Browsing by Author "Pozo, David"
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- ItemA convex chance-constrained model for reactive power planning(2015) Lopez, Julio; Pozo, David; Contreras, Javier; Mantovani, J. R. S.
- ItemA Three-Level Static MILP Model for Generation and Transmission Expansion Planning(2013) Pozo, David; Sauma Santis, Enzo Enrique; Contreras, Javier
- ItemAdmission planning in health care : stochastic and hierarchical approaches(2020) Germán, Ana Batista; Vera Andreo, Jorge; Pozo, David; Pontificia Universidad Católica de Chile. Escuela de IngenieríaEl sistema de salud es una industria de servicios que requiere planificación de calidad debido a la relevancia en sus operaciones. En particular, los hospitales públicos enfrentan presión constante para ser eficientes. Un proceso clave que gestiona las operaciones hospitalarias es la planificación de admisiones, que tiene como objetivo garantizar acceso oportuno y uso eficiente de los recursos. Sin embargo, varias fuentes de incertidumbre y limitaciones de recursos desafían el logro de esos objetivos. Además, similar a muchas industrias, las decisiones de largo plazo del hospital se basan en planes agregados que deben cumplirse en el corto plazo, el cual está sujeto a incertidumbre. Dado que no se garantiza coordinación temporal, pueden surgir varias inconsistencias, como tiempos de espera innecesarios, rechazos e incluso muerte prematura de los pacientes. Esta tesis evalúa el problema de consistencia temporal en el problema de planificación de admisiones, el cual está sujeto a incertidumbre y limitado por la capacidad de camas. El problema radica en cómo desarrollar un plan táctico que considere el impacto de las decisiones operativas mientras que garantice su viabilidad. El objetivo principal es modelar y resolver un proceso jerárquico de toma de decisiones que integre los niveles táctico y operativo para mejorar la calidad del servicio y el uso eficiente de los recursos. La investigación contribuye a proporcionar marcos de decisión efectivos para resolver el problema de planificación de admisiones. Consideramos métodos de optimización bajo incertidumbre en múltiples etapas para mejorar la consistencia y coordinación de la planificación. Se desarrolla un enfoque bi-objetivo estocástico en dos etapas para estudiar las decisiones de asignación, considerando incertidumbre de la demanda y disponibilidad de camas y evaluar el trade-off entre la perspectiva del paciente y la del hospital. Dado que el acceso a información es limitado, también se propone un enfoque de optimización robusta distribucional adaptativa para estudiar decisiones de asignación y programación. Se considera información parcial distribucional del tiempo de estadía, modelado a través de una formulación mejorada para restricciones de tipo de tiempo de servicio. El enfoque permite evaluar la relación entre robustez y consistencia. Mediante extensos estudios numéricos y validaciones con datos reales, demostramos que se obtiene una planificación eficiente adoptando un marco de decisión estocástico jerárquico. El marco es capaz de minimizar las inconsistencias implicadas en la planificación de admisión. Se proporcionan lineamientos de gestión para planificación táctica-operativa.
- ItemBasic theoretical foundations and insights on bilevel models and their applications to power systems(2017) Pozo, David; Sauma Santis, Enzo Enrique; Contreras, Javier
- ItemCan cross-border transmission expansion lead to fair and stable cooperation? Northeast Asia case analysis(2019) Churkin, Andrey; Pozo, David; Bialek, Janusz; Korgin, Nikolay; Sauma Santis, Enzo Enrique
- ItemEnergy storage and transmission expansion planning : substitutes or complements?(2018) Bustos, Carlos; Sauma Santis, Enzo Enrique; De la Torre, Sebastián; Aguado, José A.; Contreras, Javier; Pozo, David
- ItemIf you build it, he will come : anticipative power transmission planning(2013) Pozo, David; Contreras, Javier; Sauma Santis, Enzo Enrique
- ItemImpact of network payment schemes on transmission expansion planning with variable renewable generation(2016) Bravo, D.; Sauma Santis, Enzo Enrique; Contreras, J.; de la Torre, S.; Aguado, J.; Pozo, David
- ItemImpacts of network expansion on generation capacity expansion(IEEE, 2014) Pozo, David; Sauma Santis, Enzo Enrique; Contreras, J.A pessimistic three-level equilibrium model for a market-based expansion of both transmission and generation is proposed. The lower (third) level models the market outcome; the intermediate (second) level models the equilibrium in generation capacity expansion by taking into account the outcomes of the market equilibrium at the third level. The upper (first) level models the expansion of the transmission network. The second and third levels are modeled as an Equilibrium Problem with Equilibrium Constraints (EPEC) parameterized in terms of the optimal decisions of the transmission planner. This three-level hierarchy is motivated by the fact that transmission planners should consider expansions in generation that may take place, as well as the clearing of the market related to generation expansion, in order to make their decisions. At the first level, the transmission planner can take different positions with different impacts in the system because a manifold of equilibria is possible with different costs for the system. Unlike previously reported hierarchical approaches, which are implicitly formulated as optimistic, we solve the pessimistic solution of the problem (the transmission planner takes a pessimistic attitude towards the outcome of the generation expansion equilibrium). Results for a test power system are presented in order to show the efficiency and interpretations of the proposed model.
- ItemManipulability of Cost and Benefit Allocation in Cross-border Electrical Interconnection Projects(IEEE, 2019) Churkin, A.; Pozo, David; Bialek, J.; Korgin, N.; Sauma Santis, Enzo EnriqueCross-border electrical interconnection projects are getting more attention all over the world. In this context, cost-benefit allocation is especially important due to the need for fair sharing of power trading benefits among the countries as well as allocating the investments in capital-intensive power lines. One convenient way of dealing with these issues is using cooperative game theory. However, even fair allocation methods, such as the Shapley value, do not guarantee the stability of negotiations on cross-border interconnection projects. The result of the allocation process strongly depends on the individual system's data provided by each party involved. In this regard, the parties could have incentives to strategically provide data that would benefit themselves in the cost-benefit allocation process, potentially hindering the stability of the coalition. In this paper, we address the negotiation stability issues in terms of players strategic behavior and manipulability of cost-benefit allocation rules.
- ItemMulti-objective admission planning problem : a two-stage stochastic approach(2020) Germán, Ana Batista; Vera Andreo, Jorge; Pozo, David
- ItemReliable Renewable Generation and Transmission Expansion Planning: Co-Optimizing System's Resources for Meeting Renewable Targets(2017) Moreira, Alexandre; Pozo, David; Street, Alexandre; Sauma Santis, Enzo Enrique
- ItemRisk-constrained dynamic energy allocation for a wind power producer(2014) González, Virginia; Pozo, David; Contreras, Javier
- ItemRobust unit commitment with n-1 security criteria(2016) Gourtani, Arash; Xu, Huifu; Pozo, David; Nguyen, Tri-Dung
- ItemStochastic Time-of-Use-Type Constraints for Uninterruptible Services(IEEE, 2020) Batista German, Ana; Pozo, David; Vera Andreo, JorgeIn this paper, a mixed integer linear formulation for problems considering time-of-use-type constraints for uninterruptible services is presented. This paper is motivated by demand response (DR) problems in power systems, in which certain devices must remain online once they are switched on, along with a certain number of periods. Classically, this kind of constraints are modeled as a summation over a rolling time windows. This makes it difficult to consider this time-of-use parameter as uncertain. We propose an alternative formulation in which the time of use is on the right-hand side of a constraint instead on the limit of a summation. This allows applying existing stochastic optimization methodologies easily. An illustrative model for the optimal allocation of an uninterruptible load for the DR problem supports the proposed formulation.
- ItemUnit Commitment With Ideal and Generic Energy Storage Units(2014) Pozo, David; Contreras, J.; Sauma Santis, Enzo Enrique
- ItemWhen doing nothing may be the best investment action: Pessimistic anticipative power transmission planning(2017) Pozo, David; Sauma Santis, Enzo Enrique; Contreras, Javier