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Aquest treball sorgeix d’un projecte anterior on es va dissenyar una màquina per a extreure petits cilindres de fusta de l’interior de llistons arqueològics, procedents de diferents embarcacions que estan exposades en el Museu Marítim de Barcelona (MMB). En aquell projecte, es va fabricar una agulla per a extreure aquestes mostres; en el procés de prova, es va observar que es quedaven encallades a dins i, per tant, s’havien d’extreure mitjançant cops de martell sobre l’èmbol, amb el perill de trencar l’agulla. L’objectiu principal d’aquest projecte consisteix a dissenyar un mecanisme per a facilitar l’extracció de les mostres cilíndriques de dins de l’agulla intentant minimitzar els danys estructurals amb l’ajuda d’una barra que actua com a èmbol. Per al desenvolupament del treball s’ha començat amb la identificació del problema: les altes forces de fricció generades per les superfícies. Per a contextualitzar i definir el projecte, s’han estudiat les diverses embarcacions d’on s’obtindran les mostres així com les seves parts, fustes que les conformen i els seus estats de conservació. També s’exposen les parts i la estructura de la fusta, així com els tipus i les propietats físiques i mecàniques que la defineixen. Contextualitzat el projecte, s’introdueixen i es busquen alternatives a les dues vessants de la solució: la força que s’ha d’exercir sobre l’èmbol i les forces de fricció. Per tal d’empènyer l’èmbol, es van investigar els diversos tipus d’actuadors, seleccionant els mecànics lineals, i es van explicar els principis del seu funcionament coneguts com a mecanismes bàsics. Es realitza una taula comparativa per a la seva posterior selecció. A continuació es fa una breu introducció a les forces de fregament i la seva influència en el problema, i dins de les diferents alternatives trobades, es va escollir, en base a un estudi, la solució consistent en la reducció de les forces de la fricció entre superfícies per les vibracions. Es realitza una investigació de diversos dispositius que generen vibracions i es fa una comparativa dels avantatges i dels inconvenients. Aquesta part inicial finalitza amb una justificació de la selecció dels dispositius que s’incorporen al disseny de la màquina: un mecanisme cargol-femella per al desplaçament lineal i un motor de massa giratòria excèntrica per a generar les vibracions. Després es realitza el disseny global del dispositiu mitjançant modelatge 3D, incorporant aquest dos elements i tenint en compte les dimensions de l’agulla. També es realitzen uns càlculs aproximats del parell torçor que s’ha d’exercir sobre l’èmbol per a trencar-lo a causa del vinclament. A continuació es fabrica, es compra i es munta la màquina dissenyada. Posteriorment es realitzen les proves de verificació del funcionament en fustes toves, com el pi pinyer i en fustes dures com l’om. Es realitza un pressupost i s’expliquen els aspectes mediambientals del projecte. Es conclou el treball confirmant que la màquina realitza les funcions per a les quals està dissenyada i s’afirma que per a les fustes més dures s’ha de realitzar un aparell torçor més gran, ja que les forces de fricció entre les superfícies son més elevades que en les toves, i que les mostres extretes, observades amb una lupa microscòpica, no han patit modificacions estructurals significatives. De l’experimentació, s’han trobat com a millores el disseny d’un peça per a mantenir l’agulla horitzontal, el redisseny de la safata de mostra i un suport per a la immobilització del dispositiu. Este trabajo surge de un proyecto anterior donde se diseñó una máquina para extraer pequeños cilindros de madera del interior de listones arqueológicos, procedentes de diferentes embarcaciones que están expuestas en el Museo Marítimo de Barcelona (MMB). En aquel proyecto, se fabricó una aguja para extraer estas muestras; en el proceso de prueba, se observó que se quedaban encalladas adentro, y por tanto, se tenían que extraer mediante golpes de martillo sobre el émbolo, con el peligro de romper la aguja. Contextualizado el proyecto, se introducen y se buscan alternativas a las dos vertientes de la solución: la fuerza que se tiene que ejercer sobre el émbolo y las fuerzas de fricción. Para empujar el émbolo, se investigan los diversos tipos de actuadores, seleccionando los mecánicos lineales, y se explican los principios de su funcionamiento conocidos como mecanismos básicos. Se realiza una mesa comparativa para su posterior selección. A continuación, se hace una breve introducción a las fuerzas de rozamiento y su influencia en el problema, y dentro de las diferentes alternativas encontradas, se escoge , en base a un estudio, la solución que consiste en la reducción de las fuerzas de la fricción entre superficies por las vibraciones. Se realiza una investigación de varios dispositivos que generan vibraciones y se hace una comparativa de las ventajas y de los inconvenientes. Esta parte inicial finaliza con una justificación de la selección de los dispositivos que se incorporan al diseño de la máquina: un mecanismo caracol-hembra para el desplazamiento lineal y un motor de masa giratoria excéntrica para generar las vibraciones. Después se realiza el diseño global del dispositivo mediante modelado 3D, incorporando estos dos elementos y teniendo en cuenta las dimensiones de la aguja. También se realizan unos cálculos aproximados del par de torsión que se tiene que ejercer sobre el émbolo para romperlo a causa del pandeo. A continuación, se fabrica, se compra y se monta la máquina diseñada. Posteriormente se realizan las pruebas de verificación del funcionamiento en maderas blandas, como el pino piñonero y en maderas duras como el olmo. Se realiza un presupuesto y se explican los aspectos medioambientales del proyecto. Se concluye el trabajo confirmando que la máquina realiza las funciones para las cuales está diseñada y se afirma que para las maderas más duras se tiene que realizar un par de torsión más grande, puesto que las fuerzas de fricción entre las superficies son más elevadas que en las blandas, y que las muestras extraídas, observadas con una lupa microscópica, no han sufrido modificaciones estructurales significativas. De la experimentación, se han encontrado como mejoras el diseño de una pieza para mantener la aguja horizontal, el rediseño de la bandeja de muestra y un apoyo para la inmovilización del dispositivo. This work stems from a previous project in which a machine was designed to extract small wooden cylinders from the inside of archaeological slats from different vessels on display at the Maritime Museum of Barcelona (MMB). In that project, a needle was manufactured to extract these samples; in the testing process, it was observed that they remained stuck inside, and therefore, they had to be extracted by means of hammer blows on the plunger, with the danger of breaking the needle. Once the project has been contextualised, alternatives to the two aspects of the solution are introduced and sought: the force to be exerted on the plunger and the friction forces. To push the plunger, the various types of actuators are investigated, selecting the linear mechanical ones, and the principles of their operation, known as basic mechanisms, are explained. A comparative table is made for further selection. Next, a brief introduction is made to friction forces and their influence on the problem, and among the different alternatives found, the following is chosen The solution consisting of reducing the frictional forces between surfaces by vibrations is chosen on the basis of a study. An investigation of various devices that generate vibrations is carried out and a comparison of the advantages and disadvantages is made. This initial part ends with a justification of the selection of the devices to be incorporated into the design of the machine: a snail-female mechanism for the linear displacement and an eccentric rotating mass motor to generate the vibrations. The overall design of the device is then carried out by means of 3D modelling, incorporating these two elements and taking into account the dimensions of the needle. Approximate calculations are also made of the torque that has to be exerted on the plunger to break it due to buckling. The designed machine is then manufactured, purchased and assembled. Subsequently, tests are carried out to verify its operation in soft woods, such as stone pine, and in hard woods such as elm. A budget is drawn up and the environmental aspects of the project are explained. The work concludes by confirming that the machine performs the functions for which it is designed and states that for harder woods a higher torque has to be applied, since the friction forces between the surfaces are higher than in soft woods, and that the extracted samples, observed with a microscopic magnifying glass, have not undergone significant structural modifications. From the experimentation, the design of a part to keep the needle horizontal, the redesign of the sample tray and a support for the immobilisation of the device have been found as improvements.

The generation of CO2 is an important element in assessing the environmental impact generated in a tunnel construction project, making this knowledge very useful for evaluating different alternatives. In this study, an analysis of the carbon footprint has been carried out, including the main elements during the construction phase of a tunnel employing a tunnel boring machine (TBM). The research proposes several options for an easy and quick calculation of CO2 generation in a design phase. Its determination can be crucial for decision-making before and during the execution of any tunnel in the near future. The estimation models have been validated based on real case studies, defining the carbon footprint of each construction element. The proposed procedure can apply to any tunnel. However, it should be noted that it is an approximate analysis, and the limitations described in each section should be considered. The main CO2 generator found in the construction process is the lining element; the percentage varies between 50% in tunnels with smaller diameters (4–5 m) and 75% for tunnels with larger diameters (9–10 m), followed by the auxiliary elements, 16%, and the operation of the tunnel boring machine itself, 11.2%, while the other parts remain in a range between 1.3 and 5.7%. This knowledge makes it possible to define the aspects on which efforts should be focussed to reduce the carbon footprint of the tunnel construction process. Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura Objectius de Desenvolupament Sostenible::13 - Acció per al Clima Peer Reviewed

This article discusses houses on the periphery of Barcelona and in particular in the El Carmel neighbourhood, which were built by poor country-to-city migrants from southern Spain in the post-World War II period. They were constructed following two typologies: barracas (sheds), one-storey huts on an irregular street plan, and coreas (‘Korea houses’), more formally looking one- to three-storey structures lined up on orderly laid-out streets. Based on archival documents, contemporaneous publications and interviews with former autoconstructores (self-builders), the article analyses both social conditions and physical structures. While these buildings were often unauthorized and constructed by informal means, they were just as often built with the landowner’s consent, involving architects and building professionals, and retroactively legalized. The article concludes that in this respect Barcelona’s ‘informal neighbourhoods’ in fact straddled the realms of the formal and the informal, to the extent that the habitual distinction between formal and informal architecture has to be considered inadequate. Peer Reviewed

Artificial intelligence (AI) generative models driven by the integration of AI and natural language processing technologies, such as OpenAI’s chatbot generative pre-trained transformer large language model (LLM), are receiving much public attention and have the potential to transform personalized medicine. Dialysis patients are highly dependent on technology and their treatment generates a challenging large volume of data that has to be analyzed for knowledge extraction. We argue that, by integrating the data acquired from hemodialysis treatments with the powerful conversational capabilities of LLMs, nephrologists could personalize treatments adapted to patients’ lifestyles and preferences. We also argue that this new conversational AI integrated with a personalized patient-computer interface will enhance patients’ engagement and self-care by providing them with a more personalized experience. However, generative AI models require continuous and accurate updates of data, and expert supervision and must address potential biases and limitations. Dialysis patients can also benefit from other new emerging technologies such as Digital Twins with which patients’ care can also be addressed from a personalized medicine perspective. In this paper, we will revise LLMs potential strengths in terms of their contribution to personalized medicine, and, in particular, their potential impact, and limitations in nephrology. Nephrologists’ collaboration with AI academia and companies, to develop algorithms and models that are more transparent, understandable, and trustworthy, will be crucial for the next generation of dialysis patients. The combination of technology, patient-specific data, and AI should contribute to create a more personalized and interactive dialysis process, improving patients’ quality of life. Peer Reviewed

Climate change indicates that we are heading towards higher temperatures worldwide and greater temperature variations. To face this challenge, we need to adapt to coming conditions and minimize negative impacts on people and the environment. In this paper, we aim to generate evidence to inform decision-making when designing buildings in Switzerland by considering possible future climatic conditions and maximizing the time when buildings do not require neither heating nor cooling systems. We compare two cases, a static scenario where passive systems are permanent (wall and roof thermal insulation), and an adaptable scenario that accounts for movable passive systems (interior shutters, cross ventilation, and solar protection). The results show that the adaptable scenario returns over 1000 hours of free-running conditions more than the static case, both for 2050 and 2070. In the static scenario, the free-running period represents 25% of the year, while in the adaptable scenario it represents around 40%. Thus, passive strategies with movable devices can be a suitable approach to adapt buildings to future climate conditions, which would provide larger periods of free-running conditions, lower energy demand, and lower costs on permanent thermal insulation. Peer Reviewed

Maximizing solar energy production in Switzerland is key to meet energy transition goals. Understanding in detail the current situation, and the potential for expansion is important to develop effective strategies. With this study, we want to contribute to federal and academic efforts to measure solar energy by estimating the net energy produced by photovoltaic (PV) installations when considering their embodied energy. We calculated the values of all energy produced by PV installations across Switzerland from 1991-2021 and subtracted the embodied energy used to manufacture the PV panels and their mounting system. We considered four different types: freestanding, attached-complex, attached-simple and integrated, with progressively decreasing values of embodied energy for the supporting structure. The results show that in 2022, 50% of PV installations were producing net energy, which accounts for an accumulated historical value of 1.000 GWh, implying that 6% of the historical PV generation is net energy. If mounting systems were minimized, the accumulated net energy would reach 23%, showing the importance of integrating PV panels in building elements. These findings suggest that policies to support the diffusion of photovoltaic panels should also ensure long term use of existing installations and consider the mounting systems’ embodied energy for new ones. Peer Reviewed

This paper analyses the impact of urban form and vegetation on one of the most significant parameters that affect people’s thermal comfort and an indicator of urban heat vulnerability: the mean radiant temperature (MRT). To obtain spatialized results and understand in detail the current thermal situation of different public spaces that are part of the city, we combined the SOLWEIG calculation model included in the UMEP tool for QGIS with Urban Weather Generator for Rhino. Six neighbourhoods of Rome (IT) and the associated areas with typical compact urban forms, ranging from historical centre to modern suburbs, have been analysed in the warmest week of the year (August 03-09) during the most critical hours of the day (10 a.m. - 4 p.m.). Georeferenced maps with the mean values of MRT for the studied period allow us to analyse the thermal behaviour of each public square and neighbourhood and locate possible urban havens during heatwaves. This study is part of a larger work that seeks to define a more accurate approach to quantify heat vulnerability within the urban vulnerability indexes, in light of the climate crisis facing cities. Peer Reviewed

Due to the current climate crisis, there is an urgent need to reduce greenhouse gas emissions. Improving façades’ energy performance can significantly reduce the cooling and heating demand of a building. More and more, in warm and mild climates, ventilated façade are given the function of avoiding overheating due to solar radiation and thus reducing the cooling demand of the building. However, this system’s energy performance is not easy to estimate. This study aims to assess the influence of some defining parameters of the ventilated façade on its energy performance. These parameters are not considered in the usual evaluation systems and can be relevant to the envelope’s energy performance. A calculation system has been developed so that architects can use it during the design process to know how their design decisions influence energy performance. Once validated with comparisons with measured values, the calculation system is applied to analyse the influence of some defining parameters of the façade during a warm day in Barcelona: the outer surface’s colour and the dimensions of the ventilation channel. For the studied cases, the change of these parameters implies an important variation in the daily average energy flow traversing the façade. In some cases, it even reverses the direction of the flow, changing from heat gains to heat losses. This concludes that these parameters are relevant to the energy performance of the ventilated façade and that the developed calculation system is a suitable tool to compute it. Peer Reviewed