[1] Relaxed sound speed measurements on 12 liquids in the CaO-MgO-Al 2 O 3 -SiO 2 (CMAS) system have been performed from 1410 to 1620°C at 1 bar with a frequency sweep acoustic interferometer. In all liquids, the sound speeds either decrease or remain constant with increasing temperature. These data are combined with those in the literature to calibrate models for b T and (@V/@P) T as a function of composition and temperature for CMAS liquids. CaO is the only oxide component that contributes to the temperature dependence of compressibility. The new compressibility models permit the bulk modulus (K T,0 ) of CaMgSi 2 O 6 (Di), CaAl 2 Si 2 O 8 (An), and the Di 64 -An 36 eutectic liquid to be directly obtained. These results are used to uniquely constrain values for the pressure dependence of the bulk modulus (K 0 0 = dK 0 /dP) in a third-order Birch-Murnaghan equation of state (EOS) for these three liquids from shock wave data in the literature. The revised K 0 0 value is 6.8 (versus 6.9) for CaMgSi 2 O 6 liquid, 4.7 (versus 5.3) for CaAl 2 Si 2 O 8 liquid, and 5.6 (versus 4.85) for Di 64 -An 36 liquid. Information on both K T,0 and K 0 0 allows the density and compressibility for each of these three liquids to be calculated as a function of pressure to 25 GPa. Both the molar volume and isothermal compressibility of CaMgSi 2 O 6 -CaAl 2 Si 2 O 8 liquids mix ideally between 0 and 25 GPa. The dominant mechanism of compression at low pressure (0-5 GPa) for all three liquids (CaMgSi 2 O 6 , CaAl 2 Si 2 O 8 , and the Di 64 -An 36 eutectic) is topological, whereas gradual Al/Si coordination change plays an increasingly important role at higher pressure as topological mechanisms of compression are diminished.

Intelligent vehicles and advanced driver assistance systems (ADAS) need to have proper awareness of the traffic context as well as the driver status since ADAS share the vehicle control authorities with the human driver. This study provides an overview of the ego-vehicle driver intention inference (DII), which mainly focus on the lane change intention on highways. First, a human intention mechanism is discussed in the beginning to gain an overall understanding of the driver intention. Next, the ego-vehicle driver intention is classified into different categories based on various criteria. A complete DII system can be separated into different modules, which consists of traffic context awareness, driver states monitoring, and the vehicle dynamic measurement module. The relationship between these modules and the corresponding impacts on the DII are analyzed. Then, the lane change intention inference (LCII) system is reviewed from the perspective of input signals, algorithms, and evaluation. Finally, future concerns and emerging trends in this area are highlighted.

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A self-driven closed-loop parallel testing system implements more challenging tests to accelerate evaluation and development of autonomous vehicles.

[1] A general acoustic model for a frequency sweep rod-liquid-rod interferometer applicable to high-temperature silicate liquids is presented. The wave propagations in the acoustic model are solved according to the accurate elastic wave equation and the acoustic wave equation. The solutions indicate that when a pulsed wave is sent down a buffer rod, which is partially immersed in a silicate liquid, the return signal consists of a series of plane waves (mirror reflections from the liquid) and two series of interfering pulses (modes A and B), which are propagating disturbances guided by the cylindrical surface of the upper rod. The acoustic model gives mathematical expressions for the time delays between the various interfering pulses and between the mirror reflections, which are predicted to vary according to the material and dimensions of the upper buffer rod and liquid. These predictions are verified by experiments on molybdenum and aluminum rods of varying dimensions in air, water, and silicate liquid. These results demonstrate that mirror reflections from the liquid can be isolated from the interfering pulses in the return signal by appropriate choice of the dimensions and material of the upper rod. This theoretical model provides a critical foundation for construction of an acoustic interferometer that is uniquely able to measure relaxed sound speeds in silicate liquids at high temperature and high pressure by the frequency sweep method.

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