Information processing apparatus, information processing method, and program

Abstract

To accurately determine the occurrence state of defoliation of plants.SOLUTION: An information processing apparatus 1 includes a control unit, a communication unit, and a memory unit, wherein the control unit performs operations including: obtaining time series data of backscatter coefficients based on data measured by synthetic aperture radar of a satellite 3 transmitting radio waves in a geographic area; determining an occurrence state of defoliation of a plant based on the time series data; and outputting information regarding the occurrence state.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an information processing device, an information processing method, and a program. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a system is known that detects the state of leaf fall on trees using an optical sensor on an artificial satellite (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2022 / 080418 Summary of the Invention [Problem to be solved by the invention]

[0004] In rainy tropical regions where rubber plantations are located, there are many clouds, and it is difficult to evaluate the vegetation condition in cloudy areas using optical sensors on artificial satellites. Therefore, when trying to evaluate the vegetation condition using optical sensors, it is necessary to increase the observation frequency. However, when optical sensor data is acquired frequently, the spatial resolution of the obtained image becomes low. The spatial resolution of the above background technology is 500m.

[0005] An object of the present disclosure, made in consideration of the above circumstances, is to accurately determine the state of defoliation of plants. [Means for solving the problem]

[0006] [1] An information processing device according to an embodiment of the present disclosure, An information processing device including a control unit, a communication unit, and a storage unit, the control unit comprising: Obtaining time series data of backscattering coefficient based on data measured by a synthetic aperture radar of a satellite that transmits radio waves to a geographical area; determining a state of defoliation of plants based on the time-series data; and outputting information regarding the occurrence status; The operation includes: With this configuration, the state of leaf fall can be determined with high accuracy, regardless of the weather or other factors in the geographical area being observed.

[0007] [2] An information processing device according to an embodiment of the present disclosure, In the information processing device according to the above item [1], The operation preferably includes storing position information of the geographical area in association with the time-series data in the storage unit, and outputting position information of the location where leaf fall has occurred to a user terminal. This configuration makes it possible to identify the area where leaf fall has occurred, making it easier to deal with plant diseases, etc.

[0008] [3] An information processing device according to an embodiment of the present disclosure, In the information processing device according to the above item [1] or [2], Preferably, the defoliation status is determined using time series data for one or more other geographic regions. This configuration can improve the accuracy of determining the occurrence of leaf fall.

[0009] [4] An information processing device according to an embodiment of the present disclosure, In the information processing device according to any one of the above items [1] to [3], The defoliation status is preferably determined using past time series data for the geographical area. This configuration can improve the accuracy of determining the occurrence of leaf fall.

[0010] [5] An information processing device according to an embodiment of the present disclosure, In the information processing device according to any one of the above items [1] to [4], The occurrence of fallen leaves is preferably determined using a VH polarized wave, which indicates vertical wave transmission and horizontal wave reception, or an HV polarized wave, which indicates horizontal wave transmission and vertical wave reception. This configuration can improve the accuracy of determining the occurrence of defoliation, because it is known that for objects with large unevenness such as plants, the direction of wave reflection is disturbed, making the VH and HV signals relatively strong.

[0011] [6] An information processing device according to an embodiment of the present disclosure, In the information processing device according to any one of the above items [1] to [5], Preferably, said operations include correcting said time series data according to the topography or slope of said geographical area. This configuration can improve the accuracy of determining the occurrence of leaf fall.

[0012] [7] An information processing method according to an embodiment of the present disclosure, An information processing method by an information processing device including a control unit, a communication unit, and a storage unit, Obtaining time series data of backscattering coefficient based on data measured by a synthetic aperture radar of a satellite that transmits radio waves to a geographical area; determining a state of defoliation of plants based on the time-series data; and outputting information regarding the occurrence status; Includes. With this configuration, the state of leaf fall can be determined with high accuracy, regardless of the weather or other factors in the geographical area being observed.

[0013] [8] A program according to an embodiment of the present disclosure, A program for causing a computer to function as the information processing device described in [1] above. With this configuration, the state of leaf fall can be determined with high accuracy, regardless of the weather or other factors in the geographical area being observed. Effect of the Invention

[0014] According to an embodiment of the present disclosure, the state of defoliation of a plant can be determined with high accuracy. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram of an information processing system. [Diagram 2] FIG. 1 is a block diagram showing a configuration of an information processing device. [Figure 3A] 1 is a graph showing canopy coverage. [Figure 3B] 1 is a graph showing time series data of backscattering coefficient. [Figure 4] FIG. 2 is a diagram showing the data structure of a region DB (database). [Diagram 5] 4 is a flowchart showing an operation of the information processing device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] 1 is a schematic diagram of an information processing system S according to the present embodiment. The information processing system S includes an information processing device 1, a user terminal 2, and an artificial satellite 3, which are capable of communicating with each other via a network NW. The network NW includes, for example, a mobile communication network, a fixed communication network, or the Internet.

[0017] 1, for ease of explanation, one information processing device 1, one user terminal 2, and one artificial satellite 3 are illustrated. However, the respective numbers of information processing devices 1, user terminals 2, and one artificial satellite 3 are not limited to this. For example, the process executed by the information processing device 1 of the present embodiment may be executed by a plurality of information processing devices 1 that are distributed.

[0018] The information processing device 1 is installed in a facility such as a data center, etc. The information processing device 1 is a computer such as a server belonging to a cloud computing system or other computing system.

[0019] The internal configuration of the information processing device 1 will be described in detail with reference to FIG.

[0020] The information processing device 1 includes a control unit 11, a communication unit 12, and a storage unit 13. The components of the information processing device 1 are connected to each other so as to be able to communicate with each other.

[0021] The control unit 11 includes, for example, one or more general-purpose processors including a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The control unit 11 may include one or more dedicated processors specialized for specific processing. Instead of including a processor, the control unit 11 may include one or more dedicated circuits. The dedicated circuits may be, for example, a FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit). The control unit 11 may include an ECU (Electronic Control Unit). The control unit 11 transmits and receives any information via the communication unit 12.

[0022] The communication unit 12 includes a communication module compatible with one or more wired or wireless LAN (Local Area Network) standards for connecting to the network NW. The communication unit 12 may include a module compatible with one or more mobile communication standards including LTE (Long Term Evolution), 4G (4th Generation), or 5G (5th Generation). The communication unit 12 may include a communication module compatible with one or more short-range communication standards or specifications including Bluetooth (registered trademark), AirDrop (registered trademark), IrDA, ZigBee (registered trademark), Felica (registered trademark), or RFID. The communication unit 12 transmits and receives any information via the network NW.

[0023] The storage unit 13 includes, but is not limited to, for example, a semiconductor memory, a magnetic memory, an optical memory, or a combination of at least two of these. The semiconductor memory is, for example, a RAM or a ROM. The RAM is, for example, an SRAM or a DRAM. The ROM is, for example, an EEPROM. The storage unit 13 may function, for example, as a main storage device, an auxiliary storage device, or a cache memory. The storage unit 13 may store information resulting from analysis or processing by the control unit 11. The storage unit 13 may store various information related to the operation or control of the information processing device 1, etc. The storage unit 13 may store a system program, an application program, embedded software, etc. The storage unit 13 may be provided outside the information processing device 1 and may be accessed from the information processing device 1. The storage unit 13 includes an area DB, which will be described later.

[0024] The user terminal 2 is, for example, a mobile device such as a mobile phone, a smartphone, a wearable device, or a tablet. Alternatively, the user terminal 2 may be a general-purpose device such as a PC, or a dedicated device. "PC" is an abbreviation for personal computer.

[0025] The artificial satellite 3 includes a synthetic aperture radar (SAR). The artificial satellite 3 transmits or irradiates radio waves such as microwaves from the antenna of the synthetic aperture radar toward the geographical area R (see FIG. 1) to be observed. The geographical area here includes plantations such as rubber plantations. The artificial satellite 3 receives electromagnetic energy scattered from the geographical area R with an antenna and measures time series data of the backscattering coefficient. For example, the backscattering coefficient is the backscattering coefficient (dB) of Sentinel-1's C-band SAR (10m resolution, 12-day period). The backscattering coefficient is analyzed using Google Earth Engine (GEE), which is an analysis environment for remote sensing and GIS (geographic information system), or SNAP, ENVI, SARscape, ArcGIS, QGIS, etc. Note that the SAR frequency of the artificial satellite 3 is not limited to C-band, and X-band or L-band may be adopted.

[0026] Satellite 3 includes a synthetic aperture radar, allowing it to carry out observations day and night, and without being affected by weather conditions such as clouds.

[0027] For the time series data of the backscattering coefficient, four types of polarization can be adopted: VV (vertical wave transmission, vertical wave reception), VH (vertical wave transmission, horizontal wave reception), HH (horizontal wave transmission, horizontal wave reception), and HV (horizontal wave transmission, vertical wave reception). Here, the control unit 11 uses the VH polarization.

[0028] Either of two types, ascending or descending, can be adopted as the orbit direction of the artificial satellite 3. Here, the control unit 11 uses data in the case of ascending.

[0029] The processing contents of the information processing system S of this embodiment will be described in detail below.

[0030] The control unit 11 of the information processing device 1 calculates a backscattering coefficient from data measured by a synthetic aperture radar of the artificial satellite 3, and acquires time-series data of the backscattering coefficient via the network NW.

[0031] Additionally or alternatively, the control unit 11 may store location information of the geographical area and time series data in the storage unit 13 in association with the geographical area to which the radio waves are transmitted, as shown in FIG.

[0032] The control unit 11 determines the occurrence of defoliation of a plant (here, a rubber tree) based on the time series data. A method for determining the occurrence of defoliation will be described with reference to Figs. 3A and 3B. Fig. 3A is a graph showing the canopy coverage rate based on a panoramic photograph taken with a fisheye lens. The horizontal axis indicates time. The vertical axis indicates the ratio (%) of the sky covered by rubber tree leaves when looking directly upward from the forest floor. Fig. 3B is a graph showing time series data of the backscattering coefficient. The horizontal axis indicates time. The vertical axis indicates the backscattering coefficient (dB) of Sentinel-1 SAR. In Fig. 3B, the polarization is VH and the observation orbit is ascending. Figs. 3A and 3B show graphs for the same period. As shown in Figs. 3A and 3B, the periods 31 to 34 when the canopy coverage rate is low (i.e., the period when defoliation occurs) almost coincide with the periods 35 to 38 when the backscattering coefficient increases. Here, even in the same month, the canopy coverage is measured on any one day of the month and displayed on the graph as the value on the first day of the month, whereas the backscattering coefficient is displayed based on data measured from the beginning to the end of the month. Therefore, please note that there may be deviations between periods 31 to 34 and periods 35 to 38. From the above, the control unit 11 determines that the period of increase in the backscattering coefficient in the acquired time series data is the period of defoliation. Defoliation may be either seasonal defoliation or abnormal defoliation due to disease.

[0033] Additionally or alternatively, the occurrence of defoliation may be determined using time series data of one or more other geographical regions of the observed geographical region. Specifically, the control unit 11 may determine that defoliation has occurred in the observed geographical region when it detects that the backscattering coefficient of the observed geographical region has increased compared to the backscattering coefficient of the other one or more geographical regions at a particular time.

[0034] Additionally or alternatively, defoliation may be determined using historical time series data for the observed geographic region. For example, the control unit 11 may determine that defoliation has occurred in the observed geographic region when it detects that the backscattering coefficient at the current time is high compared to the backscattering coefficient at the same time in a previous year.

[0035] Additionally or alternatively, the control unit 11 may correct the time series data according to the topography or slope of the geographical area. For example, the control unit 11 may correct the time series data taking into consideration the effect that the closer the slope is to the vertical relative to the radar irradiation angle, the stronger the reflection, and the closer the slope is to the horizontal, the weaker the reflection. The control unit 11 may also correct the reflection strength based on information such as the variety (clone) or age, height, planting interval or direction of the rubber trees planted. Alternatively, the control unit 11 may set a small geographical evaluation area to reduce the discrepancy between time and place, or create a judgment criterion or judgment model specific to that place to perform the evaluation.

[0036] As an additional example or an alternative example, the control unit 11 determines whether the defoliation is seasonal defoliation or abnormal defoliation. Specifically, the control unit 11 may determine the occurrence of abnormal defoliation based on the deviation rate between the reference time series data (i.e., the time series data when there is no abnormal defoliation) and the acquired time series data. As an alternative example, the control unit 11 may determine the period of seasonal defoliation from the reference time series data, and determine defoliation occurring during a period other than the determined period as abnormal defoliation.

[0037] As an additional example, the control unit 11 may determine the occurrence of leaf fall using an optical sensor on an artificial satellite in addition to the synthetic aperture radar.

[0038] As an additional example, the control unit 11 may perform machine learning such as deep learning using the time series data and the presence or absence of abnormal defoliation as teacher data, and determine the occurrence of defoliation using the constructed learning model.

[0039] As an additional example, the control unit 11 may determine and output the degree of leaf fall based on time-series data.

[0040] As shown in FIG. 4, the control unit 11 stores in the storage unit 13 whether or not leaf fall has occurred in association with the geographical region of the observation target.

[0041] The control unit 11 outputs information related to the occurrence of leaf fall to the user terminal 2. The information related to the occurrence of leaf fall may include information indicating whether or not leaf fall has occurred and location information of the location where leaf fall has occurred.

[0042] FIG. 5 is a flowchart of an information processing method performed by the information processing device 1.

[0043] In S1, the control unit 11 acquires time-series data of the backscattering coefficient based on data measured by the synthetic aperture radar of the artificial satellite 3. In S2, the control unit 11 determines the occurrence of defoliation of plants based on the time-series data. In S3, the control unit 11 outputs information regarding the occurrence of defoliation.

[0044] Although the present disclosure will be described based on various drawings and examples, it should be noted that those skilled in the art may make various modifications and alterations based on the present disclosure. Other modifications are possible within the scope of the present disclosure. For example, the functions included in each means or step can be rearranged so as not to cause logical inconsistencies, and multiple means or steps can be combined into one or divided.

[0045] For example, in the above embodiment, a program for executing all or part of the functions or processes of the information processing device 1 can be recorded in a computer-readable recording medium. The computer-readable recording medium includes a non-transitory computer-readable medium, such as a magnetic recording device, an optical disk, a magneto-optical recording medium, or a semiconductor memory. The program is distributed by, for example, selling, transferring, or lending a portable recording medium such as a DVD (Digital Versatile Disc) or a CD-ROM (Compact Disc Read Only Memory) on which the program is recorded. The program may also be distributed by storing the program in the storage of an arbitrary server and transmitting the program from the arbitrary server to another computer. The program may also be provided as a program product. The present disclosure can also be realized as a program executable by a processor. [Industrial Applicability]

[0046] According to the present disclosure, the state of defoliation of plants can be determined with high accuracy.

[0047] [Contribution to the United Nations-led Sustainable Development Goals (SDGs)] The SDGs have been proposed to realize a sustainable society. One embodiment of the present invention is expected to contribute to "No. 8 - Decent Work and Economic Growth." [Explanation of symbols]

[0048] 1. Information processing device

Claims

1. An information processing device including a control unit, a communication unit, and a storage unit, the control unit comprising: Obtaining time series data of backscattering coefficient based on data measured by a synthetic aperture radar of a satellite that transmits radio waves to a geographical area; determining a state of defoliation of plants based on the time-series data; and outputting information regarding the occurrence status; An information processing device that performs operations including the steps of:

2. 2. The information processing device according to claim 1, The operation includes storing location information of the geographical area in association with the time series data in the storage unit, and outputting location information of a location where leaf fall has occurred.

3. 2. The information processing device according to claim 1, The information processing device determines the occurrence of defoliation using time series data of one or more other geographical regions.

4. 2. The information processing device according to claim 1, An information processing device in which the occurrence of defoliation is determined using past time series data in the geographical area.

5. 2. The information processing device according to claim 1, The information processing device determines the occurrence of fallen leaves using a VH polarized wave indicating vertical wave transmission and horizontal wave reception, or an HV polarized wave indicating horizontal wave transmission and vertical wave reception.

6. 2. The information processing device according to claim 1, The information processing device, wherein the operation includes correcting the time series data according to a topography or a slope of the geographical area.

7. An information processing method by an information processing device including a control unit, a communication unit, and a storage unit, Obtaining time series data of backscattering coefficient based on data measured by a synthetic aperture radar of a satellite that transmits radio waves to a geographical area; determining a state of defoliation of plants based on the time-series data; and outputting information regarding the occurrence status; An information processing method comprising:

8. A program for causing a computer to function as the information processing device according to claim 1.

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