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Doubly-fed induction generators (DFIGs) are widely used in wind turbine systems. Traditionally, they rely on the grid voltage to operate. However, the increasing penetration of renewables necessitates wind turbines that can contribute to grid stability, and grid-forming control (GFM) has emerged as an attractive solution. Traditionally, the GFM control of DFIGs has been proposed as a single-loop control of the rotor flux magnitude and orientation, while double-loop schemes based on virtual impedance or virtual admittance have been scarcely investigated. This paper analyzes the operation and small-signal stability of a virtual-impedance-based dual-loop GFM control for DFIG. The small-signal impedance-model is derived and used to analyze the system stability in case of strong and weak grid connection. Electromagnetic transient simulations on a 1.5 MW wind turbine system are presented to validate the analysis.

Doubly-fed induction generators (DFIGs) are widely used in wind turbine systems. Traditionally, they rely on the grid voltage to operate. However, the increasing penetration of renewables necessitates wind turbines that can contribute to grid stability, and grid-forming control (GFM) has emerged as an attractive solution. Traditionally, the GFM control of DFIGs has been proposed as a single-loop control of the rotor flux magnitude and orientation, while double-loop schemes based on virtual impedance or virtual admittance have been scarcely investigated. This paper analyzes the operation and small-signal stability of a virtual-impedance-based dual-loop GFM control for DFIG. The small-signal impedance-model is derived and used to analyze the system stability in case of strong and weak grid connection. Electromagnetic transient simulations on a 1.5 MW wind turbine system are presented to validate the analysis.

Thermokinetics of Biochar production.

Thermokinetics of Biochar production.

Treball final de Grau en Psicologia. Codi: PS1048. Curs acadèmic 2015-2016 El estresante estilo de vida de la sociedad actual junto con la mala concepción sobre las posibles consecuencias del consumo de alcohol podrían ser algunas de las causas de que actualmente el alcohol sea una de las drogas más consumidas a nivel mundial según la OMS. Sin embargo, a pesar de todos los avances de la neurociencia, el mecanismo exacto de cómo actúa el alcohol en el SNC nos es aún desconocido. El objetivo de este trabajo es tratar de plantear y dar pruebas a favor de una hipótesis sobre como podría actuar realmente el alcohol en el cerebro. El método de este trabajo consta del análisis de 4 estudios que muestran las manipulaciones de diferentes mediadores de calcio y AMPc-­‐PKA y las consecuencias de esas manipulaciones a nivel molecular, celular, neurobiológico y conductual. Por una parte los resultados obtenidos nos muestran que posiblemente, estos mediadores de calcio tengan una función muy importantes a la hora de explicar el mecanismo de acción del alcohol en el cerebro. Pero, no obstante, no son suficientes evidencias como para afirmar con completa claridad y certeza que este sea el mecanismo exacto de actuación del alcohol en el SNC. The stressfull way of life of our nowadays society in adition to the missconception of the potencial consequences from alcohol consum could be some of the reasons for why alcohol is the worldwide most consumed drug according to OMS. However, besides all the neuroscience developments, the true mechanism of alcohol functionament on the SNC has been not proved. The method of this paper consists of the analysis of 4 studies that show the manipulations of the different mediators of calcium and cAMP-­‐PKA and the consequences of these manipulations at a molecular, cellular, neurobiological and behavioural level. The results, in one hand, show that is possible that those mediators of calcium are important for understands the true mechanism of how alcohol works in the brain. However, there are no enough evidences to completely agree that this is the exact mechanism by which alcohol acts at a central level.

Treball final de Grau en Psicologia. Codi: PS1048. Curs acadèmic 2015-2016 El estresante estilo de vida de la sociedad actual junto con la mala concepción sobre las posibles consecuencias del consumo de alcohol podrían ser algunas de las causas de que actualmente el alcohol sea una de las drogas más consumidas a nivel mundial según la OMS. Sin embargo, a pesar de todos los avances de la neurociencia, el mecanismo exacto de cómo actúa el alcohol en el SNC nos es aún desconocido. El objetivo de este trabajo es tratar de plantear y dar pruebas a favor de una hipótesis sobre como podría actuar realmente el alcohol en el cerebro. El método de este trabajo consta del análisis de 4 estudios que muestran las manipulaciones de diferentes mediadores de calcio y AMPc-­‐PKA y las consecuencias de esas manipulaciones a nivel molecular, celular, neurobiológico y conductual. Por una parte los resultados obtenidos nos muestran que posiblemente, estos mediadores de calcio tengan una función muy importantes a la hora de explicar el mecanismo de acción del alcohol en el cerebro. Pero, no obstante, no son suficientes evidencias como para afirmar con completa claridad y certeza que este sea el mecanismo exacto de actuación del alcohol en el SNC. The stressfull way of life of our nowadays society in adition to the missconception of the potencial consequences from alcohol consum could be some of the reasons for why alcohol is the worldwide most consumed drug according to OMS. However, besides all the neuroscience developments, the true mechanism of alcohol functionament on the SNC has been not proved. The method of this paper consists of the analysis of 4 studies that show the manipulations of the different mediators of calcium and cAMP-­‐PKA and the consequences of these manipulations at a molecular, cellular, neurobiological and behavioural level. The results, in one hand, show that is possible that those mediators of calcium are important for understands the true mechanism of how alcohol works in the brain. However, there are no enough evidences to completely agree that this is the exact mechanism by which alcohol acts at a central level.

The aim of the joint activity between CNR ITAE and University of Malta, funded in the framework of a bilateral agreement is the preliminary study of the possible application of thermally-activated technologies for the refrigeration of fish on-board of fishing vessels, with particular attention to the Mediterranean area. In such a context, the two partners, given their expertise in the adsorption and absorption cooling technologies, dedicated the first year of the joint project on several activities needed to define possible integration solutions on-board. The following report is then organized as follows: - Section 3 reports an analysis of the state-of-the-art concerning existing refrigeration systems currently employed in the fishing vessels' application as well as innovative activities recently performed on the possible integration of thermally-driven technologies for the refrigeration. - Section 4 focuses on the definition of possible integration between the waste heat recovered from the engines of the fishing vessel and the sorption technology for refrigeration. This analysis takes into account different possible applications, in terms of refrigeration temperatures as well as capacities. Furthermore, different possible waste heat streams at different temperature levels are investigated. - Section 5 identifies the typical working boundary conditions under which the fishing vessel operates, in terms of cooling demand, also considering different climatic zones (i.e. different geographical areas in which the vessel operates) and vessels' typology. - Section 6 investigates possible working pairs, both for adsorption and absorption technologies, which are promising for the given boundary conditions in Section 5. This activity is needed to set the operational limits that each technology and working pair cannot overcome. - Section 7 reports the calculations performed for each working pair and operating conditions, both taking into account thermodynamic constraints as well as analysing literature results on different prototypes realized and tested. - Section 8 introduces a dynamic model, implemented in TRNSYS environment, of an absorption refrigerator, which was validated and will be used in the following activities to investigate the defined schematics in Section 4. - Section 9 defines the Key Performance Indicators (KPIs) that will be used in the following activities to compare the achievable results of the different configurations.

The aim of the joint activity between CNR ITAE and University of Malta, funded in the framework of a bilateral agreement is the preliminary study of the possible application of thermally-activated technologies for the refrigeration of fish on-board of fishing vessels, with particular attention to the Mediterranean area. In such a context, the two partners, given their expertise in the adsorption and absorption cooling technologies, dedicated the first year of the joint project on several activities needed to define possible integration solutions on-board. The following report is then organized as follows: - Section 3 reports an analysis of the state-of-the-art concerning existing refrigeration systems currently employed in the fishing vessels' application as well as innovative activities recently performed on the possible integration of thermally-driven technologies for the refrigeration. - Section 4 focuses on the definition of possible integration between the waste heat recovered from the engines of the fishing vessel and the sorption technology for refrigeration. This analysis takes into account different possible applications, in terms of refrigeration temperatures as well as capacities. Furthermore, different possible waste heat streams at different temperature levels are investigated. - Section 5 identifies the typical working boundary conditions under which the fishing vessel operates, in terms of cooling demand, also considering different climatic zones (i.e. different geographical areas in which the vessel operates) and vessels' typology. - Section 6 investigates possible working pairs, both for adsorption and absorption technologies, which are promising for the given boundary conditions in Section 5. This activity is needed to set the operational limits that each technology and working pair cannot overcome. - Section 7 reports the calculations performed for each working pair and operating conditions, both taking into account thermodynamic constraints as well as analysing literature results on different prototypes realized and tested. - Section 8 introduces a dynamic model, implemented in TRNSYS environment, of an absorption refrigerator, which was validated and will be used in the following activities to investigate the defined schematics in Section 4. - Section 9 defines the Key Performance Indicators (KPIs) that will be used in the following activities to compare the achievable results of the different configurations.

Abstract This paper focuses on the study of an electricity market model, which evolves in T+1 stages, so that, at each stage, a continuum state of nature is possible. The decision-making framework of large consumers is considered: agents consume, they have the opportunity to produce, and the capability of signing contracts. Uncertainty on future possible stages leads to the problem being located in a filtered probability space. The aim is to reformulate the problem as a stochastic quasi-variational inequality, in order to obtain an existence result of equilibrium solutions.