Abstract: A warning device and a mobile carrier assembly are provided. The mobile carrier assembly includes a mobile carrier and a warning device mounted at the outside of the mobile carrier. The warning device includes an energy harvesting unit, a battery, an object sensor and a warning element. The energy harvesting unit is used to retrieve an energy from an environment and convert the energy into an electrical energy. The battery is electrically connected with the energy harvesting unit for storing the electrical energy. The object sensor is electrically connected with the battery and used to sense whether an object is present in a predetermined range. The warning element is electrically connected with the object sensor and used to issue an alert when the object sensor senses that an object is present in the predetermined range. The alert includes a sound or light.

Abstract: A data transfer method for a wireless access point with a Multi-User Multiple-Input Multiple-Output (MU-MIMO) function is disclosed. The data transfer method includes: receiving support function information and a data transfer request from each of electronic devices; determining whether each of the electronic devices supports MU-MIMO function according to the support function information; dividing the electronic devices into a first group supporting the MU-MIMO function and a second group without supporting the MU-MIMO function; allocating a first transferring time frame to the first group and allocating a second transferring time frame to the second group according to the data transfer requests; transferring data requested by the first group within the first transferring time frame via the MU-MIMO function; transferring data requested by the second group within the second transferring time frame.