68 results about "Degree of saturation" patented technology

The invention relates to a traffic signal control system, in particular to a multiple key intersection optimization technology applied in the traffic signal control system for a regional road network. According to the technical proposal of the invention, the optimization technology comprises: a. divide the intersection traffic into three status comprising light traffic, medium traffic and heavy traffic; b. determine a public cycle of a sub-area according to a key intersection group formed by a plurality of intersections with high traffic saturation degree; in calculating the public cycle under coordinated control in the sub-area, conduct automatic sorting of the saturation degree of all the intersections under control in the sub-area in each time section; select a plurality of intersections with top ranking into the key intersection group; c. select sample volume and comprehensively consider the representativeness of sample and calculate the workload. Therefore, the invention is able to resolve the problem of poor adaptability and low efficiency in the single key intersection optimization technology of existing traffic signal control system.

The invention discloses a forecasting method for a port area short-time traffic flow under a model of reservation cargo concentration in port, which belongs to the technical field of port area traffic management. The method comprises the following steps of: dividing traffic generation regions and attract regions, and obtaining the sub-period distribution rule of historical traffic in various traffic generation regions and attract regions; determining the traffic attract regions and the traffic volume; determining the corresponding back storage yards, obtaining the distribution of the traffic generation regions and the traffic volume; determining the relevant section at the upstream of the forecast road section according to the extension length at the opposite direction of the upstream-road traffic flow of the forecast road section in forecast periods; establishing a knowledge base; measuring the turn rate for the upstream/downstream road sections in each forecast period in real time; extracting the turn rate for the upstream/downstream road sections of the turn rate of the traffic flow in former Nz periods before the current forecast period p; estimating the weighted turn rate in the former Nz short-time forecast periods; calculating the inflow comprehensive saturations in the forecast road section li; generating the traffic flow forecast state vector; searching a road sectiontraffic flow corresponding to the generated state vector in the knowledge base, forecasting the traffic flow of the forecast road section in the next period of the current forecast period p; generating new search strategy, and updating the knowledge base. The invention can be used for short-time traffic flow forecast, and avoids generation of large congestion points and spreading of congestion regions.

The invention discloses a method and device for priority control of a tramcar. The method includes: acquiring a priority request of the tramcar; determining a traffic saturation degree of an intersection from which the tramcar is about to drive in; if the traffic saturation degree of the intersection is not greater than a first threshold value, executing first priority control operation on priority phase of the tramcar; if the traffic saturation degree of the intersection is greater than the first threshold value and less than a second threshold value, executing second priority control operation on the priority phase; if the traffic saturation degree of the intersection is greater than the second threshold value, not executing priority control on the priority phase. Priority control modes of the tramcar are automatically selected according to the traffic saturation degree, and period compensation is performed after priority control, so that priority effect of the tramcar can be improved to greatest extent on the premise that passing benefit of social vehicles is ensured.

The invention provides a multiple strategies based traffic control method and system. The method comprises the following steps that S1) city roads are divided into traffic control subareas, and corresponding control strategies are executed according to different saturation degrees of the road network of the traffic control subareas; S2) the control strategy is adjusted according to the average vehicle occupancy of different roads and the average saturation degree of a corresponding crossing in the road network of the traffic control subarea; and S3) green light time of key roads in the trafficcontrol subareas with inconsistent states is adjusted, so that the traffic state of each traffic control subarea is consistent. The different traffic control subareas are divided, the traffic conditions of the road network, roads and crossings of the subareas are taken into integrated consideration, different controls strategies are selected for different traffic states, the traffic condition inthe traffic control subarea is evaluated, and the green light time of key roads is adjusted.

The invention provides a variable lane signal control method based on a multi-traffic index. By acquiring real-time traffic data and signal control data, the queuing length of a green light starting moment, the queuing length of a green light ending moment, the green light duration and traffic characteristic data of the saturation during the green light are obtained; and when the obtained trafficcharacteristic data reach the respective threshold condition and a variable lane guide attribute switching interval meets a prescribed interval duration, the variable lane guidance triggers a switching request signal, evaluates the influence of the variable lane guidance attribute switching on the traffic pressure before and after the switching, and determines whether to perform the variable laneguidance attribute switching. By applying the variable lane signal control method provided by the invention, the problem that real traffic adjustment requirements cannot be accurately reflected by a single index can be avoided, the influence of the lane guidance adjustment on the traffic flow operation is evaluated in advance, manual and automatic switching of the lane guidance attribute is supported, the method is more in line with an actual traffic operation rule, the lane operation efficiency of intersections is improved, and the overflow and confusion risks caused by queuing is reduced.

The invention discloses a dynamic traffic influence evaluation method for an urban road construction period. The method comprises the following steps: S1, determining a traffic influence range of an urban road construction project; S2, acquiring and processing mobile phone signaling data, filtering and denoising the data by matching the base station with the mobile phone signaling data, establishing a user position state table by collecting data in real time, and updating the latest state in real time; S3, setting parameters of a training set and a test set, and predicting the traffic volume and the vehicle speed by using a long-short-term memory neural network; S4, employing VISSIM software to simulate and analyze the saturation of each road section in different construction periods, thequeuing length of the signalized intersection, the average travel time and the average delay, and evaluating the traffic flow operation states in different construction stages. According to the invention, a set of complete dynamic traffic influence evaluation method is formed, and decision support is provided for traffic construction and management departments to implement traffic organization design in different construction stages.

The invention relates to a method for analyzing morning-evening rush hour congestion conditions and propagation mechanism of road network based on Granger causality. The method comprises the following steps of: 1) establishing a time sequence of the traffic state of an intersection: modeling road intersections by adopting a dual method, taking a road section as a node, abstracting the intersections as edges between the nodes, preprocessing traffic state data, sorting out a directional intersection all-day saturation time sequence, selecting congestion time in the morning and evening rush hours, and selecting a traffic state time sequence with a set length forwards; 2) constructing a road network congestion propagation relationship network based on Granger causality; 3) searching key nodes based on the average out-degree and the average in-degree of the nodes, introducing a dynamic propagation model, fitting the congestion propagation process of the road network, and constructing a traffic congestion propagation mechanism of the road. The method is simple and beneficial to software implementation, and the result can be applied to traffic state analysis and traffic guidance and control systems.

The invention relates to a system and a method for road traffic detection based on an inspection well cover, which is used for solving a problem that inspection well covers on traffic lanes are not sufficiently utilized at present. The system comprises an inspection well cover and is characterized by further comprising a display terminal, wherein the inspection well cover is provided with an infrared detector, a pressure detector, a wireless transmitter and a controller, the infrared detector, the pressure detector and the wireless transmitter are connected to the controller, and the wireless transmitter is connected with the display terminal through a wireless network. The traffic saturation is calculated through computing the time spent by a vehicle when passing the inspection well cover in unit time. According to the invention, current resources are sufficiently utilized, detected information is sent to the display terminal, and the system can be applied to various traffic detection or traffic detection software, thereby facilitating people to know and monitor traffic conditions of each road segment, being capable of providing useful data for urban traffic management, and being also capable of providing data for users. The users can make a better driving route according to the data, and a circumstance of congestion is avoided.

The invention relates to a road traffic detection system and method based on manhole covers so as to solve the problem that the manhole covers on a lane are not made full use of. The system comprises the manhole covers and a display terminal. Each manhole cover is equipped with an infrared detector, a pressure detector, a wireless emitter and a controller, wherein the infrared detector, the pressure detector and the wireless emitter are connected to the controller; and the wireless emitter is connected with the display terminal through a wireless network. Traffic saturation degree of the lane is summarized by calculating time used by vehicles passing across the manhole cover every unit time. According to the road traffic detection system and method, the current resources are fully utilized to allow the detected information to be sent to the display terminal, and the road traffic detection system and method can be utilized to various traffic detection or traffic detection software, thereby allowing people to know and monitor the road traffic conditions of each road section conveniently; and the road traffic detection system can provide useful data for urban traffic management, and can also provide data for users, so that the users can select better driving routes based on the data, and traffic jam cases can be prevented.

The invention relates to a traffic state thermogram visualization method based on traffic saturation, and belongs to the technical field of traffic. The method includes acquiring the point data of a video, a coil, a geomagnetic field in the traffic management, and calculating the saturation of the intersection and the road section in the road network, adopting an average clustering analysis method, dividing the class of all the saturation in the road network, and calculating the values of the saturation in various classes again, and selecting the point distribution density degree of the thermogram according to the saturation average value so as to obtain the traffic state thermogram based on the traffic saturation. The method has the advantages that the operation is simple, the calculationis convenient, and the defect that the proportion of the track data is small, the precision is low or the traffic state cannot be effectively displayed under the condition of ineffective acquisitioncan be made up, and meanwhile, the condition of the traffic bearing capacity of the intersection and the road section is considered, the traffic state can be visually displayed more fully and reasonably, and a support is provided for the scheme decision of the traffic manager.

The invention discloses an audit method for a bus network optimization scheme based on a traveler visual angle. The method comprises two stages: evaluation before influence of an initial bus network optimization scheme and evaluation after optimization of a bus network. In the previous evaluation stage, constructing a bus transfer influence index BAI based on the passenger flow transfer saturationand the travel time extension ratio; dividing the influence degree into three levels according to the BAI index, evaluating the influence degree of the initial scheme on related travelers, and proposing corresponding correction feedback suggestions. In the post-evaluation stage, from two aspects of the network and the line, after the scheme is implemented, the actual passenger flow transfer condition and the travel characteristic change of the common passengers on the line are concerned, and the result influencing the pre-evaluation and the application effect of the bus line network optimization method are tracked and fed back. According to the invention, support is provided for realizing a bus network optimization scheme based on the traveler visual angle.

The invention discloses an intersection control time period and phase timing design and closed-loop verification method. An existing intersection time period division method is broken through, and thefinal purpose is to serve for signal phase timing design. Intersection control time period and signal phase timing integrated design is carried out according to traffic flow change trends of different flow directions of the intersection, and the intersection control time period and signal phase timing design is verified by parameters such as traffic flow direction saturation, so that the rationality of the intersection control time period and phase timing design is further improved, the intersection vehicle delay is reduced, and the traffic efficiency is improved.

The invention relates to a fee collection control method for ensuring the traffic quality of a specific lane. The method comprises the steps of defining the update period of a lane fee collection standard as N days, and keeping the lane fee collection standard within one period to be unchanged; according to the traffic congestion degree, formulating an initial lane fee collection standard, whereinthe fee collection is xp for each duration of t0 during the peak period, and the fee collection is xf for each duration of t0 during the mean peak period; calculating the lane saturation degrees of aplurality of time periods during the peak period is calculated by utilizing bayonet data, figuring out the average value of all the saturation degrees, and recording the average value as the lane saturation degree of the peak period; defining the target value of the lane saturation degree to be a maximum saturation degree of the lane traffic flow under the free-flow state. A difference value Epsilon p is adopted as an evaluation index of the road traffic condition during the peak period, and the evaluation index is used for evaluating the coincidence degree of the lane traffic current situation compared with the target value. According to the evaluation index Epsilon p of the peak period and a fee collection regulation factor theta p, the lane access fee xp for each duration of t0 duringthe peak period is adjusted. In the same way, the lane access fee xf for each duration of t0 during the mean peak period is adjusted.

The invention discloses a method for determining an expressway lane management and control strategy based on a congested road section. The method comprises the steps: collecting traffic data through an expressway detector, and converting the queuing length into the traffic volume per unit hour; under the condition that the sum of the actual traffic capacity per unit hour of the congested road section and the traffic volume per unit hour converted from the queuing length cannot exceed the actual traffic capacity per unit hour of the downstream area, determining the saturation value of emergency lane opening of the congested road section; and determining an emergency lane opening end point according to whether the remaining unit hour traffic capacity of the downstream area under the condition that the emergency lane is not opened can meet the unit hour traffic volume of the emergency lane, and further determining the emergency lane opening length. According to the method, the vehicles in the congested road section can be timely dissipated, the highway traffic efficiency is improved, the open length of the emergency lane is reasonably determined, the waste of emergency resources caused by opening the emergency lane for a too long distance is avoided, and a scientific decision-making method is provided for opening the emergency lane to solve the traffic congestion problem.

The invention discloses an inductive control method for multi-objective optimization under the constraint of real-time queuing length of vehicles. The inductive control method comprises the steps of 1) acquiring intersection traffic data in real time; 2) conducting data preprocessing; 3) establishing an optimization model by taking minimum total delay, minimum parking times and maximum traffic capacity as objectives; 4) carrying out model constraint condition determination and parameter calibration; and 5) obtaining a real-time optimization optimal period, and distributing the maximum green light time of an induction signal control model according to the real-time requirement of each phase. According to the method, under different traffic requirements, the built multi-objective optimization model can well improve the operation efficiency of the intersection, and the improvement effect is most obvious especially when the saturation degree is high. The proposed optimization model breaksthrough the limitation that the maximum green light time of a traditional induction signal is fixed, can better improve the control efficiency of induction signal control, better adapts to traffic changes of an intersection in different time periods, and meets the random changing traffic requirements.

The invention provides a road section interruption state judgment method and system, and belongs to the technical field of traffic operation management, and the method comprises the steps: obtaining the historical traffic flow between portal pairs; calculating boundary thresholds of the historical traffic flow under different characteristic conditions based on the historical traffic flow; and judging whether the real-time traffic flow between the portal pairs is equal to zero or not, if so, judging whether the real-time traffic flow between the portal pairs is lower than a boundary threshold value or not, and if not, judging that the road traffic between the portal pairs is in an interrupted state. According to the invention, the problems of false report, missing report and untimely report of the sampling data are avoided; the problem that only the slow or congested state of the road section can be judged according to the designed speed of the highway, the average speed of the road section and the saturation is solved; according to the method, a traffic flow boundary condition calculation method is provided, interruption state judgment conditions are established, the situation that the road section between the gantries is mistakenly judged to be in an interruption state can be effectively avoided, and the accuracy of judgment of the interruption state of the road section is improved.

The invention provides a construction area unloading point utilization grade evaluation method based on refined traffic management, which comprises the following steps: further converting saturation into utilization indexes according to space information and use conditions of each unloading point in a construction area, and calculating the utilization grade of each unloading point on the basis of the time utilization indexes of the unloading points and the time interval space utilization indexes of a building. The calculated and analyzed space-time utilization index and space-time equilibrium index of each building are used, and the utilization grade of each building is evaluated; and on the basis of the time utilization index of each building and the time period space total utilization index of the construction area, calculating a space-time utilization index and a space-time equilibrium index of the construction area, and finally evaluating the space-time utilization level of the construction area. According to the invention, the time and space of the construction area are subjected to refined traffic management, the influence of different saturations is quantified by using an index concept, the utilization level is determined through the space-time utilization index and the space-time equilibrium index, the existing problem is determined, and corresponding suggestions and measures are searched.

The invention discloses a single-point signalized intersection optimization timing method based on Fisher ordered clustering. The method comprises the steps of: extracting historical traffic flow data, and carrying out dimension reduction processing, and obtaining a dimension-reduced historical traffic flow matrix; taking a row vector of the dimension-reduced historical traffic flow matrix as a sample, and segmenting the sample by adopting the Fisher ordered clustering to obtain an optimal segmentation number and a segmentation mode corresponding to the optimal segmentation number, and taking the optimal segmentation number and the segmentation mode as an optimal control time period; and carrying out an optimal timing simulation experiment on the optimal control time period to obtain an optimal timing scheme. According to the method, the traffic efficiency of an intersection can be improved under the condition of high saturation of the intersection; The method overcomes the high requirements of an existing adaptive control method for infrastructures such as hardware and algorithms, and has the advantages of low cost and high reliability.

The invention provides a judgement method of setting conditions of pedestrian two-step street crossing, and a timing optimization method of pedestrian two-step street crossing. The judgement method comprises the steps of: judging whether an intersection meets a traditional setting condition of a pedestrian two-step street crossing facility, and determining the weight of the traditional setting condition according to the judgment result; comparing the pedestrian saturation with a preset saturation threshold, and determining the weight of the pedestrian saturation according to the comparison result; comparing a vulnerable group proportion with a preset proportion threshold in the traffic composition, and determining the weight of the vulnerable group proportion according to the comparison result; calculating a total setting condition coefficient of pedestrian two-step street crossing according to the weight of the traditional setting condition, the weight of the pedestrian saturation andthe weight of the vulnerable group proportion, and determining whether the pedestrian two-step street crossing facility needs to be disposed at the intersection according to the total setting condition coefficient. By adopting the judgement method provided by the invention, a wider judgment condition is provided for the setting of two-step street crossing, and a corresponding timing scheme is provided for the signal control of two-step street crossing.

The invention provides a drainage method and system for a road parallel section, electronic equipment and a storage medium, and relates to the technical field of traffic equipment.The method comprises the steps: obtaining vehicle data obtained through monitoring in monitoring equipment, wherein the monitoring equipment is arranged at a shunting starting point and a shunting terminal point of the road parallel section, and according to the vehicle data, calculating the current traffic saturation in each parallel road of the road parallel section, and if the traffic saturation exceeds a saturation threshold limited by the reference saturation of the corresponding parallel road in the road parallel section, comparing the traffic saturation in each parallel road of the road parallel section, and obtaining saturation contrast among parallel roads in the road parallel section, if the saturation contrast exceeds a set comparison threshold value, determining guide data according to the saturation contrast, and sending the guide data to the display equipment arranged before the shunting starting point so that the display equipment displays the guide data.

The invention discloses a method for quickly generating an intersection signal timing scheme tending to target saturation in the field of traffic signals, which comprises the following steps of: S1, acquiring traffic flow parameters of each direction group of an intersection, and defining straight traffic flow in each direction and left-turn traffic flow in the opposite direction as a conflict traffic flow pair; s2, based on the traffic flow ratio, counting a key traffic flow combination K formed by the conflict traffic flow pairs of each direction group and a corresponding non-key traffic flow combination Knot, and selecting the key traffic flow combination K with the maximum flow ratio sum and the corresponding non-key traffic flow combination Knot as target objects; s3, adjusting the green light time of each traffic flow in the key traffic flow combination K in the target object according to the expected saturation, and determining a signal control period; and S4, adjusting the green light time of each traffic flow in the non-key traffic flow combination Knot in the target object according to the expected saturation and the direction green light total time. The method has no application limitation, and the optimization result is fast and accurate.