Transit line passenger transmission and productiveness under high load conditions

Deterministic transit capacity analysis applies to planning, design and operational management of urban transit systems. The Transit Capacity and Quality of Service Manual (1) and Vuchic (2, 3) enable transit performance to be quantified and assessed using transit capacity and productive capacity. This paper further defines important productive performance measures of an individual transit service and transit line. Transit work (p-km) captures the transit task performed over distance. Passenger transmission (p-km/h) captures the passenger task delivered by service at speed. Transit productiveness (p-km/h) captures transit work performed over time. These measures are useful to operators in understanding their services’ or systems’ capabilities and passenger quality of service. This paper accounts for variability in utilized demand by passengers along a line and high passenger load conditions where passenger pass-up delay occurs. A hypothetical case study of an individual bus service’s operation demonstrates the usefulness of passenger transmission in comparing existing and growth scenarios. A hypothetical case study of a bus line’s operation during a peak hour window demonstrates the theory’s usefulness in examining the contribution of individual services to line productive performance. Scenarios may be assessed using this theory to benchmark or compare lines and segments, conditions, or consider improvements.

Opportunities of public transport experience enhancements with mobile services and urban screens

Public transportation is an environment with great potential for applying innovative ubiquitous computing services to enhance user experiences. This paper provides the underpinning rationale for research that will be looking at how real-time passenger information system deployed by transit authorities can provide a core platform to improve commuters’ user experiences during all stages of their journey. The proposal builds on this platform to inform the design and development of innovative social media, mobile computing and geospatial information applications, with the hope to create fun and meaningful experiences for passengers during their everyday travel. Furthermore, we present the findings of our pilot study that aims to offer a better understanding of passengers’ activities and social interactions during their daily commute.

The philosophy and practice of water sensitive urban design : is it consistent with a whole system approach

This paper provides a critique of the Water Sensitive Urban Design (WSUD) paradigm by discussing its congruence with an established sustainable design principle called 'whole system design'. It was found that WSUD is congruent with the whole system design approach as a philosophy, but not in practice. Future improvement of WSUD practice may depend on the adoption of a front-loaded, teamwork-based design and planning process that is embedded in the principle of whole system design.

Impact of embeddedness in ethnic networks on business growth : evidence from Chinese immigrant entrepreneurs in Australia

Immigrant entrepreneurship, or, self-employment by immigrants (Light & Bonacich, 1988), has been of growing interest to researchers (Hosler, 1996). This is due in part to major immigrant receiving countries, such as Australia, the United States, Canada, the United Kingdom and Western Europe, experiencing a high growth rate in their immigrant populations, leading to a more visible presence of immigrant business in major cities (Woon, 2008). By starting their own businesses, immigrant entrepreneurs may circumvent some of the barriers and disadvantages encountered in looking for a job (Sequeira & Rasheed, 2006). Successful immigrant entrepreneurs will integrate into the economy by creating jobs, providing products and services for members of their own ethnic community and society, as well as introducing new products and services that expand consumers’ choices (Rath & Kloosterman, 2000). Immigrant entrepreneurs tend to start business within their ethnic enclave, as it is an integral part of their social and cultural context and the location where ethnic resources reside (Logan et al., 2002). An ethnic enclave is an interdependent network of social and business relationships that are geographically concentrated with its co-ethnic people (Portes & Bach, 1985).

Program your city : designing an urban integrated open data API

Cities accumulate and distribute vast sets of digital information. Many decision-making and planning processes in councils, local governments and organisations are based on both real-time and historical data. Until recently, only a small, carefully selected subset of this information has been released to the public – usually for specific purposes (e.g. train timetables, release of planning application through websites to name just a few). This situation is however changing rapidly. Regulatory frameworks, such as the Freedom of Information Legislation in the US, the UK, the European Union and many other countries guarantee public access to data held by the state. One of the results of this legislation and changing attitudes towards open data has been the widespread release of public information as part of recent Government 2.0 initiatives. This includes the creation of public data catalogues such as data.gov.au (U.S.), data.gov.uk (U.K.), data.gov.au (Australia) at federal government levels, and datasf.org (San Francisco) and data.london.gov.uk (London) at municipal levels. The release of this data has opened up the possibility of a wide range of future applications and services which are now the subject of intensified research efforts. Previous research endeavours have explored the creation of specialised tools to aid decision-making by urban citizens, councils and other stakeholders (Calabrese, Kloeckl & Ratti, 2008; Paulos, Honicky & Hooker, 2009). While these initiatives represent an important step towards open data, they too often result in mere collections of data repositories. Proprietary database formats and the lack of an open application programming interface (API) limit the full potential achievable by allowing these data sets to be cross-queried. Our research, presented in this paper, looks beyond the pure release of data. It is concerned with three essential questions: First, how can data from different sources be integrated into a consistent framework and made accessible? Second, how can ordinary citizens be supported in easily composing data from different sources in order to address their specific problems? Third, what are interfaces that make it easy for citizens to interact with data in an urban environment? How can data be accessed and collected?

Measuring urban form : a comparative analysis of South East Queensland and South Florida

At first glance the built environments of South Florida and South East Queensland appear very similar, particularly along the highly urbanized coast. However this apparent similarity belies some fundamental differences between the two regions in terms of context and the approach to regulating development. This paper describes some of these key differences, but focuses on two research questions: 1) do these differences affect the built environment; and 2) if so, how does the built form differ? There has been considerable research on how to best measure urban form, particularly as it relates to measuring urban sprawl (Schwarz 2010; Clifton et al. 2008). Some of the key questions identified by this research include: what are the best variables to use?; what scale should be used?; and what time period to use? We will assimilate this research in order to develop a methodology for measuring urban form and apply it to both case study regions. There are several potential outcomes from this research -- one is that the built form between the two regions is quite different; and the second is that it is similar. The first outcome is what might be expected given the differences in context and development regulation. However how might the second outcome be explained – major differences in context and development regulation resulting in minor differences in key measures of urban form? One explanation is that differences in the way development is regulated are not as important in determining the built form as are private market forces.

Prediction of the wash-off of traffic related semi- and non-volatile organic compounds from urban roads under climate change influenced rainfall characteristics

Traffic generated semi and non volatile organic compounds (SVOCs and NVOCs) pose a serious threat to human and ecosystem health when washed off into receiving water bodies by stormwater. Climate change influenced rainfall characteristics makes the estimation of these pollutants in stormwater quite complex. The research study discussed in the paper developed a prediction framework for such pollutants under the dynamic influence of climate change on rainfall characteristics. It was established through principal component analysis (PCA) that the intensity and durations of low to moderate rain events induced by climate change mainly affect the wash-off of SVOCs and NVOCs from urban roads. The study outcomes were able to overcome the limitations of stringent laboratory preparation of calibration matrices by extracting uncorrelated underlying factors in the data matrices through systematic application of PCA and factor analysis (FA). Based on the initial findings from PCA and FA, the framework incorporated orthogonal rotatable central composite experimental design to set up calibration matrices and partial least square regression to identify significant variables in predicting the target SVOCs and NVOCs in four particulate fractions ranging from >300-1 μm and one dissolved fraction of <1 μm. For the particulate fractions range >300-1 μm, similar distributions of predicted and observed concentrations of the target compounds from minimum to 75th percentile were achieved. The inter-event coefficient of variations for particulate fractions of >300-1 μm were 5% to 25%. The limited solubility of the target compounds in stormwater restricted the predictive capacity of the proposed method for the dissolved fraction of <1 μm.

Controlled growth of carbon nanotubes for electronic and photovoltaic applications

Carbon nanotubes (CNTs), experimentally observed for the first time twenty years ago, have triggered an unprecedented research effort, on the account of their astonishing structural, mechanical and electronic properties. Unfortunately, the current inability in predicting the CNTs’ properties and the difficulty in controlling their position on a substrate are often limiting factors for the application of this material in actual devices. This research aims at the creation of specific methodologies for controlled synthesis of CNTs, leading to effectively employ them in various fields of electronics, e.g. photovoltaics. Focused Ion Beam (FIB) patterning of Si surfaces is here proposed as a means for ordering the assembly of vertical-aligned CNTs. With this technique, substrates with specific nano-structured morphologies have been prepared, enabling a high degree of control over CNTs’ position and size. On these nano-structured substrates, the growth of CNTs has been realized by chemical vapor deposition (CVD), i.e. thermal decomposition of hydrocarbon gases over a heated catalyst. The most common materials used as catalysts in CVD are transition metals like Fe and Ni; however, their presence in the CNT products often results in shortcomings for electronic applications, especially for those based on silicon, being the metallic impurities incompatible with very-large-scale integration (VLSI) technology. In the present work the role of Ge dots as an alternative catalysts for CNTs synthesis on Si substrates has been thoroughly assessed, finding a close connection between the catalytic activity of such material and the CVD conditions, which can affect both size and morphology of the dots. Successful CNT growths from Ge dots have been obtained by CVD at temperatures ranging from 750 to 1000°C, with mixtures of acetylene and hydrogen in an argon carrier gas. The morphology of the Si surface is observed to play a crucial role for the outcome of the CNT synthesis: natural (i.e. chemical etching) and artificial (i.e. FIB patterning, nanoindentation) means of altering this morphology in a controlled way have been then explored to optimize the CNTs yield. All the knowledge acquired in this study has been finally applied to synthesize CNTs on transparent conductive electrodes (indium-tin oxide, ITO, coated glasses), for the creation of a new class of anodes for organic photovoltaics. An accurate procedure has been established which guarantees a controlled inclusion of CNTs on ITO films, preserving their optical and electrical properties. By using this set of conditions, a CNTenhanced electrode has been built, contributing to improve the power conversion efficiency of polymeric solar cells.

A continuum model of the growth of engineered epidermal skin substitutes

We present a porous medium model of the growth and deterioration of the viable sublayers of an epidermal skin substitute. It consists of five species: cells, intracellular and extracellular calcium, tight junctions, and a hypothesised signal chemical emanating from the stratum corneum. The model is solved numerically in Matlab using a finite difference scheme. Steady state calcium distributions are predicted that agree well with the experimental data. Our model also demonstrates epidermal skin substitute deterioration if the calcium diffusion coefficient is reduced compared to reported values in the literature.

Driver response time of queuing vehicles at urban signalized intersections

Driver response (reaction) time (tr) of the second queuing vehicle is generally longer than other vehicles at signalized intersections. Though this phenomenon was revealed in 1972, the above factor is still ignored in conventional departure models. This paper highlights the need for quantitative measurements and analysis of queuing vehicle performance in spontaneous discharge pattern because it can improve microsimulation. Video recording from major cities in Australia plus twenty two sets of vehicle trajectories extracted from the Next Generation Simulation (NGSIM) Peachtree Street Dataset have been analyzed to better understand queuing vehicle performance in the discharge process. Findings from this research will alleviate driver response time and also can be used for the calibration of the microscopic traffic simulation model.

Role of solids in heavy metals build-up on urban road surfaces

Solids are widely identified as a carrier of harmful pollutants in stormwater runoff exerting a significant risk to receiving waters. This paper outlines the findings of an in-depth investigation on heavy metal adsorption to solids surfaces. Pollutant build-up samples collected from sixteen road sites in residential, industrial and commercial land uses were separated into four particle size ranges and analysed for a range of physico-chemical parameters and nine heavy metals including Iron (Fe), Aluminum (Al), Lead (Pb), Zinc (Zn), Cadmium (Cd), Chromium (Cr), Manganese (Mn), Nickel (Ni) and Copper (Cu). High specific surface area (SSA) and total organic carbon (TOC) content in finer particle size ranges was noted, thus confirming strong correlations with heavy metals. Based on their physico-chemical characteristics, two different types of solids originating from traffic and soil sources were identified. Solids generated by traffic were associated with high loads of heavy metals such as Cd and Cr with strong correlation with SSA. This suggested the existence of surface dependent bonds such as cation exchange between heavy metals and solids. In contrast, Fe, Al and Mn which can be attributed to soil inputs showed strong correlation with TOC suggesting strong bonds such as chemsorption. Zn was found to be primarily attached to solids by bonding with the oxides of Fe, Al and Mn. The data analysis also confirmed the predominance of the finer fraction, with 70% of the solids being finer than 150 µm and containing 60% of the heavy metal pollutant load.

Benefits and issues of urban network travel time prediction

This paper presents the benefits and issues related to travel time prediction on urban network. Travel time information quantifies congestion and is perhaps the most important network performance measure. Travel time prediction has been an active area of research for the last five decades. The activities related to ITS have increased the attention of researchers for better and accurate real-time prediction of travel time. Majority of the literature on travel time prediction is applicable to freeways where, under non-incident conditions, traffic flow is not affected by external factors such as traffic control signals and opposing traffic flows. On urban environment the problem is more complicated due to conflicting areas (intersections), mid-link sources and sinks etc. and needs to be addressed.

Imagining the city : using fiction to explore urban environments

The paper will describe the ongoing project, Imagining the City: Brisbane Short Story Competition. In 2010, as part of a study investigating urban planning and the gentrification of inner city landmarks, QUT researchers developed six personas to help inform the design of city apartments. Rather than view these personas as static, the authors solicited creative responses to promote further development. Submissions of short stories based on one of the persons, and set in Brisbane, were invited from the general public. Successful stories will be published in an online anthology and as an iPhone application. The paper draws on ethnographic fiction theory to answer the question, how can research, specifically persona and use scenario, be transformed into fiction? The authors suggest that such creative responses in the form of fiction may be useful for urban designers.

An exploratory study of the factors enhancing and inhibiting export growth in the Chilean wine industry

The objective of this exploratory study is to investigate the main drivers that enhance and inhibit the export performance of Chilean wineries. Based on survey data collected from Chilean wineries, the findings of this study suggest that the main constraints within the Chilean wineries in developing exports is the lack of financial resources, limited quantities of stocks for market expansion, management’s lack of knowledge and experience, and the high cost of travelling and participating in trade shows. The main drivers of wine export performance according to the respondents are high quality of the wines, well established network of international distributors, and marketing skills. The major inhibitors of developing wine exports are exchange rate variability, problems in selecting a reliable international distributor, and limited government support to promote wine exports. This study also shows that export managers of Chilean wineries have high educational levels and have international experience. The findings have important implications for export development efforts of both governments and managers.

ACE research vignette 008 : acquisitions - a route to new growth opportunities?

This series of research vignettes is aimed at sharing current and interesting research findings from our team and other international Entrepreneurship researchers. In this vignette, Professor Per Davidsson considers some of the dynamics associated with firm growth.