Spatial reasoning by active observation

The problem of deriving spatial relationships between objects in general requires high lever' abstract representation, and it would pose difficulties even for human observer. Based on a formalism for spatial layouts proposed earlier, we present methods for deducing spatial relations between objects by an active, sighted agent in a large-scale environment. The deduction of spatial relations is based on simple visual clues, and thus this technique is more feasible than schemes that rely on complex object recognition.

Video indexing by spatial representation

Recent approaches to video indexing and retrieval are either pixel-oriented or object-oriented. While the former approaches focus on motion and changes thereto, the latter focus on spatial relations among objects in the scene. In this paper, a spatial knowledge representation technique combining both approaches is proposed. This representation supplements the spatial knowledge of visual objects with information about their pixel positions in the video frame. It provides a practical way to construct video indices, enabling searching for and retrieval of video sequences that contain motion as well as sparsely disjoint objects

Automated film rhythm extraction for scene analysis

This paper examines film rhythm, an important expressive element in motion pictures, based on our ongoing study to exploit film grammar as a broad computational framework for the task of automated film and video understanding. Of the many, more or less elusive, narrative devices contributing to film rhythm, this paper discusses motion characteristics that form the basis of our analysis, and presents novel computational models for extracting rhythmic patterns induced through a perception of motion. In our rhythm model, motion behaviour is classified as being either nonexistent, fluid or staccato for a given shot. Shot neighbourhoods in movies are then grouped by proportional makeup of these motion behavioural classes to yield seven high-level rhythmic arrangements that prove to be adept at indicating likely scene content (e.g. dialogue or chase sequence) in our experiments. Underlying causes for this level of codification in our approach are postulated from film grammar, and are accompanied by detailed demonstration from real movies for the purposes of clarification.

Deduction of high level spatial relations

The problem of deriving spatial relationships between objects in general requires high level abstract representation, and it would pose difficulties even for human observer. Based on a formalism for spatial layouts proposed earlier [KiV92, VeK921, we present methods for deducing high level spatial relations between objects by an active, sighted agent in a large-scale environment. The deduction of spatial relations is based on simple visual clues, and thus this technique is more feasible than schemes that rely on complex object recognition.

Detecting indexical signs in film audio for scene interpretation

In this paper, we study the sound tracks in films and their indexical semiotic usage by developing a classification system that detects complex sound scenes and their constituent sound events in cinema. We investigate two main issues in this paper: Determination of what constitutes the presence of a high level sound scene and inferences about the thematic content of the scene that can be drawn from this presence, and classification of environmental sounds in the audio track of the scene, to assist in the automatic detection of the high level scene. Experiments with our classification system on pure sounds resulted in a correct event classification rate of 88.9%. When the audio content of a number of film scenes was examined, though a lower accuracy resulted with sound event detection due to the presence of mixed sounds, the film audio samples were generally classified with the correct high-level sound scene label, enabling correct inferences about the story content of the scenes.

Determining dramatic intensification via flashing lights in movies

Movie directors and producers worldwide, in their quest to narrate a good story that warrants repeated audience viewing, use many cinematic elements to intensify and clarify the viewing experience. One such element that directors manipulate is lighting. In this paper we examine one aspect of lighting, namely flashing lights, and its role as an intensifier of dramatic effects in film. We present an algorithm for robust extraction of flashing lights and a simple mechanism to group detected flashing lights into flashing light scenes and analyze the role of these segments in story narration. In addition, we demonstrate how flashing lights detection can improve the performance of shot-based video segmentation. Experiments on a number of video sequences extracted from real movies yields good results. Our technique detects 90.4% of flashing lights. The detected flashing lights correctly eliminates 92.7% of false cuts in these sequences. In addition, data support is compiled to demonstrate the association between flashing light scenes and certain dramatic intensification events such as supernatural power, crisis or excitement.

Analysis of the current distribution in an aluminum electrolysis cell with copper collector-bar cathode assembly

Understanding the magneto-hydrodynamic forces generated due to the external magnetic field and current density distribution within the cell (current in cell linings) is important in the optimization of cell dynamics. It is well documented that these factors play a crucial role in establishing the metal-pad stability of the cell. Conventional cells use the cathode-collector-bar assembly to carry the current through molten aluminium, the cathode and the steel collector-bar to nearest external bus. The electrical conductivity of the steel is so poor relative to the molten aluminium that the outer third of the collector bar carries the maximum load, which in turn increases the horizontal components of the current within the cell. Previous studies have modelled improvement in the cell instability through external magnetic compensation by redistributing current in the cathode busbar. Very little to date has been published on work to improve the current distribution within the cell. In this work, the current distribution in an aluminium electrolysis cell with copper collector-bar was predicted using finite element modelling. A 2D cross-section of a commercial cell was used under steady conditions of electrical fields in anode, electrolyte, molten aluminium and copper cathode-assembly. Different shapes and sizes of the cathode assembly are also considered to optimise the distribution of current throughout the cathode lining. The findings indicated that the copper-bar of similar size to steel could save voltage up to 150 mV. There is a reduction of more than 70% in peak current density value due to the copper inserts. The predicted trends of current distribution show a good agreement with previously published data.

Effects of ultrasonic treatment on wool fibre and fabric properties

The protein structures of wool, treated in fabric form with ultrasonics for different time durations, were analysed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR), in comparison with the wool without ultrasonic treatment. Fabric water absorption and tensile properties were measured in addition to the fibre micro-structure analysis. It is shown that while the ultrasonic treatment had little effect on the fibre crystallinity, some chemical structures in the protein were altered to some extent during the process. Disruption of fibre internal waxy lipids upon ultrasonic treatment provided the fibres with increased water absorption. Protein chains in the macro fibrils were shown to be rearranged to a more regular and less flexible structure, as a result of the ultrasonic treatment. Fabric tensile tests showed an increased tenacity and a reduced extensibility to the ultrasonically treated fabric. Prolonged ultrasonic treatment, however, significantly reduced both fabric tenacity and extensibility.

Changes in wool protein structure and fabric properties with ultrasonic treatment

Wool fabrics, ultrasonically treated for different time durations, were analysed by Fourier transform infrared (FTIR), differential scanning calorimeter (DSC), and thermo-gravimetric analysis (TGA), in comparison with the wool without ultrasonic treatment. Fabric tensile and thermal properties were measured in addition to the fibre micro structure analysis. Wool protein chains in the macro fibrils were shown to be rearranged to a more regular and less flexible structure, as a result of the ultrasonically treated fabric. Prolonged ultrasonic treatment, however, significantly reduced both fabric tenacity and extensibility. Wool treated with ultrasonics was found to have less mass loss and a higher thermal degradation temperature than that of without ultrasonic treatment and prolonged treated. DSC analysis showed that while ultrasonic treatment has little effect on the fibre crystallinity, an appropriate treatment can provide wool with increased water absorption.

A systems approach to shape and topology optimisation of mechanical structures

Optimisation techniques have become more and more important as the possibility of simulating complex mechanical structures has become a reality. A common tool in the layout design of structural parts is the topology optimisation method, which finds an optimum material distribution within a given geometrical design space to best meet loading conditions and constraints. Another important method is shape optimisation, which optimises weight given parametric geometric constraints. In the case of complex shaped parts or elaborate assemblies, for example automobile body structures, shape optimisation is still hard to do; mainly due to the difficulty in translating shape design parameters into meaningful analysis models. Tools like the parametric geometry package SFE CONCEPT are designed to mitigate these issues. Nevertheless, shape methods usually cannot suggest new load path configurations, while topology methods are often confined to single parts. To overcome these limitations the authors have developed a method that combines both approaches into an Integral Shape/Topology Method (IST) that is capable of finding new optimal solutions. This is achieved by an automated optimisation loop and can be applied for both thin walled structures as well as solid 3D geometries. When optimising structures by applying IST, global optimum solutions can be determined that may not be obtained with isolated shape- or topology-optimisation methods.

Exploiting side information in distance dependent Chinese restaurant processes for data clustering

Multimedia contents often possess weakly annotated data such as tags, links and interactions. The weakly annotated data is called side information. It is the auxiliary information of data and provides hints for exploring the link structure of data. Most clustering algorithms utilize pure data for clustering. A model that combines pure data and side information, such as images and tags, documents and keywords, can perform better at understanding the underlying structure of data. We demonstrate how to incorporate different types of side information into a recently proposed Bayesian nonparametric model, the distance dependent Chinese restaurant process (DD-CRP). Our algorithm embeds the affinity of this information into the decay function of the DD-CRP when side information is in the form of subsets of discrete labels. It is flexible to measure distance based on arbitrary side information instead of only the spatial layout or time stamp of observations. At the same time, for noisy and incomplete side information, we set the decay function so that the DD-CRP reduces to the traditional Chinese restaurant process, thus not inducing side effects of noisy and incomplete side information. Experimental evaluations on two real-world datasets NUS WIDE and 20 Newsgroups show exploiting side information in DD-CRP significantly improves the clustering performance.

Assessing students’ attitudes toward forensic science: collecting an expert consensus

We report the development of an affective domain instrument for the assessment of undergraduate students’ attitudes toward forensic science. Assessment of attitudes of the respondents is important to understand mediating factors in student motivation and ultimately success in the discipline. The instrument was developed using an iterative process based on responses from an expert panel of Australian forensic science educators to an array of forensic science and teaching related topics, and refined using further feedback from the panel on more specific items. The layout of the instrument, with regard to both the wording and placement of items, was developed with regular test takers (i.e., students) in mind and through the application of basic psychometric principles. The engagement of forensic science colleagues across Australia has resulted in an outcome that could provide a source of credible and relevant evidence of student attitudes toward forensic science.

Bioinspired strategy to reinforce PVA with improved toughness and thermal properties via hydrogen-bond self-assembly

Despite the high strength and stiffness of polymer nanocomposites, they usually display lower deformability and toughness relative to their matrices. Spider silk features exceptionally high stiffness and toughness via the hierarchical architecture based on hydrogen-bond (H-bond) assembly. Inspired by this intriguing phenomenon, we here exploit melamine (MA) to reinforce poly(vinyl alcohol) (PVA) via H-bond self-assembly at a molecular level. Our results have shown that due to the formation of physical cross-link network based on H-bond assembly between MA and PVA, yield strength, Young’s modulus, extensibility, and toughness of PVA are improved by 22, 25, 144, and 200% with 1.0 wt % MA, respectively. Moreover, presence of MA can enhance the thermal stability of PVA to a great extent, even exceeding some nanofillers (e.g., graphene). This work provides a facile method to improve the mechanical properties of polymers via H-bond self-assembly.

Regulation of scleral cell contraction by transforming growth factor-β and stress competing roles in myopic growth

Reduced extracellular matrix accumulation in the sclera of myopic eyes leads to increased ocular extensibility and is related to reduced levels of scleral transforming growth factor-β (TGF-β). The current study investigated the impact of this extracellular environment on scleral cell phenotype and cellular biomechanical characteristics. Scleral cell phenotype was investigated in vivo in a mammalian model of myopia using the myofibroblast marker, α-smooth muscle actin (α-SMA). In eyes developing myopia α-SMA levels were increased, suggesting increased numbers of contractile myofibroblasts, and decreased in eyes recovering from myopia. To understand the factors regulating this change in scleral phenotype, the competing roles of TGF-β and mechanical stress were investigated in scleral cells cultured in three-dimensional collagen gels. All three mammalian isoforms of TGF-β altered scleral cell phenotype to produce highly contractile, α-SMA-expressing myofibroblasts (TGF-β3 > TGF-β2 > TGF-β1). Exposure of cells to the reduced levels of TGF-β found in the sclera in myopia produced decreased cell-mediated contraction and reduced α-SMA expression. These findings are contrary to the in vivo gene expression data. However, when cells were exposed to both the increased stress and the reduced levels of TGF-β found in myopia, increased α-SMA expression was observed, replicating in vivo findings. These results show that although reduced scleral TGF-β is a major contributor to the extracellular matrix remodeling in the myopic eye, it is the resulting increase in scleral stress that dominates the competing TGF-β effect, inducing increased α-SMA expression and, hence, producing a larger population of contractile cells in the myopic eye.

The effects of physical environments in medical wards on medication communication processes affecting patient safety

Physical environments of clinical settings play an important role in health communication processes. Effective medication management requires seamless communication among health professionals of different disciplines. This paper explores how physical environments affect communication processes for managing medications and patient safety in acute care hospital settings. Findings highlighted the impact of environmental interruptions on communication processes about medications. In response to frequent interruptions and limited space within working environments, nurses, doctors and pharmacists developed adaptive practices in the local clinical context. Communication difficulties were associated with the ward physical layout, the controlled drug key and the medication retrieving device. Health professionals should be provided with opportunities to discuss the effects of ward environments on medication communication processes and how this impacts medication safety. Hospital administrators and architects need to consider health professionals' views and experiences when designing hospital spaces.