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This article aims to predict the rapid track geometry change in the short term with a higher detection frequency, and realize the monitoring and maintenance of the railway state.

Firstly, the ABA data needs to be filtered to remove the DC component to reduce the drift due to integration. Secondly, the quadratic integration in frequency domain for concern components of the vertical and lateral ABA needs to be done. Thirdly, the displacement in lateral of the wheelset to rail needs to be calculated. Then the track alignment irregularity needs to be calculated by the integration of lateral ABA and the lateral displacement of the wheelset to rail.

By comparing with a commercial track geometry measurement system, the high-speed railway application results in different conditions, after removal of the influence of LDWR, identified that the proposed method can produce a satisfactory result.

This article helps realize detection of track irregularity on operating vehicle, reduce equipment production, installation and maintenance costs and improve detection density.

Radial vibration of horizontal centrifugal pump has a close association with radial exciting forces. The purpose of this paper is to analyze the unsteady radial force in multistage centrifugal pump with double volute in detail and investigate the relevance of static pressure, radial force and radial vibration.

The unsteady numerical simulation with realizable k-ε turbulence model was carried out for a multistage centrifugal pump with double volute using computational fluid dynamics codes Fluent. The performance tests were conducted by use of a closed loop system and performance curves from numerical simulation agree with that of experiment. Vibration tests were carried out by vibration probes instrumented on the bearing cover of pump near no-driven end. Fast Fourier transform was used to obtain the frequency components of radial forces on the impellers from numerical simulation, which are compared with ones of radial vibration from experiment in Y and Z direction. And the static pressure distributions in the impeller were analyzed under different flow rates.

The symmetrical double volute can effectively balance radial forces. The maximum radial force and vibration velocity appear at 0.6 Q among the three flow rates 0.6 Q, Q and 1.2 Q. The frequencies corresponding to relatively large amplitude of vibration velocities and radial forces on the impellers in Y direction are blade passing frequency of the impellers. Blade passing frequency of first-stage impeller and shaft frequency are predominating in Z direction. It indicates that the radial vibration of centrifugal pump is closely related to the unsteady radial force.

The unsteady radial forces of the impeller in multistage centrifugal pump with double volute were comprehensively analyzed. The radial forces should be considered to balance during the design of multistage centrifugal pump.

The aim of this paper is to argue for the values of familial caring and relationships in addition to the provision of social media technology during the COVID-19 pandemic in Hong Kong.

The discussion of this paper has adopted an inter-disciplinary approach by integrating health care system and psychological analysis, based on cultural philosophical argument through the hermeneutic approach of classical texts and critical analysis.

The COVID-19 pandemic has exposed the dilemma between the public health measures for COVID-19 and sustaining elderly social psychological health through familial connection. From a Confucian perspective, the practice of filial piety (xiao, 孝), which demands taking care of parents, is essential for one’s moral formation, and for one’s becoming a virtuous (ren, 仁) person. The necessity of taking care of elderly parents by adult children is not something that can be explained in terms of consequentialism. Indeed, the rising trend of instrumental rationality seems to weaken rather than strengthen the sense of filial obligation. In the face of the COVID-19 pandemic which tends to separate connections between family members, the author argues that we should emphasize the values of familial caring and relationship because it enhances the elderly’s characteristic of resilience.

This paper shows that while social media technology has mitigated the negative effect of social distancing, such online relationships should never replace the bodily connections between the elderly and their family members from a Confucian perspective.