Internal structure estimation device, internal structure estimation method, and program

Abstract

To provide an internal structure estimation device, an internal structure estimation method and a program which can estimate the distribution dielectric constant of the interior of a measurement object.SOLUTION: An internal structure estimation device comprises: a measurement result acquisition unit which acquires a measurement result including at least the electrostatic capacitance of a target object; a supply unit which gives a measurement result to a learned model that has learned a correspondence between an analysis result of the distribution of the dielectric constant of the object analyzed using an analysis model including an internal structure of the object and information about the internal structure of the object; and an output unit which estimates the internal structure of the target object on the basis of the learned model given with the measurement result and outputs the estimated estimation result.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an internal structure estimation device, an internal structure estimation method, and a program.

Background Art

[0002] A method for estimating the dielectric constant of an object has been proposed. For example, in the technique described in Patent Document 1, the similarity between the received measurement data and the calculated data obtained by assuming the dielectric constant of the object in the same positional relationship between the transmitting unit and the receiving unit as when the measurement data was obtained is calculated. The transmitting unit transmits radio waves toward the inside of an object having a three-dimensional shape, the receiving unit is arranged at a position sandwiching the object between the transmitting unit, and the receiving unit receives the radio waves that have passed through the object.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the technique described in Patent Document 1 only estimates the real part of the dielectric constant of a uniform substance. For example, inside a living body or a concrete column in which foreign substances are mixed, substances having a plurality of dielectric constants are mixed, and in many cases, the shapes and dielectric constants of the plurality of substances are unknown. Therefore, the technique described in Patent Document 1 cannot handle such objects. Furthermore, the technique described in Patent Document 1 cannot handle functional materials in which the dielectric constant changes depending on the location. Conventionally, the dielectric constant has often been measured for a uniform substance, and when a plurality of substances are present, it has been difficult to estimate the positions and dielectric constants of the substances non-destructively.

[0005] The present invention has been made in view of the above-mentioned problems, and aims to provide an internal structure estimation device, an internal structure estimation method, and a program that can estimate the distributed dielectric constant inside an object to be measured. [Means for solving the problem]

[0006] To achieve the above objective, an internal structure estimation device according to one aspect of the present invention includes: a measurement result acquisition unit that acquires measurement results including at least the capacitance of a target object; a supply unit that provides the measurement results to a trained model in which the correspondence between the analysis results of the dielectric constant distribution of the object, which has been analyzed using an analysis model including the internal structure of the object, and information regarding the internal structure of the object has been learned; and an output unit that estimates the internal structure of the target object based on the trained model to which the measurement results have been provided, and outputs the estimated result.

[0007] Furthermore, in an internal structure estimation device according to one aspect of the present invention, the analysis results may be obtained by analyzing the analysis model using the finite element method.

[0008] Furthermore, in an internal structure estimation device according to one aspect of the present invention, the analysis results may be such that they show the relationship between the rotation angle from a reference position when the object is rotated around a rotation axis in the analysis model, when measuring electrodes are placed at predetermined positions, and the capacitance measurement results by the measuring electrodes for each rotation angle.

[0009] Furthermore, in an internal structure estimation device according to one aspect of the present invention, the measuring electrode includes a high-potential electrode and a plurality of low-potential electrodes having different areas and lower potential than the high-potential electrode, the rotation axis is arranged in a space where the high-potential electrode and the plurality of low-potential electrodes face each other, and the analysis result may be obtained by rotating the object arranged in the space around the rotation axis in the analysis model.

[0010] Furthermore, in an internal structure estimation device according to one aspect of the present invention, the analysis result may include at least one of the potential between the high-potential electrode and the low-potential electrode, and the loss between the high-potential electrode and the low-potential electrode.

[0011] Furthermore, in an internal structure estimation device according to one aspect of the present invention, the measurement result may be such that the measuring electrode placed at a predetermined position includes a high-potential electrode and a plurality of low-potential electrodes having different areas and lower potential than the high-potential electrode, and the axis of rotation for rotating the target object is the capacitance measured by a measuring device placed in a space where the high-potential electrode and the plurality of low-potential electrodes face each other.

[0012] To achieve the above objective, an internal structure estimation method according to one aspect of the present invention includes: a measurement result acquisition unit that acquires measurement results of a target object; a supply unit that provides the measurement results to a trained model in which the correspondence between the analysis results of the distributed dielectric constant of the object, which has been analyzed using an analysis model including the internal structure of the object, and information about the object has been learned; and an output unit that estimates the internal structure of the target object based on the trained model to which the measurement results have been provided, and outputs the estimated result.

[0013] To achieve the above objective, a program according to one aspect of the present invention causes a computer to acquire measurement results of a target object, to provide the measurement results to a trained model that has learned the correspondence between the analysis results of the distributed dielectric constant of the object, which has been analyzed using an analysis model that includes the internal structure of the object, and information about the object, to estimate the internal structure of the target object based on the trained model to which the measurement results have been provided, and to output the estimated result. [Effects of the Invention]

[0014] According to one aspect of the present invention, the distributed dielectric constant inside the object being measured can be estimated. [Brief explanation of the drawing]

[0015] [Figure 1]It is a diagram showing a configuration example of an internal structure estimation device according to an embodiment. [Figure 2] It is a diagram showing an example of an analysis model according to an embodiment. [Figure 3] It is a diagram for explaining an example of an analysis model for potential analysis according to an embodiment. [Figure 4] It is a diagram showing a configuration example of a measurement device according to an embodiment. [Figure 5] It is an equivalent circuit diagram of an analysis model and a measurement device according to an embodiment. [Figure 6] It is a diagram showing a configuration example of a potential measurement device according to an embodiment. [Figure 7] It is a diagram for explaining the learning of a model according to an embodiment.. <> [Figure 8] It is a diagram for explaining an estimation method using a model according to an embodiment. [Figure 9] It is a diagram showing a first example of data learned by a model according to an embodiment. <> <> [Figure 10] It is a diagram showing an example object of the second example. <> <> [Figure 11] It is a diagram showing a second example of data learned by a model according to an embodiment. <> <> [Figure 12] It is a diagram showing an example of an analysis result of potential. <> <> [Figure 13] In potential analysis, it is a diagram for explaining the rotation angle of an analysis target. <> <> [Figure 14] It is a diagram showing an example of an analysis result of potential for each dielectric constant when the rotation angle of an object is around 180 degrees. <> <> [Figure 15] It is a diagram for explaining an analysis model when an object is composed of a plurality of dielectrics. <> <> [Figure 16] It is a diagram showing an analysis result of the image g350 in FIG. 15. <> <> [Figure 17] It is a diagram showing an analysis result of the image g360 in FIG. 15. <> <> [Figure 18] It is a flowchart of a processing procedure of an internal structure estimation device according to an embodiment. <> <> [Figure 19] It is a flowchart of a processing procedure during actual measurement according to an embodiment. <> [Modes for carrying out the invention]

[0016] Embodiments of the present invention will be described below with reference to the drawings. Note that in the drawings used in the following description, the scale of each component has been appropriately changed to ensure that each component is recognizable.

[0017] [Example of an internal structure estimation device configuration] Figure 1 shows an example of the configuration of the internal structure estimation device according to this embodiment. As shown in Figure 1, the internal structure estimation device 1 comprises a condition acquisition unit 11, a calculation unit 12, a learning unit 14, a model storage unit 15, an acquisition unit 17 (measurement result acquisition unit), a supply unit 18, and an output unit 19. The calculation unit 12 comprises, for example, an analysis model 13. The model storage unit 15 comprises a model 16.

[0018] The internal structure estimation device 1 acquires measurement results of an object whose internal structure is unknown and estimates information about the object's internal structure (hereinafter, "information about the internal structure" is also referred to as "internal structure information") using a trained model 16. The measurement results are at least capacitance and may include potential and loss. The internal structure information is, for example, the distribution of relative permittivity (distributed permittivity) inside the object. The internal structure information may also include, for example, the internal structure of the object, the shape of the object, the size of the object, and, if the object is composed of multiple dielectrics, the arrangement of the dielectrics.

[0019] The measuring device 2 measures the capacitance, loss, and potential of the target object during estimation. The configuration of the measuring device 2 and the measurement method using the measuring device 2 will be described later. The measuring device 2 also includes a potential measuring device 21.

[0020] The condition acquisition unit 11 acquires information about the internal structure of an object when training the model 16.

[0021] During learning, the calculation unit 12 analyzes the acquired internal structure information, the analysis model 13, and, for example, the finite element method, considering the real and imaginary parts of the dielectric constant, to calculate the analysis results of the object that are assumed to be measured by the measuring device 2 when the object is rotated. The analysis results include, for example, the capacitance and loss for each rotation angle, and the potential at each position on the circumference.

[0022] The learning unit 14 performs model 16 training by associating the internal structure information acquired by the condition acquisition unit 11 with the analysis results calculated by the calculation unit 12 and supplying them to the model 16. Examples of objects to be trained will be described later, but examples of objects to be trained include objects with different shapes, objects with different sizes, objects with structures that have different relative permittivity within a single object, and objects consisting of multiple structures. Furthermore, the data used for training may be the results calculated by simulation, or it may be the measured results measured by the measuring device 2.

[0023] Model 16 is trained by the learning unit 14.

[0024] During estimation, the acquisition unit 17 acquires the measurement results obtained by the measuring device 2 when measuring the target object to be estimated. The acquisition unit 17 outputs the acquired measurement results to the supply unit 18.

[0025] The supply unit 18 supplies the measurement results to the trained model 16 during estimation.

[0026] The output unit 19 outputs parameters, which are estimated results for the target object output by the trained model 16 given the measurement results, to the external device 3. The external device 3 is, for example, an image display device, a printing device, a tablet terminal, a personal computer, etc. The output unit 19 may also be equipped with a wireless or wired communication circuit.

[0027] [Analysis Model] Next, we will explain analysis model 13. Figure 2 shows an example of an analysis model according to this embodiment. The analysis model 13 includes, for example, a first electrode 102 (high potential electrode), auxiliary electrodes 103 and 104, a second electrode 105 (low potential electrode), a third electrode 106 (low potential electrode), and a fourth electrode 107 (low potential electrode) inside an outer cylinder 101. The analysis model 13 also includes a model of the object to be analyzed, as shown in Figure 2.

[0028] The diameter of the outer cylinder 101 is, for example, 98 mm. The length of one side of the second electrode 105 is, for example, 20 mm. The length of one side of the third electrode 106 is, for example, 18 mm. The length of one side of the fourth electrode 107 is, for example, 16 mm. The first electrode 102, auxiliary electrode 103, auxiliary electrode 104, second electrode 105, third electrode 106, and fourth electrode 107 are arranged on the same circumference. The center of the circumference of these electrodes is the center point P, which is the axis of rotation that rotates the object 5.

[0029] The outer cylinder 101 is for shielding and has a voltage of 0 (V). The first electrode 102 is the high-potential electrode and has an applied voltage of, for example, 2 (V). The second electrodes 105 to the fourth electrodes 107 are the low-potential electrodes and have a voltage of, for example, 0 (V). The auxiliary electrodes 103 and 104 have a voltage of, for example, 0 (V).

[0030] In the simulation, the object 5, whose internal information is estimated, is placed at a distance d from the center point P to the center of the object 5 and inside the electrodes, as shown in Figure 2, and rotated 360 degrees relative to the center point P. Then, in the simulation, the capacitance, potential, and loss of the second electrode 105, the third electrode 106, and the fourth electrode 107 are calculated for each rotation angle of the object 5.

[0031] The calculation unit 12 calculates the capacitance generated between the electrodes using the following equations (1) and (2).

[0032]

number

[0033]

number

[0034] In equations (1) and (2), Q is the amount of electric charge (C), n is the unit normal vector of the measuring electrode, and S is the area (m²) of the electrode on the lower potential side to which the ammeter is connected. 2 ), D is the electric flux density (C / m) on the electrode plate on the electrode side of the lower potential side. 2 ), where V is the potential difference between the measuring electrodes and is 2(V).

[0035] First, the calculation unit 12 calculates the amount of charge Q on the lower potential side of the measuring electrode using equation (1). To do this, the calculation unit 12 integrates the electric flux density on the measuring electrode with respect to the electrode area to calculate the amount of charge Q. Next, the calculation unit 12 calculates the capacitance using equation (2).

[0036] Note that the analysis model 13 shown in Figure 2 is just one example and is not limited to this. For example, the number of measuring electrodes (electrodes 2 to 4) can be two or four or more. In the following example, we will explain an example where there are three measuring electrodes (electrodes 2 to 4). Also, the size and voltage values ​​of each electrode are just examples and are not limited to these.

[0037] Furthermore, while the example given for the side lengths of the second to fourth electrodes being 20 mm, 18 mm, and 16 mm was explained, this is not the only option. The side lengths could be, for example, 20 mm, 16 mm, and 18 mm, or 18 mm, 20 mm, and 16 mm, etc. In other words, the multiple measuring electrodes can be of different sizes.

[0038] [Example of an analysis model for electrical potential measurement] Next, we will explain an example of an analysis model for potential analysis. Figure 3 is a diagram illustrating an example of an analysis model for potential analysis according to this embodiment. As shown in Figure 3, the calculation unit 12 calculates the potential at each position (g11) indicated by the circles using the finite element method in order to measure the potential at all of these positions. The analysis model 13 also includes this analysis model for potential analysis.

[0039] [Measuring device] Next, we will describe the measuring device 2. Figure 4 shows an example of the configuration of a measuring device according to this embodiment. The measuring device 2 includes, for example, a first electrode 202 (high potential electrode), an auxiliary electrode 203 (not shown), an auxiliary electrode 204 (not shown), a second electrode 205 (low potential electrode), a third electrode 206 (low potential electrode), and a fourth electrode 207 (low potential electrode) inside an outer cylinder 201. The auxiliary electrode 203 is provided next to the second electrode 205, similar to the auxiliary electrode 103, and the auxiliary electrode 204 is provided outside the fourth electrode 207, similar to the auxiliary electrode 104. The measuring device 2 includes a capacitance meter 211 for measuring the capacitance between the first electrode 202 and the second electrode 205, a capacitance meter 212 for measuring the capacitance between the first electrode 202 and the third electrode 206, and a capacitance meter 213 for measuring the capacitance between the first electrode 202 and the fourth electrode 207. The measuring device 2 includes a loss meter 221 for measuring the loss between the first electrode 202 and the second electrode 205, a loss meter 222 for measuring the loss between the first electrode 202 and the third electrode 206, and a loss meter 223 for measuring the loss between the first electrode 202 and the fourth electrode 207.

[0040] Note that the measuring device 2 shown in Figure 4 is just an example, and its shape and configuration are not limited to this. For example, there may be only one capacitance meter and one loss meter. In this case, the measuring device 2 may measure the capacitance and loss between the first electrode 202 and the second electrode 205 on the first rotation of the object, measure the capacitance and loss between the first electrode 202 and the third electrode 206 on the second rotation, and measure the capacitance and loss between the first electrode 202 and the fourth electrode 207 on the third rotation. Also, there may be two or more electrodes from the second to the fourth electrode, as long as the number matches the analysis model 13.

[0041] Figure 5 shows the equivalent circuit diagram of the analysis model and measurement device according to this embodiment. The first electrode 302 (high potential electrode) is connected to one end of the AC power supply 331, one end of the voltmeter 311, one end of the voltmeter 312, and one end of the voltmeter 313. The other end of the AC power supply 331 is connected to the outer casing 301. The auxiliary electrode 303 is connected to the outer cylinder 301. The auxiliary electrode 304 is connected to the outer cylinder 301. The second electrode 305 (low-potential electrode) is connected to the other end of the voltmeter 311 and to one end of the ammeter 321. The third electrode 306 (low-potential electrode) is connected to the other end of the voltmeter 312 and to one end of the ammeter 322. The fourth electrode 307 (low-potential electrode) is connected to the other end of the voltmeter 313 and to one end of the ammeter 323. The other end of ammeter 321, the other end of ammeter 322, and the other end of ammeter 323 are connected to the outer cylinder 301.

[0042] [Electrical potential measuring device] Next, the potential measuring device 21 will be described. Figure 6 shows an example of the configuration of the potential measuring device according to this embodiment. The potential measuring device 21 measures the potential at each position on the circumference using a potentiometer 231, similar to the analysis model shown in Figure 3.

[0043] [Learning Methods] Next, we will explain an example of how to train Model 16. Figure 7 is a diagram illustrating the learning of the model according to this embodiment. As shown in Figure 7, during learning, the learning unit 14 inputs the simulation results (analysis results) or measurement results (measurement results measured when the target object is rotated) and the internal information of the object used in the simulation into the model 16, thereby allowing the model 16 to learn the correspondence. The simulation results include the relationship between the capacitance and rotation angle of each electrode, the relationship between the potential and rotation angle of each electrode, and the relationship between the loss and rotation angle of each electrode, calculated using the analysis model 13. The measurement results include the relationship between the capacitance and rotation angle of each electrode, the relationship between the potential and rotation angle of each electrode, and the relationship between the loss and rotation angle of each electrode. The internal information includes, for example, the internal structure of the object, the distribution of dielectric constants inside the object, the shape of the object, the size of the object, the number of dielectrics in the object, the arrangement of dielectrics in the object, etc. The algorithm used for learning is, for example, a decision tree, a random forest, a support vector machine, a neural network, etc.

[0044] Thus, in this embodiment, the correspondence between internal information of an object and information about the internal structure of an object is learned based on the analysis results for each analysis pattern measured in various measurement patterns using an auxiliary electrode and a plurality of low-potential electrodes (second to fourth electrodes) with different areas and positions. The various analysis patterns refer to various objects, such as the shape of the object, the size of the stage, the relative permittivity of the object, the number of relative permittivity values ​​of the object, and the distance from the center of the measuring device 2.

[0045] [Estimation method] Next, we will explain an example of an estimation method using Model 16. Figure 8 is a diagram illustrating the estimation method using the model according to this embodiment. As shown in Figure 8, during estimation, the supply unit 18 inputs the measurement results into the trained model 16. The trained model 16 estimates the internal information of the target object based on the input data. The measurement results are the capacitance between the first electrode 202 and the second electrode 205 for each rotation angle, the capacitance between the first electrode 202 and the third electrode 206 for each rotation angle, the capacitance between the first electrode 202 and the fourth electrode 207 for each rotation angle, the potential between the first electrode 202 and the second electrode 205 for each rotation angle, the potential between the first electrode 202 and the third electrode 206 for each rotation angle, the potential between the first electrode 202 and the fourth electrode 207 for each rotation angle, the loss between the first electrode 202 and the second electrode 205 for each rotation angle, the loss between the first electrode 202 and the third electrode 206 for each rotation angle, and the loss between the first electrode 202 and the fourth electrode 207 for each rotation angle.

[0046] [Example data used for model training] Next, we will explain an example of the data that Model 16 will be trained on. Furthermore, a comparison of the simulation results using analysis model 13 with the measurement results obtained using measurement device 2 confirmed that the trends in capacitance and potential for each rotation angle are very similar.

[0047] (Example 1) Figure 9 shows a first example of the data that the model according to this embodiment learns. In Figure 9, the horizontal axis is the rotation angle (degrees), and the vertical axis is the capacitance (μF). Figure 9 shows the simulation results for the object shown in Figure 2. There is one object, the relative permittivity of object 5 is 3, the distance d from the center point P to the center of object 5 is 30 (mm), and the diameter of object 5 is 30 (mm). The square and line g101 represent the capacitance between the first electrode and the second electrode, the circle and line g102 represent the capacitance between the first electrode and the third electrode, and the cross and line g103 represent the capacitance between the first electrode and the fourth electrode.

[0048] In this example, there are maximum capacitance values ​​between each electrode, ranging from approximately 150 degrees to 210 degrees of rotation. Furthermore, the rotation angle and capacitance at which these maximum capacitance values ​​occur differ for each electrode.

[0049] (Second example) Figure 10 shows an example of an object in the second example. The shape of object 5A is the same as object 5. The relative permittivity of object 5A is half 2 and the other half 3. In the simulation, object 5A is rotated while the relative permittivity of 3 is at the center.

[0050] Figure 11 shows a second example of the data learned by the model according to this embodiment. In Figure 11, the horizontal axis represents the rotation angle (degrees), and the vertical axis represents the capacitance (μF). The distance d from the center point P to the center of object 5A is 30 mm, and the diameter of object 5A is 30 mm. Figure 11 includes the simulation results for an object with a dielectric ratio of 2, the simulation results for objects with dielectric ratios of 2 and 3, and the simulation results for an object with a dielectric ratio of 3.

[0051] Line g151 represents the capacitance between the first and second electrodes, both having a relative permittivity of 3; line g152 represents the capacitance between the first and third electrodes, both having a relative permittivity of 3; and line g153 represents the capacitance between the first and fourth electrodes, both having a relative permittivity of 3. Line g161 represents the capacitance between the first and second electrodes, with relative permittivity of 2 and 3; line g162 represents the capacitance between the first and third electrodes, with relative permittivity of 2 and 3; and line g163 represents the capacitance between the first and fourth electrodes, with relative permittivity of 2 and 3. Line g171 represents the capacitance between the first and second electrodes, both having a relative permittivity of 2; line g172 represents the capacitance between the first and third electrodes, both having a relative permittivity of 2; and line g173 represents the capacitance between the first and fourth electrodes, both having a relative permittivity of 2.

[0052] As shown in Figure 11, the capacitance differs depending on the ratio of the materials, and for each case where multiple relative permittivity values ​​are present.

[0053] (Third example) Figure 12 shows an example of the results of potential analysis. In Figure 12, the horizontal axis represents the rotation angle (degrees), and the vertical axis represents the potential (V). In potential analysis, as shown in Figure 13, the object to be analyzed is rotated, and the potential is analyzed for each angle. Figure 13 is a diagram to explain the rotation angle of the object to be analyzed in potential analysis. Figure 13 shows examples where the rotation angle of the object is 0 degrees (g251) and 90 degrees (g252). Also, the example analysis results in Figure 12 are an example where the object is composed of two elements with relative permittivity values ​​of 2 and 3, as shown in Figure 13.

[0054] In the example in Figure 12, when the rotation angle is 75 degrees, a difference in potential occurs depending on the orbital angle of the object (0, 10, 20, 30, 40, 50, 60, 70, 80, 90 degrees) (g201). For example, when the rotation angle of the object changes by 10 degrees, the potential decreases by approximately 0.002 V. In this way, a difference in potential occurs due to the relative permittivity.

[0055] Figure 14 shows an example of the analysis results of the potential for each dielectric constant when the rotation angle of an object is around 180 degrees. The horizontal axis represents the angle at the measurement point, and the vertical axis represents the potential. The dashed line g301 represents the analysis result when the relative permittivity of the object is 2, line g302 represents the analysis result when the relative permittivity of the object is 3, and the dashed line g303 represents the analysis results when the relative permittivity of the object is both 2 and 3. As shown in Figure 14, a difference in potential occurs depending on the relative permittivity.

[0056] (Fourth example) Next, we will explain the case where an object is composed of multiple dielectrics. In the first to third examples, there was only one dielectric, but there may be two or more dielectrics. Figure 15 is a diagram illustrating an analytical model for an object composed of multiple dielectrics. Images g350 and g360 in Figure 15 show examples with two dielectrics of different sizes and different arrangements. In image g350, dielectrics 350a and 350b are spaced 180 degrees apart. In image g360, dielectrics 350c and 350d are spaced 90 degrees apart.

[0057] Figure 16 shows the analysis results of image g350 from Figure 15. The horizontal axis represents the rotation angle (degrees), and the vertical axis represents the capacitance (μF). Line g401 represents the capacitance between the first electrode and the second electrode, line g402 represents the capacitance between the first electrode and the third electrode, and line g403 represents the capacitance between the first electrode and the fourth electrode.

[0058] Figure 17 shows the analysis results of image g360 from Figure 15. The horizontal axis represents the rotation angle (degrees), and the vertical axis represents the capacitance (μF). Line g411 represents the capacitance between the first electrode and the second electrode, line g412 represents the capacitance between the first electrode and the third electrode, and line g413 represents the capacitance between the first electrode and the fourth electrode.

[0059] In the case of Figure 16, the largest capacitance value g405 appears at approximately 220 degrees, and the second largest capacitance value g406 appears at approximately 30 degrees. In the case of Figure 17, the largest capacitance value g415 appears at approximately 220 degrees, and the second largest capacitance value g416 appears at approximately 120 degrees. Here, when dielectrics 350a and 350c have equal relative permittivity and equal magnitude, and dielectrics 350b and 350d have equal relative permittivity and equal magnitude, differences can be observed in how multiple maximum values ​​appear, as well as in the difference between the maximum and minimum values, as shown in Figures 16 and 17.

[0060] [Processing procedure for the internal structure estimation device] Next, an example of the processing procedure for the internal structure estimation device 1 will be described. Figure 18 is a flowchart of the processing procedure of the internal structure estimation device according to this embodiment.

[0061] (Step S1) During learning, the internal structure estimation device 1 performs simulations of numerous patterns regarding the assumed internal information and uses the analysis model 13 to calculate analysis results (for example, capacitance and loss for each rotation angle, and potential at each circumferential position) using the finite element method.

[0062] (Step S2) During learning, the internal structure estimation device 1 associates the analysis results calculated by the simulation with the internal information of the object and trains the model 16 accordingly.

[0063] (Step S3) During estimation, the internal structure estimation device 1 measures the capacitance and loss and the potential at each circumferential position for each rotation angle of the target object whose internal information is unknown, using the measuring device 2.

[0064] (Step S4) During estimation, the internal structure estimation device 1 acquires the measurement results and inputs the acquired measurement results into the trained model 16 to estimate information about the internal structure of the target object (e.g., the distribution of dielectric constant).

[0065] (Step S5) During estimation, the internal structure estimation device 1 outputs information regarding the estimated internal structure of the target object.

[0066] Next, we will explain an example of the processing procedure during actual measurement. Figure 19 is a flowchart of the processing procedure during actual measurement according to this embodiment.

[0067] (Step S11) The measuring device 2 initializes the rotation angle (0 degrees) (reference position).

[0068] The measuring device 2 adds 6 degrees to the rotation angle, for example (step S12). The measuring device 2 measures the capacitance and spatial potential (step S13).

[0069] (Step S14) The measuring device 2 determines whether the rotation angle is greater than 360 degrees. If the measuring device 2 determines that the rotation angle is greater than 360 degrees (Step S14; YES), it terminates the process. If the measuring device 2 determines that the rotation angle is 360 degrees or less (Step S14; NO), it returns to the process in Step S12.

[0070] Note that the process shown in Figure 19 is just one example and is not limited to this. For example, the angle added in step S12 may be 5 degrees or less, or 7 degrees or more.

[0071] Furthermore, the internal structure estimation device 1 may perform simulations during training by carrying out the same processing as shown in Figure 19.

[0072] The examples described above illustrate how potential and loss are used in addition to capacitance for training Model 16, but this is not the only example. The data used for training Model 16 only needs to include at least one of potential and loss, or it may include other elements as well. Similarly, while we have described examples where potential and loss are used as data in addition to capacitance for estimation, this is not the only example. The data used for estimation only needs to be at least one of potential and loss, or it may include other elements.

[0073] As shown in Figures 9, 11, 12, 14, 16, and 17, the change in capacitance with respect to rotation angle and the change in potential with respect to rotation angle differ depending on the shape, arrangement, and relative permittivity of the object. Therefore, in this embodiment, various patterns such as the shape, size, arrangement, and number of dielectrics are simulated using the analysis model 13, and the analysis results are used to train model 16. According to this embodiment, by using the trained model 16, it is possible to estimate information about the internal structure of the target object (for example, the distribution of dielectric constant).

[0074] In the examples described above, as shown in Figures 9, 11, 12, 14, 16, and 17, measurement results for all rotation angles are used for both learning and estimation. However, the method is not limited to this. For example, in the case of a single dielectric material with a single relative permittivity and a cylindrical shape, as shown in Figure 2, the maximum values ​​between each electrode may be learned from the simulation results, and the maximum values ​​from the measurement results may be supplied to Model 16 for estimation. Alternatively, if there are multiple maximum values, multiple maximum values ​​between each electrode may be learned from the simulation results, and multiple maximum values ​​from the measurement results may be supplied to Model 16 for estimation. Alternatively, at least one maximum value and at least one minimum value between each electrode may be learned from the simulation results during learning and estimation, and at least one maximum value and at least one minimum value from the measurement results may be supplied to Model 16 for estimation. Alternatively, during training and estimation, the maximum value, minimum value, and the difference between the maximum and minimum values ​​between each electrode from the simulation results may be trained, and during estimation, the maximum value, minimum value, and the difference between the maximum and minimum values ​​from the measurement results may be supplied to Model 16 for estimation.

[0075] The objects mentioned above include, for example, parts of living organisms and concrete pillars. For instance, if the object is a living organism, estimating the distribution of dielectric constant within the object can be applied to the diagnosis of organ shape, visceral fat, malignant tumors, etc.

[0076] Furthermore, a program to implement all or part of the functions of the internal structure estimation device 1 in this invention may be recorded on a computer-readable recording medium, and all or part of the processing performed by the internal structure estimation device 1 may be performed by loading the program recorded on this recording medium into a computer system and executing it. Herein, "computer system" includes hardware such as an OS and peripheral devices. Furthermore, "computer system" also includes a WWW system equipped with a homepage provisioning environment (or display environment). Furthermore, "computer-readable recording medium" refers to portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and storage devices such as hard disks built into a computer system. Moreover, "computer-readable recording medium" also includes volatile memory (RAM) inside a computer system that acts as a server or client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line, which holds the program for a certain period of time.

[0077] Furthermore, the above program may be transmitted from a computer system that stores the program in a memory device or the like to another computer system via a transmission medium or by transmission waves within the transmission medium. Here, the "transmission medium" for transmitting the program refers to a medium that has the function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. In addition, the above program may be for the purpose of realizing a part of the functions described above. Furthermore, it may be a so-called differential file (differential program) that can realize the functions described above in combination with a program already recorded in the computer system.

[0078] Although embodiments for carrying out the present invention have been described above using examples, the present invention is not limited in any way to these embodiments, and various modifications and substitutions can be made without departing from the spirit of the present invention. [Explanation of Symbols]

[0079] 1...Internal structure estimation device, 11...Condition acquisition unit, 12...Calculation unit, 13...Analysis model, 14...Learning unit, 15...Model storage unit, 16...Model, 17...Acquisition unit, 18...Supply unit, 19...Output unit

Claims

1. A measurement result acquisition unit that acquires measurement results including at least the capacitance and potential of the target object, A supply unit provides the measurement results to a trained model that has learned the correspondence between the analysis results of the capacitance and potential of the object, which were analyzed using an analysis model that includes the internal structure of the object, and information about the internal structure of the object. Based on the previously trained model given the measurement results, an output unit estimates the internal structure of the target object and outputs the estimated result. An internal structure estimation device equipped with the following features.

2. The internal structure estimation device according to claim 1, wherein the analysis results are obtained by analyzing the analysis model using the finite element method.

3. The analysis results show the relationship between the rotation angle from the reference position when the object is rotated around the axis of rotation in the analysis model, when the measuring electrodes are placed at a predetermined position, and the capacitance measurement results by the measuring electrodes for each rotation angle. An internal structure estimation device according to claim 1 or claim 2.

4. The measuring electrode includes a high-potential electrode and a plurality of low-potential electrodes with different areas and lower potentials than the high-potential electrode. The rotation axis is positioned in the space where the high-potential electrode and the plurality of low-potential electrodes face each other. The analysis results are obtained by rotating the object placed in the space around the axis of rotation in the analysis model. The internal structure estimation device according to claim 3.

5. The analysis results include the potential between the high-potential electrode and the low-potential electrode, and the loss between the high-potential electrode and the low-potential electrode. The internal structure estimation device according to claim 4.

6. The measurement results include the capacitance measured by a measuring device, where the measuring electrode positioned at a predetermined location includes a high-potential electrode and a plurality of low-potential electrodes with different areas and lower potentials than the high-potential electrode, and the axis of rotation for rotating the target object is positioned in the space where the high-potential electrode and the plurality of low-potential electrodes face each other. An internal structure estimation device according to any one of claims 1 to 5.

7. The measurement result acquisition unit acquires measurement results including at least the capacitance and potential of the target object. The supply unit provides the measurement results to a trained model in which the correspondence between the analysis results of the capacitance and potential of the object, which were analyzed using an analysis model that includes the internal structure of the object, and information regarding the internal structure of the object has been learned. The output unit estimates the internal structure of the target object based on the learned model given the measurement results, and outputs the estimated result. Internal structure estimation method.

8. On the computer, Obtain measurement results including at least the capacitance and potential of the target object. The measurement results are then fed to a trained model that has learned the correspondence between the analysis results of the capacitance and potential of the object, which were analyzed using an analysis model that includes the internal structure of the object, and information about the internal structure of the object. Based on the previously trained model given the measurement results, the internal structure of the target object is estimated, and the estimated result is output. program.

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