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The paradox of the basque farmhouse: The enfolding and unfolding of a cultural infrastructure
Full text linkThis article addresses some of the interpretations that have consolidated the cultural- symbolic-cultural imaginary of the Basque farmhouse, and then broadens the form of approaching the narrative of its identity. From the notion of prototype to that of infrastructure, from anthropological object to artistic object, the Basque farmhouse is conceived as a framework, with an axis open to unfoldings that go beyond the reproduction of its essential image. Concepts related to mediations, performativity and cartography make it possible to track the operativity of this framework, in a process that interweaves different fields of research and controversies that can lead into forms of transdisciplinary, post-qualitative study and cultural innovation.Este artículo aborda algunas de las interpretaciones que han afianzado el imaginario simbólico-cultural del caserío, para, posteriormente, ampliar la forma de acercarse a la narrativa de su identidad. Desde la noción de prototipo al de la infraestructura, del objeto antropológico al objeto artístico, el caserío se concibe como un entramado, como un eje abierto a despliegues que van más allá de la reproducción de su imagen esencial. Conceptos afines al medio, la performatividad y la cartografía proponen el rastreo de la operatividad de esta trama reticular, en un proceso que entrelaza diferentes campos de investigación y controversias que pueden desembocar en formas de estudio transdisciplinares, post- cualitativas y de innovación cultural
Influence of the test-chamber shape on the performance of conductometric gas sensors
Full text linkIn this article, CFD simulations results are presented as a key tool to the comprehension of the target gas concentration evolution in a test chamber, at different working conditions. The simulation results are compared with the experimental data, which shows a qualitative good correlation with the evolution of the concentration gradient detected. The experiments were carried out using an aluminum gas test chamber, where a WO3 based conductometric sensor is introduced. The results demonstrate how the response time is dependent on the sensor working conditions. Analyzing the CFD and experimental results, some assumptions for this behavior are proposed.
The WO3 sensor needs a Pt heating element, which is heated up to 300 °C. As the response is highly temperature-dependent, the temperature distribution on the sensor surface was measured by an IR thermographic camera. The simulation results show that the temperature distribution matches with those obtained experimentally. To validate the model, a mesh and time step convergence study was also implemented
Spatial characterization of the effect of age and sex on macular layer thicknesses and foveal pit morphology
Full text linkCharacterizing the effect of age and sex on macular retinal layer thicknesses and foveal pit morphology is crucial to differentiating between natural and disease-related changes. We applied advanced image analysis techniques to optical coherence tomography (OCT) to: 1) enhance the spatial description of age and sex effects, and 2) create a detailed open database of normative retinal layer thickness maps and foveal pit shapes. The maculae of 444 healthy subjects (age range 21–88) were imaged with OCT. Using computational spatial data analysis, thickness maps were obtained for retinal layers and averaged into 400 (20 x 20) sectors. Additionally, the geometry of the foveal pit was radially analyzed by computing the central foveal thickness, rim height, rim radius, and mean slope. The effect of age and sex on these parameters was analyzed with multiple regression mixed-effects models. We observed that the overall age-related decrease of the total retinal thickness (TRT) (-1.1% per 10 years) was mainly driven by the ganglion cell-inner plexiform layer (GCIPL) (-2.4% per 10 years). Both TRT and GCIPL thinning patterns were homogeneous across the macula when using percentual measurements. Although the male retina was 4.1 μm thicker on average, the greatest differences were mainly present for the inner retinal layers in the inner macular ring (up to 4% higher TRT than in the central macula). There was an age-related decrease in the rim height (1.0% per 10 years) and males had a higher rim height, shorter rim radius, and steeper mean slope. Importantly, the radial analysis revealed that these changes are present and relatively uniform across angular directions. These findings demonstrate the capacity of advanced analysis of OCT images to enhance the description of the macula. This, together with the created dataset, could aid the development of more accurate diagnosis models for macular pathologies
Exploring the applicability of circular design criteria for electric vehicle batteries
Full text linkBattery electric vehicles (BEVs) represent a promising solution to mitigate carbon emissions by road transportation. However, life cycle assessment (LCA) studies on BEVs have demonstrated that batteries are responsible for around 30% of the vehicle’s environmental impacts. Therefore, the integration of circular economy (CE) criteria in battery design and life cycle management is key to improve resource efficiency and environmental sustainability. Nevertheless, literature analysing the implementation of CE design criteria in BEVs´ battery development is scarce. Focusing on Li-ion batteries (LIB) for BEVs, this paper examines the potential for implementation of life cycle-based CE design criteria. Accordingly, a CE design assessment tool, including a list of 53 relevant design criteria gathered from the literature, industrial practice and EU legislation, with application to BEVs´ batteries, was shared with industrial stakeholders from the H2020 LIBERTY project (LC-BAT-10-2020 No. 963522) to receive feedback.
The industrial stakeholders were asked to evaluate the potential implementation of each CE design criteria based on the relationship between importance and viability by providing scores from 0% to 94%.The results indicate that the most important CE design criteria are related to the manufacturing stage of LIBs, including innovations oriented to increase the performance and quality of the final product by anticipating to new legislation requirements, including resource and environmental aspects, for BEVs. On the other hand, design criteria related to the end of life (EOL) management of LIBs show low implementation potential due to low viability scores. The benefits of considering CE design criteria in LIB development are discussed as well as the potential trade-offs in order to support well-informed decision-making. This includes an analysis of the causes for the low score for some CE design criteria and the opportunities to improve their implementation potential to increase the resource efficiency and environmental performance of BEVs´ LIBs
Integration of Hot Isostatic Pressing and Heat Treatment for Advanced Modified gamma-TiAl TNM Alloys
No full textThe conventional processing route of TNM (Ti-Nb-Mo) alloys combines casting and Hot Isostatic Pressing (HIP) followed by forging and multiple heat treatments to establish optimum properties. This is a time-consuming and costly process. In this study we present an advanced alternative TNM alloy processing route combining HIP and heat treatments into a single process, which we refer to as IHT (integrated HIP heat treatment), applied to a modified TNM alloy with 1.5B. A Quintus HIP lab unit with a quenching module was used, achieving fast and controlled cooling, which differs from the slow cooling rates of conventional HIP units. A Ti-42.5Al-3.5Nb-1Mo-1.5B (at.%) was subjected to an integrated two HIP steps at 200 MPa, one at 1250 °C for 3 h and another at 1260 °C for 1 h, both under a protective Ar atmosphere and followed by cooling at 30 K/min down to room temperature. The results were compared against the Ti-43.5Al-3.5Nb-1Mo-0.8B (at.%) thermomechanically processed in a conventional way. Applying IHT processing to the 1.5B alloy does indeed achieve good creep strength, and the secondary creep rate of the IHT processed materials is similar to that of conventionally forged TNM alloys. Thus, the proposed advanced IHT processing route could manufacture more cost-effective TiAl components
Human-centered design for advanced services: A multidimensional design methodology
Full text linkAdvanced services have caught the attention of industries and academics as a way to exploit new customer value propositions. However, the existing design methodologies for advanced services are limited to partially addressing one or some key design elements, hence causing confusion in practice. Moreover, human factors are not often addressed, even though the design for advanced services requires human-centered thinking. Aiming to advance the body of research, the current study aims to conceptually propose a multidimensional design methodology called DIMAND that captures the key design elements and their relations in a single-view structure in accordance with a human-centric approach. Specifically, DIMAND encapsulates the (i) life-cycle service design interrelated with other key design elements—(ii) stakeholder networks, (iii) new service development methods, and (iv) design skills—that must be considered to develop effective advanced service design. Based on a hybrid research design, DIMAND was conceptually developed through systematic reviews and structured analysis of existing design methodologies, as well as an elicitation of expert knowledge in the domain through the analytical hierarchy process (AHP). For validation, the average usability score of DIMAND as evaluated by 26 practitioners was 72.2, which falls into “excellence” on the simplified system usability scale (SUS), hence confirming its potential utility. As a result, DIMAND offers a novel and holistic guideline for design practitioners and engineers to obtain coherence in all the life-cycle design processes by simultaneously taking these key design elements and their relations into account, making the design of advanced services more practical
Demystifying Non-Isolated DC–DC Topologies on Partial Power Processing Architectures
Full text linkThis paper discusses the possibility of achieving partial power processing with non-isolated DC–DC topologies. To this end, partial power converter architectures are seen as an interesting solution for reducing the power processed by the converter. We observed via simulations that single-inductor non-isolated topologies cannot achieve partial power processing since the obtained current and voltage waveforms were the same as those found in a full-power converter. However, when using double inductor non-isolated topologies, reduced current and improved efficiencies were achieved. In order to confirm the results obtained from the simulations, single- and double-inductor topologies were tested experimentally. Finally, it was concluded that a double-inductor non-isolated topology can improve its performance by using partial power processing
Circularity and life cycle environmental impact assessment of batteries for electric vehicles: Industrial challenges, best practices and research guidelines
Full text linkCircular economy (CE) strategies, aimed at reducing resource consumption and waste generation, can help mitigate the environmental impacts of battery electric vehicles (BEV), thereby providing a more efficient alternative to petrol-fuelled vehicles. Lithium-ion batteries (LIB) are commonly used in BEV because of their higher performance than that of the benchmarks. However, how to analyse the CE innovations through life-cycle assessment (LCA) and how environmental savings relate to different CE strategies remain unclear. Therefore, the purpose of this study was to i) identify and characterise the CE strategies most studied thus far in LCA studies on electric vehicle batteries, ii) evaluate the reasons behind the variability in the environmental impacts and savings between LIB with different chemistries, and iii) provide guidelines for the development of robust LCA studies for LIB by integrating CE management scenarios. The results showed that LCA-supported CE strategies have not been sufficiently explored in the literature, causing variability in methodological choices and research outcomes. While battery recycling was a dominant topic contemplated in 80% of the analysed LCA studies, other CE strategies, such as battery upgrading or remanufacturing, received little attention. The normalised impacts for LIB varied from 4400 kg CO2 eq. to 55,000 kg CO2 eq. based on several factors subject to the practitioners’ choices, such as the battery chemistry considered, impact assessment method applied, available inventories used, and the CE scenario analysed. LCA methodological guidelines for determining the environmental sustainability of the CE strategies for electric vehicle batteries were provided based on the findings
Impact performance of out of die UV cured pultruded profiles for vessel structures
Full text linkOut of die ultraviolet (UV) cured pultrusion is an automated process for manufacturing bent profiles that can replace the labour-intensive processes currently employed for manufacturing stiffeners for vessels structures. As the applied pulling forces are lower than in conventional pultrusion, profiles with low longitudinal fibre content can be manufactured, improving the transverse mechanical properties of the pultruded composites. Since impact response is significantly relevant for naval applications, in this paper, the low-velocity impact performance of a multiaxially reinforced UV pultruded profile has been compared to that of a typical pultruded composite. The impact resistance achieved for the multiaxial reinforcement configuration showed an 85% higher perforation energy threshold and a 100% higher maximum peak force than in the reference one. The damage tolerance of the multiaxial configuration was also higher, as when suffering a 30 J impact retained 60% of the stiffness, whereas the conventional pultruded composite only did 45%
Las Junior Cooperativas en la Nueva Ley de Cooperativas de Euskadi
Full text linkLa Ley 11/2019, de 20 de diciembre, de Cooperativas de Euskadi ha incluido en
su regulación a las junior cooperativas como un nuevo tipo de cooperativas señalando que estas «merecen identificación y regulación específicas». La inclusión de las junior cooperativas
dentro de la nueva Ley ha supuesto un paso hacia delante, ya que constituyen de facto, una
nueva clase de cooperativa, distinta del resto de cooperativas contempladas en la Ley. Y es
que, este reconocimiento ha sido necesario, ya que, en la práctica, si bien este tipo de cooperativas ya existían con anterioridad a la aprobación de la Ley, salvo una Instrucción de Servicio dictada por el Registro de Cooperativas, estas carecían de mención y regulación. No obstante, y si bien el reconocimiento normativo ha sido imprescindible, todavía queda camino por
recorrer ya que las junior cooperativas siguen encontrando diversos problemas