Pedestrian Traffic Flow Research Articles

Using Social Media for Attendees Density Estimation in City-Scale Events

City-scale events attract large amounts of attendees in temporarily re-purposed urban environments. In this setting, the real-time measurement of the density of attendees stationing in—or moving through—the event terrain is central to applications, such as crowd management, emergency support, and quality of service evaluation. Sensing or communication infrastructures (e.g., sensor networks and mobile phones) can be deployed to estimate the number of attendees currently occupying an area. However, the adoption of these technologies is hindered by their cost or sensing resolution. There is evidence that social media data can provide a real-time and semantically rich insight into attendees’ behavior during city-scale events. Their suitability as a data source for attendees density estimation is yet to be investigated. With this paper, we aim at filling this knowledge gap by studying how micro-posts harvested from social media can be used during city-scale events to estimate the density of attendees in a given terrain. To cope with issues of temporal and spatial resolution, we propose three classes of density estimation strategies (i.e. geo-based, speed-based, and flow-based) inspired by elements of pedestrian traffic flow theory that were successfully assessed during city-scale events. We study the performance of these strategies in the context of SAIL Amsterdam 2015 (Sail) and Kingsday Amsterdam 2016 (Kingsday), two city-scale events that attracted 2 and 1.5 million of attendees in the span of five days and one day, respectively. We defined four experimental terrains for the Sail event and one for the Kingsday event, and compare density estimates from social media data with measures obtained from counting systems and Wi-Fi sensors. Results show the potential of solutions embedding elements from pedestrian traffic flow theory, which yielded estimates with strong temporal correlations with the sensor observation, and limited mean errors.

Reducing the impact of speed dispersion on subway corridor flow

The rapid increase in the volume of subway passengers in Beijing has necessitated higher requirements for the safety and efficiency of subway corridors. Speed dispersion is an important factor that affects safety and efficiency. This paper aims to analyze the management control methods for reducing pedestrian speed dispersion in subways. The characteristics of the speed dispersion of pedestrian flow were analyzed according to field videos. The control measurements which were conducted by placing traffic signs, yellow marking, and guardrail were proposed to alleviate speed dispersion. The results showed that the methods of placing traffic signs, yellow marking, and a guardrail improved safety and efficiency for all four volumes of pedestrian traffic flow, and the best-performing control measurement was guardrails. Furthermore, guardrails’ optimal position and design measurements were explored. The research findings provide a rationale for subway managers in optimizing pedestrian traffic flow in subway corridors.

A large-scale controlled experiment on pedestrian walking behavior involving individuals with disabilities

It is imperative to design walking facility infrastructures to accommodate the needs of all pedestrian, including individuals with disabilities. Unfortunately, individuals with disabilities are often overlooked due to the lack of available data. The purpose of this study was to measure the individual pedestrian walking behaviors of individuals with disabilities through controlled video tracking experiments of heterogeneous crowds in various walking facilities; including passageways, right and oblique corners, doorways, bottlenecks, and stairs. The goal of this paper is to provide an overview of conducting experimental research on pedestrian walking behavior involving individuals with and without disabilities, including automated video tracking methods, data collection, logistical issues, processing methods, and lessons learned from conducting a large-scale study. The findings support future large-scale experiments related to the pedestrian walking behavior of individuals with disabilities. The results can be used to calibrate and validate pedestrian traffic flow models capturing the behaviors and interactions of crowds which include different types of individuals with disabilities.

An Improved Speed-Density Relationship Model for Pedestrian Flow

The speed-density relationship performs as a basis to realize the behavior of a complex system such as vehicular or pedestrian traffic flow. Based on the speed-density relationship, the relationships between other pedestrian characteristics such as speed-flow, flow-density and speed-pedestrian module could be derived. Compared to vehicular flow, very little research has been done to develop a general model to describe pedestrian speed-density relationship. The widely used exponential speed-density models, the Underwood model and the Drake model show that the maximum flow is obtained at jam density, which is illogical because at jam density the movement is very limited and the speed will be at its minimum level. In this study, we propose an improved deterministic speed-density model for pedestrian flow which is an important contribution in the field of pedestrian studies. The proposed model shows that the maximum flow occurs at a density which is less than the jam density and thus, overcoming the limitations of the existing models. The validity of the model is empirically verified by primary and secondary datasets. The results showed that the proposed model can describe the speed-density relationship for all the datasets that were collected for different scenarios such as indoor and outdoor facilities. This model can be used as a general speed-density relationship.

Pedestrian road safety in relation to urban road type and traffic flow

Abstract The paper presents an analysis of the relationship between pedestrian road safety, urban road type and motorists’ traffic flow. A suitable index for the evaluation of the walkability level of an urban street is the pedestrian traffic flow and the walking behavior. The researchers examined six urban streets of various types in the city of Volos (a medium-sized Greek city, 130,000 inhabitants). They collected data of the pedestrian traffic flow and their legal or illegal walking behavior for each road segment of the examined streets. Furthermore, they collected data of motorists’ traffic flow in the same road segments of the streets in the study area. The combination of those data with the administrative ranking of each road can indicate a walkability level of an examined street or a specific route and reveal pedestrians’ mobility and safety issues. This study supports that walking behavior differs for various road types. Pedestrians with the highest rate of legal behavior were presented in main arterials (91.8%) and the lowest one in local streets (53.7%). Low level of motorized traffic flow in combination with maintenance and mobility problems in pedestrian infrastructure incites pedestrians to walk in the street thus underestimating their safety issues. Promotion of pedestrian mobility emphasizing in safety issues can change the modal split in favor of vulnerable road users, increase the sustainability index of an urban area and improve the citizens’ quality of life.

Reducing the noise pollution level along main roads in Sibiu, Romania by optimizing the traffic flow

Noise pollution is one of the most important negative effects of road traffic, especially in cities. The current paper presents an attempt to reduce the noise level created by the road traffic along some main roads in the city of Sibiu, Romania by suggesting ways to optimize the traffic flow. The number of cars and the resulting noise levels were recorded in a key area of Sibiu. The noise levels were compared to standards and to measurements taken in areas with less traffic. Then, they were fed, together with road geometry data, into a specialized simulation software that allowed the computer-aided reproduction of the traffic flow, but also the modifying of conditions such as the road geometry to achieve, coupled with a multicriterial analysis, an optimization of the pedestrian and road traffic flow in view of a reduced noise pollution.

보행교통류 시뮬레이션 모형을 활용한 보행편의성 지표의 개발 및 분석

보행교통류의 통행은 다른 교통수단과 비교하여 더 미시적인 움직임을 보인다. 정해진 차선의 구분 없이 통행하므로 2차원적인 움직임을 보일 수 있으며, 자유로운 방향전환 능력을 통해 이동할 수 있다. 이러한 이유로 보행교통류의 편의성을 평가하는 방법에 있어서도 보행교통류의 미시적인 특성이 반영되어야 한다고 할 수 있다. 만일 보행자만의 행태를 반영하여 편의성을 평가할 수 있다면 보행교통류의 통행 특성을 더 원활히 파악할 수 있을 것이다. 이에 본 연구에서는 보행교통류의 특성을 반영하여 편의성을 판단할 수 있는 지표들을 시뮬레이션을 통해 제시하였다. 본 연구에서는 경로이탈도, 속도의 변화 크기, 그리고 충돌 횟수라는 세 편의성 지표를 통해 보행교통류의 편의성을 평가할 수 있음을 보였다. 각각의 지표들은 보행교통류의 고유한 통행 특성을 해석할 수 있으면서도, 교통류율의 변화에 따라 서로 다른 함수 형태를 보였다. 결과적으로 기존의 교통유율이나 속도와 더불어서 LOS를 판단할 수 있는 보조 지표로 활용될 수 있음을 알 수 있었다. The pedestrian traffic flow has more complicated microscopic features than vehicular traffic flow. Without any designated lanes or any guidance, pedestrians naturally move and change their routes in two dimensional domain with ease. Thus the assessment of pedestrian comfort level should be considering the microscopic features of pedestrian flow. This study is aimed at developing pedestrian comfort criteria based upon pedestrian flow simulation model. This study suggests three criteria to determine pedestrian comfort level; the deviation of route, the acceleration of walk, and the number of collision. Each criterion, which can address the unique walking patterns of pedestrian flow, is represented as each different function with respect to traffic flow rate. The criteria can be the additional indicators to determine the level of service of pedestrian flow together with traffic flow rate and walking speed.

SIMULTANEOUS DETECTION AND TRACKING OF PEDESTRIAN FROM PANORAMIC LASER SCANNING DATA

Pedestrian traffic flow estimation is essential for public place design and construction planning. Traditional data collection by human investigation is tedious, inefficient and expensive. Panoramic laser scanners, e.g. Velodyne HDL-64E, which scan surroundings repetitively at a high frequency, have been increasingly used for 3D object tracking. In this paper, a simultaneous detection and tracking (SDAT) method is proposed for precise and automatic pedestrian trajectory recovery. First, the dynamic environment is detected using two different methods, <i>Nearest-point</i> and <i>Max-distance</i>. Then, all the points on moving objects are transferred into a space-time (<i>x</i>, <i>y</i>, <i>t</i>) coordinate system. The pedestrian detection and tracking amounts to assign the points belonging to pedestrians into continuous trajectories in space-time. We formulate the point assignment task as an energy function which incorporates the point evidence, trajectory number, pedestrian shape and motion. A low energy trajectory will well explain the point observations, and have plausible trajectory trend and length. The method inherently filters out points from other moving objects and false detections. The energy function is solved by a two-step optimization process: tracklet detection in a short temporal window; and global tracklet association through the whole time span. Results demonstrate that the proposed method can automatically recover the pedestrians trajectories with accurate positions and low false detections and mismatches.

SIMULTANEOUS DETECTION AND TRACKING OF PEDESTRIAN FROM PANORAMIC LASER SCANNING DATA

Abstract. Pedestrian traffic flow estimation is essential for public place design and construction planning. Traditional data collection by human investigation is tedious, inefficient and expensive. Panoramic laser scanners, e.g. Velodyne HDL-64E, which scan surroundings repetitively at a high frequency, have been increasingly used for 3D object tracking. In this paper, a simultaneous detection and tracking (SDAT) method is proposed for precise and automatic pedestrian trajectory recovery. First, the dynamic environment is detected using two different methods, Nearest-point and Max-distance. Then, all the points on moving objects are transferred into a space-time (x, y, t) coordinate system. The pedestrian detection and tracking amounts to assign the points belonging to pedestrians into continuous trajectories in space-time. We formulate the point assignment task as an energy function which incorporates the point evidence, trajectory number, pedestrian shape and motion. A low energy trajectory will well explain the point observations, and have plausible trajectory trend and length. The method inherently filters out points from other moving objects and false detections. The energy function is solved by a two-step optimization process: tracklet detection in a short temporal window; and global tracklet association through the whole time span. Results demonstrate that the proposed method can automatically recover the pedestrians trajectories with accurate positions and low false detections and mismatches.

Optimization Technique for Pedestrian Data Extraction

Data extraction is an essential part of traffic flow parameter estimation. Estimation of traffic flow parameters, such as flow rate, density, and speed are carried out under certain measurement interval. Fundamental relationships among these parameters and capacity analysis are sensitive to the choice of appropriate measurement interval. In this study the impact of different measurement intervals on the results of pedestrian traffic flow parameter estimation have been compared to arrive at an optimized time interval. Analysis has been carried out with measurement intervals of 15 seconds, 30 seconds and 60 seconds. Based on the variation in estimated parameters the optimized measurement interval can be defined to improve pedestrian traffic flow modeling process. From the analysis it was observed that for small interval, extracted data were more scattered in nature and resulted in lesser coefficient of determination. For density data extraction it was observed that density can be estimated using the linear relationship between speed-density rather than extraction from video. In this process data extraction time can be reduced. Analysis proposed in this paper shall be useful in optimizing resources for pedestrian flow analysis.

An Investigation Capability Model for Bidirectional Pedestrian Flow

<p class="zhengwen"><span lang="EN-GB">The pedestrian traffic flow in bidirectional walkways is very crucial aspect influenced by the level of pedestrians’ decisions.</span><span lang="EN-GB"> In this article, the authors show that the simulated pedestrians walking based on crowd dynamics models of low level mechanism of navigation (operational level) are short-sighted in avoiding counter flow. Such limitation resulted in unrealistic formation of motion in bidirectional flow, that the movement is less systematic and the lanes are less coherent than what in real situation. To obtain a more representative model, the authors improve the investigation capability model as a tactical decision model to be incorporated into a crowd dynamics model to reproduce better formation of motion. This is accomplished by granting the pedestrians the ability to investigate the macroscopic behaviors in their investigation areas and make decisions for convenience flow. The new model considers the average density and flow inside such areas and models their effect on the pedestrians' decisions. Simulations are performed to validate the work qualitatively by tracing the behavior of the simulated pedestrians and studying the impact of this behavior on the self-organized phenomenon: lane formation. Furthermore, the fundamental diagram of bidirectional flow is reproduced and compared with experimental fundamental diagrams.</span></p>

Continuum theory for pedestrian traffic flow: Local route choice modelling and its implications

This contribution puts forward a novel multi-class continuum model that captures some of the key dynamic features of pedestrian flows. It considers route choice behaviour on both the strategic (pre-trip) and tactical (en-route) level. To achieve this, we put forward a class-specific equilibrium direction relation of the pedestrians, which is governed by two parts: one part describing the global route choice, which is pre-determined based on the expectations of the pedestrians, and one part describing the local route choice, which is a density-gradient dependent term that reflects local adaptations based on prevailing flow conditions.Including the local route choice term in the multi-class model causes first of all dispersion of the flow: pedestrians will move away from high density areas in order to reduce their overall walking costs. Second of all, for the crossing flow and bi-directional flow cases, local route choice causes well known self-organised patterns to emerge (i.e. diagonal stripes and bi-directional lanes). We study under which demand conditions self-organisation occurs and fails, as well as what the impact is of the choices of the different model parameters. In particular, the differences in the weights reflecting the impact of the own and the other classes appear to have a very strong impact on the self-organisation process.

Modeling pedestrian behaviors under attracting incidents using cellular automata

Compared to vehicular flow, pedestrian flow is more complicated as it is free from the restriction of the lane and more flexible. Due to the lack of modeling pedestrian behaviors under attracting incidents (incidents which attract pedestrians around to gather), this paper proposes a new cellular automata model aiming to reproduce the behaviors induced by such attracting incidents. When attracting incidents occur, the proposed model will classify pedestrians around the incidents into three groups: the “unaffected” type, the “stopped” type and the “onlooking” type. The “unaffected” type represents the pedestrians who are not interested in the attracting incidents and its dynamics are the same as that under normal circumstances which are the main target in the previous works. The “stopped” type represents the pedestrians are somewhat interested in the attracting incidents, but unwilling to move close to the venues. Its dynamics are determined by “stopped” utility which can make the pedestrians stop for a while. The “onlooking” type represents the pedestrians who show strong interest in the attracting incidents and intend to move close to the venues to gain more information. The “onlooking” pedestrians will take a series of reactions to attracting incidents, such as approaching to the venues, stopping and watching the attracting incidents, leaving the venues, which have all been considered in the proposed model. The simulation results demonstrate that the proposed model can capture the macro-characteristics of pedestrian traffic flow under normal circumstances and possesses the fundamental characteristics of the pedestrian behaviors under attracting incidents around which a torus-shaped crowd is typically formed.

Quantification of the level of crowdedness for pedestrian movements

Within the realm of pedestrian research numerous measures have been proposed to estimate the level of crowdedness experienced by pedestrians. However, within the field of pedestrian traffic flow modelling there does not seem to be consensus on the question which of these measures performs best. This paper shows that the shape and scatter within the resulting fundamental diagrams differs a lot depending on the measure of crowdedness used. The main aim of the paper is to establish the advantages and disadvantages of the currently existing measures to quantify crowdedness in order to evaluate which measures provide both accurate and consistent results. The assessment is not only based on the theoretical differences, but also on the qualitative and quantitative differences between the resulting fundamental diagrams computed using the crowdedness measures on one and the same data set. The qualitative and quantitative functioning of the classical Grid-based measure is compared to with the X-T measure, an Exponentially Weighted Distance measure, and a Voronoi-Diagram measure. The consistency of relating these measures for crowdedness to the two macroscopic flow variables velocity and flow, the computational efficiency and the amount of scatter present within the fundamental diagrams produced by the implementation of the different measures are reviewed. It is found that the Voronoi-Diagram and X-T measure are the most efficient and consistent measures for crowdedness.

Continuum Theory for Pedestrian Traffic Flow: Local Route Choice Modelling and its Implications

This contribution puts forward a novel multi-class continuum model that captures some of the key dynamic features of pedestrian flows. It considers route choice behaviour on both the strategic (pre-trip) and tactical (en-route) level. To achieve this, we put forward a class-specific equilibrium direction relation of the pedestrians, which is governed by two parts: one part describing the global route choice, which is pre-determined based on the expectations of the pedestrians, and one part describing the local route choice, which is a density-gradient dependent term that reflects local adaptations based on prevailing flow conditions.Including the local route choice term in the multi-class model causes first of all dispersion of the flow: pedestrians will move away from high density areas in order to reduce their overall walking costs. Second of all, for the crossing flow and bi-directional flow cases, local route choice causes well known self-organised patterns to emerge (i.e. diagonal stripes and bi-directional lanes). We study under which demand conditions self-organisation occurs and fails, as well as what the impact is of the choices of the different model parameters. In particular, the differences in the weights reflecting the impact of the own and the other classes appear to have a very strong impact on the self-organisation process.

Performance Analysis of Simulation of Pedestrian Traffic inside the Hub

Transport hub belongs to the people highly gathering places,the pedestrian traffic within the hub is a nonlinear stochastic dynamic problem with uncertain cluster density. The computer dynamic simulation is one of the effective methods to investigate the dynamic characteristics of pedestrian traffic flow at present within the hub.The article studies the error between pedestrian traffic simulation of the commuter simulation software and the actual pedestrian traffic,and explains the simulation error due to the discrete space, fidelity are introduced to evaluate the accuracy of the simulation model.By comparing the Hohhot underground tunnel experimental data and simulation results and the analysis of pedestrian traffic characteristics, it is concluded that the pedestrian traffic simulation performance is closely related to the environment in the hub and the importance of the fidelity of simulation model.

Pedestrian signalization and the risk of pedestrian-motor vehicle collisions in Lima, Peru

Safe walking environments are essential for protecting pedestrians and promoting physical activity. In Peru, pedestrians comprise over three-quarters of road fatality victims. Pedestrian signalization plays an important role managing pedestrian and vehicle traffic and may help improve pedestrian safety. We examined the relationship between pedestrian-motor vehicle collisions and the presence of visible traffic signals, pedestrian signals, and signal timing to determine whether these countermeasures improved pedestrian safety. A matched case-control design was used where the units of study were crossing locations. We randomly sampled 97 control-matched collisions (weighted N=1134) at intersections occurring from October, 2010 to January, 2011 in Lima. Each case-control pair was matched on proximity, street classification, and number of lanes. Sites were visited between February, 2011 and September, 2011. Each analysis accounted for sampling weight and matching and was adjusted for vehicle and pedestrian traffic flow, crossing width, and mean vehicle speed. Collisions were more common where a phased pedestrian signal (green or red-light signal) was present compared to no signalization (odds ratio [OR] 8.88, 95% Confidence Interval [CI] 1.32–59.6). A longer pedestrian-specific signal duration was associated with collision risk (OR 5.31, 95% CI 1.02–9.60 per 15-s interval). Collisions occurred more commonly in the presence of any signalization visible to pedestrians or pedestrian-specific signalization, though these associations were not statistically significant. Signalization efforts were not associated with lower risk for pedestrians; rather, they were associated with an increased risk of pedestrian-vehicle collisions.

Exploring Areawide Dynamics of Pedestrian Crowds

The main objectives of this paper are to evaluate existing measurement methods of pedestrian traffic flow and to propose a three-dimensional approach that extends Edie's definitions of fundamental traffic variables to multidirectional walking areas by using three-dimensional pedestrian trajectories. Pedestrian crowds have an areawide fundamental diagram that is similar to a network fundamental diagram of vehicular traffic. Pedestrian traffic in a multidirectional area exhibits hysteretic behavior similar to that of some other many-particle physical systems. Some of the underlying dynamics of bidirectional pedestrian streams are explored with empirical data. Pedestrian streams behave somewhat differently from ordinary fluids with regard to the viscosity concept in the models based on fluid dynamics. The velocity profile for both unidirectional and bidirectional pedestrian streams is hyperbolic (with higher values on the boundaries and lower values in the middle), opposite that of fluids. The formation and dissipation of self-organized pedestrian lanes also are explored. A modification to Helbing's social force model is proposed with regard to the attractive force between pedestrians.

Improvement of pedestrian safety and traffic flow regulation at railway junction, Kandy

The junction near the Kandy railway station needs improvement as a solution to the traffic congestion at the location, especially during the peak hours of the day. The existing problem was studied in detail and several reasons for this problem were identified. To identify the movement of traffic and pedestrians at the railway junction, traffic studies were conducted during weekdays and weekends. Vehicular traffic by vehicle category, vehicle movements, and pedestrian traffic patterns were studied after identifying the three peak hours (morning, mid-day and evening) of the day. A heavy pedestrian movement surrounding the study locality was observed due to the presence of several main government institutions around that junction. Pedestrian traffic flow, pedestrian volumes and the level of service were calculated by the results collected from the pedestrian traffic surveys. A questionnaire survey was carried out during the peak hours to collect the views of the pedestrians about the existing situation at the location and the results were used in the analysis. As a measure to reduce the traffic congestion and improved vehicular flow and pedestrian safety, an underground pedestrian crossing structure together with an at-grade signalised scheme was proposed and designed. J.Natn.Sci.Foundation Sri Lanka 2013 41 (3): 259-270 DOI: http://dx.doi.org/10.4038/jnsfsr.v41i3.6060

Designing Bus Rapid Transit Facilities for Constrained Urban Arterials

Providing bus rapid transit (BRT) service on urban arterials can be a challenge for transportation agencies as they try to provide transit benefits within an existing street infrastructure. Projects must deliver high-quality transit service while supporting other needs, such as pedestrian activity, traffic flow, on-street parking, and crash safety. Transportation agencies must make trade-offs in designs to achieve a project's goals without miring the early project planning in costs and delays. This paper describes the selection by the New York City Department of Transportation and the Metropolitan Transportation Authority New York City Transit of the most appropriate on-street BRT running way design for Webster Avenue (US-1), a key north–south arterial in the central Bronx. The selection was based on a balanced, multimodal set of criteria. Three BRT running way alternatives—curbside, offset, and median bus lanes—were considered for Webster Avenue's 70-ft-wide right-of-way during the screening process. The four primary screening categories were transit operations, traffic operations, on-street parking and delivery curb space supply, and pedestrian benefits. Each design alternative was evaluated at two sample intersections that represented typical corridor conditions, and the results were expanded for a complete corridor evaluation. The evaluation found that the offset bus lane most effectively balanced the transit and traffic needs along the Webster Avenue corridor while maintaining on-street parking and supporting pedestrian activity; thus, it is the preferred corridor design.