Search results for: Evert Martinez Perez
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 438

Search results for: Evert Martinez Perez

348 Big Brain: A Single Database System for a Federated Data Warehouse Architecture

Authors: X. Gumara Rigol, I. Martínez de Apellaniz Anzuola, A. Garcia Serrano, A. Franzi Cros, O. Vidal Calbet, A. Al Maruf

Abstract:

Traditional federated architectures for data warehousing work well when corporations have existing regional data warehouses and there is a need to aggregate data at a global level. Schibsted Media Group has been maturing from a decentralised organisation into a more globalised one and needed to build both some of the regional data warehouses for some brands at the same time as the global one. In this paper, we present the architectural alternatives studied and why a custom federated approach was the notable recommendation to go further with the implementation. Although the data warehouses are logically federated, the implementation uses a single database system which presented many advantages like: cost reduction and improved data access to global users allowing consumers of the data to have a common data model for detailed analysis across different geographies and a flexible layer for local specific needs in the same place.

Keywords: data integration, data warehousing, federated architecture, Online Analytical Processing (OLAP)

Procedia PDF Downloads 214
347 Preparation of Carbon Monoliths from PET Waste and Their Use in Solar Interfacial Water Evaporation

Authors: Andrea Alfaro Barajas, Arturo I. Martinez

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3D photothermal structure of carbon was synthesized using PET bottles waste and sodium chloride through controlled carbonization. Characterization techniques such as X-ray photoelectron spectroscopy, X-ray diffraction, BET, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, spectrophotometry, and mechanical compression were carried out. The carbon showed physical integrity > 90%, an absorbance > 90% between 300-1000nm of the solar spectrum, and a high specific surface area from 450 to 620 m2/g. The X-ray was employed to examine the phase structure; the obtained pattern shows an amorphous material. A higher intensity of band D with respect to band G was confirmed by Raman Spectroscopy. C-OH, COOH, C-O, and C-C bonds were obtained from the deconvolution of the high-resolution C1s orbital. Macropores of 160 to 180µm and micropores of 0.5 to 2nm were observed by SEM and TEM images, respectively. Such combined characteristics of carbon confer efficient evaporation of water under 1 sun irradiation > 60%.

Keywords: solar-absorber, carbon, water-evaporation, interfacial

Procedia PDF Downloads 124
346 Pulsed Electric Field as Pretreatment for Different Drying Method in Chilean Abalone (Concholepas Concholepas) Mollusk: Effects on Product Physical Properties and Drying Methods Sustainability

Authors: Luis González-Cavieres, Mario Perez-Won, Anais Palma-Acevedo, Gipsy Tabilo-Munizaga, Erick Jara-Quijada, Roberto Lemus-Mondaca

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In this study, pulsed electric field (PEF: 2.0 kV/cm) was used as pretreatment in drying methods, vacuum microwave (VMD); freeze-drying (FD); and hot air (HAD), in Chilean abalone mollusk. Drying parameters, quality, energy consumption, and Sustainability parameters were evaluated. PEF+VMD showed better values than the other drying systems, with drying times 67% and 83% lower than PEF+FD and FD. In the quality parameters, PEF+FD showed a significantly lower value for hardness (250 N), and a lower change of color value (ΔE = 12). In the case of HAD, the PEF application did not significantly influence its processing. In energy parameters, VMD and PEF+VMD reduced energy consumption and CO2 emissions.

Keywords: PEF technology, vacuum microwave drying, energy consumption, CO2 emissions

Procedia PDF Downloads 48
345 Optimal Tracking Control of a Hydroelectric Power Plant Incorporating Neural Forecasting for Uncertain Input Disturbances

Authors: Marlene Perez Villalpando, Kelly Joel Gurubel Tun

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In this paper, we propose an optimal control strategy for a hydroelectric power plant subject to input disturbances like meteorological phenomena. The engineering characteristics of the system are described by a nonlinear model. The random availability of renewable sources is predicted by a high-order neural network trained with an extended Kalman filter, whereas the power generation is regulated by the optimal control law. The main advantage of the system is the stabilization of the amount of power generated in the plant. A control supervisor maintains stability and availability in hydropower reservoirs water levels for power generation. The proposed approach demonstrated a good performance to stabilize the reservoir level and the power generation along their desired trajectories in the presence of disturbances.

Keywords: hydropower, high order neural network, Kalman filter, optimal control

Procedia PDF Downloads 268
344 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

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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 265
343 Neuronal Networks for the Study of the Effects of Cosmic Rays on Climate Variations

Authors: Jossitt Williams Vargas Cruz, Aura Jazmín Pérez Ríos

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The variations of solar dynamics have become a relevant topic of study due to the effects of climate changes generated on the earth. One of the most disconcerting aspects is the variability that the sun has on the climate is the role played by sunspots (extra-atmospheric variable) in the modulation of the Cosmic Rays CR (extra-atmospheric variable). CRs influence the earth's climate by affecting cloud formation (atmospheric variable), and solar cycle influence is associated with the presence of solar storms, and the magnetic activity is greater, resulting in less CR entering the earth's atmosphere. The different methods of climate prediction in Colombia do not take into account the extra-atmospheric variables. Therefore, correlations between atmospheric and extra-atmospheric variables were studied in order to implement a Python code based on neural networks to make the prediction of the extra-atmospheric variable with the highest correlation.

Keywords: correlations, cosmic rays, sun, sunspots and variations.

Procedia PDF Downloads 47
342 Outstanding Lubricant Using Fluorographene as an Extreme Pressure Additive

Authors: Adriana Hernandez-Martinez, Edgar D. Ramon-Raygoza

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Currently, there has been a great interest, during the last years, on graphene due to its lubricant properties on friction and antiwear processes. Likewise, fluorographene has also been gaining renown due to its excellent chemical and physical properties which have been mostly applied in the electronics industry. Nevertheless, its tribological properties haven’t been analyzed thoroughly. In this paper, fluorographene was examined as an extreme pressure additive and the nano lubricant made with a cutting fluid and fluorographene in the range of 0.01-0.5% wt, which proved to withstand 53.78% more pounds than the conventional product and 7.12% more than the nano lubricant with graphene in a range between 0.01-0.5% wt. Said extreme pressure test was carried out with a Pin and Vee Block Tribometer following an ASTM D3233A test. The fluorographene used has a low C/F ratio, which reflects a greater presence of atomic fluorine and its low oxygen percentage, supports the substitution of oxygen-containing groups by fluorine. XPS Spectra shows high atomic fluorine content of 56.12%, and SEM analysis details the formation of long and clear crystalline structures, in the fluorographene used.

Keywords: extreme pressure additive, fluorographene, nanofluids, nanolubricant

Procedia PDF Downloads 95
341 Product Modularity, Collaboration and the Impact on Innovation Performance in Intra-Organizational R&D Networks

Authors: Daniel Martinez, Tim de Leeuw, Stefan Haefliger

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The challenges of managing a large and geographically dispersed R&D organization have been further increasing during the past years, concentrating on the leverage of a geo-graphically dispersed body of knowledge in an efficient and effective manner. In order to reduce complexity and improve performance, firms introduce product modularity as one key element for global R&D network teams to develop their products and projects in collaboration. However, empirical studies on the effects of product modularity on innovation performance are really scant. Furthermore, some researchers have suggested that product modularity promotes innovation performance, while others argue that it inhibits innovation performance. This research fills this gap by investigating the impact of product modularity on various dimensions of innovation performance, i.e. effectiveness and efficiency. By constructing the theoretical framework, this study suggests that that there is an inverted U-shaped relationship between product modularity and innovation performance. Moreover, this research work suggests that the optimum of innovation performance efficiency will be at a higher level than innovation performance effectiveness at a given product modularity level.

Keywords: modularity, innovation performance, networks, R&D, collaboration

Procedia PDF Downloads 489
340 Cellular Automata Model for Car Accidents at a Signalized Intersection

Authors: Rachid Marzoug, Noureddine Lakouari, Beatriz Castillo Téllez, Margarita Castillo Téllez, Gerardo Alberto Mejía Pérez

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This paper developed a two-lane cellular automata model to explain the relationship between car accidents at a signalized intersection and traffic-related parameters. It is found that the increase of the lane-changing probability P?ₕ? increases the risk of accidents, besides, the inflow α and the probability of accidents Pₐ? exhibit a nonlinear relationship. Furthermore, depending on the inflow, Pₐ? exhibits three different phases. The transition from phase I to phase II is of first (second) order when P?ₕ?=0 (P?ₕ?>0). However, the system exhibits a second (first) order transition from phase II to phase III when P?ₕ?=0 (P?ₕ?>0). In addition, when the inflow is not very high, the green light length of one road should be increased to improve road safety. Finally, simulation results show that the traffic at the intersection is safer adopting symmetric lane-changing rules than asymmetric ones.

Keywords: two-lane intersection, accidents, fatality risk, lane-changing, phase transition

Procedia PDF Downloads 181
339 Digitalization in Aggregate Quarries

Authors: José Eugenio Ortiz, Pierre Plaza, Josefa Herrero, Iván Cabria, José Luis Blanco, Javier Gavilanes, José Ignacio Escavy, Ignacio López-Cilla, Virginia Yagüe, César Pérez, Silvia Rodríguez, Jorge Rico, Cecilia Serrano, Jesús Bernat

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The development of Artificial Intelligence services in mining processes, specifically in aggregate quarries, is facilitating automation and improving numerous aspects of operations. Ultimately, AI is transforming the mining industry by improving efficiency, safety and sustainability. With the ability to analyze large amounts of data and make autonomous decisions, AI offers great opportunities to optimize mining operations and maximize the economic and social benefits of this vital industry. Within the framework of the European DIGIECOQUARRY project, various services were developed for the identification of material quality, production estimation, detection of anomalies and prediction of consumption and production automatically with good results.

Keywords: aggregates, artificial intelligence, automatization, mining operations

Procedia PDF Downloads 53
338 Consideration of Starlight Waves Redshift as Produced by Friction of These Waves on Its Way through Space

Authors: Angel Pérez Sánchez

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In 1929, a light redshift was discovered in distant galaxies and was interpreted as produced by galaxies moving away from each other at high speed. This interpretation led to the consideration of a new source of energy, which was called Dark Energy. Redshift is a loss of light wave frequency produced by galaxies moving away at high speed, but the loss of frequency can also be produced by the friction of light waves on their way to Earth. This friction is impossible because outer space is empty, but if it were not empty and a medium existed in this empty space, it would be possible. The consequences would be extraordinary because Universe acceleration and Dark Energy would be in doubt. This article presents evidence that empty space is actually a medium occupied by different particles, among them the most significant would-be Graviton or Higgs Boson, because let's not forget that gravity also affects empty space.

Keywords: Big Bang, dark energy, doppler effect, redshift, starlight frequency reduction, universe acceleration

Procedia PDF Downloads 37
337 Utilizing the Principal Component Analysis on Multispectral Aerial Imagery for Identification of Underlying Structures

Authors: Marcos Bosques-Perez, Walter Izquierdo, Harold Martin, Liangdon Deng, Josue Rodriguez, Thony Yan, Mercedes Cabrerizo, Armando Barreto, Naphtali Rishe, Malek Adjouadi

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Aerial imagery is a powerful tool when it comes to analyzing temporal changes in ecosystems and extracting valuable information from the observed scene. It allows us to identify and assess various elements such as objects, structures, textures, waterways, and shadows. To extract meaningful information, multispectral cameras capture data across different wavelength bands of the electromagnetic spectrum. In this study, the collected multispectral aerial images were subjected to principal component analysis (PCA) to identify independent and uncorrelated components or features that extend beyond the visible spectrum captured in standard RGB images. The results demonstrate that these principal components contain unique characteristics specific to certain wavebands, enabling effective object identification and image segmentation.

Keywords: big data, image processing, multispectral, principal component analysis

Procedia PDF Downloads 131
336 Mechanical Characterization of Mango Peel Flour and Biopolypropylene Composites Compatibilized with PP-g-IA

Authors: J. Gomez-Caturla, L. Quiles-Carrillo, J. Ivorra-Martinez, D. Garcia-Garcia, R. Balart

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The present work reports on the development of wood plastic composites based on biopolypropylene (BioPP) and mango peel flour (MPF) by extrusion and injection moulding processes. PP-g-IA and DCP have been used as a compatibilizer and as free radical initiators for reactive extrusion, respectively. Mechanical and morphological properties have been characterized in order to study the compatibility of the blends. The obtained results showed that DCP and PP-g-IA improved the stiffness of BioPP in terms of elastic modulus. Moreover, they positively increased the tensile strength and elongation at the break of the blends in comparison with the sample that only had BioPP and MPF in its composition, improving the affinity between both compounds. DCP and PP-g-IA even seem to have certain synergy, which was corroborated through FESEM analysis. Images showed that the MPF particles had greater adhesion to the polymer matrix when PP-g-IA and DCP were added. This effect was more intense when both elements were added, observing an almost inexistent gap between MPF particles and the BioPP matrix.

Keywords: biopolyproylene, compatibilization, mango peel flour, wood plastic composite

Procedia PDF Downloads 71
335 FZP Design Considering Spherical Wave Incidence

Authors: Sergio Pérez-López, Daniel Tarrazó-Serrano, José M. Fuster, Pilar Candelas, Constanza Rubio

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Fresnel Zone Plates (FZPs) are widely used in many areas, such as optics, microwaves or acoustics. On the design of FZPs, plane wave incidence is typically considered, but that is not usually the case in ultrasounds, especially in applications where a piston emitter is placed at a certain distance from the lens. In these cases, having control of the focal distance is very important, and with the usual Fresnel equation a focal displacement from the theoretical distance is observed due to the plane wave supposition. In this work, a comparison between FZP with plane wave incidence design and FZP with point source design in the case of piston emitter is presented. Influence of the main parameters of the piston in the final focalization profile has been studied. Numerical models and experimental results are shown, and they prove that when spherical wave incidence is considered for the piston case, it is possible to have a fine control of the focal distance in comparison with the classical design method.

Keywords: focusing, Fresnel zone plates, FZP, ultrasound

Procedia PDF Downloads 221
334 Women in Leadership: Mitigating Corporate Social Irresponsibility and Promoting Sustainability

Authors: Jennifer Martínez Ferrero, Emma García-Meca

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Despite substantial attention to the involvement of women directors in ESG matters, CSR, and sustainability engagement, there is limited understanding regarding the connection between corporate social irresponsibility CSI and the presence of females in leadership roles, including boards. This study contends that gender diversity is inversely correlated with corporate social irresponsibility, primarily due to attributes associated with feminine leadership styles, stakeholder focus, monitoring functions, ethical sensitivity, and risk aversion attitudes. Leveraging a dataset of non-financial European firms, our results offer insights into the effectiveness of gender diversity in preventing corporate social irresponsibility, contingent on women's visibility and legitimacy within the organization, thus supporting both tokenism and critical mass theories. Furthermore, our findings underscore the pivotal role of the institutional context, highlighting that women in board positions are only effective in curbing corporate social irresponsibility in countries where national policies are robust in combating gender inequality.

Keywords: sustainability, board, corporate governance, ESG

Procedia PDF Downloads 69
333 Efficacy and Safety by Baseline A1c with Once-Weekly Dulaglutide in the AWARD Program

Authors: Alaa Mostafa, Samuel Dagogo-Jack, Vivian Thieu, Maria Yu, Nan Zhang, Dara Schuster, Luis-Emilio Garcia-Perez

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Dulaglutide (DU), a once-weekly glucagon-like peptide-1 receptor agonist, was studied in the AWARD clinical trial program in adult patients with type 2 diabetes (T2D) and demonstrated significant hemoglobin A1c (A1c) reduction and potential for weight loss. To evaluate the efficacy and safety of DU 1.5 mg and DU 0.75 mg in patients with T2D by baseline A1c <8.5% or ≥8.5%, a post-hoc analysis was conducted on AWARD-1 to -6 and -8 at 6 months. Across 7 studies, 55% to 82% of the DU-treated patients had a baseline A1c <8.5%, and 18% to 45% had a baseline A1c ≥8.5%. The ranges of A1c reductions with baseline A1c <8.5% and ≥8.5%, respectively, were: DU 1.5 mg: -0.67% to -1.25% and -1.22% to -2.37%; DU 0.75 mg: -0.53% to -1.07% and -1.37% to -2.19%. The A1c reduction from the pooled analysis was greater in patients with baseline A1c ≥8.5% than patients with baseline A1c <8.5%, respectively: DU 1.5 mg: -1.86% and -1.02%; DU 0.75 mg: -1.75% and -0.83%. DU treatments were well tolerated among baseline A1c subgroups. Across the AWARD program, DU 1.5 mg and DU 0.75 mg demonstrated significant A1c reduction in both subgroups with an acceptable safety profile. Compared to patients with baseline A1c <8.5%, patients with baseline A1c ≥8.5% had greater A1c reduction. Disclosures: This study was supported and conducted by Eli Lilly and Company, Indianapolis, IN, USA.

Keywords: A1c reduction, dulaglutide, type 2 diabetes, weight loss

Procedia PDF Downloads 371
332 Radar Charts Analysis to Compare the Level of Innovation in Mexico with Most Innovative Countries in Triple Helix Schema Economic and Human Factor Dimension

Authors: M. Peña Aguilar Juan, Valencia Luis, Pastrana Alberto, Nava Estefany, A. Martinez, M. Vivanco, A. Castañeda

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This paper seeks to compare the innovation of Mexico from an economic and human perspective, with the seven most innovative countries according to the Global Innovation Index 2013, done by the World Intellectual Property Organization (WIPO). The above analysis suggests nine dimensions: Expenditure on R & D, intellectual property, appropriate environment to conduct business, economic stability, and triple helix for R & D, ICT Infrastructure, education, human resources and quality of life. Each dimension is represented by an indicator which is later used to construct a radial graph that compares the innovative capacity of the countries analysed. As a result, it is proposed a new indicator of innovation called The Area of Innovation. Observations are made from the results, and finally as a conclusion, those items or dimensions in which Mexico suffers lag in innovation are identify.

Keywords: dimension, measure, innovation level, economy, radar chart

Procedia PDF Downloads 440
331 Implementation of a Low-Cost Instrumentation for an Open Cycle Wind Tunnel to Evaluate Pressure Coefficient

Authors: Cristian P. Topa, Esteban A. Valencia, Victor H. Hidalgo, Marco A. Martinez

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Wind tunnel experiments for aerodynamic profiles display numerous advantages, such as: clean steady laminar flow, controlled environmental conditions, streamlines visualization, and real data acquisition. However, the experiment instrumentation usually is expensive, and hence, each test implies a incremented in design cost. The aim of this work is to select and implement a low-cost static pressure data acquisition system for a NACA 2412 airfoil in an open cycle wind tunnel. This work compares wind tunnel experiment with Computational Fluid Dynamics (CFD) simulation and parametric analysis. The experiment was evaluated at Reynolds of 1.65 e5, with increasing angles from -5° to 15°. The comparison between the approaches show good enough accuracy, between the experiment and CFD, additional parametric analysis results differ widely from the other methods, which complies with the lack of accuracy of the lateral approach due its simplicity.

Keywords: wind tunnel, low cost instrumentation, experimental testing, CFD simulation

Procedia PDF Downloads 152
330 Gender Diversity on the Board and Asymmetry Information: An Empirical Analysis for Spanish Listed Firms

Authors: David Abad, M. Encarnación Lucas-Pérez, Antonio Minguez-Vera, José Yagüe

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We examine explicitly the relation between the gender diversity on corporate boards and the levels of information asymmetry in the stock market. Based on prior evidence that suggests that the presence of women on director boards increases the quantity and quality of public disclosure by firms, we expect firms with higher gender diversity on their boards to show lower levels of information asymmetry in the market. Using a Spanish sample for the period 2004-2009, proxies for information asymmetry estimated from high-frequency data, and a system GMM methodology, we find that the gender diversity on boards is negative associated with the level of information asymmetry in the stock market. Our findings support legislative changes implemented to increase the presence of women on boards in several European countries by providing evidence that gender diverse boards have beneficial effects on stock markets.

Keywords: corporate board, female directors, gender diversity, information asymmetry, market microstructure

Procedia PDF Downloads 427
329 A Framework for Systemically Understanding and Increasing Compliance with Water Regulation in Time Limited and Uncertain Contexts

Authors: Luisa Perez-Mujica

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Traditionally, non-compliance in water regulation has been understood to be attributable to lack of information or knowledge of regulations. In other words, it is confusing behavioural change and education with communication or regulations. However, compliance is a complex response to water regulation factors including 1) knowledge and understanding of regulations; 2) perception that resources are overregulated; 3) presence of regulatory officers in the field; 4) accurate communication of what is being protected; 5) time lag between behavioral change projects and observation of outcomes and 6) how success of behavioral change is measured and evaluated. This paper presents a framework for designing education and behavioral change projects by understanding non-compliance in terms of the interaction of its factors, including a process for prioritizing projects, actions, evaluation and monitoring of outcomes. By taking a systemic approach to compliance, a more directed type of actions can be efficiently identified and prioritized, preventing the reactive nature of education and behavioral change projects.

Keywords: water regulation, compliance, behaviour change, systems thinking

Procedia PDF Downloads 211
328 Scale, Technique and Composition Effects of CO2 Emissions under Trade Liberalization of EGS: A CGE Evaluation for Argentina

Authors: M. Priscila Ramos, Omar O. Chisari, Juan Pablo Vila Martínez

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Current literature about trade liberalization of environmental goods and services (EGS) raises doubts about the extent of the triple win-win situation for trade, development and the environment. However, much of this literature does not consider the possibility that this agreement carries technological transmissions, either through trade or foreign direct investment. This paper presents a computable general equilibrium model calibrated for Argentina, where there are alternative technologies (one dirty and one clean according to carbon emissions) to produce the same goods. In this context, the trade liberalization of EGS allows to increase GDP, trade, reduce unemployment and improve the households welfare. However, the capital mobility appears as the key assumption to jointly reach the environmental target, when the positive scale effect generated by the increase in trade is offset by the change in the composition of production (composition and technical effects by the use of the clean alternative technology) and of consumption (composition effect by substitution of relatively lesspolluting imported goods).

Keywords: CGE modeling, CO2 emissions, composition effect, scale effect, technique effect, trade liberalization of EGS

Procedia PDF Downloads 344
327 Nature as a Human Health Asset: An Extensive Review

Authors: C. Sancho Salvatierra, J. M. Martinez Nieto, R. García Gonzalez-Gordon, M. I. Martinez Bellido

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Introduction: Nature could act as an asset for human health protecting against possible diseases and promoting the state of both physical and mental health. Goals: This paper aims to determine which natural elements present evidence that show positive influence on human health, on which particular aspects and how. It also aims to determine the best biomarkers to measure such influence. Method: A systematic literature review was carried out. First, a general free text search was performed in databases, such as Scopus, PubMed or PsychInfo. Secondly, a specific search was performed combining keywords in order of increasing complexity. Also the Snowballing technique was used and it was consulted in the CSIC’s (The Spanish National Research Council). Databases: Of the 130 articles obtained and reviewed, 80 referred to natural elements that influenced health. These 80 articles were classified and tabulated according to the nature elements found, the health aspects studied, the health measurement parameters used and the measurement techniques used. In this classification the results of the studies were codified according to whether they were positive, negative or neutral both for the elements of nature and for the aspects of health studied. Finally, the results of the 80 selected studies were summarized and categorized according to the elements of nature that showed the greatest positive influence on health and the biomarkers that had shown greater reliability to measure said influence. Results: Of the 80 articles studied, 24 (30.0%) were reviews and 56 (70.0%) were original research articles. Among the 24 reviews, 18 (75%) found positive results of natural elements on health, and 6 (25%) both positive and negative effects. Of the 56 original articles, 47 (83.9%) showed positive results, 3 (5.4%) both positive and negative, 4 (7.1%) negative effects, and 2 (3.6%) found no effects. The results reflect positive effects of different elements of nature on the following pathologies: diabetes, high blood pressure, stress, attention deficit hyperactivity disorder, psychotic, anxiety and affective disorders. They also show positive effects on the following areas: immune system, social interaction, recovery after illness, mood, decreased aggressiveness, concentrated attention, cognitive performance, restful sleep, vitality and sense of well-being. Among the elements of nature studied, those that show the greatest positive influence on health are forest immersion, natural views, daylight, outdoor physical activity, active transport, vegetation biodiversity, natural sounds and the green residences. As for the biomarkers used that show greater reliability to measure the effects of natural elements are the levels of cortisol (both in blood and saliva), vitamin D levels, serotonin and melatonin, blood pressure, heart rate, muscle tension and skin conductance. Conclusions: Nature is an asset for health, well-being and quality of life. Awareness programs, education and health promotion are needed based on the elements that nature brings us, which in turn generate proactive attitudes in the population towards the protection and conservation of nature. The studies related to this subject in Spain are very scarce. Aknowledgements. This study has been promoted and partially financed by the Environmental Foundation Jaime González-Gordon.

Keywords: health, green areas, nature, well-being

Procedia PDF Downloads 240
326 Designing and Evaluating Pedagogic Conversational Agents to Teach Children

Authors: Silvia Tamayo-Moreno, Diana Pérez-Marín

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In this paper, the possibility of children studying by using an interactive learning technology called Pedagogic Conversational Agent is presented. The main benefit is that the agent is able to adapt the dialogue to each student and to provide automatic feedback. Moreover, according to Math teachers, in many cases students are unable to solve the problems even knowing the procedure to solve them, because they do not understand what they have to do. The hypothesis is that if students are helped to understand what they have to solve, they will be able to do it. Taken that into account, we have started the development of Dr. Roland, an agent to help students understand Math problems following a User-Centered Design methodology. The use of this methodology is proposed, for the first time, to design pedagogic agents to teach any subject from Secondary down to Pre-Primary education. The reason behind proposing a methodology is that while working on this project, we noticed the lack of literature to design and evaluate agents. To cover this gap, we describe how User-Centered Design can be applied, and which usability techniques can be applied to evaluate the agent.

Keywords: pedagogic conversational agent, human-computer interaction, user-centered design, natural language interface

Procedia PDF Downloads 295
325 Digital Maturity Framework: A Tool to Manage the Information Technologies and Develop Activities of Innovation in Companies

Authors: Paulina Solórzano Salgado, Luis Rodrigo Valencia Pérez, Alberto de Jesús Pastrana Palma

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In this research, it is presented a digital maturity framework, which contributes to the development of small and medium-sized enterprises (SMEs) in the commercial sector. This proposal is based on three important concepts: Marketing activities in the enterprise, information and communication technologies ICT, as well as Innovation. Prior to the development of this framework, was formulated a quantitative assessment tool through a literature review, and was validated with a method used by experts, and which determines the relationship of digital marketing and innovation activities in companies. The instrument was applied to 64 Mexican companies from the Made in Mexico database, which allowed both descriptive results and correlation results. These contributed to the development of the methodology, and confirming that the management of digital marketing has a positive relation with innovation activities of companies. Also, that analytics in digital marketing is a source for its development. In this paper, the management stages and activities are presented to be developed by companies in order to generate knowledge, which will allow them to reach its digital maturity.

Keywords: digital marketing, digital maturity, innovation, SMEs

Procedia PDF Downloads 415
324 A Polyimide Based Split-Ring Neural Interface Electrode for Neural Signal Recording

Authors: Ning Xue, Srinivas Merugu, Ignacio Delgado Martinez, Tao Sun, John Tsang, Shih-Cheng Yen

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We have developed a polyimide based neural interface electrode to record nerve signals from the sciatic nerve of a rat. The neural interface electrode has a split-ring shape, with four protruding gold electrodes for recording, and two reference gold electrodes around the split-ring. The split-ring electrode can be opened up to encircle the sciatic nerve. The four electrodes can be bent to sit on top of the nerve and hold the device in position, while the split-ring frame remains flat. In comparison, while traditional cuff electrodes can only fit certain sizes of the nerve, the developed device can fit a variety of rat sciatic nerve dimensions from 0.6 mm to 1.0 mm, and adapt to the chronic changes in the nerve as the electrode tips are bendable. The electrochemical impedance spectroscopy measurement was conducted. The gold electrode impedance is on the order of 10 kΩ, showing excellent charge injection capacity to record neural signals.

Keywords: impedance, neural interface, split-ring electrode, neural signal recording

Procedia PDF Downloads 341
323 Effect of Carbon Additions on FeCrNiMnTi High Entropy Alloy

Authors: C. D. Gomez-Esparza, Z. V. Hernandez-Castro, C. A. Rodriguez-Gonzalez, R. Martinez-Sanchez, A. Duarte-Moller

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Recently, the high entropy alloys (HEA) are the focus of attention in metallurgical and materials science due to their desirable and superior properties in comparison to conventional alloys. The HEA field has promoted the exploration of several compositions including the addition of non-metallic elements like carbon, which in traditional metallurgy is mainly used in the steel industry. The aim of this work was the synthesis of equiatomic FeCrNiMnTi high entropy alloys, with minor carbon content, by mechanical alloying and sintering. The effect of the addition of carbon nanotubes and graphite were evaluated by X-ray diffraction, scanning electron microscopy, and microhardness test. The structural and microstructural characteristics of the equiatomic alloys, as well as their hardness were compared with those of an austenitic AISI 321 stainless steel processed under the same conditions. The results showed that porosity in bulk samples decreases with carbon nanotubes addition, while the equiatomic composition favors the formation of titanium carbide and increased the AISI 321 hardness more than three times.

Keywords: carbon nanotubes, graphite, high entropy alloys, mechanical alloying

Procedia PDF Downloads 162
322 Sustainable Development of Eco-Friendly Bio-Nanocomposites: Utilizing Nanocellulose Extracted From Saccharum Officinarum for Advanced Applications

Authors: Ngwenya M., Gumede T. P., Perez Camargo R. A., Motloung B.

Abstract:

This study presents the development of eco-friendly bio-nanocomposites using poly(lactic acid) (PLA), poly(caprolactone) (PCL), and their blends with nanocellulose extracted from Saccharum Officinarum. The extracted nanocellulose was optimized through chemical treatment and hydrolysis processes, yielding a sustainable and renewable resource for enhancing polymer properties. Bio-nanocomposites of PLA/nanocellulose, PCL/nanocellulose, and PLA/PCL/nanocellulose with varying nanocellulose contents (1, 3, and 5 wt%) were prepared via melt-blending and characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), dynamic mechanical analysis (DMA) and tensile testing. The results show significant improvements in the thermal and mechanical properties of the polymeric matrices upon the addition of nanocellulose, demonstrating the potential of these bio-nanocomposites for advanced applications. These developments are promising for obtaining bio-nanocomposites from local bio-sources, leading to more sustainable and eco-friendly alternatives to traditional materials.

Keywords: bionanocomposites, polycaprolactone, poly(lactic acid), nanocellulose, saccharum officinarum

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321 Appearance and Magnitude of Dynamic Pressure in Micro-Scale of Subsonic Airflow around Symmetric Objects

Authors: Shehret Tilvaldyev, Jorge Flores-Garay, Alfredo Villanueva, Erwin Martinez, Lazaro Rico

Abstract:

The efficiency of modern transportation is severely compromised by the prevalence of turbulent drag. The high level of turbulent skin-friction occurring, e.g., on the surface of an aircraft, automobiles or the carriage of a high-speed train, is responsible for excess fuel consumption and increased carbon emissions. The environmental, political, and economic pressure to improve fuel efficiency and reduce carbon emissions associated with transportation means that reducing turbulent skin-friction drag is a pressing engineering problem. The dynamic pressure of subsonic airflow around solid objects creates lift, but also induces drag force. This paper is presenting the results of laboratory experiments, investigating appearance and magnitude of dynamic pressure in micro scale of subsonic air flow around right cylinder and symmetrical airfoil.

Keywords: airflow, dynamic pressure, micro scale, symmetric object

Procedia PDF Downloads 353
320 Tenofovir-Amino Acid Conjugates Act as Polymerase Substrates: Implications for Avoiding Cellular Phosphorylation in the Discovery of Nucleotide Analogs

Authors: Weijie Gu, Sergio Martinez, Hoai Nguyen, Hongtao Xu, Piet Herdewijn, Steven De Jonghe, Kalyan Das

Abstract:

Nucleotide analogs are used for treating viral infections such as HIV, hepatitis B, hepatitis C, influenza, and SARS-CoV-2. To become polymerase substrates, a nucleotide analog must be phosphorylated by cellular kinases, which are rate-limiting. The goal of this study is to develop dNTP/NTP analogs directly from nucleotides. Tenofovir (TFV) analogs were synthesized by conjugating with natural or unnatural amino acids. It demonstrates that some conjugates act as dNTP analogs, and HIV-1 reverse transcriptase (RT) catalytically incorporates the TFV part as the chain terminator. X-ray structures in complex with HIV-1 RT/dsDNA showed binding of the conjugates at the polymerase active site, however, in different modes in the presence of Mg²⁺ vs. Mn²⁺ ions. The adaptability of the compounds is seemingly essential for catalytic incorporation of TFV by RT. 4d with a carboxyl sidechain demonstrated the highest incorporation. 4e showed weak incorporation and rather behaved as a dNTP-competitive inhibitor. This result advocates the feasibility of designing NTP/dNTP analogs by chemical substitutions to nucleotide analogs.

Keywords: dNTP analogs, nucleotide analogs, polymerase, tenofovir, X-ray structure

Procedia PDF Downloads 120
319 Behavior of Current in a Semiconductor Nanostructure under Influence of Embedded Quantum Dots

Authors: H. Paredes Gutiérrez, S. T. Pérez-Merchancano

Abstract:

Motivated by recent experimental and theoretical developments, we investigate the influence of embedded quantum dot (EQD) of different geometries (lens, ring and pyramidal) in a double barrier heterostructure (DBH). We work with a general theory of quantum transport that accounts the tight-binding model for the spin dependent resonant tunneling in a semiconductor nanostructure, and Rashba spin orbital to study the spin orbit coupling. In this context, we use the second quantization theory for Rashba effect and the standard Green functions method. We calculate the current density as a function of the voltage without and in the presence of quantum dots. In the second case, we considered the size and shape of the quantum dot, and in the two cases, we worked considering the spin polarization affected by external electric fields. We found that the EQD generates significant changes in current when we consider different morphologies of EQD, as those described above. The first thing shown is that the current decreases significantly, such as the geometry of EQD is changed, prevailing the geometrical confinement. Likewise, we see that the current density decreases when the voltage is increased, showing that the quantum system studied here is more efficient when the morphology of the quantum dot changes.

Keywords: quantum semiconductors, nanostructures, quantum dots, spin polarization

Procedia PDF Downloads 231