Abstract: A strapdown inertial navigation heave measurement method using multiple low-pass filter units includes: firstly, collecting data of a gyroscope and an accelerometer by a system, obtaining attitude information of a carrier by using initial alignment, and then, obtaining a relationship matrix between a body coordinate system and a geographic coordinate system by using the attitude information; obtaining a relationship matrix between the geographic coordinate system and a reference coordinate system according to a geographic position, and obtaining a rough vertical acceleration by using a direction cosine matrix, output information of the accelerometer and gravity information; then, filtering out low-frequency signals by using a first filter unit and integration to obtain a relatively accurate velocity signal; and furthermore, enabling the vertical acceleration to be subjected to a second filter unit and integration to obtain an accurate heave displacement.

Abstract: The disclosure discloses a strapdown inertial navigation heave measurement method using multiple low-pass filter units, including: firstly, collecting data of a gyroscope and an accelerometer by a system, obtaining attitude information of a carrier by using initial alignment, and then, obtaining a relationship matrix between a body coordinate system and a geographic coordinate system by using the attitude information; obtaining a relationship matrix between the geographic coordinate system and a semi-fixed coordinate system according to a geographic position, and obtaining a rough vertical acceleration by using a direction cosine matrix, output information of the accelerometer and gravity information; then, filtering out low-frequency signals by using a double-filter unit and one integral link to obtain a relatively accurate velocity signal; and furthermore, enabling the vertical acceleration to be subjected to a triple-filter unit and two integral links to obtain an accurate heave displacement.

Abstract: Embodiments of the present invention relate to a method and system for analyzing user behaviors. The method comprises: generating action sequences according to action identifications in user behavior records; determining a common subsequence based on the action sequences, the common subsequence being a subsequence that is common to at least two action sequences among the action sequences; and constructing a sequence pattern based on the common subsequence.