 In this article, we explore this class of model and prove several theoretical results based on the framework developed in [ 17 ], of which the present work is a companion paper.
<meaning-changed>  In this article, we explore this class of model and prove several theoretical results based on the framework developed in [ 17 ], of which the present work is a companion paper.
 In this article, we explore this class of model and prove several theoretical results based on the framework developed in [ 15 ], of which the present work is a companion paper.