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El model de resolució de problemes científics definits per equacions diferencials parcials PGD és molt utilitzat en el sector d'investigació. A LaCàN fa anys que estudien i desenvolupant un model que anomenen encapsulated PGD que apunta a extendre les capacitats de l'algorisme. Per a això, proposen un seguit de procediments per a realitzar càlculs entre tensors separats, els objectes principals amb els quals la PGD treballa. L'objectiu del projecte és portar aquests anys d'estudi a la realitat en format de codi obert. Per a funcionar correctament, tots els algorismes han de ser el màxim d'eficients possibles, ja que estem parlant de matrius de magnituds de milions de files i columnes. A més, es proposa l'ús de tècniques de paral·lelisme per tal de donar oportunitat d'executar problemes de grans dimensions en el menor temps possible., The model for solving scientific problems defined by partial differential equations PGD is widely used in the research sector. At LaCàN they have been studying and developing a different approach called encapsulated PGD that aims to extend the capabilities of the algorithm. For this, they propose a series of procedures to perform calculations between separated tensors, the main objects which the PGD works with. The goal for the project is to bring these years of study to reality in open source format. To properly work, all algorithms must be as efficient as possible, since we are talking about matrices with millions of rows and columns. In addition, the use of parallelism techniques is proposed in order to give the opportunity to execute large problems in the shortest possible time.

© 2022 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0, The pervasive use of mobile devices has brought a valuable new source of data. The work presented here has a twofold objective: firstly, to demonstrate the capability of mobile phone records to feed traditional trip-based demand models and, secondly, to assert the possibilities of using developed models to estimate the effects of new urbanistic development scenarios. Detailed trip data for the metropolitan area of Barcelona are reconstructed from mobile phone records. This information is then employed as input for building a set of demand trip-based models and to apply these daily-based models to the appraisal of new development scenarios in a VISUM model of the city. The model calibration and validation process proves the quality of the models obtained. Our results show the way in which the generated trips are distributed into the study area and modal share is modified in the considered scenarios., This research was funded by TRA2016-76914-C3-1-P Spanish R+D Programs, Secretaria d’Universitats-i-RecercaGeneralitat de Catalunya- 2017-SGR- 1749. The authors are grateful for the support given by the Autoritat del Transport Metropolità (ATM) providing us with their model (Ll. Alegre, F. Calvet, and X. Sanyer). We are also grateful to Dra. L. Pagés (CARNET-UPC), J. Llinàs and A. Ortiz (Barcelona Regional) for their support., Peer Reviewed, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles, Objectius de Desenvolupament Sostenible::10 - Reducció de les Desigualtats, Postprint (published version)

Una tasca que pren molt de temps, no sempre és acurada i no s'aprofita al màxim és l'etiquetat de les publicacions dels investigadors. En aquest projecte es desenvoluparà procés que ho automatitzi, i a més a més generi un mapa d'àrees de coneixement de la UPC. Es faran tests amb diferentes eines de NLP, per garantir els millors resultats possibles. Els mapes generats seran molt útils per saber temes emergents i facilitar les preses de decisions sobre on invertir i encaminar futures investigacions., A task that requires a lot of time, that is not always accurate and that is not exploited to its maximum is the labelling of the investigator's publications. In this project, a process that will automatize it will be developed, and moreover, it will generate a map of knowledge areas within the UPC. Different tests will be conducted using NLP tools, in order to ensure the best possible results. The maps generated will be highly useful to show cutting-edge subjects and to facilitate the decision making on where to invest and direct future investigations.

Wear in train and rail components in the Barcelona subway system includes brake pads, catenary wires, wheels, railways, and motor brushes. These components were characterised to evaluate their contribution to ambient particulate matter (PM) levels in two platforms (conventional F-L3 and new S-L9). The observed chemical compositions of these components were used to interpret the mineralogical, chemical, and leachability patterns of subway platform particulate matter (PM). The use of sulphides such as molybdenite (MoS 2 ), pyrite (FeS 2 ), stibnite Sb 2 S 3 ) rich in toxic elements such as in Cu, Ni, As, Hg, Cd, and Pb and abrasives such barite (BaSO 4 ) and zinzite (ZnO) in the brake pad composition, the composition of the catenary rich in Cu (98% metallic-Cu) with traces of Hg and that of the wheel/rail (98% metallic-Fe) with traces of As results in the production of fine PM particles of As, Hg, Cu, and Sb in ambient air PM in platform as a consequence of the abrasion/friction and sparking processes. The temperature reached in the aforementioned processes give rise to fine condensed and water-soluble As species (most likely As 2 O 3 and As 2 O 5 ). Moreover, the stibnite (Sb 2 S 3 ) Hg-rich lateral brake pads used in L9 also contribute to fine and relatively soluble Sb and Hg oxides. Sulphide-rich brake pads significantly increase and change the occurrence mode of the Zn, Cu, Mn, Cr, Pb, and Ni present in PM by oxidation of brake-bearing metal sulphide to relatively water-soluble sulphate and oxide species. These changes in the mode of occurrence and speciation of elements in the PM of subway platforms points to the need for in-depth PM speciation studies, as well as the need for substituting conventional friction materials with low-metal materials—such as graphite pantographs/catenaries and rubber wheels and low toxic sulphides in brake pads—to reduce exposure to metals during subway commuting. © 2019

Dins el camp del Data Science, Learning Analytics tracta d'entendre i optimitzar l'aprenentatge i l'entorn on aquest ocorre a partir de la recol·lecció i anàlisi de dades massives. En aquest context es desenvolupa el projecte Learning Analytics for Secondary (LA4S) de l'inLab FIB, que analitza les traces digitals generades per Learning Management Systems (LMS), creant indicadors sobre la motivació. L'objectiu principal d'aquest Treball Final de Grau és modelar les dades d'un LMS sobre una ontologia, calcular un conjunt dels indicadors sobre la motivació del projecte LA4S i, amb aquests indicadors, tractar de desenvolupar un model de predicció per a detectar quins alumnes estan en risc de fracas escolar. En aquest treball s'ha construint part de l'ontologia i els indicadors de motivació, s'han analitzat aquests últims, i s'ha intentat construir models de predicció amb el conjunt de dades disponibles., In the field of Data Science, Learning Analytics aims to understand and optimize learning and the environment where it occurs with the recollection and analysis of massive data. In this context the project Learning Analytics for Secondary (LA4S) of the inLab FIB is developed, analyzing digital traces generated by Learning Management Systems (LMS), and creating motivation indicators. The main goal of this Bachelor's Degree Final Project is modeling the data of a LMS using an ontology, calculate a set of the motivation indicators of the LA4S project and developing a prediction model with them to identify which students are at risk of dropout. In this project a fraction of the ontology and the indicators are generated, analyzing the indicators and trying to develop some prediction models with the available data.

FIB Alumni és l'associació d'antics estudiants de la Facultat d'Informàtica de Barcelona. Aquest projecte consisteix a construir un portal web i una app mòbil per a Android, amb els objectius de dinamitzar la seva activitat, així com proveir a la Junta d'una eina de gestió dels seus afers., FIB Alumni is the former students association of the Computer Science School of Barcelona. This project consists in building a web portal and a mobile app for Android, with the objectives of dynamising its activity, as well as providing the Board with a tool for managing their affairs.

School is an essential context that contributes to children's communicative competence. Decision Support Systems (DSS) are tools that can help teachers to assess their own practice and to make decisions to improve it (Gregg, 2009). Our aim is the construction, implementation and validation of a digital Decision Support System (EVALOE-DSS), conceived as a teacher empowerment tool for self-assessment and decision making about their teaching practice concerning students' oral skills. Participants are 4 teachers and their groups of students of 4 diverse schools. The research procedure includes: 1) design and development of a DSS for different type of schools; 2) researcher assessment of one classroom observation using EVALOE-DSS; 3) weekly teacher self-assessment of classroom observation and decision making using EVALOE-DSS; 4) analysis of self-assessments, decision making and changes in teaching practices; 5) teacher-researcher assessment of the helpfulness of DSS and introduction of changes. EVALOE-DSS is a multimedia tool consisting of 30 items that assess 5 dimensions: teaching management, instructional design, communicative functions and teacher strategies, students' communicative functions, and students' management. It includes, also, a brief description of each item and a variety of resources to help teachers to make decisions and introduce the actions in their teaching practice., Peer Reviewed, Postprint (author's final draft)

Millions of people use rail subway public transport around the world, despite the relatively high particulate matter (PM) concentrations in these underground environments, requiring the identification and quantification of the aerosol source contributions to improve the air quality. An extensive aerosol monitoring campaign was carried out in eleven subway stations in the Barcelona metro system, belonging to seven subway lines. PM2.5 samples were collected during the metro operating hours and chemically analysed to determine major and trace elements, inorganic ions, and total carbon. The chemical compositions of subway components such as brake pads, rail tracks and pantographs were also determined. The mean PM2.5 concentrations varied widely among stations, ranging from 26 µg m−3 to 86 µg m−3. Subway PM2.5 was mainly constituted by Fe2O3 (30–66%), followed by carbonaceous matter (18–37%) for the old stations, while for new stations equipped with Platform Screen Doors (PSD) these percentages go down to 21–44% and 15–30%, respectively. Both the absolute concentrations and the relative abundance of key species differed for each subway station, although with common patterns within a given subway line. This is a result of the different emission chemical profiles in different subway lines (using diverse types of brakes and/or pantographs). The co-emission of different sources poses a problem for their separation by receptor models. Nevertheless, receptor modelling (Positive Matrix Factorization) was applied resulting in ten sources, five of them subway-specific: RailWheel, RailWheel+Brake, Brake_A, Brake_B, Pb. The sum of their contributions accounted for 43–91% of bulk PM2.5 for the old stations and 21–52% for the stations with PSD. The decrease of the activity during the weekends resulted in a decrease (up to 56%) in the subway-specific sources contribution to the –already lower– bulk PM2.5 concentrations compared to weekdays. The health-related elements are mainly appor

The present work assesses indoor air quality in stations of the Barcelona subway system. PM2.5 concentrations on the platforms of 4 subway stations were measured during two different seasons and the chemical composition was determined. A Positive Matrix Factorization analysis was performed to identify and quantify the contributions of major PM2.5 sources in the subway stations. Mean PM2.5 concentrations varied according to the stations design and seasonal periods. PM2.5 was composed of haematite, carbonaceous aerosol, crustal matter, secondary inorganic compounds, trace elements, insoluble sulphate and halite. Organic compounds such as PAHs, nicotine, levoglucosan and aromatic musk compounds were also identified. Subway PM2.5 source comprised emissions from rails, wheels, catenaries, brake pads and pantographs. The subway source showed different chemical profiles for each station, but was always dominated by Fe. Control actions on the source are important for the achievement of better air quality in the subway environment. © 2015 The Authors.

Most particles breathed on rail subway platforms are highly ferruginous (FePM) and extremely small (nanometric to a few microns in size). High magnification observations of particle texture and chemistry on airborne PM10 samples collected from the Barcelona Metro, combined with published experimental work on particle generation by frictional sliding, allow us to propose a general model to explain the origin of most subway FePM. Particle generation occurs by mechanical wear at the brake-wheel and wheel-rail interfaces, where magnetic metallic flakes and splinters are released and undergo progressive atmospheric oxidation from metallic iron to magnetite and maghemite. Flakes of magnetite typically comprise mottled mosaics of octahedral nanocrystals (10-20nm) that become pseudomorphed by maghemite. Continued oxidation results in extensive alteration of the magnetic nanostructure to more rounded aggregates of non-magnetic hematite nanocrystals, with magnetic precursors (including iron metal) still preserved in some particle cores. Particles derived from steel wheel and rails contain a characteristic trace element chemistry, typically with Mn/Fe=0.01. Flakes released from brakes are chemically very distinctive, depending on the pad composition, being always carbonaceous, commonly barium-rich, and texturally inhomogeneous, with trace elements present in nanominerals incorporated within the crystalline structure. In the studied subway lines of Barcelona at least there appears to be only a minimal aerosol contribution from high temperature processes such as sparking. To date there is no strong evidence that these chemically and texturally complex inhalable metallic materials are any more or less toxic than street-level urban particles, and as with outdoor air, the priority in subway air quality should be to reduce high mass concentrations of aerosol present in some stations. © 2014.

Access to detailed comparisons in air quality variations encountered when commuting through a city offers the urban traveller more informed choice on how to minimise personal exposure to inhalable pollutants. In this study we report on an experiment designed to compare atmospheric contaminants inhaled during bus, subway train, tram and walking journeys through the city of Barcelona. Average number concentrations of particles 10-300 nm in size, N, are lowest in the commute using subway trains (N<2.5 ×104part.cm-3), higher during tram travel and suburban walking (2.5 ×104cm-35.0×104cm-3), with extreme transient peaks at busy traffic crossings commonly exceeding 1.0×105cm-3 and accompanied by peaks in Black Carbon and CO. Subway particles are coarser (mode 90nm) than in buses, trams or outdoors (<70nm), and concentrations of fine particulate matter (PM2.5) and Black Carbon are lower in the tram when compared to both bus and subway. CO2 levels in public transport reflect passenger numbers, more than tripling from outdoor levels to >1200ppm in crowded buses and trains. There are also striking differences in inhalable particle chemistry depending on the route chosen, ranging from aluminosiliceous at roadsides and near pavement works, ferruginous with enhanced Mn, Co, Zn, Sr and Ba in the subway environment, and higher levels of Sb and Cu inside the bus. We graphically display such chemical variations using a ternary diagram to emphasise how "air quality" in the city involves a consideration of both physical and chemical parameters, and is not simply a question of measuring particle number or mass. © 2015 The Authors.