Selection of rail improvement projects using the Analytic Network Process

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

[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

[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). Decision Support Framework for Infrastructure Maintenance Investment Decision Making. Journal of Management in Engineering, 32(1), 04015030. doi:10.1061/(asce)me.1943-5479.0000372Arunraj, N. S., & Maiti, J. (2010). Risk-based maintenance policy selection using AHP and goal programming. Safety Science, 48(2), 238-247. doi:10.1016/j.ssci.2009.09.005Asensio, J., & Matas, A. (2008). Commuters’ valuation of travel time variability. Transportation Research Part E: Logistics and Transportation Review, 44(6), 1074-1085. doi:10.1016/j.tre.2007.12.002Bana e Costa, C. A., & Oliveira, R. C. (2002). Assigning priorities for maintenance, repair and refurbishment in managing a municipal housing stock. European Journal of Operational Research, 138(2), 380-391. doi:10.1016/s0377-2217(01)00253-3Bana e Costa, C. A., & Vansnick, J.-C. (2008). A critical analysis of the eigenvalue method used to derive priorities in AHP. 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A multiple criteria approach for the evaluation of the rail transit networks in Istanbul. Transportation, 31(2), 203-228. doi:10.1023/b:port.0000016572.41816.d2Goverde, R. M. P. (2010). A delay propagation algorithm for large-scale railway traffic networks. Transportation Research Part C: Emerging Technologies, 18(3), 269-287. doi:10.1016/j.trc.2010.01.002Grimes, G. A., & Barkan, C. P. L. (2006). Cost-Effectiveness of Railway Infrastructure Renewal Maintenance. Journal of Transportation Engineering, 132(8), 601-608. doi:10.1061/(asce)0733-947x(2006)132:8(601)Harker, P. T., & Vargas, L. G. (1990). Reply to «Remarks on the Analytic Hierarchy Process» by J. S. Dyer. Management Science, 36(3), 269-273. doi:10.1287/mnsc.36.3.269Huisman, T., & Boucherie, R. J. (2001). Running times on railway sections with heterogeneous train traffic. Transportation Research Part B: Methodological, 35(3), 271-292. doi:10.1016/s0191-2615(99)00051-xHwang, C.-L., & Yoon, K. (1981). 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

[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

Modelling the performance of port terminals using microsimulation

[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

Optical amplification in hollow-core negative-curvature fibers doped with perovskite CsPbBr3 nanocrystals

We report a hollow-core negative-curvature fiber (HC-NCF) optical signal amplifier fabricated by the filling of the air microchannels of the fiber with all-inorganic CsPbBr3 perovskite nanocrystals (PNCs). The optimum fabrication conditions were found to enhance the optical gain, up to +3 dB in the best device. Experimental results were approximately reproduced by a gain assisted mechanism based on the nonlinear optical properties of the PNCs, indicating that signal regeneration can be achieved under low pump powers, much below the threshold of stimulated emission. The results can pave the road for new functionalities of the HC-NCF with PNCs, such as optical amplification, nonlinear frequency conversion and gas sensors

Propagation length enhancement of surface plasmon polaritons in gold nano-/microwaveguides by the interference with photonic modes in the surrounding active dielectrics

In this work, the unique optical properties of surface plasmon polaritons (SPPs), i.e. subwavelength confinement or strong electric field concentration, are exploited to demonstrate the propagation of light signal at 600 nm along distances in the range from 17 to 150 μm for Au nanostripes 500 nm down to 100 nm wide (30 nm of height), respectively, both theoretically and experimentally. A low power laser is coupled into an optical fiber tip that is used to locally excite the photoluminescence of colloidal quantum dots (QDs) dispersed in their surroundings. Emitted light from these QDs is generating the SPPs that propagate along the metal waveguides. Then, the above-referred propagation lengths were directly extracted from this novel experimental technique by studying the intensity of light decoupled at the output edge of the waveguide. Furthermore, an enhancement of the propagation length up to 0.4 mm is measured for the 500-nm-wide metal nanostripe, for which this effect is maximum. For this purpose, a simultaneous excitation of the same QDs dispersed in poly(methyl methacrylate) waveguides integrated with the metal nanostructures is performed by end-fire coupling an excitation laser energy as low as 1 KW/cm2. The proposed mechanism to explain such enhancement is a non-linear interference effect between dielectric and plasmonic (super)modes propagating in the metal-dielectric structure, which can be apparently seen as an effective amplification or compensation effect of the gain material (QDs) over the SPPs, as previously reported in literature. The proposed system and the method to create propagating SPPs in metal waveguides can be of interest for the application field of sensors and optical communications at visible wavelengths, among other applications, using plasmonic interconnects to reduce the dimensions of photonic chips

An AHP (Analytic Hierarchy Process)/ANP (Analytic Network Process)-based multi- criteria decision approach for the selection of solar-thermal power plant investment projects

In this paper the AHP (Analytic Hierarchy Process) and the ANP (Analytic Network Process) are applied to help the managing board of an important Spanish solar power investment company to decide whether to invest in a particular solar-thermal power plant project and, if so, to determine the order of priority of the projects in the company's portfolio. Project management goes through a long process, from obtaining the required construction permits and authorizations, negotiating with different stakeholders, complying with complex legal regulations, to solving the technical problems associated with plant construction and distribution of the energy generated. The whole process involves high engineering costs. The decision approach proposed in this paper consists of three phases. In the first two phases, the managing board must decide whether to accept or reject a project according to a set of criteria previously identified by the technical team. The third phase consists of establishing a priority order among the projects that have proven to be economically profitable based on project risk levels and execution time delays. This work analyzes the criteria that should be taken into account to accept or reject proposals for investment, as well as the risks used to prioritize some projects over others.The translation of this paper has been funded by the Universitat Politecnica de Valencia.Aragonés Beltrán, P.; Chaparro González, FV.; Pastor Ferrando, JP.; 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.2013.12.016S2222386

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

Combinations of single-top-quark production cross-section measurements and vertical bar f(LV)V(tb)vertical bar determinations at root s=7 and 8 TeV with the ATLAS and CMS experiments

This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb(-1) at = 7 TeV and 12.2 to 20.3 fb(-1) at = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 +/- 5.7 pb and 87.7 +/- 5.8 pb at = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 +/- 4.1 pb and 23.1 +/- 3.6 pb at = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 +/- 1.4 pb at = 8 TeV. The square of the magnitude of the CKM matrix element V-tb multiplied by a form factor f(LV) is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |V-td|, |V-ts| << |V-tb|. All the |f(LV)V(tb)|(2) determinations, extracted from individual ratios at = 7 and 8 TeV, are combined, resulting in |f(LV)V(tb)| = 1.02 +/- 0.04 (meas.) +/- 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions.Peer reviewe