Abstract: The present disclosure discloses a microphone module including at least two MEMS microphones, a printed circuit board, and a shell, each of the MEMS microphones is provided a sound inlet hole, a plurality of first sound pickup holes are provided on the printed circuit board, a plurality of second sound pickup holes are provided on the shell, each of the first sound pickup holes is communicating with the corresponding sound inlet hole and the corresponding second sound pickup hole, a diameter dimension of each of the first sound pickup holes is D1 mm, a distance between a center axes of adjacent sound inlet holes is greater than or equal to 25D1 mm and less than or equal to 43D1 mm. Compared with the related art, the microphone module disclosed by the present disclosure could have a better sound recognition effect.

Abstract: The present disclosure discloses a microphone module including at least two MEMS microphones, a printed circuit board, and a shell, each of the MEMS microphones is provided a sound inlet hole, a plurality of first sound pickup holes are provided on the printed circuit board, a plurality of second sound pickup holes are provided on the shell, each of the first sound pickup holes is communicating with the corresponding sound inlet hole and the corresponding second sound pickup hole, a diameter dimension of each of the first sound pickup holes is D1 mm, a distance between a center axes of adjacent sound inlet holes is greater than or equal to 25D1 mm and less than or equal to 43D1 mm. Compared with the related art, the microphone module disclosed by the present disclosure could have a better sound recognition effect.

Abstract: An electronic device, and a shell module for packaging an electronic device, comprising a first shell and a second shell connected through an engagement-locking structure with a protruding inserting portion arranged on a first side of the first shell. The inserting portion is located between two engagement portions on the first side of the first shell, an inserting space is formed between two engagement portions that are on a third side of the second shell and nearest to the inserting portion, and a non-inserting space is formed between two locking portions that are on a fourth side of the second shell and nearest to the inserting portion. An orthographic projection of the inserting portion onto the inserting space completely falls within the inserting space, and an orthographic projection of the inserting portion onto the non-inserting space is at least partially located outside the non-inserting space, avoiding incorrect assembly.

Abstract: The invention discloses a device for preheating before welding and post-welding heat treatment of tank. The device includes a first roller, two electric heating belts, calipers, a thermostat, two positioners and hinges. Both of the electric heating belts are arranged around the tank and distributed on both sides of the welded seam. A number of calipers are provided on both sides of each electric heating belt, one end of each caliper can operatively clamp the side of the electric heating belt, another end of each caliper is rotatably connected to a first roller. The hinge is connected to the electric heating belt, and one end of the hinge away from the electric heating belt is in a fixed state. The heating temperature of the electric heating belt is controlled, thereby realizing preheating of the tank before welding, heat preservation during welding and post-welding heat treatment without transferring.

Abstract: The invention discloses a device for preheating before welding and post-welding heat treatment of tank. The device includes a first roller, two electric heating belts, calipers, a thermostat, two positioners and hinges. Both of the electric heating belts are arranged around the tank and distributed on both sides of the welded seam. A number of calipers are provided on both sides of each electric heating belt, one end of each caliper can operatively clamp the side of the electric heating belt, another end of each caliper is rotatably connected to a first roller. The hinge is connected to the electric heating belt, and one end of the hinge away from the electric heating belt is in a fixed state. The heating temperature of the electric heating belt is controlled, thereby realizing preheating of the tank before welding, heat preservation during welding and post-welding heat treatment without transferring.

Abstract: A method of substation-control center two-level distributed modeling for power grid is provided. The method comprises: (1) building a substation model for each of substations, each substation model comprising a network model having a topological structure of the substation devices, parameters of the substation devices and measurement information of each substation devices, and a wiring diagram of each substation based on a whole line identification consistency; (2) uploading each substation model for each of the substations to the control center through a state power dispatching data network; and (3) splicing network models for the substations according to the wiring diagrams of the substations to build a whole power grid model of a whole power grid so as to monitor and control the whole power grid.