Examinando por Materia "Problem solving"
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Ítem 2D shape similarity as a complement for Voronoi-Delone methods in shape reconstruction(PERGAMON-ELSEVIER SCIENCE LTD, 2005-02-01) Ruiz, O.E.; Cadavid, C.A.; Granados, M.; Peña, S.; Vásquez, E.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Laboratorio CAD/CAM/CAEIn surface reconstruction from planar cross sections it is necessary to build surfaces between 2D contours in consecutive cross sections. This problem has been traditionally attacked by (i) direct reconstruction based on local geometric proximity between the contours, and (ii) classification of topological events between the cross sections. These approaches have been separately applied with limited success. In case (i), the resulting surfaces may have overstretched or unnatural branches. These arise from local contour proximity which does not reflect global similarity between the contours. In case (ii), the topological events are identified but are not translated into the actual construction of a surface. This article presents an integration of the approaches (i) and (ii). Similarity between the composite 2D regions bounded by the contours in consecutive cross sections is used to: (a) decide whether a surface should actually relate two composite 2D regions, (b) identify the type and location of topological transitions between cross sections and (c) drive the surface construction for the regions found to be related in step (a). The implemented method avoids overstretched or unnatural branches, rendering a surface which is both geometrically intuitive and topologically faithful to the cross sections of the original object. The presented method is a good alternative in cases in which correct reproduction of the topology of the surface (e.g. simulation of flow in conduits) is more important than its geometry (e.g. assessment of tumor mass in radiation planning). © 2004 Elsevier Ltd. All rights reserved.Ítem Development of a model for evaluating the NPD process in SMEs: A Latin American experience(Elsevier, 2014-01-01) Hernandez, M.C.; Montoya, M.V.; Martínez, J.F.This article presents the findings resulting from a research project carried out in Medellin, Colombia, that was aimed at developing a model of diagnosis for the NPD process in manufacturing SMEs, adapted to the Latin American context. Four aspects were considered to develop the model: (i) Rational logic for problem solving based on the paradigm that a problem can be solved through systematic application of general principles and standardized knowledge, (ii) The Grounded Theory research approach, (iii) Integration of learning processes based on reflective and, (iv) Kolb's learning cycle as basic premises for the generation of a prescriptive model considering that the diagnosis process involves a learning process. Results obtained from the four companies selected for the study helped to validate an initial version. The model has proven to have great potential to improve the NPD process, as well as an opportunity to develop future comparative studies. Findings in the discussion and further reflection generated by the application of the four tools that encompasses the model within the companies, proved to be appropriated as a reflective practice and also a continuing learning process for SMEs. © 2014 Published by Elsevier B.V.Ítem Development of a model for evaluating the NPD process in SMEs: A Latin American experience(Elsevier, 2014-01-01) Hernandez, M.C.; Montoya, M.V.; Martínez, J.F.; Universidad EAFIT. Departamento de Administración; Estudios en Mantenimiento (GEMI)This article presents the findings resulting from a research project carried out in Medellin, Colombia, that was aimed at developing a model of diagnosis for the NPD process in manufacturing SMEs, adapted to the Latin American context. Four aspects were considered to develop the model: (i) Rational logic for problem solving based on the paradigm that a problem can be solved through systematic application of general principles and standardized knowledge, (ii) The Grounded Theory research approach, (iii) Integration of learning processes based on reflective and, (iv) Kolb's learning cycle as basic premises for the generation of a prescriptive model considering that the diagnosis process involves a learning process. Results obtained from the four companies selected for the study helped to validate an initial version. The model has proven to have great potential to improve the NPD process, as well as an opportunity to develop future comparative studies. Findings in the discussion and further reflection generated by the application of the four tools that encompasses the model within the companies, proved to be appropriated as a reflective practice and also a continuing learning process for SMEs. © 2014 Published by Elsevier B.V.Ítem Estudio, análisis y propuestas de soluciones a la movilidad vial en algunas zonas del Valle de Aburrá(Universidad EAFIT, 2011) Meneses Solá, Luis Carlos; Jaramillo López, Ricardo; Agudelo Ospina, Jhon JairoÍtem Experiences in implementing design heuristics for innovation in product design(Springer-Verlag France, 2018-08-01) Restrepo J.; Ríos-Zapata D.; Mejía-Gutiérrez R.; Nadeau J.-P.; Pailhès J.; Universidad EAFIT. Departamento de Ingeniería de Diseño; Ingeniería de Diseño (GRID)The aided decision processes are expected to improve the design tasks by the reduction of uncertainty, which is one of the principal aspects that interferes with designer choices. These methods can optimise the problem solution by the time reduction in the iterative decision-cycles that can be based on previous knowledge. This article is based in the utilisation of a knowledge based method in design heuristics, which are defined as a set of procedures that allows both, discovery and acquisition, of a solution for a particular problem by the implementation of a strategy, guided by knowledge derived from the experience. This is applied to design area by the extrapolation of technical or conceptual knowledge that has been previously applied and proven in similar problem-solving processes and providing reference points within designs processes as well. For this reason the research focuses on the development of a design case in order to evaluate the interaction between the user and the guided problem approach. The objective was the analysis between two different design processes by the comparison of the implementation of heuristics based method and conventional design techniques in a design case. The purpose was to compare the outcomes of both experiments, taking as a basis the following setup: The design case proposed was carried out by two different teams, where the first team was instructed to use conventional problem-solving approaches such as Pahl & Beitz and Ulrich & Eppinger and the second one was intended to use the heuristics based method. The design task given to both teams was the development of a methane production system by the use of organic waste with the incorporation of technologies to allow the variables control, in other words, an automated biodigester; this allows to have an outcome all teams easy to comparable between each other. Each team performed the task separately, in order to avoid external influence in the process. All of this to proof that with the aid of tools based on heuristic strategies might enhance the innovation and diversification in design alternatives and strengthens conceptual exploration by providing more detailed concepts in early stages of the process. © 2017, Springer-Verlag France SAS.Ítem Funciones(Universidad EAFIT, 2015) Esteban Duarte, Pedro Vicente; Esteban Duarte, Pedro Vicente. Universidad EAFIT, Escuela de Ciencias, Ciencias Básicas, Medellín, Colombia; Proyecto 50El concepto de función es tal vez el más importan en el Cálculo -- A partir de él, se definen el límite, la continuidad, la derivada, la integral de funciones, etc. -- Además, las funciones describen modelos en muchas ramas de la ciencia, como la Física, la Economía, la Biología, entre otras -- El estudio de las funciones, sus propiedades, gráficas e interpretaciones, acordes con el contexto, permiten describir un sin número de aplicaciones y solucionar una gran variedad de problemas de diversos tiposÍtem Intervención comportamental para fortalecer la resolución de problemas en los jugadores del club deportivo Megatalentos de la categoría “Primera B, semiprofesional sub-21” de la Liga Antioqueña de fútbol(Universidad EAFIT, 2024) Infante Sarmiento, Javier; Piedrahita Gil, Juan David; Acevedo Mesa, Carmen NataliaThe main purpose study, is to run a behavioral intervention to strengthen problem solving in Megatalentos club members under 21 division Antioquia soccer league. Currently the team shows high levels of dropout members. Metodology applied was the Wheel of change (Michie et al., 2014, p. 40). The intervention was developed in 3 phases: diagnosis, intervention and results evaluation, showing players increasing training attendance, better comunication with team´s coaching staff when troubles came up, creating solutions and better team conversations presenting alternatives to improve performance, and showing good achievements in problem solving without losing process and having greater participation in the team. Some recomendations were develop to continue the research working on other behavioral intervention methods allowing análysis with longer term results.Ítem Métodos computacionales para la solución de problemas de optimización bajo incertidumbre y problemas inversos, desde la perspectiva intervalo-valuada(Universidad EAFIT, 2011) Cano Cadavid, Andrés Felipe; Puerta Yepes, María EugeniaÍtem Multi-modal interface for a real-time CFD solver(2007-01-01) Kasakevich, M.; Boulanger, P.; Bischof, W.F.; Garcia, M.; Kasakevich, M.; Boulanger, P.; Bischof, W.F.; Garcia, M.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Mecánica AplicadaAdvances in computer processing power and networking over the past few years have brought significant changes to the modeling and simulation of complex phenomena. Problems that formerly could only be tackled in batch mode, with their results visualized afterwards, can now be monitored whilst in progress using graphical means. In certain cases, it is even possible to alter parameters of the computation whilst it is running, depending on what the scientist perceives in the current visual output. This ability to monitor and change parameters of the computational process at any time and from anywhere is called computational steering. Combining this capability with advanced multi-modal tools to explore the data produced by these systems are key to our approach. In this paper, we present an advanced multi-modal interface where sonification and 3D visualization are used in a computational steering environment specialized to solve real-time Computational Fluid Dynamics (CFD) problems. More specifically, this paper describes how sonification of CFD data can be used to augment 3D visualization. © 2006 IEEE.Ítem NMPC controller applied to the operation of an internal combustion engine: formulation and solution of the optimization problem in real time(Springer-Verlag France, 2018-02-01) Chica, J.A.V.; Torres, A.G.D.; Acosta Maya, Diego Andres; Chica, J.A.V.; Torres, A.G.D.; Acosta Maya, Diego Andres; Universidad EAFIT. Departamento de Ingeniería de Producción; Ingeniería, Energía, Exergía y Sostenibilidad (IEXS)Numerical optimization solve problems efficiently where such efficiency is focused on the speed with which the optimal x* is achieved, is open line of research and strong work in the scientific community in order to achieve control systems in dynamic processes with response times of the order of milliseconds. A clear example of this, is the implementation of optimal controller’s combustion engines. For subsequent approach to the design and implementation of nonlinear model predictive control controllers, it has made a comparison of yields algorithms quadratic programming by active set with linearization restrictions, and sequential quadratic programming with single shooting technique to solve quadratic optimization problem formulation referred to a dynamic internal combustion engine of spark ignition, in embedded systems with real-time processing. © 2016, Springer-Verlag France.Ítem NMPC controller applied to the operation of an internal combustion engine: formulation and solution of the optimization problem in real time(Springer-Verlag France, 2018-02-01) Chica, J.A.V.; Torres, A.G.D.; Acosta Maya, Diego Andres; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de ProcesosNumerical optimization solve problems efficiently where such efficiency is focused on the speed with which the optimal x* is achieved, is open line of research and strong work in the scientific community in order to achieve control systems in dynamic processes with response times of the order of milliseconds. A clear example of this, is the implementation of optimal controller’s combustion engines. For subsequent approach to the design and implementation of nonlinear model predictive control controllers, it has made a comparison of yields algorithms quadratic programming by active set with linearization restrictions, and sequential quadratic programming with single shooting technique to solve quadratic optimization problem formulation referred to a dynamic internal combustion engine of spark ignition, in embedded systems with real-time processing. © 2016, Springer-Verlag France.Ítem NMPC controller applied to the operation of an internal combustion engine: formulation and solution of the optimization problem in real time(Springer-Verlag France, 2018-02-01) Chica, J.A.V.; Torres, A.G.D.; Acosta Maya, Diego Andres; Chica, J.A.V.; Torres, A.G.D.; Acosta Maya, Diego Andres; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)Numerical optimization solve problems efficiently where such efficiency is focused on the speed with which the optimal x* is achieved, is open line of research and strong work in the scientific community in order to achieve control systems in dynamic processes with response times of the order of milliseconds. A clear example of this, is the implementation of optimal controller’s combustion engines. For subsequent approach to the design and implementation of nonlinear model predictive control controllers, it has made a comparison of yields algorithms quadratic programming by active set with linearization restrictions, and sequential quadratic programming with single shooting technique to solve quadratic optimization problem formulation referred to a dynamic internal combustion engine of spark ignition, in embedded systems with real-time processing. © 2016, Springer-Verlag France.Ítem Sensitivity analysis in optimized parametric curve fitting(EMERALD GROUP PUBLISHING LIMITED, 2015-03-02) Ruiz, Oscar E.; Cortes, Camilo; Acosta, Diego A.; Aristizabal, Mauricio; Universidad EAFIT. Departamento de Ingeniería Mecánica; Laboratorio CAD/CAM/CAEPurpose-Curve fitting from unordered noisy point samples is needed for surface reconstruction in many applications. In the literature, several approaches have been proposed to solve this problem. However, previous works lack formal characterization of the curve fitting problem and assessment on the effect of several parameters (i.e. scalars that remain constant in the optimization problem), such as control points number (m), curve degree (b), knot vector composition (U), norm degree (k ), and point sample size (r) on the optimized curve reconstruction measured by a penalty function ( f ). The paper aims to discuss these issues. Design/methodology/approach-A numerical sensitivity analysis of the effect of m, b, k and r on f and a characterization of the fitting procedure from the mathematical viewpoint are performed. Also, the spectral (frequency) analysis of the derivative of the angle of the fitted curve with respect to u as a means to detect spurious curls and peaks is explored. Findings-It is more effective to find optimum values for m than k or b in order to obtain good results because the topological faithfulness of the resulting curve strongly depends on m. Furthermore, when an exaggerate number of control points is used the resulting curve presents spurious curls and peaks. The authors were able to detect the presence of such spurious features with spectral analysis. Also, the authors found that the method for curve fitting is robust to significant decimation of the point sample. Research limitations/implications-The authors have addressed important voids of previous works in this field. The authors determined, among the curve fitting parameters m, b and k, which of them influenced the most the results and how. Also, the authors performed a characterization of the curve fitting problem from the optimization perspective. And finally, the authors devised a method to detect spurious features in the fitting curve. Practical implications-This paper provides a methodology to select the important tuning parameters in a formal manner. Originality/value-Up to the best of the knowledge, no previous work has been conducted in the formal mathematical evaluation of the sensitivity of the goodness of the curve fit with respect to different possible tuning parameters (curve degree, number of control points, norm degree, etc.). © Emerald Group Publishing Limited.Ítem Sensitivity analysis in optimized parametric curve fitting(EMERALD GROUP PUBLISHING LIMITED, 2015-03-02) Ruiz, Oscar E.; Cortes, Camilo; Acosta, Diego A.; Aristizabal, Mauricio; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de ProcesosPurpose-Curve fitting from unordered noisy point samples is needed for surface reconstruction in many applications. In the literature, several approaches have been proposed to solve this problem. However, previous works lack formal characterization of the curve fitting problem and assessment on the effect of several parameters (i.e. scalars that remain constant in the optimization problem), such as control points number (m), curve degree (b), knot vector composition (U), norm degree (k ), and point sample size (r) on the optimized curve reconstruction measured by a penalty function ( f ). The paper aims to discuss these issues. Design/methodology/approach-A numerical sensitivity analysis of the effect of m, b, k and r on f and a characterization of the fitting procedure from the mathematical viewpoint are performed. Also, the spectral (frequency) analysis of the derivative of the angle of the fitted curve with respect to u as a means to detect spurious curls and peaks is explored. Findings-It is more effective to find optimum values for m than k or b in order to obtain good results because the topological faithfulness of the resulting curve strongly depends on m. Furthermore, when an exaggerate number of control points is used the resulting curve presents spurious curls and peaks. The authors were able to detect the presence of such spurious features with spectral analysis. Also, the authors found that the method for curve fitting is robust to significant decimation of the point sample. Research limitations/implications-The authors have addressed important voids of previous works in this field. The authors determined, among the curve fitting parameters m, b and k, which of them influenced the most the results and how. Also, the authors performed a characterization of the curve fitting problem from the optimization perspective. And finally, the authors devised a method to detect spurious features in the fitting curve. Practical implications-This paper provides a methodology to select the important tuning parameters in a formal manner. Originality/value-Up to the best of the knowledge, no previous work has been conducted in the formal mathematical evaluation of the sensitivity of the goodness of the curve fit with respect to different possible tuning parameters (curve degree, number of control points, norm degree, etc.). © Emerald Group Publishing Limited.Ítem Shape optimisation of continuum structures via evolution strategies and fixed grid finite element analysis(SPRINGER, 2004-01-01) Garcia, MJ; Gonzalez, CA; Mecánica AplicadaEvolution strategies (ES) are very robust and general techniques for finding global optima in optimisation problems. As with all evolutionary algorithms, ES apply evolutionary operators and select the most fit from a set of possible solutions. Unlike genetic algorithms, ES do not use binary coding of individuals, working instead with real variables. Many recent studies have applied evolutionary algorithms to structural problems, particularly the optimisation of trusses. This paper focuses on shape optimisation of continuum structures via ES. Stress analysis is accomplished by using the fixed grid finite element method, which reduces the computing time while keeping track of the boundary representation of the structure. This boundary is represented by b-spline functions, circles, and polylines, whose control points constitute the parameters that govern the shape of the structure. Evolutionary operations are applied to each set of variables until a global optimum is reached. Several numerical examples are presented to illustrate the performance of the method. Finally, structures with multiple load cases are considered along with examples illustrating the results obtained.Ítem Smart experience engineering to support collaborative design problems based on constraints modelling(IOS PRESS, 2014-01-01) Cálad-Álvarez, A.; Mejía-Gutiérrez, R.; Sanín, C.M.; Szczerbicki, E.Engineering design is a knowledge intensive process. Experts' experiences from different product life-cycle stages play a key role in problem solving during design decision making by linking up knowledge to find better solutions for a specific design problem. Different approaches have been used to support Collaborative and Concurrent Product Design, such as Constraint Satisfaction Problem (CSP) modelling. Additionally, due to the need of capitalizing these experiences, the Set of Experience Knowledge Structure (SOEKS) is used to store and manage experiences of decision making process. However it was necessary to adapt the structure to property manage the constraints approach used in Engineering Design. This article presents a proposed adaptation to SOEKS structure in order to be able to store and reuse CSP design experiences for further re-use and analysis of multiple experiences. Finally, a case study is presented in order to show how the proposed approach can be used in the industrial applications. © 2014-IOS Press and the authors. All rights reserved.Ítem Solución de problemas literales(Universidad EAFIT, 2015) Esteban Duarte, Pedro Vicente; Esteban Duarte, Pedro Vicente. Universidad EAFIT, Escuela de Ciencias, Ciencias Básicas, Medellín, Colombia; Proyecto 50En todas las ciencias se presentan diversos problemas que deben ser planteados y resueltos -- Para el planteamiento de un problema se requiere conocer el contexto, las condiciones en las que es válido y, además, formularlo en un lenguaje adecuado, para que pueda ser comprendido por personas interesadas en el mismo -- Para la solución, es necesario el conocimiento de los términos en los que está planteado, hacer analogías con problemas similares, definir las variables necesarias, utilizar correctamente las fórmulas requeridas, validar la solución y utilizar la respuesta en la situación planteada para tener una mejor comprensión de ella -- La solución de problemas es una destreza que se adquiere con la práctica y la utilización adecuada de los conocimientos adquiridos en distintos cursos y actividades propias del contextoÍtem Universal quantum gates Via Yang-baxterization of dihedral quantum double(SPRINGER, 2007-01-01) Velez, Mario; Ospina, Juan; Velez, Mario; Ospina, Juan; Universidad EAFIT. Departamento de Ciencias; Lógica y ComputaciónThe recently discovered Yang-Baxterization process for the quantum double of the dihedral group algebra, is presented keeping on mind the quantum computation. The products resultant from Yang-Baxterization process are interpreted as universal quantum gates using the Bryslinski's theorem. Results are obtained for two-qubits and two-qutrits gates. Using the Zhang-Kauffman-Ge method (ZKGM), certain Hamiltonians responsible for the quantum evolution of the quantum gates are obtained. Possible physical systems such as anyons systems are mentioned as referents for practical implementation. © Springer-Verlag Berlin Heidelberg 2007.