International Journal of Industrial Ergonomics最新文献

Scientific and rational visual training is an important way to avoid visual problems in the elderly. Current visual ability training suffers from a small range of users and low participation, and few studies have focused on the motivation of older users to participate in training and whether there are differences in motivation between older users and users of other age groups. This study investigated the factors influencing the willingness to use visual ability training applications in terms of both user motivation and behavioral ability and constructed a hypothesis model based on ARCS motivation theory and the Fogg Behavior model (FBM). To see if there were differences in influencing factors among users from different backgrounds, four moderating variables were introduced: age, gender, education level, and self-assessment of visual ability. All the design strategies involved are then presented in a storyboard format. 192 participants viewed the storyboard and completed the corresponding questionnaire on their willingness to use visual ability training. The findings show that attention has a significant positive effect on satisfaction and an indirect positive effect on the willingness to use. Satisfaction and behavioral competence had a significant positive effect on willingness to use. Age, gender, education level, and self-rated visual ability had moderating effects in the influence factor model. This study can provide a reference for the design of visual training applications for the elderly to enhance users' willingness to use them.

The study explores the effects of display technique, target size, and complexity of the background on searching accuracy, eye tracking performance, visual fatigue, and presence. Twenty-five participants were recruited in the experiment, where two types of display technique (2D, 3D), two types of background complexity (low, high), and two types of target size (200 × 200 pixels, 60 × 60 pixels) were examined on accuracy, fixation time, numbers of fixations, Simulator Sickness Questionnaire (SSQ), and iGroup Presence Questionnaire (IPQ). The results indicated that display technique was significant on accuracy, fixation time, number of fixations, and SSQ. Though having inferior performance in accuracy and SSQ than 2D, 3D demonstrated better performance in the number of fixations and fixation time. Background complexity was significant on accuracy and IPQ, while low complexity has a better performance than that in accuracy and IPQ. Target size was significant in accuracy, where the accuracy of 200 × 200 pixels was better than that of 60 × 60 pixels. From the analysis of area of interest (AOI), participants tended to fix on revised pictures as compared with original pictures. The results of this study could serve as a reference for game manufacturers to design a 3D “Spot The Difference” game in the future.

Musculoskeletal disorders (MSDs) have a complex aetiology. How to lift training (HTLT) does not address this complexity, is an ineffective prevention strategy but remains widely utilised. This study explores the extent to which HTLT is utilised and the beliefs of employers and work health and safety (WHS) providers to this approach as an MSD prevention strategy.

Method

An online questionnaire was distributed to employers and WHS providers to collect quantitative and qualitative information on the extent to which HTLT was being used and the beliefs about its use in MSD prevention.

Results

A total of 1507 responses were analysed (1271 employers, 236 WHS providers). Over 70% of participants had used HTLT in an MSD prevention program in the past 2 years. For employers the belief that HTLT is necessary under WHS legislation (OR 1.755, CI 1.135,2.712) was associated with the use of HTLT. For providers, the belief that HTLT is necessary for MSD prevention programs (OR 1.57 CI 1.10, 2.25) or if the service was requested (OR 3.88 CI 1.78,8.45) were associated with HTLT delivery.

Conclusions

HTLT remains highly prevalent in MSD prevention despite strong evidence that lifting training is ineffective and does not address WHS legislative requirements. Strategies to reduce HTLT use industry and utilise more effective MSD risk management controls will need to bridge the research evidence to practice gap and use implementation science principles to improve the uptake of evidence-based interventions which take a comprehensive systems-based approach to MSD prevention.

A laboratory experiment evaluated local muscle fatigue development in the neck extensor muscles during prolonged smartphone use in sitting. Twenty young adults conducted a smartphone task for 45 min in supported sitting, with the mean head tilt angle of 30.4°–34.6° from neutral upright. The mean amplitude and median power frequency of the electromyography (EMG) signals of the cervical erector spinae muscles were quantified during the smartphone task and in intermittent sub-maximal isometric neck extension trials. Data showed an increasing and decreasing trend of the mean amplitude and the median power frequency over time, respectively. Still, the statistical significance of the time effect was not found consistently. The median power frequency of the right neck extensor muscle differed significantly (p < 0.05) between the trials but did not indicate fatigue development. Study results suggest that smartphone use in common supported sitting for 45 min, although subjective rated neck discomfort increased significantly, did not produce significant fatigue in the superficial neck extensors. Investigation into the mechanism of neck discomfort due to intensive smartphone use would require a comprehensive evaluation of time-dependent changes in the passive tissues and synergistic activation of deeper cervical spine muscles.

Color has considerable effects on physiological and psychological perception during human-machine interaction. However, previous studies either compared whole sets of color schemes or only looked at single colors. This paper quantitively explored the physio-psychological underpinnings of the perceptual overload problem brought on by excessive color quantity involving expanding variety of colors and chromatic areas. Further, we applied the Gestalt Similarity law to determine if color grouping could improve visual perception. Twenty-two participants viewed color stimuli with their brain activity, subjective emotional experience, and visual discomfort being measured, reflecting three aspects of visual perception. The time-frequency analysis on electroencephalographic (EEG) revealed that increasing color quantity caused a boosted activation of delta, theta, and gamma bands in the parietal and occipital lobes, consistent with higher subjective emotional arousal. Color Gestalt substantially decreased the intensity of visual cortex activity and emotional arousal while enhancing visual comfort. The present Similarity grouping method, in that colors are different in saturation and brightness but identical in hue, broadened the grouping criteria in previous Gestalt research that employed identical colors.

Procrastination is a prevalent phenomenon among students in higher education that results in negative consequences. Past research investigated the changes in students' procrastination primarily in face-to-face settings and reported mixed findings relying on self-reported questionnaires and discrete measurements such as submission times. In this study, we build on this research, considering both face-to-face and online learning environments when investigating changes in procrastination over an academic term. To quantify individuals' procrastination, we use deadline reactivity, an individual's tendency to procrastinate based on longitudinal data, and time proximity of submission to deadline based on discrete data. We find the significant main effect of time in the academic term on deadline reactivity and time proximity of submission to deadline, indicating that in both the face-to-face and online learning environments, students' procrastination increases as the term progresses. We also construct predictive models of deadline reactivity that could be estimated with the time proximity of submission to deadline, learning environments, and time in the academic term. Our results suggest that the instructors' efforts to intervene in students' procrastination would be more required in the second half of the academic term when procrastination is highest.

Virtual reality can simulate virtual heights and increase postural sway, while adding a cognitive task has a potential stabilization effect on posture stability. Our purpose was to observe the change of postural steadiness in different virtual heights, with or without an added-on cognitive task. Thirty young and healthy participants completed standing tasks in the real world and three virtual heights with or without a concurrent simple reaction time (SRT) task in a virtual environment. Most of the center of pressure parameters significantly increased while standing without an SRT task at virtual heights compared with the real world, but this difference was not observed while standing with an SRT task. The height-dependent effect for postural steadiness was not documented. Perceived distress scores were generally low and increased at exposure to the 12-m height compared to the 0-m height. There was no difference in SRT at the three virtual heights. Our results documented a destabilizing effect of a virtual environment, but were not able to confirm a height-dependent effect. A concurrent SRT task increased steadiness in virtual environment, and might have potentials being used as a training approach to enhance postural steadiness for at-height workers.

The emergence of exoskeletons has opened new opportunities to reduce back injuries in the construction industry. Perspectives of construction stakeholders regarding factors that influence adoption of exoskeletons, would inform successful implementation of exoskeletons in the construction industry. This study aims to understand factors that are critical for the adoption of back-support exoskeletons in the construction industry. Industry practitioners were surveyed to identify the important stakeholders whose perspectives are critical to decisions regarding the adoption of exoskeletons. The survey also identifies the factors that could influence the implementation of exoskeletons in the construction industry. Analytical hierarchy process was employed to evaluate and rank the factors. Informed by the survey results, two focus groups were conducted to understand how the factors influence the implementation process. The results identified construction workers, supervisors, regulatory bodies, ergonomists, corporate management, and safety professionals as the key stakeholders for exoskeleton adoption in the construction industry. Exoskeleton features such as usability, durability, long-term benefits and compatibility with work tasks are the most important facilitators, whereas catch and snag risks, fit, weight, and cost justification are the most critical barriers. The focus group discussions highlighted the benefits and applications of back-support exoskeletons, design modifications to exoskeletons, and challenges to adopting exoskeletons in the construction industry. Construction companies could leverage these findings to develop exoskeleton implementation strategies. Researchers and designers could use the design modifications to improve adaptability of exoskeletons for construction work. This study contributes to the socio-technical systems theory by defining key decision-makers and factors influencing exoskeleton adoption.

Background

Work in the slaughterhouse industry increase the risk of shoulder disorders due to high occupational mechanical exposures. Assistive devices, such as exoskeletons, have been developed to reduce the mechanical exposures, but few studies have investigated exoskeleton's feasibility, when used in a workplace setting.

Objectives

The objective was to explore managers' and workers' expectations and experiences related to using a shoulder exoskeleton, and to evaluate its feasibility compared to an existing assistive device (a ‘lifting glove’) at a Danish slaughterhouse.

Participants

The participants included 26 production line workers and their managers at a packaging department at a large slaughterhouse facility.

Methods

In a 5-month field study, data on worker's expectations and experiences of using a shoulder exoskeleton, was compared to a lifting glove and to working without any assistive device. Data was collected using semi-structured interviews, questionnaires, and on-site observations.

Results

Expectations were that shoulder exoskeletons would reduce the mechanical exposure and strain in workers. Some managers also expected that workers could handle more weight/produce more and that the need for job rotation could be reduced. Workers reported the exoskeleton to ‘straighten the body’, and reduced strain, but e others experienced no perceived support or found donning and doffing too time consuming.

Conclusion

We found different expectations as to what the shoulder exoskeleton should achieve. This could influence the evaluation of the feasibility of using a shoulder exoskeleton in slaughterhouse work. To facilitate the feasibility of exoskeletons it is important to explicate different expectations and to allow for individual tailoring in its implementation.

The occurrence of work-related musculoskeletal disorders (WMSDs) is influenced by various factors and significantly impacts workers' mobility and flexibility. However, the degrees of influence and the relationship of the influencing factors with WMSDs remain unclear. Therefore, it is quite important to propose a comprehensive analysis of underlying factors of WMSDs from a system perspective. In this study, we utilize a meta-analytic approach to conduct a comprehensive analysis. Specifically, we extend the Biological-psychological-social (BPS) model to investigate the main factors of WMSDs, thus illuminating the associations between these factors and their varying degrees of influence on WMSDs. Through a combination of qualitative development and quantitative meta-analysis, we propose a specific BPS model tailored to WMSDs. Our BPS model encompasses three main factors: psychological, social, and biological, and the biological factor is further categorized into adjustable and fixed sub-factors. The modeling results demonstrate that social factor and fixed biological factor are the main aspects that have a significant influence on WMSDs, while psychological factor mainly regulate the effect of adjustable biological factor on WMSD. Social factor also has a mediating effect between biological factors and WMSDs. Our study reveals interactions among biological, psychological, and social factors, and provides comprehensive and holistic guidance for WMSD prevention and intervention based on the extended BPS model. Moreover, we offer actionable suggestions for WMSD intervention. This research contributes to a deeper understanding of WMSDs and provides valuable insights for designing effective preventive measures and interventions to mitigate the impact of WMSDs on workers’ health and well-being.