Physical Sciences and Mathematics Commons^™

Conclusion: Tackling The 'Missing Scale' In Environmental Policy, Ruth Lane, Andrew W. Gorman-Murray

Faculty of Science - Papers (Archive)

The foregoing chapters have demonstrated that household sustainability is a complex issue that requires thoughtful discussion from multiple perspectives. Indeed throughout this collection we have encouraged a dialogical approach. On the one hand our aim has been to bring researchers from human geography and cultural studies into a productive dialogue around the material geographies of household sustainability. There has been enthusiastic cross-fertilisation of ideas and approaches shown through the chapters, which critically develop the interconnections between the material, socia-technical, culturaJ, embodied and political dimensions which make households function, with particular attention to how they (might) function in environmentally sustainable ways. …

Remote Sensing Of Atmospheric Trace Gases By Ground-Based Solar Fourier Transform Infrared Spectroscopy, Clare Paton-Walsh

Faculty of Science - Papers (Archive)

The changing composition of the earth’s atmosphere is a matter of intense scientific research as we strive to understand details of the physical and chemical mechanisms that control our climate. Fourier transform spectroscopy has been applied very successfully to the study of trace gases in the atmosphere by examining terrestrial atmospheric absorption lines in the infrared spectrum from the Sun. In fact many gases were first discovered in the atmosphere during the 1940’s from their absorption features in the infrared solar spectrum. These early optical absorption measurements of the atmosphere using the Sun as a source were made with grating …

Electronic Interactions Within Composites Of Polyanilines Formed Under Acidic And Alkaline Conditions. Conductivity, Esr, Raman, Uv-Vis And Fluorescence Studies, L Dennany, P C. Innis, S T. Mcgovern, Gordon G. Wallace, Robert J. Forster

Faculty of Science - Papers (Archive)

The properties of two forms of polyaniline (PAni) synthesised under acidic and basic conditions have been investigated both individually and as combined complexes. The PAni polymerised within alkaline media was redox inactive and non-conducting while the PAni emeraldine salt (ES) was electroactive and conducting. Raman, electron spin resonance, UV-Vis and fluorescence spectroscopies were used to monitor the changes in electronic properties of these conducting polymer composites. Solution cast films of alkaline synthesised (A-PAni) with the PAni ES resulted in an increase in the high spin polaron population suggesting that it acts as a pseudodopant. The ability of the A-PAni to …

Influence Of Salicylic Acid On Alkaloid Production By Root Cultures Of Stemona Curtisii Hook. F., K. Chotikadachanarong, S. Dheeranupattana, Chaiwat Jatisatienr, S. Wangkarn, Pitchaya Mungkornasawakul, Stephen G. Pyne, Alison T. Ung, Thanapat Sastraruji

Faculty of Science - Papers (Archive)

To enhance the production of oxyprotostemonine, stemocurtisine and stemocurtisinol (the important insecticidal alkaloids) by root cultures of Stemona curtisii Hook. F. (Thai vernacular, Non Tai Yak, Family Stemonaceae). The roots were cultured on semi-solid MS medium containing 1 mg/L NAA with different concentrations of salicylic acid for 16 weeks. The quantity of the individual alkaloids was determined by HPLC. The highest production of oxyprotostemonine (7.192 mg/g dw), stemocurtisine (0.039 mg/g dw) and stemocurtisinol (0.197 mg/g dw) occurred when the roots were stimulated by 500 mg/L salicylic acid.

Understanding The Α-Crystallin Cell Membrane Conjunction, Shih-Ping Su, Jason D. Mcarthur, Michael G. Friedrich, Roger J. W Truscott, J. A. Aquilina

Faculty of Science - Papers (Archive)

PURPOSE. It is well established that levels of soluble α-crystallin in the lens cytoplasm fall steadily with age, accompanied by a corresponding increase in the amount of membrane-bound α-crystallin. Less well understood, is the mechanism driving this age-dependent membrane association. The aim of this study was to investigate the role of the membrane and its associated proteins and peptides in the binding of α-crystallin.

METHODS. Fibre cell membranes from human and bovine lenses were separated from soluble proteins by centrifugation. Membranes were stripped of associated proteins with successive aqueous, urea and alkaline solutions. Protein constituents of the respective membrane isolates …

Understanding The Conducting States Of Active And Passive Switches In An Inverter Circuit Used For Power System Applications, Danny Sutanto, B.P. Divakar, K.W.E. Cheng

Faculty of Informatics - Papers (Archive)

Bi-directional inverter circuits are commonly used in many applications in power systems, such as in FACTS devices, energy storage systems and active power filters. Many power engineering students however find it difficult to understand the conducting states of the active switches (transistors, IGBTs) and the passive switches (the antiparallel diodes connected across the active switches). It seems a mystery to them that power can flow from a lower voltage ac system to a higher voltage dc system to charge the energy storage system. This paper proposes a simple chart that intuitively explains how to determine the states (either conducting or …

T-S Fuzzy H Tracking Control Of Input Delayed Robotic Manipulators, Haiping Du, Weihua Li

Faculty of Informatics - Papers (Archive)

Time delays are often encountered by practical control systems while they are acquiring, processing, communicating, and sending signals. Time delays may affect the system stability and degrade the control system performance if they are not properly dealt with. Taking the classical robot control problem as an example, the significant effect of time delay on the closed-loop system stability has been highlighted in the bilateral teleoperation, where the communication delay transmitted through a network medium has been received widespread attention and different approaches have been proposed to address this problem (Hokayem and Spong, 2006). In addition, examples like processing delays in …

An Assessment Tool For E-Government System Performance: A Citizen-Centric Model, Shatha A. Al-Haddad, Peter Hyland, Geoffrey Hubona

Faculty of Informatics - Papers (Archive)

Governments worldwide have, increasingly, implemented e-government initiatives for their potential significant benefits; among which, delivering better services to citizens through increasing citizens' convenience, satisfaction, and independence; and saving their time, effort, and cost. Achieving each benefit is an objective to these governments and fulfilling each objective is considered a critical success factors. Hence, governments need to assess the extent to which they were able to obtain their preset goals. This study merely focuses on the citizens' perspective of the evaluation. However, the literature seems to lack studies that propose such a sufficient evaluation tool that has been reliably validated. Therefore, …

Potential Reduction In Energy Use From A High Speed Rail Network In Australia, Philip Laird

Faculty of Informatics - Papers (Archive)

High Speed Rail or HSR with electric passenger trains using steel wheels on steel rails with maximum operating speeds of 250km/h or more is now operational in 12 countries. It is now under review in Australia. The paper considers energy use on the 10 top routes of the Melbourne-Sydney and Sydney-Brisbane corridors and finds that HSR was in place by 2020, HSR could reduce the use of aviation fuel by over 450 million litres each year. External costs and Sydney airport issues are also noted.

Supporting Developers In Complex Systems Modelling, Antonio A. Lopez-Lorca, Ghassan Beydoun, Rodrigo Martinez-Bejar, Holly Tootell

Faculty of Informatics - Papers (Archive)

Development of complex systems often requires building a large number of models with many interconnections and dependencies among them. The success of a project can be compromised by cognitive overload or limits of developers, who might miss relationships between elements of the models. Developing Multi-Agent Systems (MAS) is a typical example of where this may occur. Despite of its potential, this technology has not yet been widely adopted by industry due to its complexity and frequent errors in modelling activities. These errors typically propagate to later phases of the MAS development lifecycle, becoming costlier to fix and then lowering the …

Sparsity Issues In Self-Organizing-Maps For Structures, Markus Hagenbuchner, Giovanni Da San Martino, Ah Chung Tsoi, Alessandro Sperduti

Faculty of Informatics - Papers (Archive)

Recent developments with Self-Organizing Maps (SOMs) produced methods capable of clustering graph structured data onto a fixed dimensional display space. These methods have been applied successfully to a number of benchmark problems and produced state-of-the-art results. This paper discusses a limitation of the most powerful version of these SOMs, known as probability measure graph SOMs (PMGraphSOMs), viz., the sparsity induced by processing a large number of small graphs, which prevents a successful application of PMGraphSOM to such problems. An approach using the idea of compactifying the generated state space to address this sparsity problem is proposed. An application to an …

Modelling The Effects Of Moisture Content In Compost Piles, T Luangwilai, H S. Sidhu, M I. Nelson, Xiao Dong Chen

Faculty of Informatics - Papers (Archive)

This paper considers the self-heating process occurring in a compost pile using one- and two-dimensional spatially-dependent models and incorporating terms that account for self-heating due to both biological and oxidative mechanisms. Biological heat generation is known to be present in most industrial processes handling large volumes of bulk organic materials. The heat release rate due to biological activity is modelled by a function which is, at sufficiently low temperatures, a monotonically increasing function of temperature and, at higher temperatures, a monotonically decreasing function of temperature. This functionality represents the fact that microorganisms die or become dormant at high temperatures. The …

Developing Measurements Of The Quality Of Electronic Versus Paper-Based Nursing Documentation In Australian Aged Care Homes, Ning Wang, Ping Yu, David Hailey, Deborah Oxlade

Faculty of Informatics - Papers (Archive)

Objective: To discuss the experience of developing approaches to measuring the quality of nursing documentation in residential aged care homes. Methods: Three information sources were reviewed to explore approaches in auditing nursing documentation: the current literature, relevant Australian legislative and professional requirements, and organizational nursing documentation practice. Results: Approaches suggested by the literature were mainly focused on three dimensions of nursing documentation: structure and format, process and content. The detailed standards of nursing documentation have been identified by reviewing the relevant Australian legislative and professional requirements and recommendations, and organizational nursing documentation practice. A nursing documentation audit instrument has been …

Spectral Density Estimation Through A Regularized Inverse Problem, Chunfeng Huang, Tailen Hsing, Noel Cressie

Faculty of Informatics - Papers (Archive)

In the study of stationary stochastic processes on the real line, the covariance function and the spectral density function are parameters of considerable interest. They are equivalent ways of expressing the temporal dependence in the process. In this article, we consider the spectral density function and propose a new estimator that is not based on the periodogram; the estimator is derived through a regularized inverse problem. A further feature of the estimator is that the data are not required to be observed on a grid. When the regularization condition is based on the function's first derivative, we give the estimator …

On Twisted Higher-Rank Graph C*-Algebras, Alex Kumjian, David A. Pask, Aidan Sims

Faculty of Informatics - Papers (Archive)

We define the categorical cohomology of a k-graph and show that the first three terms in this cohomology are isomorphic to the corresponding terms in the cohomology defined in our previous paper. This leads to an alternative characterisation of the twisted k-graph C*-algebras introduced there. We prove a gauge-invariant uniqueness theorem and use it to show that every twisted k-graph C*-algebra is isomorphic to a twisted groupoid C*-algebra. We deduce criteria for simplicity, prove a Cuntz-Krieger uniqueness theorem and establish that all twisted k-graph C*-algebras are nuclear and belong to the bootstrap class.

Gellan Gum Doped Polypyrrole Neural Prosthetic Electrode Coatings, Thomas M. Higgins, Simon E. Moulton, Kerry J. Gilmore, Gordon G. Wallace, Marc In Het Panhuis

Faculty of Science - Papers (Archive)

Surface modification of neural prosthetic electrodes with polymeric materials, in particular, conducting polymers and hydrogels, has the potential to circumvent many problems associated with currently used electrode platforms. These problems include the disparity in mechanical properties between implanted electrodes and host neural tissue and the lack of biofunctionality at the electrode surface, both of which dissuade favourable reception of the implanted device. We have developed conducting polymer electrode coatings doped with the polysaccharide gellan gum, as a platform for improved functionality of neural prosthetic electrodes. Our electrode coatings, prepared by galvanostatic electropolymerisation, significantly reduced the impedance magnitude at frequencies relevant …

Rocky Intertidal Temperature Variability Along The Southeast Coast Of Australia: Comparing Data From In Situ Loggers, Satellite-Derived Sst And Terrestrial Weather Stations, Justin Adam Lathlean, David J. Ayre Prof, Todd E. Minchinton

Faculty of Science - Papers (Archive)

Predicting how both spatial and temporal variation in sea and air temperature influence the distribution of intertidal organisms is a pressing issue. We used data from satellites, weather stations and in situ loggers to test the hypothesis that satellite-derived sea surface temperatures (SSTs) and weather station air temperatures provide accurate estimates of ambient temperature variability on rocky intertidal shores for temporal (hourly for 1 yr) and spatial (10 m to 400 km) variation along the southeast coast of Australia. We also tested whether satellites and weather stations accurately detect the duration, frequency and number of extreme temperature events. Daily mean …

Importance Of Secondary Sources In The Atmospheric Budgets Of Formic And Acetic Acids, Fabien Paulot, Debra Wunch, John D. Crounse, G C. Toon, Dylan B. Millet, Peter F. Decarlo, C Vigouroux, Nicholas M. Deutscher, G Gonzalez Abad, Justus Notholt, Thorsten Warneke, J Hannigan, Carsten Warneke, Joost A. De Gouw, Edward Dunlea, M De Maziere, David W. Griffith, P Bernath, J L. Jimenez, Paul O. Wennberg

Faculty of Science - Papers (Archive)

We present a detailed budget of formic and acetic acids, two of the most abundant trace gases in the atmosphere. Our bottom-up estimate of the global source of formic and acetic acids are ~1200 and ~1400 Gmol yr−1, dominated by photochemical oxidation of biogenic volatile organic compounds, in particular isoprene. Their sinks are dominated by wet and dry deposition. We use the GEOS-Chem chemical transport model to evaluate this budget against an extensive suite of measurements from ground, ship and satellite-based Fourier transform spectrometers, as well as from several aircraft campaigns over North America. The model captures the seasonality of …

Temporal Stability Of A Hybrid Swarm Between The Migratory Marine And Estuarine Fishes Acanthopagrus Australis And A. Butcheri, David G. Roberts, Charles A. Gray, Ronald J. West, David J. Ayre

Faculty of Science - Papers (Archive)

We predict estuaries to be hotspots of hybridisation between migratory marine and estuary-restricted species, although hybridisation rates may vary in space and time, reflecting the dynamic nature of estuaries and potentially widespread but erratic dispersal of marine taxa. Within estuaries, genotype frequencies may reflect past hybridisation events, with genetically intermediate and backcrossed individuals contributing to persistent hybrid swarms. In southeastern Australia, hybridisation has occurred between estuarine black bream Acanthopagrus butcheri and marine yellowfin bream A. australis, but it is unclear whether this reflects a contemporary process. We recently found that, within lakes and lagoons at the southern range limit of …

The Art Of Learning: Wildfire, Amenity Migration And Local Environmental Knowledge, Christine Eriksen, T Prior

Faculty of Science - Papers (Archive)

Communicating the need to prepare well in advance of the wildfire season is a strategic priority for wildfire management agencies worldwide. However, there is considerable evidence to suggest that although these agencies invest significant effort towards this objective in the lead up to each wildfire season, landholders in at-risk locations often remain under-prepared. One reason for the poor translation of risk information materials into actual preparation may be attributed to the diversity of people now inhabiting wildfire-prone locations in peri-urban landscapes. These people hold widely varying experiences, beliefs, attitudes and values relating to wildfire, which influence their understanding and interpretation …

Integrated Coastal Zone Management Research In Australia And China, X H. Wang, X Xu, S G. Pearson, G Xue, Robert J. Morrison, D Liu, P Shi

Faculty of Science - Papers (Archive)

This paper reviews the current Integrated and Coastal Zone Management (ICZM) research in coastal zone science and policy for Australia and China. It seeks to make a coherent contribution to understanding the Chinese and Australian research and management through a brief description of the similarities and differences in an integrated way. The paper draws together the research needs for the ICZM in both countries with the aim of justifying the research investments needed in the future. Based on this review, we recommend five research programs: Coastal Ocean Observing and Forecasting System and its Socio-economic Impact; Review and Utilization of Space-borne …

In The Heat Of The Night - Alternative Pathway Respiration Drives Thermogenesis In Philodendron Bipinnatifidum, Rebecca Miller, N. Grant, L. Giles, Miquel Ribas-Carbo, J. A. Berry, Jennifer Watling, Sharon A. Robinson

Faculty of Science - Papers (Archive)

Philodendron bipinnatifidum inflorescences heat up to 42ºC and thermoregulate. We investigated whether they generate heat via the cytochrome oxidase pathway uncoupled by uncoupling proteins (pUCPs), or the alternative oxidase (AOX). Contribution of AOX and pUCPs to heating in fertile (FM) and sterile (SM) male florets was determined using a combination of oxygen isotope discrimination, protein and substrate analyses. FM and SM florets thermoregulated independently for up to 30h ex planta. In both floret types, AOX contributed more than 90% of respiratory flux during peak heating. AOX protein increased 5-fold with the onset of thermogenesis in both floret types, whereas pUCP …

Digit Ratio, Color Polymorphism And Egg Testosterone In The Australian Painted Dragon, Michael Tobler, Mo Healey, Mats Olsson

Faculty of Science - Papers (Archive)

Variation in exposure to sex hormones during early development contributes to phenotypic plasticity in vertebrate offspring. As a proposed marker for prenatal sex hormone exposure and because of their association with various physiological and behavioral characteristics, digit ratio and/or digit length have received notable interest within the field of evolutionary ecology. However, the validity of digit measures as a proxy of prenatal sex hormone exposure is controversial and only few studies have provided direct evidence for the link between digit development and prenatal sex hormones. Here, we report morph- and sex-specific variation in digit ratio in wild painted dragon lizards …

Speciation Of Dissolved Inorganic Arsenic By Diffusive Gradients In Thin Films: Selective Binding Of Asiii By 3-Mercaptopropyl-Functionalized Silica Gel, William W. Bennett, Peter R. Teasdale, Jarad G. Panther, David T. Welsh, Dianne F. Jolley

Faculty of Science - Papers (Archive)

A diffusive gradients in thin films (DGT) technique for selectively measuring AsIII utilizes commercially available 3-mercaptopropyl- functionalized silica gel. Deployment of the new technique alongside the Metsorb-DGT for total inorganic arsenic allows the calculation of As III directly and AsV by difference. Uptake of As III by mercapto-silica was quantitative and elution with a mixture of 1 mol L-1 HNO3 and 0.01 mol L-1 KIO 3 gave a recovery of 85.6 + 1.7%. DGT validation experiments showed linear accumulation of AsIII over time (R2 > 0.998). Accumulation was unaffected by varying ionic strength (0.0001-0.75 mol L-1 NaNO3) and pH (3.5-8.5). Deployment …

Integrating The Projective Transform With Particle Filtering For Visual Tracking, Philippe L. Bouttefroy, Abdesselam Bouzerdoum, Son Lam Phung, A. Beghdadi

Faculty of Informatics - Papers (Archive)

This paper presents the projective particle filter, a Bayesian filtering technique integrating the projective transform, which describes the distortion of vehicle trajectories on the camera plane. The characteristics inherent to traffic monitoring, and in particular the projective transform, are integrated in the particle filtering framework in order to improve the tracking robustness and accuracy. It is shown that the projective transform can be fully described by three parameters, namely, the angle of view, the height of the camera, and the ground distance to the first point of capture. This information is integrated in the importance density so as to explore …

A Hot Metal Temperature Predictor Based On Hybrid Decision Tree Techniques, Chao Sun, David A. Stirling, Bryan Wright, Paul Zulli, Christian Ritz

Faculty of Informatics - Papers (Archive)

HEAT level control (HLC) is one of the important elements for operating an iron-making blast furnace (BF). The goal of HLC is to maintain the hot metal temperature (HMT) as close to a preset aim as possible. HMT is an important indicator of both the product quality and fuel efficiency, and is measured from tapped out liquid iron. For instance, high values of HMT mean unnecessary fuel consumption together with sub-optimal hot metal chemistry, whilst low values of HMT may indicate insufficient fuel consumption, which may consequently lead to dangerous situation of freezing the slag inside the BF. Once an …

The Analytical Evolution Of Nls Solitons Due To The Numerical Discretization Error, S. M. Hoseini, Timothy R. Marchant

Faculty of Informatics - Papers (Archive)

Soliton perturbation theory is used to obtain analytical solutions describing solitary wave tails or shelves, due to numerical discretization error, for soliton solutions of the nonlinear Schr¨odinger equation. Two important implicit numerical schemes for the nonlinear Schr¨odinger equation, with second-order temporal and spatial discretization errors, are considered. These are the Crank– Nicolson scheme and a scheme, due to Taha [1], based on the inverse scattering transform. The first-order correction for the solitary wave tail, or shelf, is in integral form and an explicit expression is found for large time. The shelf decays slowly, at a rate of t−12 , which …

An Ontology-Based Collaborative Interorganizational Knowledge Management Network, Nelson K. Y. Leung, Sim Kim Lau, Joshua P. Fan, Seung Hwan Kang, Nicole Tsang

Faculty of Informatics - Papers (Archive)

Web contents can be represented in a structural form by a finite list of vocabularies and their relationships using ontologies. The concept of ontology and its related mediation methods is capable of enhancing the collaboration among Knowledge Management (KM) approaches that only focus on managing organizational knowledge. Those KM approaches are developed in accordance with organizational KM strategies and business requirements without the concern of system interoperation. In this research, an ontology-based collaborative inter-organizational KM network is proposed to provide a platform for organizations to access and retrieve inter-organizational knowledge in a similar domain.

Trust-Based Service Provider Selection In Service-Oriented Environments, Minjie Zhang, Yi Mu, Q. Bai

Faculty of Informatics - Papers (Archive)

Nowadays, agent-based service-oriented systems have been widely applied in many complex domains such as e-markets, grid systems, e-governments and service-oriented software systems, cross Internet and organizations. In this kind of service-oriented multi-agent systems, service providers (agents) and service consumers (agents) are autonomous entities and can enter and leave environments freely. How to select the most suitable service providers according to the requested services from consumers in such an open and dynamic environment is a very challenging issue. The objectives of this paper include (1) studying the challenging issues of trust-based service provider selection, (2) investigating the current approaches of trust …

Self-Similar Solutions Of Fully Nonlinear Curvature Flows, James Alexander Mccoy

Faculty of Informatics - Papers (Archive)

We consider closed hypersurfaces which shrink self-similarly under a natural class of fully nonlinear curvature flows. For those flows in our class with speeds homogeneous of degree 1 and either convex or concave, we show that the only such hypersurfaces are shrinking spheres. In the setting of convex hypersurfaces, we show under a weaker second derivative condition on the speed that again only shrinking spheres are possible. For surfaces this result is extended in some cases by a different method to speeds of homogeneity greater than 1. Finally we show that self-similar hypersurfaces with sufficiently pinched principal curvatures, depending on …