134 research outputs found
A Multi-Dataset Characterization of Window-based Hyperparameters for Deep CNN-driven sEMG Pattern Recognition
The control performance of myoelectric prostheses would not only depend on the feature extraction and classification algorithms but also on interactions of dynamic window-based hyper-parameters (WBHP) used to construct input signals. However, the relationship between these hyper-parameters and how they influence the performance of the convolutional neural networks (CNNs) during motor intent decoding has not been studied. Therefore, we investigated the impact of various combinations of WBHP (window length and overlap) employed for the construction of raw 2-dimensional (2D) surface electromyogram signals on the performance of CNNs when used for motion intent decoding. Moreover, we examined the relationship between the window length of the 2D sEMG and three commonly used CNN kernel sizes. To ensure high confidence in the findings, we implemented three CNNs which are variants of the existing models, and a newly proposed CNN model. Experimental analysis was conducted using three distinct benchmark databases, two from upper limb amputees and one from able-bodied subjects. The results demonstrate that the performance of the CNNs improved as the overlap between consecutively generated 2D signals increased, with 75% overlap yielding the optimal improvement by 12.62% accuracy and 39.60% F1-score compared to no overlap. Moreover, the CNNs performance was better for kernel size of seven than three and five across the databases. For the first time, we have established with multiple evidence that WBHP would substantially impact the decoding outcome and computational complexity of deep neural networks, and we anticipate that this may spur positive advancement in myoelectric control and related fields
Listening for policy change: How the voices of disabled people shaped Australia’s National Disability Insurance Scheme
Voice has become an important yet ambivalent tool for the recognition of disability. The transformative potential of voice is dependent on a political commitment to listening to disabled people. To focus on listening redirects accountability for social change from disabled people to the ableist norms, institutions and practices that structure which voices can be heard in policy debates. In this paper, I use disability theory on voice and political theory on listening to examine policy documents for the National Disability Insurance Scheme in light of claims made by the disability movement. Although my study finds some evidence of openness in the policy development stage, the scheme falls short of valuing the diverse voices of disabled people as partners in shared dialogue
Challenge of conducting a placebo-controlled randomized efficacy study for influenza vaccine in a season with low attack rate and a mismatched vaccine B strain: a concrete example
<p>Abstract</p> <p>Background</p> <p>Our aim was to determine the efficacy of a trivalent inactivated split virus influenza vaccine (TIV) against culture-confirmed influenza A and/or B in adults 18 to 64 years of age during the 2005/2006 season in the Czech Republic.</p> <p>Methods</p> <p>6203 subjects were randomized to receive TIV (N = 4137) or placebo (N = 2066). The sample size was based on an assumed attack rate of 4% which provided 90% power to reject the hypothesis that vaccine efficacy (VE) was ≥ 45%. Cases of influenza like illness (defined as fever (oral temperature ≥37.8°C) plus cough and/or sore throat) were identified both by active (biweekly phone contact) and passive (self reporting) surveillance and nasal and throat swabs were collected from subjects for viral culture.</p> <p>Results</p> <p>TIV was well tolerated and induced a good immune response. The 2005/2006 influenza season was exceptionally mild in the study area, as it was throughout Europe, and only 46 culture-confirmed cases were found in the study cohort (10 influenza A and 36 influenza B). Furthermore among the B isolates, 35 were identified as B/Hong Kong 330/2001-like (B/Victoria/2/87 lineage) which is antigenically unrelated to the vaccine B strain (B/Yamagata/16/88 lineage). The attack rate in the vaccine group (0.7%) was not statistically significantly different from the attack rate in the placebo group (0.9%).</p> <p>Conclusion</p> <p>Due to the atypical nature of the influenza season during this study we were unable to assess TIV efficacy. This experience illustrates the challenge of conducting a prospective influenza vaccine efficacy trial during a single season when influenza attack rates and drift in circulating strains or B virus lineage match can be difficult to estimate in advance.</p> <p>Trial Registration</p> <p>Clinical trial registery: NCT00197223.</p
The Australian Work Exposures Study: Prevalence of Occupational Exposure to Formaldehyde
INTRODUCTION: The aims of this study were to produce a population-based estimate of the prevalence of work-related exposure to formaldehyde, to identify the main circumstances of exposure and to describe the use of workplace control measures designed to decrease those exposures. METHODS: The analysis used data from the Australian Workplace Exposures Study, a nationwide telephone survey, which investigated the current prevalence and exposure circumstances of work-related exposure to 38 known or suspected carcinogens, including formaldehyde, among Australian workers aged 18-65 years. Using the web-based tool OccIDEAS, semi-quantitative information was collected about exposures in the current job held by the respondent. Questions were addressed primarily at tasks undertaken rather than about self-reported exposures. RESULTS: Of the 4993 included respondents, 124 (2.5%) were identified as probably being exposed to formaldehyde in the course of their work [extrapolated to 2.6% of the Australian working population-265 000 (95% confidence interval 221 000-316 000) workers]. Most (87.1%) were male. About half worked in technical and trades occupations. In terms of industry, about half worked in the construction industry. The main circumstances of exposure were working with particle board or plywood typically through carpentry work, building maintenance, or sanding prior to painting; with the more common of other exposures circumstances being firefighters involved in fighting fires, fire overhaul, and clean-up or back-burning; and health workers using formaldehyde when sterilizing equipment or in a pathology laboratory setting. The use of control measures was inconsistent. CONCLUSION: Workers are exposed to formaldehyde in many different occupational circumstances. Information on the exposure circumstances can be used to support decisions on appropriate priorities for intervention and control of occupational exposure to formaldehyde, and estimates of burden of cancer arising from occupational exposure to formaldehyde
Alcohol and Substance Misuse in the Construction Industry
The study investigates the factors contributing to the menace of Alcohol and Substance Misuse (ASM) in the construction industry, and its mitigation. Sequential exploratory mixed method design, involving interview and questionnaire were used for collecting data that were subsequently analysed using thematic analysis, factor analysis and Kruskal-Wallis test. Findings suggest that the problem of ASM is largely caused and exacerbated by mental strain, site working conditions, male dominance and ineffective HR management. Screening and educational approaches were confirmed as the carrot and stick methods for mitigating the menace in the construction industry. The finding implies that by making construction companies more accountable for the wellbeing of their workers, a change could be brought in the industry. These changes could be incentivised by initiatives like PREVENT to mitigate the crisis currently endemic in construction. The study suggests some practical measures for tackling the menace of ASM that is bedevilling the constructio
Gender, risk and the Wall Street alpha male
From the outset, analyses of the 2008 financial crisis, in mainstream as well as feminist discussions, have been gendered. In particular, rampant risk taking in an unregulated environment, widely deemed to be a principle cause of the crash, has been associated with masculine characteristics. In this article I explore how the concepts of gender and risk entwine in two films on the financial crisis – The Other Guys and Margin Call. By looking at how gender is used to dramatise financial risk, I explore how understandings of high risk behaviour are gendered, and the implications this has in the context of finance. Fictional representations mediate public understanding of this notoriously complex field, as the number of films and documentaries on the crisis demonstrates. Exploring how gender is used to communicate risk reminds us that risk taking is part of a performance of masculinity that needs to be established by constructing a feminine, risk-averse other. The contention of this paper is that to address gender bias in finance and the economy, gendered meanings of risk need to be openly challenged, and cultural and material analyses of gendered inequality brought into dialogue
Minority environmental activism in Britain: From brixton to the lake district
Historically, the British environmental movement has been devoid of minority participation, but this is changing very slowly, with the emergence of ethnic minority environmental groups and multiracial environmental alliances. These groups have argued that ethnic minorities have little or no access to public funds earmarked for countryside and wildlife preservation issues. They argue that white environmental organizations do not pay attention to the needs of inner-city minority residents and minority access to the countryside. Increased access, community improvement and beautification projects, environmental education, youth training, community garden projects, and issues of environmental racism are all foci of ethnic minority environmental movements. While some white environmentalists have been supportive of them, others have been uncomfortable with them or even hostile to their existence.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43549/1/11133_2004_Article_BF00990102.pd
Improved prosthetic hand control with concurrent use of myoelectric and inertial measurements
Abstract Background Myoelectric pattern recognition systems can decode movement intention to drive upper-limb prostheses. Despite recent advances in academic research, the commercial adoption of such systems remains low. This limitation is mainly due to the lack of classification robustness and a simultaneous requirement for a large number of electromyogram (EMG) electrodes. We propose to address these two issues by using a multi-modal approach which combines surface electromyography (sEMG) with inertial measurements (IMs) and an appropriate training data collection paradigm. We demonstrate that this can significantly improve classification performance as compared to conventional techniques exclusively based on sEMG signals. Methods We collected and analyzed a large dataset comprising recordings with 20 able-bodied and two amputee participants executing 40 movements. Additionally, we conducted a novel real-time prosthetic hand control experiment with 11 able-bodied subjects and an amputee by using a state-of-the-art commercial prosthetic hand. A systematic performance comparison was carried out to investigate the potential benefit of incorporating IMs in prosthetic hand control. Results The inclusion of IM data improved performance significantly, by increasing classification accuracy (CA) in the offline analysis and improving completion rates (CRs) in the real-time experiment. Our findings were consistent across able-bodied and amputee subjects. Integrating the sEMG electrodes and IM sensors within a single sensor package enabled us to achieve high-level performance by using on average 4-6 sensors. Conclusions The results from our experiments suggest that IMs can form an excellent complimentary source signal for upper-limb myoelectric prostheses. We trust that multi-modal control solutions have the potential of improving the usability of upper-extremity prostheses in real-life applications
- …