Abstract: Embodiments of the present invention are an unmanned aerial vehicle (UAV) severe low-power protection method and a UAV. The method includes: first acquiring ground environment information when the UAV is in a severe low-power protection state, and then obtaining landing safety judgment information according to the ground environment information, and further controlling a flight state of the UAV according to the landing safety judgment information to realize a safe landing of the UAV. The foregoing method reduces the probability of explosion of the UAV, avoids injury accidents, and improves flight safety when the UAV is in a severe low-power state.

Abstract: An ultra-thin narrow-bezel panel light includes a base plate and a bezel surrounding the base plate. The base plate includes a plurality of side walls and an accommodating portion between the side walls, and the height of the base plate is 18 mm˜26 mm. Each of the side walls has a connecting side and the side walls are installed and fixed on the bezel via the connecting sides thereof, such that the overall height of the panel light can be reduced to 20 mm˜28 mm. Thus, the panel light can be ultra-thin, low-cost and of narrow bezel.

Abstract: A method and an apparatus for protecting an unmanned aerial vehicle and an unmanned aerial vehicle are provided. After a positioning system of the unmanned aerial vehicle fails, a flight speed of the unmanned aerial vehicle is acquired at a time point before the positioning system fails, and then a flight state of the unmanned aerial vehicle is determined according to the flight speed, where the flight state includes a low-speed flight state and a high-speed flight state; and then a flight protection strategy of the unmanned aerial vehicle is adjusted according to the flight state. By implementing the method, after the positioning system of the unmanned aerial vehicle is in failure, explosion probability of the unmanned aerial vehicle can be reduced, and flight safety of the unmanned aerial vehicle can be improved.

Abstract: Embodiments of the present invention are a returning method, a controller, an unmanned aerial vehicle and a storage medium. The returning method includes: first obtaining a flight mode of an unmanned aerial vehicle, and determining a returning mode of the unmanned aerial vehicle according to the flight mode; then controlling, according to the returning mode, the unmanned aerial vehicle to return from a current position to a landing point, and determining, in a returning process, whether to switch the returning mode of the unmanned aerial vehicle according to a flight speed of the unmanned aerial vehicle; returning according to a switched returning mode when it is determined to switch the returning mode of the unmanned aerial vehicle; and keeping the current returning mode and returning when it is determined not to switch the returning mode of the unmanned aerial vehicle.

Abstract: Embodiments of the present invention are an unmanned aerial vehicle (UAV) severe low-power protection method and a UAV. The method includes: first acquiring ground environment information when the UAV is in a severe low-power protection state, and then obtaining landing safety judgment information according to the ground environment information, and further controlling a flight state of the UAV according to the landing safety judgment information to realize a safe landing of the UAV. The foregoing method reduces the probability of explosion of the UAV, avoids injury accidents, and improves flight safety when the UAV is in a severe low-power state.

Abstract: Embodiments of the present invention relate to an unmanned aerial vehicle protection method and apparatus and an unmanned aerial vehicle. The method includes: switching the unmanned aerial vehicle to an attitude mode after a positioning system of the unmanned aerial vehicle fails; controlling the unmanned aerial vehicle in the attitude mode and reducing a height of the unmanned aerial vehicle; and controlling the unmanned aerial vehicle to land safely when obtained ground environment information meets a preset landing condition. By adopting the foregoing method, the unmanned aerial vehicle can safely and smoothly land on the ground after a positioning sensor of the unmanned aerial vehicle fails, thereby reducing the probability of explosion of the unmanned aerial vehicle and improving the flight safety of the unmanned aerial vehicle.

Abstract: A heat transfer tube can comprise a tube body, and outer fins integrated with the tube body which are formed by allowing material on the tube body to extend along radial direction of the tube body and wind and extend around the tube outer surface in helical manner, wherein microscale channels are formed on at least one lateral surface of the outer fin.

Abstract: Heat transfer tubes for evaporators in air conditioning and refrigeration systems, each tube including: a tube body (1); outer fins (2) extending on an outer wall surface of the tube body (1) and having outer fin walls opposite to the outer fin walls of the adjacent outer fins; channels (6) located between the adjacent fins (2) so as to constitute channel chambers; fin top platforms (3) on respective tops of the outer fins (2), the fin top platforms (3) including fin top edges (3a) extending from both sides of the fin top platforms (3) so that the channel chambers form a cavity structure as a whole; channel chamber openings constituted by gaps between the adjacent fin top edges (3a) of the fin top platforms (3) of the outer fins; and lateral fins (4) arranged on portions or substantially middle portions of the outer fin walls of the outer fins (2) in a height direction of the outer fins (2) and at intervals in an spreading direction of the outer fins (2), so that the cavity structure is formed into a double c

Abstract: A heat transfer tube can comprise a tube body, and outer fins integrated with the tube body which are formed by allowing material on the tube body to extend along radial direction of the tube body and wind and extend around the tube outer surface in helical manner, wherein microscale channels are formed on at least one lateral surface of the outer fin.

Abstract: The present invention discloses heat transfer tubes for evaporators in air conditioning and refrigeration systems, comprising: a tube body (1); outer fins (2) extending on an outer wall surface of the tube body (1) and having outer fin walls opposite to the outer fin walls of the adjacent outer fins; channels (6) located between the adjacent fins (2) so as to constitute channel chambers; fin top platforms (3) on respective tops of the outer fins (2), the fin top platforms (3) including fin top edges (3a) extending from both sides of the fin top platforms (3) so that the channel chambers take a form of a cavity structure as a whole; channel chamber openings constituted by gaps between the adjacent fin top edges (3a) of the fin top platforms (3) of the outer fins; and lateral fins (4) arranged on portions or substantially middle portions of the outer fin walls of the outer fins (2) in a height direction of the outer fins (2) and at intervals in an spreading direction of the outer fins (2), so that the cavity st