In the figure, {HEAD ~ the electronic components} 17 to be treated at {TAIL ~ each work process} are indicated with the solid black boxes for the viewing convenience 
to be treated at
In the figure , { HEAD ~ the electronic components } 17 to be treated at { TAIL ~ each work process } are indicated with the solid black boxes for the viewing convenience
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH