Search results for "Video image"
showing 5 items of 5 documents
Traffic data acquirement by unmanned aerial vehicle
2017
This paper presents a methodology aimed to acquire traffic flow data through the employment of unmanned aerial vehicles (UAVs). The study is focused on the determination of driving behavior parameters of road users and on the reconstruction of traffic flow Origin/Destination matrix. The methodology integrates UAV flights with video image processing technique, and the capability of geographic information systems, to represent spatiotemporal phenomena. In particular, analyzing different intersections, the attention of the authors is focused on users’ gap acceptance in a naturalistic drivers’ behavior condition (drivers are not influenced by the presence of instruments and operators on the roa…
High-speed intensified video recordings of sprites and elves over the western Mediterranean Sea during winter thunderstorms
2010
We report the first intensified high‐speed video images of elves, sprites, and halos observed in Europe. All the events corresponded to winter season thunderstorms over the Mediterranean Sea. The observations comprise many elves generated by both cloud‐to‐ground lightning current polarities. In 8 of the 14 sprite observations we observed an elve previous to the sprite. In three cases we observed also an elve quickly followed by a halo and a sprite. In several observations we observed lightning light before the mesospheric transient luminous event. We present a case where the lightning from cloud tops was visible during the entire event. Thanks to the high‐speed videos and their resolution a…
Educational value of surgical videos on YouTube: quality assessment of laparoscopic appendectomy videos by senior surgeons vs. novice trainees
2019
Background To prepare for surgery, surgeons often recur to surgical videos, with YouTube being reported as the preferred source. This study aimed to compare the evaluation of three surgical trainees and three senior surgeons of the 25 most viewed laparoscopic appendectomy videos listed on YouTube. Additionally, we assessed the video conformity to the published guidelines on how to report laparoscopic surgery videos (LAP-VEGaS). Methods Based on the number of visualization, the 25 most viewed videos on laparoscopic appendectomy uploaded on YouTube between 2010 and 2018 were selected. Videos were evaluated on the surgical technical performance (GOALS score), critical view of safety (CVS), and…
Integrating Advanced Visual Information with Ball Projection Technology Constrains Dynamic Interceptive Actions
2014
The role of advanced visual information in ball catching was investigated by integrating video images of action and ball projection technology in four different conditions: Integrated video and ball projection (VBP), Video-Only (VO), Ball Projection-Only (BPO) and Misleading Ball projection (MBP). Hand kinematics and gaze behaviour data were collected from participants who attempted to catch balls one handed in all conditions. During VBP, catching performance was more successful, tracking of the ball occurred earlier and lasted longer, with maximum grip aperture emerging earlier with a slower maximum velocity than in BPO. During VO, movement emerged later than VBP, with larger maximum and m…
Image Processors for Digital Angiography Algorithms and Architectures
1986
After a period of experimental and clinical development,(1–9) digital processing of angiographic X-ray video image sequences is now routinely applied in clinical and research work. The clinical advantages offered by this approach have been discussed in several reports.(10–12) The primary application is the improved visualization of regions of the heart and circulation opacified by X-ray contrast material during angiographic and angiocardiographic examinations. More complex techniques are being developed for improved functional analysis based on digitized angiograms. Technically, the digital techniques also potentially offer improved means of acquiring, storing, and handling images when comp…