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PUBLISHED, Traditionally, game theoretic approaches to measuring transport network reliability have relied on the outcome of a game played between network users seeking to minimize their travel costs and an OD-specific demon that seeks the opposite by damaging links in the network. This problem assumes the presence of only one demon in each OD pair and assumes the capacity reduction to be 50% if the link is selected for damage by one or more OD-specific demons. The game is typically expressed as a path-based formulation, which is computationally intensive since the formulation requires path enumeration. In this paper we relax the assumptions on the OD-specific nature of the demons and the capacity reduction and propose a link-based multiple network demon formulation via the nonlinear complementarity problem approach where each demon is free to select any link to damage. Under this framework, we examine the effects of the proposed model on total expected network cost and reliability measures, as well as demonstrate through specific examples paradoxical phenomena that if one adds a road to a network then all travelers may be worse off in terms of total expected network cost and/or travel time reliability. Overall the results indicate the importance of the assumptions used to total expected network cost and reliability measures, and provide some insights into the problem of ignoring these paradoxical phenomena in reliable and robust network design.

PUBLISHED, Washington D.C., This paper presents the results of a survey which was conducted on an Irish Rail service to ascertain how the value of travel time may change if individuals could partake in another activity while travelling. The survey included a stated preference section which uses a multinomial logit (MNL) model to estimate the benefits individuals would derive from having access to the internet while they travel on public transport. In the survey, respondents were asked would they rather have wi-fi internet access throughout the train or in segregated wi-fi carriage. The results from this study show that multi-tasking while travelling by rail is extremely common, with the majority of respondents participating in two or more activities. The most frequent form of multi-tasking was the use of a mobile phone. This study examined the potential for wi-fi internet access while travelling by public transport. The results found that approximately two thirds of respondents said if wi-fi internet access was available they would use it once or more every week.

PUBLISHED, Washington D.C., Traditionally, game theoretic approaches to measuring transport network reliability have relied on the outcome of a game played between network users seeking to minimize their travel costs and an OD-specific demon that seeks the opposite by damaging links in the network. This problem assumes the presence of only one demon in each OD pair and assumes the capacity reduction to be 50% if the link is selected for damage by one or more OD-specific demons. The game is typically expressed as a path-based formulation, which is computationally intensive since the formulation requires path enumeration. In this paper we relax the assumptions on the OD-specific nature of the demons and the capacity reduction and propose a link-based multiple network demon formulation via the nonlinear complementarity problem approach where each demon is free to select any link to damage. Under this framework, we examine the effects of the proposed model on total expected network cost and reliability measures, as well as demonstrate through specific examples paradoxical phenomena that if one adds a road to a network then all travelers may be worse off in terms of total expected network cost and/or travel time reliability. Overall the results indicate the importance of the assumptions used to total expected network cost and reliability measures, and provide some insights into the problem of ignoring these paradoxical phenomena in reliable and robust network design.

PUBLISHED, Washington D.C., 19p, In the past, transport network design focused on the effect of designs on the transport system alone but not on the land use system, and ignored the land use-transport interaction over time. This may result in obtaining suboptimal designs. Additionally, the impacts of road network improvement policies on the land use system, especially the benefit of landowners cannot be evaluated without considering the interaction. With these considerations, this paper proposes optimization frameworks for road network design considering the land-use transport interaction over time. Unlike existing models, the optimization frameworks can determine the optimal designs automatically without trial-and-error once the objective(s) is/are clearly defined. Moreover, these frameworks allow the evaluation of the impacts of the optimal designs on the related parties including landowners, toll road operators, transit operators, and road users, and help network planners and profit-makers with decision-making by eliminating many alternative designs. A numerical study is set up to examine road network design?s effects on these related parties under three road network improvement schemes: exact cost recovery, build-operatetransfer, and cross-subsidization (using the increase in transit profit to subsidize road improvement projects). The results show that the changes in landowner profits are not the same after implementing any scheme. These unequal changes raise the issue of the landowner equity. If the government guarantees the occurrence of this equity without providing any subsidy, societal benefit can decrease and the road network can become more congested. This implies that the government has to consider tradeoffs between parties? objectives carefully., This research is funded under the Programme for Research in Third-Level Institutions (PRTLI), administered by the Higher Education Authority

PUBLISHED, Washington D.C., Public transport systems are at risk from attacks as they are open, dynamic systems carrying large numbers of people. Although attacks have been carried out on public transport since the 1920?s, the nature of attacks has changed in recent years and the objective of many terrorist attacks is to cause large number of casualties and create major disruptions on the network. The research examines the risk from such an attack on the bus network in Dublin. As part of the research, a framework was developed which can be used to calculate risk using a number of factors which were chosen to take into account the attractiveness of the target, the overall threat and the level of disruption caused. The factors were grouped into static factors (factors that remain largely unchanged) and dynamic factors (factors which change due to further factors such as time). These factors were weighted using the Analytic Hierarchy Process (AHP). Eleven bus routes throughout Dublin were chosen and were analysed under five different scenarios. The research concluded that rush hour and when the buses are operating at high load factors are particularly high risk situations but in off-peak hours the number of possible targets on a route may still mean the risk is relatively high during those times. Limited options are available to mitigate those risks although rerouting during periods of medium to high alert offers some possibility of offsetting the risks of attack.

PUBLISHED, In metropolitan cities an efficient integrated public transportation system is unavoidable in order to restrict unsustainable growth of private and intermediate transport modes. Well designed feeder routes and coordinated schedules to minimize transfer time from main transit to feeder buses play an important role. Past literature reveals that heuristic approach had been popular for design of routes and had been applied successfully in verities of network design problems. Non traditional optimisation technique especially Genetic Algorithms are also found to be very effective in generation of optimised feeder routes and schedules. In this research Genetic Algorithm first develops feeder routes and then a specialized heuristic Algorithm works as repair algorithm in order to satisfy demand of all the nodes. Thus the advantages of both Genetic Algorithm and Specialized Heuristic Algorithm are obtained in this method. The developed feeder route structure is found to be better in terms of load factors in buses, satisfaction of demand and waiting time for feeder buses as compared to existing scenario and earlier approaches adopted by authors far the same study area.

PUBLISHED, This paper presents the results of a study undertaken in Dublin, to ascertain preferences for real-time public transport information. This study examines the need for public transport information across three stages of a public transport trip. The stages examined are as follows; stage one: pre-trip planning from home to work, stage two: at-stop/station information and stage three: pre-trip planning from work to home. At each of these stages the respondents were asked to choose between several methods of receiving information, via the internet, mobile phone, call centre or at stop real-time information displays. The study utilised a stated preference approach to ascertain what type of information is demanded at each stage and the willingness to pay amounts for this information. Specifically, this paper will focus upon the factors that influence the choice of real-time transport information option. Several factors from the literature have been proven to impact upon the utility derived from real-time public transport information. The results from this study are compared against the factors from the literature which have been proven to impact upon utility, to validate the findings of this study. The paper concludes with summary of the main findings of this study and how they contribute to the field of knowledge in this research area.

PUBLISHED, Rural single carriageways in Ireland tend to fall below current design standards and have higher accidents rates (per vehicle kilometre) than roads designed to modern standards. Resources are not available to improve all rural single carriageways; therfore sections need to be identified as priority sections for improvement. Geometric design consistency studies can be used to identify inconsistent sections on highways, which can then be targeted for improvement. No geometric data exists for rural single carriageways in Ireland. A method of estimating geometric data from digital maps was implemented on some 70km of highways. 19 curves and 19 tangents were then selected to represent the overall geometric makeup of the highway. Numerous geometric indices were measured on site. A spot speed survey was conducted at the midpoint of each tangent and curve and operating speed was calculated for each site. The spot speed survey is used to estimate the operating speed on straights (tangents). An operating speed model is used to estimate the operating speed on curves. Using these estimated operating speeds a sample geometric design consistency evaluation is carried out. Elements were classified as good, fair or poor using a design evaluation criterion. An accident database for the N52 was obtained. Accidents that occurred on the N52 and were possibly caused by the road alignment were extracted from the database. 53 accidents at 40 locations were observed. 19 of these accidents occurred in locations that were classified good, 8 accidents occurred in locations classified fair and 13 accidents occurred in locations classified as poor. A relationship exists between geometric design consistency and safety. Of the 40 locations which had accidents over the 8 year period from 1999 ? 2005, 13 of these locations were detected as needing realignment by the geometric design consistency evaluation. A geometric design evaluation can be used to pin point locations on highways where accidents could conceivable be higher. Improvement works and resources can therefore be concentrated on these sections and hence rural single carriageways can be made safer.

PUBLISHED, Data mining concepts are used frequently throughout the transportation research sector. This paper uses the concept of the market basket technique on public transport users as a means of gaining more insight into their transport demands. The paper proposes a method that uses various data attributes of passenger records to infer the same customer in a different week i.e attempts to track the same customer from week to week. The general idea behind the measure is that, if two records are considered similar, ideally every trip in one customer record should have a close counterpart in the other record. The research develops a similarity function and this aims to maximise the percentage of positive ticket identification over a number of weeks. Once similarity has been established, the travel patterns of customers can be useful in helping the operator identify new routes, new timetables and strategic decisions in relation to satisfying public transport customer demands.

PUBLISHED, Many attempts have been made to solve bus route network design problems by splitting it in two stages, one for routing and the other for scheduling. Some researchers have made attempts to solve network design problems using non traditional optimization techniques also, but not much has been done on modeling coordinated operations involving transfers from one mode to another. In this research, feeder routes and frequencies leading to schedule coordination of feeder buses with main transit are developed simultaneously using Genetic Algorithms. The coordinated schedules of feeder buses are determined for the existing given schedules of main transit. Thus the developed feeder routes and schedules are complementary to each other. As a case study the Dun Laoghaire DART (Dublin Area Rapid Transit) (heavy rail suburban service) station of Dublin in Ireland is selected. Finally the outcome of the research is a generated feeder route network for feeder buses and coordinated schedules of feeder buses for the existing schedules of DART at the selected station. The results of the proposed model indicate improved load factors on developed routes and also the overall load factor is also improved considerably as compared to authors? earlier model.

PUBLISHED, Over the past number of years infrastructural development has been a major concern in Ireland. The economic upturn of the country has required significant developments in this area in order to maintain the financial position the country now finds itself in. The Irish Government has acknowledged that the lack of infrastructure, particularly public transport, is creating a serious congestion problem. At an urban level, two lines of a Light Rail Transit (LRT) System have been introduced into Dublin this year. They were funded from the European Union (EU) and government funds. An extension of one of the LRT lines is currently at procurement stage and the paper uses the Tsamboulos method to assess if it is likely to be attractive to private finance. It was found that investors are likely to be very averse to planning risk but are less worried about financial and construction risks., Railway Procurement Agency (RPA)

PUBLISHED, The aim of the EU funded UNITE research project was to provide information about the costs, benefits and revenues of all transport modes including environmental and social costs. The project involved compiling accounts for 18 countries across Europe with each country having its own set of accounts in such a format that comparisons, where possible, could be made. The paper focuses on the latter two sets of costs i.e. environmental and social for Ireland. The account presented here is a pilot account (rather than an ideal account) i.e. the actual, feasible accounts given the available data. The costs are reported and documented at the current level of transport demand for the reference year 1998 but data for 1996 and projections for 2005 are also included where data and historical trends allow. The paper concludes with some comparisons between transport costs in Ireland and some of the other European countries examined in the UNITE project. The accident costs in Ireland (?50/capita) lower than those for Denmark (?120/capita), Netherlands (?80/capita) and about the same as Spain (?50/capita), are considerably less than those in Austria (?160/capita) and larger than those of France (?20/capita) and the UK (?25). Noise costs are ?100/capita and are close to those of France, Spain and the UK. They are higher than those of Netherlands (?20/capita) and Austria (?40/capita)., European Union (EU)

PUBLISHED, This paper presents the design and manufacture of surface acoustic wave (SAW) strain sensors which can be produced in a university environment. These sensors can be interrogated wirelessly and operated without a power supply, which allows for greater measurement flexibility than conventional strain gauge systems. The design of an optimised sensor requires accurate experimental data on a number of process parameters and configurations, which for this project requires the testing of several prototype designs. The large prototyping costs typical of SAW devices can be significantly reduced if the design and manufacturing processes are integrated. This paper outlines such a system, where device function and processing issues are integrated at each stage. The result is a range of sensors which have been "designed for manufacture", optimising both the variety of devices per wafer and the yield, Funded by the Centre for Transport Research and Innovation for People (TRIP) at Trinity College Dublin, which forms part of the HEA?s PRTLI initiative. Device fabrication is carried out with the assistance of the SFI Trinity Nanoscience Laboratory

PUBLISHED, The arguments in defence of poor attention to those with disabilities in terms of offering equal opportunities to transportation options tend to centre on the high cost of provision or improvement in facilities. The paper examines the current quality of service on a variety of modes and mode ancillaries such as stations and stops as determined by individuals with disabilities. This is followed by an examination of the measures required by the disabled to improve the quality of service. The evaluations are done with 4 types of disability groups and although the samples of individuals involved are small, the findings are incisive and clear. The improvement measures discussed fall into two categories; those that are costly and those that are more to do with a little more consideration being given on the part of the transportation operator when locating, for example, timetables at a lower level at bus stops to facilitate wheel chair users or announcing stops as buses approach them. Low cost solutions it would seem, in a lot of cases, could be considered marginal changes to work practices or decision making but the impact they could have on quality of service indicators for the disabled, such as accessibility, would be considerable.

PUBLISHED, In June 2001 Dublin Bus introduced a real time passenger information (RTPI) system on the first of its eleven quality bus corridors (QBC), on the Lucan QBC. The introduction is part of a three-year pilot programme called 'Q-time', which was established to test RTPI on three QBCs before deciding on the roll out of the system across the Dublin Bus network. This system displays, passenger information with regard to the estimated wait time on passenger information displays at bus stops along the Lucan QBC. In this paper the authors examine through observations taken from the Lucan corridor the accuracy of the information displayed at the bus stops. These observations measure the day, time of day, route, stop and arrivals; early, late and on time. From this information it has been possible to measure the exactness of the data displayed at the bus stop and to what degree passengers can have confidence in its accuracy. This analysis is complemented by results of a survey carried out in conjunction with the observations on the Lucan corridor. The purpose of the survey is to ascertain what passengers want displayed on the passenger information display. Should it be solely transport related? Or should it be integrated to provide information on local amenities they may use given that they know the estimated time of arrival? The paper will conclude with recommendations on the current Dublin Bus system with regard to the reliability of the data and what other information passengers wish to see displayed., This research is supported by the Department of Transport under the Transport Research Programme, administered by the Higher Education Authority.