The investigation described in this paper aims to determine the factors in the deterioration of reinforced concrete (RC) bridge deck slab components, quantitatively evaluate them using survival analysis, and thus facilitate optimal decision-making. To consider bridge deterioration across Japan, bridge inspection data from the East Japan and Tokyo regions were selected based on their different deterioration phenomena and processes. Data cleaning and selection were conducted to increase the accuracy and reliability of the analysis. Using the Kaplan–Meier (KM) estimator and Cox multivariate regression model, the hazard risk of each variate was quantitatively estimated. For East Japan, winter precipitation and de-icing salt greatly increased the deterioration rate, indicating that high humidity and a high salinity environment were the main reasons for deterioration. However, for the Tokyo region, traffic loading resulted in high risk, indicating that fatigue failure was the main risk factor. In both areas, the slab edge showed a high deterioration rate; therefore, edge waterproofing should be improved to enhance durability. Additionally, the risk score of each bridge component was calculated and mapped using geographical coordinate information. Inspection, repairs, and rehabilitation can be more efficiently conducted using this information.

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In order to accurately emulate the operation conditions of high-speed motorized spindle in the reliability experiment, a dynamic loading system is proposed. This system allows simultaneously loading torque, radial and axial force against the spindle. The torque load is carried out by the electric dynamometer; the non-contact vibration exciter completes the radial load; the axial load is carried out by a self-made electromagnet. Moreover, this system also can detect out the basic features and failure data of the motorized spindle during the loading. And these sampling data provide a quantitative elevation for its reliability analysis. This paper presents a simple solution to the high-speed motorized spindle reliability research where the loading experiment is designed with the spindle whose maximum rotational speed is 18000rpm.

The precision of the weak equivalence principle (WEP) test using atom interferometers (AIs) is expected to be extremely high in microgravity environment. The microgravity scientific laboratory cabinet (MSLC) in the China Space Station (CSS) can provide a higher-level microgravity than the CSS itself, which provides a good experimental environment for scientific experiments that require high microgravity. We designed and realized a payload of a dual-species cold rubidium atom interferometer. The payload is highly integrated and has a size of $$460\,{\rm{mm}}\times 330\,{\rm{mm}}\times 260\,{\rm{mm}}$$ 460 mm × 330 mm × 260 mm . It will be installed in the MSLC to carry out high-precision WEP test experiment. In this article, we introduce the constraints and guidelines of the payload design, the compositions and functions of the scientific payload, the expected test precision in space, and some results of the ground test experiments.