The location routing problem with facility sizing decisions

The location routing problem (LRP) integrates operational decisions on vehicle routing operations with strategic decisions on the location of the facilities or depots from which the distribution will take place. In other words, it combines the well-known vehicle routing problem (VRP) with the facility location problem (FLP). Hence, the LRP is an NP-hard combinatorial optimization problem, which justifies the use of metaheuristic approaches whenever large-scale instances need to be solved. In this paper, we explore a realistic version of the LRP in which facilities of different capacities are considered, i.e., the manager has to consider not only the location but also the size of the facilities to open. In order to tackle this optimization problem, three mixed-integer linear formulations are proposed and compared. As expected, they have been proved to be cost- and time- inefficient. Hence, a biased-randomized iterated local search algorithm is proposed. Classical instances for the LRP with homogeneous facilities are naturally extended to test the performance of our approach.Peer ReviewedPostprint (published version

Combining heuristics with simulation and fuzzy logic to solve a flexible-size location routing problem under uncertainty

The location routing problem integrates both a facility location and a vehicle routing problem. Each of these problems are NP-hard in nature, which justifies the use of heuristic-based algorithms when dealing with large-scale instances that need to be solved in reasonable computing times. This paper discusses a realistic variant of the problem that considers facilities of different sizes and two types of uncertainty conditions. In particular, we assume that some customers’ demands are stochastic, while others follow a fuzzy pattern. An iterated local search metaheuristic is integrated with simulation and fuzzy logic to solve the aforementioned problem, and a series of computational experiments are run to illustrate the potential of the proposed algorithm.This work has been partially supported by the Spanish Ministry of Science (PID2019-111100RB-C21/AEI/10.13039/501100011033). In addition, it has received the support of the Doctoral School at the Universitat Oberta de Catalunya (Spain) and the Universidad de La Sabana (INGPhD-12-2020).Peer ReviewedPostprint (published version

Incorporating biodiversity responses to land use change scenarios for preventing emerging zoonotic diseases in areas of unknown host-pathogen interactions

The need to reconcile food production, the safeguarding of nature, and the protection of public health is imperative in a world of continuing global change, particularly in the context of risks of emerging zoonotic disease (EZD). In this paper, we explored potential land use strategies to reduce EZD risks using a landscape approach. We focused on strategies for cases where the dynamics of pathogen transmission among species were poorly known and the ideas of “land-use induced spillover” and “landscape immunity” could be used very broadly. We first modeled three different land-use change scenarios in a region of transition between the Cerrado and the Atlantic Forest biodiversity hotspots. The land-use strategies used to build our scenarios reflected different proportions of native vegetation cover, as a proxy of habitat availability. We then evaluated the effects of the proportion of native vegetation cover on the occupancy probability of a group of mammal species and analyzed how the different land-use scenarios might affect the distribution of species in the landscape and thus the risk of EZD. We demonstrate that these approaches can help identify potential future EZD risks, and can thus be used as decision-making tools by stakeholders, with direct implications for improving both environmental and socio-economic outcomes

Global collision-risk hotspots of marine traffic and the world’s largest fish, the whale shark

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Womersley, F. C., Humphries, N. E., Queiroz, N., Vedor, M., da Costa, I., Furtado, M., Tyminski, J. P., Abrantes, K., Araujo, G., Bach, S. S., Barnett, A., Berumen, M. L., Bessudo Lion, S., Braun, C. D., Clingham, E., Cochran, J. E. M., de la Parra, R., Diamant, S., Dove, A. D. M., Dudgeon, C. L., Erdmann, M. V., Espinoza, E., Fitzpatrick, R., González Cano, J., Green, J. R., Guzman, H. M., Hardenstine, R., Hasan, A., Hazin, F. H. V., Hearn, A. R., Hueter, R. E., Jaidah, M. Y., Labaja, J., Ladinol, F., Macena, B. C. L., Morris Jr., J. J., Norman, B. M., Peñaherrera-Palmav, C., Pierce, S. J., Quintero, L. M., Ramırez-Macías, D., Reynolds, S. D., Richardson, A. J., Robinson, D. P., Rohner, C. A., Rowat, D. R. L., Sheaves, M., Shivji, M. S., Sianipar, A. B., Skomal, G. B., Soler, G., Syakurachman, I., Thorrold, S. R., Webb, D. H., Wetherbee, B. M., White, T. D., Clavelle, T., Kroodsma, D. A., Thums, M., Ferreira, L. C., Meekan, M. G., Arrowsmith, L. M., Lester, E. K., Meyers, M. M., Peel, L. R., Sequeira, A. M. M., Eguıluz, V. M., Duarte, C. M., & Sims, D. W. Global collision-risk hotspots of marine traffic and the world’s largest fish, the whale shark. Proceedings of the National Academy of Sciences of the United States of America, 119(20), (2022): e2117440119, https://doi.org/10.1073/pnas.2117440119.Marine traffic is increasing globally yet collisions with endangered megafauna such as whales, sea turtles, and planktivorous sharks go largely undetected or unreported. Collisions leading to mortality can have population-level consequences for endangered species. Hence, identifying simultaneous space use of megafauna and shipping throughout ranges may reveal as-yet-unknown spatial targets requiring conservation. However, global studies tracking megafauna and shipping occurrences are lacking. Here we combine satellite-tracked movements of the whale shark, Rhincodon typus, and vessel activity to show that 92% of sharks’ horizontal space use and nearly 50% of vertical space use overlap with persistent large vessel (>300 gross tons) traffic. Collision-risk estimates correlated with reported whale shark mortality from ship strikes, indicating higher mortality in areas with greatest overlap. Hotspots of potential collision risk were evident in all major oceans, predominantly from overlap with cargo and tanker vessels, and were concentrated in gulf regions, where dense traffic co-occurred with seasonal shark movements. Nearly a third of whale shark hotspots overlapped with the highest collision-risk areas, with the last known locations of tracked sharks coinciding with busier shipping routes more often than expected. Depth-recording tags provided evidence for sinking, likely dead, whale sharks, suggesting substantial “cryptic” lethal ship strikes are possible, which could explain why whale shark population declines continue despite international protection and low fishing-induced mortality. Mitigation measures to reduce ship-strike risk should be considered to conserve this species and other ocean giants that are likely experiencing similar impacts from growing global vessel traffic.Funding for data analysis was provided by the UK Natural Environment Research Council (NERC) through a University of Southampton INSPIRE DTP PhD Studentship to F.C.W. Additional funding for data analysis was provided by NERC Discovery Science (NE/R00997/X/1) and the European Research Council (ERC-AdG-2019 883583 OCEAN DEOXYFISH) to D.W.S., Fundação para a Ciência e a Tecnologia (FCT) under PTDC/BIA/28855/2017 and COMPETE POCI-01–0145-FEDER-028855, and MARINFO–NORTE-01–0145-FEDER-000031 (funded by Norte Portugal Regional Operational Program [NORTE2020] under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund–ERDF) to N.Q. FCT also supported N.Q. (CEECIND/02857/2018) and M.V. (PTDC/BIA-COM/28855/2017). D.W.S. was supported by a Marine Biological Association Senior Research Fellowship. All tagging procedures were approved by institutional ethical review bodies and complied with all relevant ethical regulations in the jurisdictions in which they were performed. Details for individual research teams are given in SI Appendix, section 8. Full acknowledgments for tagging and field research are given in SI Appendix, section 7. This research is part of the Global Shark Movement Project (https://www.globalsharkmovement.org)

Global Spatial Risk Assessment of Sharks Under the Footprint of Fisheries

Effective ocean management and conservation of highly migratory species depends on resolving overlap between animal movements and distributions and fishing effort. Yet, this information is lacking at a global scale. Here we show, using a big-data approach combining satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively) and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of high-seas fishing effort. Results demonstrate an urgent need for conservation and management measures at high-seas shark hotspots and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real time, dynamic management

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Innovación, desarrollo tecnológico y gestión : una construcción desde la investigación

Libro que compila investigaciones de carácter aplicadas y descriptivas en materia de innovación y desarrollo tecnológico, gestión organizacional y empresarial orientada a productividad, rentabilidad, competitividad y sostenibilidadBook that compiles researches of applied and descriptive character in the matter of innovation and technological development, organizational and business management oriented to productivity, profitability, competitiveness and sustainabilityCapítulo 1. Material compuesto para la construcción a partir de la celulosa del papel y cartón reciclado / Carlos Arturo Tamayo S; Nicolás Montero Camacho; Fredy Antonio Herrera -- Capítulo 2. Tecnologías de conservación para base de sopa de frijol rojo (phaseolus vulgaris) y vegetales / Yaceris Castro Escorcia; Teresa Altamar Pérez; Enedys Florez Cortés; Ángela Ortiz Ruiz. Capítulo 3. Utilización de harina compuesta de frijol caupi (vigna unguiculata) en masas para alimentos congelados / Marcela Villalba Cadavid; Matilde Rodríguez Muñoz; Beatriz Fernández; Juan Mendoza Combatt -- Capítulo 4. Elaboración de biorrecubrimiento comestible para carne de hamburguesa como alternativa de conservación y condimento natural / Camila Andrea Ubaque Beltrán. CAPÍTULO 5. Identificación de alternativas de industrialización de productos y subproductos agroindustriales en nuevos materiales bio poliméricos / Luz Henao Díaz; Deya Pérez Zúñiga; Herold Arango Gómez. Capítulo 6. SCADA inalámbrico para monitoreo de sistemas de energía solar / Nelson Giovanni Agudelo Cristancho; Juan Carlos Amezquita Tovar; Ángela María Montoya Castro. -- Capítulo 7. Evaluación de la calidad del agua para consumo humano del corregimiento de Jaraquiel, Montería, Córdoba / Carlos Burgos Galeano; Álvaro Aleán Vásquez; Paula Estrada Palencia -- Capítulo 8. Optimización del sistema de abastecimiento de agua en la comunidad de Jaraquel, Montería Colombia / Carlos Burgos Galeano; Pedro Ramos Tejada; Paula Estrada Palencia; Jhon Sánchez Correa. -- Capítulo 9. Ejecución y sostenibilidad de proyectos productivos en la microrregión cafetera del municipio de Ciénaga, Magdalena / Sugey Issa Fontalvo; Eduardo Robles Panetta; Freddy González Castillo. -- Capítulo 10. Aplicación del método cualitativo por puntos para determinar aspirante favorito a cargos directivos en IES / Zamir Martelo Ballesteros; Raúl Martelo Gómez; Luis Tovar Garrido; Natividad Villabona Gómez; David Franco Borré. -- Capítulo 11 Responsabilidad social en comunidades indígenas orientada al diseño de automatización de válvulas del gasoducto Riohacha-Maicao / Gelvis Melo Freile; César Rivera Romero; Jesús García Guiliany. -- Capítulo 12 Fortalecimiento de la gestión económica de las Mipymes a través de la consultoría / Gloria Amparo Acosta Romero; Mónica Andrade Ríos; Karen Roxana Sánchez. -- Capítulo 13. El compromiso como valor en la responsabilidad social universitaria / Maura Quintero Gutiérrez, Dubys Villarreal Torres; Jesús García Guiliany; Annherys Paz Marcano; Marieth Orcasitas Peñaloza. -- Capítulo 14. Educación financiera como alternativa de desarrollo económico y social para el distrito de Riohacha / Henitzo Martínez Pinedo; Darcy Luz Mendoza; Martha Jaramillo Acosta; Edwin Salas Solano. -- Capítulo 15. Tecnologías de información y comunicación en proceso contable y financiero en pymes del sector turístico / Martha Josefina Castrillón Rois; Edilberto Rafael Santos Moreno; Lorena Esther Gómez Bermúdez; Génesis Barros González. -- Capítulo 16. Aplicación de brainstorming y problem trees para determinar factores que inciden en enseñanza del inglés / Jesús Llerena; Raúl J. Martelo; Jhon Cuesta; Javier Pinedo; David Franco.-- Capítulo 17. Incidencia del marketing en las microempresas del sector comercio en Rionegro Antioquia: conceptualización / Santiago Álzate Carmona; María Yamile Mazo Gil; Leidy García Jaramillo. -- Capítulo 18. Turismo en el Cabo de la Vela: un acercamiento entre los imaginarios turísticos de los visitantes y la creencia de Jepirra, territorio sagrado / María Laura Aponte Aarón; Esmerlis Camargo Torres. -- Capítulo 19. Caracterización de la actividad turística en buenaventura y su integración con las comunidades locales / Víctor Cándelo Aragón; Henry Orobio García; Luis Montaño Aguilar. -- Capítulo 20. Plataforma de comercialización electrónica de un centro de abastos / Karen Ávila Suarez; Mauro Reyes Ortiz. -- Capítulo 21. El teletrabajo en la gestión administrativa / Estefanía Sandoval Cruz; René Alexander Guerrero Vergel. -- Capítulo 22. Gestión del conocimiento y alianzas estratégicas en los procesos de innovación tecnológica / Elder Rivero Gutiérrez; Fátima Bolaño Mendoza. -- Capítulo 23. Competitividad e innovación en el aprendiz SENA: perspectivas de formación / Elizabeth Tuberquia Vanegas; René Alexander Guerrero Vergel. -- Capítulo 24. Bomba de riego por goteo solar, una alternativa para aumentar la eficiencia energética en las unidades acuícolas / Sergio Gabriel Brito Brito; Daldo Ricardo Araujo Vidal; Nicolás Annicharico Jiménez. -- Capítulo 25. Herramienta digital de consultas contables y tributarias para unidades productivas creadas en el fondo emprender / Elkin Fuentes Jiménez; Alda Pérez Campuzano; Marieth Orcasitas Peñaloza; Olga Elena Guerra ArmentaPrimera ediciónna347 página

A simheuristic algorithm for the capacitated location routing problem with stochastic demands

19 páginasThe capacitated location routing problem (CLRP) integrates a facility location problem with a multi-depot vehicle routing problem. We consider the CLRP with stochastic demands, whose specific values are only revealed upon reaching each customer. The main goal is to minimise the expected costs of: (i) opening facilities, (ii) using a fleet of vehicles, (iii) executing a routing plan, and (iv) applying corrective actions. The latter are required whenever a route failure occurs due to unexpected high demands. We propose a simheuristic algorithm hybridizing simulation with an iterated local search metaheuristic, aimed at: (i) proposing a safety-stock policy to diminish the likelihood of route failure; and, (ii) estimating the expected cost and the reliability of each “elite” solution. We assess our approach on classical CLRP benchmarks, which are later extended to consider demand uncertainty. Finally, we also discuss the effects of the safety-stock policy on costs and reliability

Consolidation centers in city logistics A cooperative approach based on the location routing problem

12 páginasAbstract: In the context of city logistics, freight transportation is one of the prominent causes of traffic congestion, high levels of pollution, and safety concerns. To decrease the negative impact of these issues, different methods have been traditionally implemented. On the one hand, the location of urban consolidation Centers (UCCs) near a city can be used to consolidate freight delivery services. Therefore, the number of trucks moving in urban areas can be reduced. On the other hand, Horizontal Cooperation can also help to reduce environmental impact while increasing service level. This paper combines both strategies, that is, we deal with the location of UCCs and, simultaneously, we analyze different scenarios where the players of different supply chain processes exhibit various levels of cooperation. Thus, different levels of cooperations regarding routing and UCCs-location decisions are considered in the following scenarios: (a) non-cooperative case, in which all decisions are decentralized (i.e., each enterprise solves its own vehicle routing problem); (b) low-cooperative case, where depot capacities are shared but the customers are still being served by each company's fleet of vehicles; (c) semi-cooperative case, based on centralized route planning decisions (i.e. facilities and fleets are shared among participating enterprises); and (d) fully cooperative scenario, where the routing plans and facility-location decisions are taken by consensus amongst all the participants. In order to estimate the benefits of both strategies, we propose a flexible metaheuristic algorithm to deal with the combined location and routing problem under the different cooperative scenarios. Our results show impressive benefits of the proposed approach