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Este trabajo se centra en el modelado mediante TRNSYS de una bomba de calor geotérmica agua-agua que utiliza CO2 como refrigerante para producir agua caliente sanitaria (ACS), para posteriormente hacer un estudio comparativo con una instalación solar. Dicha instalación se encuentra disponible en el laboratorio de Calor y Frío del ELDI. Los objetivos principales del trabajo son: - Estudiar y entender el funcionamiento de la bomba de calor y de todos sus componentes. - Conocer las ventajas que presente el CO2 como refrigerante. - Búsqueda de información acerca de los sistemas de captación de energía geotérmica. - Modelar los componentes que constituyen una bomba de calor geotérmica. - Programar los modelos seleccionados mediante el compilador FORTRAN. - Simulación de la bomba de calor en TRNSYS a partir de los componentes programados que la forman. - Realizar un estudio comparativo con un sistema solar convencional a base de colectores solares. ; Escuela Técnica Superior de Ingeniería Industrial ; Universidad Politécnica de Cartagena

The objective of this work is to valorise the discharges (rejections) of the Boukhedra iron ore mine (east of Algeria) as raw materials for the elaboration of the cement raw. The study concerns the development of different types of low impact environmental belite cements whose raw are exclusively mine rejections. The use of a low CaO / SiO2 ratio and the combination of quick cooling of clinker with adequate NaF and LiF mineralization in association with CaSO4, has led to the production of belite cement with high hydraulic reactivity comparable to that of ordinary Portland cements. The used mineralization plays also a positive role in improving performance in terms of firing of the raw, by lowering the clinker process temperatures of these cements, thus, enabling an additional gain in terms of environmental impact and energy consumption. This mineralization and the low LSF of these cements allows obtaining them at low burning temperatures 1150 °C and 1100 °C for the cement with 2%LiF. This is 350 °C lower to ordinary Portland cement. The addition of CaSO4, NaF and LiF to the clinkers makes the improvement of its clinkering possible. The effect of LiF seems to be the most significant followed by NaF and finally, CaSO4

FAERE Working Paper, 2019.23 ; While environmental values are spreading among societies, theyhardly lead to effective political actions. This may be due to an overestimation of the sharing of those values among people, or to a lack ofpolitical power of environmentalists vis-à-vis materialist citizens. Wepropose a theoretical model to investigate these two channels, based ona setup a la Grossman and Helpman (1994), in which lobby is a strategy available to social groups, in order to influence the government onenvironmental taxes. Because societies have being historically markedby materialist habits, citizens sharing those habits face lower costswhen getting organized. By considering endogenous lobby formation ala Mitra (1999), we show that, in order for environmental and materialist lobbies to coexist, the society must be mixed enough. Based on adynamic framework a la Besley and Persson (2019), we investigate howsocial values change over time. Whenever lobbying by materialists prevails, a unique social equilibrium exists, featuring a stable hegemonyby materialist values. If environmentalists get organized too, a secondsocial equilibrium emerges, that is locally stable and more favorableto them. However, the threshold might be very high, above which thecultural transition effectively takes off. By calibrating the model, westudy counter-acting forces allowing to improve the odds of the environmental transition, such as cultural mutations, social-signaling, andlowering organizational costs. Finally, we provide policy implications. ; Alors que les valeurs environnementales se répandent dans les sociétés, elles ne débouchent guère sur des actions politiques efficaces. Cela peut être dû à une surestimation du partage de ces valeurs entre les gens, ou à un manque de pouvoir politique des écologistes vis-à-vis des citoyens matérialistes. Nous proposons un modèle théorique pour investiguer ces deux canaux, basé sur un cadre à la Grossman et Helpman (1994), dans lequel le lobbying est une stratégie à la disposition des ...

The energy considered as waste heat in industrial furnaces owing to inefficiencies represents a substantial opportunity for recovery by means of thermal energy storage (TES) implementation. Although conventional systems based on sensible heat are used extensively, these systems involve technical limitations. Latent heat storage based on phase change materials (PCMs) results in a promising alternative for storing and recovering waste heat. Within this scope, the proposed PCM-TES allows for demonstrating its implementation feasibility in energy-intensive industries at high temperature range. The stored energy is meant to preheat the air temperature entering the furnace by using a PCM whose melting point is 885 °C. In this sense, a heat transfer model simulation is established to determine an appropriate design based on mass and energy conservation equations. The thermal performance is analysed for the melting and solidification processes, the phase transition and its influence on heat transference. Moreover, the temperature profile is illustrated for the PCM and combustion air stream. The obtained results prove the achievability of very high temperature levels (from 700 to 865 °C) in the combustion air preheating in a ceramic furnace; so corroborating an energy and environmental efficiency enhancement, compared to the initial condition presenting an air outlet at 650 °C.

At the 1972 Stockholm Conference, participating States expressed concern about the extent and consequences of air pollution, laying the groundwork for international legal cooperation to address it. The Action Plan for the Human Environment included the need to promote scientific observation of the atmosphere, and the principles set out in the Stockholm Declaration served, as in other areas of environmental international law, to articulate the response to the threats identified. Since that meeting, the evolution of international legal protection of the atmosphere has been marked by the implementation of three international regimes. The European regime on transboundary air pollution, inaugurated in 1979, was the first model of international cooperation in this field, and influenced subsequent developments in the regimes on ozone layer protection and climate change. Taking into account the foundational impetus that the Stockholm Conference provided for the development of these regimes, this paper analyses the evolution of international legal protection of the atmosphere in the fifty years since the Conference was held

We present the architecture and design of the IANOS scheduling framework. The goal of the new Grid scheduling system is to provide a general job submission framework allowing optimal positioning and scheduling of HPCN applications. The scheduling algorithms used to calculate best-suited resources are based on an objective cost function that exploits information on the parameterization of applications and resources. This standard-based, interoperable scheduling framework comprises four general web services and three modules. The middleware is complemented with one client and one admin console. The implementation is based on proposed Grid and Web services standards (WSRF, WS-Agreement, JSDL, and GLUE). It is agnostic to a specific Grid middleware. The beta version of IANOS has been tested and integrated with UNICORE. The validation of IANOS is in progress by running different types of HPCN applications on a large-scale Grid testbed.

If femoral blood is not available at autopsy, toxicological analyses, in particular blood ethanol measurements, are carried out on cardiac blood. This is known to be subject to major redistribution. We aimed to determine whether subclavian blood can be equated with a peripheral blood sample and could be used if femoral blood is not available. The study was based on 50 medicolegal autopsies in which we compared ethanol concentrations between subclavian blood, the different heart blood compartments (right and left cardiac blood), and femoral blood. Mechanisms that could lead to variations in concentration, i.e., postmortem redistribution and/or endogenous production, were also taken into account in interpreting the results. Ethanol concentrations were determined by headspace gas chromatography with a flame ionization detector. In each case, we recorded the circumstances of death, resuscitation attempts if any, degree of putrefaction, chest or abdominal trauma, and/or inhalation of gastric fluid in the airways. Ethanol concentrations in subclavian blood were found to be close to those in peripheral blood (p = 0.948) and were not influenced by the degree of putrefaction (r = 0.017, p = 0.904), gastric ethanol concentration (r = -0.011, p = 0.940), inhalation of gastric contents in the airways (p = 0.461), or cardiac resuscitation attempts (p = 0.368). We discuss the possible explanations for these findings and stress the value of sampling subclavian blood when femoral blood is not obtainable at autopsy.

Inter-turn winding faults in five-phase ferrite-permanent magnet-assisted synchronous reluctance motors (fPMa-SynRMs) can lead to catastrophic consequences if not detected in a timely manner, since they can quickly progress into more severe short-circuit faults, such as coil-to-coil, phase-to-ground or phase-to-phase faults. This paper analyzes the feasibility of detecting such harmful faults in their early stage, with only one short-circuited turn, since there is a lack of works related to this topic in multi-phase fPMa-SynRMs. Two methods are tested for this purpose, the analysis of the spectral content of the zero-sequence voltage component (ZSVC) and the analysis of the stator current spectra, also known as motor current signature analysis (MCSA), which is a well-known fault diagnosis method. This paper compares the performance and sensitivity of both methods under different operating conditions. It is proven that inter-turn faults can be detected in the early stage, with the ZSVC providing more sensitivity than the MCSA method. It is also proven that the working conditions have little effect on the sensitivity of both methods. To conclude, this paper proposes two inter-turn fault indicators and the threshold values to detect such faults in the early stage, which are calculated from the spectral information of the ZSVC and the line currents.