Patent Application
20230214558
The present invention relates to a construction repair support apparatus, a construction repair support method, and a construction repair support program and specifically relates to a technique for presenting the determination basis for repair design information for a construction when the repair design information is automatically generated.
To address labor shortages and increased costs caused by obligated inspections of constructions including bridges and tunnels, ICT (Information and Communication Technology) are being increasingly used in maintenance of constructions.
For example, automatic generation of repair design information by using artificial intelligence (AI) and by learning structural data, damage data, and repair data of constructions is being studied.
When repair design information is automatically generated by using a computer, it is difficult to search for the determination basis for the repair design information, and the details of processing specifically in machine learning and AI are a black box, and therefore, the process of determination is unknown and the user is unable to understand and be convinced of the repair design information, which is a problem.
In the related art, an inference apparatus that infers a class among predetermined classes to which an input image belongs, by inference using a neural network has been proposed (JP2019-82883A).
The inference apparatus includes: an input unit; a frequently appearing feature value database in which frequently appearing feature values that frequently appear in an inference process in a neural network are classified into classes and stored; an inference unit that infers a class to which an input image belongs, by inference using the neural network; a representative feature value extraction unit that extracts feature values appearing in an inference process in the inference and extracts feature values, among the feature values, that satisfy a predetermined condition as representative feature values; a basis feature value extraction unit that extracts basis feature values on the basis of the frequently appearing feature values and the representative feature values; and an output unit that outputs the basis feature values together with the inferred class.
The basis feature value extraction unit extracts the intersection of two sets, namely, the set of the frequently appearing feature values and the set of the representative feature values, as the basis feature values.
For the inference apparatus described in JP2019-82883A, the frequently appearing feature value database in which frequently appearing feature values that frequently appear are classified into classes and stored needs to be prepared. Further, JP2019-82883A does not describe automatic generation of repair design information for a construction or indicate a new issue that, specifically when repair design information is automatically generated, the user is unable to understand and be convinced of the determination basis for the repair design information.
In one embodiment of the technique of the present disclosure, there are provided a construction repair support apparatus, a construction repair support method, and a construction repair support program with which repair design information for a construction can be automatically generated and the determination basis for the repair design information can be presented to the user.
A construction repair support apparatus according to a first aspect of the present invention is a construction repair support apparatus including a processor, the processor being configured to perform an information acquisition process of acquiring construction information concerning a construction, a repair design information generation process of generating repair design information concerning a repair of damage in the construction on the basis of the construction information and damage information concerning the damage in the construction, a determination basis generation process of generating information that contributes to generation of the repair design information, as determination basis information for the repair design information, and a display process of causing a display device to display the repair design information and the determination basis information.
According to the first aspect of the present invention, when repair design information concerning a repair of damage in a construction is automatically generated, determination basis information that is information contributing to generation of the repair design information is generated and the determination basis information is presented, and therefore, the user can easily understand the determination basis for the repair design information.
In the construction repair support apparatus according to a second aspect of the present invention, preferably, the processor is configured to acquire positional information about the damage in the construction, and cause the display device to display the repair design information in association with the positional information. Accordingly, the user can grasp the position of the damage in the construction to which the repair design information corresponds.
In the construction repair support apparatus according to a third aspect of the present invention, preferably, the construction information includes three-dimensional information that indicates the entire construction, and the processor is configured to cause the display device to display the construction three-dimensionally on the basis of the three-dimensional information, and cause the repair design information to be displayed at a corresponding position on the three-dimensionally displayed construction, on the basis of the positional information about the damage.
Accordingly, the user can grasp the position of the damage to which the repair design information corresponds, on the three-dimensionally displayed construction.
In the construction repair support apparatus according to a fourth aspect of the present invention, preferably, the processor is configured to perform a process of accepting switching between overall display and local display of the construction, and the processor is configured to in response to accepting switching from the overall display to the local display and the positional information about the damage, switch display on the display device from the overall display of the construction based on the three-dimensional information to the local display that includes an image of a position indicated by the positional information about the damage, and cause the display device to display the determination basis information associated with the positional information about the damage, and in response to accepting switching from the local display to the overall display, switch display on the display device to the overall display, and cause the display device to display the repair design information in association with the positional information about the damage.
According to the fourth aspect of the present invention, display can be switched between the overall display of the construction based on the three-dimensional information and the local display, and the user can confirm on the overall display, the repair design information associated with the positional information about the damage and can confirm the determination basis information for the repair design information on the local display.
Preferably, the construction repair support apparatus according to a fifth aspect of the present invention further includes a database that stores the construction information and the damage information, in which the processor is configured to perform a damage information generation process of generating the damage information on the basis of a two-dimensional image of the construction included in the construction information, and store the damage information in the database in association with the construction information, and in the information acquisition process, the construction information and the damage information associated with the construction information are acquired from the database.
Preferably, the construction repair support apparatus according to a sixth aspect of the present invention further includes a database that stores the construction information, in which in the information acquisition process, the construction information is acquired from the database, and in the repair design information generation process, the damage information is generated on the basis of a two-dimensional image of the construction included in the construction information, the construction information being acquired in the information acquisition process, and the repair design information concerning a repair of the damage in the construction is generated on the basis of the construction information and the damage information.
In the construction repair support apparatus according to a seventh aspect of the present invention, preferably, in response to acquiring a plurality of pieces of determination basis information including the determination basis information, the processor is configured to calculate pieces of degree-of-contribution information that respectively indicate percentages of contribution of the plurality of pieces of determination basis information to generation of the repair design information, and cause the display device to display the pieces of degree-of-contribution information respectively corresponding to the plurality of pieces of determination basis information. Accordingly, the user can confirm which piece of determination basis information contributes to generation of the repair design information to what degree and can reflect the confirmation to, for example, a repair method.
In the construction repair support apparatus according to an eighth aspect of the present invention, preferably, the determination basis information includes region information about a region, on the construction, to which attention is to be paid. The region information, about a region on the construction, contributing to generation of the repair design information can be presented as basis information for the repair design information.
In the construction repair support apparatus according to a ninth aspect of the present invention, preferably, in the repair design information generation process, the repair design information is generated on the basis of pieces of damage information at a plurality of time points, and the determination basis information includes a degree of a change over time in the pieces of damage information between the plurality of time points. Accordingly, the degree of development of damage can be used as basis information for the repair design information.
In the construction repair support apparatus according to a tenth aspect of the present invention, preferably, the processor is configured to perform a process of accepting specifying of the repair design information by a user, and in response to accepting specifying of the repair design information, cause the display device to display the determination basis information corresponding to the repair design information.
In the construction repair support apparatus according to an eleventh aspect of the present invention, preferably, the processor is configured to perform a process of accepting specifying of the determination basis information by a user, and in response to accepting specifying of the determination basis information, cause the display device to display the repair design information corresponding to the determination basis information.
In the construction repair support apparatus according to a twelfth aspect of the present invention, the processor includes a first learning model configured to perform the repair design information generation process, and the first learning model outputs the repair design information in response to input of the construction information or input of the construction information and the damage information.
In the construction repair support apparatus according to a thirteenth aspect of the present invention, preferably, in the determination basis generation process performed by the processor, a calculation process for an output result of the first learning model is traced back and the determination basis information that affects the output result is extracted.
In the construction repair support apparatus according to a fourteenth aspect of the present invention, the processor includes a second learning model configured to perform the damage information generation process, and the second learning model outputs the damage information about the construction in response to input of a two-dimensional image of the construction.
In the construction repair support apparatus according to a fifteenth aspect of the present invention, preferably, the construction information includes at least one of drawing information about the construction, three-dimensional information that indicates the entire construction, a two-dimensional image that shows a local part of the construction, or text information concerning the construction.
In the construction repair support apparatus according to a sixteenth aspect of the present invention, preferably, the construction information includes at least one of structural information, repair history information, environmental information, or monitoring information about the construction.
In the construction repair support apparatus according to a seventeenth aspect of the present invention, preferably, the repair design information includes at least one of a cause of damage, a countermeasure method, a degree of soundness, necessity of repair, degradation prediction, or a countermeasure category.
In the construction repair support apparatus according to an eighteenth aspect of the present invention, preferably, the determination basis information includes at least one of the damage information, the construction information, or environmental information.
In the construction repair support apparatus according to a nineteenth aspect of the present invention, preferably, the damage information includes at least one of a damage type, a damage shape, a degree of damage, a degree of development of damage, a damaged region, a damage position, or similar damage.
A construction repair support method according to a twentieth aspect of the present invention is a construction repair support method for a processor to perform a step of acquiring construction information concerning a construction, a step of generating repair design information concerning a repair of damage in the construction on the basis of the construction information and damage information concerning the damage in the construction, a step of generating information that contributes to generation of the repair design information, as determination basis information for the repair design information, and a step of causing a display device to display the repair design information and the determination basis information.
A construction repair support program according to a 21st aspect of the present invention is a construction repair support program for causing a computer to implement a function of acquiring construction information concerning a construction, a function of generating repair design information concerning a repair of damage in the construction on the basis of the construction information and damage information concerning the damage in the construction, a function of generating information that contributes to generation of the repair design information, as determination basis information for the repair design information, and a function of causing a display device to display the repair design information and the determination basis information.
According to the present invention, when repair design information for a construction is automatically generated, the determination basis for the repair design information can be presented. Accordingly, the user can understand and be convinced of the automatically generated repair design information and can refer to the determination basis for the repair design information upon a repair of the construction.
Hereinafter, preferred embodiments of a construction repair support apparatus, a construction repair support method, and a construction repair support program according to the present invention will be described with reference to the attached drawings.
As illustrated in
The processor 10 is formed of a CPU (central processing unit) and so on, centrally controls units of the construction repair support apparatus 1, and functions as, for example, an information acquisition unit (input unit) 20, a repair design information generation unit 22, and a determination basis generation unit 24 illustrated in
The repair design information generation unit 22 is a unit that generates repair design information concerning a repair of damage in a construction, on the basis of, for example, construction information concerning the construction, and the determination basis generation unit 24 is a unit that generates information contributing to generation of the repair design information, as determination basis information for the repair design information. The repair design information generation unit 22, the determination basis generation unit 24, and so on will be described in detail below.
The memory 11 includes a flash memory, a ROM (read-only memory), and a RAM (random access memory). The flash memory and the ROM are nonvolatile memories that store, for example, an operating system and various programs including a construction repair support program according to the present invention. The RAM functions as a work area for processing by the processor 10. The RAM temporarily stores, for example, the construction repair support program stored in, for example, the flash memory. Note that the processor 10 may include a part (RAM) of the memory 11.
The processor 10 controls the units of the construction repair support apparatus 1 and performs processes in accordance with the construction repair support program while using the RAM as a work area.
The database 12 is a unit that stores and manages information concerning constructions. Here, information concerning constructions include construction information concerning constructions and damage information concerning damage in constructions. The construction information and the damage information in this example will be described in detail below.
The output unit 14 is a display device that displays repair design information generated by the construction repair support apparatus 1 and determination basis information that contributes to generation of the repair design information. The output unit 14 performs overall display of, for example, a three-dimensional image that shows the entire construction, local display of a two-dimensional image that shows a local part of a construction, and display of, for example, a damage image and a damage diagram, and is further used as part of a user interface for accepting an instruction from the user.
The input/output interface 16 includes a connection unit that can be connected to an external device and a communication unit that can be connected to a network. To the connection unit that can be connected to an external device, for example, USB (Universal Serial BUS) or HDMI (High-Definition Multimedia Interface) (HDMI is a registered trademark) can be applied.
The construction repair support apparatus 1 can acquire, for example, construction information concerning a desired construction and damage information concerning damage in the construction through the input/output interface 16. When necessary information can be acquired through the input/output interface 16, the database 12 might not be used.
The operation unit 18 includes a keyboard and a pointing device such as a mouse and functions as a user interface for accepting various items specified by the user. The operation unit 18 may include a touch panel.
The construction repair support apparatus of the first embodiment illustrated in
The information acquisition unit 20 that functions as an input unit acquires from the database 12, construction information concerning a desired construction and damage information concerning damage in the construction in accordance with a selection instruction from the user.
Construction information includes at least one of drawing information (for example, CAD (computer-aided design) information) about a construction, three-dimensional information that indicates the entire construction, a two-dimensional image (captured image) that shows a local part of a construction, or text information concerning a construction. Three-dimensional information is, for example, a three-dimensional image, three-dimensional CAD information, or three-dimensional point cloud data.
Further, construction information includes at least one of structural information, repair history information, environmental information, or monitoring information about a construction.
Examples of structural information and so on about a construction when the construction is a bridge are listed below.
Damage information concerning damage in a construction includes at least one of the damage type, the damage shape, the degree of damage, the degree of development of damage, the damaged region, the damage position, or similar damage.
Examples of damage types are listed below.
The repair design information generation unit 22 generates repair design information concerning a repair of damage in a construction on the basis of construction information concerning the construction and damage information acquired by the information acquisition unit 20.
Repair design information includes at least one of the cause of damage in a construction, a countermeasure method, the degree of soundness, the necessity of repair, degradation prediction, or a countermeasure category.
The types of the cause of damage include fatigue, salt damage, frost damage, an alkali-aggregate reaction, and neutralization in a case of concrete members and fatigue and material degradation in a case of steel members.
Examples of a countermeasure method include a pouring-into-crack method, a concrete protection method, a cross-section repair method, an electric anticorrosion method, and floor slab concrete re-pouring work.
As indicators of the degree of soundness, various indicators are specified by the country and local governments and, for example, indicators indicating diagnosis results at four levels from I to IV are specified in the road/bridge periodic inspection guidelines (February, 2019) established by the Ministry of Land, Infrastructure, Transport and Tourism.
As a countermeasure category, for example, the following categories are specified in the bridge periodic inspection guidelines (March, 2019) established by the Ministry of Land, Infrastructure, Transport and Tourism.
Although usually a person in charge of diagnosis visually inspects a damaged location of a construction in proximity to the construction, conducts a hammering test or other tests as necessary, and creates from the damage state and so on, repair design information (inference of the cause of damage, selection of a countermeasure method, determination of the degree of soundness, determination of the necessity of repair, degradation prediction, selection of a countermeasure category, and so on), the repair design information generation unit 22 in the present invention automatically generates repair design information on the basis of construction information and damage information concerning the construction.
The repair design information generation unit 22 can be formed of, for example, a trained model (first learning model) for which machine learning has been performed by using data sets of learning data including pairs of construction information and damage information, and repair design information corresponding to the construction information and damage information, and in response to input of construction information and damage information, outputs repair design information corresponding to the construction information and damage information as an inference result. Note that the repair design information generation unit 22 need not automatically generate repair design information by the first learning model and may automatically generate repair design information with an algorithm for generating repair design information.
The determination basis generation unit 24 extracts and generates information that contributes to generation of the repair design information by the repair design information generation unit 22, as determination basis information for the repair design information. The determination basis information includes at least one of damage information, construction information, or environmental information.
The repair design information generated by the repair design information generation unit 22 is output to the output unit 14 and displayed in a repair design determination result presentation section 14A of the output unit 14.
Similarly, the determination basis information generated by the determination basis generation unit 24 is output to the output unit 14 and displayed in a repair design determination basis presentation section 14B of the output unit 14.
Note that in
Further, in the first embodiment of the construction repair support apparatus, the database 12 need not be provided, and the information acquisition unit 20 can acquire necessary information from an external device or a network through the input/output interface 16.
Although only with the repair design information presented in the repair design determination result presentation section 14A, the user may be unable to understand or be convinced of the determination basis for the repair design information, when repair design determination basis information is presented together with the repair design determination result as described above, the user can understand or be convinced of the determination basis for the repair design information.
In
The CNN 22A infers repair design information concerning damage in the construction from features of the damage image 30 and outputs a determination result (repair design information). The damage image 30 in this example is a captured image 34 of a construction in which concrete cracks 36 occur along a steel member 32 (or a captured image on which a damage diagram showing cracks is superimposed and displayed), and the determination result is neutralization 38. The neutralization 38 is one of the causes of degradation (classes) and has external appearance features including cracks, rust, and concrete peeling along the axial direction of a steel member.
The CNN 22A outputs the neutralization 38 as the determination result from the above-described feature of the damage image 30.
In
As the heat map creation method, various methods are available and when, for example, Grad-CAM (Gradient-weighted Class Activation Mapping) is used, the gradient is calculated backward so as to maximize the probability value of the neutralization 38 that is the determination result and the heat map 39 is obtained as the determination basis for the neutralization 38. Alternatively, CAM, which is a base method for Grad-CAM, can be used. Further, as another method for creating a heat map (visualizing a region to which attention is to be paid) by the CNN, Attention is available.
In the heat map 39 illustrated in
Therefore, the neutralization 38 can be presented as repair design information, and the heat map 39 can be presented as determination basis information therefor.
A heat map for a cause of degradation other than the neutralization 38 can be similarly calculated.
Further, a determination result and the determination basis can be cross-referenced to each other.
In
In response to the user giving an instruction for selecting a point (coordinates) on the heat map 39 or 41 presented in the determination basis presentation section 14B, the processor 10 can calculate estimated contribution percentages of the respective causes of degradation in accordance with the values on the heat map 39 or 41 and display the estimated contribution percentages in the determination result presentation section 14A together with the causes of degradation. For example, for a certain point on the heat map, 20% and 80% can be displayed for the neutralization and the ASR respectively.
Note that the method of presenting a determination basis as a heat map created by using, for example, Grad-CAM can be used for other than images.
In
As the determination basis for this determination result, a damage image 50 is presented, and as input information, text information concerning the construction, that is, a member (pavement) and a damage type (cracks), is presented.
In the first example of determination basis presentation, in response to acquiring a plurality of pieces of determination basis information for the degree of soundness III, the processor 10 calculates degree-of-contribution information that includes a degree of contribution indicating the percentage of contribution of each of the plurality of pieces of determination basis information to generation of the degree of soundness III, by using heat maps as described above. In this example, as pieces of degree-of-contribution information for the member and the state of damage, the processor 10 calculates a degree of contribution 80% for the member and a degree of contribution 20% for the state of damage and causes these pieces of degree-of-contribution information to be displayed.
In the example illustrated in
In the second example of determination basis presentation illustrated in
That is, as the determination basis for a determination result, the damage image 50 and a heat map 52 are displayed.
The heat map 52 is a heat map corresponding to the damage image 50 and obtained by the CNN 22A calculating the gradient backward so as to maximize the probability value of the determination result as illustrated in
In the third example of determination basis presentation illustrated in
In
“Floor slab concrete re-pouring work” is a repair method that is performed when the floor slab of a bridge is significantly damaged and the floor slab is unable to be satisfactorily maintained with temporary measures or a maintenance method.
The processor 10 causes the output unit 14 to display the text information 60 and text information 62 in which the extracted text is highlighted.
Although the text information 62 in which the extracted text is highlighted by boxing the extracted text is displayed in this example, alternatively, the extracted text may be highlighted by coloring the extracted text, for example, red. Instead of the text information 62, text information, such as “repair design information: floor slab concrete re-pouring work” and “determination basis information: peeling/exposure of reinforcing rods in floor slab”, may be generated and displayed.
Construction information includes three-dimensional information (in this example, a three-dimensional image) that indicates the entire construction, and the processor 10 can cause the output unit 14 to three-dimensionally display the construction on the basis of the three-dimensional image acquired by the information acquisition unit 20.
On the three-dimensional image in overall display, locations for which the determination results of repair design information are obtained are highlighted with, for example, indicators such as arrows and/or highlighting. The processor 10 can cause the output unit 14 to display, on the basis of positional information about a location for which the determination result is obtained, repair design information associated with the positional information.
Local display can be performed by displaying a two-dimensional image (in this example, the damage image 50) showing a local part of the construction.
As illustrated in
The processor 10 can switch between the overall display of the construction illustrated in
In response to accepting switching of display in the overall display state and positional information about damage to be locally displayed, the processor 10 switches display on the output unit 14 from the overall display (
For example, in response to the user operating the mouse and clicking on the position of damage, on the overall display screen, that is to be locally displayed (or on the display position of a determination result displayed in association with the position of damage), the processor 10 switches from the overall display (
In contrast, in response to accepting switching from the local display to the overall display in the local display state, the processor 10 switches from the local display (
Note that a user operation for switching between overall display and local display is not limited to the above-described operation method using a mouse. For example, when the operation unit 18 includes a touch panel, an instruction for switching between overall display and local display can be given by, for example, a tap operation and pinch-in and pinch-out operations on the touch panel.
In response to the user inputting a request for viewing the details of damage information on the local display screen (for example, in response to a click on “damage number 1” in
The local display is not limited to, for example, the damage image 50 that is a two-dimensional image and can be performed by enlarging a three-dimensional image that shows the entire construction and displaying a part of the three-dimensional image. Instead of a three-dimensional image, for example, overall display of a construction may be performed on the basis of other three-dimensional information, such as three-dimensional CAD (computer-aided design) data or three-dimensional point cloud data, about the construction.
Repair design information generated by the repair design information generation unit 22 illustrated in
In response to the user inputting an instruction for list display, the processor 10 can cause the output unit 14 to display the list as illustrated in
In response to the user inputting an instruction for specifying, for example, a member/damage type or a determination result for damage, the processor 10 can perform sorting for the list, and in response to a click on, for example, “floor slab damage number 1” on the list illustrated in
The construction repair support apparatus of the second embodiment illustrated in
In response to input of a captured image 34 of a construction, the damage information generation unit 42 generates, on the basis of the captured image 34, damage information including the type of damage in the construction present in the captured image 34, the damage shape, the degree of damage, the damaged region, and the damage position.
The damage information generation unit 42 can be formed of, for example, a trained model (third learning model) for which machine learning has been performed by using data sets of learning data including pairs of captured images of damage in constructions, and damage information concerning the damage in the captured images, and in response to input of the captured image 34 of a test target construction, outputs damage information concerning damage in the captured image as an inference result. Note that the damage information generation unit 42 need not automatically generate damage information by the third learning model and may automatically generate damage information with a detection algorithm for detecting damage information.
The damage information generated by the damage information generation unit 42 can be saved in the database 12 in association with construction information (for example, the captured image 34) corresponding to the damage information.
Further, repair design information generated by the repair design information generation unit 22 illustrated in
In
The processor 10 generates repair design information concerning a repair of the damage in the construction on the basis of the acquired construction information and damage information (step S20, repair design information generation process).
The processor 10 generates automatically or in response to an instruction for generation from the user, information that contributes to generation of the repair design information generated in step S20, as determination basis information for the repair design information (step S30, determination basis generation process).
The processor 10 outputs to and causes the output unit 14 to display the repair design information generated in step S20 and the determination basis information generated in step S30 (step S40, display process). Note that display of the repair design information and display of the determination basis information may be simultaneously performed on the same screen, or any one of the repair design information or the determination basis information may be displayed in accordance with a selection instruction from the user.
In the embodiments, the hardware configuration of the processing units including the CPU that perform various types of processing is implemented as various processors as described below. The various processors include a CPU (central processing unit) that is a general-purpose processor executing software (program) to function as various processing units, a programmable logic device (PLD), such as an FPGA (field-programmable gate array), that is a processor for which the circuit configuration can be changed after manufacturing, and a dedicated electric circuit, such as an ASIC (application-specific integrated circuit), having a circuit configuration that is designed only for performing a specific process.
One processing unit may be configured as one of the various processors or two or more processors of the same type or different types (for example, a plurality of FPGAs or a combination of a CPU and an FPGA). Further, a plurality of processing units may be configured as one processor. As the first example of configuring a plurality of processing units as one processor, a form is possible in which one or more CPUs and software are combined to configure one processor, and the processor functions as the plurality of processing units, a representative example of which is a computer, such as a client or a server. As the second example thereof, a form is possible in which a processor is used in which the functions of the entire system including the plurality of processing units are implemented as one IC (integrated circuit) chip, a representative example of which is a system on chip (SoC). As described above, regarding the hardware configuration, the various processing units are configured by using one or more of the various processors described above.
Further, the hardware configuration of the various processors is more specifically an electric circuit (circuitry) in which circuit elements, such as semiconductor elements, are combined.
Further, the present invention includes the construction repair support program that is installed in a computer to thereby cause the computer to function as the construction repair support apparatus according to the present invention, and a nonvolatile storage medium to which the construction repair support program is recorded.
Further, the present invention is not limited to the above-described embodiments and various modifications can be made without departing from the spirit of the present invention as a matter of course.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-160940 | Sep 2020 | JP | national |
The present application is a Continuation of PCT International Application No. PCT/JP2021/034507 filed on Sep. 21, 2021 claiming priority under 35 U.S.C § 119(a) to Japanese Patent Application No. 2020-160940 filed on Sep. 25, 2020. Each of the above applications is hereby expressly incorporated by reference, in its entirety, into the present application.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2021/034507 | Sep 2021 | US |
| Child | 18183779 | US |
