A correction for the IRI topside electron density model based on Alouette/ISIS topside sounder data

Freeway control has been increasingly used as an innovative approach to ease traffic congestion, improve traffic safety and reduce exhaust emissions. As an important predictive model involved in freeway control, the predictive performance of METANET greatly influences the effect of freeway control. This paper focuses on modifying the METANET model by modeling the critical density. Firstly, the critical density model is deduced based on the catastrophe theory. Then, the perturbation wave and traveling wave that are obtained using the macro and micro data, respectively, have been developed to modify the above proposed critical density model. Finally, the numerical simulation is established to evaluate the effectiveness of the modified METANET model based on the field data from the realistic motorway network. The results show that overall, the predicted data from the modified METANET model are closer to the field data than those obtained from the original model.

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Calibration of atmospheric density model based on Gaussian Processes

Acta Astronautica ◽

10.1016/j.actaastro.2019.12.014 ◽

2020 ◽

Vol 168 ◽

pp. 273-281

Author(s):

Tianyu Gao ◽

Hao Peng ◽

Xiaoli Bai

Keyword(s):

Gaussian Processes ◽

Density Model ◽

Atmospheric Density ◽

Model Based

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Galactic structure and turbulence, pulsar distances, and the intergalactic medium

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312023691 ◽

2012 ◽

Vol 8 (S291) ◽

pp. 211-216 ◽

Cited By ~ 1

Author(s):

J. M. Cordes

Keyword(s):

Electron Density ◽

Intergalactic Medium ◽

Galactic Structure ◽

Density Model ◽

Radio Bursts ◽

Radio Waves ◽

Next Generation ◽

Scattering Measurements ◽

Galactic Model ◽

Multi Wavelength

AbstractThis paper summarizes how multi-wavelength measurements will be aggregated to determine Galactic structure in the interstellar medium (ISM) and produce the next-generation electron density model. Fluctuations in density and magnetic field from parsec scales down to about 1000 km cause a number of propagation effects in both radio waves and cosmic rays. Density microstructure appears to include Kolmogorov-like turbulence. The next generation electron-density model, NE2012, will include about double the number of lines of sight with dispersion and scattering measurements and it will be anchored with a much larger number of pulsar parallax distances. The foreground Galactic model is crucial for inferring similar ionized structures in the intergalactic medium (IGM) from scattering measurements on high-z objects. Intergalactic scattering is discussed with reference to distant sources of radio bursts. In particular, the cosmological radio scattering horizon is defined along with its analog for the ISM.

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