5results about How to "Guaranteed imaging accuracy" patented technology

This invention discloses a dual-spectrum hierarchical architecture and CT detector based on X-rays, relating to the field of medical CT equipment technology. It includes: a scintillator layer capable of receiving high-energy X-rays and low-energy X-rays respectively; and several sets of metal sheets positioned on one end face of the scintillator layer, wherein the metal sheets can block high-energy or low-energy X-rays irradiating a portion of the scintillator layer. This invention solves the technical problems of complex structure, low yield, and high cost of existing dual-spectrum CT detectors.

The application discloses a kind of based on two-dimensional weighted back projection and linear base function interpolation trunk three-dimensional imaging method, comprising: selecting several different measurement heights of to-be-imaged trees, using stress wave measuring equipment respectively at different heights to carry out stress wave data acquisition;Using two-dimensional weighted back projection algorithm reconstructs the stress wave velocity field of each layer, obtains the control point set needed for linear base function interpolation;All known control point set is mapped to three-dimensional coordinate system, and with the wave speed v corresponding to each point constitutes three-dimensional feature point cloud;Linear base function interpolation of using linear kernel is used to carry out interpolation reconstruction, and function F ( x , y , z ) are fitted;According to fitting function F ( x , y , z ) all point sets located in three-dimensional fault imaging region are calculated;Using the display method of point cloud, the points inside imaging region are visualized and displayed.The application significantly improves three-dimensional imaging speed and defect recognition accuracy in actual scene, and is suitable for nondestructive testing and evaluation of three-dimensional defects inside trunk.

The application discloses a high-resolution acoustic imaging method based on adaptive subspace weighting, which comprises the following steps: reading a multi-channel time-domain acoustic signal collected by a microphone array; generating a dynamic adaptive window function based on the spectral characteristics of a current signal frame to suppress spectral leakage; performing windowing processing on the signal by using the dynamic adaptive window function and performing Fourier transform to generate frequency-domain snapshot data; constructing a covariance matrix for each analysis frequency bin and then averaging to obtain a final covariance matrix of a sound source signal; performing diagonal loading processing on the covariance matrix by using an adaptive two-domain regularization method; performing eigenvalue decomposition on the covariance matrix and dividing the covariance matrix into a signal subspace and a noise subspace; establishing a fine scanning grid; precalculating the steering vectors of all grid points and storing the steering vectors as an array manifold matrix; and performing weighted fusion on a fine spatial response map and a coarse spatial response map by using a multi-scale spatial response fusion strategy to generate a final acoustic imaging map.

The invention provides an underground cable three-dimensional imaging method based on terahertz data and X-ray data, and the method comprises the steps: solving dielectric constant distribution and material density distribution according to the terahertz data and the X-ray data, building the incidence relation between the dielectric constant distribution and the material density distribution, and determining projection reconstruction initial parameters; a fitness function is constructed according to the projection data and the projection reconstruction initial parameters, dielectric constant distribution and material density distribution are reconstructed through a quantum genetic optimization algorithm based on the fitness function and the incidence relation, and an initial reconstruction result is obtained; performing cross iterative optimization on the dielectric constant distribution and the material density distribution by using a regularization item constructed by an initial reconstruction result until convergence; and based on the converged dielectric constant distribution and material density distribution, after an X-ray reconstruction image and a terahertz reconstruction image are generated, data fusion and feature optimization are carried out, and a three-dimensional image of the underground cable is obtained. Therefore, a high-precision three-dimensional image of the underground cable is generated by fusing the optimized bimodal image data.

The utility model relates to a zoom lens, relates to the technical field of optical instruments, and aims to solve the technical problems of repeated friction between the outer wall of a zoom lens cone and the inner wall of a linear sleeve, complex structure and difficulty in maintenance in the prior art. The zoom lens comprises a driving unit, a lens group unit, a position adjusting unit and a sliding assembly, the driving unit is connected with the position adjusting unit, and the position adjusting unit and the sliding assembly are connected with the lens group unit. The driving unit drives the lens group unit to move along the sliding assembly through the position adjusting unit; the lens group unit comprises a zoom lens cone group, a compensation lens cone group and a lens cone support. The zoom lens cone group and the compensation lens cone group are connected with the lens cone support. The device can reduce friction, and is simple in structure, easy and convenient to operate and easy to use and maintain.