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A Hydrogen-Centric Approach in Catalonia: Opportunities and Challenges
No full textAs Catalonia embarks on its journey towards decarbonization, hydrogen emerges as a pivotal component of its clean energy strategy. This abstract presents a forecast of hydrogen utilization in Catalonia, shedding light on the opportunities and challenges inherent in its widespread adoption.
Hydrogen holds immense promise as a versatile energy carrier capable of decarbonizing various sectors, including transportation, industry, and residential heating. In Catalonia, the forecasted utilization of hydrogen reflects a strategic shift towards sustainable practices, driven by ambitious climate targets and technological advancements.
In the transportation sector, hydrogen fuel cell vehicles (FCVs) are poised to play a prominent role, offering zero-emission mobility without compromising range or refuelling convenience. Nowadays, TMB (Transports Municipals de Barcelona) has increased significantly the hydrogen buses fleet and some industrial examples are being developed, but not relative only to heavy transport also in intra logistic areas.
In the industrial sector, hydrogen emerges as a key enabler of decarbonization, particularly in energy-intensive industries such as chemicals and construction. The forecast highlights the potential for green hydrogen to replace fossil fuels in industrial processes, leading to significant reductions in carbon emissions and enhancing Catalonia's industrial competitiveness on the global stage and in Tarragona area.
Moreover, the forecast examines the integration of hydrogen into the residential sector, where it can serve as a clean alternative for heating and power generation. By leveraging renewable sources for hydrogen production and investing in decentralized hydrogen infrastructure, Catalonia aims to provide sustainable energy solutions to residential consumers, fostering energy independence and resilience.
However, the forecast also underscores several challenges that must be addressed to realize the full potential of hydrogen utilization in Catalonia. These include the need for robust regulatory frameworks, investment incentives, and public awareness campaigns to overcome technological barriers and market uncertainties.
In conclusion, the forecast of hydrogen utilization in Catalonia paints a compelling picture of a future characterized by sustainable energy practices, economic growth, and environmental stewardship. By seizing the opportunities presented by hydrogen technologies and addressing the associated challenges proactively, Catalonia can chart a course towards a decarbonized future that serves as a model for regions around the globe.
 
The flexibility imperative: tapping demand-side flexibility (DSF) in future decarbonised energy systems
No full textTransició energètica: Elements per a millorar-ne la governança
No full textProposta de Comunicació per a l’eix 1
Partint de la premissa d’un final amb energia 100% renovable i de l’imperatiu ètic de la lluita per la igualtat, la transició energètica es presenta amb una complexitat notable tant per la seva condició de ser mundial com pel fet de necessitar una aproximació multidisciplinària. Aquest és un punt de partida, que assumim, tal com queda plasmat en el llibre que serveix de base per aquesta comunicació: Transició energètica: Què és urgent? Què és important? d’un dels autors, Francesc Reventós Puigjaner, publicat per la Universitat Politècnica de Catalunya.
Com a problema mundial, la controvèrsia és abordada avui pels estats com un tema més de la cooperació internacional i molts són els que no estan disposats a cedir en les seves aspiracions de desenvolupament en les accions que es prenguin. Aquest problema és especialment rellevant tant en països emergents com en països del Sud global. Com a problema multidisciplinari estem davant d’una gestió complexa, tant a l’hora d’entendre els continguts de les especialitats científiques involucrades, com a la de cercar consens entre les parts.
Els resultats d’aquestes circumstàncies són un avenç lent i un dubte sobre el compliment dels objectius traçats. Tot i apreciant els acords i propostes de les successives conferències COP, el consens no arriba i la incertesa no sembla tractada adequadament.
Per bé que són molts els temes afectats d’aquesta problemàtica, la comunicació se centra a dos d’ells, la sobrietat o sostenibilitat i el paper de les centrals nuclears a la transició. Tots dos són tractats amb detall al text de referència, seran resumits convenientment i poden evolucionar en la direcció de produir millores notables en el progrés de la transició. Inevitablement sorgeix la pregunta sobre la suficiència de l’actual governança i ens sumem a la preocupació que també es reflecteix als documents preparatoris de la Cimera del Futur de les NU del proper setembre.
En un eventual reforçament de la governança, els autors consideren indispensable la necessitat de comptar amb un major protagonisme de la comunitat científica per avançar en la creació de consens. Basant-nos amb l’experiència d’haver tractat els dos grans temes en entorns científics, pensem que la utilització assenyada i accentuada d’aquests col·lectius ha de permetre una clara millora en l’establiment del consens necessari. L’IPCC (Intergovernamental Panel for Climate Change) és un bon exemple a seguir. Com a òrgan científic de la COP té el debat científic com a eina crucial per a avançar. Seguir aquest exemple a altres nivells ens portarà a un millor enteniment del problema i a una capacitat palesa en congeniar el mitjà i el llarg termini, establir plans B quan convingui o d’establir acords i consens. La indispensable entrada en escena d’ideòlegs, governs i empreses tindria lloc, de forma més justa i eficaç, un cop assegurat aquest coneixement multidisciplinari i científic previ
Aplicació de la Metodologia Random Forest per a la Detecció del Maquillatge Comptable: Un Estudi Empíric
No full textEix 10: La contribució dels professionals de l’economia
Justificació del seu interès
La incidència del frau i maquillatge comptable en els estats financers és un tema d'alta rellevància tant en l'àmbit acadèmic com en el professional, donant lloc a significatives pèrdues econòmiques i afectant la credibilitat de les empreses. La metodologia Random Forest ha demostrat ser una eina potent en la identificació de patrons de maquillatge comptable, oferint una nova perspectiva en la detecció de fraus.
Objectius
1. Identificar els senyals d'alerta més efectius per a la detecció de maquillatge comptable.
2. Validar l'eficàcia de la metodologia Random Forest en l'anàlisi de dades comptables.
3. Contribuir a la millora de la transparència i la integritat financera en el sector empresarial.
Resultats que s'espera obtenir
S'espera identificar de manera fiable els senyals més importants a l´hora d'alerta de maquillatge comptable. conjunt de 55 variables analitzades.
Conclusions que s'espera assolir
Amb aquesta recerca es preveu demostrar per una banda, l'aplicabilitat i l'eficiència del Random Forest en la detecció de maquillatge comptable, oferint eines robustes per a auditors i reguladors. Per altra banda, identificar quins són els senyals que tenen més poder predictiu per a la identificació de les empreses que cometen engany comptable dintre d´un conjunt de 55 variables quantitatives i qualitatives.
Es tracta d’una proposta que pot ser d’utilitat per a auditors, analistes i organismes supervisors i qualsevol persona interessada en la informació econòmica financera i no financera proporcionada per les empreses, afavorint un entorn empresarial més ètic i transparent.
 
A Digital Twin for Assessing the Remaining Useful Life of Offshore Wind Turbine Structures
Get PDFThis paper delves into the application of digital twin monitoring techniques for enhancing offshore floating wind turbine performance, with a detailed case study that uses open-source digital twin software. We explore the practical implementation of digital twins and their efficacy in optimizing operations and predictive maintenance, focusing on controlling the real-time structural state of composite wind turbine structures and forecasting the remaining useful life by tracking the fatigue state in the structure. Our findings emphasize digital twins’ potential as a valuable tool for renewable energy, driving efficiency and sustainability in offshore floating wind installations. These
aspects, along with the aforementioned simulations, whether in real-time or forecasted, reduce costly and unnecessary inspections and scheduled maintenance
Investigation of the Relationship Between CPT Cone Resistance and Relative Density for a Range of Granular Soils
No full textThis paper presents an investigation of the effects of the properties of reconstituted granular soils on the relationship between CPT cone resistance (qc) and friction angle. The results from a large number of calibration chamber tests conducted at a number of stress levels involving soils with varying shapes, compressibility and mineralogy are presented. The paper also provides data recorded in a parallel series of investigations into the mechanical properties of the granular soils employed in the chamber tests. It is shown that the nature of granular deposits has a strong influence on the relationship between qc and relative density, and that there is a near linear relationship between the cone resistance and the critical state friction angle for sands reconstituted at a given density and stress level
Estimating the fundamental frequency of a sand tailings dam using the H/V spectral ratio method
Get PDFThis study estimates the fundamental frequency of an 85 m height sand tailings dam in Central Chile using the singlestation Horizontal-to-Vertical H/V Spectral Ratio Method (HVSR), calculated from seismic ambient noise and earthquake records. The dam was constructed by compacting hydraulically deposited sands classified from integral copper tailings, following the downstream construction method. A proper estimate of the dam fundamental frequency is critical for evaluating its seismic response and secure the safe tailings containment when subjected to intense ground motions generated by interface and intraslab earthquakes. Results from the HVSR method are compared with those of the Standard Spectral Ratio method (SSR) calculated as the ratio of the response of the dam crest and that recorded at the dam toe. The fundamental frequency of the dam is about 0.9 Hz in the dam central part away from the abutments, but differences in the vibration frequency are identified along the downstream slope and along the crest axis from the north to south abutment. An analytical relationship between the dam fundamental frequency, the dam height, and the shear wave velocity (Vs) profile is validated
MASW Joint Analysis of Rayleigh and Love Waves for Site Characterization
Get PDFThe determination of reliable shear-wave velocity models using Multichannel Analysis of Surface Waves (MASW) has increased importantly for site characterisation studies due to their use in geotechnical studies and regulations. The standard MASW approach is commonly based on the analysis of vertical component of Rayleigh waves, which can result in inaccurate and potentially erroneous interpretations by personal bias. Thus, we present the joint analysis of different and independent multi-component data based on Rayleigh and Love waves to obtain 2D Vs sections for site characterization. Those seismic data were recorded using a landstreamer consisting of 8 triaxial 4.5Hz geophones. To generate Rayleigh waves, the blows were given vertically on a plate, and for the Love waves the blows were given laterally on a horizontal wooden beam. A joint analysis of Rayleigh and Love waves data was conducted on seismic data recorded from the metropolitan area of Granada city (Spain) to generate their dispersion curves. This new approach enabled a proper identification of fundamental- and higher-mode surface waves facilitating the reliable reconstruction of subsurface Vs profiles through a robust joint inversion process. The MASW 1D Vs versus depth models were corroborated at several test sites by the information obtained from boreholes. Thus, the main geological formations could be inferred from MASW 2D Vs sections down to a depth of 30 meters, as well as the Vs30 parameter to perform a reliable seismic microzonation of the study area. This methodology provides a very well constrained inversion procedure capable of providing a robust subsurface Vs model for site characterization
Piezoball and T-Bar Application on a Brazilian Soft Soil Deposit
No full textResearch has already demonstrated advantages in performing piezoball tests when compared to piezocone in estimating the soil undrained shear strength (Su) along the stratigraphy and remolded strength (Sur) through cyclic tests, showing a shorter range of strength correction factors (N) and lower dependence on the soil stiffness index (Ir). Another possible application is estimating the remolded shear strength directly from penetration (qin) and extraction (qext) measurements without requiring cyclic tests. This research performed piezocone, vane, and piezoball tests (standard and cyclic) in a soft soil deposit in southern Brazil. Additionally, undisturbed samples were collected for characterization. The in situ investigation resulted in cone and ball factors in accordance with the international practice recommendation, resulting in similar profiles of undrained strength Su which increases with depth from 3 to 14 kPa and constant values of remolded undrained strength Sur. Regarding estimating the Sur through direct measurements of penetration and extraction of the piezoball, it was necessary to carefully evaluate the time laps between probe insertion and extraction to avoid overestimating the remolded strength