Method and device for recognizing traffic operation state of road intersection

Abstract

The present application belongs to the technical field of urban traffic management, and discloses a road all-intersections traffic operation state recognition method and device. The method comprises the following steps: calculating the road section traffic operation index of each all-intersection according to the vehicle passing data collected by each checkpoint device arranged on the road network of the target area to recognize the road section traffic operation state, and calculating the intersection intensity index; obtaining the all-intersection comprehensive traffic operation index through the weighted fusion of the road section traffic operation index and the intersection intensity index; presetting the traffic operation state grade division standard, mapping the obtained all-intersection comprehensive traffic operation index to the corresponding traffic operation state grade, and outputting the recognition result. The present application is suitable for the recognition of urban road traffic operation state, provides efficient and reliable decision support for the fine traffic management, and saves the manpower and time cost of the traffic management department.

Description

Technical Field

[0001] This invention belongs to the field of urban traffic management technology and relates to a method and device for identifying traffic operation status at road intersections. Background Technology

[0002] With the continuous acceleration of urbanization and the rapid growth of motor vehicle ownership in my country, urban road traffic systems have become core infrastructure supporting urban operations and ensuring residents' travel. Their operational status directly impacts urban efficiency, residents' travel experience, and the regional ecological environment. Statistics show that my country's motor vehicle ownership has exceeded 430 million, with more than 50 cities nationwide having over one million vehicles. Traffic congestion during morning and evening rush hours is particularly prominent. Traffic congestion not only affects residents' travel efficiency but has also become a typical urban problem hindering high-quality urban development. Therefore, accurate and real-time identification of road traffic operation status has become a crucial prerequisite for implementing refined traffic management, optimizing signal timing, easing congestion, and improving the public's travel experience.

[0003] Currently, urban traffic management departments generally rely on road condition data or congestion indices provided by third-party internet companies to identify road traffic conditions. While this type of data has advantages such as broad macro-level coverage and high visualization, there is a gap between its data source, calculation model, and the traffic management department's own perception system. This makes it difficult for traffic management departments to independently and accurately grasp the actual operating characteristics of roads within their jurisdiction using their existing traffic monitoring facilities.

[0004] Meanwhile, in terms of urban road infrastructure, traffic management departments have widely deployed checkpoint equipment at urban intersections and surrounding road sections. These devices are typically located approximately 50 meters upstream of the intersection and are capable of collecting data such as vehicle passage time, license plate numbers, and lane information, effectively reflecting the traffic flow status of the intersection and its upstream road sections. However, existing technologies, when evaluating traffic operation status, often treat intersections and road sections as independent units, lacking a comprehensive consideration of their inherent correlation in the traffic flow process. This makes it difficult to achieve a holistic and unified identification of the operational status of the broader intersection area comprised of the intersection and its upstream road sections.

[0005] In summary, how to fully utilize the traffic data collected by existing checkpoint equipment to construct an identification method that can comprehensively reflect the overall operational status of the intersection area and its upstream road segments, and overcome the limitations of traditional evaluation methods that separate road segments from intersections, has become an urgent technical problem to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to provide a method for identifying the traffic operation status of road intersections, which aims to make full use of the data from existing checkpoint equipment in the city to achieve accurate and comprehensive identification of the traffic operation status of the intersection area consisting of road intersections and their upstream road sections. Another objective of this invention is to provide a traffic operation status identification device for road intersections.

[0007] To achieve the above objectives, the technical solution adopted by this invention is as follows: A method for identifying traffic operation status at road intersections includes the following steps: S1. Obtain vehicle traffic data collected by checkpoint equipment deployed on the road network in the target area, preprocess the vehicle traffic data to obtain the actual traffic flow in each direction of the road intersection and the total traffic flow of the intersection, and calculate the vehicle passage time of each road segment. S2. Based on the location information of each checkpoint device and its upstream and downstream relationships, the urban roads are divided into multiple general intersections. Each general intersection includes a road intersection and the upstream road segment adjacent to that road intersection. S3. Based on the data obtained in step S1, calculate the upstream road segment in the general intersection. The road segment traffic operation index, and the road segments included in the general intersection and the upstream road segments Corresponding import direction The intersection strength index; S4. Based on the road segment traffic operation index and intersection intensity index obtained in step S3, a weighted fusion is performed to obtain the general intersection comprehensive traffic operation index. S5. Preset traffic operation status level classification standards, map the obtained comprehensive traffic operation index of the general intersection to the corresponding traffic operation status level, and output the recognition results.

[0008] As a limitation, in step S3, the upstream road segment in the general intersection is calculated. The process of calculating the traffic operation index for a road segment is as follows: S301. Divide the day from 6:00 to 24:00 into preset time intervals and calculate the upstream road segment of the intersection within the preset number of days. Calculate the historical average vehicle speed within each time interval; sort the obtained historical average vehicle speeds from largest to smallest; based on the sorting result, take the top N% and average them again; the result is used as the upstream segment in the general intersection. The free flow velocity; S302. Based on the vehicle passage time of each road segment obtained in step S1, calculate the upstream road segment in the general intersection. The actual average operating speed of vehicles during the current time period; S303, based on the upstream section of the intersection Calculate the free-flow velocity and the actual average vehicle speed to determine the upstream segment of the intersection. The road speed ratio during the current time period; S304. Establish a linear functional relationship between the road speed ratio and the road segment traffic index, and calculate the upstream road segment in the general intersection. Traffic operation index of the road section.

[0009] As a further limitation, in step S301, the preset time interval is no more than 15 minutes, the preset number of days is no less than 20 days, and N=1 / 9; In step S302, the upstream road segment in the general intersection The formula for calculating the actual average speed of vehicles during the current time period is: in, Upstream section of the intersection In the current period The actual average operating speed of vehicles within the vehicle; In the current period Inner Vehicles on the upstream section of the intersection The distance traveled; In the current period Inner Vehicles on the upstream section of the intersection The itinerary time; For the current time period Upstream section of the inner intersection Number of times the car was driven; In step S303, the upstream road segment in the general intersection The formula for calculating the road speed ratio in the current time period is: in, Upstream section of the intersection In the current period The road operating speed ratio; Upstream section of the intersection The free flow velocity; In step S304, the linear functional relationship between the road operating speed ratio and the road segment traffic operation index is as follows: in, Upstream section of the intersection Traffic operation index of the road section.

[0010] As a further limitation, in step S3, the upstream road segment of the road intersection included in the general intersection is calculated. Corresponding import direction The process of calculating the intersection strength index is as follows: S311. Obtain the signal timing parameters of the road intersections included in the general intersection, including signal cycle and green light time, calculate the capacity of a single lane of the road intersection, and determine the capacity of the road intersection in the approach direction based on the lane configuration of the road intersection. The road capacity; S312. The road intersection obtained in step S1 is in the approach direction. Calculate the actual traffic flow at the road intersection in the approach direction. The ratio of actual traffic flow to road capacity is used to obtain the intersection's onward direction. The intersection strength index.

[0011] As a further limitation, in step S311, the formula for calculating the traffic capacity of a single lane at a road intersection is: in, This refers to the actual traffic capacity of a single lane at a road intersection within a general intersection. The signal cycle for road intersections within a general intersection; The green light time within the signal cycle; Road intersection on the inbound direction The formula for calculating road capacity is: in, For road intersections in the general intersection category, the approach direction is... The road capacity; For road intersections in the general intersection category, the approach direction is... The number of lanes; In step S312, the road intersection is in the direction of the entrance. The formula for calculating the intersection strength index is: in, For road intersections in the general intersection category, the approach direction is... The intersection strength index; For road intersections in the general intersection category, the approach direction is... Actual traffic flow.

[0012] As a second limitation, in step S4, the formula for calculating the comprehensive traffic operation index of the general intersection is: in, The comprehensive traffic operation index for intersections; Upstream section of the intersection Traffic operation index of the road section; For road intersections in the general intersection category, the approach direction is... The intersection strength index; and The preset weighting coefficients, This is the normalization factor.

[0013] As a further limitation, the aforementioned The value is 0.4. The value is 0.6, the normalization factor. The value is 0.24.

[0014] As a third limitation, in step S5, the preset traffic operation status level classification standard includes: When the comprehensive traffic operation index of the intersection is less than the first threshold, it is judged to be in a smooth state; When the comprehensive traffic operation index of the intersection is greater than or equal to the first threshold and less than the second threshold, it is determined to be a slow-moving state. When the comprehensive traffic operation index of the intersection is greater than or equal to the second threshold and less than the third threshold, it is judged as a congested state. When the comprehensive traffic operation index of the intersection is greater than or equal to the third threshold, it is judged as a state of severe congestion.

[0015] As a further limitation, the first threshold is 0.6, the second threshold is 0.8, and the third threshold is 1.0.

[0016] The present invention also provides a road intersection traffic operation status identification device for performing the above-described road intersection traffic operation status identification method, comprising: The data acquisition module is used to acquire vehicle traffic data collected by various checkpoint devices deployed on the road network in the target area, preprocess the vehicle traffic data to obtain the actual traffic flow in each direction of the road intersection and the total traffic flow of the intersection, and calculate the vehicle passage time of each road segment. The road segment division module is used to divide urban roads into multiple general intersections based on the location information of each checkpoint device and its upstream and downstream relationships. Each general intersection includes a road intersection and the upstream road segment adjacent to that road intersection. The first index calculation module is used to calculate the upstream road segment in a general intersection. The road segment traffic operation index, and the road segments included in the general intersection and the upstream road segments Corresponding import direction The intersection strength index; The second index calculation module is used to perform weighted fusion based on the obtained road segment traffic operation index and intersection intensity index to obtain the comprehensive traffic operation index of the general intersection. The status determination module is used to preset the traffic operation status level classification standard, map the obtained comprehensive traffic operation index of the general intersection to the corresponding traffic operation status level, and output the recognition result.

[0017] The present invention, by adopting the above-described technical solution, achieves the following technical advancements compared to existing technologies: (1) The present invention constructs a general intersection consisting of a road intersection and the upstream road segment adjacent to the road intersection, which breaks the limitation of evaluating road intersections and road segments separately in the traditional technology. It integrates the road intersection and its upstream road segment, which have strong spatial continuity of traffic flow, into a unified general intersection evaluation object, so that the identification results of traffic operation status can more realistically reflect the overall traffic efficiency of the area. (2) This invention obtains a comprehensive traffic operation index for general intersections by weighted fusion of road segment traffic operation index and intersection intensity index. The road segment traffic operation index represents the road segment operation efficiency, and the intersection intensity index represents the intersection traffic pressure. Through scientific weight allocation, a single quantitative indicator that can comprehensively reflect the comprehensive operation status of general intersections is formed, providing traffic management departments with a more accurate and comprehensive decision-making basis. (3) The present invention is based on the checkpoint data owned by the traffic management department for model construction and status recognition. It does not rely on external data sources, which not only improves the efficiency of data utilization, but also enhances the autonomy, reliability and security of the traffic operation status recognition system, providing strong technical support for the refined management of urban traffic.

[0018] In summary, this invention is applicable to the identification of urban road traffic operation status, providing efficient and reliable decision support for refined traffic management, and saving manpower and time costs for traffic management departments. Attached Figure Description

[0019] Figure 1 The diagram shown is a flowchart of the method in Embodiment 1 of the present invention; Figure 2 The diagram shown is a structural block diagram of Embodiment 2 of the present invention. Detailed Implementation

[0020] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] Example 1: A method for identifying traffic operation status at road intersections like Figure 1 As shown in the figure, this embodiment is a method for identifying the traffic operation status of road intersections, including the following steps: S1. Obtain vehicle traffic data collected by checkpoint equipment deployed on the road network in the target area, preprocess the vehicle traffic data to obtain the actual traffic flow in each direction of the road intersection and the total traffic flow of the intersection, and calculate the vehicle passage time of each road segment.

[0022] The specific process for this step is as follows: S11. Obtain basic information about each checkpoint device deployed on the road network in the target area, such as device number, latitude and longitude coordinates, and road segment; obtain vehicle traffic data collected by each checkpoint device, which includes at least information such as vehicle passage time, license plate number, and lane number.

[0023] S12. Preprocess the acquired vehicle traffic data, including: (1) Data cleaning, removing records that do not conform to logic or have obvious errors, including: removing records with empty passage time or incorrect format; removing records with empty license plate number or that do not conform to national standard format; removing records with unknown or abnormal vehicle type (such as unidentifiable vehicle model code); removing redundant data of the same vehicle recorded repeatedly at the same checkpoint and within the same second, etc.

[0024] (2) Time slice The cleaned data is aggregated according to a preset time granularity. In this embodiment, the entire day is divided into 96 time slices with a 15-minute time interval. For each time slice, the number of vehicles passing through each checkpoint device within that time slice is counted as the traffic flow for that road segment within that time slice; simultaneously, the timestamps of the passing vehicles are extracted as the basis for subsequent travel time calculations.

[0025] (3) Spatial matching and path association: Using a Geographic Information System (GIS), the latitude and longitude coordinates of each checkpoint device are matched to the specific location on the road network, and the relationship between upstream and downstream checkpoints is established. Specifically, this includes: Each checkpoint device is linked to its corresponding road segment, and the direction of its entrance to the road intersection is determined. Based on the road topology, upstream checkpoints located at the same road intersection and in the same direction of entrance are associated with the road intersection. For scenarios that require calculating vehicle passage time on a road segment, the timestamps of the same vehicle passing through the upstream and downstream checkpoints (or vehicle passage time intersections) consecutively in the same direction of entry are paired to calculate the travel time of the vehicle through the road segment.

[0026] (4) Traffic flow statistics at intersections Based on spatial matching and path association results, the traffic flow of each approach direction at each road intersection within a preset time slot is calculated. The specific method is as follows: For a certain direction of an entrance to a road intersection, the total number of vehicle passages recorded by the upstream checkpoint within that time slice is taken as the traffic flow for that direction; the total traffic flow for the road intersection is obtained by summing the traffic flows for each direction of entrance.

[0027] S13. Based on the preprocessed vehicle traffic data, obtain the actual traffic flow in each direction of the road intersection and the total traffic flow of the intersection, and calculate the vehicle passage time for each road segment.

[0028] S2. Based on the location information of each checkpoint device and its upstream and downstream relationships, the urban roads are divided into multiple general intersections. Each general intersection includes a road intersection and the upstream road segment adjacent to that road intersection.

[0029] For example, a typical crossroads can be defined as a general intersection, encompassing the road segments covered by checkpoints in each of the upstream approach directions. This classification ensures spatial integrity and logical traffic flow during assessment.

[0030] S3. Based on the data obtained in step S1, calculate the upstream road segment in the general intersection. The road segment traffic operation index, and the road segments included in the general intersection and the upstream road segments Corresponding import direction The intersection strength index.

[0031] In this step, the road segment traffic operation index is calculated using mathematical analysis statistics and fuzzy comprehensive rating methods to construct the corresponding functional relationship, and finally the road segment traffic operation index is obtained through linear functional relationship.

[0032] Among them, the upstream road segment in the general intersection is calculated. The process of calculating the traffic operation index for a road segment is as follows: S301. Divide the day from 6:00 to 24:00 into preset time intervals and calculate the upstream road segment of the intersection within the preset number of days. Calculate the historical average vehicle speed within each time interval; sort the obtained historical average vehicle speeds from largest to smallest; based on the sorting result, take the top N% and average them again; the result is used as the upstream segment in the general intersection. The free flow velocity.

[0033] In this step, the time from 6:00 to 24:00 is divided into 72 time intervals at 15-minute intervals. If 20 days are selected, there will be 1440 time intervals. The historical average running speed of vehicles in each time interval is calculated.

[0034] S302. Based on the vehicle passage time of each road segment obtained in step S1, calculate the upstream road segment in the general intersection. The actual average speed of vehicles during the current time period: in, Upstream section of the intersection In the current period The actual average operating speed of vehicles within the vehicle; In the current period Inner Vehicles on the upstream section of the intersection The distance traveled; In the current period Inner Vehicles on the upstream section of the intersection The itinerary time; For the current time period Upstream section of the inner intersection Number of times the car was driven.

[0035] S303, based on the upstream section of the intersection Calculate the free-flow velocity and the actual average vehicle speed to determine the upstream segment of the intersection. The road speed ratio during the current time period: in, Upstream section of the intersection In the current period The road operating speed ratio; Upstream section of the intersection The free flow velocity.

[0036] S304. Establish a linear functional relationship between the road speed ratio and the road segment traffic index, and calculate the upstream road segment in the general intersection. Traffic operation index of the road section.

[0037] In this step, taking into account the positive correlation between the congestion level of road segments and the traffic index used by the Internet to characterize traffic congestion, a linear functional relationship between the road speed ratio and the road segment traffic operation index is established, and the road speed ratio is converted into the road segment traffic operation index.

[0038] The linear functional relationship between the road speed ratio and the road segment traffic index is as follows: in, Upstream section of the intersection Traffic operation index of the road section.

[0039] In this step, the intersection intensity index is used to characterize the traffic pressure experienced by a road intersection, i.e., its saturation level. The index is calculated for the road intersections included in this general intersection and their upstream segments. Corresponding import direction The process of calculating the intersection strength index is as follows: S311. Obtain the signal timing parameters of the road intersections included in the general intersection, including signal cycle and green light time, calculate the capacity of a single lane of the road intersection, and determine the capacity of the road intersection in the approach direction based on the lane configuration of the road intersection. The road's traffic capacity.

[0040] The formula for calculating the traffic capacity of a single lane at a road intersection is: in, This refers to the actual traffic capacity of a single lane at a road intersection within a general intersection. The signal cycle for road intersections within a general intersection; The green light time within the signal cycle.

[0041] For a given approach direction at a road intersection, the road capacity is the sum of the capacities of all lanes in that direction. The road capacity at the approach direction of the intersection... The formula for calculating road capacity is: in, For road intersections in the general intersection category, the approach direction is... The road capacity; For road intersections in the general intersection category, the approach direction is... The number of lanes.

[0042] S312. The road intersection obtained in step S1 is in the approach direction. Calculate the actual traffic flow at the road intersection in the approach direction. The ratio of actual traffic flow to road capacity is used to obtain the intersection's onward direction. The intersection strength index.

[0043] Road intersection on the inbound direction The formula for calculating the intersection strength index is: in, For road intersections in the general intersection category, the approach direction is... The intersection strength index; For road intersections in the general intersection category, the approach direction is... Actual traffic flow.

[0044] S4. Based on the road segment traffic operation index and intersection intensity index obtained in step S3, a weighted fusion is performed to obtain the general intersection comprehensive traffic operation index. In this step, the formula for calculating the comprehensive traffic operation index of the general intersection is: in, The comprehensive traffic operation index for intersections; Upstream section of the intersection Traffic operation index of the road section; For road intersections in the general intersection category, the approach direction is... The intersection strength index; and The preset weighting coefficients, This is the normalization factor.

[0045] S5. Preset traffic operation status level classification standards, map the obtained comprehensive traffic operation index of the general intersection to the corresponding traffic operation status level, and output the recognition results.

[0046] In this step, based on actual travel experience, road traffic conditions are categorized into four levels: smooth traffic, slow traffic, congested traffic, and severe congestion. The pre-defined criteria for classifying traffic conditions include: When the comprehensive traffic operation index of the intersection is less than the first threshold, it is judged to be in a smooth state; When the comprehensive traffic operation index of the intersection is greater than or equal to the first threshold and less than the second threshold, it is determined to be a slow-moving state. When the comprehensive traffic operation index of the intersection is greater than or equal to the second threshold and less than the third threshold, it is judged as a congested state. When the comprehensive traffic operation index of the intersection is greater than or equal to the third threshold, it is judged as a state of severe congestion.

[0047] The first threshold is 0.6, the second threshold is 0.8, and the third threshold is 1.0. The traffic operation status classification standards are shown in Table 1. Based on the interval where the calculated comprehensive traffic operation index of the intersection falls, the traffic operation status of the intersection in the corresponding time period can be determined.

[0048] Table 1. Traffic Operation Status Classification Standards

[0049] Example 2: A traffic operation status identification device for road intersections This embodiment is a traffic operation status identification device for road intersections, such as... Figure 2 The diagram shown is a block diagram of a road intersection traffic operation status identification device provided according to the method of Embodiment 1. The device includes: The data acquisition module is used to acquire vehicle traffic data collected by various checkpoint devices deployed on the road network in the target area, preprocess the vehicle traffic data to obtain the actual traffic flow in each direction of the road intersection and the total traffic flow of the intersection, and calculate the vehicle passage time of each road segment. The road segment division module is used to divide urban roads into multiple general intersections based on the location information of each checkpoint device and its upstream and downstream relationships. Each general intersection includes a road intersection and the upstream road segment adjacent to that road intersection. The first index calculation module is used to calculate the upstream road segment in a general intersection. The road segment traffic operation index, and the road segments included in the general intersection and the upstream road segments Corresponding import direction The intersection strength index; The second index calculation module is used to perform weighted fusion based on the obtained road segment traffic operation index and intersection intensity index to obtain the comprehensive traffic operation index of the general intersection. The status determination module is used to preset the traffic operation status level classification standard, map the obtained comprehensive traffic operation index of the general intersection to the corresponding traffic operation status level, and output the recognition result.

[0050] It should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions described in the above embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for identifying a traffic operation state at a road intersection, characterized by, Includes the following steps: S1. Obtain vehicle traffic data collected by checkpoint equipment deployed on the road network in the target area, preprocess the vehicle traffic data to obtain the actual traffic flow in each direction of the road intersection and the total traffic flow of the intersection, and calculate the vehicle passage time of each road segment. S2. Based on the location information of each checkpoint device and its upstream and downstream relationships, the urban roads are divided into multiple general intersections. Each general intersection includes a road intersection and the upstream road segment adjacent to that road intersection. S3、based on the data obtained in step S1, calculating the upstream road segment in the generic intersection traffic operation index, and the intersection strength index of the road intersection corresponding to the upstream road segment in the generic intersection corresponding import direction S4. Based on the road segment traffic operation index and intersection intensity index obtained in step S3, a weighted fusion is performed to obtain the general intersection comprehensive traffic operation index. S5. Preset traffic operation status level classification standards, map the obtained comprehensive traffic operation index of the general intersection to the corresponding traffic operation status level, and output the recognition results.

2. The method for identifying traffic operation status at road intersections according to claim 1, characterized in that, In step S3, the upstream road segment in the general intersection is calculated. The process of calculating the traffic operation index for a road segment is as follows: S301. Divide the day from 6:00 to 24:00 into preset time intervals and calculate the upstream road segment of the intersection within the preset number of days. Calculate the historical average vehicle speed within each time interval; sort the obtained historical average vehicle speeds from largest to smallest; based on the sorting result, take the top N% and average them again; the result is used as the upstream segment in the general intersection. The free flow velocity; S302. Based on the vehicle passage time of each road segment obtained in step S1, calculate the upstream road segment in the general intersection. The actual average operating speed of vehicles during the current time period; S303, based on the upstream section of the intersection Calculate the free-flow velocity and the actual average vehicle speed to determine the upstream segment of the intersection. The road speed ratio during the current time period; S304. Establish a linear functional relationship between the road speed ratio and the road segment traffic index, and calculate the upstream road segment in the general intersection. Traffic operation index of the road section.

3. The method for identifying traffic operation status at road intersections according to claim 2, characterized in that, In step S301, the preset time interval is 15 minutes, the preset number of days is not less than 20 days, and N=1 / 9; In step S302, the upstream road segment in the general intersection The formula for calculating the actual average speed of vehicles during the current time period is: , in, Upstream section of the intersection In the current period The actual average operating speed of vehicles within the vehicle; In the current period Inner Vehicles on the upstream section of the intersection The distance traveled; In the current period Inner Vehicles on the upstream section of the intersection The itinerary time; For the current time period Upstream section of the inner intersection Number of times the car was driven; In step S303, the upstream road segment in the general intersection The formula for calculating the road speed ratio in the current time period is: , in, Upstream section of the intersection In the current period The road operating speed ratio; Upstream section of the intersection The free flow velocity; In step S304, the linear functional relationship between the road operating speed ratio and the road segment traffic operation index is as follows: , in, Upstream section of the intersection Traffic operation index of the road section.

4. The method for identifying traffic operation status at road intersections according to claim 3, characterized in that, In step S3, the upstream road segment of the road intersection included in the general intersection is calculated. Corresponding import direction The process of calculating the intersection strength index is as follows: S311. Obtain the signal timing parameters of the road intersections included in the general intersection, including signal cycle and green light time, calculate the capacity of a single lane of the road intersection, and determine the capacity of the road intersection in the approach direction based on the lane configuration of the road intersection. The road capacity; S312. The road intersection obtained in step S1 is in the approach direction. Calculate the actual traffic flow at the road intersection in the approach direction. The ratio of actual traffic flow to road capacity is used to obtain the intersection's onward direction. The intersection strength index.

5. The method for identifying traffic operation status at road intersections according to claim 4, characterized in that, In step S311, the formula for calculating the traffic capacity of a single lane at a road intersection is: , in, This refers to the actual traffic capacity of a single lane at a road intersection within a general intersection. The signal cycle for road intersections within a general intersection; The green light time within the signal cycle; Road intersection on the inbound direction The formula for calculating road capacity is: , in, For road intersections in the general intersection category, the approach direction is... The road capacity; For road intersections in the general intersection category, the approach direction is... The number of lanes; In step S312, the road intersection is in the direction of the entrance. The formula for calculating the intersection strength index is: , in, For road intersections in the general intersection category, the approach direction is... The intersection strength index; For road intersections in the general intersection category, the approach direction is... Actual traffic flow.

6. The method for identifying traffic operation status at road intersections according to claim 1, characterized in that, In step S4, the formula for calculating the comprehensive traffic operation index of the general intersection is: , in, The comprehensive traffic operation index for intersections; Upstream section of the intersection Traffic operation index of the road section; For road intersections in the general intersection category, the approach direction is... The intersection strength index; and The preset weighting coefficients, This is the normalization factor.

7. The method for identifying traffic operation status at road intersections according to claim 6, characterized in that, The The value is 0.

4. The value is 0.6, the normalization factor. The value is 0.

24.

8. The method for identifying traffic operation status at road intersections according to claim 1, characterized in that, In step S5, the preset traffic operation status level classification criteria include: When the comprehensive traffic operation index of the intersection is less than the first threshold, it is judged to be in a smooth state; When the comprehensive traffic operation index of the intersection is greater than or equal to the first threshold and less than the second threshold, it is determined to be a slow-moving state. When the comprehensive traffic operation index of the intersection is greater than or equal to the second threshold and less than the third threshold, it is judged as a congested state. When the comprehensive traffic operation index of the intersection is greater than or equal to the third threshold, it is judged as a state of severe congestion.

9. The method for identifying traffic operation status at road intersections according to claim 8, characterized in that, The first threshold is 0.6, the second threshold is 0.8, and the third threshold is 1.

0.

10. A traffic operation status identification device for road intersections, characterized in that, The method for identifying the traffic operation status of a road intersection according to any one of claims 1 to 9 includes: The data acquisition module is used to acquire vehicle traffic data collected by various checkpoint devices deployed on the road network in the target area, preprocess the vehicle traffic data to obtain the actual traffic flow in each direction of the road intersection and the total traffic flow of the intersection, and calculate the vehicle passage time of each road segment. The road segment division module is used to divide urban roads into multiple general intersections based on the location information of each checkpoint device and its upstream and downstream relationships. Each general intersection includes a road intersection and the upstream road segment adjacent to that road intersection. The first index calculation module is used to calculate the upstream road segment in a general intersection. The road segment traffic operation index, and the road segments included in the general intersection and the upstream road segments Corresponding import direction The intersection strength index; The second index calculation module is used to perform weighted fusion based on the obtained road segment traffic operation index and intersection intensity index to obtain the comprehensive traffic operation index of the general intersection. The status determination module is used to preset the traffic operation status level classification standard, map the obtained comprehensive traffic operation index of the general intersection to the corresponding traffic operation status level, and output the recognition result.

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