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The first arrival time of seismic P- and S- waves affects the determination of the beginning of an earthquake by the Earthquake Early Warning System for High-speed Rail (HSREEWs). Accordingly, we propose an approach to picking P- and S-waves arrival time for HSREEWs. This approach can treat the continuous seismic signals in real-time without prior knowledge of whether an earthquake occurs. Firstly, we replace the fixed time window of the S transform (ST) with the dynamic window of the generalized S transform (GST) to make the necessary time of signal processing more flexible. Meanwhile, the GST extends the sequential signal to the time-frequency domain (TF), and combines the TF polarization to construct four three-component polarization filters. Accordingly, the P-wave and S-wave can be separated from the seismic waveform by those filters, which effectively avoids the phenomenon that the S-wave phase is difficult to determine because of the interference of S-wave overlapping in the coda region. Secondly, based on the instantaneous frequency of seismic signal, we construct a new STA/LTA (GSPA-STA/LTA) with the characteristic function (CF) of constrained TF spectrum to pick the first arrivals of the P- and S-waves, and provide the corresponding automatic picking algorithm. Finally, we analyze 504 seismic events larger than Ms40 near the Japanese Tohoku Shinkansen to comprehensively verify the effectiveness of our approach. Since the P-wave and S-wave are first separated, the subsequent process just has to identify the first arrival times of their respective components. The approach has a good practical value in maintaining the safe operation of high-speed rail under earthquake, which meets the industry demands for speed, scale and accuracy in HSREEWs. • The proposed generalized S-transform (GST) has better time resolution and better frequency resolution. • Four three-component polarization filters are constructed for separating the P- and S-waves in time-frequency domain. • A new STA/LTA with constrained time-frequency spectrum is designed for picking the arrival times. • The proposed approach has better performance on picking the arrival times of the P- and S-waves than revised STA/LTA, VAR-AIC, PphasePicker et al. [ABSTRACT FROM AUTHOR]

• An early warning process for the rainstorm disaster is designed. • An HSR operation program with different rainstorm degrees is given out. • A data perception model of rainstorm is proposed with correction coefficients. In order to solve the safety operation problems of High-speed rail (HSR) in different areas and different sections under the rainstorm condition, an early warning process for the rainstorm disaster is designed. Furthermore, in order to control the operation risk, a HSR operation program with different rainstorm degrees is given out based on the analysis of rainstorm warning mechanism and rainstorm warning threshold in this paper. In addition, considering the reality that natural conditions vary greatly and the rainfall is very uneven, a data perception model of rainstorm (DPM) is proposed with correction coefficients for solving the calculation problem of precipitation for rainstorm warning. The DPM mainly adopts Paulhus's empirical equation and uses the linear function to improve it for calculating the precipitation, which is able to calculate the hourly precipitation in different regional environments, and also effectively evaluate the rainstorm warning level of high-speed rail in this period. It can calculate and monitor the process by big data and MATLAB. The result of case analysis shows that the DPM has good practical value for solving the safety operation problem of HSR in different areas under rainstorm environment. [ABSTRACT FROM AUTHOR]

• Urbanization increases MTC ownership ratio. • As urbanization increases, MTC ownership and income become U-shaped. • Urbanization changes the MTC ownership and income inequality U-shaped relationship. Recent empirical research found that the motorcycle-to-car (MTC) ownership ratio and economic performance have an inverse U-shaped relationship, with the MTC ownership ratio increasing at lower economic levels but decreasing after a critical threshold. This study examined the effects of income per population, relative improvements in road mobility over road accessibility (MOA) and income inequality on the MTC ownership ratio under different levels of urbanization. A panel of 53 nations from 1963 to 2013 was analyzed using fixed-effects panel linear regression. The inverse U-shaped relationship between the MTC ownership ratio and income changes to a U-shaped relationship as urbanization rises. The growing rate of the MTC ownership ratio and the turning point for the inverse U-shaped relationship between the ratio and income inequality both rise along with urbanization. The negative effect of MOA on the ownership ratio of MTC is lessened by urbanization. [ABSTRACT FROM AUTHOR]