Marine organism acoustic target characteristic measuring device and measuring method

Abstract

The invention relates to a marine organism acoustic target characteristic measuring device and method, the device comprises an upper support, a lower support, a buoy, a transducer, a split beam transceiver, a wireless transmission network bridge and a server, the middle part of the lower support is provided with an accommodating space, and a to-be-measured marine organism is located in the accommodating space; the buoy is connected between the upper support and the lower support, and a cavity is formed in the buoy. The transducer is arranged in the accommodating space of the lower bracket, is positioned below the buoy and is used for transmitting pulse sound waves to the marine organism to be detected; the split beam transceiver is located in the cavity of the buoy, and the split beam transceiver is used for receiving data collected by the transducer; the wireless transmission network bridge is connected with the split beam transceiver; and the server is connected with the wireless transmission network bridge. According to the device provided by the invention, the marine organism acoustic target intensity is calculated by the server, and the marine organism target intensity characteristic spectrogram is drawn through the target intensity result, so that the reliability of nuclear power cold source disaster-causing marine organism intrusion front-end early warning is ensured.

Description

Technical Field

[0001] The invention belongs to the field of marine biological measurement, and in particular relates to a marine biological acoustic target characteristic measurement device and a measurement method. Background Art

[0002] The cooling water supply of the nuclear power plant's circulating cooling water system and other important equipment all rely on the nuclear power plant's water intake. The operating status of the water intake directly affects the safe and stable operation of the power plant. In recent years, large-scale marine biological outbreaks in coastal nuclear power plants along my country's coast have had a serious impact on the safety of cold sources. In order to achieve effective monitoring of marine biological outbreaks and provide early warning, the determination of marine biological target characteristics has become a top priority. The acoustic target characteristic determination device has become an important part of it, and has become a difficult problem in the current stage of marine biological acoustic target characteristic determination. Summary of the invention

[0003] The purpose of the present invention is to provide an improved marine biological acoustic target characteristic determination device and determination method, so as to ensure the reliability of the front-end warning of nuclear power cold source disaster-causing marine biological invasion.

[0004] In order to achieve the above object, a technical solution adopted by the present invention is:

[0005] A device for determining characteristics of marine biological acoustic targets, the device comprising:

[0006] An upper bracket and a lower bracket, wherein the upper bracket is located above the lower bracket, and a receiving space is provided in the middle of the lower bracket, and the marine organism to be tested is located in the receiving space;

[0007] A buoy, wherein the buoy is connected between the upper bracket and the lower bracket, and the buoy has a cavity therein;

[0008] The transducer is arranged in the accommodating space of the lower bracket and is located below the buoy. The transducer is used to emit pulse sound waves to the marine life to be tested. The angle of the transducer is vertically downward, and the transducer emits pulse sound waves into the accommodating space of the lower bracket at a beam angle of 7°.

[0009] A split beam transceiver, the split beam transceiver is located in the cavity of the buoy, and the split beam transceiver is used to receive the data collected by the transducer, that is, the pulse sound waves reflected from the marine organisms to be detected;

[0010] A wireless transmission bridge, the wireless transmission bridge being connected to the split-beam transceiver;

[0011] A server is connected to the wireless transmission bridge.

[0012] The server is used to perform algorithm calculations on the data, output target intensity results, and derive spectrum graphs based on the results.

[0013] In some embodiments, the split beam transducer and transceiver are of the EK80 type with a frequency of (70 kHz and 120 kHz), and the transducer uses broadband frequency acquisition, and the pulses emitted by the broadband echo sounder contain a series of frequencies, usually linear low frequency to high frequency modulation (FM) signals. The resulting broadband backscatter theoretically provides improved signal-to-noise ratio (SNR; dimensionless), range resolution (Δr; m), and wavelength-dependent echo characteristics, called frequency response. The latter may be used to improve target identification, thereby reducing the uncertainty of target abundance estimates.

[0014] In some embodiments, the device further comprises a camera, which is connected to the lower bracket and is used to take photos and videos (monitor) of the marine organisms to be detected in the accommodation space. The camera works underwater and uses a high-definition, high-quality camera.

[0015] In some embodiments, two cameras are provided, wherein one underwater camera is at the upper end of the lower bracket, the camera head of the camera looks downward to detect marine life, and another underwater camera is installed on the side of the lower bracket for horizontal angle detection.

[0016] In some embodiments, the buoy includes a body having a cavity therein, and corresponding openings are formed on the upper and lower sides of the body, and the openings are connected to the cavity.

[0017] In some embodiments, the wireless transmission bridge includes a wireless transmission bridge transmitter and a wireless transmission bridge receiver, the wireless transmission bridge transmitter is arranged on the upper bracket, the wireless transmission bridge receiver is connected to the wireless transmission bridge transmitter, and the wireless transmission bridge transmitter is connected to the split beam transceiver.

[0018] In some embodiments, the device further comprises a traction line, and the traction line is used to tow the marine organism to be detected.

[0019] In some embodiments, the device further includes a correction piece, which is disposed in the accommodating space of the lower bracket and is spherical.

[0020] In some embodiments, the calibration piece is made of tungsten carbide alloy.

[0021] In some implementations, the device further includes a client, and the client is connected to the server.

[0022] In some embodiments, the lower support includes a plurality of support rings and a plurality of support rods, the plurality of support rings are distributed in sequence along the vertical direction, the plurality of support rods are circumferentially connected around the plurality of support rings, and the buoy is connected to the support rods.

[0023] Another technical solution adopted by the present invention is:

[0024] A method for determining characteristics of marine biological acoustic targets, the method adopts the marine biological acoustic target characteristic determination device, comprising:

[0025] The echo intensity range of the transducer to marine life is adjusted, and the detection angle is preferably 2-10°; the acoustic data of marine life collected by the transducer is received by the split-beam transceiver, and transmitted to the server by the wireless transmission bridge, and the server calculates the acoustic target intensity of the marine life.

[0026] The target intensity calculation method is based on a variety of marine biological acoustic data. According to multiple experiments, the acoustic echo image records of various situations are verified, non-marine biological echo images and interference echoes are filtered out, and the single target intensity distribution map is derived. The calculation formula The target intensity of each marine organism is calculated, and the target intensity spectrum is derived through the monomer recognition technology. This spectrum is compared and analyzed with the current standard frequency response diagram and response characteristic curve diagram of marine organisms, and preferably compared with the data collected by the optical underwater camera for verification.

[0027] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0028] The marine biological acoustic target characteristic determination device provided by the present invention uses an algorithm to calculate the marine biological acoustic target intensity on the server, and draws a marine biological target intensity characteristic spectrum diagram based on the target intensity result, thereby ensuring the reliability of the front-end warning of marine biological invasion causing nuclear power cooling source disasters. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Attached Figure 1 It is a schematic diagram for limit value screening;

[0030] Attached Figure 2 This is a schematic diagram of angle screening;

[0031] Attached Figure 3 Spectrum diagram for individual marine organisms;

[0032] Attached Figure 4 Target intensity map for individual marine organisms;

[0033] Attached Figure 5 It is a spectrum characteristic diagram of group marine organisms;

[0034] Attached Figure 6 It is a spectrum characteristic diagram of a single marine organism;

[0035] Attached Figure 7 It is a structural diagram of the first viewing angle of the marine biological acoustic target characteristic determination device of the present invention;

[0036] Attached Figure 8 A structural diagram of the marine biological acoustic target characteristic determination device from a second viewing angle of the present invention;

[0037] Attached Fig. 9 It is a structural diagram of the upper bracket of the marine biological acoustic target characteristic determination device of the present invention;

[0038] Attached Fig.10 This is a structural diagram of the lower bracket of the marine biological acoustic target characteristic determination device of the present invention (without transducer and camera);

[0039] Attached Fig.11 It is a structural diagram of the lower support of the marine biological acoustic target characteristic determination device of the present invention;

[0040] Attached Fig.12 A structural diagram of a buoy of a marine biological acoustic target characteristic determination device of the present invention;

[0041] Attached Fig.13 A top view of the buoy of the marine biological acoustic target characteristic determination device of the present invention;

[0042] Attached Fig.14 A bottom view of the buoy of the marine biological acoustic target characteristic determination device of the present invention;

[0043] Attached Fig.15 The present invention is a flow chart of the marine biological acoustic target characteristic determination device.

[0044] In the above attached figure:

[0045] 1-buoy, 11-main body, 12-cover plate, 13-opening; 2-upper bracket; 3-lower bracket, 31-support ring, 32-support rod, 33-connecting plate, 34-counterweight block, 35-reinforcement plate, 36-support bottom plate, 37-shackle ring; 4-camera; 5-traction line; 6-handrail; 7-photovoltaic panel; 8-transducer; 9-marine life. DETAILED DESCRIPTION

[0046] The present invention will be further described below in conjunction with the embodiments shown in the accompanying drawings.

[0047] See also Figures 7 to 14 The marine biological acoustic target characteristic determination device shown includes an upper bracket 2, a lower bracket 3, a buoy 1, a transducer 8, a split-beam transceiver, a wireless transmission bridge, and a server.

[0048] The upper support 2 is located above the lower support 3. The middle of the lower support 3 has a storage space, and the marine life to be tested is located in the storage space. In some embodiments, the lower support 3 includes a plurality of support rings 31 and a plurality of support rods 32. The plurality of support rings 31 are distributed in sequence along the vertical direction. A gap is maintained between two adjacent support rings 31. The plurality of support rods 32 are connected around the circumference of the plurality of support rings 31. The buoy 1 is connected to the support rods 32. A reinforcing plate 35 is provided on the outer side and / or the inner side of the support ring 31 to enhance the overall strength. The support ring at the bottom is a counterweight block 34. The center line connecting the plurality of support rings 31 is located on the same vertical line, see Figure 7 The diameter of the support ring 31 at the bottom is greater than the diameter of the support ring 31 at the top, and the overall structure is more stable.

[0049] The buoy 1 is connected between the upper bracket 2 and the lower bracket 3, and the buoy 1 has a cavity. The transducer 8 is arranged in the accommodating space of the lower bracket 3 and is located below the buoy 1. The transducer 8 is used to transmit pulse sound waves to the marine life to be tested. The split beam transceiver is located in the cavity of the buoy 1. The split beam transceiver is used to receive the data collected by the transducer 8 (the pulse sound waves reflected from the marine life to be tested). The wireless transmission bridge is connected to the split beam transceiver, and the server is connected to the wireless transmission bridge. The wireless transmission bridge is used to transmit the original data collected by the split beam transceiver to the server. The server performs algorithm calculation on the data (can be processed by the Echoview software), outputs the target intensity result, draws the target intensity spectrum diagram according to the result, and finally compares the target intensity spectrum diagram with the existing marine life spectrum diagram for analysis and verification.

[0050] See also Figure 7 The buoy 1 includes a body 11, which has a cavity. The upper and lower sides of the body 11 are provided with corresponding openings 13. The upper and lower openings of the body 11 are connected with the cavity. A cover plate 12 is provided at the upper opening of the body 11. The opening can be closed by covering the cover plate 12, and the opening can be opened by removing the cover plate 12. In this example, a handrail 6 is provided on the upper side of the body 11.

[0051] See also Figure 7 The buoy 1 is fixed with four points, which makes the buoy 1 strong in wind and wave resistance. The buoy 1 is placed in a location with small wind and waves and in the direction of the main flow channel of the water intake channel, and the bracket has strong fixing strength; a four-point anchor block is used to connect the anchor chain ( Fig.11 In the figure, a shackle ring 37 is arranged on the connecting plate 33, and the shackle ring 37 is connected to the anchor chain to fix the posture of the buoy 1, which has strong wind and wave resistance and ensures that the sound waves emitted by the transducer 8 are stable; the buoy 1 is made of an integrated fiberglass reinforced plastic material and has strong waterproof performance.

[0052] In this example, the wireless transmission bridge uses a point-to-point long-distance transmission device with high transmission accuracy, no frame loss, strong and stable transmission timeliness.

[0053] In some embodiments, the wireless transmission bridge includes a wireless transmission bridge transmitter and a wireless transmission bridge receiver. The wireless transmission bridge transmitter is arranged on the upper bracket 2, the wireless transmission bridge transmitter is connected to the split beam transceiver, and the wireless transmission bridge receiver is connected to the wireless transmission bridge transmitter.

[0054] The device also includes a camera 4, which is connected to the lower bracket 3. The camera 4 is used to take photos and videos of the marine life to be tested in the accommodating space, monitor the movement trajectory of the marine life, so as to facilitate the analysis of the posture and autonomous breathing of the marine life. Two cameras 4 can be set up, and the shooting results are more accurate. The camera 4 of this example adopts a high-definition, high-quality underwater camera, combined with the underwater camera 4 to synchronously perform optical observation of the marine life, to ensure that the tested marine life survives in the frame and has good activity, and the subsequent acoustic and optical comparison leaves data to prove it.

[0055] The device also includes a traction line 5, which is used to connect to the marine life to be detected. For example, the traction line 5 is a No. 5 fishing line. The traction line 5 uses a three-point suspension method for the marine life, which ensures the biological activity of the marine life and ensures that the marine life is within the detection range of the transducer 8.

[0056] The device also includes a calibration piece, which is arranged at the bottom of the accommodation space of the lower bracket 3, and the standard ball is located directly below the marine organism (such as at a position of about 0.5m). The calibration piece is arranged, on the one hand, to eliminate the problem that the optical data of the marine organism cannot be found as a reference due to water quality reasons, and on the other hand, as a reference echo intensity to compare and analyze the echo intensity of the marine organism to verify the results. In some embodiments, the calibration piece is spherical, such as with a diameter of 38.1mm; the calibration piece is made of tungsten carbide alloy.

[0057] The device also includes a client, which is connected to the server and is used for displaying the result of the characteristic spectrum analysis of the marine biological target in real time.

[0058] The method for measuring the characteristics of marine biological acoustic targets using a marine biological acoustic target characteristic measuring device comprises the following steps:

[0059] 1. Adjust the monitoring range of the transducer 8, monitor the water depth, and adjust the traction line 5 to determine the detection effect of the split beam transducer 8; adjust the echo intensity range of the transducer 8 to the marine life, and the detection angle is in the range of 5-15° (preferably 7°); adjust the angle of the underwater optical camera 4, check the server optical image to confirm the detection range of the marine life; preferably adjust the standard ball to be suspended at a position about 0.5m directly below the marine life;

[0060] 2. After the test starts, the acoustic data from the transducer 8 to the marine organisms is received by the split beam transceiver and transmitted to the server by the wireless transmission bridge. The server processes the characteristics of the marine organism targets through an algorithm, including the following steps:

[0061] a. The server receives the split beam raw data and uses acoustic post-processing software to denoise and remove interference echoes. The denoising process extracts background noise by observing the echo image, selecting a typical blank background image as the background noise operation and calculating the average value of each ping, and then extracting it from the raw data. To remove interference echoes, the echo intensity table of specific ships, wind and waves, bubbles and debris is used to remove the interference echo list in the echo image.

[0062] b. After the echoes are pre-processed in step a), in order to understand the target marine biological target intensity, the echo image is divided into several water layers at 1m, and the marine biological target intensity of each water layer is analyzed; according to the definition of marine biological target intensity: the target intensity TS is a physical quantity that describes the object's ability to reflect sound waves, which is measured by the ratio of the echo intensity to the incident wave intensity, and is defined as:

[0063]

[0064] Where: Ir is the sound intensity of the echo 1m away from the target sound scattering center; I0 is the intensity of the incident sound wave.

[0065] c. Perform monomer identification based on the target intensity obtained in step b), analyze each ping in the split beam transducer 8 data, and first find the local maximum. If the local maximum is composed of multiple samples with the same value, use the first sample in this sequence; the pulse length must be between the set limit, the minimum standardized pulse length, and the maximum standardized pulse length. Figure 1 .

[0066] The beam compensation value shall not exceed the maximum beam compensation; the standard deviation of all sample angles (minor and major axes) within the pulse envelope shall not exceed the maximum allowed angle standard deviation. Figure 2 .

[0067] d. Relevant monomer target identification and export results through step c), the results are as follows Figure 3 :

[0068] e. Compare and analyze the result obtained in step d) with the video data of the underwater optical camera 4 to determine whether the characteristic spectrum characteristics of the target marine organisms are reliable.

[0069] 3. The server receives real-time live marine life video from the underwater optical camera 4;

[0070] 4. Comprehensively evaluate the results through the exported spectrum diagram and real-time video data.

[0071] The marine biological acoustic target characteristic determination device of this example uses a broadband frequency (between 120kHz and 200kHz) to measure marine biological monomers one by one by setting an acoustic transducer. The traditional narrowband echo sounder, such as EK60, emits a pulse containing a single-frequency sinusoidal continuous wave (CW) signal. In contrast, the pulse emitted by the wideband echo sounder contains a series of frequencies, usually linear low-frequency to high-frequency modulation (FM) signals. The resulting broadband backscattering theoretically provides an improved signal-to-noise ratio (SNR; dimensionless), distance resolution (Δr; m), and wavelength-related echo characteristics, called frequency response. The latter may be used to improve target identification, thereby reducing the uncertainty of target abundance estimation. Using compressed echoes, the signal-to-noise ratio (SNR refers to the ratio of the acoustic signal emitted by the acoustic wave transmission system to the noise. The larger the SNR, the less noise is generated) is higher, and the value of the TS of marine organisms in the frequency range of 120kHz to 200kHz is obtained, which can better show the overall trend and situation of the TS value changing with frequency.

[0072] The device in this example measures TS of marine organisms. The three-point suspension method can ensure that the marine organisms are facing the center of the transducer, which not only eliminates the situation where the data cannot be measured due to the marine organisms swimming to the corners of the cage, but also does not affect the free movement of the marine organisms in the cage. The traction line used has been calibrated before the experiment, and the echo can be ignored, which will not cause obvious errors in the measurement results.

[0073] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A marine biological acoustic target characteristic measuring device, characterized in that: The device comprises: An upper bracket and a lower bracket, wherein the upper bracket is located above the lower bracket, and a receiving space is provided in the middle of the lower bracket, and the marine organism to be tested is located in the receiving space; A buoy, wherein the buoy is connected between the upper bracket and the lower bracket, and the buoy has a cavity therein; A transducer, the transducer is arranged in the accommodation space of the lower bracket and is located below the buoy, and the transducer is used to emit pulse sound waves to the marine organisms to be detected; A split beam transceiver, the split beam transceiver is located in the cavity of the buoy, and the split beam transceiver is used to receive the data collected by the transducer; A wireless transmission bridge, the wireless transmission bridge being connected to the split-beam transceiver; A server is connected to the wireless transmission bridge.

2. The marine bioacoustic target characteristic measuring device according to claim 1, characterized in that: The device also includes a camera, which is connected to the lower bracket and is used to take photos and videos of the marine life to be detected in the accommodating space.

3. The marine bioacoustic target characteristic measuring device according to claim 1, characterized in that: The buoy comprises a main body, wherein the main body has a cavity, and corresponding openings are provided on the upper side and the lower side of the main body, and the openings are connected with the cavity.

4. The marine bioacoustic target characteristic measuring device according to claim 1, characterized in that: The wireless transmission bridge comprises a wireless transmission bridge transmitter and a wireless transmission bridge receiver. The wireless transmission bridge transmitter is arranged on the upper bracket, the wireless transmission bridge receiver is connected to the wireless transmission bridge transmitter, and the wireless transmission bridge transmitter is connected to the split beam transceiver.

5. The marine bioacoustic target characteristic measuring device according to claim 1, characterized in that: The device also includes a traction line, and the traction line is used to pull the marine organism to be detected.

6. The marine bioacoustic target characteristic measuring device according to claim 1, characterized in that: The device also includes a correction piece, which is arranged in the accommodating space of the lower bracket and is spherical.

7. The marine bioacoustic target characteristic measuring device according to claim 6, characterized in that: The correction piece is made of tungsten carbide alloy.

8. The marine bioacoustic target characteristic measuring device according to claim 1, characterized in that: The device also includes a client, and the client is connected to the server.

9. The marine bioacoustic target characteristic measuring device according to claim 1, characterized in that: The lower bracket includes a plurality of support rings and a plurality of support rods. The plurality of support rings are distributed in sequence along the vertical direction. The plurality of support rods are connected around the circumference of the plurality of support rings. The buoy is connected to the support rods.

10. A method for determining characteristics of marine biological acoustic targets, characterized in that: The method adopts the marine bioacoustic target characteristic determination device according to any one of claims 1 to 8, comprising: The transducer's echo intensity range for marine life is adjusted, and the acoustic data of marine life collected by the transducer is received by the split-beam transceiver, and transmitted to the server via the wireless transmission bridge. The server calculates the acoustic target intensity of the marine life.

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