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This record contains a PhD dissertation and 4 short videos (visualisation demonstrations). Thesis (PhD(Computer and Information Science))--University of South Australia, 2017. Includes bibliographical references (pages 419-440) This dissertation presents a novel contribution to the field of augmented reality information visualisation - Situated Analytics. This dissertation proposed and evaluated situated analytics, merging augmented reality and visual analytics. Situated Analytics provides users with analytical reasoning tools for augmented reality information visualisation, involving users in the data investigation process. Situated and abstract visualisation techniques were developed based on the situated analytics requirements and limitations, to reduce visual cluttering, and to enhance the information accessibility. Two visual representation approaches were demonstrated through this research: visual cue and visual blending. Visual cues use annotations and graphical cues for information visualisation. Visual blending merges virtual content into the real scene to reduce the visual cluttering and to enhance the perception of information. This dissertation also presents novel blended interaction techniques for Situated Analytics. The developed techniques allow users to interact with physical objects and their associated data analytically. Panopto/Science, Mathematics & Computing

Thesis (PhD(Computer and Information Science))--University of South Australia, 2017. Includes bibliographical references (pages 103-118) Nervous systems are extraordinarily complex. This complexity gives rise to their ability to sense and process information and survive in the world. The down side of this complexity is that many disorders such as Alzheimer’s disease, multiple sclerosis, depression,schizophrenia, stroke and problems with hearing and vision can arise. One of the techniques used in studying both healthy and diseased nervous systems is computational modeling (Dayan and Abbott; 2001). In this thesis, we have studied two topics in which computational modeling may help in the treatment or diagnosis of neural disorders and for understanding their underlying causes.

Thesis (PhD(Mathematics))--University of South Australia, 2017. Includes bibliographical references (pages 285-314) Heatwaves are responsible for more deaths in Australia than all other natural hazards combined. As the frequency and intensity of heatwaves are growing, strategies to improve our resilience are becoming more vital. The different impacts of heatwaves, such as excess morbidity, electricity demand and water consumption, have previously been investigated in isolation. The various elements of heat stress resilience, including adaptation, vulnerability and the built environment, have not been explored together in connection with the associated negative impacts. A comprehensive assessment of the relationship between the negative impacts and the elements of heat stress resilience could increase our resilience against heatwaves. This research devised a novel framework for the assessment of heat stress risk and resilience, explored the drivers for and barriers to resilience, and analysed the differences between heat stress-resistant and energy-efficient building design.

Thesis (PhD(Computer and Information Science))--University of South Australia, 2017. Includes bibliographical references (pages 98-108) The aim of this study was to develop a three-stage mobile forensic visualisation lifecycle which would provide forensic practitioners with the ability to incorporate multiple or large datasets into a centralised database, allowing for improved analysis by implementing beneficial visualisation methodologies. Six criteria have been identified for validating the usability of new visualisation methodologies: repeatability, lucidity,anomaly, timeline view, filterable, granularity.

This paper is based on classroom observations from Norway with 7-8 years old children working on geometrical shapes. The intention is that the children shall classify different polygons according to their number of edges. The observations are part of a teaching sequence that is designed using principles from Brousseau’s Theory of Didactical Situations (TDS). From the teaching sequence we identify certain challenges in the children’s development of scientific terms and the observations allow us to conclude that these challenges to some extent are connected to specific semantic features of the Norwegian language. The use of TDS is instrumental in revealing the challenges that occurred and explaining what was changed to overcome them. Published by European Society for Research in Mathematics Education. Copyright the authors 2017.

Thesis (PhD(Mathematics))--University of South Australia, 2017. Includes bibliographical references (pages 199-226) This thesis develops methods for creating renewable energy data with realistic variations at high temporal and spatial resolutions, with sufficient accuracy for detailed system design. We address the need for solar irradiance data with high temporal resolution by developing a method for generating synthetic five-minute pairs of global horizontal irradiance (GHI) and direct normal irradiance (DNI), interpolated from hourly mean values. Our method can be applied to locations where only hourly data is available.

Thesis (PhD(Computer and Information Science))--University of South Australia, 2017. Includes bibliographical references (pages 168-183) In the past decades, causal discovery from observational data has been studied widely. However, most existing research has focused on detecting causal relationship between a single factor and the outcome, which may not be sufficient for reasoning about the cause of a particular effect. In this thesis, we study complex causal relationships with multiple factors involved, and have developed the methods for discovering combined causes, cause interactions and context specific causes from data. We have also developed a causality based classification model for predictions with causal interpretations.

Thesis (PhD(Computer and Information Science))--University of South Australia, 2017. Includes bibliographical references (pages 202-250) The primary goal of this thesis is to investigate information privacy attitudes and behaviours in online social networking (OSN). Diversity in perception, evaluation and protection of information privacy necessitates enhanced multidisciplinary research that utilises knowledge beyond a single discipline; it is unlikely that a discipline-specific approach would be particularly effective in explaining how OSN users perceive and protect their privacy. This thesis, therefore, examines information privacy through an interdisciplinary theoretical lens. Both qualitative and quantitative research methods and a variety of statistical techniques are used.

With the application of IOT technology in maize disease images for monitoring and collecting, timely detection of the types and characteristics of identification of disease has become a hot research in the diagnosis and treatment of diseases and insect pests. In order to improve the recognition accuracy of maize leaf, achieve rapid diagnostic purposes, this paper takes the leaf spot of maize gray leaf spot and image as the research object, use the computer image processing technology is studied on the effective segmentation and recognition of color and shape features. The genetic algorithm was adopted to optimize the selection of maize disease images real-time filtering; \( 3 * 3 \) mode noise suppression of the image selected by value smoothing; then select the HSV component of the color feature extraction of the disease; the maximum between class variance (OTSU) disease shape character segmentation and recognition. The results show that, based on genetic algorithm optimization based on image In HSV and Otsu method can be more accurate segmentation and recognition of the disease of color and shape features, and enhance the real-time and accuracy of the image of maize disease detection and recognition and oriented under the condition of things plant diseases and insect pests of maize and provide technical support.

T cell responses are guided by cytokines that induce transcriptional regulators, which ultimately control differentiation of effector and memory T cells. However, it is unknown how the activities of these molecular regulators are coordinated and integrated during the differentiation process. Using genetic approaches and transcriptional profiling of antigen-specific CD8(+) T cells, we reveal a common program of effector differentiation that is regulated by IL-2 and IL-12 signaling and the combined activities of the transcriptional regulators Blimp-1 and T-bet. The loss of both T-bet and Blimp-1 leads to abrogated cytotoxic function and ectopic IL-17 production in CD8(+) T cells. Overall, our data reveal two major overlapping pathways of effector differentiation governed by the availability of Blimp-1 and T-bet and suggest a model for cytokine-induced transcriptional changes that combine, quantitatively and qualitatively, to promote robust effector CD8(+) T cell differentiation.

International audience; We consider the problem of exploring an anonymous line by a team of k identical, oblivious, asynchronous deterministic mobile robots that can view the environment but cannot communicate. We completely characterize sizes of teams of robots capable of exploring a n-node line. For k= 5, or k=4 and n is odd. For all values of k for which exploration is possible, we give an exploration algorithm. For all others, we prove an impossibility result.

Thesis (PhD(Computer and Inf Science))--University of South Australia, 2016. Includes bibliographical references (pages 155-179) Cloud computing is increasingly adopted by both individual and organisational users;thus, ensuring the security and privacy of data stored in the cloud is a crucial requirement in an organisation‘s business continuity and risk assessment strategies. An incident handling strategy is key to mitigating risks to the confidentiality, integrity and availability of information assets, particularly those outsourced to the cloud located in one or more different countries. Thus, organisational cloud users may face challenges or be limited in their capability to handle security incidents (e.g. security breaches) on their sites since the infrastructure on which the data resides belongs to the cloud providers.

Thesis (PhD(Statistics))--University of South Australia, 2016. Includes bibliographical references (pages 165-170) In this thesis we study the VAR(1) [vector autoregressive] times series modulated by hidden Markov and hidden semi-Markov processes. These are examples of the so-called regime switching time series models. For the semi-Markov case, the time duration of the regimes can be arbitrarily distributed.

Thesis (PhD(Industry Doctoral Training Centre))--University of South Australia, 2016. Includes bibliographical references (pages 173-202) Plant phenotypic analysis, based on images captured as a function of plant variety, plant growth conditions and time, can offer useful information on the function of plant genes and the response of plants to environmental stresses. However, the majority of methods currently available to analyse these images are insufficient to fully utilise the large quantity of information available in the vast amount of images that can be captured. Correspondingly, the methods lag behind the ability of plant geneticists to generate novel varieties. Many image analysis methods are semi-automatic at best, with the accuracy of the segmentation step alone being an ongoing issue.

Thesis (PhD(Computer and Information Science))--University of South Australia, 2016. Includes bibliographical references (pages 180-186) This research presents several solutions to implement a scalable, efficient and secure solution, which adapts the widely used Session Initiation Protocol (SIP) over MANETs. These implementations make use of nomination algorithms and clusters to improve scalability and stability considering security factor for such implementation. Specifically, this research critically analyses existing VoIP and SIP services, particularly those relating to the potential deployment over MANETs; contributes to the design principles of SIP over MANETs; and develops and validates an adaptive, scalable and secure SIP solution for MANETs.

Thesis (PhD)--University of South Australia, 2016. Includes bibliographical references (pages 141-154). Data dependencies have undergone developments lately for improving data quality. Differential dependencies (DDs) are one such extensions based on the semantics of distance in data, useful in several data and data quality management applications.This doctoral dissertation investigates the discovery and extension of differential dependencies. The research is inspired by the usefulness of data dependencies in knowledge discovery, data management as well as data quality management applications in general; and particularly motivated by the powerful expressivity of DDs.

Thesis (PhD(Computer and Information Science))--University of South Australia, 2016. Includes bibliographical references (pages 172-202) Understanding the dynamics of human mobility behaviours has been a longstanding challenge since the seminal observations by Robert Brown in the19th century [54]. This dissertation, partitioned into two parts, has the prime goal of analysing human mobility data based on historical GPS trajectories in solving two interrelated problems. In the first part, the problem of human mobility prediction based on historical GPS trajectory data is tackled. The central theme of this problem is to forecast the anticipated future locations of individuals based on their historical mobility behaviours.

You recklessly told your boss that solving a non-linear system of size n ( n unknowns and n equations) requires a time proportional to n , as you were not very attentive during algorithmic complexity lectures. So now, you have only one night to solve a problem of big size (e.g., 1000 equations/unknowns), otherwise you will be fired in the next morning. The system is well-constrained and structurally irreducible: it does not contain any strictly smaller well-constrained subsystems. Its size is big, so the Newton-Raphson method is too slow and impractical. The most frustrating thing is that if you knew the values of a small number k ? n of key unknowns, then the system would be reducible to small square subsystems and easily solved. You wonder if it would be possible to exploit this reducibility, even without knowing the values of these few key unknowns. This article shows that it is indeed possible. This is done at the lowest level, at the linear algebra routines level, so that numerous solvers (Newton-Raphson, homotopy, and also p -adic methods relying on Hensel lifting) widely involved in geometric constraint solving and CAD applications can benefit from this decomposition with minor modifications. For instance, with k ? n key unknowns, the cost of a Newton iteration becomes O ( k n 2 ) instead of O ( n 3 ) . Several experiments showing a significant performance gain of our re-parameterization technique are reported in this paper to consolidate our theoretical findings and to motivate its practical usage for bigger systems. A new re-parameterization for reducing and unlocking irreducible geometric systems.No need for the values of the key unknowns and no limit on their number.Enabling the usage of decomposition methods on irreducible re-parameterized systems.Usage at the lowest linear Algebra level and significant performance improvement.Benefits for numerous solvers (Newton-Raphson, homotopy, p -adic methods, etc.)

Thesis (PhD(Computer and Inf Science))--University of South Australia, 2016. Includes bibliographical references (pages 201-231) Due to the popularity of Android devices and applications (apps), Android forensics is one of the most studied topics within mobile forensics. At the time of this research, there has been no academic publication or research on the forensic taxonomy of different categories of Android apps Therefore, taxonomies outlining artifacts of forensic interest and involving the use of different categories of Android apps will facilitate the timely collection and analysis of evidentiary materials from such apps. The focus of this thesis is to provide forensic practitioners and researchers with an in-depth understanding of artefacts that can be obtained in the forensic investigation of Android apps.

In the past decade the rise of Model-Driven Engineering has resulted in major changes to industrial software development. Using models for describing behaviours allows replacing part of the coding activities with higher-level definitions of concepts and behaviour: commonly cited as reducing costs, errors and time-to-market, while improving software quality and communication between stakeholders. However, we continue to see spectacular failures of large, expensive IT projects, often blamed on badly specified requirements. With high-level models of business environments—independent of technical considerations—now possible and standards like the Semantics of Business Vocabulary and Business Rules (SBVR) emphasising business and domain experts as the owners of their business requirements, we are reaching the point where formal modelling of requirements by the business experts themselves is necessary. However, requirements specifications written in natural language (e.g. English) still play a fundamental role in communicating the requirements. This thesis investigates an approach to semi-automatically transforming natural language specifications written by business/domain experts into formal models. The aim is to support the user in the process of formalising their requirements as models to reduce errors, ambiguities,inconsistencies, and the time taken. Thesis (PhD)--University of South Australia, 2016. Includes bibliographical references (pages 243-261)

Thesis (PhD(Computer and Inf Science))--University of South Australia, 2016. Includes bibliographical references (pages 157-173) This research investigates issues related to web applications such as mass-scale or targeted attacks aiming to steal, modify or delete confidential user data. These attacks have become increasingly popular with the adoption of cloud technologies. The main reasons behind such popularity include device interoperability and cost optimisations. Regardless of the reasons behind the choice, using cloud technology implies some loss of control over user-supplied data. The lack of control over private data and trust towards cloud providers caused a class of personally-hosted web applications to emerge. Choosing a self-hosted option, however, also requires provision of adequate protection for the data and, preferably, application users.

Thesis (PhD(Computer and Inf Science))--University of South Australia, 2016. Includes bibliographical references (pages 216-234) The contributions of the thesis are: (1) we coin the notion of COREs and develop three novel methods for discovering COREs; (2) we show the effectiveness of CCA as a ranking criterion; (3) we apply the methods to real-world biological datasets to find gene regulatory modules (which will help biologists with experi-ment design), and to bibliography datasets to get topic models.

Psychological disorders such as anxiety, depression and schizophrenia are, by nature, a reflection of dysfunctions in cognition; therefore, the accurate identification of normal cognitive activity in healthy brains may help in the understanding, diagnosis and treatment of such clinical impairments. Although various brain imaging techniques are available to aid researchers and clinicians in investigating and assessing cognitive function/dysfunction, electroencephalography (EEG) is better suited due to its wide- spread availability, non-invasiveness and millisecond temporal resolution. By recording the electrical activity of the brain from the scalp, EEG captures neural function in real- time and has been used extensively for well over half a century to diagnose neurological disorders as well as characterising various neuro-physiological and cognitive states. Thesis (PhD)--University of South Australia, 2016. Includes bibliographical references (pages 147-159).

Thesis (PhD(Computer and Information Science))--University of South Australia, 2016. Includes bibliographical references (pages 219-234) This thesis addresses a very important issue: the relationships between immigrants’ information behaviour and their settlement process. Specifically, it discusses Asian immigrants’ everyday life information seeking, information grounds and public library uses, and how these contribute to their settlement in South Australia.

Thesis (PhD(Mathematics))--University of South Australia, 2016. Includes bibliographical references (pages 296-321) This thesis contributes new knowledge in the areas of traffic emissions modelling and exposure mitigation, with a particular focus on enhancing the South Australian emissions modelling procedure to overcome the perceived limitations of CLEM.

Thesis (PhD)--University of South Australia, 2016. Includes bibliographical references (pages 144-151) This work investigates students' level of trust and dependency on Web search engine as an academic information resource, the level of result personalisation for academic queries, the effects of personalisation on students' satisfaction and engagement with Web search and finally, whether Web search and in particular personalisation influence students' opportunity to access information they seek.

Thesis (PhD(Electrical and Information Engineering))--University of South Australia, 2016. Includes bibliographical references (pages 198-210) The expectations of 21st-century missile guidance systems (also applies more broadly to unmanned vehicle systems) require that the weapon possess capabilities associated with autonomous learning and decision-making. These traits are usually associated with the notion of ‘intelligence’ as it is widely understood. This thesis is oriented towards this direction. It is scoped to help advance some of the knowledge associated with one aspect of achieving ‘Intelligent’ missile guidance, namely, to help with introducing automatic learning capability for upgrading traditional and modern missile guidance methods. The popular and widely applied multi-layer perceptron (MLP) has been selected as the technology to investigate in enabling traditional and modern missile guidance laws to incorporate automatic learning.

Thesis (PhD(Industry Doctoral Training Centre))--University of South Australia, 2016. Includes bibliographical references (pages 162-179) In this thesis three different transport models are presented, each contributing at a different level to the overall aim. First, to establish a baseline of understanding of transport behaviour, a model of passive ion and water transport in plant roots is described. Second, to understand what salt stress response behaviour is possible at the level of a single cell, a model of passive and active membrane transport of ions and water, across the tonoplast and plasma membranes of an individual plant cell, is formulated. This provided a wealth of information on the response of an isolated cell to salt stress and was a necessary step toward understanding organ level responses to salt stress. Finally, these two models were combined to produce a model of both active and passive transport of ions and water in a plant root, which was used to explore detailed aspects of the salt stress response of plant roots.

This paper investigates the widely linear processing (WLP) for the detection of circular signals, such as M-ary phase-shift keying (MPSK) signals and M-ary quadrature amplitude modulation (MQAM) signals. First, a unified mathematical model is derived to describe the conjugate symmetry of general MPSK/MQAM signals. In the unified model, a phase-rotation matrix (PRM) is introduced to partition the constellation of multiple-input multiple-output (MIMO) signals into subsets. Signals in a subset share the same PRM. Second, a widely linear receiver is proposed in each subset for MIMO detection. To avoid repetitive WLP in each subset, a widely linear sphere decoder (WLSD) is further proposed for MIMO systems. WLSD transforms the traditional sphere decoder (SD) searching for a true transmitted vector into a shrunk one by searching for the corresponding phase-rotation vector. Finally, the diversity order of WLSD is proven to be more than $N_R-\frac{N_T-1}{2}$ and less than $N_R$ , where $N_T$ (or $N_R$ ) denotes the number of transmitting (or receiving) antennas. Additional performance analysis is also conducted to quantify the signal-to-noise ratio improvement. The complexity analysis reveals that the candidate phase-rotation vectors of WLSD are no more than $(\frac{1}{2})^{N_T}$ of the SD candidates. Simulation results show that the proposed WLSD can achieve quasi-optimal bit error rate performance, while the computational complexity is reduced by more than a half compared with the Schnorr–Euchner sphere decoder.

Visuo-Haptic Augmented Reality (VHAR) systems enable users to see and touch digital information that is embedded in the real world with the help of sensors that acquire information about the environment and displays that augment the environment with computer-generated visual and haptic stimuli. An important goal of VHAR research is to build systems with low latency and minimal registration errors between vision and touch to improve realism and user performance. Applications that include fine-motor manipulation in domains such as medical procedures, training, assembly planning, or rapid prototyping benefit most from co-located VHAR user interfaces. This thesis presents a solution for precisely co-locating haptic feedback in AR, including a complete procedure for calibrating the temporal and spatial relations between all devices and a flexible framework for developing and evaluating VHAR applications. Thesis (PhD(Computer and Information Science))--University of South Australia, 2016. Includes bibliographical references (pages 125-137)

Thesis (PhD(Maths and Stats))--University of South Australia, 2016. Includes bibliographical references (pages 205-219) This system involves many parameters, such as the shape and geometry of the pores, the nature of the fluid (e.g., viscosity), the properties of the particles (e.g.,their size) and the form of the applied pressure which drives the motion of the fluid. In this thesis, we aim to gain a better understanding about the underlying processes affecting particle transport and also determine which are the important parameters of the system.

We consider the well known distributed setting of computational mobile entities, called robots, operating in the Euclidean plane in Look-Compute-Move (LCM) cycles. We investigate the computational impact of expanding the capabilities of the robots by endowing them with an externally visible memory register, called light, whose values, called colors, are persistent, that is they are not automatically reset at the end of each cycle. We refer to so endowed entities as luminous robots.We study the computational power of luminous robots with respect to the three main settings of activation and synchronization: fully-synchronous, semi-synchronous, and asynchronous. We establish several results. A main contribution is the constructive proof that asynchronous robots, illuminated with a constant number of colors, are strictly more powerful than traditional semi-synchronous robots.We also constructively prove that, for luminous robots, the difference between asynchrony and semi-synchrony disappears. This result must be contrasted with the strict dominance between the models without lights (even if the robots are enhanced with an unbounded amount of persistent internal memory).Additionally we show that there are problems that robots cannot solve without lights, even if they are fully-synchronous, but can be solved by asynchronous luminous robots with O ( 1 ) colors. It is still open whether or not asynchronous luminous robots with O ( 1 ) colors are more powerful than fully-synchronous robots without lights.We prove that this is indeed the case if the robots have the additional capability of remembering a single snapshot. This in turn shows that, for asynchronous robots, to have O ( 1 ) colors and a single snapshot renders them more powerful than to have an unlimited amount of persistent memory (including snapshots) but no lights.

Thesis (PhD(Telecommunications))--University of South Australia, 2016. Includes bibliographical references (pages 234-236) This thesis is comprised of a collection of nine peer-reviewed publications as well as one conventional chapter. The pivotal theme is performance optimization for multistatic target tracking and localization via waveform adaptation, geometry optimization, and pseudolinear estimation.

Thesis (PhD(Mathematics))--University of South Australia, 2016. Includes bibliographical references (pages 325-348) This research provides an evidence base for behavioural impacts of urban heat stress and highlights the vulnerability of public life to outdoor thermal discomfort. The thesis quantifies heat sensitivity of outdoor activities and provides appropriate measures to make public spaces of Australian cities more resilient to heat stress in the context of climate change. It also examines the prospect of having more heat resilient urban precincts in low-carbon cities. Triangulation methodology through a mix of quantitative and qualitative methods has been crafted for this research. An outdoor thermal discomfort pilot study revealed that the universal thermal comfort index (UTCI) represents the best- fit heat-activity model. Australia is likely to experience a 3.8˚C surface temperature increase (in the high emission RCP8.5 scenario) by 2090. Three Australian cities – Sydney, Melbourne, and Adelaide – are the larger urban context for case study public spaces.

Thesis (PhD)--University of South Australia, 2016. Includes bibliographical references (pages 275-298) Process-aware information systems have been employed in many enterprises and organisations as a means to optimise business operations. A crucial task in evolving such information systems is the management of process models. However, there is a significant gap between the desirable functionality of process model technology and what indeed is supported and offered by them. The contribution of this thesis is twofold. First, we propose an approach for configuration of process model abstractions with respect to a specific abstraction goal expressed as constraints on the abstraction relation and process transformation operators. Our framework goes beyond simple structural aggregation and uses domain-specific properties, taxonomies, meronymy, and flow criteria to generate a hierarchy of abstract process models. We outline the constraint-based framework;describe how rewriting-based abstraction mechanisms are embedded with consistency criteria guiding to find possible abstraction solutions, and show how notions of behaviour consistency can be utilised to obtain abstractions that conform to behavioural process inheritance criteria. Second, this research will focus on the co-evolution of process models and their implementations. It will use the notion of inheritance to restore consistency between process views that have been changed.

For a given point set, a particular point is called a star if it can see all the boundary points of the set. The star test determines whether a candidate point is a star for a given set. It is a key component of some topology computing algorithms such as Connected components via Interval Analysis (CIA), Homotopy type via Interval Analysis (HIA), etc. Those algorithms decompose the input object using axis-aligned boxes, so that each box is either not intersecting or intersecting with the object and in this later case its center is a star point of the intersection. Graphs or simplicial complexes describing the topology of the objects can be obtained by connecting these star points following different rules. The star test is performed for simple primitive geometric objects, because complex objects can be constructed using Constructive Solid Geometry (CSG), and the star property is preserved via union and intersection. In this paper, we improve the method to perform the test for implicit objects. For a primitive set defined by an implicit polynomial equation, the polynomial is made homogeneous with the introduction of an auxiliary variable, thus the degree of the star condition is reduced. A linear programming optimization is introduced to further improve the performance. Several examples are given to show the experimental results of our method. The work is supported by National Natural Science Foundation of China ( 61100084 , 61202197 , 61272300 ), Zhejiang Provincial Natural Science Foundation of China ( LQ13F020003 , LY15F020014 ), Zhejiang Province Department of Education Fund ( Y201223321 ), and China Scholarship Council . Scopus

Thesis (PhD(Computer and Information Science))--University of South Australia, 2016. Includes bibliographical references (pages 136-155) The current study explores the application of normalized transfer entropy (NTE) and nonlinear Granger Causality (GC) to detect and identify the patterns of information flow in the functional brain networks derived from EEG data during cognitive activity. Using a combination of signal processing, information and graph-theoretic techniques, this study has identified and characterized the changing connectivity patterns of the directed functional brain networks during different cognitive tasks.

Delivery of the Smart Grid is a topic of considerable interest within the power industry in general, and the IEEE specifically. This paper presents the smart grid landscape as seen by the IEEE Dielectrics and Electrical Insulation Society (DEIS) Technical Committee on Smart Grids. We define the various facets of smart grid technology, and present an examination of the impacts on dielectrics within power assets. Based on the trajectory of current research in the field, we identify the implications for asset owners and operators at both the device level and the systems level. The paper concludes by identifying areas of dielectrics and insulation research required to fully realize the smart grid concept. The work of the DEIS is fundamental to achieving the goals of a more active, self-managing grid.

International audience; Optical feedback interferometry (OFI) sensing is widely deployed in industrial and laboratory environments, due to its simple and low-cost optical setup compared to conventional interferometry techniques, in many sensing applications such as: the measurement of displacement, distance, velocity and vibration [1]. OFI signals can be acquired either through the observation of the power fluctuations with a monitoring photodiode implemented on the rear facet of the laser diode (PD signals) or by the amplification of the variations in the laser diode voltage (LV signals) [2]. In both methods, maximum signal-to-noise-ratio (SNR) should be maintained to achieve the best performance of the sensor. In this paper, we present a simple analytical model based on Lang and Kobayashi rate equations [3]. The model suggests a significant difference in injection current dependence of the strengths of the two interferometric signals. The PD signal is linearly dependent on injection current while the LV signal depends on the slope efficiency and the temperature. For an ideal laser diode, where slope efficiency is constant, the LV signal should remain constant. However, in practice slope efficiency decreases with the increase of injection current, as shown in Fig. 1a, due to thermal effects [4], resulting in the decrease of the LV signal with injection current.

International audience; Video dissemination to a group of vehicles is one of the many fundamental services envisioned for Vehicular Ad hoc Networks, especially as a building block for entertainment applications. For this purpose, in this paper we describe VoV, a video dissemination protocol that operates under extremely dynamic road traffic conditions. Contrary to most existing approaches that focus exclusively on always-connected networks and tackle the broadcast storm problem inherent to them, VoV is designed to operate under any kind of road traffic condition. We propose a new geographic-based broadcast suppression mechanism that gives a higher priority to rebroadcast to vehicles inside especial forwarding zones. Furthermore, vehicles store and carry received messages in a local buffer in order to forward them to vehicles that were not covered by the first dissemination process, probably as a result of collisions or intermittent disconnections. Finally, VoV employs a rate control mechanism that sets the pace at which messages must be transmitted according to the perceived network data traffic, thus avoiding channel overloading. Therefore, VoV adapts not only to the perceived road traffic condition, but also to the perceived channel quality. When compared to two related and well-accepted solutions–ABSM and AID–under Manhattan grid and real city scenarios, we show that, overall, our proposal is more efficient in terms of message delivery, delay and overhead.

International audience; We describe and evaluate a pre-processing method based on a periodic spiral sampling of diffusion-gradient directions for high angular resolution diffusion magnetic resonance imaging. Our pre-processing method incorporates prior knowledge about the acquired diffusion-weighted signal, facilitating noise reduction. Periodic spiral sampling of gradient direction encodings results in an acquired signal in each voxel that is pseudo-periodic with characteristics that allow separation of low-frequency signal from high frequency noise. Consequently, it enhances local reconstruction of the orientation distribution function used to define fiber tracks in the brain. Denoising with periodic spiral sampling was tested using synthetic data and in vivo human brain images. The level of improvement in signal-to-noise ratio and in the accuracy of local reconstruction of fiber tracks was significantly improved using our method.

Thesis (PhD)--University of South Australia, 2015. Includes bibliographical references (pages 165-179) This thesis considers the problem of hedging a European-style option on several assets in a market where asset prices have jump-diffusion dynamics. It is known that markets with jumps are incomplete in the sense that it is impossible to perfectly hedge against the payoff at maturity. In addition, there are infinitely many risk-neutral measures which one can use to price and hedge options.

Thesis (PhD)--University of South Australia, 2015. Includes bibliographical references (pages 143-160) Emerging patterns are patterns whose frequencies increase from one dataset to another. They can reveal useful trends and contrasts in datasets to support decision making such as trend prediction and classification. Discovering emerging patterns is however faced with challenges such as difficulty in early termination, and eliminating those that are redundant or due to random chance and data fluctuations. Additionally, current works mostly focus on their discovery for classification and seldom discuss their application in time-stamped datasets for trend prediction. In this thesis, to mine emerging and decaying patterns from time-stamped datasets that will support trend prediction, we firstly introduce a non-derivable interestingness measure in emerging pattern mining for discovering our defined non-derivable emerging and decaying patterns as those that are not redundant, and whose emergence or decay cannot be inferred. We also introduce a productiveness measure for discovering our defined productive emerging and decaying patterns as those encoding inherent item relationships but not due to random chance and data fluctuations. Subsequently,we introduce an effective trend prediction model for time-stamped datasets based on emerging and decaying patterns.

Thesis (PhD)--University of South Australia, 2015. Includes bibliographical references (pages 144-176) This research undertook a qualitative and quantitative exploratory analysis of information security management in Australian real estate industry from their perspectives and those of their customers. The main objectives of the research were to: firstly, examine the attitudes and concerns of real estate customers regarding information privacy when providing personal information. The research findings from the customer’s perspective can be summarised as follows: 1) Individuals are more concerned about the potential risks than the benefits that they may gain when providing personal information to a real estate organisation; 2) There is no difference between an open and a closed (i.e. high/low level of self-disclosure) individual regarding information privacy concerns when dealing with a real estate company; 3) The more a customer trusts a real estate organisation, the less concerned he/she will be about information privacy; and 4) Real estate customers who were more concerned about their privacy when they were online would be more likely to worry about their information remaining confidential.

Thesis (PhD)--University of South Australia, 2015. Includes bibliographical references (pages 312-345) The lack of an established framework is the main motivation of this thesis, which compelled investigating the answer to the research question: how can mobile collaboration technologies assist maintenance activities in engineering asset management organisations? With respect to the existing literature, this research aims to develop a unique framework that addresses three aspects, including the business process alignment at all three levels (strategic, tactical and operational) in company activities through the variable of mobile collaboration technologies that meet all maintenance collaboration requirements (technological, organisational and people perspectives).

Thesis (PhD)--University of South Australia, 2015. Includes bibliographical references (pages 245-262). Effective interaction devices and techniques are essential to the usability of a wearable computer system and can have a significant influence upon its adoption. In light of this,the exploration of wearable human-computer interaction is an important and necessary field of study. However, despite the need to better understand wearable interaction,there has been little work investigating the usability of input devices available in the market place suitable for use with wearable computers. Notably, there exists a gap in the literature pertaining to the evaluation of commercial pointing devices suitable for use with wearable computers where participants are evaluated while wearing a computer and a head-worn display (i.e. in a wearable context). This dissertation is positioned within the space of wearable human-computer interaction and presents contributions to the field motivated by the necessity to understand and quantify the commercially available pointing devices suitable for use with wearable computers.

Thesis (PhD)--University of South Australia, 2015. Includes bibliographical references (pages 184-200) Collaboration is necessary when a task is too complex and difficult to perform solitary. Many search situations demand people working together to solve a common goal. Tourism information searching is not an exception. Web searching has increasingly become a prevalent channel for tourists to conduct search for information. A group-based traveling information search activity includes preparing a travel plan, dividing the task among the group members, developing different strategies, seeking various information, exchanging views and ideas and decision-making. In addition to these features, communication among collaborators is also important. All these actions demand collaboration among the group members. However, despite its potential appeal and necessity, collaborative tourism information searching on the Web is under-explored. The nature and availability of tourism information and its role in our lives have changed significantly, but the methods and systems that are used to access and share that information in collaborative mode have remained mostly unchanged. This study aims to investigate tourists’ collaborative search behavior including collaborative search stages, search strategies, nature of information sharing, and problems encountered during collaborative search. This PhD thesis also attempts to develop a collaborative tourism information search tool.

Thesis (PhD(Computer and Information Science))--University of South Australia, 2015. Includes bibliographical references (pages 9.1-9.17) The overarching aim of this research is to provide an evidence based frame work to guide practitioners in the conduct of forensically sound cloud computing investigations. We propose a four-stage cloud forensic framework, which builds upon prevalent digital forensics frameworks by McKemmish (1999) and NIST (Kent et al.). ForFACTS: a Forensic Framework for Analysis of Cloud Technologies and Services (Page vi 2006). The stages are: ‘Evidence Source Identification and Preservation’,‘Collection’, ‘Examination and Analysis’ and ‘Reporting and Presentation’. These stages are designed to address specific forensic challenges in the cloud computing environment including, for example, the issues implicit in remote preservation and collection.

International audience; Widely linear processing (WLP) can provide attractive performance improvement in wireless communication systems. However, performance improvement brought by WLP is mainly achieved by exploiting signal's non-circularity, which leads to the fact that existing works on WLP are mainly confined to the cases related to non circular signals or improper signals with imbalanced I/Q components. In this paper, WLP for circular signals, such as PSK signals, is investigated by exploiting the hidden properties of PSK signals. The hidden properties of PSK signals are firstly studied, and a unified mathematical model is derived to describe the hidden properties of PSK signals. Furthermore, a widely linear sphere decoding (WLSD) algorithm exploiting PSK signals' hidden properties is proposed for MIMO systems. Compared to traditional sphere decoding (SD), WLSD has little performance loss, and it transforms the traditional SD searching for the true transmitted vector into the shrunk searching for the corresponding rotation vector, the candidate rotation vectors of WLSD are only ( 1 2 )NT of SD candidate vectors. Simulation results show that the proposed algorithm can achieve quasi-optimal BER performance, while the computational complexity is significantly reduced by more than a half compared with Schnorr-Euchner sphere decoder.

Background: Childhood mortality, particularly in the first 5 years of life, is a major global concern and the target of Millennium Development Goal 4. Although the majority of childhood deaths occur in Africa and Asia, these are also the regions where such deaths are least likely to be registered. The INDEPTH Network works to alleviate this problem by collating detailed individual data from defined Health and Demographic Surveillance sites. By registering deaths and carrying out verbal autopsies to determine cause of death across many such sites, using standardised methods, the Network seeks to generate population-based mortality statistics that are not otherwise available.Objective: To present a description of cause-specific mortality rates and fractions over the first 15 years of life as documented by INDEPTH Network sites in sub-Saharan Africa and south-east Asia.Design: All childhood deaths at INDEPTH sites are routinely registered and followed up with verbal autopsy (VA) interviews. For this study, VA archives were transformed into the WHO 2012 VA standard format and processed using the InterVA-4 model to assign cause of death. Routine surveillance data also provided person-time denominators for mortality rates. Cause-specific mortality rates and cause-specific mortality fractions are presented according to WHO 2012 VA cause groups for neonatal, infant, 1–4 year and 5–14 year age groups.Results: A total of 28,751 childhood deaths were documented during 4,387,824 person-years over 18 sites. Infant mortality ranged from 11 to 78 per 1,000 live births, with under-5 mortality from 15 to 152 per 1,000 live births. Sites in Vietnam and Kenya accounted for the lowest and highest mortality rates reported.Conclusions: Many children continue to die from relatively preventable causes, particularly in areas with high rates of malaria and HIV/AIDS. Neonatal mortality persists at relatively high, and perhaps sometimes under-documented, rates. External causes of death are a significant childhood problem in some settings.Keywords: Childhood; Africa; Asia; mortality; INDEPTH Network; verbal autopsy; InterVA(Published: 29 October 2014)Citation: Glob Health Action 2014, 7: 25363 - http://dx.doi.org/10.3402/gha.v7.25363SPECIAL ISSUE: This paper is part of the Special Issue: INDEPTH Network Cause-Specific Mortality. More papers from this issue can be found at http://www.globalhealthaction.net