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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 utilization of seismic barriers for protection against the hazardous impact of natural or technogenic waves is an extremely promising emerging technology to secure buildings, structures and entire areas against earthquake-generated seismic waves, high-speed-transport-induced vibrations, etc. The current research is targeted at studying the effect of seismic-barrier shape on the reduction of seismic-wave magnitudes within the protected region. The analytical solution of Lamb's problem was used to verify the adopted numerical approach. It was demonstrated that the addition of complementary geometric features to a simple barrier shape provides the possibility of significantly increasing the resulting seismic protection. A simple genetic algorithm was employed to evaluate the nontrivial but extremely effective geometry of the seismic barrier. The developed approach can be used in various problems requiring optimization of non-parameterizable geometric shapes. The applicability of genetic algorithms and other generative algorithms to discover optimal (or close to optimal) geometric configurations for the essentially multiscale problems of the interaction of mechanical waves with inclusions is discussed. [ABSTRACT FROM AUTHOR]

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.

A comparative study of the vertical seismic barriers intended for protecting from Rayleigh seismic waves and filled with (1) homogeneous linearly elastic materials and (2) granular metamaterials, is done by the finite-element (FE) modeling. The granular metamaterial obeys the Mohr–Coulomb plasticity model with the associated flow rule, low cohesion value, and small internal friction and dilation angles. The performed numerical analysis reveals a principal ability achieving much higher reduction ratios for magnitudes of accelerations along with much longer shadow zones behind the barrier for barriers filled with metamaterials in comparison with the purely elastic homogeneous barriers. [ABSTRACT FROM AUTHOR]

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.

This paper investigates the microstructural evolution and grain refinement kinetics of a solution-treated Cu-0.1Cr-0.06Zr alloy during equal channel angular pressing (ECAP) at a temperature of 673 K via route BC. The microstructural change during plastic deformation was accompanied by the formation of the microband and an increase in the misorientations of strain-induced subboundaries. We argue that continuous dynamic recrystallization refined the initially coarse grains and discuss the dynamic recrystallization kinetics in terms of grain/subgrain boundary triple junction evolution. A modified Johnson-Mehl-Avrami-Kolmogorov relationship with a strain exponent of about 1.49 is used to express the strain dependence of the triple junctions of high-angle boundaries. Severe plastic deformation by ECAP led to substantial strengthening of the Cu-0.1Cr-0.06Zr alloy. The yield strength increased from 60 MPa in the initial state to 445 MPa after a total strain level of 12. [ABSTRACT FROM AUTHOR]