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Measuring the social responsibility of European companies: a goal programming approach

  • García-Martínez, Gabriel|||0000-0002-4717-5890
  • Guijarro, Francisco|||0000-0002-8803-5165
  • Poyatos-León, Juan Ángel
[EN] Corporate social responsibility (CSR) can be measured by a number of different criteria, some of which are similar to each other, while others can be manifestly contrary to the general tendency. This means that some companies can obtain a good valuation in some criteria but a bad valuation in others, which makes it difficult to assess the company¿s overall CSR valuation. It is not easy to find a single measure that covers all aspects of corporate social performance. This paper aims to estimate multicriteria CSR performance through different models of goal programming and by taking into account all the dimensions that make up CSR. An illustrative example shows the result of applying these models to a database composed of 212 European companies, which enabled us to identify the most socially responsible group, regardless of the approach considered in the construction of the multicriteria performance. The results show that environmental and corporate governance dimensions are the most important elements in measuring this performance
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Numerical simulation and laboratory measurements on the influence of fractal dimension on the acoustic beam modulation of a Polyadic Cantor Fractal lenses

  • Tarrazó-Serrano, Daniel|||0000-0001-9986-0884
  • Castiñeira Ibáñez, Sergio|||0000-0001-6414-3906
  • Candelas Valiente, Pilar|||0000-0002-9924-7673
  • Fuster Escuder, José Miguel|||0000-0001-7778-8834
  • Rubio Michavila, Constanza|||0000-0002-4395-7473
[EN] The possibility of modulating the ultrasound beam produced by a transducer through lenses has become an important task. The fact that these lenses are flat, facilitates their design, construction and applications. If, in addition, the design itself incorporates geometries that affect differently the foci profile on the axial axis of the lens, improvements become more significant. In this work the design of a flat lens based on a Polyadic Cantor fractal geometries is presented. The influence of the so-called fractal dimension on the modulation of the ultrasonic beam to obtain the foci is analysed. In this paper, experimental results under controlled conditions are presented. The numerical solutions obtained have been validated., Investigation supported by the Ministry of Economy, Industry and Competitiveness, and the European Regional Development Fund TEC2015-70939-R (MINECO/FEDER).
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Manipulation of focal patterns in acoustic Soret type zone plate lens by using reference radius/phase effect

  • Tarrazó-Serrano, Daniel|||0000-0001-9986-0884
  • Rubio Michavila, Constanza|||0000-0002-4395-7473
  • Minin, Oleg V.
  • Candelas Valiente, Pilar|||0000-0002-9924-7673
  • Minin, Igor V.
[EN] The manipulation of focal patterns of acoustic underwater Soret Zone Plate lens in far fields, such as manipulation (optimization) of Sidelobe Level and the design of long depth of focus by selecting the simple free parameter called reference radius (phase) has been demonstrated. Two effects have been studied by means of numerical simulations. Regarding the first effect, simulations demonstrate diffraction limited focal spot (0.47 wavelength) and 3 dB reduction of the first Side Lobe Level using Soret ZP with an optimal reference radius and without causing neither main lobe broadening or gain reduction. In the second effect, by using numerical simulations an increasing of depth of focus, more than 2 times, in comparison with classical Soret ZP with high numerical aperture (F/D=2.5), was observed., This work has been supported by TEC2015-70939-R (MINECO/FEDER).
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Tunable depth of focus of acoustical pupil masked Soret Zone Plate

  • Castiñeira Ibáñez, Sergio|||0000-0001-6414-3906
  • Tarrazó-Serrano, Daniel|||0000-0001-9986-0884
  • Minin, Oleg V.
  • Rubio Michavila, Constanza|||0000-0002-4395-7473
  • Minin, Igor V.
[EN] In acoustical lenses both resolution and depth of focus are determined by diffraction and the smaller the lens aperture the worse the resolution and the greater the depth of focus. Diffraction-limited resolution has a Soret Zone Plate, but a long depth of focus has an axicon. Nevertheless, these are two different devices each of which requires its own independent design. In this paper, we have shown that the transition from focusing to a diffraction limited spot to a quasi-diffraction free beam can be realized in the same focusing device without changing its topology. It has been shown that using a classical planar Soret Zone Plate lens made of a concentric array of circular aperiodical rings with an amplitude pupil mask placed closely to the surface of lens allows to form a quasi-Bessel beams under specific conditions, part of a diffracted wave collimates, producing an elongated focus. Experiments are performed in water tanks in order to verify the simulation results. Experimental verification shown that the depth of focus of a pupil-masked Soret Zone Plate increases 1.63 times and resolution increases 1.2 times (with minimal beam waist about of 0.67 of wavelength and depth of focus about 5.72 of wavelength). By dynamically controlling the size of the amplitude pupil mask, it is possible to quickly control the depth of focus of an acoustic lens., This work has been supported by Spanish MINECO (TEC2015-70939-R) and was partially supported by Tomsk Polytechnic University Competitiveness Enhancement Program.
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Enhancement of pupil-masked wavelength-scale gas-filled flat acoustic lens based on anomaly apodization effect

  • Rubio Michavila, Constanza|||0000-0002-4395-7473
  • Tarrazó-Serrano, Daniel|||0000-0001-9986-0884
  • Minin, Oleg V.
  • Uris Martínez, Antonio
  • Minin, Igor V.
[EN] In this letter, the improvement in focus by the use of a pupil mask produced in an acoustic mesoscale cuboid particle ¿lled with CO2 is reported. Thereby, the result shows that the pupil mask increases the sound intensity and also increases the resolution (or a reduction of the full width at half maximum, FWHM) in focus compared to the non-masked one. These results are important because they con¿rm the effect of abnormal amplitude apodization for a one-wavelength dimension acoustic lens and demonstrate that it is possible to improve sound focusing of a cuboid gas-¿lled lens with one wavelength dimension. This is the smallest size of an acoustic lens ever considered in this type of literature, with side dimensions of the cube equal to one wavelength and a diameter to focus ratio of 2.5, the sound ampli¿cation in focus is 5.4 dB at 4125 Hz, with the resolution near to the diffraction limit., This work has been supported by TEC2015-70939-R (MINECO/FEDER). The research was partially supported by Tomsk Polytechnic University Competitiveness Enhancement Program.
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Cathodic protection of steel guitar strings against the corrosive effect of human sweat

  • Bonastre Cano, José Antonio|||0000-0002-5068-6608
  • López-Muelas, José Luis
  • Segura Alcaraz, Jorge Gabriel|||0000-0001-8296-3609
  • Gadea Borrell, José Mª|||0000-0003-0740-8781
  • Juliá Sanchis, Ernesto|||0000-0003-2940-3906
  • Cases, Francisco|||0000-0001-8105-4489
[EN] The steel strings of guitars suffer aggressive corrosion when exposed to human sweat. To mitigate this effect, in this research work guitar strings were subjected to cathodic protection by impressed current. To evaluate the corrosion, electrochemical techniques were used to determine the polarization resistance and the instantaneous corrosion rate, as well as the weight loss by gravimetric measurements. Microphotographs were also carried out to compare the corrosion status of the steel strings by stereoscopic optical and field emission scanning electron microscopy. Impressed current cathodic protection allowed the formation of iron oxides on steel guitar strings to be reduced by around 40%, Authors wish to thank to Spanish Agencia Estatal de Investigación de Economía(AEI) and European Union (FEDER funds) for the financial support (contract MAT2016-77742-C2-1-P).
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Restoration prioritization framework for roadway high cut slopes to reverse land degradation and fragmentation

  • Canto-Perello, Julian|||0000-0002-0076-6570
  • Morera Escrich, Jose Luis
  • Martín Utrillas, Manuel Guzmán
  • Curiel-Esparza, Jorge|||0000-0002-2453-5822
[EN] Land degradation is one of the most critical global environmental threats. The EU Biodiversity Strategy to 2020 has appointed land degradation and ecosystems fragmentation caused by transport infrastructures as crucial threats to biodiversity. Implementing environmental criteria in roadway project conception phase for restoring large cut slopes will prevent this threat. There is a lack of decision support systems to implement environmental criteria in the decision making procedure to restore high cut slopes. The major difficulties have been building consensus and ensuring traceability and transparency from the panel of experts. This paper presents a hybrid framework capable of dealing with environmental criteria and also with conventional territorial and economic criteria. The decision support procedure combines the Analytical Hierarchy Process with the Delphi technique and the VIKOR procedure. The experts' consensual decision-making process is properly documented, unambiguous and verifiable. The results of this study yielded that the functional and environmental criteria are the key factors in the decision-making process of large cut slope restoration projects. And it has been found the suitability of the cut-and-cover tunnels despite their higher cost and complexity of its construction.
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Collaborative elicitation to select a sustainable biogas desulfurization technique for landfills

  • Curiel-Esparza, Jorge|||0000-0002-2453-5822
  • Reyes-Medina, Manuel
  • Martín Utrillas, Manuel Guzmán
  • Martínez-García, María Peña
  • Canto-Perello, Julian|||0000-0002-0076-6570
[EN] The 2015 Paris Agreement within the United Nations Framework Convention on Climate Change establishes three key ways for the reduction of the emissions of Greenhouse Effect Gases: mitigation, adaptation and resilience of ecosystems. In this context, one of the major goals for methane recovery from waste is the process of obtaining biogas from biomass or waste, a form of fuel with zero impact on the carbon footprint of the planet. All possible uses of biogas depend mainly on the degree of purification obtained. The removal of hydrogen sulfide (H2S) is the main weakness in using biogas in industrial applications. If the use of biogas is intended for engines, turbines or to enrich the biogas to obtain natural gas, lowering the levels of H2S will be necessary, in order to avoid corrosion in gas lines and in engines. Biogas desulfurization can be achieved through different techniques: physical, chemical, biological or hybrid procedures. Selecting the most sustainable technique to clean biogas entails a complex problem, which involves the analysis of these desulfurization treatments under different criteria. In this paper, we present a novel collaborative elicitation to select the consensus procedure for the reduction of the concentration of H2S in biogases from landfills. The elicitation technique is based on fuzzy set theory and VIKOR method in order to handle intangible data and to avoid potential bias by the panelists. The proposed hybrid method guarantees traceability and transparency to achieve consensus among the panel of experts during the decision making procedure.
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Effects of dietary barley on rainbow trout exposed to an acute stress challenge

  • Pinedo-Gil, Julia
  • Martín-Diana, Ana Belén
  • Bertotto, D.
  • Sanz-Calvo, M.A.
  • Jover Cerda, Miguel
  • Tomas-Vidal, A.|||0000-0002-2985-9324
[EN] The present study evaluates the effect of dietary barley, based on its potential stress-relieving properties, on rainbow trout under acute stress challenge (hypoxia and crowding) and their recovery. Diets were formulated containing increasing barley concentrations (0, 4, 8, 16, 32%). Cortisol on plasma and fin, glucose and lactate plasma levels and malondialdehyde (MDA) in muscle were determined under normoxia before the stress test (basal levels), 30 min after the acute stress challenge and also during normoxia recovery (6 and 12 h after the stress). Results showed that at basal levels the inclusion of barley had no influence on cortisol, glucose nor on lactate values. After 30 min from the stress challenge, there was a significant increase in cortisol, glucose and lactate concentration in fish of all groups. Plasma cortisol showed the lowest levels in fish fed with diets at a medium (8%) of barley concentration and returned to basal levels 6 h after the stress stimulus with no differences between diets. Glucose values showed a less clear tendency 30 min after the stress challenge with lower levels in the control group, fish fed with 8% and 32% of barley in the diets and returned to basal levels in almost all the groups only 12 h after the stress challenge. Lactate showed the same trend as with glucose after the stress challenge but it returned to basal levels in 6 h. Interestingly, there was a significant decrease of lipid oxidation (MDA) in muscle soon after the stress test of fish fed with the highest barley levels. The present results suggest a potential positive effect of dietary barley on trout stress response., This work has been co-funded with FEDER and INIA funds. Julia Pinedo has been granted with the FPI-INIA grant number 21 (call 2012, BOE-2012-13337).
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The impact of adaptive forest management on water fluxes and growth dynamics in a water-limited low-biomass oak coppice

  • Campo García, Antonio Dámaso Del
  • González Sanchís, María del Carmen
  • Garcia-Prats, Alberto|||0000-0001-5605-8349
  • Ceacero Ruiz, Carlos J.
  • Lull, Cristina|||0000-0001-9270-2365
[EN] Marginal semi-arid forests in areas currently affected by climate change are a challenge to forest management, which has to focus on key functional traits that can effectively contribute to resistance under extreme drought. We studied the effects of thinning in a marginal forest by quantifying functional responses relating to growth, carbon and water fluxes. Two experimental plots were established, one thinned in 2012 and the other one left as a control. The environmental conditions varied substantially during the 4-year study period, although dry years predominated. There were signs of dieback in the control with a decreasing inter-annual trend in LAI, as opposed to the treated plots, where LAI by the end of the study almost reached pre-thinning levels. Sap flow and transpiration were greatly enhanced by the treatment, with thinned trees transpiring 22.41 tree(-1) day(-1) in the growing season, about twice the control figures. The seasonal patterns of transpiration and soil moisture were uncoupled, indicating a contribution of deep groundwater to the former flux. In the control, limitations to water and carbon dynamics (canopy conductance) occurred at soil moisture values below 16%, whereas in the thinned trees these limitations appeared when soil moisture dropped below 10%. Overall, oaks' transpiration was enhanced with thinning to the point that stand-water use surpassed that of the control by the second half of the study period, averaging 24% of gross rainfall in both plots. Soil evaporation increased from 12 to 20% of gross rainfall after treatment in the overall period. The treatment had a profound watering effect in this marginal forest, led by fewer trees using the same amount of water as those in the untreated overstocked plot. This research may provide guidelines for ecohydrology-oriented silviculture in stands experiencing tree encroachment and transformation into shrublands that are more prone to global change-induced disturbances., This study is a component of the research projects HYDROSIL (CGL2011-28776-C02-02), SILWAMED (CGL2014-58127-C3-2) and CEHYRFO-MED (CGL2017-86839-C3-2-R), funded by the Spanish Ministry of Science and Innovation and the FEDER fund of the EU. The authors are grateful to the Valencia Regional Government (CMAAUV, Generalitat Valenciana) and ACCIONA for their support in allowing the use of the experimental forest La Hunde and for their assistance in the fieldwork.
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