Questions related to Traffic Engineering
Does anyone know if there are any reference values (i.e., thresholds, service levels) for urban planning practices and analysis, considering the following indicators?
1) criminality/criminal occurrences (*)
2) accidents between vehicles and pedestrians
3) average volume of motorized traffic (in urban areas)
Are there international standards, for example, from ISO or another institution? I would appreciate it if anyone could point out a reference source (link to an article, report, or standard) to support the information.
Thank you for your attention.
(*) For crime, I found only the Homicide Rate as a reference indicator (but without thresholds). This indicator seems to me to be extremely limiting since it ignores other types of crimes that are more common and affect more people, such as robberies (with or without weapons) and theft, in addition to neglecting sexual crimes and assaults (also grave) and vandalism (lighter). It seems that focusing only on homicides is reductionist and omits other risks to the population.
Calibrating a mic-simulation model is a tricky subject and I am working on calibrating SUMO model parameters. When I examined the literature on this subject, I did not come across a customized calibration approach for certain types of road networks. I will be glad to communicate and share information with those who have knowledge on this subject.
I'm interested in extracting the vehicles' trajectory of each vehicle during my simulation. I'm not sure if there is a way to export each vehicle trajectory (x, y, time-stamp). I'm considering a signalized intersection.
The boundaries of my investigations limits by real implementation on cities which are too far from driverless cars, ITS or other hyperllops-like decisions. I carefully examined,perhaps, all the existed models and approaches from japanees "Jamology", limitations of transport flows in the centre (of London,tax model), VANET, platooning, V2X, SCATS, SCOOT, traffic lights management and other methods which have some limitations from 'non detected' [without any sensors] vehicles (old cars, mini bus taxies or so-called "root taxy" , horses and carts , motocyclies, scooters, etc. or the bypass roads (which have exits in the centre of calculating zone and make some deviations in algorithms).
Not everything is solved by the development of public transport. In our city, it is planned to build a subway for 20 years, but the zones of the city are developed according to their own laws without taking into account the plans laid down for the metro, and therefore part of the dug canals under the ground do not meet today's needs.
Similarly, with the development of cycling and pedestrian zones. In countries with sharply continental weather in the cold season, it is unlikely that the city dweller will choose a bicycle instead of his personal car while the temperatures below 20 °C. Bus routes can have a certain effect, but again, dedicated lanes are needed (consider adjustments to the law and traffic regulations) and the replacement of a fleet for more comfortable trips as well as more developed routes. Inspection of road regulation(the police) is not as much interested in solving the problems of traffic congestion. The main indicator of the success of their work is the minimum number of accidents and victims on the roads. Therefore, the lower the traffic flow rate or its "standing", the calmer. Thus, what solution can really be implemented in cities where there are no autonomous and flying cars, where the budget is not enough to build monorails and tunnel stations (junctions) to connect metro, buses and other vehicles in rooms with comfortable conditions (for example, Queensland , New Zealand)?
the traffic light sometimes is easier to cause the traffic jam problem, if the designer don't make to many change to the both side of the road,such as the house and block building, what other aspect of things can be done to mitigate the traffic jam problem.
Intelligent Transportation Systems(ITS) are widely used in the world for traffic management. However, there are still many questions about the effective use of these systems. For example, are intelligent transportation systems used efficiently enough? Do different intelligent transportation systems have the ability to interact with each other? Is proactive control possible with traffic control centers? Can Artificial Intelligence be used for proactive work? Can the performance of the system or center be increased with artificial intelligence? I am curious about your ideas and/or experience on this subject.
I've been using python scripts to run vissim through the COM interface. I understand that there is a method to add user-defined methods to it. Particularly, I'm interested in running vissim in the background to reduce simulation turnaround time. As per the following webinar, it can be achieved by creating a 'HideVissim' extension in C# or F#.
They have uploaded their codes in Github which can be used directly. However, I'm unfamiliar with C#, F#, and .net. I'm struggling in implementing the suggested solution. I would be grateful if anyone could guide me through the process of adding those user-defined methods.
Every suggestion or comment is welcome. Thank you in advance.
Most car-following models were developed on the basis of some theory, observational studies, or a combination of the two. Many researchers have also used machine-learning algorithms such as neural networks and deep-learning for modeling car-following behavior. But machine-learning approaches are sometimes criticized because they are black-box models.
Would you use a neural network / deep-learning car-following model in simulations for investigating crash behavior/emissions / autonomous/connected or general car-following behavior? Please share your opinion. Thanks.
I used binary logistic regression to model the behavior of drivers' stop and go decision in dilemma zone. Now I have to estimate the elasticity of variables (corresponding change in outcome probability on changing one unit of X). My variables are of continuous and categorical nature. Any help would be highly appreciated.
P.S: I have uploaded the screenshot of one of the papers where author has calculated the elasticities.
I have traffic volume data collected over seven days (morning and evening daily) in 15-min intervals. I want to aggregate this seven-day (15 min counts) data into an hourly volume in order to visualize it through a heat map. Also, how to get AADT, ADT, DHV, and DDHV from this available data? Attached are the TMC sheets (All) in Excel/CSV format for seven days at an intersection (15-min interval counts).
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Please, feel free to share/disseminate this request. Thanks a lot for your attention and contribution. #SESAR #H2020 #SYN+AIR
What is distress? Why the distress is a problem?Typical Causes of the distress?
Probable solution to the Problem in Pakistan ?
Discuss Solution to Potholes in Pakistan.
hi everyone, I have developed a simulation of a roundabout with a fixed time regulation, the lines of traffic lights in the roundabout are for vehicle storage. my question is: when we regulate by tricolor light signals, should we make all the conflict zones inactive? and is it normal that we will have vehicles crossing each other? any help will be appreciated, thanks in advance
How Carpooling will reduce Traffic Congestion? I am researching on this in Islamabad.
What will be methodology to find out facts & figure?
Can any one suggest best software or Survey link which would be helpful.
I want to do publication on this topic.
As far as I know, the same plan might create different events when executed multiple times in MATSIM. But, I am looking for a way that whenever I run a particular scenario for my agents, the output will be the same. By output I mean, for example, the time when the agents arrive at their work or the time when they depart the traffic lights. I am wondering if it is possible to do so by means of seeds in MATSIM?
Does anyone know how we can model two different kinds of drivers on the conflict point (connector) at the highway exit ramp using microsimulation (VISSIM or Aimsun)? 1. drivers use the right-turn indicator to exit from the highway, 2. drivers do NOT use the right-turn indicator (violating drivers) but they are exiting from the highway. #VISSIM #TrafficModelling #Drivingbehaviour #Aimsum
I need some help with VISSIM. I have modeled an intersection where I would like to use no-changing lane rules near 100 ft of the traffic signal. Picture 1 shows intersection without applying lane change restriction, where vehicle 1 and vehicle 2 are changing lane near the traffic signal.
However, after applying no-lane change near the traffic signal, I found the picture 2 for EB direction. Actually, those two vehicles from picture 2 would like to turn left, but they are in no turning section. Therefore, they are not moving.
How may I apply no-lane changing near an intersection?
I have a link with multiple lanes; I want to calculate queue length on each lane at every timestep of a simulation run. I have explored the following options:
1) Makeshift method: creating separate links corresponding to each lane and define vehicle inputs separately. Insert the queue counter on each link. However, it would restrict lane change behavior.
2) Queue counter: It gives the maximum of queue length on individual lanes. I can apply a factor based on the vehicle turning ratio to estimate queue length on each lane.
3) Data collection points: Applying two such points on separate locations on each lane and processing the data from it. But, if vehicles changed lanes in between the two points, then it wouldn't give exact queue length
4) Node evaluation: Not sure how to implement it for each lane. I also suspect it will create an issue the same as the third point.
Let me know if you need any further clarification.
Any suggestions would be much appreciated! Thank you for your time.
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Dear colleagues in different fields of transport planning. I am currently conducting a study called "An integrated study of Park and Ride (P&R) facilities for sustainable urban mobility," which involves research and evaluation of the P&R system components in a mid-sized Latin American city. I have already researched the following: Land use, location of facilities, starting points for travel generation, catchment area, P&R demand, P&R capacity, dynamic accessibility, environment, interaction between (conventional, autonomous, electric vehicles with the P&R system)
I would like to know your opinion as transport planners, which other components should be taken into consideration. Thank you in advance for your feedback.
Intelligent transportation systems provide many advantages as part of our daily lives. One of the most common applications of these current and increasingly widespread systems in our cities is intelligent junction control. The scope of the intelligent junction control concept which includes different approaches and algorithms, is quite wide. It is known that it needs realistic and objective technical knowledge to guide decision makers correctly. In this sense, what do you think the definition of intelligent intersection should include? Is a high-cost intersection control system with a lot of equipment always necessary? Or are the lower cost solutions that enable multi-plan control by only increasing the number of control programs? What should be the threshold or the transition point for the preference? Is it sufficient to make only cost-benefit analysis? To what extent should social benefits be taken into account for feasibility analysis? Sharing your views on this issue can be beneficial to many researchers and interested parties and can contribute to the spread of sustainable transportation (traffic management) systems.
Speaking about the benefits and disadvantages of public transport many responded that the most annoying things about this service are waiting time (frequency), the accessibility of the transport (especially for people with disability) and the number of transfers. My question is: What could be the solution to all these problems? We don't want to use private cars since that would lead to a traffic problem (which we want to avoid). Have you heard of any "collective transport 2.0" that could improve the existing one?
I have 15-minutes traffic volume count data at different locations along a highway stretch. With this data, I want to calculate ADT and AADT.
My question is about vehicle behavior, mainly lane changing and conflict area behavior. the network is heavily congested across the simulation period, and the goal is to have this same behavior in vissim.. that is, vehicles diverge/merge/or cross as normal in case of free flow, and slowly enter the conflict one car at a time in the case of congestion (later on the simulation period)
first, i have set up a conflict area with the priority to the major road and the minor ramp can enter (avoid block major disabled), and a priority rule with zero gap and 5m headway for congestion case. unfortunately this didn't work.. i tried changing the type to undetermined, but this caused one car at the major to wait so long while all the cars on the ramp cross (it is supposed to keep the cars in their original sequence but that didn't work for me)
Also, the highlighted vehicle in the picture waits (for lane changing) before the conflict marker leaving empty space downstream, how to prevent this?
second, in the 4 lane highway shown in the second picture. the actual behavior is as follows: cars that want to change to the right lane to follow their static route manage to change lanes over a long distance smoothly. in vissim however, all lanes have cars that want to change lanes and they suddenly stop (at lane change distance and emergency distance) and cause unrealistic queues upstream that reduces the flow rate significantly. i tried increasing the lane change distance but this only moved the problem upstream.. is their a way to prevent the [Right turn decision makers] from remaining on the left lane, or to let them change lanes one lane at a time rather than stopping at the emergency distance and causing the entire highway to stop.
Many vehicle barriers use things like water containment to slow and stop vehicles. Those barriers do not move like a swing gate, sliding gate, or rotating gate. What are some of the effective ways to stop a vehicle using a movable barrier?
I want to calculate traffic density of roadways near intersections and also midblock sections on urban roads. I have video recordings for different locations. So, I want to know about any reliable methods to calculate road density from the videos.
The existing route direction of vehicles ( please check figure in below) in a city has been drawn for a research. Are the number of conflicts at each intersection drawn correctly? Would anyone kindly evaluate the drawing and give any suggestion?
N.B: Please name the intersection as CMM, PMM, KGM, TM, IM
I am looking for guidance, white papers and scholarly articles about road diets on an arterial street with an annual average daily traffic (AADT) above 45,000 and a peak hour volumes of 4,000 and greater.
In my thesis, I used queueing theory, in order to evaluate the traffic conditions of a intersection, which produced waiting time, service time etc for vehicles approaching the intersection from each road. Now, a question arise in my mind that can I use this type of data for Intelligent Transportation Systems (ITS).
Hi, I am working on the simulations of Aw and Rascle second order model for traffic flow, the model does not produce stable results, Why is that so ?
The numerical scheme is stable, i have checked the scheme for other models, it is quite good.
I wanted to know the advantages of data mining techniques are, when compared with macroscopic traffic flow models, microscopic models, simulation models for transportation traffic congestion prediction? Which one has a higher performance data mining techniques like decision tree, SVM or simulation approaches or simple travel time and speed prediction approaches?
AASHTO (2001) talks about a value of 4.5 m/sec2 as it was observed that most of the drivers decelerate at a rate greater than 4.5 m/sec2 when decelerating for an unexpected condition.This value may or may not be applicable for Indian Traffic condition which is highly heterogeneous in nature. This situation is characterized by different vehicle categories with diverse static and dynamic characteristics, changing composition, lack of lane discipline. Does it mean that I need to use different DR values for different category of vehicles under different traffic facility? I could not get hold of accident reconstruction specialist who could have helped me in this regard. Kindly advise.
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There will be 1-2 PhD Student Positions available in the Department of Modeling, Simulation & Visualization Engineering (MSVE) at Old Dominion University. Students are expected to work on Transportation Research projects, with a focus on Data Analytics, Artificial Intelligence (AI)/Machine Learning, Virtual/Augmented Reality (VA/AR), Transportation System Modeling & Simulation, and/or Transportation Safety.
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Thank you very much!
I do not have access to sources , I need papers on topics like "Is induced traffic measured by survey ? " and other topics in this regard ! Thanks
here in Afghanistan we do not access to these sources !
How much the size of spatial area affects traffic generation within the area and the resulting traffic volumes in the relevant city (public transport or individual transport)?
Is there any method of theoretical approach how to describe this issue?
I want to model a data center and its connections to end user by adding number of hops(switches/routers) in between showing a geographically far data center location from its client and another data center with proximity near to the client. Taking all parameters into consideration like latency due to various reasons in both cases and comparing them. I want to add software defined networks in between the data center and end user. kindly suggest me some tool in which i can design a complete network with opion of choosing the type of wires , routing algorithms etc. so that we can optimally deliver the cloud traffic to end user.
Different stakeholders of transportation system are often found concerned with different aspects of it. For instance,
- The traveller or commuter thinks about what will be the travel time on a particular route? Whether he/she will be able to reach the destination in time?
- The transportation manager thinks about how the system performed yesterday? which locations are the worst performers?
- The traffic engineer thinks about the locations of congestion hotspots and the peak hours for various routes.
- The planners and researchers think about what will be the travel demand in future and how they can address it.
Based on their concerns, they have different expectations from the "Intelligent Transportation System". I am looking for these expectations from different perspectives especially for developing countries like India.
is there any research work for finding the optimal number of parking bays for the estimated parking demand? which can help in finding the number of parking bays for the given duration....
The default values for the CC Parameters in PTV VISSIM are for the simulation of freeway traffic. As I want to simulate Urban Traffic using the Wiedemann 99 Modell, I am looking for a set of Parameters that better reflects the driving Behavior in an urban environment.
Differentiated Services Traffic Engineering is one of the most effective technique for QoS provision in scalable distributed multimedia networks.
I have found quite a few studies on this topic that have been conducted in developed countries. [viz (Sutermeister, 1956), Pretty (1973), May and Montgomery (1988), Mahalel, Gur and Shiftan (1991), Ye, Veneziano and Lassacher (2008) etc]. As manual traffic control is only used for emergencies and special occasions in developed countries, not many studies are done compared to other hot topics. But in Asian countries, manual traffic control is quite common, but, I could not find any studies related to this topic. Can anyone suggest me a few if its available?
I am curently working on a research which requries the modeling of a single lane roundabout in VISSIM. I am teaching my self throught the process however, I am stuck with the process of setting the priority rules and the conflicting areas. So, I have the following questions;
1- Is the "Min Gap" parameter/input in VISSIM represents (same as) the "Critical Headway" in the Highway Capacity Manual ?
2- In VISSIM, if you set the priority rules for a single-lane roundabout, do you still have to set the conflicting areas or the priority rules will take care of it ?
3- What is the best procedure for setting the priority rules of a sinlge-lane roundabout in VISSIM ? In other words, what is the recommended input vaues for the "Min Gap" & "Headway" to model in VISSIM ?
I would highly appreciate if anyone could provide me with links to videos or helpfull sources for setting or modeling priority rules of single-lane roundabouts in VISSIM.
Hi, I was working on TRANSCAD and had confusions about creating the link O-D matrix for the larger networks based on the data obtained from the trip tables. I wanted to work on the Chicago Regional Network and I downloaded the trip tables from (http://www.bgu.ac.il/~bargera/tntp/). But somehow I am unable to make O-D matrix for the network. Any help would be appreciated.
I want to compare almost 100 matrices. I want to know how different is a11 to b11 to c11.... The matrix itself is 2000 X 2000 matrix.
My understanding so far from literature is that I can compare these matrices to see whether matrices are different to each other or not. I am more interested in seeing whether the cells ( within matrices) are different to each other or not and if yes, by how much?
Puffin signal crossings are based on sensors for pedestrian detection. What are the different type of senors/image processing tools which can be used to detect pedestrians at a crossing location for installing a low cost puffin signal?
Grading of bitumen is done based on performance and it depends on maximum and minimum location temperatures values of implementation of pavement and traffic load.
I am working on creating a random road traffic generator, so far i've seen so many random traffic generators either on commercial software or open source software, but i can't seem to figure out how random is it? is there a control on how the arrival generation is done in order to show some phenomenon, like periodicity.
In my case I am working on generating traffic coming from a signalized intersection. while using a distribution with parameters fitted using real data, by generating random Time Headway between vehicles i can't see the periodicity, however when i add a control on how much vehicles should be generated in each period (let's call it the phase in the preceding intersection) using a poisson distribution and after that making sure to not generated Time Headways that would not be more than then the period duration and also not respecting the amount of vehicles generated in a period for computation efficiency (in order to not have the computer do too much loops and take more time in the traffic generation) I can clearly see the periodicity phenomenon. But scientifically speaking is this not interfering with the random generation and adding a bias to my generated data ?
In occupancy vs. speed graphs for different modes (cars, motorbikes and rickshaws), the R-squared values were quite low (22.7% to 47.7%), although a clear correlation can be seen.
As car-following is an extension of human behavior, which itself is highly random, low R-squared values were expected. What are some studies that can help me justify these low values? What are ideal ranges for such values in studies in car-following and human behavior in transportation? And if I were to remove outliers to improve the values, how many can I remove?
Currently, we are working on the safety assessment at signalized intersections under Indian traffic condition which is highly heterogeneous in nature. At the selected study sites, some amount of vehicles are violating the red lights i) which stand in the front positions of the queue and start moving/entering the intersection before the signal turns green (we are referring to them as red light violations at the end of red phase) ii) after yellow time i.e. at the beginning of red phase a few vehicles are entering the intersection. We have prepared the network in VISSIM, but we are unable to generate the situations of red light violation in VISSIM. Any suggestions/advice regarding the above-mentioned problem will be greatly appreciated. Thanks in advance.
I want to predict the future position of a vehicle in a two dimensional road. The number of lanes are varying over the stretch of the road and I want to predict the future position of the vehicle(the position(may be x & y coordinate and the lane number) during the simulation. The position should be calculated while the simulation is running. The vehicles are free to change lanes in case of lane reduction. Is there any way to predict the positions dynamically during the simulation?
Thank you in advance!
if we have LAN topology consist from (25) host and (5) switch , is any way to know how many ARP Request Generated by typical host in this LAN topology ?
I am working on optimization approaches on an intersection. And I have been getting some questionnable results on the simulator. I get some high troughputs of vehicle in the intersection but with big average delay of vehicles e.g :
In a scenario I get a throughput of 4544 with an average delay of 31.22 seconds and average queue length per phase of 41 meters
And in another scenario I get a 4551 throughput with an average delay of 31.26 seconds with an average queue length per phase of 39.68 meters
This compared to the average study of the same intersection we see different results, e.g in a scenario a throughput of 4343 with an average delay of 30.7 seconds and an average queue length per phase of 21.1 meters.
I am starting to question my results performance. Doesn't higher throughput mean minimum average delay and lesser queues on lanes ?
I am collecting details on how roads are defined in terms of class or hierarchy in different countries. It's not so straightforward as might be thought. Results so far (and posted elsewhere online) are for New Zealand, India and Tanzania. Any help with information for other countries would be much appreciated.
I am working on Vehicular Networks and on a problem that is concerned with the %age of public buses in metropolitan cities.
What would be the safe assumption to make as to what is the percentage of public buses of the total vehicular density in urban scenarios? Somewhere I read that public buses would be 25 to 30% of the total vehicular density in the urban scenarios, but I cannot find the reference.
Any resource and/or reference would be highly appreciated.
I have 140 samples data about driver driving , and want to divided them into specific number of types,such as three .
I have already try to do that ,use a 1X3 map (SOM) in matlab nctool to divide them into 3 types , and consider that each neuron represent one center of the type.
Does it is proper to do that ?
Thanks for attention !
Could you share with me this documents to compare characteristics like classification (primary, secondary, etc.), road width, lane width, separators, sidewalks dimensions, etc, with the real conditions of the roads in my city?
Thanks for your help!
I am modelling a 4 lane signalized roundabout in a country using right hand drive using a VISSIM microscopic traffic simulation model
Do you remember the lovely hostesses and their beautiful tricycles in the opening ceremony of Rio 2016 Olympic Games? They are so cool! But do you know how many accidents related to tricycles? Now I'm studying the frequency, characteristics, severity and factor correlation of the accidents involving tricycles based on hundreds of crash cases. Here, the tricycles include man-power type and electric type. In China, these vehicles are very common and popular on roads. But now I hardly find any paper regarding this. Could you recommend some related papers for me? Thanks in advance.