Exit Lane Research Articles

Intersection optimisation study based on traffic conditions in the physical area

The contemporary prevalence of car ownership has presented urban intersections with burgeoning challenges in terms of motorisation and congestion. Traditional signal timing schemes often encounter difficulties in handling the resulting vehicle conflicts within the physical area of the intersection. Accordingly, an intersection traffic signal timing method based on the intersection physical zone traffic status (IPAT-ATS) is proposed in this study. Different types of intersection anomalies are defined based on the impact of various abnormal vehicle operating states on vehicle flow in each entrance and exit lane. Using a traffic efficiency model, the flow state of intersections under different abnormal states is analysed to allocate traffic flows optimally, thereby maximising traffic efficiency under various abnormal states. The proposed method undergoes testing through simulations at the Weidi Road and Youyi Road intersection in Tianjin, China. Compared with the current signal timing scheme, this method significantly enhances the intersection efficiency for different traffic anomalies.

Modeling of Vehicle Left-Turn Trajectories and Exit Lane Selection at Signalized Intersections

Modeling of Vehicle Left-Turn Trajectories and Exit Lane Selection at Signalized Intersections

Evaluation of Different Work Zone Road-Occupation Schemes for Monorail Construction

Due to the increasing demand for transportation, road renovation is inevitable, and the emergence of work zones has become the most common problem in traffic control. There are many research results on the impact of work zones on traffic operation, but most of them focus on various capacity theoretical models or traffic flow control strategies and are mostly concentrated in highway work areas and urban road subway construction work areas. The location of these work zones is often unable to be changed and is mostly considered reasonable. At present, there is still a gap in selecting and evaluating the location of the work zone. Therefore, this article studied a bidirectional six-lane intersection in Xi’an and investigated the situation of traffic flow distortion caused by the setting of work zones at the intersection. Two different positions and forms of work zones were designed for evaluation and analysis. Firstly, we used VISSIM (2022 student) to simulate the original and proposed work zone road-occupation schemes and analyzed six indicators. Finally, in order to determine the optimal work zone locations under different traffic situations, we applied the entropy weight method (EWM) to assign weights to multiple indicators, thereby achieving a comprehensive assessment of various schemes. The results showed that the highest improvement level among the six indicators was 50.2%, and different schemes adapted to different traffic situations. However, occupying two lanes of the median opposite the exit lane performed better under high traffic volume. Occupying the median and lanes on both sides of the median is suitable for low traffic volume. Occupying two lanes of the entrance lane and using the opposite lane as the left-turn entrance lane is suitable for situations with high traffic volume in the opposite lane.

Assessing the risky riding behavior and the effect of entrance behavior of right-turning motorcyclists on critical gap at T-junctions

T-junctions have a high risk of traffic crashes, and motorcyclists tend to behave differently at different types of junctions. This study aims to determine the motorcyclists’ risky riding behavior and to investigate the effect of risky right-turning behavior of motorcyclists on the critical gap at three types of T-junctions: type A (conventional T-junction), type B (unconventional T-junction with a short exit lane for right-turning minor road vehicles) and type C (unconventional T-junction with short exit lane for through major road vehicles). Eight risky riding behaviors identified are “riding a motorcycle without wearing a helmet”, “no signal when turning”, “not switching on the headlight during daytime”, “riding on the opposite or wrong side of the road”, “crossing a junction without fully stopping”, “riding or performing a turn that is not according to the right of rule”, “stop after the stop line” and “playing mobile phone”. Type A junction has the highest percentage of motorcyclists with risky riding behavior. Using Raff's method, the critical gap for type A was 9.20 s, 7.00 s for type B, and 7.20 s for type C. The follow-up times for type A, B, and C T-junctions were 3.32, 2.50, and 2.63 seconds, respectively. Type B T-junction provides the best performance for a motorcycle to turn right from the minor road as it has the smallest critical gap and follow-up time. The exclusive short exit lane for minor-road right-turning vehicles on the major road effectively made drivers and motorcyclists feel safer and confident.

Autonomous Intersection Management for Connected and Automated Vehicles: A Lane-Based Method

Most existing studies on autonomous intersection management (AIM) often focus on algorithms to accommodate conflicts among vehicles by assuming that the entrance lane and the exit lane of vehicles are exogenous inputs. This paper shows that allowing entrance lanes and exit lanes to be optimized can significantly improve traffic efficiency. In particular, this paper proposes “all-direction” lanes, where left-turn, through, and right-turn traffic is all allowed at the same lane. We develop two methods for optimizing entering time (i.e., when to enter the intersection) and route choice decisions (i.e., entrance lane and exit lane), including the sliding-time-window-based global optimum (GO-STW) and the first-come-first-served method with optimal route choices (FCFS-R). The developed lane-based methods can be formulated as mixed integer linear programming (MILP) problems, which can be solved using the CPLEX solver. A heuristic is further adopted to solve the MILP model in a timely manner, which illustrates the potential real-time applicability of the proposed method. Numerical analysis is conducted to examine performance and effectiveness of the proposed methods and heuristic. We found that the optimization of lane/route choices is often more critical than entering time.

A method to estimate urban work zone intersection capacity under multiple influencing factors

Work zones generate significant congestion in urban centers, yet the influence of various capacity factors in urban arterials and intersections are poorly understood. This paper analyzes the influence of the following factors on urban arterial and intersection work zone capacity from 22 intersections: heavy vehicle flow, heavy vehicle percentage, work zone length, maximum speed limit, entrance lane width, left turn volumes, entrance and exit lane width reductions, and intersection length and width. An urban work zone was modeled using VISSIM simulation software, and regression models were developed based on the reduction coefficients with MATLAB software for fitting analysis. The results show that the proposed model estimated work zone capacity with high accuracy. Urban work zones were found to reduce capacity by 64% in the selected arterial and by 35% in the selected intersection, with corresponding increases in delay and queue length. The model also estimates the capacity improvement that can be expected given various mitigation factors. Transportation agencies may find work zone capacity estimates useful when planning construction in critical urban centers.

Optimal Trajectory Control for Left-Turn Vehicles at Exit Lane for Left-Turn Intersections

The exit lane for left-turn (EFL) intersection is a newly proposed unconventional intersection that can alleviate left-turn traffic congestion at intersections. The EFL design characteristic lies in that a part of exit lanes can be provisionally used as left-turn lanes to provide additional capacity for left-turn traffic. The inappropriate lane selection of human drivers decreases the effectiveness of such design. This paper establishes an optimal trajectory planning model for left-turn vehicles at EFL intersections under the automated driving environment. The longitudinal acceleration and lane changing variables are optimized simultaneously. The optimization model is formulated as a mixed-integer linear model, which ensures the computational efficiency. The effectiveness of the proposed model is explored under various traffic, geometric, and signal control conditions. The results show that the model can provide a suitable control strategy for left-turn vehicles. On average, traffic delay can be reduced by 47.3%. The proposed model has a promising control effect under high volume conditions. Moreover, the proposed model performs stably under the various length of the mixed-usage area.

PROJECT PLANNING PROYEK PEMBANGUNAN APARTEMEN TAMANSARI BINTARO MANSION KOTA TANGERANG SELATAN

Tamansari Bintaro Mansion Apartment construction project by PT. Wika Realty South Tangerang has a building area of 40.695 m2 and on a site area of 6.500 m2 . This high-rise apartment consist of 30 floors and 2 underground floors. However, author only plan to stage 1, which consists of 13 floors and 2 underground floors. The data used were shop drawings, Work Plans and Conditions, and South Tangerang City HSPK in 2019. The Occupational Health Safety Review were reviewed based on the Number 4 in 1987 and OHSAS 18001:2007. This plan resulted in an alternative project planning: the first was to use two tower cranes and two passenger hoist. The author also plans traffic management alterative by planning to use a two-lane one gate system, left access entry lane and right access exit lane. The implementation method uses a bottom-up method as an alternative. Standard Operating Procedures and Quality Targets created for the implementation quality assurance; safety plan, HSE (Health, Safety, and Environment) organizational structure, HSE equipment plan, and HSE schedule were created for HSE implementation. Bottom-up method in the site costs Rp.74.155.806.619,69 with 434 calendar days

Managing Heat Stress In Dairy Facilities

Heat stress can have a dramatic impact on milk production and reproduction on commercial dairies. The impact of heat stress can be minimized by improving water availability, providing shade in the housing areas and holding pen, reducing walking distance, reducing time in the holding pen, improving holding pen ventilation, adding holding pen cooling and exit lane cooling, improving ventilation in cow housing areas (freestalls), cooling close-up cows (3 weeks prior to calving), cooling fresh cows and early lactation cows, and cooling mid and late lactation cows. Dairy cattle can be cooled by providing a cooler environment (cooling the air) or by soaking the cows and evaporating water off her skin surface (cooling the cow). Using evaporative cooling to cool the air works in climates with low relative humidity. Evaporating water off the skin surface of the cow to cool the cow will be beneficial in all climates.

Analysis of the Trajectories of Left-turning Vehicles at Signalized Intersections

Internationally, an annual number of more than a million fatalities are caused by road traffic crashes, with particularly signalized intersections being crash prone locations within the highway system. An accumulation of conflicts between drivers is caused by the different movements (through and turning) from different directions at the intersection; hence, studying the trajectories of turning vehicles is an important step towards improving traffic safety performance of these facilities. In view of that, the current paper aims at providing further insight into the behaviour of left-turning vehicles (right-hand traffic rule) at signalized intersections in the State of Qatar. At first, a total of 44 trajectories of free-flowing vehicles were manually extracted from a recorded video for a single approach of Lekhwair signalized intersection in Doha City, State of Qatar. After that, the extracted trajectories were statistically analysed in an attempt to explore the factors affecting the path of left-turning vehicles at signalized intersections. The results suggest that the characteristics of the extracted paths are significantly related to the vehicle’s entry speed, minimum speed throughout its turning manoeuvre, and the lateral distance between the exit point and the curb (i.e., targeted exit lane). Provided that the speed parameters can be fairly an indication to the driving behaviour, it can be concluded that the driver’s attitude plays an important role in drawing the manoeuvre of a turning vehicle as does the pre-selection of the exit lane. Finally, the effort presented in this paper can be regarded as a way forward towards understanding the behaviour of turning vehicles at signalised intersection in the State of Qatar.

Exit lane allocation with the lane-based signal optimization method at isolated intersections

In signal optimization problems, incompatible movements are usually in either of two states: predecessor or successor. However, if the exit lane is well allocated, the incompatible movements merging at the same destination arm can exist in parallel. The corresponding longer green duration is expected to increase the capacity of intersections. This paper aims to solve the exit lane allocation problem with the lane-based method by applying the three states among incompatible movements at conventional signalized intersections. After introducing auxiliary variables, the problem is formulated as a mixed integer programming and can be solved using a standard branch-and-cut algorithm. In addition to the exit lane allocation results, this proposed method can also determine the cycle length, green duration, start of green, and signal sequence. The results show that the proposed method can obtain a higher capacity than that without the exit lane allocation. The pavement markings are further suggested for safety.

Effects of Short Exit Lane on Gap-Acceptance and Merging Behavior of Drivers Turning Right at Unconventional T-Junctions

The right turn from minor road at a three-legged or T-junction with stop control is a critical movement as it needs to yield to four other movements on the major road. This study aims to investigate and compare the effects of short exit lane and merging behavior of vehicles turning right at unconventional T-junction with conventional T-junction. Field studies were conducted at three types of T-junctions to study the gap acceptance of vehicles turning right and the merging behavior of vehicles turning right with vehicles on the major road using pneumatic road tubes and video camera. The results indicated that the critical gap and follow-up times for T-junctions with exit lanes decreases by 16% and 10%, respectively. Additionally, the average speed of vehicles turning right with a short exit lane is approximately 30 km/h. Findings also show that 22.1% of vehicles on the major road reduce their speed more than 5 km/h when interacting with right-turning vehicles at T-junction with a short right-turn exit lane. Conversely, up to 55.4% of vehicles reduce their speed by 5 km/h or more when interacting with vehicles turning right at T-junction with a short through exit lane. These findings proved that the presence of a short right-turn exit lane at T-junction can reduce the conflict between right-turn movement from the minor road with through movement of the major road. Therefore, outcomes from this study are important as they can contribute to improving the design approach of unsignalized intersections.

Factors associated with productivity on automatic milking system dairy farms in the Upper Midwest United States

The objective of this study was to identify housing and management factors associated with productivity on automatic milking system (AMS) dairy farms measured as daily milk yield/AMS and daily milk yield/cow. Management, housing, and lameness prevalence data were collected from 33 AMS farms in Minnesota and Wisconsin during a farm visit. All farms in the study used free-flow cow traffic. Mixed model analysis of cross-sectional data showed that farms with automatic feed push-up via a robot produced more milk per AMS/day and per cow/day than farms where feed was pushed up manually. New versus retrofitted facility, freestall surface, manure removal system, and the number of AMS units/pen were not associated with daily milk yield per AMS or per cow. Cow comfort index (calculated as number of cows lying down in stalls divided by total number of cows touching a stall) was positively associated with daily milk yield/cow. Prevalence of lameness and severe lameness, number of cows per full-time employee, depth of the area in front of the AMS milking station, and length of the exit lane from the AMS milking station were not associated with daily milk yield per AMS or per cow. Multivariable mixed model analysis of longitudinal AMS software data collected daily over approximately an 18-mo period from 32 of the farms found a positive association between daily milk yield/AMS and average age of the cows, cow milking frequency, cow milking speed, number of cows/AMS, and daily amount of concentrate feed offered/cow in the AMS. Factors negatively associated with daily milk yield/AMS were number of failed and refused cow visits to the AMS, treatment time (the time spent preparing the udder before milking and applying a teat disinfectant after milking), and amount of residual concentrate feed/cow. Similar results were also found for daily milk yield on a per cow basis; however, as it would be expected, average days in milk of the herd were also negatively associated with daily milk yield/cow. These findings indicate that several management and cow factors must be managed well to optimize AMS productivity.

Dynamic simulation and characteristics analysis of traffic noise at roundabout and signalized intersections

Traffic noise prediction is an important topic for traffic environment planning in cities. The complex traffic flow at road intersections makes the prediction of traffic noise challenging. In this paper, a dynamic traffic noise simulation method based on microscopic traffic simulation is used to study the traffic noise near roundabout and signalized intersections. A vehicle noise emission model that considers the effect of acceleration is established using an experimental method. The accuracy of the model is verified by comparison with measured data. Traffic noise near roundabout and signalized intersections under different traffic volume levels is simulated, and the results are compared. Some significant relations between traffic noise and traffic volume are obtained, and the mechanisms are analyzed. The results show that traffic noise reaches an upper limit when traffic is saturated, and the noise energy contribution of the exit lane is far greater than that of the entrance lane.

Robust Optimal Lane Allocation for Isolated Intersections

AbstractLane allocation including approach and exit lane numbers and lane markings of approach lanes plays an important role in improving the capacity of an intersection. Conventional approaches for optimizing lane allocation often ignore fluctuations in traffic demand (TD). This article presents a stochastic model for robust optimal lane allocation of an isolated intersection under stochastic traffic conditions. This model is built in three steps. In the first step, an enhanced lane‐based model in the form of a binary mixed‐integer nonlinear program is proposed to optimize lane allocation and traffic signals for both vehicles and pedestrians in a unified framework under deterministic traffic conditions. In the second step, a two‐level stochastic model is developed to obtain a robust lane allocation that is less sensitive to traffic flow fluctuations considering the flexibility of traffic signals. In the third step, the two‐level model is further transformed into a TD‐based stochastic model in a two‐phase form to reduce the solution dimension for efficient computation. A TD‐based genetic algorithm procedure is presented for solvability. Numerical studies are conducted to validate the model formulations and solution algorithms.

Extent of Priority Stream Delays at Midblock Median Opening Zone

The study is concerned with investigating delays and queues in both flow directions of exclusive U-turn median openings zone. Note that other turning movements are not allowed at exclusive U-turn median openings zone. Travel time delay study was carried out at four sites in Johor, Malaysia. Resultsshow that average delay of 5s can be expected at divergingsection and no significant delay to conflicting traffic flows at the merging section. Delayswere recorded for vehicles waiting to merge at the exit lane. The paper concluded that weaving may be called to account for travel time delay at the diverging section. And also that since vehicle at the merging section must give way, there will be no delay to conflicting traffic flow.

EVALUATING THE OPERATIONAL AND THE ENVIRONMENTAL BENEFITS OF A SMART ROUNDABOUT

Vehicle fuel consumption and emission rates in Kuwait have increased considerably over recent decades, and are now causing health and economic problems. A three-lane smart roundabout is a new and innovative design idea that can help to mitigate these issues. The smart roundabout was designed with a dedicated exit lane on the right side of each entryway, and a U-turn path connecting each adjacent entry and exit road. Both features permit vehicles to turn in specific directions without needing to enter the roundabout itself. Underground tunnels were designed for pedestrian and cyclist use. The objective of this study was to measure the impact of a smart roundabout on vehicle fuel consumption and on emissions of carbon dioxide, carbon monoxide, nitrogen oxides, and hydrocarbons. These results were then compared with those of a traditional roundabout and of a light-signalised intersection. Two light-signalised intersections with different traffic volumes were chosen for this study and simulated in their present state, as replaced by traditional roundabouts; and as replaced by smart roundabouts using the SIDRA 6.0 software. The smart roundabout allowed traffic to proceed with minimal delay and idling time, significantly reducing vehicle fuel consumption and emissions in comparison with a traditional roundabout or light-signalised intersection. Furthermore, the smart roundabout allowed pedestrians and cyclists to move safely through the intersection without interacting with vehicular traffic

Real-Time Estimation of Lane-to-Lane Turning Flows at Isolated Signalized Junctions

In this paper, we develop rule- and model-based approaches for the real-time estimation of lane-to-lane turning flows. Our aim is to determine the turning proportions of vehicles based on detector information at isolated signalized junctions and thereby establish effective control strategies for adaptive traffic control systems. The key concept involves identifying the entrance lane of a vehicle detected in an exit lane at the signalized junction. Lane-to-lane turning flows are estimated by tracing the corresponding entrance lanes of the vehicle based on the detector and signal information from the set of potential entrance lanes at the junction. In the rule-based approach, the entrance lane of a vehicle detected in an exit lane is identified according to a set of specified rules. The model-based approach, which is based on utility maximization, is used to identify the most probable turns in a set of potential upstream entrance lanes. Both computer simulations and real-world traffic data show that the model-based approach outperforms the rule-based approach, particularly when turning on red is allowed, and is capable of accurate estimation under a wide range of traffic conditions in real time. However, the rule-based approach is simpler and does not require calibration, which are positive assets when no prior data are available for calibration.

Evaluation of Truncated Arrow per Lane Guide Signs

Some freeway and expressway interchanges contain an interior option lane in which traffic in that lane can choose to exit or remain on the route at the split. The 2009 Manual on Uniform Traffic Control Devices requires that either the Overhead Arrow per Lane or the diagrammatic guide sign designs be used for all multilane exits at major interchanges that have an optional exit lane that also carries the through route. However, some practitioners believe that it is cost-prohibitive and unnecessary to install Overhead Arrow per Lane guide signs at minor interchanges. Given the benefits of Overhead Arrow per Lane guide signs, a condensed version of an Overhead Arrow per Lane guide sign is needed for use where a full Overhead Arrow per Lane guide sign is not a reasonable option. A truncated version of the sign, which could be displayed on existing cantilever structures, would eliminate the expense of installing larger structures while still reaping the benefits of the Arrow per Lane sign concept. This study identified five signing alternatives for potential use at minor and intermediate interchanges with multilane exits and an option lane. Participants viewed videos of either Overhead Arrow per Lane guide signs or one of the four truncated alternatives. Participants were asked to indicate which lanes they could use to exit in some scenarios and which to use to proceed through in other scenarios. Participants typically understood the alternatives that provided information about both through and exiting traffic (80% comprehension), whereas alternatives that provided information about exiting traffic, with little to no information about through traffic, resulted in relatively low comprehension (38%).

Characteristics and optimization of traffic flow in a two-off-ramp system

In this paper, a multi-lane cellular automata model is adopted to investigate the evolution of traffic flow in a two-off-ramp system. The variable message sign (VMS) is used to realize traffic flow guidance. More attention is paid to the decision-making behaviors of the driver, i.e., choosing the target off-ramp and its influence on road capacity. The original model without VMS and the improved model with VMS are proposed respectively. Through numerical simulation, the corresponding phase diagram, the capacity, the flux of each section and typical patterns are obtained, then the effects of the injection probabilities, the fraction of leaving vehicles and the length of the exit lane on capacity are analyzed in detail. When the length of the exit lane is rather short but the entering probability and the fraction of leaving vehicles are rather large, the road capacity is increased noticeably with the help of VMS and therefore the state of traffic flow is improved. It is shown that the utilization efficiency of downstream off-ramp is enhanced and traffic jams are alleviated due to the guidance of VMS.