Development and Validation of the Self-report Ergonomic Assessment Tool (SEAT)

Despite considerable advances in the practice of office ergonomics, office workers are still suffering from musculoskeletal disorders (MSDs). These disorders, like carpal tunnel syndrome, can lead to high medical costs for employers and intense pain and discomfort for employees. The design of software office workers use could be a contributing factor to their risk of developing MSDs and a tool sensitive enough for evaluating ergonomic risks associated with the design of software is needed. Presented here are the results of a series of three studies focused on the development, improvement, and validation of a Self-report Ergonomic Assessment Tool (SEAT). The SEAT was found to comprise two important factors, stress and strain, and was found to be sufficiently consistent and sensitive to the exertions and postures related to office work. Data from two studies were used to validate stress components of the SEAT, e.g., postures, by using recorded videos and comparing participants’ responses on the SEAT to those of trained raters. Results showed that participants were unable to reliably self-report stressors. Data from one study was used to validate the strain components of the SEAT by comparing participants’ self-reported discomforts to muscle activity measured via surface electromyography and muscle oxygenation measured via near infrared spectroscopy. Participants’ self-reported discomfort did correlate with these physiological measures, however, important exceptions revealed opportunities for future development and testing of the SEAT

The effects of various parameter combinations in parameter-mapping sonifications

Presented at the 21st International Conference on Auditory Display (ICAD2015), July 6-10, 2015, Graz, Styria, Austria.This study will be investigating the design of parametermapping sonifications and investigating how different combinations of sound parameter mappings affect the user’s ability to understand and interpret sEMG data. The parameter mappings being used are all redundantly mapped and the specific parameter combinations are 1) pitch and loudness, 2) pitch, loudness, and attack time, and 3) loudness and attack time. There will be both spatialized (right and left) and nonspatialized versions of each of these mappings. These mappings will be used to present sonifications of two channels of sEMG data to participants to explore if they can identify muscle activation order (which muscle activates first) and relative muscle exertion levels (which muscle has a higher exertion). It is expected that participants will perform better with the spatialized mappings. It is also expected that the participants will perform better with the mappings that include attack time because this results in greater timbral variety

Development of an Effective Procedure Writer’s Guide using a Human Factors and Regulatory Compliance Approach

PresentationWell-written procedures are an integral part of any industrial organization for safe operation, managing risks, and continuous improvement. Regulatory bodies around the world require industries to have current, accurate, and appropriate procedures for most processes. Although the importance of procedures is recognized by all industries in general, significant incidents have occurred in the past due to procedural breakdowns. Some of the procedural breakdowns come from obvious problems such as the procedure not being available or the procedure being wrong. However, some incidents have occurred when correct procedures were available and the operator used those procedures. In these instances, the reason why operators do not follow procedures correctly may be attributable to many factors, one of them being that the procedure is presented or designed in a manner that does not sufficiently communicate to the operators the information that is needed in a manner that is easily and quickly understood. The work presented here is focused on the latter circumstance and is part of a program of research that will ultimately lead to the development of a writer’s guide for procedures that supports operators’ comprehension and compliance with all types of industrial procedures. The writer’s guide is based on empirical findings from human factors and human performance studies and provides writers with information on how to present procedures in a manner that is clear, thorough, and (if necessary) implementable with short notice. For the first phase of the project, a sample of the regulations and standards from several industries were used to identify procedure writing practices necessary for ensure regulatory compliance. Regulations and industrial standards from around the world were organized to reflect common ideas and the implications in terms of human factors needs were identified with regard to procedure design. Any human factors (HF) that had implications for the writer’s guide that had empirical support, were included in the writer’s guide (with the reference) with an explanation of the HF implication and empirical support. The writer’s guide developed is structured to allow procedure writers access to guidance on various types of procedures they are writing, the type of information they are trying to communicate, and methods for maintaining accurate and current procedures. As mentioned, the current project is the beginning of a program of research and then next phase will include feedback from operators regarding the challenges they face when using procedures

Sonification Synthesizer for Surface Electromyography

Presented at the 20th International Conference on Auditory Display (ICAD2014), June 22-25, 2014, New York, NY.Surface electromyography (sEMG) is a means for measuring muscle activity. sEMG data are typically displayed graphically on a computer screen and while this can be a useful way to display the data, it is not always ideal. This extended abstract details the development of a sonification tool that allows users to sonify sEMG data in real-time. The tool will allow the user to independently control the sound of each channel, similar to a software synthesizer. Independent real-time control of each channel will allow the user to create sonification models, which are mappings of certain sounds to specific muscle groups. A prototype of the tool is currently being developed using SuperCollider in parallel with a Delsys Trigno Wireless sEMG system. This tool will allow users to easily explore various kinds of sEMG sonification models and test them for intuitiveness and effectiveness

Landau levels in the case of two degenerate coupled bands: kagome lattice tight-binding spectrum

The spectrum of charged particles hopping on a kagome lattice in a uniform transverse magnetic field shows an unusual set of Landau levels at low field. They are unusual in two respects: the lowest Landau levels are paramagnetic so their energies decrease linearly with increasing field magnitude, and the spacings between the levels are not equal. These features are shown to follow from the degeneracy of the energy bands in zero magnetic field. We give a general discussion of Landau levels in the case of two degenerate bands, and show how the kagome lattice tight-binding model includes one special case of this more general problem. We also discuss the consequences of this for the behavior of the critical temperature of a kagome grid superconducting wire network, which is the experimental system that originally motivated this work.Comment: 18 pages, 8 figure

Acoustic Emission from crumpling paper

From magnetic systems to the crust of the earth, many physical systems that exibit a multiplicty of metastable states emit pulses with a broad power law distribution in energy. Digital audio recordings reveal that paper being crumpled, a system that can be easily held in hand, is such a system. Crumpling paper both using the traditional hand method and a novel cylindrical geometry uncovered a power law distribution of pulse energies spanning at least two decades: (exponent 1.3 - 1.6) Crumpling initally flat sheets into a compact ball (strong crumpling), we found little or no evidence that the energy distribution varied systematically over time or the size of the sheet. When we applied repetitive small deformations (weak crumpling) to sheets which had been previously folded along a regular grid, we found no systematic dependence on the grid spacing. Our results suggest that the pulse energy depends only weakly on the size of the paper regions responsible for sound production.Comment: 12 pages of text, 9 figures, submitted to Phys. Rev. E, additional information availible at http://www.msc.cornell.edu/~houle/crumpling

Dopamine and memory dedifferentiation in aging.

The dedifferentiation theory of aging proposes that a reduction in the specificity of neural representations causes declines in complex cognition as people get older, and may reflect a reduction in dopaminergic signaling. The present pharmacological fMRI study investigated episodic memory-related dedifferentiation in young and older adults, and its relation to dopaminergic function, using a randomized placebo-controlled double-blind crossover design with the agonist Bromocriptine (1.25mg) and the antagonist Sulpiride (400mg). We used multi-voxel pattern analysis to measure memory specificity: the degree to which distributed patterns of activity distinguishing two different task contexts during an encoding phase are reinstated during memory retrieval. As predicted, memory specificity was reduced in older adults in prefrontal cortex and in hippocampus, consistent with an impact of neural dedifferentiation on episodic memory representations. There was also a linear age-dependent dopaminergic modulation of memory specificity in hippocampus reflecting a relative boost to memory specificity on Bromocriptine in older adults whose memory was poorer at baseline, and a relative boost on Sulpiride in older better performers, compared to the young. This differed from generalized effects of both agents on task specificity in the encoding phase. The results demonstrate a link between aging, dopaminergic function and dedifferentiation in the hippocampus.This research was funded mainly by a Fellowship to AMM from Research into Ageing, UK, and by an RCUK Academic Fellowship at the University of Edinburgh. Some of the research was conducted by Hunar Abdulrahman as part of a dissertation for the MSc in Neurosciences at the University of Edinburgh. The research was also supported by a Human Brain Project grant from the National Institute of Mental Health and the National Institute of Biomedical Imaging & Bioengineering. PCF was supported by a Wellcome Trust Senior Fellowship in Clinical Science, and by the Bernard Wolfe Health Neuroscience Fund. ETB is a part-time (50%) employee and shareholder of GSK. AMM is a member of the University of Edinburgh Centre for Cognitive Ageing and Cognitive Epidemiology, part of the cross-council Lifelong Health and Wellbeing Initiative, Grant number G0700704/84698.This is the accepted manuscript. The final version is available at http://dx.doi.org/10.1016/j.neuroimage.2015.03.03