Empirical modelling of the relationship between bus and car speeds on signalised urban networks

Vehicle speed is an important attribute for analysing the utility of a transport mode. The speed relationship between multiple modes of transport is of interest to traffic planners and operators. This paper quantifies the relationship between bus speed and average car speed by integrating Bluetooth data and transit signal priority data from the urban network in Brisbane, Australia. The method proposed in this paper is the first of its kind to relate bus speed and average car speed by integrating multi-source traffic data in a corridor-based method. Three transferable regression models relating not-in-service bus, in-service bus during peak periods and in-service bus during off-peak periods with average car speed are proposed. The models are cross-validated and the interrelationships are significant.     

A study of the effects of spatial contiguity and hierarchically structured headings in a shipboard operating and maintenance manual

The notion of operating and maintenance manuals being validated as fit for purpose is based largely on conjecture, as causal factors contributing to rule-based (procedure-based) human error at sea are under-theorised and under-researched. Human factors theories offer little in terms of framework as to the constitution of a bad rule. In this study, an original equipment manufacturer (OEM) operating and maintenance manual was assessed against two rule-based error-provoking markers identified through literature review. The contribution of the original and subsequently modified OEM operating and maintenance manuals towards both behaviour modification and rule-based error was assessed through a workshop-based study. Randomly selected seafaring participants were tasked with the responsibility of executing a typical shipboard operational procedure by referring to an original or modified version of the manual. The study supported the following hypotheses: (1) the hierarchical access structure of headings in an operating and maintenance manual supports the primary function of selection, and (2) the efficacy of inference in a procedure-based task is dependent upon the spatial contiguity of corresponding text and illustrations in an operating and maintenance manual. The findings of this study suggest that a nexus exists between the structure of operating and maintenance manuals, behaviour modification and human error. Furthermore, this study demonstrates a need for further research into specific causal factors contributing towards rule-based error in shipboard operating and maintenance tasks.     

气候变化与全球汽车排放法规

本文纵观美国、欧盟国家和亚洲关于汽车排放的法规制度,探究现有及未来政策对汽车工业产生的影响。     

Quantitative assessment of effect of enforcement intensity on violation rates of vehicle weight and dimension regulations

A theory of upper bound limit describing the relationship between maximum possible violation rate as a function of the intensity of enforcement of vehicle weight and dimension regulations and indeed other transport administrative regulations is postulated. The model is an exponential function that determines the maximum violation rate for given inspection capacity. The constant of the function depends on the method of enforcement. The theory is demonstrated to be valid. It has potential for facilitating important policy issues relating to enforcement of transport administrative regulations and within the framework of infrastructure management to be addressed.

The relative effectiveness of enforcement methods is quantified by two parameters namely, the effectiveness index and the truckers’ relative perceived probability of detection. These parameters facilitate evaluation of the performance of various enforcement methods and operation strategies. It is found that patrol teams are, on average, 30 times as effective in detecting violations as continuously operated permanent weigh scales. High perceived detection probabilities are associated with high inspection capacities. To increase the perceived detection probability (reduce violation rates) therefore implies increasing the inspection capacity.     

Characterization of incidents on an urban arterial road

The early warning of incidents on urban arterial roads in a congested city can reduce delay, accidents and pollutant emission. Freeway incident detection systems implemented in recent years may not be suitable for arterial incidents. Arterial incident detection is more difficult. The traffic flow on an arterial road is not conserved from the upstream end of a road link to the downstream end because urban traffic does turn in and out of side‐streets, car‐parks and local residences. Roadside friction such as kerbside parking and shopping traffic also tends to create apparent incidents which are in fact frequent and normal events. This paper develops a definition for an arterial incident and describes a case study on an arterial road in Melbourne, Australia. The study shows that detectors upstream of an incident are more useful for incident detection than downstream detectors. It also identifies occupancy and speed as the appropriate parameters to characterise and detect arterial incidents.     

Dependability as a measure of on-time performance of personal rapid transit systems

A comprehensive method for calculating and measuring Dependability of Personal Rapid Transit systems is derived and compared with the more common measure called Availability. Availability is the percentage of all revenue trips that are completed without interruption. It does not take into account the duration of delays of the passengers because of the diffiiculty of gathering the necessary information in conventional transit systems. In PRT systems, vehicle-hours of travel and of delay relate in a statistically simple way to person-hours of travel and of delay. Therefore, in such systems, it is practical to use the performance measure called Dependability that takes into account the inconveince of people as a result of delays. To form a bridge to present practice, it is recommended that both measures be calculated and compared in forthcoming PRT systems. With today's computer systems, this is easily accomplished.