Mathematical Models for Improving Flexibility within the Smart Grid domain

One of the most important topics of the last decades has been finding energy sources who can replace fossil fuels. Renewable energy is a good candidate, being virtually inexhaustible and more environment-friendly. In order to allow for this transition, electric energy grids have evolved and have become new objects, called \emph{smart grids}. However, the complexity of this new type of grid brings new issues and challenges, which are currently object of study for many researchers. The purpose of this thesis is to showcase some of these problems, and to build mathematical models and algorithms in order to solve them, by leveraging a new property relative to energy loads: flexibility. Since smart devices are becoming more common and they can be remotely controlled, manipulation of energy profiles is possible, and this is a powerful tool for the management of smart grids. Going more into detail, a framework for managing demand response, peak shaving and energy trading has been designed by the means of a combinatorial approach, and it has been enhanced by exploitation of parallel computing. Moreover, an incentive mechanism for usage of renewable energy has been analyzed and improved, by changing some functions which define its behavior. This mechanism has also been examined from a game-theoretic point of view, and it has been further improved in order to always guarantee an agreement between users for flexibility usage. Finally, a decentralized, multi-agent system approach has been used to solve the problems of cost optimization and congestion management. Most of the content of this thesis derives from research works published in journals and conferences

THE USE OF GEOMEMBRANES TO INCREASE EFFICIENCY, RELIABILITY AND SAFETY OF HYDROTECHNICAL STRUCTURES

Geomembranes are thin, flexible sheets with very low permeability. They are manufactured in a controlled factory environment starting from a mix of polymeric resins and additives, which is extruded to form the sheets. Performance properties of the final product depends on the characteristics of the single components, on the specific material design, and on the manufacturing method. Critical properties of a geomembrane for lining hydraulic structures are: imperviousness, which must be maintained over the whole service life of the structure; strength and elongation capability, which must enable the geomembrane to withstand deformations of the underlying support; resistance against ageing, so to enable an acceptable service life. Leakage through a hydraulic structure can affect its efficiency if not become a threaten for its safety. Geomembranes with proper performance properties can be essential in ensuring efficiency, reliability and safety of hydraulic structures. This paper describes a fewamong the \u3e250 projects that have been performed by the affiliation of the authors

A morphometric study of human submandibular gland in type 2 diabetic status

Diabetes Mellitus Type 2 represents one of the principal diseases that afflict the world population. It is well documented that diabetes affects both morphology and function of several organs. In diabetic rats significant structural changes have been demonstrated in salivary glands, such as accumulation of secretory material and lipid droplets within secretory cells, parenchymal degeneration and its replacement with fibrous connective tissue (1). With regard to human salivary glands, the data are scanty and conflicting. Our work, carried out by light and electron microscopy, is based on the evaluation of the morphological changes which occur in human submandibular glands of diabetic with respect to non diabetic patients. Surgical fragments of glandular tissue were fixed, dehydrated, and processed for light and electron microscopy. Randomly chosen images were analyzed with Image Pro Plus software to record the dimension of acini, serous cells, secretory granules and other variables. Data were analyzed by Student’s t-test and Mann Whitney test. In diabetic glands statistically significant morphological changes were observed, such as enlargement of serous acini and increase of secretory granules area. These results suggest that the secretory activity of human submandibular gland is severely affected by the diabetic status. Obviously these data need to be confirmed with further measurements in order to explain better how diabetes affects human salivary glands

Absence of Structural Impact of Noble Nanoparticles on P3HT: PCBM Blends for Plasmon Enhanced Bulk-Heterojunction Organic Solar Cells Probed by Synchrotron Grazing Incidence X-Ray Diffraction

The incorporation of noble metal nanoparticles, displaying localized surface plasmon resonance, in the active area of donor-acceptor bulk-heterojunction organic photovoltaic devices is an industrially compatible light trapping strategy, able to guarantee better absorption of the incident photons and give an efficiency improvement between 12% and 38%. In the present work, we investigate the effect of Au and Ag nanoparticles blended with P3HT: PCBM on the P3HT crystallization dynamics by synchrotron grazing incidence X-ray diffraction. We conclude that the presence of (1) 80nm Au, (2) mix of 5nm, 50nm, 80nm Au, (3) 40nm Ag, and (4) 10nm, 40nm, 60nm Ag colloidal nanoparticles, at different concentrations below 0.3 wt% in P3HT: PCBM blends, does not affect the behaviour of the blends themselves

L'immagine del pensiero. L'aura della figura tra antropologia e filosofia

Il saggio svolge un’indagine sull’emergere delle prime forme di figurazione e sul legame che esse intrattengono con la nascita della concettualità umana. Tramite la storia della figura si presenta un grande bivio della storia delle civiltà, la biforcazione essenziale causata dai due grandi modi di mettere all’opera la figura: da una parte l’operazione occidentale del senso, enucleata dalle analisi di Carlo Sini, dall’altra l’espressione figurativa delle trasformazioni naturali colta dall’ideogramma orientale, che produce un alternativo universo di senso, illustrata brillantemente da Fenollosa e Jullien. Attraverso l’evocazione dell’aura dei due diversi universi figurativi si tenta di delineare un percorso genealogico che ricostruisca un’unica immagine di pensiero.The present essay is an investigation about the rise of the earliest forms of figuration and the relationship they have with the birth of human conceptuality. Through the history of the figure it appears a large fork in history of civilization, the essential bifurcation caused by the two great ways to put the figure at work: on the one hand the operation of the Western sense, enucleated by the analysis of Carlo Sini, on the other the figurative expression of natural changes, caught by Eastern ideogram, which produces an alternative way of meaning, illustrated by Fenollosa and Jullien. By evoking the aura of the two different figurative ways, it tries to draw a genealogy that builds a single image of Thought

Grain rotation and lattice deformation during perovskite spray coating and annealing probed in situ by GI-WAXS

We report for the first time on grain rotation in CH3NH3PbI3 perovskite films for ∼12% efficient planar solar cells and present a new method for investigating their texture evolution during thermal annealing. Our technique is based on in situ 2D grazing incidence wide-angle X-ray scattering (GI-WAXS) and employs a 10 keV wide-focussed X-ray beam to simultaneously probe a large number of grains. The ability to track the texture dynamics from a statistically relevant number of spots diffracting from single grains during thermal annealing and in grazing incidence geometry can have applications understanding the processing dynamics of a range of new materials

Heat FlexOffers:a device-independent and scalable representation of electricity-heat flexibility

The increasing relevance of Renewable Energy Sources (RES) makes energy flexibility an extremely important aspect, not only regarding electricity, but also for other energy vectors such as heat. Because of this, there is the need for a flexibility model which can i) provide a common representation of flexibility for different device types, ii) perform aggregation, optimization and disaggregation while scaling for long time horizons and many devices, iii) capture most of the available flexibility, and iv) support energy conversion between different vectors. Properties i)-iii) are addressed by FlexOffer (FO), a device-independent model that describes energy constraints in an approximate yet accurate way. This paper proposes an extension of FOs, Heat FlexOffers (HFOs), capable of modeling flexibility for different energy vectors such as heat and handling energy conversion, and therefore addressing iv) as well as i)-iii). HFOs can model the optimal power curve for heat pumps, and can provide constraints for continuous optimization problems while complying to the Smart Grid-Ready (SG-Ready) interface, which operates on discrete states. We show that HFOs are very accurate, being able to retain up to of total flexibility before aggregation and of it after aggregation. HFOs aggregation is scalable, as 2 · 10^6 devices can be aggregated for a 24 hours time horizon, vastly outperforming exact models as they fail to aggregate more than 500 devices.</p