El futuro de la estructura bancaria en Castellón

Material addicional de la ponència presentada al III Congrés Obert i Virtual Castelló 2020. Castelló de la Plana, 2011-201

The ENSO signature in sea-surface temperature in the Gulf of California

We analyzed 21 years of sea-surface temperature satellite images to explore the spatial signature of the El Niño-Southern Oscillation signal in the Gulf of California. We used empirical orthogonal function analysis to extract the principal mode of the nonseasonal sea-surface temperature variability and compared it to the spatial signature of the Southern Oscillation Index. The first mode accounted for 80% of nonseasonal variability and its amplitude time series was significantly correlated to the Southern Oscillation Index (r = −0.58,P \u3c 0.01). The amplitude of this mode and its statistical relation to the El Niño is stronger during winter, which suggests that forcing of sea-surface temperature variability occurs through the disruption of the wind-driven upwelling corridor along the eastern coast due to El Niño-related atmospheric teleconnections. We also examined weekly time series of coastal sea-surface temperature coastal anomalies along the coast of North America, including the interior of the Gulf of California, during the strong 1997–98 El Niño. We found a poleward propagating signal that reached the mouth of the Gulf of California at the end of spring and continued its poleward propagation along the west coast of the peninsula slightly delayed; it also resulted in warming inside the Gulf of California. This observation may provide an explanation for the variable extension of the El Niño signature along the Pacific coast of North America

The Miralles poetic drawing experiments and creates

[EN] To understand the architecture of Enric Miralles it is necessary to understand how he drew it, it was his design process that defined his architecture and drawing, the main instrument in this creative evolution. His drawing was always intentional and it was his main tool. Draw, draw and draw again, this was his main method. His strategies focused on a work process that distances itself from the resources used in a certain current architecture world. The drawing was the instrument of dialogue, capable of selecting the lines that would define and transform all the conditions and concerns, into a concrete architectural reality. By way of synthesis, we will say that he used on numerous occasions in an indiscriminate way and with poetic intention, a spoken drawing, a representation drawing, an abstract drawing and a projection drawing.[ES] Para entender la arquitectura de Enric Miralles es necesario comprender como la dibujaba, era su proceso proyectual el que definía su arquitectura y el dibujo, el instrumento principal en este devenir creativo. Su dibujo era siempre de intención y fue su principal herramienta. Dibujar, dibujar y volver a dibujar, éste era su método principal. Sus estrategias se centraban en un proceso de trabajo que se distancia de los recursos utilizados en el mundo de cierta arquitectura actual. El dibujo era el instrumento de diálogo, capaz de seleccionar las líneas que definirían y transformarían todos los condicionantes e inquietudes, en una realidad arquitectónica concreta. A modo de síntesis diremos que utilizó en numerosas ocasiones de forma indiscriminada y con intención poética, un dibujo “hablado”, un dibujo de “representación”, un dibujo “abstracto” y un dibujo de “proyectación”.Giménez Mateu, L.; Gilabert Sanz, S.; Serra Lluch, JDR. (2022). El dibujo poeta de un Miralles que experimenta y crea. EGA Expresión Gráfica Arquitectónica. 27(46):264-283. https://doi.org/10.4995/ega.2022.18730264283274

Unavailability model for demand-caused failures of safety components addressing degradation by demand-induced stress, maintenance effectiveness and test efficiency

[EN] The reliability, availability and maintainability (RAM) modelling of safety equipment has long been a topic of major concern. Some RAM models have focused on explicitly addressing the effect of component degradation and surveillance and maintenance policies, searching for an optimum level of the safety component RAM by adjusting surveillance and maintenance related parameters. As regards the reliability contribution, these components normally have two main types of failure mode that contribute to the probability of failure on demand (PFD): (1) by demand-caused and (2) standby-related failures. The former is normally associated with a demand failure probability, which is affected by the degradation caused by demand-related stress. Surveillance testing therefore not only introduces a positive effect, but also an adverse one, which it compensates by performing maintenance activities to eliminate or reduce the accumulated degradation. This paper proposes a new model for the demand failure probability that explicitly addresses all aspects of the effect of demand-induced stress (mostly test-induced stress), maintenance effectiveness (PAS or PAR model) and test efficiency. A case study is included on an application to a typical motor-operated valve in a nuclear power plant.The authors are grateful to the Spanish Ministry of Science and Innovation for the financial support received (Research Projects ENE2013-45540-R and ENE2016-80401-R) and the doctoral scholarship awarded (BES-2014-067602). The study also received financial support from the Spanish Research Agency and the European Regional Development Fund.Martorell-Aygues, P.; Martón Lluch, I.; Sánchez Galdón, AI.; Martorell Alsina, SS. (2017). Unavailability model for demand-caused failures of safety components addressing degradation by demand-induced stress, maintenance effectiveness and test efficiency. Reliability Engineering & System Safety. 168:18-27. https://doi.org/10.1016/j.ress.2017.05.044S182716

Onshore wind farms maintenance optimization using a stochastic model

A specific feature of wind power generation is the stochastic behavior of wind velocity which determines the energy produced, and also influences the turbine degradation process due to the stochastic load suffered by the wind turbine. Thus, wind turbines present a degradation process more complex than the equipment that work under stationary conditions. The selection of a maintenance strategy, that comprises the date to perform a maintenance activity, the maintenance frequency and the duration of such activity have a great influence on the operational cost, that determines the plant viability. Wind velocity probability distribution can be obtained from daily wind data measurements, and by Monte Carlo sampling, it is possible to estimate the power generated. This generation has an associated cost due to the loss of production during maintenance. This work is focused on finding the best maintenance strategy that minimizes the total cost and maximizes the annual energy produced of a wind turbine considering the maintenance frequency as a decision variable. (C) 2012 Published by Elsevier LtdCarlos Alberola, S.; Sánchez Galdón, AI.; Martorell Alsina, SS.; Marton Lluch, I. (2013). Onshore wind farms maintenance optimization using a stochastic model. Mathematical and Computer Modelling. 57(7-8):1884-1890. doi:10.1016/j.mcm.2011.12.025S18841890577-

Endothelium-dependent relaxation of human saphenous veins in response to vasopressin and desmopressin

Purpose:The goal of this study was to determine the effects of vasopressin and the selective V2-receptor agonist desmopressin on human saphenous veins, with special emphasis on endothelium-mediated responses.Methods:Human saphenous vein segments were obtained from 35 patients undergoing coronary bypass surgery. Paired segments, one normal and the other deendothelized by gentle rubbing, were mounted for isometric recording of tension in organ baths. Concentration-response curves to vasopressin and desmopressin were determined in the presence and in the absence of either the V,-receptor antagonist d(CH2)5Tyr(Me)AVP (10−6 mol/L), the V1-V2 receptor antagonist desGly-d(CH2)5D-Tyr(Et)ValAVP (10−6 mol/L), indomethacin (10−6 mol/L), or NG-nitro-L-arginine methyl ester hydrochloride (L-NAME, 10−4 mol/L).Results:In vein rings under resting tension, vasopressin produced concentration-dependent, endothelium-independent contractions with a concentration of vasopressin producing-half-maximal contractions (EC50) of 3.44 × 10−8 mol/L. The vasopressin V1-receptor antagonist (10−6 mol/L) displaced the control curve to vasopressin 9.86-fold to the right in a parallel manner. In precontracted vein rings previously treated with the V1-antagonist (10−6 mol/L), vasopressin caused endothelium-dependent relaxations. This relaxation was reduced significantly by indomethacin (10−6 mol/L) and unaffected by the V1-V2-receptor antagonist (10−6 mol/L) or by L-NAME (10−4 mol/L). Desmopressin caused endothelium-dependent relaxations in precontracted vein rings that were inhibited by the mixed V1-V2-receptor antagonist and by indomethacin, but not by the V1-antagonist or by pretreatment with L-NAME.Conclusions:These observations indicate that vasopressin exerts contractile effects on human saphenous vein by V1-receptor stimulation. Vasopressin causes dilatation of human saphenous vein only if V1-receptor blockade is present. This relaxation appears to be mediated by the release of relaxant Prostaglandins, probably derived from endothelial cells, and is independent of V2-receptor stimulation or release of nitric oxide. Desmopressin elicits relaxation that is largely dependent on V2-receptor stimulation, which may bring about the release of dilating Prostaglandins from the endothelial cells

Parameter Estimation of a Reliability Model of Demand-Caused and Standby-Related Failures of Safety Components Exposed to Degradation by Demand Stress and Ageing That Undergo Imperfect Maintenance

[EN] One can find many reliability, availability, and maintainability (RAM) models proposed in the literature. However, such models become more complex day after day, as there is an attempt to capture equipment performance in a more realistic way, such as, explicitly addressing the effect of component ageing and degradation, surveillance activities, and corrective and preventive maintenance policies. Then, there is a need to fit the best model to real data by estimating the model parameters using an appropriate tool. This problem is not easy to solve in some cases since the number of parameters is large and the available data is scarce. This paper considers two main failure models commonly adopted to represent the probability of failure on demand (PFD) of safety equipment: (1) by demand-caused and (2) standby-related failures. It proposes a maximum likelihood estimation (MLE) approach for parameter estimation of a reliability model of demand-caused and standby-related failures of safety components exposed to degradation by demand stress and ageing that undergo imperfect maintenance. The case study considers real failure, test, and maintenance data for a typical motor-operated valve in a nuclear power plant. The results of the parameters estimation and the adoption of the best model are discussed.The authors are grateful to the Spanish Ministry of Science and Innovation for the financial support received (Research Project ENE2016-80401-R) and the doctoral scholarship awarded (BES-2014-067602). The study also received financial support from the Spanish Research Agency and the European Regional Development Fund.Martorell Alsina, SS.; Martorell-Aygues, P.; Sánchez Galdón, AI.; Mullor, R.; Martón Lluch, I. (2017). Parameter Estimation of a Reliability Model of Demand-Caused and Standby-Related Failures of Safety Components Exposed to Degradation by Demand Stress and Ageing That Undergo Imperfect Maintenance. Mathematical Problems in Engineering. (7042453):1-11. https://doi.org/10.1155/2017/7042453S111704245

Optimization of test and maintenance of ageing components consisting of multiple items and addressing effectiveness

[EN] There are many models in the literature that have been proposed in the last decades aimed at assessing the reliability, availability and maintainability (RAM) of safety equipment, many of them with a focus on their use to assess the risk level of a technological system or to search for appropriate design and/or surveillance and maintenance policies in order to assure that an optimum level of RAM of safety systems is kept during all the plant operational life. This paper proposes a new approach for RAM modelling that accounts for equipment ageing and maintenance and testing effectiveness of equipment consisting of multiple items in an integrated manner. This model is then used to perform the simultaneous optimization of testing and maintenance for ageing equipment consisting of multiple items. An example of application is provided, which considers a simplified High Pressure Injection System (HPIS) of a typical Power Water Reactor (PWR). Basically, this system consists of motor driven pumps (MDP) and motor operated valves (MOV), where both types of components consists of two items each. These components present different failure and cause modes and behaviours, and they also undertake complex test and maintenance activities depending on the item involved. The results of the example of application demonstrate that the optimization algorithm provide the best solutions when the optimization problem is formulated and solved considering full flexibility in the implementation of testing and maintenance activities taking part of such an integrated RAM model.Authors are grateful to the Spanish Ministry of Science and Innovation for the financial support of this work (research project ENE2013-45540-R) and the Doctoral fellow (BES-2011-043906 and BES-2014-067602).Martón Lluch, I.; Martorell Aigües, P.; Mullor, R.; Sánchez Galdón, AI.; Martorell Alsina, SS. (2016). Optimization of test and maintenance of ageing components consisting of multiple items and addressing effectiveness. Reliability Engineering and System Safety. 153:151-158. https://doi.org/10.1016/j.ress.2016.04.015S15115815