A method and device for determining missing time of trajectory points on a highway
By determining the duration distribution function of road segments with missing trajectories and optimizing the objective function, the problem of determining the missing time of trajectory points on highways was solved, thus improving the accuracy of trajectory point identification.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- LIAONING COMM TECH CO LTD
- Filing Date
- 2023-03-24
- Publication Date
- 2026-06-12
AI Technical Summary
On highways, due to factors such as poor signal, excessive vehicle speed, and environmental weather, existing technologies cannot accurately determine the time of missing trajectory points, resulting in reduced accuracy in trajectory point recognition.
By determining the duration distribution function based on the historical travel time of vehicles of the same model on road segments with missing trajectories, and using the Lagrange multiplier algorithm to optimize and solve the objective function, the target duration of road segments with missing trajectories is determined, and finally the missing time of trajectory detection points is determined.
It improves the accuracy of completing missing time in trajectory points and enhances the accuracy of trajectory point recognition.
Smart Images
Figure CN116311942B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of traffic facility technology, and in particular to a method and apparatus for determining the missing time of detection trajectory points on highways. Background Technology
[0002] With social development and technological advancements, an increasing number of vehicles are appearing on highways. Antennas for Electronic Toll Collection (ETC) and Manual Toll Collection systems are typically installed on highway gantries or checkpoints to record the actual driving trajectories of vehicles and calculate highway tolls. Fixed cameras at fixed locations on highways also identify vehicles and perform trajectory reconstruction or vehicle verification. However, regardless of the technology used, issues such as poor signal strength, excessive vehicle speed, and environmental weather conditions can cause some missed identifications. Consequently, it becomes impossible to determine the time corresponding to missing trajectory points on highways, thus reducing the accuracy of trajectory point identification. Summary of the Invention
[0003] In view of this, the purpose of this application is to provide a method and apparatus for determining the missing time of detection trajectory points on highways, which can determine the missing time information of trajectory detection points corresponding to the missing trajectory of a target vehicle on a highway, thereby improving the accuracy of completing missing trajectory points.
[0004] This application provides a method and apparatus for determining the missing time of detected trajectory points on a highway. The method and apparatus for determining the missing time of detected trajectory points on a highway include:
[0005] For any missing trajectory segment corresponding to the target vehicle, the duration distribution function corresponding to the missing trajectory segment is determined based on the historical travel time of each vehicle of the same type on the highway.
[0006] Based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment, determine the objective function corresponding to all the missing trajectory segments;
[0007] The objective function is optimized and solved to determine the target duration for the target vehicle in each of the missing trajectory segments;
[0008] Based on the target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory road segment, the missing time information of the trajectory detection points corresponding to the target vehicle on each trajectory missing road segment is determined.
[0009] Furthermore, determining the duration distribution function corresponding to each missing trajectory segment based on the historical travel time of each vehicle of the same model on each missing trajectory segment on the highway includes:
[0010] Based on the historical travel time of each vehicle of the same type on the highway for the missing trajectory segment, determine the expected historical travel time and the variance of the historical travel time corresponding to the missing trajectory segment;
[0011] Based on the expected historical travel time and the variance of historical travel time, the duration distribution function corresponding to each of the missing trajectory segments is determined.
[0012] Furthermore, determining the objective function corresponding to all the missing trajectory segments based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment includes:
[0013] Based on each duration distribution function and the number of missing trajectory segments, determine the initial function corresponding to all the missing trajectory segments;
[0014] Based on the initial function and the target duration constraints corresponding to each of the missing trajectory segments, the objective function corresponding to all the missing trajectory segments is determined.
[0015] Furthermore, determining the objective function corresponding to all the missing trajectory segments based on the initial function and the target duration constraints corresponding to each of the missing trajectory segments includes:
[0016] Based on the initial function and the target duration constraints corresponding to each missing trajectory segment, the maximum value of the initial function is determined to be the standard function corresponding to all the missing trajectory segments;
[0017] Logarithmic calculation is performed on the standard function to determine the objective function corresponding to all the missing trajectory segments.
[0018] Furthermore, the optimization solution for the objective function to determine the target duration for the target vehicle in each of the missing trajectory segments includes:
[0019] The objective function is optimized using the Lagrange multiplier algorithm to determine the target duration for the target vehicle in each of the missing trajectory segments.
[0020] Furthermore, the formula for the duration distribution function is:
[0021]
[0022] Where μ is used to characterize the expected historical travel duration; σ2 The variable t is used to represent the variance of historical travel time; t is used to represent the travel time corresponding to each missing track segment.
[0023] Furthermore, before determining the duration distribution function corresponding to the missing trajectory segment based on the historical travel time of vehicles of the same model on the highway for any missing trajectory segment corresponding to the target vehicle, the method for determining the missing time of the detected trajectory points on the highway further includes:
[0024] The highway is divided into sections, and each section of the highway and the corresponding trajectory detection point for each section are determined. The sections include sections with missing trajectories and sections with normal trajectories.
[0025] This application embodiment also provides a device for determining the missing time of detected trajectory points on highways, the device comprising:
[0026] The first determining module is used to determine the duration distribution function corresponding to any missing trajectory segment for the target vehicle, based on the historical travel time of each vehicle of the same type on the missing trajectory segment on the highway.
[0027] The second determining module is used to determine the objective function corresponding to all the missing trajectory segments based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment.
[0028] The third determining module is used to optimize and solve the objective function to determine the target duration of the target vehicle in each of the missing trajectory segments;
[0029] The fourth determining module is used to determine the missing time information of the trajectory detection points corresponding to the target vehicle on each missing trajectory segment based on the target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory segment.
[0030] This application also provides an electronic device, including: a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus. When the machine-readable instructions are executed by the processor, the steps of the method for determining the missing time of detection trajectory points on a highway as described above are performed.
[0031] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the method described above for determining the missing time of detection trajectory points on a highway.
[0032] The method and apparatus for determining the missing time of trajectory points on highways provided in this application, compared with the existing methods for detecting trajectory points on highways, utilize the historical travel time of the target vehicle on each trajectory-missing section of the highway to determine the duration distribution function corresponding to each trajectory-missing section. Based on the duration distribution function, the number of trajectory-missing sections, and the target duration constraints corresponding to each trajectory-missing section, the objective function corresponding to all trajectory-missing sections is determined. The objective function is then optimized to determine the target duration of the target vehicle on each trajectory-missing section. Based on the target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory section, the missing time information of the trajectory detection points corresponding to the target vehicle on each trajectory-missing section is determined. This improves the accuracy of completing missing trajectory points.
[0033] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0034] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0035] Figure 1 This document illustrates one of the flowcharts for a method to determine the missing time of a detected trajectory point on a highway, as provided in an embodiment of this application.
[0036] Figure 2 This document illustrates a structural diagram of one embodiment of a method for determining the missing time of a detection trajectory point on a highway, as provided in this application.
[0037] Figure 3 The second flowchart illustrates a method for determining the missing time of a detection trajectory point on a highway, as provided in an embodiment of this application.
[0038] Figure 4A schematic diagram of the structure of a device for determining the missing time of a trajectory point on a highway, provided in an embodiment of this application, is shown.
[0039] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of this application is shown.
[0040] In the picture:
[0041] 400 - Device for determining the missing time of trajectory points detected on highways; 410 - First determining module; 420 - Second determining module; 430 - Third determining module; 440 - Fourth determining module; 450 - Fifth determining module; 500 - Electronic device; 510 - Processor; 520 - Memory; 530 - Bus. Detailed Implementation
[0042] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. Based on the embodiments of this application, every other embodiment obtained by those skilled in the art without inventive effort falls within the scope of protection of this application.
[0043] First, the applicable scenarios for this application will be introduced. This application can be applied to the field of transportation infrastructure technology.
[0044] Research has revealed that with social development and technological advancements, an increasing number of vehicles are appearing on highways. Antennas for Electronic Toll Collection (ETC) and Mobile Testing Center (MTC) are typically installed on highway gantries or checkpoints to record vehicle trajectories and calculate tolls. Fixed cameras at specific locations on highways also identify vehicles and perform trajectory reconstruction or vehicle verification. However, regardless of the technology used, issues such as poor signal strength, excessive vehicle speed, and weather conditions can lead to missed identifications. Consequently, it becomes impossible to determine the time corresponding to missing trajectory points on highways, thus reducing the accuracy of trajectory point identification.
[0045] Furthermore, in existing technologies, the closed nature of highways makes it relatively simple and certain to complete the location of missing trajectory points, but the completion of the time corresponding to the trajectory points is relatively uncertain. However, knowing the time corresponding to the trajectory points is of great significance for analyzing traffic flow in different time periods.
[0046] Based on this, this application provides a method for determining the missing time of detection trajectory points on highways, which can determine the missing time information of trajectory detection points corresponding to the missing trajectory of a target vehicle on a highway, thereby improving the accuracy of completing missing trajectory points.
[0047] Please see Figure 1 , Figure 1 This is one of the flowcharts for a method to determine the missing time of detection trajectory points on a highway, provided as an embodiment of this application. Figure 1 As shown in the figure, the method for determining the missing time of detection trajectory points on highways provided in this application embodiment includes the following steps:
[0048] S101. For any missing trajectory segment corresponding to the target vehicle, determine the duration distribution function corresponding to the missing trajectory segment based on the historical travel time of each vehicle of the same type on the highway for the missing trajectory segment.
[0049] The missing trajectory section is used to characterize the section where the target vehicle's driving trajectory is missing during its journey on the highway.
[0050] In this step, the highway is first divided into sections, including sections containing vehicles of the same model and vehicles of different models. Each section of the highway (including sections with missing trajectories and sections with normal trajectories) and the corresponding trajectory detection points are determined. Then, for any section with missing trajectories corresponding to the target vehicle, the historical travel time of each vehicle of the same model on the highway for the section with missing trajectories is obtained. Based on the historical travel time of each vehicle of the same model on each section with missing trajectories, the duration distribution function corresponding to the section with missing trajectories is determined.
[0051] Here, the highway gantries or checkpoints on the highways where the target vehicle is located are equipped with electronic toll collection (ETC) devices to identify vehicles. These ETC devices are used to determine the actual trajectory of the target vehicle on each road segment.
[0052] ETC (Electronic Toll Collection) is an automatic toll collection system for highways or bridges. It involves a dedicated short-range communication between an on-board electronic tag installed on the windshield of the target vehicle and a microwave antenna in the ETC lane at the toll station. It uses computer networking technology to conduct back-end settlement with banks, thereby enabling the target vehicle to pay highway or bridge tolls without stopping at the toll station.
[0053] Specifically, the duration distribution function provided in this application can be a Gaussian distribution function, and the formula for the Gaussian distribution function is:
[0054]
[0055] Where μ is used to characterize the expected historical travel duration; σ 2 The variable t is used to characterize the variance of historical travel time, and t is used to characterize the travel time corresponding to each missing track segment.
[0056] In the above, it is assumed that the historical travel time needs to satisfy a Gaussian distribution function.
[0057] Here, the Gaussian distribution function is the most common type of random distribution, also known as the normal distribution.
[0058] Assume that the duration of each missing track segment satisfies the duration distribution function.
[0059] S102. Based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment, determine the objective function corresponding to all the missing trajectory segments.
[0060] In this step, after determining the duration distribution function corresponding to each missing trajectory segment of the target vehicle on the highway, the objective function corresponding to the target vehicle in all missing trajectory segments is determined based on the duration distribution function parameters in each duration distribution function, the number of missing trajectory segments in the actual driving trajectory of the target vehicle on the highway, and the constraints on the target duration corresponding to each missing trajectory segment.
[0061] In the embodiments provided in this application, the target duration constraint conditions corresponding to each trajectory missing road segment can be specific but not limited to: the missing time information of the trajectory detection point corresponding to the target vehicle on each trajectory missing road segment is equal to the time information of two trajectory detection points that are sequentially adjacent to the missing time information of the above trajectory detection point on the normal trajectory road segment.
[0062] Optionally, step S102 includes the following sub-steps:
[0063] Sub-step 1021: Determine the initial function corresponding to all the missing trajectory segments based on each duration distribution function and the number of missing trajectory segments.
[0064] Here, we assume that the road segments where the target vehicle's trajectory is missing are [a1, a2, a3, ..., a n ], and assume that the historical travel time of each missing track segment is [t1, t2, t3, ..., t n For road segment a, then i The corresponding target duration t i The probability is:
[0065]
[0066] Furthermore, the initial function corresponding to all missing road segments (the product of the probabilities of travel time for all missing road segments) is as follows:
[0067]
[0068] Sub-step 1022: Determine the objective function corresponding to all the missing trajectory segments based on the initial function and the target duration constraints corresponding to each missing trajectory segment.
[0069] In the embodiments provided in this application, the target duration constraint conditions corresponding to each trajectory missing road segment can be specific but not limited to: the missing time information of the trajectory detection point corresponding to the target vehicle on each trajectory missing road segment is equal to the time information of two trajectory detection points that are sequentially adjacent to the missing time information of the above trajectory detection point on the normal trajectory road segment.
[0070] Thus, step 1022 includes the following sub-steps:
[0071] Sub-step 10221: Based on the initial function and the target duration constraints corresponding to each missing trajectory segment, determine the maximum value of the initial function as the standard function corresponding to all missing trajectory segments.
[0072] Sub-step 10222: Perform logarithmic calculation on the standard function to determine the objective function corresponding to all the missing trajectory segments.
[0073] Please refer to Figure 2 , Figure 2 This document illustrates a structural diagram of one embodiment of a method for determining the missing time of detection trajectory points on a highway, as provided in this application. Figure 2 As shown, vehicle 1 and vehicle 2 are both target vehicles, and Figure 2The diagram shows that a highway is divided into four segments a1, a2, a3, a4 in a certain direction and five trajectory detection points g1, g2, g3, g4, g5. Vehicle 2 can be detected by all trajectory detection points. Therefore, the embodiment provided in this application only needs to test vehicle 1 among the target vehicles. The position of vehicle 1 at the trajectory detection points between trajectory detection points g1 and g4 can be uniquely determined by matching with the highway network, that is, the position of trajectory detection points g2 and g3. However, the time taken to pass through trajectory detection points g2 and g3 is uncertain.
[0074] Furthermore, the target travel time for the missing road segments in the embodiments provided in this application is specifically the time it takes for vehicle 1 to pass through road segments a1, a2, and a3.
[0075] The standard functions corresponding to all the trajectory missing road segments in the embodiments provided in this application can be specifically as follows:
[0076]
[0077] so, and These are used to characterize the target vehicle passing through trajectory detection point g1 and trajectory detection point g, respectively. n+1 The time is the time it takes for vehicle 1 to pass through trajectory detection points g1 and g4.
[0078] In the above, for ease of calculation, the natural logarithm of the standard function corresponding to the missing trajectory segment is taken to obtain a new objective function with constraints (st), the specific formula of which is:
[0079] objective: max ln(L(t1, t2, t3,…,t n ))
[0080]
[0081] S103. Optimize and solve the objective function to determine the target duration of the target vehicle in each of the missing trajectory segments.
[0082] Optionally, the step of optimizing the objective function to determine the target duration for the target vehicle in each of the missing trajectory segments includes:
[0083] The objective function is optimized using the Lagrange multiplier algorithm to determine the target duration for the target vehicle in each of the missing trajectory segments.
[0084] Specifically, the optimization solution using the Lagrange multiplier algorithm can be achieved by constructing a Lagrange function and finding its maximum value.
[0085] Here, the constructed Lagrange function can be specifically defined as:
[0086] In this step, a Lagrange multiplier λ is introduced to construct a Lagrange function, and the optimization of the objective function is transformed into the optimization of the Lagrange function, that is, to find the partial derivative of the Lagrange function with respect to each parameter, resulting in the following system of equations:
[0087]
[0088] Thus, the solution to the system of equations is calculated as follows:
[0089]
[0090] Among them, t1, t2, t n The target duration corresponding to each missing segment of the trajectory is used to characterize the Lagrange function.
[0091] S104. Based on the target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory road segment, determine the missing time information of the trajectory detection points corresponding to the target vehicle on each trajectory missing road segment.
[0092] In this step, after calculating the target duration corresponding to each missing trajectory segment, the missing time information of the trajectory detection points corresponding to the target vehicle on each missing trajectory segment can be easily obtained. For example, it can be specifically as follows: Figure 2 As shown, the positions of trajectory detection points g2 and g3 on the missing trajectory segments are given. The specific time information for the missing trajectory detection points for the target vehicle on each missing trajectory segment is as follows:
[0093]
[0094]
[0095] The method for determining the missing time of trajectory points on highways provided in this application, compared with the existing trajectory point detection methods, utilizes the historical travel time of the target vehicle on each trajectory-missing section of the highway to determine the duration distribution function corresponding to each trajectory-missing section. Based on the duration distribution function, the number of trajectory-missing sections, and the target duration constraints corresponding to each trajectory-missing section, the objective function corresponding to all trajectory-missing sections is determined. The objective function is then optimized to determine the target duration of the target vehicle on each trajectory-missing section. Based on each target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory section, the missing time information of the trajectory detection points corresponding to the target vehicle on each trajectory-missing section is determined. This method can determine the missing time information of the trajectory detection points corresponding to the target vehicle on the highway, thus improving the accuracy of completing missing trajectory points.
[0096] Please see Figure 3 , Figure 3 This is a second flowchart illustrating a method for determining the missing time of detection trajectory points on a highway, provided as an embodiment of this application. Figure 3 As shown in the figure, the method for determining the missing time of detection trajectory points on highways provided in this application embodiment includes the following steps:
[0097] S301. Based on the historical travel time of each vehicle of the same type on the highway for the missing trajectory segment, determine the expected historical travel time and the variance of the historical travel time corresponding to the missing trajectory segment.
[0098] In this step, with Figure 2 For example, taking road segment a1 as an example, the expected historical travel time corresponding to road segment a1 is: Variance of historical travel time corresponding to road segment a1
[0099] Here, the historical passage duration in this embodiment can be set to...
[0100] S302. Based on the expected historical travel time and the variance of historical travel time, determine the duration distribution function corresponding to each of the missing trajectory segments.
[0101] The historical travel time of the missing trajectory road segment is used to characterize the historical travel time of other vehicles besides the target vehicle on the road segment.
[0102] S303. Based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment, determine the objective function corresponding to all the missing trajectory segments.
[0103] S304. Optimize and solve the objective function to determine the target duration of the target vehicle in each of the missing trajectory segments.
[0104] S305. Based on the target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory road segment, determine the missing time information of the trajectory detection points corresponding to the target vehicle on each trajectory missing road segment.
[0105] The descriptions of S303 to S305 can be referred to the descriptions of S102 to S104, and can achieve the same technical effect, so they will not be elaborated further.
[0106] The method for determining the missing time of trajectory points on highways provided in this application, compared with the existing trajectory point detection methods, utilizes the historical travel time of the target vehicle on each trajectory-missing section of the highway to determine the duration distribution function corresponding to each trajectory-missing section. Based on the duration distribution function, the number of trajectory-missing sections, and the target duration constraints corresponding to each trajectory-missing section, the objective function corresponding to all trajectory-missing sections is determined. The objective function is then optimized to determine the target duration of the target vehicle on each trajectory-missing section. Based on each target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory section, the missing time information of the trajectory detection points corresponding to the target vehicle on each trajectory-missing section is determined. This method can determine the missing time information of the trajectory detection points corresponding to the target vehicle on the highway, thus improving the accuracy of completing missing trajectory points.
[0107] Please see Figure 4 , Figure 4 This is a schematic diagram of a device for determining the missing time of trajectory points on a highway, provided as an embodiment of this application. Figure 4 As shown, the device 400 for determining the missing time of detection trajectory points on the highway includes:
[0108] The first determining module 410 is used to determine the duration distribution function corresponding to any missing trajectory segment for the target vehicle, based on the historical travel time of each vehicle of the same type on the missing trajectory segment on the highway.
[0109] Optionally, the first determining module 410 is specifically used for:
[0110] Based on the historical travel time of each vehicle of the same type on the highway for the missing trajectory segment, determine the expected historical travel time and the variance of the historical travel time corresponding to the missing trajectory segment.
[0111] Based on the expected historical travel time and the variance of historical travel time, the duration distribution function corresponding to each of the missing trajectory segments is determined.
[0112] The second determining module 420 is used to determine the objective function corresponding to all the missing trajectory segments based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment.
[0113] Optionally, the second determining module 420 is specifically used for:
[0114] Based on the duration distribution function and the number of missing trajectory segments, determine the initial function corresponding to all the missing trajectory segments.
[0115] Based on the initial function and the target duration constraints corresponding to each of the missing trajectory segments, the objective function corresponding to all the missing trajectory segments is determined.
[0116] Optionally, based on the initial function and the target duration constraints corresponding to each of the missing trajectory segments, the objective function corresponding to all the missing trajectory segments is determined, including:
[0117] Based on the initial function and the target duration constraints corresponding to each missing trajectory segment, the maximum value of the initial function is determined to be the standard function corresponding to all the missing trajectory segments.
[0118] Logarithmic calculation is performed on the standard function to determine the objective function corresponding to all the missing trajectory segments.
[0119] The third determining module 430 is used to optimize and solve the objective function to determine the target duration of the target vehicle in each of the missing trajectory segments.
[0120] Optionally, the step of optimizing the objective function to determine the target duration for the target vehicle in each of the missing trajectory segments includes:
[0121] The objective function is optimized using the Lagrange multiplier algorithm to determine the target duration for the target vehicle in each of the missing trajectory segments.
[0122] Optionally, the formula for the duration distribution function is:
[0123]
[0124] Where μ is used to characterize the expected historical travel duration; σ 2The variable t is used to represent the variance of historical travel time; t is used to represent the travel time corresponding to each missing track segment.
[0125] The fourth determining module 440 is used to determine the missing time information of the trajectory detection points corresponding to the target vehicle on each missing trajectory segment based on the target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory segment.
[0126] The fifth determining module 450 is used to divide the highway into sections, determine each section of the highway and the trajectory detection point corresponding to each section, wherein the sections include sections with missing trajectories and sections with normal trajectories.
[0127] The device 400 for determining the missing time of trajectory points on highways provided in this application embodiment, compared with the trajectory point detection method in the prior art, determines the duration distribution function corresponding to each trajectory missing segment by utilizing the historical travel time of the target vehicle on each trajectory missing segment of the highway. Based on the duration distribution function, the number of trajectory missing segments, and the target duration constraint conditions corresponding to each trajectory missing segment, the objective function corresponding to all trajectory missing segments is determined. The objective function is then optimized and solved to determine the target duration corresponding to the target vehicle on each trajectory missing segment. Based on each target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory segment, the missing time information of the trajectory detection points corresponding to the target vehicle on each trajectory missing segment is determined. This improves the accuracy of completing missing trajectory points.
[0128] Please see Figure 5 , Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 5 As shown, the electronic device 500 includes a processor 510, a memory 520, and a bus 530.
[0129] The memory 520 stores machine-readable instructions executable by the processor 510. When the electronic device 500 is running, the processor 510 and the memory 520 communicate via the bus 530. When the machine-readable instructions are executed by the processor 510, they can perform the operations described above. Figure 1 as well as Figure 3 The steps of the method for determining the missing time of the detection trajectory points on the highway in the method embodiment shown are described in detail in the method embodiment, and will not be repeated here.
[0130] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, can perform the above-described actions. Figure 1 as well as Figure 3 The steps of the method for determining the missing time of the detection trajectory points on the highway in the method embodiment shown are described in detail in the method embodiment, and will not be repeated here.
[0131] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.
[0132] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the shown or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.
[0133] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0134] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.
[0135] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0136] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The scope of protection of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A method for determining the missing time of detection trajectory points on a highway, characterized in that, The method for determining the missing time of the detected trajectory points on the highway includes: For any missing trajectory segment corresponding to the target vehicle, the duration distribution function corresponding to the missing trajectory segment is determined based on the historical travel time of each vehicle of the same type on the highway. Based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment, determine the objective function corresponding to all the missing trajectory segments; The objective function is optimized and solved to determine the target duration for the target vehicle in each of the missing trajectory segments; Based on the target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal road segment, the missing time information of the trajectory detection points corresponding to the target vehicle on each missing road segment is determined; The formula for the duration distribution function is as follows: ； Where µ is used to characterize the expected historical travel time. The variable used to characterize the historical travel time variance is t, which is used to characterize the travel time corresponding to each missing track segment. The step of determining the objective function corresponding to all the missing trajectory segments based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment includes: Based on each duration distribution function and the number of missing trajectory segments, determine the initial function corresponding to all the missing trajectory segments; Based on the initial function and the target duration constraints corresponding to each of the missing trajectory segments, determine the objective function corresponding to all the missing trajectory segments; The objective function is: in, and These are used to characterize the trajectory detection points of the target vehicle. and trajectory detection points The historical duration is L ( ) is the likelihood function.
2. The method for determining the missing time of detection trajectory points on highways according to claim 1, characterized in that, The step of determining the duration distribution function corresponding to the missing trajectory segment based on the historical travel time of each vehicle of the same model on the highway for the missing trajectory segment includes: Based on the historical travel time of each vehicle of the same type on the highway for the missing trajectory segment, determine the expected historical travel time and the variance of the historical travel time corresponding to the missing trajectory segment; Based on the expected historical travel time and the variance of historical travel time, the duration distribution function corresponding to the missing trajectory segment is determined.
3. The method for determining the missing time of detection trajectory points on highways according to claim 1, characterized in that, The step of determining the objective function corresponding to all the missing trajectory segments based on the initial function and the target duration constraints corresponding to each of the missing trajectory segments includes: Based on the initial function and the target duration constraints corresponding to each missing trajectory segment, the maximum value of the initial function is determined to be the standard function corresponding to all the missing trajectory segments; Logarithmic calculation is performed on the standard function to determine the objective function corresponding to all the missing trajectory segments.
4. The method for determining the missing time of detection trajectory points on a highway according to claim 1, characterized in that, The optimization solution for the objective function, determining the target duration for the target vehicle in each of the missing trajectory segments, includes: The objective function is optimized using the Lagrange multiplier algorithm to determine the target duration for the target vehicle in each of the missing trajectory segments.
5. The method for determining the missing time of detection trajectory points on a highway according to claim 1, characterized in that, Before determining the duration distribution function corresponding to the missing trajectory segment based on the historical travel time of vehicles of the same model on the highway for any missing trajectory segment corresponding to the target vehicle, the method for determining the missing time of the detected trajectory points on the highway further includes: The highway is divided into sections, and each section of the highway and the corresponding trajectory detection point for each section are determined. The sections include sections with missing trajectories and sections with normal trajectories.
6. A device for determining the missing time of a detection trajectory point on a highway, characterized in that, The device for determining the missing time of the detected trajectory points on the highway includes: The first determining module is used to determine the duration distribution function corresponding to any missing trajectory segment for the target vehicle, based on the historical travel time of each vehicle of the same type on the missing trajectory segment on the highway. The formula for the duration distribution function is as follows: ； Where µ is used to characterize the expected historical travel time. The variable used to characterize the historical travel time variance is t, which is used to characterize the travel time corresponding to each missing track segment. The second determining module is used to determine the objective function corresponding to all the missing trajectory segments based on each of the duration distribution functions, the number of missing trajectory segments, and the target duration constraints corresponding to each missing trajectory segment, including: Based on each duration distribution function and the number of missing trajectory segments, determine the initial function corresponding to all the missing trajectory segments; Based on the initial function and the target duration constraints corresponding to each of the missing trajectory segments, determine the objective function corresponding to all the missing trajectory segments; The objective function is: in, and These are used to characterize the trajectory detection points of the target vehicle. and trajectory detection points The historical duration is L ( ) is the likelihood function; The third determining module is used to optimize and solve the objective function to determine the target duration of the target vehicle in each of the missing trajectory segments; The fourth determining module is used to determine the missing time information of the trajectory detection points corresponding to the target vehicle on each missing trajectory segment based on the target duration and the time information of the trajectory detection points corresponding to the target vehicle on the normal trajectory segment.
7. An electronic device, characterized in that, include: The device includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus. The machine-readable instructions are executed by the processor to perform the steps of the method for determining the missing time of a detection trajectory point on a highway as described in any one of claims 1 to 5.
8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of the method for determining the missing time of a detection trajectory point on a highway as described in any one of claims 1 to 5.