A Petri net-based modelling of replacement strategies under technological obsolescence

Abstract

a b s t r a c tThe technological obsolescence of a unit is characterised by the existence of challenger units displaying identical functionalities, but with higher performances. Though this issue is commonly encountered in practice, it has received little consideration in the literature. Previous exploratory works have treated the problem of replacing old-technology items by new ones, for identical components facing a unique new generation of items. This paper aims to define, in a realistic way, possible replacement policies when several types of challenger units are available and when the performances of these newly available units improve with time.Since no fully generic model can exist in maintenance optimisation, a modular modelling of the problem, allowing easy adaptations to features corresponding to specific applications is highly desirable. This work therefore proposes a modular Petri net model for this problem, underlying a Monte Carlo (MC) estimation of the costs incurred by the different possible replacement strategies under consideration.

Industrial system knowledge formalization to aid decision making in maintenance strategies assessment

“…In that sense, current models are built directly in an executable and quantifiable format which implies numerous simplifications and assumptions leading to particular models difficult to be reused for more complex applications. Moreover, another additional scientific issue is that these models depend on the skills of the modeler, since they code the knowledge in a specific way to solve a specific problem (Clavareau and Labeau, 2009;Marseguerra and Zio, 2002). Globally, reusability is not offered and leads, for each model development, to spend a lot of time and money.…”

Maintaining a system subject to uncertain technological evolution

“…Moreover, as mentioned previously, the new technology is assumed to be more attractive than the old one (A1). This assumption that management is no longer interested in the old technology and will invest directly in new technology after its appearance on the market is also used in many references [9,14,6,7].…”

“…In this context, the problem is to determine the conditions on the set of characteristics (purchase price, reliability improvements, etc.) which lead to move from one technology to another [3,6,7].…”

“…The impact of these actions is modelled directly on the system failure rate. While Borgonovo et al [3] focus on a single component, Clavareau and Labeau [6,7] examine preventive and corrective replacement strategies of N identical components with the relevant logistic policy. Nguyen et al [17] consider a technological innovation sequence with an uncertain appearance time but with deterministic revenue and an estimated purchase price of new technology.…”

Optimal Policy for the Replacement of Industrial Systems Subject to Technological Obsolescence – Using Genetic Algorithm

“…A probability of incompatibility was accounted to deal with the fact that the on-site implementation of new-type units could turn out to be problematic, and some replacements could not be immediately successful, as operators have no experience to rapidly implement the new-technology unit. In [15], a test case was performed using Petri nets to model the different replacement strategies proposed in [10].…”