The official list of competitors for the ISU World Figure Skating Championships lists Liu as a "substituted" skater.

Abstract: Analytical expression of transmission for the orbital angular momentum (OAM) communication using loop antenna arrays and paraboloids is derived to achieve a communication distance of 100 m.

Refilling a bottle instead of throwing it away has become a popular way for people to reduce waste — a small, tangible action ...

Abstract: Indoor magnetic fields are a combination of Earth's magnetic field and disruptions induced by ferromag-netic objects, such as steel structural components in buildings. As a result of these ...