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Because of the serious societal, environmental, economic, and public health problems associated with motorized transportation, there is increased interest in encouraging non-motorized modes of travel. The current study contributes...
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Because of the serious societal, environmental, economic, and public health problems associated with motorized transportation, there is increased interest in encouraging non-motorized modes of travel. The current study contributes toward this objective in two ways. First, it evaluates the operational impacts of bicycling adjacent to on-street parking. Second, it identifies the importance of attributes influencing bicyclists route choice preferences. The importance of evaluating both operations and individual preferences at the same time is the interrelationship between the two; poorly designed roadways may encourage cyclists to leave designated bicycle routes. Operationally, this study examines field data that was collected in Austin, Houston, and San Antonio and resulted in over 6,400 observations of motorists and/or cyclists adjacent to on-street parking. From the data, multivariate regression models were developed to predict the motorists and cyclists position on the roadway and the probability of motor vehicle encroachment. The models indicate that on-street parking has a significant impact on motorist and cyclist position; a bike lane combined with a buffer space is the only way to completely remove cyclists from the door zone, and operationally, a bicycle lane is more effective than a wide outside lane. As a result of the study, the Texas Guide for Planned and Retrofit Bike Facilities was updated to include on-street parking. In evaluating route choice, the study specifically examines a comprehensive set of attributes that influence bicycle route choice, including: (1) bicyclists characteristics, (2) on-street parking, (3) bicycle facility type and amenities, (4) roadway physical characteristics, (5) roadway functional characteristics, and (6) roadway operational characteristics. The data used in the analysis is drawn from a web-based stated preference survey of Texas bicyclists. The results of the study emphasize the importance of a comprehensive evaluation of both route-related attributes and bicyclists demographics in bicycle route choice decisions. The empirical models indicate that travel time is the most important attribute for commuters in choosing their routes. These factors also impact bicyclists route choice: traffic volume; speed limit; on-street parking characteristics; bicycle route continuity; number of stop signs, red lights, and cross streets; and roadway terrain.
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The overall goal of the Federal Highway Administrations (FHWA) Visibility Research Program is to enhance the safety of road users through near-term improvements of the visibility on and along the roadway. The program also promotes...
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The overall goal of the Federal Highway Administrations (FHWA) Visibility Research Program is to enhance the safety of road users through near-term improvements of the visibility on and along the roadway. The program also promotes the advancement of new practices and technologies to improve visibility on a cost-effective basis. The following document summarizes the results of a study on the visual performance of drivers during nighttime driving in clear weather. The study was conducted under Phase II of the Enhanced Night Visibility (ENV) project, a comprehensive evaluation of evolving and proposed headlamp technologies under various weather conditions. The individual studies within the overall project are documented in an 18-volume series of FHWA reports, of which this is Volume III. It is anticipated that the reader will select those volumes that provide information of specific interest. This report will be of interest to headlamp designers, automobile manufacturers and consumers, third-party headlamp manufacturers, human factors engineers, and people involved in headlamp and roadway specifications.
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It is assumed that installation of bicycle facilities will result in an increase in the number of bicyclists. However, it is rare that any kinds of before and after counts are performed and reported in the literature. The report f...
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It is assumed that installation of bicycle facilities will result in an increase in the number of bicyclists. However, it is rare that any kinds of before and after counts are performed and reported in the literature. The report focuses on the before-after change in the amount of bicycle riding associated with the installation of bicycle lanes along two corridors, 31st and 37th streets in St. Petersburg, Florida, with low levels of bicycling. For all data collection location, model results showed a 17.1% increase in the bicycles per day after installation of the bike lanes (from 9.06 to 10.49 bicycles per day using the raw count data). When 31st and 37th streets were examined separately, 31st Street experienced almost no change in counts (10.43 to 10.22 bicycles per day using the raw count data). This 3% reduction was not statistically significant. After bicycle lanes were introduced, 37th Street experienced a statistically significant 42% increase in counts, although the change in the raw counts from before to after was only 7.59 to 10.74 bicycles per day. Bicycle average speeds were approximately 11-12 mph before and after the bike lane installation. The study shows that the addition of bicycle lanes alone on a street will not guarantee an immediate increase in bicycle volume. Other factors, including adjacent land use, convenient origins and destinations, and connectivity of a bicycle lane to other bicycle facilities within the street system are just as, or perhaps more critical, in terms of encouraging bicycling.
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The report focuses on colored (green) pavement and accompanying signing used in St. Petersburg, Florida in a bike lane weaving area, where motor vehicles cross the bike lane, near an intersection. The objective was to determine if...
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The report focuses on colored (green) pavement and accompanying signing used in St. Petersburg, Florida in a bike lane weaving area, where motor vehicles cross the bike lane, near an intersection. The objective was to determine if the painting and signing highlighting these areas changed the behavior of bicyclists and motorists at the selected location using videotapes made before and after the green pavement and signing treatments were installed. A significantly higher percentage of motorists yielded to bicycles in the after period. The percentage of motorists that signaled their intention to turn right increased significantly from the before to the after period. A significantly higher percentage of bicycle riders scanned for proximate vehicles in the after period. While the percentage of conflicts (sudden changes in speed or direction) was lower in the after period, the differences were not statistically significant. Most of the conflicts were between motorists maneuvering near the bicyclists. It was not surprising to see a large number of motorists in a queue maneuvering to get into the right-turn lane. In times of busy motor vehicle traffic, this location was a severe test of the green bike lane weaving area. The significant increase in yielding behavior by motor vehicles is an important finding and matches what was found in the earlier evaluation of the blue bike lane weaving areas in Portland, Oregon.
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Demographic changes show that the absolute number and portion of the population in Europe that can be categorized as older or very old will continue to grow over the next several years. One aim should be to keep them active and he...
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Demographic changes show that the absolute number and portion of the population in Europe that can be categorized as older or very old will continue to grow over the next several years. One aim should be to keep them active and healthy for as long a time as possible. Exercise, for example cycling, plays an important role in this context but data shows that the elderly bicyclists are overrepresented in crashes when compared with their exposure to traffic. Senior cyclists. needs and preferences should be a base for developing a safe and joyful cycling environment. A special focus is how to use Intelligent Transport Systems, ITS, to increase safety and quality. This project uses literature reviews, in-depth crash data analysis, questionnaires with senior cyclists, questionnaires with experts, and an expert workshop to identify potential ITS applications for improving elderly bicycling. The last tool (the expert workshop) included two group discussions structured according to two philosophically different models: The Diamond model and The Multiple comfort model. All tools tested here seem to work well together for developing ideas for countermeasures that ensure safe and joyful cycling for senior citizens. With one exception, all aspects mentioned in the expert questionnaire were taken up in group discussions in the expert workshop. Probably, Intelligent Speed Adaptation on cars is the most efficient measure to provide safe cycling, but other ITS measures are also needed to provide safe and joyful cycling for senior citizens and raise the profile of cycling as such. ITS measures could be linked to, or built into, existing equipment such as navigation systems, cycle computers, and traffic signal control boxes. ITS measures could also increase the comfort for elderly cyclists, e.g. automatic locking and opening of bicycles at a distance by using the key as for cars with remote controlled locks.
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This report summarizes the findings of a national project to examine the travel behavior, social capital, health, and lifestyle preferences of residents of neotraditional developments (NTD) compared to more standard suburban devel...
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This report summarizes the findings of a national project to examine the travel behavior, social capital, health, and lifestyle preferences of residents of neotraditional developments (NTD) compared to more standard suburban developments. We compare survey results from residents of matched pairs of neighborhoods in seventeen U.S. cities and towns, with each pair comprised of one NTD and one typical suburban neighborhood of similar size, age, and socio-demographic composition. The study addresses salient themes in the transportation, planning and health literatures: a national study, surveying populations of diverse incomes, collecting resident information on preferences for and attitudes towards neighborhood qualities, and addressing transportation and health outcomes for diverse community designs.
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Road Safety Audits (RSAs) are a formal safety examination of an existing or future roadway or off?road facility and are conducted by an independent, experienced, multidisciplinary team. The purpose of the Bicycle Road Safety Audit...
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Road Safety Audits (RSAs) are a formal safety examination of an existing or future roadway or off?road facility and are conducted by an independent, experienced, multidisciplinary team. The purpose of the Bicycle Road Safety Audit Guidelines and Prompt Lists is to provide transportation agencies and RSA teams with a better understanding of the safety of cyclists in the transportation system when conducting an RSA. These Guidelines present the RSA team with an overview of basic principles of the safety of cyclists and potential issues affecting cyclists. They also provide information on how to conduct an RSA and effectively assess the safety of cyclists. Prompt lists describe safety considerations when conducting a cyclist?specific RSA. These Guidelines will help RSA teams evaluate and suggest a multimodal approach to safety by improving the safety of cyclists and all roadway users
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Transportation Research Record (TRR): Journal of the Transportation Research Board, No. 2520 consists of 16 articles that summarize computer vision techniques to collect helmet-wearing data on cyclists; an evaluation of interactio...
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Transportation Research Record (TRR): Journal of the Transportation Research Board, No. 2520 consists of 16 articles that summarize computer vision techniques to collect helmet-wearing data on cyclists; an evaluation of interactions between buses and bicycles at stops; a visual survey tool for determining factors that make a street attractive for bicycling; red light running behavior of electric bicycles at signalized intersections in China; the dispersion effect in left-turning bicycle traffic and its influence on capacity of left-turning vehicles at signalized intersections; and mode choice and spending behavior in downtown Davis, California. This TRR also explores a cost–benefit analysis of added cycling facilities; day-of-year scaling factors and design considerations for nonmotorized traffic monitoring programs; applying diffusion of innovation theory to use of a public bikeshare system in Vancouver, Canada; modeling the impacts of bicycle facilities on work and recreational bike trips in Los Angeles County, California; and measuring traffic reduction from bicycle commuting. Additionally, this TRR examines a comparative analysis of annual average daily bicyclist traffic estimation methods; attitudes toward mode choice and multimodal commuting to work by public transport and bicycle; electric bikes in North America; a disaggregate-level assessment of changes to Michigan’s motorcycle helmet use law and its effects on motorcyclist injury outcomes; and characterizing usage patterns for powered two-wheelers from automatic vehicle identification data in Melbourne, Australia.
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Researchers have shown that GPS units in smartphones can be used to identify routes taken by cyclists, including whether cyclists deviate from shortest paths to use bike lanes and other facilities. Researchers previously have not ...
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Researchers have shown that GPS units in smartphones can be used to identify routes taken by cyclists, including whether cyclists deviate from shortest paths to use bike lanes and other facilities. Researchers previously have not reported whether GPS tracking can be used to monitor whether and how bicyclists actually use lanes on streets, where these lanes have been provided, or other types of facilities. The objective of this research was to determine whether smartphone GPS units or enhanced GPS units could be used to track and map the location of cyclists on streets. The research team modified an open-source smartphone application (CycleTracks) to integrate with a higher-quality external GPS unit. Cyclists then mounted the smartphone with route-tracking applications to bicycles and repeatedly rode four different routes. The routes for the field tests were chosen because each included a striped lane for bicycle traffic and because the routes bisected a variety of built urban environments, ranging from an open location on a bridge over the Mississippi River to a narrow urban street lined by tall, multi-story office buildings. The field tests demonstrated that neither the smartphone GPS units nor the higher-quality external GPS receiver generate data accurate enough to monitor bicyclists use of bike lanes or other facilities. This lack of accuracy means that researchers interested in obtaining data about the propensity of cyclists to ride in lanes, when available, must rely on other technologies to obtain data for analyses.
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