Vibration-Based Machine Learning Models for Condition Monitoring of Railroad Rolling Stock

One of the primary causes of rail rolling stock derailments is attributed to bearing and wheel axle failures. The health of train bearings is primarily monitored at target locations through wayside detection systems. This practice is susceptible to bearing failure and potential derailments at points in between these wayside systems. To remedy this, the University Transportation Center for Railway Safety (UTCRS) has developed a wireless onboard monitoring system that can continuously monitor the vibration response, which directly correlates to the health of bearings. This data is used to train regression-based machine learning algorithms and long-term prediction neural networks to predict bearing health. The models are intended to work in tandem with the onboard monitoring sensors as a means of two-way practical validation. The models tested were the Gradient Boosting Machine architecture for scheduled predictions and the Informer neural network architecture for long-term predictions of ongoing routes. The dataset for these models comes from the expansive laboratory record data available at the UTCRS. Ultimately, these machine learning algorithms will enhance freight railcars safety and save rail companies money by allowing for predictive maintenance practices

An exploratory social network analysis of academic research networks

For several decades, academics around the world have been collaborating with the view to support the development of their research domain. Having said that, the majority of scientific and technological policies try to encourage the creation of strong inter-related research groups in order to improve the efficiency of research outcomes and subsequently research funding allocation. In this paper, we attempt to highlight and thus, to demonstrate how these collaborative networks are developing in practice. To achieve this, we have developed an automated tool for extracting data about joint article publications and analyzing them from the perspective of social network analysis. In this case study, we have limited data from works published in 2010 by England academic and research institutions. The outcomes of this work can help policy makers in realising the current status of research collaborative networks in England

Lewis acidic metal complexes with polydentate ligands for the preparation of biorenewable polymers

Due to the ever increasing necessity to reduce our dependence on fossil fuels as feedstocks for polymeric materials, the work presented herein describes the investigation of new metal complexes as initiators for the formation of polyesters and polycarbonates from renewable monomers. These polymers are regarded as biodegradable and have the properties required to replace traditional plastics in applications such as food packaging, electronic devices, and medical biomaterials. Chapter one introduces previous literature relevant to the research on which this study focuses; ligands based on alkoxides, phosphine oxides and N-heterocyclic carbenes with alkoxide or amino pendant groups, as well as the metal complexes in which they are used. Current methods of polymerisation and copolymerisation and the initiators utilised are also examined. Chapter two contains the design and synthesis of [M(LR n)]m metal complexes where LR is [(R)2P(O)CH2CH(tBu)O]– and R is Ph or tBu. Divalent metal centres such as CoII and ZnII have been used for the formation of the studied compounds. Studies on their reactivity as initiators for polymerisations are also described. Chapter three presents the utilisation of di- and tridentate ligands, with one or two NHC species respectively, for the synthesis of [Mx(LY n)], where M is CuI, ZnII or TiIII and LY is an alkoxy-tethered NHC species or a ‘CNC’ tridentate ligands with an amino derivative as bridge. Their reactivity and ability to act as initiators for polymerisation reactions was also examined. Chapter four comprises overall conclusions of this work and the impact of these investigations. Chapter five outlines the experimental details and data for the compounds presented

Internal to external platform sedimentation with development of mud-mounds during Viséan from the central area of the Sierra de la Estrella (Carboniferous, Córdoba, Spain)

[ES] En la Sierra de la Estrella (Área del Guadiato, Córdoba) se localiza una sucesión del Viseense superior, principalmente carbonatada, con desarrollo de montículos tipo mud-mound. En esta zona predominan calizas bioclásticas, brechoideas y bioconstruidas, aunque también se localizan niveles de areniscas y conglomerados. Se han identificado un total de 7 litofacies que agrupan a su vez a 9 microfacies tipo: 1.–Mudstonewackestone con cavidades estromatactoideas y fábricas fenestrales, 2.–Wackestonepackstone con algas y bioclastos, 3.1.–Packstone de pseudopeloides, 3.2.–Packstone con algas, pseudopeloides y litoclastos, 4.1.–Packstone de briozoos y crinoideos, 4.2.–Packstone con algas y espículas, 5.–Packstone-rudstone de litoclastos, 6.–Grainstone de cortoides y litoclastos, 7.–Arenitas híbridas. El ambiente de sedimentación se interpreta como una zona de transición entre rampa interna y externa carbonática con influencia de terrígenos y desarrollo de montículos microbianos.[EN] Late Viséan calcareous rocks containing buildups occur in the Sierra de la Estrella, Guadiato Valley. Bioclastic, breccioid and biohermal limestones as well as sandstones and conglomerates occur. Lithofacies analysis allow to identify 7 types, with 9 characteristic microfacies: 1.–Micropeloidal mudstone-wackestone with stromatactoid cavities and fenestral fabrics, 2.–Algal-bioclastic wackestone-packstone, 3.1.–Pseudopeloidal packstone, 3.2.–Packstone with algae, pseudopeloids and lithoclast, 4.1.–Bryozoal-crinoidal packstone, 4.2.–Packstone with algae and sponge spiculae, 5.–Packstone-rudstone with lithoclasts, 6.–Cortoid-lithoclasts grainstone, 7.–Hybrid sandstones. Sediments are attributed to a inner to outer carbonate ramp with sporadic terrigenous influence. Some microbial mounds developed in such environment.Este trabajo se enmarca en el proyecto PB 96-0842 de la DGICYT.Peer reviewe

The evolution of enzyme function in the isomerases.

The advent of computational approaches to measure functional similarity between enzymes adds a new dimension to existing evolutionary studies based on sequence and structure. This paper reviews research efforts aiming to understand the evolution of enzyme function in superfamilies, presenting a novel strategy to provide an overview of the evolution of enzymes belonging to an individual EC class, using the isomerases as an exemplar

Identification of Influencers in eWord-of-Mouth communities using their Online Participation Features

[EN] The identification of influencers in any type of online social network is of paramount importance, as they can significantly affect consumers’ purchasing decisions. This paper proposes the utilization of a self-designed web scraper to extract meaningful information for the identification of influencers and the analysis of how this new set of variables can be used to predict them. The experimental results from the Ciao UK website will be used to illustrate the proposed approach and to provide new insights in the identification of influencers. Obtained results show the importance of the trust network, but considering the intensity and the quality of both trustors and trustees.Olmedilla, M.; Arenas-Márquez, FJ.; Martinez-Torres, MR.; Toral, SL. (2016). Identification of Influencers in eWord-of-Mouth communities using their Online Participation Features. En CARMA 2016: 1st International Conference on Advanced Research Methods in Analytics. Editorial Universitat Politècnica de València. 38-45. https://doi.org/10.4995/CARMA2016.2016.3642OCS384

Atmospheric deposition fluxes of aluminium, iron and trace metals in a coastal station on the NW-Alboran Sea, (W-Mediterranean)

El estudio se ha realizado en el marco del Proyecto del Plan Nacional con ref. CTM12-37598-C02The atmospheric deposition over the whole Mediterranean is poorly constrained and hinders a clear assessment of the extent to which atmospheric elements of various anthropogenic and natural origins affect its biogeochemistry. Available data show poor spatial representation, as most of the deposition data refer to the northwestern zone. The Alboran Sea, in particular, is a very interesting case study as regards the atmospheric input because the atmospheric chemistry is dominated by antagonistic influences of natural (mainly from the Sahara) and human activity due to the relative proximity of land-based sources and densely populated shores. The biogeochemical impact of desert dust also remains a matter of discussion regarding its contribution for different major and minor elements to terrestrial and marine systems and especially its potential fertilizing role by supplying micronutrients as iron. Atmospheric fluxes of various trace metals were measured in order to evaluate the presence of these elements in their differently bio-available forms, contents in the soluble and non-soluble fractions were determined. Sampling presented for this study was performed in Malaga (southeast of Spain, 36° 43′ 40″ N; 4° 28′ 8″ W) in an open bulk deposition collector placed 10 m above the ground. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model was used to calculate the backward trajectories of air masses reaching the study region.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Detailed damage mechanisms assessment in composite materials by means of X-ray tomography

This research focused on the evaluation of damage formation on ±45º carbon fiber laminates subjected to tensile tests. The damage was evaluated by means of X-ray tomography. A high density of cracks developed during the plateau of the stress-strain curve and were qualitatively analyzed, showing that the inner plies eventually developed a higher crack concentration than the outer plies. Delamination started to occur in the outermost ply interface when the slope after the plateau of the stress-strain curve began to increase