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A Prototype Of Autonomous Intelligent Surveillance Cameras, Wanqing Li, Igor Kharitonenko, S. Lichman, C. Weerasinghe
A Prototype Of Autonomous Intelligent Surveillance Cameras, Wanqing Li, Igor Kharitonenko, S. Lichman, C. Weerasinghe
Faculty of Informatics - Papers (Archive)
This paper presents an architecture and an FPGAbased prototype of an autonomous intelligent video surveillance camera. The camera takes the advantage of high resolution of CMOS image sensors and enables instantly automatic pan, tilt and zoom adjustment based upon motion activity. It performs automated scene analysis and provides immediate response to suspicious events by optimizing camera capturing parameters. The video output of the camera can be optimized to any region of interest while the camera continues to monitor the entire scene. Field trials of the prototyped camera have verified the proposed architecture.
Communications Breakdown: Revisiting The Question Of Information And Its Significance For Community Informatics Projects, William Tibben
Communications Breakdown: Revisiting The Question Of Information And Its Significance For Community Informatics Projects, William Tibben
Faculty of Informatics - Papers (Archive)
The gap between those who understand the complexities of community requirements and the information technologists who can build the technologies represents a central focus of concern with Community Informatics (CI) research. This paper explores how different assumptions about the utility of information leads to poor communication between researchers and practitioners. Braman’s four-part hierarchy is a useful vehicle to investigate this as she seeks to include a range of actors such as policy makers, technologists and community members. A number of case study examples are explored to illustrate the value of Braman’s work for CI.
A Variable Length Linear Array For Smart Antenna Systems Using Partial Optimization, W. Raad, Ian S. Burnett
A Variable Length Linear Array For Smart Antenna Systems Using Partial Optimization, W. Raad, Ian S. Burnett
Faculty of Informatics - Papers (Archive)
Adaptive arrays have been used extensively in wireless communications applications to reduce interference between desired users and interfering signals. Significant research has been directed at the uniform linear array (ULA), however, generally a fixed array length is used. In a mobile environment this has the disadvantage of producing a fixed beamwidth due to the fixed array lengths. The variable linear array (VLA) algorithm is a proposed algorithm that allows the beamwidth to be varied by activating and deactivating elements depending on the interferers present. This approach uses the LMS algorithm for adaptation, in an embedded system this could prove costly. …
Neuro-Fuzzy Admission Control In Cellular Networks, Raad Raad, Ibrahim Raad
Neuro-Fuzzy Admission Control In Cellular Networks, Raad Raad, Ibrahim Raad
Faculty of Informatics - Papers (Archive)
In this paper, a methodology is presented for designing an adaptive fuzzy logic controller based on neural networks. The neuro-fuzzy controller is first trained using data from an approximate analytical model of a cellular network then the controller is fine tuned and adapted to the unique cell dwell time and call holding time distributions of a particular cell in the network. Different cell dwell time distributions are considered for training the neuro-fuzzy controller. A neuro-fuzzy method that only relies on a limited amount of measured data for training purposes is also presented.
A New Spreading Matrix For Block Spread Ofdm, Ibrahim S. Raad, Xiaojing Huang, Raad Raad
A New Spreading Matrix For Block Spread Ofdm, Ibrahim S. Raad, Xiaojing Huang, Raad Raad
Faculty of Informatics - Papers (Archive)
This paper presents a new spreading matrix for block spread OFDM (BSOFDM) to improve the performance of the system by increasing the correlation between the symbols. This is achieved by rotating the modulation scheme used at the transmission, say QPSK, into a higher order modulation scheme, for example 16QAM. By this the correlation between the transmitted symbols is increased. The advantage of this new spreading matrix over more traditional spreading matrices is its flexibility in achieving different higher order modulation schemes during transmission depending on the angle alpha. This is compared to other spreading matrices in frequency selective channel environment.
Sharing Digital Rights With Domain Licensing, N. P. Sheppard, R. Safavi-Naini
Sharing Digital Rights With Domain Licensing, N. P. Sheppard, R. Safavi-Naini
Faculty of Informatics - Papers (Archive)
Sharing of multimedia content is a common practice that, combined with appropriate business models, need not be detrimental to the interests of content providers. Existing digital rights management systems, however, support only relatively limited sharing of content between multimedia terminals, resulting in inconvenience and frustration for end-users of rights-managed content. In this paper, we propose to combine the notion of an "authorised domain" with an "environment role" to permit end-users to share access to multimedia content within the constraints expressed in a domain licence. We describe how a variety of different business models can be supported using domain licences, and …
Adaptive Overlap-Add Equalization For Mb-Ofdm Ultra-Wideband, Darryn Lowe, Xiaojing Huang
Adaptive Overlap-Add Equalization For Mb-Ofdm Ultra-Wideband, Darryn Lowe, Xiaojing Huang
Faculty of Informatics - Papers (Archive)
A zero-pad can be used with orthogonal frequency division multiplexing (OFDM) for low-complexity robustness against multipath interference. In this paper, we use adaptive overlap-add (OLA) equalization for improvements of up to 0.6 dB improvement when used with multi-band OFDM (MB-OFDM) ultra-wideband in multipath channels. A theoretical model that relates the size of OLA window to post-equalizer signal-to-noise ratio is derived. An approximating algorithm is then developed that is suitable for low-complexity implementation, with Monte Carlo simulations used to quantify the performance improvements. We conclude that adaptive OLA equalization is computationally simple and can be implemented while remaining fully compliant with …
Ultra-Wideband Mb-Ofdm Channel Estimation With Complementary Codes, Darryn Lowe, Xiaojing Huang
Ultra-Wideband Mb-Ofdm Channel Estimation With Complementary Codes, Darryn Lowe, Xiaojing Huang
Faculty of Informatics - Papers (Archive)
In this paper, we design complementary codesets that significantly improve the quality of channel estimation in orthogonal frequency division multiplexing (OFDM) communication systems, with a focus on the recent MB-OFDM ultra-wideband (UWB) standard. The proposed time-domain OFDM channel estimation technique incurs only a nominal increase in computational complexity and is able to be readily retrofitted into the existing MB-OFDM standard. The underlying complementary codesets, found via an evolutionary algorithm, combine with the existing preamble synchronization sequences to yield asymptotically ideal auto-correlation functions (ACFs). We show how improvements exceeding 1 dB can be achieved in end-to-end packet error rate relative to …
A Novel Approach Of Spreading Spectrum In Ofdm Systems, Pingzhou Tu, Xiaojing Huang, Eryk Dutkiewicz
A Novel Approach Of Spreading Spectrum In Ofdm Systems, Pingzhou Tu, Xiaojing Huang, Eryk Dutkiewicz
Faculty of Informatics - Papers (Archive)
A method for spectrum spreading in an orthogonal frequency division multiplexing (OFDM) system is proposed in this paper, resulting in a spread spectrum OFDM (SS-OFDM) system suitable for ultra-wideband (UWB) applications. By modifying the IFFT module in a conventional OFDM transmitter and interleaving the modulated signal samples within an OFDM symbol, the transmitted signal spectrum is spread greatly to realize spread spectrum communications. This method of spectrum spreading is also compared with that of the multiband OFDM (MB-OFDM) system. The SS-OFDM signal has the characteristics of a white noise, and its power spectrum density is constant within the desired bandwidth. …
Effect Of Dc Offset On Ofdm System With Zero-Padded Suffix, Xiaojing Huang
Effect Of Dc Offset On Ofdm System With Zero-Padded Suffix, Xiaojing Huang
Faculty of Informatics - Papers (Archive)
The effect of direct current (DC) offset on orthogonal frequency division multiplexing (OFDM) system with zero-padded (ZP) suffix is analysed in this paper. It is found that the ZP appended OFDM system suffers more from DC offset than a cyclic prefix inserted OFDM system and even demonstrates bit error flooring if the DC power exceeds a maximum allowed threshold. Simple algorithms are also proposed for DC offset estimation and compensation. The analysis is confirmed by simulation using multiband OFDM specification for ultra-wideband application.
Adaptive Low-Complexity Mmse Channel Estimation For Ofdm, Darryn Lowe, Xiaojing Huang
Adaptive Low-Complexity Mmse Channel Estimation For Ofdm, Darryn Lowe, Xiaojing Huang
Faculty of Informatics - Papers (Archive)
In this paper we present extremely low-complexity adaptive infinite impulse response (IIR) filters that approximate minimum mean square error (MMSE) channel estimation in orthogonal frequency-division multiplexing (OFDM) systems. We show how the packet error rate (PER) can be significantly improved over conventional zero-forcing (ZF) estimation without incurring a significant increase in computational complexity. All quantitative results are provided in the context of multi-band OFDM (MB-OFDM) ultra-wideband (UWB) with standard IEEE channel models.
Low-Complexity Generation Of Scalable Complete Complementary Sets Of Sequences, Darryn Lowe, Xiaojing Huang
Low-Complexity Generation Of Scalable Complete Complementary Sets Of Sequences, Darryn Lowe, Xiaojing Huang
Faculty of Informatics - Papers (Archive)
This paper presents extremely low-complexity boolean logic for the generation of coefficients suitable for filtering or correlation of scalable complete complementary sets of sequences (SCCSS). As the unique auto- and cross-correlation properties of SCCSS are of broad interest, the simplicity of the proposed coefficient generation technique allows arbitrarily long SCCSS to be used in resource constrained applications.
Location-Based Services And The Privacy-Security Dichotomy, Katina Michael, L. Perusco, M G. Michael
Location-Based Services And The Privacy-Security Dichotomy, Katina Michael, L. Perusco, M G. Michael
Faculty of Informatics - Papers (Archive)
Location-based services (LBS) rely on knowledge of a user’s location to provide tailored services or information by means of a wireless device. LBS applications have wide-ranging implications for society, particularly in the context of tracking and monitoring groups of individuals such as children, invalids, and parolees. Despite a great deal of attention paid to technical and commercial aspects of LBS technologies, consideration of the legal, ethical, social and technology momentum issues involved has been wanting. This paper examines some of the more pressing issues that are expected to arise from the widespread use of LBS. The outcome of this paper …
Blind Separation Of Speech With A Switched Sparsity And Temporal Criteria, Daniel Smith, Ian Burnett
Blind Separation Of Speech With A Switched Sparsity And Temporal Criteria, Daniel Smith, Ian Burnett
Faculty of Informatics - Papers (Archive)
A blind signal separation algorithm (SCAtemp) that exploits both the sparse time-frequency representation and temporal structure of speech is proposed. SCAtemp compares each speech signal's adherence to the sparsity and temporal criteria, before switching to the most appropriate criteria to estimate each signal. This algorithm is shown to improve the real time separation performance of conventional BSS algorithms exclusively exploiting either the temporal structure, sparsity or statistical independence of signals. The improvement of SCAtemp over conventional BSS algorithms can be attributed to the use of additional a priori knowledge of speech in the temporal short term.
Synthesis Of Some Cyclic Indolic Peptoids As Potential Antibacterials, Vicki S. Au, John B. Bremner, Jonathan Coates, Paul A. Keller, Stephen G. Pyne
Synthesis Of Some Cyclic Indolic Peptoids As Potential Antibacterials, Vicki S. Au, John B. Bremner, Jonathan Coates, Paul A. Keller, Stephen G. Pyne
Faculty of Science - Papers (Archive)
The synthesis of cyclic peptoids containing an indole hydrophobic scaffold has been realised through the ring-closing metathesis of diallylated precursors. The precursors and their cyclic counterparts possessed poor antibacterial activity in contrast to previously reported cyclic peptoids containing hydrophobic scaffolds.
Classifying Surface Roughness With Ctfm Ultrasonic Sensing, Phillip J. Mckerrow, B. J. Kristiansen
Classifying Surface Roughness With Ctfm Ultrasonic Sensing, Phillip J. Mckerrow, B. J. Kristiansen
Faculty of Informatics - Papers (Archive)
Roughness is a characteristic of a surface that is a function of its geometry. Ultrasonic sensing in air provides range, area, and angle information because the surface geometry determines the characteristics of the echo. The authors introduce the “spatial-angle-filter model” to explain the impact of surface roughness on the echo. On the basis of this model, they design a set of features for use in classifying surfaces. The quality of the features and the classification is measured with the Mahalanobis distance. The resultant system is able to achieve 99.73% classification of a set of 12 surfaces using five features.
Viewpoints Merging Via Incrementally Elicited Ranked Structures, Aditya K. Ghose, Q. Lin
Viewpoints Merging Via Incrementally Elicited Ranked Structures, Aditya K. Ghose, Q. Lin
Faculty of Informatics - Papers (Archive)
Handling inconsistent requirements specifications remains a difficult challenge for the requirements engineering community. This paper seeks to apply techniques developed in the belief merging literature within AI to this problem. The application is non-trivial, since many belief merging operations cannot be directly applied, but must be modified to make them usable in practical settings. We address the problem of merging state model viewpoints, and improve on previous work by Chechik and Easterbrook. We develop a variant of the belief merging framework developed by Meyer et al, which we refer to as the framework of incrementally elicited ranked structures. We show …
Co-Evolution Of I* Models And 3apl Agents, Aneesh Krishna, Y. Guan, Aditya K. Ghose
Co-Evolution Of I* Models And 3apl Agents, Aneesh Krishna, Y. Guan, Aditya K. Ghose
Faculty of Informatics - Papers (Archive)
Agent-Oriented Conceptual Modelling (AOCM), as exemplified by the i* notation [9], represents an interesting approach to modelling early phase requirements that is particularly effective in capturing organisational contexts, stakeholder intentions and rationale. Our objective in this paper is to define means for executing i* models by translating these into set of interacting agents implemented in the 3APL language. We also propose a hybrid modelling, or co-evolution, approach in which i* models and 3APL agent programs are concurrently maintained and updated, while maintaining some modicum of loose coupling via consistency constraints. This paper explores how these two otherwise disparate approaches might …
Co-Evolution Of Agent Oriented Conceptual Models And Use Case Diagrams, Moshiur Bhuiyan, M. M. Zahidul Islam, Aneesh Krishna, Aditya K. Ghose
Co-Evolution Of Agent Oriented Conceptual Models And Use Case Diagrams, Moshiur Bhuiyan, M. M. Zahidul Islam, Aneesh Krishna, Aditya K. Ghose
Faculty of Informatics - Papers (Archive)
Agent--oriented conceptual modeling notations such as i* represents an interesting approach for modeling early phase requirements which includes organizational contexts, stakeholder intentions and rationale. On the other hand Use Case diagram is used for capturing functional requirements of the system. The integration of i* model and Use Case diagram closes the gap of capturing organizational requirements and system requirements. But in both contexts the requirements might change at any time. Any change made in one model must be reflected in the other. This paper proposes a methodology supporting the co-evolution of these two otherwise disparate approaches in a synergistic fashion.
On The Internal Structure Of Alpha-Mac, J. Huang, Jennifer Seberry, Willy Susilo
On The Internal Structure Of Alpha-Mac, J. Huang, Jennifer Seberry, Willy Susilo
Faculty of Informatics - Papers (Archive)
ALPHA-MAC is a MAC function which uses the building blocks of AES. This paper studies the internal structure of this new design. First, we provide a method to find second preimages based on the assumption that a key or an intermediate value is known. The proposed searching algorithm exploits the algebraic properties of the underlying block cipher and needs to solve eight groups of linear functions to find a second preimage. Second, we show that our idea can also be used to find internal collisions under the same assumption. We do not make any claims that those findings in any …
The Avian Flu Tracker - A Location Service Proof Of Concept, Katina Michael, B. Stroh, O. Berry, A. Muhlbauer, T. Nicholls
The Avian Flu Tracker - A Location Service Proof Of Concept, Katina Michael, B. Stroh, O. Berry, A. Muhlbauer, T. Nicholls
Faculty of Informatics - Papers (Archive)
The bird infecting viral strain H5N1, commonly known as the Avian Flu, is a highly infectious and resilient virus that can be fatal if contracted by humans. Authorities and health services have a major responsibility to citizens to respond quickly to minimize the possibility of a localized outbreak becoming a pandemic. The Avian Flu Tracker is a dynamic Location Based Service (LBS) designed to warn citizens of their proximity to potentially infectious regions. The system tracks the location of infected zones, dynamically estimating the spread of an uncontained area over time. Users subscribed to the service receive SMS messages alerting …
A Minimal Critical Set Of A Class Of Youden Squares, L. Fitina, Ken Russell, Jennifer Seberry
A Minimal Critical Set Of A Class Of Youden Squares, L. Fitina, Ken Russell, Jennifer Seberry
Faculty of Informatics - Papers (Archive)
We consider the Youden square formed by deleting one row of a v x v back-circulant Latin square and establish a critical set that contains a number of elements which is equal to v2/4 (v even) or (v2 — 1)/4 (v odd). We show that this critical set is minimal, for v even.
The Maintenance Of High Affinity Plasminogen Binding By Group A Streptococcal Plasminogen-Binding M-Like Protein Is Mediated By Arginine And Histidine Residues Within The A1 And A2 Repeat Domains., Martina L. Sanderson-Smith, Mark J. Walker, Marie Ranson
The Maintenance Of High Affinity Plasminogen Binding By Group A Streptococcal Plasminogen-Binding M-Like Protein Is Mediated By Arginine And Histidine Residues Within The A1 And A2 Repeat Domains., Martina L. Sanderson-Smith, Mark J. Walker, Marie Ranson
Faculty of Science - Papers (Archive)
Subversion of the plasminogen activation system is implicated in the virulence of group A streptococci (GAS). GAS displays receptors for the human zymogen plasminogen on the cell surface, one of which is the plasminogen-binding group A streptococcal M-like protein (PAM). The plasminogen binding domain of PAM is highly variable, and this variation has been linked to host selective immune pressure. Site-directed mutagenesis of full-length PAM protein from an invasive GAS isolate was undertaken to assess the contribution of residues in the a1 and a2 repeat domains to plasminogen binding function. Mutagenesis to alanine of key plasminogen binding lysine residues in …
Expressing Business Process Model As Owl-S Ontologies, M. A. Aslam, S. Auer, J. Shen, M. Herrmann
Expressing Business Process Model As Owl-S Ontologies, M. A. Aslam, S. Auer, J. Shen, M. Herrmann
Faculty of Informatics - Papers (Archive)
BPEL4WS is a well-established business process standard that can be used to orchestrate service-based workflows. However, the rapid growth and automation demands of e-business and grid applications require BPEL4WS to provide enhanced semantic annotations to achieve the goal of business processes automation. Here, OWL-S (OWL for Web Services) is designed to represent such kind of semantic information. Furthermore, there exists a similarity in the conceptual model of OWL-S and BPEL4WS that can be employed to overcome the lack of semantics in BPEL4WS by mapping the BPEL4WS process model to the OWL-S suite of ontologies. The mapped OWL-S service can be …
Swindew-A P2p-Based Decentralized Workflow Management System, Jun Yan, Y. Yang, G. K. Raikundalia
Swindew-A P2p-Based Decentralized Workflow Management System, Jun Yan, Y. Yang, G. K. Raikundalia
Faculty of Informatics - Papers (Archive)
Workflow technology undoubtedly has been one of the most important domains of interest over the past decades, from both research and practice perspectives. However, problems such as potential poor performance, lack of reliability, limited scalability, insufficient user support, and unsatisfactory system openness are largely ignored. This research reveals that these problems are mainly caused by the mismatch between application nature, i.e., distributed, and system design, i.e., centralized management. Therefore, conventional approaches based on the client-server architecture have not addressed them properly so far. The authors abandon the dominating client-server architecture in supporting workflow because of its inherent limitations. Instead, the …
Using Constraint Hierarchies To Support Qos-Guided Service Composition, Ying Guan, Aditya K. Ghose, Zheng Lu
Using Constraint Hierarchies To Support Qos-Guided Service Composition, Ying Guan, Aditya K. Ghose, Zheng Lu
Faculty of Informatics - Papers (Archive)
A key impediment to the widespread adoption of web services is the is the relatively limited set of tools available to deal with Quality-of-Service (QoS) factors [12]. QoS factors pose several difficult challenges in how they may be articulated. While the functional requirements of a service can be represented as predicates to be satisfied by the target system, QoS factors are effectively statements of objectives to be maximized or minimized. QoS requirements occur naturally as local specifications of preference. Dealing with QoS factors is therefore a multi-objective optimization problem. In effect, these objectives are never fully satisfied, but satisficed to …
Using Assumptions In Service Composition Context, Z. Lu, Aditya K. Ghose, P. Hyland, Y. Guan
Using Assumptions In Service Composition Context, Z. Lu, Aditya K. Ghose, P. Hyland, Y. Guan
Faculty of Informatics - Papers (Archive)
Service composition aims to provide the efficient and accurate model of a service, based on which the global service oriented architecture (SOA) can be realized, allowing the value-added services to be generated on the fly. Because of distributed responsibilities, ownership, and control, often, it is not feasible to acquire all information needed for the service composition, thus there might be no guarantee that the service execution has an anticipated effect. In this paper, we are going to extend current Semantic Web Service Description by introducing the concept of "Service Assumption" which allows reasoning with incomplete information. Furthermore, together with the …
Fundamental And Biotechnological Applications Of Neutron Scattering Measurements For Macromolecular Dynamics, M. Tehei, R. Daniel, G. Zaccai
Fundamental And Biotechnological Applications Of Neutron Scattering Measurements For Macromolecular Dynamics, M. Tehei, R. Daniel, G. Zaccai
Faculty of Science - Papers (Archive)
To explore macromolecular dynamics on the picosecond timescale, we used neutron spectroscopy. First, molecular dynamics were analyzed for the hyperthermophile malate dehydrogenase from Methanococcus jannaschii and a mesophilic homologue, the lactate dehydrogenase from Oryctolagus cunniculus muscle. Hyperthermophiles have elaborate molecular mechanisms of adaptation to extremely high temperature. Using a novel elastic neutron scattering approach that provides independent measurements of the global flexibility and of the structural resilience (rigidity), we have demonstrated that macromolecular dynamics represents one of these molecular mechanisms of thermoadaptation. The flexibilities were found to be similar for both enzymes at their optimal activity temperature and the resilience …
International Assessments Of The Vulnerability Of The Coastal Zone To Climate Change, Including An Australian Perspective, P. A. Abuodha, C. D. Woodroffe
International Assessments Of The Vulnerability Of The Coastal Zone To Climate Change, Including An Australian Perspective, P. A. Abuodha, C. D. Woodroffe
Faculty of Science - Papers (Archive)
Australia, and considers global, and in some cases national, assessments of vulnerability to climate change to evaluate the implications for the Australian coast, or to assess the applicability of particular approaches and methods to Australia. Climate change vulnerability assessment aims at assisting policymakers in adequately responding to the challenge of climate change by investigating how projected changes in the Earth's climate may affect natural systems and human activities. Generally studies consider, exposure or susceptibility of natural coastal systems, the effect on socio-economic systems (“impact assessment”), and/or how human actions may reduce adverse effects of climate change on those systems or …
A Fast Algorithm For Color Image Segmentation, L. Dong, P. Ogunbona, Wanqing Li, G. Yu, L. Fan, G. Zheng
A Fast Algorithm For Color Image Segmentation, L. Dong, P. Ogunbona, Wanqing Li, G. Yu, L. Fan, G. Zheng
Faculty of Informatics - Papers (Archive)
Based on K-means and a two-layer pyramid structure, a fast algorithm is proposed for color image segmentation. The algorithm employs two strategies. Firstly, a two-layer structure of a color image is established. Then, an improved K-means with integer based lookup table implementation is applied to each layer. The clustering result on the upper layer (lower resolution) is used to guide the clustering in the lower layer (higher resolution). Experiments have shown that the proposed algorithm is significantly faster than the original K-means algorithm while producing comparable segmentation results.