Assessment of Pelagic Food Webs in Mendums Pond, NH

This study focused on the relationship between plankton in Mendums Pond, NH. A grazing experiment was conducted to determine the effect of zooplankton on the phytoplankton population. The phytoplankton were largely composed of net plankton (75 %) and this fraction was dominated by cyanobacteria (84.5 %) even though this was a slightly acidic system. Data indicated that the mean body length of zooplankton increased with depth. The average body length of Daphnia ranged from 1.4 mm in the epilimnion to 1.9 mm in the hypolimnion. Copepods followed a similar trend increasing in average body length from 0.85 mm to 0.95 mm. The high numbers of cyanobacteria and copepods resulted in a 17.92 % day-1 grazing rate indicating that almost 18 % of the total lake water was filtered every day by the zooplankton. This also suggests that the phytoplankton are reproducing at a higher rate than they are being consumed by grazers. This may raise concerns about the future diversity of the food web as cyanobacteria reproduce and become more dominant in this system

Suspension Testing of 3 Heavy Vehicles - Methodology and Preliminary Frequency Analysis

Three air-sprung heavy vehicles (HVs) were instrumented and tested on typical suburban and highway road sections at typical operational speeds. The vehicles used were a tri-axle semi-trailer towed with a prime mover, an interstate coach with 3 axles and a school bus with 2 axles. The air springs (air bags) of the axle/axle group of interest were configured such that they could be connected using either standard longitudinal air lines or an innovative suspension system comprising larger-than-standard longitudinal air lines. Data for dynamic forces on axles, wheels and chassis were gathered for the purposes of: analysis of the relative performance of the HVs for the two sizes of air lines; informing the QUT/Main Roads project Heavy vehicle suspensions – testing and analysis; and providing a reference source for future projects. This reports sets down the methodology and preliminary results of the testing carried out. Accordingly, Fast-Fourier plots are provided to show indicative frequency spectra for HV axles, wheel forces and air springs during typical use. The results are documented in Appendices 3 to 5. There appears to be little or no correlation between dynamic forces in the air springs and the wheel forces in the HVs tested. Axle-hop at frequencies between 10-15 Hz predominated for unsprung masses in the HV suspensions tested. Air-spring forces are present in the sub-1.0 Hz to approximately 2 Hz frequency range. With the qualification that only one set of data from each test speed is presented herein, in general, the peaks in the frequency spectra of the body-bounce forces and wheel forces were reduced for the tests with the larger longitudinal air lines. More research needs to be done on the load sharing mechanisms between axles on air-sprung HVs. In particular, how and whether improved load sharing can be effected and whether better load sharing between axles will reduce dynamic wheel and chassis forces. This last point, in particular, in relation to the varied dynamic measures used by the HV testing community to compare different suspension types

Time Series Analysis of Pavement Roughness Condition Data for use in Asset Management

Roughness is a direct measure of the unevenness of a longitudinal section of road pavement. Increased roughness corresponds to decreased ride comfort and increased road user costs. Roughness is relatively inexpensive to measure. Measuring roughness progression over time enables pavement deterioration, which is the result of a complex and chaotic system of environmental and road management influences, to be monitored. This in turn enables the long term functional behaviour of a pavement network to be understood and managed. A range of approaches has been used to model roughness progression for assistance in pavement asset management. The type of modelling able to be undertaken by road agencies depends upon the frequency and extent of data collection, which are consequences of funding available. The aims of this study are to increase the understanding of unbound granular pavement performance by investigating roughness progression, and to model roughness progression to improve roughness prediction methods. The pavement management system in place within the project partner road agency and the data available to this study lend themselves to a methodology allowing roughness progression to be investigated using financial maintenance and physical condition information available for each 1km pavement segment in a 16,000km road network

Modelling multimodal passenger choices with stated preference data

Redland Shire Council has recently started the implementation of an Integrated Local Transport Plan (ILTP) that aims to reduce the car dependency by enhancing the usage of alternative modes of transport. A multi mode choice model is required that can forecast the travel behaviour across the region in order to achieve the targets set in ILTP. This paper presents the findings of a state-of-the-art literature review done on mode choice modelling and outlines the development and calibration of a model to investigate the travel behaviour of Redlands’ residents. The present study attempts to develop a nested logit model and calibrate it using data obtained from a stated preference (SP) survey to be conducted in the Shire. The model development will consider all the vital attributes of the travelling modes used in the study area including various public transit access modes. The possibility of combining SP and revealed preference (RP) data to calibrate the model using joint-estimation method will be further assessed. It is expected that the outcomes of the research will assist policy makers in the areas of public transport planning and the development of network for public transport access modes including walkways and cycleways

Problems and prospects of non-motorized public transport integration in developing cities

The benefits and costs of the paid category of non-motorized public transport (NMPT) –especially three wheeler cycle rickshaws – have long been a major transport planning problem in many developing cities. Policy measures to restrict or eliminate non-motorized vehicles, especially NMPTs, from urban arterials and other feeder networks have already been implemented in developing cities as diverse as Delhi, Bangkok, Jakarta, Manila, Surabaya, Beijing and Bogotá. Over the last few years, the government of Bangladesh has implemented policies to phase out non-motorized transport, particularly rickshaws, from the major traffic spines of Dhaka City. The acceptability, rationality and implication of such ‘solutions’ are widely argued in Bangladesh, as well as internationally. The argument is severe in Dhaka, the case study of this research, considering social acceptability, economic response, fuel free eco-friendly characteristics and magnitude of role of rickshaw in sustaining the traffic and mobility needs of citizens. Therefore, rather than simply pursuing policies to eliminate NMPT, a better approach may be to integrate motorized and non-motorized vehicles as complementary rather than competitive forces in meeting the comprehensive demand of Dhaka’s transport. With the backdrop and given the international significance of the problem, this paper will delineate a preliminary framework for the future place of the NMPT-rickshaw and explore the problems as well as opportunities for its sustainable co-existence in a mixed mode transport stream that best meets the network performance needs of Dhaka

Investigation to enhance sustainable improvements in high speed rail transport

Transport systems are essential for the life of modern societies and economies. A sustainable transport system can shape a sustainable development pattern and socio-economic attributes of urban centres and regions. The use of private cars and trucks is increasing in most countries, creating more congestion, accidents, pollution and energy consumption. Many governments desire to achieve growth in public transport to overcome these adverse trends. A massive shift toward an environmentally sound type of transport is crucial and railways are deemed to be one of the most sustainable modes. All over the world the railway industry is involved in a renewal to reform and up-date rail, prompted largely by environmental concerns. The trend is to develop speed-competitive systems to expand transportation capacity. The focus of the current research, which is at its commencing stages, is to investigate the opportunities to apply an alternative approach to railway operations to overcome the difficulty of high speed transport in servicing larger amounts of demand, while achieving minimum point to point travel time, in a viable and integrated environment for both passenger and freight services. The expected outcome of the research project is to present a framework that may be used to identify and evaluate the most cost-effective transport solution to service not only major cities, but also regional centres along an interregional rail corridor, thus providing greater benefits on local economies and to build a spine for future development

AITPM Email Newsletter Volume 0911, November 2009: Presidents Message

President’s Report Hello fellow AITPM members, It is interesting to follow the news at present, where transport costs are getting a significant airing. Treasury Secretary Dr Ken Henry has enunciated something Australians may have considered extremely radical just a few years back, but in the present time appears to quite a few to be a realistic alternative. That being a rethink of the way we are charged for using our vehicles. It appears that serious consideration is being given to congestion charging, perhaps in place at least to some extent, of fuel excise. As a transport professional I am pleased that the debate has elevated to the national level, and would look forward that AITPM might contribute appropriately to it. As a motorist though, I naturally have my concerns about being hit in the hip pocket. Not that I actually drive during congested periods very much. I am fortunate to live five minutes either side of two well serviced bus corridors, one of which will eventually become a busway, and work in the central business district, which is hub from all spokes in Brisbane. As such, bus and foot are my preferred commute modes. Ah but I should not gloat, as my smart card fare is about to increase by 20 percent in the New Year! And if the newspapers are to be believed, further substantial increments are proposed over the coming few years. This is reported to recoup some more of the costs of actually providing the quality public transport system that we enjoy in our region. So I expect it will be very interesting to see how transport economics will play out in reality in the coming few years, and how governments cater to Australians who either cannot afford substantial increases in transport costs or have no viable alternatives to those facilities whose costs will increase. The 2010 AITPM National Conference, “What’s New?”, still has the opportunity for authors to submit an abstract for consideration so please consider how you might contribute to the event. Best regards to all, Jon Bunke

How Should We Prioritise Incident Management Deployment?

With perpetual strains on resources and traffic increasing at a steady rate, transport agencies need to evaluate the road network and make informed decisions to determine which roads have the greatest risk of adverse impacts and therefore identify the roads that have the greatest case for intervention. This is especially the case for Intelligent Transport Systems (ITS) and in particular incident management services where decision-making techniques are immature relative to conventional road engineering. This problem is compounded by the fact that common evaluation tools are insufficient for ITS applications. Historical information for ITS impacts is not always readily available, impacts are not transferable and impacts are incremental to the individual user. For these reasons, a new network evaluation framework is presented in this paper for incident management deployment. The framework aims to analyse the road network and prioritise roads with respect to two factors: the historical risk associated with incidents; and the cost effectiveness of implementation. To assess the historical risk, the framework initially converts social, economic and environmental impacts to a common monetary base, enabling the addition of the incident impacts. The economic impact values must be treated as relative values of measurement, not absolute costs. The second part of the framework assesses the historical risk, taking into account both the consequence of an event, measured in economic terms described above, and the probability of an event occurring based on historical information. The third uses a cost-effective ratio comparing the reduced impacts with the project costs. The economic risk analysis presented in Figure 1 below integrates safety, reliability and environmental impacts, providing an integrated decision-making tool for proactive ITS deployment decision-making

Investigation into Travel Modes for Transit Oriented Development: Employees' Travel Survey of Kelvin Grove Urban Village

Travel surveys were conducted for collecting data related to visitors travel to Kelvin Grove Urban Village (KGUV). KGUV has employees of retail shopping centre, employees of educational land use, school and university students and shoppers as visitors of this area. As a part of data collection process a travel surveys was undertaken for employees and students of KGUV. This document contains the questionnaire form used to collect the data related to employee travel. Similar questions were asked to the students of KGUV. The instructions given for filling out the survey were not included in the actual questionnaire form as internet based surveys were undertaken. This form was used for personal interviews and Computer Assisted Personal Interview (CAPI) surveys undertaken for employees of the retail shopping centre

Identifying relationship between skid resistance and road crashes using probability-based approach

Road accidents are of great concerns for road and transport departments around world, which cause tremendous loss and dangers for public. Reducing accident rates and crash severity are imperative goals that governments, road and transport authorities, and researchers are aimed to achieve. In Australia, road crash trauma costs the nation A$15 billion annually. Five people are killed, and 550 are injured every day. Each fatality costs the taxpayer A$1.7 million. Serious injury cases can cost the taxpayer many times the cost of a fatality. Crashes are in general uncontrolled events and are dependent on a number of interrelated factors such as driver behaviour, traffic conditions, travel speed, road geometry and condition, and vehicle characteristics (e.g. tyre type pressure and condition, and suspension type and condition). Skid resistance is considered one of the most important surface characteristics as it has a direct impact on traffic safety. Attempts have been made worldwide to study the relationship between skid resistance and road crashes. Most of these studies used the statistical regression and correlation methods in analysing the relationships between skid resistance and road crashes. The outcomes from these studies provided mix results and not conclusive. The objective of this paper is to present a probability-based method of an ongoing study in identifying the relationship between skid resistance and road crashes. Historical skid resistance and crash data of a road network located in the tropical east coast of Queensland were analysed using the probability-based method. Analysis methodology and results of the relationships between skid resistance, road characteristics and crashes are presented