This paper is to compare the difference of heterogeneous effect caused by multiple sources, including unobserved heterogeneity in alternatives, taste variation, and heterogeneous choice sets. We construct several heterogeneous discrete choice models to conduct with various heterogeneities. A stated preference data of intercity travel choice is used as empirical case. The empirical results show that the mixed logit model conducting with taste variation has better explanatory power in single heterogeneity and heterogeneous competing destinations model integrating multiple heterogeneities has the best explanatory power. If we ignore heterogeneity in constructing discrete choice models, the estimation of value of time will be biased. Sensitivity analysis presents that expensive alternatives, like air mode, should adopt cut-price strategy to increase choice share and inexpensive alternatives, like bus and train mode, should improve the level of service in travel time to increase choice share.

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An origin-based solution algorithm, named OBTAIN (origin-based traffic assignment for infrastructure networks), was recently developed for solving the traffic assignment problems (Bar-Gera and Boyce, 2003). This algorithm defines the solution variables in an intermediate way between links and routes, and has been proven to be superior to the link-based Frank-Wolfe method in both computational time for and accurate level of the solution for a large network. To address its usefulness, the OBTAIN algorithm is elaborated in a tutorial manner, especially in its two major steps for updating the restricting subnetworks and origin-based approach proportions, and then applied to a small supply chain network equilibrium problem. The obtained results comply with the sufficient conditions for restricted user equilibrium. Future research includes a real application of large networks and a comparison of the OBTAIN algorithm with the route-based gradient projection (GP) algorithm in terms of computational efficiency.

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In this paper, the impact of road pricing on the transport network reliability is investigated with the use of a newly developed reliability-based user equilibrium (RUE) model. The RUE model can be adopted to overcome the difficulty in predicting the flow pattern in a congested and unreliable road network. In this RUE model, both the travel time and travel time reliability are taken into account for drivers' route choices by introducing a concept of path preference index (PI) to quantify the attractiveness of each alternative path for travel between a particular origin-destination pair. The PI is a weight sum of the path travel time index (TI) and the path travel time reliability index (RI), which represent the travel time and travel time reliability on a particular path respectively. The RUE model can be applied to investigate the effects of road pricing on travel time and reliability in urban road networks, in which drivers would consider both the travel time and its reliability for their route choices. In this paper, the RUE model is extended to maximize the network reliability by road pricing. The results demonstrated the trade-off between the total network travel time and the network travel time reliability. The effects of the toll on the total network travel time and the network travel time reliability are investigated.

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This paper proposes a method for evaluating the effect of transit fare systems on passengers' behaviour using a fore-constructed, capacity-constrained, transit assignment model. The optimum fare setting model is formulated as a mathematical programming with equilibrium constraints (MPEC) problem in which passengers are assumed to choose the minimum cost paths where a user equilibrium condition is achieved. Both total cost and connectivity reliability, which is defined here as the probability of arriving at the destination without failing to board at any station, are adopted as the evaluation index of the problem. The equality of the congestion mitigation effect for each OD pair is considered explicitly utilising the idea of the Gini coefficient, which is the economic indicator. The proposed model is solved using NSGA-II (Non-dominated Sorting GA), which is one method for solving a multi-objective optimisation problem. Finally, a numerical example for a simple network is shown.

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We propose a multimode stochastic dynamic simultaneous route/departure time equilibrium model. The mode-classes typically refer to different vehicle types such as passenger cars, trucks, and buses sharing the same road space. Each vehicle type has its own characteristics, such as free flow speed, vehicle size. We extend single mode deterministic point model to multimode deterministic point model for modeling the asymmetric interactions among various modes. We prove the multimode deterministic point model within each mode-user meets the FIFO discipline, and the speeds of different modes approach consistent during congestion. In order to avoid route enumeration, we present a stochastic dynamic network loading algorithm for simultaneous route and departure time choice maintaining the structure of the DYNASTOCH algorithm of Ran and Boyce (1996), and prove the algorithm does generate the result of the logit flow assignment, and then the diagonalisation algorithm is used to solve multimode stochastic dynamic simultaneous route/departure time equilibrium problem. Finally, the model and algorithm are tested by a numerical example in a simple network.

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Queue spillback is a common phenomenon in congested transportation networks. Nevertheless, traditionally, dynamic traffic assignment (DTA) problems are developed with the point-queue concept in which queue spillback is not captured. Indeed, one recent focus in DTA research is to capture this phenomenon and develop solution methods for the physical-queue DTA formulations. However, the properties of these problems, which have important implications on the theoretical advances and computational issues on transportation planning and operations, are not well recognized and understood. This paper summarizes the properties of physical-queue DTA, compares those with point-queue DTA, and discusses their implications. In particular, the interrelationship among properties including First-In-First-Out, causality, travel-time-link-flow consistency, and queue spillback are emphasized in this paper.

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This study develops a DSO (Dynamic System Optimum) simulation algorithm first, which can reproduce the traffic condition so as to minimize total travel time on condition that time-dependent OD demand is given. Next, the algorithm is verified by applying to a simple network with one OD pair. Recently most of dynamic traffic simulation models reproduce traffic flows dynamically under the principle of DUO (Dynamic User Optimal). On the other hand, DSO solution must provide practical information for the effective traffic control such as ramp metering control and road pricing measure. However, there is no simulation algorithm seeking for the DSO solution Therefore, in this study, DSO simulation algorithm has been developed in accordance with Dynamic Marginal Cost equilibrium principle, which equilibrates DMC of all routes. As a result of the verification, it has been confirmed that the proposed model and algorithm efficiently solved DSO solution.

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Research on the stroller behavior will contribute largely to the creation of high quality walking spaces. People can discover both the positive and negative aspects of their towns through daily strolls. For this study we selected two research areas, one rural and the other urban, in order to investigate and analyze stroll behavior in detail. The types of strolls, the walking distances, and the characteristics of road preferences selected in walking routes were analyzed based on data of the two areas. In addition, by comparing the analyses of the two areas, both the similarities and differences of stroller behavior between rural and urban areas were clarified.

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Recently in Japan, it is crucial to increase inbound tourists. From a view point of tourism marketing, this study aims to analyze relationship between foreign tourists' consumer satisfaction, importance of information gathering and tourists' behavior. First of all, foreign tourists' survey on behaviors and attitudes are conducted in Kamakura, where is a popular sightseeing area in Japan. Secondary, the degrees of tourists' satisfaction are cross-aggregated by Asian and non-Asian and by tourists' Japanese skills. Finally, the LISREL models are estimated in order to explain relationship between tourists' satisfaction and consumer value related to behaviors quantitatively. As a result, it is indicated that average degrees of satisfaction for Asian tourists are relatively lower than those for non-Asian. Especially, degree of satisfaction for signs is low both for Asian and non-Asian. The model estimation results show that to improve service and comprehensibility of signs is necessary to increase foreign tourists' satisfaction.

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One day tour to some facilities is divided into two cases. One is a tour which people plan beforehand. Another is a tour which people don't plan before and decide a next trip in the facility they stay now on (no plan trip). These trips are often on recreation travel and shopping travel. This research proposes a model for One day tour to some facilities with no pre-plan like the latter and applied it for recreation travel. Human behavior has a kind of dispersion. One of them is caused by occasional difference which shows that even same person has different behavior under same condition. The difference is introduced into the model. This study used this model into the results of an investigation which has been carried out about four recreational facilities in Miyazaki city on 1996 August.” As a result, reproducibility of the investigations showed relatively a good agreement.

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This study investigates the recreational cycling and environmental preferences of cyclists in Taiwan. Compared to bicycle tourists using national scenic bikeways and recreational cyclists using local bike lanes, this study explores how the two types of users significantly differ in preferences. By using questionnaire and Ridit analysis, this study investigates two bikeway systems implemented by central and local government separately. The former is a 201.66 km-long bikeway network produced by the National North Coastline Scenic Administration. The latter is a 17 km-long coastal bikeway alone Hsin-Chu city which has been planned by city government. The national scenic bikeway attracts tourists to cycle mainly with the reason of tourist attractions and landscaping. Restated, cycling is not the tourists first priority; while the local bike lane provides opportunity for cycling under the purpose of leisure and exercise.

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This paper attempts to define the relationship between the uninterrupted and interrupted speed at the under-saturated and saturated isolated signalized intersection using the method of characteristics. Due to the nature of interrupted facility of urban road, the effect of detector location is also considered in the model. The model is tested with several sets of simulated traffic data including the under-saturated and saturated conditions, and under the linear and nonlinear density-speed relationship. In some cases, the estimated speed value is not in the feasible region so decreases the estimation accuracy. The introduction of the free flow speed as the upper limit of the estimation leads to more accurate estimate. The results from the proposed method are compared with the results obtained from the trajectory-based method proposed in the earlier work. It is found that the method of characteristics outperforms the trajectory-based method in all cases of traffic data.

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This study aims at investigating the effectiveness of exclusive over/underpasses for small vehicles in alleviating traffic congestion at a saturated intersection in Japan. The design standard of the road for only small vehicles has been established in the road structure ordinance that was revised in 2003. Its effectiveness compared with ordinary over/underpasses is still ambiguous. Therefore, the micro traffic simulation was used to clearly evaluate the impacts of this facility at a single intersection. The evaluation was performed based on changing the reduction of travel time passing through the intersection. It was found that the exclusive over/underpass for small vehicles can alleviate congestion effective ordinary over/underpass, but its construction cost is lower about 30% than the ordinary over/underpass. Furthermore, the heavy vehicles ratio significantly affects its performance. This study suggested that an intersection suitable for an exclusive over/underpass should be selected carefully with respect to heavy vehicle ration in the traffic.

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This study aims to seamlessly integrate transit network with road network in GIS and searching the best transit path between origin and destination (OD). Unlike previous studies, the Transit Route Table and Connectivity Matrix no longer need to be built. The system uses dummy links to combine the road and transit networks to a single network which can represents the real world and traveler behaviors much more effectively so that the development and maintenance of database become easier. Because of the uniformity of its network topology, an ordinary shortest path searching algorithm can be embedded and utilized without any modification. By considering many factors that could affect the travelers' travel and using GIS platform, this system can provide users with friendly interfaces and display visual, feasible and precise results.

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A new geometric design and two types of signal optimization models were proposed to cope with the problem for the left turn traffic from minor road to ramp in TUDI. One model is BMILP that optimizes all signal timings for the proposed design, the other is a combined model that optimizes green intervals by TRANSYT-7F subject to phase sequence and offset resulted from the BMILP. The proposed design and traffic control allows the left-turn traffic to make left-turn and enter the ramp at the upstream intersection. As the result, the left-turn traffic doesn't have to go to the downstream intersection and there are less traffic volumes than those of TUDI at the two intersections. The simulation results showed that the proposed design using the proposed models certainly are superior to TUDI using TRANSYT-7F in reducing delay, where the more traffic (especially the left turn traffic) the greater the effect. Combined model was superior to BMILP for low left turn volume, vice versa for high left turn volume.

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Speed limit is one of the traffic problems in Hokkaido due to unreasonable speed limit for both summer and winter. Based on questionnaires, the opinions from more than half of examinees have shown that speed limit of the roads in Hokkaido is too low and should be different in summer and winter. Then, this study is introduced to adjust speed limit reasonably, depending on road characteristics and road conditions. In this study, Free Flow Speed (FFS) equation is applied to calculate the speed limit in summer. For speed limit in winter, FFS and Stopping Sight Distance (SSD) equations are used. Most of the drivers are satisfied with the results. Moreover, speed limit on a circular curve is adjusted by the minimum radius of circular curve equation. However, these results should be verified in terms of safety and traffic efficiency to obtain the optimal speed limit.

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This paper presents a new automated incident detection framework for both freeways and urban arterial roads. A common modular architecture that includes a special data processing module to handle site specialties is applied to the freeway algorithm (TSC_fr) and the arterial road algorithm (TSC_ar). Bayesian networks are constructed to store general expert traffic knowledge and perform universal incident detection. The TSC_fr algorithm is evaluated using a large number of field incident data sets, and the TSC_ar algorithm is tested using simulation data. The testing results are very encouraging. It is found that both detection rate (DR) and false alarm rate (FAR) are not sensitive to incident decision thresholds. When the decision threshold is above the certain level, both DR and FAR reaches a very stable region. This is the unique feature of the TSC algorithms. The results also demonstrate algorithm transferability is achievable under the new incident detection framework.

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This paper addresses a new discrete equilibrium network design problem (NDP), which is on the selection of pedestrianisation location (i.e. the optimal set of pedestrian-only streets) in a multi-modal transport system with both motorized and non-motorized modes. Given a network of candidate pedestrian-only streets, the design problem is to determine the optimal set of pedestrian-only streets with considering flow equilibrium and modal equity constraints. An equivalent variational inequality (VI) problem is formulated to represent the flow equilibrium constraint. The modal equity constraints are introduced to balance the benefits and/or disbenefits to users of various transport modes, under a pedestrianisation scheme. A bi-level model is proposed to determine the optimal pedestrianisation locations and a heuristic solution algorithm is presented for solving the NDP. A case study based on the central business district of Hong Kong, “Central”, is employed to illustrate the applications of the proposed model and solution algorithm.

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This paper focuses on traffic management in the Philippine City of Vigan. Current traffic conditions are characterized and the Vigan Master Plan's transportation and traffic components are discussed thoroughly. Schemes consistent with the preservation of the city's heritage were examined, and suitable programs were recommended for implementation. The public transportation system is assessed in the light of environmental concerns pertaining to emissions and noise. The role of institutions like the local government and the academe (i.e., University of Northern Philippines) is also discussed especially in the formulation and implementation of traffic management schemes. Such is required to come up with effective traffic programs that would ensure sustainability of growth for Vigan without sacrificing its legacy as a World Heritage Site.

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It is a common practice that VMS (Variable Message Sign) is implemented on the network with alternative routes to achieve optimal traffic allocation among the alternative routes. But VMS has its own limitation. That is, desirable traffic allocation among alternative routes cannot be automatically achieved by the VMS information itself. Rather it is generally known that VMS information generally causes overreaction and concentration problem. Considered is a simple hypothetical network with two alternative routes, one bypass and the other with a physical bottleneck. The concentration problem is illustrated with this sample network. And strategic VMS control is proposed to compensate for the discrepancy between the system optimal and the predicted traffic allocations. To make this control concept work, a new concept and the estimation procedure for the dynamic capacity are provided especially for congested flow condition. Finally, functional requirements for VMS control with overreaction and concentration problem are summarized, which remains for further research.

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This paper develops an iterative genetic fuzzy logic controller (GFLC) model to adaptively control the transit-preemption signal (TPS) along an arterial with consideration of the traffic flows from all approaches. Two transit-preemption strategies, green extension and red truncation, are incorporated with simultaneous, progressive, and alternative coordinated signal systems. Compared with the signal timing without TPS, the case study shows that the GFLC conditional TPS model can curtail the total person-delay by as high as 18.10% while the unconditional TPS model can only reduce 14.47% at most. This study also finds that the GFLC conditional TPS model performs better in light traffic than in heavy traffic.

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A real-time adaptive signal control system, named COSMOS, generated signal control parameters automatically using collected information from loop detectors. Therefore, the reliability of loop detector information can affect the operational effectiveness of the signal control system. In this paper, a set of practical loop detector installation guidelines was developed through extensive field experiments. Results indicated that a laying depth of 12 cm provided good performance regardless of detector types tested. In addition, a laying depth less than 9 cm should not be selected in practice. The limit lengths of feeder cable were determined as 1,000 m for octagon loop detector and 900 m for circle loop detector, respectively. It was also recommended that the number of soldering should be less than 6 times when the feeder cable length was below 600 m, and 4 times when the length was in a range between 600 m and 1,000 m.

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This paper introduces a distributed architecture of the intelligent control integrated system for area-wide incident response, information guidance based on signal control. The paper applies Multi-Agent technique to the system and introduces the relative cooperation and negotiation theories based on game theory, by which the system can realize real-time active intelligent control, especially to actively resolve the congestions happened or will happen at the intersection. Therefore, the coordination problem among several intersections can be handled, which is one of the most important problems of the area control system. In order to realize the integrated control system, the paper also presents the incident and congestion forecast algorithms. Finally, as one intersection signal Agent, it can realize the isolated intersection signal control strategy independently by means of fuzzy logic, which is also considering the bus-priority.

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This paper mainly focuses on the research of the classification method of the mixed traffic flow in the intersection. It falls into three main parts, the research on the intersection mixed traffic flow characteristics, the classification with the method of fuzzy clustering, and the application of the classification in the actuated signal control system in order to choose optimal control strategy. The paper presents a new promising method to classify the mixed traffic flow in the intersection, which is practical and of great necessity. It adheres to the Chinese situation greatly, and could be implied in actual operation. We have took tests in two intersections of it in related research in our instituted. The results are satisfying. More tests will be carried on in the following years to improve this new conception to be more completed.

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Traffic congestions in local cities are caused by concentration of car commuters into specific local points in time and space. Staggered working hours (SWH) that promote temporal dispersion of commuting traffic seem effective in easing the congestions in morning rush hours. The local cities that have often applied packaged TDM measures which jointly combine SWH with another effects. It is important to evaluate the effects of introduction of TDM in advance, however there is relatively less method to forecast and evaluate the packaged TDM measures.
This paper aims to propose a measure that investigates feasibility of introduction of TDM, and to develop a convenient method to evaluate introduction of packaged TDM measures by considering synergy/counterbalance effects. As an empirical study, the effects of the measures, combining SHW with park and ride are evaluated in two typical local cities.

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The paper is written based on research on ‘Dynamic Origin-Destination Matrices From Real-Time Traffic Count Information’. The latest development in automatic traffic count data collection enables us to obtain the traffic count information in a real time or shorttime- interval basis. For example, ATCS (Area Traffic Control System) already installed in several large cities in Indonesia, such as: DKI-Jakarta (since 1994), Bandung (since 1997), and Surabaya (since 1998) provided us the real-time or short-time-interval traffic count information for all signalised intersections. This traffic data is updated periodically in a shorttime- interval basis (e.g. 5, 15, or 30 minutes time interval). This information is provided at the Traffic Control Centre (TCC) of ATCS project and can be directly and easily accessed at a very low cost through internet. This data is the main input for the short-time-interval Origin- Destination (OD) matrix estimation.
Before this type of traffic data is used in the OD matrix estimation process; firstly, these data have to be processed in the Data Processing Interface (DPI). Having it processed; the traffic data will then be ready for estimating the short-time-interval OD matrices. The output of short-time-interval OD matrices together with several practical applications will be the main input for the Real-Time Integrated Traffic Information System (RITIS). This information will be stored in a Website designed specifically and informatively for the purposes of user needs (numerical and graphical).
One of the most important information is the best routes from each origin zone to each destination zone which have already considered the effect of congestion. This information will be the main data for the development of the Route Guidance System (RGS) so that each driver can choose his best route through the road network. The best route information will be changed in a short-time-interval basis depending on the traffic condition. This short-time-interval traffic system information will become the public-domain information which can be directly and freely accessed through internet by the users (e.g. Planning Authorities, Traffic Authorities, Department of Public Works, Consultants, Police, drivers, radio stations, and TV stations, other related agencies, etc). Moreover, this approach can also be extended to provide the short-time-interval environmental information.

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This paper focuses on the development of a dynamic multi-class assignment for evaluation and application of the dynamic route guidance strategy. Travelers are classified into three groups according to information contents which they received before departing or on trip. The first group have no traffic information, so they travel along with fixed route. The second group has real-time shortest path information from travel agency and takes the route. The last group has car navigation system or individual methods such as cell phone, PDA-two way communication for traffic information on trip. So they follow the control of DFS (decentralized feedback strategy) where the control system is operated locally. In order to consider these three groups in a model we propose a multi-class dynamic assignment model. With the proposed model some traffic information strategies are tested and interpreted in terms of ITS (Intelligent transport systems).

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Generally speaking, drivers' route choice is a fuzzy problem. However, if drivers' habitual domain becomes stable and without significant stimuli, route choice becomes a routine problem. Route choice can become fuzzy again if drivers perceive information stimuli. Intuitively, traffic information should help drivers to reach destination in an efficient way, but the abundant and complex information could overwhelm the drivers. In this work, a different and novel approach to complement the driver route choice decision models is exploited. The concept of habitual domains and competence sets proposed by Yu in 1980 is applied to the route choice problem. The effect of traffic information on route choice is isolated to analysis the behavior of route choice decision. Performance indexes of route choice decision are developed to help the drivers or the traffic information providers in expanding their competence sets to fully address the needs of route choice decision.

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In this paper, the methodology for selecting the most preferred solution from a set of non-dominated solutions developed by a multi-objective automatic vehicle identification (AVI) reader location model is proposed. Several criteria, which have not been considered in the multi-objective mathematical formulation, are incorporated in the selection method to differentiate the non-dominated solutions. Not only does the method assist the decision makers in dealing with this unmanageable set of solutions, it is also capable of taking into account the practicality issues of solution, which cannot easily be addressed in the mathematical model. The proposed method is applied to select the most preferred configuration of an AVI system for the simplified Irvine network in Orange County, California as a case study.

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Data fusion techniques are applied to traveler information services and used to build an accident duration estimation function. The accident duration is estimated at the initial occasion of an accident. The data fusion procedure clusters the values of each factor into a small number of intervals and effectively smoothes the data noise to the model. In most experiments, the mean absolute percentage errors of the estimated outputs are under 25%, indicating an acceptable forecasting effect. Through the factor sensitivity analysis, time of day, number of vehicles & vehicle type involved in accidents, and geometry have high significance in conducting the accident duration models. The results confirm that the data fusion techniques are practical and reliable for developing traveler information systems. This study is granted by National Science Council, Taiwan, under the project number NSC93-2218-E-006-094. It shows very promising practical applicability of the proposed models in the Intelligent Transportation Systems context.

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For the last two years, Korean Highway Cooperation (KHC) has developed a location-based Dynamic Route Guidance System (DRGS). The targeted end users of the system are mobile-phone users in Korea. The service is scheduled to be commercialized in 2005. Spatially the system will cover all of the expressways which is about 2,800 km and some of the National highways which is about 500 km. The focus of this paper is about the use of historical travel time data for travel time forecasting which is embedded in the location-based DRGS development project of KHC. This study firstly shows that for certain future time periods (e.g. 60 minutes later from now on) travel time forecasting using only the historical profile without real-time profile is better than the one using real-time profile or both. Then the methods of constructing historical profile including removing outliers, identifying optimal amount of historical data for the historical profile, and determining optimal update frequency of the historical profile are discussed. Finally the proposed methods are demonstrated with the travel time information collected from Kyongbu expressway in Korea.

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On-line traffic information is one of the crucial components that affect traveler's decisions. Particularly, in the event of traffic incidents, motorists might avoid traffic congestion and/or delays, through consulting means of highway advisory devices (e.g., VMS or HAR) or personal digital agents, in assessing relevant traffic incident and guidance information. Therefore, the issues of route diversion and value of traffic information in route guidance control scheme become significant. In the present research, a systematic framework based on traffic assignment models is proposed to analyze the value of traffic information in implementing route diversion strategies for on-line traffic management purposes, especially under the impacts of traffic incidents. To demonstrate the feasibility of the proposed framework, numerical analysis was conducted in light of simulation experiments. The test results indicated the capability of the proposed framework in evaluating the value of traffic information. More significantly, one can foresee the possible outcomes and potentials of traffic information, and evaluate the cost-effectiveness of information provision strategies.

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The aim of this study is to discuss the feasibility of a system to collect traffic information using probe vehicles in a developing city in terms of cost efficiency. Firstly, the field test that applied five taxies as probe vehicles in Bangkok was conducted to identify their running performance and characteristics. Secondly, based on the result of field test, a micro simulation model was developed to verify the minimum number of probe vehicles that can ensure sufficient data collecting information from which reliable average travel time can be calculated. Finally, to estimate the cost of system, the amount of transmitted data from probe vehicles was calculated when probe vehicles collected traffic information dynamically applying the minimum number of probe vehicles. As a result, it was found that average travel time of all vehicles can be estimated in every 15 minutes at half of all road sections in Bangkok, if all taxis can be used as probe vehicles.

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Here, we examine the effects of traffic information provision on driver behaviour. While many previous studies have evaluated the effect of traffic information provision using hypothetical traffic conditions, here we evaluate measures using actual observed link traffic volume. A dynamic path-flow estimation model was used to obtain time-dependent path traffic volumes, and the estimates were contrasted with provided real travel time information. The results show that travel time information provision has a big effect on route-choice behaviour. Furthermore, parameters of a logit model were estimated, and the validity of the model was investigated. The effect of travel time information on driver behaviour was found to be statistically significant.

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The benefits of using ETC instead of manual toll payment are clear. It has been observed in Philippine expressways that the average service time per vehicle with E-pass is 1.5 seconds compared to 15 seconds for manual collection. This translates to reduced traffic congestion at toll plazas, lower fuel consumption, less air pollution, and therefore less economic losses. However, the current number of E-pass subscribers is still small compared to the number of toll road users. Possible reasons are the high initial cost of subscription, infrequent use of tollways by some users, lack of information, etc. To ascertain these reasons and to understand the factors that can increase E-pass subscription, it is important to know the perception of people about the ETC. This study aims to gather people's assessment of ETC; identify factors that would make non-ETC users shift to ETC; relate socio-economic - characteristics with ETC acceptability; and develop a framework estimating the environmental benefits of ETC.

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This study develops a travel time estimation process by integrating a missing data treatment and data-fusion-based approaches. In missing data treatment, this study develops a grey time-series model and a grey-theory-based pseudo-nearest-neighbor method to recover, respectively, temporal and spatial missing values in traffic detector data sets. Both spatial and temporal patterns of traffic data are also considered in travel time data fusion. In travel time data fusion, this study presents a speed-based link travel time extrapolation model for analytical travel time estimation and further develops a recurrent neural network (RNN) integrated with grey models for real-time travel time estimation. In the case study, field data from the national freeway no. 1 in Taiwan is used as a case study for testing the proposed models. Study results showed that the grey-theory-based missing data treatment models were accurate for recovering missing values. The grey-based RNN models were capable of accurately predicting travel times. Consequently, the results of this study indicated that the proposed missing data treatment and data fusion approaches can ensure the accuracy of travel time estimation with incomplete data sets, and are therefore suited to implementation for ATIS.

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Many map matching algorithms have been developed to match GPS points to a digital map in previous studies. But the previous studies assume short polling time intervals(about 1 second) of the GPS data. And the map matching algorithms of such studies are not appropriate for the GPS data with relatively long polling time intervals(about 2∼5 minutes). In this paper, we will review the previous map matching algorithms and discuss the map matching algorithms which can be used under circumstances of relatively long polling time intervals.

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Origin-Destination (O/D) is important information in route choices and trip assignments. In this study, methodology of estimating O/D based on cellular base station information is proposed. GPS coordinates and cellular base station coordinates have acquired on taxies in Cheongju. Three weeks' data were collected and used. Scatter diagram and sample correlation coefficients show that there are few significant differences of O/D pattern among weeks. However, there is a difference in O/D pattern between weekday and weekend. Besides, there is a difference between morning peak and evening peak. Two methodologies are proposed to convert cellular base station-based O/D into an administrative district-based O/D - using the distribution pattern ratio of GPS coordinates and using the coverage area ratio of the base stations. The statistical analyses through scatter diagram, MAPE and RMSE show that there is few significant difference of pattern between the estimated BS-based O/D and GPS-based O/D.

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Computer vision system is one of important research topics in ITS(Intelligent Transport Systems). Moreover, Neural Networks have been increasingly and successfully applied to many problems for ITS. Even though there are currently many different types of neural network models, Backpropagation is the most popular neural network model. It is however known that the Support Vector Machines (SVMs) based on the statistical learning theory is currently another efficient approach for pattern recognition problem since their remarkable performance in terms of prediction accuracy. In this research, two different models, Backpropagation and SVMs have been studied to compare their performance in predictive accuracy through the experiment with real world image data of traffic scenes. Experimental results show that SVMs can provide higher performance in terms of prediction performance than any other models.

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In traditional traffic information estimation method, the difference in positions is used to estimate traffic information. However, variation or flutter of positioning caused by imprecise mobile phone location accuracy may lead to the unstable measurement. Take the latest mobile phone location technology into consideration, this paper introduces a new segment based traffic estimation method. It is proved by simulation approach that segment based method performs well when location accuracy is within the length of a segment. Simulation results also demonstrate that segment based method is better than traditional method under all kinds of traffic condition except for the high location error and over saturation condition. Through simulation analysis, we conclude that enough sample size, i.e. larger vehicle generation rate, longer data collection interval, shorter location update interval, and larger mobile penetration rate are crucial factors to generating accurate traffic information.

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The objective of this research is to develop techniques for travel speed estimation of main roads using GPS and Mobile (mobile phone) data collected from probe vehicles. To this end, a methodology for travel speed estimation need to be developed first and the reliability of the estimated travel speed in terms of accuracy need to be evaluated.
The coordinate of a mobile location means the location of the base station and not that of the actual probe vehicle. Therefore, erroneous coordinates of the mobile location may result in inaccuracies in the estimation of travel speed based on LBS.
The factors determining the reliability of travel speed using LBS are the number of base station, the distance between nearby base stations, the coverage of base station, and the data collection time interval. To estimate a stable travel speed, the base station network should be dense, that is, the base stations should be close together and its coverage should be dense. It needs to collect data for the estimation speed through detailed data collection time and at reasonably long data update time interval.

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Incidents on the freeway disrupt traffic flow and the cost of delay caused by the incidents is significant. To reduce the impact of an incident a traffic management center needs to quickly detect and remove it from the freeway. In this vein quick and efficient automatic incident detection has been the main goal of the transportation research for many years. Also many algorithms based on loop detector data have been developed and tested for automatic incident detection. However, many of them have a limited success in their overall performance in terms of detection rate, false alarm rate, and the mean time to detect an incident. The objective of this paper is to propose a robust and reliable method for detecting an incident on the freeway using a fuzzy based neural network model, Fuzzy ARTMAP which is a supervised, self-organizing system claimed to be more powerful than many expert systems, genetic algorithms, or other neural network models like Backpropagation. The experiments have been done with simulated data, and the results show that Fuzzy ARTMAP has the potential for the application of automatic incident detection in the real world, where a large number of incident data is not always available for training.

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When we measure travel speeds of road sections, wider range of travel speed would be obtained. Driving in slow-speed sometime increases the stress of other drivers who intend to travel in higher speed. This might lead to hazardous behavior on the part of impatient drivers, such as reckless passing. This study aims to clarify in what situation drivers develop stress and what psychological and behavioral characteristics are manifested under these conditions. A basic survey was conducted to gain an understanding of the driving behavior of drivers under stress and their focus of attention as well as changes in their stressed condition. A full-scale survey was then made to gain insight into the extent of effect the provision of information has on driver stress. From the result of these surveys, it is found that the reduction in the stress differs according to the kind of information supplied from slow-moving vehicles ahead.

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Variable message signs (VMS) are used to provide dynamic information and are currently used to show different speed limits under different conditions. As speed is an important contributor to road accidents, present study focuses on how well traffic advisory information will help drivers to divert from potentially dangerous conditions. Driving simulator experiment in a laboratory setting on 8.5km long simulated Oyamazaki section made easy to examine the effect of VMS and geometry on mean speed and speed deviations. To create a model of mean speed and speed deviation, a system of two equations will be set up where mean speed and speed deviation appear endogenously. To estimate these two structural equations simultaneously best to use three stage least squares (3SLS) method. Analytical results provide discussion on speeds adopted by each subject and detailed interpretation of 3SLS estimations of mean speed and speed deviation with respect to VMS and geometry.

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Treatment of small intersections is one of the most important factors in considering the area wide safety improvement. In order to evaluate and select an appropriate method from among the various devices and systems available, the impact of any introduced method must be appraised using short time observation without any long-term accident records. The aim of this study is to develop an assessment method for the risk of intersection accidents at small intersections by using traffic behavior observation. Vehicles' speed and acceleration during approach to intersections are analyzed by employing a digital video system. A new assessment index is proposed that expresses the ratio of dangerous approaching vehicles, which would not be able to stop and avoid a crossing collision if a vehicle should approaches from the right of way side. In conclusion, this index showed a good correlation with the number of accidents that occurred at the intersection. The author also appraised effect of an automatic warning sign system by comparing vehicle behavior.

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We proposed two types of signal optimization models formulated in BMILP to integrate pedestrian crossings into traffic movements under under-saturated traffic flow. The model simultaneously optimizes traffic and pedestrian movements to minimize weighted queues of primary queues during red interval and secondary queues during queue clearance time. A set of linear objective function and constraints set up to ensure the conditions with respect to pedestrian and traffic maneuvers. Optimization results from numerical examples illustrated that pedestrian green intervals using proposed models are greater than those using TRANSYT-7F, but opposite in the ratios of pedestrian green intervals to the cycle length for single pedestrian. In double pedestrian crossings, the differences among the ratios for the proposed models are smaller than those for TRANSYT-7F. The simulation results show that proposed models are superior to TRANSYT-7F in reducing delay, where the longer the pedestrian green interval the greater the effect.

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This paper proposes an algorithm to identify multiple alternative routes with the multi-label vine-building shortest path algorithm while incorporating turning penalties and prohibitions. The used shortest path algorithm keeps several node labels through the vine search and improves the backward tracing method by excluding all illogical movements at intersections. It also adopts the concept of the rational upper boundary in evaluating the realism of alterative routes considered. The multiple node labels used in the algorithm can foster more effectiveness of the routing advisories and information through analyzing alternative route characteristics in various ways. A simple network is used to analyze the applicability of the proposed algorithm to generate realistic route choice sets. The results show that the proposed algorithm is capable of incorporating various driver behavior classes. The reasonable multiple paths could be effectively used especially in application of ATIS operation which requires sophisticated alternative paths for each traveler.

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Real-time origin-destination (O-D) flows are important input data for most freeway management systems, and very difficult to obtain. This research puts forward two categories of parameter optimization models for estimating dynamic O-D flows in freeway corridors. The proposed models make full use of information from ramp traffic counts and mainline flow measurements, which are provided by surveillance systems. The models also take into account time-varying route travel time, which is estimated by using a recursive method reported in this paper, and realistically formulate the nonlinear dynamic interrelations between O-D fractions and traffic flow measurements. A genetic algorithm is presented to improve the accuracy and operational efficiency necessary for practical applications. The results of simulation experiments indicate that the proposed methods are rather accurate, robust and efficient, and offer the potential for real-time applications.

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The main purpose of this study is to provide a basis for evaluating the public transport policies such as public transport priority systems (PTPS) by developing microscopic traffic simulation model. In this study, two types of public transport policies have been considered for evaluation. They are: bus lanes and PTPS at traffic signal. Fuzzy logic reasoning has been incorporated in route choice analysis while choosing the route based on the level of satisfaction of the available routes. To demonstrate the validity and applicability of the developed microscopic simulation model, a part of the Gifu city network (60 nodes and 204 links) has been considered and estimated traffic condition without and with policy options. It can be concluded from the output of the present study that developed microscopic traffic simulation model predicts vehicle movements with fair amount of accuracy and can be used to evaluate various public transport policies particularly PTPS.

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We considered the driving simulator that was suitable for road surface evaluation and added new functions to a conventional driving simulator. Kitami Institute of Technology driving simulator (KITDS) has two distinct functions. As the 1st function, it makes possible to generate vehicle motions traveled over any pavement surfaces using measured profile data. As the 2nd function, it enables to reproduce the various vehicular motions using measured 6 degrees of freedom (d. o. f) vehicle motion data. The driving simulator offers advantages in high-security, high-repeatability and economical efficiency. In this study, In order to verify the reproducibility of a vehicle motion by the motion platform of KITDS, we reproduced the theoretical signal and an actual vehicle motion. Additionally, we compared input vibration with the reproduced vibration. In conclusion, the vertical acceleration that is an index related to the ride comfort showed high reproducibility in the frequency band of 0.4 to 10Hz.

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