Strongly lensed supernovae at high-redshiftsTanja Petrushevska
, predavanje na tuji univerzi
Opis: The searches and observations of supernovae (SNe) have been motivated by the fact that they are exceptionally useful for various astrophysical and cosmological applications. Most prominently, Type Ia SNe (SNe Ia) have been used as distance indicators showing that the expansion rate of the Universe is accelerating. The strong gravitational lensing effect provides another powerful tool and occurs when a foreground mass distribution is located along the line of sight to a background source. It can happen so that galaxies and galaxy clusters can act as “gravitational telescopes”, boosting the faint signals from distant SNe and galaxies. Thanks to the magnification boost provided by the gravitational telescope, we are able to probe galaxies and SNe that otherwise would be undetectable. Therefore, the combination of the two tools, SNe and strong lensing, in the single phenomenon of strongly lensed SNe, provides a powerful simultaneous probe of several cosmological and astrophysical phenomena. In this talk, I will present some of the past results that have been possible due to the observations of strongly lensed supernovae and anticipate what we can expect in the future from the upcoming telescope surveys.
Ključne besede: supernovae, strong lensing
Objavljeno: 16.03.2023; Ogledov: 107; Prenosov: 0
Polno besedilo (15,67 MB)
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Solving a new variant of the capacitated maximal covering location problem with fuzzy coverage area using metaheuristic approachesAnirban Mukhopadhyay
, Priya Ranjan Sinha Mahapatra
, Soumen Atta
, 2022, izvirni znanstveni članek
Opis: The Maximal Covering Location Problem (MCLP) is concerned with the optimal placement of a fixed number of facilities to cover the maximum number of customers. This article considers a new variant of MCLP where both the coverage radii of facilities and the distance between customer and facility are fuzzy. Moreover, the finite capacity of each facility is considered. We call this problem the capacitated MCLP with fuzzy coverage area (FCMCLP), and it is formulated as a 0–1 linear programming problem. In this article, two classical metaheuristics: particle swarm optimization, differential evolution, and two new-generation metaheuristics: artificial bee colony algorithm, firefly algorithm, are proposed for solving FCMCLP. Each of the customized metaheuristics utilizes a greedy deterministic heuristic to generate their initial populations. They also incorporate a local neighborhood search to improve their convergence rates. New instances of FCMCLP are generated from the traditional MCLP instances available in the literature, and IBM’s CPLEX solver is used to generate benchmark solutions. An experimental comparative study among the four customized metaheuristics is described in this article. The performances of the proposed metaheuristics are also compared with the benchmark solutions obtained from CPLEX.
Ključne besede: Facility Location Problem (FLP), Fuzzy Capacitated Maximal Covering Location Problem (FCMCLP), Particle Swarm Optimization (PSO), Differential Evolution (DE), Artificial Bee Colony (ABC), Firefly Algorithm (FA)
Objavljeno: 08.03.2023; Ogledov: 143; Prenosov: 0
Polno besedilo (2,21 MB)
A METHOD FOR QUANTIFICATION OF MINERAL DUST IN AIR BASED ON OPTICAL ABSORPTION OF PARTICLES CONCENTRATED BY A VIRTUAL IMPACTOR AND A DEVICE PERFORMING THE SAID METHODJEAN SCIARE
, FLORIN UNGA
, MICHAEL PIKRIDAS
, SPIROS BEZANTAKOS
, IASONAS STAVROULAS
, Griša Močnik
, Luka Drinovec
Opis: The present invention belongs to the field of devices and methods for measurement of particle concentration, more precisely to the field of devices and methods for quantification of particles based ontheir physical characteristics, especially with the use of optical means. The invention relates to a method for determination of ambient mineral dust concentration based on optical absorption of particles concentrated by a virtual impactor as well as a device performing the said method. The method comprises the following steps: sampling air samples with particle size smaller than 1 mum (PM1) andsampling air samples with particle size up to 10 mum; concentrating the samples with particle sizes up to 10 mum with a virtual impactor; measuring optical absorption of collected samples at least onewavelength from UV to IR spectre, preferably from 370 to 950 nm, most preferably at 370 nm; subtracting the absorption of the samples with particle size smaller than 1 mum from the absorption of thesample concentrated by the virtual impactor.
Ključne besede: dust, black carbon, aerosol
Objavljeno: 07.03.2023; Ogledov: 144; Prenosov: 0
Polno besedilo (426,73 KB)
Crossing Art, Science and Technology for Innovations through Maker Culture and EducationKristina Pranjić
, Peter Purg
, Jernej Čuček Gerbec
, 2022, objavljeni znanstveni prispevek na konferenci
Ključne besede: Cross-innovation, art thinking, making, interdisciplinary, embodiment, art practice, crafting, innovation, art-sci-tech
Objavljeno: 06.03.2023; Ogledov: 142; Prenosov: 0
Polno besedilo (42,35 MB)