Chinese Academy of Sciences

Beijing Geekplus Technology Co. Ltd.

East China Normal University

Douyin Vision Co., Ltd.

Haoyu Wang

Kai Liu

Kai Sun

Chao Xu

Xiaolin Huang

Lei Xue

Mengyang Zhai

Fengchang Bu

Xun Wu

Yuxing Han

Chengcheng Yang

Embodiments of the present disclosure provide a method and apparatus for estimating a number of distinct values in a database system, a device, and a medium. The method includes: reading and loading, from a distributed file system, a model for NDV estimation into a kernel of the database system; generating feature data of sample data of a target column in the database system; determining, using the model that has been loaded into the kernel, an estimated NDV for the target column based on the feature data; and storing the estimated NDV of the target column for use by the kernel of the database system.

Method, apparatus, electronic device, and medium for processing database query

A management method applied to the goods-to-person system includes: in response to a task of putting products on shelves, calculating popularity of a product to be put on shelf according to historical sales order data of the product to be put on shelf, and matching the popularity of the product to be put on shelf with popularity of a shelf to determine a shelf area; selecting a goods location with space randomly in the determined shelf area, Wherein the goods location is used for storing the product to be put on shelf; and controlling a mobile robot to transport a shelf where the goods location is located to a work station.

Management method, device and system applied to goods-to-person system, server and computer storage medium

The present disclosure relates to a discrete element method (DEM)-based simulation method and system for acoustic emission (AE). The simulation method includes: arranging a monitoring point on a surface of a numerical model; monitoring a velocity waveform of the monitoring point; and analyzing the velocity waveform to obtain a hit, energy, and a b-value of AE. The method in the present disclosure can resolve problems of principle incompliance, poor authenticity, and high occupation of calculation resources in a traditional simulation method for AE.

Discrete element method-based simulation method and system for acoustic emission

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Beijing, China

Haoyu Wang