Spelling suggestions: "subject:"[een] TRAFFIC"" "subject:"[enn] TRAFFIC""
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Computer simulation of marine traffic systemsColley, B. A. January 1985 (has links)
A computer model was constructed that allowed two vessels involved in a possible collision situation to take collision avoidance action following the "International Regulations for Preventing Collisions at Sea". The mariners’ actions were modelled by the concepts of the domain and the RDRR (Range to Domain/Range-rate). The domain was used to determine if a vessel was threatening and the RDRR to determine the time at which a vessel should give-way to a threatening target. Each vessel in the simulation had four domains corresponding to the type of encounter in which the vessel was involved. Values for the time at which a vessel manoeuvres and the domain radii were determined from an analysis of high quality cine films of the radar at H.M. Coastguard at St. Margaret's Bay, Dover. Information was also taken from simulator exercises set up on the Polytechnic radar simulator. The two ship encounter was then developed to become the multi-ship encounter and eventually was able to model over 400 vessels over a two day period through a computer representation of the Dover Strait. A further development included a computer graphical representation of a radar simulator running in real-time, and which allowed a mariner to navigate one of the vessels using computer control. A validation of the computer model was undertaken by comparing the simulated results with those observed from the cine films. Following the validation several examples of the computer model being used as a decision support system were included.
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An examination of relationships between road accidents and traffic flowMcGuigan, David Ronald Dickson January 1987 (has links)
In this thesis it is suggested that the cost-effectiveness of road safety expenditure on low cost engineering remedial works could be improved because the currently adopted methods for assessing expenditure priorities do not necessarily identify thosa sites at which the greatest potential for accident reduction exists. An alternative method for the generation of more cost-effective programmes of works is proposed and justified. This method adopts the rationale of identifying those sites at which accidents are occurring in higher numbers than would otherwise be expected for such sites with equivalent traffic volumes and locations. The justification for the method involves detailed statistical analyses of over 10,000 accidents occurring in Lothian Region for the years 1979-1982 which demonstrate that there are significant relationships between accidents and traffic volumes and location details (eg junction type, form of junction control, adjacent roadside development and carriageway type). On this basis, models for accident occurrence have been determined. The analyses show that the temporal distribution conforms with a Poisson process and that the spatial distribution is negative binomial. It is shown - for both links and junctions - that whilst there are significant differences between the models for different accident types, they do not, in aggregate, produce significantly better models for all accidents than simple all accident models. In addition, the importance of regression-to-mean has been established as an effect which should be accounted for not just at the monitoring stage of completed schemes but as an integral part of the initial site selection process. Finally, it is demonstrated that the proposed method, which is called Potential Accident Reduction (PAR), may provide an improvernent of cost-effectiveness of road safety expenditure of up to 25% over the currently adopted methods.
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An investigation of noise produced by unsteady gas flow through silencer elementsMawhinney, Graeme Hugh January 1999 (has links)
No description available.
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Performance study of incident modelling on southern expressway using PARAMICS micro simulation software /Patel, Narendra. Unknown Date (has links)
The purpose of the study is to use micro simulation as an evaluation tool to evaluate the performance efficiency of the Southern Expressway. This thesis work demonstrates the potential benefits of using microscopic simulation models when developing incident response and clearance strategies. The project findings, however, are expected to assist transportation officials and Government agencies in developing effective traffic management strategies in the event of non recurrent or incident. This thesis work also offers them a tool to evaluate the impact of any type of incident on transportation network operations. / In order to ensure that the transportation system is ready to support rapid and effective response to any kind of incident, facilitate the movement of people and goods even in times of congestion crisis, and capable to quickly restore services to full capacity and also to manage an incident effectively, it is necessary to calculate and estimate the incidents impact on traffic network. Basic analysis techniques widely used to estimate the loss of capacity due to incident are average speed, queue length etc. and these measures can be used further to support the formulation of a response plan i.e. route diversion etc. An important element of an effective incident management program is the ability to accurately estimate the freeway capacity remaining following an incident. In this thesis we used PARAMICS V 5.1 to model the Southern Expressway network, Adelaide during evening peak (17:30:00 pm) southbound traffic to measure the efficiency of the Southern Expressway in incident scenario. The PARAMICS V 5.1 name is a short form derived form PARAllel computer MICropic Simulation. The PARAMICS V 5.1 is a unique microscopic urban and freeway traffic simulation software package for modelling of movement and behaviour of individual vehicle on a road network and widely used for ITS modelling. / The traffic results determined after comparing 0, 15, 30 and 60 minutes incident duration with alteration of 1 lane lockage, 2 lane blockage scenario as well as 15 minutes blockage of all 3 lanes scenario. All Scenarios give the performance of Southern Expressway as well as to estimate the Southern Expressway capacity remaining following an incident. From the detectors network is able to count the total number of vehicles passing through that lane. Final result and calculated difference of each scenario can tell us the percentage diversion rate due to vehicles incident on Southern Expressway. Dynamic feedback assignment is re-routing every 5 minutes and gives direction to vehicles on less congestion routes. These diverted rates to other arterial roads are useful for further support of formulation of a response plan. To evaluate the performance of Southern Expressway network, measures of effectiveness (MOEs), such as average speed, queue length and delay in seconds as well as VHT (Vehicle Hour Travel) value of whole network considered and compared with Base condition or Non- Incident or 0 minute incident duration. The impact of incidents was found to vary with number of blocked lanes and incident duration. / From the results we can clearly observe that by using Dynamic feedback assignment we achieved up to 16 % diversion from Southern Expressway to Main South road. Average speed was 12 km/h during 2 lanes blockage scenario and reaches 91 pcus/lane/km queue length. Highest delay recorded for 155 seconds during 2 lanes blockage scenario and 45 minutes incident duration. 2 lanes blockage scenario has highest value of total Vehicle Hour Travel (VHT). / The final results of this research are important for planning capacity enhancing expressway improvements. As we know duration of incident and lanes blockage conditions are able to serve and uncover the strengths and weaknesses of current crash management and provide important directions for traffic management system improvements. / Thesis (MEng(TransportSystemsEng))--University of South Australia, 2006.
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The impact of bicycle lanes on critical gaps at unsignalised T-junctions /Wilson, Ben. Unknown Date (has links)
There is a significant gap in the current understanding of issues relating to bicycle safety. The provision of cycling facilities has long been based on professional opinion and has rarely been based on academic research. In particular, it is widely considered that the provision of bicycle lanes improves safety for cyclists, however there is little or no research to confirm this belief. / This thesis seeks to improve the current understanding of the impact of bicycle lanes on safety by utilising gap acceptance theory. Unsignalised T-junctions have been surveyed to gather gap data for the estimation and comparison of critical gaps. The findings of this research indicate that bicycle lanes may in fact reduce safety at unsignalised intersections. / Thesis (MEng(TransportSystemsEng))--University of South Australia, 2006.
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Accident investigation and local area traffic management scheme evaluationXu, Min January 1999 (has links)
Thesis (MEng)--University of South Australia, 1999
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Accident investigation and local area traffic management scheme evaluationXu, Min January 1999 (has links)
Thesis (MEng)--University of South Australia, 1999
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Accident investigation and local area traffic management scheme evaluationXu, Min January 1999 (has links)
Thesis (MEng)--University of South Australia, 1999
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Anatomy of a traffic disaster : towards a sustainable solution to Bangkok's transport problemsadt@murdoch.edu.au, Chamlong Poboon January 1997 (has links)
Bangkok's extreme traffic problems have been traditionally explained in terms of a lack
of road infrastructure and policy responses for many years have almost exclusively
stressed road investment to the exclusion of all other forms of transport infrastructure
development. This thesis questions this interpretation of the traffic problem and its
chief policy response: building still more roads. It suggests that in order to effectively
analyse Bangkok's traffic predicament and to formulate more sustainable responses to
the crisis, an understanding is required of Bangkok's land use and transport
development, as well as a systematic and detailed perspective on the similarities and
differences between Bangkok and many other cities around the world, particularly
those in Asia.
This thesis suggests that Bangkok has passed through three key periods: a water-based
transport and walking period, a transport modernisation period and a motorisation
period. In each period up to motorisation Bangkok appeared to maintain a harmonious
relationship between its high density, mixed use urban form, ideally suited to nonmotorised
modes and to public transport. Even in the motorisation period, high
density, mixed use development has mostly followed major road corridors and
remains well-suited to much higher public transport and non-motorised mode use than
currently exist. However, in this period, rapidly rising motor vehicle ownership and use
began to come into conflict with the city's pre-automobile form. Road infrastructure
could not be built fast enough to keep pace with traffic growth, despite almost
exclusive commitment of resources to roads. High capacity public transport systems,
including rail, renewed water transport and busways failed to materialise to help curb
the motorisation process and to provide much needed relief on the roads. A basic
conflict or mismatch between urban form and transport began to emerge, leaving the
city ill-equipped to cope with the automobile and subject to large environmental, social
and economic impacts from congestion.
The thesis argues that while Bangkok's per capita road supply is low in an
international sense, it is not atypical for an Asian city and road availability per hectare
is similar to many other cities around the world. Likewise, common arguments about
an inadequate road hierarchy are systematically analysed and are shown to be
insufficient in explaining Bangkok's present crisis. The thesis thus suggests that
attempting to tackle the traffic problem through an intensification of road building
efforts will not provide the relief sought, but will only exacerbate the traffic impacts
which are shown to be already at the limits of international experience.
The international comparison of Bangkok with other cities, highlighting basic
similarities and differences in land use and transport features, continues to build upon
this argument. It shows that Bangkok lies at one extreme in many transport
characteristics such as the amount of travel per hectare, and within the Asian cities, it
is very high in vehicle ownership and use and energy use, comparatively low in public
transport use and very low in non-motorised modes. The thesis suggests that in
physical planning terms, Bangkok's traffic crisis appears to stem from a set of
mismatches between its transport patterns, urban form and transport infrastructure.
These mismatches are between: (1) vehicle use and urban form: higher levels of private
vehicle use than can be properly accommodated in its dense, tightly woven urban
fabric; (2) vehicle use and road supply: levels of private vehicle use which are
incompatible with its road availability and which are uncharacteristically high
compared to other Asian cities; (3) transit use, urban form and road supply: lower
levels of overall transit use than would be expected in a city of its urban form and road
availability; (4) transit infrastructure, urban form and road supply: a public transport
infrastructure which is inadequate to meet the demands for transit movement inherent
in such a dense city, particularly a lack of rail infrastructure; (5) non-motorised modes
and urban form: levels of non-motorised mode use which are uncharacteristically low
for such a dense, mixed use urban fabric. These mismatches are mainly the consequence
of a long series of inappropriate and ineffective transport policies and investments
which are biased towards private transport and which have at least in part arisen
from narrow and outdated transport planning processes.
In order for transport planning in Bangkok to address the suggested roots of the crisis,
the thesis contends that at least two key constraints would have to be dealt with: the
traditional urban transport planning process and the institutional fragmentation in
transport policy and implementation. Notwithstanding, there are forces pushing in the
direction of change and these are examined in terms of the growing global and local
trends towards sustainability, community outrage over traffic and the role of NGOs.
Based on these findings, this thesis provides a case for a series of policies to help deal
with Bangkok's traffic disaster. In line with global trends towards sustainability as an
organising principle for urban policy development, these policies are offered within a
framework of developing a more sustainable transport system in Bangkok. The policies
suggested cover priority to public transport infrastructure development, transitoriented,
mixed land use development, transport demand management, improvement
of waterway transportation, facilitation of walking and cycling and institutional
reform of Bangkok's transport decision making structure. Opportunities for further
complementary research are suggested.
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The application of American highway standards to highways in Turkey /Lazarides, Orestes Paul. January 1952 (has links)
Thesis (M.S.)--Oregon State College, 1952. / Typescript. Includes bibliographical references (leaves 87-88). Also available via the World Wide Web.
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