Author: Michelle Mekker
Publisher:
ISBN: 9781622604579
Category :
Languages : en
Pages :
Get Book Here
Book Description
In Indiana, distracted driving and unexpected queues have led to an increase in the amount of back-of-queue crashes, particularly on approach to work zones. This report presents new strategies for the assessment of both transportation safety and traffic operations using crowd-sourced probe vehicle data and a speed laser vehicle re-identification scheme. This report concludes by recommending strategies for the placement of variable speed limits (VSL) adjacent to work zones and suggestions for future research.
Author: Matt Riffkin
Publisher:
ISBN:
Category : Highway communications
Languages : en
Pages : 37
Get Book Here
Book Description
Technological advances allow speed limits to be changed in real time based on actual roadway conditions. There may be potential advantages to using variable speed limits in Utah, such as for traffic control during construction where the speed limit may be lowered adjacent to actual construction activities versus at other times or locations within an established work zone. This research will test the compliance and derive potential advantages from the use of variable speed limit equipment.
Author:
Publisher: Transportation Research Board
ISBN: 9780309065023
Category : Business & Economics
Languages : en
Pages : 444
Get Book Here
Book Description
TRB Special Report 254 - Managing Speed: Review of Current Practices for Setting and Enforcing Speed Limits reviews practices for setting and enforcing speed limits on all types of roads and provides guidance to state and local governments on appropriate methods of setting speed limits and related enforcement strategies. Following an executive summary, the report is presented in six chapters and five appendices.
Author: M. Papageorgiou
Publisher: Pergamon
ISBN:
Category : Business & Economics
Languages : en
Pages : 686
Get Book Here
Book Description
"The vast expansion of transportation systems on land, sea and in the air throughout the twentieth century has allowed for the development of economic, social and political connections across the globe undreamed of by our ancestors. However, this expansion has brought with it familiar problems such as airport delays and gridlock in our major cities. Fortunately, parallel progress in system science and information technology can provide us with the appropriate tools for rational and efficient solutions to our exponentially increasing transportation demands. This encyclopedia addresses the analysis, modelling and control of today's and tomorrow's traffic and transportation systems in a concise, comprehensive single volume. Well over 100 articles have been specially commissioned, or revised from the acclaimed Systems & Control Encyclopedia, to provide an overview of and first reference to models, control methods and practical aspects of all forms of traffic and transportation systems with a particular emphasis on efficient utilization of available infrastructure, plus a consideration of their historical, organizational, economic and social impacts. The Concise Encyclopedia of Traffic & Transportation Systems will be essential for professional and academic scientists and engineers in any discipline concerned with the movement of people and materials."--Book description, Amazon.com.
Author: Emily C. Layton
Publisher:
ISBN: 9781124925202
Category : Variable speed limits
Languages : en
Pages : 114
Get Book Here
Book Description
Speed limits are generally created for ideal road conditions. When road conditions deteriorate, speed limits tend to become unreasonable, and enforcement of safe driving becomes difficult. Variable speed limit (VSL) systems are used to adjust speeds in accordance with the changing conditions in an attempt to reduce the variation of speeds among all vehicles. This research highlights the findings from the variable speed limit system in place along the Elk Mountain Corridor of I-80 in Southeastern Wyoming during the first and second full winter seasons of VSL implementation. Specifically this research focuses on speeds and variations of speed and the effect the VSL system has had on individual vehicles. The objective of this research was to determine if the VSL system was effective in reducing speeds and speed variation during adverse conditions. Further, this analysis attempts to determine the effect of the VSL system on driver behavior. The VSL system was effective at reducing speeds when properly implemented, reduced speed variation as well. Drivers respond differently to different levels of VSL implementation.
Author: Europump & the Hydraulic Europump & the Hydraulic Insti
Publisher: Elsevier
ISBN: 0080520464
Category : Technology & Engineering
Languages : en
Pages : 185
Get Book Here
Book Description
Prepared by industry experts from the pump, motor and drive industries under the auspices of Europump and the Hydraulic Institute, this reference book provides a comprehensive guide to variable speed pumping.It includes technical descriptions of pumping systems and their components, and guides the reader through the evaluation of different speed control options.Case studies help illustrate the life cycle cost savings and process improvements that appropriate variable speed pumping can deliver.·Authoritative, global reference to Variable Speed Pumping, by Europump and the Hydraulic Institute·Combines the technical knowledge of pump, motor and control systems in one guide·Brings together all the concepts, metrics and step-by-step decision-making support you need to help you decide which VSD strategies are most appropriate·Will help you design and specify pumping applications that minimise life-cycle costs
Author: Curt P. Harrington
Publisher:
ISBN:
Category :
Languages : en
Pages : 77
Get Book Here
Book Description
Static speed limits are the norm across the world's roadway networks. However, advances in technology and increased applications in intelligent transportation systems (ITS) provide a mechanism for upgrading traditional speed limits into an active traffic management system. More specifically, variable speed limits (VSLs) can be used in high crash severity locations and in real-time congestion and weather events to increase traffic safety and operations. Much of the available literature on VSLs focuses upon crash prediction algorithms for VSLs, simulations, and effectiveness of real-world VSL implementations. One noticeable gap in the existing literature is related to driver compliance under varied configurations of alerting drivers of the variable speeds. An additional gap in literature is related to existence of a conceptual framework for identifying optimal corridors for potential VSL implementation. Within this thesis drivers' willingness to comply with VSLs was investigated via focus groups and static surveys during the experimental process. Connections are made between driver speed choice and type of speed limit condition including uniform speed vi limit (USL) versus VSL, overhead mount versus side mount, presence of an explanatory message, and the numerical speed limit value. An analysis of the survey results was completed to isolate critical factors in VSL compliance. Opinions and perspectives on VSLs are derived through the focus group sessions Lastly, a case study approach is presented in which a region is chosen, and implementation metrics are analyzed on the major roadway networks using a GIS platform to create a composite ranking system for potential optimal VSL corridors. The study aims to be used as a foundation to justify use of certain types of VSLs in addition to creating a conceptual framework for VSL implementation zone identification.
Author: Fiona Fylan
Publisher: Wallflower Press
ISBN: 9781904763673
Category : Speed limits
Languages : en
Pages : 105
Get Book Here
Book Description
Summarises the results of research undertaken by two independent research groups (Brainbox Research and the University of Leeds) into the components of interventions that are most likely to change the behaviour of speeding drivers. This work also reports the discussions and consensus of an expert group meeting of scientists and stakeholders.
Author: Daniela E. Gonzales
Publisher:
ISBN:
Category : Roads
Languages : en
Pages : 0
Get Book Here
Book Description
Low visibility conditions can inhibit a driver's ability to perceive appropriate operating speeds, particularly during foggy conditions in which the characteristics of the fog can vary spatiotemporally. By reducing visibility and contrast in the visual field, fog obscures crucial driving cues essential for perceiving depth and speed. Studies have shown that fog-related crashes are more likely to involve multiple vehicles and severe injuries than crashes during clear conditions. Numerous agencies have installed countermeasures such as weather advisory systems and variable speed limits (VSLs) to mitigate these conditions, but not many studies have quantitatively analyzed the results of these countermeasures. In October 2016, the Virginia Department of Transportation (VDOT) activated a VSL system on a 12-mile section of I-77 that runs through mountainous terrain in southwestern Virginia. The area is known to have severe, recurring fog events, so the VSL system was installed to reduce the quantity and severity of crashes in the corridor. This study assessed how the I-77 VSL system has affected speeds and crash characteristics since its activation. Before the installation of the VSL, drivers frequently drove much faster than the safe speed based on the stopping sight distance during fog. The purpose of the VSL system was to influence drivers to travel closer to the safe speed during reduced visibility events by posting appropriate reduced speed limits. The analysis examined the effect of the VSL system on driver speeds before and after activation at a single site and after activation across the corridor. Effects on crashes for the entire corridor were also examined. The results showed statistically significant reductions in mean speeds and variances after the VSL was activated, and drivers drove closer to the safe speed based on available visibility. Models developed to understand how the VSL system affected speed as a function of visibility showed that speeds were reduced by a statistically significant amount when VSLs were active. Trends in speed by posted speed limit were examined across the corridor, and it was found that compliance generally improved once drivers encountered reduced visibilities. Speeds did not change as much in transition areas leading into the area where the fog was present, however. Crash analysis revealed only two fog-related crashes in the after period, yielding reduced crash rates during low visibility conditions and indicating improved safety. These safety results are considered preliminary, however, because of limited after data. The results of this VSL implementation may be used to refine the current VSL control algorithm to improve compliance even further and could also serve as a reference for other agencies contemplating alternatives to improve safety at fog-prone areas. Given the results, it is recommended that VDOT's Southwest Region Operations convene a group to modify the VSL control algorithm. It is further recommended that the Virginia Transportation Research Council re-evaluate the safety effects of the system after at least 3 years of after data are available to make a more definitive determination of the safety effects of the system and to determine its return on investment. Implementation of these recommendations could further improve the efficacy of the system and result in a better quantification of the full benefits of the system.
Author:
Publisher: Transportation Research Board
ISBN: 0309129265
Category : Technology & Engineering
Languages : en
Pages : 268
Get Book Here
Book Description
"Reliability of transport, especially the ability to reach a destination within a certain amount of time, is a regular concern of travelers and shippers. The definition of reliability used in this research is how travel time varies over time. The variability can apply to the travel times observed over a road segment during a specific time slice (e.g., 3 to 6 p.m.) over a fairly long period of time, say a year. The variability can also pertain to the travel times of repeated trips made by a person or a truck between a given origin and destination. Agencies are increasingly aware of the issue of reliability, although the transportation industry as a whole as yet lacks a firm understanding of the causes and solutions to failures of reliability. As the agenda for the SHRP 2 research on travel time reliability took shape, it became clear a fundamental study was required to be able to talk about travel time reliability in a meaningful way"--Foreword.
