Colecciones Institucionales

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Browsing Colecciones Institucionales by browse.metadata.categoria "Administración"

Now showing 1 - 20 of 315
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    A competency-based model for construction supervisors in developing countries
    (2007) Ferrada Calvo, Ximena Verónica
    Purpose - To analyze the role of construction site supervisors, including foremen and general foremen, as front-line managers. The role is treated as a critical labor function and a source of value-added for construction management.||Design/methodology/approach - An original model based on the labor competency management framework is proposed for training, developing and certifying construction supervisors in Chile and other developing countries. This model was developed from the findings of a case study in which the competency framework was applied to a specific construction company.||Findings - This case study has demonstrated the significant potential of the competency framework for the Chilean construction sector, with its underdeveloped human resources management methods. In particular, this framework can be an effective approach to achieving the competencies required by construction site supervisors who must deal with inadequately trained workers, as is the case in many developing countries. The structured approach of the competency framework can help companies create more objective schemes for the design and implementation of training programs.||Practical implications - The application of the competency approach can greatly improve the human resources management function in construction companies as well as the site performance of their personnel. The findings obtained so far in Chile can also be projected to construction companies in other developing countries in the region.||Originality/value - This paper presents the first application of the competency framework to a Chilean construction company. This study is also original in the sense that the application described here was carried out in an environment where human resource conditions are quite deficient.
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    A dominance solvable global game with strategic substitutes
    (2015) Harrison Vergara, Rodrigo José; Jara, P.
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    A Kinetic Study of Furan Formation in Wheat Flour-Based Model Systems during Frying
    (2017) Mariotti Celis, Maria S.; Zúñiga, Rommy N.; Cortés, Pablo; Pedreschi Plasencia, Franco
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    A Lessons-learned System for Construction Project Management: A Preliminary Application
    (2016) Ferrada Calvo, Ximena Verónica; Nuñez, D.; Neyem, Andrés; Serpell, A.; Sepúlveda Fernández, Marcos Ernesto
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    A long panel survey to elicit variation in preferences and attitudes in the choice of electric vehicles
    (2014) Jensen, A.; Cherchi, E.; Ortúzar Salas, Juan de Dios; CEDEUS (Chile)
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    A mixed integer programming approach to multi-skilled workforce scheduling
    (2016) Cuevas, R.; Ferrer Ortiz, Juan Carlos; Klapp Belmar, Mathias; Muñoz Abogabir, Juan Carlos
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    A Multi-criteria Approach for Team Recommendation
    (2017) Arias, Michael; Muñoz Gama, Jorge; Sepúlveda Fernández, Marcos Ernesto
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    A performance agreement to align the operation of a loading dock and a fleet.
    (1998) Donoso Ibáñez, Patricio; Singer González, Marcos Johanan; Scheller-Wolf, Alan
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    A pie de foto.
    (2007) Quintanilla Chala, José
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    A real options application to manage risk related to intrinsic variables of a mine plan : a case study on Chuquicamata U.G. project
    (2012) Castillo, María Fernanda del; Botin, J. A.; Pontificia Universidad Católica de Chile. Escuela de Ingeniería
    Los métodos tradicionales de cuantificación de riesgo proporcionan muy poca información sobre el origen del riesgo, y tienden a producir evaluaciones estáticas y sobre-conservadoras, que no tienen en cuenta los cambios que pueden producirse en el rendimiento económico del proyecto. Las decisiones de inversión en grandes proyectos mineros requieren modelos de evaluación de riesgo más complejo, que incluya el valor de la flexibilidad, y los distintos niveles de riesgo asociados a la incertidumbre en las variables del proyecto, como el precio, la ley del mineral, la dilución, la capacidad de producción, etc. En este contexto, los métodos de evaluación mediante Opciones Reales tienen probado potencial para cuantificar el riesgo asociado con dichas variables, e integrar en el proceso de evaluación el valor de escenarios alternativos y estrategias de gestión. En este estudio, se desarrolla un modelo de cuantificación de riesgo que logra cuantificar de forma exitosa el riesgo asociado a la dilución de una mina, como función del ritmo de producción. Este modelo es validado en un caso de estudio del Proyecto Chuquicamata Subterránea.
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    A risk-constrained project portfolio in centralized transmission expansion planning
    (2017) Molina, J.; Contreras, J.; Rudnick Van de Wyngard, Henry
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    A Systematic Approach for Evaluating Innovation Management in Construction Companies
    (2014) Serpell Bley, Alfredo; Álvarez Parra, Romina Vanesa
    The increasing competition within the construction industry has created a growing concern for innovation, being appreciated as an important lever for competitive advantage. However, despite its need, there are some critical barriers that make innovation in construction very difficult. In addition, the perceived risk of innovation is almost unacceptable to the sector's culture. These factors limit the innovation efforts being made. Thus, appropriate mechanisms are needed to overcome these limitations and propose actions to promote innovation and innovation management in constructions' firms. The aim of this paper is to describe an approach to innovation management that includes a system for evaluating the status of innovation management in construction companies (SEGi by its acronym in Spanish), i.e., all activities undertaken by a company to integrate innovation opportunities to improve its performance. The system has been structured based on both quantitative and qualitative methods, whose application allows evaluating the state of innovation management and generating proposals for actions to solve the detected limitations. The research methodology is described together with the development of the system for evaluating innovation management, the results of the study of three construction companies that participated in the application of the system and the main conclusions of the study. The proposed evaluation system can be used to promote the development and improvement of innovation capabilities within construction companies. Additional results of the study are the identification of six major innovation drivers that are important for construction companies. (C) 2014 The Authors. Published by Elsevier Ltd. This is an open access article under he CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).
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    Algoritmos genéticos para planificar la secuencia, asignación, tamaño y cantidad de lotes en una planta multi-producto
    (2014) Castillo Zunino, Francisco Javier; Gazmuri S., Pedro; Pontificia Universidad Católica de Chile. Escuela de Ingeniería
    Planificar la producción es de vital importancia en el mercado altamente competitivo, ya que mejora la eficiencia productiva. Las empresas han aumentado su interés en los softwares de planificación, y así mismo, se ha incentivado la investigación en el área. La producción por lotes es un tipo de manufactura ampliamente estudiado en la literatura. Este es un problema complejo, donde se requiere definir cuántos lotes habrá, su tamaño, qué maquinaria usarán y en qué orden serán producidos. Existen diversas formas de hacer esto, desde heurísticas simples hasta sofisticados métodos de optimización. Uno de estos métodos son los algoritmos genéticos, que basándose en la lógica evolutiva, realizan búsquedas al seleccionar, mutar y cruzar/mezclar soluciones. Estos algoritmos se suelen utilizar para secuenciar lotes, pero no para decidir cuántos lotes habrá, ni tampoco su tamaño; sino que reciben esta información como un dato. Por este motivo, esta tesis busca implementar un algoritmo genético capaz de incorporar estas variables de decisión, obteniendo buenos resultados.Se implementaron tres variantes del algoritmo genético, donde el primero realiza un crossover basado en aristas, el segundo, en la posición de los lotes y el último es una mutación guiada. Ellos se comparan con un algoritmo simulated annealing, una búsqueda totalmente aleatoria y un algoritmo genético modificado que no cuenta con crossover. Los resultados indican que los algoritmos genéticos sí son capaces de resolver la producción por lotes descrita a un bajo costo computacional, al obtener resultados mucho mejores que la búsqueda totalmente aleatoria. El crossover como mutación guiada obtiene los mejores resultados promedio en los 10 escenarios evaluados, cuando se minimiza el tiempo total de producción en búsquedas breves. También fue el mejor en 9 de los mismos 10 escenarios al minimizar la cantidad de pedidos sin cumplir. Además, demuestra tener la convergencia más veloz y solo es vencido por el SA cuando se realizan búsquedas extensas de varias iteraciones.
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    Amino acids as modulators of the production of hydrogen sulfide in problematic wine fermentations.
    (2019) Paredes Martínez, María José Carolina; Bordeu Schwarze, Edmundo; Pontificia Universidad Católica de Chile. Facultad de Agronomía e Ingeniería Forestal
    All stages of winemaking can present problems, but alcoholic fermentation is, in particular, the stage with most complications. During wine fermentation some conditions can result in sluggish or stuck fermentations. The information provided by routine measurements has not been sufficient to detect and diagnose the state of the fermentation, and in case of paralization, rescue it on time. Hence, real-time monitoring of key variables, using advanced instrumentation, would anticipate problematic situations. Nitrogen is one of the most studied variables for sluggish or stuck fermentations. However, only a fraction of the available nitrogen is assimilated by the yeasts, constituted by ammonium ions and free α-amino acids. Nitrogen compounds have also been associated to be key factors in volatile compounds formation, including hydrogen sulfide (H2S). Sulfide release during winemaking is a longstanding and serious problem. H2S is a malodorous compound with a low sensory threshold. It’s produced as metabolic requirement of yeast for synthesizing sulphur compounds. Its formation is carried out by the sulfate reduction pathway starting from organic and inorganic sources, such as sulfites, cysteine, and glutathione. The role of amino acids and ammonium on H2S formation has shown a high variability. Individual yeast nitrogen requirements, as well as its assimilation capacity of nitrogen compounds, together with the time nitrogen is supplemented during fermentation, are oenological factors that influence sulfide formation. Furthermore, yeast variability in sulfide metabolic regulation has also a major impact on H2S formation. Genetic variability, in the form of differential allelic expression controlling sulfide reduction pathway or adjacent routes, has been found to be a decisive trait that affects yeast capacity to produce H2S. However, this information hasn’t been able to help predict and control sulfide formation through alcoholic fermentation. Considering the above, in this research nitrogen, specifically its organic sources, is studied, as regulator of H2S formation. For this, the evolution of amino acids profile during wine fermentation of Cabernet Sauvignon must was measured. Two problematic fermentations conditions were evaluated, high initial sugar concentration and low initial assimilable nitrogen content, besides the standard winery condition, with four commercial wine yeast. Samples were collected at 24 hours intervals until the maximum amount of H2S was produced. Amino acids were evaluated by HPLC (High Performance Liquid Chromatography), allowing their quantification. A colorimetric method was exclusively developed to accurately quantify H2S production. Depending on the initial condition of the fermentation some amino acid showed a characteristic evolution profile, distinctive to each yeast. Most importantly, a unique H2S release patron was established for each wine yeast in relation to the starting conditions of the must fermentation.