The rider's impression of a simulated trip by PRT

The potential user interest in PRT's and the conditions for their use were studied. As users are unable to express certain opinions about technology they don't know, assessment studies must be close to real life. One way to getting close to reality is through studies in Virtual Reality (VR). Passenger encounters with PRT was studied by in-depth interviews directly after a VR-simulated trip in a real vehicle. The aims of using VR-technology seems to have been achieved. Many of the subjects had the impression of a real trip, some of them also of having travelled high above ground. All subjects were in favour of PRT and thought they would utilize it. They had confidence in the automatic control devices, although they wanted more information and better design of the safety system. The greatest conflict was the encroachment on the cityscape. Many of the subjects did not accept the impact of the guideways on the old city environment. However these views contrast with the desired accessibility.     

The morgantown PRT: It is still running at West Virginia University

It has been over fifteen years since the Morgantown PRT system went into passenger service. Its start was marked by cost overruns, high operating costs and poor reliability. However over time, these initial problems and difficulties have been overcome, and today the system provides an extremely important and reliable service that links downtown Morgantown with three campuses of West Virginia University. It is still running. This paper provides background on the development of the system and current operating characteristics of this famous transit demonstration project.     

Distributed algorithm for empty vehicles management in personal rapid transit (PRT) network

In this paper, an original heuristic algorithm of empty vehicles management in personal rapid transit network is presented. The algorithm is used for the delivery of empty vehicles for waiting passengers, for balancing the distribution of empty vehicles within the network, and for providing an empty space for vehicles approaching a station. Each of these tasks involves a decision on the trip that has to be done by a selected empty vehicle from its actual location to some determined destination. The decisions are based on a multi‐parameter function involving a set of factors and thresholds. An important feature of the algorithm is that it does not use any central database of passenger input (demand) and locations of free vehicles. Instead, it is based on the local exchange of data between stations: on their states and on the vehicles they expect. Therefore, it seems well‐tailored for a distributed implementation. The algorithm is uniform, meaning that the same basic procedure is used for multiple tasks using a task‐specific set of parameters. Copyright © 2016 John Wiley & Sons, Ltd.     

The case for heterodoxy in longitudinal analysis

Longitudinal analysis should be developed with the prime objective of discovering the characteristics of dynamic, disequilibrium processes. This will require a range of different research methods, including qualitative social research, repeated cross-section surveys, panel surveys, aggregate time series analysis, and simulation models. In each case it is essential that models should be formulated in a dynamic way (e.g. with lags, inertia and asymmetry). Examples are given of work using each of these methods, applied to the analysis of habit, aging, market volatility, turnover, long-term demand elasticities, and forecasting using demographic information.     

The simple,efficient, elegant,and effective model (SE3M) of land use and transportation

Integrated land use/transportation forecasting models add significant policy and infrastructure alternatives analysis capabilities to the urban planning process. Historically, the financial, time, and staff requirements to develop one of these models has put them beyond the reach of most small- to medium-sized urban areas. The purpose of this paper is to present the large zone economic submodel of SE³M, an integrated model – founded upon economic base theory and bid-rent theory – that is reasonably accurate, yet simpler in form, function, and implementation than competing models. The US territory of Guam is used as the case study/proof of concept implementation for this model framework. The submodel presented here was validated against a horizon year with known data for zonal level population and employment totals together with control totals for the island as a whole. The model was able – across two base years and one validation, horizon year – to locate all jobs and a high percentage of the population on each zone on the island.     

The Bid-rent Land Use Model of the simple,efficient, elegant,and effective model of land use and transportation

Integrated land use/transportation forecasting models add significant policy and infrastructure alternatives analysis capabilities to the urban planning process. The financial, time, and staff requirements to develop these models has put them beyond the reach of most small to medium sized urban areas. This paper presents the land use allocation submodel of the Simple, Efficient, Elegant, and Effective model of land use and transportation (SE³M), an integrated land use and transportation forecasting model founded upon Economic Base Theory and Bid-rent Theory. The Bid-rent Land Use Model (BLUM) is an agent based, spatial competition model utilizing unique utility curves for willingness to pay and incomes for budget constrained abilities to pay for each agent. The model structure, estimation, calibration, implementation, and validation are presented. With a single year of land use data available, the validation approach used the Kappa Index of Agreement to spatially check model outputs against base year control data while controlling for agreement by chance. The U.S. territory of Guam is used as the case study/proof of concept implementation for this model framework. Once calibrated, BLUM could solve the spatial competition problem on Guam in less than two minutes of processing time with over 90% accuracy.     

Transport policy for London in 2001 The case for an integrated approach

The paper reports the results of a series of studies conducted to enable the London Planning Advisory Committee to provide advice on strategic transport policy for London. The analytical approach combined the use of an area-based, multi-modal strategic model (LAM) and professional judgment. The performance of LAM as a basis for providing rapid advice on complex issues in transport policy is assessed.The resulting policy advice advocated a coherent approach, involving new infrastructure, particularly for rail; improved management of the road and public transport networks; the use of subsidy to enhance public transport service levels; and road user charges to reduce the impact of private vehicles on congestion and the environment. Road user charges emerged as the pivotal issue in the policy; the paper discusses their role, and the questions which still need to be resolved before they can be implemented.The main message of the study is that no one element of transport policy can tackle London's problems alone; an integrated policy in which infrastructure provision, management and pricing are used to complement one another is shown to be far more effective.     

Interactions between driver information,route choice,and optimal signal timing on a simple network

The interaction between driver information, route choice, and optimal traffic signal settings was investigated using a simple two-route system with a single “T” intersection and a fixed O-D demand. The logit model and the method of successive averages (MSA) were used to calculate the route choice probabilities and the stochastic equilibrium assignment. Given an assignment, signal settings which minimized average intersection delay were calculated; flow reassignment and new optimal signal settings were then obtained and this iterative process continued until convergence. The calculations were performed either directly in a combined assignment/signal optimization model or in stages using the output flows of an assignment model as inputs to TRANSYT-7F and iterating between the two models. Results show that a unique joint signal timing/assignment equilibrium is reached in all cases provided that a certain precision in drivers' perceptions is not reached. If driver information increases to this precision (bifurcation point) and beyond, results show clearly that the unique joint signal timing/assignment equilibrium no longer exists. In fact, three joint equilibria points exist after the bifurcation point. Two of these points are stable and one is not. It was found that the system yields the lowest total intersection delay when the joint equilibrium is such that all traffic and hence the major part of green time is assigned to only one of the two routes. Although this may not be feasible to implement in practice, the results indicate clearly for this simple example that there is a trade-off between a system with minimum total delay but no unique joint signal-settings/assignment equilibrium (achieved when drivers have nearly perfect information about the system) and a system with a unique joint equilibrium but with higher total delay (achieved when drivers have reasonably good but somewhat limited information). In most cases the second system seems appropriate for a number of practical reasons.     

Attitudinal models of modal choice: The multinomial case for selected nonwork trips

Attitudinal multinomial logit models of modal choice are presented for four nonwork activities: major grocery shopping, shopping for odds and ends, shopping for personal goods and visiting friends and acquaintances. Explanatory variables are individuals' beliefs about attributes of four modal alternatives: bus, car, taxi and walking. Factor analysis is employed to identify latent dimensions of perception of the modal alternatives and to eliminate problems of multicollinearities in model estimation. Models are estimated using data obtained for a sample of residents of Buffalo, New York. Planning implications of the methodology are assessed.This author is presently Systems Planner with Applied Resource Integration, Ltd., Boston, Massachusetts.     

Trial and error method for optimal tradable credit schemes: The network case

Recent studies on the new congestion reduction method―tradable credit scheme rely on the full information of speed‐flow relationship, demand function, and generalized cost. As analytical travel demand, functions are difficult to establish in practice. This paper develops a trial and error method for selecting optimal credit schemes for general networks in the absence of demand functions. After each trial of tradable credit scheme, the credit charging scheme and total amount of credits to be distributed are updated by both observed link flows at traffic equilibrium and revealed credit price at market equilibrium. The updating strategy is based on the method of successive averages and its convergence is established theoretically. Our numerical experiments demonstrate that the method of successive averages based trial and error method for tradable credit schemes has a lower convergence speed in comparison with its counterpart for congestion pricing and could be enhanced by exploring more efficient methods that make full use of credit price information. Copyright © 2013 John Wiley & Sons, Ltd.     

The role of public transport for feasibility and acceptability of congestion charging – The case of Stockholm

In the Stockholm Trial, congestion charges and the expansion of public transport services were closely linked together in marketing efforts, as well as in political decisions. In this paper, we analyse the role that public transport may have played in increasing acceptability and feasibility of the scheme. We study four aspects of the relationship between charging and public transport provision: (i) the initial modal share, (ii) contribution to modal shift (iii) compensation to losers (iv) revenue hypothecation. Our analyses, based on a combination of primary and secondary data, support the hypothesis that public transport contributed to the successful implementation of congestion charging in Stockholm through all those four mechanisms.     

Improving urban traffic flow by restraint of traffic: The case of Lagos,Nigeria

Traffic restraint techniques, widely used to combat traffic congestion in the developed countries, have been tried in Lagos, Nigeria. This paper examines the impact of the use of odd and even numbered vehicles on alternate days in reducing congestion on the urban roads. The result of the analysis indicates that the restraint technique worked only during the first few months of its introduction. The basic causes of the subsequent failure are outlined and possible solutions suggested.     

Impacts of freeway accidents on CO2 emissions: A case study for Orange County,California, US

Traffic congestion caused by traffic accidents contributes to CO₂ emissions. Generally, more efficient and prompt responses to accidents lead to reduced traffic congestion as well as CO₂ emissions. Here we assess the CO₂ emissions impacts of freeway accidents, applies an existing model to capture spatio-temporally congested regions caused by freeway accidents. A case study for the assessment of CO₂ emissions impacts of based on the results from the model is presented.     

Integrated modeling framework for leasing urban roads: A case study of Fresno,California

Increasing private sector involvement in transportation services has significant implications for the management of road networks. This paper examines a concession model’s effects on a road network in the mid-sized city of Fresno, California. Using the existing transportation planning models of Fresno, we examine the effects of privatization on a number of typical system performance measures including total travel time and vehicle miles traveled (VMT), the possibility of including arterials, and the differences between social cost prices and profit maximizing prices. Some interesting insights emerge from our analysis: (1) roads cannot be considered as isolated elements in a concession model for a road network; (2) roads can function as complements at some levels of demand and become substitutes at other levels; (3) policy makers/officials should consider privatizing/pricing arterials along with privatizing highways; (4) temporally flexible but limited price schedule regulations should be part of leasing agreements; and (5) non-restricted pricing may actually worsen system performance, while limited pricing can raise enormous profits as well as improve system performance.     

Map-induced journey-planning biases for a simple network: A Docklands Light Railway study

A usability study was conducted to identify the most effective prototype Docklands Light Railway map for installation on trains. This comprised a series of tasks that required station finding and also planning of routes between pairs of stations, with response time and accuracy as measures of performance. In addition, subjective ratings of map design were collected via questionnaire-based evaluations, and also ranked preferences between designs. A clear best-option was easily identifiable as a result of this research. The existing design was associated with the most journey planning errors, and two of the prototypes were associated with inefficient journey choices. The latter finding suggested that respondents were using unsophisticated planning strategies that were put at a disadvantage by certain route depictions. This has wider implications for suggestions that schematic maps should maintain topographical relationships in order to facilitate appropriate journey choices, with the danger that the inevitable increased complexity of line trajectories for such designs would simultaneously reduce the ability of passengers to identify the most appropriate routes.     

An integrated transportation decision support system for transportation policy decisions: The case of Turkey

From the point of view of the feasibility of providing growth in road capacity parallel to the predicted growth in traffic as well in terms of impact on the environment and health, current trends in transportation are unsustainable. Transport problems are expected to worsen due to the fact that worldwide automobile ownership tripled between 1970 and 2000, and the movement of goods is projected to increase by 50% by 2010. Similar trends can be seen in an even more dramatic way in Turkey. The Turkish transport network has not followed a planned growth strategy, due to political factors. There is no transportation master plan which aims to integrate the transport modes in order to provide a balanced, multimodal system. This study proposes a decision support system that guides transportation policy makers in their future strategic decisions and facilitates analysis of the possible consequences of a specific policy on changing the share of transportation modes for both passenger and freight transportation. For this purpose, based on the wide spectrum of critical issues encountered in the transportation sector, several scenarios have been built and analysed.     

Stakeholders interests,expectations, and strategies regarding the development and implementation of electric vehicles: The case of the Netherlands

In this paper, we study the strategies of the most relevant stakeholders with regard to the development and commercialization of electric vehicles (EVs) and their recharging infrastructure. Building on the perspective of socio-technical transitions, we relate the strategies of stakeholders to their current and future interests, as well as to their expectations with regard to EVs. Our analysis is based on a series of 38 semi-structured interviews with representatives of a variety of stakeholders in the Netherlands.EVs pose both opportunities and threats to various stakeholders. They therefore participate in the development of the emerging EV system, primarily in order to learn about the potential positive and negative impacts of these systems on their interests and, ultimately, to be able to grasp the opportunities and mitigate the threats. In other words, the expectations, interests, and resulting strategies of stakeholders relate to and depend upon the specific configuration of the emerging socio-technical system for electric mobility. We identify six potential conflicts of interest: the division of tasks within a public recharging infrastructure; the allocation of charging spots; the ways in which charging behavior can be influenced; the role of fast-charging, technical standards for charging equipment; and supportive policies for full-electric and plug-in hybrid vehicles.In general, the stakeholders do not seem overly concerned about either short-term returns on investments or long-term negative impacts. In this regard, the early phase of the transition can be understood as a relatively carefree phase. In order to continue the development of the emerging EV system and to keep it on the right track, however, for the foreseeable future, supportive policies will be necessary in order to provide a stable and reliable basis for further market expansion.