Abstract: Provided are an interaction method and apparatus in a live streaming room, and a device and a storage medium. The method comprises: in response to a trigger operation for a preset duet entry on a live streaming room page, jumping from the live streaming room page to a camera capture page, wherein a host portrait cutout corresponding to the live streaming room page is displayed on the camera capture page and a capture control is provided on the camera capture page acquiring multimedia information captured by a camera, in response to a trigger operation for the capture control on the camera capture page, wherein the multimedia information comprises an image or a video; and synthesizing the multimedia information with the host portrait cutout to obtain a duet multimedia product.

Abstract: In the present disclosure, the multi-level AC/DC conversion circuit and the multi-level DC/DC conversion circuit calculate the duty ratio of synchronous rectification switch according to the input voltage, the output voltage, the interval time of turning on the main switch, the switching cycle and the duty ratio of main switch, thereby eliminating the need for additional zero-current detecting function or zero-crossing detection circuit in conventional AC/DC conversion circuits. Accordingly, for the multi-level AC/DC conversion circuit and the multi-level DC/DC conversion circuit of the present disclosure, the cost is reduced, and the reliability is enhanced.

Abstract: A multi-level conversion circuit and a control method for flying capacitor voltage thereof are provided. In the multi-level conversion circuit, each flying capacitor is connected between a common connection node of the lower switches connected therewith and a common connection node of the upper switches connected therewith. The control method includes steps of: (a) determining the main switch and synchronous rectification switch of the lower and upper switches; (b) acquiring an adjustment value corresponding to each flying capacitor; (c) adjusting a duty ratio of the main switch according to the adjustment value corresponding to the flying capacitor connected therewith; and (d) when the multi-level conversion circuit working in a CCM, increasing a phase-shift angle between the main switches by an angle to make a peak value or a valley value of an inductor current remain unchanged before and after adjusting the duty ratio.

Abstract: A multi-level conversion circuit and a control method for flying capacitor voltage thereof are provided. In the multi-level conversion circuit, each flying capacitor is connected between a common connection node of the lower switches connected therewith and a common connection node of the upper switches connected therewith. When the conversion circuit works in a DCM, the control method includes steps of: (a) determining the main switch and synchronous rectification switch of the lower and upper switches; (b) acquiring an adjustment value corresponding to each flying capacitor; and (c) adjusting a duty ratio of the main switch according to the adjustment value corresponding to the flying capacitor connected therewith, wherein the adjustment trend of the duty ratio under D<(N?2)/(N?1) is opposite to that under (N?2)/(N?1)<D?1, and D is the duty ratio before the adjustment.

Abstract: Provided are an interaction method and apparatus in a live streaming room, a device, and a storage medium. The method comprises: in response to a trigger operation for a preset drawing entry on a live streaming room page, jumping to a graphic drawing page from the live streaming room page, a drawing trajectory set for a preset object being displayed on the graphical drawing page; when a drawing stroke on the graphic drawing page is received, matching the drawing stroke with the drawing trajectory; and if it is determined that the drawing stroke is successfully matched with the drawing trajectory, displaying prompt information about successful participation in a preset activity, the preset activity and the preset drawing entry having a correspondence.

Abstract: A non-road mobile machinery (NRMM) is provided and includes a fuel storage device, a fuel supply device, a vapor adsorption device, and an engine body. The vapor adsorption device is provided with an air vent communicated to the atmosphere. A vapor discharge hole of the fuel storage device is communicated to an adsorption vent of the vapor adsorption device. The NRMM also includes a valve mechanism connected between a desorption vent of the vapor adsorption device and an intake channel of the engine body. The valve mechanism is conducted with the working of the engine body and blocked with the stop of the engine body. The NRMN improves the evaporation emission performance of the NRMM when compared to the prior art and solves the problem that the evaporation emissions of the NRMM in the prior art are prone to exceed the standard.

Abstract: A multilevel conversion circuit having a flying capacitor is provided, including: a first bridge arm; a second bridge arm including a flying capacitor, the midpoints of the second and first bridge arms connected to a series branch defined by a first current limiting circuit, a power supply and an inductor; a DC bus capacitor connected in parallel to the first and second bridge arms; a rectifier circuit having an input end coupled to the power supply and an output end connected to a first auxiliary power supply; and a controller coupled to the first auxiliary power supply and the plurality of switches of the second bridge arm to control corresponding switches of the second bridge arm, the power supply charges the flying capacitor through the corresponding switches of the first and second bridge arms and the first current limiting circuit.

Abstract: A multilevel conversion circuit having a flying capacitor is provided, including: a first bridge arm; a second bridge arm including a flying capacitor, the midpoints of the second and first bridge arms connected to a series branch defined by a first current limiting circuit, a power supply and an inductor; a DC bus capacitor connected in parallel to the first and second bridge arms; a rectifier circuit having an input end coupled to the power supply and an output end connected to a first auxiliary power supply; and a controller coupled to the first auxiliary power supply and the plurality of switches of the second bridge arm to control corresponding switches of the second bridge arm, the power supply charges the flying capacitor through the corresponding switches of the first and second bridge arms and the first current limiting circuit.

Abstract: Multilevel conversion circuit having a flying capacitor and method for precharging the same are provided. The multilevel conversion circuit includes: a first bridge arm including a plurality of switches connected in series; a second bridge arm including a plurality of switches connected in series and a flying capacitor group, midpoints of the two bridge arms connected to a power supply and an inductor to form a series branch; a DC bus capacitor to which the two bridge arms are connected in parallel; a first voltage clamping module connected between a first end of the flying capacitor group and a first end of the DC bus capacitor; and a second voltage clamping module connected between a second end of the flying capacitor group and a second end of the DC bus capacitor.

Abstract: The application provides a power supply device comprising two input ports disposed at a front end of the power supply device; at least one fan disposed behind the two input ports and two isolated power supplies connected respectively to the corresponding one of the two input ports and disposed behind the two input ports and the at least one fan. Each of the isolated power supplies comprises a main power circuit having at least one module, and each module comprises a PCB and a magnetic element and/or switching devices. The at least one module includes an isolated circuit module comprises a transformer having windings formed by laying copper in the PCB and the magnetic core fixed on the PCB. And at least one fan is configured for heat dissipation of the at least one module.

Abstract: An engine balancing system includes an engine body. At least two slider-crank mechanisms are provided inside the engine body. One of the slider-crank mechanisms is arranged opposite to the other slider-crank mechanism. A slider in one of the slider-crank mechanisms is moved at a speed and acceleration similar to a speed and acceleration of a slider in the other slider-crank mechanism. The slider-crank mechanism includes a connecting rod and a crankshaft with a crank. One end of one of the slider-crank mechanisms and one end of the other slider-crank mechanism are connected to the same crankshaft through the crank. The balancing system can effectively eliminate first-order, second-order and higher-order vibrations generated during engine operation, thus reducing the probability of equipment damage.

Abstract: The invention provides primary batteries that incorporate a desodiated sodium transition metal oxide into the positive electrode (a cathode). Batteries of the invention using a desodiated sodium transition metal oxide in the cathode exhibit discharge voltages, battery capacities, and energy densities higher than a traditional Zn—MnO2 dry cell battery, such as a commercially available AA battery. These batteries are also advantageous over comparable lithium ion batteries due to the high abundance and low cost of sodium precursor materials with similar electrical performance.

Abstract: An engine balancing system includes an engine body. At least two slider-crank mechanisms are provided inside the engine body. One of the slider-crank mechanisms is arranged opposite to the other slider-crank mechanism. A slider in one of the slider-crank mechanisms is moved at a speed and acceleration similar to a speed and acceleration of a slider in the other slider-crank mechanism. The slider-crank mechanism includes a connecting rod and a crankshaft with a crank. One end of one of the slider-crank mechanisms and one end of the other slider-crank mechanism are connected to the same crankshaft through the crank. The balancing system can effectively eliminate first-order, second-order and higher-order vibrations generated during engine operation, thus reducing the probability of equipment damage.

Abstract: A system for controlling operation of a brushless DC motor is provided. The system includes a memory, driving profile and motor controllers, and an inverter. The memory stores: a scaling factor indicative of how much to increase an operating parameter of a base driving profile; and the base driving profile indicative of speed over time of a drive cycle of the brushless DC motor. The driving profile controller generates a motor driving profile, indicating an operating parameter for driving the brushless DC motor, where the operating parameter is based on (i) the scaling factor, and (ii) the base driving profile. The controller generates a control signal based on the operating parameter of the motor driving profile. The inverter: receives a direct current from a DC source; responsively to the control signal, converts the direct current to an alternating current; and drives the brushless DC motor via the alternating current.

Abstract: An apparatus includes a clamp control circuit configured to control a first current to have a magnitude substantially equal to that of a second current when the second current has a first flow direction. The clamp control circuit is configured to control the first current to be substantially zero when the second current has a second flow direction. A method includes determining a value of a first current, controlling a second current to have a substantially zero value when the first current flows in a first direction, and controlling the second current to have a magnitude substantially equal to that of the first current when the first current flows in a second direction. The first current flows in the first direction when a winding of a motor is being supplied with energy and flows in the second direction when the winding of the motor is discharging energy.