Search results for "sizing"
showing 10 items of 112 documents
A Hybrid Energy Storage Sizing for a Vertical Take-off and Landing Electric Aircraft
2021
The energy storage sizing procedure for an all-electric aircraft, characterised by vertical take-off and landing (VTOL), is presented in the paper. In order to define the energy consumption, the propulsion system model has been developed and simulated, referring to a specific configuration of VOLT obtained by the transformation of a very light twin-propeller aircraft named Tecnam P2012 T. Specifically, a flight mission-oriented to air city taxing has been considered. The simulation results highlight the presence of significant peak power during take-off and landing. At the aim of optimising the weight and the volume of the energy storage systems (ESSs), considered a critical issue in all-el…
Guidelines to Select Between Self-Contained Electro-Hydraulic and Electro-Mechanical Cylinder
2020
This research paper presents guidelines on how to select between self-contained electro-hydraulic and electromechanical cylinders. An example based on the motion control of a single-boom crane is studied. The sizing process of the different off-the-shelf components is analyzed in terms of design impact when replacing a traditional valve-controlled hydraulic cylinder. The self-contained electro-hydraulic solution is the best choice when a risk for high impact forces is present, when the required output power level lies continuously above 2 kW, or when installation space, weight, and cost are critical design objectives. However, the electro-mechanical solution is expected to show more control…
A sizing approach for stand-alone hybrid photovoltaic-wind-battery systems: A Sicilian case study
2018
Abstract Solar and wind energy are the two most available renewable energy resources in the world. In this paper, a high-resolution analysis that allows sizing a hybrid photovoltaic-wind turbine-battery banks has been carried out. The analysis aims to minimize the annualized cost of the systems satisfying two reliability constraints. The solution has been obtained numerically by means of an iterative technique. The decision variables are the photovoltaic area, wind turbine radius, and battery capacity. A high-resolution model, based on fuzzy logic inference system, has been developed to evaluate the number of active occupants and the domestic electricity consumption. In order to allow a mor…
A Mutually Stimulating Loop Involving Emx2 and Canonical Wnt Signalling Specifically Promotes Expansion of Occipital Cortex and Hippocampus
2005
The correct size of the different areas composing the mature cerebral cortex depends on the proper early allocation of cortical progenitors to their distinctive areal fates, as well as on appropriate subsequent tuning of their area-specific proliferation--differentiation profiles. Whereas much is known about the genetics of the former process, the molecular mechanisms regulating proliferation and differentiation rates within distinctive cortical proto-areas are still largely obscure. Here we show that a mutual stimulating loop, involving Emx2 and canonical Wnt signalling, specifically promotes expansion of the occipito-hippocampal anlage. Collapse of this loop occurring in Emx2 2/2 mutants …
A multi-objective genetic algorithm for the passenger maritime transportation problem
2014
Over the last years, the transportation demand has continuously increased and a further growth is predicted for the next future especially as regards the maritime sector. As a consequence, shipping companies will be asked to improve the supplied services in order to assure a high quality and time-effective goods and passengers transportation, deriving at the same time their own benefits by minimizing costs. Therefore, the optimization of routes and schedules together with the fleet deployment take a meaningful role on companies profitability and efficiency. In such a perspective, the present paper proposes a multi-objective mathematical programming model to determine a set of routes and sch…
Battery storage systems for peak load shaving applications: Part 1: Operating strategy and modification of the power diagram
2016
Battery Energy Storage Systems (BESSs) are gaining more and more attention in the current global energy landscape, thanks to some peculiar characteristics such as the versatility, modularity, scalability, fast response time, etc. BESSs can advantageously be used in the ancillary services market, in order to provide all the services necessary to ensure the stability and the reliability of the power system. Among other applications, BESS can also be used to shift electricity demand from on-peak to off-peak periods, also contributing to relieve peak demand charges, thus ensuring a saving for the customers. The BESS is charged when the electricity prices are the lowest (during the night) and di…
Hybrid Energy Storage Systems: A Brief Overview
2022
In this paper, a brief overview on the Hybrid Energy Storage Systems (HESSs) is provided. In literature, different architectures are chosen to realize the HESSs, and they are based on the principal aim of the HESSs employment. In this paper, the most used HESS topologies are presented, with particular attention to the active, passive and semiactive topologies, highlighting their characteristics. To have a complete schematic idea of the HESSs application, a focus on the principal sizing methodologies is provided, distinguishing the conventional approaches and the advanced ones, exploiting their main applications. Together with a proper sizing, a correct power-sharing strategy is one of the H…
Solar-assisted heat pumps systems for domestic hot water production in small energy communities
2021
Abstract The paper investigates the energy performances of several configurations of solar-assisted heat pumps equipped with photovoltaic (PV) and photovoltaic-thermal (PVT) panels as well as solar thermal collectors for domestic hot water production. The systems are sized to serve small aggregates of users assumed as micro energy communities in low housing density context in the South of Italy. Electricity storages are also considered to smooth the interaction with the electric grid. Several indices are defined and calculated to guide toward a correct sizing, to check users’ satisfaction and to assess primary energy savings. The results show how the energy consumption from the analysed sys…
Analyzing varieties of (post-enlargement) Europeanization in CEE advocacy organizations across policy fields
2021
This article aims to explain Europeanization processes among advocacy organizations from four post-communist states—Poland, Hungary, Slovenia, and the Czech Republic—which have been subject to strong Europeanization pressures before and after the European Union accession. The authors aim to identify how Central and Eastern European organized interests have adapted their organizational logics to a changing environment in the post-enlargement phase. Specifically, we address the following questions: How do various levels and dimensions of Europeanization of interest organizations differ across policy fields and countries and what determines this diversity? What are the strongest predictors of …
Urban Governance in Latvia: Feeling Urban and Thinking Rural
2019
Urbanisation is affecting not only countries with high number of residents but also with small number. The aim of the research is to explore urbanisation and shrinking city tendencies in a country with small number of residents in the context of globalization and urbanisation. The “donut effect” will be explored in the capital city Riga and ten municipalities nearby. The main research question is to what extent can the classical understanding and perception of urbanisation be applied to small societies and countries, and what kind of effects does the urbanisation create in such dynamically developing countries. There are several interdependent problems, such as the new patterns of urban–rur…