36results about How to "Address boundary effects" patented technology

The invention is applied to the sea engineering field, and provides a deep sea standpipe segment model bidirectional forcing vibration experimental apparatus under an effect of an oblique uniform flow. The apparatus comprises a deep sea standpipe module, a first end prosthese module, a second end protheses module, a first horizontal sliding module, a second horizontal sliding module, a first vertical sliding module, a second vertical sliding module and a measurement analysis control module, wherein, two ends of the deep sea standpipe module connect with the first end prosthese module and the second end prostheses module respectively, the first vertical sliding module connects with the first end prosthese module and the first horizontal sliding module respectively, the second vertical sliding module connects with the second end prosthese module and the second horizontal sliding module respectively, the first horizontal sliding module is fixedly connected with a bottom of a trailer, the deep sea standpipe module is installed to form a certain angle with the first vertical sliding module and the second vertical sliding module, and the measurement analysis control module is installed on the trailer and is connected with the two end prosthese modules, two vertical sliding modules and two horizontal sliding modules. In the invention, a large scale standpipe segment is employed, thus an experimental Reynolds number is in a 106 range to avoid a scale effect. According to the experimental apparatus disclosed in the invention, bidirectional force movement is employed, a special ocean condition that an inflow is not perpendicular to a standpipe is simulated, a standpipe vortex induced vibration form is simulated factually, and end prosthese is employed to solve a problem that two sides of a model appear a boundary effect in an experiment.

The invention discloses a wavelet progressive data compression method, which is used in the wireless sensor network. A cluster head carries out the wavelet transformation and generates the wavelet coefficient while receiving the sensor data; when the wavelet coefficient reaches one data unit, the cluster head carries out the coding compression and transmits the coding compression result, the wavelet coefficient continuously generated by the cluster head forms the next one data unit, the operation is circularly carried out for forming the progressive data compression transmission. The invention solves the problem of the mismatching between the cluster head storage capacity and the sensor data quantity in the wireless sensor network, and the boundary effect brought by the wavelet transformation. The invention is suitable for the sensor network model based on the clustering.

The invention is suitable for the field of the oceanographic engineering and provides a bidirectional forced vibration experimental apparatus for a deep sea riser segment model under the action of uniform flow. The bidirectional forced vibration experimental apparatus comprises a deep sea riser module, end part prosthesis modules, horizontal sliding modules, vertical sliding modules and a measurement analysis control module, wherein both ends of the deep sea riser module are respectively connected with the end part prosthesis modules; the vertical sliding modules are respectively connected with the corresponding end part prosthesis modules and the corresponding horizontal sliding modules; the horizontal sliding modules are fixedly connected with the bottom of a trailer; and the measurement analysis control module is arranged on the trailer and is connected with the end part prosthesis modules, the horizontal sliding modules and the vertical sliding modules. In the invention, large-scale riser segments are adopted, so that a test Reynolds number is in the range of 106 for avoiding the scale effect; the double freedom degree forced movement is adopted to truly simulate the vortex-induced vibration form of a riser; and meanwhile, due to the adoption of end part prosthesis, the problem of the boundary effect at both sides of the model in an experiment is solved.

A method for measuring microcosmic dynamic properties of each compositive phase in a multiphase material comprises the following steps that: (1) a multiphase material sample to be measured is prepared; (2) one or a plurality of test areas are selected on the surface of the sample to be measured randomly to perform the nanometer pressing-in test, test points are arranged in a way of grid, grid nodes and impressing points are put into a one-to-one correspondence; (3) the test result is analyzed initially to get E-hardness H data pairs of available elastic modules with the number of Ne, a scattergraph is drawn in a data summarization list or in an E-H rectangular plane coordinates system; (4) the effective data points with the number of Ne are sorted, the data group and the compositive phases are in a one-to-one correspondence; (5) the volume fraction and the microcosmic dynamic properties of each compositive phase are determined according to the data group. Therefore, each compositive phase content, the elasticity modulus and the hardness of the multiphase material can be measured conveniently and flexibly; the measure result is intuitive and reliable, thereby being particularly suitable for the measurement of the microcosmic dynamic properties of each compositive phase in the multiphase materials such as the multiphase steel, the polymer, the biological materials and the composite materials, etc.

The invention discloses a space-time channel constraint correlation filtering tracking method based on suppressible abnormity. The method comprises the steps of S1, extracting HOG features, first depth features and second depth features of a t-th frame; S2, performing fusion processing on the HOG feature, the first depth feature and the second depth feature to obtain a first fusion feature X, anddetermining the position and the scale of a target in the t-th frame of image based on the first fusion feature X and a filter; S3, according to the feature map of the t-th frame, updating the filterbased on a space-time channel constraint related filtering model capable of suppressing abnormality; and S4, repeating the step S2S4 until all frames are tracked, and finally obtaining a tracking result. According to the method, the feature representation capability of the target template is remarkably improved by combining manual features with depth features, self-adaptive channel feature selection is realized through l2, 1 norm, and the problems of boundary effect and background clutter are effectively solved.

The invention provides an oblique uniform flow deep sea pipeline segment model bidirectional forced vibration experiment apparatus which comprises a deep sea pipeline module, prosthesis modules, horizontal slide modules, vertical slide modules, a measurement analysis control module and a false bottom module. Two ends of the deep sea pipeline module connect with the end prosthesis modules. The vertical slide modules connect with the end prosthesis modules and the horizontal slide modules. The horizontal slide modules are fixedly connected with a bottom of a trailer. The measurement analysis control module is provided on the trailer, and connects with the end prosthesis modules and two slide modules. The prosthesis modules are fixedly connected with the trailer. According to the invention, through setting a false base plate, a surface effect of a seabed can be simulated; mutual coupling of pipe fittings and a flow field; vibration of two degrees of freedom of forward flow and vertical inflow are considered, and condition of forming a certain inclination between inflow and pipe fitting axis is realized; an experimental condition can reach an actual Reynolds number range.

The invention discloses a testing device for simulating self-oscillation under mutual interference of two stand column models under uniform flow. The testing device obtains velocity and stress of a cylinder body through measuring, obtains actual motion response signals under the effect of water flow by solving a motion equation of the cylinder body and exerts the actual motion signals onto the models through a servo motor to enable the models to move, so that self-oscillation motion is simulated. During test, a horizontally sliding module is used for simulating flow, and a vertically sliding module is used for simulating vortex-induced vibration in the vertical direction. The device sets parameters to simulate model structure performance, avoids messy testing operations in a traditional self-oscillation device, accelerates testing progress, provides large freedom degree to the model selection, simulates special working conditions of self-oscillation under mutual interference of two stand columns, adopts a large-scale stand column subsection to reduce scale effect, and adopts an end prosthesis device to solve the problem of model boundary effect.

The invention provides a bidirectional forced vibration experimental apparatus for a FISHFRAM buoy segment model under the action of inclined uniform flow, which comprises a buoy segment module, prosthesis modules, horizontal sliding modules, vertical sliding modules and a measurement analysis control module. Both ends of the buoy segment module are respectively connected with the end part prosthesis modules. The vertical sliding modules are respectively connected with the corresponding end part prosthesis modules and the corresponding horizontal sliding modules. The horizontal sliding modules are fixedly connected with the bottom of a trailer. The measurement analysis control module is connected with the buoy segment module, the prosthesis modules, the horizontal sliding modules and the vertical sliding modules. In the invention, the forced vibration can be carried out in two directions; the local stress of a fishing net can be measured; by arranging component balances inside the buoy module, the overall stress of the fishing net can be measured; by arranging component balances outside the buoy module, the overall stress of the fishing net and the buoy module can be measured; due to the adoption of the special end part prosthesis module devices, the problem of the boundary effect of the model is solved; and the test condition can reach an actual KC value range, the scale effect is avoided, and a certain included angle can be formed between the bidirectional forced vibration experimental apparatus and incoming flow so as to effectively simulate the special working condition.

The invention provides a large soil-structure interaction test box. A box body is arranged on a base and comprises a plurality of layers of body frame sections arranged in a stacked mode and a top frame section, wherein each body frame section and the top frame section are each a frame body which is defined by sequentially connecting a pair of opposite cross beams and a pair of opposite longitudinal beams; and rolling plates are arranged on the cross beams of the body frame sections, and balls are arranged on the rolling plates. An accommodating cavity is formed by the box body and the base, and the inner wall of the accommodating cavity is lined with an anti-leak layer. Stiffeners are arranged on the outer surfaces of the longitudinal beams, and a plurality of screw holes are formed in each stiffener. Vertically-arranged round steel rods are arranged on the outer sides of the longitudinal beams and screwed into the screw holes through fixing strips and bolts. According to the large soil-structure interaction test box, the round steel rods are arranged on the side faces of the box body and can be detached, and the installation positions of the round steel rods can be flexibly changed so that the rigidity of the box body can be changed by selecting different numbers of round steel rods with different diameters and different installation positions of the round steel rods. Since the round steel rods have the same rigidity in any direction in the horizontal plane, the round steel rods can provide the same rigidity in any direction of the horizontal plane for the box body.

The invention is suitable for the field of ocean engineering and provides a deep-sea riser segmented model forward flow forced vibration experimental device under the action of uniform flow. The deep-sea riser segmented model forward flow forced vibration experimental device comprises a deep-sea riser module, end part false body modules, a fixing module, a sliding module and a measurement analysis and control module, wherein the two ends of the deep-sea riser module are connected with the end part false body modules respectively; the fixing module is connected with the end part false body modules and the sliding module respectively; the sliding module is fixedly connected with the bottom of one end of a trailer truck; and the measurement analysis and control module is arranged on the trailer truck, and is connected with the deep-sea riser module, the end part false body modules and the sliding module respectively. The invention aims to solve the problems that the conventional experimental device can only be used for simulating sea conditions with low Reynolds numbers and boundary treatment is not performed on riser segments; a riser model with an appropriate slenderness ratio is selected, so that the practical Reynolds number of 106 can be reached, and the scale effect is avoided effectively; and a flow field is simulated through false bodies, so that the problem of boundary effects on both sides of the model is solved.

The invention discloses a node sleep scheduling method and system comprehensively considering network coverage and energy efficiency, and the method comprises the steps that: the own scheduling priority of a node is calculated through the network coverage and residual energy, and a message containing the scheduling priority in a neighbor node set is transmitted and received; any node si divides neighbor nodes of the node si into two groups of nodes of an LSN and an HSN; firstly, a node si judges whether the coverage rate of neighbor nodes in an LSN group to the node si meets a threshold value theta or not; if yes, the node si broadcasts sleep message and enters a dormant state; otherwise, the node si randomly waits for a period of time and monitors the active message sent by the neighbor node in the HSN group; then, the node si continuously judges whether the coverage rates of the neighbor nodes in the LSN group and the neighbor nodes in the working state in the HSN group on the node si meet a threshold value theta or not; if yes, the node si broadcasts sleep message and enters a dormant state; and otherwise, the node si broadcasts the active message and enters a working state.