Seismic intensity estimation device

Abstract

To provide a seismic intensity estimation device capable of accurately estimating the seismic intensity at a vehicle position even when the vehicle is not on the surface of the earth itself but located on a structure that exists on the surface of the earth.SOLUTION: A seismic intensity estimation unit 22 is configured to receive earthquake information indicating the occurrence and scale of earthquakes and estimates the ground seismic intensity at the current location of the vehicle based on ground characteristics information representing ground characteristics at the current position of the vehicle and the earthquake information. When the vehicle is on an elevated road, bridge, etc., the seismic intensity estimation unit 22, estimates the seismic intensity at the position of the vehicle on the structure based on seismic intensity on the surface and the vibration characteristics of the structure. An output unit 24 transmits the estimated seismic intensity information indicating the estimated earthquake intensity to vehicles and a vehicle operation system and the like.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a technique for estimating the seismic intensity at the position of a vehicle when an earthquake occurs.

Background Art

[0002] Patent Document 1 describes a system for obtaining the seismic intensity in the area where a vehicle is traveling. Based on earthquake information, ground information, and the position information of the moving object, the system calculates the seismic intensity predicted in the area including the position of the moving object and the time when the earthquake reaches the area.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the system described in Patent Document 1, the seismic intensity on the ground surface can be estimated. However, in this system, it only estimates the seismic intensity on the ground surface in consideration of the characteristics of the ground. Therefore, when a vehicle is on a structure such as an elevated road or a bridge, the seismic intensity at the position of the vehicle on the structure cannot be accurately estimated.

[0005] An object of the present disclosure is to accurately estimate the seismic intensity at the position of a vehicle even when the vehicle is not on the ground surface itself but on a structure existing on the ground surface.

Means for Solving the Problems

[0006] One aspect of the present disclosure is A depth estimation device for estimating seismic intensity at the location of a vehicle, earthquake information indicating the occurrence and magnitude of an earthquake Received to do Receiving unit and A vehicle location management unit that acquires information indicating the current location of the vehicle, the magnitude of the earthquake indicated by the earthquake information, At the current location of the aforementioned vehicle ground characteristics toni Based on the above vehicle the current In terms of location Earth's surface Seismic intensity estimation Department and, The seismic intensity estimation unit refers to a structural location database that stores structural location information indicating the location of a structure, determines whether the vehicle is currently on the structure, and if it determines that the vehicle is currently on the structure, it acquires the vibration characteristics of the structure and estimates the seismic intensity at the vehicle's current location based on the seismic intensity of the ground and the acquired vibration characteristics. If it determines that the vehicle is not currently on the structure, it estimates the seismic intensity of the ground as the seismic intensity at the vehicle's current location. This is a seismic intensity estimation device characterized by the following features.

[0007] According to the above configuration, the seismic intensity is estimated by also considering the vibration characteristics of structures present on the ground at the vehicle's location. Therefore, compared to estimating the seismic intensity for a vehicle by considering only the characteristics of the ground, the seismic intensity at the vehicle's location can be estimated with greater accuracy.

[0008] The function of the seismic intensity estimation device may be implemented using artificial intelligence (AI). For example, machine learning such as deep learning may be used. Specific techniques that may be used include neural networks (e.g., convolutional neural networks (CNNs), recurrent neural networks (RNNs)), autocoding, backpropagation, or ensemble learning. Of course, the above configuration is not limited to these; any artificial intelligence technology may be applied. [Effects of the Invention]

[0009] According to this disclosure, even if a vehicle is not located directly on the ground surface but is located on a structure on the ground surface, the seismic intensity at the location of the vehicle can be estimated with high accuracy. [Brief explanation of the drawing]

[0010] [Figure 1] This is a block diagram showing the configuration of the seismic intensity estimation system according to the embodiment. [Figure 2] This is a flowchart showing the processing flow by the seismic intensity estimation device. [Figure 3] This is a diagram showing a database of structural locations. [Figure 4] This diagram illustrates the process for estimating the seismic intensity at a vehicle's location. [Modes for carrying out the invention]

[0011] Referring to Figure 1, the seismic intensity estimation system according to the embodiment will be described. Figure 1 is a block diagram showing the configuration of the seismic intensity estimation system according to the embodiment.

[0012] The seismic intensity estimation system according to this embodiment includes a seismic intensity estimation device 10, a ground characteristics DB (database) 12, a structure location DB 14, and a vibration characteristics DB 16.

[0013] The seismic intensity estimation device 10 is a device that estimates the seismic intensity at the location of a vehicle when an earthquake occurs. If the vehicle is located on a structure on the ground surface, the seismic intensity estimation device 10 estimates the seismic intensity at the location of the vehicle located on the structure.

[0014] The Ground Characteristics DB12 is a storage device (e.g., a hard disk drive or memory) that stores ground characteristics information. Ground characteristics refer to the magnitude of ground shaking when an earthquake occurs, for example, the ground amplification factor. The ground amplification factor is a numerical value that represents the magnitude of shaking when an earthquake occurs and indicates the weakness of the ground to earthquakes. The larger the ground amplification factor, the greater the ground shaking. For example, ground characteristics for each location or for each area may be calculated in advance, and ground characteristics information showing the ground characteristics for each location or for each area may be stored in the Ground Characteristics DB12. Alternatively, ground characteristics for each area corresponding to road divisions may be calculated, and ground characteristics information showing the ground characteristics for each division may be stored in the Ground Characteristics DB12.

[0015] The structure location DB14 is a storage device that stores structure location information indicating the location of structures. Structures include elevated structures and bridges built on the ground. The location of a structure may be determined by latitude and longitude, or by road division. For example, the presence and type of structures are predetermined for each road division. For each road division, the structure location DB14 stores in advance, linked with division identification information (e.g., division ID) to identify the road division, information indicating the presence or absence of structures in that division, and information indicating the type of structure present in that division.

[0016] The vibration characteristic DB 16 is a storage device that stores vibration characteristic information indicating the vibration characteristics of a structure. For example, the vibration characteristics are the natural period of the structure and the damping characteristics of vibration. The natural period and the damping characteristics of vibration of each structure are calculated in advance as vibration characteristics, and the vibration characteristic information of each structure is stored in the vibration characteristic DB 16 in advance. For example, the vibration characteristics of a structure may be calculated by analyzing the shaking when an earthquake occurred in the past. The vibration characteristics of a structure may be calculated based on the design data of the structure. Note that the vibration characteristic DB 16 may be included in the structure position DB 14.

[0017] The seismic intensity estimation device 10, the ground characteristic DB 12, the structure position DB 14, and the vibration characteristic DB 16 can communicate with each other via a communication path such as the Internet or a LAN (Local Area Network), for example. The seismic intensity estimation device 10 acquires information from the ground characteristic DB 12, the structure position DB 14, and the vibration characteristic DB 16 by wireless communication or wired communication. Note that at least one of the DBs of the ground characteristic DB 12, the structure position DB 14, and the vibration characteristic DB 16 may be included in the seismic intensity estimation device 10.

[0018] The seismic intensity estimation device 10 includes a reception unit 18, a vehicle position management unit 20, a seismic intensity estimation unit 22, and an output unit 24.

[0019] The reception unit 18 receives earthquake information when an earthquake occurs. For example, the earthquake information is an emergency earthquake bulletin or the like, and is information indicating the occurrence and scale of an earthquake. Specifically, the earthquake information includes information indicating the time when the earthquake occurred, information indicating the epicenter, information indicating the depth of the epicenter, information indicating the magnitude, information indicating the period of seismic motion (for example, long-period seismic motion) (the time required for one reciprocation of shaking), information indicating the seismic intensity at each observation point, the maximum acceleration of shaking at each observation point, the maximum velocity of shaking at each observation point, information indicating the maximum predicted seismic intensity at each location, and information indicating the time when shaking reaches each location, etc. For example, the earthquake information is transmitted from a national agency (for example, the Meteorological Agency or an earthquake research institution) or a private forecasting agency, etc. The reception unit 18 is composed of a communication device, a communication interface, etc., and receives earthquake information by wireless communication or wired communication.

[0020] The vehicle position management unit 20 receives vehicle position information indicating the position of the vehicle and manages the position of the vehicle. For example, the vehicle position information may be information indicating the current position of the vehicle acquired by GPS (Global Positioning System), or may be identification information (for example, section ID) of the road section on which the vehicle is currently traveling. For example, the vehicle position management unit 20 may receive vehicle position information from each vehicle to be managed, or may receive vehicle position information of each vehicle from a vehicle operation management system (for example, a system that acquires the position information of each vehicle and manages the operation of each vehicle).

[0021] The seismic intensity estimation unit 22 estimates the seismic intensity at the position of the vehicle. Specifically, when the receiving unit 18 receives earthquake information, the seismic intensity estimation unit 22 receives the earthquake information from the receiving unit 18 and acquires vehicle position information indicating the current position of the vehicle from the vehicle position management unit 20. The seismic intensity estimation unit 22 acquires ground characteristic information indicating the ground characteristics at the current position of the vehicle from the ground characteristic DB 12. The seismic intensity estimation unit 22 estimates the seismic intensity of the ground surface at the current position of the vehicle based on the earthquake information and the ground characteristic information. For example, the seismic intensity estimation unit 22 estimates the seismic intensity of the ground surface at the current position of the vehicle based on the ground amplification factor of the ground at the current position of the vehicle and the seismic intensity indicated by the earthquake information, etc.

[0022] For example, the seismic intensity estimation unit 22 estimates the seismic intensity at the ground surface using the known techniques described below. The seismic intensity estimation unit 22 estimates the maximum acceleration at the seismic bedrock (a surface assumed to be located at a certain depth underground) based on the maximum acceleration at the observation point indicated by the earthquake information and the ground amplification factor of the ground at that observation point. Similarly, the seismic intensity estimation unit 22 estimates the maximum velocity at the seismic bedrock based on the maximum velocity indicated by the earthquake information and the ground amplification factor of the ground at that observation point. The seismic intensity estimation unit 22 performs spatial interpolation on the maximum acceleration at the seismic bedrock and estimates the maximum acceleration at the ground surface at the vehicle's current position based on the maximum acceleration at the seismic bedrock and the ground amplification factor of the ground at the vehicle's current position. Similarly, the seismic intensity estimation unit 22 performs spatial interpolation on the maximum velocity at the seismic bedrock and estimates the maximum velocity at the ground surface at the vehicle's current position based on the maximum velocity at the seismic bedrock and the ground amplification factor of the ground at the vehicle's current position. The seismic intensity estimation unit 22 estimates the ground intensity at the vehicle's current position based on the maximum acceleration and maximum velocity using an empirical formula. This estimation process is merely an example, and the seismic intensity estimation unit 22 may estimate the ground intensity at the vehicle's current position using a different estimation process.

[0023] Furthermore, the seismic intensity estimation unit 22 refers to the structure location DB 14 and determines, based on the vehicle location information, whether or not a vehicle is currently on the structure. If a vehicle is on the structure, the seismic intensity estimation unit 22 obtains vibration characteristic information indicating the vibration characteristics of the structure from the vibration characteristic DB 16 and estimates the seismic intensity at the location of the vehicle on the structure based on the seismic intensity at the ground surface and the vibration characteristics of the structure. When the natural period of a structure matches the period of the earthquake motion, the shaking of the structure increases due to resonance. The seismic intensity estimation unit 22 estimates the seismic intensity at the location of the vehicle on the structure according to this rule. Specifically, the seismic intensity estimation unit 22 increases the seismic intensity the closer the natural period of the structure is to the period of the earthquake motion. For example, a coefficient is predetermined according to the degree of agreement between the natural period of the structure and the period of the earthquake motion. This coefficient is a value that increases as the natural period of the structure approaches the period of the earthquake motion. The seismic intensity estimation unit 22 estimates the seismic intensity at the location of the vehicle on the structure by multiplying the seismic intensity at the ground surface by a coefficient corresponding to the natural period of the structure on which the vehicle is located.

[0024] The output unit 24 outputs estimated seismic intensity information indicating the seismic intensity estimated by the seismic intensity estimation unit 22. For example, the output unit 24 may transmit the estimated seismic intensity information to the vehicle or navigation system via wireless or wired communication, or it may transmit the estimated seismic intensity information to the vehicle operation system. If the vehicle is on a structure, the output unit 24 outputs estimated seismic intensity information indicating the seismic intensity at the vehicle's location on the structure. If the vehicle is not on a structure, the output unit 24 outputs estimated seismic intensity information indicating the seismic intensity at the ground surface at the vehicle's current location.

[0025] For example, when estimated seismic intensity information is transmitted to a vehicle or navigation system, the estimated seismic intensity information may be displayed on a display installed in the vehicle or output as audio. If estimated seismic intensity information is transmitted to a vehicle operation system, the vehicle operation system may transmit the estimated seismic intensity information, warning information, or evacuation information to the vehicle. Furthermore, if the vehicle is an autonomous vehicle that does not require human intervention, the vehicle operation system may control the autonomous vehicle according to the estimated seismic intensity information. For example, the vehicle operation system may stop the autonomous vehicle or guide it to a specific location (e.g., the shoulder of the road).

[0026] For example, the seismic intensity estimation device 10 is a computer (e.g., a server or a personal computer). Some functions of the seismic intensity estimation device 10 may be implemented by other devices. In this case, the seismic intensity estimation device 10 and the other devices may constitute a system. Part or all of the seismic intensity estimation device 10 may be mounted on a vehicle. The seismic intensity estimation device 10 may be mounted on a vehicle operation system.

[0027] The following outlines the processing performed by the seismic intensity estimation device 10, with reference to Figure 2. Figure 2 is a flowchart showing the flow of this processing.

[0028] When the receiving unit 18 receives earthquake information (S01), the seismic intensity estimation unit 22 estimates the ground surface seismic intensity at the vehicle's current location based on ground characteristic information indicating the ground characteristics at the vehicle's current location and the earthquake information (S02). If the vehicle is on a structure (S03, Yes), the seismic intensity estimation unit 22 estimates the seismic intensity at the vehicle's location on the structure based on the ground surface seismic intensity and the vibration characteristics of the structure (S04). The output unit 24 outputs estimated seismic intensity information indicating the estimated seismic intensity (S05). If the vehicle is not on a structure (S03, No), the output unit 24 outputs estimated seismic intensity information indicating the ground surface seismic intensity (S05).

[0029] Furthermore, a function to perform the processing in steps S03 to S05 may be installed in the vehicle. For example, a seismic intensity estimation unit 22 and an output unit 24 may be installed in the vehicle, and the seismic intensity may be estimated and output.

[0030] The following describes in detail the processing performed by the seismic intensity estimation device 10.

[0031] Figure 3 shows an example of a structure location database. In the structure location database, each road section is associated with a section ID and information indicating the type of structure present in that section. In the example shown in Figure 3, the structures are elevated structures or bridges. For example, an elevated structure is located in section ID "124". A bridge is located in section ID "282". Elevated structures and bridges are not located in sections ID "251" and section ID "267". The seismic intensity estimation unit 22 refers to this structure location database to determine whether or not a structure exists in the section where a vehicle is located. The seismic intensity estimation unit 22 also identifies the structures located in the section where the vehicle is located.

[0032] Figure 4 shows a diagram illustrating the process for estimating the seismic intensity at a vehicle's location. Here, as an example, we assume the vehicle is located at one of the following locations: P1, P2, or P3. No structures are present on the ground at location P1. A bridge is present on the ground at location P2. An elevated structure is present on the ground at location P3.

[0033] If the vehicle is on the ground surface at position P1, the seismic intensity estimation unit 22 obtains ground characteristic information indicating the ground characteristics at position P1 from the ground characteristic DB 12. Based on the earthquake information and ground characteristic information, the seismic intensity estimation unit 22 estimates the ground surface seismic intensity at position P1 ("Estimated Ground Surface Seismic Intensity" in Figure 4). Since there are no structures on the ground surface at position P1, the output unit 24 outputs the estimated seismic intensity information indicating the estimated ground surface seismic intensity as information indicating the estimated seismic intensity at the vehicle's position.

[0034] If the vehicle is located on a bridge on the ground surface at location P2, the seismic intensity estimation unit 22 obtains ground characteristic information indicating the ground characteristics at location P2 from the ground characteristic DB 12. Based on the earthquake information and ground characteristic information, the seismic intensity estimation unit 22 estimates the ground surface seismic intensity at location P2 (estimated ground surface seismic intensity). Next, the seismic intensity estimation unit 22 obtains vibration characteristic information indicating the vibration characteristics of the bridge located on the ground surface at location P2 from the vibration characteristic DB 16. Based on the ground surface seismic intensity at location P2 and the vibration characteristics of the bridge (e.g., natural period), the seismic intensity estimation unit 22 estimates the seismic intensity at the location of the vehicle on the bridge ("estimated seismic intensity on the bridge" in Figure 4). The output unit 24 outputs the estimated seismic intensity information indicating the estimated seismic intensity on the bridge as information indicating the estimated seismic intensity at the vehicle's location.

[0035] Even when the vehicle is on an elevated structure built on the ground surface at position P3, the seismic intensity estimation unit 22 estimates the seismic intensity at the vehicle's position on the elevated structure ("Estimated seismic intensity on the elevated structure" in Figure 4), just as when the vehicle is on a bridge. The output unit 24 outputs the estimated seismic intensity information showing the estimated seismic intensity on the elevated structure as information showing the estimated seismic intensity at the vehicle's position.

[0036] According to the embodiment described above, when a vehicle is located on a structure, the seismic intensity at the vehicle's position is estimated by considering the vibration characteristics of the structure, thus enabling accurate estimation of the seismic intensity at the vehicle's position.

[0037] When a vehicle is traveling on an elevated structure or bridge, the vibrations are amplified by the vibration characteristics of the structure, which can cause the vehicle to experience stronger vibrations than it would at ground level. According to this embodiment, the seismic intensity on the vehicle can be estimated more accurately, allowing for the output of more accurate information to the vehicle and the vehicle operation system.

[0038] The seismic intensity estimation unit 22 may estimate the seismic intensity using machine learning such as deep learning. For example, a learning model may be constructed that has learned earthquake information, ground characteristics of each area, vibration characteristics of each structure, and seismic intensity on each structure, and the seismic intensity estimation unit 22 may use this learning model to estimate the seismic intensity.

[0039] The seismic intensity estimation device 10 includes, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), a DSP (Digital Signal Processor), other programmable logic devices, or electronic circuits.

[0040] The functions of the seismic intensity estimation device 10 are realized through the cooperation of hardware and software resources. For example, each function is realized by the CPU reading and executing a program stored in a memory device. The program is stored in the memory device via a recording medium such as a CD or DVD, or via a communication path such as a network. As another example, the functions of the seismic intensity estimation device 10 may be realized by hardware resources such as electronic circuits. [Explanation of Symbols]

[0041] 10 Seismic intensity estimation device, 12 Ground characteristics DB, 14 Structure location DB, 16 Seismic intensity characteristics DB, 18 Receiving unit, 20 Vehicle location management unit, 22 Seismic intensity estimation unit, 24 Output unit.

Claims

1. A depth estimation device for estimating seismic intensity at the position of a vehicle, A receiving unit that receives earthquake information indicating the occurrence and magnitude of an earthquake, A vehicle location management unit that acquires information indicating the current location of the vehicle, An earthquake intensity estimation unit estimates the ground intensity at the vehicle's current location based on the magnitude of the earthquake indicated by the earthquake information and the ground characteristics at the vehicle's current location. Equipped with, The seismic intensity estimation unit is, The system refers to a structural location database that stores structural location information indicating the location of a structure, and determines whether the vehicle is currently on the structure. If it is determined that the vehicle is currently on a structure, the vibration characteristics of the structure are acquired, and the seismic intensity at the vehicle's current location is estimated based on the seismic intensity at the ground surface and the acquired vibration characteristics. If it is determined that the vehicle is not currently on a structure, the seismic intensity at the ground surface is estimated as the seismic intensity at the vehicle's current location. A seismic intensity estimation device characterized by the following features.

2. In the seismic intensity estimation device according to claim 1, The seismic intensity estimation unit estimates seismic intensity using machine learning. A seismic intensity estimation device characterized by the following features.

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