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We have developed a real-time moment tensor monitoring system (RMT) which takes advantage of a grid-based moment tensor inversion technique and real-time broad-band seismic recordings to automatically monitor earthquake activities in the vicinity of Taiwan. The centroid moment tensor (CMT) inversion technique and a grid search scheme are applied to obtain the information of earthquake source parameters, including the event origin time, hypocentral location, moment magnitude and focal mechanism. All of these source parameters can be determined simultaneously within 117 s after the occurrence of an earthquake. The monitoring area involves the entire Taiwan Island and the offshore region, which covers the area of 119.3°E to 123.0°E and 21.0°N to 26.0°N, with a depth from 6 to 136 km. A 3-D grid system is implemented in the monitoring area with a uniform horizontal interval of 0.1° and a vertical interval of 10 km. The inversion procedure is based on a 1-D Green's function database calculated by the frequency–wavenumber (fk) method. We compare our results with the Central Weather Bureau (CWB) catalogue data for earthquakes occurred between 2010 and 2012. The average differences between event origin time and hypocentral location are less than 2 s and 10 km, respectively. The focal mechanisms determined by RMT are also comparable with the Broadband Array in Taiwan for Seismology (BATS) CMT solutions. These results indicate that the RMT system is realizable and efficient to monitor local seismic activities. In addition, the time needed to obtain all the point source parameters is reduced substantially compared to routine earthquake reports. By connecting RMT with a real-time online earthquake simulation (ROS) system, all the source parameters will be forwarded to the ROS to make the real-time earthquake simulation feasible. The RMT has operated offline (2010–2011) and online (since January 2012 to present) at the Institute of Earth Sciences (IES), Academia Sinica (http://rmt.earth.sinica.edu.tw). The long-term goal of this system is to provide real-time source information for rapid seismic hazard assessment during large earthquakes. [ABSTRACT FROM AUTHOR]

In this paper, we estimate the effect of random work function (WK) on the threshold voltage fluctuation (\sigma Vth) of 16-nm-gate metal-oxide-semiconductor field-effect transistors (MOSFETs) with metal-gate materials. To examine the random WK induced \sigma Vth, nanosized metal grains with different gate materials are considered in a large-scale statistical simulation. An analytical expression of the WK induced \sigma Vth is proposed based on the Monte Carlo simulation results which can outlook different extents of fluctuation resulting from various metal gates and benefit the device fabrication. Devices with a two-layer metal-gate are further studied for fluctuation suppression; the finding of this paper indicates the first layer of the gate structure plays the most significant role in the suppression of the WK induced \sigma Vth, compared with the second layer. This paper provides an insight into random work-function-induced threshold voltage fluctuation, which can, in turn, be used to assess metal gate characteristics of MOSFETs. [ABSTRACT FROM PUBLISHER]