Reduction of Machine Tool Times Through a Software/Hardware Integrated Solution

Toolmaking is an industry that creates metal moulds, generally of durable tool steels, for producing vacuum-formed and injection moulded plastic parts, which are used in thousands of everyday items such as mobile phones. At present toolmaking is labour intensive with each machining operation requiring manual supervision. The FASTOOL project was a European Union funded collaboration that was aimed at reducing the manpower content of mould toolmaking, and extending the working day. This paper focuses on one element which utilised specially created scheduling and control software that operated an automated overhead gantry system and could remotely start the workshop machines. The software was completely object oriented which allows future proofing by creating new objects for new machines. The results demonstrate that this manufacturing process can be automated, leading to better working conditions for employees and an increase in efficiency and profitability.Mechanical Engineerin

Community structure and intertidal zonation of the macrobenthos on a macrotidal, ultra-dissipative sandy beach: summer-winter comparison

Community structure and intertidal zonation of the macrobenthos on a macrotidal, ultra-dissipative beach were studied. On the beach of De Panne, Belgium, six transects perpendicular to the waterline (each with five stations) were sampled in September 1995 (summer) and March 1996 (winter). The 30 stations were distributed across the continuum from mean high water spring to mean low water spring in order to sample the macrobenthos at different levels of elevation. The 39 species found had total densities up to 5,500 ind m-2 in summer and 1,400 ind m-2 in winter. The highest densities were found in the spionid polychaetes Scolelepis squamata and Spio filicornis, the nephtyid polychaete Nephtys cirrosa, the cirolanid isopod Eurydice pulchra, and the haustorid amphipods Bathyporeia spp. Based on species composition, specific densities, and biomass, two species associations were defined: a relatively species-poor, high intertidal species association, dominated by S. squamata and with an average density of 1,413 ind m-2 and biomass of 808 mg AFDW m-2 (summer); and a relatively species-rich, low intertidal species association, dominated by N. cirrosa, and with an average density of 104 ind m-2 and biomass of 162 mg AFDW m-2 in summer. For both seasons, the high intertidal species association was restricted in its intertidal distribution between the mean tidal and the mean high-water spring level, whereas the low intertidal species association was found from the mean tidal level to the subtidal. The latter showed good affinities with the subtidal N. cirrosa species association, occurring just offshore of De Panne beach, confirming the existence of a relationship between the low intertidal and subtidal macrobenthic species associations. Summer-winter comparison revealed a strong decrease in densities and biomass in the high intertidal zone during winter. Habitat continuity of the low intertidal zone with the subtidal allows subtidal organisms to repopulate the low intertidal zone

On using Feature Descriptors as Visual Words for Object Detection within X-ray Baggage Security Screening

Here we explore the use of various feature point descriptors as visual word variants within a Bag-of-Visual-Words (BoVW) representation scheme for image classification based threat detection within baggage security X-ray imagery. Using a classical BoVW model with a range of feature point detectors and descriptors, supported by both Support Vector Machine (SVM) and Random Forest classification, we illustrate the current performance capability of approaches following this image classification paradigm over a large X-ray baggage imagery data set. An optimal statistical accuracy of 0.94 (true positive: 83%; false positive: 3.3%) is achieved using a FAST-SURF feature detector and descriptor combination for a firearms detection task. Our results indicate comparative levels of performance for BoVW based approaches for this task over extensive variations in feature detector, feature descriptor, vocabulary size and final classification approach. We further demonstrate a by-product of such approaches in using feature point density as a simple measure of image complexity available as an integral part of the overall classification pipeline. The performance achieved characterises the potential for BoVW based approaches for threat object detection within the future automation of X-ray security screening against other contemporary approaches in the field

Evaluation of a Community-wide Diabetes Prevention Program

This thesis is an evaluation of the effectiveness of a community-wide diabetes prevention program conducted in three Divisions of General Practice in Sydney, Australia. The aims were to assess whether translation of diabetes prevention programs was feasible in real-life settings and whether results achieved were comparable with those of randomised trials on which this intervention was based. Its primary goals were to assess whether the lifestyle intervention could increase participation in moderate-to-vigorous physical activity to 210 minutes per week, reduce total fat and saturated fat consumption to 30% and 10% of total daily energy intake, increase fibre consumption to 15 g/1,000 kcal/day, and lead to 5% weight loss over one year. The background section covers the physiopathology of type 2 diabetes, its risk factors, and the available population screening tools to identify people at risk. The growing morbidity and mortality burden, the economic implications of this public health problem, and the importance and feasibility of preventing or delaying the onset by intervening in the precursor stages are then summarised. Evidence for preventability is examined through a literature review of lifestyle interventions in research settings comprising highly structured and closely monitored physical activity and dietary programs under controlled conditions. Examples of the effectiveness of translation of randomised controlled trials (RCTs) into less stringent programs in community settings such as workplaces, churches, indigenous communities and whole-of-country initiatives are presented. A systematic review and meta-analysis of effectiveness of the lifestyle approaches in routine clinical practice supplements the evidence for application of prevention principles in real-life settings. The main chapters of the thesis centre on process and impact evaluation of the semi-structured Sydney-based intervention, which recruited 1,250 participants from the mainstream Australian 29 public using general practitioner services in the study area, who were followed for 12 months. The intervention’s goals aligned with those of the Finnish Diabetes Prevention Program but with less stringent entry criteria and less intensive intervention components delivered by purpose-trained lifestyle officers. The Program included an initial individual assessment and coaching session, three subsequent group sessions in the following three months, then three follow-up coaching calls at three, six and nine months. A final assessment at one year, using the same objective and self-reported measures as in the initial assessment, captured changes in body weight, physical activity and dietary habits. The process evaluation showed that it is feasible and effective to use targeted screening to identify and recruit high-risk individuals into a free-of-charge program in the general practice setting, however a quarter of participants were lost to follow-up by one year. While minor variations in aspects of the Program were required to meet local need, Program fidelity in delivering components, and self-reported adherence to diet and physical activity was high. Using a before-after study design, the impact evaluation measured 1-year changes in key Program parameters in relation to baseline. These comprised: measured weight, waist circumference, BMI, and glycaemia measurements; and self-reported dietary intake and structured physical activity, using a 3-day food record and the Physical Activity Scale for the Elderly (PASE) questionnaire, respectively. The main findings at 12 months for the 586 completers as at December 2010 were: a mean weight loss of 2.1 kg; waist circumference reduction of 2.5 cm; no significant change in glycaemia; 3% reduction of fat and saturated fat intake; 16% increase in fibre intake; and mean increase in moderate-to-vigorous physical activity of 13.7 minutes/week. All these changes were smaller than those achieved by the RCTs in research settings, most likely due to the lower intensity and monitoring of the Sydney intervention. Weight loss and waist circumference reductions were similar for participants in 30 group session and those who received telephone-only coaching. Diabetes incidence was 1% at the end of the first year. An economic appraisal of the Program implementation completes the evaluation. A cost of A$400 per kg lost among people achieving the weight goal was estimated on Program completion, but the cost was double for the overall group that included non weight losers. The cost of achieving the physical activity goal and the dietary goals was not feasible or sustainable with resources available in routine clinical settings. The costs per outcome were similar for participants not attending group sessions, who received only telephone coaching. Hence it is worth exploring this less labour-intensive modality if a general practice based Program were to be delivered as routine preventive care. In sum, the evaluation of this community-wide diabetes prevention program showed that translation of diabetes prevention programs into routine practice, while feasible at less intensive levels than in RCTs, has a somewhat lower effect on diabetes risk reduction and it can still be a financial burden in clinical settings. However, given the potential for population-wide benefit, the effectiveness of alternative delivery modes, number and duration of program components and more targeted patient sub-groups should be investigated.The Sydney Diabetes Prevention Program was funded by New South Wales Health as part of the Australian Better Health Initiative. Financial contribution and other in-kind support were provided by the Sydney South West Area Health Service and the Australian Diabetes Council -NSW

Multistep Model Predictive Control for Cascaded H-Bridge Inverters: Formulation and Analysis

© 1986-2012 IEEE. In this paper, a suitable long prediction horizon (multistep) model predictive control (MPC) formulation for cascaded H-bridge inverters is proposed. The MPC is formulated to include the full steady-state system information in terms of output current and output voltage references. Generally, basic single-step predictive controllers only track the current references. As a distinctive feature, the proposed MPC also tracks the control input references, which in this case is designed to minimize the common-mode voltage (CMV). This allows the controller to address both output current and CMV targets in a single optimization. To reduce the computational effort introduced by a long prediction horizon implementation, the proposed MPC formulation is transformed into an equivalent optimization problem that can be solved by a fast sphere decoding algorithm. Moreover, the benefits of including the control input references in the proposed formulation are analyzed based on this equivalent optimization problem. This analysis is key to understand how the proposed MPC formulation can handle both control targets. Experimental results show that the proposal provides an improved steady-state performance in terms of current distortion, inverter voltages symmetry, and CMV

Modelling fish habitat preference with a genetic algorithm-optimized Takagi-Sugeno model based on pairwise comparisons

Species-environment relationships are used for evaluating the current status of target species and the potential impact of natural or anthropogenic changes of their habitat. Recent researches reported that the results are strongly affected by the quality of a data set used. The present study attempted to apply pairwise comparisons to modelling fish habitat preference with Takagi-Sugeno-type fuzzy habitat preference models (FHPMs) optimized by a genetic algorithm (GA). The model was compared with the result obtained from the FHPM optimized based on mean squared error (MSE). Three independent data sets were used for training and testing of these models. The FHPMs based on pairwise comparison produced variable habitat preference curves from 20 different initial conditions in the GA. This could be partially ascribed to the optimization process and the regulations assigned. This case study demonstrates applicability and limitations of pairwise comparison-based optimization in an FHPM. Future research should focus on a more flexible learning process to make a good use of the advantages of pairwise comparisons