A method for optimizing the configuration of logistics functional areas in subway passenger and freight sharing stations

Abstract

The present invention belongs to the field of underground logistics transportation, and provides a method for optimizing the configuration of logistics functional areas of subway passenger and freight shared stations, including: formulating a logistics space construction strategy for non-transfer underground double-deck island stations; setting a shared station logistics space modeling strategy; establishing a shared station logistics space layout objective function and decision variables; establishing shared station logistics space layout constraints; constructing a shared station logistics space layout double-layer planning model; solving a shared station logistics space layout double-layer planning model. The present invention has novel ideas and strong applicability, improves the rationality of spatial allocation and construction economy of subway stations after adding logistics functions, and ensures that urban underground logistics distribution is carried out efficiently and stably based on the subway system.

Description

Technical Field

[0001] The present invention belongs to the field of underground logistics transportation, and specifically relates to a method for optimizing the configuration of logistics functional areas in a subway passenger and freight sharing station. Background Art

[0002] The subway freight system is a new mode of transportation that uses the subway to carry out coordinated transportation of passengers and freight underground in the city. Compared with independently constructed underground logistics systems, it is cheaper and easier to implement, and can effectively improve the efficiency of urban logistics distribution. The system makes full use of subway infrastructure and surplus transportation capacity to achieve unimpeded automated transportation, bringing significant social, economic and environmental benefits such as improving traffic congestion, saving land resources, reducing pollution emissions, and improving the resilience of urban supply chains. From the perspective of the construction needs of modern new cities and new districts, the subway freight system is an inevitable trend in urban logistics innovation and an important supplement to the future urban comprehensive transportation system.

[0003] Subway passenger and freight sharing stations are node facilities in the subway passenger and freight integrated transportation network. According to their location in the subway network, they can be divided into intermediate passenger and freight stations and passenger and freight transfer stations. Such stations can receive freight units sent from subway terminals or depots with trains, and provide necessary logistics operation sites and facilities for the goods arriving at the station. The processed goods can be sent out of the station to surrounding customer locations or stored in the station hall area waiting for passengers to pick them up.

[0004] The logistics space layout of subway passenger and freight sharing stations is to expand or transform the underground area of ​​subway stations according to certain functional relationships, equip the stations with necessary logistics operation facilities and equipment, enable the stations to play the functions of loading and unloading, handling, warehousing, and outbound delivery of goods, and improve the station's cargo circulation capacity by optimizing the layout and configuration of functional areas. Subway passenger and freight sharing stations have the characteristics of compact space, dense cargo flow, and high coordination requirements. It is necessary to formulate a layout plan based on the consideration of the expandable space boundaries, capacity settings, and facility selection to improve the economy of station construction and station service capabilities. Summary of the invention

[0005] The purpose of the present invention is to provide an underground double-deck subway passenger and freight sharing station (hereinafter referred to as "sharing station") that meets the requirements of automated cargo handling, establish a set of coordinated configuration optimization methods for logistics functional areas and logistics operation facilities within the station, and provide the optimal layout of the shared station cargo hall under realistic constraints such as spatial distance, transportation channels, and minimum service capacity requirements.

[0006] The technical solution to achieve the purpose of the present invention is: a method for optimizing the configuration of logistics functional areas in a subway passenger and freight sharing station, comprising the following steps:

[0007] Step (1): Formulate a logistics space construction strategy for a non-transfer underground double-deck island station, including a strategy for dividing passenger and freight operation spaces in the subway station and setting up logistics functional areas that need to be configured;

[0008] Step (2): Set up a shared station logistics space modeling strategy, including the setting of subway station logistics space grid units, the internal facility positioning selection strategy of the logistics functional area, and the calculation method of the material handling distance of the functional area;

[0009] Step (3): Establish the objective function and decision variables of the shared station logistics space layout, including the objective function of minimizing the station logistics space construction cost, the objective function of minimizing the station logistics operation facility installation and maintenance cost, the objective function of minimizing the cargo handling distance within the station, the objective function of maximizing the station cargo circulation capacity, and the objective function of maximizing the station logistics function aggregation degree;

[0010] Step (4): Establish shared station logistics space layout constraints, including functional area shape constraints, functional area layout constraints, functional area distance constraints, transportation channel and path constraints, station cargo capacity and circulation capacity constraints, and station logistics space construction budget constraints;

[0011] Step (5): Construct a two-level planning model for the shared station logistics space layout;

[0012] Step (6): Solve the two-level planning model for the shared station logistics space layout.

[0013] Furthermore, the strategy for dividing the passenger and freight operation space of the subway station in step (1) is as follows:

[0014] Relying on the station hall space station to complete the internal logistics operations, the station platform is equipped with a cargo platform for trains to stop and load and unload. After the cargo is unloaded on the platform, it is lifted to the logistics operation area on the station hall for centralized processing. Finally, the cargo is lifted to the ground cargo kiosk at the station exit by using the vertical shaft or sent out through the secondary underground pipeline.

[0015] The logistics functional areas in step (1) specifically include:

[0016] ① Loading and unloading operation area: that is, the station cargo platform, which provides a loading and unloading platform for subway freight trains; ② Platform-station hall vertical handling area: automatically lift the arriving goods to the station hall level through the lifting shaft, and at the same time lower the empty freight units to the platform level for recovery with the train; ③ Station hall-ground vertical handling area: lift the processed goods to the external ground space through the lifting shaft; ④ Incoming goods temporary storage area: provide classification, queuing, stacking and cross-handling places for station hall goods; ⑤ Unpacking and recycling area: disassemble the freight units transported by the subway, take out the goods and hand them over to the sorting facilities; ⑥ Warehousing operation area: provide storage space for goods or freight units that are not delivered immediately; ⑦ Sorting operation area: according to the delivery purpose of express parcels ⑧ Cargo sorting and loading area: marking, checking, packaging and loading of the sorted goods, classifying the goods according to the distribution form, quantity and transportation capacity, and determining the delivery priority and loading number; ⑨ Pipeline connection area: organizing the terminal underground logistics site, providing space for capsule cars to load and unload goods, dispatch and dock; ⑩ Logistics management area: operating and managing station logistics business; ⑪ Automatic guided vehicle AGV channel: arranging channels for AGV to travel between the functional areas of the subway station freight terminal; ⑫ Ground kiosk: storing goods lifted from the inside of the station, serving as a place for pedestrians to pick up and deliver goods.

[0017] Furthermore, the subway station logistics space grid unit setting in step (2) is specifically as follows:

[0018] The plane space of the station hall used for logistics operations is regarded as a grid of equal size and closely arranged, and the position of each functional area in the space is located by specifying the occupancy relationship of the plane grid;

[0019] The specific strategy for the internal facility positioning and selection of the logistics functional area in step (2) is as follows:

[0020] Considering the three mutually constrained variables of facility cost, occupied space and performance parameters, the operating facilities are selected; based on the zone architecture strategy with added zone directional decision, the internal facilities of the logistics functional area of ​​the subway station are arranged to meet the following rules: 1) The shape of any optional facility is rectangular; 2) The length and width of any optional facility are integer multiples of the grid side length; 3) The vertices of the arranged facilities must coincide with the vertices of the grid; 4) Gaps should be reserved between the facilities to realize internal cargo handling;

[0021] The specific calculation method for the material handling distance of the functional area in step (2) is:

[0022] The cargo handling process of the shared station is transformed into a type of obstacle-avoiding Mann shortest path problem, and the shortest obstacle-avoiding cargo handling path in the venue is obtained by solving the problem.

[0023] The transport path is calculated using the actual transport distance, requiring that the goods can only move vertically or horizontally on the arranged AGV channel and must avoid internal facilities in other functional areas.

[0024] Furthermore, the station logistics space construction cost objective function in step (3) minimizes the station construction cost, specifically:

[0025] Min (1)

[0026] Where, SP: freight terminal hall construction area, that is, the sum of the areas of each logistics functional area and AGV channel; c s : Construction cost of underground space per grid area of ​​the station; CO 建造 : Construction cost of freight terminal hall infrastructure; : grid unit side length; I: subway station logistics functional area set, indexed by i; M: freight station hall planable area grid number set along the X direction, indexed by m; N: freight station hall planable area grid number set along the Y direction, indexed by n; : 0-1 decision variable, when the grid with coordinates (m, n) is assigned to functional area i, the value is 1, otherwise it is 0; : 0-1 indicator variable, when the grid with coordinates (m, n) is used to arrange the AGV channel, the value is 1, otherwise it is 0;

[0027] The objective function of the station logistics operation facility installation and maintenance cost in step (3) minimizes the station logistics facility cost, specifically:

[0028] (2)

[0029] (3)

[0030] In the formula, CO 购置 :Procurement and installation costs of logistics-related facilities, depreciation to daily basis; CO 运维 : Daily operation and maintenance costs of facilities; J i : The set of optional operating facilities for functional area i, with j as index; : The purchase and installation cost of optional facility j in functional area i; : The number of installation facilities j in functional area i; : The service life of optional facility j in functional area i, calculated in days; : Operation and maintenance cost of optional facility j in functional area i, per day;

[0031] The objective function of the intra-station cargo handling distance in step (3) minimizes the intra-station cargo handling distance, specifically:

[0032] (4)

[0033] Where, CD (i, i'): the shortest obstacle avoidance distance between the center of functional area i and the center of functional area i'; : Binary indicator variable, if the cargo flow path from the center of functional area i1 to the center of functional area i2 passes through grid (m, n), the value is 1, otherwise it is 0; , : Binary indicator variable, if functional area i1, i2 is arranged in the freight terminal hall, the value is 1, otherwise it is 0.

[0034] The objective function of the station freight flow capacity in step (3) maximizes the station freight flow capacity, specifically:

[0035] (5)

[0036] In the formula, CV 流通 : The freight flow capacity of the subway station; CV B2-B1 、CV B1-地面 、CV 暂存 Respectively represent the cargo handling efficiency of the platform-station hall vertical handling area, the station hall-ground vertical handling area, and the incoming goods temporary storage area; CV 拆箱 、CV 分拣 、CV 理货 、CV 接驳 They represent the cargo handling efficiency of the unpacking and recycling area, the sorting operation area, the tallying and loading area, and the pipeline connection area, respectively. The expressions are as follows:

[0037] (6)

[0038] In the formula, : Conversion factor between freight units and bulk cargo in subway transportation; : The number of goods that can be processed in parallel by optional facility j in functional area i; : The processing efficiency of optional facility j in functional area i, hours; : Binary indicator variable, if the functional area i is the platform-station hall vertical transfer area, the value is 1, otherwise it is 0; : Binary indicator variable, if the functional area i is the station hall-ground vertical handling area, the value is 1, otherwise it is 0; : Binary indicator variable, if the functional area i is the pipeline connection area, the value is 1, otherwise it is 0; : Binary indicator variable, if functional area i is a temporary storage area for incoming goods, the value is 1, otherwise it is 0; : Binary indicator variable, if functional area i is a box unpacking recycling area, the value is 1, otherwise it is 0; : Binary indicator variable, if functional area i is the sorting operation area, the value is 1, otherwise it is 0; : Binary indicator variable, if functional area i is the tally loading area, the value is 1, otherwise it is 0;

[0039] The objective function of the station logistics function aggregation degree in step (3) maximizes the station logistics function aggregation degree, specifically:

[0040] (7)

[0041] Where, CR: aggregation degree of station logistics function; : Binary indicator variable, if functional area i is arranged in the freight terminal hall, the value is 1, otherwise it is 0; R i : The aggregation degree of functional area i and all its extremely strong / strong / relatively strong correlation level functional areas, the expression is as follows:

[0042] (8)

[0043] In the formula, : Binary indicator variable, if functional area i and functional area i' are extremely strongly associated, strongly associated or relatively strongly associated, the value is 1, otherwise it is 0.

[0044] Furthermore, the functional area shape constraints in step (4) specifically include:

[0045] 1) Specify the spatial shape of the freight terminal hall, grid unit division, and positioning functional areas to ensure that the plane grid occupied by the logistics space of each functional area is a complete and regular rectangle. The expression is as follows:

[0046] (9);

[0047] (10);

[0048] 2) The slenderness ratio of any logistics functional area is required not to exceed the set range. The expression is as follows:

[0049] (11);

[0050] In the formula, : The maximum allowable slenderness ratio of functional area i; , Respectively represent the number of grid cells occupied by functional area i in the X and Y directions;

[0051] 3) The shape of the freight terminal hall is required to be rectangular, that is, the number of plane grids distributed along any X row or Y column is equal, and the expression is as follows:

[0052] (12)

[0053] (13)

[0054] 4) The geometric center of any functional area must be located at the geometric center of a grid, that is, the edge of any functional area must be composed of an odd number of grid cells. The expression is as follows:

[0055] (14);

[0056] The functional area layout constraints in step (4) are as follows:

[0057] 1) Specify the number of functional areas, the layout range, and the internal facility layout requirements of the functional areas. Except for the logistics management area, each functional area is equipped with at least one set of corresponding operating facilities. The expression is as follows:

[0058] (15);

[0059] In the formula, : Binary indicator variable, if zone i is a logistics management zone, the value is 1, otherwise it is 0;

[0060] 2) A unique vertical handling area is arranged between the cargo platform B2 layer and the cargo terminal hall B1 layer, as well as between the cargo terminal hall and the ground. At the same time, the cargo terminal hall is equipped with a unique pipeline connection area and logistics management area. The number of other functional areas arranged is not less than 1, and the expression is as follows:

[0061] (16)

[0062] (17)

[0063] In the formula, : Binary indicator variable, if area i is a storage operation area, the value is 1, otherwise it is 0;

[0064] 3) The layout range of the platform-station hall vertical handling area, the station hall-ground vertical handling area, and the pipeline connection area is specified as follows:

[0065] (18)

[0066] (19)

[0067] In the formula, (m1, m2) and (n1, n2) represent the grid numbers corresponding to the areas that can be arranged in the platform-station hall vertical handling area in the X and Y directions respectively; (m3, m4) and (n3, n4) represent the grid numbers corresponding to the areas that can be arranged in the station hall-ground vertical handling area in the X and Y directions respectively; (m5, m6) and (n5, n6) represent the grid numbers corresponding to the areas that can be arranged in the pipeline connection area in the X and Y directions respectively;

[0068] 4) Ensure that relevant operation facilities can be configured only after the functional area has been constructed. The expression is as follows:

[0069] (20).

[0070] Furthermore, the functional area distance constraint in step (4) is specifically:

[0071] 1) Limit the distance between functional areas and facilities to ensure that the projection distance between the two most adjacent functional areas in the X and Y directions, including the AGV channel, does not exceed the construction length and width of the freight terminal hall, and the sum of the area of ​​each functional area and the area of ​​the AGV channel does not exceed the construction area of ​​the freight terminal hall. The expression is as follows:

[0072] (twenty one)

[0073] (twenty two)

[0074] (twenty three)

[0075] In the formula, : The projection distance and grid number between the center of functional area i1 and the center of functional area i2 along the Y direction; : The projection distance between the center of functional area i1 and the center of functional area i2 along the X direction, the number of grids; L: The maximum allowable construction length of the freight terminal hall in the X direction, the number of grids; W: The maximum allowable construction width of the freight terminal hall in the Y direction, the number of grids;

[0076] 2) Ensure that any functional area i1 does not overlap or interfere with any functional area i2. The expression is as follows:

[0077] (twenty four)

[0078] Where, g2: the minimum allowable distance between any two functional areas;

[0079] 3) Ensure that the functional area to be arranged must be one of the nine logistics functional areas of the freight terminal hall, as expressed as follows:

[0080] (25);

[0081] 4) Ensure that there is no interference between the internal facilities of any functional area. The facilities must maintain a set distance. The length, width and sum of all horizontal and vertical distances of the configured facilities shall not exceed the length and width of the functional area. The expression is as follows:

[0082] (26)

[0083] (27)

[0084] 5) Ensure indicator variables , and Consistent with the meaning of the decision variables, the expression is as follows:

[0085] (28)

[0086] Where: : Binary indicator variable, which is 1 if the nth row of grid horizontally passes through facility j installed in functional area i, otherwise it is 0; : Binary indicator variable, which is 1 if the mth row of grid vertically passes through facility j installed in functional area i, otherwise it is 0;

[0087] The specific transport channel and path constraints in step (4) are:

[0088] 1) Ensure that the AGV channel is adjacent to each functional area. The expression is as follows:

[0089] (29)

[0090] 2) Ensure that there is no overlap or interference between the logistics functional area and the AGV channel. The expression is as follows:

[0091] (30)

[0092] 3) It is stipulated that cargo handling can only be carried out when the grid is assigned to the AGV channel. The expression is as follows:

[0093] (31)

[0094] In the formula, : Binary indicator variable, if the cargo flow path from the center of functional area i1 to the center of functional area i2 passes through grid (m, n), the value is 1, otherwise it is 0;

[0095] 4) Ensure that the cargo flow paths between functional areas do not pass through the obstacle area, that is, the grid area occupied by facilities. The expression is as follows:

[0096] (32)

[0097] In the formula, : Binary indicator variable, the value is 1 if grid (m, n) is occupied by facility j in functional area i, otherwise it is 0.

[0098] Furthermore, the station cargo capacity and circulation efficiency constraints in step (4) are specifically:

[0099] 1) Ensure that the capacity of the incoming goods storage area, storage operation area and tallying and loading area meets the requirements. The expression is as follows:

[0100] (33)

[0101] In the formula, : Cargo capacity of optional facility j in functional area i; , , They respectively represent the minimum cargo capacity that must be met in the tallying and loading area, incoming cargo temporary storage area, and warehousing operation area.

[0102] 2) Ensure that the platform-station hall vertical handling area, the station hall-ground vertical handling area, and the incoming goods temporary storage area can meet the minimum cargo handling efficiency requirements, as expressed as follows:

[0103] (34)

[0104] In the formula, , , They represent the minimum cargo handling efficiency that must be met between platform and hall, hall and ground vertical handling area, and incoming cargo storage area respectively;

[0105] 3) Ensure that the unpacking and recycling area, sorting operation area, tallying and loading area, and pipeline connection area can meet the minimum cargo handling efficiency requirements, as expressed as follows:

[0106] (35)

[0107] In the formula, , , , They represent the minimum cargo handling efficiency that must be met in the unpacking and recycling area, sorting operation area, tallying and loading area, and pipeline connection area;

[0108] The budget constraint for station logistics space construction in step (4) is as follows:

[0109] 1) It is stipulated that the construction cost of the freight terminal hall of the station shall not exceed the budget, which is expressed as follows:

[0110] (36)

[0111] In the formula, : Budget for infrastructure construction of the freight terminal hall of the station;

[0112] 2) It is stipulated that the purchase and installation costs of various logistics operation facilities at the station shall not exceed the budget, as expressed as follows:

[0113] (37)

[0114] In the formula, : Budget for purchase and installation of station logistics facilities.

[0115] Furthermore, the two-level planning model of the shared station logistics space layout in step (5) is specifically as follows:

[0116] The original problem of subway station logistics space layout is decomposed into three interrelated optimization problems: unequal area facility layout problem UA-FLP, storage allocation problem SAP and obstacle avoidance Mann shortest path problem OAMSP; UA-FLP is set as the main problem, SAP and OAMSP are sub-problems, constraints and goals are reorganized, and the minimum cost bi-level programming model and maximum efficiency bi-level programming model for subway passenger and freight shared station layout are constructed respectively:

[0117] 1) The minimum cost two-level planning model for the layout of subway passenger and freight shared stations is constructed as follows:

[0118] Upper model UA-FLP model:

[0119] Objective function:

[0120] Constraints: equations (9) to (14), (16) to (19), (21) to (25), (29) to (30);

[0121] Lower model 1SAP model:

[0122] Objective function:

[0123] Constraints: formula (15), formula (20), formula (26)~(28), formula (33)~(35);

[0124] Lower layer model 2OAMSP model:

[0125] Constraints: Equations (31) to (32);

[0126] 2) The maximum efficiency double-layer planning model for the layout of subway passenger and freight shared stations is constructed as follows:

[0127] Upper model UA-FLP model:

[0128] Objective function:

[0129] Constraints: equations (9) to (14), (16) to (19), (21) to (25), (29) to (30), (36);

[0130] Lower model 1SAP model:

[0131] Objective function:

[0132] Constraints: formula (15), formula (20), formula (26)~(28), formula (33), formula (37);

[0133] Lower layer model 2OAMSP model:

[0134] Objective function:

[0135] Constraints: Equations (31) to (32);

[0136] In the formula, and They are the optimization objectives of the upper model of minimum cost and maximum efficiency respectively; and are the optimization objectives of the lower model 1 with minimum cost and maximum efficiency respectively; is the optimization target of the lower model 2; λ1, λ2, λ3 are the target correction coefficients.

[0137] Furthermore, step (6) solves the two-level planning model of the shared station logistics space layout as follows:

[0138] The allocation decision of logistics functional areas is generated and iterated by adaptive immune genetic algorithm to solve the upper model UA-FLP model, which includes the following steps:

[0139] Step 1: Algorithm preparation: input model parameters and algorithm parameters, and encode the main problem and sub-problems;

[0140] Step 2 Antigen identification: Treat the objective function and constraints of the upper model as antigens, extract and generate vaccines;

[0141] Step 3 Initialization: Let G = 1, and randomly generate an initial antibody population in the solution space of the upper model. Each antibody represents a feasible solution to the main problem.

[0142] Step 4: Extract vaccines: Extract vaccines based on prior knowledge;

[0143] Step 5 Genetic operation: Select the parent antibody and generate the offspring antibody through crossover and mutation operations;

[0144] Step 6 Vaccination operation: modify the value of the corresponding gene position of the antibody according to the value of the corresponding gene position in the vaccine, and update the offspring antibody;

[0145] Step 7: Conflict check: Check the validity of the newly generated antibodies and filter out antibodies that violate the model constraints;

[0146] Step 8 Clone selection: Determine the reproduction probability based on the evaluation results and select the antibodies for cloning;

[0147] Step 9 Antibody evaluation: Calculate the affinity between antibodies, antibody concentration, and affinity between antibodies and antigens, compare the affinity values ​​before and after vaccination, and evaluate the antibody quality;

[0148] Step 10 Solution synthesis: Decode each antibody in the current population to form N c The best solution to each sub-problem is obtained for each solution, and then combined with the solution to the main problem to obtain the complete solution of the model.

[0149] Step 11 Fitness evaluation and population update: Evaluate the fitness of the objective function, sort the new feasible solutions, and retain the top N p compose a new population and update it using the elite retention strategy;

[0150] Step 12 Termination condition: Determine whether the maximum number of iterations G has been reached max If yes, terminate the calculation and output the optimal solution; if no, return to Step 3 to continue iteration;

[0151] The immune antibodies generated by the main optimization program are decoded to obtain the functional area layout plan, which is synthesized with the solution fed back by the sub-optimization program, namely the facility allocation plan and the AGV path plan, to obtain a complete solution to the original problem; the solutions are ranked according to the fitness of the objective function; the overall fitness of the objective function of the minimum cost bi-level programming model and the maximum efficiency bi-level programming model for the layout of subway passenger and freight shared stations is expressed as and , as shown below:

[0152] (38)

[0153] (39);

[0154] In the formula, is the weight coefficient, and E is the depreciation coefficient of the subway station building.

[0155] Compared with the prior art, the present invention has the following significant advantages:

[0156] The present invention proposes a new subway station logistics functional area configuration method that integrates multiple cargo operations, which can collaboratively optimize the size, location, and quantity and distribution of logistics operation facilities in each functional area of ​​the station logistics functional area; the proposed shared station logistics space construction strategy, double-layer planning model, and multi-stage optimization procedure can effectively meet the large-scale, automated logistics operations of subway stations, while ensuring that the cargo circulation capacity of subway stations is met, and at the same time, the comprehensive configuration cost of the station freight terminal hall is minimized or the logistics processing capacity is maximized; at the same time, the present invention provides a method for reference based on the innovative use of underground space in subway stations, which helps to promote the transformation of urban logistics distribution to a three-dimensional transportation mode of "people on the ground, goods underground", so as to achieve the beneficial effects of alleviating urban traffic congestion, saving urban land resources, improving circulation economic efficiency, and promoting urban transportation.

[0157] The method proposed in the present invention more comprehensively considers the key decision of creating logistics space based on the underground space of subway stations, and proposes a set of configuration strategies, mathematical models and optimization algorithms based on the expansion of existing subway stations to form logistics functional areas. The proposed modeling and solution processes are easy to implement. Compared with previous experience-based station design ideas, the present invention considers new constraints and goals such as spatial gridding, minimum circulation capacity, construction budget, and transportation channels, and improves the layout rationality and economy of subway stations after adding logistics functions, without affecting passenger services. BRIEF DESCRIPTION OF THE DRAWINGS

[0158] Figure 1 This is a flow chart of the method for optimizing the configuration of logistics functional areas in a subway passenger and freight sharing station of the present invention.

[0159] Figure 2 This is the logistics space construction strategy for the subway passenger and freight shared station of the present invention.

[0160] Figure 3 It is a schematic diagram of the material handling process of the subway passenger and freight sharing station of the present invention.

[0161] Figure 4 This is a schematic diagram of the grid layout strategy of the subway passenger and freight sharing station of the present invention.

[0162] Figure 5 This is an example of internal facility selection and location allocation in the logistics functional area of ​​the present invention.

[0163] Figure 6 This is a schematic diagram of material handling path planning for a subway passenger and freight sharing station of the present invention.

[0164] Figure 7 This is a structural diagram of the double-layer planning model for the logistics space layout of the subway passenger and freight sharing station of the present invention.

[0165] Figure 8Schematic diagram of the operation of the adaptive improved immune genetic algorithm of the present invention; (a) in the figure is a crossover operation, and (b) in the figure is a mutation operation.

[0166] Fig. 9 1 is a diagram of the optimization result of the configuration of the logistics functional area of ​​a subway station in an embodiment of the present invention; (a) in the diagram is a minimum cost model, and (b) in the diagram is a maximum efficiency model. DETAILED DESCRIPTION

[0167] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0168] The present invention adopts the following technical solution: A method for optimizing the configuration of logistics functional areas in a subway passenger and freight sharing station, comprising the following steps:

[0169] (1) Determine the division method of logistics space in subway passenger and freight shared stations;

[0170] (2) Determine the functional areas and operation procedures of subway passenger and freight shared stations;

[0171] (3) Discretize the buildable area of ​​the freight hall of a subway passenger-freight shared station into a finite number of grids;

[0172] (4) Determine the internal facility selection and location of the logistics functional area of ​​the subway passenger and freight shared station;

[0173] (5) Calculate the material handling paths between logistics functional areas of subway passenger and freight shared stations;

[0174] (6) Establishing shape constraints for the logistics functional area of ​​subway passenger and freight shared stations;

[0175] (7) Establishing layout constraints for logistics functional areas of subway passenger and freight shared stations;

[0176] (8) Establish distance constraints for the functional areas of subway passenger and freight shared stations;

[0177] (9) Establish transportation channels and path constraints for subway passenger and freight shared stations;

[0178] (10) Establishing constraints on cargo capacity and circulation efficiency for subway passenger and freight sharing stations;

[0179] (11) Establish budget constraints for the construction of logistics space for subway passenger and freight shared stations;

[0180] (12) Establishing the objective function of the logistics space layout of subway passenger and freight shared stations;

[0181] (13) Construct a two-level planning model for the logistics space layout of subway passenger and freight shared stations;

[0182] (14) Execute adaptive immune genetic algorithm to solve the upper model;

[0183] (15) Execute the simulated plant growth algorithm and A* algorithm to solve the underlying model;

[0184] (16) Use models and algorithms to solve real-world subway station layout cases.

[0185] S1. Determine the division method of logistics space in subway passenger and freight shared stations.

[0186] Based on the design of the island platform subway station, the passenger platform is extended to form a cargo platform, which is used as a stopover platform for passenger and cargo trains or freight trains to support cargo loading and unloading. After the cargo is unloaded, it is immediately lifted to the logistics operation area (freight terminal) on the side of the passenger terminal hall by the shaft for centralized processing, without staying on the platform for too long. The freight terminal hall is equipped with logistics functional areas and facilities to process the arriving cargo. Finally, the cargo is lifted to the ground kiosk by the shaft or sent out through pipelines. The spatial construction strategy is as follows: Figure 2 shown.

[0187] S2. Determine the functional areas and operation procedures of subway passenger and freight sharing stations.

[0188] (1) Identify the loading and unloading operation area, platform-station hall vertical handling area, station hall-ground vertical handling area, incoming goods temporary storage area, unpacking and recycling area, warehousing operation area, sorting operation area, tallying and loading area, pipeline connection area, logistics management area, AGV channel and ground kiosk as the functional areas that need to be configured for subway station logistics operations.

[0189] (2) Design the material handling process of subway stations, such as Figure 3 As shown in the figure, the station receives goods sent from the upstream logistics park along the subway line to the loading and unloading operation area, and loads and unloads the goods; the goods are transported by AGV; then the goods are classified and stored in the incoming goods temporary storage area, unpacking and recycling area, and warehousing operation area; the goods are then processed from standard transport units into deliverable forms (such as parcels, batch pallets, etc.) through the sorting operation area; finally, the cargo collection and terminal delivery services are provided to surrounding customers through the tallying and loading area, pipeline connection area and logistics management area, and the services of object storage, recycling and delivery are provided in conjunction with the station's ground kiosk facilities and underground logistics operation area.

[0190] S3. Discretize the buildable area of ​​the freight hall of the subway passenger and freight shared station into a finite number of grids.

[0191] The plane space available for logistics operations in the shared station hall is regarded as a grid of equal size and closely arranged. By clarifying the occupancy status of each grid, the precise positioning of each functional area in the overall space is determined. The present invention regards each functional area as a rectangle, with a length and width that are both integer multiples of the grid side length. Sufficient space must be reserved between functional areas as cargo handling channels, such as Figure 4 shown.

[0192] S4. Determine the internal facility selection plan and location of the logistics functional area of ​​the subway passenger and freight shared station.

[0193] Based on the improved elastic zone architecture, the location of the operating facilities within the station logistics functional area is determined, such as Figure 5 As shown, a length of L M , width W M The number of facilities to be arranged in the functional area is 2, 1, 4 and 1 respectively. Considering the aisle with width h, the functional area is divided into 4 zones (Bays). Bay 1 is designated to accommodate two Class A facilities with a width equal to the width of Class A facilities (w A ), length is 2l A +h, it can be obtained that the width of Bay 2 and the height of Bay 3 can accommodate 2 Class C facilities and 1 Class B facility respectively. Two facilities C are selected for layout, and the width of Bay 3 is further set to be equal to the width of the Class B facility. Finally, the range of Bay 4 is obtained, and the remaining 1 facility D and two facilities C are arranged in it.

[0194] S5. Calculate the material handling paths between logistics functional areas of subway passenger and freight sharing stations.

[0195] The shortest length of the obstacle avoidance path between two points is used to calculate the actual material handling distance. Figure 6 As shown, it is stipulated that goods can only move vertically or horizontally on the arranged AGV channels and must avoid the internal facilities of other functional areas.

[0196] S6. Establish the shape constraints of the shared station logistics functional area according to equations (9) to (14).

[0197] S7. Establish the layout constraints of the shared station logistics functional area according to equations (15) to (20).

[0198] S8. Establish the distance constraints of the shared station logistics functional area according to equations (21) to (28).

[0199] S9. Establish the transportation channels and path constraints of the shared station logistics functional area according to equations (29) to (32).

[0200] S10. Establish the capacity and circulation efficiency constraints of the shared station logistics functional area according to equations (33) to (35).

[0201] S11. Establish the budget constraints for the construction of shared station logistics space according to equations (36) to (37).

[0202] S12. According to formulas (1) to (8), six objective function components are established, namely, the construction cost of the logistics space of the subway passenger and freight shared station, the installation and maintenance cost of the station logistics operation facilities, the objective function of the cargo handling distance within the station, the station cargo circulation capacity, and the aggregation degree of the station logistics functions.

[0203] S13. Construct a two-level planning framework to transform the original problem into interrelated upper and lower level problems, also known as the main problem and sub-problems, each of which has its own objective function and constraints. The objective function of the main problem depends on the optimal solution of the sub-problem, and the optimal solution of the sub-problem is affected by the decision variables of the main problem. Through iterative solution and interaction between the upper and lower levels, convergence is finally achieved.

[0204] In the present invention, the subway station logistics space layout problem is decomposed into the unequal area facility layout problem (UA-FLP), the storage allocation problem (SAP) and the obstacle avoiding Mann shortest path problem (OAMSP). UA-FLP is set as the main problem, and the minimum cost bi-level programming model and the maximum efficiency bi-level programming model of the subway passenger and freight shared station logistics space layout are respectively constructed, and SAP and OAMSP are set as two sub-problems of the bi-level programming model. Sub-problem 1 aims at the minimum weighted facility installation and operation cost and the maximum station cargo circulation efficiency respectively; Sub-problem 2 further solves the shortest obstacle avoiding path between facilities according to the facility configuration obtained in sub-problem 1. The structure diagram of the bi-level programming model is shown in the figure. Figure 7 shown.

[0205] S14, execute the adaptive immune genetic algorithm to solve the upper model, the specific process is as follows:

[0206] (1) Model encoding and decoding operations:

[0207] Each individual (i.e., antibody) in the population is represented by a real number matrix A. The first number (i.e., the first gene position) of each row (i.e., a chromosome) of the matrix represents the number of the functional area category; the values ​​of the second and third gene positions of each chromosome represent the grid numbers of the center point of the functional area along the X and Y directions respectively; the values ​​of the fourth and fifth gene positions represent the number of grid units occupied by the functional area along the X and Y directions respectively; all functional area layout decision information is encoded into the antibody through gene assignment.

[0208] The antibody chromosome is converted into a binary matrix B through decoding. The converted matrix B is divided into three gene groups, which represent the functional area category, the X-direction grid allocation, and the Y-direction grid allocation. Through the combination of genes, all functional areas can be located and the site layout can be drawn. The unoccupied grid cells in the plannable site are marked as AGV channel areas.

[0209] (2) Genetic operation:

[0210] The selected parent chromosomes are paired, and r chromosomes are determined from the parent 1 individual according to the crossover probability, and the crossover operation is performed with the chromosomes with the same functional area category coding in the parent 2 individual. Through the above exchange, the offspring chromosomes are obtained. Finally, the offspring chromosomes with different virtual positions are combined with other unexchanged genes of the parent 1 and the parent 2 to form the complete coding of the offspring individual 1 and the individual 2.

[0211] The first gene position values ​​of the two sets of chromosomes of an individual are swapped, which means that the positions of different functional regions are swapped. On the other hand, for a certain chromosome, the 4th and 5th gene position values ​​are swapped with random probability, which means that the functional region is rotated 90 degrees on the plane, such as Figure 8 shown.

[0212] Adaptive crossover and mutation strategies are used to control genetic operations. The calculation method of crossover probability and mutation probability is as follows:

[0213] (40);

[0214] (41) ;

[0215] In the formula, p c : crossover probability; p m : Mutation probability; P G : updated population; g: P G Any antibody in E x (P G ): information entropy of the x-th gene; E(P G ): P G The average entropy of S(P G ): population similarity.

[0216] (3) Vaccination operation:

[0217] Gene loci are extracted from the current best and historical best antibodies and vaccines are produced; antibodies to be vaccinated are selected from the parent population, and one or more gene fragments are selected according to the roulette wheel method to produce new antibodies by replacing the gene code values.

[0218] (4) Antibody evaluation:

[0219] First, the antibody affinity between antibody u and antibody v is calculated, and the expression is as follows:

[0220] ; ; (42) ;

[0221] In the formula, AY uv: Antibody affinity between antibody u and antibody v; H uv (n): information entropy of antibody u and antibody v, H uv (n) = 0 means that all genes of the two antibodies are the same; H i (n): information entropy of the ith gene position of the nth antibody; s: the number of optional gene values ​​for each gene position; p ij : The probability that a gene value j among s optional gene values ​​appears at gene position i; m: The number of gene positions where each antibody exists; L: The length of the antibody.

[0222] Second, calculate the antibody concentration:

[0223] (43);

[0224] Where, C u : the concentration of antibody u; Q: the pre-set threshold, when AY uv When AY is greater than Q, uv =1 if the value is set to 0, otherwise it is 0.

[0225] Finally, the affinity of the antibody to the antigen:

[0226] (44);

[0227] Where AX uw : affinity of antibody u (solution) to antigen w (target); d uw : The difference between antibody u and antigen w; r uw : The number of gene loci at which the antibody and antigen differ.

[0228] (5) Clone selection operation:

[0229] The incentive degree of the antibody is calculated using a roulette-based selection strategy as follows:

[0230] (45);

[0231] Where P u ∈(0,1) represents the excitation degree of antibody u; δ∈(0,1) is the adjustment factor.

[0232] According to the number of antibodies, the roulette wheel is divided into N sectors for random selection, and the selected antibodies are cloned. The area of ​​each sector is the incentive value of the population antibody.

[0233] (6) Scheme synthesis and population update:

[0234] Decode the immune antibodies generated by the main optimization program, obtain the functional area layout plan, and synthesize it with the solution fed back by the sub-optimization program to obtain the complete solution (i.e., complete antibody) of the model constructed by the present invention. Compare the best feasible solution (corresponding to the current optimal objective function) with the individuals in the memory bank. If it is greater than its fitness, replace the corresponding worst individual. In order to avoid the loss of effective genes, each time the memory bank is updated, the top 10% individuals with the highest fitness are first stored in the memory bank. Finally, according to the expected reproduction probability, the remaining excellent individuals in the group are stored in the memory bank to achieve population update.

[0235] S15. Solve the lower model by simulating plant growth algorithm and A* algorithm.

[0236] (1) Execute the simulated plant growth algorithm to generate the best solution for the internal facilities of each functional area, which includes the following steps:

[0237] Step 1 (initialization): Encode the decision to be optimized, randomly generate the initial growth point X0 as the root node of plant growth under the premise of following relevant constraints, and calculate the objective function f(X0) of the initial growth point. Let the initial values ​​of the optimal configuration solution and the optimal objective function be x best = X0, f(x best ) = f(X0). Determine the length of the plant trunk, the maximum number of plant branches, and the maximum number of growth times K max .

[0238] Step 2 (grafting growth operation): remember is the k-th generation solution set X k The growth point α in In the gene sequence of Select n k Genes are grafted and grown to generate a set of new growth points. First, new growth points are generated by exchanging gene positions, that is, based on the original growth point, the second gene position value of the facility gene fragment is exchanged to achieve the exchange of the number of facilities of different specifications. Further, starting from gene fragment 3, several gene fragments are randomly selected to increase or decrease the random step length of the second gene value. Through the above two steps, the original branch X k Each growth point is grafted to obtain a new growth point and generate a new plant branch X k+1 (New interpretation collection).

[0239] Step 3: For each new growth point x obtained k+1 , calculate the objective function value, and eliminate the target value lower than the historical target value f(x best ) of the growth point, add the new growth point that is retained to the set, and update f(x best ).

[0240] Step 4 (Calculate morphogen concentration): Calculate the morphogen concentration of all retained growth points. The expression is as follows:

[0241] (46);

[0242] In the formula, is the morphogen concentration at the growth point α during the k+1th growth, is the objective function value of the growth point α during the k+1th growth, and λ represents the number of growth points during the k+1th growth.

[0243] Step 5: Set a probability space of [0, 1], which is filled with the morphogen concentration norms of all retained growth points. Generate a certain number of random decimals. If a decimal point falls on In the corresponding interval, Selected as new growth point.

[0244] Step 6: Repeat Step 2 to Step 5 until no new growth points are generated or the maximum growth number K is reached. max . Output the best solution and objective function of the lower layer model 1, and feed back the encoded information for the next stage of optimization.

[0245] (2) Using the A* algorithm to obtain the shortest path for cargo flow under the functional area and facility layout decision, the following steps are included:

[0246] Step 1: Set the freight terminal site information and facility location;

[0247] Step 2: Set the starting point and destination of the path to be searched, and add the starting position to the open list;

[0248] Step 3: Select the node with the lowest cost from the open list as the current position. When the current position node is added to the closed list, its record in the open list is deleted;

[0249] Step 4: During the search process, stop searching when any of the following conditions are met: 1) The target location has been added to the closed list, which means that the shortest path to avoid obstacles has been found; 2) The open list is empty and the target location has not been found, which means that there is no reachable path;

[0250] Step 5: Return to Step 2 and set a new search starting point and destination again until all the shortest obstacle-avoiding paths for all cargo flows in the OD matrix are found;

[0251] S16. Use the model and algorithm to solve the real subway station case and execute the simulation program. The steps are as follows:

[0252] (1) Set up the case scenario: including the original subway station layout; subway station construction boundaries; logistics operation area dimensions; freight train parameters and grid division of the plannable area;

[0253] (2) Set the number of functional areas of the two models and set the model parameters;

[0254] (3) Setting algorithm parameters: including the number of main program iterations; the maximum number of plant growth times; population size; memory bank capacity; antibody concentration threshold; antibody excitation adjustment factor; initial crossover probability and mutation probability;

[0255] (4) Analysis of simulation results: including analysis of model optimization results, analysis of station logistics functional area configuration under the goals of minimum cost and maximum efficiency, visualization analysis of station layout plans, and analysis of facility selection plans.

[0256] Example

[0257] The original layout of the subway station is that the platform layer and the station hall layer overlap vertically, and the left edge of the passenger platform is aligned with the leftmost wall of the passenger hall, forming the left edge of the station building. In this embodiment, it is considered to use the underground space on the left side of the original station to build a logistics space, extend the passenger platform to the left by about 70 meters, keep the width unchanged, build an island freight platform in the middle of the upper and lower track areas, and form a freight station hall by expanding the left area of ​​the original passenger hall layer.

[0258] The maximum constructible length of the station freight terminal along the X and Y directions is set to 96 meters and 48 meters respectively, and the area is divided into 1 meter × 1 meter grid units. A total of 4608 grids can be used to arrange the logistics functional area.

[0259] Any CTU is considered as a cube with a side length of 1 meter. The length and width of the functional area must be an odd multiple of the number of grids.

[0260] The model and algorithm proposed in the present invention are applied to the embodiment, and 18 functional areas of various types are set and arranged: platform-station hall vertical transfer area: 1; station hall-platform vertical transfer area: 1; incoming goods temporary storage area: 3; unpacking and recycling area: 3; storage operation area: 3; sorting operation area: 2; tallying and loading area: 3; pipeline connection area: 1; logistics management area (fixed as 7 m×12 m): 1.

[0261] The algorithm parameters are set as follows: The number of main program iterations G max =300; Maximum number of plant growth K max =50; Population size Pop=100; Memory bank capacity P r =50; antibody concentration threshold Q=0.55; antibody excitation adjustment factor δ=0.25; initial crossover probability =0.8; initial mutation probability =0.2.

[0262] Combined with the model and algorithm proposed in this invention, numerical simulation is carried out to obtain the optimization results of the logistics space layout of subway passenger and freight sharing stations under the minimum cost target and maximum efficiency target as shown in Table 1. The layout scheme is visualized as shown in Fig. 9 The results show that the construction cost of the freight terminal hall output by the minimum cost model is 51.03 million yuan, which saves 27.1% compared with the maximum capacity model. The actual layout area of ​​the freight terminal hall under the minimum cost target is 3402 square meters, which is equivalent to 74% of the maximum buildable area. The efficiency-oriented optimal layout scheme reflects more advantages in cargo handling capacity, and the station cargo circulation efficiency is 24.6% higher than the cost-optimal layout scheme.

[0263] Table 1 Comparison of optimization results of the embodiments

[0264] Optimization results Minimum cost model Maximum Capacity Model Total target value 1520.24 (yuan / day) 3756.18 (units / hour) Facility acquisition cost (ten thousand yuan) 653.48 896.16 Facility operation and maintenance cost (yuan / day) 830.81 1115.04 Construction cost of freight terminal hall (10,000 yuan) 5103 6486 Station cargo flow capacity (pieces / hour) 2408 (units) or 19264 (bulk) 3192 (units) or 25536 (bulk) Total cargo capacity of the station (pieces / hour) 3984 (unit), 4020 (bulk) 5512 (unit), 6080 (bulk) Length of freight terminal hall (m) 81 90 Freight terminal building width (m) 42 47 <![CDATA[Actual construction area of the freight station hall (m 2 ).]]> 3402 4230 <![CDATA[Occupied area of logistics facilities (m 2 )]]> 1492 2038 <![CDATA[Public area AGV passage area (m 2 )]]> 1281 1335 <![CDATA[Internal passage area occupied in the functional area (m 2 )]]> 629 857 Total number of facilities 126 135

[0265] A result obtained by simulation of the embodiment shows that the layout scheme oriented to the minimum cost tends to select more facilities with "smaller area and higher processing capacity", thereby reducing the functional area required to meet the minimum capacity requirements. This strategy significantly reduces the construction cost of the freight station hall at the expense of increasing the cost of purchasing facilities. The layout scheme under the goal of maximum cargo circulation efficiency can improve the cargo handling efficiency of various logistics functional areas of the station as a whole, and the configuration gap of cargo handling capacity of each functional area is only 1.99%, ensuring that the cargo arriving at the station can be smoothly processed through each link. The functional area difference in the maximum efficiency layout scheme is smaller, and the number of facilities of different models is more evenly distributed, which is conducive to alleviating the negative impact of facility failure on the overall freight capacity of the station. In summary, the method proposed in the present invention can optimize the configuration and layout of various logistics functional areas and related facilities of subway passenger and freight sharing stations according to different goal orientations, so as to improve the economy and operation capacity of the construction of subway passenger and freight sharing stations.

Claims

1. A method for optimizing the configuration of logistics functional areas in a subway passenger and freight sharing station, characterized in that: The steps include: Step (1): Formulate a logistics space construction strategy for a non-transfer underground double-deck island station, including a strategy for dividing passenger and freight operation spaces in the subway station and setting up logistics functional areas that need to be configured; Step (2): Set up a shared station logistics space modeling strategy, including the setting of subway station logistics space grid units, the internal facility positioning and matching strategy of the logistics functional area, and the calculation method of the material handling distance of the functional area; Step (3): Establish the objective function and decision variables of the shared station logistics space layout, including the objective function of minimizing the station logistics space construction cost, the objective function of minimizing the station logistics operation facility installation and maintenance cost, the objective function of minimizing the cargo handling distance within the station, the objective function of maximizing the station cargo circulation capacity, and the objective function of maximizing the station logistics function aggregation degree; Step (4): Establish shared station logistics space layout constraints, including functional area shape constraints, functional area layout constraints, functional area distance constraints, transportation channel and path constraints, station cargo capacity and circulation capacity constraints, and station logistics space construction budget constraints; Step (5): Construct a two-level planning model for the shared station logistics space layout; Step (6): Solve the two-level planning model for the shared station logistics space layout.

2. The method according to claim 1, characterized in that The specific strategy for dividing the passenger and freight operation space of the subway station in step (1) is as follows: Relying on the station hall space station to complete the internal logistics operations, the station platform is equipped with a cargo platform for trains to stop and load and unload. After the cargo is unloaded on the platform, it is lifted to the logistics operation area on the station hall for centralized processing. Finally, the cargo is lifted to the ground cargo kiosk at the station exit by using the vertical shaft or sent out through the secondary underground pipeline. The logistics functional areas in step (1) specifically include: ① Loading and unloading operation area: that is, the station freight platform, which provides a loading and unloading platform for subway freight trains; ② Platform-station hall vertical handling area: automatically lift the arriving goods to the station hall level through the lifting shaft, and at the same time lower the empty freight units to the platform level for recovery with the train; ③ Station hall-ground vertical handling area: lift the processed goods to the external ground space through the lifting shaft; ④ Incoming goods temporary storage area: provide classification, queuing, stacking and cross-handling places for station hall goods; ⑤ Unpacking and recycling area: split the freight units transported by the subway, take out the goods and hand them over to the sorting facilities; ⑥ Warehousing operation area: provide storage space for goods or freight units that are not delivered immediately; ⑦ Sorting operation area: pack the express parcels according to the delivery destination; complete the disassembly of the pallet Picking and distribution of various types of bulk goods;⑧ Cargo sorting and loading area: marking, checking, packaging and loading of completed goods, classifying goods according to distribution form, quantity and transportation capacity, determining delivery priority and loading vehicle number;⑨ Pipeline connection area: organizing the site for terminal underground logistics, providing space for capsule vehicles to load and unload goods, dispatch and dock;⑩ Logistics management area: operating and managing station logistics business;⑪ Automatic guided vehicle AGV channel: arranging channels for AGV to travel between various functional areas of the subway station freight terminal;⑫ Ground kiosk: storing goods lifted from the inside of the station, serving as a place for pedestrians to pick up and deliver goods.

3. The method according to claim 2, characterized in that The specific grid unit settings for the subway station logistics space in step (2) are as follows: The plane space of the station hall used for logistics operations is regarded as a grid of equal size and closely arranged, and the position of each functional area in the space is located by specifying the occupancy relationship of the plane grid; The specific strategy for the internal facility positioning and selection of the logistics functional area in step (2) is as follows: Considering the three mutually constrained variables of facility cost, occupied space and performance parameters, the operating facilities are selected; based on the zone architecture strategy with added zone directional decision, the internal facilities of the logistics functional area of ​​the subway station are arranged to meet the following rules: 1) The shape of any optional facility is rectangular; 2) The length and width of any optional facility are integer multiples of the grid side length; 3) The vertices of the arranged facilities must coincide with the vertices of the grid; 4) Gaps should be reserved between the facilities to realize internal cargo handling; The specific calculation method for the material handling distance of the functional area in step (2) is: The cargo handling process of the shared station is transformed into a type of obstacle-avoiding Mann shortest path problem, and the shortest obstacle-avoiding cargo handling path in the venue is obtained by solving the problem. The transport path is calculated using the actual transport distance, requiring that the goods can only move vertically or horizontally on the arranged AGV channel and must avoid internal facilities in other functional areas.

4. The method according to claim 3, characterized in that The objective function of the station logistics space construction cost in step (3) minimizes the station construction cost, specifically: Min (1) Where, SP: freight terminal hall construction area, that is, the sum of the areas of each logistics functional area and AGV channel; c s : Construction cost of underground space per grid area of ​​the station; CO 建造 : Construction cost of freight terminal hall infrastructure; : grid cell side length; I: the set of logistics functional areas of subway stations, indexed by i; M: The set of serial numbers of the plannable area grid of the freight terminal hall arranged along the X direction, with m as the index; N: The set of serial numbers of the plannable area grid of the freight terminal hall arranged along the Y direction, with n as the index; : 0-1 decision variable, when the grid with coordinates (m, n) is assigned to functional area i, the value is 1, otherwise it is 0; : 0-1 indicator variable, when the grid with coordinates (m, n) is used to arrange the AGV channel, the value is 1, otherwise it is 0; The objective function of the station logistics operation facility installation and maintenance cost in step (3) minimizes the station logistics facility cost, specifically: （2） （3） In the formula, CO 购置 :Procurement and installation costs of logistics-related facilities, depreciation to daily basis; CO 运维 : Daily operation and maintenance costs of facilities; J i : The set of optional operating facilities for functional area i, with j as index; : The purchase and installation cost of optional facility j in functional area i; : The number of installation facilities j in functional area i; : The service life of optional facility j in functional area i, calculated in days; : Operation and maintenance cost of optional facility j in functional area i, per day; The objective function of the intra-station cargo handling distance in step (3) minimizes the intra-station cargo handling distance, specifically: （4） Where, CD (i, i'): the shortest obstacle avoidance distance between the center of functional area i and the center of functional area i'; : Binary indicator variable, if the cargo flow path from the center of functional area i1 to the center of functional area i2 passes through grid (m, n), the value is 1, otherwise it is 0; , : Binary indicator variable, if functional area i1, i2 is arranged in the freight terminal hall, the value is 1, otherwise it is 0.

5. The method according to claim 4, characterized in that The objective function of the station freight flow capacity in step (3) maximizes the station freight flow capacity, specifically: （5） In the formula, CV 流通 : The freight flow capacity of the subway station; CV B2-B1 、CV B1-地面 、CV 暂存 Respectively represent the cargo handling efficiency of the platform-station hall vertical handling area, the station hall-ground vertical handling area, and the incoming goods temporary storage area; CV 拆箱 、CV 分拣 、CV 理货 、CV 接驳 They represent the cargo handling efficiency of the unpacking and recycling area, the sorting operation area, the tallying and loading area, and the pipeline connection area, respectively. The expressions are as follows: （6） In the formula, : Conversion factor between freight units and bulk cargo in subway transportation; : The number of goods that can be processed in parallel by optional facility j in functional area i; : The processing efficiency of optional facility j in functional area i, hours; : Binary indicator variable, if the functional area i is the platform-station hall vertical transfer area, the value is 1, otherwise it is 0; : Binary indicator variable, if the functional area i is the station hall-ground vertical handling area, the value is 1, otherwise it is 0; : Binary indicator variable, if the functional area i is the pipeline connection area, the value is 1, otherwise it is 0; : Binary indicator variable, if functional area i is a temporary storage area for incoming goods, the value is 1, otherwise it is 0; : Binary indicator variable, if functional area i is a box unpacking recycling area, the value is 1, otherwise it is 0; : Binary indicator variable, if functional area i is the sorting operation area, the value is 1, otherwise it is 0; : Binary indicator variable, if functional area i is the tally loading area, the value is 1, otherwise it is 0; The objective function of the station logistics function aggregation degree in step (3) maximizes the station logistics function aggregation degree, specifically: （7） Where, CR: aggregation degree of station logistics function; : Binary indicator variable, if functional area i is arranged in the freight terminal hall, the value is 1, otherwise it is 0; R i : The aggregation degree of functional area i and all its extremely strong / strong / relatively strong correlation level functional areas, the expression is as follows: （8） In the formula, : Binary indicator variable, if functional area i and functional area i' are extremely strongly associated, strongly associated or relatively strongly associated, the value is 1, otherwise it is 0.

6. The method according to claim 5, characterized in that The functional area shape constraints in step (4) specifically include: 1) Specify the spatial shape of the freight terminal hall, grid unit division, and positioning functional areas to ensure that the plane grid occupied by the logistics space of each functional area is a complete and regular rectangle. The expression is as follows: （9） （10） 2) The slenderness ratio of any logistics functional area is required not to exceed the set range. The expression is as follows: （11） In the formula, : The maximum allowable slenderness ratio of functional area i; , Respectively represent the number of grid cells occupied by functional area i in the X and Y directions; 3) The shape of the freight terminal hall is required to be rectangular, that is, the number of plane grids distributed along any X row or Y column is equal, and the expression is as follows: （12） （13） 4) The geometric center of any functional area must be located at the geometric center of a grid, that is, the edge of any functional area must be composed of an odd number of grid cells. The expression is as follows: （14）； The functional area layout constraints in step (4) are as follows: 1) Specify the number of functional areas, the layout range, and the internal facility layout requirements of the functional areas. Except for the logistics management area, each functional area is equipped with at least one set of corresponding operating facilities. The expression is as follows: （15） In the formula, : Binary indicator variable, if zone i is a logistics management zone, the value is 1, otherwise it is 0; 2) A unique vertical handling area is arranged between the cargo platform B2 layer and the cargo terminal hall B1 layer, as well as between the cargo terminal hall and the ground. At the same time, the cargo terminal hall is equipped with a unique pipeline connection area and logistics management area. The number of other functional areas arranged is not less than 1, and the expression is as follows: （16） （17） In the formula, : Binary indicator variable, if area i is a storage operation area, the value is 1, otherwise it is 0; 3) The layout range of the platform-station hall vertical handling area, the station hall-ground vertical handling area, and the pipeline connection area is specified as follows: （18） （19） In the formula, (m1, m2) and (n1, n2) represent the grid numbers corresponding to the areas that can be arranged in the platform-station hall vertical handling area in the X and Y directions respectively; (m3, m4) and (n3, n4) represent the grid numbers corresponding to the areas that can be arranged in the station hall-ground vertical handling area in the X and Y directions respectively; (m5, m6) and (n5, n6) represent the grid numbers corresponding to the areas that can be arranged in the pipeline connection area in the X and Y directions respectively; 4) Ensure that relevant operation facilities can be configured only after the functional area has been constructed. The expression is as follows: （20）。 7. The method according to claim 6, characterized in that The functional area distance constraint in step (4) is as follows: 1) Limit the distance between functional areas and facilities to ensure that the projection distance between the two most adjacent functional areas in the X and Y directions, including the AGV channel, does not exceed the construction length and width of the freight terminal hall, and the sum of the area of ​​each functional area and the area of ​​the AGV channel does not exceed the construction area of ​​the freight terminal hall. The expression is as follows: （21） （22） （23） In the formula, : The projection distance and grid number between the center of functional area i1 and the center of functional area i2 along the Y direction; : The projection distance between the center of functional area i1 and the center of functional area i2 along the X direction, the number of grids; L: The maximum allowable construction length of the freight terminal hall in the X direction, the number of grids; W: The maximum allowable construction width of the freight terminal hall in the Y direction, the number of grids; 2) Ensure that any functional area i1 does not overlap or interfere with any functional area i2. The expression is as follows: （24） Where, g2: the minimum allowable distance between any two functional areas; 3) Ensure that the functional area to be arranged must be one of the nine logistics functional areas of the freight terminal hall, as expressed as follows: （25） 4) Ensure that there is no interference between the internal facilities of any functional area. The facilities must maintain a set distance. The length, width and sum of all horizontal and vertical distances of the configured facilities shall not exceed the length and width of the functional area. The expression is as follows: （26） （27） 5) Ensure indicator variables , and Consistent with the meaning of the decision variables, the expression is as follows: （28） Where: : Binary indicator variable, which is 1 if the nth row of grid horizontally passes through facility j installed in functional area i, otherwise it is 0; : Binary indicator variable, which is 1 if the mth row of grid vertically passes through facility j installed in functional area i, otherwise it is 0; The specific transport channel and path constraints in step (4) are: 1) Ensure that the AGV channel is adjacent to each functional area. The expression is as follows: （29） 2) Ensure that there is no overlap or interference between the logistics functional area and the AGV channel. The expression is as follows: （30） 3) It is stipulated that cargo handling can only be carried out when the grid is assigned to the AGV channel. The expression is as follows: （31） In the formula, : Binary indicator variable, if the cargo flow path from the center of functional area i1 to the center of functional area i2 passes through grid (m, n), the value is 1, otherwise it is 0; 4) Ensure that the cargo flow paths between functional areas do not pass through the obstacle area, that is, the grid area occupied by facilities. The expression is as follows: （32） In the formula, : Binary indicator variable, the value is 1 if grid (m, n) is occupied by facility j in functional area i, otherwise it is 0.

8. The method according to claim 7, characterized in that The station cargo capacity and circulation efficiency constraints in step (4) are as follows: 1) Ensure that the capacity of the incoming goods storage area, storage operation area and tallying and loading area meets the requirements. The expression is as follows: （33） In the formula, : Cargo capacity of optional facility j in functional area i; , , They represent the minimum cargo capacity that must be met in the tallying and loading area, incoming cargo storage area, and warehousing operation area; 2) Ensure that the platform-station hall vertical handling area, the station hall-ground vertical handling area, and the incoming goods temporary storage area can meet the minimum cargo handling efficiency requirements, as expressed as follows: （34） In the formula, , , They represent the minimum cargo handling efficiency that must be met between platform and hall, hall and ground vertical handling area, and incoming cargo storage area respectively; 3) Ensure that the unpacking and recycling area, sorting operation area, tallying and loading area, and pipeline connection area can meet the minimum cargo handling efficiency requirements, as expressed as follows: （35） In the formula, , , , They represent the minimum cargo handling efficiency that must be met in the unpacking and recycling area, sorting operation area, tallying and loading area, and pipeline connection area; The budget constraint for station logistics space construction in step (4) is as follows: 1) It is stipulated that the construction cost of the freight terminal hall of the station shall not exceed the budget, which is expressed as follows: （36） In the formula, : Budget for infrastructure construction of the freight terminal hall of the station; 2) It is stipulated that the purchase and installation costs of various logistics operation facilities at the station shall not exceed the budget, as expressed as follows: （37） In the formula, : Budget for purchase and installation of station logistics facilities.

9. The method according to claim 8, characterized in that The two-level planning model of the shared station logistics space layout in step (5) is as follows: The original problem of subway station logistics space layout is decomposed into three interrelated optimization problems: unequal area facility layout problem UA-FLP, storage allocation problem SAP and obstacle avoidance Mann shortest path problem OAMSP; Set UA-FLP as the main problem, SAP and OAMSP as sub-problems, reorganize constraints and objectives, and construct the minimum cost bi-level programming model and maximum efficiency bi-level programming model for the layout of subway passenger and freight shared stations respectively: 1) The minimum cost two-level planning model for the layout of subway passenger and freight shared stations is constructed as follows: Upper model UA-FLP model: Objective function: , Constraints: equations (9) to (14), (16) to (19), (21) to (25), (29) to (30); Lower model 1SAP model: Objective function: , Constraints: formula (15), formula (20), formula (26)~(28), formula (33)~(35); Lower layer model 2OAMSP model: , Constraints: Equations (31) to (32); 2) The maximum efficiency double-layer planning model for the layout of subway passenger and freight shared stations is constructed as follows: Upper model UA-FLP model: Objective function: , Constraints: equations (9) to (14), (16) to (19), (21) to (25), (29) to (30), (36); Lower model 1SAP model: Objective function: , Constraints: formula (15), formula (20), formula (26)~(28), formula (33), formula (37); Lower layer model 2OAMSP model: Objective function: , Constraints: Equations (31) to (32); In the formula, and They are the optimization objectives of the upper model of minimum cost and maximum efficiency respectively; and are the optimization objectives of the lower model 1 with minimum cost and maximum efficiency respectively; is the optimization target of the lower model 2; λ1, λ2, λ3 are the target correction coefficients.

10. The method according to claim 9, characterized in that Step (6) solves the two-level planning model of shared station logistics space layout as follows: The allocation decision of logistics functional areas is generated and iterated by adaptive immune genetic algorithm to solve the upper model UA-FLP model, which includes the following steps: Step 1: Algorithm preparation: input model parameters and algorithm parameters, and encode the main problem and sub-problems; Step 2 Antigen identification: Treat the objective function and constraints of the upper model as antigens, extract and generate vaccines; Step 3 Initialization: Let G = 1, and randomly generate an initial antibody population in the solution space of the upper model. Each antibody represents a feasible solution to the main problem. Step 4: Extract vaccines: Extract vaccines based on prior knowledge; Step 5 Genetic operation: Select the parent antibody and generate the offspring antibody through crossover and mutation operations; Step 6 Vaccination operation: modify the value of the corresponding gene position of the antibody according to the value of the corresponding gene position in the vaccine, and update the offspring antibody; Step 7: Conflict check: Check the validity of the newly generated antibodies and filter out antibodies that violate the model constraints; Step 8 Clone selection: Determine the reproduction probability based on the evaluation results and select the antibodies for cloning; Step 9 Antibody evaluation: Calculate the affinity between antibodies, antibody concentration, and affinity between antibodies and antigens, compare the affinity values ​​before and after vaccination, and evaluate the antibody quality; Step 10 Solution synthesis: Decode each antibody in the current population to form N c The best solution to each sub-problem is obtained for each solution, and then combined with the solution to the main problem to obtain the complete solution of the model. Step 11 Fitness evaluation and population update: Evaluate the fitness of the objective function, sort the new feasible solutions, and retain the top N p compose a new population and update it using the elite retention strategy; Step 12 Termination condition: Determine whether the maximum number of iterations G has been reached max If yes, terminate the calculation and output the optimal solution; if no, return to Step 3 to continue iteration; The immune antibodies generated by the main optimization program are decoded to obtain the functional area layout plan, which is synthesized with the solution fed back by the sub-optimization program, namely the facility allocation plan and the AGV path plan, to obtain a complete solution to the original problem; the solutions are ranked according to the fitness of the objective function; the overall fitness of the objective function of the minimum cost bi-level programming model and the maximum efficiency bi-level programming model for the layout of subway passenger and freight shared stations is expressed as and , as shown below: （38） （39） In the formula, is the weight coefficient, and E is the depreciation coefficient of the subway station building.

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