Use and perceptions of worked example videos for first-year students studying mathematics in a primary education degree

Worked example videos have great potential to be useful for students when learning mathematics as they can work through the questions at their own pace, pausing as needed, but still learn from the way the demonstrator thinks and solves problems. We created worked example videos each week for a mathematics subject taught in the first year of a primary education degree and investigated student perceptions and their usage patterns. An additional aspect of this undertaking was the inclusion of subtitles to make the videos accessible to hearing impaired and ESL students. This report will reflect on the process of creating these videos, as well as some initial findings on their success.

Learning feature trajectories using Gabor Filter Bank for human activity segmentation and recognition

We describe a novel method for human activity segmentation and interpretation in surveillance applications based on Gabor filter-bank features. A complex human activity is modeled as a sequence of elementary human actions like walking, running, jogging, boxing, hand-waving etc. Since human silhouette can be modeled by a set of rectangles, the elementary human actions can be modeled as a sequence of a set of rectangles with different orientations and scales. The activity segmentation is based on Gabor filter-bank features and normalized spectral clustering. The feature trajectories of an action category are learnt from training example videos using Dynamic Time Warping. The combined segmentation and the recognition processes are very efficient as both the algorithms share the same framework and Gabor features computed for the former can be used for the later. We have also proposed a simple shadow detection technique to extract good silhouette which is necessary for good accuracy of an action recognition technique. © 2008 IEEE.

Quenched and annealed microstructures of hot worked magnesium AZ31

The microstructures of magnesium AZ31 are examined following hot compression testing and annealing. The grain size, fraction dynamically recrystallized and, in a couple of cases, the crystallographic texture are reported. The progress of dynamic recrystallization and the recrystallized grain size were sensitive to processing conditions, as expected. This effect was more marked in the former than in the latter, compared to other metals. It was also found that, for structures containing between 80 and 95% dynamic recrystallization, abnormal grain growth occurred during annealing. Irrespective of the whether or not abnormal grain growth occurred, the annealing step weakened the crystallographic texture.

Control of the Australian life insurance industry: an example of regulatory externalities within the Australian financial sector 1870-1945

The regulatory environment in which the Australian life insurance industry operates has its antecedents in two major periods of legislative intervention. The first established the principle of ‘freedom with disclosure’ in the 1870s, which has since formed the basis of the regulatory approach. In the 1940s, the second refined the concept in the context of a general recognition of an interventionist approach to financial markets. It is suggested that regulation of the life insurance market in Australia came about not in response to problems associated with market failure but in reaction to external influences not directly related to conditions in the Australian life insurance industry. This was impacted not only on the timing of intervention but on the approach taken as well.

Why invest in a national public health program for stroke? An example using Australian data to estimate the potential benefits and cost implications

Objectives: Stroke is the world’s second leading cause of death in people aged over 60 years. Approximately 50,000 strokes occur annually in Australia with numbers predicted to increase by about one third over 10-years. Our objectives were to assess the economic implications of a public health program for stroke by: (1) predicting what potential health-gains and cost-offsets could be achieved; and (2) determining the net level of annual investment that would offer value-for-money.

Methods: Lifetime costs and outcomes were calculated for additional cases that would benefit if ‘current practice’ was feasibly improved, estimated for one indicative year using: (i) local epidemiological data, coverage rates and costs; and (ii) pooled effect sizes from systematic reviews.

Interventions: blood pressure lowering; warfarin for atrial fibrillation; increased access to stroke units; intravenous thrombolysis and aspirin for ischemic events; and carotid endarterectomy. Value-for-money threshold: AUD$30,000/DALY recovered.

Results: Improved, prevention and management could prevent about 27,000 (38%) strokes in 2015. In present terms (2004), about 85,000 DALYs and AUD$1.06 billion in lifetime cost-offsets could be recovered. The net level of annual warranted investment was AUD$3.63 billion.

Conclusions: Primary prevention, in particular blood pressure lowering, was most effective. A public health program for stroke
is warranted

'Research as dialogue' and cross-cultural consultations : confronting relations of power

ln this paper, we discuss methodological issues that emerged as we worked through a small empirical research project, 'Engaging Aboriginal students in education through community empowerment'. Recent national policy statements (see, for example, MCEETYA 2000,. NBEET 1995) argue the importance of education/research that keeps the locus of control within the Aboriginal community as a means to further the goal of self-determination and improve educational outcomes. In keeping with these recommendations, our project aimed to challenge assimilationist frameworks and sought to 'empower' members of the local Aboriginal community through participation in the project. 'Research as dialogue' was a guiding principal and a primary aim was to listen actively to all key stakeholders in the remote community setting, particularly to lndigenous parents, students and teachers, in order to identify current strengths and concerns regarding the provision of culturally inclusive schooling. A proposed second stage of the project is to develop, on the basis of these consultations and in collaboration, community-based education projects that engage non-attending Aboriginal students. Here we discuss the consultative processes undertaken in stage one of the project, and critically analyse the difficulties as well as potential strengths of trying to form collaborative partnerships as researchers across cultural differences and with diverse community groups.

Data quality issues in practice and theory : a cross-cultural example

Practical considerations and traditions play a substantial role in data collection exercises, often limiting the focus of study to either qualitative or quantitative issues. An industry with a particularly strong quantitative emphasis is the insurance and reinsurance industry, where actuarial decisions are based on detailed and exacting numerical analysis of data that are assumed to be reliable and valid. However, the qualitative investigation of the quality of data in one reinsurance setting reported in this paper shows that where the meanings of the questions asked and of the answers provided are subject to interpretation, the quality of data collected for entry to databases can be poor. While this can be exacerbated in cross-cultural contexts, it is also generally true. Due to the constrained nature of insurance practice, the existence of a range of techniques combining qualitative and quantitative methods is somewhat academic. Therefore, because researchers have the latitude to investigate both qualitative and quantitative factors in the industrial context, a call is made for researchers and industry to work more closely together.

Louise Hanson-Dyer : leading by example

The article provides an example of music patronage, which can be sustained and realized in challenging conditions and focuses on the contribution of music publisher Louise Hanson-Dyer (1884-1962) . Her example demonstrates how patronage inspires confidence in music, elevates standards, and generates more creativity.

Microstructure evolution in hot worked and Annealed Magnesium Alloy AZ31

The present work examines the microstructure that evolves during the annealing of hot worked magnesium alloy AZ31. First, the influences of deformation and annealing conditions on the microstructures are assessed. It is found that the annealing behaviour is consistent with what one would expect for a recrystallization type reaction. Whilst both the deformation and annealing conditions influence the time required to reach a stable annealed microstructure, the grain size attained is governed solely by the prior deformation conditions employed. At the highest temperature and strain rate examined, the rate of recrystallization is quite high and the grain size was found to be approximately double when annealed for only 1 s prior to quenching. Finally, semi-empirical equations are developed to predict the kinetics of recrystallization, as well as the evolution of grain size, during annealing.