A method for loading and distributing cargo in inland waterway shipping

Abstract

The present invention belongs to the technical field of inland waterway shipping management, and in particular to a method for loading and stowing cargo in inland waterway shipping. The method comprises the following steps: classifying the objects to be transported according to their mass and volume characteristics, determining the best loading scheme based on the full load rate and rate of return of inland bulk carriers as the optimal loading optimization model, and completing the loading by determining the cargo stowage scheme of each bay position through the loading plan of each port. The present invention fully considers the characteristics of inland waterway shipping, and considers the fact that inland waterway shipping is highly managed by ship owners, and proposes a scheme based on the highest loading rate and profit rate of ships, combined with the characteristics of the efficiency of assembly at each port to further optimize the assembly and stowage. The scheme can realize the best loading and stowage scheme for ships on their planned routes in a shorter time, and while better meeting the expectations of ship owners, it can also guarantee the loading rate of ships to the greatest extent and improve the efficiency of cargo transportation within the route.

Description

Technical Field

[0001] The invention belongs to the technical field of inland waterway shipping management, and in particular relates to a method for loading and distributing goods for inland waterway shipping. Background Art

[0002] With the advancement of domestic shipbuilding technology and the continuous optimization of waterway conditions, my country's inland waterway shipping has developed rapidly and has become one of the important factors in promoting the development of the river basin economy. On the other hand, the loading and stowage of inland waterway cargo is different from that of traditional sea transportation. The conditions of different inland waterways vary greatly, there are many ports with uneven technical levels, and there are many types of cargo. There is a lack of relatively unified standards and industrial management and control processes, so the transportation and stowage plan is difficult. Summary of the invention

[0003] The object of the present invention is to provide an inland waterway cargo loading and stowing method mainly used for inland waterway cargo loading and stowing planning according to actual needs.

[0004] To achieve the above purpose, the present invention adopts the following technical solution.

[0005] A method for loading and stowing inland waterway cargo of the present invention mainly comprises the following steps:

[0006] Step 1: Collect original shipping and freight data

[0007] The cargo to be transported is divided into m categories according to their mass and volume characteristics, and the distance L between the departure and destination ports of each category of cargo is collected. m , Cargo capacity V m , corresponding port transportation cost P m ;

[0008] Step 2: Determine the optimal loading plan

[0009] The optimization objective function is established with the full load factor and rate of return of inland bulk carriers as the optimization targets:

[0010] The objective function of the highest full load rate

[0011] The objective function of maximizing the rate of return;

[0012] Where I represents the total number of segmented flights, α i represents the capacity factor of the i-th leg, k i,m represents the total amount of the mth type of cargo in the i-th voyage, T i represents the sailing time of the i-th voyage (including the loading and unloading time at the i-th port), I represents the total number of segmented voyages; p i,m represents the revenue of the i-th voyage of the m-th category of cargo, βi represents the cost control coefficient of the i-th voyage;

[0013] where α i and β i It is used to control the full load and revenue standards at a specific time during the corresponding voyage. If the voyage passage cost increases due to weather, the cost control coefficient needs to be reduced. If the ship's transportation volume is limited during the voyage, the capacity coefficient α should be reduced. i ;

[0014] Determine the restrictions based on the ship's carrying capacity, i.e. the ship's capacity limit;

[0015] Get the optimal loading scheme model

[0016] Determine the best loading plan based on the aforementioned optimization model to obtain the total amount of various types of cargo required to be loaded at each port;

[0017] Step 3: Build the inverted box model

[0018] The i-th voyage corresponds to its initial port as the i-th port, and the loading target is expressed as the objective function:

[0019]

[0020] Among them, c i,j,r is the beige pointer,

[0021] Where R represents the total number of ship bays, and r represents the bay number;

[0022] The constraints of the objective function include:

[0023] Limitation of the number of seats: Indicates that each bay in each port can only be used once; where i = 1, 2...I, j = 2, 3...I;

[0024] Load Limitation: Indicates that the quantity of ships unloading at each port is not less than the quantity required to be loaded c i,j , to ensure that the capacity is sufficient;

[0025] Capacity Limitation: Indicates that the empty space after uninstallation is written ir Not less than the space required for the cargo to be loaded i,j ;

[0026] Quality limit: w ir ≤w r,max , represents the total mass w of the cargo in r bays after unloading ir Not exceeding the mass limit w r,max;

[0027] The above objective function and constraints constitute the container-reversing model for cargo stowage;

[0028] Step 4: Cargo loading

[0029] Loading optimization is performed based on the following steps:

[0030] D1. Based on the total amount of cargo loaded and unloaded at each port, the corresponding bays are divided according to the ship bays. In addition to the above general principles, for cargoes that exceed the capacity of a bay, they should be allocated to non-adjacent bays;

[0031] According to the type M, quantity and quality of the port cargo determined in step 2, the cargo is arranged in the reverse direction of the voyage arrival order and the cargo quality, that is, from the final arrival port to the initial port, from heavy to light, to obtain the cargo sequence {h i,j}={h 1,1 ,h 1,2 ...h 1,m}+{h 2,1 ,h 2,2 ...h 2,M}...{h I,1 ,h I,2 ...h 1,M};

[0032] h i,j Indicates a certain type of goods ranked in the jth position from heavy to lightest at the i-th port; if a certain type of goods does not exist in the corresponding port, the corresponding sequence is deleted;

[0033] D2. At the initial port, according to the cargo sequence {h i,j}, and the order of the ports in each port is used to allocate bays. At each port, the bays are allocated according to the cargo sequence {h i,j} Load from the middle position of the bay outwards in sequence;

[0034] D3. Arrive at the next port i to unload the corresponding cargo, and record the unloading volume d at each bay during the unloading process r , obtain the cargo information to be loaded, according to the cargo sequence {h i,j {Determine whether there is an empty bay at the corresponding location. If so, determine the optimal location for loading according to the model in step three, and update the bay status at the same time. If not, search for the optimal feasible bay for the goods according to the box inversion model. The search order is to search adjacent bays first, assemble the goods according to the search results, and update the bay information at the same time.

[0035] Further improvement or specific implementation of the above-mentioned inland waterway cargo loading and stowage method,

[0036] The distance L mIndicates the flight distance; capacity V m It refers to the volume ratio of the mth category of cargo. For cargo with lower average density, it refers to the ratio of its volume to the ship capacity. For cargo with higher average density, it refers to the ratio of its mass volume to the ship load. The transportation cost P m It refers to the transportation cost per unit distance of the mth type of goods; M refers to the total number of goods.

[0037] For further improvement or specific implementation of the above-mentioned inland waterway shipping cargo loading and stowage method, if the container is damaged or lost during the loading process or there is a temporary loading task, the bay position information should be searched and updated again after the cargo information is updated to optimize the next port loading task.

[0038] The further improvement or specific implementation method of the above-mentioned inland waterway cargo loading and stowage method also includes D4, obtaining the corresponding cargo to be unloaded and loaded at the current port i, selecting a certain proportion of bays in the order from the periphery to the middle and from the top to the bottom, counting the number of cargoes belonging to subsequent ports in the bays, selecting several ports in the order from most to least and according to the principle of proximity, and taking out all the cargoes of the corresponding ports in the bays; counting the cargo information taken out and to be loaded at subsequent ports, and rearranging the cargoes from the final port to the initial port from heavy to light to obtain a cargo sequence {H i,j}, collect free bay information.

[0039] Its beneficial effects are:

[0040] The present invention takes full account of the characteristics of inland waterway transportation and the high degree of management of inland waterway transportation by ship owners, and proposes a scheme based on the maximum loading rate and profit margin of ships, combined with the characteristics of assembly efficiency of each port to further optimize the assembly and loading scheme. This scheme can achieve the best loading and loading scheme for ships on their planned routes in a shorter time, while better meeting the expectations of ship owners, maximizing the ship loading rate and improving the efficiency of cargo transportation within the route. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a basic process step diagram for inland waterway shipping cargo loading and stowage methods. DETAILED DESCRIPTION

[0042] The present invention is mainly used for inland waterway shipping loading and stowage planning to improve the corresponding planning efficiency. The specific scheme of the present invention is described below in conjunction with specific examples.

[0043] The loading process of ocean shipping vessels should follow a series of basic principles, including giving priority to loading cargo farthest from the destination to reduce the number of container unloading, giving priority to loading large-mass cargo to lower the center of gravity of the ship and improve stability, and giving priority to loading small-volume cargo to enhance structural stability and prevent cargo damage.

[0044] As for inland waterway shipping, due to the limited shipping capacity and the small size of bulk carriers themselves, ship owners pay more attention to the full load rate and yield rate during the transportation process, and optimize the loading and stowage plan on this basis.

[0045] To this end, the main steps of the inland waterway cargo loading and stowage method of the present invention are as follows: Figure 1 As shown, it mainly includes the following steps:

[0046] Step 1: Collect original shipping and freight data

[0047] Most inland ports have stable service areas, mainly various planned industrial zones or ports dedicated to specific industries. Therefore, the cargo types, loading sizes and destinations of each port are relatively stable, and the route status is basically the same. In the actual loading process, loading is generally carried out according to the loadable capacity of each cargo at each port. Under normal circumstances, the full load rate and rate of return of inland bulk carriers are mainly related to the location of the cargo loading and unloading port, the unit cargo capacity and the corresponding port route operation cost. For this reason, firstly, the cargo to be transported is divided into m categories according to its quality and volume characteristics, and the distance L between the departure and destination ports of each cargo is collected. m , Cargo capacity V m , corresponding port transportation cost P m ;

[0048] Table 1 Shipping freight original data collection table

[0049] Serial number distance capacity Shipping costs 1 <![CDATA[L 1 ]]> <![CDATA[V 1 ]]> <![CDATA[P 1 ]]> 2 <![CDATA[L 2 ]]> <![CDATA[V 2 ]]> <![CDATA[P 2 <!-- 3 -->]]> ... ... ... ... m <![CDATA[L m ]]> <![CDATA[V m ]]> <![CDATA[P m ]]> ... ... ... ... M <![CDATA[L M ]]> <![CDATA[V M ]]> <![CDATA[P M ]]>

[0050] The distance L m Indicates the flight distance; capacity V m It refers to the volume ratio of the mth category of cargo. For cargo with lower average density, it refers to the ratio of its volume to the ship capacity. For cargo with higher average density, it refers to the ratio of its mass volume to the ship load. The transportation cost P m It refers to the transportation cost per unit distance of the mth type of goods; M refers to the total number of goods;

[0051] Step 2: Determine the optimal loading plan

[0052] The optimization objective function is established with the full load factor and rate of return of inland bulk carriers as the optimization targets, namely:

[0053] The objective function of the highest full load rate

[0054] The objective function of maximizing the rate of return

[0055] Where I represents the total number of segmented flights, α irepresents the capacity factor of the i-th leg, k i,m represents the total amount of the mth type of cargo in the i-th voyage, T i represents the voyage time of the i-th voyage, I represents the total number of segmented voyages; p i,m represents the revenue of the i-th voyage of the m-th category of cargo, β i represents the cost control coefficient of the i-th voyage;

[0056] where α i and β i It is used to control the full load and revenue standards at a specific time during the corresponding voyage. If the voyage passage cost increases due to weather, the cost control coefficient needs to be reduced. If the ship's transportation volume is limited during the voyage, the capacity coefficient α should be reduced. i ;

[0057] Determine the restrictions based on the ship's carrying capacity, i.e. the ship's capacity limit;

[0058] Get the optimal loading scheme model

[0059] Through a reasonable loading plan, the utilization rate of the ship's loading space can be improved. Based on the objective function, the optimal loading plan can be determined by combining other necessary factors to obtain the total amount of various types of cargo required for loading and unloading at each port. Based on this, the loading optimization can be carried out to determine the loading order.

[0060] Step 3: Build the inverted box model

[0061] The cargo assembly process is limited by the loading capacity and cargo voyage. There is inevitably a problem of mutual obstruction between cargoes. It is necessary to transfer the cargo that hinders the current port cargo unloading, that is, the container transfer. The ultimate goal of loading is to reduce the amount of container transfer. r , the initial port of the i-th voyage is the i-th port, so the loading target can be expressed as the objective function:

[0062]

[0063] Among them, c i,j,r is the beige pointer,

[0064] Where R represents the total number of ship bays, and r represents the bay number;

[0065] The constraints of the objective function include:

[0066] Limitation of the number of seats: Indicates that each bay in each port can only be used once; where i = 1, 2...I, j = 2, 3...I;

[0067] Load Limitation: Indicates that the quantity of ships unloading at each port is not less than the quantity required to be loaded c i,j , to ensure that the capacity is sufficient;

[0068] Capacity Limitation: Indicates that the empty space after uninstallation is written ir Not less than the space required for the cargo to be loaded i,j ;

[0069] Quality limit: w ir ≤w r,max , represents the total mass w of the cargo in r bays after unloading ir Not exceeding the total mass limit w at that position r,max ;

[0070] The above objective function and constraints constitute the container-reversing model for cargo stowage;

[0071] Step 4: Cargo Loading Optimization

[0072] Based on the above foundation, after the loading scheme with the best loading rate and rate of return is determined, the repeated loading of goods can be reduced through a reasonable loading sequence. The present invention further optimizes the loading based on the following steps.

[0073] D1. Based on the total amount of cargo loaded and unloaded at each port, the corresponding bays are divided according to the ship bays. In addition to the above general principles, for cargoes that exceed the capacity of a bay, they should be allocated to non-adjacent bays;

[0074] According to the type, quantity and quality of the port cargo determined in step 2, the cargo is arranged in the reverse direction of the voyage arrival order and the cargo quality, that is, from the final arrival port to the initial port, from the heaviest to the lightest, to obtain the cargo sequence {h i,j}={h 1,1 ,h 1,2 ...h 1,<}+{h 2,1 ,h 2,2 ...h 2,M}...{h I,1 ,h I,2 ...h 1,M};

[0075] h i,j Indicates a certain type of cargo ranked in the jth position from heavy to lightest at the i-th port; if a certain type of cargo does not exist at the corresponding port, the corresponding sequence is deleted;

[0076] D2. At the initial port, according to the cargo sequence {h i,j}, the order of the ports in the port is used to allocate bays, and the bays in each port are allocated according to the cargo sequence {h i,j} Load from the middle position of the bay outwards in sequence;

[0077] D3. Arrive at the next port i to unload the corresponding cargo, and record the unloading volume d at each bay during the unloading process r , according to the goods sequence {h i,j} Obtain the information of the goods to be loaded, determine whether there is a vacant space in the corresponding bay, if so, determine the optimal position for loading according to the model in step 3, and update the bay state at the same time; if not, go to step D4;

[0078] D4. Obtain the corresponding cargo to be unloaded and loaded at the current port i, select a certain proportion of bays in the order from the periphery to the middle and from the top to the bottom, count the quantity of cargo belonging to the subsequent ports in the bays, select several ports in the order from most to least and according to the principle of proximity, and take out all the cargo of the corresponding ports in the bays;

[0079] Count the cargo information that has been taken out and to be loaded at the subsequent ports, and rearrange the cargo from the final port to the initial port from the heaviest to the lightest to obtain the cargo sequence {H i,j}, collect the available bay information, according to the goods sequence {H i,j}, the order of the ports in the port is used to allocate bays, and the bays in each port are allocated according to the cargo sequence {H i,j}Load in sequence from the center position of the bay outwards.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for loading and stowing cargo for inland waterway shipping, characterized in that: The steps include: Step 1: Collect original shipping and freight data The cargo to be transported is divided into m categories according to their mass and volume characteristics, and the distance L between the departure and destination ports of each category of cargo is collected. m , Cargo capacity V m , transportation cost P m ; Step 2: Determine the optimal loading plan The optimization objective function is established with the full load factor and rate of return of inland bulk carriers as the optimization targets: The objective function of the highest full load rate The objective function of maximizing the rate of return; Where I represents the total number of segmented flights, α i represents the capacity factor of the i-th leg, k i,m represents the total amount of the mth type of cargo in the i-th voyage, T i represents the sailing time of the i-th voyage; p i,m represents the revenue of the i-th voyage of the m-th category of cargo, β i represents the cost control coefficient of the i-th voyage; M refers to the total types of cargo; where α i and β i Used to control the full load and revenue standards at specific times within the corresponding voyage; Determine the restrictions based on the ship's carrying capacity, i.e. the ship's capacity limit; Get the optimal loading scheme model Determine the best loading plan based on the aforementioned optimization model to obtain the total amount of various types of cargo required to be loaded at each port; Step 3: Build the inverted box model The i-th voyage corresponds to its initial port as the i-th port, and the loading target is expressed as the objective function: Among them, c i,j,r is the beige pointer, Where R represents the total number of ship bays, and r represents the bay number; The objective function constraints include: Limitation of the number of seats: Indicates that each bay in each port can only be used once; where i = 1, 2...I, j = 2, 3...I; Load Limitation: Indicates that the quantity of ships unloading at each port is not less than the quantity required to be loaded c i,j , to ensure that the capacity is sufficient; Capacity Limitation: Indicates the empty space after unloading f ir Not less than the space required for the cargo to be loaded i,j ; Quality limit: w ir ≤w r,max , represents the total mass w of the cargo in r bays after unloading ir Not exceeding the total mass limit w at that position r,max ; The above objective function and constraints constitute the container-reversing model for cargo stowage; Step 4: Cargo Loading Optimization Loading optimization is performed based on the following steps: D1. Based on the total amount of cargo loaded and unloaded at each port, the corresponding bays are divided according to the ship bays. In addition to the above constraints, for cargoes that exceed the capacity of a bay, they should be allocated to non-adjacent bays; According to the type M, quantity and quality of the port cargo determined in step 2, the cargo is arranged in the reverse direction of the voyage arrival order and the cargo quality, that is, from the final arrival port to the initial port, from heavy to light, to obtain the cargo sequence {h i,j }={h 1,1 ,h 1, 2...h 1,M }+{h 2,1 ,h 2,2 ...h 2,M }...{h I,1 ,h I,2 ...h 1,M }; h i,j Indicates a certain type of goods ranked in the jth position from heavy to lightest at the i-th port; if a certain type of goods does not exist in the corresponding port, the corresponding sequence is deleted; D2. At the initial port, according to the cargo sequence {h i,j }, and the order of the ports in each port is used to allocate bays. At each port, the bays are allocated according to the cargo sequence {h i,j } Load from the middle position of the bay outwards in sequence; D3. Arrive at the next port i to unload the corresponding cargo, and record the unloading volume d at each bay during the unloading process r , obtain the cargo information to be loaded, according to the cargo sequence {h i,j }Determine whether there is a vacant bay at the corresponding location. If so, determine the optimal position for loading according to the model in step 3, and update the bay status at the same time. If not, search for the optimal feasible bay for the goods according to the box inversion model. The search order is to search adjacent bays first, assemble the goods according to the search results, and update the bay information at the same time.

2. The method for loading and stowing inland waterway cargo according to claim 1, characterized in that: The distance L m Indicates the flight distance; capacity V m refers to the volume share of the mth category of goods; the transportation cost P m It refers to the transportation cost per unit distance of the mth type of goods; M refers to the total number of goods.

3. The method for loading and stowing inland waterway cargo according to claim 1, characterized in that: If the container is damaged or lost during the loading process or there is a temporary loading task, the bay information should be searched and updated again after the cargo information is updated to optimize the loading task at the next port.

4. The method for loading and stowing inland waterway cargo according to claim 1, characterized in that: It also includes D4, obtaining the corresponding cargo to be unloaded and loaded at the current port i, selecting a certain proportion of bays in the order from the periphery to the middle and from the top to the bottom, counting the quantity of cargo belonging to subsequent ports in the bays, selecting several ports in the order from most to least and according to the principle of proximity, and taking out all the cargo of the corresponding ports in the bays; counting the cargo information taken out and to be loaded at subsequent ports, and rearranging the cargo from the final port to the initial port from heavy to light to obtain the cargo sequence {H i,j }, collect free bay information.

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