Physical Sciences and Mathematics Commons^™

Motion Estimation With Adaptive Regularization And Neighborhood Dependent Constraint, Muhammad Wasim Nawaz, Abdesselam Bouzerdoum, Son Lam Phung

Faculty of Informatics - Papers (Archive)

Modern variational motion estimation techniques use total variation regularization along with the L1 norm in constant brightness data term. An algorithm based on such homogeneous regularization is unable to preserve sharp edges and leads to increased estimation errors. A better solution is to modify regularizer along strong intensity variations and occluded areas. In addition, using neighborhood information with data constraint can better identify correspondence between image pairs than using only a pointwise data constraint. In this work, we present a novel motion estimation method that uses neighborhood dependent data constraint to better characterize local image structure. The method also uses …

Automatic Recognition Of Smiling And Neutral Facial Expressions, Peiyao Li, S L. Phung, Abdesselam Bouzerdoum, Fok Hing Chi Tivive

Faculty of Informatics - Papers (Archive)

Facial expression is one way humans convey their emotional states. Accurate recognition of facial expressions via image analysis plays a vital role in perceptual human computer interaction, robotics and online games. This paper focuses on recognising the smiling from the neutral facial expression. We propose a face alignment method to address the localisation error in existing face detection methods. In this paper, smiling and neutral facial expression are differentiated using a novel neural architecture that combines fixed and adaptive non-linear 2-D filters. The fixed filters are used to extract primitive features, whereas the adaptive filters are trained to extract more …

Inter-Domain Routing Validator Based Spoofing Defence System, Lei Wang, Tianbing Xia, Jennifer Seberry

Faculty of Informatics - Papers (Archive)

IP spoofing remains a problem today in the Internet. In this paper, a new system called Inter-Domain Routing Validator Based Spoofing Defence System (SDS) for filtering spoofed IP packets is proposed . SDS uses efficient symmetric key message authentication code (UMAC) as its tag to verify that a source IP address is valid. Different ASes border routers obtain a shared key via the Inter-Domain Routing Validator (IRV) servers which will manage the secret keys and exchange keys among different ASes via security communication channel. SDS is efficient, secure and easy to cooperate with other defence mechanisms.

Differential Fault Analysis Of Lex, Jianyong Huang, Willy Susilo, Jennifer Seberry

Faculty of Informatics - Papers (Archive)

LEX is a stream cipher based on the round transformation of the AES block cipher, and it was selected for the final phase evaluation of the eSTREAM project. LEX is 2.5 times faster than AES both in software and in hardware. In this paper, we present a differential fault attack on LEX. The fault model assumes that the attacker is able to flip a random bit of the internal state of the cipher but cannot control the exact location of the induced fault. Our attack requires 40 faults, and recovers the secret key with 216 operations.

Social Tagging For Digital Libraries Using Formal Concept Analysis, Timothy Wray, Peter W. Eklund

Faculty of Informatics - Papers (Archive)

This paper describes the Art Collection Ecosystem – an application that allows users to tag and serendipitously browse content using Formal Concept Analysis. Within this application, tags are derived from meta-data of artworks within an existing asset management system and are classified according to theories derived from social tagging behaviour.We present past and recent iterations of its design, where it is evaluated as a contextual comparison to a popular image tagging application, Flickr. Through the process of iterative design and user evaluation, we produce results are of interest to any applied research and development that involves the exploration of digital …

Estimating Shared Copy Number Aberrations For Array Cgh Data: The Linear-Median Method, Yan-Xia Lin, Veera Baladandayuthapani, V Bonato, K.-A. Do

Faculty of Informatics - Papers (Archive)

Motivation: Existing methods for estimating copy number variations in array comparative genomic hybridization (aCGH) data are limited to estimations of the gain/loss of chromosome regions for single sample analysis. We propose the linear-median method for estimating shared copy numbers in DNA sequences across multiple samples, demonstrate its operating characteristics through simulations and applications to real cancer data, and compare it to two existing methods.

Results: Our proposed linear-median method has the power to estimate common changes that appear at isolated single probe positions or very short regions. Such changes are hard to detect by current methods. This new …

Probabilistic Neural Network For Vulnerability Prediction On A Practical Power System, Ahmed Haidar, Zulkeflee Khalidin, Ibrahim Abdulrab Ahmed

Faculty of Informatics - Papers (Archive)

Vulnerability prediction of power systems is important so as to determine its ability to continue to provide service in case of any unforeseen catastrophic contingency. It is considered one of the vital concerns due to the continual blackouts in recent years which indicate that the power system today is too vulnerable to withstand a severer disturbance. The objective of this paper is to investigate and compare the performance of two vulnerability indices used for assessing the vulnerability of power systems when subjected to various contingencies. The Probabilistic Neural Network (PNN) based on power system loss and possible loss of load …

A Longer Look At The Asymmetric Dependence Between Hedge Funds And The Equity Market, Byoung Kang, Francis In, Gunky Kim, Tong Kim

Faculty of Informatics - Papers (Archive)

This paper reexamines, at a range of investment horizons, the asymmetric dependence between hedge fund returns and market returns. Given the current availability of hedge fund data, the joint distribution of longer-horizon returns is extracted from the dynamics of monthly returns using the filtered historical simulation; we then apply the method based on copula theory to uncover the dependence structure therein. While the direction of asymmetry remains unchanged, the magnitude of asymmetry is attenuated considerably as the investment horizon increases. Similar horizon effects also occur on the tail dependence. Our findings suggest that nonlinearity in hedge fund exposure to market …

Analysis Of A Model For Ethanol Production Through Continuous Fermentation: Ethanol Productivity, Simon Watt, Harvinder Sidhu, Mark Nelson, Ajay Ray

Faculty of Informatics - Papers (Archive)

We investigate a model for the production of ethanol through continuous fermentation using Saccharomyces cerevisiae in a single reactor and cascades of up to five reactors. Using path-following methods we investigate how the ethanol productivity varies with the residence time in each reactor of the cascade. With a substrate feed concentration of 160 g/l we find the optimal productivity is 3.80 g/l/h, 5.08 g/l/h, and 5.18 g/l/h in a single reactor, a double reactor cascade and a triple reactor cascade respectively. For the case of a cascade containing reactors of equal size we investigate reactor configurations of up to five …

Managing The Matrix: Decadal Responses Of Eucalypt-Dominated Savanna To Ambient Fire Regimes, Jeremy Russell-Smith, O Price, Brett Murphy

Faculty of Science - Papers (Archive)

Much of our understanding of the response of savanna systems to fire disturbance relies on observations derived from manipulative fire plot studies. Equivocal findings from both recent Australian and African savanna fire plot assessments have significant implications for informing conservation management and reliable estimation of biomass stocks and dynamics. Influential northern Australian replicated fire plot studies include the 24-year plot-scale Munmarlary and the five-year catchment-scale Kapalga, mesic savanna ( . 1000 mm/yr of rainfall) experiments in present-day Kakadu National Park. At Munmarlary, under low-to-moderate-intensity fire treatments, woody vegetation dominated by mature eucalypts was found to be structurally stable. At Kapalga, …

Global Estimates Of Co Sources With High Resolution By Adjoint Inversion Of Multiple Satellite Datasets (Mopitt, Airs, Sciamachy, Tes), M Kopacz, D J. Jacob, J A. Fisher, J A. Logan, L Zhang, I A. Megretskaia, R M. Yantosca, K Singh, D K. Henze, J P. Burrows, M Buchwitz, I Khlystova, W. W Mcmillan, J C. Gille, D P. Edwards, A Eldering, V Thouret, P Nedelec

Faculty of Science - Papers (Archive)

We combine CO column measurements from the MOPITT, AIRS, SCIAMACHY, and TES satellite instruments in a full-year (May 2004–April 2005) global inversion of CO sources at 4◦ ×5◦ spatial resolution and monthly temporal resolution. The inversion uses the GEOS-Chem chemical transport model (CTM) and its adjoint applied to MOPITT, AIRS, and SCIAMACHY. Observations from TES, surface sites (NOAA/GMD), and aircraft (MOZAIC) are used for evaluation of the a posteriori solution. Using GEOSChem as a common intercomparison platform shows global consistency between the different satellite datasets and with the in situ data. Differences can be largely explained by different averaging kernels …

Source Attribution And Interannual Variability Of Arctic Pollution In Spring Constrained By Aircraft (Arctas, Arcpac) And Satellite (Airs) Observations Of Carbon Monoxide, J A. Fisher, D J. Jacob, M T. Purdy, M Kopacz, P Le Sager, C C. Carouge, C D. Holmes, R M. Yantosca, R L. Batchelor, K Strong, G S. Diskin, H E. Fuelberg, J S. Holloway, E J. Hyer, W. W Mcmillan, J Warner, D G. Streets, Q Zhang, Y Yang, S Wu

Faculty of Science - Papers (Archive)

We use aircraft observations of carbon monoxide (CO) from the NASA ARCTAS and NOAA ARCPAC campaigns in April 2008 together with multiyear (2003– 2008) CO satellite data from the AIRS instrument and a global chemical transport model (GEOS-Chem) to better understand the sources, transport, and interannual variability of pollution in the Arctic in spring. Model simulation of the aircraft data gives best estimates of CO emissions in April 2008 of 26 Tg month−1 for Asian anthropogenic, 9.4 for European anthropogenic, 4.1 for North American anthropogenic, 15 for Russian biomass burning (anomalously large that year), and 23 for Southeast Asian biomass …

An Australian Feeling For Snow Towards Understanding Cultural And Emotional Dimensions Of Climate Change, Andrew W. Gorman-Murray

Faculty of Science - Papers (Archive)

In Australia, snow is associated with alpine and subalpine regions in rural areas; snow is a component of ‘natural’ rather than urban environments. But the range, depth and duration of Australia’s regional snow cover is imperilled by climate change. While researchers have considered the impacts of snow retreat on the natural environment and responses from the mainland ski industry, this paper explores associated cultural and emotional dimensions of climate change. This responds to calls to account for local meanings of climate, and thus localised perceptions of and responses to climate change. Accordingly, this paper presents a case study of reactions …

Introduction - Doing Rural Cultural Studies, Clifton Evers, Andrew W. Gorman-Murray, Emily Potter

Faculty of Science - Papers (Archive)

In 2008, a themed section of Australian Humanities Review began the task of establishing the emerging field of ‘Rural Cultural Studies’. As the editors pointed out, ‘contemporary cultural studies researchers internationally and in Australia have been massively biased towards urban popular cultures’.

'The Falling Sky': Symbolic And Cosmological Associations Of The Mt William Greenstone Axe Quarry, Central Victoria, Australia, Adam R. Brumm

Faculty of Science - Papers (Archive)

This article examines the roles of socio-symbolic practices and cosmological beliefs in the production and exchange of stone artefacts in an ethnohistorically documented context in Australia. Isabel McBryde's petrological and ethnohistorical analysis of greenstone axe distribution patterns in central Victoria provides a key example of social factors overriding technological concerns in the production and exchange of lithic artefacts. Her research shows that greenstone axes from Mt William quarry were distributed further than axes from equivalent sources. This suggests that Mt William stone axes had symbolic values that cannot be appreciated from straightforward economic perspectives - the aim of this article …

Elastic Conducting Carbon Nanotube-Laden Sibs Fibers, Alberto J. Granero, Joselito M. Razal, Gordon G. Wallace, Marc In Het Panhuis

Faculty of Science - Papers (Archive)

We report a facile method to produce elastic conducting fibers using a continuous flow wet-spinning approach. The spun fibers were highly stretchable, similar to the elastomeric polymer used.

Printed Hydrogel Materials, Donald J. Mccallum, Cameron J. Ferris, Paul D. Calvert, Gordon G. Wallace, Marc In Het Panhuis

Faculty of Science - Papers (Archive)

No abstract provided.

Impact Of Ocean Warming And Ocean Acidification On Larval Development And Calcification In The Sea Urchin Tripneustes Gratilla, Hannah Sheppard Brennand, Natalie Soars, Symon A. Dworjanyn, Andrew R. Davis, Maria Byrne

Faculty of Science - Papers (Archive)

Background: As the oceans simultaneously warm, acidify and increase in P-CO2, prospects for marine biota are of concern. Calcifying species may find it difficult to produce their skeleton because ocean acidification decreases calcium carbonate saturation and accompanying hypercapnia suppresses metabolism. However, this may be buffered by enhanced growth and metabolism due to warming.Methodology/Principal Findings: We examined the interactive effects of near-future ocean warming and increased acidification/P-CO2 on larval development in the tropical sea urchin Tripneustes gratilla. Larvae were reared in multifactorial experiments in flow-through conditions in all combinations of three temperature and three pH/P-CO2 treatments. Experiments were placed in the …

Ecological System Meets 'Digital Ecosystem': Can Ict Benefit From Understanding Biology?, Robert J. Whelan

Faculty of Science - Papers (Archive)

The description of a digital ecosystem as a “loosely coupled, demand-driven, domain clustered, agent-based, self organised, collaborative environment where agents form temporary coalitions for a specific purpose or goal, and each is proactive and responsive for its own benefit” has intriguing similarities with the definition of an ecosystem in ecology. Perhaps the similarities suggest that a deeper understanding of ecology may benefit the further development of ICT, and any differences may therefore represent cautionary tales. In this presentation, I describe characteristics of some ecological systems at several levels-from species to ecosystem-and speculate on the potential of these examples to catalyse …

Carboxymethylated-K-Casein: A Convenient Tool For The Identification Of Polyphenolic Inhibitors Of Amyloid Fibril Formation, John A. Carver, Peter J. Duggan, Heath Ecroyd, Yanqin Liu, Adam G. Meyer, C E. Tranberg

Faculty of Science - Papers (Archive)

Reduced and carboxymethylated-κ-casein (RCM-κ-CN) is a milk-derived amyloidogenic protein that readily undergoes nucleation-dependent aggregation and amyloid fibril formation via a similar pathway to disease-specific amyloidogenic peptides like amyloid beta (Aβ), which is associated with Alzheimer’s disease. In this study, a series of flavonoids, many known to be inhibitors of Aβ fibril formation, were screened for their ability to inhibit RCM-κ-CN fibrilisation, and the results were compared with literature data on Aβ inhibition. Flavonoids that had a high degree of hydroxylation and molecular planarity gave good inhibition of RCM-κ-CN fibril formation. IC50 values were between 10- and 200-fold higher with RCM-κ-CN …

The Interaction Of Unfolding Α-Lactalbumin And Malate Dehydrogenase With The Molecular Chaperone Αb-Crystallin: A Light And X-Ray Scattering Investigation, J W. Regini, Heath Ecroyd, Sarah Meehan, Kristen Bremmell, Matthew J. Clarke, Donna Lammie, Tim Wess, John A. Carver

Faculty of Science - Papers (Archive)

Purpose: The molecular chaperone αB-crystallin is found in high concentrations in the lens and is present in all major body tissues. Its structure and the mechanism by which it protects its target protein from aggregating and precipitating are not known. Methods: Dynamic light scattering and X-ray solution scattering techniques were used to investigate structural features of the αB-crystallin oligomer when complexed with target proteins under mild stress conditions, i.e., reduction of α- lactalbumin at 37 °C and malate dehydrogenase when heated at 42 °C. In this investigation, the size, shape and particle distribution of the complexes were determined in real-time …

Indigenous Environmental Knowledge, Christine Eriksen, Michael J. Adams

Faculty of Science - Papers (Archive)

No abstract provided.

Protein Chemistry Of Amyloid Fibrils And Chaperones: Implications For Amyloid Formation And Disease, Justin J. Yerbury, Janet R. Kumita

Faculty of Science - Papers (Archive)

Understanding the mechanisms by which amyloid fibrils are formed, both in vivo and in vitro, is vital for developing methods to treat and prevent debilitating deposition diseases such as Alzheimer's disease, Parkinson's disease, type II diabetes and systemic amyloidoses. In recent years, computer modelling and biophysical studies have broadened our understanding of the biochemical mechanisms underpinning protein aggregation. As a result, it is now believed that the ability to form fibrils is an intrinsic property of polypeptide chains and not isolated to disease-related proteins or peptides. Molecular chaperones are a diverse group of functionally related proteins well known for their …

Interpreting New England Subduction Complex Rocks Using Deep-Sea Drilling Results From The Nankai Trough (Offshore Southwest Japan), Christopher L. Fergusson

Faculty of Science - Papers (Archive)

Two distinct structural styles are considered likely to have affected parts of the subduction complex of the New England Orogen. Imbricate thrusting, as occurs by duplexing at a ramp along the décollement at the base of the subduction complex, accounts for the structure of units such as the Gundahl Complex (also the Wandilla Formation of central Queensland and the Sandon beds of the Armidale district). These units have relatively straight-forward imbricate structure although in the case of the Gundahl Complex the thickness of units is condensed and reflects factors controlling deposition on the ocean plate and in the trench. In …

Stewardship Among Lifestyle Oriented Rural Landowners, Nicholas J. Gill, Peter Klepeis, Laurie A. Chisholm

Faculty of Science - Papers (Archive)

Changes in landownership associated with amenity migration are affecting the demographic, cadastral and ecological conditions of rural landscapes. These changes and concerns about their impacts on natural resource management, including ecological conservation, relate to both the structural consequences of landownership change, land subdivision and to the motivations, management ability and attitudes of lifestyle oriented rural landowners. Based on an Australian case study near Sydney, NSW, this paper examines the motivations and practices of such landowners, assesses potential consequences for vegetation and characterises the landowners according to three stewardship types.

Late Quaternary Aeolian And Fluvial Interactions On The Cooper Creek Fan And The Association Between Linear And Source-Bordering Dunes, Strzelecki Desert, Australia, Timothy J. Cohen, Gerald C. Nanson, Joshua R. Larsen, B. G. Jones, David M. Price, Maria Coleman, Tim Pietsch

Faculty of Science - Papers (Archive)

The Innamincka Dome and associated low-gradient fan in the Strzelecki Desert is the product of Cenozoic crustal warping that has aided formation of an extensive array of palaeochannels, source-bordering transverse dunes and superimposed linear dunes. These dunes have impeded the course of Cooper Creek and provided a repository of evidence for Quaternary climate change as well as the interactive processes between transverse and linear dune formation. At Turra, Gidgealpa and sites nearby are extensive fluvial and aeolian sand bodies that date from marine isotope stages (MIS) 8-3 and the Last Glacial Maximum (LGM) and are now surrounded or buried by …

Formaldehyde And Nitrogen Dioxide In Smoke Plumes From Australia's Black Saturday Fires, Emma Young, Clare Paton-Walsh

Faculty of Science - Papers (Archive)

The ‘Black Saturday’ fires were a series of devastating bushfires that burned across Victoria, Australia, during February 2009. The smoke plume from Saturday the 7th February, the worst day of the fires, separated from subsequent emissions and persisted for several weeks, providing the opportunity to track the changing composition of the smoke plume as it aged. In this study we have used satellite data from the Ozone Monitoring Instrument (OMI) and the Atmospheric InfraRed Sounder (AIRS) to characterise the emissions of formaldehyde and nitrogen dioxide from the fires. Emission ratios with respect to carbon monoxide are determined for formaldehyde (0.017 …

A Method For Monitoring Ink Homogeneity, Xinshi Luo, Siva Balakrishnan, Gerhard F. Swiegers

Faculty of Science - Papers (Archive)

An important concern when developing new inks containing novel, bulk, solid-state additives is to ensure consistency during the printing process. In particular, the additives should not build up on the rollers, blankets or plates during printing. In this work we describe a method for detecting such events and quantitatively monitoring, in real time, the consistency of developmental inks during commercial printing processes. The technique employs a two-component mixture of emissive nanoparticles whose ratio becomes variable in a non-homogeneous environment. Even tiny variations in the ratio can be readily and dynamically detected in real time using a fibre-optic equipped fluorescence microspectrometer. …

Aerial ‘Oktokopter’ To Map Antarctic Moss, Arko Lucieer, Sharon A. Robinson, Dana Bergstrom

Faculty of Science - Papers (Archive)

Polar regions are experiencing rapid and severe climatic shifts with major changes in temperature, wind speed and UV-B radiation already observed in Antarctica. As climatic records only extend back 50 years, we urgently need new proxies to determine if coastal climate has changed over the past century.

Detection And Quantification Of Tear Phospholipids And Cholesterol In Contact Lens Deposits: The Effect Of Contact Lens Material And Lens Care Solution, Jennifer Saville, Zhenjun Zhao, Mark D.P. Willcox, Stephen J. Blanksby, Todd W. Mitchell

Faculty of Science - Papers (Archive)

PURPOSE. To examine the deposition of tear phospholipids and cholesterol onto worn contact lenses and the effect of lens material and lens care solution. METHODS. Lipids were extracted from tears and worn contact lenses using 2: 1 chloroform: methanol and the extract washed with aqueous ammonium acetate, before analysis by electrospray ionization tandem mass spectrometry (ESI-MS/MS). RESULTS. Twenty-three molecular lipids from the sphingomyelin (SM) and phosphatidylcholine (PC) classes were detected in tears, with total concentrations of each class determined to be 5 +/- 1 pmol/mu L (similar to 3.8 mu g/mL) and 6 +/- 1 pmol/mu L (similar to 4.6 …