A method for predicting the capacity of a ship lock to open for cargo transport

Abstract

The application discloses a kind of shiplock opening lock cargo transport capacity prediction method, including according to the kind division of shiplock in opening lock applicable scene and determining interannual reference time, dividing calculation period and statistics period average opening lock time, based on Lorenz curve and trapezoidal method to determine the uniformity in year, effective opening lock time is calculated in combination with interannual reference time and uniformity in year, determine ship navigation parameter and calculate one-way single pass lock time and daily average one-way pass lock frequency, in combination with ship load parameter and traffic volume coefficient to calculate opening lock one-way annual cargo transport capacity, by introducing gini number quantification opening lock time distribution uniformity in year and fixed value range, effectively overcome the problem of ignoring distribution non-uniformity in year and unstable variation coefficient index in prior art, with the advantages that time distribution uniformity can be reasonably quantified, physical meaning is clear, calculation result is stable and compatible with multiple shiplock scenes.

Description

Technical Field

[0001] This application relates to the field of water conservancy engineering, and more specifically, to a method for predicting the cargo throughput capacity of a lock when it is open. Background Technology

[0002] As a core navigation facility in inland waterway networks, the operational efficiency of locks directly determines the smoothness and economy of regional water transport logistics. Lock opening, as an efficient passage mode, allows vessels to pass directly through the lock chamber at a constant speed when the upstream and downstream water level difference is within a safe threshold, avoiding the traditional filling and emptying process. This significantly shortens passage time and improves navigation efficiency, and has been widely used in estuarine tidal locks and water resource allocation hub locks. However, the available time for lock opening is constrained by multiple dynamic factors such as hydrological fluctuations, tidal periodic changes, and water resource scheduling plans, exhibiting significant uneven time distribution on both interannual and intra-annual scales. Simply using the multi-year average lock opening time in capacity prediction, while ignoring the uneven intra-annual time distribution, will lead to prediction results that deviate significantly from the actual available capacity, resulting in an overestimation of the lock's cargo transport potential. Early prediction methods relied solely on interannual average time parameters, completely neglecting intra-annual distribution differences, leading to significant calculation biases and affecting the scientific nature of waterway planning and transportation resource allocation.

[0003] In existing technologies, Chinese invention patent ZL202311578512.1 proposes a method for correcting the water allocation unevenness coefficient based on the coefficient of variation, used to adjust the gate opening time to reflect the unevenness within the year. However, this method has fundamental flaws: as a quantification index of uniformity, the coefficient of variation lacks fixed upper and lower bounds in its numerical range, leading to ambiguous physical meaning and difficulty in intuitive interpretation; simultaneously, this coefficient is highly sensitive to the length of hydrological data sequences and extreme values, resulting in drastic fluctuations and insufficient reliability under short-sequence data conditions. Furthermore, this method is only applicable to water resource scheduling lock scenarios and cannot cover the special operating conditions of estuarine tidal locks, severely limiting its applicability. Therefore, current technology urgently needs a prediction method that can accurately quantify the uniformity of time allocation, has clear physical meaning, provides stable calculation results, and is compatible with multiple lock scenarios to address the shortcomings of existing technologies in terms of coverage, index stability, and engineering applicability.

[0004] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0005] The purpose of this application is to provide a method for predicting the cargo throughput capacity of a lock when it is open. This method has the advantages of being able to reasonably quantify the uniformity of time allocation, having clear physical meaning, providing stable calculation results, and being compatible with multiple lock scenarios.

[0006] This application provides a method for predicting the cargo throughput capacity of a ship lock during lock opening, the technical solution of which is as follows: The method includes: S1. Classify ship locks according to the applicable scenarios for their opening and determine the corresponding annual benchmark time; S2. Divide the calculation period according to the change cycle of the lock opening time, and calculate the average opening time of each period under the annual benchmark condition of the lock and arrange them in ascending order; S3. Calculate the Gini coefficient of the lock opening time distribution based on the Lorenz curve and trapezoidal method, and determine the annual uniformity based on the Gini coefficient; S4. Calculate the effective opening time of the lock based on the interannual reference time and the annual uniformity of the lock. S5. Determine the navigation parameters of ships passing through the lock based on the lock level and representative ship type, and calculate the one-way single-pass time of the representative ship type and the average daily one-way pass number of the lock. S6. Calculate the annual one-way freight throughput capacity of the lock when it is open, taking into account the ship loading coefficient and the freight volume imbalance coefficient. In S6, the annual freight throughput capacity of the gate in one direction is opened. The calculation formula is: , in, This represents the average number of one-way passages per day at the lock. This refers to the average load capacity per lock passage (in tons). This refers to the ship's loading coefficient. This is the coefficient for imbalance in transport volume.

[0007] Furthermore, this application also proposes that, in S1, the lock is divided into estuary tidal zone lock and water resource allocation lock according to the lock opening scenario; the estuary tidal zone lock uses the average value of the measured lock opening time over many years as the interannual reference time, and the water resource allocation lock determines the interannual reference time according to the scheduling or design hydrological conditions.

[0008] Furthermore, this application also proposes that water resource allocation type locks are divided into water resource scheduling type locks and runoff regulation type locks; the water resource scheduling type locks obtain the interannual reference time by subtracting the annual average number of days of water regulation from the annual number of days of water passage, while the runoff regulation type locks use the annual average number of days of lock opening under the design hydrological conditions as the interannual reference time.

[0009] Furthermore, this application also proposes that, in S2, the opening time of the tidal lock is subject to a semi-monthly tide, and the opening time of the water resource allocation lock is subject to a monthly or ten-day period.

[0010] Furthermore, this application also proposes that, in S3, the Gini coefficient is calculated using the trapezoidal method, with the following formula: , , , in, Gini coefficient; To calculate the total number of time periods; This refers to the total time the gate is open. For the front The cumulative value of the gate opening time for each period; The index for the cumulative count over the time period. ,when hour, ; For traversing indices within a single time period; For the first The gate opening time within a specific time period; The formula for calculating the annual uniformity is: ; in, The value represents the uniformity within the year, and its range is fixed at [0,1]. The larger the value, the more evenly the opening time of the gate is distributed within the year.

[0011] Furthermore, this application also proposes that, in S4, the formula for calculating the effective opening time of the lock is as follows: , in, For the effective gate opening time; As the interannual base time; The annual uniformity.

[0012] Furthermore, this application also proposes that, in S5, the safe distance and speed of ships are determined based on the lock level and representative ship type, and the one-way single-pass time is calculated; the one-way single-pass time... The calculation formula is: , in, The safe passage length of a ship through the lock, in units of This includes the ship's physical length and safety clearance, i.e. ; The speed of a ship, in units of .

[0013] Furthermore, this application also proposes that, in S5, the average daily number of one-way passages is calculated based on the daily gate operation time; the average daily number of one-way passages... The average number of one-way passages per day depends on the daily operating hours of the gate and the one-way passage time. The calculation formula is: , in, The number of hours the gate is open per day is expressed in units of hours. Considering that ships need to alternate between upstream and downstream travel, the actual one-way travel time is... .

[0014] Furthermore, this application proposes that the safe distance between vessels be determined according to vessel type, with convoy distances based on one vessel length and single motorized vessels based on two vessel lengths; and that vessel speed be determined according to the lock classification. Level 1 ship lock , Level 1 ship lock , Level 1 ship lock .

[0015] As can be seen from the above, the present application provides a method for predicting the cargo throughput capacity of a lock during lock opening. This method includes classifying locks according to the applicable scenarios for lock opening and determining the interannual reference time; dividing the calculation period and calculating the average lock opening time during the period; calculating the Gini coefficient based on the Lorenz curve and the trapezoidal method to determine the annual uniformity; calculating the effective lock opening time by combining the interannual reference time and the annual uniformity; determining the ship navigation parameters and calculating the one-way single lock passage time and the average daily one-way lock passage frequency; and calculating the one-way annual cargo throughput capacity of the lock during lock opening by combining the ship load parameters and the cargo volume coefficient. By introducing the Gini coefficient to quantify the annual uniformity of lock opening time distribution and fixing the value range, this method effectively overcomes the problems of ignoring the unevenness of annual distribution and the instability of the coefficient of variation index in the prior art. It has the advantages of being able to reasonably quantify the uniformity of time distribution, having clear physical meaning, stable calculation results, and being compatible with multiple lock scenarios. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the Lorentz curve and the Gini coefficient; Figure 2 This is a schematic diagram of the application instance hub layout; Figure 3 This is a distribution chart of the monthly opening times of a certain ship lock in the experimental example; Figure 4 This is a Lorentz curve diagram of a lock in the experimental example; Figure 5 This is a comparison chart of the computational stability of the present invention and the prior art under different data years.

[0017] Figure 6 This is a graph showing the interannual variation of the annual variation coefficient of water flow in a certain lock in the experimental example. Detailed Implementation

[0018] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. The components of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0019] Traditional methods for calculating the throughput capacity of ship locks only consider the annual average time, completely ignoring the uneven distribution within the year, leading to significant discrepancies between the calculated results and actual values. Existing technologies introduce a water diversion unevenness coefficient based on the coefficient of variation for correction; however, this method uses the coefficient of variation as the core indicator for uniformity measurement, which suffers from technical limitations such as the lack of fixed upper and lower bounds in the value range, insufficient intuitive physical meaning, and high sensitivity to data sequence length and extreme values. Furthermore, it is only applicable to water diversion-type ship lock scenarios, limiting its applicability. Therefore, there is an urgent need to propose a method for calculating the throughput capacity of ship locks with clear physical meaning, stable and reliable results, and coverage of multiple ship lock scenarios.

[0020] To address this issue, this application proposes a method for predicting the cargo throughput capacity of a ship lock during lock opening. This method categorizes ship locks based on their applicable opening scenarios and determines an annual baseline time. It then divides the calculation period according to the cycle of lock opening time variation and calculates the average lock opening time for each period. Based on the Lorenz curve and trapezoidal method, it calculates the Gini coefficient of lock opening time distribution and determines the annual uniformity. Furthermore, it calculates the effective lock opening time based on the annual baseline time and annual uniformity. Next, it determines ship navigation parameters based on lock grade and ship type and calculates the one-way single-pass time and the average daily one-way pass frequency. Finally, it combines ship load parameters and cargo capacity coefficients to calculate the annual one-way cargo throughput capacity during lock opening.

[0021] This application provides a method for predicting the cargo throughput capacity of a ship lock when it is open, and its specific implementation may include the following steps: In step S1, the locks are first classified according to their applicable scenarios for lock opening, and a corresponding annual reference time is determined for each type of lock. Lock opening refers to the operation mode where the lock gates are directly opened to allow ships to pass through the lock chamber at a constant speed when the upstream and downstream water level difference meets a safety threshold. This mode can shorten the lock passage time and improve navigation efficiency. The annual reference time refers to the average or standard value of the lock's available opening time over a multi-year timescale, determined statistically or based on design conditions. This time serves as the basic time quantity for calculating the lock's throughput capacity.

[0022] In step S2, the year is divided into multiple calculation periods based on the changing cycle of the lock opening time. Subsequently, the average lock opening time within each calculation period is calculated under the interannual baseline conditions, and these average lock opening times are arranged in ascending order.

[0023] In step S3, the Gini coefficient of the lock opening time distribution is calculated based on the Lorenz curve and the trapezoidal method, and the annual uniformity is determined based on the Gini coefficient.

[0024] The Lorenz curve is a curve used to describe the fairness of allocation. In this application, it is used to visualize the cumulative distribution of gate opening times over different time periods. The trapezoidal method is a numerical integration method, which is used in this application to calculate the area between the Lorenz curve and the perfectly uniform distribution line, thereby quantifying the non-uniformity of gate opening time allocation.

[0025] The Gini coefficient is an indicator of the degree of uneven distribution, calculated based on the Lorenz curve, and its value range is typically from 0 to 1. In this application, the Gini coefficient is used to quantify the uneven distribution of lock opening time over a year; a higher value indicates a greater degree of unevenness.

[0026] In step S4, the effective lock opening time is calculated based on the established interannual reference time and intra-annual uniformity. Intra-annual uniformity is an index calculated based on the Gini coefficient, used to directly reflect the evenness of the distribution of lock opening time within a year. Its value range is fixed at [0,1], with a larger value indicating a more even distribution of lock opening time within the year.

[0027] Effective lock opening time refers to the total actual time available for ship passage, obtained by adjusting the interannual reference time after taking into account the uneven distribution of lock opening time throughout the year. This time can reasonably reflect the actual operational capacity of the lock.

[0028] In step S5, the navigation parameters of the vessel passing through the lock are determined based on the lock's class and representative vessel type, and the one-way single-pass time for the representative vessel type and the average daily one-way pass frequency of the lock are calculated. For example, vessel navigation parameters may include vessel length, width, draft, and speed within the lock chamber. The one-way single-pass time can be estimated based on the vessel's distance traveled within the lock chamber and its speed. The average daily one-way pass frequency can be calculated by a simple division between the available daily lock operating hours and the one-way single-pass time.

[0029] In step S6, the annual one-way cargo throughput capacity of the lock is calculated by combining the ship loading coefficient and the cargo volume imbalance coefficient. For example, the load factor can refer to the average deadweight tonnage of the ship, and the cargo volume coefficient can reflect the impact of the actual loading rate or cargo type on the cargo volume. The annual one-way cargo throughput capacity can be obtained by comprehensively calculating the average daily number of one-way passages, the effective lock opening time, the average deadweight tonnage, and the cargo volume coefficient.

[0030] This application quantifies the annual distribution uniformity of lock opening times by introducing a Gini coefficient calculated based on the Lorenz curve and trapezoidal method, and uses this to correct the interannual reference time, thus obtaining a more reasonable and effective lock opening time. This method overcomes the shortcomings of traditional coefficients of variation in terms of physical meaning, value range stability, and data sensitivity, improving the rationality and stability of the prediction results. Furthermore, by classifying lock scenarios and combining ship navigation and load parameters, this method can cover multiple lock types, solving the problems of large deviations between calculated results and actual conditions and limited applicability in existing technologies, and providing a basis for the reasonable assessment of lock cargo throughput capacity.

[0031] In some of the above-mentioned schemes in this application, it is proposed to classify ship locks according to the applicable scenarios for opening the locks and determine the annual reference time. However, in actual application, different types of ship locks have significant differences in hydrological characteristics and operating logic. If the ship locks are not subdivided and the reference time is not determined in a targeted manner, the selection of the annual reference time will lack specificity, which will affect the rationality of the subsequent calculation of the effective opening time.

[0032] In this regard, this application further proposes that in step S1, the locks are divided into estuary tidal zone locks and water resource allocation locks according to the lock opening scenario; the average value of the lock opening time measured over many years is used as the interannual reference time for estuary tidal zone locks, while the interannual reference time for water resource allocation locks is determined according to the scheduling or design hydrological conditions.

[0033] Specifically, the lock opening scenario refers to the operational mode of a lock where, under specific hydrological, geographical, and scheduling conditions, vessels can pass directly through the lock chamber without requiring lock raising or lowering operations. The availability of this mode is influenced by various factors, such as tides, river runoff, and reservoir scheduling. Classifying locks into estuary tidal zone locks and water resource allocation locks aims to categorize them based on their dominant influencing factors and operational mechanisms, facilitating the subsequent determination of interannual benchmark times. Estuary tidal zone locks are typically located at river estuaries or in areas significantly affected by tides, and their opening time is primarily influenced by the tidal cycle and tidal range. Water resource allocation locks, on the other hand, are mostly located in reservoirs, hydropower stations, or large-scale water conservancy projects, and their opening time is mainly affected by water resource management strategies such as upstream reservoir scheduling, downstream water demand, and runoff changes. In addition to the two classification methods mentioned above, locks can also be classified according to their geographical location (such as mountain locks and plain locks) or main function (such as flood control locks and irrigation locks). However, this application focuses on the impact of lock opening scenarios on the determination of interannual reference time.

[0034] The interannual reference time measures the total theoretically available operating time of a ship lock throughout the year and serves as the basis for predicting cargo throughput capacity. For ship locks in estuarine tidal zones, the opening time exhibits significant periodicity and randomness, influenced by natural factors such as tides and waves. Using the average of measured opening times over many years effectively smooths out short-term fluctuations and eliminates the impact of random factors, thus obtaining a statistically representative and stable interannual reference time. For example, the average annual total opening time can be calculated by collecting actual opening operation data over several consecutive years, such as collecting daily opening time data from the past 5, 10, or even longer periods and then calculating its annual average. Alternatively, a representative interannual reference time can be predicted and determined by establishing statistical models based on historical data, such as time series analysis models, which can capture long-term trends and periodic changes in tides.

[0035] For water resource allocation-type ship locks, their opening time is not entirely determined by natural hydrological conditions, but is significantly influenced by human intervention factors such as reservoir scheduling rules, water resource allocation plans, and hydrological conditions in engineering design. Therefore, determining the interannual benchmark time requires considering these specific scheduling or design constraints to reflect the actual operational situation. For example, an operational scheduling model of the reservoir or water conservancy project can be established to simulate the lock opening conditions under different hydrological years (e.g., high-water years, normal-water years, low-water years) and different scheduling objectives (e.g., power generation, water supply, flood control), and the average annual opening time can be statistically analyzed as the interannual benchmark. Alternatively, based on the typical hydrological conditions adopted in the lock engineering design (e.g., design flood level, design low-water level, design flow rate), combined with the lock's operating water level requirements and design navigation standards, the average annual opening time under these design conditions can be calculated. Furthermore, the interannual benchmark time for water resource allocation-type ship locks can be comprehensively evaluated and determined through expert experience methods, combining long-term operational data and the experience judgment of scheduling personnel.

[0036] Through the above technical solutions, this application provides a more reasonable and targeted method for determining the interannual reference time for locks with different operating mechanisms. Dividing locks into estuary tidal locks and water resource allocation locks effectively distinguishes their dominant influencing factors. For estuary tidal locks, using the average of measured lock opening times over many years effectively mitigates the randomness caused by tidal fluctuations, making the determined interannual reference time more representative and stable, avoiding deviations caused by short-term hydrological anomalies. For water resource allocation locks, determining the interannual reference time based on scheduling or design hydrological conditions fully considers human scheduling logic and engineering design constraints, ensuring that the reference time conforms to actual operating patterns and avoiding overestimation or underestimation that may result from simple averaging. This classification and targeted determination of the reference time provides more reasonable input parameters for subsequent calculations of the lock's effective opening time, significantly improving the rationality and stability of the prediction of lock opening cargo throughput capacity, and solving the problem of insufficient applicability of general calculation methods in different scenarios.

[0037] In some of the embodiments described above in this application, it is proposed to divide the lock into estuary tidal locks and water resource allocation locks to determine the interannual reference time. However, in the actual application of water resource allocation locks, due to the significant differences in the hydrological regulation mechanisms of different types of locks, if only a unified reference time determination method is used, it is difficult to accurately reflect the actual available time of the locks under different operating modes, which limits the rationality of the throughput capacity calculation results.

[0038] In response, this application further proposes to subdivide water resource allocation locks into water resource scheduling locks and runoff regulation locks. Specifically, for water resource scheduling locks, the interannual reference time is obtained by subtracting the average number of days of water regulation per year from the annual number of days of water passage; while for runoff regulation locks, the average number of days of lock opening per year under the design hydrological conditions is used as the interannual reference time.

[0039] This segmented approach aims to precisely match the physical operating characteristics and hydrological regulation mechanisms of different locks. Water resource scheduling locks refer to locks whose operation is significantly affected by water resource scheduling plans. For example, large-scale water diversion activities to meet agricultural irrigation, urban water supply, or ecological water replenishment may cause the locks to be unable to open during specific periods. The annual number of days the lock can be used for navigation typically refers to the total number of days theoretically available for navigation without water diversion interference. This can be determined based on the lock's design operating cycle or historical statistical data. The average annual number of days with water diversion refers to the average number of days each year when the lock cannot be opened or its operation is restricted due to water resource scheduling. This data can be obtained by analyzing historical scheduling records, hydrological monitoring data, or scheduling plans. For example, it can be estimated by counting the number of days each year when water levels exceed the lock's safe operating range due to water diversion, or by using the annual water diversion plan issued by the scheduling department. Another approach is to establish a hydrological-scheduling coupling model to simulate the number of days the lock can be used under different scheduling scenarios and then take its annual average.

[0040] Runoff-regulating locks are primarily influenced by natural runoff and the runoff regulation of upstream reservoirs or dams. Their opening time depends more on the natural hydrological processes of the river and the comprehensive scheduling of the reservoir for flood control and power generation. Design hydrological conditions refer to the typical hydrological scenarios upon which the lock was planned and designed, such as multi-year average hydrological conditions or hydrological conditions during specific high-water or low-water years. The average number of days the lock can be opened annually is determined through hydraulic calculations or operational simulations under these design hydrological conditions. For example, long-term hydrological data (such as 30 or 50 years) can be used for simulations to calculate the number of days the lock can be opened while meeting operational requirements such as the upstream and downstream water level difference and minimum navigable depth, and then the average value is taken. Another method is to calculate the average number of days the lock can be opened annually through numerical simulations or empirical formulas based on the lock's operating procedures and the water level-discharge relationship under design hydrological conditions.

[0041] Through the above technical solution, this application can effectively solve the problem of inaccurate determination of interannual reference time for water resource allocation type locks due to differences in hydrological regulation mechanisms. By further subdividing water resource allocation type locks into water resource scheduling type and runoff regulation type, and adopting different interannual reference time calculation methods accordingly, the actual available time of the locks under different operating modes can be more reasonably reflected. For water resource scheduling type locks, deducting the average number of days of water diversion per year can effectively eliminate the interference of non-navigable time caused by water diversion tasks, thereby more reasonably defining the actual reference time that can be used to open the lock. For runoff regulation type locks, determining the reference time based on the average number of days of lock opening per year under design hydrological conditions can fully consider the objective constraints of runoff fluctuations on lock operation, ensuring that the reference time setting conforms to the long-term operating rules of this type of lock. This classification approach allows the acquisition of benchmark time to no longer rely on a single statistical indicator, but to be specifically modified according to the specific functional attributes of the lock. This effectively solves the problem of differences in water resource utilization methods among different types of locks, and lays a reliable benchmark data foundation for the subsequent reasonable calculation of throughput capacity. As a result, it significantly improves the rationality and stability of the calculation results of cargo throughput capacity when the lock is opened.

[0042] In some of the above-mentioned schemes in this application, the calculation period is divided according to the variation cycle of the lock opening time, in order to statistically analyze the average opening time of each period and calculate the Gini coefficient. However, in practical applications, different types of locks are affected by hydrological, tidal or scheduling patterns, and their periodic characteristics of opening time fluctuations are significantly different. If there is a lack of targeted period division standards, the selection of the calculation period will not match the actual operation pattern, thus affecting the rationality and stability of the annual uniformity calculation results.

[0043] In this regard, this application further proposes that in S2, the opening time of the tidal lock is changed by half a month tide, and the opening time of the water resource allocation lock is changed by month or ten days.

[0044] The opening time of tidal locks in estuary tidal zones varies according to the semi-lunar tide. This technical feature aims to provide a periodic classification standard that conforms to the natural laws of estuarine tidal zone lock opening time statistics. The opening time of estuarine tidal zone locks is significantly affected by tidal fluctuations, and the semi-lunar tide cycle (usually the cycle of alternating spring and neap tides, approximately 14 to 15 days) can accurately capture the influence of tides on navigation time. Specifically, this can be achieved in two ways: one is to analyze and determine the precise dates of spring and neap tides based on long-term accumulated tidal observation data, thereby dividing the semi-lunar tide cycle; the other is to combine tidal level forecast information issued by local hydrological departments to predict and set the lock opening time period within the semi-lunar tide cycle.

[0045] The estuary tidal zone ship lock uses the arithmetic mean of the measured time series of lock openings over many years as the interannual reference time. The specific calculation formula is as follows: , In the formula, For the data period; For the first Total annual gate opening time, in days.

[0046] The opening time of water resource allocation-type ship locks varies on a monthly or ten-day period. This technical feature aims to provide a periodic classification standard for the statistics of the opening time of water resource allocation-type ship locks, which conforms to their scheduling or runoff patterns. The opening time of such ship locks is mainly affected by manual scheduling plans or seasonal runoff changes. The monthly (approximately 30 days) or ten-day (approximately 10 days) cycle can effectively cover the execution rhythm of water resource scheduling plans or seasonal fluctuations in runoff.

[0047] Specifically, the interannual reference time for water resource scheduling locks is obtained by subtracting the average number of days for water diversion from the annual number of days of water passage; the specific calculation formula is as follows: , in, The number of days of spaceflight completed per year; The average number of days for water diversion per year, in days, is determined based on the planned water diversion volume for the design level year. For runoff-regulating ship locks, the average number of days the locks are open under design hydrological conditions is used as the interannual reference time. The specific calculation formula is as follows: , in, The number of days the gate is open annually based on the design hydrological conditions, expressed in days.

[0048] Through the above technical solutions, this application provides a more reasonable method for dividing the opening time variation period for different types of locks. For estuarine tidal locks, setting the opening time variation period to semi-monthly tides directly corresponds to the alternation of spring and neap tides, ensuring that the statistically calculated average opening time for each period is more consistent with actual operating conditions and avoiding misjudgments of navigation time due to tidal fluctuations. For water resource allocation locks, setting the opening time variation period to monthly or ten-day periods effectively captures the regular changes in water resource scheduling plans or seasonal runoff, avoiding the interference of random fluctuations caused by too short a period or the smoothing of time distribution characteristics caused by too long a period. This method of classifying and setting the period makes the data sequence used in the subsequent calculation of the Gini coefficient based on the Lorenz curve more physically meaningful and representative, thereby significantly improving the ability of the annual evenness index to characterize the actual operating status of the lock, laying a solid data foundation for the subsequent reasonable calculation of effective opening time, and thus improving the rationality and stability of the calculation results of the lock's cargo throughput capacity.

[0049] In some of the above-mentioned schemes in this application, the Gini coefficient is proposed to quantify the uniformity of lock opening time distribution within the year. However, in the actual calculation process, there is a lack of specific mathematical calculation models and standardized processing procedures for how to transform discrete lock opening time data sequences into uniformity indices with clear physical meaning and numerical stability. This makes it difficult to accurately evaluate the lock opening time distribution characteristics of different types of locks at different time scales.

[0050] In this regard, this application further proposes that, in S3, the Gini coefficient is calculated using the trapezoidal method, with the following formula: , , , in, Gini coefficient; To calculate the total number of time periods; This refers to the total time the gate is open. For the front The cumulative value of the gate opening time for each period; The index for the cumulative count over the time period. ,when hour, ; For traversing indices within a single time period; For the first The gate opening time within a specific time period; Specifically, the Gini coefficient is calculated using the trapezoidal method, which approximates the calculation by discretizing the area under the Lorenz curve into the sum of the areas of a series of trapezoids. The Lorenz curve is a graph reflecting the uneven distribution of resources; its horizontal axis typically represents the cumulative percentage of the population, and its vertical axis represents the cumulative percentage of wealth. In this application, the horizontal axis corresponds to the cumulative percentage of the calculation period, and the vertical axis corresponds to the cumulative percentage of the opening time. The opening time for each period is calculated... Sort in ascending order and calculate their cumulative values. The Lorenz curve can be constructed using this method. The trapezoidal method, by summing the areas of the trapezoids formed by these discrete points, can accurately calculate the area between the Lorenz curve and the perfectly uniform distribution line, thus obtaining the Gini coefficient. This calculation method can effectively smooth data fluctuations, making the calculation results more robust to the length of the data sequence and extreme values. For example, when processing semi-monthly tidal cycle data of tidal locks or monthly / ten-day cycle data of water resource allocation locks, the trapezoidal method can stably reflect the distribution characteristics of their lock opening times.

[0051] Based on this, the annual uniformity The calculation formula is This formula will use the Gini coefficient. (Reflecting the degree of unevenness) is converted into annual uniformity. (Reflects uniformity). Gini coefficient The value of is typically between 0 and 1, where 0 represents perfect uniformity and 1 represents perfect non-uniformity. Therefore, subtracting 1 from 1... Annual uniformity The value range of Gini coefficient is also fixed between [0,1], where 0 represents complete non-uniformity and 1 represents complete uniformity. This conversion gives the uniformity index an intuitive physical meaning; the larger the value, the more evenly the lock opening time is distributed throughout the year. For example, when the lock opening time is very evenly distributed across different periods within a year, the Gini coefficient... When the Gini coefficient approaches 0, the annual uniformity (Uintra) approaches 1; conversely, when the opening times are highly concentrated in a few periods, the Gini coefficient... If it approaches 1, then the annual uniformity is... Approaching 0.

[0052] Specifically, the Gini coefficient is an internationally recognized indicator for measuring the degree of equality in income distribution and resource allocation; its geometric meaning can be precisely described by the Lorenz curve. Let there be a total of... Each time period The average opening time of the gate over many years is ( , Representing the year, For the first Year, No. (the opening time of each period), Sort in ascending order Calculate the cumulative value Based on the cumulative percentage over the time period. The horizontal axis represents the cumulative proportion of gate opening time. Plot the Lorentz curve on the ordinate (e.g.) Figure 1 (As shown). Gini coefficient Defined as the area A between the Lorentz curve and the 45° absolute uniform line and the area of ​​the triangle below the absolute uniform line. The ratio, that is The value range is [0,1]. =0 indicates that it is completely uniform. This indicates absolute non-uniformity.

[0053] The Gini coefficient can be approximated using the trapezoidal method, and the following derivation can be obtained:

[0054] In the formula, The total gate opening time is denoted by . This formula accurately reflects the degree of uneven distribution by using the area difference between discrete points and the absolutely uniform line.

[0055] Gini coefficient The derivation process is as follows: First, let's assume... The sample data (as mentioned in the text, are arranged in ascending order of time length) (a number of gate opening time segments), sorted from smallest to largest: .

[0056] Definition: Cumulative sum , indicating the preceding The sum of the values ​​of the smallest samples; the sum , representing the total value of all samples.

[0057] Secondly, construct the Lorentz curve coordinate system. The horizontal axis of the Lorentz curve ( The vertical axis represents the proportion of the cumulative sample size. () represents the cumulative percentage.

[0058] For the One point, x-axis: ; Vertical axis: ;starting point: ;end: .

[0059] Next, use the trapezoidal method to find the area under the Lorentz curve. Area under the Lorentz curve can be The approximation is obtained by summing consecutive trapezoidal shapes. Adjacent points... and This forms a trapezoid with a base width (horizontal axis step size) of: .

[0060] The area of ​​the trapezoid is (upper base + lower base) × height ÷ 2: . Accumulate all trapezoidal surfaces ( ): .

[0061] Expand and sum: .

[0062] Substitution , .

[0063] therefore, .

[0064] Finally, the relationship between the Gini coefficient and area is determined. In the geometric definition of the Gini coefficient: the line of absolute fairness ( The area of ​​the triangle formed by the line and the horizontal axis is ; Gini coefficient Defined as "the area between the line of absolute fairness and the Lorenz curve" divided by "the area of ​​the triangle below the line of absolute fairness". That is: .

[0065] The above results Substitute and get .

[0066] This yields the formula: .

[0067] Through the above technical solution, this application provides a standardized and numerically stable method to quantify the annual uniformity of lock opening times. Introducing the trapezoidal method to calculate the Gini coefficient effectively handles discrete lock opening time data sequences, avoiding the sensitivity of traditional methods to data sequence length and extreme values, thereby improving the reliability of the calculation results. Simultaneously, the Gini coefficient is transformed into annual uniformity. The value range is fixed in [0,1], giving the index a clear physical meaning and intuitive interpretability, facilitating horizontal comparison and evaluation between different types of locks. This precise and stable uniformity quantification method provides a solid foundation for the subsequent calculation of effective lock opening time, thereby improving the rationality and applicability of the lock cargo throughput capacity calculation results. It effectively solves the technical defects of existing uniformity quantification indices, such as the lack of fixed upper and lower bounds, insufficient intuitive physical meaning, and sensitivity to data sequences.

[0068] In some of the schemes described above in this application, the annual uniformity of lock opening time is calculated using the Gini coefficient. However, in the actual process of predicting cargo throughput capacity, obtaining only the uniformity index is not enough to directly quantify the impact on the actual available time of the lock. This results in the inability to effectively convert the unevenness of time distribution throughout the year into an effective time parameter that can be used to calculate throughput capacity, thereby affecting the rationality of the throughput capacity calculation results.

[0069] In this regard, this application further proposes the following formula for calculating the effective opening time of the lock in S4: , in, For the effective gate opening time; As the interannual base time; The annual uniformity.

[0070] Specifically, the effective gate opening time This refers to the total actual time available for ship passage, taking into account the evenness of lock opening times throughout the year. It is not a simple interannual average time, but rather a more accurate reflection of actual usable navigation time after evenness correction. Its purpose is to serve as a reasonable time benchmark for subsequent cargo throughput capacity calculations, avoiding overestimation or underestimation of actual throughput capacity due to uneven time distribution within the year. This time quantity can be calculated by using the interannual benchmark time... With annual average The effective time can be obtained by multiplying the values, or by taking a weighted average of the opening times of different time periods, where the weighting factors reflect the utilization efficiency or importance of each time period.

[0071] Interannual base time This refers to the average lock opening time over a multi-year timescale, without considering the uneven distribution of time within the year. It is typically a baseline time determined based on historical data or design conditions, serving as the basis for calculating effective lock opening time and representing the lock's basic available time during long-term operation. This time can be the average of measured lock opening times over many years, or determined based on scheduling or design hydrological conditions, such as the annual number of days of water flow regulation minus the average number of days of water diversion for water resource scheduling locks, or the average number of days of lock opening under the design hydrological conditions for runoff regulation locks.

[0072] Annual uniformity This is an indicator that measures the evenness of lock opening times throughout the year. Its value range is fixed at [0,1], with larger values ​​indicating a more even distribution of lock opening times within the year. Its purpose is to correct interannual reference times. The uneven distribution of time within the year is quantified as a reduction factor for actual available time.

[0073] Through the above technical solution, this application introduces an effective gate opening time. This core parameter establishes the interannual reference time. With annual average The mathematical mapping relationship between these relationships allows for a reasonable correction of the actual available time of the locks. Specifically, this scheme utilizes interannual reference time. As a base time quantity, it is multiplied by the annual evenness. This approach transforms the previously abstract uniformity index into a concrete effective time length. The unique aspect of this method is that it not only considers the lock's basic navigation time on an annual scale but also reduces the unevenness of time distribution within the year through a uniformity factor. When uniformity is low, it means that the lock opening time is extremely unevenly distributed throughout the year, and in this case, the effective lock opening time... This will be reduced accordingly, thus avoiding the problem of overestimating throughput capacity caused by directly using multi-year averages. Through this calculation method, the uneven distribution of time within the year caused by factors such as hydrological fluctuations and scheduling plans can be directly quantified as time loss, providing a reliable time benchmark for subsequent reasonable calculation of cargo throughput capacity. This ensures that the prediction results can more realistically reflect the actual throughput potential of the lock under complex operating conditions, significantly improving the rationality and stability of the calculation method.

[0074] In some of the schemes mentioned above in this application, although the macroscopic navigation potential of the lock is calculated by the effective lock opening time, in actual engineering applications, the lack of detailed modeling of individual ship navigation behavior makes it impossible to accurately quantify the time consumption during a single lock passage, which in turn affects the rationality of the calculation results of cargo throughput capacity.

[0075] In response, this application further proposes, in S5, determining the safe distance and speed of vessels based on the lock level and representative vessel type, and calculating the one-way single-pass time; the one-way single-pass time... The calculation formula is: , in, The safe passage length of a ship through the lock, in units of Including the length of the ship's physical body Safety distance ,Right now ; The speed of a ship, in units of .

[0076] Specifically, lock class refers to the design navigation capacity of a lock, typically classified based on the maximum dimensions (e.g., length, width, draft) and deadweight tonnage of navigable vessels. Different lock classes have different navigation requirements and safety standards. Representative vessel type refers to the type of vessel that is representative or dominant in a specific waterway or lock; its size, load capacity, speed, and other parameters reflect the typical navigation characteristics of that section of waterway. Vessel safety distance. This refers to the minimum distance that vessels should maintain between themselves or between a vessel and the lock structure to ensure navigational safety and avoid collisions or grounding during lock passage. The determination of this distance typically considers factors such as vessel maneuverability, current conditions, lock structure dimensions, and vessel speed. For example, it can be set based on empirical formulas, simulations, or actual observation data; or, according to the regulations of shipping management authorities, different safety distances can be set for different vessel types and different waterway conditions. (Vessel speed) This refers to the actual speed of a vessel during its passage through a lock. The determination of this speed is influenced by various factors, including the lock class, current conditions, the vessel's own power performance, crew operating habits, and safety regulations. For example, recommended speeds can be set for different lock classes based on lock design specifications or shipping management regulations; or the average speed of different vessel types under a specific lock can be obtained through statistical analysis of historical lock passage data. The calculation of one-way, single-pass lock passage time is also included. Aimed at quantifying the time required for a single vessel or fleet to complete a one-way passage through the lock, it is a key indicator for evaluating the microscopic passage efficiency of a lock. This is achieved by measuring the safe passage length of vessels through the lock. Divide by ship speed Then multiply by a unit conversion factor (e.g., 60 to convert seconds to minutes) to obtain the one-way single-pass time in minutes. This calculation method simplifies the complex gate-crossing process into a uniform linear motion model, facilitating engineering applications. One-way, single-pass gate-crossing time. Calculation formula A standardized and quantifiable method is provided to calculate the time required for a single lock passage, ensuring the reasonableness and comparability of the calculation results. This formula directly expresses the safe lock passage length for a vessel. (unit ) and ship speed (unit By combining these, we can obtain the time in seconds through division, and then divide by 60 to convert the unit to obtain the gate passage time in minutes. The definition of safe passage length for vessels through locks clarifies its composition, ensuring that the actual space occupied by the vessel and necessary safety margins are fully considered when calculating passage time. (Vessel body length) Safety clearance can be obtained through ship registration information, design drawings, or actual measurements. The value is determined based on factors such as the lock's grade, ship type, and hydrological conditions. Simply adding the two together yields the result. . For ship speed, the physical quantity and unit of ship speed used in the calculation are clearly defined, ensuring the physical consistency of the formula calculation. Ship speed The determination of the lock level can be based on historical data statistics, regulations of the lock management department, or empirical values ​​based on the lock level and representative ship type.

[0077] Through the above technical solution, this application introduces the safe lock passage length for ships. With ship speed These two key parameters, determined based on the lock's class and representative ship type, enable refined and quantitative calculations of the time consumed in a single lock passage. Specifically, this is achieved by calculating the ship's physical length... Safety distance The length of safe passage for a ship through the lock is obtained by adding them together. The design fully considers the actual physical space occupied by ships within the lock chamber and the necessary safety margin. Based on this, the safe passage length of ships through the lock is utilized. With ship speed The ratio, combined with unit conversion, is used to reasonably calculate the one-way single-pass time. This technical solution effectively compensates for the shortcomings of existing methods in modeling individual ship navigation behavior, avoiding prediction errors in cargo throughput capacity due to the lack of quantification of micro-time consumption. By reasonably quantifying the single lock passage time, it lays the foundation for subsequent calculations of the lock's annual one-way cargo throughput capacity by combining the effective lock opening time. It provides more robust and detailed data support, thereby significantly improving the rationality and stability of the prediction results for the cargo throughput capacity of the lock.

[0078] In some of the solutions mentioned above in this application, the lock throughput capacity is evaluated by calculating the one-way single-pass time. However, in actual operation, since ships need to pass through alternately in the upstream and downstream directions, if only the single-pass time is considered, it cannot accurately reflect the effective time allocation available for one-way passage within the limited daily lock opening hours. This results in the calculation of the average number of one-way passes per day lacking constraints on the logic of alternating two-way passage, which in turn affects the rationality of the calculation results of cargo throughput capacity.

[0079] In response, this application further proposes, in S5, to calculate the average daily number of one-way passages based on the daily gate operation time; the average daily number of one-way passages... The average number of one-way passages per day depends on the daily operating hours of the gate and the one-way passage time. The calculation formula is: , in, The number of hours the gate is open per day is expressed in units of hours. Considering that ships need to alternate between upstream and downstream travel, the actual one-way travel time is... .

[0080] The daily lock operation time refers to the total time that a lock can actually be used for operation within a day. This time is usually constrained by various factors, such as lock operation regulations, scheduling plans, hydrological conditions (such as tides and water levels), and nighttime navigation restrictions. For example, in some locks, the daily lock operation time may be fixed at 16 hours per day, while in others it may be dynamically adjusted according to real-time hydrological forecasts or scheduling instructions to maximize navigation efficiency or meet the needs of water resource allocation.

[0081] Average number of one-way passages per day This is a key indicator for measuring the one-way passage efficiency of a ship lock within a specific time period. Its function is to convert the available time resources of the lock into specific ship passage frequencies, providing a quantitative basis for subsequent cargo throughput capacity prediction. The calculation of this frequency depends on the daily operating hours of the lock and the one-way passage time of a single ship. .

[0082] The alternating passage of vessels in upstream and downstream directions is an inherent physical constraint of lock operation. For most single-line locks, at any given time, the lock can only serve vessels traveling in one direction; either upstream or downstream vessels can pass through simultaneously. This constraint is essential for ensuring the safe and efficient operation of the lock.

[0083] Given the constraint that vessels must alternate between upstream and downstream passage, the actual one-way passage time is: This means that if the daily operating hours of the lock are... In theory, the available passage time for both upstream and downstream vessels is [missing information]. Half of the time is allocated. This time allocation method ensures fairness in two-way traffic and reflects the lock's strategy for allocating limited time resources in actual operation.

[0084] Through the above technical solution, this application fully considers the actual constraints of alternating upstream and downstream passage of ships during lock operation when calculating the average daily number of one-way lock passages. This is achieved by adjusting the daily lock operation hours. The actual one-way travel time is obtained by halving the original value. This avoids overestimating the actual throughput capacity of the lock by simply adding up the two-way passage time. This approach reduces the average daily number of one-way passages. The calculations more closely reflect actual operating conditions, ensuring a reasonable allocation of effective time available for one-way passage within the limited daily gate operation hours. This is combined with previously calculated one-way single-pass passage times. The average number of one-way passages per day is calculated using the following formula: ,in, This refers to the daily operating hours of the gate. This system will specify the one-way available time. By directly dividing by the single gate passage time, a direct conversion of time resources to passage frequency (times / day) is achieved. This is different from the calculation method that does not consider bidirectional alternating passage (directly using...). Compared to the previous method, this method incorporates the alternating passage constraints of up and down traffic by converting the calculation to half, thus avoiding an overestimation of the number of one-way passages and providing a passage frequency parameter that conforms to actual operational constraints for subsequent calculations of annual freight throughput capacity.

[0085] In some of the solutions mentioned above in this application, the lock passage time and number of passages are determined by calculating ship navigation parameters. However, in actual engineering applications, there is often a lack of unified quantitative standards for the values ​​of ship safety distance and navigation speed. This leads to subjectivity and uncertainty in parameter selection when calculating the passage capacity of different ship types and locks of different grades, which in turn affects the rationality and universality of the prediction results.

[0086] In response, this application further proposes that the safe distance between vessels be determined according to vessel type, with convoy distances based on one vessel length and single motorized vessels based on two vessel lengths; and that vessel speed be determined according to the lock classification. Level 1 ship lock , Level 1 ship lock , Level 1 ship lock .

[0087] Specifically, the safe clearance between vessels refers to the minimum distance that vessels must maintain between themselves or between a vessel and the lock structure to ensure navigational safety and avoid collisions during lock passage. Its value directly affects the safe passage length of a vessel through the lock. The calculation affects the one-way single-pass time. One approach is to dynamically adjust the safety distance based on the ship type (e.g., bulk carrier, container ship, tanker, etc.) and its position in the fleet (leader, follower). For example, for large container ship fleets, additional safety margins can be added at the bow and stern to cope with situations involving high inertia and relatively poor maneuverability. Another approach is to determine the recommended safety distance for different ship types under different hydrological conditions through statistical analysis, combining actual lock operation experience and historical accident data. For example, in situations with turbulent currents or low visibility, the safety distance can be appropriately increased. In this application, specifically, for a fleet, the safety distance is set at 1 times the ship's length; for a single motorized vessel, the safety distance is set at 2 times the ship's length. This setting considers the complexity of overall fleet maneuvering and the difference in flexibility of individual vessels, providing clear parameters for subsequent calculations.

[0088] Meanwhile, ship speed This refers to the speed at which a vessel can safely navigate within a lock chamber or pilotway. This parameter is used to calculate the one-way, single-pass lock passage time. The key input is the lock speed, and its rationality directly affects the assessment of lock passage efficiency. One approach is to determine the recommended speed for different lock classes through actual measurements or simulations, based on the actual operating conditions and design specifications of the lock. For example, factors such as the width of the lock chamber, water depth, length of the approach channel, and ship type can be considered to conduct multi-condition simulations. Another approach is to establish an optimization model for ship speed by combining the ship's dynamic performance, maneuverability, and the lock's navigation environment (such as water flow speed and wind force) to maximize navigation efficiency while ensuring safety. In this application, specifically, ship speed is directly correlated with the lock class, for example, Level 1 ship lock , Level 1 ship lock , Level 1 ship lock This setting reflects the differences in design standards, navigation conditions, and management requirements among different levels of locks, and provides standardized speed parameters for predicting the throughput capacity of locks of different levels.

[0089] The above technical solution standardizes and quantifies the setting of safe distances and speeds for vessels, effectively solving the problems of lack of unified standards and subjectivity and uncertainty in the selection of vessel navigation parameters when calculating the cargo throughput capacity of locks. Specifically, it directly links the safe distances to the vessel type (fleet or single motorized vessel) and sets them to 1 times and 2 times the vessel length, respectively, thus ensuring the safe passage length for vessels through the lock. The calculations are more objective and accurate, avoiding errors caused by experience-based judgments. At the same time, the ship's speed... The parameters are correlated with the lock levels (Level III, Level IV, and Level V) and specific values ​​are provided. This ensures that the selection of ship navigation parameters has a clear basis in different lock environments, thereby improving the one-way single-pass lock passage time. and average daily number of one-way turns The calculation rationality is improved. This standardized parameter setting not only enhances the rationality of the prediction results of the cargo throughput capacity of the lock opening, but also strengthens the universality and reliability of the prediction method, making it more applicable to different ship types and locks of different grades, and providing more solid data support for the planning, design and operation management of locks.

[0090] In some of the above-mentioned schemes in this application, the annual one-way cargo throughput capacity of the lock is calculated by the average daily number of one-way passages, the effective lock opening time, the ship load parameters, and the cargo volume coefficient. However, in actual engineering applications, due to the fluctuation of ship loading status and the unevenness of cargo volume demand in the shipping market, it is difficult to accurately reflect the actual carrying capacity of the lock in a complex logistics environment if only a single theoretical calculation value is used, resulting in a deviation between the predicted results and the actual cargo volume.

[0091] In this regard, this application further proposes, in S6, the annual freight throughput capacity of the gate in one direction. The calculation formula is: , in, This represents the average number of one-way turns at the gate per day. This refers to the average load capacity per lock passage (in tons). This refers to the ship's loading coefficient. This is the coefficient for imbalance in transport volume.

[0092] Among them, ship loading coefficient The vessel loading coefficient can be determined based on local freight survey statistics. Ship loading coefficient used to reflect "effective utilization rate of a single ship" This refers to the ratio of the actual cargo load on a ship under specific operating conditions to its rated deadweight tonnage. This coefficient is not a fixed constant but a dynamic reduction factor, representing the proportion of the ship's nominal carrying capacity realized in actual operation. (Ship Loading Coefficient) Due to the influence of cargo stowage factor, cargo hold capacity limitations, and route water depth, this value is usually ≤1.0. Ship Loading Coefficient It typically does not rely on theoretical calculations, but rather on sampling and regression analysis of actual cargo arrival data of ships of the same tonnage class based on recent cargo statistics for the target shipping area (generally long-term data from several decades).

[0093] Transportation imbalance coefficient It is used to reflect the degree of peak concentration. Its calculation formula is as follows: .

[0094] Transportation imbalance coefficient This refers to the ratio of the highest monthly freight volume within a statistical period (usually a full calendar year) to the average monthly freight volume for that year. This coefficient is used to characterize the intensity of uneven fluctuations in cargo arrivals over time. (Freight volume imbalance coefficient) It is always greater than or equal to 1.0. The larger the coefficient, the higher the concentration of freight volume throughout the year (e.g., affected by seasonal production, weather windows, or maintenance cycles of upstream and downstream enterprises).

[0095] During the feasibility study phase, peak months are identified by retrieving local historical monthly throughput or transport volume data (generally long-term data spanning several decades), and the peak month is calculated by dividing the peak month's value by the average of the annual total divided by 12. If complete statistics are unavailable, estimates can also be made based on the seasonal characteristics of the hinterland's economy and industries.

[0096] Through the aforementioned technical solution, this application, when calculating the annual one-way freight throughput capacity of a lock during lock operation, not only considers the lock's effective passage time and the ship's theoretical load capacity, but also further introduces a ship loading coefficient α and a freight volume imbalance coefficient β. The introduction of the ship loading coefficient α effectively corrects the deviation between theoretical full load and actual non-full load, allowing the calculation results to more realistically reflect the ship's cargo loading status in actual operation, avoiding the problem of overestimating throughput capacity due to assumed full load. The introduction of the freight volume imbalance coefficient β fully considers the fluctuations in shipping market demand throughout the year, such as seasonal or cyclical changes, thus enabling the predicted annual freight throughput capacity to better adapt to changes in actual market demand, avoiding overestimation of throughput capacity during demand troughs or underestimation during demand peaks. Therefore, this solution can more reasonably calculate the actual carrying capacity of a lock in a complex logistics environment, significantly improving the rationality and stability of the calculation results, and providing more solid data support for lock operation management and waterway planning.

[0097] Experimental Example like Figures 2-4 As shown, a certain ship lock is part of the Jianghuai connection section of a certain project. The lock is a water resource management lock, which can be opened for operation outside of water management periods. The representative design vessel type is... Class 1 cargo ship (68m × 13.8m × 3.2m (length × width × draft)), annual number of passages through the locks The design level has an average of [number] days of water diversion per year. Navigation time on the opening day of the gate .

[0098] S1. Determine the interannual reference time. This lock is a water resource scheduling type, and the interannual reference time is the number of days of water diversion minus the number of days of annual water passage: 。

[0099] S2. Based on the water diversion scheduling cycle, the calculation period is divided into 12 time periods per month; the average gate opening time for each month is calculated and arranged in ascending order.

[0100] S3. Calculate the Gini coefficient and intra-annual uniformity. The Gini coefficient is calculated based on the trapezoidal method. Therefore, the annual uniformity is: .

[0101] S4. Calculate the effective gate opening time. .

[0102] S5. Calculate the average daily number of lock passages. For a 2000t class vessel, the safe clearance distance is taken as twice the vessel length. Safe lock passage length. , Ship speed at the lock One-way, single-pass time:

[0103] Working hours per day when the gate is open Considering alternating traffic flow in both directions, the average daily number of gate passages in one direction is:

[0104] S6. Calculate annual throughput capacity. Take the average tonnage per pass through the lock. Loading coefficient Unevenness coefficient Substituting into the formula, we get... .

[0105] To further verify the rationality of the method of the present invention in uniformity quantification, the Gini coefficient method of the present invention and the coefficient of variation method described in the prior art (Chinese invention patent ZL202311578512.1) were used to conduct a multi-dimensional comparative analysis on the same gate opening time series.

[0106] First, a comparison of the reasonableness of the value range. This invention uses the Gini coefficient to construct the intra-annual uniformity, with a fixed value range of [0,1], where 0 represents complete non-uniformity and 1 represents complete uniformity, with clear physical meaning. Existing technologies use the mean of the coefficient of variation to quantify non-uniformity, such as... Figure 6As shown, the calculated annual variation coefficient of the lock's water diversion volume ranges from 0.23 to 3.07. When the mean variation coefficient is less than 1, the water diversion time is unreasonably reduced, which actually increases the effective lock opening time. When the mean variation coefficient exceeds 1.93, the calculated effective lock opening time drops to zero, which clearly contradicts engineering reality. The above results indicate that the variation coefficient can only reflect the degree of data dispersion and cannot reasonably characterize the uniformity of time distribution. The Gini coefficient method of this invention has a reasonable value range and clear physical meaning, and can better fit the actual physical characteristics of the annual distribution of lock opening time.

[0107] Second, a comparison of the sensitivity of data over time. For example... Figure 5 As shown, six sets of data sequences of different lengths—5 years, 10 years, 20 years, 30 years, 40 years, and 55 years—were selected for comparison. Under the same data period, the existing coefficient of variation method is highly sensitive to data length: the shorter the data period, the more pronounced the discrete characteristics, and the greater the fluctuation in the calculated results, with a maximum deviation of 56% compared to the 55-year long sequence. In contrast, the method of this invention has a deviation of only 1.0% from the 55-year long sequence under the 5-year short sequence, and the stability of the results is significantly better than the comparative method.

[0108] As can be seen from the comparison, different methods for quantifying intra-annual non-uniformity have a significant impact on the throughput calculation results. The method of this invention is superior to the existing technology in terms of both the rationality of the value range and the stability of the results.

[0109] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for predicting the cargo throughput capacity of a ship lock when it is open, characterized in that, The method includes: S1. Classify ship locks according to the applicable scenarios for their opening and determine the corresponding annual benchmark time; S2. Divide the calculation period according to the change cycle of the lock opening time, and calculate the average opening time of each period under the annual benchmark condition of the lock and arrange them in ascending order; S3. Calculate the Gini coefficient of the lock opening time distribution based on the Lorenz curve and trapezoidal method, and determine the annual uniformity based on the Gini coefficient; S4. Calculate the effective opening time of the lock based on the interannual reference time and the annual uniformity of the lock. S5. Determine the navigation parameters of ships passing through the lock based on the lock level and representative ship type, and calculate the one-way single-pass time of the representative ship type and the average daily one-way pass number of the lock. S6. Calculate the annual one-way freight throughput capacity of the lock when it is open, taking into account the ship loading coefficient and the freight volume imbalance coefficient. In S6, the annual freight throughput capacity of the gate in one direction is opened. The calculation formula is: ， in, This represents the average number of one-way passages per day at the lock. This refers to the average load capacity per lock passage (in tons). This refers to the ship's loading coefficient. This is the coefficient for imbalance in transport volume.

2. The method for predicting cargo throughput capacity of a ship lock upon opening, as described in claim 1, is characterized in that... In S1, the locks are divided into estuary tidal zone locks and water resource allocation locks according to the lock opening scenario. For estuary tidal locks, the average of the measured lock opening times over many years is used as the annual reference time. For water resource allocation locks, the annual reference time is determined based on the scheduling or design hydrological conditions.

3. The method for predicting cargo throughput capacity of a ship lock upon opening, as described in claim 2, is characterized in that... Water resource allocation type locks are divided into water resource scheduling type locks and runoff regulation type locks. The water resource scheduling type locks obtain the interannual reference time by subtracting the average number of days of water regulation from the annual number of days of water passage, while the runoff regulation type locks use the average number of days of lock opening under the design hydrological conditions as the interannual reference time.

4. The method for predicting cargo throughput capacity of a ship lock upon opening, as described in claim 3, is characterized in that... In S2, the opening time of the tidal lock varies with the semi-monthly tide, while the opening time of the water resource allocation lock varies with the month or ten-day period.

5. The method for predicting cargo throughput capacity of a ship lock upon opening, as described in claim 4, is characterized in that... In S3, the Gini coefficient is calculated using the trapezoidal method, and the formula is: ， ， ， in, Gini coefficient; To calculate the total number of time periods; This refers to the total time the gate is open. For the front The cumulative value of the gate opening time for each period; The index for the cumulative count over the time period. ,when hour, ; For traversing indices within a single time period; For the first The gate opening time within a specific time period; The formula for calculating the annual uniformity is: ； in, The value represents the uniformity within the year, and its range is fixed at [0,1]. The larger the value, the more evenly the opening time of the gate is distributed within the year.

6. The method for predicting cargo throughput capacity of a ship lock according to claim 5, characterized in that, In S4, the formula for calculating the effective opening time of the lock is as follows: ， in, For the effective gate opening time; As the interannual base time; The annual uniformity.

7. The method for predicting cargo throughput capacity of a ship lock upon opening, as described in claim 6, is characterized in that... In S5, the safe distance and speed of ships are determined based on the lock level and representative ship type, and the one-way single-pass time is calculated; the one-way single-pass time... The calculation formula is: ， in, The safe passage length of a ship through the lock, in units of Including the length of the ship's physical body Safety distance ,Right now ; The speed of a ship, in units of .

8. The method for predicting cargo throughput capacity of a ship lock upon opening, as described in claim 7, is characterized in that... In S5, the average daily number of one-way passages is calculated based on the daily gate operation time; the average daily number of one-way passages... The average number of one-way passages per day depends on the daily operating hours of the gate and the one-way passage time. The calculation formula is: ， in, The number of hours the gate is open per day is expressed in units of hours. Considering that ships need to alternate between upstream and downstream travel, the actual one-way travel time is... .

9. The method for predicting cargo throughput capacity of a ship lock upon opening, as described in claim 8, is characterized in that... Safe distances between vessels are determined by vessel type: one length for convoys and twice the length for single motorized vessels; vessel speeds are determined by lock classification. Level 1 ship lock , Level 1 ship lock , Level 1 ship lock .

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