Before revision:  In this paper, the trust-region-reflective (TTR) algorithm is used to fit the model to estimate both time-invariant and time-varying (with bounded contsraints) parameters. The model is verified using a case study based on the data in Kazakhstan, which is a country badly affected by this pandemic but has not been receiving much attention by the research community thus far . Finally, some forecasts are made using five scenarios with time-dependent control measures such that the effects of the control actions onto the transmission dynamics of the pandemic can be quantified and betterunderstood .
After revision:  In this paper, the model is verified using a case study based on the data in Kazakhstan, which is a country badly affected by this pandemic but has not been receiving much attention by the research community thus far . Finally, some forecasts are made using five scenarios with time-dependent control measures such that the effects of the control actions onto the transmission dynamics of the pandemic can be quantified and betterunderstood .