A method for automatically dispatching a double-track ship lock

Abstract

The present invention provides an automatic scheduling method for a double-track ship lock, and relates to the technical field of double-track ship lock management. The present invention acquires ship data within a certain range that is the same as the passage direction of the double-track ship lock in real time through an automatic identification system, and generates accurate ship arrival time data. Through the integration of these data, the problem that the arrival time of the ship cannot be accurately predicted in the prior art can be effectively solved. By monitoring the water level height, water flow velocity, meteorological data and other information upstream and downstream of the ship lock, the load condition of each ship lock is accurately evaluated in combination with the maximum carrying capacity of the ship lock. By constructing a priority model based on the arrival time of the ship, the draft depth and environmental factors, all ship scheduling nodes are reasonably grouped, so that the load of each group of ship clusters matches the maximum carrying capacity of the ship lock. By calculating the average priority of each ship cluster, ships are allowed to pass according to the sorting results.

Description

Technical Field

[0001] The invention relates to the technical field of double-track ship lock management, and in particular to an automatic dispatching method for a double-track ship lock. Background Art

[0002] With the rapid growth of the global shipping industry, the pressure on water transportation is increasing, especially in the lock area of ​​the transportation hub. The passage efficiency of ships is directly related to the operation efficiency of the entire shipping system. As an advanced water conservancy facility, the double-track lock can control the passage of multiple ships simultaneously or alternately to improve the passage capacity of the waterway. Usually, the double-track lock will arrange multiple lock channels according to different directions to optimize the scheduling and management of ship passage. However, with the increasing number of ships and increasingly complex ship types, how to effectively schedule ships to pass through the double-track lock has become a major challenge in shipping management.

[0003] Most of the current scheduling methods for double-track ship locks rely on manual experience or simple rules of "first come, first served". Such methods can basically meet the needs when the ship flow is small or the traffic conditions are relatively simple, but the efficiency of traditional scheduling methods is greatly reduced under high-density ship traffic, complex hydrological conditions or severe weather conditions. Existing scheduling methods usually find it difficult to consider the specific characteristics of ships such as draft, ship size, speed, etc., as well as real-time external conditions such as water level changes, weather, water flow, etc., which leads to frequent congestion and low utilization of locks during passage. In addition, when double-track ship locks control ships passing in multiple directions, they usually focus on fixed directions. The scheduling method fails to fully utilize the maximum carrying capacity of the lock and lacks a flexible adjustment mechanism.

[0004] The current scheduling methods for double-track ship locks have several obvious shortcomings. First, the existing scheduling methods lack accurate predictions of the arrival time and passage order of ships, and fail to combine real-time data for scheduling optimization. Second, the traditional methods are slow to respond to changes in the external environment and cannot dynamically adjust the scheduling strategy according to actual conditions. Finally, the existing scheduling methods fail to make full use of modern intelligent algorithms for group scheduling of ships, especially in the lock channel in one direction, the passage order and resource allocation of ships fail to achieve optimal optimization. Therefore, there is an urgent need for an intelligent scheduling method to solve the efficiency problem in the scheduling of single-direction double-track ship locks, reduce ship waiting time and improve the lock capacity.

[0005] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0006] The object of the present invention is to provide a method for automatic dispatching of a double-track ship lock to solve the problems raised in the above-mentioned background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for automatically dispatching a double-track ship lock, the specific steps comprising:

[0009] Step 1: Use the ship's automatic identification system to identify the ship that is traveling in the same direction as the double-track ship lock. The navigation information and ship data of the ship within the nautical mile range, the ship data including the length, width and draft data of the ship, the navigation information of the ship including the position information and speed data of the ship, the ship is numbered, and the arrival time data of the ship is generated according to the position information and speed data of the ship;

[0010] Step 2: Monitor the water level and water flow velocity data upstream and downstream of each lock in the double-track ship lock to be dispatched, monitor the meteorological data of the area where the double-track ship lock is located, the meteorological data includes wind speed and rainfall data, and obtain the maximum carrying capacity data of each lock;

[0011] Step 3: Build a basic priority model based on the arrival time data of the ship, the draft data of the ship and the meteorological data of the area where the lock is located, generate the dispatch priority of each ship, correct the maximum carrying capacity data of the lock through the water level and water flow velocity data upstream and downstream of the lock, and obtain the reference load data of each lock;

[0012] Step 4: Take each ship as a dispatching node, build an undirected graph network, place each dispatching node in an independent community, use the community detection algorithm to group all dispatching nodes, generate multiple groups of ship clusters, and ensure that the combination of ships corresponding to all dispatching nodes in each ship cluster meets the capacity limit of the lock;

[0013] Step 5: Calculate the average priority of each ship cluster, sort the ship clusters according to the average priority, and allow the ships in each ship cluster to pass through the lock according to the sorting results.

[0014] Furthermore, the method for generating the arrival time data of the ship according to the position information and speed data of the ship is:

[0015] According to the location information of the ship and the location information of the double-track ship lock, the distance between the ship and the double-track ship lock is calculated based on the formula:

[0016] in, For the number The distance between the ship and the double-track lock, is the radius of the Earth in nautical miles, They are numbered The longitude and latitude data of the ship, are the longitude and latitude data of the location of the double-track ship lock, in degrees. They are numbered The first intermediate coefficient and the second intermediate coefficient between the ship and the double-track lock, Indicates the ship's number;

[0017] The ship's arrival time data is generated by the distance between the ship and the double-track ship lock and the ship's speed data. The formula is:

[0018] in, Respectively indicate the number The arrival time and speed data of the ship, Indicates the distance threshold to the double-track ship lock.

[0019] Furthermore, the basic priority model is constructed to generate the scheduling priority of each ship based on the following formula:

[0020] in, They are numbered The scheduling priority and draft of the ships, They are the wind speed data and rainfall data of the area where the double-track ship lock is located. are wind speed threshold and rainfall threshold respectively, are wind speed weight coefficient, rainfall weight coefficient and time weight coefficient respectively. ,and .

[0021] Further, the maximum load capacity data of the ship lock is the maximum length and maximum width data of the ship lock in the double-track ship lock, the reference load data of the ship lock includes reference length and reference width data, and the logic for generating the reference load data of the ship lock is:

[0022] in, Respectively represent The reference length and reference width data of each lock, Respectively represent The maximum length and width of the locks, Respectively represent The maximum water level difference and maximum water flow velocity allowed by the design of each ship lock are Respectively represent The water level upstream and downstream of each lock, Respectively represent The flow rates upstream and downstream of each lock, Indicates the number of the lock in the double-track lock that needs to be dispatched.

[0023] Furthermore, an undirected graph network is constructed and the method for grouping all scheduling nodes is as follows:

[0024] Take each ship as a scheduling node, add arrival time data to each scheduling node as the attribute of the scheduling node, and build an undirected graph. According to the arrival time data between each scheduling node, add edges to the undirected graph to form an undirected graph network.

[0025] Place each scheduling node in an independent community. For each scheduling node in the undirected graph network, move it to the community where all its neighboring nodes are located one by one, and calculate the change rate of the average scheduling priority of the entire community if each move occurs.

[0026] Move the scheduling node to the neighbor community with the smallest change rate of the average scheduling priority, and calculate the total length and total width of the ships corresponding to all scheduling nodes in the entire community. When the total length exceeds the minimum reference length, or the total width exceeds the minimum reference width data, move the node to the neighbor community with the second smallest change rate of the average value, and so on, until the community to which the scheduling node belongs is determined;

[0027] Repeat the scheduling of each scheduling node until the community affiliation of all scheduling nodes no longer changes.

[0028] Furthermore, the neighbor nodes are nodes directly connected by edges in an undirected graph network, that is, if two nodes are connected by a direct edge, they are considered to be neighbor nodes. According to the arrival time data between each scheduling node, the specific logic for adding edges in the undirected graph is:

[0029] Calculate the difference and average of the arrival time data corresponding to any two scheduling nodes. If the difference is greater than 0.2 times the average value, no edge is generated between the two scheduling nodes in the undirected graph. If it is less than or equal to 0.2 times the average value, an edge is generated between the two scheduling nodes in the undirected graph. The formula is:

[0030] like , then the number is The ship and number are No edges are generated between the scheduling nodes corresponding to the ships;

[0031] like , then the number is The ship and number are Generate edges between the scheduling nodes corresponding to the ships;

[0032] Respectively indicate the number and number Arrival time data of ships, Indicates the ship's number. Indicates the difference between two vessel numbers.

[0033] Furthermore, the minimum reference length is calculated as follows:

[0034] , the calculation method of the minimum reference width is: in, Respectively represent the minimum reference length and minimum width data, Respectively represent The reference length and reference width data of each lock, Indicates the number of the lock in the double-track lock that needs to be dispatched. Indicates the total number of locks in the double-track lock that need to be dispatched.

[0035] Furthermore, the calculation method of the scheduling priority average change rate is specifically as follows:

[0036] Calculate the average dispatching priority values ​​corresponding to all dispatching nodes in the original community before the move, and calculate the average dispatching priority value of the entire community after the move if the move occurs. Subtract the average dispatching priority value before the move from the average dispatching priority value after the move, and compare the difference with the average dispatching priority value before the move to obtain the rate of change of the average dispatching priority value of the entire community if the move occurs.

[0037] Furthermore, when calculating the average priority of each ship cluster, the average value is calculated as the average priority data of the ship cluster based on the scheduling priority of each scheduling node corresponding to the ship in the cluster, and all ship clusters are sorted from high to low according to the average priority. The locks in the double-track lock work in parallel, and multiple clusters are assigned to different locks at one time. The cluster with the highest average priority is assigned first, and the cluster with the second highest priority is assigned to other idle locks. After each lock completes the passage of the current cluster, it immediately starts the passage of the next group of clusters. When multiple locks are idle at the same time, the ship clusters are assigned to the idle locks according to the average priority.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] The present invention uses an automatic identification system to obtain in real time ship data within a certain range that is the same as the passage direction of the double-track ship lock, including the length, width, draft, speed and position information of the ship, and generates accurate ship arrival time data. Through the integration of these data, the problem that the arrival time of the ship cannot be accurately predicted in the prior art can be effectively solved, thereby improving the accuracy and rationality of scheduling. By monitoring the water level height, water flow speed and meteorological data upstream and downstream of the ship lock, the external environment and passage conditions of the double-track ship lock can be dynamically grasped, and combined with the maximum carrying capacity of the ship lock, the load condition of each ship lock can be accurately evaluated, and the complex external environmental changes can be flexibly responded to, especially when the hydrological conditions and meteorological conditions are complex and changeable, the resource utilization rate of the ship lock can be effectively improved;

[0040] The present invention improves the ship traffic scheduling from the traditional "first come, first served" rule to dynamic priority management based on actual conditions by constructing a priority model based on ship arrival time, draft depth and environmental factors. All ship scheduling nodes can be reasonably grouped through an undirected graph network and a community detection algorithm, so that the load of each group of ship clusters matches the maximum carrying capacity of the lock, thereby solving the problems of chaotic ship scheduling order and insufficient utilization of lock resources in the prior art. By calculating the average priority of each ship cluster and passing ships according to the sorting results, the traffic efficiency of the lock can be improved to the maximum extent, the waiting time of ships can be reduced, and at the same time, the traffic capacity of the double-track lock can be fully utilized, especially during peak hours when ships are densely populated, so as to achieve the goal of efficient and safe passage of multiple ships at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the overall method flow of the present invention. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0043] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0044] Example

[0045] See also Figure 1 , the present invention provides a technical solution:

[0046] A method for automatically dispatching a double-track ship lock, the specific steps comprising:

[0047] Step 1: Use the ship's automatic identification system to identify the ship that is traveling in the same direction as the double-track ship lock. The navigation information and ship's own data of the ship within the nautical mile range, the ship's own data including the ship's length, width and draft depth data, the navigation information of the ship including the ship's position information and speed data, the ship is numbered, and the ship's arrival time data is generated based on the ship's position information and speed data.

[0048] The automatic identification system acquires and broadcasts the dynamic and static data of the ship in real time through special equipment installed on the ship. The automatic identification system relies on the GPS positioning system and other sensors on the ship to automatically collect the ship's real-time location information, speed, heading and other navigation information. These data are broadcast to other nearby ships, shore-based receiving stations or satellites at fixed intervals via radio signals to ensure that ships can recognize and communicate with each other.

[0049] The ship's own data is manually input by the crew or operators into the ship's automatic identification system. This data is saved in the ship's automatic identification system and sent together with dynamic information when the ship broadcasts. The ship's GPS system and sensors can continuously monitor the dynamic changes of the ship, and the ship's own data is the input information. Through the wireless network, shore-based receiving stations or other ships can receive this information within a certain range, and then grasp the navigation status and basic characteristics of the ship to ensure safe and efficient ship management.

[0050] A double-track ship lock refers to a waterway facility with multiple ship locks, which allows multiple ships to pass through simultaneously or alternately. It can be divided into multiple directions of passage. One direction is usually controlled by several fixed ship locks. The scheduling method of this embodiment is aimed at the ship locks that control the passage of ships in one direction. The same passage direction means that these ships are all heading in the same direction. For example, if a double-track ship lock has five ship locks for entering the port, then the ships with the same passage direction are all ships entering the port. The ship lock scheduling is to schedule the passage of the five ship locks. The ships within a certain range refer to the ships within a certain geographical area, which refers to the ships close to the ship locks and preparing to pass through the ship locks.

[0051] The value range is The monitoring range of the waters before and after the lock is usually 1-2 nautical miles. Within this range, ships need to slow down, prepare to enter or leave the lock, and follow the corresponding dispatch and command. The waters near the lock are the bottleneck of the waterway, and the ships are slow and require precise control. The range of 1-2 nautical miles ensures that the status of ships entering the lock area can be understood in advance to prevent congestion and collision. The efficiency of entering and exiting the lock is related to the queues and waiting for ships to pass. Setting the dynamic range of ship management to 1-2 nautical miles helps ports or locks to arrange dispatch in advance, reasonably allocate the order of passage, and avoid ship accumulation or excessive waiting.

[0052] In this embodiment, the method for generating the arrival time data of the ship according to the position information and speed data of the ship is:

[0053] The location information of the ship and the location information of the double-track ship lock are both coordinates composed of longitude and latitude. The distance between the ship and the double-track ship lock is calculated based on the following formula:

[0054] in, For the number The distance between the ship and the double-track lock, is the radius of the Earth in nautical miles, They are numbered The longitude and latitude data of the ship, are the longitude and latitude data of the location of the double-track ship lock, in degrees. They are numbered The first intermediate coefficient and the second intermediate coefficient between the ship and the double-track lock, Indicates the ship's number.

[0055] The geographical distance between the ship and the double-track ship lock is calculated based on the longitude and latitude information and the curvature of the earth, using the Haversine formula. This embodiment calculates the straight-line distance between the ship and the double-track ship lock through the longitude and latitude information of the ship and the double-track ship lock. Taking into account the spherical characteristics of the earth, the straight-line distance between the two points is calculated by the longitude and latitude difference, rather than just the distance on the plane. Because the earth is a sphere, the longitude and latitude difference between the two points is calculated first, and then the spherical distance between the two points is calculated through trigonometric functions. It can be used to calculate the arrival time of the ship, determine the route, and avoid navigation risks.

[0056] The ship's arrival time data is generated by the distance between the ship and the double-track ship lock and the ship's speed data. The formula is:

[0057] in, Respectively indicate the number The arrival time and speed data of the ship, Indicates the distance threshold to the double-track ship lock.

[0058] The estimated time for a ship to arrive at the double-track lock, i.e., the arrival time data, is calculated by combining the distance between the ship and the lock and the ship's speed. At the same time, a distance threshold is introduced, indicating that the arrival time is no longer calculated within a certain distance. If the distance between the ship and the double-track lock is less than the threshold, it is considered that the ship has entered a shorter range and may be approaching the lock. Therefore, the arrival time is set to 0. At this time, it is assumed that the ship is ready to enter the lock, and further calculation of the arrival time is no longer meaningful.

[0059] The introduction of distance thresholds can simplify calculations in certain short-distance situations. When a ship is very close to a lock, accurate time calculations are no longer meaningful because the ship may be slowing down, adjusting, stationary, or waiting to enter the lock. In this case, by setting the arrival time to 0, the complexity of the scheduling system can be simplified and it can be indicated that the ship has "almost" arrived at the lock. When a ship is very close to a lock, the speed and position change frequently, and the system may constantly recalculate and update the arrival time. After introducing the distance threshold, this unnecessary frequent update is avoided, improving the calculation efficiency.

[0060] When a ship approaches a lock, the actual sailing time will be affected by many factors, such as the waiting time at the lock, traffic conditions in the channel, slowing of the ship, etc. When the distance is very close, the estimated arrival time is no longer an absolute reference indicator. Therefore, the distance threshold is equivalent to a "near field range", that is, when the ship is close enough to the lock, it is no longer necessary to accurately calculate the arrival time, and the ship is directly regarded as having arrived.

[0061] This embodiment combines the distance between the ship and the double-track ship lock and the speed of the ship, and simplifies the complex situation when approaching the ship lock by using the distance threshold. For most ships, especially larger cargo ships and passenger ships, a certain deceleration distance is required when approaching a port or lock. 0.5 nautical miles is usually a sufficient distance for the ship to safely decelerate and prepare to enter the lock. When the ship is within 0.5 nautical miles of the lock, the ship usually enters the preparation stage and will slow down or adjust its course. The 0.5 nautical mile threshold can be applied to various types of ships, including large cargo ships and small fishing boats or yachts. Setting the distance threshold to 0.5 is relatively flexible and can meet the operational needs of different ships when approaching the lock.

[0062] Step 2: Monitor the water level and water flow velocity data upstream and downstream of each lock in the double-track ship lock to be dispatched, monitor the meteorological data of the area where the double-track ship lock is located, the meteorological data includes wind speed and rainfall data, and obtain the maximum carrying capacity data of each lock.

[0063] In this embodiment, the maximum load-bearing capacity data of the ship lock are the maximum length and maximum width data of the ship lock in the double-track ship lock, and the maximum length and maximum width are usually design parameters of the ship lock, which can be obtained from the design drawings and specifications of the ship lock, and provided by the ship lock management agency or design unit.

[0064] The upstream and downstream water level refers to the height of the water surface upstream and downstream of the lock. This is an important indicator that determines whether the ship can pass through the lock safely. The lock usually balances the water difference between upstream and downstream by adjusting the water level to ensure that the ship can pass smoothly. The water level difference between upstream and downstream of the lock needs to be within a controllable range, otherwise the ship cannot enter and exit the lock. The upstream and downstream water flow velocity refers to the flow velocity of the water body upstream and downstream of the lock. This determines the flow characteristics of the water and the flow resistance that the ship may encounter when passing through the lock. Strong water flow velocity may affect the operation and safety of the ship, especially when berthing and entering and exiting the lock. The water level height is obtained by real-time measurement of water level monitors installed upstream and downstream of the lock. The upstream refers to the starting point or source of the water flow, close to the source of the river or the side where the water body flows into the lock. The downstream refers to the outlet or end point of the water flow, the direction of the water flow.

[0065] Meteorological data can be monitored by automatic weather stations installed near the locks. Wind speed refers to the speed of air flow in the area where the locks are located. Wind speed has an important impact on the berthing, navigation and entry and exit of ships, especially large ships. Excessive wind speed may cause deviation and affect safe operation. Rainfall refers to the amount of precipitation in the area, which affects water level changes and lock operations. Heavy rainfall may cause the upstream water level to rise rapidly, increase the complexity of lock operations, and may even cause flood risks.

[0066] Step 3: Build a basic priority model based on the arrival time data of the ship, the draft data of the ship and the meteorological data of the area where the lock is located, generate the scheduling priority of each ship, correct the maximum carrying capacity data of the lock through the water level and water flow velocity data upstream and downstream of the lock, and obtain the reference load data of each lock.

[0067] In this embodiment, the basic priority model is constructed to generate the scheduling priority of each ship based on the formula:

[0068] in, They are numbered The scheduling priority and draft of the ships, They are the wind speed data and rainfall data of the area where the double-track ship lock is located. are wind speed threshold and rainfall threshold respectively, are wind speed weight coefficient, rainfall weight coefficient and time weight coefficient respectively. ,and ,The larger scheduling priority is, the higher priority the ship enjoys when passing through the waterway.

[0069] or When , it means that the rainfall or wind speed is large and the weather is bad, and the draft depth is the core factor of the ship scheduling priority, especially in bad weather. Because ships with large draft are more stable in the face of bad environment, their scheduling priority increases when the wind speed or rainfall exceeds the threshold. By directly putting the draft depth as a multiplier into the scheduling priority calculation, it means that ships with large draft have a natural priority advantage.

[0070] and When the wind speed is 20 knots, it means that both the rainfall and wind speed are small and the weather is good. In good weather, the scheduling priority formula becomes the inverse of the draft depth. Ships with a small draft will be more likely to be arranged to pass first. This is because under good environmental conditions, ships with shallower drafts can pass through the channel more easily and more efficiently. In general, 20 knots is considered a common safe wind speed limit for commercial ships. The threshold for rainfall is usually more flexible, depending on the intensity and duration of the rainfall. Generally speaking, rainfall exceeding 10 mm in a short period of time may affect visibility and navigation safety.

[0071] When wind speed and rainfall exceed the threshold, it means that the weather conditions have an increased impact on navigation, especially for shallow draft ships. In this case, ships with greater draft have greater stability, thus increasing To adjust the priority of ships with large draft, the impact of wind speed on scheduling priority is proportional to the wind speed weight coefficient, which means that the greater the wind speed, the more advantages ships with large draft have, because they are less susceptible to wind. The impact of rainfall is proportional to the rainfall weight coefficient. In heavy rain, ships with large draft are relatively more stable, so their priority increases. Ships with large draft will get higher priority due to their better stability. At this time, the scheduling system has to rely more on the physical characteristics of the ship to ensure the safety and smoothness of the waterway, and introduces and It serves as a magnifying factor to increase the priority of ships with large draft, ensuring that they have priority passage in bad weather and reducing the risk of potential accidents.

[0072] In good weather, when wind speed and rainfall are below the safety threshold, the impact of environmental factors on scheduling priorities is ignored. At this time, ships with smaller drafts are given priority because they are easier to pass quickly under good weather conditions, while ships with larger drafts do not have a significant advantage in good weather, and the scheduling system pays more attention to the passage efficiency of ships. Therefore, ships with smaller drafts are given priority to pass, which can improve the passage efficiency of the channel, because ships with smaller drafts are faster in good weather and are more flexible in turning and maneuvering.

[0073] Regardless of the weather conditions, the impact of time on priority cannot be ignored. As time goes by, the priority of a ship gradually decreases. This time decay mechanism encourages the scheduling system not to let some ships wait too long and not get a chance to pass. This ensures the dynamic balance of the scheduling system so that ships will not be neglected for a long time due to other high-priority factors. In order to prevent ships from being backlogged due to long waiting times, a time decay item is added. ,As time goes by, the priority of each ship will gradually decrease, encouraging the scheduling system to handle ships with longer waiting times as early as possible.

[0074] The scheduling priority adopts the form of a piecewise function. Different decisions need to be made when facing different weather conditions. In bad weather, when the wind speed and rainfall exceed the threshold, the scheduling system will give priority to the physical properties of the ship, especially the draft depth. This is because ships with large drafts are more stable and less risky in bad weather, so they are given priority for passage. In good weather, wind speed and rainfall have less impact on ships, and the scheduling strategy focuses more on passage efficiency. In this case, ships with small drafts have advantages in speed and flexibility, so they are given priority to pass to improve overall efficiency. This segmented design ensures that the scheduling system can flexibly adjust priorities under different weather conditions, thereby taking into account both safety and efficiency.

[0075] In bad weather conditions, the draft is directly multiplied into the formula, because ships with a large draft are less susceptible to external environmental influences in the face of strong winds and heavy rains due to their low center of gravity and greater stability. Therefore, ships with a large draft have a higher probability of passing through first under such conditions. In good weather conditions, the inverse of the draft is used to calculate the priority. This is because under stable conditions, ships with a smaller draft are more maneuverable and easier to pass quickly. Therefore, ships with a smaller draft are given a higher priority, which can improve the efficiency of passage, because ships with shallower drafts are more likely to pass through the channel safely and quickly without interference from the external environment.

[0076] When adjusting priorities in severe weather, the impact of wind speed and rainfall on priority is achieved through linear weighting, because the impact of wind speed and rainfall on ships is cumulative - the stronger the wind and the more rain there is, the more we want to give priority to ships with larger drafts, because they are more resistant to these external factors.

[0077] Time decay term is an exponential decay function, used to ensure that ships with long waiting times are not ignored. Exponential decay is chosen over linear decay because the exponential function has a faster initial decay characteristic. This can quickly reduce the priority in the early stages to ensure that ships are not stranded for a long time. By adjusting the time decay coefficient, the impact of the ship's waiting time on the priority can be controlled.

[0078] is the weight of the time factor, reflecting the impact of waiting time on priority. is the weight of the impact of wind speed on priority, reflecting the impact of wind speed on ship stability and trafficability. is the weight of the impact of rainfall on priority, reflecting the adverse impact of rainfall on ship traffic. Time factor is usually a key factor in ship scheduling. If a ship waits for a long time, the priority should drop quickly so that it can be scheduled in time. Therefore, the impact of time is considered to be the most important. In severe weather conditions, wind speed usually has a more direct impact on ships than rainfall. Wind speed directly affects the maneuverability and stability of the ship, so its weight is higher than rainfall. Although rainfall affects visibility and navigation conditions, it is usually smaller than the impact of wind speed. It ensures that the sum of all weights is 1, so that the impact of each factor can be relatively compared within the same range, facilitating dynamic adjustment of the dispatching system. The wind speed threshold and rainfall threshold are obtained from the clear provisions of regulations on such thresholds to ensure navigation safety.

[0079] Furthermore, the reference load data of the ship lock includes reference length and reference width data, and the logic for generating the reference load data of the ship lock is:

[0080] in, Respectively represent The reference length and reference width data of each lock, Respectively represent The maximum length and width of the locks, Respectively represent The maximum water level difference and maximum water flow velocity allowed by the design of each ship lock are Respectively represent The water level upstream and downstream of each lock, Respectively represent The flow rates upstream and downstream of each lock, Indicates the number of the lock in the double-track lock that needs to be dispatched.

[0081] Refers to the maximum length of ships that the lock can accommodate under ideal conditions. When the water level difference between upstream and downstream increases, the total length of ships that the lock can safely accommodate will decrease. This is because the larger the water level difference, the more serious the turbulence of the water flow may be. Ships need more buffer space when passing through the lock, thus reducing the effective available length interval. When the water level difference between upstream and downstream increases, the kinetic energy of the water flow and the disturbance of the water will not increase in a linear manner, but will increase in an accelerated manner. For example, if the water level difference doubles, the kinetic energy of the water flow may increase more than double, because the speed and turbulence intensity of the water flow will be more affected. Through the square term, the model reflects the nonlinear growth of this water level difference effect. The change in water level difference has a much greater impact on the safety of ship passage than a linear function can express, so the use of the square term can better describe this accelerated change. When the water level difference is close to zero, the reference length is close to the maximum length, and when the water level difference increases, the reference length gradually decreases to avoid the lock from operating under unsafe conditions. When the water level difference is very small, the value of the square term is very small, indicating that the water level difference has little effect on the length of the lock. As the water level difference increases, the square term increases rapidly and the length of the lock is greatly reduced. This design is to ensure that the lock can still maintain safe operation under extreme water level differences and prevent accidents caused by water turbulence.

[0082] When the velocity difference between upstream and downstream increases, the total width of the ship that the lock can safely accommodate will decrease. The greater the velocity difference, the stronger the interference of the water flow, making it more difficult for ships passing through the lock to maintain stability. Therefore, it is necessary to reduce the effective width to ensure the safe passage of ships. The exponential decay function This reflects the nonlinearity of this effect: when the velocity difference is small, the impact on the reference width is small; when the velocity difference increases, the reference width will decrease rapidly. The impact of the velocity difference on the ship passing through the lock is not linear. Even if the velocity difference gradually increases from zero, the disturbance and impact of the fluid on the ship does not increase at a uniform rate, but shows a change that is first slower and then faster. The exponential function can well express this effect. When the velocity difference is small, the impact is relatively small. As the velocity difference increases, the impact shows an accelerated growth. The exponential decay function can smoothly describe this nonlinear process, that is, under a small velocity difference, the lock width will not decrease significantly; but when the velocity difference reaches a certain threshold, the reference width will shrink sharply to ensure safety under extreme conditions.

[0083] Step 4: Take each ship as a dispatching node, construct an undirected graph network, place each dispatching node in an independent community, use the community detection algorithm to group all dispatching nodes, generate multiple groups of ship clusters, and ensure that the combination of ships corresponding to all dispatching nodes in each ship cluster meets the capacity limit of the lock.

[0084] In this embodiment, an undirected graph network is constructed and a method for grouping all scheduling nodes is as follows:

[0085] Take each ship as a scheduling node, add arrival time data to each scheduling node as the attribute of the scheduling node, and build an undirected graph. According to the arrival time data between each scheduling node, add edges to the undirected graph to form an undirected graph network.

[0086] Place each scheduling node in an independent community. For each scheduling node in the undirected graph network, move it to the community where all its neighboring nodes are located one by one, and calculate the change rate of the average scheduling priority of the entire community if each move occurs.

[0087] Move the scheduling node to the neighbor community with the smallest change rate of the average scheduling priority, and calculate the total length and total width of the ships corresponding to all scheduling nodes in the entire community. When the total length exceeds the minimum reference length, or the total width exceeds the minimum reference width data, move the node to the neighbor community with the second smallest change rate of the average value, and so on, until the community to which the scheduling node belongs is determined;

[0088] Repeat the scheduling of each scheduling node until the community affiliation of all scheduling nodes no longer changes, and the ships in each community are regarded as a ship cluster.

[0089] The process of building an undirected graph network and grouping the scheduling nodes is essentially an algorithm based on community detection and optimization, which is used to optimize the scheduling priority allocation of ships and ensure the efficiency and rationality of the lock scheduling process. Each ship is regarded as a scheduling node. Each scheduling node has an important attribute, which is the arrival time data of the ship. The nodes in the undirected graph are these scheduling nodes, and the edges are added according to the relationship between the scheduling nodes (for example, the similarity or difference of the arrival time of the ship). The relative difference in arrival time between each pair of scheduling nodes determines whether to add an edge. The construction of the undirected graph allows us to understand the relationship between ships in the time dimension from a global perspective. The closer the ships are (in time), the denser the edges between the nodes.

[0090] Each dispatching node is placed in an independent community. In the initial construction phase of the undirected graph, each ship (dispatching node) is regarded as an independent community. This initial state is equivalent to each node being in a separate dispatching unit. By initially placing all nodes in independent communities, it is ensured that the subsequent community merging process is data-driven and follows the optimal dispatching strategy. For each dispatching node, try to move it to the community where its neighboring nodes are located. A neighboring node is a node that is connected to the dispatching node by an edge in an undirected graph. The goal of this step is to optimize the ownership of dispatching nodes through community reorganization. After each move, calculate the rate of change of the dispatching priority of the community where the node is located. This step is the key. By calculating the change in community priority brought about by each move, it is measured whether the node movement helps to optimize the entire dispatching process. This is the core indicator for judging the effect of the move, which means that if the node is moved to a new community, whether the dispatching efficiency or other priority-related indicators have improved or deteriorated. The smaller the rate of change, the more stable or better the dispatching system as a whole.

[0091] According to the principle of minimizing the rate of change, the scheduling node is moved to the community with the smallest rate of change in priority. In other words, try to move the node to a community that makes the entire scheduling system change the least and is the most stable. After moving the node to the new community, it is necessary to count the total length and total width of all scheduling nodes in the community. If the total length of the ships in the community exceeds the minimum reference length allowed by the lock, or the total width of the ships in the community exceeds the minimum reference width, it means that this community cannot accommodate more ships. In this case, move the node to the community with the second smallest rate of change in priority and try again. This process will continue until a community that meets the length and width restrictions is found.

[0092] After each adjustment of the community affiliation of the node, repeat the process until the community affiliation of all scheduling nodes in the entire undirected graph no longer changes. In other words, all nodes have been assigned to the optimal community, and the scheduling priority change rate can no longer be further optimized by moving. When the community affiliation of all scheduling nodes is fixed, the entire algorithm ends, and the generated community grouping is the final scheduling result of the ship. This embodiment minimizes the priority change during the ship lock scheduling process by gradually optimizing the community affiliation of the scheduling nodes (ships). At the same time, considering the physical limitations of the length and width of the ship, by gradually moving the nodes, the fluctuation of the scheduling priority is reduced, and the stability and rationality of the scheduling plan are ensured. The total length and total width of the ship are considered to ensure that the total number of ships in the community does not exceed the physical capacity of the lock.

[0093] Furthermore, the neighbor nodes are nodes directly connected by edges in an undirected graph network, that is, if two nodes are connected by a direct edge, they are considered to be neighbor nodes. According to the arrival time data between each scheduling node, the specific logic for adding edges in the undirected graph is:

[0094] Calculate the difference and average of the arrival time data corresponding to any two scheduling nodes. If the difference is greater than 0.2 times the average value, no edge is generated between the two scheduling nodes in the undirected graph. If it is less than or equal to 0.2 times the average value, an edge is generated between the two scheduling nodes in the undirected graph. The formula is:

[0095] like , then the number is The ship and number are No edges are generated between the scheduling nodes corresponding to the ships;

[0096] like , then the number is The ship and number are Generate edges between the scheduling nodes corresponding to the ships;

[0097] Respectively indicate the number and number Arrival time data of ships, Indicates the ship's number. Indicates the difference between two vessel numbers.

[0098] The establishment of edges between nodes is based on the similarity of arrival time. Scheduling nodes of ships that are close in time are considered to be likely to influence or depend on each other, so connecting edges can help reflect this relationship in the graph. By setting a threshold (0.2 times the average value), nodes with similar arrival times can be effectively captured. Generally, the scheduling and passage of ships are time-sensitive, and similar arrival times mean that these ships may need to pass through the locks within the same time interval, so their scheduling priorities affect each other.

[0099] Selecting 0.2 times as the threshold also helps ensure that the calculation of arrival time differences is not overly affected by extreme cases (such as arrival times that are particularly close or far apart). By setting a moderate ratio value, it can more robustly handle groups of ships with different time distributions and avoid failure in certain extreme cases. Selecting 0.2 times the average value can avoid generating too many edges in the undirected graph and prevent the structure of the graph from being too complex. If the number of edges is too large, community division and subsequent optimization will become computationally complex. By setting this threshold, the number of edges can be effectively reduced, thereby maintaining the sparsity of the graph and improving computational efficiency.

[0100] By calculating the arrival time difference and average value between scheduling nodes and adopting a strategy of 0.2 times the average value as the connection threshold, an undirected graph reflecting the ship scheduling relationship can be effectively established. The core logic of this strategy is to emphasize the importance of time similarity, while controlling the sparsity and structural rationality of the graph, thus laying a good foundation for subsequent scheduling priority optimization. This method not only improves the efficiency of the algorithm, but also ensures the flexibility and adaptability of the scheduling system in practical applications.

[0101] In this embodiment, the minimum reference length is calculated as follows:

[0102] , the calculation method of the minimum reference width is:

[0103] in, Respectively represent the minimum reference length and minimum width data, Respectively represent The reference length and reference width data of each lock, Indicates the number of the lock in the double-track lock that needs to be dispatched. Indicates the total number of locks in the double-track lock that need to be dispatched.

[0104] When dispatching ships to pass through double-track locks, the size of the ship must meet the physical limitations of the locks. Since the reference length and width of different locks may vary, it is necessary to ensure that all dispatched ships can pass through the smallest lock during the dispatch process. By selecting the minimum reference length and minimum reference width among all locks, it is ensured that the dispatched ships can pass through all locks smoothly during the entire process. If the dispatched ship exceeds the minimum lock size limit, it will be unable to pass through certain locks, which will affect the feasibility and safety of the dispatch. In the double-track lock system, different locks may have different sizes and capacities due to structure, design and other reasons. By selecting the minimum size, the dispatch system can be adapted to all locks, and the dispatch system can be operated with a unified standard regardless of how the lock structure changes.

[0105] In this embodiment, the method for calculating the scheduling priority average change rate is specifically as follows:

[0106] Calculate the average dispatching priority values ​​corresponding to all dispatching nodes in the original community before the move, and calculate the average dispatching priority value of the entire community after the move if the move occurs. Subtract the average dispatching priority value before the move from the average dispatching priority value after the move, and compare the difference with the average dispatching priority value before the move to obtain the rate of change of the average dispatching priority value of the entire community if the move occurs.

[0107] By calculating the rate of change of the average dispatch priority before and after the move, it is possible to intuitively determine whether the move has a positive or negative impact on the overall dispatch priority of the community. If the rate of change is positive, it means that the average dispatch priority of the community has increased after the move, and the dispatch efficiency may be improved; if the rate of change is negative, it means that the average dispatch priority after the move has decreased, and the dispatch plan may need to be further adjusted. The effect of moving certain nodes (ships) on the overall dispatch optimization can be quantified and evaluated, thereby providing a basis for optimizing the dispatch strategy.

[0108] The calculation process of the change rate of the average scheduling priority can be summarized as follows: first calculate the average scheduling priority before and after the move, get the difference, and then divide the difference by the average scheduling priority before the move to get the change rate. This calculation method can help determine the impact of node movement on the overall scheduling efficiency of the community and provide data support for subsequent scheduling optimization.

[0109] Step 5: Calculate the average priority of each ship cluster, sort the ship clusters according to the average priority, and allow the ships in each ship cluster to pass through the lock according to the sorting results.

[0110] In this embodiment, when calculating the average priority of each ship cluster, the average value is calculated according to the scheduling priority of the ship corresponding to each scheduling node in the cluster as the average priority data of the ship cluster, and all ship clusters are sorted from high to low according to the average priority. The locks in the double-track lock work in parallel, and multiple clusters are allocated to different locks at one time. The cluster with the high average priority is allocated first, and the cluster with the second highest priority is allocated to other idle locks. After each lock completes the passage of the current cluster, it immediately starts the passage of the next group of clusters. When multiple locks are idle at the same time, the ship clusters are allocated to the idle locks according to the average priority.

[0111] Each ship cluster is composed of multiple ships, and each ship has a separate scheduling priority, which reflects the scheduling urgency or importance of the ship. For a ship cluster, the average priority of the cluster must be calculated first as the overall priority of the cluster. After calculating the average priority of all ship clusters, all clusters are sorted from high to low according to the average priority. The sorting result can clearly show which ship clusters have higher priorities and need to pass through the locks first, and which clusters have lower priorities and can pass through later. The higher the average priority of the cluster, the more priority it has. This can ensure that more urgent or important ships can pass through the locks first, reducing the overall waiting time.

[0112] A double-track lock means that multiple locks can be operated in parallel at the same time. At this time, multiple locks handle different ship clusters at the same time. The parallel operation of the double-track lock can improve the overall traffic efficiency. According to the sorting results, the ship cluster with the highest priority will be assigned to a certain idle lock first. When multiple locks are idle, the cluster with the second highest priority will be assigned to other idle locks. For example, if there are three idle locks, the first three clusters will be assigned to these three locks according to their priority. This can maximize the utilization of the locks, avoid the locks being idle, and ensure that the high-priority cluster can pass first.

[0113] When a lock completes the passage of the current cluster, the next cluster of ships to be passed is immediately assigned to the lock to ensure the continuous operation of the lock without idleness or waiting. This dynamic allocation mechanism keeps the utilization rate of the lock at a high level, and can flexibly adjust subsequent scheduling according to the actual completion time of each lock. If multiple locks complete the task at the same time and become idle, the next group of ship clusters will still be allocated according to priority. The cluster with the highest priority is assigned to a certain idle lock, and the cluster with the second highest priority is assigned to other idle locks.

[0114] The high-priority ship clusters reduce their waiting time for passage through the priority allocation mechanism. Through parallel allocation and dynamic allocation, all locks can be kept in working condition as much as possible to reduce the idle time of the locks. Through priority sorting and dynamic scheduling, the system can flexibly respond to the scheduling needs of different ship clusters and ensure the optimization of the overall process.

[0115] Assume that there are 3 locks and 5 ship clusters, and the average priority of the ship clusters is ranked from high to low as Cluster A, Cluster B, Cluster C, Cluster D and Cluster E. In the initial state, all 3 locks are idle, then Cluster A, Cluster B and Cluster C will be assigned to the 3 locks respectively. When the lock where Cluster A is located completes the task first, the next Cluster D with the highest priority will be immediately assigned to the idle lock. If two locks are idle at the same time, the system will assign Cluster D and Cluster E to the two idle locks in order of priority. If some ship clusters have the same priority, the cluster with a larger total number of ships will be given priority.

[0116] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0117] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. Those skilled in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0118] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0119] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A method for automatic dispatching of a double-track ship lock, characterized in that: The specific steps include: Step 1: Use the ship's automatic identification system to identify the ship that is traveling in the same direction as the double-track ship lock. The navigation information and ship data of the ship within the nautical mile range, the ship data including the length, width and draft data of the ship, the navigation information of the ship including the position information and speed data of the ship, the ship is numbered, and the arrival time data of the ship is generated according to the position information and speed data of the ship; Step 2: Monitor the water level and water flow velocity data upstream and downstream of each lock in the double-track ship lock to be dispatched, monitor the meteorological data of the area where the double-track ship lock is located, the meteorological data includes wind speed and rainfall data, and obtain the maximum carrying capacity data of each lock; Step 3: Build a basic priority model based on the arrival time data of the ship, the draft data of the ship and the meteorological data of the area where the lock is located, generate the dispatch priority of each ship, correct the maximum carrying capacity data of the lock through the water level and water flow velocity data upstream and downstream of the lock, and obtain the reference load data of each lock; Step 4: Take each ship as a dispatching node, build an undirected graph network, place each dispatching node in an independent community, use the community detection algorithm to group all dispatching nodes, generate multiple groups of ship clusters, and ensure that the combination of ships corresponding to all dispatching nodes in each ship cluster meets the capacity limit of the lock; Step 5: Calculate the average priority of each ship cluster, sort the ship clusters according to the average priority, and allow the ships in each ship cluster to pass through the lock according to the sorting result; The maximum load capacity data of the ship lock is the maximum length and maximum width data of the ship lock in the double-track ship lock. The reference load data of the ship lock includes reference length and reference width data. The logic for generating the reference load data of the ship lock is: in, Respectively represent The reference length and reference width data of each lock, Respectively represent The maximum length and width of the locks, Respectively represent The maximum water level difference and maximum water flow velocity allowed by the design of each ship lock are Respectively represent The water level upstream and downstream of each lock, Respectively represent The flow velocity upstream and downstream of each lock, Indicates the number of the lock in the double-track lock that needs to be dispatched; The method for constructing an undirected graph network and grouping all scheduling nodes is as follows: Take each ship as a scheduling node, add arrival time data to each scheduling node as the attribute of the scheduling node, and build an undirected graph. According to the arrival time data between each scheduling node, add edges to the undirected graph to form an undirected graph network. Place each scheduling node in an independent community. For each scheduling node in the undirected graph network, move it to the community where all its neighboring nodes are located one by one, and calculate the change rate of the average scheduling priority of the entire community if each move occurs. Move the scheduling node to the neighbor community with the smallest change rate of the average scheduling priority, and calculate the total length and total width of the ships corresponding to all scheduling nodes in the entire community. When the total length exceeds the minimum reference length, or the total width exceeds the minimum reference width data, move the node to the neighbor community with the second smallest change rate of the average value, and so on, until the community to which the scheduling node belongs is determined; Repeat the scheduling of each scheduling node until the community affiliation of all scheduling nodes no longer changes.

2. The automatic dispatching method of a double-track ship lock according to claim 1, characterized in that: The method for generating the arrival time data of a ship based on the position information and speed data of the ship is: According to the location information of the ship and the location information of the double-track ship lock, the distance between the ship and the double-track ship lock is calculated based on the formula: in, For the number The distance between the ship and the double-track lock, is the radius of the Earth in nautical miles, They are numbered The longitude and latitude data of the ship, are the longitude and latitude data of the location of the double-track ship lock, in degrees. Number The first intermediate coefficient and the second intermediate coefficient between the ship and the double-track lock, Indicates the ship's number; The ship's arrival time data is generated by the distance between the ship and the double-track ship lock and the ship's speed data. The formula is: in, Respectively indicate the number The arrival time and speed data of the ship, Indicates the distance threshold to the double-track ship lock.

3. The automatic dispatching method of a double-track ship lock according to claim 2, characterized in that: The specific formula for constructing the basic priority model to generate the scheduling priority of each ship is: in, They are numbered The scheduling priority and draft of the ships, They are the wind speed data and rainfall data of the area where the double-track ship lock is located. are wind speed threshold and rainfall threshold respectively, are wind speed weight coefficient, rainfall weight coefficient and time weight coefficient respectively. ,and .

4. The automatic dispatching method of a double-track ship lock according to claim 1, characterized in that: The neighbor nodes are nodes directly connected by edges in an undirected graph network. That is, if two nodes are connected by a direct edge, they are considered to be neighbor nodes. According to the arrival time data between each scheduling node, the specific logic for adding edges in the undirected graph is as follows: Calculate the difference and average of the arrival time data corresponding to any two scheduling nodes. If the difference is greater than 0.2 times the average value, no edge is generated between the two scheduling nodes in the undirected graph. If it is less than or equal to 0.2 times the average value, an edge is generated between the two scheduling nodes in the undirected graph. The formula is: like , then the number is The ship and number are No edges are generated between the scheduling nodes corresponding to the ships; like , then the number is The ship and number are Generate edges between the scheduling nodes corresponding to the ships; Respectively indicate the number and number Arrival time data of ships, Indicates the ship's number. Indicates the difference between two vessel numbers.

5. The automatic dispatching method of a double-track ship lock according to claim 4, characterized in that: The calculation method of the minimum reference length is: The calculation method of the minimum reference width is: in, Respectively represent the minimum reference length and minimum width data, Respectively represent The reference length and reference width data of each lock, Indicates the number of the lock in the double-track lock that needs to be dispatched. Indicates the total number of locks in the double-track lock that need to be dispatched.

6. The automatic dispatching method of a double-track ship lock according to claim 1, characterized in that: The calculation method of the scheduling priority average change rate is as follows: Calculate the average dispatching priority values ​​corresponding to all dispatching nodes in the original community before the move, and calculate the average dispatching priority value of the entire community after the move if the move occurs. Subtract the average dispatching priority value before the move from the average dispatching priority value after the move, and compare the difference with the average dispatching priority value before the move to obtain the rate of change of the average dispatching priority value of the entire community if the move occurs.

7. The automatic dispatching method of a double-track ship lock according to claim 1, characterized in that: When calculating the average priority of each ship cluster, the average value is calculated as the average priority data of the ship cluster based on the scheduling priority of each scheduling node corresponding to the ship in the cluster. All ship clusters are sorted from high to low according to the average priority. The locks in the double-track lock work in parallel. Multiple clusters are assigned to different locks at one time. Clusters with high average priority are assigned first, and clusters with the second highest priority are assigned to other idle locks. After each lock completes the passage of the current cluster, it immediately starts the passage of the next group of clusters. When multiple locks are idle at the same time, ship clusters are assigned to idle locks according to the average priority.

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