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Abstract Conventional spouted beds have been extensively used in many real-life applications but are not suited for all types of materials, especially fine particles, which require internal devices to improve their motion in the spouted bed. However, unlike conventional spouted beds, there are almost no mechanistic or empirical models available for the design of spouted beds with internals. Given the availability of an extensive but not experimentally designed database, the main purpose of this study is to present an analysis of neural networks and empirical models in terms of their suitability to fit and predict average cycle times in conical spouted beds with and without draft tubes. The parameters investigated are particle size, density, contactor angle, gas inlet diameter, static bed height, and draft tube features. Although the amount of information is always a key factor when fitting models, the size of the database used in this study strongly affects the fitting performance of empirical models, whereas artificial neural networks are more influenced by how the data are scaled. Results of model verification show that both techniques are suitable for predicting average cycle times for data outside the range covered by the database.

In the past decade, inverter-integrated energy sources have experienced rapid growth, which leads to operating challenges associated with reduced system inertia and intermittent power generation, which can cause instability and performance issues of the power system. Improved control schemes for inverters are necessary to ensure the stability and resilience of the power system. Grid-forming inverters dampen frequency fluctuations in the power system, while grid-following inverters can aggravate frequency problems with increased penetration. This paper aims at reviewing the role of grid-forming inverters in the power system, including their topology, control strategies, challenges, sizing, and location. In order to facilitate continued research in this field, a comprehensive literature review and classification of the studies are conducted, followed by research gaps and suggestions for future studies.

Considerando-se a preocupação crescente com a toxicidade dos efluentes, pela presença de metais e a ocorrência de novos poluentes orgânicos, esse estudo aplicou o Processo Oxidativo Avançado (POA) de fotoeletrooxidação (FEO) como polimento para o efluente após o processo convencional de tratamento de efluentes da indústria metalomecânica, que, muitas vezes, não remove, satisfatoriamente, metais e aditivos orgânicos. A FEO associou, à degradação de aditivos orgânicos, a remoção do níquel. Foram avaliados efluentes sintéticos com composição similar a efluentes do processo de eletrodeposição de níquel contendo aditivos. Empregando o ânodo de Ti revestido com 70%TiO2/30%RuO2 sob incidência de radiação UV de uma lâmpada de vapor de mercúrio de 250 W e um cátodo de aço inox, 2,5 L de efluente foram tratados em um reator de 1,6 L, com vazão de recirculação de 1 L.min-1. Aplicando diferentes densidades de corrente, observou-se redução da DQO de até 83% e remoção de Ni acima de 90%. Os ensaios de citotoxicidade indicaram que a FEO não gerou intermediários mais tóxicos, pois não ocorreu aumento do efeito tóxico na comparação das soluções antes e após a FEO.

Las filosofías de la Pachamama y del Buen Vivir son puntos de referencia de los pueblos indígenas y están presentes en las constituciones de Ecuador (2008) y Bolivia (2009), con el fin de armonizar las diferencias culturales y añadir las tradiciones a la política local. Las filosofías toman por base un mito andino, el que cree ser la naturaleza un organismo vivo y sujeto de derechos, y se abren espacio a la visión biocéntrica del mundo, compartida por la Bioética Global. La naturaleza ya no logra recomponerse por las innovaciones biotecnológicas impuestas por el hombre, lo que obliga la humanidad a encontrar nuevos paradigmas – el Nuevo Constitucionalismo Latinoamericano, representado por las constituciones de Ecuador e Bolivia, es uno de ellos. En este artículo se describe y analiza críticamente estas dos constituciones, relacionándolas con la visión de mundo de la Pachamama y de la filosofía del Buen Vivir en el contexto de la Bioética Global.

Through the realization of research, development and innovation projects, several technological advances in society were possible, provided by the generation and application of knowledge in systematized way. These projects are generally materialized in specialized institutions in the development of high-level scientific solutions aimed at increasing intellectual and material corporate, governmental or social power. Within organizations, in view of the current increasingly globalized competitiveness, the decision-making process is fundamental. In this perspective of search for continuous improvement, it is essential the vision of the future by managers and researchers as well as the industry, so that they work integrated and articulated. In addition, governments and companies have suffered from political and economic crises that, with the use of techniques such as structural analysis and strategic prospecting, would be possible to be premeditated and better managed. Therefore, this dissertation project proposes an approach to scenario exploration for the Institute for Smart Grids at Federal University of Santa Maria, which carries out research, development and innovation activities. This research is based on a bibliographical and documentary review on the characteristics of the sector, competitive intelligence and scenario exploration. This work listed a set of 54 variables of impact in the system studied, identified nine key variables to receive priority attention and the 10 groups of actors that command them. Through the identification of the objectives of these actors, a structure of power relations has been demonstrated that can be taken into account in the creation of present and future scenarios. This dissertation compiles several strategic aspects and how this information can be visualized to enhance the understanding of the research, development and innovation environment for the Institute for Smart Grids. ; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES ; Através da realização de ...

Eucalyptus is the main fast-growing tree for biomass production in the tropics, providing resources for pulp and paper industries and bioenergy. The potential productivity of forest sites over an eight-year rotation in Brazil was evaluated by the Physiological Principles in Predicting Growth (3-PG) model for two soils, Acrisols and Arenosols, with high and low water storage, respectively, and distinct productive potential capacity. The model was parameterized by data-sets obtained in bimonthly forest inventories performed in stands with 33, 58 and 89 months-old trees, and edaphic surveys. The average volumetric productivity of wood and biomass of the main stem determined at the 89 months-old stand was 374 m3 ha−1 (177 Mg ha−1) for Acrisols and 272.3 m3 ha−1 (130.0 Mg ha−1) for Arenosols. The estimated volumetric production in the Arenosols had a high mean annual increment up to the age of 58 months, with a significant reduction in growth rates after this time. In Acrisols, high incremental rates in wood volume up to age of 89 months (MAIVW > 50 m3 ha−1 year−1) indicate that, under ideal soil conditions, the cutting cycle may exceed 8 years with no productivity impairment. The parameterized model matched well for forest yield (r2 > 0.9) and dendrometric variables (r2 > 0.78). The expected results of lower productivity in Arenosols occurred only after 58 months, while for Acrisols productivity remained high up to 89 months. The results showed the eucalyptus cycle should be shorter in Arenosols, since the lower cutting cycle can provide higher final productivity, when using the mean annual increment to evaluate productivity.

This work evaluates, for the first time, the possibility of producing multifunctional alkali-activated composites combining ultra-low density, low thermal conductivity, high acoustic absorption, and good moisture buffering capacity. The composites were prepared using cork as a lightweight aggregate. This novel material might promote energy savings and tackle the CO2 emissions of the building sector, while simultaneously improve the comfort for inhabitants (e.g. humidity levels regulation and sound pollution reduction). The composites apparent density (as low as 168 kg/m3) and thermal conductivity (as low as 68 mW/m K) are amongst the lowest ever reported for alkali-activated materials (AAM) composites and foams, while their sound absorption ability is comparable to the best performing AAM foams reported to date, but in addition these eco-friendly composites also show good ability to passively adjust the humidity levels inside buildings. The multifunctional properties shown by the cork – AAM composites set them apart from other conventional building materials and might contribute to the global sustainability of the construction sector. Peer Reviewed