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Ítem Adaptive LAMDA applied to identify and regulate a process with variable dead time(Institute of Electrical and Electronics Engineers Inc., 2020-01-01) Morales L.; Pozo D.; Aguilar J.; Rosales A.; Universidad EAFIT. Departamento de Ingeniería de Sistemas; I+D+I en Tecnologías de la Información y las ComunicacionesIn this paper, an adaptive intelligent controller based on the fuzzy algorithm called LAMDA (Learning Algorithm for Multivariable Data Analysis) is presented in order to identify and regulate a process with variable dead time. The original algorithm has been used for supervised and unsupervised learning, whose main field of application is the identification of functional states of the systems. In this work a modification of LAMDA has been implemented which is capable of online learning using hybrid techniques. The proposal consists of two stages: training stage to learn about the unknown plant in order to establish initial parameters to the controller, and a second phase, called application, in which the control strategy is updated using online learning. The proposed method is tested in the control objective of regulation of a process with variable dead time, to analyze the viability of its utilization in these types of systems in which their dynamics are variable and unknown. © 2020 IEEE.Ítem A collaborative tool for synchronous distance education(2004-01-01) Agudelo, A.; Escobar, L.; Restrepo, J.; Quiroz, A.; Trefftz, H.; Universidad EAFIT. Departamento de Ingeniería de Sistemas; I+D+I en Tecnologías de la Información y las ComunicacionesIn this paper we report results of the use of a telepresence application in a simulated distance education setting. The application combines video-conference with a networked virtual environment in which the instructor and the students can experiment with virtual object in a collaborative manner. The teaching for Understanding (TFU) framework is used as the pedagogical approach. Current preliminary results show that the combination of the telepresence application with TFU, can compensate for the lack of physical presence of the instructor in the classroom.Ítem Collaborative virtual environments for teaching physics(SPRINGER, 2007-01-01) Giraldo, F.; Rojas, Á.M.J.; Esteban, P.; Trefftz, H.; Universidad EAFIT. Departamento de Ingeniería de Sistemas; I+D+I en Tecnologías de la Información y las ComunicacionesEafit University created a Telepresence application for distance education. It supports bidirectional audio and video and a shared virtual environment that allows the instructor and students to manipulate virtual objects in a collaborative manner, thereby reinforcing the learning process. In this paper we report the experience of creating new contents and deploying the tool in a Physics course at Universidad del Quindío. The tool was improved an extended in order to include new functionality and make it easier for development teams to create new content. Teaching for Understanding was used as pedagogical framework for course creation and also as a guide to develop the interviews that were used to capture user's perceptions and to asses the improvements in the learning process. The results showed that the use of the tool had a positive impact on the students' understanding of the topics at hand. © 2007 Springer.Ítem Design and usability evaluation of a multi-input interface in an idTV environment(Springer Verlag, 2017-01-01) Téllez J.F.; Montoya J.C.; Trefftz H.; Universidad EAFIT. Departamento de Ingeniería de Sistemas; I+D+I en Tecnologías de la Información y las ComunicacionesIn recent years, and considering the rise of Interactive Digital Television (idTV), it has been great interest in the design of applications and services for this platform. However, the success of these applications largely depends on the ease of use and how users interact with them. For this reason, we have explored different interfaces and modes of interaction to improve the user experience with these applications in comparison with the traditional Remote-Control (RC). This article presents an interaction with idTV applications using multiple input control interfaces with different modes of interaction such as touch buttons, gesture recognition, voice recognition, and recognition of movements. These modes of interaction were validated through usability testing using a model of quasi-experimental evaluation of three dimensions, where each dimension represents respectively: users, tasks and control interfaces. As a result of the qualitative and quantitative assessments, we performed an analysis of possible improvements in the usability of a particular application of idTV. The results showed few differences between one multi-input control interface and one RC in tasks the user was familiar with, on the opposite, significant differences were found in performing tasks involving greater user interaction, such as the text input or navigation between menus. © Springer International Publishing AG 2017.Ítem Enhanced molecular visualization of root colonization and growth promotion by Bacillus subtilis EA-CB0575 in different growth systems(Elsevier GmbH, 2018-01-01) Posada, L.F.; Álvarez, J.C.; Romero-Tabarez, M.; de-Bashan, L.; Villegas-Escobar, V.; Universidad EAFIT. Departamento de Ciencias; Biodiversidad, Evolución y ConservaciónBacillus subtilis EA-CB0575 is a plant growth-promoting bacterium (PGPB) associated with banana and tomato crops. Root colonization is an important trait for PGPB microorganisms and potentiates the bacterial effect related to the mechanisms of plant growth promotion. Therefore, detection of bacterial colonization of roots in different culture systems is important in the study of plant–microorganism interactions. In this study, fluorescent in situ hybridization (FISH) and catalyzed reporter deposition–FISH (CARD–FISH) were evaluated to determine the colonization ability of B. subtilis EA-CB0575 on banana and tomato roots planted on solid and liquid Murashige and Skoog medium (MS(S) and MS(L), respectively) and in soil for tomato plants. Results showed B. subtilis colonization 0–30 days post inoculation for banana and tomato plants in different culture systems with differential distribution of bacterial cells along tomato and banana roots. FISH and CARD–FISH methodologies were both successful in detecting B. subtilis colonies, but CARD–FISH proved to be superior due to its enhanced fluorescence signal. The presence of bacteria correlated with the promotion of plant growth in both plant species, providing clues to relate rhizospheric colonization with improvement in plant growth. FISH and CARD–FISH analysis results suggested the presence of native microbiota on the roots of in vitro banana plants, but not on those of tomato plants. © 2018 Elsevier GmbHÍtem An innovation model in curriculum design for teaching engineering at universidad EAFIT(Institute of Electrical and Electronics Engineers Inc., 2015-01-01) Zea, C.M.; Rodriguez, A.; Bueno, N.A.; Universidad EAFIT. Departamento de Ingeniería de Sistemas; I+D+I en Tecnologías de la Información y las ComunicacionesConstant changes in technology pose continuous challenges for higher education institutions that are training the engineers of the future. These changes are making it necessary to adapt the curriculum in order to develop the skills needed by the XXI century engineer. Moreover, instead of thinking in a large curriculum reform at a specific moment, it is necessary to define curriculum management processes that include change as a natural component of the process. In addition to these global trends, each institution has a particular context and thus, the analysis in each institution has unique characteristics, a common methodological approach, and a reference model that can be built as long as it is flexible enough to include that context. This paper describes a model developed for curriculum management inside the School of Engineering at Universidad EAFIT - Colombia. This model includes the institutional context and is based on a process approach defined by the Business Process Management (BPM) methodology. The model uses the Burlton Hexagon as a theoretical framework to identify organizational structure, strategies, policies, infrastructure, technology tools and human capital. It is also a mechanism for specifying curricular macro processes including the global and institutional context. The proposed model is based on three pillars: (a) scientific research in education, which promotes the use of the scientific method as a strategy to ensure an approach to problems based on evidence which allows the construction of educational innovation projects, (b) education engineering focused on engineering education, which transforms the learning by developing basic, professional, and transversal skills as well as those specific for an engineer of the XXI century, and (c) interactive educational communities, both face to face and virtual, as spaces for knowledge management that support collaborative working and experience-sharing, managed by its members working together promoting initiatives to develop educational innovation projects focused on specific topics, that answer questions related to teaching and learning needs. The formulation and development of educational innovation projects are the responses to different needs identified on specific courses that are transformed into research questions. These projects aim to renew the curriculum so that it dynamically evolves based on classroom experiences. Thus, the curriculum renewal is based on critical thinking about the problems found in engineering education. The use of the scientific method and the collaborative approach enables drawing solid conclusions based on the experimental results. The model proposes the formulation and development of innovative educational projects in which scientific research applied in education aims to transform teaching, academic and administrative practices. As consequence, curricular innovations that integrate learning objects and educational, methodological and assessment strategies, are developed by an interactive learning community composed by teachers. Finally, the results obtained by applying the model in some courses in the School of Engineering of Universidad EAFIT are presented. These results include reducing the drop-out rate of students, redefining admission and graduation profiles, and micro-curricular redesign based on competences using projects, among others. © 2014 IEEE.Ítem Planktic foraminiferal diversity: Logistic growth overprinted by a varying environment(Universidad Nacional de Colombia, 2016-09-01) Cárdenas-Rozo, A.L.; Harries, P.J.; Universidad EAFIT. Departamento de Ciencias; Biodiversidad, Evolución y ConservaciónThis study statistically assesses the relationship between the planktic foraminiferal long-term diversity pattern (~170 Ma to Recent) and four major paleobiological diversification models: (i) the ‘Red Queen’ (Van Valen, 1973; Raup et al., 1973), (ii) the turnover-pulse (Vrba, 1985; Brett and Baird, 1995), (iii) the diversity-equilibrium (Sepkoski, 1978; Rosenzweig, 1995), and (iv) the ‘complicated logistic growth’ (Alroy, 2010a). Our results suggest that the long-term standing diversity pattern and the interplay between origination and extinction rates displayed by this group do not correspond to the first three models, but can be more readily explained by the fourth scenario. Consequently, these patterns are likely controlled by a combination of planktic foraminiferal interspecific competition as well as various environmental changes such as marine global temperatures that could impacted the niches within the upper mixed layer within the oceans. Moreover, as other global long-term patterns have been interpreted as reflecting ‘complicated logistic growth’, this study further suggests that the interplay between abiotic and biotic factors are fundamental elements influencing the evolutionary processes over the extensive history of the biota. © 2016 Author(s).