Results 21 to 30 of about 83,297 (253)

Construction Tender Subcontract Selection using Case-based Reasoning

Construction Economics and Building, 2012
Obtaining competitive quotations from suitably qualified subcontractors at tender tim n significantly increase the chance of w1nmng a construction project.
Due Luu, Wily Sher
doaj   +3 more sources

What We Talk about When We Talk about Blazars?

Frontiers in Astronomy and Space Sciences, 2017
After the discovery of powerful relativistic jets from Narrow-Line Seyfert 1 Galaxies, and the understanding of their similarity with those of blazars, a problem of terminology was born.
Luigi Foschini
doaj   +1 more source

Model simulation of heavy metals in river systems: case study the Negro river basin

Revista Facultad de Ingeniería Universidad de Antioquia, 2019
Este trabajo describe la aplicación de un modelo de calidad de agua para la simulación de metales pesados en sistemas fluviales. La estrategia propuesta incluye un enfoque de modelación 1D con la extensión del modelo QUASAR-ADZ para la representación del
Carlos Alberto Palacio-Tobón, Sara Cristina Vieira-Agudelo, Julio Cesar Saldarriaga-Molina, Luis Miguel Ruiz-Jaramillo   +3 more
doaj   +1 more source

Cosmology With Quasars: Predictions for eROSITA From a Quasar Hubble Diagram

Frontiers in Astronomy and Space Sciences, 2020
The effort for understanding the matter and energy content of the Universe and its evolution relies on different probes, such as cosmic background radiation, cluster lensing, supernovae.
Elisabeta Lusso, Elisabeta Lusso
doaj   +1 more source

Gravitationally lensed quasars in Gaia – IV. 150 new lenses, quasar pairs, and projected quasars [PDF]

Monthly Notices of the Royal Astronomical Society, 2022
ABSTRACT We report the spectroscopic follow-up of 175 lensed quasar candidates selected using Gaia Data Release 2 observations following Paper III of this series. Systems include 86 confirmed lensed quasars and a further 17 likely lensed quasars based on imaging and/or similar spectra.
C Lemon, T Anguita, M W Auger-Williams, F Courbin, A Galan, R McMahon, F Neira, M Oguri, P Schechter, A Shajib, T Treu, A Agnello, C Spiniello   +12 more
openaire   +3 more sources

Quasar clustering: evidence for an increase with redshift and implications for the nature of AGNs [PDF]

, 1997
The evolution of quasar clustering is investigated with a new sample of 388 quasars with 0 ...
Bellenger R., Boyle B. J., Boyle B. J., Carrera F. J., Cavaliere A., Cristiani S., Croom S. M., Fabio La Franca, Franceschini A., Georgantopoulos I., Komberg B. V., Matarrese S., Paola Andreani, Shanks T., Shaver P. A., Soltan A., Stefano Cristiani, Zitelli V.   +17 more
core   +3 more sources

Imprints of the super-Eddington accretion on the quasar clustering

, 2017
Super-Eddington mass accretion has been suggested as an efficient mechanism to grow supermassive black holes (SMBHs). We investigate the imprint left by the radiative efficiency of the super-Eddington accretion process on the clustering of quasars using ...
Enoki, Motohiro, Ishiyama, Tomoaki, Kobayashi, Masakazu A. R., Makiya, Ryu, Nagashima, Masahiro, Okamoto, Takashi, Oogi, Taira, Shirakata, Hikari   +7 more
core   +1 more source

COOL-LAMPS. Discovery of COOL J0335−1927, a Gravitationally Lensed Quasar at z = 3.27 with an Image Separation of 23.″3

The Astrophysical Journal Letters, 2023
We report the discovery of COOL J0335−1927, a quasar at z = 3.27 lensed into three images with a maximum separation of 23.″3 by a galaxy cluster at z = 0.4178. To date, this is the highest redshift wide-separation lensed quasar known.
Kate Napier, Michael D. Gladders, Keren Sharon, Håkon Dahle, Aidan P. Cloonan, Guillaume Mahler, Isaiah Escapa, Josh Garza, Andrew Kisare, Natalie Malagon, Simon Mork, Kunwanhui Niu, Riley Rosener, Jamar Sullivan Jr., Marie Tagliavia, Marcos Tamargo-Arizmendi, Raul Teixeira, Kabelo Tsiane, Grace Wagner, Yunchong Zhang, Megan Zhao   +20 more
doaj   +1 more source

Modeling the HeII Transverse Proximity Effect: Constraints on Quasar Lifetime and Obscuration

, 2017
The HeII transverse proximity effect - enhanced HeII Ly{\alpha} transmission in a background sightline caused by the ionizing radiation of a foreground quasar - offers a unique opportunity to probe the emission properties of quasars, in particular the ...
Davies, Frederick B., Hennawi, Joseph F., Lukić, Zarija, Oñorbe, Jose, Schmidt, Tobias M., Worseck, Gábor   +5 more
core   +1 more source

Monitoring and quantifying of water turbidity in the Albufera of Valencia during the 2024 flood using a machine learning model

Cuadernos de Geografía de la Universitat de València
Monitoring turbidity during flood events is vital for assessing the extent of water contamination, understanding sediment transport dynamics, and guiding emergency response efforts to mitigate ecological damage and health risks. In this study, we aim to
Masuma Chowdhury, Ana Belén Ruescas Orient, Ignacio De la Calle, Irene Laiz   +3 more
doaj   +1 more source