Reducing residual amplitude modulation in electro-optic phase modulators by erasing photorefractive scatter

Residual amplitude modulation (RAM) is an unwanted noise source in electro-optic phase modulators. The analysis presented shows that while the magnitude of the RAM produced by a MgO:LiNbO3 modulator increases with intensity, its associated phase becomes less well defined. This combination results in temporal fluctuations in RAM that increase with intensity. This behaviour is explained by the presented phenomenological model based on gradually evolving photorefractive scattering centres randomly distributed throughout the optically thick medium. This understanding is exploited to show that RAM can be reduced to below the 10-5 level by introducing an intense optical beam to erase the photorefractive scatter.

Gradual training of cascaded shape regression for facial landmark localization and pose estimation

Facial landmarks play an important role in face recognition. They serve different steps of the recognition such as pose estimation, face alignment, and local feature extraction. Recently, cascaded shape regression has been proposed to accurately locate facial landmarks. A large number of weak regressors are cascaded in a sequence to fit face shapes to the correct landmark locations. In this paper, we propose to improve the method by applying gradual training. With this training, the regressors are not directly aimed to the true locations. The sequence instead is divided into successive parts each of which is aimed to intermediate targets between the initial and the true locations. We also investigate the incorporation of pose information in the cascaded model. The aim is to find out whether the model can be directly used to estimate head pose. Experiments on the Annotated Facial Landmarks in the Wild database have shown that the proposed method is able to improve the localization and give accurate estimates of pose.

‘We don’t leave our identities at the city limits’ : Aboriginal and Torres Strait Islander people living in urban localities

Aboriginal and Torres Strait Islander people who live in cities and towns are often thought of as ‘less Indigenous’ than those who live ‘in the bush’, as though they were ‘fake’ Aboriginal people — while ‘real’ Aboriginal people live ‘on communities’ and ‘real’ Torres Strait Islander people live ‘on islands’. Yet more than 70 percent of Australia’s Indigenous peoples live in urban locations (ABS 2007), and urban living is just as much part of a reality for Aboriginal and Torres Strait Islander people as living in remote discrete communities. This paper examines the contradictions and struggles that Aboriginal and Torres Strait Islander people experience when living in urban environments. It looks at the symbols of place and space on display in the Australian cities of Melbourne and Brisbane to demonstrate how prevailing social, political and economic values are displayed. Symbols of place and space are never neutral, and this paper argues that they can either marginalise and oppress urban Aboriginal and Torres Strait Islander people, or demonstrate that they are included and engaged.

Using natural user interfaces for collaborative process modelling in virtual environments

Modelling business processes for analysis or redesign usually requires the collaboration of many stakeholders. These stakeholders may be spread across locations or even companies, making co-located collaboration costly and difficult to organize. Modern process modelling technologies support remote collaboration but lack support for visual cues used in co-located collaboration. Previously we presented a prototype 3D virtual world process modelling tool that supports a number of visual cues to facilitate remote collaborative process model creation and validation. However, the added complexity of having to navigate a virtual environment and using an avatar for communication made the tool difficult to use for novice users. We now present an evolved version of the technology that addresses these issues by providing natural user interfaces for non-verbal communication, navigation and model manipulation.

How much is that data in the window? Advertising your research data with QUT Library

Queensland University of Technology (QUT) Library offers a range of resources and services to researchers as part of their research support portfolio. This poster will present key features of two of the data management services offered by research support staff at QUT Library. The first service is QUT Research Data Finder (RDF), a product of the Australian National Data Service (ANDS) funded Metadata Stores project. RDF is a data registry (metadata repository) that aims to publicise datasets that are research outputs arising from completed QUT research projects. The second is a software and code registry, which is currently under development with the sole purpose of improving discovery of source code and software as QUT research outputs. RESEARCH DATA FINDER As an integrated metadata repository, Research Data Finder aligns with institutional sources of truth, such as QUT’s research administration system, ResearchMaster, as well as QUT’s Academic Profiles system to provide high quality data descriptions that increase awareness of, and access to, shareable research data. The repository and its workflows are designed to foster better data management practices, enhance opportunities for collaboration and research, promote cross-disciplinary research and maximise the impact of existing research data sets. SOFTWARE AND CODE REGISTRY The QUT Library software and code registry project stems from concerns amongst researchers with regards to development activities, storage, accessibility, discoverability and impact, sharing, copyright and IP ownership of software and code. As a result, the Library is developing a registry for code and software research outputs, which will use existing Research Data Finder architecture. The underpinning software for both registries is VIVO, open source software developed by Cornell University. The registry will use the Research Data Finder service instance of VIVO and will include a searchable interface, links to code/software locations and metadata feeds to Research Data Australia. Key benefits of the project include:improving the discoverability and reuse of QUT researchers’ code and software amongst QUT and the QUT research community; increasing the profile of QUT research outputs on a national level by providing a metadata feed to Research Data Australia, and; improving the metrics for access and reuse of code and software in the repository.

Let the children (and young people) play-where, how, why?

This paper reports on current research work with children and young people on the importance of public and private space for good health, wellbeing, social, educational and developmental outcomes. In many urban locations in Australia and elsewhere, public space is under attack from developers and attempts by authorities to control public space (Watson 2006). Private space in the home and garden-backyard is also under attack from development densification and trends towards bigger houses on smaller plots of land where gardens disappear altogether or a postage stamp remains (Gleeson and Sipe 2006). At the same time public policy advocates the benefits of outdoor exercise, set alongside fears about using public space exacerbated by notions of ‘stranger danger’ and control measures such as child and youth ‘curfews’. In this increasingly complex context, it is important to discover what children and young people value and need most in using private (home) and public space. In conjunction with the University of Otago, New Zealand, children and young people are consulted to discover how they use public space in parks and shopping centres and home space and the issues encountered and their proposals for improvement, to better inform policy debate, planning and formulation (ARACY 2009).

Very sensitive fiber Bragg grating accelerometer using transverse forces with an easy over-range protection and low cross axial sensitivity

The first fiber Bragg grating (FBG) accelerometer using direct transverse forces is demonstrated by fixing the FBG by its two ends and placing a transversely moving inertial object at its middle. It is very sensitive because a lightly stretched FBG is more sensitive to transverse forces than axial forces. Its resonant frequency and static sensitivity are analyzed by the classic spring-mass theory, assuming the axial force changes little. The experiments show that the theory can be modified for cases where the assumption does not hold. The resonant frequency can be modified by a linear relationship experimentally achieved, and the static sensitivity by an alternative method proposed. The principles of the over-range protection and low cross axial sensitivity are achieved by limiting the movement of the FBG and were validated experimentally. The sensitivities 1.333 and 0.634 nm/g were experimentally achieved by 5.29 and 2.83 gram inertial objects at 10 Hz from 0.1 to 0.4 g (g = 9.8 m/s 2), respectively, and their resonant frequencies were around 25 Hz. Their theoretical static sensitivities and resonant frequencies found by the modifications are 1.188 nm/g and 26.81 Hz for the 5.29 gram one and 0.784 nm/g and 29.04 Hz for the 2.83 gram one, respectively.

Shear-critical impact response of biaxially loaded reinforced concrete circular columns

A study on the vulnerability of biaxially loaded reinforced concrete (RC) circular columns in multi-story buildings under low- to medium-velocity impacts at shear-critical locations is presented. The study is based on a previously validated nonlinear explicit dynamic finite element (FE) modeling technique developed by the authors. The impact is simulated using force pulses generated from full-scale vehicle impact tests abundantly found in the literature with a view to quantifying the sensitivity of the design parameters of the RC columns under the typical impacts that are representative of the general vehicle population. The design parameters considered include the diameter and height of the column, the vertical steel ratio, the concrete grade, and the confinement effects. From the results of the simulations, empirical equations to quantify the critical impulses for the simplified design of the short, circular RC columns under the risk of shear-critical impacts are developed.

What are the offence and offender risk factors for Indigenous repeat drink drivers in Queensland?

In Australia and internationally, there is scant information about Indigenous repeat drink drivers. The aim was to identify the risk factors associated with repeat offending. De-identified data on drink driving convictions by offenders identifying as Indigenous in Queensland between 2006 and 2010 were examined. A range of univariate analyses were used to compare first time and repeat offenders on gender, age, court location and region (based on the accessibility/remoteness index of Australia), blood alcohol concentration and sentencing severity. Multivariate logistic regression adjusted for confounding variables. Convictions for repeat offenders were more likely from locations other than ‘major cities’ with the association strongest for courts in the ‘very remote’ region (OR=2.75, 2.06-3.76, p<.001). Indigenous offenders 40 years or older were found to be at reduced risk in comparison to offenders aged 15-24 years (OR=0.68, 0.54-0.86, p=0.01). After controlling for confounding factors, gender, sentencing severity and blood alcohol concentration levels were not significantly associated with recidivism. The association of recidivism and remoteness is consistent with higher rates of alcohol-related transport accidents involving Indigenous Australians in isolated areas. This study provides a platform for future research and allows for early attempts to address the need for intervention to reduce Indigenous drink driving recidivism.

Optical data encryption using time-dependent dynamics of refractive index changes in LiNbO3

We present a method for optical encryption of information, based on the time-dependent dynamics of writing and erasure of refractive index changes in a bulk lithium niobate medium. Information is written into the photorefractive crystal with a spatially amplitude modulated laser beam which when overexposed significantly degrades the stored data making it unrecognizable. We show that the degradation can be reversed and that a one-to-one relationship exists between the degradation and recovery rates. It is shown that this simple relationship can be used to determine the erasure time required for decrypting the scrambled index patterns. In addition, this method could be used as a straightforward general technique for determining characteristic writing and erasure rates in photorefractive media.

Stitching at the boundaries : Vietnamese garment industry workers in transnational spaces

This paper explores the interfaces between the transnational politics of labour and the experiences of Vietnamese women garment workers both in Vietnam and as migrants to other countries. As the global industries have come to organise much of the contemporary economic system, so too have they crossed national boundaries in search of cheap labour. At the same time enclaves of migrant disadvantage within the multi-ethnic nation-states of the developed world have also provided workers for the manufacture of clothing. In the case of Australia, these workers are mostly home-based and not in factories. In this paper I explore Vietnamese women's different incorporations into the garment industry in various locations – in Australia, in Vietnam, and in American Samoa. In so doing, I provide an analysis of the links between gender, global power relations and the contradictory space of transnational exchange.

Bending properties of Ag nanowires with pre-existing surface defects

Materials used in the engineering always contain imperfections or defects which significantly affect their performances. Based on the large-scale molecular dynamics simulation and the Euler–Bernoulli beam theory, the influence from different pre-existing surface defects on the bending properties of Ag nanowires (NWs) is studied in this paper. It is found that the nonlinear-elastic deformation, as well as the flexural rigidity of the NW is insensitive to different surface defects for the studied defects in this paper. On the contrary, an evident decrease of the yield strength is observed due to the existence of defects. In-depth inspection of the deformation process reveals that, at the onset of plastic deformation, dislocation embryos initiate from the locations of surface defects, and the plastic deformation is dominated by the nucleation and propagation of partial dislocations under the considered temperature. Particularly, the generation of stair-rod partial dislocations and Lomer–Cottrell lock are normally observed for both perfect and defected NWs. The generation of these structures has thwarted attempts of the NW to an early yielding, which leads to the phenomenon that more defects does not necessarily mean a lower critical force.

Person re-identification using group information

After first observing a person, the task of person re-identification involves recognising an individual at different locations across a network of cameras at a later time. Traditionally, this task has been performed by first extracting appearance features of an individual and then matching these features to the previous observation. However, identifying an individual based solely on appearance can be ambiguous, particularly when people wear similar clothing (i.e. people dressed in uniforms in sporting and school settings). This task is made more difficult when the resolution of the input image is small as is typically the case in multi-camera networks. To circumvent these issues, we need to use other contextual cues. In this paper, we use "group" information as our contextual feature to aid in the re-identification of a person, which is heavily motivated by the fact that people generally move together as a collective group. To encode group context, we learn a linear mapping function to assign each person to a "role" or position within the group structure. We then combine the appearance and group context cues using a weighted summation. We demonstrate how this improves performance of person re-identification in a sports environment over appearance based-features.

International acclaim : the role(s) of the international film festival in supporting emerging women’s cinema

International Film Festivals act as important sites for the exhibition of contemporary world cinema. Film festivals represent an increasingly transnational film culture, where audiences, filmmakers, distributors, press, critics and academics come together from all over the world to discover new films, network with one another and debate about the past, present and future of cinema. This research project investigates the role that international film festivals play within the wider international film industry, with a specific focus on emerging women filmmakers. It therefore explores the arena of contemporary women.s cinema at its intersection with the international film festival industry. The significance and original contribution of the research is its intervention in the growing field of film festival studies through a specific investigation of how international film festivals support emerging women filmmakers. The positioning of the research at the intersection of feminist film theory and festival research within the broader context of transnational cinema allows the examination of each festival, the attending filmmakers and their films to be addressed within a more refined and nuanced lens. A core method for the thesis is the close textual analysis of particular emerging women filmmakers. films which are screened at the respective festivals. The research also utilises the qualitative research strategies of the case study and the interview to ¡°seek to understand the context or setting of the participants through visiting this context and gathering information personally¡± (Creswell 2003, 9). The textual analysis is used in dialogue with the interviews and the participant observational data gathering to provide a related context for understanding these films and their cultural meanings, both personally for the filmmaker and transnationally across the festival circuit. The focus of the case studies is the Brisbane International Film Festival, the International Film Festival Rotterdam and the Toronto International Film Festival. These three festivals were chosen for their distinct geographical locations in the Asia Pacific, Europe and North America, as well as for their varying size and influence on the international film festival circuit. Specifically, I investigate the reasons behind why the organisers of a particular festival have chosen a certain woman.s film, how it is then packaged or displayed within the programme, and how all of this impacts on the filmmaker herself. The focus of my research is to investigate film festivals and their .real-life. applications and benefits for the filmmakers being supported, both through the exhibition of their films and through their attendance as festival guests. The research finds that the current generation of emerging women filmmakers has varying levels of experience and success at negotiating the international film festival circuit. Each of the three festivals examined include and promote the films of emerging women filmmakers through a range of strategies, such as specific programming strands dedicated to showcasing emerging talent, financial support through festival funds, providing visibility within the programme, exposure to international audiences and networking opportunities with industry professionals and other filmmakers. Furthermore, the films produced by the emerging women filmmakers revealed a strong focus on women.s perspectives and experiences, which were explored through the interweaving of particular aesthetic and cinematographic conventions.

Distributed low-power image processing in wireless sensor networks for intelligent video surveillance applications

Distributed Wireless Smart Camera (DWSC) network is a special type of Wireless Sensor Network (WSN) that processes captured images in a distributed manner. While image processing on DWSCs sees a great potential for growth, with its applications possessing a vast practical application domain such as security surveillance and health care, it suffers from tremendous constraints. In addition to the limitations of conventional WSNs, image processing on DWSCs requires more computational power, bandwidth and energy that presents significant challenges for large scale deployments. This dissertation has developed a number of algorithms that are highly scalable, portable, energy efficient and performance efficient, with considerations of practical constraints imposed by the hardware and the nature of WSN. More specifically, these algorithms tackle the problems of multi-object tracking and localisation in distributed wireless smart camera net- works and optimal camera configuration determination. Addressing the first problem of multi-object tracking and localisation requires solving a large array of sub-problems. The sub-problems that are discussed in this dissertation are calibration of internal parameters, multi-camera calibration for localisation and object handover for tracking. These topics have been covered extensively in computer vision literatures, however new algorithms must be invented to accommodate the various constraints introduced and required by the DWSC platform. A technique has been developed for the automatic calibration of low-cost cameras which are assumed to be restricted in their freedom of movement to either pan or tilt movements. Camera internal parameters, including focal length, principal point, lens distortion parameter and the angle and axis of rotation, can be recovered from a minimum set of two images of the camera, provided that the axis of rotation between the two images goes through the camera's optical centre and is parallel to either the vertical (panning) or horizontal (tilting) axis of the image. For object localisation, a novel approach has been developed for the calibration of a network of non-overlapping DWSCs in terms of their ground plane homographies, which can then be used for localising objects. In the proposed approach, a robot travels through the camera network while updating its position in a global coordinate frame, which it broadcasts to the cameras. The cameras use this, along with the image plane location of the robot, to compute a mapping from their image planes to the global coordinate frame. This is combined with an occupancy map generated by the robot during the mapping process to localised objects moving within the network. In addition, to deal with the problem of object handover between DWSCs of non-overlapping fields of view, a highly-scalable, distributed protocol has been designed. Cameras that follow the proposed protocol transmit object descriptions to a selected set of neighbours that are determined using a predictive forwarding strategy. The received descriptions are then matched at the subsequent camera on the object's path using a probability maximisation process with locally generated descriptions. The second problem of camera placement emerges naturally when these pervasive devices are put into real use. The locations, orientations, lens types etc. of the cameras must be chosen in a way that the utility of the network is maximised (e.g. maximum coverage) while user requirements are met. To deal with this, a statistical formulation of the problem of determining optimal camera configurations has been introduced and a Trans-Dimensional Simulated Annealing (TDSA) algorithm has been proposed to effectively solve the problem.