42 results about "Cylindrical array" patented technology

The invention discloses a high-frequency shallow water bottom reverberation signal modeling method, and belongs to the technical field of underwater acoustic engineering and signal processing. The method comprises the following steps: setting a modeling hypothesis; a cylindrical array geometric structure is constructed, scattering units are divided, and channel parameters and scattering functions are obtained in combination with a Bellhop tool and a GABIM model; generating a reverberation signal time domain expression, deducing an array receiving signal spatial domain expression and calculating a spatial spectrum; the model can also adjust underwater environment parameters to realize simulation under different conditions, and performs time domain and space domain theoretical analysis on reverberation signals based on a cylindrical array. Multi-dimensional underwater environment parameters are fused, and the modeling precision is improved; a receiving and transmitting combined cylindrical array is adapted, and spatial gain is embodied; experiments prove that the average error is within 3dB, the practicability is outstanding, support can be provided for design and optimization of the sonar system, and the method is suitable for underwater reverberation signal simulation and characteristic analysis of the sonar system in the high-frequency shallow water environment.

The invention discloses a PINN-based infrared window surface anti-reflection micro-nano structure optimization design method, which is oriented to a sub-wavelength microstructure (such as a square column array or a cylinder array) on the surface of an infrared optical window, and comprises the following steps of: integrating physical constraints into a neural network model; and high-precision prediction of the reflectivity of the micro-nano structure and intelligent optimization of structural parameters are realized. Aiming at the characteristics of data scarcity and high dimension of design parameters, the invention provides innovative designs such as a parameter space sampling strategy, a PINN model architecture, a physical constraint fusion strategy and a training optimization method, and can effectively solve the problems of long time consumption, large data demand, poor model generalization performance and the like of a traditional design method. And infrared anti-reflection micro-nano structure parameters which meet physical rules and are excellent in performance can be obtained under the condition of less simulation data. According to the technical scheme, intelligentization and high efficiency of infrared window anti-reflection micro-nano structure parameter design are achieved.

According to the method, a universe control equation set comprising a control equation, a free surface, upper and lower layer fluid interface continuity, structure-fluid interface continuity and fluid interface and seabed constraint conditions is constructed, and a vertical-horizontal decoupling modal analysis technology is combined, so that a multi-body radiation coupling model of the bottom-supported cylindrical array with relative motion between columns is provided; an intrinsic mode expansion technology is adopted to synchronously represent a joint radiation mechanism of a surface gravity wave and an internal wave, potential function space transformation and mode matching under a multi-column coordinate system are realized through a Graf addition theorem, and a radiation matrix coupling model considering a bottom-supported boundary constraint is constructed. According to the method, the wave-column coupling effect of the density layered interface can be accurately analyzed, a multi-column interference energy transfer path is quantified, and the modal truncation error is remarkably reduced.

The invention discloses a method for realizing a multi-polarization high-numerical aperture Laplace differentiator based on a metasurface, and belongs to the technical field of micro-nano photonics, optical simulation calculation and light field regulation and control. The single-layer metasurface is composed of a cylindrical array which is made of an amorphous silicon material and has a hexagonal lattice period. Geometric parameters of a silicon cylinder are designed and selected, so that the metasurface excites resonance spectrums with large-angle dispersion capability under illumination of p polarized light and s polarized light in the same working wavelength range, and an optical transfer function required by optical Laplacian differential operation with broadband and high numerical aperture is realized in a real airspace; and Laplacian operation can be executed under non-polarized light and non-coherent light conditions. And generating a processing file of the corresponding metasurface according to the determined geometric dimension of the silicon cylinder unit. And processing the dielectric metasurface by adopting a micro-nano processing technology of electron beam etching. In a working wave band, the metasurface can directly obtain two-dimensional second-order edge contour information of a target image under various illumination conditions.

The invention provides a laser fuze emission beam-expanding optical lens in an extremely simple form, and the optical lens comprises an emission lens which is located at the rear end of the lens and is used for carrying out the small-angle compression shaping of a beam divergence angle of a meridian-direction Gaussian beam emitted by a laser; and the wave mirror is positioned at the front end of the lens and is used for carrying out large-angle beam expansion on the beam divergence angle of the Gaussian beam emitted by the laser in the sagittal direction and realizing uniform shaping of light spots. Strip-shaped distribution shaping is carried out on Gaussian beams of the laser through the extremely simple form of the two lenses, so that the light beam emergent view field in one direction, namely the meridian direction, is compressed to 1 degree, and the light beam emergent view field in the other vertical direction, namely the sagittal direction, is expanded to 90 degrees. By adopting the special element design of the cylindrical surface array, the uniform energy distribution of the whole strip-shaped light spot is realized, the target detection precision of the surface-air laser fuze in a large-range space region is greatly improved, and meanwhile, the extremely simple design is more beneficial to meeting the requirements of miniaturization and low cost.

The application provides a cylindrical array sonar system and a target detection method based on high-resolution beam forming. The method comprises the following steps: converting a beam forming weight vector of a received sound wave signal into a Kronecker product, combining a joint probability density model to construct a negative log-likelihood function, and optimizing a vector in an azimuth dimension and an elevation dimension through a preset direction constraint condition to form a high-resolution beam; performing correlation analysis on echo signals reflected by a target at different azimuth angles and elevation angles and on transmitted sound wave signals at different time delays; constructing a three-dimensional matrix containing a distance, an azimuth angle and an elevation angle according to a correlation analysis result, performing normalization processing on the three-dimensional matrix to eliminate signal intensity differences, and outputting a target detection positioning result. Through the combination of Kronecker integral decomposition and three-dimensional matrix modeling, the application realizes high-resolution joint positioning detection of a target in an azimuth angle, an elevation angle and a distance dimension, effectively eliminates signal intensity differences, and improves positioning accuracy.

The invention discloses a method for calculating the mass of attached water of a multi-cylinder array system. The method comprises the following steps: solving the velocity potential of a flow field when a single cylinder vibrates in water; according to the velocity potential of the flow field when the single cylinder vibrates in the water, solving the velocity potential of the flow field when the double cylinders vibrate in the water; according to the velocity potential of the flow field when the double-cylinder vibrates in the water, solving the hydrodynamic force borne by the double-cylinder when the double-cylinder vibrates in the water; according to the hydrodynamic force borne by the double cylinders when the double cylinders vibrate in the water, the hydrodynamic force borne by any single cylinder when the multiple cylinders vibrate in the water is solved; and calculating the mass of the attached water of any single cylinder according to the hydrodynamic force borne by the single cylinder when the multiple cylinders vibrate in the water. Based on the potential flow theory, the invention provides the multi-cylinder array system attached water calculation method which is high in accuracy, accurate and reliable, and the accuracy and efficiency of engineering design are improved.

The invention relates to a cylindrical array fin evaporator, the evaporator comprises an evaporator upper plate and an evaporator lower plate, the evaporator lower plate is provided with a fin array, the fin array is cylindrical, and the evaporator upper plate comprises an inlet, a working medium shunting section, a manifold drainage plate, a working medium converging section and an outlet; the cylindrical array fins are located in the middle of the evaporator lower plate and extend upwards, and the positions of the cylindrical array fins correspond to the positions of the manifold drainage plates in the evaporator upper plate. The novel manifold evaporator is arranged, the cylindrical array fins are adopted in the manifold evaporator, the working medium can flow along the fins, and the heat exchange efficiency of the new energy automobile thermal control system is further improved.

According to the method, a surface gravity wave and inner interface wave velocity potential field is analyzed into a product form of a vertical characteristic item and a horizontal diffraction field, and dimensionality reduction solution of a three-dimensional wave problem is realized; a vertical characteristic function orthogonal system meeting free liquid level, seabed boundary and interface coupling conditions is constructed, horizontal diffraction potential is decomposed into an incident field, a local column and an adjacent column scattering effect, and a Bessel function addition theorem is applied to construct a closed linear equation set of a multi-column interference field; establishing an extended dispersion equation containing density spring layer parameters, and revealing a modulation rule of layered strength on complex wave propagation characteristics; and finally, through tensor product coupling of a vertical mode and a horizontal diffraction field, constructing a full-three-dimensional diffraction velocity potential analytical solution, synthesizing a cross-layer pressure field integral by adopting a domain decomposition technology, and establishing a multi-column array generalized wave excitation force forecasting model. According to the method, efficient analytical calculation of the wave load of the multi-column system in the layered fluid is innovatively achieved.

The broadband bidirectional absorption type common-mode filter comprises a first port, a first absorption circuit, a phase delay circuit, a second absorption circuit and a second port which are connected in sequence, each of the first port and the second port comprises a reference ground I, a first metal cylinder array, a first metal ground layer and a first dielectric plate which are connected in sequence; a port coupling microstrip line is etched in the middle of the upper surface of the first dielectric plate; each of the first absorption circuit and the second absorption circuit comprises a reference ground II, two first metal cylinders, a first transmission line, a second metal cylinder, a second transmission line and a second dielectric plate; a first differential coupling microstrip line is etched on the upper surface of the second dielectric plate; one end of the second transmission line is also provided with a resistor; the phase delay circuit comprises a reference ground III, a second metal cylinder array, a second metal ground layer and a third dielectric plate which are connected in sequence; a second differential coupling microstrip line is etched on the upper surface of the third dielectric plate; the invention has the advantages of low manufacturing cost, bidirectional absorption and broadband characteristics.

The application relates to a low-sidelobe transmitting and receiving beam forming method based on a cylindrical array, which is used for solving the problem of high sidelobe level of the existing cylindrical phased array radar. The application utilizes the cylindrical array to decouple the cylindrical array into a uniform linear array in the elevation direction and a uniform circular array or a circular arc array in the azimuth direction at a certain beam pointing direction, and performs low-sidelobe processing on the elevation direction and the azimuth direction respectively during transmitting and receiving beam forming, so that the low-sidelobe effect of the whole array is realized, wherein the transmitting beam adopts only phase weighting, and the receiving beam adopts amplitude and phase weighting.

A conformal array beamforming method based on the maximum SNR criterion comprises the following steps: (1) establishing a global coordinate system model for the conformal cylindrical array; (2) establishing a local coordinate system for each array element using Euler coordinate transformation; (3) calculating the element amplitude gain of each element based on the signal incident angle under the local coordinates and the element radiation pattern; (4) calculating the element activation threshold condition and determining whether the element is activated based on the element activation gain; (5) achieving the maximum SNR array output based on the element activation determination result. This invention can achieve the maximum SNR output of a conformal array of a certain size with incident signals at any angle, and the algorithm is simple. This invention can be applied to fields such as communication and radar.

The invention discloses a mixed wettability nanowire modified three-stage enhanced boiling heat transfer structure and a preparation method thereof, and belongs to the technical field of micro-nano processing and enhanced phase change heat transfer. According to the structure, two kinds of functional micro-column arrays, namely a micro-cylinder array modified by a super-hydrophilic nanowire and a micro-square column array modified by a super-hydrophobic nanowire, are integrated on a substrate. An efficient liquid supplementing channel is constructed through the strong capillary action, and local dryness is effectively inhibited; the latter is used as a low-superheat-degree nucleation site, rapid generation and separation of bubbles are promoted, bubble coalescence can be effectively inhibited through the millimeter-level spacing, and formation of a steam film is delayed. The two types of micro-columns are orderly distributed in space, and a bubble separation path and a liquid backflow channel are collaboratively optimized. The structure integrates the multi-scale enhanced boiling heat transfer advantages of the millimeter-scale hydrophobic nucleation interval, the micron-scale cylinder and the nano-scale linear structure, the heat transfer coefficient and the critical heat flux are improved, and the structure has important application potential in the high-heat flux heat dissipation fields of high-power electronic devices, aerospace, new energy equipment and the like.

According to the method, a multi-modal analytical model with the effects of surface waves and internal waves is established aiming at the density stratification phenomenon caused by gravity settlement and solar radiation heat effect in ocean engineering; a three-dimensional layered fluid global control equation set is constructed, a hyperbolic function combined vertical characteristic function piecewise expression is adopted to accurately characterize fluid bimodal propagation characteristics, a double-layer fluid bimodal dispersion equation is combined, a multi-body coupling matrix equation is introduced to process an inter-column wave scattering effect, and a multi-body coupling matrix equation is introduced to process the inter-column wave scattering effect. Cylindrical wave function coordinate transformation is realized by applying a Graf addition theorem, and a hydrodynamic integral expression containing additional mass and radiation damping is constructed based on a modal superposition principle. According to the method, the limitation of a traditional single-layer fluid model is broken through, the wave interference energy distribution rule under the surface wave-internal wave combined action is quantitatively analyzed, and the radiation force calculation precision and the engineering prediction applicability of the dense cylinder array in the complex marine environment are remarkably improved.

The application discloses a ship radiation noise measuring system and a double-layer cylindrical array measuring device, wherein the cylindrical array measuring device comprises a circular bottom support plate, a circular top support plate, a support pipe, a group of hydrophone oscillators, a ranging transducer, a support base and an electronic cabin; opposite ends of the support pipe are respectively installed in the middle of the bottom support plate and the middle of the top support plate; opposite ends of the hydrophone oscillators are respectively installed in the circumferences of the bottom support plate and the top support plate; the ranging transducer is installed on the top support plate; the support base is installed below the bottom support plate; the electronic cabin is installed below the bottom support plate and is surrounded by the support base; and each hydrophone oscillator is connected to the electronic cabin.

The utility model relates to the technical field of test fixtures, and particularly discloses a medical transducer test fixture which comprises a positioning shaft, a cylindrical array transducer is placed at the large cylindrical end of the positioning shaft, a fixing plate is fixedly connected to the outer side of the positioning shaft, and a supporting ring is fixedly connected to the end, away from the positioning shaft, of the fixing plate. A clamping assembly for clamping the cylindrical array transducer in the positioning shaft is arranged between the supporting ring and the positioning shaft; according to the medical transducer testing clamp, positioning of a transducer in the circumferential direction is achieved through the regular polygon inner hole, then the axial position of the transducer is accurately positioned through the adjustable mandrel, the clamping force of the clamping assembly is adjusted, the clamping force of the clamping assembly is adjusted, and the testing efficiency of the transducer is improved. A wedge-shaped chute mechanism is adopted to realize the normal displacement of a contact along each surface of the regular polygon and cylindrical array transducer, so that the purpose that the contact contacts and is separated from a bonding pad is achieved.

The utility model provides a kind of shell dismantling tool with fixed structure and anti- indentation contact surface, it is related to semiconductor device processing equipment technical field, the shell dismantling tool includes tool upper cover, tool base and press equipment connecting mechanism;Tool upper cover bottom is provided with rectangular boss and rectangular contact surface, rectangular contact surface is contacted with product copper bottom plate surface;Tool base surface is equipped with the positioning cylinder array matched with product bushing, and positioning cylinder array includes at least four convex positioning columns;Press equipment connecting mechanism includes the first threaded hole group being set in tool upper cover top and the second threaded hole group of tool base bottom, and first threaded hole group and second threaded hole group are respectively connected with press equipment executing mechanism rigidly by upper cover peg and base peg;Buffer pad is also provided on the working surface of tool base, is fixed by dovetail groove connecting structure, solves product copper bottom plate scratch, product DBC broken horn, and the problem that copper bottom plate is difficult to take from press tool inside.

The utility model relates to the technical field of cylindrical array oscillation stopping barrels, and provides a catamaran underwater measurement cylindrical array oscillation stopping barrel which comprises an oscillation stopping barrel body, a lifting assembly, a stabilizing rod, a stabilizing assembly, a positioning rod and a clamping assembly, the oscillation stopping barrel body is fixedly installed in a circular groove of a connecting block, the lifting assembly is arranged on the connecting block, a cylindrical array is arranged on the lifting assembly, and the stabilizing assembly is arranged on the cylindrical array. The connecting block is used for driving the cylindrical array to ascend and descend and detecting the interior of water, the two stabilizing rods are fixedly installed on the two sides of the cylindrical array respectively, the stabilizing assembly is arranged on the connecting block, the two positioning rods are arranged on the stabilizing assembly, and the two clamping assemblies are arranged on the positioning rods. According to the technical scheme, the problem that in the prior art, in the process that the cylindrical array ascends and returns to the swing stopping barrel, when the cylindrical array shakes in the ascending process, the two sides of the ship body still can be collided is solved.

The invention discloses a manufacturing method of a double-side cylindrical surface array convex lens, and relates to the technical field of precise optical element manufacturing, and the method comprises the steps: calculating an assembly standard deviation based on the historical production data of the double-side cylindrical surface array convex lens; based on a normal distribution model, calculating a preset eccentricity according to a preset qualified tolerance zone and the assembly standard deviation; preparing an upper lens plate and a lower lens plate in batches based on the preset eccentricity; and sequentially folding and bonding the upper lens plate and the lower lens plate to prepare the double-side cylindrical array convex lens in batches. According to the method, random errors which cannot be eliminated are converted into controllable systematic errors, so that the effective yield is greatly improved.

The application relates to a multi-beam forming method and device based on a digital multi-channel cylindrical array, which comprises the following steps: acquiring the azimuth angle, frequency and transceiving mode of a desired beam; calculating the channel number closest to the azimuth angle of the desired beam according to a channel division and numbering rule of the cylindrical array; dynamically dividing a plurality of beam subarrays so that the desired beam is directed to the center of the subarray; mapping the dynamic subarray of the plurality of beams to a corresponding channel enabling table; performing amplitude weighting on the subarray, mapping the amplitude weighting value of the subarray to the corresponding channel of the dynamic subarray, and combining the channel enabling table to obtain an amplitude weighting table of the full array of each beam; calculating the weight coefficient of each channel according to the amplitude weighting table, the amplitude phase compensation value and the frequency; and realizing the above steps through a Vitis HLS tool to generate an IP core and performing digital multi-beam forming in an FPGA. The application guarantees good beam forming performance and can simultaneously form a plurality of transmitting beams or receiving beams in all directions.

The invention discloses a ship radiation noise measurement system and a double-layer cylindrical array measurement device, and the device comprises a circular bottom supporting plate, a circular top supporting plate, a supporting tube, a group of hydrophone vibrators, a distance measurement transducer, a supporting pedestal, and an electronic cabin. The two opposite ends of the supporting pipe are installed in the middle of the bottom supporting plate and the middle of the top supporting plate respectively, the two opposite ends of the hydrophone vibrator are installed on the periphery of the bottom supporting plate and the periphery of the top supporting plate respectively, and the distance measuring transducer is installed on the top supporting plate. The support base is installed below the bottom support plate, the electronic cabin is installed below the bottom support plate, the electronic cabin is surrounded by the support base, and the hydrophone vibrators are respectively connected to the electronic cabin.

The invention discloses a silicon-based partitioned micro-nano composite enhanced boiling heat exchange structure and a preparation method thereof, and belongs to the technical field of enhanced phase change. Comprising a heat dissipation substrate, the upper surface of the heat dissipation substrate comprises a plurality of micro-cylinder array areas with nanowires arranged at the top ends, and the rest areas are smooth micro-cylinder arrays. The smooth micro-cylinder array area can provide channels for liquid supplementation through the channels between the single micro-cylinders, and the micro-cylinder array with the nanowires arranged at the top end can effectively promote generation and separation of bubbles in the boiling heat exchange process. A certain distance is reserved between the micro-cylinder array areas with the nanowires arranged at the top ends, the growth process of bubbles on the boiling surface can be effectively adjusted, excessive fusion of the bubbles in the transverse direction is avoided, and formation of an air film is delayed. Through the unique region division design, a bubble separation path and a liquid supplementing channel can be effectively separated, the local dry-out phenomenon is delayed, and the boiling heat exchange performance is remarkably improved.

The invention discloses a sound tweezer method and circuit control system for megakaryocyte sorting, and the method comprises the following steps: step 1, providing a cell sorting chip which comprises a PDMS flow channel, a two-way sorting flow channel and a three-way sorting flow channel, and the PDMS flow channel is internally provided with a cylindrical array; step 2, injecting a sample solution containing cells or particles with different diameters into the PDMS flow channel; 3, after the cells or the particles are subjected to cylindrical array sorting in the PDMS flow channel, the cells or the particles with the diameters smaller than the critical diameter are guided into a two-separation flow channel from the PDMS flow channel, and the cells or the particles with the diameters larger than the critical diameter are guided into a three-separation flow channel from the PDMS flow channel; and 4, sound fields are applied to the two-way sorting flow channel and the three-way sorting flow channel, and the cells or particles with different diameters enter different outlets respectively by adjusting sound field parameters, so that multi-scale sorting is realized. The multi-scale megakaryocyte sorting device can realize multi-scale megakaryocyte sorting, and has the advantages of high efficiency, stability and convenience in operation.

The present invention discloses a broadband beam-scanning conformal array antenna based on a low-profile frequency selective surface. The antenna comprises a dipole feed, a semi-cylindrical bandpass array antenna, and a semi-cylindrical band-rejection array antenna. The semi-cylindrical bandpass array antenna and the semi-cylindrical band-rejection array antenna are connected to form a hollow three-dimensional cylindrical array antenna. The dipole feed is located at the axis of the three-dimensional cylindrical array antenna. The semi-cylindrical bandpass array antenna is used to transmit electromagnetic waves; the semi-cylindrical band-rejection array antenna is used to reflect electromagnetic waves. By mechanically rotating the three-dimensional cylindrical array antenna, the spatial positions of the semi-cylindrical bandpass array antenna and the semi-cylindrical band-rejection array antenna in the three-dimensional cylindrical array antenna are changed to obtain different beam directions, thereby achieving 360-degree beam scanning in the horizontal plane. The array antenna has the advantages of simple structure, low cost, low loss, and good broadband performance.

The application discloses a convex cylindrical array ultra-precision single-point diamond finishing machining method and relates to the technical field of convex cylindrical array machining, and specifically comprises the following steps: S100, a single-crystal diamond cutter is installed on a single-point diamond ultra-precision lathe, and one workpiece unit of the convex cylindrical array is cut, wherein the single-crystal diamond cutter comprises a cutter handle and a diamond blade, and the diamond blade is in a rectangular or trapezoidal shape; the application adopts the trapezoidal or rectangular cutter which belongs to a straight-line blade cutter, so that the manufacturing cost of the cutter is lower; secondly, the single-crystal diamond cutter in the rectangular or trapezoidal shape moves along the X-axis direction and the Z-axis direction in the unit horizontal plane and rotates around the B-axis, the invalid area at the root of the convex cylindrical array can be effectively removed, the tool path interval during cutting can be larger by adopting the single-crystal diamond cutter with a straight-line blade, the cutting time is effectively shortened, the machining efficiency is improved, and the machining cost is reduced.

This invention provides a full-space staring digital array radar system. The system includes a digital antenna array, a radio frequency front-end, a beamforming network, and a control and processing center. The digital antenna array adopts a structure combining hemispherical and cylindrical surfaces, and the height of the cylindrical array and the radius of the hemispherical array must satisfy a certain relationship. During transmission, the radar controls the beamforming network and corresponding antenna elements of each subarray to transmit signals through the control and processing center. During reception, the radar echo is received by the receiving elements of the digital antenna array to form multiple echo signals, which are then processed by the control and processing center for target detection and tracking. The full-space staring digital array radar system of this invention has superior multi-target and full-space simultaneous surveillance capabilities, improving the radar's early warning efficiency across the entire airspace. It can simultaneously track multiple targets from various airspace angles, providing strong real-time full-space surveillance capabilities.

The invention discloses a preparation method of a conical silicon-based hollow microneedle array, which comprises the following steps of: spin-coating photoresist on the front surface of a monocrystalline silicon wafer, and forming a round hole array pattern on the photoresist after photoetching; performing deep silicon etching on the front surface of the monocrystalline silicon wafer by taking the photoresist of the circular hole array pattern as a mask, and forming a pinhole channel array on the front surface of the monocrystalline silicon wafer; spin-coating photoresist on the back surface of the monocrystalline silicon wafer, forming a cylindrical array pattern on the photoresist after alignment photoetching of the back surface, and wrapping the pinhole channel array in the cylindrical array pattern after the cylindrical array pattern extends along the monocrystalline silicon wafer; performing deep silicon etching on the back surface of the monocrystalline silicon wafer by taking the photoresist of the cylindrical array pattern and the aluminum film as masks, and forming a cylindrical array on the back surface of the monocrystalline silicon wafer; isotropic wet etching is carried out on the cylindrical array formed on the back face of the monocrystalline silicon piece, a conical microneedle array is formed on the back face of the monocrystalline silicon piece, and the conical silicon-based hollow microneedle array is obtained. The conical silicon-based hollow microneedle array has the advantages of high depth-to-width ratio, controllable hollow channel diameter and smooth surface.

The application discloses a kind of based on asymmetric hollow cylindrical metasurface terahertz biosensor and method thereof.The sensor is obtained by periodic arrangement by metasurface unit;Each metasurface unit is composed of dielectric substrate and hollow cylindrical array unit.The application introduces asymmetric disturbance by asymmetric arrangement of four hollow cylindrical array units of hollow cylindrical body, and induces terahertz wave to form quasi-continuous body bound state (Q-BIC) resonance peak with super-high Q value on it, realizes Q value up to 20000 or more using quasi-continuous domain bound state induction mechanism, can produce obvious response signal in terahertz spectrum, so as to realize the super-sensitive detection of trace biological substance, greatly improve detection efficiency and accuracy.

Ultrasonic excitation to a sample is provided with an apparatus including: a cylindrical ultrasonic transducer, and a plate disposed on an end of the cylindrical ultrasonic transducer. The ultrasonic transducer is configured to provide a vertical vibration in operation. A Lamb wave vibration is generated in the plate by the vertical vibration of the ultrasonic transducer. The Lamb wave vibration converges at a central region of the plate, where a sample is disposed. Alternatively, a cylindrical array of ultrasonic transducers can be used instead of a single cylindrical transducer. Such an array can be driven as a phased array for beam shaping and / or multi-focusing.

The application discloses a porous medium resistance coefficient calculation method, system, computer equipment and medium. The method adopts a cylindrical array to construct a porous medium geometric model, determines a flow calculation domain of the porous medium geometric model, and performs structural grid division on the flow calculation domain. A high-resolution numerical method is adopted to carry out computational fluid dynamics simulation on the porous medium geometric model, so that a flow characteristic database of the porous medium geometric model is obtained. The flow characteristic database is subjected to integral statistics, so that a resistance coefficient dataset of the porous medium geometric model is obtained. The resistance coefficient equation of the porous medium geometric model is constructed according to the resistance coefficient dataset. The porous medium resistance coefficient calculation method provided by the application does not need complex modeling, has wide application range, can capture more fine flow details, solves more complex flow problems, is simple and efficient in calculation, and is more accurate in calculation result.