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El Repositorio Institucional de la Universidad de Medellín es miembro activo de la Red Colombiana de Información Científica - Minciencias
Get PDFLa Red Colombiana de Información Científica es una iniciativa que busca articular los esfuerzos que los actores del Sistema Nacional de Ciencia, Tecnología e Innovación desarrollan en el ámbito de la información, como insumo para fortalecer el desarrollo científico-tecnológico, la apropiación social del conocimiento y la articulación con redes internacionales para la gestión de la información científica. La Universidad de Medellín se vincula a esta iniciativa con los contenidos del Repositorio Institucional
Memberships Networks for High-Dimensional Fuzzy Clustering Visualization
No full textVisualizing the cluster structure of high-dimensional data is a non-trivial task that must be able to deal with the large dimensionality of the input data. Unlike hard clustering structures, visualization of fuzzy clusterings is not as straightforward because soft clustering algorithms yield more complex clustering structures. Here is introduced the concept of membership networks, an undirected weighted network constructed based on the fuzzy partition matrix that represents a fuzzy clustering. This simple network-based method allows understanding visually how elements involved in this kind of complex data clustering structures interact with each other, without relying on a visualization of the input data themselves. Experiment results demonstrated the usefulness of the proposed method for the exploration and analysis of clustering structures on the Iris flower data set and two large and unlabeled financial datasets, which describes the financial profile of customers of a local bank. © 2019, Springer Nature Switzerland AG
Foresight of the agroindustrial engineering to 2035 - Application of the delphi method as a dynamizer of curricular changes [Prospectiva de la ingeniería agroindustrial a 2035 - Aplicación del método Delphi como dinamizador de cambios curriculares]
No full textThe purpose of this article is to present the results of the application of the first Delphi round for Faculties of Agroindustrial Engineering in the framework of a prospective project, the objective was to establish research priorities, technology and areas of curricular interest for Faculties of Agroindustrial Engineering and related to the year 2035, for this purpose a survey was conducted to more than 200 national and international stakeholders related to Agroindustrial Engineering, which contained 293 variables related to the core aspects of agro-industry, that is, management, production, transformation and marketing as well as four complementary thematic groups: CIT's, sustainability, agroindustrial residues and biotechnology. On this questionnaire responses were obtained in Likert scale, which were treated through the calculation of the mode, modal frequency and percentage of consensus, among the most important results the participation of 53 experts from countries such as Spain, Peru, Mexico, Chile and Argentina, from Universities, companies and public institutions is highlighted, some of the technologies with the highest percentage of consensus were, big data, Internet of Things (digital interconnection of daily objects), sustainable agriculture, sustainable constructions, Genetically Modified Organisms, biofuels, carbon capture, use and storage (CCUS), Collaborative Learning in Virtual Worlds (Second Life), Innovation Capabilities, among others. It was observed the existence of new topics and technologies that can be taken into account for the restructuring of the curriculum of the Faculties of Agroindustrial Engineering, as well as for the prioritization of topics, technologies and innovations in terms of training experiences or training courses, extension programs, new lines of research and creation of new graduate programs. © 2019 Latin American and Caribbean Consortium of Engineering Institutions. All rights reserved
A fuzzy ELECTRE structure methodology to assess big data maturity in healthcare SMEs
No full textAdvances in technology and an increase in the amount and complexity of data that are generated in healthcare have led to an indispensable revolution in this sector related to big data. Analytics of information based on multimodal clinical data sources requires big data projects. When starting big data projects in the healthcare sector, it is often necessary to assess the maturity of an organization with respect to big data, i.e., its capacity in managing big data. The assessment of the maturity of an organization requires multicriteria decision making as there is no single criterion or dimension that defines the maturity level regarding big data but an entire set of them. Based on the ISO 15504, this article proposes a fuzzy ELECTRE structure methodology to assess the maturity level of small- and medium-sized enterprises in the healthcare sector. The obtained experimental results provide evidence that this methodology helps to determine and compare maturity levels in big data management of organizations or the evolution of maturity over time. This is also useful in terms of diagnosing the readiness of an organization before starting to implement big data initiatives or technologies. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature
Inactivation of Fusarium oxysporum Conidia in Soil with Gaseous Ozone–Preliminary Studies
No full textIn this study, the efficiency of gaseous ozone (O3) injected in the soil as an oxidizing agent for the inactivation of F. oxysporum was evaluated under laboratory conditions. The results show the treatment reached an inactivation efficiency of 76% after an applied dose of 0.40 g O3 kg ?1 soil. This shows that the injection of O3 can be a viable alternative to control pathogenic organisms in the soils. Nevertheless, it is clear that more studies on determining the effects of this treatment on soil quality are needed. © 2019, © 2019 International Ozone Association
Cerebral Cortex Atlas of Emotional States Through EEG Processing
No full textThis paper addresses the cerebral cortex maps construction from EEG signals getting an information simplification method for an emotional state phenomenon description. Bi-dimensional density distribution of main signal features are identified and a comparison to a previous approach is presented. Feature extraction scheme is performed via windowed EEG signals Stationary Wavelet Transform with the Daubechies Family (1-10); nine temporal and spectral descriptors are computed from the decomposed signal. Recursive feature selection method based on training a Random forest classifier using a one-vs-all scheme with the full features space, then a ranking procedure via gini importance, eliminating the bottom features and restarting the entire process over the new subset. Stopping criteria is the maximum accuracy. The main contribution is the analysis of the resulting subset features as a proxy for cerebral cortex maps looking for the cognitive processes understanding from surface signals. Identifying the common location of different emotional states in the central and frontal lobes, allowing to be strong parietal and temporal lobes differentiators for different emotions. © 2020, Springer Nature Switzerland AG
Evaluation of climate change adaptation in the energy generation sector in Colombia via a composite index — A monitoring tool for government policies and actions
No full textThe aim of the article is to evaluate the national adaptation to climate change in the energy generation sector in Colombia via a composite index. To build an index, a framework by stages is used, which includes the definition of the main concepts that supports the measurements; the selection of the relevant indicators using a subject matter experts; standardization of the indicators using a mathematic formula regarding the relationship between the variables that represent the adaptation to climate change; and establishment of the weights using an analytic hierarchical process of paired comparisons and the aggregation of indicators to obtain the following three sub-indexes: reactive adaptation, wherein the replacement of hydraulic energy by thermal energy is evaluated; anticipatory adaptation, which measures the gap between the generation of total energy and the demand of the national energy system; and planned adaptation, which considers indicators such as the sectoral plan for adapting to climate change, the law of alternative energies, and the generation of alternative energies as a percentage of generation capacity. By adding these sub-indices, the climate change adaptation index (CCAI) is obtained. The results of CCAI show that progress was made from a reactive adaptation scenario in which the system vulnerability was high to an anticipatory adaptation scenario wherein the vulnerability was average, indicating that the foundations for this sector to build a planned adaptation are currently being laid. © 201
Quantum decoherence effects in neutrino oscillations at DUNE
No full textIn this work, we analyze quantum decoherence in neutrino oscillations considering the open quantum system framework and oscillations through matter for three-neutrino families. Taking the Deep Underground Neutrino Experiment as a case study, we performed sensitivity analyses for two neutrino flux configurations, finding sensitivity limits for the decoherence parameters. We also offer a physical interpretation for a new peak which arises at the ?e appearance probability with decoherence. The sensitivity limits found for the decoherence parameters are ?21?1.2×10-23 GeV and ?32?7.7×10-25 GeV at 90% C.L. © 2019 authors
Impact of the time intensity of statistics in the saber 11 tests [Impacto de la intensidad horaria de la estadística en las pruebas saber 11]
No full textIntroduction. In Colombia, the General Education Law gave Educational Institutions the authority to organize their academic curricula according to their corresponding Educational Projects. Based on this institutional autonomy, some educational institutions have divided the area of mathematics into subjects such as statistics and geometry; also they have allocated a weekly time to each one of these subjects. In contrast, other institutions organize the area of mathematics by themes developed at specific times during the school year. In this sense, knowing the effects that one or another allocation could have on educational processes represents an interest for research and for teachers and educational institutions. Objective. Determine the effect that the allocation of teaching hours spent on the statistics subject could have on student performance on the Saber 11th Test in public educational institutions from Medellin-Colombia. Materials and Method. Data were extracted from the Saber 11-test results. A linear model was adjusted with mixed effects. Results. After controlling for the institution effect, it was found that some student-specific variables do impact the results in mathematics. However, allocation of teaching hours spent on statistics is not a significant factor. Conclusions. Time allocation and teaching hours spent on a statistics course do not have automatic or immediate impact on student performance. Every institution should consider strategies to promote student competencies according to their economic and social conditions. © 2019 Corporacion Universitaria Lasallista
The antimalarial chloroquine reduces the burden of persistent atrial fibrillation
No full textIn clinical practice, reducing the burden of persistent atrial fibrillation by pharmacological means is challenging. We explored if blocking the background and the acetylcholine-activated inward rectifier potassium currents (IK1 and IKACh) could be antiarrhythmic in persistent atrial fibrillation. We thus tested the hypothesis that blocking IK1 and IKACh with chloroquine decreases the burden of persistent atrial fibrillation. We used patch clamp to determine the IC50 of IK1 and IKACh block by chloroquine and molecular modeling to simulate the interaction between chloroquine and Kir2.1 and Kir3.1, the molecular correlates of IK1 and IKACh. We then tested, as a proof of concept, if oral chloroquine administration to a patient with persistent atrial fibrillation can decrease the arrhythmia burden. We also simulated the effects of chloroquine in a 3D model of human atria with persistent atrial fibrillation. In patch clamp the IC50 of IK1 block by chloroquine was similar to that of IKACh. A 14-day regimen of oral chloroquine significantly decreased the burden of persistent atrial fibrillation in a patient. Mathematical simulations of persistent atrial fibrillation in a 3D model of human atria suggested that chloroquine prolonged the action potential duration, leading to failure of reentrant excitation, and the subsequent termination of the arrhythmia. The combined block of IK1 and IKACh can be a targeted therapeutic strategy for persistent atrial fibrillation. Copyright © 2019 Tobón, Palacio, Chidipi, Slough, Tran, Tran, Reiser, Lin, Herweg, Sayad, Saiz and Noujaim. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms