Royal Thai NavyA Network Flow Viewpoint to

Offshore Patrol Vessel Engineering

CDR Peerapong Yoosiri, Royal Thai Navy LT Jeff Lineberry, United States Navy

Agenda

• Background• Network Model• Method• Formulation• Results• Analysis• Conclusions

Background

Background

Background

• 6 OPVs are required according to strategy plan

• 2 OPVs ,constructed in China, have been commissioned in the fleet

• RTN is currently building a ship by domestic dockyard.

• Planning to have 3 more OPVs in the future.

http://www.baesystems.com/Businesses/SurfaceShips/PlatformsandProgrammes/OffshorePatrolVessels/index.htm

Problem Statement

“Roughly forty percent of material and parts are acquired from domestic contractors, leaving the dependency on a multitude of procurement from other countries.”

Assumptions

Many of the smaller and further contractors will have more cost associated with them but may serve as good alternatives when some of the major procurement nodes are eliminated.

Data Sources

All nodes and arc data was acquired from representatives of RTN.

Network Model

@ = Start of ProjectA = Sign ContractB = Jig ConstructionC = Pre-Fab & Sub-BlockD = Composing StructureE = ReleaseF = Propulsion PlantG = Cable TrayH = Electric PlantI = PipingJ = Assistant Engine

K = Main EngineL = Electronic SystemM = Communication SystemO = Decoration SystemP = Quality ControlQ = Command & Control SystemR = 76 mm. Gun SystemS = 30 mm. Gun SystemT = HATU = SATV = Delivery$ = End of Project

Methodology

Formulation

𝑍=∑(𝑖 , 𝑗 )

(𝑐 𝑖𝑗+𝑑𝑒𝑙𝑎𝑦∗𝑥𝑏𝑎𝑟 (𝑖 , 𝑗 ) )∗ 𝑦 𝑖𝑗

∑𝑖𝑗

𝑦 𝑖𝑗−∑𝑗𝑖

𝑦 𝑗𝑖={−1 𝑖𝑓 𝑗 𝑖𝑠 𝑠𝑡𝑎𝑟𝑡1 𝑖𝑓 𝑗 𝑖𝑠 𝑑𝑜𝑛𝑒0 h𝑜𝑡 𝑒𝑟𝑤𝑖𝑠𝑒

Results

• We convert 22 nodes into 46 nodes by looking at contract

options.

• Most contractors save money on job completion.

• Running shortest path interdictions, we were able to find the 8

contractors which represent 4 of the 10 countries we looked at.

• Utilizing those contractors, we save cost from the proposed $

91.7 M.

Analysis

Analysis

To make this problem more realistic, we manipulate the GAMS code by only interdicting the countries that associated with contractors.

Only 4 countries from the shortest path model could be affected by this scenario unless we had interdicted more than one countries.

Analysis

Conclusion

Question?