A low-cost 3-D laser imaging system

This paper presents the design and development of a low cost three-dimensional laser imaging system for scanning suitable surfaces. A generic, low cost, off-the-shelf laser range finder is used to obtain the primary one dimensional distance measurement. The range finder’s laser beam is reflected by a twin-axis mirror assembly driven by stepper motors providing the system with two angular degrees of freedom, allowing 3-D measurements to be determined. A camera and image processing techniques are used to determine the measured 1-D range value from the generic range-finding device. A computer program then uses the obtained data to create a 3-D point cloud. An algorithm is then used to construct a 3-D wire frame mesh representing the scanned surface. The system has an angular resolution of 1.8° and the results obtained demonstrate the system to have an accuracy of approximately ± 2cm at a scanning distance of 1.0m.

What are grade 5 and 6 children buying from school canteens and what do parents and teachers think about it?

Objective: The foods sold in school canteens have a significant role to play in ensuring children consume a healthy balance of nutritious foods. However, no research to date has described the foods that Australian children are purchasing at school canteens, or the perceptions held about school canteens by students, teachers and parents.
Design: An exploratory cross-sectional survey was used to obtain information from students, parents and teachers through self completion questionnaires.
Subjects: There were 384 children aged nine to 12 years, 404 parents and 41 teachers involved.
Settings: The study was conducted in 12 primary schools in Victoria, Australia.
Main outcome measures: Types of foods purchased at school canteens, school canteen usage, parents' and teachers' perceptions of the role of the school and canteen in influencing children's eating habits.
Results: More than 50% of the children surveyed used the school canteen at least once per week. Children identified preference for unhealthy alternatives and availability as key barriers to choosing healthy foods at the canteen and suggested increased availability, advertisements and cost reductions as aids to purchasing healthy foods. Teachers placed more importance on the role of the canteen than parents did.
Statistical analyses: Frequencies, cross-tabulation analyses and chi square tests were undertaken using the SPSS 11 computer program.
Conclusions: These Victorian primary school children and their teachers, and to a lesser extent parents, had a clear understanding of healthy foods. Children and teachers identified barriers that prevent school canteens
from providing healthy foods. There is likely to be strong support from these stakeholders for novel health promoting policies.

'Marvin the Mouse'; can he assist police to elicit evidence from young children?

This study investigated the usefulness of a computer program designed to assess young children's understanding of words that may be relevant to an investigative interview about assault. Forty-one police officers conducted two interviews with five- to six-year-old children (one was conducted with the program and one without). The program's effectiveness was based on the interviewers' ratings of the usefulness of the program as well as three independent indices of interviewer-child rapport. Overall, the police officers perceived the program to be an extremely useful pre-interview assessment. However, the program had little impact on the officers' style of questioning and the nature of the children's responses. The implications of these findings are discussed.

Utilising solar energy within conventional coal fired power stations

Although the thermodynamic advantages of using solar energy to replace the bled off steam in the regeneration system of Rankine cycle coal fired power stations has been proven theoretically, the practical techno/economic feasibility of the concept has yet to be confirmed relative to real power station applications. To investigate this concept further, computer modelling software “THERMSOLV” was specifically developed for this project at Deakin University, together with the support of the Victorian power industry and Australian Research Council (ARC). This newly developed software simulates the steam cycle to assess the techno/economic merit of the solar aided concept for various power station structures, locations and local electricity market conditions. Two case studies, one in Victoria Australia and one in Yunnan Province, China, have been carried out with the software. Chapter one of this thesis defines the aims and scope of this study. Chapter two details the literature search in the related areas for this study. The thermodynamic concept of solar aid power generation technology has been described in chapter three. In addition, thermodynamic analysis i.e. exergy/availability has been described in this chapter. The “Thermosolv” software developed in this study is detailed in chapter four with its structure, functions and operation manual included. In chapter five the outcomes of two case studies using the “Thermosolv” software are presented, with discussions and conclusions about the study in chapters 6 and 7 respectfully. The relevant recommendations are then made in chapter eight.

Evaluation of heat stress indices using physiological comparisons in an alumina refinery in a sub-tropical climate

The production of alumina involves the use of a process known as the Bayer process. This method involves the digestion of raw bauxite in sodium hydroxide at temperatures around 250°C. The resultant pregnant liquor then goes through a number of filtering and precipitation processes to obtain the aluminium oxide crystals which are then calcined to obtain the final product. The plant is situated in a sub tropical climate in Northern Australia and this combined with the hot nature of the process results in a potential for heat related illnesses to develop. When assessing a work environment for heat stress a heat stress index is often employed as a guideline and to date the Wet Bulb Globe Temperature (WBGT) has been the recommended index. There have been concerns over the past that the WBGT is not suited to the Northern Australian climate and in fact studies in other countries have suggested this is the case. This study was undertaken in the alumina plant situated in Gladstone Queensland to assess if WBGT was in fact the most suitable index for use or if another was more applicable. To this end three indices, Wet Bulb Globe Temperature (WBGT), Heat Stress Index (HSI) and Required Sweat Rate (SWreq) were compared and assessed using physiological monitoring of heart rate and surrogate core temperature. A number of different jobs and locations around the plant were investigated utilising personal and environmental monitoring equipment. These results were then collated and analysed using a computer program written as part of the study for the manipulation of the environmental data . Physiological assessment was carried out using methods approved by international bodies such as National Institute for Occupational Safety & Health (NIOSH) and International Standards Organisation (ISO) and incorporated the use of a ‘Physiological Factor’ developed to enable the comparison of predicted allowable exposure times and strain on the individual. Results indicated that of the three indices tested, Required Sweat Rate was found to be the most suitable for the climate and in the environment of interest. The WBGT system was suitable in areas in the moderate temperature range (ie 28 to 32°C) but had some deficiencies above this temperature or where the relative humidity exceeded approximately 80%. It was however suitable as a first estimate or first line indicator. HSI over-estimated the physiological strain in situations of high temperatures, low air flows and exaggerated the benefit of artificial air flows on the worker in certain environments ie. fans.

Casting yield improvement in graphite iron castings

A well designed runner and feeding system should produce castings with minimal defects and low pour weight. This thesis investigates how the filling regime and solidification of the mould influences defects in the castings produced from that mould. Design guidelines to reduce such defects are proposed and tested. An existing shrinkage fault in a Grey Iron disc brake casting is simulated using a commercial finite-difference computer program. Three criteria are used to predict the defect and the effect of changes to the feeder geometry. Critical Fraction Solidification analysis is used to determine whether the feeder remains in liquid contact with the casting during solidification and this approach is shown to correctly predict the presence or absence of porosity* The feeder block is extended below the ingate of the casting to improve liquid contact between the casting and feeder without significantly increasing the feeder mass. Plant trials confirm the change to the feeder eliminates the porosity defect. The runner system and mould venting for a thin walled Ductile Iron casting are investigated. Trials show that by setting the total mould vent area to be greater than the net ingate area of the castings, the cold-shut frequency is halved. A method for runner system design based on peak linear flow velocity in the runner during mould filling is proposed. A new pressurised runner system produces castings with significantly fewer defects and reduced pour weight when runner areas are designed to maintain peak velocity below 1 m/s. Peak velocity and magnesium levels are demonstrated to be critical factors in the elimination of cold-shut defects. A pressurised runner system is also shown to isolate inclusion defects from castings more effectively than an unpressurised system. From this work, a technique is proposed which allows the yield of an existing runner and feeder system for iron castings to be improved with confidence in the results.

Identifying a taxonomy for the emergence of metacognition in young learners

This paper details a study of upper primary (elementary) students’ thinking as they go about solving a problem, presented in an innovative computer program. Student responses to a metacognitive probe question reveal levels of responses that can be classified because of their shared quality. A thematic analysis was conducted with the initial classifications being based on theoretically derived categories from the metacognitive literature. These classifications were subsequently ordered into a taxonomy of hierarchical progression towards metacognition. Results in this instance indicated that less than 20% of these upper primary students showed they were capable of operating at a metacognitive level.

Population outcomes of three approaches to detection of congenital hearing loss

BACKGROUND: Universal newborn hearing screening was implemented worldwide largely on modeled, not measured, long-term benefits. Comparative quantification of population benefits would justify its high cost.

METHODS: Natural experiment comparing 3 population approaches to detecting bilateral congenital hearing loss (>25 dB, better ear) in Australian states with similar demographics and services: (1) universal newborn hearing screening, New South Wales 2003-2005, n = 69; (2) Risk factor screening (neonatal intensive care screening + universal risk factor referral), Victoria 2003-2005, n = 65; and (3) largely opportunistic detection, Victoria 1991-1993, n = 86. Children in (1) and (2) were followed at age 5 to 6 years and in (3) at 7 to 8 years. Outcomes were compared between states using adjusted linear regression.

RESULTS: Children were diagnosed younger with universal than risk factor screening (adjusted mean difference -8.0 months, 95% confidence interval -12.3 to -3.7). For children without intellectual disability, moving from opportunistic to risk factor to universal screening incrementally improved age of diagnosis (22.5 vs 16.2 vs 8.1 months, P < .001), receptive (81.8 vs 83.0 vs 88.9, P = .05) and expressive (74.9 vs 80.7 vs 89.3, P < .001) language and receptive vocabulary (79.4 vs 83.8 vs 91.5, P < .001); these nonetheless remained well short of cognition (mean 103.4, SD 15.2). Behavior and health-related quality of life were unaffected.

CONCLUSIONS: With new randomized trials unlikely, this may represent the most definitive population-based evidence supporting universal newborn hearing screening. Although outperforming risk factor screening, school entry language still lagged cognitive abilities by nearly a SD. Prompt intervention and efficacy research are needed for children to reach their potential.

Introductory computer programming as a means for extending spatial and temporal understanding

Should computer programming be taught within schools of architecture?

Incorporating even low-level computer programming within architectural education curricula is a matter of debate but we have found it useful to do so for two reasons: as an introduction or at least a consolidation of the realm of descriptive geometry and in providing an environment for experimenting in morphological time-based change.

Mathematics and descriptive geometry formed a significant proportion of architectural education until the end of the 19th century. This proportion has declined in contemporary curricula, possibly at some cost for despite major advances in automated manufacture, Cartesian measurement is still the principal ‘language’ with which to describe building for construction purposes. When computer programming is used as a platform for instruction in logic and spatial representation, the waning interest in mathematics as a basis for spatial description can be readdressed using a left-field approach. Students gain insights into topology, Cartesian space and morphology through programmatic form finding, as opposed to through direct manipulation.

In this context, it matters to the architect-programmer how the program operates more than what it does. This paper describes an assignment where students are given a figurative conceptual space comprising the three Cartesian axes with a cube at its centre. Six Phileban solids mark the Cartesian axial limits to the space. Any point in this space represents a hybrid of one, two or three transformations from the central cube towards the various Phileban solids. Students are asked to predict the topological and morphological outcomes of the operations. Through programming, they become aware of morphogenesis and hybridisation. Here we articulate the hypothesis above and report on the outcome from a student group, whose work reveals wider learning opportunities for architecture students in computer programming than conventionally assumed.

Impact of the Learn to Play program on play, social competence and language for children aged 5 - 8 years who attend a specialist school

Introduction
The aim of this study was to investigate the change in the relationship between play, language and social skills of children aged 5–8 years pre and post participation in the ‘Learn to Play’ program. The Learn to Play program is a child led play based intervention aimed at developing self-initiated pretend play skills in children.

Methods
All 19 participants attended a specialist school, with 10 of the 19 children having a diagnosis of autism. The play, language and social skills of the children were assessed at baseline and at follow up. Children were assessed using the Child-Initiated Pretend Play Assessment, the Preschool Language Scale and the Penn Interactive Peer Play Scale. Follow up data collection occurred after the children had been participating in the Learn to Play program for 1 hour twice a week for 6 months.

Results
After 6 months in the program, typical indicators of play accounted for an increase of 47.3% in shared variance with social interaction and an increase of 36% in shared variance for social connection. For language, object substitution ability accounted for 50% of the shared variance, which was an increase of 27% from baseline.

Conclusion
The ‘Learn to Play’ program was associated with increases in children's language and social skills over a 6-month period within a special school setting, indicating the Learn to Play program is an effective intervention for children with developmental disabilities. This paper presents an example of how the Learn to Play program can be adapted into a classroom setting.

A data quality control program for computer-assisted personal interviews

Researchers strive to optimize data quality in order to ensure that study findings are valid and reliable. In this paper, we describe a data quality control program designed to maximize quality of survey data collected using computer-assisted personal interviews. The quality control program comprised three phases: (1) software development, (2) an interviewer quality control protocol, and (3) a data cleaning and processing protocol. To illustrate the value of the program, we assess its use in the Translating Research in Elder Care Study. We utilize data collected annually for two years from computer-assisted personal interviews with 3004 healthcare aides. Data quality was assessed using both survey and process data. Missing data and data errors were minimal. Mean and median values and standard deviations were within acceptable limits. Process data indicated that in only 3.4% and 4.0% of cases was the interviewer unable to conduct interviews in accordance with the details of the program. Interviewers’ perceptions of interview quality also significantly improved between Years 1 and 2. While this data quality control program was demanding in terms of time and resources, we found that the benefits clearly outweighed the effort required to achieve high-quality data.

Assessment of a six-week computer-based remediation program for social cognition in chronic schizophrenia

Background: Programs to remediate cognitive deficits have shown promising results in schizophrenia, but remediation of social cognition deficits is less well understood. Social cognitive deficits may cause more disability than the widely recognized neurocognitive deficits, suggesting that this is an area worthy of further investigation. Aim: Implement and evaluate a brief computerized cognitive remediation program designed to improve memory, attention, and facial affect recognition (FAR) in outpatients with chronic schizophrenia.

Methods: Baseline assessments of FAR and of clinical, cognitive, and psychosocial functioning were completed on 20 males with schizophrenia enrolled in an outpatient rehabilitation program at the Shanghai Mental Health Center (the intervention group) and on 20 males with schizophrenia recruited from among regular outpatients at the Center (the control group). Both groups received treatment as usual, but the intervention group also completed an average of 12.7 sessions of a computer-based remediation program for neurocognitive, social, and FAR functioning over a 6-week period. The baseline measures were repeated in both groups at the end of the 6-week trial.

Results: There were no statistically significant differences in the changes in clinical symptoms (assessed by the Positive and Negative Syndrome Scale, PANSS) or cognitive measures (assessed using the Hong Kong List Learning Test and the Letter-Number Sequencing Task) between the intervention and control groups over the 6-week trial, but there were modest improvements on the PANSS for the intervention group between baseline and after the intervention. There was a significantly greater improvement in the social functioning measure (the Personal and Social Performance scale, PSP) in the intervention group than in the control group. The pre-post change in the total facial recognition score in the intervention group was statistically significant (paired t-test=-2.60, p=0.018), and there was a statistical trend of a greater improvement in facial recognition in the intervention group than in the control group (F(1,37)=2.93; p=0.092).

Conclusions: Integration of FAR training with a short, computer-administrated cognitive remediation program may improve recognition of facial emotions by individuals with schizophrenia, and, thus, improve their social functioning. But more work on developing the FAR training modules and on testing them in larger, more diverse samples will be needed before this can be recommended as a standard part of cognitive remediation programs.