Method and system for evaluating whole life cycle cost of subway freight system under passenger and freight cooperation

Abstract

The invention discloses a method and a system for evaluating the life cycle cost of a subway freight system under passenger and freight collaboration. The method comprises the following steps: constructing a life cycle cost model of the subway freight system under passenger and freight collaboration, wherein the life cycle cost model comprises four stages of decision design, construction, operation maintenance and scrap recovery; determining a key cost factor influencing the cost of each stage of the subway freight system under the whole life cycle cost model, and constructing a whole life cycle cost factor relation model of the subway freight system under passenger and freight cooperation based on each cost factor influence factor; and based on the whole-life-cycle cost motivation relationship model and the passenger and freight income of the subway freight system under passenger and freight collaboration, predicting and evaluating the minimization of the whole-life-cycle cost or the maximization of the benefit of the subway freight system under passenger and freight collaboration. By constructing a cost calculation framework and model, key cost causes are identified and quantified, and accurate evaluation and effective management of the M-ULS cost are realized.

Description

Technical Field

[0001] This invention belongs to the field of urban rail transit logistics technology, specifically relating to a method and system for assessing the full life cycle cost of a subway freight system under passenger-freight coordination. Background Technology

[0002] With the unprecedented development of e-commerce, the demand for express delivery services in my country has been increasing by about 30% annually since 2012. To meet the surge in logistics demand, a large number of trucks, logistics stations, and couriers have emerged in cities, leading to increasingly prominent negative effects such as road congestion and environmental pollution. In the exploration of new freight models that can both improve logistics efficiency and alleviate environmental pressure, the Underground Logistics System (ULS) has been proposed and received widespread attention as an effective means to address the current constraints on urban transportation and logistics development. The Metro-based Underground Logistics System (M-ULS) has the potential to become a breakthrough point for the implementation of this new freight model.

[0003] However, with the rapid growth of urban logistics demand, traditional freight transport methods face problems such as traffic congestion and environmental pollution. Subway freight systems, as a new form of underground logistics technology, offer advantages such as full utilization of underground space, alleviating traffic pressure, and energy conservation and emission reduction. However, the collaborative operation mechanism of passenger and freight systems complicates cost structures, affecting the accuracy of benefit assessments. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method and system for evaluating the full life cycle cost of a subway freight system under passenger-freight coordination. By constructing a cost calculation framework and model, key cost drivers are identified and quantified, thereby achieving accurate evaluation and effective management of M-ULS costs.

[0005] To achieve the above objectives, the present invention is implemented using the following technical solution: On the one hand, this invention provides a method for evaluating the full life-cycle cost of a subway freight system under passenger-freight coordination, including the following steps: Step S1: Construct a full life cycle cost model for a subway freight system under passenger-freight coordination, including four stages: decision-making and design, construction, operation and maintenance, and decommissioning and recycling. Step S2: Identify the key cost drivers affecting the cost of each stage of the metro freight system under the life-cycle cost model, including network scale, network layout, construction technology, process operation, and stakeholder collaboration. And to construct a full life-cycle cost driver relationship model for the subway freight system under passenger-freight coordination based on the various cost driver influencing factors mentioned above; Step S3: Based on the life-cycle cost driver relationship model and the passenger and freight revenue of the metro freight system under passenger-freight coordination, predict and evaluate the minimization of the life-cycle cost or the maximization of the benefits of the metro freight system under passenger-freight coordination.

[0006] Furthermore, in step S1, the life-cycle cost model of the subway freight system under passenger-freight coordination is expressed by the following specific formula: 1) The main costs in the project decision-making and design phase include project planning costs, project proposal costs, feasibility study costs, and survey and design fees. The cost calculation model for this phase is as follows: ; in, This refers to the project decision-making and design phase costs discounted to present value. It is the cost of a single item in the annual decision-making design. The number of projects for which the annual decision-making design cost is calculated. It is the timeframe for decision-making and design. It is the discount rate; 2) During the construction phase, costs are related to network planning and the choice of operation mode. Construction costs include demolition costs in the construction area, building and installation costs, equipment purchase costs, and deferred costs. The choice of the M-ULS operation mode directly affects whether the system is based on the reconstruction of the existing subway infrastructure or the construction of new tunnels and stations. The cost calculation model for this phase is expressed as follows: ; ; in, Construction phase costs discounted to present value; This is the annual construction cost. These are various annual construction costs. This refers to the number of projects in the annual construction phase cost; This refers to the construction period of M-ULS; 3) During the operation and maintenance phase, costs include system operation costs, equipment maintenance costs, equipment replacement costs, and passenger / freight coordination costs. The cost calculation model formula is expressed as follows: ; ; in, It is the present value of the system operation and maintenance phase costs. It refers to the number of years of operation and maintenance. This refers to the annual operating and maintenance costs; These are the annual costs for M-ULS operations, equipment maintenance, and passenger / freight coordination. These are the number of operating, equipment maintenance, and collaborative cost items, respectively. This is the equipment replacement cost for the kth item in year t. Let k be the update cycle of device k. Since the update cycles of different devices are different, we take the update coefficient. ,when When it is an integer, ,otherwise ; Frequency of equipment updates; 4) During the end-of-life recycling phase, when the project reaches its designed service life, all key facilities and equipment in the project will sequentially reach the upper limit of their service life and must be depreciated or scrapped. It is necessary to classify these components when calculating the end-of-life recycling cost. The formula is as follows: ; in, It is the cost of the scrapping and recycling stage discounted to present value; It refers to the number of M-ULS facilities and equipment; Facilities and equipment The cost of updating; Facilities and equipment The life cycle.

[0007] Furthermore, in step S2, the life-cycle cost driver relationship model of the subway freight system under passenger-freight coordination, based on the various cost driver influencing factors, is expressed by the following specific formula: 1) During the decision-making and design phase, the costs incurred for the design and planning of each sub-project of the system are calculated based on the project construction cost using a certain proportional coefficient. The formula is as follows: ; in, It is the proportion of decision-making and design costs to the total construction cost; 2) During the construction phase, the cost consists of four components: station construction cost, track construction cost, equipment purchase cost, and locomotive purchase cost. The formula is as follows: ; ; in, These represent the number of stations, lines, system equipment, and locomotives constructed and purchased in year t, respectively. These are the site level, the line laying method, and the equipment type; They are respectively Construction unit cost and installation method of graded sites The unit construction cost of the line, the unit purchase cost of type k equipment, and the unit purchase cost of locomotives; 3) During the operation and maintenance phase, costs consist of operating costs (train transportation costs, warehousing costs, distribution processing costs, and collaborative operation costs), equipment and locomotive replacement and maintenance costs, expressed by the following formula: ; ; in, The quantity of goods transported by M-ULS in the t-th batch of shipments. It is a collection of goods batches that satisfy... , This represents the total freight demand of the system in the [number]th year; The transportation distance for batch i of goods; This refers to the storage time of batch i of goods. These are the system's unit transportation cost, unit warehousing cost, unit distribution processing cost, and passenger-freight coordination cost. This is a category of passenger-freight coordination costs; and These are the update judgment coefficients for system equipment and locomotives, respectively. It is a collection of system equipment types. and These are the maintenance costs of equipment and locomotives, respectively; During the end-of-life recycling phase, the depreciation of system facilities and equipment, including electromechanical equipment, locomotives, lines, and station infrastructure, is calculated based on their original purchase or construction costs. The formula is as follows: ; in, These refer to the design service life of equipment, locomotives, lines, and station infrastructure. For the entire lifecycle of the system, from decision-making to disposal, .

[0008] Furthermore, in step S3, influenced by freight demand, freight unit price, and transportation distance, the passenger and freight revenue of the subway freight system under passenger-freight coordination is expressed by the following formula: ; in, The freight rate for M-ULS is expressed in yuan per ton-kilometer.

[0009] Furthermore, in step S3, the prediction and optimization of minimizing the life-cycle cost or maximizing the benefits of the metro freight system under passenger-freight coordination is expressed by the following formula: .

[0010] Furthermore, during the operation and maintenance phase, additional cost items arising from reduced passenger capacity, safety maintenance costs, passenger delay costs, and integrated management costs are calculated separately for both trailer-mounted and passenger-cargo separated operation modes; specifically including: The decrease in passenger capacity is mainly due to the trailer-type metro freight operation mode, where freight cars occupy passenger transport capacity, thus reducing the revenue of the metro passenger transport system. This can be expressed by the formula: ; in, It is the average fare for subway passenger transport; This is the average passenger capacity of a single passenger train carriage; It refers to the number of freight trains that replace passenger trains in the trailer-type metro-freight mode; The formula for safety maintenance cost is expressed as: ; in, It refers to safety assurance costs, including the costs of safety assurance equipment and measures incurred to ensure the safe operation of trains and the safety of passengers. Loss-related safety costs represent compensatory expenditure costs incurred after a safety incident. Because passenger train departure delays caused by freight trains occupying track capacity under the passenger-freight separation mode, and passenger train departure interval delays caused by freight trains overtaking, are related to the specific operation mode and departure interval of freight trains, the passenger delay cost formula is expressed as: ; in, This refers to the increased waiting time for passengers at the station. This refers to the increased travel time for passengers. It is the value per unit of time, which can be considered as the local average daily income per person; The increased management costs resulting from the centralized control platform's unified allocation and management of passenger and freight transport systems can be categorized into control system upgrade costs and management system upgrade costs, expressed by the following formula: ; in, The cost of upgrading an integrated information management and control system. This refers to the cost of upgrading the M-ULS management system.

[0011] On the other hand, the present invention provides a life-cycle cost assessment system for a subway freight system under passenger-freight coordination, comprising the following modules: The cost model building module is used to build a full life cycle cost model for a subway freight system under passenger-freight coordination, which includes four stages: decision-making and design, construction, operation and maintenance, and decommissioning and recycling. The cost driver model building module is used to identify the key cost drivers affecting the cost of the metro freight system at each stage under the life cycle cost model, including network scale, network layout, construction technology, process operation, and stakeholder collaboration. And to construct a full life-cycle cost driver relationship model for the subway freight system under passenger-freight coordination based on the various cost driver influencing factors mentioned above; The evaluation and prediction module is used to predict and evaluate the minimization of the life cycle cost or the maximization of the benefits of the metro freight system under passenger-freight coordination, based on the life cycle cost driver relationship model and passenger-freight revenue of the metro freight system under passenger-freight coordination.

[0012] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: The method and system for assessing the full life cycle cost of a subway freight system under passenger-freight coordination provided by the present invention, by optimizing cost drivers, helps to accurately and reliably assess the reasonable control of the full life cycle cost of the subway freight system under passenger-freight coordination and maximize the benefits. It can effectively identify and quantify the cost composition of the subway freight system under passenger-freight coordination, and provide a scientific basis for the planning, design, construction and operation of the project. Attached Figure Description

[0013] Figure 1 A flowchart illustrating a method for assessing the full life-cycle cost of a subway freight system under passenger-freight coordination, provided as an embodiment of the present invention.

[0014] Figure 2 This is a diagram illustrating the relationship between cost drivers and cost management objectives for the entire life cycle cost of a subway freight system under passenger-freight coordination, provided as an embodiment of the present invention.

[0015] Figure 3 This diagram illustrates the impact of the depreciation period on net income for the total life-cycle cost of a subway freight system under passenger-freight coordination, as provided in an embodiment of the present invention.

[0016] Figure 4 This invention provides an embodiment of the impact of the number of equipment and facilities on cost management objectives for the entire life cycle cost of a subway freight system under passenger-freight coordination. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0018] like Figure 1As shown in the figure, this embodiment of the invention provides a method for evaluating the full life cycle cost of a subway freight system under passenger-freight coordination, including the following steps: Step S1: Construct a full life cycle cost model for a subway freight system under passenger-freight coordination, including four stages: decision-making and design, construction, operation and maintenance, and decommissioning and recycling. Step S2: Identify the key cost drivers affecting the cost of each stage of the metro freight system under the life-cycle cost model, including network scale, network layout, construction technology, process operation, and stakeholder collaboration. And to construct a full life-cycle cost driver relationship model for the subway freight system under passenger-freight coordination based on the various cost driver influencing factors mentioned above; Step S3: Based on the life-cycle cost driver relationship model and the passenger and freight revenue of the metro freight system under passenger-freight coordination, predict and evaluate the minimization of the life-cycle cost or the maximization of the benefits of the metro freight system under passenger-freight coordination.

[0019] In this embodiment, in step S1, the life-cycle cost model of the subway freight system under passenger-freight coordination is expressed by the following specific formula: 1) The main costs in the project decision-making and design phase include project planning costs, project proposal costs, feasibility study costs, and survey and design fees. The cost calculation model for this phase is as follows: ; in, This refers to the project decision-making and design phase costs discounted to present value. It is the cost of a single item in the annual decision-making design. The number of projects for which the annual decision-making design cost is calculated. It is the timeframe for decision-making and design. It is the discount rate; 2) During the construction phase, costs are related to network planning and the choice of operation mode. Construction costs include demolition costs in the construction area, building and installation costs, equipment purchase costs, and deferred costs. The choice of the M-ULS operation mode directly affects whether the system is based on the reconstruction of the existing subway infrastructure or the construction of new tunnels and stations. The cost calculation model for this phase is expressed as follows: ; ; in, Construction phase costs discounted to present value; This is the annual construction cost. These are various annual construction costs. This refers to the number of projects in the annual construction phase cost; This refers to the construction period of M-ULS; 3) During the operation and maintenance phase, costs include system operation costs, equipment maintenance costs, equipment replacement costs, and passenger / freight coordination costs. The cost calculation model formula is expressed as follows: ; ; in, It is the present value of the system operation and maintenance phase costs. It refers to the number of years of operation and maintenance. This refers to the annual operating and maintenance costs; These are the annual costs for M-ULS operations, equipment maintenance, and passenger / freight coordination. These are the number of operating, equipment maintenance, and collaborative cost items, respectively. This is the equipment replacement cost for the kth item in year t. Let k be the update cycle of device k. Since the update cycles of different devices are different, we take the update coefficient. ,when When it is an integer, ,otherwise ; Frequency of equipment updates; 4) During the end-of-life recycling phase, when the project reaches its designed service life, all key facilities and equipment in the project will sequentially reach the upper limit of their service life and must be depreciated or scrapped. It is necessary to classify these components when calculating the end-of-life recycling cost. The formula is as follows: ; in, It is the cost of the scrapping and recycling stage discounted to present value; It refers to the number of M-ULS facilities and equipment; Facilities and equipment The cost of updating; Facilities and equipment The life cycle.

[0020] In this embodiment, based on the analysis of M-ULS attributes, demand, cost and benefit characteristics, the system's cost and revenue, as important objectives of cost management, are directly affected by cost drivers, which in turn affect the development of the system network and the decision-making on the operation and management mode, as detailed in Table 1.

[0021] Table 1. Cost Drivers of M-ULS

[0022] Cost drivers include network size, network layout, construction technology, process operation, and stakeholder collaboration. Figure 2Specifically, network size, network layout, and collaboration among participants have a direct impact on system revenue; construction costs are affected by network size, network layout, construction technology, and operational processes; operation and maintenance costs are affected by network layout, construction technology, operational processes, and collaboration among participants; and end-of-life recycling costs are affected by network size, network layout, and construction technology.

[0023] The expansion of the M-ULS network and its optimized layout will increase freight demand, resulting in higher economic revenue but also increased system costs. Increased freight demand may further drive the development of the network's scale and layout. M-ULS net revenue is determined by both system revenue and costs, and net income also influences upgrades in construction technology, optimization of operational processes, and adjustments to collaborative models among stakeholders.

[0024] The relationship between the cost drivers and cost management objectives of M-ULS needs to be quantitatively analyzed. Each of the five cost drivers contains multiple influencing factors. Based on the M-ULS life-cycle cost calculation model and cost decomposition structure, and combined with experience in subway system construction, a quantitative relationship between cost drivers and cost management objectives is constructed, and a dynamic impact analysis of M-ULS cost drivers on cost management objectives is conducted. Because numerous factors influence M-ULS costs and revenues, and some are difficult to quantify, not all can be included in the model. Therefore, based on the M-ULS life-cycle cost calculation model, the influencing factors of the five cost drivers are reviewed and screened to determine the boundaries of the relationship between M-ULS cost drivers and cost management objectives, as shown in Table 1.

[0025] In step S2, the life-cycle cost driver relationship model of the subway freight system under passenger-freight coordination, based on the various cost driver influencing factors, is expressed by the following specific formula: 1) During the decision-making and design phase, the costs incurred for the design and planning of each sub-project of the system are calculated based on the project construction cost using a certain proportional coefficient. The formula is as follows: ; in, It is the proportion of decision-making and design costs to the total construction cost; 2) During the construction phase, the cost consists of four components: station construction cost, track construction cost, equipment purchase cost, and locomotive purchase cost. The formula is as follows: ; ; in, These represent the number of stations, lines, system equipment, and locomotives constructed and purchased in year t, respectively. These are the site level, the line laying method, and the equipment type; They are respectively Construction unit cost and installation method of graded sites The unit construction cost of the line, the unit purchase cost of type k equipment, and the unit purchase cost of locomotives; 3) During the operation and maintenance phase, costs consist of operating costs (train transportation costs, warehousing costs, distribution processing costs, and collaborative operation costs), equipment and locomotive replacement and maintenance costs, expressed by the following formula: ; ; in, The quantity of goods transported by M-ULS in the t-th batch of shipments. It is a collection of goods batches that satisfy... , This represents the total freight demand of the system in the [number]th year; The transportation distance for batch i of goods; This refers to the storage time of batch i of goods. These are the system's unit transportation cost, unit warehousing cost, unit distribution processing cost, and passenger-freight coordination cost. This is a category of passenger-freight coordination costs; and These are the update judgment coefficients for system equipment and locomotives, respectively. It is a collection of system equipment types. and These are the maintenance costs of equipment and locomotives, respectively; 4) During the scrapping and recycling phase, the depreciation of system facilities and equipment, including electromechanical equipment, locomotives, lines, and station infrastructure, is calculated based on their original purchase or construction costs. The formula is as follows: ; in, These refer to the design service life of equipment, locomotives, lines, and station infrastructure. For the entire lifecycle of the system, from decision-making to disposal, .

[0026] In step S3, influenced by freight demand, freight unit price, and transportation distance, the passenger and freight revenue of the subway freight system under passenger-freight coordination is expressed by the following formula: ; in, The freight rate for M-ULS is expressed in yuan per ton-kilometer.

[0027] In step S3, the prediction and optimization of minimizing the life-cycle cost or maximizing the benefits of the metro freight system under passenger-freight coordination is expressed by the following formula: .

[0028] In this embodiment, during the operation and maintenance phase, additional cost items arising from reduced passenger capacity, safety maintenance costs, passenger delay costs, and integrated management costs are calculated for both trailer-mounted and passenger-cargo separated operation modes; specifically including: The decrease in passenger capacity is mainly due to the trailer-type metro freight operation mode, where freight cars occupy passenger transport capacity, thus reducing the revenue of the metro passenger transport system. This can be expressed by the formula: In this embodiment, during the operation and maintenance phase, additional cost items arising from reduced passenger capacity, safety maintenance costs, passenger delay costs, and integrated management costs are calculated for both trailer-mounted and passenger-cargo separated operation modes; specifically including: The decrease in passenger capacity is mainly due to the trailer-type metro freight operation mode, where freight cars occupy passenger transport capacity, thus reducing the revenue of the metro passenger transport system. This can be expressed by the formula: ; in, It is the average fare for subway passenger transport; This is the average passenger capacity of a single passenger train carriage; It refers to the number of freight trains that replace passenger trains in the trailer-type metro-freight mode; The formula for safety maintenance cost is expressed as: ; in, It refers to safety assurance costs, including the costs of safety assurance equipment and measures incurred to ensure the safe operation of trains and the safety of passengers. Loss-related safety costs represent compensatory expenditure costs incurred after a safety incident. Because passenger train departure delays caused by freight trains occupying track capacity under the passenger-freight separation mode, and passenger train departure interval delays caused by freight trains overtaking, are related to the specific operation mode and departure interval of freight trains, the passenger delay cost formula is expressed as: ; in, This refers to the increased waiting time for passengers at the station. This refers to the increased travel time for passengers. It is the value per unit of time, which can be considered as the local average daily income per person; The increased management costs resulting from the centralized control platform's unified allocation and management of passenger and freight transport systems can be categorized into control system upgrade costs and management system upgrade costs, expressed by the following formula: ; in, The cost of upgrading an integrated information management and control system. This refers to the cost of upgrading the M-ULS management system.

[0029] In this embodiment, it is assumed that different types of facilities and equipment are positively correlated with freight demand. A small-scale experimental case is used to discuss the impact of key cost drivers on the system cost management objectives. Assume that the city's daily freight demand is 60, the freight handling capacity of freight stations is 10, the cargo handling capacity of logistics equipment is 0.8, the average freight transport distance is 20, the depreciation period is 50 years, the economic growth rate is 6%, the discount rate is 8%, and other cost parameters are set as shown in Table 2. The analysis is based on a single-line subway freight network.

[0030] Table 2 System Cost Parameter Settings for Small-Scale Cases

[0031] In this embodiment, the impact of depreciation period on cost management objectives is considered. Calculations show that, taking a system with 2 stations as an example, the annual operating cost is 1.087, while the construction cost is 12.303. The construction cost is high, but considering the depreciation period, the proportion of operating cost in the total system lifecycle cost increases when calculating the present value of operating costs. The net system revenue for different depreciation periods under different system network sizes (number of freight stations) is calculated, and the results are shown in Table 3.

[0032] Table 3. Impact of Depreciation Periods on System Net Income under Different Network Sizes

[0033] The impact of depreciation period on system net income shows a similar trend across different network sizes. Initially, net income increases with the increase in depreciation period, reaching its peak between 20 and 30 years. Then, with further increases in depreciation period, net income gradually decreases and may even turn negative. Figure 3 As can be seen, net revenue increases rapidly from 2 to 6 stations, reaching its maximum at 6 stations. This is because, according to the case study, the system perfectly meets the city's freight demand with 6 stations. This means that when freight demand is sufficiently high, a larger network scale results in greater net revenue. However, when freight demand reaches saturation, further expansion of the network scale will increase costs, leading to a decrease in net revenue. When the number of stations is 6 or less, the depreciation period for net revenue to drop to zero is the longest, exceeding 90 years, meaning the system's profitable period is longer. Conversely, when network supply exceeds market demand, a larger network scale results in a shorter critical depreciation period. This implies that the economics of M-ULS depend on the balance between urban freight demand and the system network scale. Therefore, M-ULS construction decisions should be based on a long-term planning perspective, expanding the system network scale in stages according to the freight market potential.

[0034] Considering the impact of the number of facilities and equipment on cost management objectives, calculations show that, after 50 years of depreciation, operating costs are the highest stage cost in the system's total life cycle cost. Since there is a linear correlation between the number of network facilities (sites, tunnels), the number of sites is used as a representative of the number of equipment to represent the network scale. Figure 4 It is evident that when urban freight demand is high but network resources are insufficient, expanding the network scale (increasing the number of stations / devices) can improve net revenue. In the example, when the number of stations is 6 and the number of devices is 75, the network just meets all freight demand, maximizing net revenue. At this point, further expansion will rapidly reduce the system's net revenue.

[0035] When urban freight demand is high, insufficient network infrastructure or equipment resources will become a bottleneck in achieving system cost management goals, thus limiting the increase in system revenue. Increasing the allocation of other individual resources will not raise the upper limit of system capacity and thus increase net revenue; instead, it will increase system costs and even cause serious operational losses. Therefore, the network resource allocation of M-ULS should seek a balance in quantity and layout while meeting freight demand, in order to achieve a reasonable assessment and optimization of system cost management goals.

[0036] On the other hand, embodiments of the present invention improve a life-cycle cost assessment system for a subway freight system under passenger-freight coordination, comprising the following modules: The cost model building module is used to build a full life cycle cost model for a subway freight system under passenger-freight coordination, which includes four stages: decision-making and design, construction, operation and maintenance, and decommissioning and recycling. The cost driver model building module is used to identify the key cost drivers affecting the cost of the metro freight system at each stage under the life cycle cost model, including network scale, network layout, construction technology, process operation, and stakeholder collaboration. And to construct a full life-cycle cost driver relationship model for the subway freight system under passenger-freight coordination based on the various cost driver influencing factors mentioned above; The evaluation and prediction module is used to predict and evaluate the minimization of the life cycle cost or the maximization of the benefits of the metro freight system under passenger-freight coordination, based on the life cycle cost driver relationship model and passenger-freight revenue of the metro freight system under passenger-freight coordination.

[0037] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for evaluating the full life-cycle cost of a subway freight system under passenger-freight coordination, characterized in that, Includes the following steps: Step S1: Construct a full life cycle cost model for a subway freight system under passenger-freight coordination, including four stages: decision-making and design, construction, operation and maintenance, and decommissioning and recycling. Step S2: Identify the key cost drivers affecting the cost of each stage of the metro freight system under the life-cycle cost model, including network scale, network layout, construction technology, process operation, and stakeholder collaboration. And to construct a full life-cycle cost driver relationship model for the subway freight system under passenger-freight coordination based on the various cost driver influencing factors mentioned above; Step S3: Based on the life-cycle cost driver relationship model and the passenger and freight revenue of the metro freight system under passenger-freight coordination, predict and evaluate the minimization of the life-cycle cost or the maximization of the benefits of the metro freight system under passenger-freight coordination.

2. The method for evaluating the full life-cycle cost of a subway freight system under passenger-freight coordination as described in claim 1, characterized in that, In step S1, the life-cycle cost model of the subway freight system under passenger-freight coordination is expressed by the following specific formula: 1) The main costs in the project decision-making and design phase include project planning costs, project proposal costs, feasibility study costs, and survey and design fees. The cost calculation model for this phase is as follows: ； in, This refers to the project decision-making and design phase costs discounted to present value. It is the cost of a single item in the annual decision-making design. The number of projects for which the annual decision-making design cost is calculated. It is the timeframe for decision-making and design. It is the discount rate; 2) During the construction phase, costs are related to network planning and the choice of operation mode. Construction costs include demolition costs in the construction area, building and installation costs, equipment purchase costs, and deferred costs. The choice of the M-ULS operation mode directly affects whether the system is based on the reconstruction of the existing subway infrastructure or the construction of new tunnels and stations. The cost calculation model for this phase is expressed as follows: ； ； in, Construction phase costs discounted to present value; This is the annual construction cost. These are various annual construction costs. This refers to the number of projects in the annual construction phase cost; This refers to the construction period of M-ULS; 3) During the operation and maintenance phase, costs include system operation costs, equipment maintenance costs, equipment replacement costs, and passenger / freight coordination costs. The cost calculation model formula is expressed as follows: ； ； in, It is the present value of the system operation and maintenance phase costs. It refers to the number of years of operation and maintenance. This refers to the annual operating and maintenance costs; These are the annual costs for M-ULS operations, equipment maintenance, and passenger / freight coordination. These are the number of operating, equipment maintenance, and collaborative cost items, respectively. This is the equipment replacement cost for the kth item in year t. Let k be the update cycle of device k. Since the update cycles of different devices are different, we take the update coefficient. ,when When it is an integer, ,otherwise ; Frequency of equipment updates; 4) During the end-of-life recycling phase, when the project reaches its designed service life, all key facilities and equipment in the project will sequentially reach the upper limit of their service life and must be depreciated or scrapped. It is necessary to classify these components when calculating the end-of-life recycling cost. The formula is as follows: ； in, It is the cost of the scrapping and recycling stage discounted to present value; It refers to the number of M-ULS facilities and equipment; Facilities and equipment The cost of updating; Facilities and equipment The life cycle.

3. The method for evaluating the full life-cycle cost of a subway freight system under passenger-freight coordination as described in claim 1, characterized in that, In step S2, the life-cycle cost driver relationship model of the subway freight system under passenger-freight coordination, based on the various cost driver influencing factors, is expressed by the following specific formula: 1) During the decision-making and design phase, the costs incurred for the design and planning of each sub-project of the system are calculated based on the project construction cost using a certain proportional coefficient. The formula is as follows: ； in, It is the proportion of decision-making and design costs to the total construction cost; 2) During the construction phase, the cost consists of four components: station construction cost, track construction cost, equipment purchase cost, and locomotive purchase cost. The formula is as follows: ； ； in, These represent the number of stations, lines, system equipment, and locomotives constructed and purchased in year t, respectively. These are the site level, the line laying method, and the equipment type; They are respectively Construction unit cost and installation method of graded sites The unit construction cost of the line, the unit purchase cost of type k equipment, and the unit purchase cost of locomotives; 3) During the operation and maintenance phase, costs consist of operating costs (train transportation costs, warehousing costs, distribution processing costs, and collaborative operation costs), equipment and locomotive replacement and maintenance costs, expressed by the following formula: ； ； in, The quantity of goods transported by M-ULS in the t-th batch of shipments. It is a collection of goods batches that satisfy... , This represents the total freight demand of the system in the [number]th year; The transportation distance for batch i of goods; This refers to the storage time of batch i of goods. These are the system's unit transportation cost, unit warehousing cost, unit distribution processing cost, and passenger-freight coordination cost. This is a category of passenger-freight coordination costs; and These are the update judgment coefficients for system equipment and locomotives, respectively. It is a collection of system equipment types. and These are the maintenance costs of equipment and locomotives, respectively; During the end-of-life recycling phase, the depreciation of system facilities and equipment, including electromechanical equipment, locomotives, lines, and station infrastructure, is calculated based on their original purchase or construction costs. The formula is as follows: ； in, These refer to the design service life of equipment, locomotives, lines, and station infrastructure. For the entire lifecycle of the system, from decision-making to disposal, .

4. The method for evaluating the full life-cycle cost of a subway freight system under passenger-freight coordination as described in claim 3, is characterized in that, In step S3, influenced by freight demand, freight unit price, and transportation distance, the passenger and freight revenue of the subway freight system under passenger-freight coordination is expressed by the following formula: ； in, The freight rate for M-ULS is expressed in yuan per ton-kilometer.

5. The method for evaluating the full life-cycle cost of a subway freight system under passenger-freight coordination as described in claim 4, characterized in that, In step S3, the prediction and optimization of minimizing the life-cycle cost or maximizing the benefits of the metro freight system under passenger-freight coordination is expressed by the following formula: .

6. The method for evaluating the full life-cycle cost of a subway freight system under passenger-freight coordination as described in claim 5, is characterized in that, During the operation and maintenance phase, additional cost items arising from reduced passenger capacity, safety maintenance costs, passenger delay costs, and integrated management costs are calculated separately for both trailer-mounted and passenger-cargo separated operation modes; specifically including: The decrease in passenger capacity is mainly due to the trailer-type metro freight operation mode, where freight cars occupy passenger transport capacity, thus reducing the revenue of the metro passenger transport system. This can be expressed by the formula: ； in, It is the average fare for subway passenger transport; This is the average passenger capacity of a single passenger train carriage; It refers to the number of freight trains that replace passenger trains in the trailer-type metro-freight mode; The formula for safety maintenance cost is expressed as: ； in, It refers to safety assurance costs, including the costs of safety assurance equipment and measures incurred to ensure the safe operation of trains and the safety of passengers. Loss-related safety costs represent compensatory expenditure costs incurred after a safety incident. Because passenger train departure delays caused by freight trains occupying track capacity under the passenger-freight separation mode, and passenger train departure interval delays caused by freight trains overtaking, are related to the specific operation mode and departure interval of freight trains, the passenger delay cost formula is expressed as: ； in, This refers to the increased waiting time for passengers at the station. This refers to the increased travel time for passengers. It is the value per unit of time, which can be considered as the local average daily income per person; The increased management costs resulting from the centralized control platform's unified allocation and management of passenger and freight transport systems can be categorized into control system upgrade costs and management system upgrade costs, expressed by the following formula: ； in, The cost of upgrading an integrated information management and control system. This refers to the cost of upgrading the M-ULS management system.

7. A life-cycle cost assessment system for a subway freight system under passenger-freight coordination, characterized in that, Includes the following modules: The cost model building module is used to build a full life cycle cost model for a subway freight system under passenger-freight coordination, which includes four stages: decision-making and design, construction, operation and maintenance, and decommissioning and recycling. The cost driver model building module is used to identify the key cost drivers affecting the cost of the metro freight system at each stage under the life cycle cost model, including network scale, network layout, construction technology, process operation, and stakeholder collaboration. And to construct a full life-cycle cost driver relationship model for the subway freight system under passenger-freight coordination based on the various cost driver influencing factors mentioned above; The evaluation and prediction module is used to predict and evaluate the minimization of the life cycle cost or the maximization of the benefits of the metro freight system under passenger-freight coordination, based on the life cycle cost driver relationship model and passenger-freight revenue of the metro freight system under passenger-freight coordination.

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