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: Disclosed is a device for monitoring icing of a transmission line and preventing a tower from falling down, including a power transmission tower, an insulator string and a connecting mechanism; the connecting mechanism includes two connecting plates, and a monitoring-control connector and a damping component are arranged between the two connecting plates; sides of the two connecting plates are respectively provided with connecting grooves matched with two ends of the monitoring-control connector; the monitoring-control connector is provided with a monitoring component in signal connection with a master station; the two ends of the monitoring-control connector are respectively provided with load release components and are fixedly connected with the two connecting plates, and sides of the two connecting plates further from the monitoring-control component are fixedly connected with the power transmission tower and one end of the insulator string respectively, the other end of the insulator string is hung with w

Abstract: The present application discloses a method of quick charging a lithium battery for a brushless direct current motor drive system, including the steps: (1) a constant power charging stage; and (2) a linear charging stage. The above-mentioned method of quick charging a lithium battery for a brushless direct current motor drive system has the advantages of speeding up the charging process and reducing heat generation during the charging process so as to realize short charging time, and shorten the waiting time for battery charging. It has an extensive market prospect for the popularization of the method of quick charging a lithium battery for a brushless DC motor drive system.

Abstract: A method of smoothly starting a Hall-less motor includes the steps of applying voltage to two items of a three-phase motor, determining positioning duty and positioning time so that duty cycle progressively increases from zero to prevent jitter during positioning, using fixed duty cycle so that dragging duty cycle equals to positioning duty cycle, setting initial phase-changing time and phase-changing time when dragging is ended, changing phase after timer is interrupted, generating logic signal by three-phase signal generated by three-phase motor, and transmitting to central processor simultaneously using external interruption method. The method adopts low cost hardware circuit structure, optimizes starting algorithm, and simplifies product design. Algorithm optimization is carried out in every step, and it has the advantages of smooth starting process, short starting time, and almost zero starting failure rate.

Abstract: A constant-power double-speed control system and method based on DC brushless electric tools which may include an inductance device for collecting information about power supply voltage, working current and motor speed during operation of a motor, a two-gear rotational speed switching module for providing different rotational speed options, a constant-power double-speed control module for reading and judging information sent by the two-gear rotational speed switching module and the inductance device, and a motor output power control module for adjusting the motor's output power according to the judged information of the constant-power double-speed control module. This does not only match load and save energy, but also effectively ensures that the output power of supporting battery system is in a normal range so as to protect the battery system.