Required navigation performance for connected and autonomous vehicles: where are we now and where are we going?

ABSTRACT

While automotive original equipment manufacturers and IT companies are developing and demonstrating self-driving cars, true autonomy will not be realised in the near future due in part to the technology readiness level of the existing systems as well as issues of ethics, security, governance and standards surrounding the implementation of autonomy for road transport. However, advances in cellular phones and networks, satellite-based positioning and communications, cloud computing, combined with a rise in the volumes of available data, allied with a reduction in their costs, offer the very real possibility of connecting vehicles, one to another and to smart city infrastructure as part of the Internet of Things (IoT). Data from connected vehicles, when combined with other information, may provide valuable intelligence to traffic managers and other stakeholders via cooperative intelligent transport system (C-ITS) platforms. Nevertheless, many issues face the implementation of a truly connected IoT in general and C-ITS in particular.     

Financing local rural road maintenance. Who should pay what share and why?

The benefits from minor rural road infrastructure can be very individual, when a road is important for reaching a (group of) farm(s), serving little or no inter-local traffic. Rural road maintenance therefore asks for a specific taxation model that distributes costs according to benefits involved for the individual taxpayer. The distribution of maintenance costs among taxpayers used by local governments is often poorly founded. A new model was developed for two local road maintaining governments in the Netherlands. In essence, the model emphasises that the basic facilities for reaching buildings and parcels along a road should be paid by the rural real estate owners. Extra facilities (like additional pavement width and plantings) enable inter-local traffic. Therefore, maintenance of these extra facilities should be paid by all inhabitants of the community. This article describes, in detail, the model used and the resulting cost distribution, among others in relation to the definition of `basic facility'. We compare these results with the cost distribution of comparable authorities and conclude that the model offers a logical and clear calculation of who pays what share and why. The model might also facilitate taxing the costs of road maintenance, in a broader sense, for a wide range of areas and governmental organisations.     

Are we ready to embrace connected and self-driving vehicles? A case study of Texans

While connected, highly automated, and autonomous vehicles (CAVs) will eventually hit the roads, their success and market penetration rates depend largely on public opinions regarding benefits, concerns, and adoption of these technologies. Additionally, the introduction of these technologies is accompanied by uncertainties in their effects on the carsharing market and land use patterns, and raises the need for tolling policies to appease the travel demand induced due to the increased convenience. To these ends, this study surveyed 1088 respondents across Texas to understand their opinions about smart vehicle technologies and related decisions. The key summary statistics indicate that Texans are willing to pay (WTP) $2910, $4607, $7589, and $127 for Level 2, Level 3, and Level 4 automation and connectivity, respectively, on average. Moreover, affordability and equipment failure are Texans’ top two concerns regarding AVs. This study also estimates interval regression and ordered probit models to understand the multivariate correlation between explanatory variables, such as demographics, built-environment attributes, travel patterns, and crash histories, and response variables, including willingness to pay for CAV technologies, adoption rates of shared AVs at different pricing points, home location shift decisions, adoption timing of automation technologies, and opinions about various tolling policies. The practically significant relationships indicate that more experienced licensed drivers and older people associate lower WTP values with all new vehicle technologies. Such parameter estimates help not only in forecasting long-term adoption of CAV technologies, but also help transportation planners in understanding the characteristics of regions with high or low future-year CAV adoption levels, and subsequently, develop smart strategies in respective regions.     

What do people know about their public transport options?

This paper studies the memory representations of residents regarding the public transport system in their city. Telephone interviews were conducted with a representative sample of 204 inhabitants in a selected residential inner-city area in Stockholm. Route knowledge questions, recognition tasks, free-recall tasks and estimations of service frequency were used to explore memory representations. The results showed that, in general, residents in metropolitan areas have good knowledge of the public transport options along well-known transport corridors. The memory representation of lesser-known transport corridors tends to be of a poorer quality. In the results presented here, the variables gender, age, employment status, level of education and car availability had no correlation with the quality of the memory representation, but experience increased knowledge. Although frequent users of public transport had a more detailed representation of the system, the less frequent users also had a considerable- and good-memory representation. An explorative hierarchy for representation of public transport lines in the memory is proposed. It is hypothesised that memory representations of a transport line can be affected by the following three factors: the extent to which a line is visible in the urban area, the straightness of the routes and whether or not stops are labelled, for example, by destination area. Simply put, these factors determine how well a person knows a line. It was found that people first remember a commuter train and a trunk bus line, followed by metro lines and suburban buses and finally normal inner-city buses with the poorest anchorage in memory.

How will we fund our roads? A case of decreasing revenue from electric vehicles

Annual expenditures for transportation infrastructure have recently surpassed the funding available through tax and fee collection. One large source of revenue generation for transportation infrastructure is use fees that are charged through taxes on gasoline both on a federal and state level. A massive adoption of electric vehicles (EVs) in the United States would result in significantly lower gasoline consumption and thus reduce the revenue collected to maintain the U.S. transportation infrastructure. We investigate how different vehicles will change the annual fee collected on a marginal basis. In addition, we assess the effects of adoption of alternative vehicles on revenues using several projections of alternative vehicles adoption, both on a state-by-state basis and at the national level. We find that baseline midsize and compact vehicles such as the Toyota Camry and Honda Civic generate approximately $2500–$4000 in tax revenue over their lifetime. Under the current funding structure, battery-electric vehicles (BEVs) such as the Nissan Leaf generate substantially less at $400–$1300, while plug-in hybrid electric vehicles (PHEVs) such as the Chevrolet Volt generate $1500–$2700. Even in states with high lifetime fees due to fuel taxes, such as California, revenue generation can be upwards of 50% lower than in states with high registration fees such as Colorado. Total annual revenue generation decreases by about $200 million by 2025 as a result of EV adoption in our base case, but in projections with larger adoption of alternative vehicles could lead to revenue generation reductions as large as $900 million by 2025. Potential schemes that charge user fees on alternative fuel vehicles to overcome the decrease in revenue include a flat annual registration fee at 0.6% of the vehicle’s manufacturer suggested retail price (MSRP) or 2

per mile fee.     

How can we alter our carbon footprint? Estimating GHG emissions based on travel survey information

The city of Montreal has taken recent initiatives to significantly reduce overall greenhouse (GHG) emissions from the transport sector and has made large investments in alternative transportation. In particular, the city has called upon the participation of all businesses and institutions to further these goals. In light of these recent plans, this study identifies with two objectives: first, to develop a methodology for estimating GHG emissions generated by commuters to McGill University’s downtown campus; and secondly, to better understand who, how, and when each commuter to McGill generates travel-related GHG. Mode split, travel distance, age, gender and job category were uncovered by a 2011 travel survey that we conducted across the University, from which daily individual GHG emissions are estimated. Details about these trips not only reveal who the largest polluters are and where they are coming from, but also the seasonality of their emissions. These associations are then used to narrate scenarios which present alternatives to the structure of individuals’ commutes by examining the outcomes of selected shifts in travel behavior on total GHG emissions.     

All work and no play? The role of instrumental and affective factors in work and leisure journeys by different travel modes

This paper examines the relative importance that people attach to various instrumental and affective journey attributes when travelling either for work or for a leisure day trip and presents how journeys by various travel modes score on these attributes. Although not a comparative paper, data are presented for two studies which used some identical measurements: one on commuter journeys and one on leisure journeys. The results show that for work journeys, respondents tend to attach more importance to instrumental aspects, and especially to convenience than to affective factors. For leisure journeys, however, respondents appear to attach almost equal importance to instrumental and affective aspects, particularly flexibility, convenience, relaxation, a sense of freedom and ‘no stress’. Each study also examines (i) how regular users’ evaluate their own mode and (ii) how car users perceive the performance of alternative modes compared to their importance ratings. This ‘gap’ analysis reveals on which modes and for which attributes the greatest deficiencies in performance lie. The data for both the work and leisure studies shows that for car users, alternative transport modes are inferior on the salient attributes such as convenience and flexibility even though car users rate modes such as walking and cycling as performing well, if not better, on less important attributes such as the environment, health and even excitement. Nevertheless, for those who cycle and walk regularly, satisfaction with their own travel mode as measured by the gap between importance and performance on salient attributes is better than for those who mostly use the car. Conclusions are made as to how greater attention to affective factors may improve our understanding of mode choice.     

Intelligent transportation system and traffic safety – drivers perception and acceptance of electronic speed checkers

Intelligent Transportation System (ITS) can play an important role in reducing risks and increasing traffic safety. Discussion as to whether a technological approach or a behavioral approach is the right way to achieve a safer traffic environment forms a point of departure for this paper. On the one hand, there are the technicians who emphasize technology as the way towards safer traffic. Behaviorists, on the other hand, view the drivers’ behavior as fundamental and argue that education and incentive-oriented policies are essential in order to influence the driver and therefore increase traffic safety. Independent of the approach advocated a successful outcome of either a technological improvement, or an information campaign, has to be based on a high level of acceptance among potential users. In order to increase traffic safety, it is therefore essential to recognize driver motivation and attitudes. In this paper we focus on drivers’ attitudes towards risk, traffic safety and safety measures. A study of drivers’ attitudes and acceptance of an electronic device for speed checking (which the drivers tested for nine months) indicated a high acceptance level. The drivers perceived that they had both become more aware of traffic regulations and behaved in accordance with safety regulations.     

Bicycling renaissance in North America? An update and re-appraisal of cycling trends and policies

This paper reviews trends in cycling levels, safety, and policies in Canada and the USA over the past two decades. We analyze aggregate data for the two countries as well as city-specific case study data for nine large cities (Chicago, Minneapolis, Montréal, New York, Portland, San Francisco, Toronto, Vancouver, and Washington). Cycling levels have increased in both the USA and Canada, while cyclist fatalities have fallen. There is much spatial variation and socioeconomic inequality in cycling rates. The bike share of work commuters is more than twice as high in Canada as in the USA, and is higher in the western parts of both countries. Cycling is concentrated in central cities, especially near universities and in gentrified neighborhoods near the city center. Almost all the growth in cycling in the USA has been among men between 25-64 years old, while cycling rates have remained steady among women and fallen sharply for children. Cycling rates have risen much faster in the nine case study cities than in their countries as a whole, at least doubling in all the cities since 1990. They have implemented a wide range of infrastructure and programs to promote cycling and increase cycling safety: expanded and improved bike lanes and paths, traffic calming, parking, bike-transit integration, bike sharing, training programs, and promotional events. We describe the specific accomplishments of the nine case study cities, focusing on each city’s innovations and lessons for other cities trying to increase cycling. Portland’s comprehensive package of cycling policies has succeeded in raising cycling levels 6-fold and provides an example that other North American cities can follow.     

Experimental and Numerical Study on the Behaviors of Deep-Buried Water-Storage and Drainage Shield Tunnels北大核心CSCD

Deep-buried water-storage and drainage shield tunnels, which are different from road and subway shield tunnels in terms of computation theory, construction technology and operation maintenance, would bear high inner water pressure and large earth pressure. In view of the change of the bearing mode for the lining structure of water-storage and drainage shield tunnels, a full-ring test and numerical analysis are carried out to study the influence of inner water pressure, staggered joint assembly and bolt installation types on the behaviors of water-storage and drainage shield tunnels. The results show that the deformation of the straight-jointed water-storage and drainage shield tunnel varies greatly from the state of empty water to that of full water; and the vertical and horizontal convergence deformations of the tunnel with inner water pressure of 0.6 MPa are 2.2 times and 3.2 times of that without inner water pressure, respectively. The convergence deformation, and the maximum joint opening and bolt tension of stagger-jointed lining structure decrease by 15%-25% and 25%- 40%, respectively, compared with that of the straight-jointed water-storage and drainage shield tunnel. The bolts at the segmental joints will yield because of the increase of inner water pressure and the first occurrence of bolt yield phenomenon is located near the position on the lining structure which is under the action of maximum negative bending moment; because the failure of shield tunnel is always caused by the yield of joint bolts, this position is the weak point for the deep-buried water-storage and drainage shield tunnel. For the water-storage and drainage shield tunnel based on the connection with double rows of bolts, the bolts near the outer arc surface of segmental joints in the area of 90 degree in the vault and arch bottom can be removed; the bolts near the inner arc surface of the segmental joints within the 90 degree of the haunch must be installed, otherwise, the tensile force of the bolts at the segmental joint near the maximum negative bending moment will increase by 5%-14%. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

Disaggregate demand models—Promises and prospects

For nearly two decades it has been recognised that there are serious deficiencies in the traditional aggregate modelling approach to travel demand analysis. It was hoped that many, if not all, of these deficiencies would be overcome through the development of disaggregate models. Yet nearly 10 years after some of the first major research projects, it has been suggested that they have not yet been successfully applied in any major planning study. There can be little doubt that disaggregate model techniques do offer the scope for major improvements over aggregate models, yet there would seem to be a growing groundswell of doubt about their ability to live up to the expectations which were cultivated during the early '70s. The crucial question to most of those concerned with planning and policy development is, even if disaggregate models are not the panacea many of us hoped them to be, whether they can still improve our forecasting ability, or not.     

Severity of injury resulting from pedestrian–vehicle crashes: What can we learn from examining the built environment?

This paper examines the impact of personal and environmental characteristics on severity of injuries sustained in pedestrian–vehicle crashes using a generalized ordered probit model. The data covers 2000–2004 of pedestrian–vehicle crashes taken from police incident reports for Baltimore City and supplemented with local land use, urban form and transportation information specific to the individual crash locations. The results on personal and behavioral variables confirm previous findings. Women pedestrians involved in crashes tend to be injured less frequently than their male counterparts; children have an increased likelihood of sustaining injuries and older persons are more likely to be fatally injured. Pedestrians who cross against the traffic signal, are not in a crosswalk and are involved in a crash after dark are associated with greater injury risk. Of the built environment policy variables of interest, transit access and greater pedestrian connectivity, such as central city areas, are significant and negatively associated with injury severity. These results suggest that the environmental conditions should be given more scrutiny and be an important consideration when evaluating and planning for pedestrian safety.     

Design and Construction HSL Immersed Tunnels in Holland

Currently, two immersed tunnels are being constructed in Holland as part of a high speed railway link. Designing and building these two tunnels was a challenge due to a combination of factors: Technical specifications with small tolerances, which are never encountered before in Holland, poor soil conditions and a short construction period had to be managed.Some major aspects will be explained in this paper.     

Q-analysis and transport: A false start?

The utility for transport research of a number of key ideas from the methodology of Q-analysis is critically evaluated in this paper. It is argued through discussion of specific features of the approach that the literature on this subject has considerably overstated its utility, and that there has been a neglect of alternative methods that could achieve some of the desired ends.     

Transportation and land-use preferences and residents’ neighborhood choices: the sufficiency of compact development in the Atlanta region

This paper analyzes the transportation and land-use preference and actual neighborhood choices of a sample of 1,455 residents of metro Atlanta. We develop a stated-preference scale on which desires for neighborhood type are gauged, from preferences for low-density, auto-oriented environments to desires for compact, walkable, and transit-oriented neighborhoods. This scale is then related to desires for change in one’s own neighborhood characteristics after a hypothetical move. If all neighborhood preferences were equally likely to be satisfied, then neighborhood preferences would not be correlated with a desire for change. By contrast, in the current study, stronger preferences for a more walkable environment are associated with greater desire for change in one’s neighborhood characteristics. This suggests an undersupply of compact, walkable, and transit-friendly neighborhood types relative to current demand.

Control of vehicle ownership and market competition: theory and Singapore’s experience with the vehicle quota system

This paper studies the impact of vehicle quota system on the market structure of Singapore’s car distributorship industry. Using recently available data, we analyzed the populations and new registrations of different brands of passenger car and motorcycle. We found an increase in market concentration in the car distributorship industry, as the market shares of the top distributors have increased steadily, even though the annual growth rate of vehicle population is capped at 3% per annum. We also found that average dealership markups for passenger cars for the period August–September 2002 are similar to those reported in earlier studies. We relate these empirical findings to a theoretical model of a differentiated-good oligopoly operating under an industry sales constraint.     

PPPs — True Financial Costs and Hidden Returns

The cost of using private finance is at the centre of the public private partnerships (PPPs) debate, but until now most works considered only the direct financial costs such as the loan interest rate and the shareholders return on equity and were based on various secondary sources. This paper focuses on seven shadow toll deals closed in Portugal between 1999 and 2002 and reports the financial costs of the PPP model considering also the associated transaction costs and is based on detailed information included in each concession's financial base case. The transaction costs include financial costs such as banking fees, due diligence costs and the impact of all cash distribution traps, such as reserve accounts or minimum-level of debt ratios. The PPP financial costs were then compared with the costs arising from raising public debt through a government or a public agency bond. Our analysis shows that the PPP ‘true' financing costs are, on average, 370 basis points above the cost of raising public debt and that the ‘transaction costs' account for around 40% of that financial premium.     

E‐Shopping and its Relationship with In‐store Shopping: Empirical Evidence from the Netherlands and the USA

Abstract

Despite considerable examination of the impact of telecommunications on travel, little empirical evidence sheds light on the impact of e‐shopping on travel—a recent and increasingly popular form of telecommunications. This paper analyses determinants of online buying and their relationship with in‐store shopping, using empirical data obtained from Minneapolis, USA, and Utrecht, the Netherlands. Based on chi‐square tests and logistic and ordinary least‐squares regressions, the results indicate that online buying is affected by sociodemographics and spatial characteristics of people, their Internet experience, and their attitudes towards in‐store shopping. US respondents who prefer to see products in person are less likely to buy online. Dutch respondents are more likely to buy online as travel times to shops are shorter. At first sight, this counterintuitive result might be related to an urban, innovative lifestyle that supports e‐shopping. A more detailed analysis of Dutch online buyers reveals that they make more shopping trips than non‐online buyers and have a shorter shopping duration. The results indicate that the relationship between online buying and in‐store shopping is not one of substitution but of complementarity.