The identification and ranking of hazardous road locations are important parts of road safety improvement programs. This paper describes the application of Empirical Bayes (EB) approach for identifying and ranking hazardous junctions. Accident, traffic, and junction geometric/environment data from 203 four-legged and 186 three-legged signalized junctions across western part of Singapore were collected. Accident prediction models were developed and safety of the junctions was estimated. After that, hazardous junctions were identified using probability of selecting the worst site concept and then ranked using PSI (potential for safety improvement) and LH (level of hazard) criteria. A total of 38 junctions were found as hazardous. The result shows that the use of PSI criterion is more favorable than LH criterion as it is better able to detect the top hazardous junctions with the largest number of accidents in the study period.

View full abstract

The simultaneous impacts of driving experience and use of in-vehicle traffic safety information on traffic safety was investigated in this study, focusing driving behavior of young male drivers. To evaluate this influence, the utility function of the information was first defined by incorporating the influence of driving experience based on the forgetting phenomenon in the short-term memory. By putting this utility function into a driving stability risk model which was built by an ordered response modeling approach based on drivers' speed choice, the level of traffic safety was measured. The estimated results show that driving experience is associated with better recall of the provided in-vehicle traffic safety information, showing that risk of driving could reduce by provision of the safety information. Data used for the analysis was collected through an on-site driving experiment using a probe vehicle, which was conducted at a signalized intersection approach with a limited traffic signal visibility on the national highway “route 2” in Hiroshima City, Japan in 2006.

View full abstract

The concept of predicting road crashes in real-time is influenced by the idea that instantaneous crash probability can be fathomed using the instantaneous traffic flow data and thus road users can be informed about the existence of any hazardous traffic condition in real-time as part of proactive safety measure. This paper presents a methodology for building such a model for urban expressways using Bayesian Network. Sixteen month (December, 2006 to March, 2008) crash data and 24-hour traffic data (5 minute aggregated average speed and cumulative flow) were collected for a two kilometer study section on Shinjuku 4 Tokyo Metropolitan Expressway. The model was built with 150 field crash data and later validated with 50 separate crash data taking place on the same road section. The outcome was encouraging as the newly developed model could successfully predict 74% future crashes using average crash probability as the threshold value.

View full abstract

Driving behavior such as speed reduction is needed for risk aversion while driving although the behavior leads to the decrease in travel utility. In this paper, a driving behavior model applying “Subjective Risk” and “Driving Utility” is proposed as a fundamental study for the evaluation of traffic safety measures considering the trade-off between safety and travel utility. Then, the mechanism of the changes in “Driving Behavior”, “Subjective Net-Utility”, and “Social Net-Benefits” due to the changes in traffic environment is proved. Finally, the applicability of the model is confirmed with the data observed at non-signal intersections. It is found that the model can be applied to comparing the level of “Subjective Risk” and that the assumption is verified.

View full abstract

In order to improve traffic flow, signal-free, grade-separated intersections in Delhi have often replaced signalized intersections. Evaluating the impact of signal free intersections on pedestrians is important when nearly fifty percent fatalities in the city involve pedestrians. Examining a pedestrian sample before and after site reconstruction produces a better understanding of the subsequent changes in pedestrian risk behavior. Strategically placed camcorders viewed pedestrians and approaching traffic. Data reduction measured the accepted time gap of each pedestrian making an unsafe crossing and the average speeds of the approaching vehicle groups. A pedestrian survey provided additional information. Sixty two percent pedestrian accepted gap less than 4 seconds(exposed to high risk) after site reconstruction compared to fifteen percent pedestrian accepting similar gap before the site reconstruction. More than 35 percent of pedestrian stage crossings had accepted gaps less than one second as compared to 6 percent of pedestrian stage crossings before reconstruction. After reconstruction, 22% of pedestrians did not use the pedestrian underpass and continued unsafe crossings at the site. Pedestrian exposure to greater risks of bodily injury and death with site reconstruction occurred despite the presence of an underpass and median barrier. Pedestrians had exposure to higher risks after the construction of the signal-free crossing. Not all pedestrians used the pedestrian subway. The design and location of the pedestrian subway needs modification.

View full abstract

Road traffic injuries have become a serious health burden all over the world in general and in cities of low and middle-income countries in particular. Delhi, the capital city of India, records the highest number of road traffic fatalities of all cities in India. This study evaluates the effectiveness of the mandatory seatbelt law enacted in Delhi in 2002 in terms of observance of the law and estimated reduction in fatalities due to road traffic crashes. Seat belt use was monitored by road side observations at one location in 2001one year before the compulsory use law. Road side observations on belt use were taken every year in March/April for the period 2002-2005 after the notification of the compulsory use law. Seat belt use by front seat passengers averaged 72% for the four years 2002-2005 (drivers 79%, passengers 58%). Belt use by front seat by passengers was about 25% lower than that by drivers in all the years. Since car occupants comprise only 2%-3% of the fatalities in Delhi, the belt law may have resulted in an overall fatality reduction of less than 1%, an estimated 11-15 lives per year.

View full abstract

This paper explores the accident insurance system in Indonesia in which the fund is collected through compulsory contribution from vehicle owners to cover victims of traffic accidents. It criticizes the system for being outdated in concept and contains a serious common cost phenomenon. The determination of the rate of compensation and hence the contribution is arguably low which practically has little effect on the safety consciousness among road users. Institutionally, Jasa Raharja, a state owned company, has become a less responsive organization for being the only party managing the fund on a monopoly basis. The study suggests to reform the above system into a third party-insurance scheme as applied in many countries so that a more accountable system can be created. Higher value of compensation leading to high premium would suggest the drivers to drive more carefully, and more funding can likely be made available.

View full abstract

An accident is defined as an incident which involves one or more vehicles on a lane of road and causing losses of properties, injuries and fatalities. Accident could be caused by several factors, such as human behavior, vehicles, road conditions, and environment. This research is intended to identify the accident characteristics, to identify accident black-spots, and to obtain the relationship between accident rate and traffic characteristics and road geometry in two different topographies, lowland and highland regions. The location as a case study is Malang District (located at East Java Province). The results shows that the changing of traffic characteristics and road geometry could significantly increase or decrease the accidents occurrence rate, however the different results were obtained from different types of topography. In this study, several black spot locations in highland and lowland regions and some important accident characteristics in Malang District were identified.

View full abstract

In Thailand there are more than 100,000 traffic accidents and traffic-related casualties of approximately 12,000 deaths per year. The aim of this research is to mitigate or reduce the severity and the number of road accidents, especially rear-end collisions. This research implemented the DOT tailgating treatment pavement markings to assist drivers in establishing the recommended following distance. The recommended following distance is derived from asymptotic stability condition of the GM 5th car-following model and calibrated with data collected on the national highway 1141, Thailand. The relationship between flow rates and distance headways were investigated before and after implementing the DOT treatment pavement markings. Distance headways are then used as a measure to examine the effectiveness of the markings. It is found that for a given flow rate distance headways increase after implementing the markings or the likelihood of rear-end collisions is reduced at the study site.

View full abstract

This study aimed to find the effects of road geometry and cross section variables on the number of accidents. In addition this study developed a methodology to combine variables using decision trees. Combination variables for road geometry and cross-section variables were developed using the Chi-squared Automatic Interaction Detection (CHAID) algorithm. Three Negative Binomial models were developed: two with homogeneous road segments, and the other with 1-km road segments. The accuracy of Negative Binomial models developed with different road segments was compared. The Negative Binomial model using homogeneous road segments based on horizontal alignment was found to be the most accurate of the three models. Combination variables showed a significant effect on the number of accidents. It was found that the number of accident in a road segment is influenced by the average accident rate in the adjacent road segments.

View full abstract

This paper presents the effect of traffic and roads conditions to the accident rates on rural interurban roads in Eastern Indonesia. The survey was conducted in 7 provinces on 35 sections of roads. However, is only 18 sections of roads were able used for constructing the accident rates model. The multivariate regression linier with Poisson error was chosen as the best models and it concluded that the proportion of motorcycles, roughness index, road width and average speed are contributing significantly to the fatality rate in terms of fatalities over 100 million vehicle kilometre travelled. It is suggested that by limiting the number of motorcycles will have a greater impact to road safety. Increasing proportion of motorcycles by 10% will increase fatality rate by 30%. Reducing road width by 0.5 m, increasing average speed by 5 kph and increasing IRI index by 1 will increase fatality rate by 8.50%, 3.50% and 2.80% respectively.

View full abstract

In this paper, we focus on the international dry bulk freight rates, make qualitative analyses on the composing factors of the dry bulk shipping market, and investigate the features of mutual action of the world dry bulk demand and supply, sum up the features of the present shipping market. Meanwhile, we make a series of quantitative studies on the existence, nature and magnitude of regularity, transportation costs, supply and demand relationship, economy and trade, seasonal factors and the political environmental factors by SEM--structural equation modeling. And the path coefficients of factors are calculated through data analysis, by which we explain the relationship between the major factors; provide a strong basis for the analysis and forecasting the international dry bulk freight rates.

View full abstract

In this paper, a method integrating Q-learning algorithm and simulation technique is proposed to optimize the operation scheduling in container terminals. Firstly Q-learning algorithms for yard cranes and yard trailers are designed to obtain the optimal scheduling strategy of yard cranes and yard trailers. Then Q-learning is combined with simulation to develop an integrating scheduling model includes all stages of operation process. In this method, simulation model is used to construct the system environment, Q-learning algorithm is used to learn the optimal dispatching rules for equipments, and the optimal scheduling scheme is obtained by the interaction of Q-learning algorithm and simulation environment. Finally, numerical tests are used to illustrate the validity of the proposed method.

View full abstract

Under deregulation, the competition for air general cargo business between all-cargo airlines and combination airlines is foreseeable. This paper proposes a model structure that analyzes the pricing and service strategies between two kinds of carriers within a competitive framework, and evaluates airline profits based on game theory and a microeconomic theory of airline behavior. The model is applied to a case study, with empirical airline operation cost data, and acquire some results. The results show that combination carriers mostly have significant dominance over the market and might expand their freight aircraft fleets for competition. All-cargo airlines could expand their operation via better service in the markets, especially where combination airlines provide insufficient shipping capability for air cargo service.

View full abstract

This research intends to carry out study on the strategy of improving the operating performance of container terminal from the software aspect through quantitative simulation model. Shipping strategic alliance is popular in recent years and it is anticipated to base on the improvement strategy on berth to enhance the operating performance of container terminal. This research applies three evaluation indicators (average waiting time, waiting time factor and the author create indicator) to evaluate the operating performance with three different schemes (berth charter, berth exchange and common berth). The research results show that no matter which type of the above evaluation methods is adopted and according to the research on the sample cases of shipping companies the operation performance of the scheme of common berth is most significant.

View full abstract

In this paper, a new method to measure the passing capacity of coastal waterway channel is proposed considering service level by computer simulation technique. The passing capacity of coastal waterway channel is first defined by the number of standard ship passing the channel at the required seaport service level. Then the conversion coefficient between the standard ship and other ships is given, which will provide theoretical bases for design, planning and extension of seaport channels. Finally, an application is presented to evaluate the proposed method, and the results show that the larger the ship, the more efficient the waterway channel.

View full abstract

In order to cope with the ever-increasing competitive environment and enhance the overall competitiveness of ports in a region, cooperation between adjacent container ports is emerging. The main purpose of this paper is to explore causal relationships between influence factors, types of port cooperation (i.e. complementary cooperation and coopetition), and port competitiveness. Besides, potentially important items for port cooperation are also identified. The results indicated that both two types of port cooperation would positively influence the competitiveness of adjacent ports in same region. Moreover, competitive intensity in a region would support through both types of cooperation to influence regional competitiveness indirectly. Shipping and terminal operators' strategy would also influence regional competitiveness through both types of cooperation indirectly. Finally, port internal conditions, liners service and pricing strategy are identified as important items for complementary cooperation and that for coopetition are port operational management, liners service, resource integration and pricing strategy.

View full abstract

Significant changes in the shipping market cause port authorities facing new challenges and opportunities. Container traffic to and from other parts of Asia is expected to grow more rapidly than the world average, and the intra-Asian trade in particular will continue to outperform global container growth. The purpose of this paper is to explore the relationships among major Asia ports based on the historical port throughput data by using a set of time series analysis. The results would assist port authorities concerned in understanding the port position and managing the partners. The findings indicate that there were no long-term equilibrium relationship existed among Asia ports, but short-term relationships did exist among them. Through generalized forecast error variance decomposition, it is found that many of these ports can explain the variance with each other which may help port authorities to gain more insights about the sources of errors in throughput forecasting.

View full abstract

This study aims to empirically investigate customer satisfaction in China low cost carrier (LCC) market. Three importance-performance analysis (IPA) methods — traditional IPA and two revised IPA (partial correlation model, PCM and dummy regression model, DRM) are adopted and compared. The results show that the top-priority attributes to be improved recognized by the traditional IPA are Flight on-time and Complaint response, which are different to those suggested by PCM-- Complaint response and Meal service. In addition, according to the evaluation results of DRM on the passengers with various journey purposes, Attributes importance viewed by passengers with various journey purposes significantly differs. Corresponding improvement strategies are then proposed based on three methods.

View full abstract

This paper seeks to improve our understanding of air passengers' decision-making processes by testing a conceptual model that considers service value, airline service quality, satisfaction, perceived sacrifice, and behavioural intentions. In this study, a linear structural equations modeling system is applied to incorporate the service quality of airline companies into the passengers' airline choice models to enhance the models' performance and the forecasting ability. Two modeling approaches are applied in this research: the structural equation modeling (SEM) and the importance-performance analysis (IPA). The SEM results of this study show that the service value is the major factor that can influence the behavioural intention. IPA results indicate that responsiveness is the most important airline service quality attribute in passengers. Finally, implications of these results for practice and research are provided.

View full abstract

Due to the capacity constraint of Haneda Airport, airlines in Japan have to rely on large-size aircrafts to increase capacity for transporting increasing volume passenger in domestic aviation. Consequently the average aircraft-size has been unusually large in Japanese domestic market in comparison with the other western countries. This means that level of service in terms of the flight frequency is low in many air routes in Japan. In this study, first, we broadly compare the flight frequency and aircraft size among major countries. Second, in order to get an idea on the potential flight frequency, we analyze the flight frequency in US and Japan from taking into account the characteristics of each air route such as passenger demand, route distance and number of airline entries. The study results, though based on simple quantitative analysis, provide valuable insights for policy makers concerning future strategies in expanding capacity of Haneda Airport.

View full abstract

This research employs AHP questionnaires to survey cargo airlines in Taiwan, and to identify the most important service attributes and the performance of the Taoyuan international airport (CKS) on these attributes. Of the many service attributes that influence an airlines' cargo hub airport selection behavior, "geographical location of airports" is perceived as the most important service attribute, followed by congestion and delay, operational availability, bilateral agreement, local demand, political risk, and airport user charge. According to previous literature, these above-mentioned attributes are some of the most frequently reported service attributes which influence an airlines' hub airport's selection behaviour. However, this research is one of the few researches that rank the importance and performance of the hub airports' service attributes using an empirical study through surveying major air cargo carriers in Taiwan.

View full abstract

Using data gathered from domestic public-use airports in the Philippines, a model of the inter-relationships among quantitative measures of airport accessibility, air passenger movement, and the configuration of urban space around airports was calibrated. Surveys on selected airports confirmed that a stable airport hinterland exists, which is significantly related to trip origins of departing air passengers. A measure of airport accessibility based on the location of population centers at specific distances from the airport is thus defined. Data from multi-airport regions show that population density around airports in the Philippines follow a systematic decay function, suggesting a pattern of concentration near the airport. This pattern can be adequately predicted by a function of airport accessibility index, characterizing the observed trend towards settlement concentration around airports.

View full abstract

The container handling operation is a critical issue that affects the throughput of the container yards. This paper focuses on determining the storage position of the reshuffled container during retrieving containers at container yards. The static problem is considered, i.e., the sequence of the retrieved containers is known, and arriving containers is not allowed during the period of retrievals. The objective of the problem is to retrieve all containers with the minimum number of reshuffles. A tabu search (TS) algorithm is proposed to solve the problem and a simple branch and bound (B&B) procedure is applied for comparison of the solution quality. 60 sets of instances are randomly generated for testing the efficiency of the proposed TS. The computational results show that the average gap between TS and B&B is 0.4% from the tested instances and the computational time is effective.

View full abstract