70 results about "Permittivity distribution" patented technology

A method for determining the flow rates of a fluid comprising a multi-component mixture of a gas and at least one liquid in a pipe, the method comprising the following steps: a) the multi-component mixture flow is conditioned to create a symmetrical annular gas concentration flow condition, b) the density distribution and / or dielectric constant distribution in said symmetrical flow within a cross-section of the pipe is determined, c) a function describing the radial distribution of density and / or radial distribution of dielectric constant is determined, d) the velocity of the multi-component mixture is determined, e) the temperature and pressure are obtained, and, f) based on the knowledge of densities and / or dielectric constants of the components of the fluid mixture, and the result from the above steps a-e, the volume and / or mass flow rates of the gas and liquid components of the fluid mixture are calculated. An apparatus for performing the method is also disclosed.

The problem to be solved by the invention is to restrain local heating peculiar to microwave heating to thereby realize the uniform heating of an object to be heated and thus enhance the condition of the object to be heated after heated. In a microwave heating method for supplying microwaves into a heating chamber 11 storing therein an object to be heated to heat the object to be heated, microwaves are supplied into the heating chamber 11 to heat the object to be heated; the temperature of the object to be heated is measured to check whether a given temperature difference has been generated in the temperature distribution of the object to be heated; and, when the given temperature difference has been generated, the minute particles of water are supplied into the heating chamber 11 to change the permittivity distribution state within the heating chamber 11, thereby changing the distribution of electric fields caused by the microwaves supplied into the heating chamber 11.

The invention relates to a low-profile lens antenna capable of realizing wide-angle scanning. The lens antenna comprises a lens and a feed source positioned on the focal plane of the lens; beam scanning and tracking can be realized by mechanical control on the feed source; the lens has an electromagnetic wave focusing function, and the appearance of the lens can be flat-plate-shaped or curved-surface-shaped, and conformal design with a carrier platform can be realized; the effective dielectric constant distribution characteristic of the lens is that the effective dielectric constants are decreased from the center to the edges along the horizontal and longitudinal directions; the regulation and control on the effective dielectric constants can be realized by changing the structure or dimensions of the metamaterial units; and the assembling and preparation of the lens at a low cost is realized by multiple metamaterial panels in a stacked manner. The low-profile lens antenna has the characteristics of broadband, high gain, low profile, easy conformal property and the like, and is particularly suitable for high-gain conformal vehicle-mounted or missile-borne platforms in the fields of communication measurement and control, and the like.

The present invention provides a system and method for multi-phase flow decomposition using electrical capacitance imaging techniques. The present invention provides a system and method to obtain permittivity distributions at a plurality of frequency markers using volume tomography image reconstruction to determine volume fraction of each phase and to produce images of the volume fraction for each phase.

The present invention relates to a method and a system for determining a set of process parameters of a treatment unit in which unit a product is subjected to a temperature treatment, the method comprising: subjecting a product to an electromagnetic signal before, during and / or after a temperature treatment, wherein said electromagnetic signal is adapted to interact with said product dependent upon the dielectric constant distribution of said product, receiving an electromagnetic signal which has interacted with said product, analysing the received electromagnetic signal in comparison with the transmitted electromagnetic signal and thereby determining a response being dependent upon the dielectric constant distribution of said product and based thereupon determine the temperature (distribution) or water content of the product, and analysing said temperature distribution or temperature of the product or products and based thereupon determining a set of process parameters for a temperature treatment in a treatment unit.

The invention discloses an electromagnetic inverse scattering imaging method based on compressed sensing and relates to a microwave imaging technology. The electromagnetic inverse scattering imaging method comprises the following steps of: step 1, microwave excitation and measurement stage, carrying out penetrating irradiation on a target by microwave outside the target and measuring a scattering back wave of the target so as to sense internal structure and material of the target; step 2, target molding stage, establishing a nonlinear observation model between dielectric constants and the scattering back wave of the target and establishing a representation model describing sparsity of the internal structure of the target; and step 3, calculating imaging stage, imaging distribution of the dielectric constants of the target by using a target model and a compressed sensing processing method, wherein imaging results are used as representations of the internal structure of the target as different dielectric constants correspond to different constituent materials of the target. Compared with the conventional microwave imaging method, the compressed sensing processing technology is utilized by the electromagnetic inverse scattering imaging method so that the back wave observation data amount is significantly reduced and the imaging definition of the internal structure of the target is significantly improved simultaneously.

The invention provides a method for calculating the radar scattering properties of a stable section of aircraft wake flow in clear sky. According to the technical scheme, the method includes the steps of firstly, calculating dielectric constant distribution and internal electric field distribution of the aircraft wake flow, and then calculating the high vibration integration derived from a scattering integral equation to obtain the radar scattering cross section of the aircraft wake flow. Compared with a conventional method for calculating the electromagnetic scattering properties, the method has the advantages that the calculated amount and the storage amount are lowered in a magnitude mode, the relationship between the radar scattering cross section of the aircraft wake flow and the frequency of incident waves can be calculated and obtained through the method, and theory supports and model supports are provided for the development of the related radar detection technologies.

The invention discloses a dielectric constant distribution optimization method of a functional gradient insulator for a GIS (Geographic Information System), which takes a supporting insulator for theGIS as an optimization model and takes a direction (z axis) from a high-voltage electrode of the insulator to a ground electrode as a direction (z axis) to carry out gradient distribution optimizationcalculation on a dielectric constant. For the purpose of surface electric field distribution homogenization of the insulator, the optimal gradient distribution of the dielectric constant of the insulator is obtained by adopting an iterative calculation method. Wherein the iteration variable of the iteration calculation is an adjustment coefficient k (z) and a dielectric constant r (z) of the insulator; wherein the iteration ending criterion is that the non-uniformity coefficient f of the surface electric field distribution of the insulator is smaller than a preset electric field non-uniformity coefficient f0. The method has important theoretical value and engineering significance for improving the operation stability of the GIS and the safety of the power system.

There is provided a structure for supporting propagation of surface plasmon polaritons. The structure includes a plasmonic material region and a dielectric material region, disposed adjacent to a selected surface of the plasmonic material region. At least one of the plasmonic material region and the dielectric material region have a dielectric permittivity distribution that is specified as a function of depth through the corresponding material region. This dielectric permittivity distribution is selected to impose prespecified group velocities, vgj, on a dispersion relation for a surface polaritonic mode of the structure for at least one of a corresponding set of prespecified frequencies, ωj, and corresponding set of prespecified wavevectors, kj, where j=1 to N.

The invention discloses an electromagnetic imaging system and method employing an oblique incident wave. A scatterer is fixed on a rotating platform, and the periphery of the scatterer is uniformly provided with a plurality of receiving antennas at intervals. All receiving antennas are connected to a microwave switching network, and the needed receiving antennas are selected to be connected for operation through the microwave switching network. The microwave switching network is connected with a vector network analyzer, and the vector network analyzer is connected with a transmitting antenna through a radio frequency power amplifier. The incident field data and the total field data after each rotation are obtained firstly, and then the subtraction of the incident field data and the total field data is carried out to obtain the scattering field data of each measurement. An imaging region is equally divided to obtain a Green function, and a target function is built. An optimization algorithm is employed for solving the minimum value of the target function, and the distribution of dielectric constants is obtained. The system and method solve a problem of shading and cross coupling of receiving and transmitting antennas in an electromagnetic imaging system employing normal incident waves. The receiving and transmitting antennas can be flexibly arranged, and the proper incident angles can be freely selected according to the actual conditions.

The invention relates to a defect detection and positioning method of planar array electrical capacitance tomography based on partial fractal dimensions. The defect detection and positioning method comprises the following steps: S1, putting a sample to be detected on a planar electrode array sensor in parallel in an alignment manner and measuring a capacitance value at the moment; taking the capacitance value as a capacitance value of a measurement object field; S2, reconstructing an image: reconstructing a dielectric constant distribution image by utilizing an LBP (Local Binary Pattern) algorithm; S3, processing the image: extracting a color matrix corresponding to a defect color in a false-color image; S4, partitioning the reconstructed image into blocks and calculating a fractal dimension of each block; determining a threshold value according to a fractal dimension histogram of the blocks of the reconstructed image; S5, marking a square hole with the fractal dimension which is greater than the threshold value to obtain a final marking result. The invention provides an electrical capacitance tomography detection method based on a planar array electrode, aiming at defects of a sticking layer of a composite material structure for aviation; a fractal theory is applied to defect automatic positioning of the reconstructed image of the electrical capacitance tomography of the planar array electrode, so that the defects of the reconstructed image are automatically marked and the defect positioning precision is improved.

The invention provides a dielectric lens. The dielectric lens is a lenticular lens or ellipsoidal lens with a quasi-elliptical cross-sectional profile. The dielectric lens formed by piling up a numberof unit bodies. Through the permittivity distribution of the unit bodies in the dielectric lens, a quasi-elliptical non-plane wave in the minor axis direction becomes a plane wave through the dielectric lens. The unit bodies of the dielectric lens are prepared by extrusion, injection molding, stamping, CNC machining or a 3D printing technology. The assembly of the unit bodies can be glue joint, welding, structure clamp connection or direct 3D printing. When the dielectric lens is applied to a cleave antenna, the system capacity of a communication system can be improved. Compared with a traditional cylindrical luneberg lens antenna, the cleave antenna has reduced lens thickness.

The invention provides a measurement method of liquid level and position of a tank body. Distribution situation of liquid in the tank body is calculated according to distribution situation of dielectric constant distributed in every section of the measurement structure, and thereby relevant information such as average density and phase content of the liquid in the tank body can be calculated. The measurement method of the liquid level and the position of the tank body has the advantages of being simple in structure and design, different from the traditional capacitance measurement method, and capable of greatly reducing influences of distribution parameters and other effects on measurement, and improving measurement accuracy of the system due to the fact that sectional type time-sharing measurement is adopted.

The invention discloses a carbon fiber-reinforced composite material electrical loss heating temperature field active control method. The method comprises putting a lot of ordered and mutually insulated array electrodes on edges of all layers of a composite material, independently electrifying the pairs of the electrodes to carry out electrical loss heating, and actively controlling an integral temperature field of the composite material through the monitored material interlayer and in-plane temperature field distribution as a feedback signal and superposition or compensation of uneven heatingstates in the action zones of the pairs of the electrodes. The method solves the problem that the heating temperature field is uneven because of the non-uniform distribution of volume resistivity anddielectric constant of the composite material in the electrical loss heating process, and realizes high-quality integrated electrical loss heat curing of the carbon fiber composite component.

The invention relates to a capacitive tomography image reconstruction method based on a closed-loop control principle. The method mainly comprises the following steps of firstly, obtaining N(N-1) / 2 independent measurement values under an empty field condition and N(N-1) / 2 independent measurement values under the condition that an object exists through measurement by utilizing a capacitive tomography imaging system, and establishing an N*N capacitive variation matrix by utilizing a difference between the two types of the independent measurement values; secondly, taking a Calderon algorithm as acontrolled object, solving a new capacitive variation matrix by utilizing dielectric constant distribution inversely derived by the algorithm to serve as a negative feedback, and correcting a deviation value of capacitive variation by adjusting parameters of a PID controller, thereby enabling a whole closed-loop to be converged; and finally, if the number of iterations reaches a preset number ofiterations, ending the iteration and outputting a reconstruction result, otherwise, continuing the iteration. According to the method, the closed-loop control principle is combined with the Calderon algorithm for the first time, so that an image reconstruction error can be effectively reduced and the image reconstruction quality is remarkably improved; and the method has important practical valuesand good application prospects in the field of electrical imaging.

The present invention relates to a thermosetting resin sandwich prepreg, and the copper clad laminates and multi-layered printed circuit wiring boards manufactured therefrom. The interlayer of the thermosetting resin sandwich prepreg contains the thermosetting resin composition with a high content of fillers, and the outer layer of the prepreg contains the thermosetting resin composition with a low content of fillers. The copper clad laminates prepared by using the prepregs have good adhesion to metal foils, insulativity and uniform dielectric constant distribution.

A method propagates a pulse of wave through the material to receive a set of echoes resulted from scattering the pulse by different portions of the material and simulates a propagation of the pulse in the material using a neural network to determine a simulated set of echoes. Each node in a layer of the neural network corresponds to a portion of the material and assigned a value the permittivity of the portion of the material, such that the values of the nodes at locations of the portions form the image of the distribution of the permittivity of the material. The connection between two layers in the neural network models a scattering event. The method updates the values of the nodes by reducing an error between the received set of echoes and the simulated set of echoes to produce an image of the distribution of the permittivity of the material.

The invention relates to an optical conversion multi-beam conformal lens antenna. The optical conversion multi-beam conformal lens antenna comprises four parts comprising a dielectric lens, a multi-beam Rotman lens, a cylindrical conformal microstrip antenna array and a conformal floor, wherein the dielectric lens covers the cylindrical conformal microstrip antenna array, the conformal microstripantenna array is placed on the conformal floor, and the multi-beam Rotman lens is used for feeding the cylindrical conformal microstrip antenna array. By covering the cylindrical conformal array withthe quasi-conformal optical conversion dielectric lens, the cylindrical conformal array is equivalent to a virtual space planar array, and the converted non-uniform dielectric constant distribution isachieved by a dielectric punching periodic structure; the multi-beam Rotman lens is a multi-beam feeding network of the antenna and comprises a dielectric substrate, a copper laying plane, an input port, an output port, a virtual port, a copper laying lens cavity and a transmission line, the copper laying plane is formed on a lower surface of the substrate, the copper laying lens cavity is formedin an upper surface of the substrate, and the transmission line is connected with the lens and the conformal array; and by the optical conversion multi-beam conformal lens, seven beams within a coverage range being (-45)-(+45) degrees can be formed.

The invention relates to a microwave-imaging-fused electrical capacitance tomography method including acquisition of electrical capacitance data and microwave imaging data measured in a to-be-imaged area; acquisition of dielectric constant distribution of a measured material in the to-be-imaged area according to image reconstruction iterative algorithm and the electrical capacitance data, wherein the dielectric constant distribution of microwave imaging data conversion in the iterative algorithm can be used as an initial iteration value. Iteration times can be reduced by the iterative algorithm, and imaging speed is improved, so that the iterative algorithm can be actually applied in circulating fluidized bed, coating and other processes, a more accurate gas solid concentration distribution image can be obtained, and the process can be more effectively monitored.

The invention relates to a novel metamaterial which comprises at least one material plate layer. Each material plate layer comprises a substrate and artificial microstructures attached onto the substrate. The substrate is virtually divided into a plurality of substrate units arranged in array mode. A pair of artificial microstructures is attached onto each substrate unit. Each pair of artificial microstructures comprises a first artificial microstructure and a second artificial microstructure attached onto each substrate unit. The first artificial microstructures and the second artificial microstructures are of snowflake-shaped structures or of derived structures of the snowflake-shaped structures. Each snowflake-shaped structure comprises two I-shaped structures orthogonal with each other. Each I-shaped structure comprises a first metal line, a second metal line and a third metal line connecting the first metal line and the second metal line, wherein the first metal line and the second metal line are parallel to each other. The third metal lines of the two I-shaped structures intersect and are perpendicular to each other. The material has broadband high dielectric constant in a certain frequency band, has distribution of dielectric constants gradually increasing from zero in another frequency band and can meet requirements of a specific situation.

The invention discloses a method and a system for detecting polymer lithium battery pack consistency. The system comprises a capacitance sensor, a data collector and an image imager. The capacitance value between capacitance sensor electrodes of the to-be-detected polymer lithium battery pack is measured, a capacitance tomography image reconstruction algorithm is adopted to reconstruct the capacitance value to a polymer lithium battery pack inner dielectric constant distribution, a standard relation curve for the polymer lithium battery pack inner dielectric constant distribution and the consistency is built, the standard relation curve is compared with the to-be-detected polymer lithium battery pack inner dielectric constant distribution, and the consistency of the to-be-detected polymer lithium battery pack is obtained. The method and the system have the advantages of non intrusion, quick response speed and convenient operation and the like.

The invention discloses an improved defective ground structure low-pass filter. The invention adopts a special two-step impedance structural unit, which adopts a structural mode of narrow rectangularconnection hexagonal structural unit, can shorten the length of the step impedance structural unit without reducing the load Q, has great degree of freedom in structure and design, and is easy to realize miniaturization of microwave device. In addition, the invention optimizes the defect ground structure of the bottom and changes the effective dielectric constant distribution of the substrate material, thereby affecting the current distribution of the ground plane and the transmission characteristics of the microstrip transmission line. Such a defective structure of the invention improves thelow-pass filtering characteristics of the low-pass filter by increasing the high impedance frequency width and the out-of-band rejection strength of the low-pass filter. Moreover, this kind of defectground structure, the structure is relatively simple, easy to electromagnetic field theory analysis and equivalent circuit modeling analysis, more suitable for the practical application of integratedcircuits advantages.

The invention discloses a high polymer bonding explosive density distribution detection method based on capacitive tomography. A capacitance value between parallel plates is measured through a parallel plate capacitance method, relative dielectric constants of PBX materials under different densities are obtained through calculation, and a PBX material density value and a dielectric constant modelare established; a capacitance tomography system is built, the capacitance value between array electrode pairs of a to-be-tested PBX test piece array are measured in sequence, and three-dimensional reconstruction is carried out on the relative dielectric constant distribution of the PBX materials according to the measured capacitance value and the sensitivity matrix between all the electrode pairs; and according to the relative dielectric constant of the PBX material-PBX material density model, the density distribution of the PBX test piece is obtained, and detection of the density distribution of the PBX test piece is realized. According to the method, the density distribution of the PBX test piece can be quantitatively detected, and the method has the advantages of no damage, high efficiency and large detection range / portability, and can be widely applied to detection of density distribution determination and density uniformity of PBX test pieces.

The invention relates to a novel metamaterial which comprises at least one material plate layer. Each material plate layer comprises a substrate and artificial microstructures attached onto the substrate. The substrate is virtually divided into a plurality of substrate units arranged in array mode. A pair of artificial microstructures is attached onto each substrate unit. First artificial microstructures are of snowflake-shaped structures. Each second artificial microstructure comprises a first open ring structure, a second open ring structure and an I-shaped structure. Each I-shaped structure comprises a first metal line, a second metal line and a third metal line, wherein the first metal line and the second metal line are parallel to each other, and two ends of the third line are connected with the first metal line and the second metal line respectively. The third metal lines penetrate through the first open ring structures and the second open ring structures. The material has broadband high dielectric constant in a certain frequency band, has distribution of dielectric constants gradually increasing from zero in another frequency band and can meet requirements of a specific situation.

The invention provides a preparation method of a metamaterial medium substrate; by adding organic solutions with different mass fractions into different areas of a porous material substrate and by the high temperature crosslinking of the organic solutions, a molded metamaterial medium substrate contains organic polymers with different masses at different areas; thereby the metamaterial medium substrate has heterogeneous dielectric constant distribution, which provides the metamaterial medium substrate with a specific electromagnetic modulation function; and the function application of the metamaterial is expanded.