Disappearing labels could soon tell you when food in your fridge is out of date. The National Taiwan University in Taipei has developed an ink based on anthraquinone 尾-sulfonate, which fades from red to beige in the presence of oxygen. Varying the thickness of a gas-permeable polyacrylate film on top of a food label allows different sell-by dates to be 鈥減rogrammed鈥� ().
Touching frequently used biometric scanners can be unhygienic. So engineers from Malaysia and South Korea have written software that allows a webcam to snap and identify a palm-print without physical contact. Hand-tracking software focuses on the regions of interest and a neural network learns the salient features of each user鈥檚 palm (Image and Vision Computing, ).
