5results about How to "Reduce boundary effects" patented technology

This utility model relates to the field of civil engineering technology, specifically a pile foundation shaking table test device. It includes a shaking table body, a container on top of which holds soil and a pile foundation model. The container includes a coaxially arranged rigid inner frame and a rigid outer frame. A flexible sidewall structure is provided between the rigid inner frame and the rigid outer frame. The flexible sidewall structure consists of circumferentially spliced ​​flexible plates and multiple sets of micro-springs connecting the inner surface of the flexible plates to the outer surface of the rigid inner frame. The top and bottom of the flexible plates are connected to the rigid inner and outer frames via sliding guide components to allow radial displacement of the flexible plates in the horizontal plane. This pile foundation shaking table test device, by improving the boundary structure, effectively reduces the soil boundary effect, more realistically simulates the interaction between the pile and soil system under seismic loading, and improves the accuracy of the test.

This invention discloses a baseline removal method for multi-channel magnetocardiogram (MCC) signals based on wavelet low-frequency reconstruction and morphological secondary smoothing. The invention includes: acquiring multi-channel MCC signal data; performing power frequency notch filtering on each channel to suppress the power frequency fundamental frequency and at least one harmonic component; performing configurable IIR low-pass filtering on the notched signal; setting a discrete wavelet transform extension mode and performing discrete wavelet decomposition on the filtered signal; selectively retaining decomposition coefficients based on the retention layer set and setting the remaining coefficients to zero, then performing inverse wavelet reconstruction to obtain an initial baseline estimate; performing morphological secondary smoothing on the median-smoothed baseline signal to obtain a corrected baseline signal; subtracting the corrected baseline signal from the filtered signal to obtain the baseline-corrected channel signals; and assembling and outputting a multi-channel baseline-corrected signal matrix. This invention can improve the stability and cross-channel consistency of baseline estimation for multi-channel MCC signals, reduce the risk of over-correction and under-correction, and is applicable to multi-channel batch processing scenarios.

This utility model relates to a microscopic observation device for soil particles in shaking table tests, belonging to the technical field of civil engineering experimental equipment. It includes a vibrating base that supports the entire device and provides controlled vibration power; a fully transparent model box is mounted on the vibrating base to hold the soil particle sample to be observed, and the bottom layer of the fully transparent model box has symmetrically arranged wave-absorbing sponge layers on its left and right sides; a miniature camera assembly is mounted on the vibrating base, vibrating synchronously with the fully transparent model box; the miniature camera assembly includes a camera with high-speed continuous shooting capability, and the frame rate of the miniature camera assembly is not less than 300fps; a horizontal electric guide rail is mounted on the vibrating base; and a vertical electric lifting column is mounted on the horizontal electric guide rail. This utility model effectively eliminates the relative displacement problem caused by the asynchronous movement of the camera equipment and the model box in shaking table tests.

The present invention relates to a differential pair noise suppression structure. A circuit board includes at least one substrate having opposite first and second surfaces. A pair of plated vias are disposed along a z-axis. The first surface of the substrate is provided with a first metal line, a second metal line, a first plated via opening, and a second plated via opening to form a differential pair circuit structure. A metal ground is provided on the second surface of the substrate, the metal ground having a blank area. From a projection perspective, the metal ground area encompasses both signal lines to eliminate reflection noise caused by a boundary between the blank area and the metal ground so that the differential pair signal lines have a uniform characteristic impedance.

The application discloses a multi-scale feature fusion neural network phase unwrapping method and system based on De Bruijn stripe coding, first constructs a wavelength-De Bruijn element mapping table; then, the wrapped phase and the background intensity are obtained by using the collected deformation stripes and the background reference map, and the nonlinear cosine component and the phase gradient feature are calculated according to the wrapped phase and the background intensity, so that a multi-channel physical feature input tensor is constructed. Then, the tensor is input into a multi-scale feature fusion neural network with multiple parallel branches. In the training stage, a loss function based on symbol physical wavelength weighting is introduced for constraint. The application directly realizes high-precision prediction of phase order by a deep learning network, does not need additional auxiliary decoding sequence, effectively avoids the complex mathematical principle process and the tedious logic retrieval in the traditional phase unwrapping algorithm, and significantly improves the efficiency of three-dimensional measurement and the robustness to complex environment.