Abstract: A method, system and device for active balance control of a battery pack are disclosed. The method includes: calculating a reference balance current ratio of a battery cell to a battery pack in each batch; calculating an actual balance current ratio of the battery cell to the battery pack at each moment in any batch; allowing the actual balance current ratio to track the reference balance current ratio of the corresponding batch in real time by executing a preset tracking algorithm; and performing balance control on the battery pack according to a tracking result. The system includes a first calculation module, a second calculation module, a tracking module, and a balance control module. The device includes a memory and a processor.

Abstract: A method for estimating a state of charge of a battery includes obtaining a discharge voltage and discharge capacity curve of a battery under a preset discharge current, in responding to an order for estimating the state of charge of the battery; matching the discharge voltage and discharge capacity curve with a plurality of standard curves in a database, thereby obtaining an optimal matching curve with respect to the discharge voltage and discharge capacity curve; and calculating the state of charge of the battery according to the optimal matching curve, under a preset discharge stage. The present method can accurately calculate the state of charge of the battery with simple calculation manners.

Abstract: The present invention discloses a method for real-time positioning of a smart device, comprising: getting tri-axial acceleration sequences truncated in turn by using a preset time period in the world coordinate individually; acquiring a dominate frequency fstep by applying fast Fourier transform (FFT) on the truncated Z-axis acceleration sequence, using a band-pass filter with a pass band [fstep?0.5 Hz, fstep+0.5 Hz] to filter the truncated tri axial acceleration sequences individually; comparing the time domain waveform form from the filtered Z-axis acceleration sequence with a preset step threshold, and counting each peak above the threshold as a step to acquire a user's step number in the present time period; determining the moving direction of the smart device in the time period by calculating the filtered X-axis and Y-axis acceleration sequences; determining the current position of the smart device by calculating the user's step number and the moving direction of the smart device.

Abstract: A method for indoor localization using nomadic access points, comprising the following steps: a target object transmits a modulated signal over wireless channels to nearby access points, wherein the access points include both static access points and nomadic access points; the access points measure channel state information via the signal from the target object, after that, the static access points export the channel state information to a server, the nomadic wireless access point report the channel state information along with their coordinates of the current sites to the server; and based on the channel state information, the server determines the target object's relative proximity to two arbitrary access points, then based on the result of the relative proximity determination and the coordinates, the server estimates a feasible region for the target object with a space partition-based algorithm.

Abstract: A nanoporous ceramic membrane and preparation method thereof is provided. The nanoporous ceramic membrane is prepared by halloysite nanotubes (HNTs), and its porosity is between 35% to 85%. This method comprises steps as following: HNTs and polymers with a certain ratio are dispersed in organic solvent, and HNTs/polymer composite fibers are prepared through electrospinning method; after the HNTs/polymers composite fibers are laminated, they are sintered at high temperature in a certain or vacuum atmosphere, and a nanoporous ceramic membrane is obtained. Ceramic membrane prepared by this method is corrosion resistant, thermal resistant, and have large specific surface area, it may widely applied in the field of filtration, catalyst carrier and purification of high-temperature gas, etc.

Abstract: A nanoporous ceramic membrane and preparation method thereof is provided. The nanoporous ceramic membrane is prepared by halloysite nanotubes (HNTs), and its porosity is between 35% to 85%. This method comprises steps as following: HNTs and polymers with a certain ratio are dispersed in organic solvent, and HNTs/polymer composite fibers are prepared through electrospinning method; after the HNTs/polymers composite fibers are laminated, they are sintered at high temperature in a certain or vacuum atmosphere, and a nanoporous ceramic membrane is obtained. Ceramic membrane prepared by this method is corrosion resistant, thermal resistant, and have large specific surface area, it may widely applied in the field of filtration, catalyst carrier and purification of high-temperature gas, etc.