Abstract: A grass cutting head includes a spool for winding a grass cutting line, a head housing for accommodating the spool, a first guiding structure disposed at least partially in the head housing, and a second guiding structure formed on the spool. The first guiding structure guides the grass cutting line through the head housing when threading the grass cutting line. The second guiding structure guides the grass cutting line to move and be wound around the spool by relative motion created between the spool and the head housing. The head housing includes a first housing and a second housing. The first guiding structure is disposed at least partially in the first housing. The spool is disposed between the first housing and the second housing. The first housing or the second housing is provided with an outer threading hole for allowing the grass cutting line to pass in or out.

Abstract: The present application discloses a cerebral perfusion state classification apparatus and method, a device, and a storage medium. The method includes: acquiring, by a transceiving module, cervical blood flow data from an ultrasound data collecting device; determining, by a processor, cerebral perfusion data corresponding to the cervical blood flow data based on the cervical blood flow data and a mapping relationship between the cervical blood flow data and the cerebral perfusion data, and classifying cerebral perfusion states of a plurality of brain regions based on blood perfusion characteristics of the plurality of brain regions in the cerebral perfusion data.

Abstract: A grass cutting head includes a spool for winding a grass cutting line, a head housing for accommodating the spool, a first guiding structure disposed at least partically in the head housing, and a second guiding structure formed on the spool. The first guiding structure guides the grass cutting line through the head housing when threading the grass cutting line. The second guiding structure guides the grass cutting line to move and be wound around the spool by relative motion created between the spool and the head housing. The head housing includes a first housing and a second housing. The first guiding structure is disposed at least partially in the first housing. The spool is disposed between the first housing and the second housing. The first housing or the second housing is provided with an outer threading hole for allowing the grass cutting line to pass in or out.

Abstract: A grass cutting head includes a spool for winding a grass cutting line, a head housing for accommodating the spool, a first guiding structure disposed at least partially in the head housing, and a second guiding structure formed on the spool. The first guiding structure guides the grass cutting line through the head housing when threading the grass cutting line. The second guiding structure guides the grass cutting line to move and be wound around the spool by relative motion created between the spool and the head housing. The head housing includes a first housing and a second housing. The first guiding structure is disposed at least partially in the first housing. The spool is disposed between the first housing and the second housing. The first housing or the second housing is provided with an outer threading hole for allowing the grass cutting line to pass in or out.

Abstract: A grass cutting head includes a spool for winding a grass cutting line, a head housing for accommodating the spool, a first guiding structure formed on the head housing, and a second guiding structure formed on the spool. The first guiding structure guides the grass cutting line through the head housing when threading the grass cutting line. The second guiding structure guides the grass cutting line to move and be wound around the spool by relative motion created between the spool and the head housing. The head housing includes a first housing and a second housing. The first guiding structure is formed on the second housing. The spool is disposed between the first housing and the second housing. The first housing or the second housing is provided with an outer threading hole for allowing the grass cutting line to pass in or out.