Abstract: This application provides an electronic device, an audio power amplifier chip, and a device retrieval method, to reduce power consumption of a lost electronic device during a retrieval process. The electronic device includes an audio power amplifier chip, a short-range communication module, and a speaker. The short-range communication module may receive a first instruction from a second electronic device when the electronic device is in an off state. The audio power amplifier chip may output audio through the speaker in response to the first instruction.

Abstract: The present disclosure relates to a diamond electrostatic sand-planting process, including the following steps: modifying a surface of diamond micropowder to polarize an electric field of the diamond micropowder; screening the diamond micropowder to remove the diamond micropowder with a poor polarization effect; coating a surface of a substrate with a primer to increase a binding force with a base glue and the diamond micropowder; continuing to coat a portion of the substrate coated with the primer with the base glue; sand-planting the diamond micropowder into the substrate in an electrostatic field; continuing to coat one surface of the substrate on which sand-planting is completed with a compound glue; and drying and curing one surface of the substrate coated with the compound glue.

Abstract: A composite abrasive paper has at least three surfaces which polished and ground to improve the utilization rate of the abrasive paper and reduce the cost of grinding and polishing abrasive tools. The abrasive paper comprises a first abrasive comprising a first substrate, a first stereo particle layer provided on a surface of the first substrate, a flexible microsphere layer provided on a back surface of the first substrate; a second abrasive comprising a second substrate, a second stereo particle layer provided on surface of the second substrate, a third stereo particle layer provided on a back surface of the first substrate; the first and second abrasive are connected at an edge to form a connection part, the middle non-connection part of the first substrate and the second substrate forms a sealed cavity, the third stereo particle layer is provided opposite to the flexible microsphere layer in the sealed cavity.

Abstract: Embodiments of this application provide a display terminal, and relate to the field of display technologies, to solve the problem that the overall screen-to-body ratio decreases due to a receiver disposed on a display terminal. The display terminal includes a middle frame, a display module, a vibrator, and at least one vibrating plate. The display module is connected to the middle frame, and an accommodation space is formed between the display module and the middle frame. At least a part of the vibrator is disposed in the accommodation space. The vibrator is connected to the display module or the middle frame. The vibrating plate is located in the accommodation space. An upper surface of the vibrating plate is connected to a lower surface of the display module. A lower surface of the vibrating plate faces the middle frame.

Abstract: A terminal protective case and an audio playback system, the case including a housing, a diaphragm, a piezoelectric sheet, and a drive circuit. The housing has a main body part and a fastening frame part, a side of the fastening frame part is fastened to a periphery of the main body part, the fastening frame part and the main body part jointly enclose an accommodating groove configured to accommodate a terminal. The diaphragm is within the main body part, the piezoelectric sheet is fastened to the diaphragm, a front cavity is on a side of the diaphragm, a sound outlet hole is disposed on the main body part, and the sound outlet hole connects the front cavity to the outside of the main body part. The drive circuit is within the main body part and connected to the piezoelectric sheet, and is configured to drive the piezoelectric sheet.

Abstract: The present invention relates to a user device: a processor (20) configured to process an audio signal to derive a first driving signal and a second driving signal, such that the first driving signal comprises only components of the audio signal having frequencies higher than a threshold frequency and such that the second driving signal comprises components of the audio signal having frequencies above and below the threshold frequency; wherein the processor is configured to simultaneously provide the first driving signal and the second driving signal; a first speaker (30), being configured to generate sound based on the first driving signal; and a second speaker (40), being configured to generate sound based on the second driving signal. Furthermore, the present invention also relates to a corresponding method, a computer program, and a computer program product.