. ▁ ▁While ▁the ▁first ▁D P ▁ships ▁had ▁analog ue ▁controllers ▁and ▁lack ed ▁redund ancy , ▁since ▁then ▁vast ▁improvements ▁have ▁been ▁made . ▁Besides ▁that , ▁D P ▁now ad ays ▁is ▁not ▁only ▁used ▁in ▁the ▁oil ▁industry , ▁but ▁also ▁on ▁various ▁other ▁types ▁of ▁ships . ▁In ▁addition , ▁D P ▁is ▁not ▁limited ▁to ▁maintain ing ▁a ▁fixed ▁position ▁any ▁more . ▁One ▁of ▁the ▁possibilities ▁is ▁sail ing ▁an ▁exact ▁track , ▁useful ▁for ▁cable lay , ▁pip el ay , ▁survey ▁and ▁other ▁tasks . ▁ ▁Com parison ▁between ▁position - keep ing ▁options ▁Other ▁methods ▁of ▁position - keep ing ▁are ▁the ▁use ▁of ▁an ▁anchor ▁spread ▁and ▁the ▁use ▁of ▁a ▁jack - up ▁bar ge . ▁All ▁have ▁their ▁own ▁advantages ▁and ▁dis adv antages . ▁ ▁Although ▁all ▁methods ▁have ▁their ▁own ▁advantages , ▁dynamic ▁position ing ▁has ▁made ▁many ▁operations ▁possible ▁that ▁were ▁not ▁feas ible ▁before . ▁ ▁The ▁costs ▁are ▁falling ▁due ▁to ▁newer ▁and ▁che aper ▁techn ologies , ▁and ▁the ▁advantages ▁are ▁becoming ▁more ▁comp elling ▁as ▁off sh ore ▁work ▁enters ▁ever ▁deeper ▁water ▁and ▁the ▁environment ▁( cor al ) ▁is ▁given ▁more ▁respect . ▁With ▁container ▁operations , ▁crow ded ▁ports ▁can ▁be ▁made ▁more ▁efficient ▁by ▁quick er ▁and ▁more ▁accurate ▁ber thing ▁techniques . ▁Cru ise ▁ship ▁operations ▁benefit ▁from ▁faster ▁ber thing ▁and ▁non - anch ored ▁" mo or ings " ▁off ▁be aches ▁or ▁in access ible