4 research outputs found
Optimal allocation of airplanes to routes
No full textIn this paper, we introduce a model that can assist airline planners in deploying their fleets as efficiently as possible. Specifically, we outline an optimization model that assigns a fleet of aircraft of different types to routes to maximize profits. An algorithm for solving nonlinear transportation problem is suggested. It is based on the use of Lagrange multipliers. We define and illustrate the use of the loss function, the cost structure of which is piecewise linear. The necessary and sufficient conditions for optimality are given. To illustrate the proposed approach, a numerical example is given.
First Published Online: 14 Oct 201
Optimal airline seat inventory control for multi‐leg flights
No full textAirline seat inventory control is about “selling the right seats to the right people at the right time”. In this paper, the problem of determining optimal booking policy for multiple fare classes in a pool of identical seats for multi‐leg flights is considered. During the time prior to departure of a multi‐leg flight, decisions must be made concerning the allocation of reserved seats to passengers requesting space on the full or partial spans of the flight. It will be noted that in the case of multi‐leg flights the long‐haul passengers are often unable to obtain seats because the shorter‐haul passengers block them. For large commercial airlines, efficiently setting and updating seat allocation targets for each passenger category on each multi‐leg flight is an extremely difficult problem. This paper presents static and dynamic models of airline seat inventory control for multi‐leg flights with multiple fare classes, which allow one to maximize the expected contribution to profit. The dynamic model uses the most recent demand and capacity information and allows one to allocate seats dynamically and anticipatorily over time.
First Published Online: 14 Oct 201
Inclusive Innovation Systems Emergence: Contributions to their understanding through agent-based modeling
No full textLos sistemas de innovación inclusivos tienen como propósito aportar a la reducción de la exclusión social a través de la innovación. Comprender cómo funciona este tipo de sistemas es de gran interés en las agendas de investigación de los países del Sur Global, dado los altos índices de problemas sociales que caracterizan la región. Una forma de aportar a dicha comprensión es explicando cómo emergen estos sistemas; propósito que se aborda en esta tesis de manera evolutiva, a través de la Modelación Basada en Agentes. Se creó un modelo a partir de bases teóricas sobre sistemas de innovación, innovación inclusiva, nuevos agentes y sus relaciones, procesos de enseñanza aprendizaje, tipos de conocimiento, direccionalidad, capacidades de innovación y capacidades para la inclusión; elementos relevantes en los sistemas de innovación inclusivos. El modelo fue validado en el sector agropecuario del municipio de La Unión, Colombia y permite simular diferentes escenarios que representan los sistemas de innovación convencionales y diferentes configuraciones de sistemas de innovación inclusivos. Mediante el análisis de seis escenarios se pudo concluir que la direccionalidad de los agentes juega un papel importante para detonar la emergencia de un sistema de innovación inclusivo; sumado a esto, es importante que existan agentes con capacidades de innovación y capacidades para la inclusión que se complementen, de tal forma que se pueda propiciar la participación de los excluidos en las dinámicas de innovación y la apropiación tanto del conocimiento científico y tecnológico como el conocimiento tradicional. Esto conlleva a propiciar el fortalecimiento de los agentes con las capacidades de vinculación social, como lo es el intermediario inclusivo, con el objeto de poder lograr un sistema balanceado, es decir, que existan agentes con las diferentes capacidades requeridas para resolver y/o aprovechar las necesidades, oportunidades de innovación, problemas e ideas que determinan un entorno inclusivo (Texto tomado de la fuente)The purpose of inclusive innovation systems is to contribute to reduce of social exclusion through innovation. Understanding how this type of system works is of great interest in the research agendas of the Global South countries, given the high rates of social problems that characterize the region. One way to contribute to this understanding is by explaining how these systems emerge; purpose that is addressed in this thesis in an evolutionary way, through Agent-Based Modeling. A model was created based on theoretical background on innovation systems, inclusive innovation, new agents and their relationships, teaching-learning processes, types of knowledge, directionalities, innovation capabilities and capabilities for inclusion; all of them are relevant elements in inclusive innovation systems. The model was validated in the agricultural sector of the municipality of La Unión, Colombia and allows simulating different scenarios to represent conventional innovation systems and different configurations of inclusive innovation systems. Through the analysis of six scenarios, it was possible to conclude that the directionality of the agents plays an important role in triggering the emergence of an inclusive innovation system; added to this, it is important that there are agents with innovation capacities and capacities for inclusion that complement each other, in such a way the participation of the excluded in innovation dynamics and the appropriation of both scientific and technological knowledge like traditional knowledge can be promoted. This leads to promoting the strengthening of agents with the capacities of social connection, such as the inclusive intermediary, in order to be able to achieve a balanced system, that is, it is necessary agents with different capacities exists to solve and/or take advantage of the needs, innovation opportunities, problems and ideas that determine an inclusive environmentMinisterio de Ciencia Tecnología e Innovación de Colombia - MincienciasEste documento recopila varias publicaciones realizadas durante el doctorado, las cuales se señalan en el documentoDoctoradoDoctor en IngenieríaModelación Basada en AgentesWalter Lugo Ruiz CastañedaÁrea Curricular de Ingeniería Administrativa e Ingeniería Industria
