2,976 research outputs found

    Selection of rail improvement projects using the Analytic Network Process

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    Trabajo presentado al XI International Symposium on the AHP celebrado en Nápoles (Italia) del 15 al 18 de Junio de 2011.In this artiele the applieation of the Analytie Network Process (ANP) to establish priorities arnong the portfolio of rail infrastructure rnaintenance, rehabilitation and improvernent projects in the area of Valencia (Spain) is presented. The problem is complex because of the large number and variety of projects to be considered and the great number of criteria that must be taken into account in the decision analysis process. The present work is a continuation of a previons research hased on the AHP model. The present study analyzes the different priority values of a particular group of projects obtained in ANP and AHP as well as changes in the weigbts of the criteria and the possibility of eliminating minor criteria from the model for the sake of simplicity.Peer Reviewe

    Testing a Recent DEMATEL-Based Proposal to Simplify the Use of ANP

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    [EN] The Analytic Network Process (ANP) is a well-known multi-criteria decision method that allows the relationships between its elements to be incorporated into the model. The large number of questions to be answered is one of the main drawbacks of the method, since it is time consuming for decision makers and experts who participate in the decision process. A recent DEMATEL-based ANP proposal can significantly reduce the number and the complexity of questions. This proposal was simply exposed and lacked an experimental test with real cases. The fundamental objective of this work is to answer the question: Does it work? In this work, this new proposal is applied to 45 ANP cases published in the literature. Variants to the verified proposal have also been identified. The results obtained show that the values of the priorities and the ranks obtained with this new proposal are very similar to the results obtained with the ANP, reducing the number of questions required by 42% on average. Additionally, in this work you can find the compilation of the 45 ANP weighted supermatrices to use in your investigations.Schulze-González, E.; Pastor-Ferrando, J.; Aragonés-Beltrán, P. (2021). Testing a Recent DEMATEL-Based Proposal to Simplify the Use of ANP. Mathematics. 9(14):1-23. https://doi.org/10.3390/math9141605S12391

    Selection of maintenance, renewal and improvement projects in rail lines using the analytic network process

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    [EN] This paper addresses one of the most common problems that a railway infrastructure manager has to face: to prioritise a portfolio of maintenance, renewal and improvement (MR&I) projects in a railway network. This decision-making problem is complex due to the large number of MR&I projects in the portfolio and the different criteria to take into consideration, most of which are influenced and interrelated to each other. To address this problem, the use of the analytic network process (ANP) is proposed. The method is applied to a case study in which the Local Manager of the public company, who is responsible for the MR&I of Spanish Rail Lines, has to select the MR&I projects which have to be executed first. Based on the results, it becomes evident that, for this case study, the main factor of preference for a project is the location of application rather than the type of project. The main contributions of this work are: the deep analysis done to identify and weigh the decision criteria, how to assess the alternatives and provide a rigorous and systematic decision-making process, based on an exhaustive revision of the literature and expertiseThe translation of this paper was funded by the Universitat Politecnica de Valencia.Montesinos-Valera, J.; Aragonés-Beltrán, P.; Pastor-Ferrando, J. (2017). Selection of maintenance, renewal and improvement projects in rail lines using the analytic network process. Structure and Infrastructure Engineering. 13(11):1476-1496. https://doi.org/10.1080/15732479.2017.1294189S147614961311Abril, M., Barber, F., Ingolotti, L., Salido, M. A., Tormos, P., & Lova, A. (2008). An assessment of railway capacity. Transportation Research Part E: Logistics and Transportation Review, 44(5), 774-806. doi:10.1016/j.tre.2007.04.001Ahern, A., & Anandarajah, G. (2007). Railway projects prioritisation for investment: Application of goal programming. Transport Policy, 14(1), 70-80. doi:10.1016/j.tranpol.2006.10.003Al-Harbi, K. M. A.-S. (2001). Application of the AHP in project management. International Journal of Project Management, 19(1), 19-27. doi:10.1016/s0263-7863(99)00038-1Aragonés-Beltrán, P., Chaparro-González, F., Pastor-Ferrando, J. P., & Rodríguez-Pozo, F. (2010). An ANP-based approach for the selection of photovoltaic solar power plant investment projects. Renewable and Sustainable Energy Reviews, 14(1), 249-264. doi:10.1016/j.rser.2009.07.012Aragonés-Beltrán, P., Chaparro-González, F., Pastor-Ferrando, J.-P., & Pla-Rubio, A. (2014). An AHP (Analytic Hierarchy Process)/ANP (Analytic Network Process)-based multi-criteria decision approach for the selection of solar-thermal power plant investment projects. Energy, 66, 222-238. doi:10.1016/j.energy.2013.12.016Arif, F., Bayraktar, M. E., & Chowdhury, A. G. (2016). 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Multiple Attribute Decision Making. Lecture Notes in Economics and Mathematical Systems. doi:10.1007/978-3-642-48318-9Ieda, H., Kanayama, Y., Ota, M., Yamazaki, T., & Okamura, T. (2001). How can the quality of rail services in Tokyo be further improved? Transport Policy, 8(2), 97-106. doi:10.1016/s0967-070x(01)00002-6Ishizaka, A., & Labib, A. (2011). Review of the main developments in the analytic hierarchy process. Expert Systems with Applications. doi:10.1016/j.eswa.2011.04.143Ishizaka, A., & Nemery, P. (2013). Multi-Criteria Decision Analysis. doi:10.1002/9781118644898Ivanović, I., Grujičić, D., Macura, D., Jović, J., & Bojović, N. (2013). One approach for road transport project selection. Transport Policy, 25, 22-29. doi:10.1016/j.tranpol.2012.10.001Johansson, P., & Nilsson, J.-E. (2004). An economic analysis of track maintenance costs. Transport Policy, 11(3), 277-286. doi:10.1016/j.tranpol.2003.12.002Kabir, G., Sadiq, R., & Tesfamariam, S. (2013). A review of multi-criteria decision-making methods for infrastructure management. Structure and Infrastructure Engineering, 10(9), 1176-1210. doi:10.1080/15732479.2013.795978Karanik, M., Wanderer, L., Gomez-Ruiz, J. A., & Pelaez, J. I. (2016). Reconstruction methods for AHP pairwise matrices: How reliable are they? Applied Mathematics and Computation, 279, 103-124. doi:10.1016/j.amc.2016.01.008Karydas, D. M., & Gifun, J. F. (2006). A method for the efficient prioritization of infrastructure renewal projects. Reliability Engineering & System Safety, 91(1), 84-99. doi:10.1016/j.ress.2004.11.016Kułakowski, K. (2015). Notes on order preservation and consistency in AHP. European Journal of Operational Research, 245(1), 333-337. doi:10.1016/j.ejor.2015.03.010Kumar, G., & Maiti, J. (2012). Modeling risk based maintenance using fuzzy analytic network process. Expert Systems with Applications, 39(11), 9946-9954. doi:10.1016/j.eswa.2012.01.004Lee, A. H. I., Chen, H. H., & Kang, H.-Y. (2009). Operations management of new project development: innovation, efficient, effective aspects. Journal of the Operational Research Society, 60(6), 797-809. doi:10.1057/palgrave.jors.2602605LEE, A. H. I., KANG, H.-Y., & CHANG, C.-C. (2011). AN INTEGRATED INTERPRETIVE STRUCTURAL MODELING–FUZZY ANALYTIC NETWORK PROCESS–BENEFITS, OPPORTUNITIES, COSTS AND RISKS MODEL FOR SELECTING TECHNOLOGIES. International Journal of Information Technology & Decision Making, 10(05), 843-871. doi:10.1142/s0219622011004592Liang, C., & Li, Q. (2008). Enterprise information system project selection with regard to BOCR. International Journal of Project Management, 26(8), 810-820. doi:10.1016/j.ijproman.2007.11.001Macharis, C., & Bernardini, A. (2015). Reviewing the use of Multi-Criteria Decision Analysis for the evaluation of transport projects: Time for a multi-actor approach. Transport Policy, 37, 177-186. doi:10.1016/j.tranpol.2014.11.002Mardani, A., Jusoh, A., & Zavadskas, E. K. (2015). Fuzzy multiple criteria decision-making techniques and applications – Two decades review from 1994 to 2014. Expert Systems with Applications, 42(8), 4126-4148. doi:10.1016/j.eswa.2015.01.003Medury, A., & Madanat, S. (2013). Incorporating network considerations into pavement management systems: A case for approximate dynamic programming. Transportation Research Part C: Emerging Technologies, 33, 134-150. doi:10.1016/j.trc.2013.03.003Millet, I., & Saaty, T. L. (2000). On the relativity of relative measures – accommodating both rank preservation and rank reversals in the AHP. European Journal of Operational Research, 121(1), 205-212. doi:10.1016/s0377-2217(99)00040-5Nyström, B., & Söderholm, P. (2010). Selection of maintenance actions using the analytic hierarchy process (AHP): decision-making in railway infrastructure. Structure and Infrastructure Engineering, 6(4), 467-479. doi:10.1080/15732470801990209Olsson, N. O. E., Økland, A., & Halvorsen, S. B. (2012). Consequences of differences in cost-benefit methodology in railway infrastructure appraisal—A comparison between selected countries. Transport Policy, 22, 29-35. doi:10.1016/j.tranpol.2012.03.005Özgür, Ö. (2011). Performance analysis of rail transit investments in Turkey: İstanbul, Ankara, İzmir and Bursa. Transport Policy, 18(1), 147-155. doi:10.1016/j.tranpol.2010.07.004Özkır, V., & Demirel, T. (2012). A fuzzy assessment framework to select among transportation investment projects in Turkey. Expert Systems with Applications, 39(1), 74-80. doi:10.1016/j.eswa.2011.06.051Pardo-Bosch, F., & Aguado, A. (2014). Investment priorities for the management of hydraulic structures. Structure and Infrastructure Engineering, 11(10), 1338-1351. doi:10.1080/15732479.2014.964267Phillips, L. D., & Bana e Costa, C. A. (2007). Transparent prioritisation, budgeting and resource allocation with multi-criteria decision analysis and decision conferencing. 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    Total safety by design: Increased safety and operability of supply chain of inland terminals for containers with dangerous goods

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    [EN] In recent years, there has been a considerable increase in the international transport of containers with dangerous goods, increasing the risk of seaports and surrounding cities together with the introduction of inherent environmental and security disaster risks. Therefore, there is an increasing interest in seaports that are more socially inclusive, addressing the storage of containers of hazardous goods to safe inland terminals. An appropriate design of inland terminals for containers with dangerous goods (ITDGs) may contribute to the achievement of a sustainable development and the minimization of risks, avoiding disasters such as Tianjin. The objective of this study was the analysis of the criteria used for the design of safe, secure, cost efficient and greener ITDGs by applying the multicriteria decision theory AHP (analytic hierarchy process). Criteria regarding safety and security, environmental care, productivity and information and communication technologies (ICT) have been considered simultaneously into a total performance management system. (C) 2016 Elsevier Ltd. All rights reserved.Public funding entity: Generalitat Valenciana.Molero Prieto, GD.; Santarremigia Rosaleny, FE.; Aragonés-Beltrán, P.; Pastor-Ferrando, J. (2017). Total safety by design: Increased safety and operability of supply chain of inland terminals for containers with dangerous goods. Safety Science. 100(B):168-182. https://doi.org/10.1016/j.ssci.2016.10.007S168182100

    Effect of experimental conditions on free-living marine nematodes

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    Los nematodos han sido ampliamente utilizados para evaluar diferentes tipos de disturbios. El objetivo de este trabajo fue comparar la abundancia de la comunidad de nematodos marinos de vida libre en condiciones in situ y ex situ para evaluar el efecto de las condiciones experimentales en el laboratorio. Para ello, se colectaron muestras de sedimento en 3 sitios del golfo San Jorge (GSJ) y se las incubó en el laboratorio bajo condiciones controladas de luz, aire y temperatura, durante 45 días. Al finalizar este período, se analizaron cinco muestras del tratamiento ex situ y se colectaron otras cinco muestras in situ en los sitios estudiados. Luego se comparó la abundancia de nematodos y las características de los sedimentos entre ambos sets de muestras. Los resultados mostraron que existe un efecto de las condiciones de laboratorio sobre la fauna de nematodos y éste es más evidente en las muestras provenientes de sitios sin historia previa de contaminación, como es el caso de PG.Centro de Investigaciones Geológica

    Effect of experimental conditions on free-living marine nematodes

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    Los nematodos han sido ampliamente utilizados para evaluar diferentes tipos de disturbios. El objetivo de este trabajo fue comparar la abundancia de la comunidad de nematodos marinos de vida libre en condiciones in situ y ex situ para evaluar el efecto de las condiciones experimentales en el laboratorio. Para ello, se colectaron muestras de sedimento en 3 sitios del golfo San Jorge (GSJ) y se las incubó en el laboratorio bajo condiciones controladas de luz, aire y temperatura, durante 45 días. Al finalizar este período, se analizaron cinco muestras del tratamiento ex situ y se colectaron otras cinco muestras in situ en los sitios estudiados. Luego se comparó la abundancia de nematodos y las características de los sedimentos entre ambos sets de muestras. Los resultados mostraron que existe un efecto de las condiciones de laboratorio sobre la fauna de nematodos y éste es más evidente en las muestras provenientes de sitios sin historia previa de contaminación, como es el caso de PG.Centro de Investigaciones Geológica

    Magnetic order in a CuII-DyIII oxamato-based two-dimensional coordination polymer

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    We report the synthesis, crystal structure and magnetic characterization of a novel two-dimensional copper(II)-dysprosium(III) coordination polymer of formula [LiI(OH2)4]2[DyIIICuII2(Me2pma)4Cl(H2O)] . 4H2O (1) [Me2pma = N-2,6-dimethylphenyloxamate]. Compound 1 was obtained by using the mononuclear anionic complex, [CuII(Me2pma)2]2-, as a bis(bidentate) metalloligand toward solvated dysprosium(III) cations and shows a square [DyIIICuII2] layered structure of (44.62) net topology. Interestingly, the combination of two factors, the well-known efficiency of oxamato ligands to transmit strong magnetic couplings between neighboring atoms and such structural topology, is responsible for the observation of a ferromagnetic interaction between copper(II) and dysprosium(III) cations and a magnetic ordering (TC = 7.5 K), paving the way for the obtention of novel future examples of the still very scarce magnetically ordered lanthanide-based coordination polymers

    Effect of experimental conditions on free-living marine nematodes

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    Los nematodos han sido ampliamente utilizados para evaluar diferentes tipos de disturbios. El objetivo de este trabajo fue comparar la abundancia de la comunidad de nematodos marinos de vida libre en condiciones in situ y ex situ para evaluar el efecto de las condiciones experimentales en el laboratorio. Para ello, se colectaron muestras de sedimento en 3 sitios del golfo San Jorge (GSJ) y se las incubó en el laboratorio bajo condiciones controladas de luz, aire y temperatura, durante 45 días. Al finalizar este período, se analizaron cinco muestras del tratamiento ex situ y se colectaron otras cinco muestras in situ en los sitios estudiados. Luego se comparó la abundancia de nematodos y las características de los sedimentos entre ambos sets de muestras. Los resultados mostraron que existe un efecto de las condiciones de laboratorio sobre la fauna de nematodos y éste es más evidente en las muestras provenientes de sitios sin historia previa de contaminación, como es el caso de PG.Centro de Investigaciones Geológica

    Modelling the performance of port terminals using microsimulation

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    [EN] Globalization has caused an increase in cargo volumes in ports, which is starting to produce congestion in some of the main ports, delays in the whole supply chain, higher costs, retention in the vicinity of ports, and more pollution. All of these issues highlight the need to improve current container terminals by searching for enhanced management models. The terminal operating system (TOS) is the operational control system used in container terminals. An improvement of TOS with better functionalities, and their optimization, would increase the efficiency of the terminal. In a previous study, the authors identified and weighted TOS functionalities using the analytic hierarchy process (AHP) method. The aim of this paper is to analyse by simulation how the improvement of the most influential TOS functionalities affects the operational and the environmental performance of a container terminal. Two new TOSs (TOS 2 and TOS 3) were compared with the TOS (TOS 1) currently used at Intersagunto terminal (Spain) by microsimulation using FlexTerm. Results show that modifications to the TOS can improve certain operational aspects, such as the number of containers handled, the occupation of the storage yard, and the dwell times; however, there were not significant improvements in energy consumption and carbon footprint. Further developments should address this issue by modifying other TOS functionalities in order to obtain both operational and environmental improvements at the terminal. This paper is addressed to managers of container terminals, TOS designers, researchers in the field of ports and terminals, and port authorities.This study was co-funded by Instituto Valenciano de Competitividad (IVACE) and the European Regional Development Fund (ERDF) under project reference IMIDCA/2017/32.Hervás-Peralta, M.; Rozic, T.; Poveda-Reyes, S.; Santarremigia, FE.; Pastor-Ferrando, J.; Molero, GD. (2020). Modelling the performance of port terminals using microsimulation. European Transport / Trasporti Europei. (76):1-11. http://hdl.handle.net/10251/165840S1117

    Ecofriendly Perovskites with Giant Self-Defocusing Optical Response

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    [EN] The full optical control of light using sustainable green technologies is one of the incipient challenges of the Photonics community. There are, however, few optical materials able to provide a significant nonlinear refractive index change under small enough intensities (< 1 GW cm(-2)), and, more importantly, allowing the external control of the magnitude and sign of their nonlinear response. This manuscript demonstrates that Cs2SnI6 lead-free nanocrystals (NCs) present an extraordinary self-defocusing response not yet observed up to now in any material. Despite its complex structural form, these NCs are fully characterized here, both experimentally and theoretically, revealing a giant negative refractive change Delta n = -0.05 under proper illumination conditions. The nonlinear response is tuned with the intensity, concentration of NCs in the solvent, and propagation distance leading to a crossover where the media transforms to self-focusing with Delta n = +0.002. These results can provide fascinating opportunities in sensing and light-matter interactions for a future ecofriendly photonic technology.This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement no. 862656 (project DROP-IT) and by the Spanish MICINN through project no. PID2020-120484RB-I00 and by Generalitat Valenciana PROMETEO/2021/082.Suárez, I.; Martinez-Pastor, JP.; Oszajca, MF.; Lüchinger, NA.; Graves, B.; Agouram, S.; Milián Enrique, C.... (2022). Ecofriendly Perovskites with Giant Self-Defocusing Optical Response. Advanced Optical Materials. https://doi.org/10.1002/adom.20220212
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