Work Zone Research Articles

Lane Optimization of Highway Reconstruction and Expansion Work Zone Considering Carbon Dioxide Emission Factors

During the highway reconstruction and expansion, some lanes are often closed on the construction side to ensure that the construction is carried out normally. The presence of the work zone increases the traffic pressure on the construction side of the highway, causing traffic congestion, increased CO2 emissions from motor vehicles, and increasing environmental pollution. The bi-level programming model was developed based on the objective of minimizing the travel time and total CO2 emissions of the system so as to solve it using a quantum particle swarm algorithm with high convergence speed and high intelligence to form the lane optimization scheme for the three forms of reclosing and expanding six-lane highways in both directions. The results show that reasonable use of opposite non-construction lanes in the work zone of a partially closed highway expansion can reduce the total system travel cost, alleviate traffic congestion, reduce CO2 emissions, and contribute to the sustainable development of transportation, as well as the environment.

Measuring Roadway Lane Widths Using Connected Vehicle Sensor Data.

The United States has over three trillion vehicle miles of travel annually on over four million miles of public roadways, which require regular maintenance. To maintain and improve these facilities, agencies often temporarily close lanes, reconfigure lane geometry, or completely close the road depending on the scope of the construction project. Lane widths of less than 11 feet in construction zones can impact highway capacity and crash rates. Crash data can be used to identify locations where the road geometry could be improved. However, this is a manual process that does not scale well. This paper describes findings for using data from onboard sensors in production vehicles for measuring lane widths. Over 200 miles of roadway on US-52, US-41, and I-65 in Indiana were measured using vehicle sensor data and compared with mobile LiDAR point clouds as ground truth and had a root mean square error of approximately 0.24 feet. The novelty of these results is that vehicle sensors can identify when work zones use lane widths substantially narrower than the 11 foot standard at a network level and can be used to aid in the inspection and verification of construction specification conformity. This information would contribute to the construction inspection performed by agencies in a safer, more efficient way.

A methodology for scheduling within‐day roadway work zones using deep neural networks and active learning

AbstractCity infrastructure agencies routinely implement road projects that address various elements of urban infrastructure. The majority of these projects are short‐term in nature (e.g., utility repair), as they are completed in a few hours within 8:00 a.m. to 5:00 p.m. of a workday. The implementation of these projects during working hours, in spite of the inconvenience imposed on road users, helps the agency avoid extra labor costs associated with nonregular working hours. Careful scheduling of these projects can prevent unduly increased travel delays (road users’ interest) while keeping project costs low (the agency's interest). This study presents a bi‐level framework for scheduling short‐term urban road projects that analyzes the implicit tradeoffs between the two stakeholders’ interests. The upper‐level model establishes the optimal schedule considering the project characteristics, such as cost and duration. The lower‐level model captures the dynamic user equilibrium conditions that yield the road users’ path and departure time choices. The bi‐level model is a mixed‐integer program with nonlinear constraints. Recognizing the relatively low efficiency of traditional solution methods, this paper proposes a deep‐neural‐network‐ensemble‐assisted active learning (DN2EA2L) algorithm and adopts a fixed‐point algorithm for solving the bi‐level model. The numerical experiment uses the Sioux Falls network to demonstrate the efficiency of the DN2EA2L, compared to conventional metaheuristic methods. It is shown that travel time increases due to the project implementation during the peak hours can outweigh the agency's saving in wage costs. Further, it is shown that a significant reduction in the road users’ value of time enables the agency to schedule more projects during regular working hours.

Assessment of Driver Distraction at Work Zones with Portable Rumble Strip Deployments in Texas

The objective of this research was to assess the extent of distracted driving occurring on roadways in Texas, U.S., as drivers approach a work zone and the extent to which portable rumble strips (PRS) may influence those rates. The research team utilized direct field observations of drivers approaching work zones at several Texas work zones. At each work zone, team members positioned themselves near the location of the upstream set of PRS. Team members also collected observational data at a second location downstream from that initial PRS location. The results of the field studies showed that nearly one in five motorists are visually distracted in some manner while driving as they approach a work zone. The studies also showed that this rate of visual distraction decreased at distances closer to the work zone. Observations of distracted drivers as they passed over the PRS indicate that at least some of that decrease in distraction over distance was because of the presence of the PRS. Data were not sufficient to determine conclusively how long the distraction-reducing effects of PRS last. However, data from one site suggest that the effect was limited to the first 1,500 ft after traversing the PRS.

Inferring heterogeneous treatment effects of work zones on crashes

The increasing number of work zone crashes has been a significant concern for road users, transportation agencies, and researchers. Crashes can be caused by work zones, and this effect changes across different work zone configurations, traffic volumes, roadway functional classifications, and weather conditions. This is typically represented by Crash Modification Functions (CMFunctions). However, current methods for developing work zone CMFunctions have two major limitations: (1) They focus on analyzing statistical associations and fail to mitigate the confounding bias due to possible unobservable roadway characteristics; and (2) They cannot address CMFunctions of multiple variables simultaneously, such as weather and traffic conditions, since they are represented using mixed data types (continuous and categorical) that could potentially affect the causal effect of work zones on crashes. In this study, we develop a method that utilizes causal forest with fixed-effect modeling to mitigate the confounding bias while identifying CMFunctions conditioning on various environmental characteristics, including work zone configurations, traffic volume, roadway functional classification, and weather conditions. The developed method was applied to 3378 work zones that occurred in Pennsylvania between 2015 and 2017. The results were validated via a series of robustness tests. The validations demonstrate that this method can mitigate the confounding bias and identify CMFunctions of multiple variables. The results also show that the causal effect of a work zone on crash occurrence is significantly positive (p<0.05) on roadways with high traffic volumes (e.g., > 20,000 vehicles per day) and on medium length (e.g., 2000 to 5000 m) work zones. It appears that having medium–long (e.g., between 6000 and 8000 m) work zones or long duration (e.g., longer than 4 h) work zones do not necessarily lead to extra crashes.

Clear Lens Protection with a Phakic Posterior Chamber IOL During Iridoplasty

A 20-year-old man with a light-blue iris presented himself with fixed unilateral mydriasis, clear lens, a small inferior zonular dialysis, normal intraocular pressure (IOP), an uncorrected vision of 0.0 LogMAR, and retained accommodation. An assault 6 months before was reported. He asked for mydriasis reversal to decrease photophobia and to improve cosmesis. He wanted to avoid lens removal. We planned an encircling iris suture, and for protection a temporary implantation of a myopic phakic posterior chamber intraocular lens (Visian ICL), that results thicker in the foreseen working zone.

Calibration and Validation of a Microsimulation Model of Lane Closures on a Two-Lane Highway Work Zone

Lane closure on a two-lane work zone can negatively affect operational performance. Although a microsimulation model is often used to quantify and predict these negative impacts, it requires proper calibration to produce meaningful results. The sixth edition of the Highway Capacity Manual (HCM-6) proposed a microsimulation model using limited empirical data from King County, Washington. Based on the authors’ knowledge, this paper is the first to examine the applicability of the HCM-6 two-lane work zone model in a different geographical area. A preliminary application of the HCM-6 model to two test sites in Nebraska found that the HCM-6 estimation of the mean headways and travel times were statistically different from observed data at the 5% significance level. Therefore, this paper proposed an automatic microsimulation calibration methodology for identifying parameters that can match the distribution or the mean value of observed traffic data. To the best of the authors’ knowledge, this is the first paper to show that a two-lane work zone microsimulation model calibrated using the empirical distributions of traffic measures can replicate the corresponding distributions at the 5% significance level. However, if the model was calibrated using the mean value of traffic measures, it could not replicate empirical distributions. This model was also validated using field data not used for calibration. The methodology proposed in this paper will benefit those who design and operate work zones because traffic agencies are interested in the variety of traffic conditions, not just the average. This paper concludes with a discussion on model transferability.

Моделирование совмещенного нагрева для абляции опухолей

In the field of oncology therapy in the last few decades, methods of local thermal destruction have been intensively developed, which is heating a malignant neoplasm to a coagulation temperature and above. Among them, radiofrequency ablation (RFA) and microwave ablation (MWA) are the most common. The main problem of the existing MWA and RFA units is the insufficient degree of tissue coagulation. Depending on the type of tissue, various methods of exposure to an electromagnetic field can be used. In the radio frequency (RF) range, ohmic heating can be used, suitable for highly conductive tissues, and dielectric heating for low conductivity tissues. To increase the heating volume, it is proposed to combine ohmic and dielectric heating. The purpose of this work was to study the possibility of combining the processes of ohmic and dielectric heating based on methods of microwave and radiofrequency thermal destruction. A computer simulation of the combined heating electrode was carried out. The COMSOL Multiphysics software package was used to create the model. The algorithm for constructing the model consisted in creating the geometry, choosing the sizes of the working zones of the electrodes, setting the power parameters and imposing a finite element mesh. The model was two-dimensional. Various configurations of the combined heating electrode were considered. As a result, it was found that it is possible to create a heating area of a larger volume than with separate exposure. The overall shape of the resulting heating in all cases had an elliptical shape. At the same time, the heating pattern for RF working zones with a size of 5 mm had a shape more suitable for the treatment of spherical tumors than for working zones with a size of 10–20 mm. The results obtained demonstrate the possibility of increasing the heating volume by more than 40% compared to single operating modes. The most suitable sizes of RF heating zones are calculated, at which the heating volume will be maximum. The use of combined heating in clinical practice will partially solve the problems of insufficient heating volume inherent in the single-electrode heating mode in both RFA and MWA.

Crash prediction for freeway work zones in real time: A comparison between Convolutional Neural Network and Binary Logistic Regression model

Safety of drivers in freeway work zones has been a problem. Real-time crash prediction helps prevent crashes before they happen. This paper looks at real-time crash prediction in freeway work zones by using machine learning approaches. Both the Convolutional Neural Network and the Binary Logistic Regression model are introduced. For training and testing the models, crash data and traffic data from several freeways in D7 zone, Los Angeles, California, were used. Crash data were collected from California Highway Patrol Incident System, and traffic data were obtained from the Caltrans Performance Measurement System. Data processing and matching were conducted. Both the two models were trained and tested. Results show that the Convolutional Neural Network performed slightly better over the Binary Logistic Regression model in predicting crashes with a global accuracy of 79.50%. Despite this, the main merit of the Binary Logistic Regression model is that it is able estimate the impact of affecting variables on the probability of crashes and can help identify the factors related to risks in work zones. Machine learning approaches applied in this study perform well in crash prediction. In general, machine learning techniques and reliable real-time crash prediction applications can be promising in helping drivers and transportation engineers make timely responses to potential crashes on freeways.

A comparative study on modified and optimized Zerilli-Armstrong and arrhenius-type constitutive models to predict the hot deformation behavior in 30Si2MnCrMoVE steel

To better understand the elevated temperature flow behaviors of 30Si2MnCrMoVE low-alloy ultra-high strength steel, hot compressive deformation tests were performed at a wide range of forming temperatures (1123–1423 K) and strain rates (0.01–1s−1). The constitutive equations of the material were established through the physical-based modified Zerilli-Armstrong (ZA) and phenomenological Arrhenius-type models, along with the optimized ZA model of strain compensation constructed based on the modified ZA model. Suitability of these models were evaluated by comparing the correlation coefficient and absolute average error between the prediction and experimental data, its ability to predict the deformation behavior, and the amount of calculation required for the material constants. Results show that the modified ZA model cannot accurately describe the flow behavior of the 30Si2MnCrMoVE steel in the abovementioned hot working zone. The optimized ZA model and Arrhenius-Type model based on strain compensation require similar computational effort, and both can effectively predict the high temperature flow behavior of 30Si2MnCrMoVE steel. Relatively, the Arrhenius type model has the highest prediction accuracy.

Examining the Influence of Work Zones on the Propensity of Secondary Crashes

Examining the Influence of Work Zones on the Propensity of Secondary Crashes

A Review on Work Zone Safety During Blackspot Improvement Construction Under Blackspot Management

Abstract: Massive Road building and development is being taken up in India, under various schemes, such as National Highway Development Project (NHDP) and Prime Minister’s Rural Road Development Schemes (PMGSY). Activities of improvement of about 45,000 kms of National Highways and around 400,000 kms of rural roads besides numerous urban roads are going on, all across the country. To ensure safety of all, there is a need to adopt an efficient and effective plan for management of traffic in work zones which are already blackspots. Work Zone Traffic Management Plans (WTMPs) are required to meet the safety needs of regular traffic as well as works traffic, ensuring minimum disruption in access to properties and movement of pedestrians. This research is a case study of road accident scenario on NH-152(Ambala-Zirakpur section). In 28.05 kilometers long stretch it has 24 identified accidental black spots, indicates that about 12-13 km of the road length has engineering faults and lack adequate infrastructure as per the requirements of the vehicles/pedestrians. This research talk about management of activities involved during its blackspot rectification work in work zone areas. As per this approach we have divided whole stretch into 5 corridors and described management of activities with main concern of safety, cost and time. At last, we have compared traditional approach of blackspot improvement and corridor approach of black spot improvement and finally concluded our study in form of guidelines which can be adopted during black spot rectification using corridor approach.

Health and Safety in Temporary Work Zone Road Construction Project in Saudi Arabia: Risks and Solutions.

Road project sites are dangerous and crash-prone, with many hazards that can cause injuries and can result in the deaths of road users or site-workers. Work zones for road construction or maintenance can potentially contribute to increasing these crashes. Many studies have addressed this issue; however, there is a lack of similar studies in Saudi Arabia. Therefore, this study contributes to developing safety practices for road work zones in Saudi Arabia by identifying, analyzing, and controlling the main risk factors. A survey approach was used to identify risk factors and potential countermeasures from road users’ and civil engineering experts’ perceptions. The main findings showed that most participants believed that the presence of work zones on the road might increase the probability of crash occurrence and that the highest risk factor that could cause a crash in a work zone is related to driver behavior. Both groups agreed that strict action against contractors or consultants who have safety violations would enhance road safety in work zones. Considering the findings of this study, decision-makers should take strong action to implement and improve road safety practices.

Characterization, Detection, and Segmentation of Work-Zone Scenes From Naturalistic Driving Data

This paper elucidates the automatic detection and analysis of work zones (construction zones) in naturalistic roadway images. An underlying motivation is to identify locations that may pose a challenge to advanced driver assistance systems (ADAS) or autonomous vehicle navigation systems. We first present an in-depth characterization of work-zone scenes from a custom data set collected from more than a million miles of naturalistic driving data. We then describe two machine learning algorithms based on the ResNet and U-Net architectures. The first approach works in an image classification framework that classifies an image as a work-zone scene or non-work-zone scene. The second algorithm was developed to identify individual components representing evidence of a work zone (signs, barriers, machines, etc.). These systems achieved an [Formula: see text] score of 0.951 for the classification task and an [Formula: see text] score of 0.611 for the segmentation task. We further demonstrate the viability of our proposed models through saliency map analysis and ablation studies. To our knowledge, this is the first study to consider the detection of work zones in large-scale naturalistic data. The systems demonstrate potential for real-time detection of construction zones using forward-looking cameras mounted on automobiles. Such a system can be incorporated with ADAS to assist drivers in navigating through challenging environments such as construction zones, making those areas safer for commuters. The code is available on our GitHub page: https://github.com/VTTI/Segmentation-and-detection-of-work-zone-scenes .

Lumbar plexus safe working zones with lateral lumbar interbody fusion: a systematic review and meta-analysis.

Significant risk of injury to the lumbar plexus and its departing motor and sensory nerves exists with lateral lumbar interbody fusion (LLIF). Several cadaveric and imaging studies have investigated the lumbar plexus position with respect to the vertebral body anteroposterior plane. To date, no systematic review and meta-analysis of the lumbar plexus safe working zones for LLIF has been performed. This systematic review was conducted according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Relevant studies reporting on the position of the lumbar plexus with relation to the vertebral body in the anteroposterior plane were identified from a PubMed database query. Quantitative analysis was performed using Welch's t test. Eighteen studies were included, encompassing 1005 subjects and 2472 intervertebral levels. Eleven studies used supine magnetic resonance imaging (MRI) with in vivo subjects. Seven studies used cadavers, five of which performed dissection in the left lateral decubitus position. A significant correlation (p < 0.001) existed between anterior lumbar plexus displacement and evaluation with in vivo MRI at all levels between L1-L5 compared with cadaveric measurement. Supine position was also associated with significant (p < 0.001) anterior shift of the lumbar plexus at all levels between L1-L5. This is the first comprehensive systematic review and meta-analysis of the lumbar neural components and safe working zones for LLIF. Our analysis suggests that the lumbar plexus is significantly displaced ventrally with the supine compared to lateral decubitus position, and that MRI may overestimate ventral encroachment of lumbar plexus.

In Search of an Effective Workability Zone during the 3D Printing of Polymeric Periodic Open Cellular Structures Potentially Useful as Microreactors

The question of how easy the transition is between design and manufacturing by the 3D printing of periodic open cellular structures occurs from the analysis of cases in which additive manufacturing and heterogeneous catalysis merge. The synergy between these two fields suggests that one of the great advantages that the catalysis of this manufacturing methodology can take advantage of is the obtaining of advanced designs that would allow improving the processes from the geometry of the reactors. However, not all 3D-printing techniques offer the same degree of resolution, and this uncertainty grows when using more complex materials to work with, such as ceramics or metals. Therefore, the present work seeks to answer this question by finding experimentation strategies, starting with a simple case study inspired by the additive manufacturing–catalysis combination, in which a ceramic polymer resin of high thermal resistance is used to obtain POCSs that are potentially useful in thermochemical or adsorption processes. This exploration concludes on the need to define limits for what we have called an “effective work zone” that combines both design criteria and the real possibility of printing and manipulating the pieces, making sweeps in structural parameters such as cell size and the diameter of struts in the POCS. Similarly, the possibility of coating these systems with inorganic oxides is explored, using a generic oxide (Al2O3) to analyse this scenario. Finally, a cartridge-type assembly of these systems is proposed so that they can be explored in future processes by other researchers.

Analysis of Temporal Stability of Contributing Factors to Truck-Involved Crashes at Work Zones in South Carolina

This study examines factors that contributed to truck-involved work zone crash injury in South Carolina, a state which experienced a rise in the number of injury crashes from 2014 to 2018. The outcome of interest is injury or property damage only (PDO) crashes. A binary logit model is developed using South Carolina statewide work zone crash data from 2014 to 2018. It considers various factors, including vehicle, crash, roadway, environment, day and time, and driver-related characteristics. Of particular interest to this study is the temporal stability of the contributing factors from year to year so that a long-term mitigating strategy can be developed. To this end, the test for parameter transferability is used, and it confirms that separate models should be used for each year, except for 2014. The only factor found to be temporally stable across all years (i.e., statistically significant in 2015–2018 models) is airbag deployment. Given that nearly all the factors are temporally unstable, an importance measure is introduced to enable transportation agencies to rank factors and develop countermeasures that target persistent contributing factors. Based on the importance measure, the top three ranked factors that contributed to work zone truck-involved crash injury in South Carolina from 2015 to 2018 are: (i) airbags deployed, (ii) tie between rear-end crashes and crashes on primary roadways, and (iii) crashes in dark conditions.

Fault-Tolerant Control of Variable Speed Limits for Freeway Work Zone With Recurrent Sensor Faults

Congestion associated with freeway work zones can adversely affect mobility, safety, and sustainability. Variable speed limits (VSL) control has been widely studied to mitigate the congestion caused by lane closures at work zones. However, most VSL controllers are designed without consideration of traffic sensor faults, especially recurrent sensor faults (RSFs) that commonly exist in freeway transportation systems. Therefore, this study proposes an interacting multiple model approach with a pseudo-model set (IMMP) to achieve VSL control with fault tolerance to different types of RSFs. With the design of a traffic flow model, an adaptive model set is developed using likelihood estimation to reduce the associated computational complexity. To ensure reliable RSF diagnosis, state covariance adaption is proposed to compensate for potential discrepancies caused by improper model parameters. A pseudo-mode set is designed to provide accurate traffic state estimations for VSL control without the prerequisite of a good match between the model parameters and the extent of corresponding sensor failures. The proposed system is evaluated under a realistic work zone environment using the traffic simulator SUMO. The results demonstrate that the system can achieve reliable RSF diagnosis and consistent improvements in mobility, safety, and sustainability near a freeway work zone area despite RSFs.

Verification and Efficacy of Automated Queue Detection Systems on Interstate Intelligent Work Zones

Intelligent work zones have been widely adopted in the United States because they have been proven to improve traffic safety and operations. One specific intelligent work zone system, known as automatic queue detection (AQD), is designed to measure work zone-related queueing in real time, and inform drivers upstream so they may be prepared to slow down or stop. This paper describes an evaluation of the performance and efficacy of four AQD systems implemented at work zones on Interstate 80 in Nebraska. Specifically, (i) the system performance was verified by examining whether the messages displayed on the portable dynamic message signs (PDMS) were consistent with the underlying AQD logic, and (ii) the system efficacy was measured by determining whether the overall speeds of individual vehicles and the space mean speed (SMS) were reduced when warning messages were provided. It was found that the AQD systems were functioning well as evidenced by an error rate of 0.7 to 2.3%. It was concluded that the SMS was reduced in response to the PDMS warning display indicating that there was slow or stopped traffic ahead. The decrease in SMS was found to be statistically significant and in the range of 3.5 to 7 mph. This was approximately 47% greater than the reduction in SMS that occurred when the PDMS did not display any message. In summary, it was found that the AQD systems were operating correctly and, more importantly, they were effective in reducing the speeds of the traffic stream downstream of the PDMS.

An empirical analysis of driver injury severities in work-zone and non-work-zone crashes involving single-vehicle large trucks

Objectives Florida ranks among the states with the highest rates of work-zone crashes involving large trucks. With significant emphasis in Florida’s strategic highway safety plan, understanding work-zone crashes involving large trucks and resulting injury severities is critically important. This study investigated the contributing factors influencing the driver injury severity of single-large-truck crashes in work zones, benchmarked against non-work zones in Florida. Methods Using work-zone and non-work-zone crash data from 2011 to 2019 (inclusive), driver-injury severities in single-large trucks crashes were studied using random parameters logit models that allow for possible heterogeneity in the means and variances of parameter estimates. The available data included a wide variety of factors known to influence driver injury severity, including spatial and temporal; vehicle and traffic; roadway, harmful events, and driver characteristics. Results The model estimates produced fundamental shift in unobserved heterogeneity for work-zone and non-work-zone crashes involving single large trucks. More importantly, the likelihood of large truck drivers’ injury severity is about fourteen-times higher on rural and six-times higher on urban interstate highways and 1.3 times lower with 10 miles per hour below the posted speed limit for large trucks inside work zones relative to non-work zones. The model results also indicate that the likelihood of severe driver injury is higher for heavy truck (more than 26000 pounds), a lane-shift work-zone configuration, and careless driving in work-zone crashes involving single large trucks. Conclusions The model findings add valuable insights to have profound effects in the safety performance of large trucks and in-vehicle safety technologies, such as, Advanced Driver Assistance Systems, for careful driving along the work-zone segments with lower speed, leading to Automated Driving Systems. These measures include various policy-related safety countermeasures including revisiting traffic control plan for lane-shift on highways specifically for large trucks and developing training modules for Florida registered truck drivers.