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Passenger car equivalency (PCE) has been used for decades to convert mixed vehicle traffic into equivalent pure passenger car traffic streams for transportation planning, design, and operational analysis purposes. The term PCE was defined by the Highway Capacity Manual (HCM) in 1965 as an adjustment factor, and many approaches have continued to be developed for refining PCE values for different types of freeway geometry and vehicle distributions since then. This paper proposes an improved data-driven state-dependent passenger car equivalency (PCE–SD) approach, initially for level terrain basic freeway segments that consider average vehicle lengths for different types of vehicles. The term “state-dependent” refers to the space headway ratio at the same speed ranges between long vehicles (trucks), that fall into the same clustered category, and passenger cars. The relatively unique data stream used in this study comes from the Portland Oregon Regional Transportation Archive Listing (PORTAL) online datahub. This rich continuous data stream provides valuable information about traffic-related data at a 20-s aggregation level. Most importantly for this effort, ranges of categorical vehicle lengths are also available. According to analysis results, PCE–SD values estimate the actual passenger car distribution at different speeds and levels of operational performance (levels of service) more accurately compared with the HCM-6 PCEs on level terrain basic freeway segments. The authors propose that a state-dependent passenger car equivalency approach bridges the conversion gap from different types of trucks to passenger vehicles and could be used as an improved supplementary methodology.

Bikeshare provides important first mile–last mile, commuting, circulation, and sightseeing options in many cities. Bikeshare can also be healthy and convenient for users. Throughout the year, holidays occur that change typical bikeshare activity patterns. Existing literature shows mixed results relating to the ridership impacts of holidays: some research shows that these days may result in higher ridership, whereas others show no effect. Because of variations in system locations and modeling methods, it is difficult to determine the reasons for these mixed results. To control for these aspects, this project consisted of a multicity study of the effect of holidays on system-level ridership using a loglinear regression model with robust standard errors. The results showed the impacts of holidays on bikeshare system ridership for different user types among systems in the Washington D.C., Chicago, Boston, Los Angeles, and Minneapolis metro areas. Several hypotheses were developed and tested to examine the effects of holidays on bikeshare usage. A major finding from this study was that federal holidays negatively affected member ridership and positively affected nonmember ridership. It was also found that different federal holidays had dissimilar effects on total ridership. These findings could be useful for bikeshare agencies to plan, reposition fleet, and improve system operation.

Traffic features were investigated for a bottleneck that was observed on a 30 mi northbound section of Florida’s Turnpike (SR-91) during the mass evacuation in advance of Hurricane Irma that occurred in September 2017. Radar detector data (at 1 min intervals) from the Regional Integrated Transportation Information System were utilized to determine the periods when a bottleneck was active adjacent to a service plaza along the roadway. Three distinct time periods were identified during which a bottleneck was active at the service plaza off-ramp, for a total of 27.5 h during the evacuation period. To identify and confirm each bottleneck activation and duration, and to measure the traffic flow features that characterized the bottleneck, curves of cumulative vehicle count and occupancy were utilized. Analysis of these curves revealed time periods during which excess vehicle accumulation and delay occurred between successive detector stations along the Turnpike. Results demonstrate distinct queued and free flowing traffic states between adjacent detectors in the vicinity of an off-ramp into a service plaza. The apparent bottleneck discharge features presented substantially lower flows than what would be expected for a limited access facility with high operational speeds. Findings from this paper present important considerations for evacuation planning and modeling as roadway traffic features may only present themselves during evacuations and if not accounted for may drastically reduce the precision of models and simulations.

Background The vascular access represents a crucial phase in the management of complications related to the implantation of devices. After the use of the axillary vein, which allows the elimination of intrathoracic complications as well as the subclavian crush of the catheters, the ultrasound–guided approach could represent the next step for the reduction of vascular complications. Experience All implants performed (n = 86) by an independent operator who implemented ultrasound to minimize complications related to central access were reviewed. During the first phase, the ultrasound–guided approach involved the study of vascular accesses before the start of the implant. The assessment took place before the preparation of the sterile field, for the localization of the axillary approach and for the study of the anatomical variants. It was immediately followed by the use of skin marks. The use of markers made it possible to attempt surgical isolation of the cephalic vein as a first approach. In case of failure, or the need for multiple accesses, the transition to central access could be facilitated by the presence of skin markers. This approach have not significantly modified the probability of successful axillary vein puncture without the use of venography (75% vs 71%, p NS). In the last phase all implants were performed with ultrasound–guided puncture with sterile technique before skin incision (n = 26). The procedures involved dual chamber (61%), single chamber (19%), CRTD (11%), dual chamber ICD. Ultrasound showed all cases of hypoplastic cephalic vein (15%). In the first three months of implementation, the success rate was 71.4% with 1 self–healing case of apical pneumothorax. In the following months the success rate rapidly increased to 94.1% (p Conclusions The ultrasound study of the accesses performed before the incision allows to identify the anatomy and to define the course of the axillary vascular system and its relationships. When performed with a sterile approach, it allows direct ultrasound–guided puncture before the surgical incision, with a high success rate from the early stages of implementation.

Background The Italian National Healthcare Outcomes Program (PNE – AGENAS) each year provides quality performance measures for our Hospitals. Some measures refer directly to hard events such as mortality, others are focused over procedures that should be related to subsequent events, including mortality. The rate of PCI performed within 48 hours (48h–PCI) in patients with acute myocardial infarction (AMI) is currently used as a performance measures. An arbitrary standard of 35–40% of 48h–PCI for patients with AMI is considered the goal for a satisfactory practice. Methods We analyzed the PNE–AGENAS performance measures for the year 2020. Overall 1652 MI have been recorded in 2020 in Tuscany. We considered those Hospitals with > 100 AMI. We related the 30 day and one–year mortality with the 48h–PCI of the 20 Hospitals identified. Of these latter 13 are Hospitals with a 24h PCI service. Results All the hospitals hosting a catheterization laboratory largely overcame the 48h–PCI quality standard although with a wide variation among sites (70,8 – 90.4%). On the contrary all the Hospitals without a cath–lab did not even approach the standard (0–33.%). The analysis of the mortality data both at 30 day and at 1 year showed a wide variability among Hospitals without an appreciable difference. The 30–day mortality rate ranged from 2 to 15% without any relationship with the 48h–PCI. In some cases better survival rates were recorded for those Hospitals with the worse 48h–PCI. Conclusions Several factors makes 48h–PCI a useless and even confounding measure of performance. As a matter of fact this measure does not consider the type of MI treated (STEMI vs NSTEMI), nor the presence or not of a cath lab. Also it does not take account for the case mix of the population of AMI treated. Patients with STEMI represents about 30% of the activity of an Hospital with a 24h cath –lab. It is obviously easy for such an Hospital to satisfy the proposed standard as these patients should receive their PCI well before 24 hours. The contemporary organizations do cooperate and are organized as networks. The 48h–PCI should be only used to evaluate these networks, not the single hospitals. In conclusion our analysis by showing the divergent and paradoxical phenomena of better or similar survival in spite of longer or similar 48hPCI highlights the need to abandon this useless and even confounding measure to evaluate the Cardiology practice in the Italian Hospital.

Besides elevated temperature applications, Inconel 718 is widely chosen for components subjected to heavy loads operating in aggressive environments, which can promote the production of hydrogen on the metal surface. Selective Laser Melting (SLM) is an emerging technology for the production of structural components in Inconel 718 or Inconel 625 alloys, allowing to create functionally optimized shapes and overcome the traditional manufacturing limitations. However, the SLM process introduces a peculiar microstructure and severe residual stresses that can affect hydrogen migration and accumulation. While the mechanical properties were deeply investigated in recent years, the resistance of SLMed Inconel 718 to the Hydrogen Embrittlement (HE) is still an open issue. The present work deals with a preliminary assessment of the hydrogen embrittlement susceptibility of the SLMed In718 in the as-built condition. Slow strain rate tests were carried out on unnotched specimens that were pre-charged by electrochemical cathodic charging. Fractographic analyses, carried out with a Scanning Electron Microscope (SEM), were used to identify the effects produced by the hydrogen intake on the material microstructure. The material resulted to be susceptible to hydrogen embrittlement, featuring a significant ductility reduction in presence of extremely elevated hydrogen concentrations. The hydrogen content was measured by employing the Hot Extraction Method (HEM), for each mechanical test. Due to a low diffusivity value, hydrogen penetrates only within a thin external layer of the specimen. Therefore, to identify the concentration profile, the effective hydrogen diffusion coefficient was identified and the hydrogen diffusion was simulated using Fick’s equation. The loss in mechanical resistance was then correlated to the hydrogen concentration near the fracture onset.

We aim to observationally and statistically constrain the influence of flybys in the formation and evolution of debris disks. We compiled a sample of 254 debris disks with ages between 2 Myr and 8 Gyr that are either part of an association or isolated, drawing the binary and planetary companions of the systems mainly from the literature. Using the Gaia eDR3 astrometric data and radial velocities of our sample, as well as all the sources in a specific region of the sky, we reconstructed the relative linear motions in the last 5 Myr and made predictions for the next 2 Myr. Relating the Hill radius of each debris disk system and the closest distances reached by the two sources, we defined the flyby events in terms of position and time. We find that in the period between the last 5 Myrs and the next 2 Myrs, 90% of the analyzed systems have experienced at least a close flyby, while 7% of them have experienced flybys at distances greater than 0.5R Hill. In particular, 75% of them have experienced at least one past close encounter and 36% multiple past close encounters. From the sub-sample of resolved debris disk (41 out of 94), 80% of the analyzed systems experience at least an encounter within 0.8 pc. From the subsample of 10 debris disks with planets, half of these systems do show misalignments between disk and planet, stirring, or asymmetries. Systems with a misalignment between the planetary orbit and the disk do indeed experience at least one flyby event. In particular, when the planet orbits have a difference with the disk inclination higher than about 20 degree, as in the case of HD 38529, we find that multiple close encounters have taken place in the last 5 Myr, as theoretically predicted. The high incidence of encounters, particularly close encounters, experienced by the systems in the last 5 Myr suggests the fundamental impact of flybys on the evolution of debris disks., Comment: 9 pages, 2 figures

Congestion in bicycle traffic is a daily occurrence at many urban intersections. It is known that a higher density in the queue leads to a higher discharge rate. In theory, higher jam densities than those currently observed in practice are feasible. This leads to our hypothesis that the delay at intersections can be further reduced when cyclists are encouraged to queue up closer together. To explore this option, we carried out an experiment in which the queue configuration was influenced to increase the jam density. This paper presents ways to increase the queuing density, up to twice the density found without instructions. Results show that increasing the jam density does indeed increase the queue discharge rate; this also holds for jam density values that exceed those observed in normal queuing conditions. The efficiency of the queue discharge process, captured by the discharge rate, was found to increase by 40% when cyclists queue up closely together. Qualitative comparison of the queuing positions and discharge patterns showed that the discharge sequence is largely determined by the queuing position, and that cyclists keep a distance from each other in both time and space during the queue discharge phase. When applied in practice, these findings can be used to update the signal length and green phases for all traffic, thereby reducing congestion in urban areas.

Analyzing and visualizing traffic data in order to better understand congestion trends, safety concerns, goods movement and capacity needs is a pressing need. Broadly speaking, there is a large amount of traffic data available today, including volume, lane occupancy, speed, and travel time, which can be used to manage transportation networks, provide traveler information and produce performance measures. This broadly disseminated data almost always treats all vehicles alike, without discriminating between trucks and passenger cars. Since trucks are critical and growing components of freeway traffic, monitoring and tracking their dynamics can reveal the impacts of freight movement on current freeway operations and over time will uncover trends useful for future planning and management. This study takes advantage of a unique data stream available for the freeway network of Portland, Oregon, USA. In addition to providing continuous vehicle count, speed and lane occupancies at 20-second intervals at more than 500 stations (1,300 individual detectors), the Portland system reports volume bins at 4 length-based classifications. ( 60 ft). Given that most vehicle classification studies are done over very short time intervals at an extremely limited number of locations, this nonstop data stream enables unprecedented insight into where and when trucks are traveling on Portland’s freeways and a wealth of opportunities for performance measurement and diagnosis of their impacts. The objective of this paper is to exploit this new data stream and explore new visualization techniques that depict truck volume, truck percentage and volume-weighted average vehicle speeds along Portland’s Interstate 5 corridor, an important north-south freight route between the Canada and Mexico borders. Results confirm the merit in analyzing and tracking truck volumes, proportions, and other dynamics for traffic management, information and modeling. The results of this study and the techniques employed here can be used to better understand and visualize freight movement dynamics on a continuous basis.

In a fully connected traffic environment with automated vehicles, new traffic control strategies could replace traditional traffic signals at intersections. In recent years, several studies about reservation-based intersection control strategies have been published, and a significant increase in capacity was shown. In the strategies presented so far, other road users usually play a minor role or are not considered at all. However, many use cases of automated driving occur in urban environments, where pedestrians and bicyclists play a major role. In this paper, a novel strategy for integrating pedestrians into automated intersection management is introduced and compared with a fully actuated traffic (AT) signal control. The presented control consists of a first-come, first-served strategy for vehicles in combination with an on-demand traffic signal for pedestrians. The proposed intersection control is explained, implemented, and tested on a four-leg intersection with several lanes coming from each direction. It dynamically assigns vehicles to lanes, and vehicles follow a protocol that enables cooperative lane-changing on the approach to the intersection. Demand-responsive pedestrian phases are included in such a way that predefined maximum pedestrian waiting times are not exceeded. A set of demand scenarios is simulated using a microsimulation platform. The evaluation shows that the presented control performs significantly better than the AT control when considering low, medium, and high traffic demand. Pedestrian waiting times are slightly improved and at the same time vehicle delays are substantially decreased. However, the control needs to be improved for scenarios with a very high vehicle demand.

Context To enable human mobility, economic vitality, and population well-being in growing cities, well-planned transportation infrastructure is essential. However, transportation systems can also have detrimental impacts on health and equity, including through increased air pollution and its unequal social distribution. Aims This study focuses on estimating air quality and equity impacts of an ongoing large-scale metropolitan transportation program (known as “Tampa Bay Next”). Our objective was to characterize and quantify the air pollution levels and population exposures resulting from an interstate freeway expansion planned under Tampa Bay Next, which includes added toll lanes. Methods We estimated changes in individual human exposures to oxides of nitrogen (NOx) due to the proposed freeway changes, using an integrated suite of high-resolution models for travel demand, emissions, pollutant dispersion, and exposure. Inequity in the distribution of exposures among racioethnic and income groups was also estimated using a few measures of inequality (the subgroup inequality index (SII), the comparative environmental risk index, and the toxic demographic quotient index). Findings The planned freeway expansion was estimated to slightly decrease the daily NOx emissions (by 5.6 mg/m, p = 4×10−16), ambient concentrations (by 0.02 μg/m3, p = 2×10−4), and individual exposures (by 0.2 μg/m3, p = 2.2×10−16) on average, while increasing exposure densities during peak periods in areas surrounding downtown Tampa. Group-average exposures also decreased for all population subgroups under the planned expansion scenario. However, disparities in exposure increased for the black (ΔSII = 1.3×10−3 for the 90th percentile exposure level) and the below-poverty (ΔSII = 4.6×10−3) groups. Conclusions Results suggest that a detailed analysis of exposures may be needed to ensure large-scale transportation improvement programs reduce inequity, even when average impacts on air quality and exposures are positive or neutral.

This paper analyzes temporal and spatial traffic patterns and assesses the performance of Florida roadways during the evacuation for Hurricane Irma (2017). Evacuation-specific performance metrics are used to characterize the performance of the roadway systems and granular analyses are conducted using RITIS probe detector data supplemented with hourly continuous counts from Florida Traffic Online. Results from this study show the disparate nature of roadway utilization during mass evacuations – while most interstates remained congested during the major evacuation period, several other highways remained underutilized, potentially due to the lack of information on roadway conditions during evacuation. On the other hand, certain roadways that were typically underutilized suffered from severe congestion and bottlenecking during the evacuation. Detail-oriented studies of this nature could serve as an important baseline to benefit future emergency and disaster planning, and traffic managements during future events of similar nature.

To build on a project recently completed for the Oregon Department of Transportation (DOT), processes and tools were developed to prioritize the implementation of connected vehicle (CV) applications. Internal mechanisms for addressing CV development and deployment at the Oregon DOT were assessed; the technical maturity of each potential CV application was scanned, reviewed, and assessed; preliminary goals were developed; prospective CV applications were linked; and applications that fit with the potential role of the Oregon DOT in advancing these initiatives were refined, prioritized, and ranked. A shared vision and business plan that prioritizes CV applications for Oregon is recommended. An internal effort aimed at producing a small set of priority CV applications for further development is described. This effort culminated in a CV application prioritization workshop that included a priority mapping exercise, discussion of the CV concept, and an initial mapping of goals and applications. The workshop identified seven near-term priority CV applications for the Oregon DOT; 12 applications that the Oregon DOT will monitor (and possibly collaborate on with others in the future); and eight applications that the Oregon DOT will monitor but that will be led by others. The Oregon DOT has used the results of this effort as a springboard for hiring new staff dedicated to CV policy, forming a CV steering team, and launching a CV business plan. The process and tools can be used by other states and transportation agencies in their CV application prioritization processes.

What do we already know about this subject? • Chronic pain can have negative effects on quality of life. It is associated with a reduced ability to work, quality of life and disability, conditions that should be treated in specialized pain management clinics. In Italy very little information on clinical outcomes after chronic pain treatments is provided. What does our study add to the already existing information • This study is the first to provide clinical data about the impact of chronic pain in terms of quality of life and disability on patients who attended pain management clinics in Italy. • Chronic pain has a negative impact on quality of life and disability and causes presenteeism. • Statistical significant results in pain management do not often correspond to best results in clinical settings

From the time and money lost sitting in congestion and waiting for traffic signals to change, to the many people injured and killed in traffic crashes each year, to the emissions and energy consumption from our vehicles, the effects of transportation on our daily lives are immense. A wealth of transportation data is available to help address these problems; from data from sensors installed to monitor and operate the roadways and traffic signals to data from cell phone apps and -- just over the horizon -- data from connected vehicles and infrastructure. However, this wealth of data has yet to be effectively leveraged, thus providing opportunities in areas such as improving traffic safety, reducing congestion, improving traffic signal timing, personalizing routing, coordinating across transportation agencies and more. This paper presents opportunities and challenges in applying data management technology to the transportation domain.

Active traffic management (ATM) systems are becoming increasingly important, particularly in urban areas aiming to combat recurrent and nonrecurrent congestion. ATM systems apply proactive strategies to improve safety and mobility, as well as to reduce emissions, noise, and fuel consumption. As one of the key elements in the ATM toolbox, variable speed limit (VSL) systems are being increasingly deployed around the United States. In the past, most VSL systems in Europe have included automated enforcement as part of the system, while systems in the United States have relied on traditional speed enforcement strategies. In the Portland, Oregon, metropolitan area, a new traffic- and weather-responsive VSL system has been deployed. It uses variable advisory speeds (VAS), allowing law enforcement to rely on the basic rule for enforcement. Thanks to the availability of high-resolution intelligent transportation systems data, it is possible to conduct post hoc analysis after VSL deployments. This paper focuses on driver compliance with displayed VAS messages. “Compliance” is defined as the difference between the displayed speed and the measured speed of traffic. In addition to analyzing more than 35 days at the Portland site, for comparison purposes, some additional analysis of a VSL site in Munich, Germany, is also included. The analysis of compliance for VSL–VAS deployments is useful for understanding the benefits of these important ATM strategies, assisting with targeting enforcement actions, and better understanding where and when to employ VSL–VAS systems.

After several decades of advances, simulation has become an important tool in the modeling of transportation systems and is widely applied in practice. Guides have been created by organizations in several countries, and dozens of papers have been published in scientific journals on the theory and application of transport simulation; these works are aimed at guiding practitioners in the use of simulation tools. However, transport simulation still lacks a unified and comprehensive guide for use in practice. The lack of such a document leads to conflicts between modelers, agencies, and decision makers and allows inappropriate use of the models. The outcome is often inaccurate results, inefficient use of resources, and conflict. This paper reviews and analyzes the existing transportation simulation guides. It identifies gaps and limitations and proposes an outline for a comprehensive simulation manual that is based on stakeholder input. Review of the existing guidance documents reveals that almost all these documents focus on traffic operations, and they provide either broad guidelines for building simulation models or advice on using a specific software product. Other issues, particularly those related to topics such as safety assessments, environmental impacts, public transportation, pedestrians, bicycles, simulation algorithms, agent-based simulation, and multimodal simulation, are addressed in only a cursory fashion. This paper proposes a possible structure for a transportation system simulation manual that would cover the limitations and gaps in the existing literature. The proposed document would consist of five volumes: concepts, model building, verification and validation, results analysis, and case studies and supplementary materials.

Advanced traveler information system (ATIS) has been used and is viewed as an essential component for present-day traffic management. ATIS may provide information such as the traffic situation, incidents, and weather conditions which may adversely affect traffic. This information may be disseminated through media such as dynamic navigation devices and the variable speed limit (VSL) systems. The objective of this study was to examine whether there exist inconsistency in traffic information provided from different sources. The VSL and data for real-time traffic information (RTTI) for navigation systems were used as subjects for the study. The assessment was made by comparing the discretized space-time representation of ground truth (GT) speeds, reconstructed from inductive loop detector data, to the space-time traffic information displayed by the VSL or the navigation system. The discretization ensured that the method takes into consideration, limitations faced by the providers in broadcasting the information. The VSL system and data for navigation systems obtained from a private provider on the Autobahn A99, near Munich, were used as case study.

Variable speed limit (VSL) control systems have been used as a link control scheme on freeways and urban arterial roads. VSL systems aim to provide advance warning, to harmonize traffic speeds, or to accomplish both. The objective of this paper is to develop methods for assessing the harmonization potential of VSL systems. Two approaches based on the ability of the system to reduce inhomogeneity in the traffic stream and improve the consistency (proper coordination) of the displayed speed limits are presented. Inhomogeneity in the traffic stream was checked by first identifying the traffic state and assessing the ability of the system to reduce the speed differential in the metastable traffic state (i.e., flows > free flow but with speeds > congestion speed). The coefficient of variation was used to quantify the standard deviation of speed. Consistency was assessed by observing the consecutive dynamic changes in the displayed speed limits as drivers traverse the route. This assessment was done by reconstructing the traffic state from loop detector data, generating virtual trajectories based on the reconstruction, and finally tracking the virtual vehicles to reproduce the sequence of speed limits that drivers would have experienced. The methods developed were tested for the VSL system on the Autobahn 99 near Munich, Germany.

As connected vehicle (CV) research moves into deployment, metropolitan planning organizations; state, local, and transit agencies; and the private sector will start experiencing the effects of vehicles, aftermarket devices, mobile devices, and infrastructure with dedicated short-range wireless communications and other wireless connectivity at their cores. Like other states and regions, the Oregon Department of Transportation (DOT) could benefit from the preliminary scoping, evaluation, and assessment of the impact of CVs and infrastructure and a wide range of potential cooperative system applications. With this in mind, the Oregon DOT is determining whether to pursue the next phases of federal funding for CV applications. The Oregon DOT also wants to make an informed choice about taking a national leadership role in the CV arena and to assess opportunities to join projects with other partners. This paper describes the empirical results of a survey that, to assist the Oregon DOT in its assessment, was distributed to agency staff to gauge the perception of CV and automated vehicle (AV) technology. Most respondents had heard of this technology and were in favor of its application. However, many respondents had concerns about cybersecurity and the catastrophic consequences of system failure, and many respondents voiced concerns about the Oregon DOT’s preparedness for CVs or AVs. The Oregon DOT and other agencies can use these findings to help prepare for a better future with CVs and AVs.

The first variable advisory speed (VAS) system in Portland, Oregon, was recently installed on OR-217. This system, designed to be responsive to both congestion and weather, was installed to address issues along the corridor, including unreliable travel times, high crash rates, and substantial declines in performance during adverse weather. To assess the merits and effectiveness of the VAS system, a before and after analysis of corridor performance in terms of capacity, reliability, and safety is being conducted. This paper summarizes the findings of the before analysis and presents results from the after analysis during the first 9 months of operation. Before the system’s activation, OR-217 suffered from highly variable travel times, frequent severe bottlenecks, a high rate of rear-end collisions, and significant speed differentials between adjacent lanes. Though the system was activated in the summer of 2014 and the system’s long-term effects are not yet definitely established, some notable evidence of travel time reliability improvements has already been documented. The system’s safety impacts will be the subject of ongoing analysis.

Variable Speed Limit (VSL) and Variable Advisory Speed (VAS) systems are applications of a growing field of active traffic management systems (ATM). This technology aims to improve safety while reducing congestion and emissions. VSL is common on German freeways, harmonizing traffic flow during congestion and weather events. Portland, Oregon installed a VAS system (advisory meaning it is not automatically enforced) on an eleven km (7 mile) segment of heavily congested urban freeway. The Portland region maintains archived, high-resolution data of both VAS sign messages and speed detection loop feedback, permitting reconstruction of traffic and sign data. This work analyses over 30 days of archived data from the Portland site in order to study driver compliance to the VAS signs. The focus is to suggest methods and parameters to score system performance. Such an analysis could benefit new rollouts of VAS corridors by providing system performance feedback and shed light on options for improving system performance.

Safety remains a problem on U.S. roadways, with more than 32,000 fatalities, 2.2 million injuries and 6 million crashes each year. Travelers, shippers and the economy are exposed to increasing amounts of congestion, unreliability, delay, emissions and excess energy consumption, which impede the efficient movement of people and goods. The U.S. Department of Transportation (DOT) had embarked upon a major research program toward implementing connected vehicle safety technologies, applications and systems using dedicated, short-range wireless communications (DSRC). Previous research by the National Highway Traffic Safety Administration (NHTSA) demonstrated that 80% of unimpaired driver crash types could be addressed by the connected vehicle technology. Through the year-long Safety Pilot that took place in Michigan from 2012 to 2013, U.S. DOT tested the effectiveness of wireless connected vehicle technology in real-world, multimodal driving conditions; collecting data about how ordinary drivers adapt to the use of connected vehicle technology; and identifying the potential safety benefits of connected vehicle technology. This work was performed in recognition of a February 3, 2014 NHTSA agency decision for light vehicles and a similar decision expected soon for commercial vehicles that will likely launch regulatory processes to require or incentivize all new vehicles to be equipped with DSRC devices. Communication among and between vehicles and the infrastructure (including traffic signals, work zone equipment, or pavement sensors, and other infrastructure elements) would also have data and mobility benefits (including data-driven applications such as traveler information for freight and passengers, transit operations, network flow optimization, traffic signal systems and incident response, emergency staging, and evacuation as well as sustainability-related applications). This paper describes an ongoing effort to explore opportunities for the state of Oregon, USA, to participate in future funded pilot deployments of mobility and environmental related applications in the coming years—possibly including a set of regional pilots as well as smaller, more self-contained projects focused on priority applications. As connected vehicle research moves into deployment, state, local and transit agencies, Metropolitan Planning Organizations and the private sector will start experiencing the effects of vehicles, after-market devices, mobile devices, and infrastructure with DSRC and other wireless connectivity at their cores. Along with other states and regions, the Oregon Department of Transportation (ODOT) can benefit from preliminary scoping, evaluation, and assessment of the impact of connected vehicles and infrastructure and a wide range of potential cooperative system applications. With this in mind, ODOT can determine whether or not to pursue the next phases of federal connected vehicle application funding. It can also make an informed choice about taking a potential national leadership role in the connected vehicle arena, and assess opportunities to join projects with other partners. This paper provides a summary of an internal survey conducted within ODOT along with insights gained from the analysis of the survey results. Next steps in the process are also described.

Travel time and operating speed influence the attractiveness, operating cost, and system efficiency of transit service. As part of its bus dispatch system, the Tri-County Metropolitan Transportation District of Oregon has been archiving automatic vehicle location (AVL) and automatic passenger count data for all bus trips at the stop level since 1997. In 2013, a new and higher-resolution bus AVL data collection system was implemented. This new system provides stop-level data as well as 5-s resolution (5-SR) bus position data between stops. The objective of this paper is to explore potential applications of the new data for assessing transit performance and for estimating transportation system performance measures for urban arterials. Results suggest that the 5-SR data provide high-resolution information on time and position that can be used to determine bus travel speeds between bus stops, identify speed breakdowns, and estimate intersection signal and queuing delays.