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Addressing the challenge of assessing the reliability of "Long-life, high-reliability" DC/DC analog converters in submarine observation networks and space power systems, which have limited internal observation points and insufficient valid information, and initial assessment rendered unreliable with the long-term operation of the converter. This paper proposes a novel method based on digital twin technology.The method eliminates the need for measuring internal variables, and only requires the measurement of the converter's ripple peak-to-peak. A digital Twin(DT) is constructed based on the underlying mechanism, and the parameters of the operating converter are identified through the collection of ripple peak-to-peak, which are then injected into the digital twin for dynamic tracking of the physical entity. By obtaining internal current and voltage of the DT and utilizing the Markov model, the reliability of the converter can be assessed.This method offers real-time reliability assessment without the need for additional measurement points. To validate the effectiveness of the proposed approach, a Superbuck converter is used as an example to demonstrate the high fidelity of the DT through isomorphic single-sample repeatability and isomorphic multiple-sample consistency experiments.

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In order to explore the impact of traffic environmental microvibration on buildings, this paper studies indoor vibration isolation, a method applicable to existing buildings. The vibration isolation scheme is designed based on the residential buildings adjacent to metro lines in Shanghai. By using the dynamic theory, the effective range of vibration isolation stiffness is analyzed. The effectiveness of the indoor vibration isolation method is verified through theoretical calculations and comparison of field measurements before and after isolation. A detailed numerical model is established to analyze the indoor isolation and the effect after parameter optimization from the slab thickness, filling material, and isolator stiffness. The results show that the isolation effect is proportional to the thickness of the total slab thickness of the isolation system and inversely proportional to the stiffness of the isolator. And when concrete is used as the filling material, the isolation effect is best. The isolation effect of the midspan position is better than that of the wall-floor junction. The vibration isolation effect is more obvious after the parameters are optimized. With its convenient construction technology, short cycle, and low cost, this method is worth promoting.