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Traffic congestion is one key factor that delays emergency supply logistics after disasters, but it is seldom explicitly considered in previous emergency supply planning models. To fill the gap, we incorporate traffic congestion effects and propose a two-stage location-allocation model that facilitates the planning of emergency supplies pre-positioning and post-disaster transportation. The formulated mixed-integer nonlinear programming model is solved by applying the generalized Benders decomposition algorithm, and the suggested approach outperforms the direct solving strategy. With a case study on a hurricane threat in the southeastern USA, we illustrate that our traffic congestion incorporated model is a meaningful generalization of a previous emergency supply planning model in the literature. Finally, managerial insights about the supplies pre-positioning plan and traffic control policy are discussed. [ABSTRACT FROM AUTHOR]

Problem, research strategy, and findings: Planners commonly recommend compact development in part as a way of getting people to drive less, with the idea that less driving will lead to more sustainable communities. Planners base their recommendations on a substantial body of research that examines the impact of compact development on driving. Different studies, however, have found different outcomes: Some studies find that compact development causes people to drive less, while other studies do not. I use meta-regression analysis to a) explain why different studies on driving and compact development yield different results, and b) combine different findings from many studies into reliable statistics that can better inform planning practice. I address the following questions: Does compact development make people drive less, and if so, how much less? I find that compact development does make people drive less, because most of the compact development features I study have a statistically significant negative influence on driving. The impact, however, is fairly small: Compact development features do not appear to have much influence on driving. My findings are limited to some extent because they are derived from small sample sizes. Takeaway for practice: Planners should not rely on compact development as their only strategy for reducing driving unless their goals for reduced driving are very modest and can be achieved at a low cost. [ABSTRACT FROM PUBLISHER]

In this study, 20-year and 40-year designs of common pavement types in USA at three traffic levels are examined for their environmental burdens, including hot mix asphalt pavement, jointed plain concrete pavement and continuously reinforced concrete pavement. The study first introduced a previously built life cycle assessment model in pavement engineering and then performed the detailed modelling for each pavement design, with special efforts devoting to the delay estimation of in the congestion module and the usage module (roughness effect on the fuel economy). In the context of this study, regarding the multiple environmental indicators, it is found that 40-year pavement designs do not necessarily carry environmental advantages over their 20-year counterparts, being only possible at ‘high’ traffic volumes. Sensitivity analysis indicates that the influences of stress developing rate, recycling, feedstock energy of asphalt binder and maintenance strategy are less significant compared to that of traffic volume. In the life cycle inventory, material module and usage module are two dominating contributors; share of congestion module due to construction and maintenance activities grows quickly with the increase of traffic volume. [ABSTRACT FROM AUTHOR]

This research considers the implications of building places that possess many of the qualities that make New Urbanism so desirable but also marginalizing them with other qualities that prioritize automobility to meet the demands of conventional traffic engineering standards. By examining the existing built environment of Stapleton – a New Urbanist development in Denver, Colorado – in terms of street network characteristics, street designs, and intersection designs, I investigate the inconsistencies of the resulting built environment with respect to the latest research and state-of-the-practice New Urbanism design ideals. The outcomes are then considered in terms of how people actually use the transportation system by way of vehicle speed studies and travel diaries. The trends suggest that mixing New Urbanist neighborhood and street design characteristics with conventional traffic engineering standards results in travel behaviors more consistent with conventional auto-oriented developments. [ABSTRACT FROM PUBLISHER]

Background:Seat belt use in the United States increased from 11 percent in 1979 to 86 percent in 2012. Most of this increase has been attributed to seat belt laws, primary law upgrades, and highly visible enforcement. There has been less research on the effect of fines on seat belt usage. Methods:We examined law type and fine levels as predictors of seat belt use among fatally injured occupants of passenger vehicles from 1997 through 2008 using data from the Fatality Analysis Reporting System (FARS). Fine levels used were the statutory maximum base fines for a first offense. Results:Having a primary enforcement law was associated with a 9 to 10 percentage point increase in seat belt use. An increase in the fine amount, from the current median level of $25 to a level of $60, was associated with a 3 percentage point increase in usage. An increase in fine from $25 to $100 was associated with a 6- to 7-point increase. Such increases were in addition to the effects of a shift from secondary to primary enforcement. Discussion:The results of this study suggest that, in addition to current emphases on primary law upgrades and high-visibility enforcement of seat belt usage, increasing fine levels provides another viable strategy for increasing seat belt use. In addition, based on these results, states should consider publicizing such increases just as they publicize enforcement efforts. [ABSTRACT FROM PUBLISHER]

Objective:The lack of race information for nonfatal motor vehicle crash injuries in the United States has limited the understanding of racial disparities in motor vehicle crashes (MVCs). In this article, we describe a pilot surveillance project in Nebraska that linked crash reports and driver's license records to investigate racial disparity among nonfatal MVC injuries. Methods:The project linked 43,157 severely and nonseverely injured drivers from crash reports between 2006 and 2010 to the corresponding state driver's license database so that drivers’ race information from each MVC could be retrieved. A log rate model was used to examine the likelihood of MVC injuries by drivers’ race along the dimensions of age, sex, and place of residence. Results:Black drivers had 31.6 and 87 percent more severe and nonsevere injuries, respectively, than white drivers. Rural residents were more likely than urban residents to have severe MVC injuries. Controlling for residence status, age, and sex did not alter the basic pattern that black drivers had higher rates of nonfatal MVC injuries. Conclusions:The linkage approach provides an effective way to obtain additional information for MVC injury disparity surveillance. To reduce racial disparities in severe and nonsevere MVC injuries, race–sex-, race–age-, and race–location-specific interventions should be considered based on their significant contributions to disparity. [ABSTRACT FROM PUBLISHER]

In this study, we empirically investigate the impacts of urban road congestion and road capacity expansion on the competition between major container ports in the US. We find that more delays on urban roads may cause shippers to switch to competing rival ports: a 1% increase in road congestion delays around the port is associated with a 0.90–2.48% decrease in the port's container throughput but a 0.62–1.69% increase in the rival port's throughput. Adding local roads tends to benefit the port and harm its rival (in terms of throughput) by reducing road congestion. However, the overall impact of road provision on ports’ throughput varies among the sample ports, as road capacity expansion may affect ports’ output through channels other than road congestion delays. [ABSTRACT FROM AUTHOR]

The Desert Research Institute conducted an on-road mobile source emission study at a traffic tunnel in Van Nuys, California, in August 2010 to measure fleet-averaged, fuel-based emission factors. The study also included remote sensing device (RSD) measurements by the University of Denver of 13,000 vehicles near the tunnel. The tunnel and RSD fleet-averaged emission factors were compared in blind fashion with the corresponding modeled factors calculated by ENVIRON International Corporation using U.S. Environmental Protection Agency's (EPA's) MOVES2010a (Motor Vehicle Emissions Simulator) and MOBILE6.2 mobile source emission models, and California Air Resources Board's (CARB's) EMFAC2007 (EMission FACtors) emission model. With some exceptions, the fleet-averaged tunnel, RSD, and modeled carbon monoxide (CO) and oxide of nitrogen (NOx) emission factors were in reasonable agreement (±25%). The nonmethane hydrocarbon (NMHC) emission factors (specifically the running evaporative emissions) predicted by MOVES were insensitive to ambient temperature as compared with the tunnel measurements and the MOBILE- and EMFAC-predicted emission factors, resulting in underestimation of the measured NMHC/NOxratios at higher ambient temperatures. Although predicted NMHC/NOxratios are in good agreement with the measured ratios during cooler sampling periods, the measured NMHC/NOxratios are 3.1, 1.7, and 1.4 times higher than those predicted by the MOVES, MOBILE, and EMFAC models, respectively, during high-temperature periods. Although the MOVES NOxemission factors were generally higher than the measured factors, most differences were not significant considering the variations in the modeled factors using alternative vehicle operating cycles to represent the driving conditions in the tunnel. The three models predicted large differences in NOxand particle emissions and in the relative contributions of diesel and gasoline vehicles to total NOxand particulate carbon (TC) emissions in the tunnel. [ABSTRACT FROM AUTHOR]

Objective: The National Highway Traffic Safety Administration suggests that given the changing demographics of the United States it is important to examine motor vehicle statistics by race and ethnicity. The current study sought to explore differences in traffic safety concerns and driving behaviors between black and white drivers. Methods: An annual, anonymous, random-digit-dial telephone survey was used to collect data between 2003 and 2009 from Maryland drivers. Drivers (N = 5503) were assessed regarding their driving behaviors and perceived risk of receiving a traffic violation. Results: Results showed that black drivers perceived a greater likelihood of being stopped for driving under the influence (DUI), for not wearing a seat belt and for speeding than white drivers. These differences were found among drivers with or without a history of being ticketed. Black drivers were also more likely to report a variety of risky driving behaviors than white drivers. However, black drivers were not more likely to report receiving a ticket or citation in the last month after controlling for demographic factors, risky driving behaviors, and geographic region of the state, where traffic enforcement may vary. Conclusions: Findings indicate that black drivers are not more likely to be ticketed, despite perceptual biases that may exist among some drivers. These differences appear to be explained by demographic as well as regional factors. These results highlight the need for more research to understand the potential differences in driving behaviors between racial and ethnic groups. More research is also needed to develop countermeasures for racial and ethnic groups most at risk for motor vehicle violations and crashes. [ABSTRACT FROM PUBLISHER]

The estimation of annual average daily traffic (AADT) is an important parameter collected and maintained by all US departments of transportation. There have been many past research studies that have focused on ways to improve the estimation of AADT. This paper builds upon previous research and compares eight methods, both traditional and cluster-based methodologies, for aggregating monthly adjustment factors for heavy-duty vehicles (US Department of Transportation Federal Highway Administration (FHWA) vehicle classes 4-13). In addition to the direct comparison between the methodologies, the results from the analysis of variance show at the 95% confidence level that the four cluster-based methods produce statistically lower variance and coefficient of variation over the more traditional approaches. In addition to these findings - which are consistent with previous total volume studies - further analysis is performed to compare total heavy-duty monthly adjustment factors, both directions of traffic, with direction-based monthly adjustment factors. The final results show that the variance as well as the coefficient of variation improve on average by 25% when directional aggregate monthly adjustment factors are used instead of total direction. [ABSTRACT FROM AUTHOR]

Usually, benefits from deploying an adaptive traffic control system are measured by comparing data collected in the field before the system is installed with those collected after the system is fully operational. Such an approach is costly because it requires installation of a system before potential benefits can be observed. Nowadays to investigate effectiveness of many alternatives that were traditionally investigated in field, microsimulation is used. However, how much can one rely on results from microsimulation? There has not been a single study in which benefits of adaptive traffic control systems measured in the field are compared with those obtained through microsimulation. This study presents such a research effort. The authors compared performance measures from a field evaluation of Sydney Coordinated Adaptive Traffic System in Park City, Utah, to their counterparts from microsimulation. They collected a significant amount of data to assess system performance in the field and to help build a microsimulation model. A 14-intersection model of the Park City network was developed, calibrated, and validated on the basis of multiple data sources. The results show that a validated microsimulation model can accurately reflect field conditions although such an effort can be very challenging. [ABSTRACT FROM AUTHOR]

Advanced driving simulators have a potential to be utilized to assess crash risks of driving behaviors, traffic surroundings, and highway designs. This study focused on investigating if drivers' stop/go decisions due to signal change in the simulator's virtual reality can be used to assess rear-end crash risk at the signalized intersection. A signalized intersection with as many important features (including roadway geometries, traffic control devices, intersection surroundings, and buildings) was replicated into a high-fidelity driving simulator. Using the virtual signalized intersection, a driving simulator experiment was conducted to test driver's stop/go decisions at two approaches of the intersection that respectively showed higher and lower rear-end crash risks in the crash history analysis. The experiment results showed that the variability in drivers' stop/go decisions at the higher crash-risk location is higher than that at the lower crash-risk location. Further, through modeling rear-end conflicts based on driver's stop/go probability as a function of potential time to intersection, it was found that the rear-end crash tendency at the two locations displayed by the driver's stop/go behavior in driving simulator is consistent with the finding from the trend in crash history analysis. This research supported that driver's stop/go behavior in a driving simulator can be utilized to assess rear-end crash risk at signalized intersections to seek effective engineering countermeasures to lower crash rates for the high-risk locations. [ABSTRACT FROM AUTHOR]

The continuing growth of international container trade has created capacity problems at major US ports, and the truck-based freight transportation has caused a deterioration of traffic congestion on important US transportation corridors. Using inland and coastal waterways, short sea shipping (SSS) can provide an improvement to these problems. Furthermore, SSS offers many additional benefits for the environment, the economy and society as a whole. Both the US Department of Transportation and the European Commission actively support SSS as an alternative, environmentally friendly mode of transportation. However, there are obstacles, administrative barriers and challenges that should be addressed. Several successful operations on both sides of the Atlantic make a strong case in favour of SSS. SSS can develop customized and technologically advanced solutions that will further integrate it into the intermodal transportation chain and will improve its image among shippers as a mode that can provide reliable door-to-door transportation. This paper reviews several studies on the subject and discusses the latest developments on SSS in the US and in Europe. It also addresses the major issues and the benefits of SSS and examines the prospects for potential short sea operations in the US. Finally, it proposes research opportunities for a multimodal transportation system that will include a short sea component. [ABSTRACT FROM AUTHOR]

Traffic incidents are a major contributor to congestion on US freeways, resulting in millions of dollars in property damage and significant deaths and injuries each year. Because a single incident can cause traffic delays, equally devastating secondary incidents can result. Thus, the faster an incident is detected, verified, and cleared, the less significant the impact. Traffic cameras and other technologies are widely used for this purpose. This work examined the effectiveness of traffic cameras at five metropolitan freeway sites in South Carolina using the traffic simulation software PARAMICS to simulate various incident scenarios and traffic camera operations through application programming interfaces. The authors used these interfaces to produce random spatial and temporal occurrence of incidents, including the incident start times, durations and locations. A benefit-cost analysis based on the simulation results suggested traffic cameras returned $12 for every dollar spent under the prevailing conditions at the study sites. A sensitivity study, varying different benefit- and cost-related parameters, such as deployment costs, number of incidents, and discount rate, revealed benefit-cost values that were always above one. [ABSTRACT FROM AUTHOR]

Objectives. The objectives of the article are to assess the extent to which comparisons of motor-vehicle crash death rates can be used to determine the effectiveness of highway-safety policies over time in a country or to compare policy effectiveness across countries.Methods. Motor-vehicle crash death rates per mile traveled in the 50 U.S. states from 1980 to 2003 are used to show the influence on these rates of factors independent of highway-safety interventions. Multiple regression models relating state death rates to various measures related to urbanization and demographics are used.Results. The analyses demonstrate strong relationships between state death rates and urbanization and demographics. Almost 60% of the variability among the state death rates can be explained by the independent variables in the multiple regression models. When the death rates for passenger vehicle occupants (i.e., excluding motorcycle, pedestrian, and other deaths) are used in the regression models, almost 70% of the variability in the rates can be explained by urbanization and demographics.Conclusions. The analyses presented in the article demonstrate that motor-vehicle crash death rates are strongly influenced by factors unrelated to highway-safety countermeasures. Overall death rates should not be used as a basis for judging the effectiveness (or ineffectiveness) of specific highway-safety countermeasures or to assess overall highway-safety policies, especially across jurisdictions. There can be no substitute for the use of carefully designed scientific evaluations of highway-safety interventions that use outcome measures directly related to the intervention; e.g., motorcyclist deaths should be used to assess the effectiveness of motorcycle helmet laws. While this may seem obvious, there are numerous examples in the literature of death rates from all crashes being used to assess the effectiveness of interventions aimed at specific subsets of crashes. [ABSTRACT FROM AUTHOR]

The objective of this study is to identify the determinants of the travel demand and to assess their impacts on the number of inter- national tourist arrivals from Canada to the U.S. Annual time data (1960-2002) of tourist arrivals, real per capita income, relative prices and real exchange rates were used throughout the study. The Dummy variables of 9-11, the Olympic Games, the Open Skies Agreement, the Gulf War, the Free Trade Agreement, the World Economic Recession and the Oil Crisis were used to measure the impacts of special incidents on the number of Canadian arrivals. Multiple regression analysis was used to analyze the data. The results showed that real per capita income, relative price, the Gulf War and the Oil Crisis were the determinants of the travel demand from Canada to the U.S. [ABSTRACT FROM AUTHOR]

The paper explores relationships between seven dimensions of land use in 1990 and subsequent levels of three traffic congestion outcomes in 2000 for a sample of 50 large US urban areas. Multiple regression models are developed to address several methodological concerns, including reverse causation and time-lags. Controlling for prior levels of congestion and changes in an urban area's transport network and relevant demographics, it is found that: density/continuity is positively related to subsequent roadway ADT/lane and delay per capita; housing centrality is positively related to subsequent delay per capita; and housing–job proximity is inversely related to subsequent commute time. Only the last result corresponds to the conventional wisdom that more compact metropolitan land use patterns reduce traffic congestion. These results prove two points: that the choice of congestion measure may substantively affect the results; and that multivariate statistical analyses are necessary to control for potentially confounding influences, such as population growth and investment in the transport network. [ABSTRACT FROM AUTHOR]

This article provides a technical evaluation of the traffic control element of the Anaheim Advanced Traffic Control System Field Operations Test (FOT), sponsored by the US Department of Transportation. The primary objective for this test was the evaluation of adaptive traffic signal control technologies, including the Split Cycle and Offset Optimization Technique (SCOOT) for intersection signal control. The SCOOT evaluation was defined relative to existing, first generation Urban Traffic Control System (UTCS)-based control using standard US field detectorization. This US geometry is not the detector configuration normally used with SCOOT. SCOOT was implemented with some degree of success, though technical problems limited its performance. Anaheim's existing communication and controller systems contributed major deployment limitations since they were less adequate than anticipated. SCOOT remains in use in selected areas, with plans for system expansion. [ABSTRACT FROM AUTHOR]

Considers the exhibition "The Street" by Claes Oldenburg as a means of thinking about the possibilities for and limitations of New York City, in view of the giant, highly controversial, program of modernist urban renewal then reshaping much of the city. Significance of the book "The Steadyflow Traffic System," by Fritz Marcher to U. S. urban traffic engineering; Description of the show; Information on a symposium attended by Oldenburg.

A recent study based on data over a 10-year period (1991–2000) showed a positive association between health care utilization and prevalence of asthma, and commercial traffic at a U.S.–Canada border crossing. We wanted to determine whether decreases in total traffic would also be associated with decreases in health care utilization for respiratory illnesses. Following September 11, 2001, there was a 50% drop in total traffic at the Peace Bridge border crossing point between Buffalo, New York and Fort Erie, Ontario, Canada. To investigate the impact of such a traffic decline on health care utilization for respiratory illnesses, weekly respiratory admissions to Kaleida Health System, Western New York's largest health care provider were analyzed according to ICD9CM classification and compared with total weekly traffic volumes for 3-month periods in 2000 and 2001 (August, September, and October). The total number of patients admitted to hospital or seen in emergency departments for respiratory illnesses during the 3-month periods of both years was 5288. A 50% drop in total traffic following Labor Day and September 11, 2001, from week 4 to week 7 was found to be statistically significant (p = 0.031) when a one-way ANOVA was performed. Likewise, the drop in total respiratory cases approached statistical significance (p = 0.052) when a one-way ANOVA was conducted. The results suggest an association between decrease in traffic volumes with decrease in health care utilization for respiratory diseases. These results suggest that current levels of traffic may be impacting on the respiratory health of residents in the nearby community. [ABSTRACT FROM AUTHOR]

Presents a method for studying the impact of road traffic flows on marine container terminals located in highly congested areas. Urban planning for Hampton Roads, Virginia; Opening a section of interstate highway; Projected doubling of container traffic at one terminal; Daily unit train in the vicinity of another terminal.

Objective:The anthropomorphic test devices (ATDs, or crash dummies) used in the assessment of vehicle crash protection were created based on particular anthropometric targets. The Hybrid-III ATDs widely used in the U.S. are commonly called the “5th-percentile female”, “50th-percentile male”, and “95th-percentile male” ATDs, referring to selection of the respective percentiles of the male and female U.S. adult populations as design targets for the ATDs. The objective of this work was to assess whether secular trends in U.S. anthropometry have affected the relationship between the ATDs and the population. Method:The corresponding percentiles were calculated from data obtained in the National Health and Nutrition Examination Survey (NHANES) for the years 2005–2008. Results:The results showed that the ATD stature targets differ from the current population by less than 5 percentile points, but the discrepancies for mass are much larger for the two male ATDs. Conclusions:The reference mass for the midsize-male Hybrid-III ATD of 78.2 kg is now the 33rdpercentile body mass for U.S. adults, and the large-male ATD reference body mass of 102.5 kg is now the 81stpercentile. The implications of these differences are discussed in the context of restraint system design. [ABSTRACT FROM PUBLISHER]

This article reports on the increase in collisions between cars and deer in the U.S. as of October 1990, due to the growth of deer population and the migration of human population into formerly rural areas. The National Safety Council estimates that up to 350,000 deer and more than 100 motorists die each year from such collisions. Officials have responded by posting signs and installing reflectors along roads, expanding deer-hunting seasons, setting up off-road feeding stations to discourage the deer from crossing roads in search of food, and even building underpasses for deer. Some motorists are taking precautions of their own, and a small industry has sprung up marketing bumper-mounted ultrasonic whistles that frighten deer off the road. However, the efficacy of the whistles is debated. The problem continues to grow, especially in areas like Princeton Township in New Jersey, where hunting is banned altogether.