effect on the oil drop at the pore scale, bring an explanation if the addition of elastic force could mobilize the oil. This research explores if the contraction and expansion of the polymer in the pore scale may increase the elastic behavior of this kind of fluid. For that reason, this work simplified the pore geometry and build two simple geometries with micrometer lengths. Using source terms with the user define a function this work introduces the UCM model in the ANSYS fluent simulator with the purpose of evaluating the elastic effect of the polymer in a contraction and expansion geometry. Also, using the Eulerian multiphase model, this research considers the possibility that extra elastic force will show a deformation effect on the oil; for that reason, this work considers an oil drop on the upper wall of the geometry. Finally, all the simulations exhibit that at the pore scale conditions exist extra vortices at UCM model but is not possible to deform the oil completely and push it outside of the restrictions, also this research find the conditions for the oil displacement.

Keywords: ANSYS fluent, interfacial fluids mechanics, polymers, pore scale, viscoelasticity

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153 Molecular Engineering of Intrinsically Microporous Polybenzimidazole for Energy-efficient Gas Separation

Authors: Mahmoud Abdulhamid, Rifan Hardian, Prashant Bhatt, Shuvo Datta, Adrian Ramirez, Jorge Gascon, Mohamed Eddaoudi, Gyorgy Szekely

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Polybenzimidazole (PBI) is a high-performance polymer that exhibits high thermal and chemical stability. However, it suffers from low porosity and low fractional free volume, which hinder its application as separation material. Herein, we demonstrate the molecular engineering of gas separation materials by manipulating a PBI backbone possessing kinked moieties. PBI was selected as it contains NH groups which increase the affinity towards CO₂, increase sorption capacity, and favors CO₂ over other gasses. We have designed and synthesized an intrinsically microporous polybenzimidazole (iPBI) featuring a spirobisindane structure. Introducing a kinked moiety in conjunction with crosslinking enhanced the polymer properties, markedly increasing the gas separation performance. In particular, the BET surface area of PBI increased 30-fold by replacing a flat benzene ring with a kinked structure. iPBI displayed a good CO₂ uptake of 1.4 mmol g⁻¹ at 1 bar and 3.6 mmol g⁻¹ at 10 bar. Gas sorption uptake and breakthrough experiments were conducted using mixtures of CO₂/CH₄ (50%/50%) and CO₂/N₂ (50%/50%), which revealed the high selectivity of CO₂ over both CH₄ and N₂. The obtained CO₂/N₂ selectivity is attractive for power plant flue gas application requiring CO₂ capturing materials. Energy and process simulations of biogas CO₂ removal demonstrated that up to 70% of the capture energy could be saved when iPBI was used rather than the current amine technology (methyl diethanolamine [MDEA]). Similarly, the combination of iPBI and MDEA in a hybrid system exhibited the highest CO₂ capture yield (99%), resulting in nearly 50% energy saving. The concept of enhancing the porosity of PBI using kinked moieties provides new scope for designing highly porous polybenzimidazoles for various separation processes.

Keywords: polybenzimidazole (PBI), intrinsically microporous polybenzimidazole (iPBI), gas separation, pnergy and process simulations

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152 Modelling of Damage as Hinges in Segmented Tunnels

Authors: Gelacio JuáRez-Luna, Daniel Enrique GonzáLez-RamíRez, Enrique Tenorio-Montero

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Frame elements coupled with springs elements are used for modelling the development of hinges in segmented tunnels, the spring elements modelled the rotational, transversal and axial failure. These spring elements are equipped with constitutive models to include independently the moment, shear force and axial force, respectively. These constitutive models are formulated based on damage mechanics and experimental test reported in the literature review. The mesh of the segmented tunnels was discretized in the software GID, and the nonlinear analyses were carried out in the finite element software ANSYS. These analyses provide the capacity curve of the primary and secondary lining of a segmented tunnel. Two numerical examples of segmented tunnels show the capability of the spring elements to release energy by the development of hinges. The first example is a segmental concrete lining discretized with frame elements loaded until hinges occurred in the lining. The second example is a tunnel with primary and secondary lining, discretized with a double ring frame model. The outer ring simulates the segmental concrete lining and the inner ring simulates the secondary cast-in-place concrete lining. Spring elements also modelled the joints between the segments in the circumferential direction and the ring joints, which connect parallel adjacent rings. The computed load vs displacement curves are congruent with numerical and experimental results reported in the literature review. It is shown that the modelling of a tunnel with primary and secondary lining with frame elements and springs provides reasonable results and save computational cost, comparing with 2D or 3D models equipped with smeared crack models.

Keywords: damage, hinges, lining, tunnel

Procedia PDF Downloads 367