138results about How to "Reduce boundary effects" patented technology

The invention relates to stereo projection systems for displaying stereopaired images on mirror-spherical or parabolic screens and for collectively watching a stereo effect without using stereo spectacles. Said invention makes it possible to continuously dynamically superimpose the projections of the left and right picture frames of a steropair with the user's left and right eyes, respectively. Such impositions are carried out simultaneously and independently for each viewer. The technical result is attainable by that the inventive stereo projection system comprises stereo projectors which are individually allocated to each viewer and in-series connected, a monitoring system for continuously and accurately determining the viewers' eye positions, a self correcting device, video-correcting devices, automatic drives for the mechanical self-correction of the stereo projectors and the system optical elements, units which are used for forming stereopair projected images in the stereo projector and which are coupled with the video-correcting device for the video-correction of the optimal parameters of the screen images. The inventive system makes it possible to carry out the self- and video-correction in an integral manner in such a way that the comfort of the stereo effect viewing is maximally satisfied.

The invention discloses a foundation base model test device capable of bidirectional loading. A force-bearing framework is a rectangular steel frame, a model slot is of a rectangular steel structure, is provided with an upper opening and is formed by welding of a box template, the force-bearing framework is sleeved at the periphery of the model slot, a horizontal actuator counterforce column is vertically erected on the left end part of the model slot, the left end of the horizontal actuator is connected with the horizontal actuator counterforce column, the right end of the horizontal actuator is connected with the top of a pile, the upper end of a vertical actuator is connected with a cross beam at the upper part of the force-bearing framework, the lower end of the vertical actuator is connected with the top of the pile through a vertical dowel steel, a row of drain valves are arranged at the lower part of the left side wall of the model slot, an inlet valve is arranged at the lower part of the right side wall of the model slot, and a water supply pipe of the inlet valve is connected with a constant-pressure water tank. Monitoring is systematic and comprehensive, embedding of monitoring instruments is relatively easy, and automatic and real-time monitoring on multiple physical quantities can be realized. The foundation base model test device disclosed by the invention can be used in conducting model tests like slope foundation, composite foundation and pile foundation.

The invention discloses a comprehensive permeability testing machine for measuring vertical permeability coefficient and horizontal permeability coefficient. The invention comprises a constant-pressure water tank which is communicated with two water supply pipes, wherein, one water supply pipe is communicated with an upper pressure chamber; the top of the upper pressure chamber is provided with a barometer and an air-bleed hole and the side face of the upper pressure chamber is provided with an inflating device; the upper pressure chamber is communicated with a lower pressure chamber through an assembly member; the upper part of the lower pressure chamber is provided with a bubble exhaust hole and the lower part of the lower pressure chamber is communicated with a graduated flask through an exhaust pipe and a metered valve; the other water supply pipe is connected to the left of the assembly member; and the assembly member is communicated with the graduated flask through the exhaust pipe and the metered valve and consists of an impervious membrane, silicon rubber, a V-shaped slot board and a pressurized plastic membrane. The comprehensive permeability testing machine has the advantages that: firstly, the pressurized plastic membrane can quickly, precisely and uniformly transfer normal pressure to a sample, and the impervious membrane can prevent leakage of the sidewall; secondly, water flow is uniformly infiltrated into the V-shaped slot; thirdly, due to arrangement of the silicon rubber, the border effect is reduced; fourthly, the whole machine realizes measurement of the vertical permeability coefficient and the horizontal permeability coefficient, and is precise, simple and clean, highly efficient, practical and convenient to operate.

The invention belongs to a strength testing device and a testing method for a fuselage wall plate under the action of combined loads. The strength testing device for the fuselage wall plate under the action of the combined loads comprises corner boxes, airtight end plates, the fuselage wall plate, a hinge, mandrils, keels and arc-shaped rubber plates, wherein the airtight end plates are arranged at two ends of the fuselage wall plate, the corner boxes are arc-shaped components and installed at a combined part between the airtight end plates and the fuselage wall plate, the keels are arc-shaped frames, the keels are connected in a pasting mode through the arch-shaped rubber plates to form a keel group, the mandrils are installed on web plates at two ends of the keel group, and the hinge is arranged on the fuselage wall plate and the keel group and achieves hinged connection of the fuselage wall plate and the keel group. According to the strength testing device and the testing method for the fuselage wall plate under the action of the combined loads, boundary conditions of the fuselage wall plate can be effectively imitated, the combined loads are conveniently used for achieving a strength test, and due to the fact that drawing loads and compressing loads are not used at the same time, the applied combined loads are one kind of or two kinds of or three kinds of internal pressure loads, drawing loads (or compressing loads) and shear loads.

The invention relates to a large-field soil and solute transporting system and discloses a simulated system for researching leaching, migration and transformation conditions of solutes in the soil under a field irrigation condition. The system comprises a soil groove, a water supply system, a sampling system, a data collecting system and a leaching solution collecting system, wherein the inner wall and the bottom part of the soil tank are provided with waterproof layers and the soil is filled into the soil tank; the water supply system is used for supplying water to the soil tank; the sampling system is used for sampling a solution contained in the soil of the soil tank; the data collecting system is used for monitoring the water content in the soil with the different depths in the soil tank at regular time; and the leaching solution collecting system is used for collecting a leaching solution at the bottom of the soil tank. The system disclosed by the invention can be used for monitoring the leaching, migration and transformation conditions of the solutes in the soil under the field irrigation condition one by one, so that the test period is shortened, the boundary effect is reduced and the test precision is improved; and furthermore, the problems that the indoor evaporation amount is small and does not accord with field conditions are solved by using an evaporation system.

A step type variable speed scanning method for accuracy control of laser bend forming belongs to the technical field of plastic forming. A laser coating material is coated on the scanning area of a surface to be scanned, a sheet material to be detected is clamped on one side, the scanning speed of the scanning area is determined by the diagram method to generate the step type variable speed scanning scheme corresponding to the scanning area, and finally the sheet material to be detected is scanned and processed according to the step type variable speed scanning scheme in a laser numerical control manner. The measure and check after processing are performed after the sheet material is cooled naturally. The method of the invention can effectively reduce the phenomenon of border effect, enhance the forming accuracy of the sheet material, thereby realizing the different energy output of the different heating area to balance the geometric constraint of the sheet material and improve the border effect.

The invention discloses a method for simulating soil slope instability induced by groundwater. The method is characterized by comprising the following steps: a, putting a physical model on a centrifugal machine; b, raising the height of an external water tank, opening a water outlet valve and a water inlet valve, carrying out water seepage into a soil layer according to the thickness of a saturated soil layer and completing the saturation process of a soil mass; c, closing the water inlet valve, reducing the height of the external water tank, improving the centrifugal acceleration to solidifyand disperse the internal pore water pressure of the physical model; d, after the solidification is finished, opening the water inlet valve, raising the height of the external water tank to the corresponding height according to the preset water level height of an internal water tank; obtaining different infiltration capacity of the water to the slope when the water in the internal water tank seepsinto the soil layer and stays at different heights, and observing the wetting front change and the slope deformation condition of the physical model. The method disclosed by the invention has the advantages that the height of the groundwater level can be accurately adjusted in real time and washing of water current to the slope body is prevented; in the whole test process, high operability, highreliability and good test effect are realized.

The invention discloses a multi-scene target tracking method based on an adaptive depth feature filter. The method comprises the following steps of converting a target area of an original image into acolor naming space from an RGB space to reduce the interference of color changes, then, calculating a foreground probability graph of a target area, t and training by using the features extracted from the foreground area according to the foreground probability graph to alleviate the boundary effect and effectively inhibit the noise in the background, so that the method can adaptively extract thetarget features. According to the method, multiple layers of depth features are used for training in corresponding related filters respectively; and the weight of the corresponding depth feature filter is updated adaptively according to the tracking effect, the filter stability, the historical response and other information, and the tracking model is guided to adaptively select useful depth features in different scenes, so that the target can be tracked in a robust manner in various complex scenes. Compared with the prior art, the method has the advantage of high robustness, and can accurately track the target in various complex scenes.

A method for achieving high sub-unit accuracy during global motion estimation of sequential video frame images is described herein. The method estimates the global motion using an existing phase-correlation approach, and further refines it to a sub-unit level using the neighborhood values of the phase correlation surface peak The method determines the sub-unit displacement direction by examining the signs of the peak of phase correlation surface and its two nearest neighbors. The method determines the sub-unit displacement magnitude by applying the ratio of associated phase correlation values to a 5^th-order polynomial function. The method then computes the actual motion by adding the sub-unit displacement value to the global motion value as calculated by the phase-correlation approach.

The invention discloses a laminar shear box device for a supergravity-field vibration table test. A main body is a shear box formed by laminating 20 layers of rectangular aluminum alloy frames of equal thicknesses; the layers are connected with one another through a rolling shaft; horizontal displacement sensors are arranged on the upper 19 layers through bolts; the periphery of a shear frame is provided with a rigid support frame, which comprises a displacement sensor fixture, a guide post and a static post; the guide post and a top plate are provided with frame guide wheels; a rubber film is arranged on the inner side of the shear box; a drainage system is arranged in a bottom plate of the shear box; and the bottom plate is fixed on a vibration table during testing. In the invention, the behavior of a semi-infinite site soil body can be simulated through a model of a definite size. The laminar shear box device has the characteristics of simple structure and convenience for installing and applying.

Described is a system for detecting multiple salient objects in an image using low power hardware. From consecutive pair of image frames of a set of input image frames, image channels are generated. The image channels are resized into multiple image scales that specify a relative size of a salient object in the image frames. A patch-based spectral transform is applied to overlapping image patches in the resized image channel, generating salient patches. Saliency patches are combined into a saliency map for each resized image channel, resulting in multiple saliency maps. The saliency maps are combined into an aggregate saliency map. An adaptive threshold is applied to the aggregate saliency map to determine which pixels in the aggregate saliency map correspond to a detected salient object region including a salient object. An object bounding box is generated for each salient object and output to a display.

The invention provides an MRI image inhomogeneity correction method based on regularization. A lowpass filtering method is improved, part of an area with low grey-value difference is selected and is subjected to lowpass filtering to obtain an initial estimate for a inhomogeneous field, and then extrapolation is performed through a regularized polynomial fitting method to obtain an estimate for an inhomogeneous field of a whole image. According to the method provided by the invention, an area-of-interest is determined and is subjected to filtering, so the boundary effect in the global image filtering method can be avoided, and fitting is performed through a regularization method, thus overfitting is guaranteed not to happen under the condition of improving the fitting order.

The present invention relates to an instantaneous frequency extraction method of Doppler signals, and belongs to the signal processing technology field. According to the present invention, for the Doppler signals outputted by various interference velocimeters, firstly the appropriate parameters, such as the wavelet, the threshold type, the decomposition layer number, the vanishing moment, etc., are selected to carry out the wavelet de-noising on the output signals to smooth the edges; after then the amplitude modulation-frequency modulation decomposition is carried out on the de-noised signals in an iteration manner, and the envelopes of the signals are extracted and are normalized; and finally, the instantaneous frequencies of the normalized signals are extracted by a direct orthogonal method, and an estimation curve of the instantaneous frequencies is obtained in a least-square fitting manner. According to the present invention, firstly the signals are de-noised, so that the direct orthogonal method which is more sensitive to the noise originally can be applied to the Doppler signals, and the simulation results show that on the condition of selecting the appropriate parameters, an error of an instantaneous frequency value obtained by the present invention and a theoretical value is less than 0.5%, the calculation time and the sampling point number are positively related, and the calculation velocity is faster.

The invention belongs to the technical field of communication, and discloses a method and a device for correcting audio signals. The method comprises the following steps: intercepting a segment of signal near the boundary of an audio signal data frame; subjecting the intercepted signal to linear treatment to obtain a new signal; and calculating the evaluation index of the new signal and, if the evaluation index is smaller than a preset evaluation index, continuing the linear treatment until the evaluation index of the signal after the linear treatment is larger than or equal to the preset evaluation index. The method has the advantages that the method has less calculation amount, can achieve smooth and periodic time domain waveforms of the audio signal by correcting the audio signal, and can ensure the phase information of the signal and reduce frequency spectrum divergence, thereby achieving smooth frequency spectrum and further eliminating boundary effect.

The invention discloses a satellite video dynamic target tracking method fusing a correlation filter and motion estimation, and relates to the field of spaceflight earth observation information processing and analysis. The satellite video dynamic target tracking method comprises the steps: obtaining a satellite video, and segmenting the satellite video into continuous single-frame images; selecting a to-be-tracked target from the single-frame image, constructing image features of the target, and inputting the image features into a related filter to obtain the position of the target; performingmotion estimation processing on the position of the target through a trajectory average algorithm and a Kalman filter, and when the Kalman filter is not stable, taking the processing result of the trajectory average algorithm as a motion estimation result; and when the Kalman filter is stable, taking a processing result of the Kalman filter as a motion estimation result. The satellite video dynamic target tracking method is suitable for satellite video ground target tracking, especially when the target is shielded, can still effectively track the target, and can complete multiple applicationssuch as target high-precision tracking, sensitive target real-time positioning and traffic flow monitoring.

A charging circuit for charging/biasing high impedance loads such as capacitive loads. The circuit comprises an input for connecting to a voltage/charge source and an output for connecting to the load. A capacitor is connected between the output and a reference voltage such as ground and a reverse bias diode is connected between the input and the output terminals. The reverse bias diode is arranged to allow a reverse current to pass which is sufficient to compensate for current leakage at the output terminal or other parts of the circuit. The reverse bias diode is conveniently a polysilicon diode. The diode may be connected in parallel with a shunt device to allow for rapid charging during start up.

The invention discloses a protective cover based on double-sided explosive welding and a charging structure. The protective cover can be repeatedly used and mainly comprises an outer shell, a buffer layer and a constraint net. The protective cover provides a closed environment for explosive welding, can effectively prevent an upper-layer composite plate and fragments from flying apart, reduces noise pollution and dust pollution and provides a safe and comfortable working environment for explosive machining. The charging structure comprises a constraint box, supporting shells and an explosive. The supporting shells are columnar shells shaped like the Arabic number '8' and evenly distributed along the inner surface of the constraint box, achieve a supporting effect, and enhance detonation at the boundary, thereby reducing the boundary effect. The upper surface and the lower surface of the charging structure are in fit with the upper-layer composite plate and a lower-layer composite plate, and the explosive is in a constraint state in any direction. Accordingly, the explosive detonation critical thickness is reduced, and the energy utilization rate is improved.

The invention relates to a real-time evaluation method of human body motion sequences. Boundary extension is carried out on the motion sequences by employing interpolating wavelet based on difference, thereby reducing boundary effect; a wavelet coefficient is calculated, thereby obtaining key frames; features of the motions are described through the key frames; the distance between two motion sequences is calculated by employing a DTW distance measurement function; finally the distance is normalized, thereby obtaining a similarity score of the two motions. The method has the advantages that the boundary effect is reduced by employing the interval interpolating wavelet, thereby obtaining the more accurate key frames, and further the more accurate motion evaluation is realized.

The invention discloses a depth correlation target tracking algorithm based on mutual reinforcement and multi-attention mechanism learning. The algorithm comprises the following steps: inputting a previous frame of target area and a next frame of search area; initializing parameters of the feature extractor, learning the parameters of the feature extractor through gradient descent through mean square error loss, and extracting features from the search area through the feature extractor; calculating autocorrelation of the features, and learning a filter template through a ridge regression closed solution; enabling the next frame to determine a search area through a target position speculated by the previous frame, carrying out feature extraction through a designed feature extractor, and calculating cross-correlation of features of the target area and the search area; carrying out related operation on the characteristics and a filter template, wherein the maximum value in the output values is the latest position of target tracking; and each frame learns and updates the target filter template.

The invention discloses a loose media permeation grouting simulation experiment method. A constant-pressure confining pressure pump is utilized to inject high-pressure water into a rubber water bag sleeve via a water hole to provide confining pressure, and the provided confining pressure is higher than grouting pressure; during grouting, a rubber valve sleeve depends on the confining pressure to tightly wrap loose media, loose media grouting is definitely permeation grouting under the condition that the confining pressure is higher than the grouting pressure, and therefore the influence of grouting methods, such as compaction grouting and fracturing grouting, on grouting effect is prevented. The loose media permeation grouting simulation experiment method is convenient to operate, and cantruly simulate permeation grouting reinforcement for the loose media, the rubber valve sleeve is utilized to wrap the loose media, and by means of the rubber water bag sleeve, pressure is applied on the loose media to simulate a geostress environment; by regulating the pressure of the constant-pressure confining pressure pump and a grouting pump, the confining pressure is higher than the groutingpressure, so that the loose media permeation grouting process can be simulated; after grouting is completed, the solidified loose media wrapped by the rubber valve sleeve can be completely taken out for study; and an experimental result obtained by the method has guiding significance for an actual engineering design.

The invention discloses a discrete element modeling method for a rock and earth mass triaxial test taking film effect. The method includes following steps: S1, modeling a sample preparing container; S2, modeling a rock-earth mass sample; S3, endowing the generated rock-earth mass sample with material attribute of given sample units, balancing stress among the sample units to complete making of the rock-earth mass sample; S4, building an elastic film, replacing a rigid barrel of a sample preparing container model with the elastic film, setting corresponding material attribute for the elastic film to complete building of a triaxial test discrete element model. Further, the invention further discloses a numerical simulation method based on the discrete element model. According to given pressurizing conditions, stress loading is adopted to axially pressurize the rock-earth mass sample, and lateral confining pressure is applied on the rock-earth mass sample through water pressure. A film unit is adopted to simulate a latex film in the triaxial test, and flexible boundary of the latex film better conforms to actual circumstance of indoor triaxial test numerical simulation.