Operation of a Hybrid Energy Storage System Based on a Cascaded Multi-Output Multilevel Converter with a Carrier-Based Modulation Scheme

Hybrid Energy Storage Systems (HESSs) have gathered considerable interest due to their potential to achieve high energy and power density by integrating different storage technologies, such as batteries and capacitors, to name a few. Among the various topologies explored for HESSs, the multi-output multilevel converter stands out as a promising option, offering decoupled operation of the AC ports while maintaining an internal balance among the diverse storage units. In this paper, the operation and restrictions of a HESS based on a multi-output multilevel converter with a carrier-based modulation scheme are presented. The study provides compelling evidence of the correct operation of the proposed modulation scheme and highlights its advantages, including simplicity and stability.DC systems, Energy conversion & Storag

Hybrid Energy Storage System Based on a Multioutput Multilevel Converter

Energy storage systems (ESSs) allow improving the stability and efficiency of the electrical grids with a high penetration of renewable energy sources. Moreover, the use of Hybrid ESSs (HESSs) enables storage solutions with both high-energy and high-power densities, by combining different storage technologies such as diverse battery chemistries, ultracapacitors, or hydrogen fuel cells to name a few. In this article, an HESS-based multioutput multilevel (MOM) converter is presented. The proposed topology enables decoupled control of each ac converter voltage output. The internal switching states further allow the use of different storage units and high-quality multilevel voltage in each ac output. The mathematical model of the proposed topology and the defined operation region of the system, besides a model-predictive control strategy, are developed. Finally, simulation and experimental results validate the performance of the proposed topology. Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electrical Sustainable EnergyDC systems, Energy conversion & Storag

Rethinking rural prosperity : a discussion of empirical data derived in seven countries with the “Working with People” approach

Farm level changes tend to be connected with alterations in markets (and food chains) on the one side, and with the prosperity of the rural areas in which they are embedded on the other. They are inherently linked to the underlying logics of agro-economic and food systems. Technical 'solutions' often only alleviate the symptoms and ignore wider ramifications. In this paper, we argue that decisions in both, the private and public sector need to pay attention to the systemic nature, and dynamics, of processes, interactions and impacts. The main focus is on rural prosperity, the different ways of understanding the concept and the related parameters and strategies. The discussion incorporates key elements of social learning as well as a range of rural development models. In the analysis, we will examine different farming systems through the "Working with People" model. The basis for the analysis are major case studies from six countries with data from interviews with key actors and stakeholders, focus groups and data on indicators of rural prosperity and wellbeing.Energy & Industr

Autonomous Sensor System for Low-Capacity Wind Turbine Blade Vibration Measurement

This paper presents the design, implementation, and validation of an on-blade sensor system for remote vibration measurement for low-capacity wind turbines. The autonomous sensor system was deployed on three wind turbines, with one of them operating in harsh weather conditions in the far south of Chile. The system recorded the acceleration response of the blades in the flapwise and edgewise directions, data that could be used for extracting the dynamic characteristics of the blades, information useful for damage diagnosis and prognosis. The proposed sensor system demonstrated reliable data acquisition and transmission from wind turbines in remote locations, proving the ability to create a fully autonomous system capable of recording data for monitoring and evaluating the state of health of wind turbine blades for extended periods without human intervention. The data collected by the sensor system presented in this study can serve as a foundation for developing vibration-based strategies for real-time structural health monitoring.DC systems, Energy conversion & Storag

ForceTracker: A versatile tool for contractile force assessment in 3D organ-on-chip platforms

Electronic Components, Technology and Material

Imaging mass spectrometry reveals complex lipid distributions across Staphylococcus aureus biofilm layers

Introduction: Although Staphylococcus aureus is the leading cause of biofilm-related infections, the lipidomic distributions within these biofilms is poorly understood. Here, lipidomic mapping of S. aureus biofilm cross-sections was performed to investigate heterogeneity between horizontal biofilm layers. Methods: S. aureus biofilms were grown statically, embedded in a mixture of carboxymethylcellulose/gelatin, and prepared for downstream matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS). Trapped ion mobility spectrometry (TIMS) was also applied prior to mass analysis. Results: Implementation of TIMS led to a ∼ threefold increase in the number of lipid species detected. Washing biofilm samples with ammonium formate (150 mM) increased signal intensity for some bacterial lipids by as much as tenfold, with minimal disruption of the biofilm structure. MALDI TIMS IMS revealed that most lipids localize primarily to a single biofilm layer, and species from the same lipid class such as cardiolipins CL(57:0) – CL(66:0) display starkly different localizations, exhibiting between 1.5 and 6.3-fold intensity differences between layers (n = 3, p < 0.03). No horizontal layers were observed within biofilms grown anaerobically, and lipids were distributed homogenously. Conclusions: High spatial resolution analysis of S. aureus biofilm cross-sections by MALDI TIMS IMS revealed stark lipidomic heterogeneity between horizontal S. aureus biofilm layers demonstrating that each layer was molecularly distinct. Finally, this workflow uncovered an absence of layers in biofilms grown under anaerobic conditions, possibly indicating that oxygen contributes to the observed heterogeneity under aerobic conditions. Future applications of this workflow to study spatially localized molecular responses to antimicrobials could provide new therapeutic strategies.Team Raf Van de Pla

Between aspirations and reality: Making farming, food systems and rural areas more resilient, sustainable and equitable

This paper explores the connections between farm modernisation, rural development and the resilience of agricultural and rural systems. The paper starts by ascertaining why agricultural and food systems need to change systemically. Evidence from case studies in fourteen countries is used to explore the possibilities for, and drivers and limitations of systemic change in four thematic areas: the resilience of farms and rural areas; prosperity and well-being; knowledge and innovation, and; the governance of agriculture and rural areas. In each area, we identify a major mismatch between visions and strategies on the one hand, and market developments, policy measures and outcomes on the other. The first theme is of growing concern as there has been an observable decrease in the social-ecological resilience of farms and of rural communities in recent decades. The second theme emerges as important as the concentration of production in some regions or some farms is directly linked to the marginalisation of others. The third theme illustrates that local farmer-driven innovations can teach us much, especially since farmers focus on efficiently using the resources available to them, including their location-specific experiential knowledge. Through the final theme we show that informal networks can balance different interests and approaches, which is essential for integrated rural development strategies and projects. Our findings in these four thematic areas have implications for the strategic frameworks and policy of the EU (and beyond) and future research agendas. We explicitly draw these out. The 14 case studies show that practitioners, grassroots initiatives and pilot programmes are already generating a wealth of experiences and knowledge that could be fruitfully used to inform higher-level policy development. The paper concludes that systemic change requires more critical reflection of conventional wisdom and approaches, and openness to ideas and practices that are outside the mainstream.Energy & Industr

Kiloparsec-scale Imaging of the CO(1-0)-traced Cold Molecular Gas Reservoir in a z ∼3.4 Submillimeter Galaxy

We present a high-resolution study of the cold molecular gas as traced by CO(1-0) in the unlensed z ∼3.4 submillimeter galaxy SMM J13120+4242, using multiconfiguration observations with the Karl G. Jansky Very Large Array (JVLA). The gas reservoir, imaged on 0.″39 (∼3 kpc) scales, is resolved into two components separated by ∼11 kpc with a total extent of 16 ± 3 kpc. Despite the large spatial extent of the reservoir, the observations show a CO(1-0) FWHM linewidth of only 267 ± 64 km s-1. We derive a revised line luminosity of LCO(1-0)′ = (10 ± 3) × 1010 K km s-1 pc2 and a molecular gas mass of M gas = (13 ± 3)× 1010 (α CO/1) M ⊙. Despite the presence of a velocity gradient (consistent with previous resolved CO(6-5) imaging), the CO(1-0) imaging shows evidence for significant turbulent motions that are preventing the gas from fully settling into a disk. The system likely represents a merger in an advanced stage. Although the dynamical mass is highly uncertain, we use it to place an upper limit on the CO-to-H2 mass conversion factor α CO of 1.4. We revisit the SED fitting, finding that this galaxy lies on the very massive end of the main sequence at z = 3.4. Based on the low gas fraction, short gas depletion time, and evidence for a central AGN, we propose that SMM J13120 is in a rapid transitional phase between a merger-driven starburst and an unobscured quasar. The case of SMM J13120 highlights how mergers may drive important physical changes in galaxies without pushing them off the main sequence. Tera-Hertz Sensin

. 37. Arqueología

Reciban nuevamente un cordial saludo del equipo de la revista Arqueología. En esta ocasión nuestros colaboradores han puesto en la mesa una serie de trabajos interesantes que dan cuenta de la variedad de temas y derroteros de la investigación arqueológica en México. Los trabajos, cada vez menos dependientes del manejo descriptivo de materiales arqueológicos, sobre todo los cerámicos, incursionan en aspectos bioculturales, innovaciones técnicas y, felizmente, en analogías etnográficas. Siguiendo el orden acostumbrado, la primera aportación es un trabajo pionero de Grave Tirado, el cual, como producto de las primeras investigaciones arqueológicas sistemáticas en la zona serrana del sur de Sinaloa, ofrece información novedosa sobre sitios y materiales hasta ahora no descritos, así como su ya acostumbrada interlocución con la información etnohistórica. La presencia de juegos de pelota, que ya había sido notada por otros investigadores de la sierra, la gráfica rupestre y los materiales, nos guía por esa —hasta ahora poco trabajada— “tradición serrana” que alguna vez intentó definir Beatriz Braniff. También del Occidente, pero de amplia temporalidad, tenemos la contribución ofrecida por Gómez Valdéz y sus asociados, donde se refuerza una visión integrativa-evolutiva de la población mesoamericana a través de un análisis estadístico y comparativo de la variabilidad de su morfología dental con otras poblaciones de la Mesoamérica nuclear. La conclusión a la que llegan es que el aislamiento genético de los periodos tempranos se convierte en una continuidad genética ya en las fases tardías. El siguiente trabajo, de VanDerwarker y Jaime-Riverón, está centrado en el análisis de los restos botánicos de los sitios formativos de La Joya y Bezoapan, en la zona de Los Tuxtlas, para establecer una cronología de los cambios en la proporción de productos agrícolas y de la silvicultura. Con base en el modelo de agricultura tropical de Killion y Peters, discuten también la relación de las prácticas de explotación del medio con las áreas de habitación. Aun cuando este artículo ya había sido publicado en inglés, consideramos que su inclusión en nuestra revista puede promover discusiones provechosas. En relación con el área maya, cuyos investigadores son siempre tan productivos, tenemos varias aportaciones. En la primera de ellas, y con datos de su participación en la investigación en el sitio de Chunchukmil, en Yucatán, Woynar construye una propuesta sobre organización y estructura espacial a través del análisis de las implicaciones sociales de las 666 vías de comunicación —tanto internas como externas—, y corresponde al Clásico el nivel más alto de cohesión y planificación. A su vez, Ortega Palma realiza un estudio bioantropológico comparativo sobre dos series de restos óseos procedentes, respectivamente, de la isla de Jaina para el Clásico tardío y de la ciudad de Campeche para la época colonial. El propósito del autor es comparar condiciones de salud y alimentación a partir de los agentes que influyeron en dichas variables en función de factores geográficos, sociales, económicos y culturales. A continuación presentamos un texto de corte técnico y orientado a la detección de sitios para ayudar en el trabajo de prospección en zonas de selva tropical —lo que queda de ellas —; así, la contribución de López García y Argote Espino, aboga por utilizar imagenes remotas de alta definición y sistemas de procesamiento digital para el reconocimiento de sitios con arquitectura monumental en áreas donde el desarrollo de selvas altas impide el uso de la foto aérea convencional. Asimismo, contamos también con varios artículos acerca del Altiplano. Nalda nos proporciona información de un horno prehispánico para quemar cal localizado en el sitio Hacienda de Calderón, Morelos. Después de presentar los datos de campo, el investigador establece una serie de parámetros de observación etnográfica que le permiten ampliar la discusión e interpretación del elemento arqueológico, cuya cronología establece como posterior al año 750 d.C. En la misma región, pero entrando de lleno en el Epliclásico, González Crespo y sus colaboradores presentan una amplia discusión sobre la cronología de Xochicalco, con base en una recapitulación de sus componentes arquitectónicos y asociándolos a las etapas constructivas del sitio en función de los sistemas constructivos, cerámica y fechas disponibles de C14. Su conclusión es que el sitio corresponde enteramente al Epiclásico. Seguimos con el Posclásico en Cholula y presentamos la propuesta interpretativa de Araceli Rojas sobre iconografía solar en la cerámica policroma tipo códice. Su análisis la lleva a ligar su uso al contexto ritual, pero también a su función simbólica de prestigio entre las elites mesoamericanas, sin excluir la posibilidad que se trate de vajilla de servicio. Finalmente, nos complace compartir con ustedes el trabajo que el joven equipo de Spores nos ofrece sobre el sitio de Yucundaa, Teposcolula, Oaxaca. Una rica exposición de datos, su discusión y propuestas sobre este asentamiento y sus transformaciones del Posclásico tardío a la Colonia. El diálogo constructivo entre fuente y arqueología permite acercarse al momento de transformación y resistencia que implica la Colonia temprana, desde la perspectiva del pueblo indígena y no sólo desde los elementos arquitectónicos coloniales religiosos. No menos interesantes resultarán nuestras otras secciones —noticias, reseñas, archivo técnico e In memoriam—, cuyos variados contenidos les invitamos a descubrir. No queda sino reiterar el llamado —la provocación— a demostrar nuestra productividad y calidad académica mediante la discusión pública de las propuestas, aportaciones y críticas emanadas de nuestro diario ejercicio profesional</p