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Full-Text Articles in Physical Sciences and Mathematics

Using Singularity Theory To Analyse A Spatially Uniform Model Of Self-Heating In Compost Piles, Thiansiri Luangwilai, Harvinder Sidhu, Mark Nelson, Xiao Dong Chen Jan 2010

Using Singularity Theory To Analyse A Spatially Uniform Model Of Self-Heating In Compost Piles, Thiansiri Luangwilai, Harvinder Sidhu, Mark Nelson, Xiao Dong Chen

Faculty of Informatics - Papers (Archive)

Fires at industrial composting facilities, such as those storing industrial waste products like municipal solid waste (NSW) and landfills are fairly common. In most cases these are manageable and such incidents are not destructive enough to attract attention beyond these facilities. However, over the years there have been a few notable devastating fires at such facilities.

In each of these industrial processes there is an inherent increase in temperature as a consequence of the biological activity. Indeed such a temperature increase is one of the goals of the composting waste. Elevated temperatures of the order of 70-90 degrees celsius have …


Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim Jan 2010

Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim

Faculty of Informatics - Papers (Archive)

How to choose the best service provider (agent), which a service consumer can trust in terms of the quality and success rate of the service in an open and dynamic environment, is a challenging problem in many service-oriented applications such as Internet-based grid systems, e-trading systems, as well as service-oriented computing systems. This paper presents a Priority-Based Trust (PBTrust) model for service selection in general service-oriented environments. The PBTrust is robust and novel from several perspectives. (1) The reputation of a service provider is derived from referees who are third parties and had interactions with the provider in a rich …


Dynamic Trust Model For Federated Identity Management, Hao Gao, Jun Yan, Yi Mu Jan 2010

Dynamic Trust Model For Federated Identity Management, Hao Gao, Jun Yan, Yi Mu

Faculty of Informatics - Papers (Archive)

The goal of federated identity management is to allow principals, such as identities and attributes, to be shared across trust boundaries based on established policies. Since current Single Sign-On (SSO) mechanism excessively relies on the specifications of Circle of Trust (CoT), the need for service collaboration from different domains is being addressed on CoT. For the motivating issue of the cross-domain SSO mechanism, we need an emergent dynamic trust list for calculating the trust parties, thus, the CoT specifications require an initial effort on enrolling members automatically to adapt to the dynamic open environment. In this paper, we propose a …


Application Of A Simple Hydrodynamic Model To Estuary Entrance Management, Errol J. Mclean, Jon B. Hinwood Jan 2010

Application Of A Simple Hydrodynamic Model To Estuary Entrance Management, Errol J. Mclean, Jon B. Hinwood

Faculty of Science - Papers (Archive)

Tidal inlets which link a tidal basin to the sea via a constricted entrance are common on the south-east Australian coast. Closure, or even significant constriction, raises water levels but restricts tidal range within the basin, while open entrances provide regular and significant tidal exchange with the ocean. A rapid assessment procedure with minimal data requirements has been shown to be informative for monitoring and a useful component of any Decision Support System set up as part of a management structure. Such a system is presented in this paper. It is based on one permanent water level gauge inside the …


A Spatial Agent-Based Model To Explore Scenarios Of Adaptation To Climate Change In An Alpine Tourism Destination, Stefano Balbi, Pascal Perez, Carlo Giupponi Jan 2010

A Spatial Agent-Based Model To Explore Scenarios Of Adaptation To Climate Change In An Alpine Tourism Destination, Stefano Balbi, Pascal Perez, Carlo Giupponi

SMART Infrastructure Facility - Papers

A vast body of literature suggests that the European Alpine region may be one of the most sensitive to climate change impacts. Adaptation to climate change of Alpine socioecosystems is increasingly becoming an issue of interest for the scientific community while the people of the Alps are often unaware of or simply ignore the problem. ClimAlpTour is a European research project of the Alpine Space Programme, bringing together institutions and scholars from all countries of the Alpine arch, in view of dealing with the expected decrease in snow and ice cover, which may lead to a rethinking of tourism development …


Intelligent Negotiation Behaviour Model For An Open Railway Access Market, S K. Wong, T K. Ho Jan 2010

Intelligent Negotiation Behaviour Model For An Open Railway Access Market, S K. Wong, T K. Ho

SMART Infrastructure Facility - Papers

In an open railway access market, the provisions of railway infrastructures and train services are separated and independent. Negotiations between the track owner and train service providers are thus required for the allocation of the track capacity and the formulation of the services timetables, in which each party, i.e. a stakeholder, exhibits intelligence from the previous negotiation experience to obtain the favourable terms and conditions for the track access. In order to analyse the realistic interacting behaviour among the stakeholders in the open railway access market schedule negotiations, intelligent learning capability should be included in the behaviour modelling. This paper …


Estimated Total Emissions Of Trace Gases From The Canberra Wildfires Of 2003: A New Method Using Satellite Measurements Of Aerosol Optical Depth & The Mozart Chemical Transport Model, Clare Paton-Walsh, L Emmons, Stephen R. Wilson Jan 2010

Estimated Total Emissions Of Trace Gases From The Canberra Wildfires Of 2003: A New Method Using Satellite Measurements Of Aerosol Optical Depth & The Mozart Chemical Transport Model, Clare Paton-Walsh, L Emmons, Stephen R. Wilson

Faculty of Science - Papers (Archive)

In this paper we describe a new method for estimating trace gas emissions from large vegetation fires using satellite measurements of aerosol optical depth (AOD) at 550 nm, combined with an atmospheric chemical transport model. The method uses a threshold value to screen out normal levels of AOD that may be caused by raised dust, sea salt aerosols or diffuse smoke transported from distant fires. Using this method we infer an estimated total emission of 15±5 Tg of carbon monoxide, 0.05±0.02 Tg of hydrogen cyanide, 0.11±0.03 Tg of ammonia, 0.25±0.07 Tg of formaldehyde, 0.03±0.01 of acetylene, 0.10±0.03 Tg of ethylene, …


The Importance Of Transport Model Uncertainties For The Estimation Of Co2 Sources And Sinks Using Satellite Measurements, S Houweling, I Aben, F.-M Breon, F Chevallier, N Deutscher, R Engelen, C Gerbig, D Griffith, K Hungershoefer, R Macatangay, J Marshall, J Notholt, W Peters, S Serrar Jan 2010

The Importance Of Transport Model Uncertainties For The Estimation Of Co2 Sources And Sinks Using Satellite Measurements, S Houweling, I Aben, F.-M Breon, F Chevallier, N Deutscher, R Engelen, C Gerbig, D Griffith, K Hungershoefer, R Macatangay, J Marshall, J Notholt, W Peters, S Serrar

Faculty of Science - Papers (Archive)

This study presents a synthetic model intercomparison to investigate the importance of transport model errors for estimating the sources and sinks of CO2 using satellite measurements. The experiments were designed for testing the potential performance of the proposed CO2 lidar A-SCOPE, but also apply to other space borne missions that monitor total column CO2. The participating transport models IFS, LMDZ, TM3, and TM5 were run in forward and inverse mode using common CO2 fluxes and initial concentrations. Simulated column averaged CO2 (xCO 2) mixing ratios vary between the models by σCombining double low line0.5 ppm over the continents and σCombining …


Co-Located Column And In Situ Measurements Of Co2 In The Tropics Compared With Model Simulations, T Warneke, A K. Petersen, C Gerbig, A Jordan, C Rodenbeck, M Rothe, Ronald Macatangay, J Norholt, O Schrems Jan 2010

Co-Located Column And In Situ Measurements Of Co2 In The Tropics Compared With Model Simulations, T Warneke, A K. Petersen, C Gerbig, A Jordan, C Rodenbeck, M Rothe, Ronald Macatangay, J Norholt, O Schrems

Faculty of Science - Papers (Archive)

The first ground-based remote sensing measurements of the column averaged volume mixing ratio of CO2 (XCO2) in tropical South America have been obtained at Paramaribo, Suriname (5.8 N, 55.2 W). The remote sensing observations are complemented by surface air-samples collected at the site, analyzed for CO2 and 13CO2. The surface in-situ measurements are strongly influenced by local sources. From the isotopic composition of the air samples the local source component is suggested to be dominated by the terrestrial biosphere. Using 13C from the NOAA/ESRL stations Ascension Is. (ASC), 7.9 S, 14.4W, and Ragged Point (RPB), 13.2 N, 59.4W, the data …