@misc{zegre-hemsey_cheskes_johnson_rosamond_cunningham_arnold_schierbeck_claesson_2024, title={Challenges & barriers for real-time integration of drones in emergency cardiac care: Lessons from the United States, Sweden, & Canada}, volume={17}, ISSN={["2666-5204"]}, DOI={10.1016/j.resplu.2024.100554}, abstractNote={Out-of-hospital cardiac arrest (OHCA) is a leading cause of morbidity and mortality in the US and Europe (∼600,000 incident events annually) and around the world (∼3.8 million). With every minute that passes without cardiopulmonary resuscitation or defibrillation, the probability of survival decreases by 10%. Preliminary studies suggest that uncrewed aircraft systems, also known as drones, can deliver automated external defibrillators (AEDs) to OHCA victims faster than ground transport and potentially save lives. To date, the United States (US), Sweden, and Canada have made significant contributions to the knowledge base regarding AED-equipped drones. The purpose of this Special Communication is to explore the challenges and facilitators impacting the progress of AED-equipped drone integration into emergency medicine research and applications in the US, Sweden, and Canada. We also explore opportunities to propel this innovative and important research forward. In this narrative review, we summarize the AED-drone research to date from the US, Sweden, and Canada, including the first drone-assisted delivery of an AED to an OHCA. Further, we compare the research environment, emergency medical systems, and aviation regulatory environment in each country as they apply to OHCA, AEDs, and drones. Finally, we provide recommendations for advancing research and implementation of AED-drone technology into emergency care. The rates that drone technologies have been integrated into both research and real-life emergency care in each country varies considerably. Based on current research, there is significant potential in incorporating AED-equipped drones into the chain of survival for OHCA emergency response. Comparing the different environments and systems in each country revealed ways that each can serve as a facilitator or barrier to future AED-drone research. The US, Sweden, and Canada each offers different challenges and opportunities in this field of research. Together, the international community can learn from one another to optimize integration of AED-equipped drones into emergency systems of care.}, journal={RESUSCITATION PLUS}, author={Zegre-Hemsey, Jessica K. and Cheskes, Sheldon and Johnson, Anna M. and Rosamond, Wayne D. and Cunningham, Christopher J. and Arnold, Evan and Schierbeck, Sofia and Claesson, Andreas}, year={2024}, month={Mar} }
 @article{feng_deng_lau_cauffman_johnson_cunningham_kaber_2023, title={Age differences in driver visual behavior and vehicle control when driving with in-vehicle and on-road deliveries of service logo signs}, volume={93}, ISSN={["1872-8219"]}, DOI={10.1016/j.ergon.2022.103386}, abstractNote={With the advances in vehicle technologies, more information is communicated in real-time to the driver via an in-vehicle interface. In-vehicle messaging may deliver safety-related information such as warnings as well as non-safety-related information such as an upcoming lodging place. While much research has focused on the design of messaging safety-related information, little is known about the best practice in in-vehicle messaging of non-safety-related information. This study investigated the effects of information source and load on driver signage logo identification, glance behavior, and vehicle control among younger, middle-aged and older drivers. The logos were presented on: (1) an on-road sign panel, (2) an in-vehicle display, or (3) a combination of both, with half of the drives showing logo only, and the other half of the drives showing logo plus additional text. The general findings support the use of in-vehicle displays, especially when it is presented simultaneously with on-road signs. In-vehicle displays did not lead to a higher workload or more visual distraction, and simultaneous presentations resulted in slightly better speed control. The findings also showed minimal negative impacts on logo identification from increased information load. Older drivers performed less well in signage identification and vehicle control, and they made longer glances to logo information suggesting design considerations should be made to accommodate specific driver characteristics.}, journal={INTERNATIONAL JOURNAL OF INDUSTRIAL ERGONOMICS}, author={Feng, Jing and Deng, Yulin and Lau, Mei Y. and Cauffman, Stephen J. and Johnson, Ebony and Cunningham, Christopher and Kaber, David B.}, year={2023}, month={Jan} }
 @article{yang_cunningham_brown_2023, title={Quadrant Roadway Intersections: Tradeoffs between Control Delay Savings and Extra Travel Time}, volume={9}, ISSN={["2169-4052"]}, DOI={10.1177/03611981231195056}, abstractNote={ A quadrant roadway intersection (QRI) reduces congestion relative to a four-phase intersection. (Note: this study relates to traffic systems where vehicles drive on the right-hand side of the road.) It does this by removing left-turn traffic from the main intersection, resulting in a two-phase signal. Nevertheless, there is a lack of clear understanding of the tradeoffs between savings in control delay versus extra travel time experienced by the rerouted movements. This research compared the operational performance of five QRI designs with the counterpart conventional intersection (CI) under various traffic demand scenarios via TransModeler microsimulation modeling. Three measures-of-effectiveness (MOEs) were employed: time-in-system (TIS), control delay, and intersection capacity utilization. Simulation results show that all QRI designs outperform CI design for all three MOEs under all demand scenarios. QRIs with direct left-turn design have a smaller average TIS than those with loop left-turn design, indicating that savings in control delays did not offset the extra travel times. Under a relatively low demand condition, a single QRI design can generally balance the tradeoffs between control delay and extra travel time. Under a high demand scenario, a dual or full QRI with direct left-turns is preferred, since it reroutes or partially reroutes left- and right-turn traffic to secondary intersections, thus the main intersection has a lower capacity utilization and can accommodate more through-traffic demands than CI, single QRI, and dual or full QRIs with loop left-turns. }, journal={TRANSPORTATION RESEARCH RECORD}, author={Yang, Guangchuan and Cunningham, Christopher M. and Brown, Michael R.}, year={2023}, month={Sep} }
 @article{lee_cunningham_simpson_2023, title={Safety Evaluation for Conversion From Protected-Only Left-Turn Phasing to Time-of-Day Protected-Permissive Left-Turn Phasing Using Flashing Yellow Arrows}, ISSN={["2169-4052"]}, DOI={10.1177/03611981221149430}, abstractNote={ This study investigated the safety effects of the conversion from a protected-only left turn to protected-permissive left turn with flashing yellow arrow (FYA−PPLT) with time-of-day operation. The observational before–after study with the comparison group method was used to develop crash modification factors (CMFs) for the total crashes and two types of target crashes that involve left-turning vehicles on treated approaches (left-turn−same roadway and rear-end crashes). For all potential crashes, crash reports, crash diagrams, and narratives were manually inspected to identify the actual target crashes. The CMFs were separately developed for a full 24-h day and specific time-of-day based on FYA-PPLT operation, and for two severity categories (all severities and fatal & injury). The results showed that the total crashes for 24 h had a slight increase, whereas the target crashes had substantially larger changes (increase in left-turn−same roadway crashes and decrease in rear-end crashes). When looking at the specific time-of-day use of FYA-PPLT, the increase in left-turn−same roadway crashes was significantly higher than the full 24-h period. This implies that engineers could extend protected-only use more on the fringes of the peak periods to mitigate the increase in left-turn-related crashes. The analysis results also showed a trade-off between left-turn–same roadway and rear-end crashes after the signal conversion. The findings reveal how important it is for engineers to properly understand the safety effects on the different categories of target crashes and time periods when considering the signal conversion from a protected-only left turn to FYA-PPLT. }, journal={TRANSPORTATION RESEARCH RECORD}, author={Lee, Taehun and Cunningham, Christopher and Simpson, Carrie L.}, year={2023}, month={Feb} }
 @article{yang_warchol_cunningham_hummer_2023, title={The potential of signalized offset T-intersections to accommodate new developments}, volume={12}, ISSN={["2046-0449"]}, DOI={10.1016/j.ijtst.2022.01.006}, abstractNote={An offset T-intersection splits a conventional four leg intersection into two three-leg T-intersections to reduce the number of conflicts. While the safety benefits of offset T-intersections have been widely documented, the effects on operations are not well understood. To fix that, this paper employed microsimulation modeling to investigate the differences in operational performance between offset T-intersections and four-leg standard intersections under various traffic demands, intersection spacings, and signal timing schemes for three development types: superstore, hybrid gas station, and residential area. Queue length and delay were employed as measurements of effectiveness. Based on microsimulation modeling, we found that under most of the tested scenarios, offset T-intersections were superior to four-leg intersections in terms of reducing delay for the main street traffic. In addition, we found that the left–right (L-R) offset T-intersection configuration outperformed the right-left (R-L) offset configuration in terms of preventing main-street left turn queue spillback. Based on the simulation results, the paper provided practice-ready guidelines on selecting an optimum intersection configuration for each specific development type given the volume demands and known geometric constraints for a given site.}, number={1}, journal={INTERNATIONAL JOURNAL OF TRANSPORTATION SCIENCE AND TECHNOLOGY}, author={Yang, Guangchuan and Warchol, Shannon and Cunningham, Christopher M. and Hummer, Joseph}, year={2023}, month={Mar}, pages={217–229} }
 @article{lee_cunningham_rouphail_2022, title={Movement-based intersection crash frequency modeling}, ISSN={["1943-9970"]}, DOI={10.1080/19439962.2022.2092571}, abstractNote={Abstract Traditional crash frequency models cannot estimate crash frequency for individual traffic movements at an intersection, which precludes the safety evaluation of individual movements and identification of hazardous ones. This paper proposes a movement-based (MB) model that estimates crash frequency for individual movements as well as for the entire intersection. A base model using the safety performance function form in the Highway Safety Manual was also developed for comparison against the MB model. This study used crashes collected for five to eight years at 41 signalized intersections in North Carolina for the model estimation and validation (21 intersections for the estimation and 20 intersections for the validation). The models were validated using cumulative residual plots, test set validation, and in a case study. The test set validation showed that the MB model yielded slight improvements in estimations compared to the base model (1.17%−5.83% reductions in mean absolute error and 3.32%−6.64% reductions in root-mean-square error). The case study showed the MB model correctly identified hazardous traffic movements that had demonstrable safety problems based on observed and estimated crash frequencies. The MB model will enable engineers to identify hazardous movements and approaches to implement safety improvement countermeasures at the deserving locations and movements.}, journal={JOURNAL OF TRANSPORTATION SAFETY & SECURITY}, author={Lee, Taehun and Cunningham, Christopher and Rouphail, Nagui}, year={2022}, month={Jun} }
 @article{cauffman_lau_deng_cunningham_kaber_feng_2022, title={Research and Design Considerations for Presentation of Non-Safety Related Information via In-Vehicle Displays during Automated Driving}, volume={12}, ISSN={["2076-3417"]}, DOI={10.3390/app122010538}, abstractNote={As automated vehicles become more prevalent on roadways, it is necessary to study driver behaviors in interacting with such systems. With higher levels of vehicle automation, drivers may become less engaged with the roadway environment. As a result, how to effectively bring non-safety related information (e.g., guide and service sign content) to a driver’s attention is an open research question. In this review, we summarize current literature on three domains of research, including: (1) the design and effectiveness of traditional road signage, (2) human factors considerations in vehicle automation design, and (3) current design guidelines for in-vehicle information presentation. Based on the review, including empirical studies, we identify knowledge relevant to communicating road signage information in automated vehicles. We propose a framework highlighting various factors that could determine the effectiveness of in-vehicle messaging. The framework is intended to motivate future research on development of in-vehicle interfaces for highly automated driving.}, number={20}, journal={APPLIED SCIENCES-BASEL}, author={Cauffman, Stephen J. and Lau, Mei and Deng, Yulin and Cunningham, Christopher and Kaber, David B. and Feng, Jing}, year={2022}, month={Oct} }
 @article{johnson_cunningham_arnold_rosamond_zegre-hemsey_2021, title={Impact of Using Drones in Emergency Medicine: What Does the Future Hold?}, volume={13}, ISSN={["1179-1500"]}, url={https://doi.org/10.2147/OAEM.S247020}, DOI={10.2147/OAEM.S247020}, abstractNote={Abstract The use of unmanned aerial vehicles or “drones” has expanded in the last decade, as their technology has become more sophisticated, and costs have decreased. They are now used routinely in farming, environmental surveillance, public safety, commercial product delivery, recreation, and other applications. Health-related applications are only recently becoming more widely explored and accepted. The use of drone technology in emergency medicine is especially promising given the need for a rapid response to enhance patient outcomes. The purpose of this paper is to describe some of the main current and expanding applications of drone technology in emergency medicine and to describe challenges and future opportunities. Current applications being studied include delivery of defibrillators in response to out-of-hospital cardiac arrest, blood and blood products in response to trauma, and rescue medications. Drones are also being studied and actively used in emergency response to search and rescue operations as well as disaster and mass casualty events. Current challenges to expanding their use in emergency medicine and emergency medical system (EMS) include regulation, safety, flying conditions, concerns about privacy, consent, and confidentiality, and details surrounding the development, operation, and maintenance of a medical drone network. Future research is needed to better understand end user perceptions and acceptance. Continued technical advances are needed to increase payload capacities, increase flying distances, and integrate drone networks into existing 9-1-1 and EMS systems. Drones are a promising technology for improving patient survival, outcomes, and quality of life, particularly for those in areas that are remote or that lack funds or infrastructure. Their cost savings compared with ground transportation alone, speed, and convenience make them particularly applicable in the field of emergency medicine. Research to date suggests that use of drones in emergency medicine is feasible, will be accepted by the public, is cost-effective, and has broad application.}, journal={OPEN ACCESS EMERGENCY MEDICINE}, publisher={Informa UK Limited}, author={Johnson, Anna and Cunningham, Christopher and Arnold, Evan and Rosamond, Wayne and Zegre-Hemsey, Jessica}, year={2021}, pages={487–498} }
 @article{ahmed_warchol_cunningham_rouphail_2021, title={Mobility Assessment of Pedestrian and Bicycle Treatments at Complex Continuous Flow Intersections}, volume={147}, ISSN={["2473-2893"]}, url={https://doi.org/10.1061/JTEPBS.0000512}, DOI={10.1061/JTEPBS.0000512}, abstractNote={AbstractThis study evaluated the mobility performance of pedestrian-bicycle crossing alternatives at continuous flow intersections (CFIs). CFI crossing types were compared with a standard intersect...}, number={5}, journal={JOURNAL OF TRANSPORTATION ENGINEERING PART A-SYSTEMS}, publisher={American Society of Civil Engineers (ASCE)}, author={Ahmed, Ishtiak and Warchol, Shannon and Cunningham, Chris and Rouphail, Nagui}, year={2021}, month={May} }
 @article{aghdashi_davis_chase_cunningham_2020, title={Modeling and Validating Traffic Responsive Ramp Metering in the Highway Capacity Manual Context}, volume={2674}, ISSN={["2169-4052"]}, DOI={10.1177/0361198120949533}, abstractNote={ This paper presents a methodology for modeling traffic responsive (or adaptive) ramp metering in the freeway facilities method based on the sixth edition of the Highway Capacity Manual (HCM6). Currently, the HCM only provides an option to meter on-ramps as user input using 15-min average flow rates with a focus on planning-level analyses. As a result, the possibilities for simulating and modeling ramp meters with any traffic responsive ramp metering algorithm in the HCM context are limited. Moreover, the freeway facilities methodology in the HCM plays a vital role in the analysis of travel time reliability, which is built on a set of operational scenarios. However, with the lack of traffic responsive ramp metering, analysts are burdened with the task of manually entering average effective ramp metering rates for each on-ramp within the set of reliability scenarios. This process can require a substantial amount of time, in addition to increasing the potential for inaccuracy and bias in freeway and performance measure estimations. As a result, this paper is designed to fill a significant research gap by providing a method for analyzing traffic responsive (or adaptive) ramp metering, an active traffic and demand management strategy, using the core freeway facilities methodology in the HCM. The direct application of the method focuses on the MaxView metering algorithm. However, the proposed framework can be used to model any traffic responsive ramp metering algorithm. The results are validated using real-world sites located on the I-540 westbound freeway corridor in North Carolina. }, number={12}, journal={TRANSPORTATION RESEARCH RECORD}, author={Aghdashi, Seyedbehzad and Davis, Joy and Chase, Thomas and Cunningham, Chris}, year={2020}, month={Dec}, pages={91–102} }
 @article{nye_cunningham_byrom_2019, title={National-Level Safety Evaluation of Diverging Diamond Interchanges}, volume={2673}, ISSN={["2169-4052"]}, DOI={10.1177/0361198119849589}, abstractNote={ A national-level safety evaluation of Diverging Diamond Interchanges (DDIs) in the United States was completed. This study aimed to update previous evaluations and to expand the treatment group size of previous studies to provide a more robust and reliable safety assessment of DDI deployments. For this particular treatment, it was determined that, of the observational before-and-after evaluation methodologies, the comparison group approach yields the best evaluation results. The naïve method can be influenced by outside factors that cannot be accounted for (weather, crash reporting tendencies, etc.). The empirical Bayes method is unnecessary as DDIs are installed for operational benefits, meaning that risk of selection bias and regression-to-the-mean is minimal. This study recommends a total crashes crash modification factor (CMF) of 0.633 based on the comparison group analysis of 26 DDIs in 11 states. The comparison group method was also applied to a variety of crash variables for this study. Angle, rear-end, and sideswipe crashes were found to have CMFs of 0.441, 0.549, and 1.139, respectively. Fatal-and-injury crashes provided a CMF of 0.461. Daytime and nighttime crashes provided CMFs of 0.648 and 0.638, respectively. }, number={7}, journal={TRANSPORTATION RESEARCH RECORD}, author={Nye, Timothy S. and Cunningham, Christopher M. and Byrom, Elizabeth}, year={2019}, month={Jul}, pages={696–708} }
 @article{yeom_schroeder_cunningham_salamati_rouphail_2017, title={Lane utilization model development for diverging diamond interchanges}, number={2618}, journal={Transportation Research Record}, author={Yeom, C. and Schroeder, B. J. and Cunningham, C. and Salamati, K. and Rouphail, N. M.}, year={2017}, pages={27–37} }
 @article{davis_cunningham_findley_searcy_martin_watkins_2017, title={Relating Public Opinions of Roadway Assets to Field Data with Survey and Focus Groups}, volume={2613}, ISSN={["2169-4052"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85015798523&partnerID=MN8TOARS}, DOI={10.3141/2613-03}, abstractNote={ In recent years, transportation policy in the United States has increasingly focused on measuring and tracking performance outcomes. However, identifying how quantifiable outcomes—such as international roughness index ratings—influence less tangible outcomes—such as user satisfaction with a roadway—can be challenging. This paper outlines a method that enables researchers to compare stakeholder perceptions of assets with actual field-measured data for roadways. More than 350 residents in six locations in the state of North Carolina were surveyed about how those residents perceived and prioritized the roadway assets managed by the North Carolina Department of Transportation. Using a method termed “roadway reviews,” researchers asked participants about state-maintained roads as the participants were driven on those roads in real time; these surveys were supplemented with focus groups. In addition to identifying how well asset conditions on roadway segments aligned with the basic expectations of roadway users, researchers determined how these ratings compared with field measurements for the segments and captured how participants ranked the importance of specific roadway assets for overall condition, safety, and appearance. The findings will be used to improve asset management practice and will be integrated into the North Carolina Department of Transportation’s annual Highway Performance Monitoring System reports. }, number={2613}, journal={TRANSPORTATION RESEARCH RECORD}, publisher={Transportation Research Board of the National Academies}, author={Davis, Joy and Cunningham, Chris and Findley, Daniel and Searcy, Sarah and Martin, James and Watkins, Lonnie}, year={2017}, pages={16–28} }
 @article{warchol_chase_cunningham_2017, title={Use of Microsimulation to Evaluate Signal-Phasing Schemes at Diverging Diamond Interchanges}, ISSN={["2169-4052"]}, DOI={10.3141/2620-02}, abstractNote={ Even though diverging diamond interchanges (DDIs) have been the subject of research for more than a decade, the effort to standardize interchange signal timing has developed only recently. A three-factor fully crossed experiment was conducted to investigate the influence of crossover spacing and increased volumes on the performance of DDI phasing schemes. PTV Vistro software and the dynamic bandwidth assessment tool were used to optimize the split, cycle length, and offset of each of the 72 treatments. PTV Vissim software was used to collect microsimulation data. Mean interchange delay and mean stops per vehicle were selected as measures of effectiveness. Pairwise comparisons were used to determine whether an existing preferred phasing scheme could minimize delays or stops under three cases: ( a) given spacing and increased volume, ( b) given volume independent of spacing, and ( c) given spacing independent of increased volume. The data revealed that a two- or three-critical-movement phasing scheme usually resulted in the lowest mean interchange delay and the fewest stops. Overall, the results provide an initial signal timing scheme for practitioners given a crossover spacing, an increased volume, or both. Future work will include exploring low volumes, balanced interchange volumes, and their effects on the four-critical-movement phasing scheme, as well as the effect of closely spaced adjacent intersections. }, number={2620}, journal={TRANSPORTATION RESEARCH RECORD}, author={Warchol, Shannon and Chase, Thomas and Cunningham, Christopher}, year={2017}, pages={10–19} }
 @article{graves_kelly_cunningham_2016, title={An assessment of highway capacity manual default saturation flow rates to those in North Carolina}, volume={86}, number={11}, journal={ITE Journal}, author={Graves, T. and Kelly, B. and Cunningham, C.}, year={2016}, pages={38–43} }
 @article{warchol_schroeder_cunningham_2016, title={Impact of exit ramp geometric treatments at diverging diamond interchanges on queue spillback}, number={2556}, journal={Transportation Research Record}, author={Warchol, S. and Schroeder, B. J. and Cunningham, C.}, year={2016}, pages={75–85} }
 @article{cunningham_findley_hovey_foley_smith_fowler_chang_arnold_hummer_2016, title={Improved Asset Management and Inventory Development through Sample Analysis and Vendor-Client Communication}, volume={22}, ISSN={["1943-555X"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84958576470&partnerID=MN8TOARS}, DOI={10.1061/(asce)is.1943-555x.0000260}, abstractNote={AbstractThis study compared output from mobile inventory data collection vehicles to manually collected data techniques with a focus on two-way communications primarily through the submission of a sample data set to be analyzed prior to the submission of a full data set. The interim submittal and feedback to the vendors based on that resulted in a marked improvement in data quality for 5 of the 28 assets studied. After feedback, it is apparent that highway data collection vendors can accurately locate the vast majority of assets, with the primary exception being those that are occluded by vehicles or surrounding landscaping, such as those assets in the median. Along with the locations of assets, vendors showed promise at collecting many of the feature descriptions such as asset type and condition. Many of the elements (location, type, etc.) for a particular asset type that created collection difficulty were only problematic for a particular vendor, which suggests that further improvements may be achieved ...}, number={1}, journal={JOURNAL OF INFRASTRUCTURE SYSTEMS}, author={Cunningham, Christopher M. and Findley, Daniel J. and Hovey, Kyle and Foley, Paul Burke and Smith, Jessica and Fowler, Tyler and Chang, Jeff and Arnold, Jonathan and Hummer, Joseph E.}, year={2016}, month={Mar} }
 @article{kim_warchol_schroeder_cunningham_2016, title={Innovative Method for Remotely Fine-Tuning Offsets Along a Diverging Diamond Interchange Corridor}, ISSN={["2169-4052"]}, DOI={10.3141/2557-04}, abstractNote={ Diverging diamond interchanges (DDIs) are relatively new in the United States, and signal coordination between the crossovers and adjacent intersections is challenging. This paper provides a method for remotely fine-tuning offsets for a DDI and its adjacent intersections. The proposed method uses the dynamic bandwidth analysis tool (DBAT). The tool uses actuated phase times from the signal controller to optimize the dynamic bandwidth on the basis of that entry data set. Four performance measures evaluated the proposed method: delay, stop severity index, maximum queue, and vehicle trajectory plots. The test results confirmed that DBAT provided a better offset solution than other bandwidth optimization tools that generally optimized programmed bandwidth only and did not account for early return to green caused by skipped or gapped-out movements. Under the DBAT offsets, delay for the through movements on the corridor decreased by 52.8% for northbound vehicles and 46.83% for southbound vehicles. The average delay reduction over all measured paths for uncongested and congested scenarios was 13.88% and 3.50%, respectively. The proposed method and workflow can significantly reduce the offset retiming work process. Normally, this manual process takes more than a day, but the proposed method can be completed in less than an hour without visiting the study site. Furthermore, the proposed method can coordinate any set of movements, as well as multiple travel paths. The authors believe that the proposed method and workflow will significantly help both retiming and new timing of arterial signal coordination along DDI corridors and other signal systems. }, number={2557}, journal={TRANSPORTATION RESEARCH RECORD}, author={Kim, SangKey and Warchol, Shannon and Schroeder, Bastian J. and Cunningham, Christopher}, year={2016}, pages={33–43} }
 @article{vaughan_jagadish_bharadwaj_cunningham_schroeder_hummer_findley_rouphail_2016, title={Long-term monitoring of wrong-way maneuvers at diverging diamond interchanges}, number={2484}, journal={Transportation Research Record}, author={Vaughan, C. and Jagadish, C. and Bharadwaj, S. and Cunningham, C. M. and Schroeder, B. J. and Hummer, J. E. and Findley, D. and Rouphail, N. M.}, year={2016}, pages={129–139} }
 @article{hummer_cunningham_srinivasan_warchol_claros_edara_sun_2016, title={Safety Evaluation of Seven of the Earliest Diverging Diamond Interchanges Installed in the United States}, ISSN={["2169-4052"]}, DOI={10.3141/2583-04}, abstractNote={ Diverging diamond interchanges (DDIs) are increasingly popular because they provide improved traffic operations and cost savings. On the basis of theory, DDIs should be safer than conventional diamonds, but previous empirical safety studies have been limited. The objectives of this work were, therefore, to conduct a broader safety evaluation of DDIs and to recommend a crash modification factor (CMF) for the conversion of a conventional diamond to a DDI. The team analyzed seven of the earliest DDIs in the United States. Four were in Missouri and other sites were in Kentucky, New York, and Tennessee. The team collected more than 28 site years of crash and other data before intersection conversion and more than 19 site years of data after their conversion. The primary analysis was before and after with comparison sites to account for trends and potential simultaneous event biases. The results showed that crashes were reduced at most of the sites, and the team recommended a CMF of 0.67, meaning that installation of a DDI to replace a diamond should reduce all crashes by 33%. The reduction in injury crashes was even larger, with the team recommending a CMF of 0.59. Other analyses indicated that DDI installation should mean a substantial reduction of angle and turning crashes, with some reduction in rear-end crashes as well, although rear-end crashes will still be the dominant crash types after DDI installation. Clearly, DDIs offer potential safety benefits, and agencies should consider them strongly as replacements for conventional diamonds. }, number={2583}, journal={TRANSPORTATION RESEARCH RECORD}, author={Hummer, Joseph E. and Cunningham, Christopher M. and Srinivasan, Raghavan and Warchol, Shannon and Claros, Boris and Edara, Praveen and Sun, Carlos}, year={2016}, pages={25–33} }
 @article{cunningham_schroeder_phillips_urbanik_warchol_tanaka_2016, title={Signal Timing for Diverging Diamond Interchanges: Fundamentals, Concepts, and Recommended Applications}, ISSN={["2169-4052"]}, DOI={10.3141/2557-01}, abstractNote={ A diverging diamond interchange (DDI) is an innovative interchange design that is being used with increasing frequency in the United States because of the ability to use existing right-of-way and infrastructure frequently. This paper documents the state of the practice in DDI signal phasing with principles established in the Signal Timing Manual, namely, that it uses consistent phase numbering in a logical format to describe each of the phasing concepts being considered and discussed in this paper. Although some literature exists on several methods of signal phasing for DDIs, inconsistency in the reporting leaves practitioners scratching their heads when attempting to decipher what phasing scheme to use. In response, three fundamental phasing schemes are presented, one each for volume patterns with two, three, and four critical movements. Each scheme is described with a consistent naming convention, and, when possible, each is manipulated to provide varying coordination strategies. In addition, concepts such as use of actuation and barriers to improve coordination are described, and methods for reducing lost time are introduced. Other supplemental information related to preemption and pedestrians is discussed briefly. In conclusion, practitioners are given some basic guidance on when one phasing scheme may be more appropriate than another. }, number={2557}, journal={TRANSPORTATION RESEARCH RECORD}, author={Cunningham, Christopher and Schroeder, Bastian J. and Phillips, Stacie and Urbanik, Thomas and Warchol, Shannon and Tanaka, Alison}, year={2016}, pages={1–10} }
 @article{vaughan_jagadish_bharadwaj_cunningham_schroeder_hummer_findley_rouphail_2015, title={Long-term monitoring of wrong-way maneuvers at diverging diamond interchanges}, number={2484}, journal={Transportation Research Record}, author={Vaughan, C. and Jagadish, C. and Bharadwaj, S. and Cunningham, C. M. and Schroeder, B. J. and Hummer, J. E. and Findley, D. and Rouphail, N. M.}, year={2015}, pages={129–139} }
 @article{jackson_stolz_cunningham_2015, title={Nonmotorized Site Selection Methods for Continuous and Short-Duration Volume Counting}, ISSN={["2169-4052"]}, DOI={10.3141/2527-06}, abstractNote={ This paper outlines the process for selecting sites to perform counts on transportation facilities in the context of establishing a nonmotorized traffic volume counting program. Many agencies are well practiced in collecting motor vehicle traffic counts and estimating annual average daily traffic volumes for motor vehicles on the basis of knowledge founded on years of research and experience. Selecting sites is one component of developing a consistent system for quantifying nonmotorized travel so bicycle and pedestrian volumes can ultimately feed into tools to measure existing trends and model future increases in nonmotorized trips at site, corridor, and regional levels. The outcome of collecting count data can ultimately assist in evaluating facility usage over time, better inform the project prioritization process, and provide evidence to support nonmotorized facility inclusion through Complete Streets planning and improve planning for active transportation. This paper outlines the goals of a nonmotorized traffic monitoring program and objectives of the site selection process. From the experience of a pilot project conducted by the North Carolina Department of Transportation, the site selection method details the following components: gathering potential sites, conducting a site visit, gathering additional data needed to inform the decision-making process, and ultimately selecting sites and developing an equipment inventory. }, number={2527}, journal={TRANSPORTATION RESEARCH RECORD}, author={Jackson, Kristy N. and Stolz, Elizabeth and Cunningham, Christopher}, year={2015}, pages={49–57} }
 @article{holzem_hummer_cunningham_o'brien_schroeder_salamati_2015, title={Pedestrian and bicyclist accommodations and crossings on superstreets}, number={2486}, journal={Transportation Research Record}, author={Holzem, A. M. and Hummer, J. E. and Cunningham, C. M. and O'Brien, S. W. and Schroeder, B. J. and Salamati, K.}, year={2015}, pages={37–44} }
 @article{ott_fiedler_hummer_foyle_cunningham_2015, title={Resident, Commuter, and Business Perceptions of New Superstreets}, volume={141}, ISSN={["1943-5436"]}, DOI={10.1061/(asce)te.1943-5436.0000754}, abstractNote={AbstractSuperstreets are an unconventional at-grade intersection design that have significant potential to help with safety and delay. The purpose of this paper is to formally evaluate residential, commuter, and business owner opinions of superstreets across North Carolina through feedback from three separate surveys. Findings from each of the surveys provide interesting feedback. Residents living near superstreets agree the design helps them travel more safely through the intersection. Commuting drivers perceive superstreets to be more difficult to navigate, but feel strongly about savings in travel time and reductions in numbers of stopped vehicles. Business reactions varied greatly depending on the ability to make direct left turns from the arterial. In general, more business managers feel superstreets negatively impact business growth and operations. Based on the opinions of adjacent business owners/managers, access and confusion were identified as key problems in retaining the number of regular custo...}, number={7}, journal={JOURNAL OF TRANSPORTATION ENGINEERING}, author={Ott, Sarah E. and Fiedler, Rebecca L. and Hummer, Joseph E. and Foyle, Robert S. and Cunningham, Christopher M.}, year={2015}, month={Jul} }
 @article{chang_findley_cunningham_tsai_2014, title={Considerations for Effective Lidar Deployment by Transportation Agencies}, ISSN={["2169-4052"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000348890600001&KeyUID=WOS:000348890600001}, DOI={10.3141/2440-01}, abstractNote={ Lidar is becoming increasingly popular across the United States, and state transportation agencies are adopting this technology for practical uses in transportation-related applications. This trend can be seen in the growing number of agencies acquiring lidar scanners and contracting lidar services. The primary factors behind this trend are that (a) surveyors, engineers, and technicians are becoming more educated about and increasingly open to lidar and its applications and (b) lidar is potentially more cost-effective than traditional surveying technologies. Lidar can provide transportation agencies with the benefits of safety, data collection productivity, cost-effectiveness, applicability, high levels of detail, and technological advancement. Many of the more practical uses and benefits of lidar have come to fruition in recent years, and transportation agencies have been more open to its use. However, little more than anecdotal evidence supports when a specific lidar platform should be applied for various applications rather than a traditional surveying method. Decision makers in geomatic and surveying departments that use lidar must regularly weigh the options of which surveying method to use for specific projects and base decisions on performance tradeoffs. The methodology presented in this paper aims to provide guidance on how agencies may determine whether lidar can be practically used within their organizations. The aspects and performance measures outlined for effective deployment of lidar equipment or contracted services should be systematically considered. }, number={2440}, journal={TRANSPORTATION RESEARCH RECORD}, publisher={Transportation Research Board, National Research Council}, author={Chang, Jeffrey C. and Findley, Daniel J. and Cunningham, Christopher M. and Tsai, Mary K.}, year={2014}, pages={1–8} }
 @article{yeom_schroeder_cunningham_vaughan_rouphail_hummer_2014, title={Lane utilization at two-lane arterial approaches to double crossover diamond interchanges}, number={2461}, journal={Transportation Research Record}, author={Yeom, C. and Schroeder, B. J. and Cunningham, C. and Vaughan, C. and Rouphail, N. M. and Hummer, J. E.}, year={2014}, pages={103–112} }
 @article{findley_cunningham_chang_hovey_corwin_2013, title={Effects of License Plate Attributes on Automatic License Plate Recognition}, ISSN={["0361-1981"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000323141900006&KeyUID=WOS:000323141900006}, DOI={10.3141/2327-05}, abstractNote={ This paper describes an experiment designed to develop a comprehensive and thorough understanding of the readability of North Carolina's license plates with an automatic license plate recognition system. This research focused on law enforcement applications and used two infrared camera systems for data collection in a controlled environment involving more than 900 license plates. The field test was conducted in a controlled environment under the following settings and conditions: a test vehicle traveling at 25 mph, nighttime evaluation, closed test track, 40 ft of spacing of license plates, 9 ft of lateral offset between the license plates and camera, standard issue and specialty plate types, standard syntax and personalized plates, and various license plate ages and conditions. The key finding of this research project is that the current, standard issue license plate with characters in blue ink has the highest capture and read rates among the plates tested in this study. Factors that decreased the capture and read rates were personalized syntax, specialty license plates, and the presence of stacked characters on a specialty license plate. }, number={2327}, journal={TRANSPORTATION RESEARCH RECORD}, author={Findley, Daniel J. and Cunningham, Christopher M. and Chang, Jeffrey C. and Hovey, Kyle A. and Corwin, Michael A.}, year={2013}, pages={34–44} }
 @misc{cunningham_chang_findley_vaughan_martin_hekele_tatham_2013, title={Public Opinions of Roadway Assets Roadway Review as a New Survey Method}, ISSN={["2169-4052"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000327920200005&KeyUID=WOS:000327920200005}, DOI={10.3141/2361-04}, abstractNote={ In October 2011, the North Carolina Department of Transportation conducted a roadway review with a randomly recruited sample of North Carolina residents and community leaders. More than 300 people from 61 communities participated in the surveys, which were held in six locations: Asheville, Burlington, Charlotte, Jonesville, Rocky Mount, and Wilmington. The purpose of the roadway review was twofold: to determine the expectations for the condition of North Carolina highways and to identify the features that North Carolinians believe are most important on different types of highways. Surveys were completed during both daytime and nighttime hours and covered many roadway maintenance aspects, such as pavement, landscaping and mowing practices, signage, retroreflectivity, and shoulders. Regression equations are also provided to predict the overall satisfaction of condition, safety, and appearance by each individual roadway type. }, number={2361}, journal={TRANSPORTATION RESEARCH RECORD}, author={Cunningham, Christopher M. and Chang, Jeffrey C. and Findley, Daniel J. and Vaughan, Christopher L. and Martin, James and Hekele, Aaron and Tatham, Chris}, year={2013}, pages={25–34} }
 @article{salamati_schroeder_rouphail_cunningham_zhang_kaber_2012, title={Simulator study of driver responses to pedestrian treatments at multilane roundabouts}, number={2312}, journal={Transportation Research Record}, author={Salamati, K. and Schroeder, B. and Rouphail, N. M. and Cunningham, C. and Zhang, Y. and Kaber, D.}, year={2012}, pages={67–75} }
 @article{findley_cunningham_schroeder_vaughan_fowler_2012, title={Structural and safety investigation of statewide performance of weathered steel beam guardrail in North Carolina}, number={2309}, journal={Transportation Research Record}, author={Findley, D. J. and Cunningham, C. M. and Schroeder, B. J. and Vaughan, C. L. and Fowler, T. J.}, year={2012}, pages={63–72} }
 @article{findley_cunningham_hummer_2011, title={Comparison of mobile and manual data collection for roadway components}, volume={19}, ISSN={["0968-090X"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000288637400011&KeyUID=WOS:000288637400011}, DOI={10.1016/j.trc.2010.08.002}, abstractNote={The primary objective of this research effort was to compare roadside data collected by typical manual methods – on foot and often requiring traffic control – to data collected by manned data collection vehicles moving with traffic. The research team provided an unbiased comparison of multiple vendors collecting many types of data on various roadway elements including curb, guardrail, signs, pavement markings, and roadway geometry. These data are frequently collected and used by many units within a highway agency such as roadway maintenance, safety, and operations. The research team provided a catalog to each vendor prior to running a 144.8 km (90-mile) test course. The catalog provided a map of the course, a list of each roadway element to be collected, and specific details on how each data element was collected manually. The test course included a variety of highways across a portion of central North Carolina. Multiple data collection companies were given the opportunity to participate, with six actually agreeing to partake and submit data. No vendors supplied sign retroreflectivity data, one submitted pavement marking retroreflectivity data, three submitted roadway geometry data, and five submitted data on roadside elements. The results showed that mobile data compared reasonably well to manual data for most of the desired variables. Mobile data on elements in close proximity to the edge of pavement matched manual data better than elements further from the road. Counts of specific elements were a better fit between mobile and manual data than elements that needed qualitative judgments. Among the major lessons learned is the need for crystal clear specifications before embarking on a mobile data collection program and the desirability of having vendors submit data for a small sample of roadway before embarking on the bulk of a data collection effort.}, number={3}, journal={TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES}, author={Findley, Daniel J. and Cunningham, Christopher M. and Hummer, Joseph E.}, year={2011}, month={Jun}, pages={521–540} }
 @article{salamati_schroeder_rouphail_cunningham_long_barlow_2011, title={Development and implementation of conflict-based assessment of pedestrian safety to evaluate accessibility of complex intersections}, number={2264}, journal={Transportation Research Record}, author={Salamati, K. and Schroeder, B. and Rouphail, N. M. and Cunningham, C. and Long, R. and Barlow, J.}, year={2011}, pages={148–155} }
 @article{cunningham_schroeder_vaughan_hughes_2011, title={Is ticketing aggressive cars and trucks effective in changing driver behavior? Evidence from North Carolina}, number={2265}, journal={Transportation Research Record}, author={Cunningham, C. M. and Schroeder, B. J. and Vaughan, C. and Hughes, R. G.}, year={2011}, pages={100–108} }
 @article{scott_barlow_guth_bentzen_cunningham_long_2011, title={Nonvisual Cues for Aligning to Cross Streets}, volume={105}, ISSN={["0145-482X"]}, DOI={10.1177/0145482x1110501011}, abstractNote={ Accurately aligning to a crosswalk is an important component of safe street crossing for pedestrians who are blind. Six alignment cues were evaluated in a simulated crosswalk environment in which the angle of the crosswalk was not always in line with the slope of the ramp. The effectiveness of each cue is reported and implications are discussed. }, number={10}, journal={JOURNAL OF VISUAL IMPAIRMENT & BLINDNESS}, author={Scott, Alan C. and Barlow, Janet M. and Guth, David A. and Bentzen, Billie Louise and Cunningham, Christopher M. and Long, Richard}, year={2011}, pages={648–661} }
 @article{haley_ott_hummer_foyle_cunningham_schroeder_2011, title={Operational effects of signalized superstreets in North Carolina}, number={2223}, journal={Transportation Research Record}, author={Haley, R. L. and Ott, S. E. and Hummer, J. E. and Foyle, R. S. and Cunningham, C. M. and Schroeder, B. J.}, year={2011}, pages={72–79} }
 @article{scott_barlow_guth_bentzen_cunningham_long_2011, title={Walking Between the Lines: Nonvisual Cues for Maintaining Headings During Street Crossings}, volume={105}, ISSN={["1559-1476"]}, DOI={10.1177/0145482x1110501012}, abstractNote={ Five cues were evaluated with respect to their usefulness in directing the headings of pedestrians who were blind during street crossings. The study was conducted at a simulated crosswalk, with the angle of the crosswalk varied relative to the approach and direction of the slope of the ramp. Three cues worked well over the distance equivalent to the width of a six-lane road. }, number={10}, journal={JOURNAL OF VISUAL IMPAIRMENT & BLINDNESS}, author={Scott, Alan C. and Barlow, Janet M. and Guth, David A. and Bentzen, Billie Louise and Cunningham, Christopher M. and Long, Richard}, year={2011}, pages={662–674} }
 @article{cunningham_hummer_moon_2008, title={Analysis of Automated Speed Enforcement Cameras in Charlotte, North Carolina}, ISSN={["2169-4052"]}, DOI={10.3141/2078-17}, abstractNote={ The effects of a mobile automated speed enforcement system in Charlotte, North Carolina, were examined. Limited focus groups were conducted to characterize resident and professional attitudes, opinions, and beliefs regarding such a speed program. Overall, opinions were positive. The system, consisting of three mobile units, was implemented along 14 corridors. Two separate analyses were conducted on data collected from January 2000 to December 2005. Findings from a previous study done for the North Carolina Governor's Highway Safety Program were updated. The first, and primary, analysis was a before-and-after analysis of collisions. This study used Hauer's comparison group methodology. Three different collision data sets were analyzed: total collisions, data accounting for regression to the mean, and data for five heavily enforced corridors. On the basis of the analysis, the impact of regression to the mean appears to be negligible. The results indicate that the camera program likely reduced collisions in corridors with automated enforcement. The second analysis observed whether compliance with posted speed limits was enhanced. Mean speeds, median speeds, 85th percentile speeds, and percentages of drivers more than 10 mph over the speed limit were analyzed. The analyses found speed reductions caused by the camera program. On the basis of these findings, it was recommend that the City of Charlotte continue the automated speed enforcement program. Other agencies considering speed camera programs can benefit from the knowledge gained in Charlotte. }, number={2078}, journal={TRANSPORTATION RESEARCH RECORD}, author={Cunningham, Christopher M. and Hummer, Joseph E. and Moon, Jae-Pil}, year={2008}, pages={127–134} }
 @inbook{baek_hummer_williams_cunningham_2006, title={Reasonable speed limits on suburban multilane highways with curbs}, ISBN={0309099781}, number={1969}, booktitle={Highway safety: law enforcement; alcohol; driver training; safety planning and management; commercial vehicles; and motorcycles}, publisher={Washington: Transportation Research Board Natl Research Council}, author={Baek, J. and Hummer, J. E. and Williams, B. M. and Cunningham, C. M.}, year={2006}, pages={10–17} }