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Transició energètica: Elements per a millorar-ne la governança
No full textTRANSICIÓ ENERGÈTICA. ELEMENTS PER A MILLORAR-NE LA GOVERNANÇA
Coautors
Xavier Farriols Solà
Francesc Reventós Puigjaner
Proposta 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
Rethinking the institutional framework to manage droughts
No full textAs water is a complex resource essential to human life and numerous activities, which largely departs from the characteristics of both public and private good, governance around its allocation and reallocation for different uses is not trivial. This explains why specific institutions have historically emerged to manage the resource or resolve conflicts arising from the multiple uses that compete with each other. It would be the case of the Water Court of Valencia or the Hydrographic Confederations. These specific institutions must interact with the traditional administration (in Spain, the central government, the autonomous communities and local bodies, which interact in a complex map of competences) and with private or mixed operators where appropriate, as well as with communities of irrigators, operators of energy conversion plants and other groups. The recurring drought episodes in Spain and Catalonia, more frequent and intense as a result of climate change, suggest the importance of thoroughly analyzing how the existing institutions have dealt with these episodes, and detecting dysfunctions and aspects to be strengthened. Climate change, in fact, amplifies a pre-existing phenomenon in much of the territory: drought is the acute manifestation of a structural challenge (long-term water scarcity), therefore, the institutional framework that addresses it it is as important as technological advances or investments to deal with it. Our contribution will make proposals along the lines of a federal improvement of the existing institutional framework, with a special focus on Catalonia, but with a Spanish and European perspective as well, to deal with the risk of drought, specific drought events and to advance the water security in a context of inevitable adaptation to climate change.
Francesc Trillas (UAB) and Gonzalo Delacámara (IE)
 
Comparative Liquefaction Triggering Assessment of Gravelly Reclamations using the CPT, DPT, and Shear-Wave Velocity
Get PDFMajor challenges are encountered in characterizing and performing liquefaction assessment of gravelly soils since performing traditional in-situ tests, such as the Cone Penetration Test (CPT), in gravelly soils can be challenging, and since gravelly soils are not well-represented in existing case history databases used to develop semi-empirical methods for liquefaction assessment. This has been the primary reason for the ongoing efforts to develop methods based on other invasive tests, such as shear-wave velocity (Vs), and penetration tests with larger probes and greater energy delivered to the rod, such as the Dynamic Cone Penetration Test (DPT). While CPT-based liquefaction analyses have been comprehensively studied, limited research has been conducted comparatively evaluating the performance of the other two methods. This paper performs liquefaction triggering assessment of gravelly reclamations using data from the welldocumented case history of the port of Wellington (New Zealand) using CPT, DPT, and Vs measurements. Results show that while the Vs measurements overestimate liquefaction resistance, the DPT and CPT agreed relatively well with observations from past earthquakes due to the greater sensitivity of these test methods to soil density and stratigraph
Comparison of Pore Pressure Parameters from Piezocone and Dilatometer
Get PDFThe Piezocone (CPTU) and the Marchetti Flat Plate Dilatometer (DMT) provide a number of empirical correlations for the purpose of soil identification. Each tool has defined a pore pressure parameter. For the piezocone, the parameter Bq ‘is based on the penetration pore pressures, the corrected tip resistance, the total overburden stress, and the existing hydrostatic pore pressure. This index has been used to characterize soil behavior rather than the actual soil type. For the dilatometer, the parameter Ud is based on the corrected pressures p0 and p2, calculated using the A and C readings and the existing hydrostatic pore pressure. This index can be combined with the material index ID to help with soil identification. Results from several test sites provide a promising direct correlation between Bq and UD, which can be used to enhance the identification of soil types by simply using the C-reading when performing DMT tests. Although the C-reading has been grossly ignored by users of the DMT, this new development will encourage measurement of this reading which provides similar trends to the pore pressures measured by the CPTU. The latest DMT equipment allows for the automatic measurement of the C-reading, which will assist in developing and enhancing existing correlations. This paper will present results at test sites located on opposite coasts of the USA. The trends of the Bq and UD indices are shown to be remarkably similar in all types of soils
SDMT VS profiles in heterogeneous granular soil deposits
Get PDFMany urbanized areas of the Apennines, in Italy, have complex soil stratifications. A typical example is the historical center of L'Aquila and its outskirts, founded on layers of significantly heterogeneity and struck by a strong earthquake in 2009. Under these conditions, shear wave velocity profiles (VS) obtained from in-situ measurements using SDMT techniques allow reliable analyses of local seismic response. In the soil of L'Aquila, the use of SDMT tests in sand-filled boreholes, following the procedure described by Totani et al. (2009), allowed VS to be measured at considerable depths. This article presents the results of local seismic response analyses conducted to characterize the soil foundation of the hospital complex and adjacent university buildings in L’Aquila before their seismic retrofitting. The authors developed a soil model based on the Vs profiles retrieved from the SDMT tests. This approach provided a detailed understanding of the soil seismic behaviour, essential for the proper characterization of seismic action and consequently, the design of seismic interventions. The study emphasises the importance of accurate soil characterisation prior to seismic upgrades especially in deposits where there are multiple shear wave velocity inversions. The seismic demand coming from the Italian Building Code of 2018, based on the so-called soil categories from equivalent velocity of shear wave, was compared to the results of the local seismic response analysis conducted by using the real Vs profiles from SDMT, which are extended to a much greater depths than those generally required by the regulations
Development of liquefiable zone mapping using semi-empirical methods
Get PDFOne of the most significant processes in soil dynamics is liquefaction. It is a loss of strength coupled by a quick increase in pore pressure, causing soil particles to break apart for a brief period. There have been several approaches published for calculating the residual or liquefied shear strength of cohesionless soils. This article gives cone penetration test relationships for assessing vulnerability to loss of strength and liquefied shear strength in a variety of soils. Then, based on the results of our studies, we were able to map the liquefiable zones of the Mnasra region, located in the Gharb basin and extending over an area of 4000 km2, which is characterized by two main facies: (i) a predominantly gravelly and/or conglomeratic facies, separated by silt-clay levels (east of the nappe), (ii) a predominantly sandy, sandstone and calcareous facies, separated by silt-clay levels (coastal zone and southern sector on the Maâmora side). IPL calculations predict a spatial-temporal variation in liquefaction at depths ranging from a low probability of liquefaction to a certaint
Multivariate Gaussian Process for 3D subsurface stratigraphy prediction from CPT and labelled borehole data
Get PDFQuantifying uncertainties in subsurface properties and stratigraphy can lead to better understanding of the ground conditions and enhance the design and assessment of geotechnical structures. Several studies have utilized Cone Penetration Test (CPT) data and employed Bayesian and Machine Learning methods to quantify the geological uncertainty, based on the Robertson’s soil classification charts and the Soil Behaviour Type Index (Ic). The incorporation of borehole data can reduce the stratigraphic uncertainty. Significant challenges can arise, however, mainly due to the intrinsic differences between field and laboratory-based soil classification systems, which can potentially lead to inconsistent soil classification. To this end, this study proposes a multivariate Gaussian Process model that utilizes site-specific data and: i) jointly models multiple categorical (USCS labels) and continuous (Ic) variables, ii) learns a (shared) spatial correlation structure and the betweenoutputs covariance, and iii) produces two types of dependent classification outputs. The results indicate that the integration of geotechnical and geological information into a unified model can provide more reliable predictions of the subsurface stratification, by allowing simultaneous interpretation of USCS and Ic profiles. Importantly, the model demonstrates the potential to integrate multiple variables of different types, aiming to contribute to the development of a methodology for joint modeling of geotechnical, geological and geophysical data
Integrating Digital Platforms and Positive Psychology: A Web App for Enhancing University Student Well-being
No full textThe contemporary digital landscape offers unparalleled opportunities for educational innovation, particularly in enhancing student well-being through digital platforms. This proposal outlines a web app developed under the European project Happy Power, designed to improve university students' well-being by integrating Positive Psychological Interventions (PPIs) with user-friendly digital solutions. This app addresses common psychological challenges such as stress and loneliness, which are significant barriers to student success.
Drawing on the findings from "Positive Psychological Interventions (PPIs) in the age of COVID-19: on the potential impact of digital PPIs on loneliness" (Parks & Boucher, 2020), the app uses digital means to deliver psychological benefits remotely. It incorporates elements such as gamification and interactive features to encourage engagement and sustained usage, thereby enhancing students' educational experiences and psychological resilience.
Additionally, the integration of this tool into the university curriculum supports the emergent needs for digital literacy and educational innovation, reflecting broader economic and societal shifts towards digital transformation. This initiative aligns with the principles described in "Positive education: positive psychology and classroom interventions" (Seligman et al., 2009), advocating for an educational paradigm that balances psychological well-being with academic achievement.
Moreover, recent research by Kounenou et al. (2022) highlights the effectiveness of a 5-week group-based PPI in enhancing positive emotions, resilience, happiness, optimism, and self-esteem among university students. This study supports the app's approach by demonstrating that structured PPIs can effectively improve well-being and mental health outcomes in educational settings. The integration of various exercises such as gratitude letters, optimistic thinking, replaying positive experiences, and socializing, as evidenced in the study, can be adapted for digital delivery through the app, providing a scalable model to enhance student well-being.
The development and implementation of this web app within the academic setting are anticipated to not only improve individual student outcomes but also contribute to a more supportive and productive educational environment. The use of evidence-based PPIs in higher education, as demonstrated by the study's success in Greece, suggests that similar digital interventions can be beneficial globally. This represents a significant step towards integrating scientific insights from positive psychology with digital innovation, offering a scalable model for enhancing student well-being through technology
Upgrading a resonant column apparatus to reliably measure specimen void ratio
Get PDFThe small strain shear modulus of soils is an important design geotechnical parameter for a wide range of civil infrastructure applications. The small strain shear modulus can be determined by using elastic theory as a relationship between the soil density, which is expressed as a function of void ratio, and the measured shear wave velocity. Thus, the void ratio has a fundamental impact on the accuracy of the result. Laboratory testing involving resonant column apparatus allows for determining the changes in stiffness of soils with varying void ratios. Standard of-the-shelf resonant column apparatus works well for clayey soils but presents a number of limitations for coarse soils that makes accurate and reliable void ratio measurement difficult due to both pore fluid and (often) sample loss during removal from the equipment. This paper presents the development of a modular set-up which allows for complete specimen sealing at the end of shear wave velocity testing. The modular set-up along with the specimen can be removed from the resonant column apparatus and the void ratio can be determined by means of end-of-test-freezing similar to triaxial testing. From this, reliable small strain stiffness at well-determined void ratio can be computed. The void ratio measurements using the new modular set-up were compared to those from triaxial tests performed on identically prepared specimens. The difference in void ratio at any given isotropic confining stress was between 0.001 and 0.011
Influence of hydrogeological conditions on estimation of undrained shear strength by CPTu tests: case study in a tropical soil
Get PDFCPTu tests have gained prominence in the geotechnical characterization of materials, registering a significant increase in their application in the Brazilian context, especially due to requirements to consider undrained resistance in analyses guided by more recent regulations. However, the interpretation of these tests often lacks a detailed and personalized approach, as they disregard specific nuances of each location. In this study, the foundation of a dam made up of tropical soil with a specific hydrogeological condition, characterized by bottom drainage with deep percolation, previously identified in other research campaigns, was evaluated. The interpretation of the CPTu test aimed to estimate the undrained resistance of the material through two different approaches: considering the dissipation tests carried out to model the insitu pore pressure according to the elevation versus a hypothetical hydrostatic condition, which could be misinterpreted in places where there is a predominance of SPT tests and insufficient geological knowledge. Multiple methodologies were evaluated to interpret undrained shear strength, including approaches that use Bq directly and that exclusively considers the laboratory characterization of a sample and the overconsolidation ratio at that point. In this case analyzed, it was observed that the change in pore pressure conditions resulted in a considerable variation in the undrained shear strength ratio, over 10% when pore pressures are considered in the equations. The results highlight the relevance of considering local hydrogeological conditions when interpreting field tests, especially for foundations of large structures