Four-way Intersections Research Articles

Spatial Analysis of Kuwait Street Networks

Objective: Since only little is known about street networks (SNs) in developing countries, the overarching aim of this study is to spatially analyze Kuwait SN griddedness, transportation efficiency, and connectivity, using several indicators (i.e., orientation-order, street circuity, average street length, average node degree, proportion of dead-ends, and proportion of four-way intersections). Methodology: This work utilizes the python package OSMnx which obtains, models, and analyzes the open-sourced data repository OpenStreetMap to analyze the Kuwait built environment. This analysis has been complemented with qualitative information. Results: the key findings are: (I) orientation-order is lowest in some of the coastal areas and high in some modular residential areas; (II) Furthermore, compared to residential areas, non-residential areas have coarse-grained SNs, lower intersections connectivity and higher street circuity. Conclusion: Through acknowledging these features, more sustainable urban planning can be undertaken for expanding the built area in Kuwait. Further, the obtained data was made available for conducting further studies.

Vehicle Counting System and Smart Traffic Light Control System

Improving traffic flow efficiency has become more important due to the growing number of vehicles in urban areas, and this requires optimizing traffic control systems. In order to reduce traffic, a smart traffic control system using infrared sharp sensors to count vehicles at intersections is proposed in this paper. The system uses sensors to measure distances to a fixed barrier, accurately counting vehicles while ignoring pedestrians. It was originally designed for four-way intersections but is adaptable to various junction types. Each lane’s unique count is controlled by a separate Arduino Nano Board, and the data is saved in microcontrollers. Following the aggregation and processing of these counts, an Arduino Mega Board modifies the traffic light timings in response to actual vehicle flow.

Designing a Roundabout to Overcome Traffic Congestion at a Four-Armed Intersection

The growth rate of vehicles is increasing in most metropolitan areas, and as a result, traffic congestion is also increasing, particularly at intersections. Traffic congestion is one of the major problems faced by most of the developing countries despite the measures taken to mitigate and reduce it. In order to overcome traffic congestion, especially in four-way intersections with increasing growth rate of vehicles, roundabout design is a popular traffic management solution in urban areas. In most countries, roundabouts have been widely adopted as an alternative to signalized intersections due to their ease of operation with fewer conflict points. In a metropolitan city like Chennai, there are numerous areas facing traffic congestion. This study aims to design a roundabout for a four-armed intersection located at one of the most congested areas in Chennai, India - Porur Junction. It is a four-armed intersection with traffic on all approach roads and controlled by a signalized intersection. The effective solution would be an elevated roundabout bridge by connecting the major roads towards Poonamallee and Guindy with a two lane road and the minor roads towards Kundrathur and Arcot Road with two separate lanes, one for entering and the other for exiting the junction. The efficiency of the elevated roundabout bridge is that it has speed breakers in the entry ramp which slows down the vehicle & has a central island structure which is used to effectively manage the traffic without stopping the vehicles. After passing through the Central Island, vehicles can exit the barrier at a higher speed than the entry speed in a clockwise direction.

The Impact of Maturity on Role of Head and Eye on Ocular Motions to Intersection Scanning Conduct

Objectives: The Objectives of researchers of this study are to find out if there was a relationship between age and the input of head and hand actions on scanning conduct at crossings. Impending junctions necessitates scanning a broad region, which necessitates big lateral head turns and eye movements.
 Methodology: We selected 53 participants in two age sets: 27 older (14 females and 19 males; 62-82 years) and 25 youngers (11 females and 14 males; 23-42 years) with visual acuity that fulfilled MA driver's license standards (minimum 21/41 modified or unmodified). Randomized control data, as well as vehicle position, speed, and heading, and info regarding other programmed automobiles, remained gathered at a rate of 32 cycles per second (rpm). With the help of a six-camera remote digital authentication scheme operating at 60 Hz, data on head and eye movements were acquired. This research was conducted at People Medical College Hospital, Nawabshah from April 2020 to March 2021.
 Results: When driving in a simulator, 29 drivers over the age of 28 were monitored to see how their eyes and heads moved as they drove. It was determined that there were two types of scans for each of the city's 19 four-way intersections: eye-only scans (which contained only eye actions) and head-plus-eye scans (head and eye movements). Experienced drivers' head-eye scans (47.7% vs. 55%), as well as eye-only scans, were lower than expected (9.3 percent vs. 11.2 percent). In head-eye scans, skilled drivers showed the lower head and visual attention percentage compared to younger drivers. Among senior drivers, more eye-only scans (7 vs. 6) were performed, even though there were lesser head-eye scans (just 2). If you look at all-gaze scans, you won't see any ageing effects. According to our results, eye and head motions have a significant influence in development of cognitive deficits. Our findings show that eye and head motions both contribute to age-related impairments in intersection scanning, emphasizing the necessity of evaluating both eye and head movements.
 Conclusion: To evaluate head motions, and to highlight the necessity for training programmed for senior drivers this can emphasize before approaching the junction.

Effect of street network design on traffic congestion and traffic safety

We examine the effects of street network design on congestion levels and crash rates in neighborhoods across Utah's Wasatch Front. We employ propensity score matching to select pairwise neighborhood samples that have other similar characteristics but differ greatly in street network design. Our results show that denser and more connected neighborhoods have significantly lower congestion levels, but they do not have measurably lower (or higher) crash rates, presumably due to the prevalence of four-way intersections. This study can help guide data-driven decision making on street network design standards for many of the growing urban areas across the country and globe.

Head Scanning Behavior Predicts Hazard Detection Safety Before Entering an Intersection.

We conducted a driving simulator study to investigate scanning and hazard detection before entering an intersection. Insufficient scanning has been suggested as a factor contributing to intersection crashes. However, little is known about the relative importance of the head and eye movement components of that scanning in peripheral hazard detection. Eleven older (mean 67 years) and 18 younger (mean 27 years) current drivers drove in a simulator while their head and eye movements were tracked. They completed two city drives (42 intersections per drive) with motorcycle hazards appearing at 16 four-way intersections per drive. Older subjects missed more hazards (10.2% vs. 5.2%). Failing to make a scan with a substantial head movement was the primary reason for missed hazards. When hazards were detected, older drivers had longer RTs (2.6s vs. 2.3s), but drove more slowly; thus, safe response rates did not differ between the two groups (older 83%; younger 82%). Safe responses were associated with larger (28.8° vs. 20.6°) and more numerous (9.4 vs. 6.6) gaze scans. Scans containing a head movement were stronger predictors of safe responses than scans containing only eye movements. Our results highlight the importance of making large scans with a substantial head movement before entering an intersection. Eye-only scans played little role in detection and safe responses to peripheral hazards. Driver training programs should address the importance of making large scans with a substantial head movement before entering an intersection.

An Analysis of the Effects of Crash Factors and Precrash Actions on Side Impact Crashes at Unsignalized Intersections

Annually, side impact crashes contribute to a significant proportion of road fatalities. These crashes typically occur as a result of traffic violations at intersections. This study contributes to efforts in addressing side impact crashes at unsignalized intersections by performing a path analysis to unravel some behavioral trajectories through which these crashes occur. The study further investigated how these behavioral pathways influence the severity of the crashes. Crashes that occurred at unsignalized four-way intersections and T-junctions in Alabama were used for model estimations. Three precrash actions, failed to yield right-of-way at the stop sign, failed to yield right-of-way at a turn, and running stop sign, were considered. The model estimation results reveal that some of the crash factors were more associated with certain precrash factors but not others at either four-way intersections or T-junctions or both. It was observed that side impact crashes that occurred under daylight conditions at four-way intersections, for instance, were less likely to involve running a stop sign but more likely to involve failure to yield at the stop sign and failure to yield right-of-way at a turn, but under dark and unlit roadway conditions, the at-fault drivers were more likely to run a stop sign or fail to yield at a stop sign but less likely to be involved in failure to yield right-of-way at a turn. This approach to injury severity analysis uncovers complex underlying relationships between precrash actions, other contributing factors, and crash outcomes.

Analysis Performance Of Conventional Algorithm And HMS Algorithm For Four-Way Intersection With Modified Round Robin

Traffic jam is currently one of the main problems for densely populated cities like Jakarta, Indonesia. One problem that causes traffic jams in Jakarta is that the traffic lights are too fast, which causes many cars to not be able to pass the traffic lights. There are already many algorithms to overcome this problem and get the right time for traffic lights based on how many vehicles are waiting in line, such as the HMS Algorithm and Conventional Algorithm. This research objective is to compare which algorithm has better performance to find the right amount of time for traffic lights to reduce traffic jams at four-way intersections with modified Round Robin method. And the result shown that the HMS algorithm is very suitable to be used in any condition for large or little vehicles, while conventional algorithms are only suitable to use for vehicles in the one little lane or the vehicles in one lane with other lane direction in the same place of lane

The Effects of an In-vehicle Collision Warning System on Older Drivers' On-road Head Movements at Intersections.

With age might come a decline in crucial driving skills. The effect of a collision warning system (CWS) on older drivers' head movements behavior at intersections was examined.Methods: Twenty-six old-adults, between 55 and 64 years of age, and 16 Older drivers between 65 and 83 years of age, participated in the study. A CWS (Mobileye Inc.) and a front-back in-vehicle camera (IVC) were installed in each of the participants' own vehicles for 6 months. The CWS was utilized to identify unsafe events during naturalistic driving situations, and the IVC was used to capture head direction at intersections. The experimental design was conducted in three phases (baseline, intervention, and carryover), 2 months each. Unsafe events were recorded by the CWS during all phases of the study. In the second phase, the CWS feedback was activated to examine its effect on drivers' head movement' behavior at intersections.Results: Older drivers (65+) drove significantly more hours in total during the intervention phase (M = 79.1 h, SE = 10) than the baseline phase (M = 39.1 h, SE = 5.3) and the carryover phase (M = 37.7 h, SE = 5.4). The study revealed no significant differences between the head movements of older and old-adult drivers at intersections. For intersection on the left direction, a significant improvement in drivers' head movements' behavior was found at T-junctions, turns and four-way intersections from phase 1 to phase 3 (p < 0.01), however, two intersection types presented a decrease along the study phases. The head movements' behavior at roundabouts and merges was better at phase 1 compared to phase 3 (p < 0.01). There was no significant reduction of the mean number of CWS unsafe events across the study phases.Conclusions: The immediate feedback provided by the CWS was effective in terms of participants' head movements at certain intersections but was harmful in others. However, older drivers drove many more hours during the active feedback phase, implying that they trusted the system. Therefore, in the light of this complex picture, using the technological feedback with older drivers should be followed with an additional mediation or follow-up to ensure safety.

УСЛОВИЕ БЕЗАВАРИЙНОГО ДВИЖЕНИЯ АВТОМОБИЛЕЙ НА РЕГУЛИРУЕМЫХ ПЕРЕСЕЧЕНИЯХ

Introduction: Improving intersection capacity will not be possible without accounting for traffic safety. Purpose of the study: We aim to determine the prerequisite for accident-free traffic at signal-controlled intersections with turning traffic flows. Methods: In our study, we used the methods of observation, comparison, and mathematical analysis. Results: We have carried out a field observation of traffic intensity at signal-controlled intersections in the city of Yekaterinburg, focusing on vehicles that moved when the green light was on. We have also analyzed traffic flow moving in three directions in the same lanes. We have discovered that traffic accident likelihood is the highest (54%) at four-way intersections. Three-way intersections account for 44% of traffic accidents, while the remaining 2% of accidents occur at multi-way intersections. Furthermore, we have determined the additional factors that impact safety in turning traffic flows at intersections. Our study demonstrates that in order to ensure maximum intersection capacity, the duration of the traffic signal cycle must be adjusted with the minimum safe distance between vehicles in mind.

Different neighborhood walkability indexes for active commuting to school are necessary for urban and rural children and adolescents

BackgroundLiterature focusing on youth has reported limited evidence and non-conclusive associations between neighborhood walkability measures and active commuting to and from school (ACS). Moreover, there is a lack of studies evaluating both macro- and micro-scale environmental factors of the neighborhood when ACS is analyzed. Likewise, most studies on built environment attributes and ACS focus on urban areas, whereas there is a lack of studies analyzing rural residential locations. Moreover, the relationship between built environment attributes and ACS may differ in children and adolescents. Hence, this study aimed to develop walkability indexes in relation to ACS for urban and rural children and adolescents, including both macro- and micro-scale school-neighborhood factors.MethodsA cross-sectional study of 4593 participants from Spain with a mean age of 12.2 (SD 3.6) years was carried out. Macro-scale environmental factors were evaluated using geographic information system data, and micro-scale factors were measured using observational procedures. Socio-demographic characteristics and ACS were assessed with a questionnaire. Several linear regression models were conducted, including all the possible combinations of six or less built environment factors in order to find the best walkability index.ResultsAnalyses showed that intersection density, number of four-way intersections, and residential density were positively related to ACS in urban participants, but negatively in rural participants. In rural children, positive streetscape characteristics, number of regulated crossings, traffic calming features, traffic lanes, and parking street buffers were also negatively related to ACS. In urban participants, other different factors were positively related to ACS: number of regulated crossings, positive streetscape characteristics, or crossing quality. Land use mix acted as a positive predictor only in urban adolescents. Distance to the school was a negative predictor on all the walkability indexes. However, aesthetic and social characteristics were not included in any of the indexes.ConclusionsInterventions focusing on improving built environments to increase ACS behavior need to have a better understanding of the walkability components that are specifically relevant to urban or rural samples.

The effects of age on the contributions of head and eye movements to scanning behavior at intersections

The current study was aimed at evaluating the effects of age on the contributions of head and eye movements to scanning behavior at intersections. When approaching intersections, a wide area has to be scanned requiring large lateral head rotations as well as eye movements. Prior research suggests older drivers scan less extensively. However, due to the wide-ranging differences in methodologies and measures used in prior research, the extent to which age-related changes in eye or head movements contribute to these deficits is unclear. Eleven older (mean 67 years) and 18 younger (mean 27 years) current drivers drove in a simulator while their head and eye movements were tracked. Scans, analyzed for 15 four-way intersections in city drives, were split into two categories: eye-only (consisting only of eye movements) and head + eye (containing both head and eye movements). Older drivers made smaller head + eye scans than younger drivers (46.6° vs. 53°), as well as smaller eye-only scans (9.2° vs. 10.1°), resulting in overall smaller all-gaze scans. For head + eye scans, older drivers had both a smaller head and a smaller eye movement component. Older drivers made more eye-only scans than younger drivers (7 vs. 6) but fewer head + eye scans (2.1 vs. 2.7). This resulted in no age effects when considering all-gaze scans. Our results clarify the contributions of eye and head movements to age-related deficits in scanning at intersections, highlight the importance of analyzing both eye and head movements, and suggest the need for older driver training programs that emphasize the importance of making large scans before entering intersections.

Associations between the neighbourhood characteristics and body mass index, waist circumference, and waist-to-hip ratio: Findings from Alberta's Tomorrow Project.

This study estimated the associations between neighbourhood characteristics and self-reported body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) risk categories among Canadian men and women. Using data from the Alberta's Tomorrow Project (n=14,550), we estimated 3- and 4-way intersections, business destinations, population count, and normalized difference vegetation index (NDVI) within a 400m radius of participant's home. Intersections, business destinations, and population count (z-scores) were summed to create a walkability score. Four-way intersections and walkability were negatively associated with overweight and obesity. Walkability was negatively associated with obesity. NDVI was negatively associated with high-risk WHR and population count and walkability positively associated with high-risk WHR. Among men, population count and walkability were negatively associated with obesity, and business destinations and walkability were negatively associated with overweight and obesity. Among women, NDVI was negatively associated with overweight (including obesity), obesity, and high-risk WC. Interventions promoting healthy weight could incorporate strategies that take into consideration local built environment characteristics.

Urban spatial order: street network orientation, configuration, and entropy

Street networks may be planned according to clear organizing principles or they may evolve organically through accretion, but their configurations and orientations help define a city’s spatial logic and order. Measures of entropy reveal a city’s streets’ order and disorder. Past studies have explored individual cases of orientation and entropy, but little is known about broader patterns and trends worldwide. This study examines street network orientation, configuration, and entropy in 100 cities around the world using OpenStreetMap data and OSMnx. It measures the entropy of street bearings in weighted and unweighted network models, along with each city’s typical street segment length, average circuity, average node degree, and the network’s proportions of four-way intersections and dead-ends. It also develops a new indicator of orientation-order that quantifies how a city’s street network follows the geometric ordering logic of a single grid. A cluster analysis is performed to explore similarities and differences among these study sites in multiple dimensions. Significant statistical relationships exist between city orientation-order and other indicators of spatial order, including street circuity and measures of connectedness. On average, US/Canadian study sites are far more grid-like than those elsewhere, exhibiting less entropy and circuity. These indicators, taken in concert, help reveal the extent and nuance of the grid. These methods demonstrate automatic, scalable, reproducible tools to empirically measure and visualize city spatial order, illustrating complex urban transportation system patterns and configurations around the world.

A Pedestrian Exposure Model for the California State Highway System

For this study, we developed one of the first statewide pedestrian exposure models, using log-linear regression to estimate annual pedestrian crossing volumes at intersections on the California State Highway System. We compiled a database of more than 1,200 count locations, one of the largest ever used to create a pedestrian volume mode. We initially evaluated 75 explanatory variables for the model. The final model is based on the three land-use variables (employment density, population density, number of schools), four roadway network variables (number of street segments, intersections with principal arterial and minor arterial roadways, and four-way intersections), and the U.S. Census Bureau’s American Community Survey journey-to-work walk mode share that are readily available or fairly easy to create using basic geographic information system analysis. The resulting pedestrian volume model was used to estimate annual crossing volumes at more than 12,000 intersections along the California State Highway System. This is one of the first statewide pedestrian volume models, and California may represent the largest jurisdiction to date to adopt a single, system-wide pedestrian volume model.

The emergence of macroscopic interactions between intersecting pedestrian streams

The interactions between individual pedestrians can lead to emergent effects, such as the formation of lanes in bidirectional flows. Here, we expose properties of an emergent effect at a macroscopic level, namely interactions between pedestrian streams that arise when pedestrians walk into and through four-way intersections from different directions. We propose non-spatial models for the number of pedestrians from different streams inside an intersection. Each model encodes a different hypothesis for how streams interact and can produce dynamics fundamentally distinct from the other models. By fitting our models to large experimental data sets and determining which model explains the data best, we determine when and how entire streams of pedestrians start to interact. We find that as arrival rates increase, streams start to interact and compete for space. Our results suggest that these interactions result in an even balance of pedestrian numbers across two orthogonally intersecting streams. Neither of the streams can dominate. In contrast, for four intersecting streams, our findings suggest that jams in some streams can coincide with higher flow rates in other streams and that the relative dominance of streams can switch stochastically. By adapting existing methodology, we thus present a coherent conceptual approach for investigating emergent effects in temporal dynamics at aggregated levels in pedestrian flows that could be applied to other scenarios. Our approach is flexible and uses easily measured quantities, making it highly suitable for observational data in different scenarios or deployment in applications.

Estimation of geometric route distance from its topological distance: application to narrow road networks in Tokyo

The structure of road networks has been investigated in accordance with the development of GIScience. By classifying road networks into wide and narrow ones, we can define the route as the path from the route’s origin (also called the root) on a wide road network to a narrow road segment which consists of the sequence of narrow road segments arranged by ascending order of the number of steps of adjacency to its root. The length of the route can be defined with the following geometric and topological terms: the route distance, measuring the length along the route and the depth, counting the number of road segments on the route. The depth plays the important role of being a substitute for the route distance in modelling road networks as a planar graph. Since road networks clearly exhibit irregular patterns and road segment lengths are non-uniform, it is considered appropriate to adopt a stochastic approach rather than a deterministic one to analyse the route distance. However, the relationship between the route distance and its depth has not been sufficiently investigated stochastically. Therefore, the research question is how can we estimate the route distance from its depth? Based on an empirical study in the Tokyo metropolitan region, it was found that (1) the statistical distribution of the route distance can be formulated as an Erlang distribution whose parameters are its depth and the inverse of the mean length of narrow road segments, and (2) this length is constant and close to 40 m. Therefore, we can estimate the route distance from only one parameter, the depth. Also, as a practical application, accessibility to the kth depth link in terms of firefighting was evaluated because the maximum length of the extension of fire hoses is approximately 200 m. It was found that (1) even if k ≤ 5, the probability that the route distance to the kth depth link is equal to or longer than 200 m ranges from 0 to 0.45; and (2) if k ≥ 8, the probability is approximately 1. These indicate the limitation of the deterministic approach because, on the basis of complete grid patterns (with intervals of 40 m between intersections), k = 5 corresponds to a distance of 200 m from wide road networks and the route to the 5th depth link can be covered with fire hoses. Moreover, it was found that the connectivity of wide road networks is higher than that of narrow ones in terms of the smaller ratio of cul-de-sacs and the larger ratio of four-way intersections. These answers contribute substantially not only to constructing a science of cities that provides a simple model and specifies the most important parameter, but also to our understanding of the structure of narrow road networks within several hundred metres of wide road networks.

Towards computer vision-based approach for an adaptive traffic control system

ABSTRACTIn this paper, an adaptive traffic control system (ATCS) is proposed using the state of the art of video processing techniques. We illustrate how the system controls standard four-way intersections using three parameters; namely, average vehicles flow speed, level of crowdedness of vehicles, and a critical state timer. These parameters are detected from traffic videos using our computer vision algorithm. The ATCS decision-making process has been designed to adapt to predefined priorities over the traffic parameters. The validation of the proposed ATCS has been tested using four synchronized test videos in order to feed the proposed ATCS with different traffic information. Experimental results show a complete adaptation for the traffic flow.

Trip and parking generation rates for different housing types: Effects of compact development

Guidelines for trip and parking generation in the United States come mainly from the Institute of Transportation Engineers (ITE). However, their trip and parking manuals focus on suburban locations with limited transit and pedestrian access. This study aims to determine how many fewer vehicle trips are generated and how much less parking demand is generated, by different housing types (single-family attached, single-family detached, and apartment and condo) and in different settings (from low density suburban environments to compact, mixed-use urban environments). Using household travel survey data from 30 diverse regions of the United States, we estimate a multilevel negative binomial model of vehicle trip generation and a multilevel Poisson model of vehicle ownership, vehicle trip generation and vehicle ownership being logically modelled as count variables. The models have the expected signs on their coefficients and have respectable explanatory power. Vehicle trip generation and vehicle ownership (and hence parking demand) decrease with the compactness of neighbourhood development, measured with a principal component that depends on activity density, land use diversity, percentage of four-way intersections, transit stop density and employment accessibility (after controlling for sociodemographic variables). The models capture the phenomena of ‘trip degeneration’ and ‘car shedding’ as development patterns become more compact. Reducing the number of required parking spaces, and vehicle trips for which mitigation is required, creates the potential for significant savings when developing urban projects. Guidelines are provided for using study results in transportation planning.

Spatial navigation from same and different directions: The role of executive functions, memory and attention in adults with autism spectrum disorder.

Navigating an environment is difficult for people with ASD independent of whether they are travelling in the same or in a different direction from that which they originally studied. The present study suggests that flexibility in alternating travel directions, difficulties in remembering landmarks as well as reduced attention to landmarks while learning a route play a role in the navigation difficulties in ASD. Guidance at route learning might help autistic individuals to improve their ability to navigate in their environments.