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Il volume contiene gli abstract dei lavori accettati per i contributi orali e i poster presentati a HYPOTHESIS XII

Castor (Ricinus communis L.) is an oilseed species, which in southern Italy is cultivated as annual during the spring-summer period under irrigation, but in most temperate areas such as those of eastern coast of Sicily, it could be grown as semiperennial with no irrigation, by the adoption of autumnal sowings. A field experiment was conducted in southeastern Sicily with the aim of assessing plant surviving, seed yield and oil quality of four castor genotypes originating from different geographical areas (two Sicilian, one Tunisian and one Brazilian). The favorable climatic conditions allowed the plant to survive during the fall-winter period. Seed yield reached 3.45 t ha-1 on average of the two years and seed oil content ranged from 45% (Tunisian cultivar) to 48% ('Local RG 2' Sicilian genotype). Oil yield reflected the variation in seed yield. Genetic diversity for fatty acid composition and saponification number, iodine value and cetane number was evidenced. When ricinoleic acid is not taken into account, the oil of all genotypes satisfied the E.U. standards for biodiesel. The ricinoleic acid was the lowest (79%) in the Sicilian 'Local RG 2' and the highest (89%) in the Tunisian one, revealing a greater suitability of oil of the first genotype for biodiesel. In turn, the oil of Tunisian genotype could be exploited in other bio-based industrial sectors. The study also demonstrated that in the southeastern coast of Sicily autumnal sowings might be advantageous for castor grown as semi-perennial crop, mainly since they allow saving irrigation water.

Emergency building, devoted to give rapid and effective housing solutions to catastrophic and unexpected events, relies on the basic principles of construction rapidity and reversibility as well as the use of alternative energy sources. The growing need for environmental impact reduction in the building sector represents for temporary housing - especially under emergency conditions - a priority requisite, since, after given time lapses, areas occupied with emergency settlements will have to be recovered to their original use. In this case, the buildings' service life does not correspond to the life cycle of their materials and components; as a consequence, design activities will have to assure the dismantability and reusability of structures for further service cycles, making the whole process reversible: from construction to 'zero waste' de-construction. This paper aims at defining design criteria for low-impact emergency dwellings, assessing at the same time their applicability to corrugated steel pipes, obtained by assembling galvanized curved sheets - commonly used for underpasses and conduits - for which different use possibilities have been investigated. In this view, the research program has led to the definition of modular dwelling solutions. Then, technical feasibility studies have been carried out in collaboration with the industrial sector, taking advantage of consolidated production lines for innovative use purposes. Along the different research stages, a methodology has been defined for the assessment of the fundamental sustainability criteria through different simulation procedures; among these, the evaluation of the life-cycle environmental impacts with SimaPRO software and the 3D modelling for the maximization of the construction/environment integration - also in relation to the use of PV modules - have produced interesting results.

M.J.M. acknowledges funding from FCT through the grant SFRH/BPD/115566/2016. ALTALUZ (Reference PTDC/CTM-ENE/5125/2014). The optical properties of localized surface plasmon resonances (LSPR) sustained by self-assembled silver nanoparticles are of great interest for enhancing light trapping in thin film photovoltaics. First, we report on a systematic investigation of the structural and the optical properties of silver nanostructures fabricated by a solid-state dewetting process on various substrates. Our study allows to identify fabrication conditions in which circular, uniformly spaced nanoparticles are obtainable. The optimized NPs are then integrated into plasmonic back reflector (PBR) structures. Second, we demonstrate a novel procedure, involving a combination of opto-electronic spectroscopic techniques, allowing for the quantification of useful and parasitic absorption in thin photovoltaic absorber deposited on top of the PBR. We achieve a significant broadband useful absorption enhancement of 90% for 0.9 µm thick μc-Si:H film and demonstrate that optical losses due to plasmonic scattering are insignificant below 730 nm. Finally, we present a successful implementation of a plasmonic light trapping scheme in a thin film a-Si:H solar cell. The quantum efficiency spectra of the devices show a pronounced broadband enhancement resulting in remarkably high short circuit current densities (Jsc). preprint published

Decentralized detection in a network of wireless sensor nodes involves the fusion of information about a phenomenon of interest (PoI) from geographically dispersed nodes. In this paper, we investigate the problem of binary decentralized detection in a dense and randomly deployed wireless sensor network (WSN), whereby the communication channels between the nodes and the fusion center are bandwidth-constrained. We consider a scenario in which sensor observations, conditioned on the alternate hypothesis, are independent but not identically distributed across the sensor nodes.We compare two different fusion architectures, namely, the parallel fusion architecture (PFA) and the cooperative fusion architecture (CFA), for such bandwidthconstrained WSNs, where each sensor node is restricted to send a 1-bit information to the fusion center. For each architecture, we derive expression for the probability of decision error at the fusion center. We propose a consensus flooding protocol for CFA and analyze its average energy consumption. We analyze the effects of PoI intensity, realistic link models, consensus flooding protocol, and network connectivity on the system reliability and average energy consumption for both fusion architectures. We demonstrate that a trade-off exists among spatial diversity gain, average energy consumption, delivery ratio of the consensus flooding protocol, network connectivity, node density, and PoI intensity in CFA. We then provide insight into the design of cooperative WSNs.

Analysis of interdependencies in Electric Power Systems (EPS) has been recognized as a crucial and challenging issue to improve their trustworthiness. The recent liberalization process in energy markets has promoted the entry of a variety of operators in the electricity industry. The resulting new organization contributed to increase in complexity, heterogeneity and interconnection. This paper proposes a framework for analyzing EPS organized as a set of interconnected regions, both from the point of view of the electric power grid and of the cyber control infrastructure. The emphasis is on interdependencies and in assessing their impact on indicators representative of the QoS perceived by users. Taking a reference power grid as test case, the effects of failures on selected measures are shown, both in case the grid is partitioned in a number of regions and in case of a single region, to illustrate the behavior of different grid and control configurations.

Wood biomass is turned into industrial fuel through chipping. The efficiency of chipping depends on many factors, including chipper knife wear. Chipper knife wear was determined through a long-term follow-up study, conducted at a waste wood recycling yard. Knife wear determined a sharp drop of productivity (>20%) and a severe decay in product quality. Dry sharpening with a grinder mitigated this effect, but it could not replace proper wet sharpening. Increasing the frequency of wet sharpening sessions determined a moderate increase of knife depreciation cost, but it could drastically enhance machine performance and reduce biomass processing cost. Since benefits largely exceed costs, increasing the frequency of wet sharpening sessions may be an effective measure for reducing overall chipping cost. If the main goal of a chipper operator is to increase productivity and/or decrease fuel consumption, then managing knife wear should be a primary target. (C) 2014 Elsevier Ltd. All rights reserved.

Alternative fuels and energy vectors are becoming increasingly important in terms of technical, geopolitical, economic, and environmental aspects. In particular, gaseous fuels and vectors, such as fossil or synthetic natural gas (NG) blended with hydrogen, commonly help provide optimal strategies to reduce global and toxic emissions of internal combustion engines, owing to their adaptability, anti-knock capacity, lower toxicity of pollutants, reduced CO2 emissions, and costeffectiveness. However, diesel engines still represent the reference category among internal combustion engines in terms of maximum thermodynamic efficiency. The possibility offered by dual-fuel (DF) systems to combine the efficiency and performance of diesel engines with the environmental advantages of gaseous fuels has been the subject of extensive investigations. However, the simple replacement of diesel fuel with gaseous fuel does not allow for optimising the engine performance, owing to the high percentage of unburned gaseous fuel, which compromises the potential reduction of CO2; therefore, more complex combustion strategies should be realised. In this study, with the aim of improving the DF combustion process, an experimental investigation was performed to analyse low-temperature combustion (LTC), using NG and two enriched hydrogen-compressed NG blends as primary fuels. The LTC mode was activated by means of a very early advanced pilot injection and carried out in two close steps. The double pilot injection was used to control the energy release rate in the first combustion stage, thereby minimizing the increase of the rate of pressure and allowing the extension of the operation range under LTC. The experimental activity was also focused on analysing the particle emissions, as it is well known that these emissions, together with those of nitrogen oxide, constitute the main pollutants resulting from diesel fuel combustion. The results demonstrated the potential to reduce the unburned fuel, NOx, and particle emissions simultaneously, while maintaining equivalent CO2 emissions to a diesel-only engine. Both the timing and pressure of the pilot injection proved to be critical parameters for optimising the emissions and performance

The aeroelastic behavior of a flexible plate subjected to a uniform axial flow is investigated in the presence of a rigid plane set parallel to the plate. It is shown that the ground effect reduces the flutter inflow velocity and strengthens the possibility of using the flag for extracting energy from winds and currents. The numerical analysis is carried out assuming that both the unsteady potential incompressible flow and the plate can be described with 2D models, i.e., a lumped vortex panel method and a nonlinear Euler-Bernoulli beam model, respectively, without losing the essential features of the fluid-structure interaction. Asymmetry of post-critical behavior (limit-cycle oscillations) and sensitivity of the results to the main flag parameters (distance from the ground, mass ratio and damping) are also considered, including also the energy distribution over the identified proper orthogonal modes. The investigated reduction of the flutter velocity in ground effect has been also confirmed with experimental tests relative to a polypropylene flag with and without the rigid panel mimicking the presence of the ground.