|2 julio, 2020|
|12:30 pm||a||1:30 pm|
Título: Gain-sharing in urban consolidation centers.
Ponente: Behzad Hezarkhani (Brunel University London, U.K.)
Organizador: Ana Meca
Fecha: Jueves 2 de julio a las 12:00 horas.
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Resumen: Urban consolidation centers provide the logistical infrastructure for cooperation among less-than-truckload carriers with contiguous destinations. The rising number of initiatives to establish and operate urban consolidation centers and their low success rates signal the need for better mechanisms to manage cooperation in this context. We introduce and study cooperative situations comprising a set of carriers with time sensitive deliveries who can consolidate their cargo to obtain savings. We introduce the class of Dispatch Consolidation (DC) games and search for ways to fairly allocate the obtained savings among the participating carriers. When delivery capacities are not restrictive, i.e.when waiting costs trigger truck dispatches, we show that stable allocations inthe core always exist and can, in their entirety, be found by solving a compact linear program. With restrictive capacities, however, the core of a DC game maybe come empty. We introduce the notion of component-wise core for DC games top reserve stability first and foremost among the carriers whose deliveries are dispatched together in the chosen optimal solutions. The novelty of our approach is to link the stability requirements of an allocation rule with the structure of selected solutions for the underlying optimization problems. We characterize the component-wise cores of DC games, prove their non-emptiness, and suggest proportionally calculated allocations therein.
Jesus T. Pastor (University Miguel Hernandez of Elche), C. A. Knox Lovell (University of Queensland) and Juan Aparicio (University Miguel Hernandez of Elche)
Abstract: A natural multiplicative efficiency measure for the Constant Returns to Scale proportional directional distance function (pDDF) is derived, relating its associated linear program to that of the well-known output-oriented radial efficiency measurement model. Based on this relationship, a traditional CCD (Caves, Christensen and Diewert) Malmquist index is introduced to show that, when it is based on the new efficiency measure associated with the pDDF, rather than on a radial efficiency measure associated with an oriented distance function, it becomes a Total Factor Productivity (TFP) index. This constitutes a new result, because heretofore the traditional CCD Malmquist index has not been considered a TFP index. Additionally, a new decomposition of the CCD Malmquist index is proposed that expresses productivity change as the ratio of two components, productivity change due to output change in the numerator and productivity change due to input change in the denominator. In an Appendix the efficiency measure is extended to include any returns to scale pDDF.
Keywords: Data envelopment analysis; Proportional directional distance function; Efficiency measure; Malmquist productivity index
Bogl ́arka G.-T ́oth (University of Szeged), Laura Anton-Sanchez (Miguel Hernández University), José Fernández (University of Murcia), Juana L. Redondo (University of Almería) and Pilar M. Ortigosa (University of Almería)
Abstract: A firm wants to expand its presence in a given geographical region. The available budget can be invested in opening a new facility and/or modifying the qualities of the existing firm-owned facilities. The firm can also close some of its existing facilities in order to invest the
money formerly devoted to them to its other facilities or to the new one (in case it is finally open). A MINLP formulation is proposed to model
this new problem. Both an exact interval branch-and-bound method and an ad-hoc heuristic are proposed to solve the model. Some computational results are reported
Keywords: Facility location; Competition; Quality; MINLP; Interval analysis; Heuristic
|22 junio, 2020|
|12:00 pm||a||1:00 pm|
Título: Investigando síntesis de programas en Python
Ponente: Guillem Durán (Fragile Technologies, Murcia)
Organizador: José Mª Amigó
Fecha: Lunes 22 de junio a las 12:00 horas.
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Resumen: La síntesis de programas consiste en construir modelos predictivos combinando diferentes bloques independientes que representan funciones matemáticas. El objetivo de esta charla es ofrecer una visión global de las herramientas y procesos necesarios para desarrollar un proyecto de investigación en Python, además de enseñar cómo se han aplicado en el ámbito de la síntesis de programas.
Virginica Rusu (Universidad de Playa Ancha), Cristian Rusu (Pontificia Universidad Católica de Valparaíso), Federico Botella (Universidad Miguel Hernández de Elche), Daniela Quiñones (Pontificia Universidad Católica de Valparaíso), Camila Bascur (Pontificia Universidad Católica de Valparaíso) and Virginia Zaraza Rusu (Pontificia Universidad Católica de Valparaíso).
Abstract: User eXperience (UX) and Usability are key concepts in Human-Computer Interaction (HCI). Customer eXperience (CX) is traditionally related to Service Science, but lately becomes a relevant topic in HCI. It offers a more comprehensive approach to the user as customer of several products, systems or services that a company offers. We focused for years our research on tourist as user of dedicated software systems and digital products. We are now focusing on tourist as customer, involving not only interactive software systems, but also the whole range of products and services that she or he interacts with. The paper examines CX as an extension of UX, and as a bridge between HCI and Service Science, focusing on tourist as customer.
Keywords: Customer experience; User experience; Service science; Tourism; Online travel agencies