Abstract: A navigation method, device, and system are provided in this application. The method includes: obtaining a first target location and a second target location (101), where the first target location is a location closest to a start location on K road segments, the second target location is a location closest to an end location on the K road segments, and K is a positive integer; obtaining a first path from the first target location to the second target location based on a vector pathfinding algorithm and the K road segments (102); obtaining a second path from the start location to the first target location and a third path from the second target location to the end location (103); and determining a fourth path from the start location to the end location (104).

Abstract: This application relates to methods and apparatuses for presenting object annotation information. An example method includes: obtaining a target object in a specified scene, where the specified scene is a scene presented at a target location; and presenting annotation information of the target object on an annotation facade that is of the target object and that is presented on a display interface, where the annotation facade is determined from at least two visible facades of the target object based on projection regions that are for the at least two visible facades and that are presented on the display interface, and the visible facade is a facade visible to the target location in exterior facades of the target object.

Abstract: Provided are a transmission line module for a rotary traveling wave oscillator (RTWO) and a design method thereof. The transmission line module includes a substrate. The upper surface of the substrate is provided with a grounding metal layer, that is, a metal ground. The metal ground is provided with a rectangular groove. The rectangular groove penetrates front and rear sides of the metal ground along a length direction of the rectangular groove. The thickness of the rectangular groove is the same as the thickness of the metal ground. The rectangular groove is filled with a silicon dielectric plate that has the same shape and size as the rectangular groove. The upper surface of the silicon dielectric plate is provided with two parallel transmission lines along the length direction of the rectangular groove.

Abstract: This application provides a visual feature database construction method, including: obtaining a database creation image; performing feature extraction on the database creation image to obtain a feature point of the database creation image and a descriptor of the feature point of the database creation image; intersecting a ray corresponding to the feature point of the database creation image with a 3D model, to determine the 3D position of the intersection point at which the ray intersects with the 3D model as the 3D position of the feature point of the database creation image; and writing the descriptor of the feature point of the database creation image and the database creation image into a visual feature database, to construct the visual feature database.