Zobrazeno 1 - 10
of 34
pro vyhledávání: '"P. J. Cilliers"'
Publikováno v:
Annales Geophysicae, Vol 37, Pp 65-76 (2019)
In this paper, an empirical total electron content (TEC) model and trends in the TEC over the African low-latitude region are presented. GPS-derived TEC data from Malindi, Kenya (geographic coordinates 40.194∘ E, 2.996∘ S), and global ionosph
Externí odkaz:
https://doaj.org/article/fb43b9ce4a324a418a63008657833281
Publikováno v:
Annales Geophysicae, Vol 36, Pp 1161-1170 (2018)
In order to provide a scientific base to the NeQuick characterisation under disturbed conditions, the comparison of its performance for quiet and storm days is investigated in the southern mid-latitude. This investigation was realised using the tw
Externí odkaz:
https://doaj.org/article/2c14ad262f2f45a3aaaa2e5e5240f095
Autor:
P. Prikryl, R. Ghoddousi-Fard, L. Spogli, C. N. Mitchell, G. Li, B. Ning, P. J. Cilliers, V. Sreeja, M. Aquino, M. Terkildsen, P. T. Jayachandran, Y. Jiao, Y. T. Morton, J. M. Ruohoniemi, E. G. Thomas, Y. Zhang, A. T. Weatherwax, L. Alfonsi, G. De Franceschi, V. Romano
Publikováno v:
Annales Geophysicae, Vol 33, Pp 657-670 (2015)
During the ascending phase of solar cycle 24, a series of interplanetary coronal mass ejections (ICMEs) in the period 7–17 March 2012 caused geomagnetic storms that strongly affected high-latitude ionosphere in the Northern and Southern Hemisphe
Externí odkaz:
https://doaj.org/article/aa47805529644e56bd3e17eeb28f6244
Autor:
J. S. de Villiers, P. J. Cilliers
Publikováno v:
Annales Geophysicae, Vol 32, Pp 1263-1275 (2014)
This research focuses on the inversion of geomagnetic variation field measurement to obtain source currents in the ionosphere. During a geomagnetic disturbance, the ionospheric currents create magnetic field variations that induce geoelectric fiel
Externí odkaz:
https://doaj.org/article/1860ada75ad24720b88b7fd5578c0b63
Autor:
P. Prikryl, L. Spogli, P. T. Jayachandran, J. Kinrade, C. N. Mitchell, B. Ning, G. Li, P. J. Cilliers, M. Terkildsen, D. W. Danskin, E. Spanswick, E. Donovan, A. T. Weatherwax, W. A. Bristow, L. Alfonsi, G. De Franceschi, V. Romano, C. M. Ngwira, B. D. L. Opperman
Publikováno v:
Annales Geophysicae, Vol 29, Pp 2287-2304 (2011)
Arrays of GPS Ionospheric Scintillation and TEC Monitors (GISTMs) are used in a comparative scintillation study focusing on quasi-conjugate pairs of GPS receivers in the Arctic and Antarctic. Intense GPS phase scintillation and rapid variations in
Externí odkaz:
https://doaj.org/article/dddea0fa9523431583216e4c3785049c
Publikováno v:
Annales Geophysicae, Vol 28, Pp 1431-1439 (2010)
The development of a map of the ionosphere over South Africa is presented in this paper. The International Reference Ionosphere (IRI) model, South African Bottomside Ionospheric Model (SABIM), and measurements from ionosondes in the South African
Externí odkaz:
https://doaj.org/article/15d80e71320444178e54ce14ce268edf
Publikováno v:
Scientific Reports, Vol 13, Iss 1, Pp 1-12 (2023)
Abstract Triboelectric charge transfer is complex and depends on contact properties such as material composition and contact area, as well as environmental factors including humidity, temperature, and air pressure. Saturation surface charge density o
Externí odkaz:
https://doaj.org/article/3ee4f44b5b184bfab9f02a82e98da12b
Autor:
Paul Baki, Babatunde Rabiu, Christine Amory-Mazaudier, Rolland Fleury, Pierre J. Cilliers, Joseph Adechinan, Anas Emran, Aziza Bounhir, Claudio Cesaroni, J. Bienvenue Dinga, Patricia Doherty, Idrissa Gaye, Hassen Ghalila, Franck Grodji, John-Bosco Habarulema, Bruno Kahindo, Ayman Mahrous, Honoré Messanga, Patrick Mungufeni, Bruno Nava, Melessew Nigussie, Joseph Olwendo, Patrick Sibanda, René Tato Loua, Jean Uwamahoro, Naima Zaourar, Jean-Louis Zerbo
Publikováno v:
Atmosphere, Vol 14, Iss 12, p 1791 (2023)
Space weather science has been a growing field in Africa since 2007. This growth in infrastructure and human capital development has been accompanied by the deployment of ground-based observing infrastructure, most of which was donated by foreign ins
Externí odkaz:
https://doaj.org/article/634e3b2137724710932a909d861cdf58
Publikováno v:
Equine Veterinary Journal. 28:7-15
Summary A theoretical integrative model was developed to determine the heat balance of horses working in a given environment. This model included the following parameters: metabolic heat gain, solar heat gain, evaporative heat loss due to sweating, r
Autor:
A. Pretorius, P. J. Cilliers
Publikováno v:
Ergonomics. 50:1503-1515
The objective of this study is to develop a method for determining the mental workload imposed on train control officers that is objective and quantifiable and can stand up to the tests of validity and reliability. This technical note reports on the