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The recent devastating earthquake of Mw7.8 occurred on February 6, 20223 in the Kahramanmaraş region having extreme intensity (XI) on the modified Mercalli scale (MMS) caused the death of more than 52,800 people in Turkey and Syria, as well as severe damages to the infrastructure. The appearance of an unusually strong delta-like S-wave pulse in the seismogram of the main shock and its consequences are analysed, and possible measures to mitigate the possible future high intensity earthquakes are discussed.

The basic idea of a seismic barrier is to protect an area occupied by a building or a group of buildings from seismic waves. Depending on the nature of seismic waves that are the most probable in a specific region, different kinds of seismic barriers are suggested. For example, vertical barriers resembling a wall in a soil can protect from Rayleigh and bulk waves. The FEM simulation reveals that to be effective, such a barrier should be (i) composed of layers with contrast physical properties allowing “trapping” of the wave energy inside some of the layers, and (ii) depth of the barrier should be comparable or greater than the considered seismic wavelength.

This paper presents a new detailed analysis of low-voltage differential signaling (LVDS) output buffers that are intended for use in high-speed integrated circuits. Three theoretically possible architectures of a LVDS output driver are discussed in rigorous detail, resulting in the recognition of the most power-conserving circuit configuration. An innovative realization of this identified low-power architecture is presented in this paper along with computer simulation results and test lab measurement data. The novel LVDS driver is designed using a unique hetero-junction bipolar transistor structure. Computer simulation results show total current consumption of 6.3 mA for the bipolar driver at a 1-GHz clock frequency while operating from a positive supply voltage between 1.7 and 3.3 V, as well as demonstrate full stage compliance with all the requirements of the IEEE 1596.3-1996 standard. The presented version of the buffer was utilized in a multiplexer/demultiplexer chip set that was fabricated in a modern 50-GHz-[f.sub.T] SiGe technology. Test results of the LVDS output buffer taken from five different chip samples reveal high-quality output eyes with more than 0.99 UI opening and close matching between the measured parameters and simulation results. Index Terms--Integrated circuits (ICs), low-voltage differential signaling, LVDS, output buffer, output driver, SiGe technology.