Update research.md

Author: oferdagan

_includes/research.md

@@ -28,7 +28,7 @@ $$
 \end{aligned}
 $$
 
-Here $$X_{ijt}$$ is a binary 3-dimensional control variable representing whether or not observer $$j$$ observers object $$i$$ at time step $$t$$, and $$O_{ijt}$$ represents whether or not observer $$j$$ *is able to* observe object $i$ at time $$t$$.
+Here $$X_{ijt}$$ is a binary 3-dimensional control variable representing whether or not observer $$j$$ observers object $$i$$ at time step $$t$$, and $$O_{ijt}$$ represents whether or not observer $$j$$ *is able to* observe object $$i$$ at time $$t$$.
 
 For ground based-sensors, the ILP plan can be visualized as follows:
 ![ILP-Plan](../assets/images/ilp-plan-600.gif)