A közlekedésépítési szakterület mérnöki és tudományos folyóirata. ISSN: 2064-0919
15. szám
9. évfolyam
2021 július
15
Bejegyzés

Nemzetközi szemle: Április

A közösségi és az egyéni mobilitás között – új technológiák a közlekedési szolgáltatásban
Between Public and Private Mobility Examining the Rise of Technology-Enabled Transportation Services
Szerző(k): Committee for Review of Innovative Urban Mobility Services UKTransportation Research Board, USA

Terjedelem: 126 oldal

Information and communication technologies, combined with smartphone applications and location data from global positioning systems, are making feasible transportation services that have long been imagined but never realized on a large scale. These innovations include carsharing; bikesharing; microtransit services; and, most notably, transportation network companies (TNCs) such as Uber and Lyft. These services are being embraced by millions of travelers who are using their smartphones to arrange for trips by car, shuttle, and public transit, as well as for short-term rental of cars and bicycles. The rapid growth in these services follows and amplifies a rebound in travel by taxis and public transit that began more than a decade ago. The new services epitomize today’s sharing economy and allow an increasing number of people to enjoy the mobility benefits of an automobile without owning one, and may encourage others to leave their personal vehicle at home for the day, reduce the number of vehicles in their household, or even forgo having one at all. Notably, most of these innovations are occurring and being deployed in the private sector without public financial support, with the exception of bikesharing, which is typically publicly subsidized. Whereas TNCs have received the lion’s share of media attention to date, the other innovative mobility services are growing, evolving, and expanding mobility while also reducing personal vehicle travel, greenhouse gas emissions, and possibly automobile ownership. Although travel using innovative mobility services still represents a small share of total trips, a continued increase in customers and trips has substantial implications for the future. To date, the most rapidly growing forms of shared mobility entail sequential sharing of vehicles, with each user in turn having exclusive use of a motor vehicle or bicycle. Potentially more consequential, but still in its infancy, is concurrent sharing of vehicles among strangers. By increasing vehicle occupancy, this form of shared services may collectively have greater effects—in terms of affordable personal mobility, vehicle use, energy consumption, traffic congestion, and environmental benefits—relative to today’s most popular new sequential mobility options. At the same time that innovative mobility services are being enthusiastically embraced by tech-savvy travelers, they do raise public policy issues. For example, those without credit accounts and smartphones cannot access many of these new services, and helmet requirements may increase safety, but can discourage bikesharing. The most controversial new services to date are clearly TNCs, which are growing rapidly in popularity, spreading to cities around the globe, disrupting the regulated for-hire taxi industry, and posing a series of challenges to transportation and regulatory policy makers.

A közúti közlekedés automatizálása felé. Állami – magán együttműködési lehetőségek. A 3. EU-U.S. Közlekedési Kutatási Szimpózium összefoglalója 2015.
Towards Road Transport Automation. Opportunities in Public–Private Collaboration. Summary of the Third EU-U.S. Transportation Research Symposium 2015.
Szerző(k): U.S. Department of Transportation
Transportation Research Board, USA
European Commission

Terjedelem: 108 oldal

This document summarizes the symposium Towards Road Transport Automation: Opportunities in
Public–Private Collaboration, which was held April 14 and 15, 2015, at the National Academy of
Sciences Building in Washington, D.C. The 2-day, invitation-only symposium brought together high-level experts to share their views on the future of surface transport automation from the technological and socioeconomic perspectives. Recognizing the importance of the emerging transport automation ecosystem, participants came from public agencies, the automotive and technology industries, academia, consulting firms, and other groups key to implementation of road transport automation.
A bilateral planning committee was assembled by TRB and appointed by the National Research Council to organize and develop the symposium program. The planning committee was responsible for organizing the symposium, identifying speakers, commissioning two white papers, and developing three use case scenarios on road transport automation to facilitate discussion. The white papers and the use case scenarios are provided as appendixes. New readers may find it advantageous to review these appendixes first to more fully understand the discussion in the breakout groups. The three use case scenarios—freeway platooning, automated city center, and urban chauffeur—were developed by the planning committee to help frame discussions in the breakout groups. The scenarios highlight potential applications at different levels of automation that serve different market segments and user groups and that reflect different implementation time frames. The breakout group discussions focused on identifying issues, opportunities, and research topics appropriate for EU-U.S. collaboration.

Az időérték és a megbízhatóság értékének meghatározása különleges használatú sávokon
Investigating the Value of Time and Value of Reliability for Managed Lanes
Szerző(k): Jin, X., Hossan, M.S., Asgari, H. Florida International University, USA

Terjedelem: 91 oldal

This report presents a comprehensive study in Value of Time (VOT) and Value of Reliability (VOR) analysis in the context of managed lane (ML) facilities. Combined Revealed Preference (RP) and Stated Preference (SP) data were used to understand travelers’ choice behavior regarding the usage of MLs. The data were obtained from the South Florida Expressway Stated Preference Survey conducted by the Resource Systems Group, Inc. (RSG), which gathered information from automobile drivers of South Florida who had recently made a trip on I-75, I-95, or SR 826 corridors. Various modeling and analysis approaches were employed to further reveal user heterogeneity in VOT and VOR. Mixed logit modeling was applied and indicated an average value of $9.41 per hour for VOT and $13.02 per hour for VOR. The model was further enhanced by adding interaction effects of variables, which helped recognize and quantify potential sources of heterogeneity in user sensitivities to time, reliability and cost. The sensitivities were employed to capture the user heterogeneity in VOT and VOR. The findings indicated that various socioeconomic demographic characteristics and trip attributes contributed to the variations in VOT and VOR at different magnitudes. This study provides a robust approach to quantify user heterogeneity in VOT and VOR by incorporating the corresponding interaction effects for specific market segments. The results of this study contribute to a better understanding on what attributes lead to higher or lower VOT and VOR and to what extent. These findings can be incorporated into the demand forecasting process and lead to better estimates and enhanced analytical capabilities in various applications, such as toll feasibility studies, pricing strategy and policy evaluations, and impact analysis, etc.

Képfeldolgozáson alapuló olcsó megoldás burkolathibák automatikus észlelésére, helyhez rendelésére és minősítésére
An Inexpensive Vision-Based Approach for the Autonomous Detection, Localization, and Quantification of Pavement Defects
Szerző(k): Becerik-Gerber, B., Masri, S.F., Jahanshahi, M.R. University of Southern California, Purdue University, USA

Terjedelem: 45 oldal

This project involves developing a cost-effective, vision-based sensor system for autonomous data acquisition of road surface conditions and for autonomous detection, localization, and quantification of pavement defects. The proposed sensor system provides a large array of information such as vision, depth, inertial, and positioning information, which can be efficiently used for detecting and localizing defects on pavements, on an offline basis, at a lower cost. The sensor system can be used periodically to gather data that can be maintained in a main server. The proposed system provides useful pavement defect information at a fraction of the cost of an advanced sensor system. The cost, ease of use, and computational aspects of this project offer unique benefits for the data acquisition and monitoring of pavement surfaces. The sensor system can be mounted on a variety of public and private vehicles. This provides continuous and long-term information that can be used for data analytics. Furthermore, increased data gathering can provide an improved understanding of the formation and evolution of defects in time. This can also lead to earlier measures to curtail the degradation of the pavement surface. The proposed technology is ideal for small cities and counties. In this report, the results of the project are described in three stages. Work in stage I focused on the results of the design and development of the hardware and software modules. The hardware module included the selection of suitable depth cameras, accelerometers, and an Inertial Navigation System (INS). The software module consisted of the data and hardware synchronization schema, and color and depth camera calibration. In stage II, field tests and data analysis were performed. In the third part of this report, the results of the pavement crack segmentation algorithm are discussed.

A gyalogosok átkelési sebességének és idejének felülvizsgálata a gyalogos átkelőhelyeken
A Review of Pedestrian Walking Speeds and Time Needed to Cross the Road
Szerző(k): Crabtree, M., Lodge, C., Emmerson, P.
Transport Research Laboratory, UK

Terjedelem: 40 oldal

Living Streets has commissioned the Transport Research Laboratory (TRL) to undertake research to consider the appropriateness of the current method of calculating the time needed for pedestrians to cross a road at signal controlled pedestrian crossings both stand alone and at junctions. One aspect that has been highlighted as a potential problem many times over the years, but not acted upon in any substantive way in the UK, is the time required for pedestrians to cross the road at either a pedestrian facility at a signal controlled junction, or at stand-alone signal controlled pedestrian crossings. This report considers the need for and the implications of changing the signal timings to allow pedestrians more time to cross.

A vasúti személyközlekedés energia felhasználásának összevetése más versengő közlekedési módokkal
Comparison of Passenger Rail Energy Consumption with Competing Modes
Szerző(k): TranSys Research Ltd., CPCS Transcom, Lawson Economics Research Inc., Canada
RailTEC, University of Illinois, USA

Terjedelem: 208 oldal

NCRRP Report 3: Comparison of Passenger Rail Energy Consumption with Competing Modes provides a comprehensive model that allows the user to compare the energy consumption and greenhouse gas (GHG) emissions of intercity and commuter passenger rail with those of competing travel modes along a designated travel corridor. This report summarizes the research used to develop the model and presents a set of case study applications.

Új generációs híd menedzsment eszközök és hídvizsgálat
Next Generation Bridge Management Tools and Inspection
Szerző(k): Bektas, B.A.
Terjedelem: 47 oldal

The objectives of this research were twofold. The first objective was to identify the needs for the inspection methodology, manuals, training, and the timetable needed for all bridge owners to start collecting element level bridge inspection data. The second objective was to identify how to incorporate this new inspection methodology into the rich reporting tools and performance measures that the Minnesota Department of Transportation (MnDOT) uses for determining the bridge projects in the annual program. Working with the MnDOT Bridge Office, the research team identified the necessary changes to the bridge inspection elements that would both ensure MnDOT conforms to the new American Association of State Highway and Transportation Officials (AASHTO) Guide Manual for Bridge Element Inspection and provide the necessary data for the agency’s bridge management process. The changes needed for MnDOT’s Bridge Replacement and Improvement Management (BRIM) were also identified working with the MnDOT Bridge Office.

Hozzáférés a járműben tárolt adatokhoz és információkhoz
Access to in-vehicle resources and data
Szerző(k): C-ITS Platform Working Group 6, EU

Terjedelem: 21 oldal

The increasing connectivity and digitisation of vehicles is currently changing the automotive industry landscape. Specific data that were previously accessed via a physical connection in the vehicle are now more and more accessible remotely. Independently of the model/solution retained to give access to in-vehicle data and resources, the main objective should be to allow customers the freedom to choose which service they desire, meeting their specific needs, in order to ensure open choice for customers. This goes through an open and undistorted competition for the provision of these services.

A közútfenntartás szakmunkásainak képzése és bizonyítványa
Training and Certification of Highway Maintenance Workers
Szerző(k): Laffey, N., Zimmerman, K.A. Applied Pavement Technology, Inc., USA
Terjedelem: 152 oldal

This synthesis documents front-line maintenance worker training and certification practices for highway transportation agencies in the United States and Canada. The information presented includes the types of topics being addressed by training and certification programs, the delivery methods used to provide the training, the sources of instruction, and whether material-sharing relationships are being utilized to access training. In addition, the synthesis captures how training is related to performance and the incentives being used by state and provincial agencies to encourage front-line maintenance workers to complete training. Information used in this study was gathered through a literature review and a survey of state departments of transportation and Canadian provincial transportation agencies.
Follow-up interviews with selected agencies provided additional information.

Laboratóriumi és terepi aszfaltbeton minták volumetrikus és mechanikai tulajdonságainak összehasonlítása
Comparing the Volumetric and Mechanical Properties of Laboratory and Field Specimens of Asphalt Concrete
Szerző(k): Mohammad, L.N., Elseifi, M.A., Cooper, III, S.B., Hughes, C.S., Button, J.W.,
Dukatz, Jr., E.L.
Louisiana State University, USA

Terjedelem: 134 oldal

Mix properties that deviate appreciably from design during the production and construction of asphalt mixtures often lead to premature pavement distress or even failure. The objective of this project was to quantify sources and causes of variability in the measurements of volumetric and mechanical properties of dense-graded asphalt mixtures for three types of specimens that may be encountered during design (LL), production (PL), and construction (PF). In addition, the impacts of variation among specimen types on pavement performance prediction were evaluated. This was accomplished by evaluating common volumetric and mechanical properties of the three specimen types [design
(LL), production (PL), and construction (PF)] from a nationwide compilation of 11 mixtures from various states throughout the United States. Variations in key production process factors – specifically the return of baghouse fines, delay in specimen fabrication, aggregate absorption, aggregate hardness, and stockpile moisture content – were evaluated in this study. For each mixture, the following volumetric and mechanical properties were evaluated for the three specimen types: Volumetric properties: air voids, voids in the mineral aggregate, voids filled with asphalt, aggregate bulk specific gravity, mixture maximum specific gravity, asphalt binder content, and gradation. Mechanical properties: loaded wheel tracking (LWT) rut depth, axial dynamic modulus, and indirect tension
(IDT) dynamic modulus.


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