Search results for: Carlos Muñoz Hernández
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 593

Search results for: Carlos Muñoz Hernández

593 A Petri Net Model to Obtain the Throughput of Unreliable Production Lines in the Buffer Allocation Problem

Authors: Joselito Medina-Marin, Alexandr Karelin, Ana Tarasenko, Juan Carlos Seck-Tuoh-Mora, Norberto Hernandez-Romero, Eva Selene Hernandez-Gress

Abstract:

A production line designer faces with several challenges in manufacturing system design. One of them is the assignment of buffer slots in between every machine of the production line in order to maximize the throughput of the whole line, which is known as the Buffer Allocation Problem (BAP). The BAP is a combinatorial problem that depends on the number of machines and the total number of slots to be distributed on the production line. In this paper, we are proposing a Petri Net (PN) Model to obtain the throughput in unreliable production lines, based on PN mathematical tools and the decomposition method. The results obtained by this methodology are similar to those presented in previous works, and the number of machines is not a hard restriction.

Keywords: buffer allocation problem, Petri Nets, throughput, production lines

Procedia PDF Downloads 277
592 Implementation of a Serializer to Represent PHP Objects in the Extensible Markup Language

Authors: Lidia N. Hernández-Piña, Carlos R. Jaimez-González

Abstract:

Interoperability in distributed systems is an important feature that refers to the communication of two applications written in different programming languages. This paper presents a serializer and a de-serializer of PHP objects to and from XML, which is an independent library written in the PHP programming language. The XML generated by this serializer is independent of the programming language, and can be used by other existing Web Objects in XML (WOX) serializers and de-serializers, which allow interoperability with other object-oriented programming languages.

Keywords: interoperability, PHP object serialization, PHP to XML, web objects in XML, WOX

Procedia PDF Downloads 205
591 Cognitive Footprints: Analytical and Predictive Paradigm for Digital Learning

Authors: Marina Vicario, Amadeo Argüelles, Pilar Gómez, Carlos Hernández

Abstract:

In this paper, the Computer Research Network of the National Polytechnic Institute of Mexico proposes a paradigmatic model for the inference of cognitive patterns in digital learning systems. This model leads to metadata architecture useful for analysis and prediction in online learning systems; especially on MOOc's architectures. The model is in the design phase and expects to be tested through an institutional of courses project which is going to develop for the MOOc.

Keywords: cognitive footprints, learning analytics, predictive learning, digital learning, educational computing, educational informatics

Procedia PDF Downloads 435
590 Comparison of the Results of a Parkinson’s Holter Monitor with Patient Diaries, in Real Conditions of Use: A Sub-Analysis of the MoMoPa-EC Clinical Trial

Authors: Alejandro Rodríguez-Molinero, Carlos Pérez-López, Jorge Hernández-Vara, Àngels Bayes-Rusiñol, Juan Carlos Martínez-Castrillo, David A. Pérez-Martínez

Abstract:

Background: Monitoring motor symptoms in Parkinson's patients is often a complex and time-consuming task for clinicians, as Hauser's diaries are often poorly completed by patients. Recently, new automatic devices (Parkinson's holter: STAT-ON®) have been developed capable of monitoring patients' motor fluctuations. The MoMoPa-EC clinical trial (NCT04176302) investigates which of the two methods produces better clinical results. In this sub-analysis, the concordance between both methods is analyzed. Methods: In the MoMoPa-EC clinical trial, 164 patients with moderate-severe Parkinson's disease and at least two hours a day of Off will be included. At the time of patient recruitment, all of them completed a seven-day motor fluctuation diary at home (Hauser’s diary) while wearing the Parkinson's holter. In this sub-analysis, 71 patients with complete data for the purpose of this comparison were included. The intraclass correlation coefficient was calculated between the patient diary entries and the Parkinson's holter data in terms of time On, Off, and time with dyskinesias. Results: The intra-class correlation coefficient of both methods was 0.57 (95% CI: 0.3-0.74) for daily time in Off (%), 0.48 (95% CI: 0.14-0.68) for daily time in On (%), and 0.37 (95% CI %: -0.04-0.62) for daily time with dyskinesias (%). Conclusions: Both methods have a moderate agreement with each other. We will have to wait for the results of the MoMoPa-EC project to estimate which of them has the greatest clinical benefits. Acknowledgment: This work is supported by AbbVie S.L.U, the Instituto de Salud Carlos III [DTS17/00195], and the European Fund for Regional Development, 'A way to make Europe'.

Keywords: Parkinson, sensor, motor fluctuations, dyskinesia

Procedia PDF Downloads 198
589 Design and Construction of Temperature and Humidity Control Channel for a Bacteriological Incubator

Authors: Carlos R. Duharte Rodríguez, Ibrain Ceballo Acosta, Carmen B. Busoch Morlán, Angel Regueiro Gómez, Annet Martinez Hernández

Abstract:

This work shows the designing and characterization of a prototype of laboratory incubator as support of research in Microbiology, in particular during studies of bacterial growth in biological samples, with the help of optic methods (Turbidimetry) and electrometric measurements of bioimpedance. It shows the results of simulation and experimentation of the design proposed for the canals of measurement of the variables: temperature and humidity, with a high linearity from the adequate selection of sensors and analogue components of every channel, controlled with help of a microcontroller AT89C51 (ATMEL) with adequate benefits for this type of application.

Keywords: microbiology, bacterial growth, incubation station, microorganisms

Procedia PDF Downloads 371
588 Educational Innovation and ICT: Before and during 21st Century

Authors: Carlos Monge López, Patricia Gómez Hernández

Abstract:

Educational innovation is a quality factor of teaching-learning processes and institutional accreditation. There is an increasing of these change processes, especially after 2000. However, the publications about this topic are more associated with ICTs in currently century. The main aim of the study was to determine the tendency of educational innovations around ICTs. The used method was mixed research design (content analysis, review of scientific literature and descriptive, comparative and correlation study) with 649 papers. In summary, the results indicated that, progressively, the educational innovation is associated with ICTs, in comparison with this type of change processes without ICTs. In conclusion, although this tendency, scientific literature must divulgate more kinds of pedagogical innovation with the aim of deepening in other new resources.

Keywords: descriptive study, knowledge society, pedagogical innovation, technologies

Procedia PDF Downloads 455
587 Predictive Maintenance Based on Oil Analysis Applicable to Transportation Fleets

Authors: Israel Ibarra Solis, Juan Carlos Rodriguez Sierra, Ma. del Carmen Salazar Hernandez, Isis Rodriguez Sanchez, David Perez Guerrero

Abstract:

At the present paper we try to explain the analysis techniques use for the lubricating oil in a maintenance period of a city bus (Mercedes Benz Boxer 40), which is call ‘R-24 route’, line Coecillo Centro SA de CV in Leon Guanajuato, to estimate the optimal time for the oil change. Using devices such as the rotational viscometer and the atomic absorption spectrometer, they can detect the incipient form when the oil loses its lubricating properties and, therefore, cannot protect the mechanical components of diesel engines such these trucks. Timely detection of lost property in the oil, it allows us taking preventive plan maintenance for the fleet.

Keywords: atomic absorption spectrometry, maintenance, predictive velocity rate, lubricating oils

Procedia PDF Downloads 533
586 A Model Approach of Good Practice Based on the Project Management Body of Knowledge® Guide in the Project Owner

Authors: Claudia Marcela Munoz Gonzalez, Diego Fernando Hernandez Losada, Hugo Alberto Herrera Fonseca

Abstract:

The project owner's role in the public-private investment consists of controlling and verifying the correct execution of the project's objectives and resources. Likewise, it is a discipline little explored in the academic field, whereby this work wishes to contribute with a model of good practices based on the project management methodology proposed by the Project Management Body of Knowledge® Guide. In the same way, highlight what are the controls that an integral project owner should take into account in its exercise and application, through the stages in which its contract runs. This proposal aims to structure its practice and integrate its functions according to a project management methodology. In addition, these practices will be applied in a case study of projects in the agricultural sector, particularly in the construction of irrigation district in Cundinamarca, Colombia.

Keywords: controls, construction of irrigation district, PMBOK®, project owner

Procedia PDF Downloads 425
585 Low-Cost VoIP University Solution

Authors: Carlos Henrique Rodrigues de Oliveira, Luis Carlos Costa Fonseca, Caio de Castro Torres, Daniel Gusmão Pereira, Luiz Ricardo Souza Ripardo, Magno Castro Moraes, Ana Paula Ferreira Costa, Luiz Carlos Chaves Lima Junior, Aurelianny Almeida da Cunha

Abstract:

VoIP University is a communication solution based on the IP protocol. This solution was proposed to modernize and save on communication, which required the development of Android, iOS, and Windows applications and a web service server. This solution allows integration with management system databases to create and manage a list of user extensions. VoIP University was deployed in a university, and a financial analysis revealed that annual spending on telephone bills decreased by more than 97 %.

Keywords: VoIP eTec, VoIP UEMA, VoIP University, VoIP Valen

Procedia PDF Downloads 15
584 A State-Of-The-Art Review on Web Services Adaptation

Authors: M. Velasco, D. While, P. Raju, J. Krasniewicz, A. Amini, L. Hernandez-Munoz

Abstract:

Web service adaptation involves the creation of adapters that solve Web services incompatibilities known as mismatches. Since the importance of Web services adaptation is increasing because of the frequent implementation and use of online Web services, this paper presents a literature review of web services to investigate the main methods of adaptation, their theoretical underpinnings and the metrics used to measure adapters performance. Eighteen publications were reviewed independently by two researchers. We found that adaptation techniques are needed to solve different types of problems that may arise due to incompatibilities in Web service interfaces, including protocols, messages, data and semantics that affect the interoperability of the services. Although adapters are non-invasive methods that can improve Web services interoperability and there are current approaches for service adaptation; there is, however, not yet one solution that fits all types of mismatches. Our results also show that only a few research projects incorporate theoretical frameworks and that metrics to measure adapters’ performance are very limited. We conclude that further research on software adaptation should improve current adaptation methods in different layers of the service interoperability and that an adaptation theoretical framework that incorporates a theoretical underpinning and measures of qualitative and quantitative performance needs to be created.

Keywords: Web Services Adapters, software adaptation, web services mismatches, web services interoperability

Procedia PDF Downloads 258
583 Coping Strategies of Female English Teachers and Housewives to Face the Challenges Associated to the COVID-19 Pandemic Lockdown

Authors: Lisseth Rojas Barreto, Carlos Muñoz Hernández

Abstract:

The COVID-19 pandemic led to many abrupt changes, including a prolonged lockdown, which brought about work and personal challenges to the population worldwide. Among the most affected populations are women who are workers and housewives at the same time, and especially those who are also parenting. These women were faced with the challenge to perform their usual varied roles during the lockdown from the same physical space, which inevitably had strong repercussions for each of them. This paper will present some results of a research study whose main objective was to examine the possible effects that the COVID-19 pandemic lockdown may have caused in the work, social, family, and personal environments of female English teachers who are also housewives and, by extension in the teaching and learning processes that they lead. Participants included five female English language teachers of a public foreign language school, they are all married, and two of them have children. Similarly, we examined some of the coping strategies these teachers used to tackle the pandemic-related challenges in their different roles, especially those used for their language teaching role; coping strategies are understood as a repertoire of behaviors in response to incidents that can be stressful for the subject, possible challenging events or situations that involve emotions with behaviors and decision-making of people which are used in order to find a meaning or positive result (Lazarus &Folkman, 1986) Following a qualitative-case study design, we gathered the data through a survey and a focus group interview with the participant teachers who work at a public language school in southern Colombia. Preliminary findings indicate that the circumstances that emerged as a result of the pandemic lockdown affected the participants in different ways, including financial, personal, family, health, and work-related issues. Among the strategies that participants found valuable to deal with the novel circumstances, we can highlight the reorganization of the household and work tasks and the increased awareness of time management for the household, work, and leisure. Additionally, we were able to evidence that the participants faced the circumstances with a positive view. Finally, in order to cope with their teaching duties, some participants acknowledged their lack of computer or technology literacy in order to deliver their classes online, which made them find support from their students or more knowledgeable peers to cope with it. Others indicated that they used strategies such as self-learning in order to get acquainted and be able to use the different technological tools and web-based platforms available.

Keywords: coping strategies, language teaching, female teachers, pandemic lockdown

Procedia PDF Downloads 77
582 Modeling and Simulation of Flow Shop Scheduling Problem through Petri Net Tools

Authors: Joselito Medina Marin, Norberto Hernández Romero, Juan Carlos Seck Tuoh Mora, Erick S. Martinez Gomez

Abstract:

The Flow Shop Scheduling Problem (FSSP) is a typical problem that is faced by production planning managers in Flexible Manufacturing Systems (FMS). This problem consists in finding the optimal scheduling to carry out a set of jobs, which are processed in a set of machines or shared resources. Moreover, all the jobs are processed in the same machine sequence. As in all the scheduling problems, the makespan can be obtained by drawing the Gantt chart according to the operations order, among other alternatives. On this way, an FMS presenting the FSSP can be modeled by Petri nets (PNs), which are a powerful tool that has been used to model and analyze discrete event systems. Then, the makespan can be obtained by simulating the PN through the token game animation and incidence matrix. In this work, we present an adaptive PN to obtain the makespan of FSSP by applying PN analytical tools.

Keywords: flow-shop scheduling problem, makespan, Petri nets, state equation

Procedia PDF Downloads 264
581 Collective Movement between Two Lego EV3 Mobile Robots

Authors: Luis Fernando Pinedo-Lomeli, Rosa Martha Lopez-Gutierrez, Jose Antonio Michel-Macarty, Cesar Cruz-Hernandez, Liliana Cardoza-Avendaño, Humberto Cruz-Hernandez

Abstract:

Robots are working in industry and services performing repetitive or dangerous tasks, however, when flexible movement capabilities and complex tasks are required, the use of many robots is needed. Also, productivity can be improved by reducing times to perform tasks. In the last years, a lot of effort has been invested in research and development of collective control of mobile robots. This interest is justified as there are many advantages when two or more robots are collaborating in a particular task. Some examples are: cleaning toxic waste, transportation and manipulation of objects, exploration, and surveillance, search and rescue. In this work a study of collective movements of mobile robots is presented. A solution of collisions avoidance is developed. This solution is levered on a communication implementation that allows coordinate movements in different paths were avoiding obstacles.

Keywords: synchronization, communication, robots, legos

Procedia PDF Downloads 394
580 Integral Form Solutions of the Linearized Navier-Stokes Equations without Deviatoric Stress Tensor Term in the Forward Modeling for FWI

Authors: Anyeres N. Atehortua Jimenez, J. David Lambraño, Juan Carlos Muñoz

Abstract:

Navier-Stokes equations (NSE), which describe the dynamics of a fluid, have an important application on modeling waves used for data inversion techniques as full waveform inversion (FWI). In this work a linearized version of NSE and its variables, neglecting deviatoric terms of stress tensor, is presented. In order to get a theoretical modeling of pressure p(x,t) and wave velocity profile c(x,t), a wave equation of visco-acoustic medium (VAE) is written. A change of variables p(x,t)=q(x,t)h(ρ), is made on the equation for the VAE leading to a well known Klein-Gordon equation (KGE) describing waves propagating in variable density medium (ρ) with dispersive term α^2(x). KGE is reduced to a Poisson equation and solved by proposing a specific function for α^2(x) accounting for the energy dissipation and dispersion. Finally, an integral form solution is derived for p(x,t), c(x,t) and kinematics variables like particle velocity v(x,t), displacement u(x,t) and bulk modulus function k_b(x,t). Further, it is compared this visco-acoustic formulation with another form broadly used in the geophysics; it is argued that this formalism is more general and, given its integral form, it may offer several advantages from the modern parallel computing point of view. Applications to minimize the errors in modeling for FWI applied to oils resources in geophysics are discussed.

Keywords: Navier-Stokes equations, modeling, visco-acoustic, inversion FWI

Procedia PDF Downloads 489
579 Smart Material for Bacterial Detection Based on Polydiacetylene/Polyvinyl Butyrate Fiber Composites

Authors: Pablo Vidal, Misael Martinez, Carlos Hernandez, Ananta R. Adhikari, Luis Materon, Yuanbing Mao, Karen Lozano

Abstract:

Conjugated polymers are smart materials that show tremendous practical applications in diverse subjects. Polydiacetylenes are conjugated polymers with special optical properties. In response to the environmental changes such as pH and molecular binding, it changes its color. Such an interesting chromic and emissive behavior of polydiacetylenes make them a highly popular polymer in wide areas, including biomedicine such as a biosensor. In this research, we used polyvinyl butyrate as a matrix to fibrillate polydiacetylenes. We initially prepared polyvinyl butyrate/diacetylene matrix using forcespinning technique. They were then polymerized to form polyvinyl butyrate/polydiacetylene (PVB/PDA). These matrices then studied for their bio-sensing response to gram-positive and gram-negative bacteria. The sensing ability of the PVB/PDA biosensor was observed as early as 30 min in the presence of bacteria at 37°C. Now our effort is to decrease this effective temperature to room temperature to make this device applicable in the general daily life. These chromic biosensors will find extensive application not only alert the infection but also find other promising applications such as wearable sensors and diagnostic systems.

Keywords: smart material, conjugated polymers, biosensor, polyvinyl butyrate/polydiacetylene

Procedia PDF Downloads 98
578 Out of Pocket Costs for Patients with Tuberculosis in Colombia: Evidence from Three Metropolitan Areas

Authors: Jose Hernandez, Lina Martínez, Gustavo Gonzalez, Carlos Lázaro, Diana Castrillon, Jonathan Cardona, Laura Mejía, Yina Sanchez, Luisa Ochoa, Evert Jimenez

Abstract:

Objectives: Economic analyses of tuberculosis control interventions are usually focused on the payer’s perspective. To assess the overall economic impact of the disease, out-of-pocket and indirect costs are also required. This research is aimed to estimate overall economic impact under DOTS-strategy (Directly Observed Therapy Short Course). Methods: A cross-sectional survey of 91 adult tuberculosis patients in treatment for at least two months was conducted from the society perspective. A standardized questionnaire was used in three different cities of Colombia: Medellin (poverty is 17.7%), Monteria (poverty is 36.9%) and Quibdó (poverty is 51.2%). Costs were converted to 2013 USD and categorized into two periods: diagnostics phase and treatment. Results: The median cost during diagnostics was 13$ (±SD 9.5). The median monthly patient out-of-pocket costs during treatment were 32$ (±SD 6.8), equivalent to 17% of patient’s median monthly income, estimated in 186$ (±SD 23). Costs recorded in Medellin were 47$ in Monteria was 18$ and in Quibdó was 13$. Conclusion: Patient costs under DOTS strategy are high even when services are provided free of charge. The creation or strengthening of community-based treatment supervisors could greatly impact costs of tuberculosis and lower drop-outs.

Keywords: tuberculosis, costs and cost analysis, health promotion, Colombia

Procedia PDF Downloads 334
577 Bioproduction of Phytohormones by Liquid Fermentation Using a Mexican Strain of Botryodiplodia theobromae

Authors: Laredo Alcalá Elan Iñaky, Hernandez Castillo Daniel, Martinez Hernandez José Luis, Arredondo Valdes Roberto, Gonzalez Gallegos Esmeralda, Anguiano Cabello Julia Cecilia

Abstract:

Plant hormones are a group of molecules that control different processes ranging from the growth and development of the plant until their response to biotic and abiotic stresses. In this study, the capacity of production of various phytohormones was evaluated from a strain of Botryodiplodia theobromae by liquid fermentation system using the modified Mierch medium added with a hydrolyzate compound of mead all in a reactor without agitation at 28 °C for 15 days. Quantification of the metabolites was performed using high performance liquid chromatography techniques. The results showed that a microbial broth with at least five different types of plant hormones was obtained: gibberellic acid, zeatin, kinetin, indoleacetic acid and jasmonic acid, the last one was higher than the others metabolites produced. The production of such hormones using a single type of microorganism could be in the future a great alternative to reduce production costs and similarly reduce the use of synthetic chemicals.

Keywords: biosystem, plant hormones, Botryodiplodia theobromae, fermentation

Procedia PDF Downloads 370
576 Hydrodeoxygenation of Furfural over RU Sub-Nano Particles Supported on Al₂O₃-SIO₂ Mixed Oxides

Authors: Chaima Zoulikha Tabet Zatla, Nihel Dib, Sumeya Bedrane, Juan Carlos Hernandez Garrido, Redouane Bachir, Miguel Angel Cauqui, Jose Juan Calvino Gamez

Abstract:

These last year's our planet has witnessed global warming, which is a serious threat to our lives; it has many causes, such as the CO₂ excess in the atmosphere that results from our activity, for the purpose of living in a neater and better environment, working and improving an eco-responsible energy system is a must. Valorization of biomass to produce biofuels is among the most compelling routes to decrease air pollution without considerable modification in current vehicle technology. Effective transformation of lignocellulosic biomass-derived compounds into liquid fuels and value-added chemicals is an economically viable solution. Presently, very competitive technics for the conversion of lignocellulosic biomass into platform chemicals, such as furfural and Hydroxymethylfurfural (HMF), are used. Furfural (C₅H₄O₂) is a major hemi cellulosic biomass-derived platform molecule. In our work, we focus on the valorization of lignocellulosic biomass derivative furfural that is transformed into biofuel through a hydrodeoxygenation reaction in general and involving a catalytic process. In order to get to this point, we are synthesizing and characterizing a series of catalysts with different amounts of Ru (0.5%, 1% and 2%) supported on alumina-silica mixed oxides with various molar ratios (Si/Al = 2.5; 5; 7; 10; 15). These catalysts will be characterized by numerous technics such as N₂ adsorption/desorption, Pyridine adsorption (acidity measure), FTIR, X-rays diffraction, AAS, TEM and SEM.

Keywords: furfural, ruthenium, silica-alumina, biomass, biofuel

Procedia PDF Downloads 51
575 Carbon Aerogel Spheres from Resorcinol/Phenol and Formaldehyde for CO₂ Adsorption

Authors: Jessica Carolina Hernandez Galeano, Juan Carlos Moreno Pirajan, Liliana Giraldo

Abstract:

Carbon gels are materials whose structure and porous texture can be designed and controlled on a nanoscale. Among their characteristics it is found their low density, large surface area and high degree of porosity. These materials are produced by a sol-gel polymerization of organic monomers using basic or acid catalysts, followed by drying and controlled carbonization. In this work, the synthesis and characterization of carbon aerogels from resorcinol, phenol and formaldehyde in ethanol is described. The aim of this study is obtaining different carbonaceous materials in the form of spheres using the Stöber method to perform a further evaluation of CO₂ adsorption of each material. In general, the synthesis consisted of a sol-gel polymerization process that generates a cluster (cross-linked organic monomers) from the precursors in the presence of NH₃ as a catalyst. This cluster was subjected to specific conditions of gelling and curing (30°C for 24 hours and 100°C for 24 hours, respectively) and CO₂ supercritical drying. Finally, the dry material was subjected to a process of carbonization or pyrolysis, in N₂ atmosphere at 350°C (1° C / min) for 2 h and 600°C (1°C / min) for 4 hours, to obtain porous solids that retain the structure initially desired. For this work, both the concentrations of the precursors and the proportion of ammonia in the medium where modify to describe the effect of the use of phenol and the amount of catalyst in the resulting material. Carbon aerogels were characterized by Scanning Electron Microscope (SEM), N₂ isotherms, infrared spectroscopy (IR) and X-ray Powder Diffraction (XRD) showing the obtention of carbon spheres in the nanometric scale with BET areas around 500 m2g-1.

Keywords: carbon aerogels, carbon spheres, CO₂ adsorption, Stöber method

Procedia PDF Downloads 108
574 High Frequency of Chlamydophila Pneumoniae in Children with Asthma Exacerbations

Authors: Katherine Madero Valencia, Carlos Jaramillo, Elida Dueñas, Carlos Torres, María Del Pilar Delgado

Abstract:

Asthma, described as a chronic inflammatory condition of the airways, courses accompanied by episodes known as exacerbations, characterized by a worsening of symptoms. Among the triggers, some allergen-irritative and infectious agents are found, including Chlamydophila pneumoniae which seems to play an increasingly important role. In this paper a PCR was used to detect C. pneumoniae in order to estimate the frequency of infections caused by this agent in pediatric patients with asthma exacerbations. C. pneumoniae distribution throughout the study period was also evaluated. 175 nasopharyngeal aspirates from children with asthma exacerbations were analyzed by PCR and sequencing. A global prevalence of C. pneumoniae of 53.71% was obtained. This study highlights a high circulation of C. pneumoniae during the study period, in children of all ages and especially in children under 5 years old. Molecular tests applied permit a rapid detection and improved our knowledge about these infections in children with asthma.

Keywords: Chlamydophila pneumoniae, detection, molecular techniques, pediatric asthma

Procedia PDF Downloads 516
573 Analysis of the Performance of a Solar Water Heating System with Flat Collector

Authors: Georgi Vendramin, Aurea Lúcia, Yamamoto, Carlos Itsuo, Camargo Nogueira, Carlos Eduardo, Lenz, Anderson Miguel, Souza Melegari, Samuel N.

Abstract:

The thermal performance of a solar water heating with 1.00 m2 flat plate collectors in Cascavel-PR, is which presented in this article, paper presents the solution to leverage the marketing of solar heating systems through detailed constituent materials of the solar collector studies, these abundant materials in construction, such as expanded polyethylene, PVC, aluminum and glass tubes, mixing them with new materials to minimize loss of efficiency while decreasing its cost. The system was tested during months and the collector obtained maximum recorded temperature of outlet fluid of 55 °C, while the maximum temperature of the water at the bottom of the hot water tank was 35 °C. The average daily energy collected was 19 6 MJ/d; the energy supplied by the solar plate was 16.2 MJ/d; the loss in the feed pipe was 3.2 MJ/d; the solar fraction was 32.2%, the efficiency of the collector was 45.6% and the efficiency of the system was 37.8%.

Keywords: recycling materials, energy efficiency, solar collector, solar water heating system

Procedia PDF Downloads 561
572 Online Learning Versus Face to Face Learning: A Sentiment Analysis on General Education Mathematics in the Modern World of University of San Carlos School of Arts and Sciences Students Using Natural Language Processing

Authors: Derek Brandon G. Yu, Clyde Vincent O. Pilapil, Christine F. Peña

Abstract:

College students of Cebu province have been indoors since March 2020, and a challenge encountered is the sudden shift from face to face to online learning and with the lack of empirical data on online learning on Higher Education Institutions (HEIs) in the Philippines. Sentiments on face to face and online learning will be collected from University of San Carlos (USC), School of Arts and Sciences (SAS) students regarding Mathematics in the Modern World (MMW), a General Education (GE) course. Natural Language Processing with machine learning algorithms will be used to classify the sentiments of the students. Results of the research study are the themes identified through topic modelling and the overall sentiments of the students in USC SAS

Keywords: natural language processing, online learning, sentiment analysis, topic modelling

Procedia PDF Downloads 206
571 Methylation Analysis of PHF20L1 and DACT2 Gene Promoters in Women with Breast Cancer

Authors: Marta E. Hernandez-Caballero, Veronica Borgonio-Cuadra, Antonio Miranda-Duarte, Xochitl Rojas-Toledo, Normand Garcia-Hernandez, Maura Cardenas-Garcia, Teresa Abad-Camacho

Abstract:

Breast cancer (BC) is the most common tumor in women over the world. DNA methylation is an epigenetic modification critical in CpG sites, aberrant methylation of CpG islands in promoters is a hallmark of cancer. So, gene expression can be regulated by alterations in DNA methylation. In cell lines DACT2 gene reduces the growth and migration of tumor cells by its participation in the suppression of TGFb/SMAD2/3. PHF20L1 is involved in histone acetylation therefore, it regulates transcription. Our aim was to analyze the methylation status of the DACT2 and PHF20L1 promoter regions in tumoral and healthy mammary tissue from women with BC in different progression states. The study included 77 patients from Centro Medico Nacional La Raza in Mexico City. After identifying a CpG island in DACT2 and PHF20L1 promoters, DNA methylation status was analyzed through sodium bisulfite with subsequent amplification using methylation-specific PCR. Results revealed no changes in methylation status of PHF20L1 and cancer stages (II y III) or in comparison to healthy tissues, it was demethylated. DACT2 promoter methylation was no significant between tumoral stages (II, P = 0.37; III, P = 0.17) or with healthy tissue. Previous data reported DACT2 methylated in nasopharyngeal carcinoma but in this study promoter methylation was not observed. PHF20L1 protein contains N-terminal Tudor and C-terminal plant homeodomain domains, it has been suggested that can stabilize DNMT1 regulating DNA methylation, therefore, was associated with poor prognostic in BC. We found no evidence of methylation in patients and controls in PHF20L1 promoter, so its association with BC may have no direct relation with promoter methylation. More studies including other methylation sites in these genes in BC are necessary.

Keywords: bisulfite conversion, breast cancer, DACT2, DNA methylation, PHF20L1, tumoral status

Procedia PDF Downloads 271
570 Sustainable Wood Harvesting from Juniperus procera Trees Managed under a Participatory Forest Management Scheme in Ethiopia

Authors: Mindaye Teshome, Evaldo Muñoz Braz, Carlos M. M. Eleto Torres, Patricia Mattos

Abstract:

Sustainable forest management planning requires up-to-date information on the structure, standing volume, biomass, and growth rate of trees from a given forest. This kind of information is lacking in many forests in Ethiopia. The objective of this study was to quantify the population structure, diameter growth rate, and standing volume of wood from Juniperus procera trees in the Chilimo forest. A total of 163 sample plots were set up in the forest to collect the relevant vegetation data. Growth ring measurements were conducted on stem disc samples collected from 12 J. procera trees. Diameter and height measurements were recorded from a total of 1399 individual trees with dbh ≥ 2 cm. The growth rate, maximum current and mean annual increments, minimum logging diameter, and cutting cycle were estimated, and alternative cutting cycles were established. Using these data, the harvestable volume of wood was projected by alternating four minimum logging diameters and five cutting cycles following the stand table projection method. The results show that J. procera trees have an average density of 183 stems ha⁻¹, a total basal area of 12.1 m² ha⁻¹, and a standing volume of 98.9 m³ ha⁻¹. The mean annual diameter growth ranges between 0.50 and 0.65 cm year⁻¹ with an overall mean of 0.59 cm year⁻¹. The population of J. procera tree followed a reverse J-shape diameter distribution pattern. The maximum current annual increment in volume (CAI) occurred at around 49 years when trees reached 30 cm in diameter. Trees showed the maximum mean annual increment in volume (MAI) around 91 years, with a diameter size of 50 cm. The simulation analysis revealed that 40 cm MLD and a 15-year cutting cycle are the best minimum logging diameter and cutting cycle. This combination showed the largest harvestable volume of wood potential, volume increments, and a 35% recovery of the initially harvested volume. It is concluded that the forest is well stocked and has a large amount of harvestable volume of wood from J. procera trees. This will enable the country to partly meet the national wood demand through domestic wood production. The use of the current population structure and diameter growth data from tree ring analysis enables the exact prediction of the harvestable volume of wood. The developed model supplied an idea about the productivity of the J. procera tree population and enables policymakers to develop specific management criteria for wood harvesting.

Keywords: logging, growth model, cutting cycle, minimum logging diameter

Procedia PDF Downloads 54
569 Clinical and Epidemiological Profile of Patients with Chronic Obstructive Pulmonary Disease in a Medical Institution from the City of Medellin, Colombia

Authors: Camilo Andres Agudelo-Velez, Lina María Martinez-Sanchez, Natalia Perilla-Hernandez, Maria De Los Angeles Rodriguez-Gazquez, Felipe Hernandez-Restrepo, Dayana Andrea Quintero-Moreno, Camilo Ruiz-Mejia, Isabel Cristina Ortiz-Trujillo, Monica Maria Zuluaga-Quintero

Abstract:

Chronic obstructive pulmonary disease is common condition, characterized by a persistent blockage of airflow, partially reversible and progressive, that represents 5% of total deaths around the world, and it is expected to become the third leading cause of death by 2030. Objective: To establish the clinical and epidemiological profile of patients with chronic obstructive pulmonary disease in a medical institution from the city of Medellin, Colombia. Methods: A cross-sectional study was performed, with a sample of 50 patients with a diagnosis of chronic obstructive pulmonary disease in a private institution in Medellin, during 2015. The software SPSS vr. 20 was used for the statistical analysis. For the quantitative variables, averages, standard deviations, and maximun and minimun values were calculated, while for ordinal and nominal qualitative variables, proportions were estimated. Results: The average age was 73.5±9.3 years, 52% of the patients were women, 50% of them had retired, 46% ere married and 80% lived in the city of Medellín. The mean time of diagnosis was 7.8±1.3 years and 100% of the patients were treated at the internal medicine service. The most common clinical features were: 36% were classified as class D for the disease, 34% had a FEV1 <30%, 88% had a history of smoking and 52% had oxygen therapy at home. Conclusion: It was found that class D was the most common, and the majority of the patients had a history of smoking, indicating the need to strengthen promotion and prevention strategies in this regard.

Keywords: pulmonary disease, chronic obstructive, pulmonary medicine, oxygen inhalation therapy

Procedia PDF Downloads 412
568 Clinical and Epidemiological Profile in Patients with Preeclampsia in a Private Institution in Medellin, Colombia 2015

Authors: Camilo Andrés Agudelo Vélez, Lina María Martínez Sánchez, Isabel Cristina Ortiz Trujillo, Evert Armando Jiménez Cotes, Natalia Perilla Hernández, María de los Ángeles Rodríguez Gázquez, Daniel Duque Restrepo, Felipe Hernández Restrepo, Dayana Andrea Quintero Moreno, Juan José Builes Gómez, Camilo Ruiz Mejía, Ana Lucia Arango Gómez

Abstract:

Preeclampsia is a clinical complication during pregnancy with high incidence in Colombia; therefore, it is important to evaluate the influence of external conditions and medical interventions, in order to promote measures that encourage improvements in the quality of life. Objective: Determine clinical and sociodemographic variables in women with preeclampsia. Methods: This cross-sectional study enrolled 50 patients with the diagnosis of preeclampsia, from a private institution in Medellin, during 2015. We used the software SPSS ver.20 for statistical analysis. For the qualitative variables, we calculated the mean and standard deviation, while, for ordinal and nominal levels of quantitative variables, ratios were estimated. Results: The average age was 26.8±5.9 years. The predominant characteristics were socioeconomic stratum 2 (48%), students (55%), mixed race (46%) and middle school as level of education (38%). As for clinical features, 72% of the cases were mild preeclampsia, and 22% were severe forms. The most common clinical manifestations were edema (46%), headache (62%), and proteinuria (55%). As for the Gyneco-obstetric history, 8% reported previous episodes of this disease and it was the first pregnancy for 60% of the patients. Conclusions: Preeclampsia is a frequent condition in young women; on the other hand, headache and edema were the most common reasons for consultation, therefore, doctors need to be aware of these symptoms in pregnant women.

Keywords: pre-eclampsia, hypertension, pregnancy complications, pregnancy, abdominal, edema

Procedia PDF Downloads 327
567 Development of a Tesla Music Coil from Signal Processing

Authors: Samaniego Campoverde José Enrique, Rosero Muñoz Jorge Enrique, Luzcando Narea Lorena Elizabeth

Abstract:

This paper presents a practical and theoretical model for the operation of the Tesla coil using digital signal processing. The research is based on the analysis of ten scientific papers exploring the development and operation of the Tesla coil. Starting from the Testa coil, several modifications were carried out on the Tesla coil, with the aim of amplifying the digital signal by making use of digital signal processing. To achieve this, an amplifier with a transistor and digital filters provided by MATLAB software were used, which were chosen according to the characteristics of the signals in question.

Keywords: tesla coil, digital signal process, equalizer, graphical environment

Procedia PDF Downloads 77
566 Virtual Reality and Other Real-Time Visualization Technologies for Architecture Energy Certifications

Authors: Román Rodríguez Echegoyen, Fernando Carlos López Hernández, José Manuel López Ujaque

Abstract:

Interactive management of energy certification ratings has remained on the sidelines of the evolution of virtual reality (VR) despite related advances in architecture in other areas such as BIM and real-time working programs. This research studies to what extent VR software can help the stakeholders to better understand energy efficiency parameters in order to obtain reliable ratings assigned to the parts of the building. To evaluate this hypothesis, the methodology has included the construction of a software prototype. Current energy certification systems do not follow an intuitive data entry system; neither do they provide a simple or visual verification of the technical values included in the certification by manufacturers or other users. This software, by means of real-time visualization and a graphical user interface, proposes different improvements to the current energy certification systems that ease the understanding of how the certification parameters work in a building. Furthermore, the difficulty of using current interfaces, which are not friendly or intuitive for the user, means that untrained users usually get a poor idea of the grounds for certification and how the program works. In addition, the proposed software allows users to add further information, such as financial and CO₂ savings, energy efficiency, and an explanatory analysis of results for the least efficient areas of the building through a new visual mode. The software also helps the user to evaluate whether or not an investment to improve the materials of an installation is worth the cost of the different energy certification parameters. The evaluated prototype (named VEE-IS) shows promising results when it comes to representing in a more intuitive and simple manner the energy rating of the different elements of the building. Users can also personalize all the inputs necessary to create a correct certification, such as floor materials, walls, installations, or other important parameters. Working in real-time through VR allows for efficiently comparing, analyzing, and improving the rated elements, as well as the parameters that we must enter to calculate the final certification. The prototype also allows for visualizing the building in efficiency mode, which lets us move over the building to analyze thermal bridges or other energy efficiency data. This research also finds that the visual representation of energy efficiency certifications makes it easy for the stakeholders to examine improvements progressively, which adds value to the different phases of design and sale.

Keywords: energetic certification, virtual reality, augmented reality, sustainability

Procedia PDF Downloads 157
565 Methodology for the Analysis of Energy Efficiency in Pneumatics Systems

Authors: Mario Lupaca, Karol Munoz, Victor De Negri

Abstract:

The present article presents a methodology for the improvement of the energy efficiency in pneumatic systems through the restoring of air. In this way, three techniques of expansion of a cylinder are identified: Expansion using the air of the compressor (conventional), restoring the air (efficient), and combining the air of the compressor and the restored air (hybrid). The methodology starts with the development of the GRAFCET of the system so that it can be decided whether to expand the cylinder in a conventional, efficient, or hybrid way. The methodology can be applied to any case. Finally, graphs of comparison between the three methods of expansion with certain cylinder strokes and workloads are presented, to facilitate the subsequent selection of one system or another.

Keywords: energetic, efficiency, GRAFCET, methodology, pneumatic

Procedia PDF Downloads 279
564 Artificial Neural Network Approach for Modeling and Optimization of Conidiospore Production of Trichoderma harzianum

Authors: Joselito Medina-Marin, Maria G. Serna-Diaz, Alejandro Tellez-Jurado, Juan C. Seck-Tuoh-Mora, Eva S. Hernandez-Gress, Norberto Hernandez-Romero, Iaina P. Medina-Serna

Abstract:

Trichoderma harzianum is a fungus that has been utilized as a low-cost fungicide for biological control of pests, and it is important to determine the optimal conditions to produce the highest amount of conidiospores of Trichoderma harzianum. In this work, the conidiospore production of Trichoderma harzianum is modeled and optimized by using Artificial Neural Networks (AANs). In order to gather data of this process, 30 experiments were carried out taking into account the number of hours of culture (10 distributed values from 48 to 136 hours) and the culture humidity (70, 75 and 80 percent), obtained as a response the number of conidiospores per gram of dry mass. The experimental results were used to develop an iterative algorithm to create 1,110 ANNs, with different configurations, starting from one to three hidden layers, and every hidden layer with a number of neurons from 1 to 10. Each ANN was trained with the Levenberg-Marquardt backpropagation algorithm, which is used to learn the relationship between input and output values. The ANN with the best performance was chosen in order to simulate the process and be able to maximize the conidiospores production. The obtained ANN with the highest performance has 2 inputs and 1 output, three hidden layers with 3, 10 and 10 neurons in each layer, respectively. The ANN performance shows an R2 value of 0.9900, and the Root Mean Squared Error is 1.2020. This ANN predicted that 644175467 conidiospores per gram of dry mass are the maximum amount obtained in 117 hours of culture and 77% of culture humidity. In summary, the ANN approach is suitable to represent the conidiospores production of Trichoderma harzianum because the R2 value denotes a good fitting of experimental results, and the obtained ANN model was used to find the parameters to produce the biggest amount of conidiospores per gram of dry mass.

Keywords: Trichoderma harzianum, modeling, optimization, artificial neural network

Procedia PDF Downloads 120