Alkali metal Na is beneficial to the performance of CuInGaSSe thin film solar cells. This work studies the addition and optimization of a sputtering SiO 2 barrier layer on the SLG to optimize the Na content that diffuses into the absorber layer from the SLG. The resulting Se content and...

This paper studies the estimation of a semi-strong GARCH(1,1) model when it does not have a stationary solution, where semi-strong means that we do not require the errors to be independent over time. We establish necessary and su±cient conditions for a semi-strong GARCH(1,1) process to have a...

Longitudinal studies are often conducted to explore the cohort and age effects in many scientific areas. The within cluster correlation structure plays a very important role in longitudinal data analysis. This is because not only can an estimator be improved by incorporating the within cluster...

Longitudinal studies are often conducted to explore the cohort and age effects in many scientific areas. The within cluster correlation structure plays a very important role in longitudinal data analysis. This is because not only can an estimator be improved by incorporating the within cluster...