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The stochastic Green's function method (SGFM), which simulates the source spectra of small earthquakes based on the ω−2 model and follows the scaling law of earthquakes to synthesize into a large earthquake, is a practical ground motion simulation method in areas lacking suitable small earthquake records. However, one of the problems in the application of the SGFM is that the source spectrum synthesized from small earthquakes shows a fall‐off in the mid‐frequency band, as the number of fault divisions of the large earthquake increases. To solve this problem, this study proposes an improved method, which introduces a correction coefficient for the source spectrum according to the ω−2 model and considers the variation of subfault rise time with the rupture process. Taking the 1994 Northridge earthquake as an example, the ground motion simulation results of the improved method are compared with observed records. The results show that only introducing the correction coefficient causes larger amplitude of simulation results than observed records. Only considering the variation of subfault rise time can improve the fall‐off problem to some extent, but the accuracy of ground motion simulation at observation points has no significant improvement. By simultaneously introducing the correction coefficient and considering the variation of subfault rise time, the simulation results are in good agreement with observed records and are able to reproduce the directivity effect at the forward observation points. Therefore, the improved SGFM proposed in this study is an effective and reliable tool for ground motion simulation. Key Points: The problem of source spectrum fall‐off for simulating ground motion using stochastic Green's method was pointed outAn improved method introducing a correction coefficient and considering the variation of subfault rise time simultaneously was proposedThe effectiveness of improved method was verified by comparison of the simulated and observed results of the 1994 Northridge earthquake [ABSTRACT FROM AUTHOR]

In this work, a novel non-thermal atmospheric-pressure microplasma array (APMPA) has been characterized. The APMPA employs 16 parallel capillaries with an inner diameter of 200 µm and arranged in a square configuration. Our measurements show that the stable plasma plumes can be generated by the APMPA and then spread along the dielectric surface. Both the power in the plasma source region and the one transferred onto the dielectric surface are calculated by plotting Lissajous figures. The power strongly depends on the applied voltage, frequency, and the distance between the nozzles and the dielectric surface. In addition, the temperature of N2 molecules in APMPA plasmas is calculated by using optical emission spectroscopy. The temporally resolved images of the APMPA plasmas show that the total emission intensities for the case of positive half-period is much higher than that of negative half-period. In order to describe the performance of the APMPA, the optical emission of the APMPA is compared with a single tube plasma jet with the same configuration and cross section area, and the result illustrates the APMPA can provide a higher density plasma and larger treatment area which may have a beneficial effect on various applications. [ABSTRACT FROM AUTHOR]

The brush-shape device mainly consisting of the well-aligned and microns-thick hollow quartz fibers can be used to generate an atmospheric and homogeneous cold plasma jet for biomedical applications. Addition of a trace amount of O2 into the feed gas greatly altered the electrical properties of the plasma jet, thus had an obvious effect on the sterilization efficiency. The uniformity of the brush-shape plasma jet along its transverse direction was well consistent with the uniform distribution of sterilization efficiency. The atmospheric He plasma jet containing 1% O2 may kill all the Candida albicans cells with a population of 105 spores within an exposure time of 180 s. Analysis indicates that both O radicals and charged species can be an important contributor in this plasma inactivation. [ABSTRACT FROM AUTHOR]

Cover: A special designed brush‐shape plasma device is reported to generate large area and uniform cold plasma at atmospheric pressure for biomedical application. The flexible device is consisting of well‐aligned and microns‐thick hollow quartz fibers. Addition of both the discharge distance and the amount of O2 into the plasma‐forming He gas greatly altered the electrical properties of the atmospheric plasma jet, thus had an obvious effects on the sterilization efficiency. The uniformity of the brush‐shape plasma jet along its transverse direction was well consistent with the uniform distribution of sterilization efficiency. Further details can be found in the article by D. Liu et.al. on page 88. [ABSTRACT FROM AUTHOR]