1,045 research outputs found
Using simulated Tianqin gravitational wave data and electromagnetic wave data to study the coincidence problem and Hubble tension problem
In this paper, we use electromagnetic wave data (H0LiCOW, , SNe) and
gravitational wave data (Tianqin) to constrain the interacting dark energy
(IDE) model and investigate the Hubble tension problem and coincidences
problem. By combining these four kinds of data (Tianqin+H0LiCOW+SNe+), we
obtained the parameter values at the confidence interval of :
, ,
, and . According
to our results, the best valve of show that the Hubble tension problem
can be alleviated to some extent. In addition, the of which the center value indicates the
coincidence problem is slightly alleviated. However, the is
still within the error range which indicates the CDM model
is still the model which is in best agreement with the observational data at
present. Finally, we compare the constraint results of electromagnetic wave and
gravitational wave on the model parameters and find that the constraint effect
of electromagnetic wave data on model parameters is better than that of
simulated Tianqin gravitational wave data.Comment: The article has been accepted by Chinese Physics
Cooperative inter-vehicle communication protocol with low cost differential GPS
This paper describes a cooperative MANET protocol dedicated to intelligent transport systems, named CIVIC (Communication Inter Véhicule Intelligente et Coopérative). The CIVIC protocol is an auto-configuration inter-vehicle communication protocol, which supports adhoc and infrastructure networks, contains reactive and proactive routing components, and adapts different wireless standards. It is a context-aware protocol reacting to vehicle status, road traffic, and geographic environment. It supports location-based communication. To improve the accuracy of GPS, it integrates a localization solution called LCD-GPS (Low Cost Differential GPS). It has been implemented and experimented on the LiveNode sensor developed by our lab. At the end of this paper, an application project MobiPlus is introduced
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