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Real-time space object tracklet extraction from telescope survey images with machine learning

Astrodynamics 2022年第2期6卷 205-218页

作者： andrea de vittori Riccardo Cipollone Pierluigi Di Lizia Mauro Massari department of Aerospace Science and Technology Politecnico di MilanoMilano Via La Masa 3420156Ita

In this study,a novel approach based on the U-Net deep neural network for image segmentation is leveraged for real-time extraction of tracklets from optical *** in all machine learning(ML)applications,a series of steps is required for a working pipeline:dataset creation,preprocessing,training,testing,and post-processing to refine the trained network *** websites usually lack ready-to-use datasets;thus,an in-house application artificially generates 360 labeled ***,this software tool produces synthetic night-sky shots of transiting objects over a specified location and the corresponding labels:dual-tone pictures with black backgrounds and white ***,both images and labels are downscaled in resolution and normalized to accelerate the training *** assess the network performance,a set of both synthetic and real images was *** the preprocessing phase,real images were fine-tuned for vignette reduction and background brightness ***,they are down-converted to eight *** the network outputs labels,post-processing identifies the centroid right ascension and declination of the *** average processing time per real image is less than 1.2 s;bright tracklets are easily detected with a mean centroid angular error of 0.25 deg in 75%of test cases with a 2 deg field-of-view *** results prove that an ML-based method can be considered a valid choice when dealing with trail reconstruction,leading to acceptable accuracy for a fast image processing pipeline.

关键词： space surveillance and tracking (SST) space debris tracklet telescope images machine learning(ML) U-Net

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Morbidity and psychological impact of prostate biopsy： the future calls for a change

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Asian Journal of Andrology 2014年第3期16卷 415-417页

作者： andrea Minervini Gianni vittori Giampaolo Siena Marco Carini department of Urology University of FlorenceCareggi Hospital Florence Italy.

Currently transrectal ultrasound-guided prostate biopsy （TRUS-Bx） is one of the most common urological procedures, with more than 1 million performed per year in Europe and the United States. Among patients undergoing TRUS-Bx, approximately one-third will receive a diagnosis of prostate cancer （PCa）, while two-thirds receive a negative result on initial biopsy. Negative biopsy patients maintain an estimated risk of repeated biopsy of 12% at I year and 38% at 5 years. 2 Standard TRUS-Bx is likely to systematically miss significant tumors, particularly in the anterior and apical parts of the gland.3 A crucial aim of urologists in the next decade is to increase the accuracy of the procedure and avoid the use of inappropriate biopsies.

关键词： Morbidity psychological impact prostate biopsy

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Assessment of Pollutants in Wet and Dry depositions in a Suburban Area around a Waste-to-Energy Plant (WEP) in Northern Italy

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Journal of Environmental Protection 2013年第5期4卷 16-25页

作者： Livia vittori Antisari Francesca Ventura andrea Simoni Stefano Piana Paola Rossi Pisa Gilmo Vianelloz department of Agricultural Science Alma Mater Studiorum-University of Bologna Bologna Italy

Atmospheric concentrations of many trace elements are significantly affected by human activities, and their quantification in atmospheric deposition can be useful to ascribe to different sources of pollution. An important source of pollution, which creates concern in the inhabitants of neighboring areas, are waste-to-energy-plants, that nonetheless are necessary in the actual management of municipal solid waste. For this reason the waste-to-energy (WEP) plant of Bologna (Italy) was monitored from 2006 to 2008, collecting rainfall water in 6 sites around it. Moreover, dry deposition of pollutants was determined after leaching from leaves, with four samples collected during 2007. Trace elements were analyzed using spectrometry, deposition and fluxes were calculated. Results show that there is a large variability of concentrations of trace elements both in time and space. Moreover, the pollution in the area is quite diffused, with no clear determination of the role of the WEP. As a general remark, elements and trace elements found both in rainfall water and in leaching water from leaves showed a diffused pollution in all the monitored sites, probably due to the WEP but also to industrial/commercial area, large constructions and high traffic roads. In any case the values found in the area are comparable to values detected in similar area all over the world.

关键词： Waste-to-Energy-Plant Atmospheric deposition Heavy Metals Pollutants Rain Water

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