The impact of tool selection on back and wrist injury risk in tying steel reinforcement bars: a single case experiment

The paper explores the risk of work-related musculoskeletal injury in tying steel reinforcement bars. Three tools are compared to determine the extent to which ergonomic tools can reduce the risk of injury to the back and wrist in steel-tying. A whole body system of wearable sensors was used to measure biomechanical risk in tying. Three tools were assessed to determine their impact on the risk of work-related musculoskeletal injury when used at different heights. These were: a conventional pincer-cutting tool; a power-driven tying tool, and a long handled stapler tool. No tool was found to work best in all situations. The long handled stapler tool significantly reduced trunk inclination when used from ground to shoulder height, but produced higher trunk extension (backward bending) when used above shoulder height. The power tying tool did not reduce the need to bend when working at lower work heights. The power-tying tool produced significantly lower peak wrist flexion values compared to the conventional pincer-cutter tool at all work heights except overhead. The power tying tool involved significantly lower levels of wrist rotation than the conventional pincer-cutter tool at all work heights above knee level. Many assessments of ergonomic risk factors in construction rely on observational methods. The use of small, lightweight wearable sensors permits the objective measurement of biomechanical risk factors for work-related musculoskeletal injury, as well as providing objective performance data that can be used in the design and selection of task-specific tools. Our analysis of work by height also provides insight into the way in which risk factors and reduction opportunities afforded by different tools vary depending on the height at which work is to be performed

The impact of tool selection on back and wrist injury risk in tying steel reinforcement bars: a single case experiment

The paper explores the risk of work-related musculoskeletal injury in tying steel reinforcement bars. Three tools are compared to determine the extent to which ergonomic tools can reduce the risk of injury to the back and wrist in steel-tying. A whole body system of wearable sensors was used to measure biomechanical risk in tying. Three tools were assessed to determine their impact on the risk of work-related musculoskeletal injury when used at different heights. These were: a conventional pincer-cutting tool; a power-driven tying tool, and a long handled stapler tool. No tool was found to work best in all situations. The long handled stapler tool significantly reduced trunk inclination when used from ground to shoulder height, but produced higher trunk extension (backward bending) when used above shoulder height. The power tying tool did not reduce the need to bend when working at lower work heights. The power-tying tool produced significantly lower peak wrist flexion values compared to the conventional pincer-cutter tool at all work heights except overhead. The power tying tool involved significantly lower levels of wrist rotation than the conventional pincer-cutter tool at all work heights above knee level. Many assessments of ergonomic risk factors in construction rely on observational methods. The use of small, lightweight wearable sensors permits the objective measurement of biomechanical risk factors for work-related musculoskeletal injury, as well as providing objective performance data that can be used in the design and selection of task-specific tools. Our analysis of work by height also provides insight into the way in which risk factors and reduction opportunities afforded by different tools vary depending on the height at which work is to be performed

Flexible Sensors for Pressure Therapy: Effect of Substrate Curvature and Stiffness on Sensor Performance.

Flexible pressure sensors are increasingly being used in medical and non-medical applications, and particularly in innovative health monitoring. Their efficacy in medical applications such as compression therapy depends on the accuracy and repeatability of their output, which in turn depend on factors such as sensor type, shape, pressure range, and conformability of the sensor to the body surface. Numerous researchers have examined the effects of sensor type and shape, but little information is available on the effect of human body parameters such as support surfaces' curvature and the stiffness of soft tissues on pressure sensing performance. We investigated the effects of body parameters on the performance of pressure sensors using a custom-made human-leg-like test setup. Pressure sensing parameters such as accuracy, drift and repeatability were determined in both static (eight hours continuous pressure) and dynamic (10 cycles of pressure application of 30 s duration) testing conditions. The testing was performed with a focus on compression therapy application for venous leg ulcer treatments, and was conducted in a low-pressure range of 20-70 mmHg. Commercially available sensors manufactured by Peratech and Sensitronics were used under various loading conditions to determine the influence of stiffness and curvature. Flat rigid, flat soft silicone and three cylindrical silicone surfaces of radii of curvature of 3.5 cm, 5.5 cm and 6.5 cm were used as substrates under the sensors. The Peratech sensor averaged 94% accuracy for both static and dynamic measurements on all substrates; the Sensitronics sensor averaged 88% accuracy. The Peratech sensor displayed moderate variations and the Sensitronics sensor large variations in output pressure readings depending on the underlying test surface, both of which were reduced markedly by individual pressure calibration for surface type. Sensor choice and need for calibration to surface type are important considerations for their application in healthcare monitoring

Evaluation of Flexible Force Sensors for Pressure Monitoring in Treatment of Chronic Venous Disorders.

The recent use of graduated compression therapy for treatment of chronic venous disorders such as leg ulcers and oedema has led to considerable research interest in flexible and low-cost force sensors. Properly applied low pressure during compression therapy can substantially improve the treatment of chronic venous disorders. However, achievement of the recommended low pressure levels and its accurate determination in real-life conditions is still a challenge. Several thin and flexible force sensors, which can also function as pressure sensors, are commercially available, but their real-life sensing performance has not been evaluated. Moreover, no researchers have reported information on sensor performance during static and dynamic loading within the realistic test conditions required for compression therapy. This research investigated the sensing performance of five low-cost commercial pressure sensors on a human-leg-like test apparatus and presents quantitative results on the accuracy and drift behaviour of these sensors in both static and dynamic conditions required for compression therapy. Extensive experimental work on this new human-leg-like test setup demonstrated its utility for evaluating the sensors. Results showed variation in static and dynamic sensing performance, including accuracy and drift characteristics. Only one commercially available pressure sensor was found to reliably deliver accuracy of 95% and above for all three test pressure points of 30, 50 and 70 mmHg

Critical design aspects of maternity support-garments and its contemporary perspective

This study aims to understand the needs of plus-size pregnant women and critical design aspects for a pregnancy support garment and to emphasize the importance of inclusive design in this important product category.The research examines the historical and societal connotations of maternity and the changes in support garment design associated with changes in the perception of the modern plus size Madonna. At the same time, it analyses the state-of-the-art in modern maternity support garments and examines data, gathered through a pilot online survey.

Motorcycle protective clothing: physiological and perceptual barriers to its summer use

Despite strong evidence of protective benefits, thermal discomfort is a key disincentive to motorcyclists wearing protective clothing in hot conditions. This paper presents some findings from our studies concerning the thermal management properties of motorcycle protective clothing and their physiological impact in hot conditions. The thermal and vapour permeability and abrasion resistance properties of motorcycle protective clothing were investigated in laboratory tests. The physiological and cognitive impact on humans was investigated using objective and subjective measures under controlled climate conditions and in a real-world riding trial. The aims were to determine: (i) if associations existed between thermal management and the abrasion-resistance properties of a range of commonly available, all-season motorcycle protective suits, (ii) the extent of the thermal load imposed by motorcycle clothing worn in average Australian summer conditions, and (iii) the impact of that thermal burden on psychophysical function. The results demonstrated significant physiological strain for motorcyclists wearing protective clothing in hot conditions. Wide variations in the thermal characteristics and abrasion resistance properties of the suits tested were identified. Ongoing work is investigating the impact that elevated thermal discomfort and physiological thermal strain can have on riding performance and the potential for clothing features, such as ventilation ports to reduce thermal discomfort. These results will determine thresholds for the thermal qualities of motorcycle clothing required for an acceptable compromise between user comfort and injury protection. The outcome will inform industry and consumer information programs about the performance required of motorcycle protective clothing suitable for use in hot conditions

Influence of Fabric Structural Attributes on Their Aerodynamic Behavior

ABSTRACT The aerodynamic properties of 15 knitted fabrics of varying cover factor, yarn, and fiber compositions were investigated for their aerodynamic properties on circular cylinders in a wind tunnel. Measurements of the drag force, pressure distribution, and the Particle Image Velocimetry (PIV) technique were used in order to obtain a better understanding of the effects of yarn, fiber composition, cover factor, and elastic deformation on the flow field and drag coefficient. It was clearly demonstrated from the drag force measurements that the yarn construction and fiber composition have a substantial effect on the drag coefficient (C D ), with fabrics composed of spun yarn experiencing no C D -drop as opposed to those composed of filament yarn, and being almost unaffected by the cover factor in the range of Reynolds numbers investigated. Hairiness of the spun yarn was found to minimise the drag-reducing effect of the boundary layer transition and increase the trans-critical drag. The hairy surface layer also appeared to retard the turbulent boundary layer as almost no pressure recovery was observed prior to separation on the cylinder model. The effect of elastic deformation was investigated by image analysis of scanned textile samples, and demonstrated that surface roughness might not be directly correlated to cover factor when the fabrics are stretched. Different elastic behavior of fabrics with different cover factors was also found to affect the structure of the knit surface and thus their aerodynamic behavior. The onset of drag crisis found in drag measurements confirmed the deviation from a sequence determined solely by cover factor

Motorcycle protective clothing: physiological and perceptual barriers to their summer use

Despite strong evidence of protective benefits, thermal discomfort is a key disincentiveto motorcyclists wearing protective clothing in hot conditions. This paper presentssome findings from our studies concerning the thermal management properties ofmotorcycle protective clothing and their physiological impact in hot conditions.The thermal and vapour permeability and abrasion resistance properties of motorcycleprotective clothing were investigated in laboratory tests. The physiological andcognitive impact on humans was investigated using objective and subjective measuresunder controlled climate conditions and in a real-world riding trial. The aims were todetermine: (i) if associations existed between thermal management and the abrasionresistanceproperties of a range of commonly available, all-season motorcycleprotective suits, (ii) the extent of the thermal load imposed by motorcycle clothing wornin average Australian summer conditions, and (iii) the impact of that thermal burden onpsychophysical function.The results demonstrated significant physiological strain for motorcyclists wearingprotective clothing in hot conditions. Wide variations in the thermal characteristics andabrasion resistance properties of the suits tested were identified. Ongoing work isinvestigating the impact that elevated thermal discomfort and physiological thermalstrain can have on riding performance and the potential for clothing features, such asventilation ports to reduce thermal discomfort. These results will determine thresholdsfor the thermal qualities of motorcycle clothing required for an acceptable compromisebetween user comfort and injury protection. The outcome will inform industry andconsumer information programs about the performance required of motorcycleprotective clothing suitable for use in hot conditions

Generalised growth models for aquatic species with an application to blacklip abalone (Haliotis rubra)

This paper presents a maximum likelihood method for estimating growth parameters for an aquatic species that incorporates growth covariates, and takes into consideration multiple tag-recapture data. Individual variability in asymptotic length, age-at-tagging, and measurement error are also considered in the model structure. Using distribution theory, the log-likelihood function is derived under a generalised framework for the von Bertalanffy and Gompertz growth models. Due to the generality of the derivation, covariate effects can be included for both models with seasonality and tagging effects investigated. Method robustness is established via comparison with the Fabens, improved Fabens, James and a non-linear mixed-effects growth models, with the maximum likelihood method performing the best. The method is illustrated further with an application to blacklip abalone ( Haliotis rubra) for which a strong growth-retarding tagging effect that persisted for several months was detected

Examination of the effects of a new compression garment on skin tissue oxygenation in healthy volunteers

Objective: Compression devices have been shown to reduce venous stasis, increase blood flow and skin tissue oxygenation (StO2), promoting healthy tissue. This study aimed to explore the efficacy of a new compression garment in three different positions in healthy adults. Methods: In this quantitative study, potential participants were screened and recruited using the Physical Activity Readiness Questionnaire (PAR-Q, Canada). Participants attended three separate, one-hour sessions to evaluate StO2 in supine-lying, chair-sitting and long-sitting positions. StO2 was recorded for 20 minutes pre-, during and post- a 20-minute intervention using a compression garment, TributeWrap (Lohmann-Rauscher, Germany). A repeated-measures analysis of variance (ANOVA) was followed by post-hoc pairwise comparisons. Results: A total of 28 healthy volunteers took part (aged 24.6 ±8.4years; 13 males, 15 females). A significant difference was seen between the three positions (p<0.001). Chair-sitting had the lowest StO2 pre-intervention, increasing StO2 significantly (32.25%, p<0.001) during wear of the compression garment (24.8% higher than baseline post-intervention). No significant difference was seen between long sitting and supine-lying (p=1.000). In contrast, long-sitting and supine-lying StO2 was higher pre-intervention compared with chair-sitting and only increased post-intervention (11% and 16.8% respectively, p<0.001) compared with baseline. Conclusion: The compression garment significantly increased StO2 levels in both seating positions. Further studies are required to determine if increasing StO2 through short intervention sessions with this device has the potential to improve self-management of tissue health in individuals with reduced mobility, oedema or venous insufficiency