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…
Energy consumption model of aerial urban logistic infrastructures
2021
In the last decade, logistic systems based on small aerial vehicles (drones) have become attractive for urban delivery operations as a sustainable alternative to ground vehicles because they are not affected by the congestion of the road network, thus allowing for faster and more reliable services. Aerial logistic systems, however, require a substantially different approach to operations management and need specifically designed supportive infrastructures. While the research on urban aerial delivery mostly focuses on the optimization vehicle operations, the appropriate design of supportive infrastructures is seldom considered. This paper focuses on the energy efficiency of aerial logistic s…
Applications and development of acoustic and microwave atomic force microscopy for high resolution tomography analysis
2016
The atomic force microscope (AFM) is a powerful tool for the characterization of organic and inorganic materials of interest in physics, biology and metallurgy. However, conventional scanning probe microscopy techniques are limited to the probing surface properties, while the subsurface analysis remains difficult beyond nanoindentation methods. Thus, the present thesis is focused on two novel complementary scanning probe techniques for high-resolution volumetric investigation that were develop to tackle this persisting challenge in nanometrology.The first technique considered, called Mode Synthesizing Atomic Force Microscopy (MSAFM), has been exploited in collaboration with Dr. Laurene Teta…
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…
Numerical simulation of wave energy production through experimental tool
2017
Wave energy is highly desirable resource and recent international reports underline its major relevance on global renewable energy in future. In general, the first step is a correct WEC (Wave Energy Converter) sizing and design. The aim of this paper is a presentation of an application of one experimental tool to define the external floating structure of WEC realized by University of Palermo. This new electric device could be another energy possibility for small islands in the Mediterranean Sea as Pantelleria, Lampedusa or Malta.
An Algorithm for Optimal Sizing of BESS in Smart Islands Energy Communities: the Case of Pantelleria
2021
Energy Communities (EC) are a promising solution to reduce both the carbon footprint and the impact of Renewable Energy Sources (RES) on the distribution grid. Based on a simple energy sharing principle, EC can be decisive in the next future energy transition of some problematic territories, like small islands not supplied by the main power grid. By integrating Battery Energy Storage Systems (BESS), it is possible to improve the EC performance. However, due to the still high BESSs unit prices, the goal of this work is to find the optimal size of BESSs, under various conditions, which combines the need to maximize shared energy and the possible revenue of EC actors. To set this multi-objecti…
Filtering and emission area identification in the Time Resolved Imaging data
2012
Abstract Time Resolved Imaging (TRI) acquisitions allow precise timing analysis of emission spots. Up to date technologies deeply challenge their isolation by hiding the weak ones, under sizing or over sizing visually detectable emission spots and finally by jeopardizing timing resolution. We report on an algorithm based on 1 and 2D signal processing tools which automates the identification of emission sites and optimizes separation between noise and useful signal, even for weak spots surrounding strong emission areas. The application of the algorithm on several sets of data from different types of devices and their results are also discussed.
Modeling of interference fits taking form defects of the surfaces in contact into account
2011
Abstract The technique of assembly by shrink fit is increasingly used today. However, the methodology of parts sizing has not changed in 50 years. Assembled parts are assumed to have accurate dimensions and very low form defects. This has the disadvantage of increasing the cost of parts production. To reduce manufacturing costs, the study of the influence of form defects on the characteristics of assembly strength is essential. Taking default form into account assumes that the tightening (difference between the diameters of the shaft and the bore) is defined. In the case under consideration, the tightening depends locally on the radius. Two definitions of the tightening are proposed: maximu…
Instrument Characterization and First Application of the Single Particle Analysis and Sizing System (SPASS) for Atmospheric Aerosols
2005
We describe here the instrumental setup and first experiments with the mobile single particle analysis and sizing system (SPASS) for the on-line characterization of single atmospheric aerosol particles. Aerosols are introduced into the SPASS via a differentially pumped particle inlet system using an aerodynamic lens that forms a narrow particle beam. The particles are sized with a two-laser velocimeter and subsequently desorbed and ionized with a high-power pulsed Nd:YAG laser operating at 266 nm. Positive and negative ions formed are simultaneously detected in a bipolar time-of-flight mass spectrometer. Thus, the size and chemical composition of single aerosol particles can be characterize…
“Nos inventamos un mundo que no existía”. Una profesión de riesgo.
2019
Since the end of Franco's dictatorship, editorial censorship has been an object of interdisciplinary study that has been incorporating, to the initial analysis of the constitution and nature of censorship, the study of a variety of case studies that are resizing the phenomenon. On the one hand, in the context of memory studies, it is necessary to analyze what effects censorship had on the configuration of cultural memory. On the other hand, censorship has a considerable effect on publishing strategies, both in itself and because it fosters self-censorship and countercensorship. In particular, this article explores the work of women publishers who, in the Barcelona of the 1960s and 1970s, op…