Method and device for measuring and calculating freight volume of branch channels of multi-branch graded estuary channel

Abstract

The invention is suitable for the technical field of data processing, and provides a method and device for measuring and calculating the freight volume of each branch channel of a multi-branch graded estuary channel, and the method comprises the steps: obtaining the total freight volume of the multi-branch graded estuary channel; setting a typical cross section for each branched channel of the multi-branched graded estuary channel, and acquiring AIS data of a ship passing through each typical cross section; preprocessing the ship AIS data of each typical cross section; calculating the average ship loading rate of each branched channel according to the total freight volume of the multi-branched graded estuary channel and the processed ship AIS data of each typical cross section; and calculating the total freight volume of each branched channel according to the ship average loading rate of each branched channel and the processed ship AIS data of each typical cross section. According to the method, the freight volume of each branch channel of the multi-branch graded estuary channel can be accurately measured and calculated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of data processing, in particular to a cargo volume measurement method and device for each branch channel of a multi-branch hierarchical estuary channel. BACKGROUND

[0002] Due to the sudden expansion of the estuary area, the flow rate is reduced, and the water flow is affected by the tide, and a large amount of sediment is deposited in the water flow, which is easy to form a multi-branch hierarchical estuary channel with multiple branches. In order to vigorously promote river-sea intermodal transport, China has invested a large amount of funds to improve the conditions of the estuary channel, forming a multi-branch hierarchical estuary channel with different water depth conditions. Accurate cargo volume measurement of each branch channel of the multi-branch hierarchical estuary channel is of great significance to determine the scale of each branch channel regulation project.

[0003] Nowadays, due to the variety of ship types and different loading rates in the multi-branch hierarchical estuary channel, there is no direct cargo volume statistics. At present, there is a statistical estimation method for the total cargo volume of the estuary channel, which mainly combines data from multiple angles such as port throughput, ship flow and maritime reporting to estimate, but there is no statistical estimation method for the branch channel. If directly from the perspective of port throughput, based on the flow direction statistics of inland port throughput and the shortest path method to estimate the cargo volume, the influence of water depth conditions of the multi-branch hierarchical estuary channel on the selection of the ship route is not considered, so the accuracy of the cargo volume estimation result needs to be improved. SUMMARY

[0004] In view of the deficiencies in the prior art, the purpose of the present application is to provide a cargo volume measurement method and device for each branch channel of a multi-branch hierarchical estuary channel, to solve the problem of low accuracy of the existing statistical estimation method.

[0005] As a first aspect of the present application, a cargo volume measurement method for each branch channel of a multi-branch hierarchical estuary channel is provided, the method comprising the following steps:

[0006] Step S1: obtaining the total cargo volume of the multi-branch hierarchical estuary channel;

[0007] Step S2: setting a typical cross section for each branch channel of the multi-branch hierarchical estuary channel, and obtaining ship AIS data passing through each typical cross section; wherein the ship AIS data includes ship type, ship tonnage, ship heading and ship number of times;

[0008] Step S3: preprocessing the ship AIS data of each typical cross section to obtain the processed ship AIS data of each typical cross section;

[0009] Step S4: calculating the average loading rate of the ship of each branch channel according to the total cargo volume of the multi-branch hierarchical estuary channel and the processed ship AIS data of each typical cross section.

[0010] Step S5: Calculate the total cargo volume of each branch channel according to the average ship loading rate of each branch channel and the processed ship AIS data of each typical cross section.

[0011] As a further solution of the present invention: Step S1 further includes:

[0012] Calculate the total upstream cargo volume of the multi-branched and graded estuary waterway within a set time window and total downstream freight volume ; Among them, the total freight volume of upstream and total downstream freight volume The calculation formulas are as follows:

[0013] ;

[0014] ;

[0015] in, represents the total upstream cargo volume of the multi-branched and graded estuary waterway, represents the total downstream cargo volume of the multi-branched and graded estuary waterway, represents the total upstream freight volume of the jth type of cargo in the multi-branched and graded estuary waterway, represents the total downstream freight volume of the jth type of cargo in a multi-branched and graded estuary waterway, , Represents a collection of cargo types, including dry bulk, liquid bulk and containers.

[0016] As a further solution of the present invention: Step S2 further includes:

[0017] Obtain AIS data of ships passing through each typical cross section within a set time window, wherein the set time window satisfies ,in, To set the starting time of the time window, To set the deadline of the time window, At the moment when the mth ship passes through the typical cross section, the AIS data of the ships that meet the above conditions are extracted;

[0018] Among them, ship types include bulk cargo ships, liquid dangerous goods ships, and container ships;

[0019] First, different types of ships are divided into tonnages; since the ship tonnage is divided into nodes, the tonnage of each ship is determined by the following standards. Suppose the tonnage of the ship is , For all tonnages after division, less than The maximum ship tonnage of the value, For all the tonnage greater than The minimum ship tonnage value, if it meets

[0020] ;

[0021] The tonnage of the ship is determined as If it is greater than 50%, the tonnage of the ship is determined as ;

[0022] Among them, the number of times of different tonnage ships of different types passing through each typical cross section in the set time window is counted.

[0023] As a further scheme of the application: after step S2, further comprising:

[0024] According to the heading data, the upstream and downstream of the multi-branch hierarchical estuary channel are determined, and the measures of the two opposite headings of the multi-branch hierarchical estuary channel are respectively And If , the direction of the measure of the multi-branch hierarchical estuary channel is defined as downstream, The direction of the measure is defined as upstream, and vice versa; for the ship AIS data, if the heading measure L satisfies , it is defined that the heading of the ship is consistent with the direction of the measure, and the upstream and downstream of the ship are divided according to this standard.

[0025] As a further scheme of the application: in step S3, further comprising:

[0026] The non-cargo ships in the ship AIS data are removed, wherein the non-cargo ships include engineering ships, coast guard ships and fishing ships.

[0027] As a further scheme of the application: in step S4, further comprising:

[0028] For each branch channel of the multi-branch hierarchical estuary channel, the upstream and downstream average loading rates of the ships of different tonnage and different cargo types are introduced, and the least square method is used to calculate the average loading rate of the ships according to the following formula:

[0029] ;

[0030] ;

[0031] ;

[0032] ;

[0033] wherein, , represents a set of branch channel; , represents a set of ship tonnage; represents the total cargo volume of the jth cargo class in the ith branch channel, represents the average loading rate of the kth tonnage ship of the jth cargo class in the ith branch channel, represents the full load tonnage of the kth tonnage ship of the jth cargo class in the ith branch channel, represents the number of ships of the kth tonnage ship of the jth cargo class in the ith branch channel, represents the total cargo volume of the jth cargo class in the ith branch channel, represents the average loading rate of the kth tonnage ship of the jth cargo class in the ith branch channel, represents the full load tonnage of the kth tonnage ship of the jth cargo class in the ith branch channel, represents the number of ships of the kth tonnage ship of the jth cargo class in the ith branch channel;

[0034] the average loading rate of the ship is calculated, and samples are selected as training data, , represents a set of samples, numbered h, and is brought into the least squares method;

[0035] Let be the distance from the sample point to the fitting surface, i.e. the error is:

[0036] ;

[0037] Let D be the sum of squares, i.e. the sum of squares D is:

[0038] ;

[0039] According to the first derivative equal to 0 and the second derivative greater than or equal to 0, the unknown parameter is solved;

[0040] the first order partial derivative of is:

[0041] =0;

[0042] Finally, the result of the least squares method is derived as , i.e.

[0043]

[0044] wherein, represents the average number of times of the k-tonnage ship of the jth cargo class in the ith branch channel, represents the average total cargo quantity of the jth cargo class in the ith branch channel;

[0045] wherein, according to the average loading rate the calculation process is the same for the average loading rate .

[0046] As a further aspect of the present application, it further comprises:

[0047] The average loading rate and cannot exceed the maximum loading rate constant , and the specific limitation is as follows:

[0048]

[0049]

[0050] wherein, represents the average loading rate of the k-tonnage ship of the jth cargo class in the ith branch channel, represents the average loading rate of the k-tonnage ship of the jth cargo class in the ith branch channel, represents the maximum loading rate constant.

[0051] As a further aspect of the present application, in the step S5, it further comprises:

[0052] (1) First, the calculated average loading rate and are substituted into the following formula:

[0053] ;

[0054] ;

[0055] wherein, represents the total cargo quantity of the jth cargo class in the ith branch channel, represents the total cargo quantity of the jth cargo class in the ith branch channel;

[0056] (2) Then, the total cargo quantity of each cargo class in the branch channel and the total cargo quantity of each cargo class in the branch channel are summarized:

[0057] ;

[0058] ;

[0059] wherein, represents the total freight volume of the i-th branch channel in the upstream direction, represents the total freight volume of the i-th branch channel in the downstream direction.

[0060] As a second aspect of the present application, a device for measuring the freight volume of each branch channel of a multi-branch hierarchical estuary channel is provided, which is used to implement the method for measuring the freight volume of each branch channel of a multi-branch hierarchical estuary channel according to any one of the preceding aspects. The device for measuring the freight volume of each branch channel of a multi-branch hierarchical estuary channel comprises:

[0061] a first obtaining unit configured to obtain the total freight volume of the multi-branch hierarchical estuary channel;

[0062] a second obtaining unit configured to set a typical cross section for each branch channel of the multi-branch hierarchical estuary channel and obtain ship AIS data passing through each typical cross section, wherein the ship AIS data comprises ship type, ship tonnage, ship heading and ship number of times;

[0063] a processing unit configured to pre-process the ship AIS data of each typical cross section to obtain processed ship AIS data of each typical cross section;

[0064] a calculating unit configured to calculate the average loading rate of ships for each branch channel according to the total freight volume of the multi-branch hierarchical estuary channel and the processed ship AIS data of each typical cross section;

[0065] a measuring unit configured to measure the total freight volume of each branch channel according to the average loading rate of ships for each branch channel and the processed ship AIS data of each typical cross section.

[0066] As a third aspect of the present application, an electronic device is provided, which comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method according to any one of the preceding aspects when executing the computer program.

[0067] Compared with the prior art, the present application has the beneficial effect that the freight volume of each branch channel of a multi-branch hierarchical estuary channel can be accurately measured, which can save a large amount of funds for traffic industry statistics, and can provide data support for policy making, traffic planning, waterway freight analysis and the like, and has important significance for playing the advantages of river-sea combined transportation. BRIEF DESCRIPTION OF DRAWINGS

[0068] Figure 1A flow chart of a cargo volume measurement method of each branch channel of a multi-branch hierarchical estuary channel is provided.

[0069] Figure 2 A schematic diagram of the multi-branch hierarchical estuary channel is provided. DETAILED DESCRIPTION

[0070] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application.

[0071] The specific implementation of the present application will be described in detail below with reference to specific embodiments.

[0072] Embodiment one:

[0073] A certain estuary channel is taken as an object for implementation, as shown in the figure, wherein the water depth of the A branch channel is about 12 meters, the water depth of the B branch channel is about 6 meters, and a double-branch hierarchical estuary channel is formed. Figure 2

[0074] As shown in the figure, the present application embodiment provides a cargo volume measurement method of each branch channel of a multi-branch hierarchical estuary channel, and the method comprises the following steps: Figure 1

[0075] Step S1: obtaining the total cargo volume of the multi-branch hierarchical estuary channel;

[0076] Preferably, the step S1 further comprises:

[0077] calculating the total upbound cargo volume and the total downbound cargo volume of the multi-branch hierarchical estuary channel within a set time window; wherein the calculation formulae of the total upbound cargo volume and the total downbound cargo volume are as follows:

[0078] ;

[0079] ;

[0080] wherein, represents the total upbound cargo volume of the multi-branch hierarchical estuary channel, represents the total downbound cargo volume of the multi-branch hierarchical estuary channel, represents the total upbound cargo volume of the jth cargo class of the multi-branch hierarchical estuary channel, represents the total downbound cargo volume of the jth cargo class of the multi-branch hierarchical estuary channel, ​​​Representing a cargo class set, including dry bulk, liquid bulk and container.

[0081] It should be noted that the total cargo volume in step S1 is Figure 2 The total cargo volume and the cargo volume of each cargo class in the upstream and downstream of the inland river area, excluding the cargo volume of the A branch and B branch.

[0082] Step S2: setting a typical cross section for each branch channel of the multi-branch graded estuary channel, and obtaining ship AIS data passing through each typical cross section; wherein the ship AIS data includes ship type, ship name, ship IMO number, ship tonnage, ship heading and ship voyage;

[0083] Preferably, in step S2, further comprising:

[0084] Obtaining ship AIS data passing through each typical cross section within a set time window, wherein, to ensure that the ship is passing through the typical cross section within the set time window, the set time window satisfies , wherein, is the starting time of the set time window, is the end time of the set time window, both accurate to seconds, is the time when the mth ship passing through the typical cross section is screened out, and the ship AIS data satisfying the above conditions is extracted;

[0085] Wherein, the ship type includes bulk cargo ship, liquid dangerous goods ship and container ship;

[0086] Wherein, according to the General Design Specification for Sea Port (JTS 165-2013), the tonnage of different types of ships is divided, bulk cargo ships are divided into 1000, 2000, 3000, 5000, 10000, 15000, 20000, 30000, 40000, 50000, 70000, 100000, 120000, 150000, 200000, 250000, 300000 tonnage, liquid dangerous goods ships are divided into 1000, 2000, 3000, 5000, 10000, 20000, 30000, 50000, 80000, 100000, 120000, 150000, 250000, 300000 tonnage, and container ships are divided into 1000, 3000, 5000, 10000, 20000, 30000, 50000, 70000, 100000, 120000, 150000, 200000 tonnage; Since the tonnage of the ship is divided into nodes, the tonnage of each ship is determined by the following standard, and the tonnage of the ship is , is less than The maximum ship tonnage of the numerical value, The minimum ship tonnage of the numerical value, if the total tonnage of the ship is greater than The minimum ship tonnage of the numerical value, if the total tonnage of the ship is greater than

[0087] ;

[0088] The tonnage of the ship is determined as The tonnage of the ship is determined as The tonnage of the ship is determined as

[0089] The number of times of the different tonnage ships of different types passing through each typical cross section in the set time window is counted.

[0090] Preferably, the step S2 further comprises:

[0091] The upstream and downstream of the multi-branch hierarchical estuary channel are determined according to the heading data, and the measures of the two opposite headings of the multi-branch hierarchical estuary channel are respectively and If , the direction of the measure of the multi-branch hierarchical estuary channel is defined as downstream, and the direction of the measure is defined as upstream, and vice versa; for the ship AIS data, if the heading measure L satisfies , the heading of the ship is defined to be consistent with the direction of the measure, and the upstream and downstream of the ship are divided according to this standard.

[0092] In the embodiment of the present application, the 1000-ton class bulk cargo ship is taken as an example, and the heading measure of the ship is required to be consistent with the upstream direction of the measure, the tonnage of the ship is 1000 tons, and the type of the ship is bulk cargo ship.

[0093] Step S3: The ship AIS data of each typical cross section is preprocessed to obtain the processed ship AIS data of each typical cross section.

[0094] Preferably, the step S3 further comprises:

[0095] The non-cargo ships in the ship AIS data are removed, wherein the non-cargo ships include engineering ships, coast guard ships and fishing ships.

[0096] Step S4: According to the total cargo volume of the multi-branch hierarchical estuary channel and the processed ship AIS data of each typical cross section, the average loading rate of the ship of each branch channel is calculated.

[0097] Preferably, the step S4 further comprises:

[0098] For each branch channel of the multi-branch hierarchical estuary channel, the average loading rate of the ship is calculated by the least square method according to the following formula, and the average loading rate of the ship is divided into the uplink and downlink and divided into the cargo type and tonnage:

[0099] ;

[0100] ;

[0101] ;

[0102] ;

[0103] Wherein, , represents the branch channel set; , represents the ship tonnage set; represents the total cargo volume of the jth cargo type in the ith branch channel, represents the average loading rate of the kth tonnage ship of the jth cargo type passing through the ith branch channel, represents the full load tonnage of the kth tonnage ship of the jth cargo type passing through the ith branch channel, represents the number of times of the kth tonnage ship of the jth cargo type passing through the ith branch channel, represents the total cargo volume of the jth cargo type in the ith branch channel, represents the average loading rate of the kth tonnage ship of the jth cargo type passing through the ith branch channel, represents the full load tonnage of the kth tonnage ship of the jth cargo type passing through the ith branch channel, represents the number of times of the kth tonnage ship of the jth cargo type passing through the ith branch channel;

[0104] The average loading rate of the ship is calculated, and the sample is selected as the training data, , represents the sample set, numbered h, and is brought into the least square method;

[0105] Let be the distance from the sample point to the fitting surface, that is, the error is:

[0106] ;

[0107] Let D be the difference sum, that is, the difference sum D is:

[0108]

[0109] According to the first derivative being equal to 0 and the second derivative being greater than or equal to 0, the unknown parameters are solved

[0110] The first-order partial derivative is solved for

[0111] =0.

[0112] Finally, the following is derived That is, the least square method calculation result is:

[0113]

[0114] Wherein, Indicates the average number of times of the k-tonnage ship of the jth cargo class in the ith branch channel of the upstream, Indicates the average total cargo volume of the jth cargo class in the ith branch channel of the upstream.

[0115] Wherein, according to the calculation process of the average loading rate The average loading rate is calculated.

[0116] Specifically, it further includes:

[0117] Considering the influence of the water depth of the ship on the loading rate, a restriction condition needs to be introduced to limit the average loading rate And Cannot exceed the maximum loading rate constant The specific limiting method is as follows:

[0118]

[0119]

[0120] Wherein, Indicates the average loading rate of the k-tonnage ship of the jth cargo class in the ith branch channel of the upstream, Indicates the average loading rate of the k-tonnage ship of the jth cargo class in the ith branch channel of the downstream, Indicates the maximum loading rate constant.

[0121] In the embodiment of the application, according to the average water depth data of each branch channel of the multi-branch hierarchical estuary channel and the draft data of each cargo class and each tonnage ship under different loading rates, the maximum loading rate constant of different branch channels is summarized and brought into the model for fitting and calculating the average loading rate of the ship.​​​

[0122] Step S5: according to the average loading rate of the ships in each branch channel and the processed AIS data of the ships in each typical cross section, the total freight volume of each branch channel is calculated.

[0123] Preferably, the step S5 further comprises:

[0124] (1) first, the calculated average loading rate and are substituted into the following formula:

[0125] ;

[0126] ;

[0127] wherein, represents the total freight volume of the jth cargo class in the ith branch channel in the upstream direction, represents the total freight volume of the jth cargo class in the ith branch channel in the downstream direction.

[0128] In the embodiment of the present application, the tonnage of different ship types of bulk cargo ships in the upstream direction is multiplied by the corresponding average loading rate to obtain the upstream bulk cargo volume transported by the tonnage bulk cargo ship within a set time window. The same method is used for the downstream direction and other cargo classes of each tonnage ship. The upstream and downstream bulk cargo volume, liquid bulk cargo volume and container cargo volume are obtained by summarizing.

[0129] (2) the total freight volume of each cargo class in the upstream direction and the total freight volume of each cargo class in the downstream direction of different branch channels are summarized:

[0130] ;

[0131] ;

[0132] wherein, represents the total freight volume in the upstream direction of the ith branch channel, represents the total freight volume in the downstream direction of the ith branch channel.

[0133] According to the basic data in the example in embodiment one, the average loading rate of each tonnage ship of different cargo classes in the upstream and downstream directions through the A branch channel and the B branch channel is calculated, as shown in Tables 1-3. In this embodiment, it is calculated that the freight volume of the A branch channel is 115234 million tons and the freight volume of the B branch channel is 28286 million tons.

[0134] Table 1 (average loading rate of bulk cargo ships in the upstream and downstream directions through the A channel and the B channel)

[0135]

[0136] Table 2 (average loading rate of liquid dangerous goods ship when passing A channel and B channel in uplink and downlink)

[0137]

[0138] Table 3 (average loading rate of container ship when passing A channel and B channel in uplink and downlink)

[0139]

[0140] In summary, the application calculates the freight volume of each branch channel of a multi-branch hierarchical estuary channel in a data-driven manner, can more accurately measure the freight volume of each branch channel of a multi-branch hierarchical estuary channel, can save a large amount of funds for traffic industry statistical work, and can provide data support for policy making, traffic planning, waterway freight analysis and the like, and has important significance for playing the advantages of river-sea combined transportation.

[0141] Embodiment two:

[0142] The embodiment of the application provides a device for measuring freight volume of each branch channel of a multi-branch hierarchical estuary channel, which is used to realize the method for measuring freight volume of each branch channel of a multi-branch hierarchical estuary channel.

[0143] The first obtaining unit is configured to obtain total freight volume of the multi-branch hierarchical estuary channel.

[0144] The second obtaining unit is configured to set typical cross sections of each branch channel of the multi-branch hierarchical estuary channel, and obtain ship AIS data passing through each typical cross section, wherein the ship AIS data includes ship type, ship tonnage, ship heading and ship number of times.

[0145] The processing unit is configured to pre-process the ship AIS data of each typical cross section to obtain processed ship AIS data of each typical cross section.

[0146] The calculating unit is configured to calculate ship average loading rate of each branch channel according to the total freight volume of the multi-branch hierarchical estuary channel and the processed ship AIS data of each typical cross section.

[0147] The measuring unit is configured to measure total freight volume of each branch channel according to the ship average loading rate of each branch channel and the processed ship AIS data of each typical cross section.

[0148] Embodiment three:

[0149] The electronic device according to an embodiment of the present disclosure includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the method according to any one of the preceding embodiments when executing the computer program.

[0150] The above only describes the preferred embodiments of the present disclosure in detail, and does not limit the present disclosure. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

[0151] It should be understood that, although each step in the flowchart of each embodiment of the present disclosure is shown in sequence according to the arrow, these steps are not necessarily executed in sequence according to the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in each embodiment can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these sub-steps or stages is not necessarily sequential, but can be executed in rotation or alternation with at least part of other steps or sub-steps or stages of other steps.

[0152] It can be understood by those skilled in the art that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing related hardware, and the program can be stored in a non-volatile computer readable storage medium. When the program is executed, it can include the processes of the above-mentioned embodiments of each method. Any reference to memory, storage, database or other medium used in each embodiment provided by the present disclosure can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0153] Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments as described herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

Claims

1. A method for calculating the freight volume of each branch channel of a multi-branched estuary channel, characterized in that: The method for calculating the freight volume of each branch channel of the multi-branched graded estuary channel comprises the following steps: Step S1: Obtain the total cargo volume of multi-branched and graded estuary waterways; Step S2: setting a typical cross section for each branch channel of the multi-branched graded estuary channel, and obtaining AIS data of ships passing through each typical cross section; wherein the ship AIS data includes ship type, ship tonnage, ship heading, and ship number; Step S3: pre-processing the ship AIS data of each typical cross section to obtain processed ship AIS data of each typical cross section; Step S4: calculating the average loading rate of ships in each branch channel according to the total cargo volume of the multi-branched graded estuary channel and the processed ship AIS data of each typical cross section; Step S5: Calculate the total cargo volume of each branch channel according to the average ship loading rate of each branch channel and the processed ship AIS data of each typical cross section.

2. The method for calculating the freight volume of each branch channel of a multi-branched and graded estuary channel according to claim 1 is characterized in that: The step S1 further includes: Calculate the total upstream cargo volume of the multi-branched and graded estuary waterway within a set time window and total downstream freight volume ; Among them, the total freight volume of upstream and total downstream freight volume The calculation formulas are as follows: ； ； in, represents the total upstream cargo volume of the multi-branched and graded estuary waterway, represents the total downstream cargo volume of the multi-branched and graded estuary waterway, represents the total upstream freight volume of the jth type of cargo in the multi-branched and graded estuary waterway, represents the total downstream freight volume of the jth type of cargo in a multi-branched and graded estuary waterway, , Represents a collection of cargo types, including dry bulk, liquid bulk and containers.

3. The method for calculating the freight volume of each branch channel of a multi-branched and graded estuary channel according to claim 1 is characterized in that: The step S2 further includes: Obtain AIS data of ships passing through each typical cross section within a set time window, wherein the set time window meets the condition ,in, To set the starting time of the time window, To set the deadline of the time window, At the moment when the mth ship passes through the typical cross section, the AIS data of the ships that meet the above conditions are extracted; Among them, ship types include bulk cargo ships, liquid dangerous goods ships, and container ships; First, different types of ships are divided into tonnages; since the ship tonnage is divided into nodes, the tonnage of each ship is determined by the following standards. Suppose the tonnage of the ship is , For all tonnages after division, less than The maximum ship tonnage of the value, For all tonnages after division, The minimum ship tonnage of the value, if it meets ； The tonnage of the ship is determined to be Tonnage, if it is greater than 50%, the tonnage of the ship is determined to be Ton level; The number of ships of different tonnages among different types of ships passing through each typical cross section in the upward direction and the number of ships of different tonnages among different types of ships passing through each typical cross section in the downward direction within the set time window are counted.

4. The method for calculating the freight volume of each branch channel of a multi-branched and graded estuary channel according to claim 1 is characterized in that: After step S2, the method further includes: According to the heading data, the up and down directions of the multi-branched and graded estuary channel are determined. The two relative headings of the multi-branched and graded estuary channel are respectively and ,like , then define the multi-branched and graded estuary channel The direction of measurement is downward. The direction of measurement is upward, and vice versa; for the ship AIS data, if its heading measurement L satisfies , then define the ship's heading and The measurement direction remains consistent, and this standard is used to divide the upstream and downstream ships.

5. The method for calculating the freight volume of each branch channel of a multi-branched estuary channel according to claim 1 is characterized in that: The step S3 further includes: Eliminate non-cargo ships from the ship AIS data, wherein the non-cargo ships include engineering ships, patrol ships, and fishing vessels.

6. The method for calculating the freight volume of each branch channel of a multi-branched and graded estuary channel according to claim 1 is characterized in that: The step S4 further includes: For each branch channel of a multi-branched estuary, the average loading rate of upstream ships by cargo type and tonnage and the average loading rate of downstream ships by cargo type and tonnage are introduced. The average loading rate of ships is calculated using the least squares method according to the following formula: ； ； ； ； in, , Represents the collection of tributary channels; , Represents a collection of ship tonnages; represents the total upstream cargo volume of the jth type of cargo in the i-th branch channel, represents the average loading rate of the k-th tonnage ship of the j-th cargo category passing through the i-th branch channel, represents the fully loaded tonnage of the k-th tonnage ship of the j-th cargo category passing through the i-th branch channel, represents the number of k-ton ships of the j-th cargo category passing through the i-th branch channel. represents the total downstream cargo volume of the jth type of cargo in the i-th branch channel, represents the average loading rate of the k-th tonnage ship of the j-th cargo category passing through the i-th branch channel, represents the fully loaded tonnage of the k-th tonnage ship of the j-th cargo category passing through the i-th branch channel, Indicates the number of ships of k-th tonnage class and of j-th cargo type passing downstream in the i-th branch channel; Average loading rate of ships Perform calculations and select samples as training data. , Represents a sample set, numbered h, which is brought into the least squares method; set up For sample points The distance to the fitting surface, that is, the error for: ； Let D be the sum of squared differences, that is, the sum of squared differences D is: ； According to the first-order derivative being equal to 0 and the second-order derivative being greater than or equal to 0, find the unknown parameter ; right Find the first-order partial derivative: =0； Finally, it is derived , which is the result of least squares calculation: ； in, represents the average number of k-ton ships of the j-th cargo category passing through the i-th branch channel. represents the average total upstream cargo volume of the jth cargo type in the i-th branch channel; Among them, according to the above average loading rate The calculation process of the average loading rate is the same as that of Perform calculations.

7. The method for calculating the freight volume of each branch channel of a multi-branched and graded estuary channel according to claim 6 is characterized in that: Also includes: Limit average load rate and The maximum loading rate constant cannot be exceeded , the specific limitation methods are as follows: ； ； in, represents the average loading rate of the k-th tonnage ship of the j-th cargo category passing through the i-th branch channel, represents the average loading rate of the k-th tonnage ship of the j-th cargo category passing through the i-th branch channel, Represents the maximum loading rate constant.

8. The method for calculating the cargo volume of each branch channel of a multi-branched estuary channel according to claim 6 is characterized in that: The step S5 further includes: (1) First, calculate the average loading rate and Substitute the following formula: ； ； in, represents the total upstream cargo volume of the jth type of cargo in the i-th branch channel, represents the total downstream cargo volume of the jth cargo type in the i-th branch channel; (2) Summarize the total upstream cargo volume and the total downstream cargo volume of each cargo category in different branch waterways: ； ； in, represents the total upstream cargo volume of the i-th branch channel, represents the total downstream cargo volume of the i-th branch channel.

9. A device for calculating the cargo volume of each branch channel of a multi-branched and graded estuary waterway, used to implement the method for calculating the cargo volume of each branch channel of a multi-branched and graded estuary waterway according to any one of claims 1 to 8, characterized in that: The cargo volume calculation device for each branch channel of the multi-branched graded estuary channel includes: The first acquisition unit is used to obtain the total cargo volume of the multi-branched and graded estuary waterway; The second acquisition unit is configured to set a typical cross section for each branch channel of the multi-branched and graded estuary channel, and acquire AIS data of ships passing through each typical cross section; wherein the ship AIS data includes ship type, ship tonnage, ship heading, and ship number; a processing unit, configured to pre-process the ship AIS data of each typical cross section to obtain processed ship AIS data of each typical cross section; a calculation unit, configured to calculate an average ship loading rate of each branch channel according to the total cargo volume of the multi-branched graded estuary channel and the processed ship AIS data of each typical cross section; The calculation unit is used to calculate the total cargo volume of each branch channel according to the average loading rate of ships in each branch channel and the processed ship AIS data of each typical cross-section.

10. An electronic device, characterized in that: The method comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method according to any one of claims 1 to 8 when executing the computer program.

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