Abstract: Disclosed is a method for designing a reentry trajectory based on flight path angle planning, including the following steps: S1. extracting an actual operating parameter of an aircraft, setting a maximum dynamic pressure qmax a maximum stagnation point heat flux {dot over (Q)}max, and a maximum overload nmax according to a mission requirement, and solving for a velocity-height boundary of a reentry trajectory; S2. solving for a reentry trajectory in an initial descent stage according to differential equations of reentry motion, and setting up a flight-path-angle lower limit ?min(V) according to the reentry trajectory in the initial descent stage, the velocity-height boundary, and a target point in a velocity-height phase plane; and S3. planning, based on the flight-path-angle lower limit ?min(V), a flight path angle satisfying terminal constraints, and calculating a corresponding bank angle to obtain a reentry trajectory.

Abstract: A method for directly planning a reentry trajectory in a height-velocity profile includes the following steps: S1, extracting an actual working parameter of an aircraft, setting the maximum value {dot over (Q)}max of a stagnation point heat flux, the maximum value qmax of dynamic pressure, and the maximum value nmax of overload according to the mission requirement, and solving the height-velocity boundary of the reentry trajectory, that is, a lower boundary of the reentry trajectory in the height-velocity profile; S2, solving a reentry trajectory of an initial descent stage according to differential equations of reentry motion, and determining a starting point of a trajectory of a gliding stage according to the trajectory of the initial descent stage; and S3, planning a trajectory in the height-velocity profile satisfying terminal constraints based on the lower boundary in the height-velocity profile, and calculating a corresponding bank angle, to obtain the reentry trajectory.

Abstract: A method for directly planning a reentry trajectory in a height-velocity profile includes the following steps: S1, extracting an actual working parameter of an aircraft, setting the maximum value {dot over (Q)}max of a stagnation point heat flux, the maximum value qmax of dynamic pressure, and the maximum value nmax of overload according to the mission requirement, and solving the height-velocity boundary of the reentry trajectory, that is, a lower boundary of the reentry trajectory in the height-velocity profile; S2, solving a reentry trajectory of an initial descent stage according to differential equations of reentry motion, and determining a starting point of a trajectory of a gliding stage according to the trajectory of the initial descent stage; and S3, planning a trajectory in the height-velocity profile satisfying terminal constraints based on the lower boundary in the height-velocity profile, and calculating a corresponding bank angle, to obtain the reentry trajectory.

Abstract: Disclosed is a method for designing a reentry trajectory based on flight path angle planning, including the following steps: S1. extracting an actual operating parameter of an aircraft, setting a maximum dynamic pressure nmax a maximum stagnation point heat flux {dot over (Q)}max, and a maximum overload nmax according to a mission requirement, and solving for a velocity-height boundary of a reentry trajectory; S2. solving for a reentry trajectory in an initial descent stage according to differential equations of reentry motion, and setting up a flight-path-angle lower limit ?min(V) according to the reentry trajectory in the initial descent stage, the velocity-height boundary, and a target point in a velocity-height phase plane; and S3. planning, based on the flight-path-angle lower limit ?min(V), a flight path angle satisfying terminal constraints, and calculating a corresponding bank angle to obtain a reentry trajectory.

Abstract: Removing an embedded barcode in an image. A barcode-embedding area in an image is acquired. Pixels in the barcode-embedding area can be changed from a RGB color space to a color space with a luminance component. The luminance values of the pixels can be determined on a dark side or a light side. The luminance values of the pixels on the dark side or the light side can be mapped to luminance values falling into a whole range of a luminance interval. The pixels in the barcode-embedding area can be changed from the color space with the luminance component to the RGB color space.

Abstract: A method, system, and computer product for driving a display system in a screen protection mode includes receiving one or more image data, generating a first image signal and a second image signal based on the one or more image data, responsive to receiving an input indicating a screen protection mode, displaying a first image on a display screen of the display system based on the first image signal, displaying a second image on the display screen based on the second image signal, and passing through the first image by a viewing device and blocking the second image by the viewing device, so that a viewer wearing the viewing device indentifies the first image. Left-eye and right-eye lenses of the viewing device are configured to operate in a same manner.

Abstract: Removing an embedded barcode in an image. A barcode-embedding area in an image is acquired. Pixels in the barcode-embedding area can be changed from a RGB color space to a color space with a luminance component. The luminance values of the pixels can be determined on a dark side or a light side. The luminance values of the pixels on the dark side or the light side can be mapped to luminance values falling into a whole range of a luminance interval. The pixels in the barcode-embedding area can be changed from the color space with the luminance component to the RGB color space.