Assessment of Traffic Delay Problems and Characteristics at Urban Road Intersections: A Case Study of Ilorin, Nigeria.

Transportation has been of immense benefits to the social, economic and political development of communities, however, it is sometimes characterised with negative impacts such as traffic congestions, delays, environmental pollutions and crashes. In this study, the level of service of selected major road intersections in Ibadan were investigated. Traffic volume of each intersection approach was conducted from 7am - 7pm on Mondays, Wednesdays and Saturdays, delay studies were carried out during the morning, afternoon and evening peak hours and level of service for each approach was determined from the average delay per vehicle. The traffic volume reveals that passenger cars are the predominant vehicles at all the approaches and the morning and afternoon peak hours occurred between 8 to 9am and 2 to 3pm, respectively. The level of service for all the approaches is B, indicating slight reduction in capacity of the intersections. Keywords: Transport, Traffic volume, Traffic delay, Traffic congestion and Road intersection DOI : 10.7176/JIEA/9-7-05 Publication date: December 31 st 2019

The paper examines a roundabout located in a residential district of Lviv city. The area has many attraction points, so traffic and pedestrian flow volumes are large. All approaches to the roundabout have unsignalized pedestrian crosswalks, three of which lack safety islands. Field studies were conducted on peak and off-peak periods, collecting primary indicators of traffic and pedestrian flows. Traffic flow delays were determined on the approaches to the roundabout under existing traffic conditions with the help of the PTV VISSIM software. Three options were proposed for arranging pedestrian crosswalks on approaches to the roundabout. The first option was an arrangement of safety islands on all pedestrian crosswalks. The second option was an arrangement of underground pedestrian crosswalks. The third option was the implementation of adapting traffic light control with a call button for pedestrians. Traffic simulation was carried out for all three proposed options with the finding of the delay per vehicle and the values of the average and maximum length of the queue of vehicles on the approaches to the roundabout. All three options showed better results of traffic delay than existing conditions. However, there were delays caused by the traffic flow itself. These delays are seen in the results of the simulation of option two. Traffic delays are the smallest at this option. Option one showed the highest values of traffic delays in comparison with the other two options. The advantages and disadvantages of each option for arranging pedestrian crosswalks are determined. Recommendations are given regarding the feasibility of locating various types of pedestrian crosswalks on the approaches to the roundabout. Given the research results, the best option from the view of traffic and pedestrian flows, their delays and safety is the third one.

Problem. The conducted analysis showed that parking along city streets in central areas often complicates the movement of public transport and specialized vehicles. Parked cars reduce the capacity of the road network by 20-40%, which slows down traffic and increases the likelihood of accidents. With the increase in the number of cars in Ukraine, the issue of organizing parking spaces is becoming increasingly acute, as the growth in the number of cars complicates the arrangement of new parking areas.In order to increase the efficiency of the transport network, it is necessary to implement new organizational measures that will contribute to increasing the capacity of the street-road network in places with active parking. Special attention should be focused on intersections, where parking limits visibility and reduces traffic intensity. Areas where entry and exit from parking lots are also important.The purpose of the research is to model the impact of street parking on traffic flow delays in the area between intersections.Research methods. The use of street parking lots plays an important role in solving the problem of car parking in cities. However, their main drawback is the negative impact on the capacity of the road network. Therefore, the key criterion for evaluating this type of parking is determining its impact on throughput.Capacity is affected by many factors: road conditions, composition of traffic flow, weather conditions, psychophysiological characteristics of drivers, etc. Changing these parameters can significantly influence throughput at different times of the day, month, season, or year.Estimating the impact of street parking on the capacity of the road network requires an approach that takes into account different patterns of car placement on the roadway. The decrease in throughput is caused by a decrease in the speed of traffic flow, which is an important characteristic of traffic and significantly affects the efficiency of using the street network.To model the impact of street parking on traffic delays, it is necessary to take into account such parameters as the time and frequency of the arrival of cars, the duration of their parking, the length of the queue, and the capacity of the parking lot. It is also important to pay attention to the cost of parking, information about the occupancy of the parking lot, and public transport routes. Since most of these parameters are random, simulation modeling is an effective tool for prediction.The main results of the study. Areas of the central part of Lviv with heavy traffic were chosen for the study, where cars are parked in different ways near the roadway. The analysis was carried out using the PTV Vissim software environment. The reasons affecting the speed of traffic and the capacity of the streets due to the presence of parking have been studied. A simulation model was created that made it possible to evaluate the operation of areas with and without permitted parking, as well as the impact of parking duration on the average flow speed and delay. The results showed that to increase the capacity and speed of transport when designing parallel street parking lots, it is necessary to set limits on the duration of parking. The average traffic delay is the lowest for parking durations of 900 s and 1800 s, being 6.34 and 6.45 s/car, respectively. This indicates that with a longer parking time, drivers have more opportunities to exit without obstruction, which helps to reduce delays in the traffic flow. The biggest delay is observed with a parking duration of 300 s in the right lane, where it reaches 9.43 s/car. This is probably due to the frequent stops of cars, giving way to those leaving the parking lot. Such delays can increase the total travel time on a certain section of the road, which negatively affects the efficiency of traffic flow and creates additional inconvenience for drivers. Taking these indicators into account is important when planning parking zones to optimize traffic and reduce delays.Conclusions and specific proposals of the authors. The results of modeling the impact of on-street parking on traffic flow delays, carried out using the PTV VISSIM software, show that when designing on-street parking parallel to the pavement, it is advisable to set limits on the duration of parking. This will help to increase the capacity of the road network and increase the average speed of vehicles. The establishment of such restrictions will also minimize traffic delays, which will positively affect the overall efficiency of traffic flow and reduce the level of congestion, especially during peak hours.

Urban road intersections are a major factor that influences the effectiveness of traffic flow systems.This paper is aimed at examining the performance of road intersections in the Lagos metropolitan area using the "Y-junction" of Oga-Ikorodu (Lagos, Nigeria) as the case study.The study examines the delay factors, time wastage and traffic conflicts.The study uses a reconnaissance survey, delay analytical tool, vehicle spot speed study and traffic volume survey to assess the level of delay, economic loss and traffic flow interruption.The study reveals that there are varying Levels of Service (LOS) obtainable at different times of the day on different carriageways, while Ayangburen Road records the best LOS of B in the morning, the afternoon and evening recorded C and D respectively.A different scenario holds for both Lagos and Sagamu as they record the worse LOS of E in the evening peak.In a related manner, the percentage of vehicle stoppage falls between 41.1%-87.8%indicating that vehicles tend to experience a stop scenario than not-stop at each approach especially during the peaks.It is therefore pertinent to note that the road intersection operates at a very low level of service especially during the evening peak when controlled by traffic wardens.It is therefore recommended that a Diamond-at-grade intersection be constructed in the area instead of the round-a-bout.The introduction of an automated traffic control system with full control of access and total removal of on-street parking will remove the road users' burden in that area.

This study explores the practical utilization of open data to analyze and improve urban transportation systems, focusing on leveraging real-time Google Traffic maps (GTM) data for automatic extraction of road traffic delay patterns. The research began by defining the study area geographically for data extraction from open street maps. A specialized extraction procedure, executed via the "r.tikrit" R code deployed on a server, tailored extraction intervals considering server constraints and area dimensions. The resulting traffic delay values were transformed into a spatial object table, enabling Geographic Information System (GIS) data analysis and visualization. The dataset, stored as daily tabular records, with hourly data input, accompanied by contextual raster images, facilitated comprehensive analysis.  The methodological framework comprises three primary phases: firstly, defining the study area and segmenting roads; secondly, setting up the r.tikrit code; and thirdly, conducting data analysis and extracting traffic flow patterns. Throughout the developmental phases, Generative AI tools played a pivotal role as assistants, aiding in the development of analysis codes, streamlining the extraction process, and facilitating the literature survey. Subsequent research phases involved testing multiple applications: 1)Traffic Flow and Commuting Delay: Calculating traffic delay, peak hours and roads congestion situation 2) Spatial-Temporal Semi-Stationary Traffic Flow: Identifying unusual delays in selected roads segments that might be linked to external factors like accidents or natural hazards. 3) Traffic Flow Delay - Rainfall Relationship: Evaluating the impact of rainfall events on traffic networks and traffic delay. The approach's strength lies in its ability to generate high-resolution spatial and temporal road traffic delay data continuously. However, acknowledging inherent limitations of Google Traffic maps—such as inactive roads and discrepancies with open street maps—is vital. Despite these limitations, This methodology serves as an indispensable tool for researchers aiming to gain comprehensive insights into the complex status of urban traffic congestion patterns. Furthermore, it facilitates extended research into understanding the correlations between urban traffic and the ambient environment, enabling a deeper exploration of their impacts.

Traffic congestion has been identified as a significant contributor to the environmental degradation and elevated fuel consumption. The causes of traffic delays are multifaceted, with toll booths positioned on highways being a notable factor. This study aims to analyze the impact of toll booths on traffic congestion, with a particular focus on the case study of the highway toll booth in question. The analysis will include a comparison of the delay times before and after the implementation of the FASTag system. The study will also undertake an economic evaluation to assess the cost implications of delay. The findings of this study indicate that congestion is more pronounced in the presence of manual toll booths compared to automated systems. The present study uses the 'Chakiya Toll Plaza on National Highway 27A, located between Motihari and Muzaffarpur, as a case study. This toll booth has been initially operated with a manual toll collection system, but has since transitioned to the FASTag implementation. A comprehensive analysis encompasses both traffic volume and delay studies, with a focus on their environmental and economic ramifications. The analysis reveals that for each Passenger Car Unit (PCU), the environmental cost is 8.3 rupees and the fuel cost is 15.34 rupees. The idle time cost is calculated as 8.34 rupees. The overall cost of the manual toll collection delay, including all the aforementioned factors, is found to be 52.3 rupees. However, the implementation of FASTag significantly reduces this cost to. 8.20 rupees.

Traffic delay modeling has been an interesting area of research and plenty of work is presented for delay estimation. Traffic delay is the severe problem in developing countries as well as in developed countries, caused by traffic congestion. Several factors (traffic volume, green time, weather conditions, road conditions, visibility) influenced the delays hence must be considered while estimating the delay. Prediction of traffic delay is an essential task for optimization of traffic flow on the road network. In this paper, traffic delay is predicted using Artificial Neural Networks (AANs) approach as it is one of the best methods for modeling and prediction. The results exhibit that the proposed methods may be used as a propitious approach in traffic delay prediction.

In this paper, based on traffic flow characteristics of urban highways and discreteness 才 theory of numerical analysis, a series of traffic models including traffic generation model, car-following model, and lane changing models were built to study microscopic traffic flow simulation and calculation methods of urban road signal controlled intersections. Then a numerical simulation C++ program was coded on Linux platform using discrete mesh method after determining a reasonable traffic flow simulation parameters, and simulation results were verified using traffic survey data analysis. Finally, the basis for how to optimize urban road intersections congestion state and how to make decisions about traffic management and control of signalized intersections were provided, and the optimized way The urban transport system is composed of pedestrian, vehicles, roads, environment, and other factors. It is a dynamic system and it has complex structure, with multiple influencing factors, randomness, and unstable factors. In recent years, with the improvement of people's living standards, the urban vehicles and resident trips have been increased. This led to serious urban traffic congestion, dropped traffic speed, increased traffic accident rate, and environmental pollution. It has become a bottleneck that restricts the development of the urban economy. The intersections are the joints of the urban road network, and the study of the road intersection is the key to solve the traffic problems in the city. The actual capacity of intersection and vehicle delay time are an important indicator of the evaluating operation efficiency and service level of the intersection (1). In this paper, firstly, the intersection layout model, traffic generation and operation model, and signal control model were built to analyze the actual situation of the intersection and traffic characteristics. Then, based on these models, an urban road intersections traffic flow simulation program was developed and conducted with numerical simulation. Finally, the simulation model and modeling platform were verified by using a large number of field survey data. 2. Traffic Flow Modeling In this paper, traffic flow discrete model is considered in the fully discrete ideas of cellular automata and classic GM model (2) at the same time. Its basic idea is the road network will be divided into a number of square grids with the same size, length, and width of each grid representing certain distances. Roads are composed of several grids that merge together according to certain rules. The different grid cell represents a different size of vehicle. Grid length is defined as average space headway when blocked. The speed unit is m/s, the time step in this study is 1 second. CICTP 2015

Introduction. Many studies have argued that traffic delays at unregulated intersections depend on the intensity of the main flow and the intensity of pedestrian flow. Purpose. It is proposed to investigate traffic flow delays using the VISSIM software environment at unsignalized intersections at different flow rates. Results. Areas of the street and road network for experimental research were selected in the central part of Lviv. Triangles of visibility distance are calculated, problem places where it is necessary to establish a road sign 3.29 “Limitation of the maximum speed of movement” are defined. An analysis of existing methods for determining traffic delays at unregulated intersections is carried out at the paper. The method of estimating the average speed of traffic flow and the method of simulation modeling of transport flows in order to build a theoretical model are presented. The analysis of the dependence of the change of transport delays, obtained based on measured actual data and the method of modelling traffic flows, is carried out. The visibility distance for each intersection is calculated taking into account the speed mode. Graphical dependences of the change of the average and maximum length of the queue of vehicles under different modes of traffic light regulation in the secondary direction are given. It is determined that the average flow speed varies from 17 km/h to 38 km/h when changing the maximum speed limit from 15 km/h to 40 km/h. It is established that the lowest average traffic delay at unregulated intersections is observed at a traffic flow speed of 30 km/h. Conclusions. The substantiation of the introduction of the recommended speed regime on sections of streets with limited speed is given which takes into account transport delay, queue length, geometric parameters of the street, the presence of public transport stops and pedestrian crossings, traffic intensity and composition. The proposed method of controlling secondary traffic flows at unsignalized intersections, allows to increase traffic safety when traveling in secondary vehicles.

Traffic delay in arterial road is an important criterion in the judgment of service level of transportation. At present, there exist a certain degree of congestion problems in most road intersections, especially in the holidays. In order to assess and predict the degree of congestion in road intersection, the traffic simulation research of a chosen area in Jinshan road was undertaken. PTV VISSIM was used to generate the simulated traffic flow data. Linear Regression model, SoftMax and machine learning were combined to process the simulated data generated from VISSIM micro simulation. This is in the aim of building a proper model that can be used for data generation like predicted transport traffic delay as well as predicted degree of congestion under ranged traffic volumes. This research may act as a guidance and reference for city designers and transportation engineers in their further research about Jinshan Road as well as others.

This study was designed to establish the current demographic and treatment patterns of mandibular fractures in two urban centers (Lagos University Teaching Hospital, Lagos, and National Hospital, Abuja) in Nigeria. All cases of mandibular fractures diagnosed and treated at the Department of Oral and Maxillofacial Surgery, Lagos University Teaching Hospital, Lagos (1998-2007) and Department of Oral and Maxillofacial Surgery, National Hospital, Abuja, Nigeria (2001-2007) were reviewed. Data collected included age, sex, etiology of fracture, anatomic site of fracture, associated maxillofacial fracture, types of treatment, and postoperative complications. The highest incidence of mandibular fractures (49.3%) occurred in the age group 21-30 years and the lowest in the age group 0-10 years, with male preponderance in nearly all age groups. Road traffic crashes (RTC) were the leading cause (67.5%), followed by assault (18.8%), and gunshot. Of the RTC cases, 85 (40%) were sustained from motorcycle-related crashes. The commonest site of fracture was the body of the mandible (n = 137), followed by the angle (n = 114). The majority (83.1%) were treated by closed reduction using intermaxillary fixation, 13.1% by open reduction and internal fixation, and 3.8% had conservative treatment. Mandibular fractures are commonest during the third decade of life and in men, with almost half of the cases due to of road traffic crashes. RTC was the leading cause of mandibular fractures in all age groups. Motorcycle-related mandibular fractures seem to be increasing in Nigeria. There is a need to enforce legislation designed to prevent RTC to reduce maxillofacial fractures in Nigeria.

In recent years, most traffic accidents and congestions usually occur at road intersections in urban areas where the vehicle speed is high. This has necessitated the need for intelligent road transport systems and high-level algorithms to unravel the problem. In this study, the South Africa Road transportation system has been used as a case study to address traffic flow solutions at signalized road intersections using traffic flow variables such as traffic density, speed of vehicles, and traffic volume as decision variables. This paper focuses on using a hybrid creative algorithm based on signalized traffic flow to address the constant repetitive traffic congestion problem. The proposed hybrid algorithm is the adaptive neuro-fuzzy inference system (ANFIS). The speed of vehicles within the investigation period, the traffic density of the road network, and the traffic volume of vehicles on the road were used as input and output variables, respectively. Triangular membership function and Gaussian membership function were used for input and output variables, and rules were developed based on available traffic flow parameters. The result of the ANFIS model showed a training and testing performance of 0.8722 and 0.9370, respectively. This training and testing results showed that the ANFIS model is an effective model for optimizing traffic flow at signalized road intersections.

Traffic delay is causing loss of valuable time to the general commuter and restricts the road network from functioning in an orderly manner. Researchers have concluded that millions of dollars worth of business is lost due to delay caused by road congestion, and consequently hindrance or abolishment of important business undertakings. In this research, we present a hybrid system that calculates link delay between road intersections using fuzzy logic. The aim of the system is to compute a near optimum path using the soft computing techniques such as breadth first search (BFS), depth first search (DFS) and genetic algorithms (GA). The outcomes of this study indicate that the hybrid system solves the traffic routing problem much more efficiently than the existing stand-alone techniques. The results of this research can be integrated with a traffic advisory system, which can alert a user for optimum route selection or inform civil authorities about possible traffic bottlenecks.

The growth of the car fleet and the increase in traffic is accompanied by an increase in traffic, and in conditions of cities with historically formed buildings leads to traffic problems. It is especially evident on the sections of the road network with a large number of intersections on the motorways. They are characterized by an increase in traffic delays, queues and congestion formation, a decrease in communication speed, an increase in fuel consumption, increased triggering of vehicles. In addition, the environmental condition of the sections of the motorways is deteriorating. With the increase in the number of cars, the negative features of motorization are manifesting themselves, namely, a significant decrease in the speed of traffic flows on the road network due to traffic delays. Traffic delays and congestion are affected by a number of factors: the width of the roadway, the mode of traffic lights, the presence of parked cars along the edges of the roadway, the geographical location of the streets, traffic accidents, the driver’s psychological status, level of professional training, etc. The constant increase in the number of vehicles on city highways leads to periodic congestion of the road network. Congestion can be considered as a negative factor of active motorization in conditions of shortage of road space. Traffic congestion, like any traffic delays, leads to economic losses: the cost of time, the decrease in the efficiency of freight traffic, the increase of fuel costs, the increase in the number of accidents. Studies of traffic conditions were conducted on the street Pushkinskaya, which is classified as one of the main streets of city value. The formation of traffic flows on the main street is caused by the merger of flows from the crossroads and adjacent streets. Movement of traffic flows down the street is in the direction both to the central part of the city and in the opposite direction. This section creates difficult traffic conditions that are highly dependent on the large number of vehicles parked along the roadway. The location of parked vehicles with different dimensions reduces the width of the roadway, which significantly affects the speed of traffic, traffic capacity and traffic safety.

This paper presents a quantitative analysis model of curb parking impacts on traffic flow delay. Whether a road is appropriate setting curb parking is quantitatively analyzed. Based on the variation of traffic delay on a road with curb parking lots, the impacts of curb parking facilities on traffic flow are analyzed. The traffic delay caused by curb parking activities that under both low and high volume conditions are researched. A model respectively using discrete, continuous values of delay as evaluation indicator is built. The validity of the model is tested through application examples.