196,100 research outputs found
Positioning with GNSS and 5G: Analysis of Geometric Accuracy in Urban Scenarios
No full textGNSS positioning in urban scenarios suffers for the scarce visibility of satellites. Integration with 5G services for positioning could improve this situation. In this paper, the digital surface models (DSMs) relevant to different urban scenarios, namely residential streets and urban canyons, are simulated around one observer in northern Italy (Milano) for one day of the year chosen as an example. The time series of the number of in-view GNSS satellites, their geometry and the derived quality indexes (position dilution of precision (PDOP)) are computed and analyzed. As expected, in urban canyons, a significant number of epochs does not provide four satellites within view, and many more epochs present really mediocre PDOPs. In residential streets, the situation is always quite fair. Different geometric configurations of 5G base stations are simulated around the observer. The availability of 5G times of arrival (ToAs) and their differences (TDoAs) is hypothesized, and the integration of these observations with GNSS pseudoranges is analyzed, again in terms of the PDOPs. In residential streets, 5G availability improves the positioning. In urban canyons, the optimal configuration of 5G base stations (five base stations around the observer) completely solves the positioning problem for all the epochs of the day. Less favorable configurations (four and three base stations) improve epochs with poor PDOPs in a GNSS-only configuration. They allow the positioning of epochs with few satellites but cannot completely replace the GNSS
Delle fortificationi de M. Galasso Alghisi da Carpi ... libri tre
No full textEDIT16 CNCE 1140*4, a-d6,e4, A-C6, D8, E6, F8, G6, H4Handschriftliches Exlibris: "Biblioth. Archid. Ferdinandi" 990020167720205503_0001 Exemplar der ETH-BIBHandschriftliches Exlibris: "Bibliothecae Archid. Ferdinandi" 990020167720205503_0002 Exemplar der ETH-BI
Nonlinear Multi-Frequency Converter Array for Vibration Energy Harvesting in Autonomous Sensors
No full textAbstractThis work proposes and experimentally validates a vibration energy harvester which combines the multi-frequency and nonlinear approaches into a converter array. The converter array consists of four piezoelectric cantilevers composed of ferromagnetic substrates with screen-printed lead zirconate titanate (PZT) layers coupled with a single permanent magnet elastically suspended on the array base in order to create a nonlinear behaviour. The presence of a moving magnet and the possibility to realize cantilevers with different potential curves can be useful to obtain a collective nonlinear behaviour due to strong coupling irrespective of the amplitude of the mechanical excitation, therefore increasing the overall effectiveness of the converter array. The experimental results confirm that combining cantilevers with different potential curves can be useful to obtain a collective bistable behaviour, therefore increasing the overall effectiveness of the converter array
La stima della Exposure at Default nei Sistemi di Rating Interni
No full textScopo di questo articolo è presentare alcune metodologie di stima della EAD e le relative implicazioni di carattere operativo frutto dell’esperienza maturata nell’ambito dello sviluppo di un sistema di rating intern
Portable Battery-Less Noncontact Temperature Measurement System Powered On Demand by Human Action
No full text
Active rectifier circuits with sequential charging of storage capacitors (SCSC) for energy harvesting in autonomous sensors
No full textAbstractIn this paper, different configurations of self-powered active rectifier circuits for energy harvesting in autonomous sensors are proposed. The circuits perform the conversion of the AC voltage provided by the mechano-electrical energy converter, and store the energy into multiple capacitors. The proposed Sequential Charging of Storage Capacitors (SCSC) technique has been developed to improve the energy extracted from converters with non-deterministic output voltage over a limited duration. Experimental results show that SCSC active rectifier circuits allow an increase of up to 147% of the stored energy versus passive rectifiers at same mechanical input
Portable wireless distance measurement system powered by intentional human action
No full textThis work proposes and experimentally validates an handheld distance measurement system powered by energy harvesting through the ElectroMagnetic (EM) effect. The system is entirely battery-less and powered on-demand by the user force exerted on the lever of an hand-crack EM converter. With a single excitation force of about 19.6 N over a lever travel of 2 cm, the proposed system is able to perform a distance measurement between a target object and the embedded ultrasonic sensor, show the reading on a LCD display, and transmit the data through a 433-MHz wireless-UART link to an host PC
Towards usage-oriented business models: an assessment of European capital goods manufacturers
No full textThis paper is part of the T-REX project, funded by the European Commission. An exploratory survey was carried out to analyse the business models of 95 companies, to assess the diffusion of service-oriented business models. We found that business models are in general still product-oriented. Revenue models are dominated by product sales, with a contribution of services close to 20% due to corrective maintenance and spare part sales. Rental or “Pay-per-x” contracts are an almost negligible revenue source. This paper has also defined a set of variables that can be used to describe the business model configuration in servitization contexts
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