Visual Patterns in the Perception of Abstract and Social Stimuli

This thesis investigated with regard to the perception of abstract and social stimuli: (1) What constitutes a visual pattern? (2) Whether people possess a proclivity towards one particular pattern type. (3) When is patterning imposed or detected by the visual system? The abstract stimuli consisted of checkerboard patterns and the social stimuli consisted of faces or social groups. Initially the term "pattern" was defined as an image that contains redundant information. This was illustrated by a bias when defining patterns by members of the public towards images that contain both repeated and reflective symmetry, or a low number of possible variants and therefore reduced information content, i. e. more redundancy. Similarly reflective symmetry was identified as a key property in defining faces. The effect of symmetry type on early visual processing was investigated further in a series of backward masking experiments on both abstract and facial stimuli (Chapters 6& 7). The results of the masking experiments suggest a bias during early visual processing for patterns that contain symmetry (i. e. repetition or reflection), or share common fate compared with randomly generated patterns or distorted faces. A top-hemifield and LVF bias was observed in the early detection of patterns. Patterns that take advantage of these properties such as the eyes within the face were suggested as having a perceptual advantage. Patterning appears to be imposed at all stages of visual processing. At early stages of visual processing, repetition (and in the face the eyes) was observed as having an early perceptual advantage over reflection (and in the face the mouth). However at later stages of processing repetition appeared to be processed serially and no longer had a perceptual advantage over reflection (ISIs >42ms). Reflection was suggested as having a perceptual advantage post V1 (ISIs >96ms). Patterning continues throughout a visual scene from the local level to the global level, as such both the human face and human social groups can be perceived as patterns. This was illustrated by a series of experiments investigating the effect of patterning on the perception of images presented in the periphery of a scene (Chapter 8)

Trust and Voice Biometric Authentication: Understanding the Levels of User’s Trust on Authentication Methods

Due to the singularity of the distinct biometric traits, biometric authentication factors have become increasingly prevalent in daily life and are predicted to target future authentication methods. Previous studies established that the human voice is one of the most natural, non-intrusive, and convenient behavioral biometric factors compared to other biometric authentication methods. Despite the non-intrusive characteristics of voice biometric authentication, it has been brought under scrutiny for many reasons, including the accuracy of biometric data, a general societal trust and distrust with technology and the risk of theft and imitation. Although, when it comes to trusting technology, users’ perceptions change with time through continued use of technology, and thus allowing perceptions and opinions to change. However, there are fundamental factors that can contribute to how users develop trust with technologies over time. This study derived a realistic trust evaluation model that incorporates security, privacy, safety, usability, reliability, and availability factors into a trust vector for a flexible measurement of trust in the user accessing the technology. Based on the derived trust model, we experiment using quantitative method whether the users are willing to trust voice biometric authentication method over PIN, fingerprint, and token-based authentication and hence would be inclined to adopt and utilize it as a means of user authentication to access technology. We applied the Kruskal-Wallis H test and the post-hoc test to understand which authentication method the user trusts, based on statistical significance and which groups were found to have that statistical difference. The result of the study suggests that users have less trust with voice compared to other authentication methods especially traditional means of knowledge-based authentication such as PIN’s which consistently ranked much higher than voice in pairwise comparisons

Early embryogenesis in pisum sativum L

The temporal and spatial patterns of differential legA expression during early Pisum embryogenesis have been examined. An in situ hybridisation protocol has been empirically refined to allow analysis of low level legA expression, at the mRNA level, whilst ELISA and immunocytochemistry have been used to examine both protein levels and spatial distribution within the early seed. Low levels of legK mRNA were detected in very early globular embryos which were present at 4-5 d.a.f. High levels of legK expression were detected in the transient endosperm tissue at both the mRNA and protein level. High levels of expression, at the mRNA level, were also detected within the suspensor, although a similar level of expression at the protein level was not detected. It is proposed that legA expression within both the endosperm and suspensor is of nutritional significance for the development of the embryo. Comparison of legA mRNA and protein localisation studies, at later stages of embryo development, demonstrated a very strong correlation, both quantitatively and spatially, between mRNA and protein levels, indicating the importance of transcription level regulation in the control of differential legA expression. A cDNA complementary to a mRNA species present at elevated levels in Pisum root was used to examine embryonic root (radicle) ontogeny. The mRNA species was found to be absent from embryonic root, however its presence in primary roots of seedlings four days post imbibition has been demonstrated

Octopus Senses: From Genes To Behavior

Octopuses are intelligent, soft-bodied animals, have complex nervous systems with remarkable cognitive abilities and keen senses that perform reliably in a variety of visual and chemo-tactile learning tasks for exploring and sensing the environment. They have the largest nervous system of any invertebrate, with 500 million neurons distributed centrally and peripherally throughout the body. The nervous system of common octopus (Octopus vulgaris), is comprised of central lobes surrounding the esophagus and a pair of optic lobes that together contain approximately a third of the neurons, with the remaining two-thirds distributed within the arms (e.g. in the large axial nerve cords that extends along the center of each of their eight arms). The most obvious characteristic feature of an octopus is its eight long and flexible arms, but these pose a great challenge for achieving the level of motor and sensory information processing necessary for their behaviors. In addition, octopuses have a significant number of lobes of the nervous system dedicated to visual, tactile, and chemosensory perception. In this study, I aimed to provide a comprehensive view on the genetic bases for the tactile form of olfaction, extraocular photoreception in the sucker, localization of photoreceptors molecules in the optic lobe of O. vulgaris, as well as to identify the major genes are involved in the adult neurogenesis and then the cognitive system in O. vulgaris. I have applied a developed whole-mount in situ hybridization, real-time qPCR, and bioinformatic methods, supported by behavioral evidences to provide a comprehensive view on these processes in O. vulgaris, highlight how genomic innovation translates into organismal organization novelties. Results achieved contributed to some extent, and promoted interest in this field

Engineering derivatives from biological systems for advanced aerospace applications

The present study consisted of a literature survey, a survey of researchers, and a workshop on bionics. These tasks produced an extensive annotated bibliography of bionics research (282 citations), a directory of bionics researchers, and a workshop report on specific bionics research topics applicable to space technology. These deliverables are included as Appendix A, Appendix B, and Section 5.0, respectively. To provide organization to this highly interdisciplinary field and to serve as a guide for interested researchers, we have also prepared a taxonomy or classification of the various subelements of natural engineering systems. Finally, we have synthesized the results of the various components of this study into a discussion of the most promising opportunities for accelerated research, seeking solutions which apply engineering principles from natural systems to advanced aerospace problems. A discussion of opportunities within the areas of materials, structures, sensors, information processing, robotics, autonomous systems, life support systems, and aeronautics is given. Following the conclusions are six discipline summaries that highlight the potential benefits of research in these areas for NASA's space technology programs

An Investigation into the Performance of Ethnicity Verification Between Humans and Machine Learning Algorithms

There has been a significant increase in the interest for the task of classifying demographic profiles i.e. race and ethnicity. Ethnicity is a significant human characteristic and applying facial image data for the discrimination of ethnicity is integral to face-related biometric systems. Given the diversity in the application of ethnicity-specific information such as face recognition and iris recognition, and the availability of image datasets for more commonly available human populations, i.e. Caucasian, African-American, Asians, and South-Asian Indians. A gap has been identified for the development of a system which analyses the full-face and its individual feature-components (eyes, nose and mouth), for the Pakistani ethnic group. An efficient system is proposed for the verification of the Pakistani ethnicity, which incorporates a two-tier (computer vs human) approach. Firstly, hand-crafted features were used to ascertain the descriptive nature of a frontal-image and facial profile, for the Pakistani ethnicity. A total of 26 facial landmarks were selected (16 frontal and 10 for the profile) and by incorporating 2 models for redundant information removal, and a linear classifier for the binary task. The experimental results concluded that the facial profile image of a Pakistani face is distinct amongst other ethnicities. However, the methodology consisted of limitations for example, low performance accuracy, the laborious nature of manual data i.e. facial landmark, annotation, and the small facial image dataset. To make the system more accurate and robust, Deep Learning models are employed for ethnicity classification. Various state-of-the-art Deep models are trained on a range of facial image conditions, i.e. full face and partial-face images, plus standalone feature components such as the nose and mouth. Since ethnicity is pertinent to the research, a novel facial image database entitled Pakistani Face Database (PFDB), was created using a criterion-specific selection process, to ensure assurance in each of the assigned class-memberships, i.e. Pakistani and Non-Pakistani. Comparative analysis between 6 Deep Learning models was carried out on augmented image datasets, and the analysis demonstrates that Deep Learning yields better performance accuracy compared to low-level features. The human phase of the ethnicity classification framework tested the discrimination ability of novice Pakistani and Non-Pakistani participants, using a computerised ethnicity task. The results suggest that humans are better at discriminating between Pakistani and Non-Pakistani full face images, relative to individual face-feature components (eyes, nose, mouth), struggling the most with the nose, when making judgements of ethnicity. To understand the effects of display conditions on ethnicity discrimination accuracy, two conditions were tested; (i) Two-Alternative Forced Choice (2-AFC) and (ii) Single image procedure. The results concluded that participants perform significantly better in trials where the target (Pakistani) image is shown alongside a distractor (Non-Pakistani) image. To conclude the proposed framework, directions for future study are suggested to advance the current understanding of image based ethnicity verification.Acumé Forensi

Exploiting Spatio-Temporal Coherence for Video Object Detection in Robotics

This paper proposes a method to enhance video object detection for indoor environments in robotics. Concretely, it exploits knowledge about the camera motion between frames to propagate previously detected objects to successive frames. The proposal is rooted in the concepts of planar homography to propose regions of interest where to find objects, and recursive Bayesian filtering to integrate observations over time. The proposal is evaluated on six virtual, indoor environments, accounting for the detection of nine object classes over a total of ∼ 7k frames. Results show that our proposal improves the recall and the F1-score by a factor of 1.41 and 1.27, respectively, as well as it achieves a significant reduction of the object categorization entropy (58.8%) when compared to a two-stage video object detection method used as baseline, at the cost of small time overheads (120 ms) and precision loss (0.92).</p

Quality of drinking and recreational water in the Hunter New England region of New South Wales: bridging the gap between research, practice and policy

Introduction Population health research may include primary data collection and analysis; analysis of existing data; and systematic reviews for problem definition, solution generation, and evaluation. The main objective of this thesis was to analyse routinely collected data and primary data to assess drinking and recreational water quality management in the Hunter New England region of New South Wales (NSW), Australia. This research was practitionerled and designed to bridge the gap between research and policy in drinking water management in NSW. When used with a specific research goal, routinely collected data obtained for performance monitoring purposes is an important tool for improving the quality of water supplies. Such practitioner-led research may be directly translated into local practice to improve public health service delivery. Continuous interactions between practitioner-researchers, academics, decision makers and other stakeholders throughout the research process provided impetus for evidence adoption through sustained evaluation of public health benefits. This thesis provides a firm foundation for the design of future environmental health interventions for the translation of research evidence to policy decision outcomes, leading to improved water quality and public health in rural areas. Setting In NSW, the NSW Public Health Act 2010 (NSW Government, 2010) regulates water suppliers to provide safe water to consumers. NSW Health provides drinking water supply protocols that include monitoring, reporting, and public notifications. The NSW Health's Drinking Water Monitoring Program provides free water testing for suppliers throughout the state. Public water suppliers (utilities) are allocated barcoded-labels for the recommended number of samples for each water supply system each year. Compliance is measured by the adequacy of sampling, in which at least 98% should yield no E. coli detections. The Program centrally manages the internet-based NSW Drinking Water Database, which has recorded more than 20 000 sample results per year since 2001. Therefore, there is sufficient routinely collected data to assess drinking water quality in NSW. Method A Participatory Action Research (PAR) process was applied using a mixed methods framework. The practitioner researcher's research and collaborations with academics, policy makers and stakeholders from the planning through to the implementation of projects ensured that expectations were clear. An 'adopt and intervene as-we-go' philosophy was applied. The evidence was interrogated and areas of intervention were applied. Further projects were then designed to evaluate the identified areas of intervention. Four approaches were taken to explore and bring about change in drinking water quality management through advocacy: • Working with departmental staff to analyse routinely collected microbiological water quality data for reticulated water supplies to improve drinking water quality management within existing work budgets; • Working with recreational parks authorities to collect and analyse data to assess and improve private drinking water management; • Working with an Aboriginal community to assess reticulated drinking water supply quality and acceptance and promote consumption of safe drinking water; and • Working with departmental staff to pilot Enterococci testing to assess recreational swimming water quality at popular swimming sites to design new policy to reduce public health risk. Regular research briefs and reports to share findings, dissemination and advocacy through peer reviewed journal articles and presentations at professional conferences were used to share the research evidence to stakeholders, policy-makers and peer environmental health practitioners. Results and outcomes Public drinking water sampling adequacy significantly improved (p = 0.002) during the study period. Sampling adequacy was significantly lower in smaller populations (p = 0.013). E. coli detections significantly improved (p < 0.0001) but were significantly higher in smaller communities (p< 0.001). There was a strong inverse correlation between sampling compliance and E. coli detection (p<0.001; R² Linear = 0.72). NSW Health has assisted utilities to develop and implement Drinking Water Management Systems throughout the State. All recreational parks developed and implemented drinking water quality assurance programs. All recreational parks that provided water but do not treat or regularly monitor the quality of the water supplies have installed appropriate warning signs by the NSW Private Water Supply Guidelines, to warn visitors. Private drinking water supplies have now been included in the NSW Public Health Act, and Private Drinking Water Supply Guidelines were amended to include the development and implementation of drinking water quality assurance plans. Aesthetic factors such as water hardness, taste, colour, odours and societal values influence perceptions of risk and quality. Plans are underway to soften town water supply, as requested by the participating Aboriginal community, as this was a major barrier to consumption. All swimming sites exceeded the threshold NHMRC Enterococci illness transmission recreational level of 40 CFU/100 ml. There is a need for risk-based water quality management at informal recreational swimming sites. Conclusion The research demonstrated that improving drinking water sampling frequency was associated with enhanced microbiological water safety. However, there is room for improvement in sampling adequacy and water quality (E. coli detections) in smaller communities. Further dialogue, research, and policy focus is needed that includes partnerships with discrete NSW Aboriginal communities, in order to develop a deeper understanding of their perceptions of drinking water and to encourage consumption of safe water. This research promoted interaction between practitioners, managers and academics in environmental health program development to promote public health. The research clearly demonstrated how using routinely collected data coupled with primary data collection results in strong environmental health practitioner-led research with important policy outcomes. Future research should build on these key strengths, linking environmental health practitioners' fieldwork with productive collaborative networks between academics and policy makers, to promote the development of knowledge that provides evidence-based policy changes for public health benefit