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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.

Cereals, staple crops in human nutrition, are called to face manifold challenges to encounter the urgent demand of food along with a higher nutritional value ensuring the sustainability of the supply chain. In this view, research focuses on two main topics; firstly, the rise in productivity, balancing the growing demand of food, consistent with the availability of environmental resources. The second issue regards the urgency to properly cover the nutritional needs of the population which has become more sensitive to pathologies related to high-calorie eating habits and poor in valuable nutritional compounds. Faced with such important issues, it is desirable to adopt a full approach, based on projects aimed at satisfying multiple requests at once. The research here discussed concerns the development of three durum wheat genotypes in which novel properties have been combined both in the health-functional profile of the derived foods and in the milling characteristics of the grain. The project involves a group of durum wheat genotypes, in which the starch component has been modified in the amount of amylose, a polysaccharide that, together with amylopectin, constitutes the reserve starch. The high amylose genotypes are of interest due to the low glycemic profile and the prebiotic functionality of the derived foods depending on the increase in "resistant starch"; the amylose-free genotype is suitable for the design of highly digestible foods ideal for specific uses, such as nutrition for infants. These genotypes were, therefore, the subject of a further improvement breeding program focused on modifying the hardness of the seed associated with the efficiency and sustainability of grinding and the quality of the final products. In detail, three different genotypes of durum wheat have been selected:1) Soft Svevo /Sv SSIIa and 2) Soft Svevo/Sv SBEIIa combine a high amylose content with a softer kernel that results in increased resistant starch content and energy saving during the milling process. The third genotype, Soft Svevo/Sv Waxy, combines a softer kernel with free amylose starch following a novel starch digestibility profile suited for specific food categories. A marker-assisted selection based on HRM-genotyping has been performed to identify the homozygous mutants in the progenies of the three different crosses. Biochemical analyses such as the determination of total starch, resistant starch, starch damage, ?-glucan and arabinoxylan content are in progress and will be able to highlight the potential value of the selected genotypes.

This paper deals with the medium between two reconfigurable sensor nodes characterized by radio interfaces that support multiple channels for exchanging real-time messages under energy constraints. These constraints are violated if the consumed energy in transmission is higher than the remaining quantity of energy. A reconfiguration, i.e., any addition or removal of tasks in devices and consequently of messages on the medium, can cause the violation of real-time or energy constraints at run time. To achieve a feasible scheduling in time (i.e., message deadlines will be respected) and energy (i.e., there is available energy) on the medium, we propose new dynamic solutions: Balance, Dilute, and a Combination of them to manage any addition or removal of messages. The proposed approach utilizes the energy harvesting techniques and the PowerControl algorithm to reduce the nonharvested consumed energy. The proposed strategies achieve significant improvement over existing methods and provide the highest percentage of adding messages, with a lower average in response time and energy consumption. They reach a percentage of success in adding the highest priority messages while meeting deadlines up to 85%.

The potential for global forest cover The restoration of forested land at a global scale could help capture atmospheric carbon and mitigate climate change. Bastin et al. used direct measurements of forest cover to generate a model of forest restoration potential across the globe (see the Perspective by Chazdon and Brancalion). Their spatially explicit maps show how much additional tree cover could exist outside of existing forests and agricultural and urban land. Ecosystems could support an additional 0.9 billion hectares of continuous forest. This would represent a greater than 25% increase in forested area, including more than 200 gigatonnes of additional carbon at maturity.Such a change has the potential to store an equivalent of 25% of the current atmospheric carbon pool. Science , this issue p. 76 ; see also p. 24

Abstract In the field of innovative power sources, photovoltaic are playing an important role as new clean energy generators. The performances being dependent on instantaneous weather condition, photovoltaic sources are usually equipped with an auxiliary energy storage device. There are applications where the opportunity to couple the photovoltaic source with ultracapacitor can be taken into account. The aim of the paper is to study the performances of a hybrid system constituted by photovoltaic and ultracapacitor sources. In particular, the paper deals with the study of the ultracapacitor rate design for photovoltaic systems feeding pulsing loads. The results of the study, which can also be referred to temporary unfavourable weather conditions, have been validated by experimental data. In the final part of the paper, some considerations on economical implications about the dimensioning of a photovoltaic–ultracapacitor systems are drawn.

Abstract In the last years, electric vehicles (EVs) are getting significant consideration as an environmental-sustainable and cost-effective alternative over conventional vehicles with internal combustion engines (ICEs), for the mitigation of the dependence from fossil fuels and for reduction of Green-House Gasses (GHGs) emission. However, many challenges are still ongoing to their large scale implementation. Among them, the negative impact on the electrical grid operation in case of an uncoordinated contemporary charging of a huge number of EVs. In the recent literature different solutions are proposed for handling the peak demand of EVs and the related problems. One answer is offered by the implementation of EV charging strategies, through aggregation agents, for containing the impact on the grid, guaranteeing the quality of the service. The implementation of a real charging strategy is strictly related to a deployment of smart-grid technologies, such as smart meters, Information and Communication Technologies (ICTs) and energy storage systems (ESSs). In particular ESSs are playing a fundamental role in the general smart grid paradigm, and can become fundamental for the integration in the new power systems of EV fast charging stations of the last generation: in this case the storage can have peak shaving and power quality functions and also to make the charge time shorter. In the present paper, an overview on the different types of EVs charging stations, in reference to the present international European standards, and on the storage technologies for the integration of EV charging stations in smart grid is reported. Then a real implementation of EVs fast charging station equipped with an ESS is deeply described. The system is a prototype, designed, implemented and now available at ENEA (Italian National Agency for New Technologies, Energy and Sustainable Economic Development) labs. A wide experimental activity has been performed on the prototype system in order to test its functionalities in the integration in a smart grid available at the same ENEA lab, including a smart metering system. The integration has been possible thanks to the use of a customized communication protocol, developed by the researchers and here described. The results of the experimental tests show that the system has a good performance in the implementation of peak shaving functions, in respect of the main distribution grid, making the prototype like a network nearly zero-impact system.

The demand for cheap and clean energy sources, not based on fossil fuels and having low impact on the environment, is becoming nowadays an urgent matter. In this regard photovoltaic (PV) power generation technology is one of the most promising. A large variety of photovoltaic devices, or most commonly “solar cells”, is currently on market but all of them share an identical research aspect: the need of increase their photovoltaic conversion efficiency in a cost effective way. In addition to improving the electronic properties of the materials used for solar devices construction, there is a very promising approach towards the efficiency enhancement based on the so called Light Management (LM) techniques. LM techniques are based on the introduction of particular photonic nanostructures which depending on the positioning along the cell architecture and depending on their morphological characteristics, can serve for the obtaining of different phenomena including: diffractive effects, modulation of the refractive index, coupling to waveguide modes through surface structuring, and modification of the photonic band structure of the device. Anyway, the goal of LM concept is the enhance of the probability of photons interaction with cell active layer for the generation of an increased quantity of charge carriers involved in the photovoltaic process. Continuous improvement in nanotechnology manufacturing field have led to a great attention for LM techniques applied to photovoltaics and the present work has given a contribute to this interesting field, focusing on a particular type of PV device, Dye Sensitized Solar Cells (DSC). A Bragg grating with defined morphological parameters (theoretically predicted by FEM calculation) has been realized on a high performance photoresist by means of Laser Interference Lithography (LIL) and then replicated on a mesoporous TiO2 layer. Replication process takes place by means of a low-cost Soft Lithographic (SL) process which exploits a PDMS mold for pattern transferring from one layer to the other. The nanostructures good quality replication, over a large area have been demonstrated by microscopic analysis. The nanostructured TiO2 layer was then soaked into a dye and the DSC cell assembled. PV properties of the build-up nanostructured cell and those of a traditional bare one, both realized following identical experimental procedures and differing only for the Bragg grating presence, were compared. Results confirmed an enhanced efficiency, in term of IPCE, of 31% for the nanostructured cell. Therefore, the most important achievement of this study has been the successful easy and low cost TiO2 nanostructuring. The second part of this work concerns on preliminary guidelines for the realization and ordering of different type of nanostructures. In particular a LIL method for 2D Bragg grating structure production has been proposed to be employed for photovoltaic antireflective coating. A transfer method that exploit PDMS mold to align gold nanoparticles (NPs) on a PEDOT:PSS layer of an organic solar cell was applied. The deposition and ordering of such Au NPs along specific patterns, permits to combine the photonic effect, whose effectiveness has been demonstrated in the first part of the work, with the plasmonic one. The presented result demonstrated the great potential of low-cost soft lithographic procedures in LM field.