With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Yung Rich Nation featured Chris Brown.
text_B: In scientific visualization a streamlet is used to visualize flows .. scientific visualization. scientific visualization. It is essentially a short streamline segment .. streamline. Streamlines, streaklines, and pathlines. Normally the length of a streamlet is proportional to the flow magnitude at its seed point .. Category  : Fluid dynamics
not_related.