Search results for "Volt"
showing 10 items of 2187 documents
Jaunu tribenzsilatrānu un bissilatrānu sintēze un to elektroķīmiskā oksidēšana
2022
Bakalaura darba ietvaros tika sintezēti vairāki jauni tribenzsilatrāni un bissilatrāni, kā arī veikta to elektroķīmiskā oksidēšana, lai iegūtu atbilstošos katjonu radikāļus, kuru stabilitāti pierādīja uzņemtās voltamperogrammas.
Ancillary Services in the Energy Blockchain for Microgrids
2019
The energy blockchain is a distributed Internet protocol for energy transactions between nodes of a power system. Recent applications of the energy blockchain in microgrids only consider the energy transactions between peers without considering the technical issues that can arise, especially when the system is islanded. One contribution of the paper is, thus, to depict a comprehensive framework of the technical and economic management of microgrids in the blockchain era, considering, for the first time, the provision of ancillary services and, in particular, of the voltage regulation service. When more PV nodes are operating in the grid, large reactive power flows may appear in the branches…
Robust current observer design for DC-DC converters
2014
In recent years several fast response controllers have been proposed for DC-DC converters. The majority of them rely on a cascade control structure involving the inductor's current in the control function as its faster dynamics, respect to output voltage, allows a significant increase in the regulation performance; the drawback is the need of a proper and expensive current sensor. In this paper a simple and robust formulation for the design of a current observer, based on the output voltage measurement is presented. The formulation is common for the three standard DC-DC converters and the resulting observer is robust to load variation. The observers have been tested in a cascade PI control …
Multiple-scan voltammetry and OCP: Archaeometric tools for dating archaeological bronzes
2021
[EN] The application of a multiple-scan strategy to nanosamples taken from 18 cross-sections of Bronze Age arms and armour, as well as two Roman coins using two solid-state electrochemical techniques, the voltammetry of immobilized microparticles (VIMP) and open circuit potential measurements (OCP) is described. The voltammetric responses in contact with aqueous acetate buffer can be attributed to the reduction of cuprite with variable degree of compaction and crystallinity revealing significant differences in the gradient of such properties with depth. Such differences are also revealed by "dry" OCP measurements connecting points in the cross section near and separated from the corrosion l…
ARCHITECTURE AND PHOTOVOLTAICS. Strategies, technologies and novel components for the building envelope
Il principale obiettivo della tesi ha riguardato lo studio di strategie e tecnologie per l’integrazione del fotovoltaico negli edifici, con particolare attenzione verso le tecnologie solari di terza generazione, e la successiva definizione di un componente multifunzionale innovativo per l’involucro edilizio integrato con Dye-sensitized Solar Cells (DSC). Nella prima parte del lavoro, la ricerca si è concentrata sull’analisi del mercato del Building Integrated Photovoltaics (BIPV), sottolineando differenze, limiti e potenzialità di ciascuna tecnologia fotovoltaica. Particolare attenzione, inoltre, è stata rivolta a un numero consistente di casi studio, ossia edifici di nuova costruzione o in…
Challenges in Energy Systems for the Smart-Cities of the Future
2012
In the last years the European Union has actively promoted the renewable energies and the Combined Heat and Power (CHP) also for residential and tertiary buildings. The exploitation of renewable sources and cogeneration seems hampered by the regulatory wall that prohibit for residential, tertiary and commercial buildings the constitution of users clusters. In fact, the unification up to a threshold value of some tens of kVA, at least, can facilitate the installation of renewable energy power plants as solar PV modules or CHP systems (cogeneration) or CCHP systems (tri-generation), overcoming technical and economical barriers and combining several load profiles. The actual distribution syste…
Demand side management and Distributed on Site actions benefits
2013
Global warming and energy demand are nowadays becoming one of the major issues of the third millennium, mainly because human activities seem to have a clear impact on the raise of CO2 emissions as never it has been experienced in the past. Among the different factors affecting CO2 emissions, energy demand from buildings constitutes one of the most important actors. Energy Management (EM) actions can reduce the energy consumption of the system and minimize peaks-level, by using a distributed control over every house. These local actions can greatly contribute to reduce the impact on the global CO2 emissions. An evaluation of the potential energy saving and CO2 emissions reduction on building…
Benefits of a translucent building envelope made of DSC-integrated glass blocks
2015
The aim of this paper is to analyse the benefits deriving from the replacement of the glazed façades of an office building located in Palermo (Sicily) with a new translucent BIPV envelope made of multifunctional glass block panels integrated with Dye-sensitized Solar Cells (DSCs). The analysed 11-storey building is cladded by a curtain wall determining high management costs, especially during summer, in order to maintain indoor comfort. After the design of the building envelope and of the components for the connection of the glass block panels with existing load bearing structure, the energy performance of the building, before and after the replacement of its envelope, were analysed with th…
TRADITION AND MODERNITY OF CATALAN VAULTS: HISTORICAL AND STRUCTURAL ANALYSIS
2012
Il lavoro analizza da diversi punti di vista un particolare tipo di strutture voltate noto come volte catalane (bóveda tabicada) e la tecnica costruttiva correlata. Le volte catalane sono volte realizzate da strati alterni di mattoni e malta, caratterizzate da un esiguo spessore in relazione alle altre dimensioni. Il primo passo presentato nel lavoro è quello di investigare tutti gli aspetti storici al fine di inquadrare sia la tipologia che la tecnica costruttiva correlata all'interno della storia dell'architettura e di individuare le ragioni di un così grande successo lungo i secoli. Successivamente, è stata effettuata una campagna di indagini sperimentali, che completa una precedente, su…
Development of a 3D CZT detector prototype for Laue Lens telescope
2010
We report on the development of a 3D position sensitive prototype suitable as focal plane detector for Laue lens telescope. The basic sensitive unit is a drift strip detector based on a CZT crystal, (similar to 19x8 mm(2) area, 2.4 mm thick), irradiated transversally to the electric field direction. The anode side is segmented in 64 strips, that divide the crystal in 8 independent sensor (pixel), each composed by one collecting strip and 7 (one in common) adjacent drift strips. The drift strips are biased by a voltage divider, whereas the anode strips are held at ground. Furthermore, the cathode is divided in 4 horizontal strips for the reconstruction of the third interaction position coord…