Results 21 to 30 of about 2,013 (259)

Retrieval of the Stratospheric Density by the Star Occultation

Aerospace, 2023
The navigation by the stellar refraction is important for a LEO (Low-Earth-Orbit) satellite, especially in a GNSS (Global Navigation Satellite System)-denied environment, since it is totally autonomous.
Kedong Wang, Zhennan Li, Shaoxiong Zhang
doaj   +1 more source

The colibri telescope array for KBO detection through serendipitous stellar occultations: A technical description

Frontiers in Astronomy and Space Sciences, 2022
We present the technical design, construction and testing of the Colibri telescope array at Elginfield Observatory near London, Ontario, Canada. Three 50-cm telescopes are arranged in a triangular array and are separated by 110–160 m.
Michael J. Mazur, Stanimir Metchev, Stanimir Metchev, Rachel A. Brown, Rachel A. Brown, Ridhee Gupta, Richard Bloch, Tristan Mills, Emily Pass   +8 more
doaj   +1 more source

Evaluating the effect of four unknown parameters included in a latitudinal energy balance model on the habitability of exoplanets

Open Astronomy, 2020
Among different models for determining the habitable zone (HZ) around a star, a Latitudinal Energy Balance Model (LEBM) is very beneficial due to its parametricity which keeps a good balance between complexity and simulation time.
Bahraminasr Majid, Jafarzadeh S. Javad, Montazeri Fatemeh, Poro Atila, Sarabi Soroush   +4 more
doaj   +1 more source

Manuels scolaires d’éducation à la citoyenneté au collège et problématique du développement durable, pour une analyse du curriculum prescrit d’instruction civique au Gabon [PDF]

Akofena, 2022
Résumé : La présente contribution se donne pour objectif d’interroger l’éducation à la citoyenneté au collège dans les établissements d’enseignement secondaire public.
Orphée Martial SOUMAHO MAVIOGA & Dany Daniel BEKALE
doaj  

Design and Simulation of Stellar Occultation Infrared Band Constellation

Remote Sensing, 2022
This study provides an in-depth analysis of the characteristics of stellar occultation events. Using 10 target star sources, the influence of orbital elements on the number, duration, and distribution of stellar occultation events was simulated and ...
Qinglin Zhu, Mingchen Sun, Xiang Dong, Pengfei Zhu   +3 more
doaj   +1 more source

Assessment of Retrieved N2O, NO2, and HF Profiles from the Atmospheric Infrared Ultraspectral Sounder Based on Simulated Spectra

Sensors, 2018
The Atmospheric Infrared Ultraspectral Sounder (AIUS), the first high-resolution (0.02 cm−1) solar occultation sounder, aboard GF5, was launched in May 2018 from China.
Hongmei Wang, Xiaoying Li, Jian Xu, Xingying Zhang, Shule Ge, Liangfu Chen, Yapeng Wang, Songyan Zhu, Jing Miao, Yidan Si   +9 more
doaj   +1 more source

Occult metastasis

Biomedicine & Pharmacotherapy, 2001
The most important factor affecting the outcome of patients with invasive cancers is whether the tumor has spread, either regionally (to regional lymph nodes) or systemically. However, a proportion of patients with no evidence of systemic dissemination will develop recurrent disease after primary 'curative' therapy.
D, Hawes, A M, Neville, R J, Cote
openaire   +2 more sources

SCIAMACHY lunar occultation water vapor measurements: retrieval and validation results [PDF]

Atmospheric Measurement Techniques, 2012
SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) lunar occultation measurements have been used to derive vertical profiles of stratospheric water vapor for the Southern Hemisphere in the near infrared (NIR) spectral range
F. Azam, K. Bramstedt, A. Rozanov, K. Weigel, H. Bovensmann, G. P. Stiller, J. P. Burrows   +6 more
doaj   +1 more source

Research on Stellar Occultation Detection with Bandpass Filtering for Oxygen Density Retrieval

Remote Sensing, 2023
Stellar occultation instruments detect the transmission of stellar spectra through the planetary atmosphere to retrieve densities of various atmospheric components.
Zheng Li, Xiaocheng Wu, Cui Tu, Xiong Hu, Zhaoai Yan, Junfeng Yang, Yanan Zhang   +6 more
doaj   +1 more source

Effects of Liquid Clouds on GPS Radio Occultation Profiles in Superrefractions

Earth and Space Science, 2019
Inversion of radio occultation (RO) measurements to atmospheric parameters in the neutral atmosphere utilizes the assumption of spherical symmetry by implementation of the Abel transform.
P. Hordyniec, R. Norman, W. Rohm, C.‐Y. Huang, J. Le Marshall   +4 more
doaj   +1 more source