Abstract: A spinel-type nickel-manganese-lithium-containing composite oxide, a preparation method thereof, and a secondary battery and an electric apparatus containing the same are provided. A body material of the spinel-type nickel-manganese-lithium-containing composite oxide is represented by a general formula LixNiyMnzMmO4Qq, and both element P and one or more elements selected from elements Nb, W, and Sb are doped in the body material, where based on mass of the spinel-type nickel-manganese-lithium-containing composite oxide, doping content k of the element P satisfies 0.48 wt %?k?3.05 wt %, doping content g of the one or more elements selected from the elements Nb, W, and Sb satisfies 0.05 wt %?g?0.31 wt %, and 2?k/g?20. The secondary battery provided in this application has good high-temperature storage performance and high-temperature cycling performance.

Abstract: A display unit, including a display panel including a static portion and a retractable portion; a tension bar coupled to the retractable portion of the display panel; a midframe coupled to the static portion of the display panel; a sync plate including curved slots extending from a first side to a second side of the sync plate, each of the curved slots including a respective first end and a respective second end, the sync plate moveably coupled to the midframe; counterweight springs each including a first end and a second end, the second ends each including a protrusion, the counterweight springs coupled between the midframe and the sync plate such that the protrusions of the second ends of each of the counterweight springs are movably coupled within a respective curved slot of the sync plate; torsion springs coupled between the tension bar and the second side of the sync plate.

Abstract: A positive electrode material, a preparation method of same, a positive electrode plate, a secondary battery, and an electrical device are described. The positive electrode material includes a ternary positive electrode substrate and optionally a coating layer. The coating layer coats a surface of the ternary positive electrode substrate. The ternary positive electrode substrate includes Li, Ni, Al, and an M element. The M element includes a combination of one or more of Mn, Co, Ti, Zr, W, Nb, Mo, Si, Mg, B, Cr, or Ta. A volume-based particle size distribution curve of the positive electrode material is a bimodal curve.

Abstract: A mobile device may receive a plurality of polling messages with each polling message including an identifier of a particular access device transmitting the polling message. Each polling message of the plurality of polling messages may be transmitted during a polling phase. The mobile device may select a timeslot of a response phase of a communication session. The mobile device may transmit a response message during the timeslot of the response phase. The mobile device may receive, during a third phase, an assignment message including an assigned timeslot for a response phase of a future session. The mobile device may perform secure ranging with one or more access devices of the plurality of access devices during the future session using the assigned timeslot. The mobile device may provide an access credential to the one or more access devices based on a location determined using the secure ranging.

Abstract: A positive electrode material, including a core and a shell layer are provided. In some embodiments, a molecular formula of the core is Li1+aNixCoyMn1-x-yM1zO2, 0.8?x<1.0, 0<y<0.2, 0<a<0.1, 0?z<0.1, and M1 is selected from at least one of Al, Ta, and B; and a molecular formula of the shell layer is Li1+bComAlnNb1-m-nM2cO2, 0.85?m<1.0, 0<n<0.15, 0<b<0.1, 0.001?1-m-n?0.02, 0?c<0.05, and M2 is selected from at least one of W, Mo, Ti, Zr, Y, and Yb.

Abstract: Embodiments of the present disclosure provide a method and an apparatus for training a model, an electronic device, and a medium. This method includes: generating a first group of features and a second group of features respectively from a first sample set and a second sample set based on the model, wherein the first sample set is of a first category, and the second sample set is of a second category different from the first category; generating a first similarity matrix for the first sample set and the second sample set based on the first group of features and the second group of features; determining a first loss for the first sample set and the second sample set based on the first similarity matrix; and updating the model based on the first loss.

Abstract: The present application provides a positive electrode active material and a preparation method thereof, a positive electrode sheet, a secondary battery, and an electric apparatus. The positive electrode active material includes a first positive electrode active material and a second positive electrode active material. The first positive electrode active material is a nickel-iron-manganese-copper quaternary sodium battery positive electrode active material; and a chemical formula of the second positive electrode active material is Naa2[Nib2Fec2Mnd2Me2]O2, where 0.8?a2<1, 0.01?b2<0.35, 0.01?c2<0.35, 0.01?d2<0.35, 0?e2<0.1, b2+c2+d2+e2=1, and the M element includes any one or more of Zn, Ti, Zr, Mg, La, Y, Co, Cr, Al, K, V, Mo, W, Sr, Ta, Nb, or Ca.

Abstract: This application relates to a ternary precursor for making a material for positive electrodes in lithium batteries. In the ternary precursor, primary particles or whiskers of the ternary precursor are distributed in a radial direction. A deformation stacking fault probability fD of the ternary precursor is ?2.5%. This application further relates to a preparation method of the ternary precursor, a ternary positive electrode material, a secondary battery, a battery module, a battery pack, and an electric apparatus.

Abstract: A deeply coupled system for energy utilization, cooling and carbon dioxide energy storage in a data center includes the data center, including: a power supply subsystem and a cooling and heat dissipation subsystem; and a carbon dioxide energy storage subsystem. The carbon dioxide energy storage subsystem is combined with a new energy power generation subsystem and/or a utility grid as a power supply source, coupled to the power supply subsystem, and configured to supply power to the data center. A working fluid circulation loop of the carbon dioxide energy storage subsystem is coupled to the cooling and heat dissipation subsystem, and a carbon dioxide working fluid extracted from the working fluid circulation loop serves as a cooling medium to cool and dissipate heat from the data center. The deeply coupled system can provide stable and uninterrupted power to the data center and realize optimized allocation of energy usage.

Abstract: The present disclosure discloses a control method of a measurement system. The system includes a navigation module, a laser distance measuring module and a support portion. The method includes: obtaining relative position parameters between the navigation module and the laser distance measuring module; obtaining parameter information of the support portion; switching to a first measurement mode, wherein coordinates of a point to be measured are obtained according to first measurement information and the parameter information; switching to a second measurement mode, wherein coordinates of a point to be measured are obtained according to the second measurement information and the parameter information; and switching to a third measurement mode, wherein coordinates of the point to be measured are obtained according to the second measurement information, the relative position parameters, and the distance information.

Abstract: A positive electrode active material and a preparation method therefor, a positive electrode plate, a battery cell, a battery, and an electric apparatus are provided, pertaining to the field of battery technology. The positive electrode active material includes: a positive electrode base material, and a first coating layer and a second coating layer sequentially coating a surface of primary particles of the positive electrode base material; where a concentration of lithium element in the first coating layer is lower than a concentration of lithium element in the positive electrode base material, and the second coating layer includes an ion conductor material. The technical solution of this application can improve cycling performance of a battery cell.

Abstract: An air conditioner includes a controlled device, a frequency converter, and a controller. The controller is configured to: determine a present operating frequency of the controlled device, and a present output current and a present input power of the frequency converter; determine a present efficiency of the frequency converter according to the present operating frequency of the controlled device and the present output current of the frequency converter; and determine a present input power of the frequency converter according to the present efficiency of the frequency converter and the present output power of the frequency converter.

Abstract: A positive electrode active material, a preparation method thereof, a positive electrode plate, a secondary battery, and an electric apparatus. The positive electrode active material includes: a core and a first coating layer applied on at least a portion of an outer surface of the core, the core includes a lithium-containing nickel-based transition metal oxide, and the first coating layer includes cerium element. In the lithium-containing nickel-based transition metal oxide, a molar proportion of nickel element among all elements excluding lithium element and oxygen element ranges from 50% to 100%.

Abstract: A cascade display rack and package method and installation method thereof, comprising: a first assembly, comprising a plurality of cascade plates forming a cascade, and a plurality of light band plates detachably connected on the plurality of cascade plates; a second assembly, comprising a back panel, and a first side panel and a second side panel rotatably provided at both ends of the back panel; a plurality of erecting panels are provided at both ends of the plurality of cascade plates in the first assembly, the first side panel and the second side panel are fixable on the plurality of erecting panels to connect the first assembly and the second assembly.

Abstract: A control method and a control device for a head-mounted display apparatus, an electronic apparatus and a computer-readable storage medium are disclosed, which relate to a technical field of head-mounted display apparatuses. The method comprises: obtaining distance information between the head-mounted display apparatus and a target apparatus, wherein the head-mounted display apparatus is wirelessly connected to the target apparatus; detecting an interaction behavior between the head-mounted display apparatus and the target apparatus according to the distance information; adjusting a color of a light-shielding sheet of the head-mounted display apparatus according to the interaction behavior.

Abstract: A lower vehicle body rear structure includes a rear floor integrally formed in a die-casting mode, rear floor longitudinal beam rear sections fixedly connected to the rear floor, a shelf, and a spare tire cabin. Rear floor longitudinal beams arranged on the two sides of the rear floor, and a rear floor middle cross beam and a rear floor rear cross beam which are connected between the rear floor longitudinal beams are formed on the rear floor, and rear wheel covers connected to the rear floor longitudinal beams are respectively arranged on the two sides of the rear floor. The shelf is located above the rear floor, and the two ends of the shelf are connected to the rear wheel covers by means of connecting plates; and the rear floor, the shelf and the two connecting plates are connected to form an annular structure.

Abstract: This application relates to a positive active material, a method for preparing same, an electrode plate, a secondary battery, and an electrical device. The positive active material includes: a core material, including a lithium-rich manganese-based positive electrode material; and a cladding layer, covering an outer surface of the core material, where the cladding layer includes an oxygen-ion conductor and a lithium-ion conductor.

Abstract: Disclosed are a method and apparatus for calibrating the sound quality of an earphone, and a device and a storage medium. The method includes: acquiring frequency response data of an earphone to be calibrated and a preset target frequency response curve; according to the target frequency response curve, determining whether the frequency response data meets the calibration condition; if it is determined that the frequency response data meets the calibration condition, performing section dividing on the frequency response data, to obtain a filter parameter by means of searching based on a preset genetic algorithm, and calibrating the frequency response data according to the filter parameter, to obtain new frequency response data; and when it is determined that the new frequency response data does not meet the calibration condition, determining to calibrate the sound quality of the earphone to be calibrated based on the filter parameter.

Abstract: A dimming method of a display device and a display device are provided. The dimming method includes: obtaining a target brightness of the display device; when the target brightness is less than a first preset dimming brightness threshold, setting a dimming mode of the display device to a PWM dimming mode; and, when the target brightness is larger than a second preset dimming brightness threshold, setting the dimming mode of the display device to a DC dimming mode. The first preset dimming brightness threshold is less than the second preset dimming brightness threshold. When the target brightness is less than or equal to the second preset dimming brightness threshold and the target brightness is larger than or equal to the first preset dimming brightness threshold, the dimming mode of the display device is set to a transition dimming mode.