The flood caused by typhoon Morakot in 2009 resulted in mass fatalities in Taiwan, prompting demands for improving coping capacities in cases of extreme climate events. The capacity improvement must involve improving awareness as well as determining and relieving socioeconomic and environmental vulnerabilities. Along with resource allocation and pre-evacuation, transportation systems play a crucial role during the disaster response and recovery. In fact, highway bridges significantly impact the accessibility of transportation networks. However, previous literature has focused on the physical vulnerability of bridges from the engineering or disaster-loss assessment perspective. This study thus examines the disaster risk of bridge failure from the vulnerability perspective. Eleven vulnerable factors are generated by impact chain and evaluated via geographic information system. The results reveal that accessibility and redundancy significantly affect vulnerability and risk. The risk maps help decision-makers understand the vulnerability and adopt appropriate strategies for reducing disaster risk.
In the wake of the devastating 2004 tsunami, a number of researches shifted their focus to disaster prevention, management and alleviation strategies. Most studies developed their plans through reviewing and modeling the characteristics of the great tidal wave. This study from Phuket Island, nonetheless, investigated the other side of the subject from the evacuees’ perspective. Route choice decision and its governing factors were determined. Their relationship to socioeconomic characteristics of local residents and foreign tourists were analyzed and quantified using a three-way contingency table technique. The study found an astonishing fact of an insignificant role of evacuation signage in guiding the evacuation route, as compared to individual instinct and the crowd reaction. The conclusion of the study would be the first step to help understand the crowd behavior and to help establish an effective evacuation measures under this specific emergency situation.
This paper proposes an integrated scenario tree model that incorporates recurrent congestions and sporadic disasters into a stochastic degradable road network design problem (SDNDP). The traffic pattern of the stochastic degradable network (SDN) under the recurrent congestion condition is evaluated by probit-based stochastic user equilibrium (called SDN-SUE), whereas the system optimum is used to assess the traffic pattern of the SDN under the sporadic disaster (called SDN-SO). The proposed model determines optimal link capacity expansions that minimize the sum of the total network travel time costs of all recurrent congestion conditions plus the total expansion cost subject to the desired total network travel time constraints for evacuation purposes and the SDN-SUE and SDN-SO conditions. A solution algorithm is also developed for solving the SDNDP. Numerical examples are given to demonstrate the potential pitfall in considering the network improvement policies separately and to show the benefit from the integrated model.
This study aims to explore the extent of the expectations of the users of the park-and-ride facilities and the level of the actual performance of the facilities in the main stations of the facility on the Kuala Lumpur conurbation. In understanding the gaps, the areas of concern were the facilities, the trip characteristics of the users, the attitude of the users and also the marketing and promotional strategies of the operator and the related bodies. Towards fulfilling this, a gap analysis was undertaken on the output of the questionnaire survey of 200 users of the park and ride facilities. The analysis indicates the relatively wide gap in terms of the attitude and the promotions done. The output of this study thus provides a good feedback to the related parties towards enhancing the promotions and the services at large.
The aim of this paper is to investigate intra-week fluctuations and trends in the dry bulk freight market and to estimate predictive model of freight index for short run pricing strategies in shipping business. In regular terms, five trading days exist in a week and investors may tend to move over the trends of the beginning of a week. Therefore, a spillover effect exists between Monday and Friday pricing tendencies of freight market. This paper investigates existence of intra-week spillover effect and estimates its structural model by using classical linear regression method. Foremost results indicate strong relationship between both ends of the week.
Public Private Partnerships (PPPs) around the world have become increasingly popular as an alternative way to finance infrastructure projects. Some of these projects also have growth opportunities and may be in a better position to be developed as a multi-staged project. Economic valuation methods such as discounted cash flow (DCF) ignore strategic values such as expansion options embedded in these projects, which result in undervalued project. Real options, commonly used with decision trees analysis (DTA), were introduced to address this problem of the DCF. However, The DTA assumes the time to make a decision is predetermined. This assumption is invalid when the decisions can be made any time within a project life. This paper presents a flexible point decision tree analysis (FP-DTA) and the Branching and Folding Back (BFB) method, upon which FP-DTA, real options, and Monte Carlo simulation are based. This approach helps facilitate project economic evaluation under uncertainty.
The Korean government prepared and published sustainable transport indicators in April 2010, and with these indicators, evaluated the transportation sustainability in each of 84 Korean cities. The purpose of this study is to measure and evaluate the transportation sustainability in OECD countries with the same indicators as were used in Korea, allowing the comparison between the present position of Korean transportation sustainability and economic scale with other nations. According to the evaluation based on 2007 data, European countries such as Norway and Sweden received a favorable evaluation, while Korea was in grade 4; Canada, the USA, Australia, and New Zealand scored even lower. There is not enough data to explain the relationship between economic scale and transportation sustainability, because the results could be different if other economic indicators are applied. This study can be meaningful in examining the present position of Korea relative to other nations helping to establish and enforce future sustainable transportation policy.
Socio-economic development generates new travel demand that strains the capacity of existing road systems and produces negative externalities posing resource and technical challenges to local governments in the Philippines. This research explored the viability of introducing Traffic Impact Fee (TIF) at local levels as a policy response. The TIF requires new developments to pay a proportionate cost of improving road capacity. An improvement-driven TIF model, using a limited area approach, was applied on a residential development project in Cabanatuan City to understand the opportunities and constraints arising from TIF implementation. The research concludes that there is potential for TIF adoption.
This paper examines the effects of toll free policy for expressways which is to be introduced in Japan. A model that is developed by combining a general equilibrium model of a multi-city economy and deterministic user equilibrium traffic assignment model is applied for examining the effects of the toll free policy. In the model, cities are linked by a road network including toll expressways. It is shown that the toll free policy applied to all of the expressways in Hokkaido, Japan brings about the social welfare of 31.2 [billion JPY/year], and that applied to some part of expressways where traffic congestion rarely occurs brings about the social welfare of 41.2 [billion JPY/year]. The social welfares presented in this study are calculated from the utility levels of households in the economy.
This paper, as a part of a series of researches focusing on relationships between organizational structures of urban public transport and entire urban transport systems, focuses on how to describe and typify the organizational structure. With a literature review taken into consideration, a diagram is developed to describe organizational structures. Then, using this, structures of four cities, namely London, Vienna, Tokyo, and Soul, are described. Following this, three typologies are derived from the structures in the four cities. At the end, brief discussions related to the main focus of the research - relationships between the organizational structure and transport systems - are made.
This paper aims to find a suitable metropolitan transportation planning (MTP) approach and metropolitan transport organization (MTO) for Bandung Metropolitan Area (BMA). Analytical Hierarchical Process (AHP) was used by interviewing each cities’ representative, non-government organization and professionals. Three approaches for MTP process were investigated: bottom-up, top-down and combined, and three types of metropolitan transport authority organization were examined: adhoc organization with no power, powerful organization and a hybrid type. Criteria for MTP approaches were form of participation, government’s policies, availability of technical skills, form of socialization media, effective coordination and cooperation, effective structure organization and likely political support. Criteria for MTO were government policy, access to fund, cooperation and coordination, professionals’ availability and geographical size. The results showed that both top-down and bottom-up approaches have to be combined, and it was found that a hybrid type of authority organization is more suitable for BMA transport planning governance.
Due to the rapid development of road passenger transport, the business of Road-Passenger-Transport-Based Express has been developed. However, the low office density and bad security limits its further development. This study implements a survey and builds a model to analyze the mode choice behaviors of shippers. Some suggestions on expanding their market share are offered based on the choice behaviors analyses. In the study, firstly the express modes are divided into pure-air transport and non-air one, and the latter is further divided into EMS, RPTB express, professional express and van express. Secondly, sensitivities of the access distance, client occupation and service level on the market are analyzed. At last, based on the findings, a business method, in which the road passenger transport operator and the urban transit company does the works of collecting and distributing expresses, is suggested.
The objectives of the paper are to investigate process of voluntary change in travel behavior and to evaluate the impacts of psychological factors by trip purpose. For the analysis, a total of 1,000 samples, randomly selected from three cities in the Seoul Metropolitan area in Korea were used. The survey questionnaire contained 10 sections (including four sections for psychological factors) and 19 questions. We also constructed three psychological process models by trip purpose (Commuting, Shopping, and Leisure trip) based on a structure equation model using AMOS 16 software. The estimation results showed there are different variables that can affect the process of voluntary car use reduction and the coefficient of trip purpose. Furthermore, this paper suggests an effective MM policy guideline that considers the features of trip purpose based on the estimated models.
Although high-speed railway (primarily Shinkansen) networks have shown improvement in recent years, such services still lag in some areas. As for air travel, following deregulation, some carriers abandoned domestic air routes that were unprofitable and reduced services to others. Therefore, intercity travel times have actually increased in some areas of Japan. However, intercity mobility is different for each pair of cities, and improvements to transportation infrastructure and services are often the subject of intense debate when needs to rectify regional disparities are discussed. The purpose of this study is to clarify disparities of Japanese intercity mobility from 1971 to 2009 using the Malmquist index. Following which, the causes of increasing or decreasing disparities in intercity mobility are analyzed. The results of this study indicate that intercity mobility disparities showed decreasing trends prior to 1991. However, since 1994, such disparities have increased slightly.
This study aims at explaining the fundamental nature of vehicle ownership in a mid-sized city of Thailand. The data used in this study is extracted from a household vehicle ownership survey recently conducted in Khon Kaen City, Thailand. A validity assessment on the data is also undertaken and briefly presented. Models developed in the study suggest that the nature of car ownership in the study area appears to be frankly understandable and consistent with previous studies. On the other hand, behaviour of motorcycle ownership is rather more complicated than that for car, and somewhat deviations from the suggestions given by previous studies. Findings of this study have also proved that the study area is fairly unique from million-population cities where previous studies were undertaken. Eventually, several concerns and issues found in this study are given as a direction for future studies on vehicle ownership in mid-sized cities of Thailand.
In tourism demand analysis, the random utility model has been used to estimate data including tourists’ site selection processes. Recently, the Kuhn-Tucker model (KT), which is more consistent in relation to the utility maximization problem, has been developed. In this study, the attributes of demand analysis using KT are examined through comparison with the repeated discrete choice model. The travel data for eight sites in Nara Prefecture in Japan were used. As a result, the demands calculated using KT are (1) consistent with the observed data and (2) larger than those calculated by the repeated discrete choice model. Finally, the magnitude of the substitution effects is examined. It is concluded that Nara area has the largest substitution effect among all sites.
This paper formulates a departure time choice based on a time allocation model and analyzes it with the empirical data. Stated choice data of urban rail commuters are used for empirical analysis. The model assumes the continuous time choice in which an individual maximizes his/her utility under the constraints of time and monetary budgets. As our model explicitly incorporates the utilities stemming from sleeping hours and in-home or out-of-home leisure, the individual’s preference of these activities can be analyzed directly. For example, the results of empirical analysis show that the married individuals obtain higher marginal utility from sleeping time. The results of empirical analysis also show that the fare level at the arrival time or at the time of starting work influence the individual’s marginal utility with respect to the schedule delay of arrival, starting work, and sleeping.
This paper presents a latest inter-urban travel demand model for Japan. It intends the travel demand analysis for private business planning rather than government-based transportation planning. Cross-sectional data from the 2005 Interregional Travel Survey, Japan, is used for the model estimations. The model consists of three sub-models: a trip modal choice sub-model, trip distribution sub-model, and tip generation/attraction sub-model. The trip modal choice sub-model is a nested logit model including an upper tree choice of automobile and public transportation and a lower tree choice of rail, bus, and air transportation; the trip distribution sub-model is an aggregated logit model; and the trip generation/attraction sub-model is a log-linear regression model. The models are verified by comparing the estimated results with the observed data. The proposed model successfully reproduces the current travel demand.
Along with the forthcoming implementation of an electronic distance-based charging strategy for the freeways in Taiwan, a congestion charging strategy may also be designed to help alleviate heavy traffic. Unlike previous studies where the discrete choice models are used, this study applies the cusp catastrophe model to discuss the drivers’ route switching behavior given the various rates and describe their non-linear characteristics. A questionnaire survey was conducted to obtain empirical results with 461 valid questionnaires were collected from freeway drivers traveling in the Taipei metropolitan area. The proposed behavioral model considered “switching intention” as the state variable, with “switching barrier” and “congestion charging rate” as the control variables. The behavioral state analyzed samples located in six areas of the control space. The catastrophe characteristics of switching behavior were also discussed. Higher switching barrier could easily cause discontinuous switching behavior. A bimodality phenomenon occurred especially when the rate charged was NT$1.2/km.
The analysis of children’s activity-travel patterns has gained increasing attention in a variety of research fields. Most of the previous studies suggested that more compact development promotes less car-dependent travel among children. Unfortunately distinguishing what was a cultural artefact and what was a ‘universal’ truth of children’s travel is difficult as existing literature on children’s travel vary not just by country, but also by measures and analysis. The aim of this paper is to help bridge this gap of knowledge. Using the UK National Travel Survey and the Osaka Regional Area person trip datasets, this paper compares children’s travel behaviour in two countries with significantly different cultures. This paper discusses both consistencies and discrepancies of travel behaviours between the countries to highlight what factors are consistent despite cultural differences, and what may vary within cultures or different built environments.
With the development of Route Guidance System, travelers’ route choice behaviors change rapidly yet the existing modeling methods are not satisfactory. In addition, most existing models were formulated without integrating the driver’s attitude and preference in detail. In this paper, a new route choice model which can deal with the mentioned topics is proposed. With the combined concepts of hierarchical road classification and resource constraints, the paths they are not seriously overlapped are enumerated. After then, the model calculates the path choice probabilities with respect to the given preferred arrival time. Using a real-size network, the proposed model calculated path choice probabilities with Monte Carlo simulation.
This paper attempts to describe flexible temporal constraint as specific behavior on one-day shopping travel in Islamic countries, namely daily praying time constraint. In further, the paper take into account the constraint to develop a choice model of leave time from shopping place. The model is derived from minimization of three types of disutility that available during a traveler stays at shopping place and arrives at a destination place, i.e., disutility of shortage stay time at the place, disutility of lateness leave time from shopping place, and disutility of the time constraint as consequence of availability of the temporal constraint during period time of a set origin-destination trip. In order to estimate parameters values of the model, a trial and error process method based on simulation approach was applied. The model was applied to the two categories of shopping centre visitors i.e., car user and motorcycle user categories respectively. By using a goodness of fit test, the proposed model was acceptable. The parameters values show that response of the car users to start the praying activity is later than the motorcycle users. In contrary, durations of the motorcycle users to conduct the constraint activity are later or longer than the car user category. The flexible temporal constraint also can be applied to develop a departure time, trip pattern and mode choice model in further studies.
In Japan, population started to decrease with more elderly generations. Under such circumstance, estimating effects of new road has become significantly important in forecasting road transportation demand, using cost-benefit analysis, environmental effect analysis for political decision of planning national trunk road network. This study attempted to comprehend recent development in transport demand by vehicle, and to forecast future demand based on model analysis. The study found that vehicle transport demand for both passenger and freight vehicles have decreased; in passenger transport, driver's license holders have increased among women and the elderly. Number of trips by vehicle increased, and average travel distance has decreased due to increase of light passenger vehicles. Regarding freight transport, transport unit has decreased due to increase in value-added to carried goods.
The shift of travel demand policies from the conventional supply oriented policies to management oriented policies has made the effectiveness of conventional trip-based modeling approaches, which still dominates the practice, questionable. In addition to this, the increasing finical burden of the conventional PT-surveying is making the sustainability of the model doubtful. The attempts so far to reduce the cost mainly focused on finding alternative surveying methods and techniques. In this paper, however, we investigate how shifting to alternative models, tour-based model in this case, may contribute in reducing the cost burden of the conventional PT-surveying approach. We will also investigate future prospect of this approach.
This paper identifies the relative importance of variables influencing route choice using a neural network approach. Variables related to route attributes and choice contexts are simultaneously incorporated into the model, and a weight partition algorithm is employed to calculate the strength of influence on route choice decisions. The network is trained and validated using stated preference data. Simulation results show good predictability (97.4% of accuracy) of the neural network model. The relative importance of input variables indicates that road category, pricing, bonus and passing through an urban area are more important. Among all choice contexts, the size of truck is most important, followed by travel time difference and road length. The relative importance identified by the neural network model is consistent with the results of a multinomial logit model, and provide meaningful references for variable selection and model estimation.
This analyzes the effect of fluctuation of gasoline prices on transport behavior, to suggest a good example of application of the transport statistics. The method includes the multiple regression or the autoregressive error model, where the elasticities of gasoline price and the income are estimated, using the national time-series data from 1987 to 2008. Higher gasoline prices are shown to be related to lower auto passenger-km per capita, higher transit ridership, lower gasoline consumption on cars, lower auto ownership, and the purchase of more fuel-efficient cars. The effect on railway transport with or without periodic tickets is separately examined. The results not only suggest general policy implications relating to fuel tax, but estimate the adverse effect of the discounting of expressway tolls as well as that of the possible abolition both of the provisional gasoline tax rate and the expressway tolls which the new political leaders in Japan proposed.
Travel intention can directly or indirectly affects travel choices as well as personal attributes such as car ownership and income that important for future transportation planning of developing countries. This study hypothesized that the real travel intention is influenced by travelers’ personality and preference which are free from constraints. Car preference and two types of personality, environmental concern and frugal lifestyle, were selected as the important factors influencing travel intention of travelers especially in developing countries. High level of car preference induced commuters to choose faster travel modes, car and mass transits. Eco-friendly commuters had high intention to travel by environmental friendly modes. Conventional public transports are preferable modes of commuters who have higher level of frugal lifestyle. The intention to refrain from car use is higher for the commuters who have both eco-friendly and frugal personality. Besides, personality and preference also affected attitudes to travel of the commuters.
This study examines carrier choice for the intercity bus by using a latent class model with nested logit formulation, which allows similarities among carrier alternatives as well as individual preference heterogeneity. The stated preference experiments were designed based on a number of intercity bus attributes. Empirical data was collected from passengers who traveled on two major intercity bus routes in Taiwan. Empirical results indicate that all designed bus attributes were perceived to be important for choosing intercity bus carriers. Moreover, some intercity bus carriers had common unobserved components, making them closely competitive in the routes studied. Estimation of the preferred latent class nested logit model indicates a three-segment solution and that the bus passengers are generally willing to pay more for attributes such as on-board comfort and driver behavior.
This paper presents a dynamic user equilibrium process in TRANSIMS. While TRANSIMS is characterized by an activity-based travel demand model, it can also be used as a trip-based model by using origin-destination trip data with departure patterns. The main foci of this paper are to investigate TRANSIMS’s dynamic traffic assignment characteristics and to evaluate its convergence property associated with its traffic assignment methods. In a test network, various postulated equilibrium process scenarios are experimented and their convergence properties are compared. Dynamic user equilibrium convergence properties obtained from day-to-day evolutional approach are compared in a highway work zone case. Various dynamic user equilibrium analyses provide intuitions on model convergence and travelers’ behavioral characteristics.
The first aim of this study was to do an exploratory investigation of dimensions of attitudes toward car and public transport in six Asian countries (Japan, Thailand, China, Vietnam, Indonesia, and the Philippines). The second aim was to find out determinants of the dimensions as well as of the possible differences of attitudes across countries. Attitudes toward car and public transport by 1,118 respondents in six countries were measured by 31 beliefs in form of pairs of opposite adjectives. The results of principle component analysis yielded three factors of attitudes toward car and public transport, namely: Symbolic affective, Instrumental, and Social orderliness. The result of comparison between attitudes toward car and public transport in each country indicated that the contrary between car and public transport may transcend cultures. ANOVA also revealed that there were great divergences across countries in the all three dimensions of attitudes toward car and public transport.
The objective of this study was to develop models for forecasting ridership at an individual transit stop or route section. This study addressed fixed-route transit services provided by the Adelaide Metro in the Western Statistical Sub-division and estimated boardings in one direction (towards the city) during morning peak and inter-peak periods. It used accurate methods to allocate demographic and socio-economic data from census areas to service areas. Ordinary Least Square regression (OLS) and Geographically Weighted regression (GWR) models were used to develop the relationships between transit ridership and socio-economic variables, land use and levels of service. The models gave logical results for the bus and rail service areas with significant predictive accuracies. The most significant variables that influenced transit ridership included headway (waiting time), distance to the city, population density, percentage of students and median household income within the transit service area.
This paper investigates the fundamental features and relationships of vehicle ownership, vehicle expenses and household socio-economic attributes in a mid-sized city in Thailand, using household vehicle ownership data recently collected. In this study, private vehicle dependency is explored. Based on a broad analysis, household income is found to be an important factor associated with both car and motorcycle ownerships, but perform in different manners. An analysis of household vehicle expense shows that the amount of car expense is considerably larger than motorcycle’s, while total vehicle expense also takes a significant portion within the household income. Moreover, over three quarters of total vehicle expense in the study area is on fuel. At the end of discussion, several predictions and suggestions on vehicle ownership situation in the study area, including a debate regarding feasibility of introducing price mechanisms for controlling vehicle ownership and usage in the study area, are concluded.
This paper presents a modeling framework for the choice of activity type, timing and duration in activity scheduling. The traveler’s choice reveals a strong dependency on the time of day and the activities that have been pursed before the current choice. The traveler also exhibits forward-looking behavior, i.e. the traveler realize the impact of the current choice on the future utility and take into account the future utility that he can obtain. The focus of this paper is thus capturing these dynamics in activity scheduling and replicating the traveler’s daily activity plans. The activity scheduling behavior is formulated as a Markov Decision Process. Solution algorithms are developed for the model and numerical examples are presented.
The government of Ho Chi Minh City has a plan to develop the current Nguyen Hue avenue to the walking street. In order to evaluate the feasibility of the project, it is necessary to conduct the traffic impact assessment. By using the simulation technique, several scenarios have been developed to identify the relevant solutions for the traffic improvement in this area. The traffic assessment is conducted via a process of OD demand analysis by using four-step model, which is improved from the previous model, HOUTRANS (2004) (The Study on the Urban Transport Master Plan and Feasibility Study in City Metropolitan Area). The proposed scenario, which can be considered as the most relevant solution for this project, is to convert some roads around Nguyen Hue avenue into one-way streets. Specifically, Ton That Thiep, Ngo Duc Ke street and Nguyen Hue avenue are changed into one-way streets in the direction of Pastuer and Dong Khoi street. Hai Trieu, Mac Thi Buoi, Huynhh Thuc Khang street are converted into one-way streets in the opposite direction.
Weather has an influence on our everyday life, travel and out-of-home activity participation. Especially many cities in East Asian countries including Japan have much rain. This paper focuses on travel behavior of university students on rainy days and attitude towards rain. We conducted a questionnaire survey for university students and staffs in a total of ten cities from eight East Asian countries and made an international comparison of their behavior and attitude. The number of sample is not so large but we got some interesting results. Although main travel mode is very different between cities, it did not show much variation for each city between fine days and rainy days except for bicycle in Tokyo. Trip frequency on rainy days was less than that of fine days depending on trip purpose. There was significant difference in activity schedule in the morning between fine days and rainy days. Lastly difference in attitude towards rain among countries was discussed.
By promoting the international transportation demand, the Asian Highway plan was expected to make considerable economical effects in the North-East Asian region. The study focuses on a part of AH1 route (i.e., South Korea-North Korea-China) and aims to analyze and forecast the variations of mode shares between South Korea and China due to the open of AH1 route. The study was performed using two main methods. First, a stated preference survey was performed to derive the actual modal share of each travel mode. Second, a disaggregate analysis was performed to develop possible mode-choice models for international passenger travel and find out the suitable choice. The results showed that the construction of the AH1 route would significantly affect the future international passenger travel modes.
Despite its successful applications in mode choice modelling, the Neural Network (NN) Approach is often seen as a poor technique for trip distribution estimation. However, empirical results from this study show that the NN can also be used as a good trip distribution modelling tool, by using appropriate Training Algorithm (TA), which is the most critical property of NN. This study will describe the results of NN approach in work trip distribution estimation with three different TAs, namely Back Propagation (BP), Variable Learning Rate (VLR), and Levenberg-Marquardt (LM). The experiments were conducted 30 times for each TA. The results suggest that both BP and VLR models tend to have overestimated total trip numbers, while LM model generates the closest total trip number to the observed one, with less than five per cent difference. Statistical analysis also suggests that LM model is able to generate a consistent performance, while other models have a great fluctuation. Then, the findings from this study are expected can be used as an important consideration for using NN approach as an alternative simple and robust travel demand modelling tool.
Nowadays, the use of information and communication technology (ICT) is infiltrating to the daily comings and goings of life. This study investigates the effects of ICT use on time planning, social dimension and travel behavior particularly in the context of Metro Manila, Philippines. The data was collected for university students and workers. The result of structural equation modeling indicates that ICT use may have a direct effect on time planning, social network, social activity participation and only indirect effect on travel behavior. Travel behavior may be directly affected by social network, social activity participation and time planning. The implications of the empirical results from a developing country like the Philippines to transport policy analysis, especially by time planning, is that some tasks are especially done in quick time planning due to ICT use as a tool, which might lead to new organization of activities as well as new patterns of travel.
Motorization in Asia is characterized by rapid growths in motorcycle and car ownerships and their interactions over time. An important question is when the people switch from motorcycles to cars and what influential factors are. To help answer this question, this study tried to examine historical trends in car and motorcycle ownerships and their relationship over development stages for selected countries using the national and provincial data. The findings suggested that at the first stage the high level of motorcycle ownership might accelerate the growth in car ownership, but at the later stage it could dampen further growths in car ownership. In other words, households in the developing countries would adopt multi motorcycles rapidly at low income levels and then quickly adopt their first cars; however, their decisions to buy the second or third cars may be delayed or canceled by the appropriate use of the existing motorcycles.
The Korea Expressway Corporation collects tolls in all expressways in its charge under the Toll Road Act establishing user pay principle, cost recovery method, and integrated-profit system as legal bases for collecting tolls. However, the act does not clearly stipulate the methodology how to measure the connectivity in terms of transportation, which is one of requirements for the adaptation of integrated-profit system, so that there have been lots of arguments on collecting tolls on the expressways. Thus, this research effort developed a transportation-connectivity index to estimate the degree of the connectivity of expressways in terms of physical linkage and actual usage. The index was validated using TCS and Hi-Pass data collected from expressways operated under the closed-type toll collection system. Conclusively, the connectivity indexes of the subject expressways in use are over 2.0 in general, which mean all the subject expressways are physically well connected and multiple expressway routes are frequently and simultaneously used.
This paper reports a study of a parking demand study of Chulalongkorn University campus in Bangkok, Thailand. We interviewed 130 student commuters who regularly park on streets nearby campus and a parking structure on campus. The survey data were analyzed using discrete choice techniques, and the binary logit model was estimated by maximum likelihood method. The results show that trip characteristics, such as arrival and departure times, are significant determinant of parking choice. In addition, attitudes toward parking facility’s attributes, including security, cover, and parking availability, also influence choice of parking, as does the type of tariff payment. The results of this study can be used to properly design parking service attributes of the university’s parking structure in order to attract drivers from on-street parking which causes traffic problems in the surrounding areas.
In this study, a multi-modal transportation system of Bangkok Metropolitan Area (BMA) is setup and calibrated for evaluating the impact of different congestion pricing schemes. In the proposed model, auto and public transport demands will be assigned separately to the same network for finding the utilities of travel. Based on the travel utilities, captive and non-captive demands for auto and public transport are estimated by nested logit model or elastic demand functions. 8 different congestion pricing schemes are tested on the current and future networks of BMA for choosing the most beneficial scheme for the next 20 years with the consideration of demand growth and extension of railway lines. The result suggested that congestion pricing scheme with the combination of radial, inner-cordon and outer-cordon tolls gives the best performance in shifting auto users to public transport and, reducing the congestion of network.
A heuristic approach is presented to solve allocation problem of distribution system, which is characterized as Minimum Concave-cost Multi-commodity Flow (MCMF) problem. Such MCMF problem is differentiated into uncapacitated and capacitated problem, as well as single and multisource network. This researh proposes solution of solving capacitated and multisource problem, while Gallo’s algorithm of solving single source and uncapacitated problem is treated to verify the proposed methods. The multisource and uncapacitated problems are solved by bilevel programming which is basically based on the theorem of Destination Spanning Tree, while the capacitated one is solved by linear approximation. Linear approximation is also used to solve uncapacitated problem and confirm the result of bilevel programming. Both methods are represented in Network Representation technique, in which some dummy nodes and links are added to the physical network in order to represent all components of mathematical model. Some cases are discussed to show the application of both methods.
The dramatic decrease in global demand due to the financial tsunami of 2008 forced the ocean container carriers (OCCs) to re-examine their maritime marketing strategies. In an attempt to help the OCCs establish effective marketing strategies, this study conducted a survey regarding the ocean freight forwarders’ (OFFs) needs on the OCCs’ service. An evaluation framework with 21 attributes was developed based on the concept of marketing mix. The fuzzy Delphi method and DEMATEL were adopted to synthesize the OFFs’ opinions and examine the perceived causal relationships between the attributes. The analysis results showed that sales representative’s expertise and transportation reliability are the most important attributes valued by the OFFs instead of transportation fee. The OFFs with various characteristics have different perspectives on the importance of attributes and their causal relationships. The results reflect the distinct capabilities of handling cargoes and negotiation powers in dealing with business partners of various-sized companies.
With the development of food industry and food refrigerated transport, all kinds of refrigerated containers are becoming more and more popular. But the decay of perishable food takes place often due to improper loading and unreasonable design of air flow organization. Based on analysis, experiments and simulation with Fluent software, this paper studies the temperature field and air flow inside the refrigerated container in certain loading conditions. The results show that different inner temperatures need different air blowing-in velocities in order to obtain more uniform temperature field. And the blowing-in velocities have the different influences to different positions inside the container. The increase of blowing-in velocity is beneficial to the uniformity of the temperature field. The conclusions and suggestions are of reference value to the design and operation of refrigerated container.
The vehicle routing problem (VRP) has received a lot of attention and has been applied extensively in the field of logistics. In practice, the heterogeneous fleet is usually used at the distribution center. The need for different types of vehicles is determined by the characteristics of the customers. Hence, the heterogeneous fleet vehicle routing problem (HVRP) which minimizes the sum of fixed vehicle costs and variable routing costs is an important variant of VRP. The HVRP is a NP-hard combinatorial optimization problem that is very difficult to solve optimally within reasonable time. The ant colony optimization (ACO) algorithm has been applied to the VRP successfully, but much less for VRP variants. Therefore, this research aims to develop a two-stage ant colony optimization (TACO) algorithm to solve the HVRP. The TACO was tested on two sets of benchmark instances in the literature. The results show that the performance of the TACO is competitive with the state-of-the-art algorithms.
The delivery of goods from a warehouse to local customers is an important decision problem of a logistics operator. As the demand is fluctuating, the common carrier may be needed if the private fleet is insufficient. In this study, we focus on the vehicle routing problem with private fleet and common carrier (VRPPC). In order to balance computational load and solution quality, a heuristic algorithm is developed based on several classical mathematical programming techniques. The VRPPC is first formulated in the form of the set covering problem, and the Lagrangian relaxation is used as the backbone in designing the iterative algorithm. In addition, a concept similar to column generation is used to update the solution space, a partial set of routes. Based on the numerical experiment, the solution quality of the heuristic algorithm is stable, and the computation time is acceptable under the current highly dynamic environment.
The on-line vehicle routing problems (VRP) is an extension of VRP in order to consider real-time requests as well as possible variations travel times in the network. In this research, a solution algorithm for solving on-line VRP is proposed. The solution algorithm is divided into two phases, off-line route planning and on-line route updating. In the off-line phase, a time-dependent VRP formulation is constructed to assign initial routes. In the on-line routing phase, a hybrid heuristic approach with tabu search and genetic algorithm is proposed to handle real-time requests and to improve routes under real-time information. The simulation-assignment model, DynaTAIWAN is applied to evaluate assigning and routing strategies in a traffic network. Numerical experiments are conducted in a Kaohsiung city network.
This paper considers a multi-plant and multi-distribution centers (DCs) supply chain distribution network (SCDN). The decisions are to locate the open DCs, allocate customers to DCs, and DCs to plants to minimize the total logistics cost including the fixed costs and warehousing cost of DCs, and shipping cost from plants to DCs and from DCs to customers. Also, it takes workload balance requirements into consideration to avoid those open DCs being congested or idle. A bi-level programming model is proposed to deal with this problem. The upper level considers DC location problem and production-allocation problem. The lower level focuses on allocating customers to DCs such that the workload of each open DC is balanced. We propose a double threshold accepting (TA) approach to solve this problem. Four different examples are tested and the results show that our double threshold accepting algorithm can obtain a good solution efficiently.
In order to satisfy the transportation demand for elderly and disabled people, providing efficient dial-a-ride systems is an important issue. Appropriate vehicle routes for dial-a-ride systems can increase transportation efficiency and reduce the operation cost. Most literatures focus on improving the vehicle routing and scheduling and assume that the travel time is a constant value. However, the travel time can fluctuate dramatically due to traffic congestion or incident. Using the constant travel time to solve dial-a-ride problems (DARP) cannot obtain the efficient vehicle routes. To consider the variation of the travel time, this paper formulates a mixed integer programming formulation for the time-dependent DARP with time window. In the formulation, the travel time variations are treated as step functions. The simulation-assignment model, DynaTAIWAN is applied to generate time-dependent travel time matrices and simulate traffic flows in the real network. Numerical experiments are conducted in a Kaohsiung network.