3 results about "Signature matrix" patented technology

The present application relates to the technical field of charging pile detection, and discloses an alternating current and direct current charging pile detection method, device and system, the method comprising the following steps: S1, applying a preliminary wideband disturbance signal to a charging pile to be detected; S2, generating an optimized composite disturbance signal according to sensitive frequency band characteristics; S3, synchronously applying the optimized composite disturbance signal to the charging pile to be detected; S4, performing Fourier transform on the output response; S5, constructing a dynamic response signature matrix based on a transfer function; S6, after detection, calculating the difference between the dynamic response signature matrix and stored reference data; and S7, when it is determined that the charging pile to be detected is unqualified, performing structured deviation analysis on the difference. The present application identifies the sensitive frequency band of the system through a preliminary wideband disturbance, and then generates an optimized composite disturbance signal, thereby concentrating energy in the sensitive frequency band to accurately excite. The present application improves the detection speed and signal-to-noise ratio, and achieves the technical effect of fast and efficient testing.

The application provides a homomorphic hash-based multi-party cooperative anti-quantum signature method and system, relates to the technical field of digital signature, and comprises a plurality of participants and a verifier, specifically: each participant generates a pair of public and private keys, wherein the public key is composed of a total public key of all participants, a total signature matrix and a total hash matrix; based on the public and private keys, all participants perform multi-party signature on a target message through a homomorphic hash function, and the generated signature is composed of a total hash challenge value of all participants, a total response vector of all participants and a commitment value high-bit difference value of all participants; according to the signature, the verifier recovers the total commitment value high-bit, and then calculates the total hash challenge value, and through comparison of the total hash challenge value, the legality of the signature is verified; the application realizes multi-user cooperative signature, and obtains security against malicious opponents under a quantum computer.

This invention discloses a lidar loop closure detection method based on hierarchical frequency domain feature extraction. The method includes: a robot collecting point cloud data of the current driving environment using an onboard lidar sensor during its movement, acquiring original lidar point clouds, with each lidar frame corresponding to one original lidar point cloud; dividing the original lidar point cloud into multiple layers according to height, and acquiring the frequency domain signature vectors of the layered sub-point clouds; integrating all frequency domain signature vectors of the lidar frames to obtain a frequency domain signature matrix; determining loop closure constraint factors and correcting the robot pose based on the frequency domain signature matrix corresponding to the current lidar frame acquired by the robot and the frequency domain signature matrices corresponding to the lidar frames to be matched in the historical trajectory; and correcting the robot's motion behavior based on the corrected robot pose. This invention has the advantages of high loop closure detection rate, high detection accuracy, strong detection robustness, and strong real-time performance.