Not only is it important to know how large the overall change in vibration should be for occupants to perceive an improvement in comfort, but also how large this change should be in specific frequency bands. Relative difference thresholds (RDT) of primary (0.5-4 Hz) and secondary (9-80 Hz) ride are estimated for 14 automotive engineers seated in a vehicle on a 4-poster test rig over two roads.
View Article and Find Full Text PDFThis study aims to enhance the energy use of two products of industry - Queen Palm residue and kraft lignin (KF) - through the combination of two technologies - briquetting and slow pyrolysis. The addition of 20% KF provided briquettes with higher physical, energy, and mechanical properties. The yields of the pyrolysis products were affected by both the pyrolysis temperature and the addition of KF.
View Article and Find Full Text PDFLow-elevation regions harbour the majority of the world's species diversity compared to high-elevation areas. This global gradient suggests that lowland species have had more time to diversify, or that net diversification rates have been higher in the lowlands. However, highlands seem to be cradles of diversity as they contain many young endemics, suggesting that their rates of speciation are exceptionally fast.
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