JP7399069B2 - Flood control facility monitoring device, flood control facility monitoring method, and flood control facility monitoring program - Google Patents

Description

The present disclosure relates to monitoring of flood control facilities such as seawalls.

A technique described in Patent Document 1 is known as an inspection method for inspecting the state of a slope and recording the state and position of the deformation. In the slope inspection method disclosed in Patent Document 1, three-dimensional measurement data of the slope is created by continuously photographing the slope from a vehicle using multiple cameras with different focal lengths, and the deformation of the slope is detected. Determine condition and location. With this technology, even when inspecting a vast river revetment, it is possible to collect the data necessary for inspection by driving a vehicle over the top of the river revetment, making it possible to directly inspect the revetment visually. Comparative labor savings are possible.

Patent No. 6498488

The technology described in Patent Document 1 enables labor savings compared to conventional methods. However, with the technique described in Patent Document 1, the data collection time increases in proportion to the size of a water area targeted for flood control, such as a river. For this reason, the technique described in Patent Document 1 has a problem in that it takes time to detect deformation of flood control facilities when the water area to be flood controlled is large.

The main purpose of the present disclosure is to solve the above problems. Specifically, the main purpose of the present disclosure is to enable early detection of deformation of flood control facilities even if the water area targeted for flood control is large.

The flood control facility monitoring device according to the present disclosure is
an image acquisition unit that acquires a satellite photographed image obtained by photographing a flood control facility and a water area targeted for flood control of the flood control facility by an artificial satellite;
and an estimation unit that analyzes changes over time in at least one of the flood control facility and the water area using reflection spectrum characteristics in the satellite image, and estimates deformation of the flood control facility.

According to the present disclosure, even if the water area targeted for flood control is large, deformation of flood control facilities can be detected early.

1 is a diagram showing an example of a functional configuration of a flood control facility monitoring device according to Embodiment 1. FIG. 1 is a diagram showing an example of the hardware configuration of a flood control facility monitoring device according to Embodiment 1. FIG. 2 is a flowchart illustrating an example of a processing flow of the seawall monitoring method according to the first embodiment. FIG. 3 is a diagram showing an example of an optical satellite image before vegetation overgrowth and an optical satellite image after vegetation overgrowth according to Embodiment 1; FIG. 3 is a diagram illustrating an example of an optical satellite image before the occurrence of omission/collapse and an optical satellite image after occurrence of omission/collapse according to the first embodiment. FIG. 2 is a diagram showing an example of an optical satellite image before water rise and an optical satellite image after water rise according to Embodiment 1. FIG. FIG. 7 is a diagram showing an example of a functional configuration of a flood control facility monitoring device according to a second embodiment. 7 is a flowchart illustrating an example of a processing flow of a seawall monitoring method according to a second embodiment.

Hereinafter, embodiments will be described using figures. In the following description of the embodiments and drawings, the same reference numerals indicate the same or corresponding parts.

Embodiment 1.
***overview***
In this embodiment, a flood control facility monitoring device that monitors flood control facilities will be described. Flood control facilities are facilities used for flood control. Flood control is a project to prevent flood damage and/or landslides. Flood damage includes floods, storm surges, etc. Landslides include landslides, debris flows, steep slope collapses, etc. Specifically, flood control facilities include sea walls, embankments, dams, spillways, and retarding ponds.
In the following, explanation will be given using a seawall as an example of a flood control facility and a river as an example of a water area targeted for flood control. A sea wall, which is a flood control facility, is in contact with a river, which is a water area targeted for flood control.

As mentioned above, in the technique of Patent Document 1, it takes a long time to collect data if the river is long. For this reason, the technique of Patent Document 1 has the problem that if the river is long, it is not possible to efficiently monitor the seawall, and it takes time to detect the deformation of the seawall. Furthermore, the technique disclosed in Patent Document 1 has a problem in that inspection cannot be performed when the visibility between the road on which the vehicle is traveling and the seawall is obstructed by thick vegetation or the like.

In this embodiment, optical satellite images are used for wide-area seawall monitoring. When using optical satellite images, it is possible to observe the ground over a very wide range of several tens of ^km2 to several hundred ^km2 at a time, and it is also possible to easily photograph a wide area of seawalls. On the other hand, compared to photography from the ground, photography from an artificial satellite generally has inferior ground resolution, and as described in Patent Document 1, it is difficult to directly visually detect and record deformations from images. may occur.

Therefore, in this embodiment, a secondary phenomenon caused by the deformation of the seawall is detected using time-series satellite images and reflection spectrum information on the satellite image, and the position and state of the deformation of the seawall are estimated.
If a point on a seawall on past optical satellite images shows the reflection spectrum characteristics of vegetation, it is possible that vegetation has grown from the ground beneath the seawall due to cracks or openings in the seawall, causing deformation. Record as. In addition, when focusing on low-water revetments in particular, when a collapse or omission occurs in the revetment, water inundates from the river at the relevant location and exhibits water absorption spectral characteristics. Utilizing this characteristic, if a point on a seawall exhibits water absorption spectrum characteristics on past optical satellite images, it is recorded as having collapsed or fallen through.
***Explanation of configuration***
FIG. 1 shows an example of the functional configuration of a flood control facility monitoring device 100 according to the present embodiment.
Moreover, FIG. 2 shows an example of the hardware configuration of the flood control facility monitoring device 100 according to the present embodiment.
The operation procedure of the flood control facility monitoring device 100 corresponds to a flood control facility monitoring method. Further, a program that realizes the operation of the flood control facility monitoring device 100 corresponds to a flood control facility monitoring program.

Below, first, an example of the hardware configuration of the flood control facility monitoring device 100 will be described with reference to FIG.

Flood control facility monitoring device 100 according to this embodiment is a computer.
The flood control facility monitoring device 100 includes a processor 901, a main storage device 902, an auxiliary storage device 903, a communication device 904, and a display device 905 as hardware.
The flood control facility monitoring device 100 also includes an image acquisition section 101, a position adjustment section 102, an estimation section 103, and an estimation result output section 108 as functional configurations.
The auxiliary storage device 903 stores programs that implement the functions of the image acquisition section 101, position adjustment section 102, estimation section 103, and estimation result output section 108.
These programs are loaded from the auxiliary storage device 903 to the main storage device 902. The processor 901 executes these programs to operate the image acquisition unit 101, position adjustment unit 102, estimation unit 103, and estimation result output unit 108, which will be described later.
FIG. 2 schematically shows a state in which the processor 901 is executing a program that implements the functions of the image acquisition unit 101, position adjustment unit 102, estimation unit 103, and estimation result output unit 108.
The communication device 904 is used for communication with an external device outside the flood control facility monitoring device 100.
The display device 905 displays various information to the user of the flood control facility monitoring device 100.

Next, an example of the functional configuration of the flood control facility monitoring device 100 will be described with reference to FIG. 1.

The image acquisition unit 101 acquires optical satellite images of a river, which is a water area targeted for flood control, and a seawall, which is a flood control facility. The image acquisition unit 101 acquires an optical satellite image from an artificial satellite or from a terrestrial satellite communication system via the communication device 904, for example. Optical satellite images are satellite images obtained by simultaneously photographing rivers and seawalls in multiple wavelength bands using artificial satellites. The image acquisition unit 101 acquires a plurality of optical satellite images taken at a plurality of times.
Note that the processing performed by the image acquisition unit 101 corresponds to an image acquisition step and an image acquisition process.

The position adjustment unit 102 adjusts the positions of the plurality of optical satellite images acquired by the image acquisition unit 101. That is, the position adjustment unit 102 performs position adjustment between optical satellite images. Note that if the image acquisition unit 101 can acquire a plurality of optical satellite images whose alignment has been completed, the position adjustment unit 102 can be omitted.

The estimation unit 103 analyzes changes over time in at least one of the seawall and the river using reflection spectrum characteristics in a plurality of optical satellite images, and estimates deformation of the seawall. Deformation of the seawall is, for example, cracks or openings in the seawall, or omissions or collapse of the seawall.
The processing performed by the estimation unit 103 corresponds to an estimation step and an estimation process.

For example, the estimating unit 103 analyzes at least one of a change in the shape of the seawall over time and a change in vegetation on the seawall over time as the change in the seawall over time. Further, the estimating unit 103 estimates the deformation of the seawall when the shape of the seawall is changing in the vicinity of the area where the seawall contacts the river as a result of analyzing the change over time in the shape of the seawall. Further, the estimating unit 103 estimates deformation of the seawall when the range of vegetation is increasing in the vicinity of the area where the seawall contacts the river as a result of analyzing changes in vegetation over time. Further, the estimating unit 103 estimates deformation of the bank if the range of the river is increasing as a result of analyzing changes in the river over time.

The estimation unit 103 includes an artificial object extraction unit 104, a vegetation extraction unit 105, a water area extraction unit 106, and a deformation estimation unit 107 as internal components.

The artifact extraction unit 104 extracts an image area of the seawall from the optical satellite image using the reflection spectrum characteristics of the artifact. Note that, hereinafter, extracting the image area of the seawall is also simply referred to as extracting the seawall.

The vegetation extraction unit 105 extracts an image area of vegetation from the optical satellite image using reflection spectrum characteristics of vegetation. Note that, hereinafter, extracting an image area of vegetation is also simply referred to as extracting vegetation.

The water area extraction unit 106 extracts an image area of a river from the optical satellite image using the reflection spectrum characteristics of the water surface. Note that, hereinafter, extracting an image area of a river is also simply referred to as extracting a river.

The deformation estimating unit 107 uses the image region of the seawall extracted by the artifact extracting unit 104 to analyze changes over time in the shape of the seawall. Further, the deformation estimating unit 107 analyzes changes in vegetation over time using the image area of the vegetation extracted by the vegetation extracting unit 105. Further, the deformation estimating unit 107 analyzes changes in the river over time using the image region of the river extracted by the water area extracting unit 106. Then, the deformation estimation unit 107 estimates the deformation of the seawall based on the analysis results.

The estimation result output unit 108 outputs to the display device 905 the type and position of the deformation of the seawall estimated by the deformation estimation unit 107 (cracks, open joints, omissions, collapses, etc.). The estimation result output unit 108 outputs coordinate values as the position of the deformation. Furthermore, the estimation result output unit 108 may output the optical satellite image in which the deformation is estimated, and may mark a position on the output optical satellite image where the deformation is estimated to have occurred.
Furthermore, instead of outputting to the display device 905 or in addition to outputting to the display device 905, the estimation result output unit 108 may output the type and position of the deformation of the seawall to, for example, an external user terminal device. good.

***Operation explanation***
FIG. 3 shows a processing flow of a seawall monitoring method by the flood control facility monitoring device 100 according to the present embodiment.

First, the image acquisition unit 101 acquires an optical satellite image (step ST1).
In other words, the image acquisition unit 101 acquires a series of optical satellite images (time-series optical satellite images) of the river and seawall to be monitored at a plurality of times. These optical satellite images each include the same point and satisfy the conditions for simultaneous imaging in multiple wavelength bands.
The image acquisition unit 101 stores the acquired optical satellite image in, for example, the auxiliary storage device 903.

Next, the position adjustment unit 102 performs position alignment between the time-series optical satellite images acquired in step ST1 (step ST2).
For example, the position adjustment unit 102 can perform position alignment by determining the amount of shift between images from the coordinates of the maximum value of the cross-correlation function determined from a plurality of optical satellite images. Alternatively, the position adjustment unit 102 may perform position adjustment by projecting each optical satellite image onto a map.
Note that if alignment has already been performed in the optical satellite image acquired in step ST1, step ST2 is not necessary.

Next, the artifact extraction unit 104 of the estimation unit 103 extracts a seawall from each optical satellite image (step ST3).
That is, the artifact extraction unit 104 extracts the image area of the seawall from the reflection spectrum characteristics of each point corresponding to each pixel obtained from the optical satellite image.
Further, the vegetation extraction unit 105 of the estimation unit 103 extracts vegetation from each optical satellite image (step ST4).
That is, the vegetation extraction unit 105 extracts the image area of vegetation from the reflection spectrum characteristics of each point corresponding to each pixel obtained from the optical satellite image.
Furthermore, the water area extraction unit 106 of the estimation unit 103 extracts rivers from each optical satellite image (step ST5).
That is, the water area extraction unit 106 extracts the image area of the river from the reflection spectrum characteristic of each point corresponding to each pixel obtained from the optical satellite image.
Details of steps S3 to ST5 will be explained below.

The artifact extraction unit 104 uses an artifact index that is used for extracting features with uniform visible light reflection spectrum characteristics, such as concrete and asphalt, to extract an image area of the artifact. An example of a method for calculating the artifact index is shown in equation (1).

A feature with more uniform reflection spectrum characteristics for visible light exhibits a NHFD (Non-Homogeneous Feature Difference) value closer to 0. By using artifact indicators, points whose surfaces are covered with concrete can be detected from optical satellite images, and if the point is in contact with a river, it can be identified as a concrete revetment.
If cracks or joints open up in a seawall whose surface is covered with concrete due to expansion and contraction due to ground fluctuations or temperature changes, vegetation will grow from the ground below the seawall, causing the joints that have formed in the seawall to grow. A phenomenon in which vegetation grows thickly over a wider area compared to the opening can be observed.

In order to extract the image area of the vegetation growing on the seawall from the optical satellite image, we use an index that extracts the vegetation using the reflection spectrum characteristics unique to the vegetation. A calculation formula for a normalized vegetation index NDVI (Normalized Difference Vegetation Index), which is an example of an index for extracting vegetation, is shown in Equation (2).

Vegetation has a high reflectance for near-infrared light, but a low reflectance for red light. Therefore, vegetation exhibits a high NDVI value, and it is possible to detect an image area of vegetation from the NDVI value.

Furthermore, when a revetment in contact with the water surface of a river falls off or collapses, water may flood into the location where the revetment existed before the collapse. Therefore, the water area extraction unit 106 detects the leakage or collapse of the seawall by detecting the inundation of the seawall on the optical satellite image.
Similar to artificial objects and vegetation, the location of river bodies of water can be determined using an index that extracts water areas based on reflection spectrum characteristics in optical satellite images. Equation (3) shows the calculation of the standardized water index, which is an example of an index for extracting water bodies.

Water exhibits a relatively high transmittance for light with a wavelength of 400 nm to 580 nm (blue to green), and conversely exhibits a very high absorbance for light with a wavelength of approximately 1000 nm to 3000 nm (short wavelength infrared). Therefore, water exhibits a high NDWI (Normalized Difference Water Index) value, and river bodies of water can be easily detected from optical satellite images.

Next, based on the image area of the seawall, the image area of vegetation, and the image area of the water area of the river obtained by the above method, the deformation estimation unit 107 determines the area of the seawall, vegetation, and water area of the river in the time-series optical satellite images. Each change over time is analyzed (step ST6).

If the position extracted as a seawall on an optical satellite image taken at a certain point shows the characteristics of vegetation on an optical satellite image taken after that point (step ST7), the deformation estimation unit 107 The process of step ST8 is performed.
In step ST8, the deformation estimating unit 107 detects cracks or joints in the seawall at the corresponding position if the position where the seawall has changed to vegetation is in contact with a river on the optical satellite image or is within a specified range from the river. It is estimated that a crack or joint opening has occurred, and the possibility that a crack or joint opening has occurred is recorded in the main storage device 902 or the auxiliary storage device 903.
Furthermore, if the coordinate values of the relevant position can be acquired, the deformation estimating unit 107 also records the coordinate values of the relevant position in the main storage device 902 or the auxiliary storage device 903. The deformation estimating unit 107 can obtain, for example, coordinate values of a point where a crack or a joint opening is estimated to have occurred from latitude and longitude information obtained when taking an optical satellite image.
In this way, the deformation estimating unit 107 estimates that cracks or joint openings have occurred in the seawall when the range of vegetation has increased in the area adjacent to the river or in the vicinity of the river.

On the other hand, if the position extracted as a seawall on an optical satellite image taken at a certain point shows the characteristics of a water area of a river on an optical satellite image taken after that point (step ST9), The estimation unit 107 performs the process of step ST10.
In step S10, the deformation estimating unit 107 determines whether the position where the sea wall has changed from the sea wall to the water area of the river is in contact with the river on the optical satellite image, or if it is within a specified range from the river. Alternatively, it is estimated that a collapse has occurred, and the possibility that the collapse or collapse has occurred is recorded in the main storage device 902 or the auxiliary storage device 903.
Furthermore, if the coordinate values of the relevant position can be acquired, the deformation estimating unit 107 also records the coordinate values of the relevant position in the main storage device 902 or the auxiliary storage device 903. The deformation estimating unit 107 can obtain the coordinate values of a point where a dropout or collapse is estimated to have occurred, for example, from latitude and longitude information obtained when taking an optical satellite image.
In this way, the deformation estimating unit 107 estimates that a break or collapse has occurred in the seawall when flooding has occurred in an area adjacent to a river or in the vicinity of a river.

Finally, the estimation result output unit 108 outputs the estimation result of the deformation estimation unit 107 (step ST11).
That is, the estimation result output unit 108 outputs the items recorded in the main storage device 902 or the auxiliary storage device 903 in step ST8 or step ST10 to the display device 905.

FIG. 4 shows a specific example of step ST7 and step ST8 in FIG.
(a) of FIG. 4 shows an optical satellite image taken on September 1, 2020. FIG. 4(b) shows an optical satellite image taken on October 1, 2020.
The optical satellite images shown in FIGS. 4A and 4B are images obtained by photographing the river 200 and the seawall 300 from above (artificial satellite).
As shown in (a) of FIG. 4, as of September 1, 2020, there is no vegetation 400 on the seawall 300. However, on October 1, 2020, one month later, as shown in FIG. 4(b), vegetation 400 exists.
The deformation estimating unit 107 detects that the position of the seawall 300 in the optical satellite image of FIG. 4(a) has changed to vegetation 400 in the optical satellite image of FIG. 4(b) (step ST7), it is estimated that a crack or a joint opening has occurred at the position (Step ST8).

FIG. 5 shows a specific example of step ST9 and step ST10 in FIG.
(a) of FIG. 5 shows an optical satellite image taken on September 1, 2020. FIG. 5(b) shows an optical satellite image taken on October 1, 2020.
The optical satellite image in FIG. 5(a) is the same as FIG. 4(a).
As shown in FIG. 5(a), as of September 1, 2020, there is no flooded area 500 in the seawall 300. However, one month later, on October 1, 2020, there is a flooded location 500, as shown in FIG. 5(b).
The deformation estimating unit 107 determines that the position of the seawall 300 in the optical satellite image in FIG. 5(a) has changed to the water area of a river at the flooded location 500 in the optical satellite image in FIG. 5(b). is detected (step ST9), and it is estimated that a dropout or collapse has occurred at the position (step ST10).

Although not included in the flowchart of FIG. 3, the deformation estimating unit 107 analyzes a plurality of optical satellite images and estimates river water increase (river inflow into the revetment) as a deformation of the revetment. You may. In this case, the deformation estimating unit 107 determines that the position extracted as a seawall on the optical satellite image taken at a certain point in time indicates the characteristics of the water area of the river on the optical satellite image taken after that point. (Step ST9), if the boundary line between the bank and the river has moved toward the bank, it is estimated that the water in the river is rising.

FIG. 6 shows an example in which the deformation estimating unit 107 estimates a river water increase.
(a) of FIG. 6 shows an optical satellite image taken on September 1, 2020. FIG. 6(b) shows an optical satellite image taken on October 1, 2020.
The optical satellite image in FIG. 6(a) is the same as FIG. 4(a).
As shown in (a) of FIG. 6, as of September 1, 2020, the boundary line between the seawall 300 and the river 200 is along the end surface of the seawall 300. However, on October 1, 2020, one month later, the boundary line between the seawall 300 and the river 200 has moved toward the seawall 300, as shown in FIG. 6(b). In FIG. 6(b), the broken line represents the boundary line between the seawall 300 and the river 200 as of September 1, 2020. In addition, the solid line represents the boundary line between the seawall 300 and the river 200 as of October 1, 2020.
The deformation estimating unit 107 detects that the position of the seawall 300 in the optical satellite image of FIG. 6(a) has changed to the water area of a river in the optical satellite image of FIG. 6(b). In step ST9), it is further detected that the boundary line is moving toward the seawall 300, and it is estimated that the river is rising.

***Explanation of effects of embodiment***
As described above, according to the present embodiment, even if the water area targeted for flood control is large, deformation of flood control facilities can be detected early.
In other words, in this embodiment, a vast area of water can be monitored at once by using satellite images. Therefore, in this embodiment, deformation can be efficiently monitored even if the water area is large, and deformation of the flood control facility can be detected at an early stage.
Furthermore, according to the present embodiment, it is possible to estimate the occurrence of a specific type of deformation and its position.
Further, in this embodiment, since satellite images are used, there is no problem that deformation of the seawall cannot be confirmed because the view between the road on which the vehicle is traveling and the seawall is obstructed by thick vegetation.

Embodiment 2.
In this embodiment, a flood control facility monitoring device 100 that uses map information will be described.
In this embodiment, differences from Embodiment 1 will be mainly explained.
Note that matters not described below are the same as in the first embodiment.

***Explanation of configuration***
FIG. 7 shows an example of the functional configuration of the flood control facility monitoring device 100 according to the present embodiment.
Compared to FIG. 1, a map information acquisition unit 109 is added in FIG.
The map information acquisition unit 109 acquires map information including the positions of rivers and seawalls from, for example, an external device via the communication device 904.
The map information acquisition unit 109 is also realized by a program, similar to the image acquisition unit 101 and the like.

In this embodiment, the image acquisition unit 101 acquires only optical satellite images at a specific time (current time). In the first embodiment, a plurality of optical satellite images at a plurality of times are acquired, but in this embodiment, by utilizing map information, the image acquisition unit 101 only needs to acquire one optical satellite image.
Further, in the present embodiment, the position adjustment unit 102 uses the map information acquired by the map information acquisition unit 109 to align the optical satellite images.
Further, in this embodiment, the artifact extraction unit 104 extracts a seawall from the optical satellite image using the reflection spectrum characteristics of the artifact and map information.
Furthermore, in the present embodiment, the vegetation extraction unit 105 extracts vegetation from the optical satellite image using the reflection spectrum characteristics of the vegetation and map information.
Furthermore, in this embodiment, the water area extraction unit 106 extracts the water area of a river from the optical satellite image using the reflection spectrum characteristics of the water surface and map information.
Furthermore, in this embodiment, the deformation estimating unit 107 uses map information to identify the coordinates of the position where the deformation has occurred.
The estimation result output unit 108 is the same as that shown in FIG. 1, so a description thereof will be omitted.

***Operation explanation***
Next, with reference to FIG. 8, a processing flow of a seawall monitoring method by the flood control facility monitoring device 100 according to the present embodiment will be described.

First, the image acquisition unit 101 acquires an optical satellite image (step ST21).
As described above, the image acquisition unit 101 acquires the optical satellite image at the current time.
The image acquisition unit 101 stores the acquired optical satellite image in, for example, the auxiliary storage device 903.

Next, the map information acquisition unit 109 acquires map information including the positions of the river and the seawall (step ST31).
For example, the map information acquisition unit 109 acquires map information from an external map server device.
The map information acquisition unit 109 stores the acquired map information in, for example, the auxiliary storage device 903.

Next, the position adjustment unit 102 projects the optical satellite image acquired in step ST21 onto the map information acquired in step S31 (step ST32).
By projecting the optical satellite image onto map information, the positions (coordinate values) of the bank and river on the optical satellite image can be determined.

Steps ST3 to ST5 are the same as those shown in FIG. 3, so detailed explanation will be omitted.
In addition, in FIG. 8, it is assumed that steps ST4 and ST5 are performed using the optical satellite image after the map projection process in step ST32, but steps ST4 and ST5 are performed using the optical satellite image before the map projection process. It may also be done using

When the position indicated as a seawall on the map information shows the characteristics of vegetation on the optical satellite image after map projection processing (step ST27), the deformation estimating unit 107 performs the process of step ST28.
In step ST28, the deformation estimating unit 107 determines whether the seawall has cracks or It is estimated that a joint opening has occurred, and the possibility that a crack or a joint opening has occurred is recorded in the main storage device 902 or the auxiliary storage device 903.
Further, the deformation estimation unit 107 also records the coordinate values of the corresponding position in the main storage device 902 or the auxiliary storage device 903. Since the optical satellite image is projected onto the map information, the deformation estimating unit 107 can obtain the coordinate values of the point where the crack or joint opening is estimated to have occurred from the map information.

On the other hand, if the position indicated as a seawall on the map information shows the characteristics of the water area of the river on the optical satellite image after map projection processing (step ST29), the deformation estimation unit 107 performs step ST30. Perform processing.
In step S30, the deformation estimating unit 107 determines whether the position where the sea wall has changed from the sea wall to the water area of the river is in contact with the river on the optical satellite image, or if it is within a specified range from the river, the change estimating unit 107 detects that the sea wall has passed through the sea wall at the corresponding position. Alternatively, it is estimated that a collapse has occurred, and the possibility that the collapse or collapse has occurred is recorded in the main storage device 902 or the auxiliary storage device 903.
Further, the deformation estimation unit 107 also records the coordinate values of the corresponding position in the main storage device 902 or the auxiliary storage device 903. As described above, since the optical satellite image is projected onto the map information, the deformation estimating unit 107 can obtain the coordinate values of the point where the dropout or collapse is estimated to have occurred from the map information. be.

Since step ST11 is similar to that shown in FIG. 3, detailed explanation will be omitted.

Also in this embodiment, the flood control facility monitoring device 100 may estimate the increase in water in the river as described using FIG. 6 as the deformation of the bank.

***Explanation of effects of embodiment***
According to this embodiment, there is no need to acquire and record multiple optical satellite images, so computer resources can be saved.

Although Embodiments 1 and 2 have been described above, these two embodiments may be implemented in combination.
Alternatively, one of these two embodiments may be partially implemented.
Alternatively, these two embodiments may be partially combined.
Further, the configurations and procedures described in these two embodiments may be changed as necessary.

***Supplementary explanation of hardware configuration***
Finally, a supplementary explanation of the hardware configuration of the flood control facility monitoring device 100 will be given.
A processor 901 shown in FIG. 2 is an IC (Integrated Circuit) that performs processing.
The processor 901 is a CPU (Central Processing Unit), a DSP (Digital Signal Processor), or the like.
The main storage device 902 shown in FIG. 2 is a RAM (Random Access Memory).
The auxiliary storage device 903 shown in FIG. 2 is a ROM (Read Only Memory), a flash memory, an HDD (Hard Disk Drive), or the like.
The communication device 904 shown in FIG. 2 is an electronic circuit that executes data communication processing.
The communication device 904 is, for example, a communication chip or NIC (Network Interface Card).
The display device 905 is, for example, an LCD (Liquid Crystal Display).

The auxiliary storage device 903 also stores an OS (Operating System).
At least a portion of the OS is executed by the processor 901.
The processor 901 executes programs that implement the functions of the image acquisition unit 101, position adjustment unit 102, estimation unit 103, estimation result output unit 108, and map information acquisition unit 109 while executing at least a part of the OS.
When the processor 901 executes the OS, task management, memory management, file management, communication control, etc. are performed.
Further, at least one of information, data, signal values, and variable values indicating the processing results of the image acquisition unit 101, position adjustment unit 102, estimation unit 103, estimation result output unit 108, and map information acquisition unit 109 is stored in the main memory. The information is stored in at least one of the device 902, the auxiliary storage device 903, a register in the processor 901, and a cache memory.
In addition, programs that realize the functions of the image acquisition unit 101, position adjustment unit 102, estimation unit 103, estimation result output unit 108, and map information acquisition unit 109 include magnetic disks, flexible disks, optical disks, compact discs, Blu-ray (registered trademark) ) may be stored in a portable recording medium such as a disk or DVD. Then, a portable recording medium storing a program that implements the functions of the image acquisition section 101, position adjustment section 102, estimation section 103, estimation result output section 108, and map information acquisition section 109 may be distributed.

In addition, the "units" in the image acquisition section 101, position adjustment section 102, estimation section 103, estimation result output section 108, and map information acquisition section 109 are replaced with "circuit" or "process" or "procedure" or "processing."It's okay.
Furthermore, the flood control facility monitoring device 100 may be realized by a processing circuit. The processing circuit is, for example, a logic IC (Integrated Circuit), a GA (Gate Array), an ASIC (Application Specific Integrated Circuit), or an FPGA (Field-Programmable Gate Array). ay).
In this case, the image acquisition section 101, the position adjustment section 102, the estimation section 103, the estimation result output section 108, and the map information acquisition section 109 are each implemented as part of a processing circuit.

100 Flood control facility monitoring device, 101 Image acquisition unit, 102 Position adjustment unit, 103 Estimation unit, 104 Artifact extraction unit, 105 Vegetation extraction unit, 106 Water area extraction unit, 107 Deformation estimation unit, 108 Estimation result output unit, 109 Map Information acquisition unit, 200 river, 300 bank protection, 400 vegetation, 500 flooded area, 901 processor, 902 main storage device, 903 auxiliary storage device, 904 communication device, 905 display device.

Claims (8)

an image acquisition unit that acquires a satellite photographed image obtained by photographing a water area to be subject to flood control and a flood control facility adjacent to the water area using an artificial satellite;
The changes in vegetation over time at the flood control facility were analyzed using the reflection spectrum characteristics in the satellite image, and as a result of analyzing the changes over time in the vegetation, the extent of the vegetation in the vicinity of the area where the flood control facility touches the water area was determined. a flood control facility monitoring device , comprising: an estimation unit that estimates deformation of the flood control facility when the amount of water is increasing ; The estimation unit is
If the shape of the flood control facility is changing in the vicinity of the area where the flood control facility touches the water body, as a result of analyzing the change in the shape of the flood control facility over time, The flood control facility monitoring device according to claim 1 , which estimates deformation of the flood control facility. The estimation unit is
The flood control facility monitoring device according to claim 1, wherein the flood control facility monitoring device analyzes changes over time in the water area , and estimates deformation of the flood control facility when the range of the water area increases as a result of analyzing the changes over time in the water area. . The estimation unit is
The flood control facility monitoring device according to claim 1, which acquires coordinate values of the position where the deformation is estimated. The image acquisition unit includes:
acquiring a plurality of satellite images of the flood control facility and the water body taken by an artificial satellite at a plurality of times;
The estimation unit is
The flood control facility monitoring device according to claim 1, wherein changes over time in vegetation at the flood control facility are analyzed using reflection spectrum characteristics in the plurality of satellite images. The flood control facility monitoring device further includes:
comprising a map information acquisition unit that acquires map information including the flood control facility and the water area;
The estimation unit is
2. The flood control facility monitoring device according to claim 1, wherein changes over time in vegetation at the flood control facility are analyzed using the reflection spectrum characteristics in the satellite image and the map information. an image acquisition step in which the computer acquires a satellite photographed image of a water area to be subject to flood control and a flood control facility in contact with the water area, taken by an artificial satellite;
The computer analyzes changes in vegetation over time at the flood control facility using the reflection spectrum characteristics in the satellite image, and as a result of analyzing the changes over time in the vegetation, the computer analyzes changes over time in the vegetation at the flood control facility using reflectance spectrum characteristics in the satellite image, and as a result of analyzing the changes over time in the vegetation, A flood control facility monitoring method comprising: an estimation step of estimating deformation of the flood control facility when the range of the vegetation is increasing . an image acquisition process of acquiring a satellite photographed image obtained by photographing a water area to be subject to flood control and a flood control facility adjacent to the water area using an artificial satellite;
The changes in vegetation over time at the flood control facility were analyzed using the reflection spectrum characteristics in the satellite image, and as a result of analyzing the changes over time in the vegetation, the extent of the vegetation in the vicinity of the area where the flood control facility touches the water area was determined. A flood control facility monitoring program that causes a computer to execute an estimation process of estimating a deformation of the flood control facility when the flood control facility is increasing .

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