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Containerization has greatly reduced the cost of international trade by increasing the speed of cargo turnover. However, many empty container movements have been generated by the imbalance of international cargo movements between ports and hinterland importers and exporters. Currently, loaded containers carry only import and export cargo. Little work has been done on the utilization of empty containers to carry regional cargo. There is great potential to use empty containers to carry regional cargo. This study developed a mathematical model of the use of empty containers to carry regional cargo. The model considered quantities of cargo located at the origins and destinations of empty containers, together with cargo that could be consolidated en route. The financial return on investment was calculated as a benefit–cost ratio to determine the suitability of the available empty containers to carry regional cargo. Operational data from a haulage company were used as a case study to increase the reliability of the results. It was concluded that if managed optimally, carrying regional cargo in empty containers should be profitable. In the particular case reported in this paper, operational profit was guaranteed when a haulage benefit–cost ratio of 3.05 was achieved.

This study investigates the relationship between drivers' eye movements and their driving performance, when drivers interact with in-vehicle systems. The impact of a set of in-vehicle visual tasks (VT) on drivers' workload, task performance and eye movements was studied in an on-road experiment with 41 subjects (29 male and 12 female), using an instrumented vehicle. The degree of distraction was differentiated into three groups by cluster analysis based on two sets of selected drivers' eye movement parameters. The results showed that the in-vehicle VT had a negative effect on driving performance, accompanied by a change in drivers' visual behaviour, including a reduction in speed, a higher speed deviation and less predictable steering behaviour. At the same time, a decrease of looking ahead was replaced by viewing the touch screen, and a significant increase in drivers' saccade was observed as the task difficulty level increased. The groups that were the most significantly affected by VT demonstrated a significantly worse driving performance. It is therefore concluded that the deteriorated performance caused by distraction can be diagnosed by visual behaviour change, and it is possible to use eye movements to monitor the change in driving performance.

In-vehicle information systems (IVIS) can be controlled by the user via direct or indirect input devices. In order to develop the next generation of usable IVIS, designers need to be able to evaluate and understand the usability issues associated with these two input types. The aim of this study was to investigate the effectiveness of a set of empirical usability evaluation methods for identifying important usability issues and distinguishing between the IVIS input devices. A number of usability issues were identified and their causal factors have been explored. These were related to the input type, the structure of the menu/tasks and hardware issues. In particular, the translation between inputs and on-screen actions and a lack of visual feedback for menu navigation resulted in lower levels of usability for the indirect device. This information will be useful in informing the design of new IVIS, with improved usability. STATEMENT OF RELEVANCE: This paper examines the use of empirical methods for distinguishing between direct and indirect IVIS input devices and identifying usability issues. Results have shown that the characteristics of indirect input devices produce more serious usability issues, compared with direct devices and can have a negative effect on the driver-vehicle interaction.

In recent years, the issue of usability of in-vehicle devices has received growing attention. This is in line with the increase in functionality of these devices, which has been accompanied by the introduction of various new interfaces to facilitate the user–device interaction. The complexity and diversity of the driving task presents a unique challenge in defining usability: user interaction with in-vehicle devices creates a ‘dual task’ scenario, in which conflicts can arise between primary and secondary driving tasks. This, and the safety-critical nature of driving, must be accounted for in defining and evaluating the usability of in-vehicle devices. It is evident that defining usability depends on the context of use of the device in question. The aim of this review therefore is to define usability for in-vehicle devices by selecting a set of criteria to describe the various factors which contribute to usability in this specific context of use.

The role of the driver in the longitudinal car following control task will change from operator to supervisor with most of manual control replaced by automation as adaptive cruise control (ACC) technologies become commonplace. The extent to which manual control can be replaced by ACC will be determined by many factors. An important issue is the compatibility between ACC performance and the driver’s expectations. This paper describes the results of a simulation study of the performance of ACC relative to driver expectation. Driver’s expectation is quantitatively defined as the expected deceleration rate for several time-to-collision (TTC) levels, and an absolute minimum TTC that drivers tried to avoid in all cases. A two-level ACC algorithm was used to simulate the performance of an ACC equipped vehicle in various scenarios, and the result was compared to the driver’s expectations. The investigation has focused on scenarios which ACC is able to manage technically, but where driver expectations might be breached. By systematically changing variables such as the parameters of the ACC algorithms, traffic scenarios and time-headway settings, a large number of situations have been tested. The results have revealed that whilst appropriate ACC settings can be found which will meet the driver’s expectations, the ACC settings that are most capable in a range of traffic conditions are not necessarily the most user-friendly. A discussion on the implications of the findings is also presented.

The shipping industry is under a great deal of pressure from different sources to improve the safety records, and reduce the number of accidents at sea. Human element has been identified and accept...

This paper deals with a short-term liner ship fleet Planning (LSFP) problem with container shipment demand uncertainty. Assuming that container shipment demand between any two ports on each ship route follows a normal distribution, this paper develops an integer linear programming model with chance constraints for the LSFP problem and proposes a two-phase heuristic algorithm for solving the large-scale LSFP instances. Finally, numerical examples are used to show application of the proposed model and evaluate the performance of the two-phase heuristic algorithm.

The “Reading Area Transport Information Network” project has been focused on the delivery of an enhanced unified communications network for Reading Borough Council using WiMax/Wi-Fi and on the use of the latest 3G communication capability to better deliver existing transport services and to provide a platform for the delivery of enhanced services in the future. The in-vehicle navigation sub-project reported is the first UK development project on vehicle navigation using real-time traffic information, which involved the development of a navigation system which integrated real time traffic information on delays and incidents from city council's Urban Transport Management and Control (UTMC) system with a satellite navigation system. Using portable computer as a platform, the in-vehicle navigation service was trialled by professional drivers on their delivery journeys between an out of town depot and a town centre store in Reading. The technical reliability and user acceptance of diversion routes provided by the navigation system to avoid congestion were evaluated. The results demonstrated the feasibility of integrating UTMC traffic information into in-vehicle navigation systems.

The research reported in this paper is an empirical observation of driving behaviour on a sea-crossing bridge. A microscopic simulation model was validated using the observed data, which was used to investigate the traffic operation on sea-crossing bridges. It is believed that understandings obtained from the empirical modeling of driving behaivour are also applicable to many other large scale sea-crossing bridges. The simulation model validated to the empirical data is very useful for the development of be-spoken traffic control and management strategies of bridge traffic operation.

This paper reported an deployment and evaluation study of an enhanced unified communications network using WiMAX for Urban Transportation Management and Control (UTMC) communication. The technical feasibility and capability to provide connectivity with the traffic control and surveillance equipments using the alternative wireless network was demonstrated and evaluated through in a demonstration trial at Reading, UK. The results confirmed that the multicarrier interface was able to effectively transfer traffic signal control and CCTV streaming between on-street stations and UTMC center. It was found that the wireless connectivity could provide reliable and cost-effective data services than those provided by the commercial wired network

This paper describes the investigation of traffic operations on both dedicated and open e-Lanes. The scenario is regarded as a migratory stage towards eventually full automation of urban principal road traffic operation. The traffic operations were investigated using a be-spoke microscopic simulation model. It was found that under certain Dual Mode Vehicle (DMV) demand level and at certain headway policy, the open e-Lane operation can be further improved by migrating to a dedicated e-Lane operation.

Current traffic microsimulation tools are usually of limit use for evaluating the operations of pedestrian-involved systems, especially under unsignalized conditions (e.g. jaywalking and mid-block pedestrian crossings are not typically modeled), due to insufficient understandings of Pedestrian-Vehicle Interaction (PVI) behavior at such locations. This paper studies pedestrians' gap acceptance behavior when they jaywalk outside crossing facilities, which is regarded as the most basic and important part to improve current PVI behavior models. A field study was conducted to collect the data of pedestrians' decisions and concurrent traffic status using a set of synchronized video cameras on a typical unsignalized urban road section. The data were used to develop and validate a pedestrian gap acceptance model based on discrete choice approach. The initial results with the model are appealing when considered in combination of simplicity and accuracy. The results can be used to supplement existing guidelines for pedestrian-involved problems, or to form a knowledge base to incorporate pedestrians into current vehicle-dominated microsimulation models in a more realistic way.

Usability must be defined specifically for the context of use of the particular system under investigation. This specific context of use should also be used to guide the definition of specific usability criteria and the selection of appropriate evaluation methods. There are four principles which can guide the selection of evaluation methods, relating to the information required in the evaluation, the stage at which to apply methods, the resources required and the people involved in the evaluation. This paper presents a framework for the evaluation of usability in the context of In-Vehicle Information Systems (IVISs). This framework guides designers through defining usability criteria for an evaluation, selecting appropriate evaluation methods and applying those methods. These stages form an iterative process of design-evaluation-redesign with the overall aim of improving the usability of IVISs and enhancing the driving experience, without compromising the safety of the driver.

This paper reported results of an on-road evaluation study of three types of voice interfaces, the traditional voice system, and two intuitive voice systems with text prompts on a central display and on a cluster display respectively. The effects of voice interfaces were evaluated based on primary driving and secondary in-vehicle task performance. The in-vehicle performance was characterized by the mean task duration and mean error rates in performing in-vehicle operations. It was found that the mean task duration was the shortest in using the intuitive voice system with cluster display and drivers made more errors when using the traditional voice system relative to intuitive voice systems. The error rates were the lowest when using intuitive voice system with cluster display. The visual distraction effects were examined in terms of glance percentage to the windscreen (road ahead) and number of glances towards the central display and the cluster display. Reductions in glance percentage to the windscreen were observed when using intuitive voice interfaces, accompanied by increases in glance percentage to the prompt display. The primary driving performance in using the three voice-activation interfaces was not significantly affected compared with baseline car following only situation. It is concluded that intuitive voice interfaces are a viable enhancement to traditional voice interface whilst intuitive voice interface with cluster display has relative advantages of good task performance and minor visual distraction.

Both planned and unplanned events can reduce the capacities on roadways and result in congestion and delay. Currently, there are no complete and reliable sources which can be used by traffic operators to estimate capacity reductions. On many occasions, operators have to estimate capacity reductions using a large degree of subjectivity. This paper describes a methodology developed to validate capacity reductions from data collected within the traffic monitoring system. Methods for the determination of normal capacity, short-term and long-term capacity reductions are introduced. The proposed method has been successfully applied to derive capacity reductions using operational data. The results obtained are encouraging. It is believed that the method could be implemented in many traffic control centres to improve capacity reduction estimations

Collision warning systems work on the information provided by different sensors. Among many factors that can affect the performance of collision warning systems, the effect of sensor errors is investigated. Errors in direct measurements and derivatives are analysed based on typical sensor configurations of collision warning systems, which include a laser speedometer, a Radar/Lidar. Empirical sensor outputs under real traffic situations are used in deriving distributions of measurement errors. The uncertainties of collision warning criteria are then examined based on empirically derived sensor errors for three collision warning algorithms, the Honda, Mazda and NHTSA algorithm. It is found that under some problematic traffic situations and for certain algorithms, the sensor errors could significantly affect the performance of collision warning systems.

A methodology to estimate overall travel time from individual travel time measurements within a time window is presented. To better handle data with complex outlier generation mechanisms, fuzzy clustering techniques have been used to represent relationships between individual travel time data collected within a measuring time window. The data set is considered to be a fuzzy set to which each data point belongs at some degrees of membership. This allows transitions from the main body of data to extreme data points to be treated in a smooth and fuzzy fashion. Two algorithms have been developed based on ‘point’ and ‘line’ fuzzy cluster prototypes. Iterative procedures have been developed to calculate the fuzzy cluster centre and the fuzzy line. A novel estimation method based on time projection of a fuzzy line has been proposed. The method has the advantage of being robust by using a wide time window and the timeliness by employing time projection in resolving the most recent travel time estimation. Unlike deterministic approaches where hard thresholds need to be specified in order to exclude outliers, the proposed methods estimate travel times using all available data and, thus, can be applied in a wide variety of scenarios without fine tuning of the threshold.