▁come ▁up ▁with ▁solutions ▁or ▁recommend ations ▁of ▁how ▁the ▁current ▁system ▁can ▁be ▁provided ▁to ▁meet ▁its ▁needs . ▁ ▁Det ail ▁design ▁and ▁development ▁This ▁stage ▁includes ▁the ▁development ▁of ▁detailed ▁designs ▁that ▁brings ▁initial ▁design ▁work ▁into ▁a ▁completed ▁form ▁of ▁specific ations . ▁This ▁work ▁includes ▁the ▁specification ▁of ▁interfaces ▁between ▁the ▁system ▁and ▁its ▁intended ▁environment ▁and ▁a ▁compreh ensive ▁evaluation ▁of ▁the ▁systems ▁log ist ical , ▁maintenance ▁and ▁support ▁requirements . ▁ ▁The ▁detail ▁design ▁and ▁development ▁is ▁responsible ▁for ▁producing ▁the ▁product , ▁process ▁and ▁material ▁specific ations ▁and ▁may ▁result ▁in ▁substantial ▁changes ▁to ▁the ▁development ▁specification . ▁ ▁Key ▁steps ▁within ▁the ▁detail ▁design ▁and ▁development ▁stage ▁include : ▁D etailed ▁design ▁D etailed ▁synth esis ▁Development ▁of ▁engineering ▁and ▁prototype ▁models ▁Re vision ▁of ▁development ▁specification ▁Product , ▁process ▁and ▁material ▁specification ▁Crit ical ▁design ▁review ▁ ▁Production ▁and ▁construction ▁During ▁the ▁production ▁and / or ▁construction ▁stage ▁the ▁product ▁is ▁built ▁or ▁assemble d ▁in ▁accord ance ▁with ▁the ▁requirements ▁specified ▁in ▁the ▁product , ▁process ▁and ▁material ▁specific ations ▁and ▁is ▁deployed ▁and ▁tested ▁within ▁the ▁oper ational ▁target ▁environment . ▁System ▁assess ments ▁are ▁conducted ▁in ▁order ▁to ▁correct ▁def ic ien cies ▁and ▁adapt ▁the ▁system ▁for ▁continued ▁improvement . ▁ ▁Key ▁steps ▁within ▁the ▁product ▁construction ▁stage ▁include : ▁Production ▁and / or ▁construction ▁of ▁system ▁components ▁Accept ance ▁testing ▁System ▁distribution ▁and ▁operation ▁Oper ational ▁testing ▁and ▁evaluation ▁System ▁assess ment ▁ ▁Util ization ▁and ▁support