Higher order Whitehead products and L∞L_\infty structures on the homology of a DGL

We detect higher order Whitehead products on the homology $H$ of a differential graded Lie algebra $L$ in terms of higher brackets in the transferred $L_\infty$ structure on $H$ via a given homotopy retraction of $L$ onto $H$.Comment: New references and minor correction

A MCDM methodology to determine the most critical variables in the pressure drop and heat transfer in minichannels

This paper proposes a methodology aiming at determining the most influent working variables and geometrical parameters over the pressure drop and heat transfer during the condensation process of several refrigerant gases using heat exchangers with pipes mini channels technology. A multi-criteria decision making (MCDM) methodology was used; this MCDM includes a mathematical method called SIMUS (Sequential Interactive Modelling for Urban Systems) that was applied to the results of 2543 tests obtained by using a designed refrigeration rig in which five different refrigerants (R32, R134a, R290, R410A and R1234yf) and two different tube geometries were tested. This methodology allows us to reduce the computational cost compared to the use of neural networks or other model development systems. This research shows six variables out of 39 that better define simultaneously the minimum pressure drop, as well as the maximum heat transfer, saturation pressure fluid entering the condenser being the most important one. Another aim of this research was to highlight a new methodology based on operation research for their application to improve the heat transfer energy efficiency and reduce the CO2 footprint derived of the use of heat exchangers with minichannels.Eloy Hontoria is grateful to Project RTI2018-099139-B-C21 financed by FEDER/ Ministerio de Ciencia e Innovación-Agencia Estatal de Investigación

Relación entre precio de alquiler y renta en el mercado residencial español y política de vivienda

[ES] La relación entre los precios de alquiler de vivienda y la renta familiar disponible, o por habitante, para un territorio determinado, es un tema habitual de investigación en el mercado inmobiliario. Presentamos aquí un modelo donde la variable precio de alquiler unitario se explica por la renta mediana, oferta de vivienda plurifamiliar en alquiler, y ratio de esta variable respecto a la población, para secciones censales y municipios. Se calculan también las elasticidades respecto a la renta. Aunque se encuentran relaciones positivas y de cierta significación entre las variables utilizadas, la limitación de la capacidad explicativa del modelo apoya la hipótesis de que el precio en el mercado de alquileres depende, además, de otros factores distintos a los de oferta y demanda, abriendo posibilidades a una política de vivienda. La amplísima base de datos utilizada permite dar cierta generalidad a esta hipótesis de limitación en el funcionamiento del mercado y, al mismo tiempo, muestra la necesidad de desarrollar un mercado con dimensión suficiente, con importantes implicaciones para una política económica de vivienda.[EN] The relationship between housing rental prices and household disposable income, or per capita income, for a particular region, is a common topic of research in the real estate market area. We introduce a model where the square meter rental price is explained by the median income, the supply of multi-family rental housing, and the ratio of this variable to the population, for counties and towns. Income elasticities are also computed. Although positive relationships with some significances are found, the limited explanatory power of the model supports the hypothesis that rental prices also depend on factors other than supply and demand, opening up some possibilities for a housing policy. The very large database used throughout the research allows to support the hypothesis in favor of a constrained performance of the market and, at the same time, shows the need to develop a sufficient sized market, with significant consequences for a housing economic policy.Belchí, A.; Guijarro, F.; Ruiz, G. (2021). Relación entre precio de alquiler y renta en el mercado residencial español y política de vivienda. International Review of Economic Policy Revista Internacional de Política Económica. 3(2):61-76. https://doi.org/10.7203/IREP.3.2.2278761763

Propuesta de un modelo de regresión lineal múltiple para el estudio de la temperatura en pilas de combustible microbianas

[ESP] Se plantea la determinación de un modelo estadístico que nos permita determinar la resistencia interna de una pila de combustible microbiana, ya que este dato nos ayuda a conocer mejor el rendimiento de la misma así como distintas posibilidades en la configuración de su propia tecnología. [ENG] The determination of a statistical model that allows us to determine the internal resistance of a microbial fuel cell will be raised. This model is useful in order to obtain a better understanding of the performance of the fuel cell and different possibilities in shaping their own technology.Centro Universitario de la Defensa. Escuela de Turismo de Cartagena. Escuela Técnica Superior de Ingeniería Industrial UPCT. Escuela Técnica Superior de Ingeniería de Telecomunicación (ETSIT). Escuela de Ingeniería de Caminos y Minas (EICM). Escuela de Arquitectura e Ingeniería de Edificación (ARQ&IDE). Parque Tecnológico de Fuente Álamo. Navantia. Campus Mare Nostrum. Estación Experimental Agroalimentaria Tomás Ferr

Modelling and real-data validation of a logistic centre using TRNSYS®: Influences of the envelope, infiltrations and stored goods

In this paper, the authors aim to support users when modelling scenarios with complex processes entailing thermal loads and infiltrations. The large building analysed is a logistics centre for the replenishment and distribution of perishable foodstuffs where cold chains must be maintained. The logistics centre, with 96 loading/unloading docks, handles large turnovers of different goods. This produces heat inside the facility. Due to continuous loading/unloading, the infiltrations in the building, and the fixed and variable thermal loads, this facility consumes a large amount of energy. Aiming to optimise the centre and contribute to sustainable development goal SDG7, this building has been modelled with a classical non-D envelope using TRNBuild® and also with the more sophisticated 3D software, SketchUp®, to compare and validate their results over a year with real consumption, as well as to assess the main sources of energy consumption. To obtain reliable results, the authors provide some methodology models to identify the sources of the building's thermal losses and quantify the different sources of consumption. These models are useful tools to support decision-makers (to improve insulation and arrange loads, among other things) when trying to reduce energy use in large buildings with intense operating processes. The results indicate that by modelling the entire facility with 3D software, the model estimation differs from real consumption by around 7.22%, while using a non-D model increases the difference to 26%. Additionally, the results show that around 47% of the energy consumption in the building is due to air infiltrations during loading/unloading, 18% is due to perishable products, and around 30% is due to building insulation. The methodology and models presented here, including the possibility of modifying the thermal load profiles, have demonstrated their capacity to reduce and optimise the load demand of refrigeration for warehouses if reliable data records are available.This research was funded by RTI2018-099139-B-C21 from Ministry of Science and Innovation - National Research Agency (MCIN/AEI) 10.13039/501100011033 and by ‘‘ERDF A way of making Europe” of the ‘‘European Union”

Inmovilización enzimática mediante membranas poliméricas de inclusión basadas en líquidos iónicos

[ESP] Los líquidos iónicos presentan una gran utilidad como disolventes y también como medio de reacción, debido a que tienen una presión de vapor prácticamente nula y una alta estabilidad química, mecánica y térmica, lo que permite su reutilización. Se ha desarrollado un derivado enzimático inmovilizado en membranas poliméricas de inclusión basadas en líquidos iónicos para la síntesis de esteres. [ENG] Ionic liquids are very useful solvents as well as reaction medium due to their negligible vapor pressure and high chemical, mechanical and thermal stability, which allow the reuse. An immobilized enzyme derivative in polymeric membranes based on ionic liquids has been developed for the synthesis of esters.Centro Universitario de la Defensa. Escuela de Turismo de Cartagena. Escuela Técnica Superior de Ingeniería Industrial UPCT. Escuela Técnica Superior de Ingeniería de Telecomunicación (ETSIT). Escuela de Ingeniería de Caminos y Minas (EICM). Escuela de Arquitectura e Ingeniería de Edificación (ARQ&IDE). Parque Tecnológico de Fuente Álamo. Navantia. Campus Mare Nostrum. Estación Experimental Agroalimentaria Tomás Ferr

Aplicación de herramientas tecnológicas en el desarrollo de una investigación científica

[ESP] El desarrollo de métodos analíticos más adecuados en lo que respecta a rapidez y economía y el posterior tratamiento de los datos obtenidos, tienen una importancia clave en el progreso de una investigación; no solo para conseguir unas conclusiones claras sino también para transmitir de la forma más diáfana posible los objetivos conseguidos. Con este fin, se ha expuesto el desarrollo de un método cromatográfico y el tratamiento estadístico y gráfico, usando como software SPSS y Mathematica, de los datos obtenidos en un reactor discontinuo equipado con un catalizador biológico diseñado a partir de membranas de inclusión polimérica (PILM) basadas en líquidos iónicos. [ENG] Developing analytical methods in terms of time and economy and post-treatment of the obtained data have a key role in the progress of research; not only for conclusions but also to convey in the clearest possible way the objectives. Thus, the development of a chromatographic method and the statistical and graphical treatment of the data obtained in a batch reactor equipped with a biological catalyst designed from polymeric membranes including (PILM) based on ionic liquids has been exposed using SPSS and Mathematica software Keywords. Gas Chromatography, Ionic Liquid, Mathematica, PILM, SPSS.Centro Universitario de la Defensa. Escuela de Turismo de Cartagena. Escuela Técnica Superior de Ingeniería Industrial UPCT. Escuela Técnica Superior de Ingeniería de Telecomunicación (ETSIT). Escuela de Ingeniería de Caminos y Minas (EICM). Escuela de Arquitectura e Ingeniería de Edificación (ARQ&IDE). Parque Tecnológico de Fuente Álamo. Navantia. Campus Mare Nostrum. Estación Experimental Agroalimentaria Tomás Ferr