19 research outputs found
Delivery with Uavs: A Simulated Dataset Via Ats
We consider a delivery food service operated by Unmanned Aerial Vehicles (UAVs). Due to the absence of a dataset on UAVs deliveries in the literature, and since it is not possible to perform real tests, we create a dataset using an open-Air Traffic Simulator (ATS). Precisely, we converted a set of food deliveries operated by wheeled vehicles, proposed in the literature [1], into a set of simulated UAVs deliveries. For each delivery, we ran a UAV flight from the source to the destination. The results showed that, as expected, the UAV\u27s course is shorter than the vehicle trajectory on the ground because the UAV follows a Euclidean path. Following that path, UAVs can be 5 to 8 times faster than wheeled vehicle, in absence of wind. Highly important, the ATS simulator allows to take care of the wind impact in a realistic way. Tailwind increases UAVs speed which becomes up to 10 times faster than the wheeled vehicles, whereas the headwind and crosswind slowdown the UAVs as the traffic slowdown the wheeled vehicles. Our work proves that air traffic simulators pave the way for realistic simulations of UAVs systems
Sensorimotor recalibration of postural control strategies occurs after whole body vibration
Efficient postural control results from an effective interplay between sensory feedbacks integration and muscle modulation and can be affected by ageing and neuromuscular injuries. With this study, we investigated the effect of whole-body vibratory stimulation on postural control strategies employed to maintain an upright posture. We explored both physiological and posturography metrics, through corticomuscular and intramuscular coherence, and muscle networks analyses. The stimulation disrupts balance in the short term, but leads to a greater contribution of cortical activity, necessary to modulate muscle activation via the formation of (new) synergies. We also observed a reconfiguration of muscle recruitment patterns that returned to pre-stimulation levels after few minutes, accompanied by a slight improvement of balance in the anterior–posterior direction. Our results suggest that, in the context of postural control, appropriate mechanical stimulation is capable of triggering a recalibration of the sensorimotor set and might offer new perspectives for motor re-education
orthostatic hypotension does not increase cardiovascular risk in the elderly at a population level
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Big Web Colors: Analyzing the World Top Sites
Colors are obviously important for web sites, but how much? in this paper we try to study the problem of abstracting from the actual content, and analyze if and how colors in images have a higher-level fundamental importance. Focusing on the world top web sites, we collected a large pool (almost two millions) of images, and then investigated the relationships of colors with the attractiveness of a page. Can colors alone boost the success of a page, and in what terms? To answer this question we developed an experiment involving a large number of people, measuring how and how much colors affect a page, abstracting from the content. The results show that, rather surprisingly, colors do have a more fundamental significance that can be decoupled from the underlying shapes. We provide qualitative and quantitative insights on how important colors are, and how they actually impact the success of a site in terms of user perception
Verso una forma di gestione della malga rispettosa dell' ambiente e delle esigenze nutrizionali della vacca da latte
Uso del territorio, impatto ambientale, benessere degli animali e sostenibilit\ue0\ua0 economica dei sistemi di allevamento della vacca da latte presenti in montagna. Il caso di studio dell' Altopiano di Asiago.
Un disciplinare per la gestione degli alpeggi dell' altopiano di Asiago nel rispetto dell' ambiente e delle esigenze nutrizionali della vacca da latte.
Convegno della Societ\ue0\ua0 per lo Studio e Valorizzazione dei Sistemi Zootecnici Alpin
A Comprehensive Investigation on Range-Free Localization Algorithms with Mobile Anchors at Different Altitudes
In this work, the problem of localizing ground devices (GDs) is studied comparing the performance of four range-free (RF) localization algorithms that use a mobile anchor (MA). All the investigated algorithms are based on the so-called heard/not-heard (HnH) method, which allows the GDs to detect the MA at the border of their antenna communication radius. Despite the simplicity of this method, its efficacy in terms of accuracy is poor because it relies on the antenna radius that continuously varies under different conditions. Usually, the antenna radius declared by the manufacturer does not fully characterize the actual antenna radiation pattern. In this paper, the radiation pattern of the commercial DecaWave DWM1001 Ultra-Wide-Band (UWB) antennas is observed in a real test-bed at different altitudes for collecting more information and insights on the antenna radius. The compared algorithms are then tested using both the observed and the manufacturer radii. The experimental accuracy is close to the expected theoretical one only when the antenna pattern is actually omnidirectional. However, typical antennas have strong pattern irregularities that decrease the accuracy. For improving the performance, we propose range-based (RB) variants of the compared algorithms in which, instead of using the observed or the manufacturer radii, the actual measured distances between the MA and the GD are used. The localization accuracy tremendously improves confirming that the knowledge of the exact antenna pattern is essential for any RF algorithm