Concentration measurement method, concentration measurement device, and program

Abstract

A concentration measurement device 100 of the present invention includes an acquisition unit 121 that acquires the height position of a float, which is suspended in a liquid and the floating height of which changes depending on the concentration of the liquid, the height position being measured using radio waves, and a measurement unit 122 that measures the concentration of the liquid on the basis of the height position.

Description

Concentration measurement method, concentration measurement device, and program

[0001] The present invention relates to a method for measuring the concentration of a liquid, and also to a concentration measurement device, a concentration measurement system, and a program.

[0002] Patent Document 1 describes a method for measuring the salinity of brine in salt fields. First, a method using a hydrometer / Baume hydrometer is described as a general method for measuring brine concentration. However, this method requires the collection of brine samples from the salt fields, but the large area of ​​the salt fields makes it difficult to collect samples. As a result, the method describes the problem that it becomes difficult to frequently observe the brine concentration, resulting in large variations in the amount of salt produced.

[0003] Furthermore, Patent Document 1 describes another method for measuring salinity using a novel device based on the principle of buoyancy. Specifically, the device has a hemispherical body and a rod with a scale attached to the top of the body. When a desired salinity is reached in saltwater, the rod floats up to the corresponding scale. Therefore, the saltwater concentration can be measured by observing the scale on the device floating in the salt field from a distance.

[0004] Special Publication No. 2006-511795

[0005] However, the technique described in Patent Document 1 has problems in that it is not possible to measure the salt concentration with high accuracy and that the measurement is time-consuming. ２Many of the devices have an area of ​​1000 m2 or more, and some even have an area of ​​even more. Therefore, when floating the above-mentioned devices on such a large salt field, it is necessary to observe the scale of the device from a distance or to move closer to each device to observe it. When observing the device from a distance, it is difficult to observe the scale with high accuracy. On the other hand, when moving closer to each device to observe the scale, the movement is time-consuming. As a result, a problem occurs in that it is not possible to measure the salt concentration easily and accurately. Furthermore, this problem is not limited to when measuring the salinity of saltwater in a salt field, but can occur when measuring the concentration of any liquid in any location.

[0006] Therefore, an object of the present disclosure is to provide a method for easily and accurately measuring the concentration of a liquid.

[0007] A concentration measurement method according to one embodiment of the present disclosure includes acquiring a height position of a float, the height of which changes depending on the concentration of a liquid suspended in the liquid, measured using radio waves, and measuring the concentration of the liquid based on the height position.

[0008] Furthermore, a concentration measuring device according to one embodiment of the present disclosure is configured to include: an acquisition unit that acquires the height position of a float, the floating height of which changes depending on the concentration of a liquid suspended in the liquid, measured using radio waves; and a measurement unit that measures the concentration of the liquid based on the height position.

[0009] Furthermore, a concentration measurement system according to one embodiment of the present disclosure is configured to include: a float that floats in a liquid and whose floating height changes depending on the concentration of the liquid; a position measurement device that measures the height position of the float using radio waves; and a concentration measurement device having an acquisition unit that acquires the measured height position of the float and a measurement unit that measures the concentration of the liquid based on the height position.

[0010] Furthermore, a program according to one embodiment of the present disclosure is configured to cause a computer to execute a process of acquiring the height position of a float, the height of which changes depending on the concentration of the liquid suspended in the liquid, measured using radio waves, and measuring the concentration of the liquid based on the height position.

[0011] With the above-described configuration, the present disclosure can measure the concentration of a liquid easily and with high accuracy.

[0012] FIG. 1 is a block diagram showing the overall configuration of a salinity concentration measurement system according to a first embodiment of the present disclosure. FIG. 2 is a diagram showing an example of the configuration of a float disclosed in FIG. 1. FIG. 3 is a block diagram showing the configuration of a concentration measurement device disclosed in FIG. 1. FIG. 4 is a flowchart showing the operation of the concentration measurement device disclosed in FIG. 1. FIG. 5 is a diagram showing another example of the configuration of a float disclosed in FIG. 1. FIG. 6 is a block diagram showing the hardware configuration of a concentration measurement device according to a second embodiment of the present disclosure. FIG. 7 is a block diagram showing the configuration of a concentration measurement device according to a second embodiment of the present disclosure.

[0013] <Embodiment 1> A first embodiment of the present disclosure will be described with reference to Figures 1 to 6. Figures 1 to 3 are diagrams for explaining the configuration of a salinity concentration measurement system, and Figure 4 is a diagram for explaining the processing operation of the salinity concentration measurement system. Also, Figures 5 and 6 are diagrams for explaining another example of the configuration of the salinity concentration measurement system.

[0014] The salinity measurement system of this embodiment is for measuring the salinity of saltwater in a salt field. In particular, the salinity measurement system of this embodiment is suitable for measuring the salinity of saltwater in a solar salt field, where salt-containing water such as seawater or salt lakes is evaporated and concentrated by solar heat to produce crystallized salt. In other words, in the case of a solar salt field, the salt field is located over an area of ​​several kilometers. ２ However, the salinity concentration measurement system of the present disclosure may be used in salt fields of any size.

[0015] The system of the present disclosure is not limited to use in measuring the salinity of saltwater in salt fields, but can also be applied to measuring the concentration of any liquid present in any location. For example, it may be applied to measuring the salinity of liquid present in lakes, oceans, etc., or to measuring the concentration of colloidal solutions such as mud. In this case, the liquid to be measured is, for example, a solution in which a solute is dissolved in a solvent, and the concentration is the ratio of the solute in the solution. However, the concentration of any substance dissolved in any liquid may be measured. Furthermore, the measurement location may be any location.

[0016] As shown in Figure 1, the salinity concentration measurement system in this embodiment includes a float 30 floating in saltwater W in a salt field, a position measurement device 20 that measures the height position of the float, and a concentration measurement device 10 that measures the salinity concentration of the saltwater W. In this embodiment, a synthetic aperture radar (SAR) mounted on an artificial satellite A, as described below, is used to measure the salinity concentration of the saltwater W. Each component will be described in detail below.

[0017] The floats 30 are floating objects placed within the salt fields and are made of a buoyant material that floats in the salt water W within the salt fields. The floats 30 are placed, for example, at multiple locations within the vast salt fields. Specifically, in this embodiment, a pair of floats 30 are placed at one location. As an example, as shown in FIG. 2 , the floats 30 are paired in two, a first float 31 and a second float 32, and are placed at a predetermined location. Here, the first float 31 and the second float 32 are each formed in a cylindrical shape, have the same circular cross-sectional area, and have different heights h1 and h2, with the height h1 of the first float 31 being lower than the height h2 of the second float 32. The upper surfaces of the first float 31 and the second float 32 are configured as reflectors that efficiently reflect radio waves irradiated from a synthetic aperture radar (hereinafter referred to as "SAR") mounted on the artificial satellite A, as described below, in the SAR direction. For example, the first float 31 and the second float 32 may each have a reflecting plate formed on their upper surface as a reflecting portion, or a corner reflector may be mounted on the top of each float as a reflecting portion. Such reflecting portions correspond to the height positions of the respective floats that are measured, as described below. The first float 31 and the second float 32 are configured to have different buoyancy amounts depending on the saltwater concentration by providing differences in density, overall mass, cross-sectional area, height, etc., as described below. As a result, the first float 31 and the second float 32 are configured such that the measured height positions, which are the positions of the reflecting portions, are different for saltwater W with the same saltwater concentration.

[0018] Here, the first float 31 and the second float 32 are arranged so that the height direction of their cylindrical shapes is positioned vertically and they float in the saltwater W. For example, the first float 31 and the second float 32 are arranged in the saltwater W in a state where they are housed in a predetermined frame or connected by a predetermined string or rod, thereby regulating the attitude of the floats themselves. In this case, the first float 31 and the second float 32 are preferably arranged along the direction of irradiation of radio waves by the SAR. In other words, the first float 31 and the second float 32 are preferably arranged along a direction perpendicular to the direction of travel of the artificial satellite A on which the SAR is mounted. In this case, too, their arrangement is regulated by a predetermined frame, string, rod, or the like, as described above.

[0019] Furthermore, the first float 31 and the second float 32 are configured to have different densities ρ1 and ρ2. For example, the density ρ1 of the first float 31 is configured to be greater than the density ρ2 of the second float 32. Therefore, as shown in FIG. 2 , the first float 31 and the second float 32 sink to different volumes in saltwater W of the same salinity, with the first float 31 sinking to a shorter height than the second float 32. As a result, the height positions of the tops of the first float 31 and the second float 32, i.e., the height positions of the radio wave reflecting portions, will differ in saltwater W of the same salinity, and the difference d between them will correspond to the salinity of the saltwater W. In other words, when the salinity of the saltwater W changes, the height positions of the first float 31 and the second float 32 will change, and the difference d will also change. The densities of the first float 31 and the second float 32 do not need to be uniform throughout each float. For example, increasing the density of the bottom end of the float can stabilize the float's floating posture. However, the first float 31 and the second float 32 may have the same density, in which case, it is preferable to form them with different cross-sectional shapes. As a result, their sinking heights (i.e., floating amounts) will differ in saltwater W of the same salinity, and the height positions of the radio wave reflectors will also differ. The difference d between these will correspond to the salt concentration of the saltwater W. In other words, the difference d described above can be said to eliminate the effects of height changes that depend on factors other than the concentration of the saltwater W. For example, if the saltwater W in a salt field changes in level, this change in water level will be reflected directly as a change in the height of both floats. However, by obtaining the difference d between the height positions of the floats, the change in the saltwater W level can be eliminated. As a result, as described below, using this difference d enables more accurate measurement of the salt concentration.

[0020] Satellite A is a so-called SAR satellite and is equipped with a synthetic aperture radar (SAR). SAR can measure the distance to an object by emitting radio waves to the ground and observing the radio waves reflected from the object. In this embodiment, satellite A targets a float 30 floating in salt water W in a salt pan, emitting radio waves to the float 30 and transmitting the observed radio wave information to a position measurement device 20. When using data from two or more SARs, the change in distance to the object can be measured with high accuracy, for example, by using a technique called interferometric SAR. For example, when data from two or more SARs is acquired on different orbits, height can be obtained as a result of analyzing the change in distance due to the different orbits. Furthermore, when data from two or more SARs is acquired on different dates, the change in height can be obtained with high accuracy based on the change in distance between those dates, and the height position itself can be obtained with high accuracy by accumulating the change in height. In this case, the initial position of each float is measured and stored in advance, and the height of each float is calculated by multiplying the change in height of each float by the measured value as described above, and the difference d can be calculated.

[0021] The position measurement device 20 is composed of one or more information processing devices including a calculation device and a storage device. The position measurement device 20 receives radio wave information acquired from the satellite A as described above and measures the height position of the float 30 from the radio wave information, for example, using the method described above. In particular, in this embodiment, the position measurement device 20 measures the height positions of the pair of first and second floats 31 and 32, which are arranged at predetermined locations as described above, and also measures the difference d between them. The position measurement device 20 stores position information for each pair of floats 30 arranged at multiple locations within the salt field, and measures the height positions and the difference d between each pair of floats 30 arranged at each location based on radio wave information including position information from the SAR. The position measurement device 20 then transmits the measured height positions and the difference d, along with the identification information of the floats located at each location, to the concentration measurement device 10 connected via the network N. The position measurement device 20 may transmit only the measured height position to the concentration measurement device 10, and may not calculate the difference and transmit it to the concentration measurement device 10.

[0022] The concentration measuring device 10 (salt concentration measuring device) is composed of one or more information processing devices each including a calculation device and a storage device. The concentration measuring device 10 is, for example, an information processing device managed by a business operator that manages the salinity of salt water W in a salt field. As shown in FIG. 3, the concentration measuring device 10 includes an acquisition unit 11 and a measurement unit 12. The functions of the acquisition unit 11 and the measurement unit 12 can be realized by the calculation device executing a program for realizing each function stored in the storage device. The concentration measuring device 10 also includes a location information storage unit 16. The location information storage unit 16 is composed of a storage device. Each component and its operation will be described in detail below.

[0023] The acquisition unit 11 acquires the height position information of the floats transmitted from the position measurement device 20 (step S1 in FIG. 4 ) and stores it in the position information storage unit 16. At this time, the acquisition unit 11 associates and stores the transmitted height position information of the paired floats with the identification information corresponding to the floats placed at each location. For example, in the example of FIG. 2 , the acquisition unit 11 acquires and stores the height positions of the first float 31 and the second float 32 along with the identification information corresponding to the floats at a predetermined location. Note that if the position measurement device 20 transmits information on the difference d between the first float 31 and the second float 32 in addition to the height position information of these floats, the acquisition unit 11 may also acquire and store the information on the difference d.

[0024] The measurement unit 12 measures the salinity concentration of the saltwater W in which the float 30 floats based on the acquired height position of the float 30 (step S2 in FIG. 4 ). In this embodiment, the measurement unit 12 measures the salinity concentration of the saltwater W based on the difference d in height positions between the paired first float 31 and second float 32. Here, in the example shown in FIG. 2 , as described above, the first float 31 and the second float 32 are each formed in a cylindrical shape, have the same circular cross-sectional area, and have different heights h1 and h2. Furthermore, the first float 31 and the second float 32 are configured with different densities ρ1 and ρ2, and therefore sink to different heights x1 and x2 relative to the saltwater W, resulting in a difference d in height position. In this case, the salinity concentration ρ of the saltwater W can be calculated, for example, using the following equation 1:

[0025] The measurement unit 12 measures the salinity concentration ρ as described above for each location where the float 30 is placed, based on the height position information of the float 30 associated with that location. The measurement unit 12 then stores the measured salinity concentration ρ in the position information storage unit 16 in association with the location where the float is placed. The measurement unit 12 may output the measured salinity concentration ρ together with information about the corresponding location, or may compare the measured salinity concentration ρ with a preset threshold value or a value measured thereafter and output the comparison result.

[0026] As described above, the salinity concentration measurement system of this embodiment can measure the salinity of saltwater in a salt field by measuring the height position of the float 30 using the SAR mounted on the artificial satellite A. Therefore, the salinity can be measured easily and with high accuracy even in a salt field with a large area.

[0027] While the above example illustrates the case where the height position of the float 30 is measured using a SAR mounted on a satellite A, the SAR does not necessarily have to be mounted on a satellite A and may be mounted on an aircraft, other flying object, or a building. Furthermore, the height position of the float 30 does not necessarily have to be measured using a SAR and may be measured using any method using radio waves emitted from above the salt fields. Alternatively, in good weather, electromagnetic waves in the THz band or optical frequency band may be used. That is, high-frequency electromagnetic waves have poor linearity and poor penetration, but can be used under conditions where there are no obstructions. Furthermore, the concentration measurement device 10 is not necessarily limited to acquiring the height position of the float 30 measured by the position measurement device 20. The height position of the float 30 may be acquired directly from a device such as a SAR, or may be acquired from any device.

[0028] Here, modifications of the configuration of the salinity concentration measurement system configured as described above, particularly modifications of the float 30, will be described with reference to FIGS. 5 and 6. FIG.

[0029] As shown in FIG. 5 , the float 30 in a modified example of this embodiment may be configured as a pair of a third float 33 and a fourth float 34. The third float 33 is, for example, made of a highly corrosion-resistant metal thin film material and is configured to float on the surface of saltwater W regardless of its salinity, with its upper surface configured as a reflector. The fourth float 34 is configured to change its floating height in response to the osmotic pressure of the saltwater W. Specifically, the fourth float 34 includes a hollow cylindrical body 34a, a permeation membrane 34b that closes the lower portion of the cylindrical body 34a and is positioned within the saltwater W, a reflector 34c that closes the upper portion of the cylindrical body 34a, and a liquid 34d, such as water, contained within the cylindrical body 34a, i.e., between the permeation membrane 34b and the reflector 34c. As a result, an osmotic pressure F is applied vertically to the permeation membrane 34b in response to changes in the salinity of the saltwater W, causing the reflector 34c on the upper surface to move vertically M, thereby changing its height. In this way, the third float 33 and the fourth float 34 have different measured height positions, which are the positions of the reflecting parts, for salt water W with the same salt water concentration, and the difference d in height positions between the third float 33 and the fourth float 34 changes according to changes in the salt concentration.

[0030] In this configuration, the satellite A can use SAR to measure the height positions of the third float 33 and the fourth float 34, and the concentration measurement device 10 can acquire these measurements. The concentration measurement device 10 can then determine the density ρ of the saltwater W by using osmotic pressure or the like based on the acquired difference d in height positions between the third float 33 and the fourth float 34. In this case, the concentration measurement device 10 may, for example, prepare in advance a correspondence relationship between the difference d in height positions of the paired floats and the salinity ρ of the saltwater W, and measure the value of the salinity ρ corresponding to the measured difference d in height positions of the floats as the salinity concentration at the time of measurement.

[0031] As shown in FIG. 6 , the float 30 in another modification of this embodiment may be configured as a pair of a third float 33 and a fifth float 35. The third float 33 is similar to the float shown in FIG. 5 and is configured to float on the surface of saltwater W regardless of its salinity, with its upper surface serving as a reflector. The fifth float 35 includes a hydrometer 35a having a predetermined density and disposed in the saltwater W, whose height position within the saltwater W changes depending on the salinity, and an upper reflector 35c connected to the hydrometer 35a via a rod 35b. As a result, the hydrometer 35a is displaced vertically in response to changes in the salinity of the saltwater W, and the upper reflector 34c is moved vertically accordingly, changing its height. In this way, the third float 33 and the fifth float 35 have different measured height positions, which are the positions of the reflecting parts, for salt water W with the same salt water concentration, and the difference d in height positions between the third float 33 and the fifth float 35 changes according to changes in the salt concentration.

[0032] In this configuration, the satellite A can use SAR to measure the height positions of the third float 33 and the fifth float 35, and the concentration measurement device 10 can acquire these measurements. The concentration measurement device 10 can then determine the density ρ of the saltwater W by using the density of the hydrometer unit 35a and the like based on the acquired difference d in height positions between the third float 33 and the fifth float 35. In this case, the concentration measurement device 10 may, for example, prepare in advance a correspondence relationship between the difference d in height positions of the paired floats and the salinity concentration ρ of the saltwater W, and measure the value of the salinity concentration ρ corresponding to the measured difference d in height positions of the floats as the salinity concentration at the time of measurement.

[0033] Although the above example illustrates a case in which the float 30 placed at the location where the salinity concentration is measured is composed of two paired floats, the float 30 may be composed of only one float. For example, it is possible to measure the height position of one float 30 as described above using radio waves, as well as the height position of the water surface of the saltwater W in the salt field, and then measure the salinity concentration of the saltwater W using the difference between the height position of the water surface of the saltwater W and the height position of the float 30. The water surface height can also be obtained by simply measuring the reflection from the water surface, but the reflection of radio waves can also be enhanced by floating particles, a film, or the like on the water surface. Alternatively, the water surface can be measured using a measurement method that uses radio waves, in which the receiver and transmitter are mounted on different aircraft or the like to obtain specular reflection of radio waves with high sensitivity. Alternatively, the height of land can be used instead of the height position of the water surface of the saltwater W to measure the difference in height between the land and the float 30. In addition, since the water surface of the salt fields is a mirror surface, it is possible to calculate the salinity concentration by utilizing the interference of the mirror image of the reflecting part of the float 30. It is also possible to calculate the salinity concentration by using the difference in height between the float 30 and the height of another object or point that does not move and serves as a reference.

[0034] <Embodiment 2> Next, a second embodiment of the present disclosure will be described with reference to Fig. 7 and Fig. 8. Fig. 7 and Fig. 8 are block diagrams showing the configuration of a concentration measurement device in embodiment 2. Note that this embodiment shows an outline of the configuration of the concentration measurement device described in the above embodiment.

[0035] First, the hardware configuration of the concentration measurement device 100 of this embodiment will be described with reference to Fig. 7. The concentration measurement device 100 is configured as a general information processing device, and is equipped with the following hardware configuration, for example: CPU (Central Processing Unit) 101 (arithmetic unit); ROM (Read Only Memory) 102 (storage device); RAM (Random Access Memory) 103 (storage device); programs 104 loaded into RAM 103; storage device 105 that stores the programs 104; drive device 106 that reads and writes from / to a storage medium 110 external to the information processing device; communication interface 107 that connects to a communication network 111 external to the information processing device; input / output interface 108 that inputs and outputs data; and bus 109 that connects the various components.

[0036] The concentration measurement device 100 can be equipped with an acquisition unit 121 and a measurement unit 122 shown in FIG. 8 by having the CPU 101 acquire and execute the program group 104. The program group 104 is stored in advance in the storage device 105 or the ROM 102, for example, and is loaded into the RAM 103 and executed by the CPU 101 as needed. The program group 104 may be supplied to the CPU 101 via the communication network 111, or may be stored in advance in the storage medium 110, and the drive device 106 may read out the program and supply it to the CPU 101. However, the acquisition unit 121 and the measurement unit 122 described above may be constructed using dedicated electronic circuits for realizing such means.

[0037] 7 shows an example of the hardware configuration of the information processing device that is the concentration measurement device 100, and the hardware configuration of the information processing device is not limited to the above-described case. For example, the information processing device may be configured with only a part of the above-described configuration, such as excluding the drive device 106. Furthermore, instead of the CPU described above, the information processing device may use a GPU (Graphics Processing Unit), a DSP (Digital Signal Processor), an MPU (Micro Processing Unit), an FPU (Floating Point Number Processing Unit), a PPU (Physics Processing Unit), a TPU (Tensor Processing Unit), a quantum processor, a microcontroller, or a combination thereof.

[0038] The acquisition unit 121 acquires the height position of a float whose floating height changes depending on the concentration of the liquid suspended in the liquid. At this time, the acquired height position of the float is measured using radio waves, for example, by emitting radio waves from the sky. For example, the float may be composed of two floats whose measured height positions are different for liquid of the same concentration, and the difference between the measured height positions changes depending on the concentration, and the acquisition unit 121 acquires the height positions of these two floats.

[0039] The measuring unit 122 measures the concentration of the liquid based on the height position. At this time, the height position of the float changes depending on the concentration of the liquid, so the concentration of the liquid in which the float is floating can be measured by using the height position. In particular, the concentration can be measured by using the difference in the height positions of the two floats as described above.

[0040] With the above-described configuration, the present disclosure can measure the concentration of a liquid by measuring the height position of the float using radio waves, making it possible to measure the concentration easily and with high accuracy even when the liquid is present in a large area.

[0041] The above-described program can be stored and supplied to a computer using various types of non-transitory computer-readable media. Non-transitory computer-readable media include various types of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (e.g., flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (e.g., magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, and semiconductor memories (e.g., mask ROMs, PROMs (Programmable ROMs), EPROMs (Erasable PROMs), flash ROMs, and RAMs (Random Access Memory)). The program may also be supplied to a computer by various types of transitory computer-readable media. Examples of transitory computer-readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer-readable media can be supplied to a computer via wired communication paths such as electric wires and optical fibers, or via wireless communication paths.

[0042] Although the present disclosure has been described above with reference to the above-described embodiments, the present disclosure is not limited to the above-described embodiments. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, at least one or more of the functions of the acquisition unit 121 and the measurement unit 122 described above may be executed by an information processing device installed and connected anywhere on a network, that is, may be executed by so-called cloud computing.

[0043] <Supplementary Notes> Some or all of the above embodiments can also be described as the following supplementary notes. Below, an outline of the configurations of the concentration measurement method, concentration measurement device, and program of the present invention will be described. However, the present invention is not limited to the following configurations. (Supplementary Note 1) A concentration measurement method comprising: acquiring a height position of a float, the floating height of which changes depending on the concentration of a liquid suspended in the liquid, measured using radio waves; and measuring the concentration of the liquid based on the height position. (Supplementary Note 2) A concentration measurement method according to Supplementary Note 1, comprising: acquiring height positions of two floats that float in the liquid with the same concentration so that the measured height positions are different; and measuring the concentration of the liquid based on the height positions of the two floats. (Supplementary Note 3) A concentration measurement method according to Supplementary Note 2, comprising: acquiring height positions of two floats that float in the liquid so that the difference between the measured height positions changes depending on the concentration of the liquid; and measuring the concentration of the liquid based on the difference between the height positions of the two floats. (Supplementary Note 4) The concentration measurement method according to Supplementary Note 2 or 3, wherein the height positions of each of the two floats having different densities are obtained. (Supplementary Note 5) The salinity concentration measurement method according to Supplementary Note 2 or 3, wherein the height position of at least one of the floats floating so that the measured height position changes according to the osmotic pressure of the liquid is obtained. (Supplementary Note 6) The concentration measurement method according to any of Supplements 2 to 5, wherein the height positions of each of the two floats are obtained, one of which floats at the water surface of the liquid and the other float floats above the water surface of the liquid. (Supplementary Note 7) The concentration measurement method according to any of Supplements 1 to 6, wherein the height positions of the floats measured using a synthetic aperture radar mounted on an airborne vehicle are obtained. (Supplementary Note 8) The concentration measurement method according to Supplementary Note 7, wherein a reflecting portion that reflects radio waves irradiated by the synthetic aperture radar in the direction of the synthetic aperture radar is formed on an upper portion of the float.(Supplementary Note 9) The concentration measurement method according to Supplementary Note 7 or 8, comprising acquiring height positions of two floats arranged along the irradiation direction of radio waves by the synthetic aperture radar. (Supplementary Note 10) A concentration measurement device comprising: an acquisition unit that acquires the height position of a float, the floating height of which changes depending on the concentration of a liquid suspended in the liquid, measured using radio waves; and a measurement unit that measures the concentration of the liquid based on the height position. (Supplementary Note 10.1) The concentration measurement device according to Supplementary Note 10, wherein the acquisition unit acquires the height positions of two floats that float so that the measured height positions are different for the liquid of the same concentration, and the measurement unit measures the concentration of the liquid based on the height positions of the two floats. (Supplementary Note 10.2) The concentration measuring device according to Supplementary Note 10.1, wherein the acquisition unit acquires the height positions of two floats that float such that the difference between the measured height positions changes according to the concentration of the liquid, and the measurement unit measures the concentration of the liquid based on the difference between the height positions of the two floats. (Supplementary Note 10.3) The concentration measuring device according to Supplementary Note 10.1 or 10.2, wherein the acquisition unit acquires the height positions of two floats that have different densities. (Supplementary Note 10.4) The concentration measuring device according to Supplementary Note 10.1 or 10.2, wherein the acquisition unit acquires the height position of at least one of the floats that floats such that the measured height position changes according to the osmotic pressure of the liquid. (Supplementary Note 10.5) A concentration measuring device according to any one of Supplementary Notes 10.1 to 10.4, wherein the acquisition unit acquires the height positions of two floats, one of which is floating at the water surface of the liquid and the other of which is floating above the water surface of the liquid.(Supplementary Note 11) A concentration measurement system comprising: a float that floats in a liquid and whose floating height changes depending on the concentration of the liquid; a position measurement device that measures the height position of the float using radio waves; and a concentration measurement device having: an acquisition unit that acquires the measured height position of the float; and a measurement unit that measures the concentration of the liquid based on the height position. (Supplementary Note 11.1) A concentration measurement system according to Supplementary Note 11, wherein the floats consist of two floats that float so that the measured height positions are different for the liquid of the same concentration, the position measurement device measures the height positions of each of the two floats, the acquisition unit of the concentration measurement device acquires the height positions of each of the two floats, and the measurement unit of the concentration measurement device measures the concentration of the liquid based on the height positions of the two floats. (Supplementary Note 11.2) A concentration measurement system as set forth in Supplementary Note 11.1, wherein the floats consist of two floats that float such that the difference in their measured height positions changes according to the concentration of the liquid, the position measurement device measures the height positions of each of the two floats, the acquisition unit of the concentration measurement device acquires the height positions of each of the two floats, and the measurement unit of the concentration measurement device measures the concentration of the liquid based on the difference in height positions of the two floats. (Supplementary Note 11.3) A concentration measurement system as set forth in Supplementary Note 11.1 or 11.2, wherein the floats consist of two floats with different densities. (Supplementary Note 11.4) A concentration measurement system as set forth in Supplementary Note 11.1 or 11.2, wherein the floats consist of two floats, including at least one float that floats such that the height position measured changes according to the osmotic pressure of the liquid. (Appendix 11.5) A concentration measurement system according to any one of Appendices 11.1 to 11.4, wherein the floats consist of two floats, one of which floats at a height position at the water surface of the liquid, and the other float floats at a height position above the water surface of the liquid.(Supplementary Note 11.6) A concentration measurement system as set forth in any of Supplements 11 to 11.5, wherein the position measurement device measures the height position of the float using information measured using a synthetic aperture radar mounted on an airborne vehicle. (Supplementary Note 11.7) A concentration measurement system as set forth in Supplementary Note 11.6, wherein the float has a reflecting portion on an upper portion thereof that reflects radio waves emitted by the synthetic aperture radar in the direction of the synthetic aperture radar. (Supplementary Note 11.8) A concentration measurement system as set forth in Supplementary Note 11.6 or 11.7, wherein the float consists of two floats arranged along the direction of emission of radio waves by the synthetic aperture radar. (Supplementary Note 12) A program for causing a computer to execute a process of acquiring the height position of a float, the floating height of which changes depending on the salinity concentration of a liquid suspended in the liquid, measured using radio waves, and measuring the concentration of the liquid based on the height position.

[0044] The present invention claims the benefit of priority based on the patent application of Japanese Patent Application No. 2022-100972 filed on June 23, 2022 in Japan, and all contents described in the patent application are incorporated herein by reference.

[0045] REFERENCE SIGNS LIST 10 Concentration measurement device 11 Acquisition unit 12 Measurement unit 16 Position information storage unit 20 Position measurement device 30, 31, 32, 33, 34, 35 Float A Artificial satellite W Salt water 100 Concentration measurement device 101 CPU 102 ROM 103 RAM 104 Program group 105 Storage device 106 Drive device 107 Communication interface 108 Input / output interface 109 Bus 110 Storage medium 111 Communication network 121 Acquisition unit 122 Measurement unit

Claims

1. The height position of the float, which is measured using radio waves and whose floating height changes depending on the concentration of the liquid suspended in the liquid, is acquired; measuring a concentration of the liquid based on the height position; Concentration measurement method.

2. The concentration measurement method according to claim 1, Acquire the height positions of two floats that float so that the height positions measured relative to the liquid of the same concentration are different; measuring the concentration of the liquid based on the height positions of the two floats; Concentration measurement method.

3. The concentration measurement method according to claim 2, Acquire the height positions of the two floats that float such that the difference between the height positions measured changes depending on the concentration of the liquid; measuring the concentration of the liquid based on the difference in height between the two floats; Concentration measurement method.

4. The concentration measurement method according to claim 2, acquiring a height position of at least one of the floats that floats such that a height position measured according to an osmotic pressure of the liquid changes; Concentration measurement method.

5. The concentration measurement method according to claim 2, Acquire the height positions of the two floats, one of which is floating at the water surface level of the liquid and the other of which is floating above the water surface level of the liquid; Concentration measurement method.

6. The concentration measurement method according to claim 1, Obtaining the height position of the float measured using a synthetic aperture radar mounted on the flying object; Concentration measurement method.

7. The concentration measurement method according to claim 6, A reflector that reflects radio waves emitted by the synthetic aperture radar in the direction of the synthetic aperture radar is formed on an upper portion of the float. Concentration measurement method.

8. The concentration measurement method according to claim 6, acquiring height positions of the two floats arranged along the direction of irradiation of radio waves by the synthetic aperture radar; Concentration measurement method.

9. A float that floats in a liquid and whose floating height changes depending on the concentration of the liquid; a position measuring device that measures the height position of the float using radio waves; a concentration measuring device including: an acquisition unit that acquires the measured height position of the float; and a measurement unit that measures the concentration of the liquid based on the measured height position; A concentration measurement system equipped with

10. The concentration measurement system according to claim 9, The float includes two floats that float so that their height positions measured relative to the liquid of the same concentration are different, The position measurement device measures the height positions of the two floats, The acquisition unit of the concentration measuring device acquires height positions of the two floats, the measurement unit of the concentration measurement device measures the concentration of the liquid based on height positions of the two floats. Concentration measurement system.