283 research outputs found
Generic Drone Control Platform for Autonomous Capture of Cinema Scenes
The movie industry has been using Unmanned Aerial Vehicles as a new tool to
produce more and more complex and aesthetic camera shots. However, the shooting
process currently rely on manual control of the drones which makes it difficult
and sometimes inconvenient to work with. In this paper we address the lack of
autonomous system to operate generic rotary-wing drones for shooting purposes.
We propose a global control architecture based on a high-level generic API used
by many UAV. Our solution integrates a compound and coupled model of a generic
rotary-wing drone and a Full State Feedback strategy. To address the specific
task of capturing cinema scenes, we combine the control architecture with an
automatic camera path planning approach that encompasses cinematographic
techniques. The possibilities offered by our system are demonstrated through a
series of experiments
Performance study update of observations in divergent mode for the Cherenkov Telescope Array
Due to the limited field of view (FoV) of Cherenkov telescopes, the time
needed to achieve target sensitivity for surveys of the extragalactic and
Galactic sky is large. To optimize the time spent to perform such surveys, a
so-called "divergent mode" of the Cherenkov Telescope Array Observatory (CTAO)
was proposed as an alternative observation strategy to the traditional parallel
pointing. In the divergent mode, each telescope points to a position in the sky
that is slightly offset, in the outward direction, from the original center of
the field of view. This bring the advantage of increasing the total
instantaneous arrays' FoV. From an enlarged field of view also benefits the
search for very-high-energy transient sources, making it possible to cover
large sky regions in follow-up observations, or to quickly cover the
probability sky map in case of Gamma Ray Bursts (GRB), Gravitational Waves
(GW), and other transient events. In this contribution, we present the proposed
implementation of the divergent pointing mode and its first preliminary
performance estimation for the southern CTAO array
Performance study update of observations in divergent mode for the Cherenkov Telescope Array
Due to the limited field of view (FoV) of Cherenkov telescopes, the time
needed to achieve target sensitivity for surveys of the extragalactic and
Galactic sky is large. To optimize the time spent to perform such surveys, a
so-called "divergent mode" of the Cherenkov Telescope Array Observatory (CTAO)
was proposed as an alternative observation strategy to the traditional parallel
pointing. In the divergent mode, each telescope points to a position in the sky
that is slightly offset, in the outward direction, from the original center of
the field of view. This bring the advantage of increasing the total
instantaneous arrays' FoV. From an enlarged field of view also benefits the
search for very-high-energy transient sources, making it possible to cover
large sky regions in follow-up observations, or to quickly cover the
probability sky map in case of Gamma Ray Bursts (GRB), Gravitational Waves
(GW), and other transient events. In this contribution, we present the proposed
implementation of the divergent pointing mode and its first preliminary
performance estimation for the southern CTAO array.Comment: Presented at the 38th International Cosmic Ray Conference (ICRC
2023), 2023 (arXiv:2309.08219
Recommended from our members
The FY2007 National Defense Authorization Act: Selected Military Personnel Policy Issues
This report examines a number of issues being considered by Congress as the FY2007 National Defense Authorization Act evolves. In each case, a brief synopsis is provided that includes background information, a comparison of the House and Senate provisions, if any, and a brief discussion of the issue. Where appropriate, other CRS products are identified to provide more detailed background information and analysis of the issue. For each issue, a CRS analyst is identified and contact information is provided
Fast Evolutionary Adaptation for Monte Carlo Tree Search
This paper describes a new adaptive Monte Carlo Tree Search (MCTS) algorithm that uses evolution to rapidly optimise its performance. An evolutionary algorithm is used as a source of control parameters to modify the behaviour of each iteration (i.e. each simulation or roll-out) of the MCTS algorithm; in this paper we largely restrict this to modifying the behaviour of the random default policy, though it can also be applied to modify the tree policy
Oncoplastic and reconstructive surgery in SENONETWORK Italian breast centers: lights and shadows
Highlights: • Despite the significance of oncoplastic procedure, an italian database is lacking. • Senonetwork established a multidisciplinary survey to assess their safety and efficacy. • Reconstructive outcomes were positive across low and high-volume centers. • After mastectomy, implant-based techniques are common. DTI reconstruction is advantageuos. • This contributes to the global understanding of effective strategies against breast cancer
The variability patterns of the TeV blazar PG 1553+113 from a decade of MAGIC and multi-band observations
PG 1553+113 is one of the few blazars with a convincing quasi-periodic
emission in the gamma-ray band. The source is also a very high-energy (VHE;
>100 GeV) gamma-ray emitter. To better understand its properties and identify
the underlying physical processes driving its variability, the MAGIC
Collaboration initiated a multiyear, multiwavelength monitoring campaign in
2015 involving the OVRO 40-m and Medicina radio telescopes, REM, KVA, and the
MAGIC telescopes, Swift and Fermi satellites, and the WEBT network. The
analysis presented in this paper uses data until 2017 and focuses on the
characterization of the variability. The gamma-ray data show a (hint of a)
periodic signal compatible with literature, but the X-ray and VHE gamma-ray
data do not show statistical evidence for a periodic signal. In other bands,
the data are compatible with the gamma-ray period, but with a relatively high
p-value. The complex connection between the low and high-energy emission and
the non-monochromatic modulation and changes in flux suggests that a simple
one-zone model is unable to explain all the variability. Instead, a model
including a periodic component along with multiple emission zones is required.Comment: Accepted for publication in Monthly Notices of the Royal Astronomical
Society. 19 pages, 9 figures. Corresponding authors: Elisa Prandini, Antonio
Stamerra, Talvikki Hovatt
MAGIC detection of GRB 201216C at z = 1.1
Gamma-ray bursts (GRBs) are explosive transient events occurring at cosmological distances, releasing a large amount of energy as electromagnetic radiation over several energy bands. We report the detection of the long GRB 201216C by the MAGIC telescopes. The source is located at z = 1.1 and thus it is the farthest one detected at very high energies. The emission above 70 GeV of GRB 201216C is modelled together with multiwavelength data within a synchrotron and synchrotron self-Compton (SSC) scenario. We find that SSC can explain the broad-band data well from the optical to the very-high-energy band. For the late-time radio data, a different component is needed to account for the observed emission. Differently from previous GRBs detected in the very-high-energy range, the model for GRB 201216C strongly favours a wind-like medium. The model parameters have values similar to those found in past studies of the afterglows of GRBs detected up to GeV energies
Multimessenger Characterization of Markarian 501 during Historically Low X-Ray and γ-Ray Activity
We study the broadband emission of Mrk 501 using multiwavelength observations from 2017 to 2020 performed with a multitude of instruments, involving, among others, MAGIC, Fermi's Large Area Telescope (LAT), NuSTAR, Swift, GASP-WEBT, and the Owens Valley Radio Observatory. Mrk 501 showed an extremely low broadband activity, which may help to unravel its baseline emission. Nonetheless, significant flux variations are detected at all wave bands, with the highest occurring at X-rays and very-high-energy (VHE) 3-rays. A significant correlation (>3σ) between X-rays and VHE 3-rays is measured, supporting leptonic scenarios to explain the variable parts of the emission, also during low activity. This is further supported when we extend our data from 2008 to 2020, and identify, for the first time, significant correlations between the Swift X-Ray Telescope and Fermi-LAT. We additionally find correlations between high-energy 3-rays and radio, with the radio lagging by more than 100 days, placing the 3-ray emission zone upstream of the radio-bright regions in the jet. Furthermore, Mrk 501 showed a historically low activity in X-rays and VHE 3-rays from mid-2017 to mid-2019 with a stable VHE flux (>0.2 TeV) of 5% the emission of the Crab Nebula. The broadband spectral energy distribution (SED) of this 2 yr long low state, the potential baseline emission of Mrk 501, can be characterized with one-zone leptonic models, and with (lepto)-hadronic models fulfilling neutrino flux constraints from IceCube. We explore the time evolution of the SED toward the low state, revealing that the stable baseline emission may be ascribed to a standing shock, and the variable emission to an additional expanding or traveling shock. © 2023. The Author(s). Published by the American Astronomical Society
- …