Nemzetközi szemle: Február
Megosztott mobilitás. Új megoldás élhető városok számára
Shared Mobility. Innovation for Liveable Cities
International Transport Forum
Terjedelem: 56 oldal
The way in which people move has undergone several revolutions in the past: from walking on foot, to animal-powered mobility, to vehicles propelled by combustion engines using fossil fuels. Today the next mobility revolution is underway, based on the use of real-time streams of data that make it easier and more efficient to provide citizens with optimised access to their cities. This report investigates one particular scenario that evidence suggests could occur: the large-scale deployment of shared vehicle fleets that provide on-demand transport. Building on our 2015 report Urban Mobility System Upgrade: How Shared Self-driving Cars Could Change City Traffic, this study models the impact of replacing all car and bus trips in a city with mobility provided through fleets of shared vehicles. The simulation is, again, based on real mobility and network data from a mid-size European city, namely Lisbon, Portugal. In this follow-up study, we examine a different configuration where shared mobility is delivered by a fleet of six-seat vehicles (“Shared Taxis”) that offer on-demand, door-to-door shared rides in conjunction with a fleet of eight-person and 16-person mini-buses (“Taxi-Buses”) that serve pop-up stops on demand and provide transfer-free rides. Rail and subway services keep operating in the current pattern. The simulation looks at impacts on the number of vehicles required and the total kilometres driven, and the effects on congestions, CO2 emissions and use of public space. Additionally – and crucially – it also examines how citizens experience the new shared services and how they affect social inclusion measured in the level of accessibility of jobs, schools and health services.
Dinamikus tengelyterhelési rendszerek irodalmi áttekintése a hosszú távú hídviselkedési program számára
LTBP Program’s Literature Review on Weigh-in-Motion Systems
I. Al-Qadi, H. Wang, Y. Ouyang, K. Grimmelsman, J. Purdy
Pennoni Associates Inc. USA
Terjedelem: 46 oldal
Truck size and weight are regulated using Federal and State legislation and policies to ensure safety and preserve bridge and high infrastructure. Weigh-in-motion (WIM) systems can capture the weight and other defining characteristics of the vehicles actually using the Nation’s highways, providing important loading-related data that is essential for evaluating the performance of transportation infrastructure. As part of the Federal Highway Administration’s (FHWA) Long-Term Bridge Performance (LTBP) Program’s Technical Assistance Contract, a literature review of the state of the practice was performed for WIM systems installed in pavements and on bridges. This literature review focused on the development of WIM systems, concepts for measuring axle loads, the applications of WIM sensors for pavements, and recent advancements in bridge WIM system. This review covers the types, installation, calibration, operations, accuracy, efficiency, effectiveness, and durability of WIM systems, in addition to current Federal and State truck load regulations. This review facilitates selection of the appropriate WIM technology systems for consideration and use to address LTBP Program needs. This literature review serves as a reference document for Pooled Fund Project Number TPF-5(283), The Influence of Vehicular Live Loads on Bridge Performance, which targets the impact of vehicle live loads on bridge component durability.
A vezetői viselkedés kezelése az összekapcsolt és automatizált járművek szimulációjában
Incorporating Driver Behaviors into Connected and Automated Vehicle Simulation
P. Songchitruksa, A. Bibeka, L.I. Lin, Y. Zhang
Texas A&M Transportation Institute, Advancing Transportation Leadership and Safety (ATLAS) Center, USA
Terjedelem: 104 oldal
The adoption of connected vehicle (CV) technology is anticipated at various levels of development and deployment over the next decade. One primary challenge with these new technologies is the lack of platform to enable a robust and reliable evaluation of their benefits given the complexity of interactions among wireless communications, algorithms, and human behaviors. Underlying driver behavior models in microscopic simulation are not always well-suited for modern applications using CV and automated vehicle (AV) technology.
This study proposed a framework for incorporating realistic driver behaviors into a microscopic traffic simulation for AV/CV applications using VISSIM microscopic simulation software. The framework consists of three levels of driver behavior adjustment: event-based, continuous, and semi-automated/automated driver behavior adjustment. The framework provides several examples and details on how various applications can be properly modeled in a traffic simulation environment.
To demonstrate the framework, researchers conducted a case study of a simulation evaluation of cooperative adaptive cruise control (CACC). CACC enables the vehicles to follow each other in a very tight spacing (also known as platooning) using wireless connectivity and automated longitudinal control. The case study shows that a modified driver model can be successfully used in the simulation to evaluate the benefits of AV/CV applications such as CACC with respect to their mobility, safety, and environmental performance.
70 mérföld/óra tanulmány
E.T. Donnell, B. Hamadeh, L. Li, J.S. Wood
The Pennsylvania State University USA
Terjedelem: 145 oldal
In July and August 2014, the Pennsylvania Department of Transportation (PennDOT) and Pennsylvania Turnpike Commission (PTC) raised the posted speed limit on rural sections of Interstates 80, 380, and 76 from 65 to 70 mph. The purpose of this study was to assess the speed and safety performance of these “pilot” sections. This was done by comparing the operating speeds and crash frequencies before and after the posted speed limit increase. Additionally, operating speed data in several work zones were collected to assess how drivers comply with posted speed limits in work zones on the pilot sections. An inferred design speed method and pavement friction degradation method are proposed as methodologies to assess site conditions on rural Interstate roadways with 65 mph posted speed limits. Collectively, the operating speed, safety, inferred design speed, and friction information can be used by PennDOT and the PTC to identify candidate locations for 70 mph posted speed limits. The findings suggest that mean and 85th-percentile operating speeds increased after increasing the posted speed limit from 65 to 70 mph; however, the increases were less than 5 mph. A framework was developed to estimate the safety effects of the posted speed limit increase, because only 12 to 16 months of after period crash data were available for the analyses included in this study.
Részleges mélységű beton burkolat javítások teljesítménye
Performance of Partial-Depth Concrete Pavement Repairs
Tom Burnham, Eddie Johnson, Ben Worel
Minnesota Department of Transportation USA
Terjedelem: 38 oldal
The original concrete pavement test sections at the MnROAD facility, constructed in 1993, utilized older generation Minnesota concrete pavement mix designs. By 2011, several of the original concrete pavement test sections that remained in service began to exhibit materials related distress along the joints which required partial-depth repairs to keep them in service. This created an opportunity to evaluate both existing and new types of patching materials. This report describes the 3 year performance of 93 patches with 22 different materials. Subjective condition ratings, based primarily on visual observations, were made over the 3 year evaluation period. A sounding, using a ball-peen hammer, provided bond condition information for each patch in October 2014. Results were tabulated by MnROAD test cell number and patch material designation. Since patch performance can be affected by direct tire loading, tables organized by patch location and material type were also presented. Finally, a photographic record of each patch with condition ratings over time was included in the appendix. Overall, 55 of the 93 (59%) patches remained in good serviceable condition as of October 2014. The location of the patch did not seem to affect the performance significantly, with 61% and 67% of the patches in good condition near the center line and loaded areas, respectively. While they are not often used for modern projects, many of the slower setting and strength gaining products demonstrated a higher survivability rating.
A gépkocsi használat változásainak megértése: különböző térbeli léptékű statisztikai mérőszámok elemzése a Nagy-Britanniában regisztrált személygépkocsik adataiból
Understanding variation in car use: exploration of statistical metrics at differing spatial scales using data from every private car registered in Great Britain
S.D. Ball, S. Cairns, P. Emmerson, R. E. Wilson, J. Anable, T. Chatterton
Transport Research Laboratory (TRL), University of Bristol, University of Leeds, University of the West of England, UK
Terjedelem: 10 oldal
Assessment of vehicle use is often based on looking at average mileages, and how those vary. However, it is argued that transport policies, or other factors, may impact relatively subtly on different groups within populations, in ways which might be difficult to detect by looking at differences in, or changes to, averages. This paper reports on unique opportunities arising from a research project that is fusing and analysing several UK Government data sources together for new purposes – specifically, data collected for vehicle licensing and from regular vehicle inspections. In particular, the resultant dataset provides a unique opportunity to look at the distribution of mileages travelled by vehicles registered in different areas, and to understand how and why those distributions may differ, and which characteristics of those distributions may be most insightful for identifying and understanding the variation. This paper describes the analysis undertaken at a range of spatial scales and the calculation of a range of statistics to describe the vehicle distributions, and assessing the extent to which they differ, and what that might imply.
Együttműködő intelligens közlekedési rendszerek. Kutatási téma elemző jelentés
Cooperative Intelligent Transport Systems. Research Theme Analysis Report
Transport Research & Innovation Portal, EU
Terjedelem: 100 oldal
The purpose of TRIP is to collect, structure, analyse and disseminate the results of EU-supported transport research, research financed nationally in the European Research Area (ERA) and selected global research programmes. The TRIP web portal can be found at www.transport-research.info
This research theme analysis report gives an overview of research performed (mostly) in the EU collated by TRIP, providing a view across many projects that fall under the theme title. It provides an assessment of the reported results from these projects and offers perspectives from scientific and policy points of view. This assessment aims to consider: overall trends in C-ITS research, including key results; overall trends in the research funding; the alignment of the research with current policy; policy implications of the results from the research; any gaps in the research theme. For the purpose of this review, the theme of C-ITS has been divided into 10 sub-themes and the assessments performed within each sub-theme as well as across the complete C-ITS theme. The 10 sub-themes considered are: communication technologies; data protection and security; freight transport and logistics; human-machine interaction; information systems/platform; motorway applications; public transport; safety, efficiency and emissions; sensors; urban applications.
Mobilitás, mint szolgáltatás – a lehetőségek felfedezése az Egyesült Királyságban
Exploring the Opportunity for Mobility as a Service in the UK
Transport Systems Catapult, UK
Terjedelem: 52 oldal
Our research shows that travellers and other transport users increasingly view transport as a service which they want to buy when they need it. Our transport services need to better suit customers’ circumstances and provide options that align with their lifestyles. One size fits all is no longer an option. Dynamically updated and user-relevant information should be the norm, not an exception. This is evident in the way customers adopt services such as Uber. In the future, this trend will continue due to growth of urban populations and changing preferences of younger generations that care less about ownership and more about experiences. This trend will be especially evident when the car industry confronts an environment where customers prefer not to buy cars but instead require only occasional access to a vehicle and service – this represents a clear shift from an ownership model, to a service model. The availability of data, processing power and the ubiquitous use of mobile phones have enabled travellers and their needs to be better understood. Passengers no longer need to collect and keep timetables to work out the most optimal connections between transport modes. There is a plethora of personalised apps designed to serve travellers – these apps deliver information in real-time to help avoid congestion and delays and enable the customer to choose a travel option according to the specific travel need. Tailored travel options can be made possible – whether it is the fastest route, low-cost route, most direct route, most environmentally friendly, or most accessible service for persons with reduced mobility, or those travelling with children. This is all enabled by technological advancement, combined with the rise of new business models such as Mobility as a Service (MaaS).
Költség-haszon elemzés a közlekedéstervezésben és a közösségi politikában – a multimodális igénymodellek felé.
Benefit-Cost Analysis for Transportation Planning and Public Policy: Towards
Multimodal Demand Modeling
M. Holian, R. McLaughlin
Mineta Transportation Institute, USA
Terjedelem: 76 oldal
This report examines existing methods of benefit-cost analysis (BCA) in two areas, transportation policy and transportation planning, and suggests ways of modifying these methods to account for travel within a multimodal system. Although the planning and policy contexts differ substantially, this report shows how important multimodal impacts can be incorporated into both by using basic econometric techniques and even simpler rule-of-thumb methods. Case studies in transportation planning focus on the California Department of Transportation (Caltrans), but benchmark California’s competencies by exploring methods used by other states and local governments. The report concludes with a list and discussion of recommendations for improving transportation planning models and methods. These will have immediate use to decision makers at Caltrans and other state DOTs as they consider directions for developing new planning capabilities. This project also identifies areas, and lays groundwork, for future research. Finally, by fitting the planning models into the broader context of transportation policy, this report will serve as a resource for students and others who wish to better understand BCA and its use in practice.