Figure 2
The graph is titled “Illustrative Degradation Trajectories for Extended Kinetic Formulations”. The horizontal axis is labeled “Operational Time”, ranging from 0 to 140 with an interval of 20, and the vertical axis is labeled “Normalized Degradation State”, ranging from 0 to 1.0 with an interval of 0.2. Three curves are plotted and identified in a legend at the lower right: a blue line labeled “First-Order Kinetics”, an orange line labeled “Nonlinear Saturation Extension”, and a green line labeled “Two-State Lifecycle Model”. All three curves start at (0, 0.0) and increase over time. The orange curve rises most rapidly, reaching near saturation close to 1.0 by around time 85 and flattening thereafter. The blue curve increases more gradually and reaches (140, 0.96). The green curve shows the slowest growth, rising steadily, and reaching (140, 0.83). Note: All numerical data values are approximated.Illustrative degradation trajectories for extended kinetic formulations. Comparison between classical first-order irreversible kinetics, a nonlinear saturation model incorporating wear-out acceleration, and a two-state lifecycle formulation. All models preserve monotonic and bounded evolution of the normalized degradation state, demonstrating the structural extensibility of the proposed physics-informed digital twin framework