No abstract

As more and more Commercial Off The Shelf (COTS) parts are being used in sustainment-dominated systems where average product lifecycle is above 25 years, obsolescence management becomes a greater concern for program managers. The lack of management and poor planning for obsolescence cause companies, governments, and military organizations to spend progressively more to deal with aging systems. For a successful obsolescence management, program managers should consider both the cost-effectiveness and system availability issues simultaneously and should implement appropriate solution approaches. In this chapter, the authors first define the obsolescence management in sustainment-dominated systems and then give a brief summary of the related literature. They finally discuss and propose multiple criteria decision-making methodologies and evolutionary algorithms to tackle the management problem.

The purpose of this study is to provide program managers and systems engineers with a novel algorithm in determining the design refresh time (DRT) of sustainmentdominated systems due to COTS obsolescence. Most of the research done so far has focused on cost optimization. The main contribution of the study is two-fold. First, besides cost optimization, we have introduced efficiency optimization within a balanced approach to determine the DRT, under multiple objectives. Second, we used a set-based approach over the hypervolume quality values of solutions rather than population-based Pareto solutions. We proposed a discrete-time simulation model by using Multi-Objective Evolutionary Algorithms where the deterioration over the quality values of Pareto solution sets is used as an indicator for a DRT. We supported the proposed mathematical model in theory with empirical findings from a case study for a sustainment-dominated Naval Command and Control System that was designed in 2004 and deployed in 2007. We ran the simulation as for 2007 and conducted an analysis over the cost and operational efficiency objectives to compare the situation experienced in real life against the simulation outputs of the proposed model. The results revealed that not only the total life cycle cost but also efficient operational sustainability of a system would be increased significantly if the system had gone through design refreshes as proposed by the model. We showed that the deterioration of the Pareto optimal solutions' hypervolume quality values over time is an effective marker to decide the optimal DRT under conflicting multiple objectives.

As more and more Commercial Off The Shelf (COTS) parts are being used in sustainment-dominated systems where average product lifecycle is above 25 years, obsolescence management becomes a greater concern for program managers. The lack of management and poor planning for obsolescence cause companies, governments, and military organizations to spend progressively more to deal with aging systems. For a successful obsolescence management, program managers should consider both the cost-effectiveness and system availability issues simultaneously and should implement appropriate solution approaches. In this chapter, the authors first define the obsolescence management in sustainment-dominated systems and then give a brief summary of the related literature. They finally discuss and propose multiple criteria decision-making methodologies and evolutionary algorithms to tackle the management problem.