查看更多>>摘要：This study examined the rest period and object load influence on upper limb muscle strength recovery after a simulated 9 min intermittent repetitive manual work. Eight task conditions consisting of four rest periods (2.25, 4.5, 9, 13.5 min) and two object loads (1 and 2 Kg) were studied. Twelve male subjects were recruited to participate. Four muscles in the right upper limb were tested using surface electromyography. Heart rate and rating of fatigue were measured during the experiment. The experimental results showed that the rest period of 4.5 min, which was not the largest, could be the most efficient recovery level that might result in obtaining better muscle strength recovery and larger heart rate reduction with a shorter rest time. The study results provided fundamental work/rest pattern data that could be considered in early intervention strategies for muscle fatigue prevention at worksites. Limitations and recommendations regarding the current study were highlighted. Relevance to industry: Upper limb repetitive manual load transfer tasks are common at worksites, and can result in work-related musculoskeletal disorders. The results from this study should be useful in work/rest scheduling for repetitive manual load transfer tasks.
查看更多>>摘要：In this research, we examined the impact of icons' depth on user attention and search efficiency during icon recognition. First, 61 participants were asked to view an image composed of flat (2D) and neumorphic (3D) icons arranged in a circle, with their eye movements monitored by an eye tracker. Each participant was asked to watch the pictures carefully then complete four search tasks under the following four conditions (with suitable prompts) while viewing them: selecting a target 2D icon from among 2D icons, selecting a target 3D icon from among 3D icons, selecting a target 2D icon from among mixed 2D and 3D icons, and selecting a target 3D icon from among mixed 2D and 3D icons. The results indicated that 3D icons performed better in terms of attention distribution and attention attraction than 2D icons. There were no significant differences in terms of search time or accuracy between selecting a target 2D icon from among 2D icons and selecting a target 3D icon from among 3D icons, selecting a target 2D icon from among mixed 2D and 3D icons, and selecting a target 3D icon from among mixed 2D and 3D icons. The findings have practical significance for icon design and can provide guidance for designers, prompting them to either use 2D or 3D icons to achieve intentional visual and cognitive effects.
查看更多>>摘要：Heat-related illness (HRI) is a common occupational injury, especially among workers in the construction industry. Methods need to be developed to predict and minimize HRI risk. The objective of this study was to investigate whether differences in heart rate (HR) can be used to predict HRI risk. We surveyed construction workers during the period from May 1 to October 30, 2020. The physiological data of 79 workers were recorded during their working hours for a period of 3163 person-time. The resting HR was defined as the lowest reading taken within the first hour of wearing the sensor, and HRI risk was determined using the following formula: 180 - (0.65 x age). The rate of increase in HR from rest was calculated using the following formula: (maximum HR resting HR)/resting HR. On these 3163 person-time, HRI risk was observed at 368 person-time (11.6%). After analyzing the receiver operating characteristics curve, the cut-off value was 132.9%, with a sensitivity of 75.5% and specificity of 85.0%. Our results showed that the difference in HR from rest is a good indicator for predicting HRI risk. Furthermore, continuous physiological monitoring using a wearable sensor can aid in detecting early signs of HRI risk.
查看更多>>摘要：Musculoskeletal Disorders (MSDs) remain a major concern for workers in the healthcare industry. Healthcare workers are at high risk of work-related MSDs mainly caused by overexertion from manually handling patients. Exoskeletons may be a useful tool to help reduce the risk of MSDs during patient handling. As a review study, we surveyed articles focusing on applying exoskeletons to patient handling tasks specifically. We also reviewed relevant government databases and other studies related to Safe Patient Handling and Mobility (SPHM) programs and exoskeleton applications in general. The exoskeletons specifically designed for patient handling were found to be sparse. To have a better understanding of the needs and challenges of developing and using exoskeletons for reducing risks of work-related MSDs in healthcare workers during patient handling, this critical review (1) provided an overview of the existing issues and projected future burdens related to work-related MSDs during patient handling tasks, (2) recognized current and potential roles and applications of existing exoskeletons, and (3) identified challenges and needs for future exoskeleton products. In conclusion, we do not expect exoskeletons to replace the existing SPHM programs, but rather play a complementary role to these multi-pronged programs. We expect that emerging exoskeleton products can be introduced to uncontrolled or specialized healthcare en-vironments. There are various expectations and requirements for an exoskeleton used in different healthcare settings. Additionally, introducing certain types of exoskeletons for patients to assist them during treatment and rehabilitation may help reduce the MSD risks to the healthcare workers.
查看更多>>摘要：Psychosocial safety behavior has been indicated to be an important factor in ensuring workplace safety, but the forming mechanism of the psychosocial safety behavior of coal miners remains unclear. Considering the important impact of job role demands on psychosocial safety behavior and the dual attributes of job role demands in different contexts, this study constructs a dual hierarchical model of job role demands on psychosocial safety behavior in the coal-mining context, and explains the roles of personal resources (safety-related psychological capital) and job resources (psychosocial safety climate) in this model based on job demands-resources (JD-R) theory. Hierarchical nested data were gathered from 753 coal miners on 50 working teams. The Mplus modelling results demonstrate that job role demands manifesting as job hindrances negatively affect psycho social safety behavior, and safety-related psychological capital mediates this impact. Moreover, as expected, the negative influence of job role demands on safety-related psychological capital and the indirect negative influence of job role demands on psychosocial safety behavior are both inverted to positive in a high-level psychosocial safety climate. The findings support the hindrance influencing mechanism of job role demands on psychosocial safety behavior considering the comprehensive influence of personal resources and job resources in the coal mining context from the psychological perspective. A new management perspective and some intervention recommendations for coal mine work safety at the psychological level are proposed to promote the safety behavior of coal miners, which could then be used as a reference for other high-risk industries.
查看更多>>摘要：The Taiwanese government has implemented a subsidy strategy to encourage the purchase of e-bikes, thus reducing the overall amount of air pollution emitted by fueled vehicles. However, e-bikes are relatively new vehicles that are associated with road safety risks. With increased sales, cycling safety has become an emerging public health challenge. This survey study adopted mental workload measures, including the Driving Activity Load Index (DALI) and Rating Scale Mental Effort (RSME), and used subjective perception measures, including user experiences (UXs) and the feeling of risk, to investigate the factors influencing cycling crashes. We recruited cyclists who visited repair stations to maintain their e-bikes. Results showed that the model constructs of UX pragmatic quality and speed were useful predictors of e-bike crashes in traffic environments. Moreover, the DALI scores showed significant differences at different speed levels, while DALI and anxiety exhibited a highly positive correlation. Respondents who cycled with higher pragmatic quality satisfaction and at speeds less than 25 km/h were less prone to traffic crashes. Further, speed was connected to mental workload and anxiety when riding an e-bike. A mobile self-reporting option is proposed to enhance the engagement of cyclists in road safety while better achieving self-managed vehicle speed.
查看更多>>摘要：Complexity in marine operations requires a robust and dynamic framework for human error assessment to aid safety-based decision making under uncertainty. The current study presents a dynamic Human Factors Analysis and Classification System for Maritime Accident. The model is used for human factor assessment in critical maritime operations, considering the influential factors of dynamic cognitive human behavior and complex interactions among core risk factors. The HFACS-MA structure consists of five levels of human factors based on the International Maritime Organization (IMO) guiding principles and the Human Factor Analysis and Classification System (HFACS) concept. Based on three accident case studies, the study explores five levels of human role to develop a robust model structure for critical maritime operations. The developed structure is translated into a novel Bayesian network (BN) structure, capturing the dependencies among the risk influencing factors for the three accident scenarios. The developed model framework for the accident scenarios emphasizes the changing characteristics of human performance influential factors and the dynamic operating environment. The demonstrated case studies further confirm the model adaptiveness in human factor assessment, considering the dynamic decision-making influential factors and operational uncertainty.
查看更多>>摘要：There has been a recent advent in the use of wearable devices in the workplace as these technologies offer an opportunity to track product movement through the warehousing and material handling process. This study examines the use of a wand scanner and two wearable devices (ring scanner and smart glasses) on forty healthy participants to study comfort, discomfort and performance while executing shipment putting tasks. The impact of wearables was investigated using the Comfort Rating Scales and Body Discomfort Scale. Participants identified the ring and wand scanner as the most comfortable device. Participants became more uncomfortable using the smart glasses over time during the completion of the task. While using the glasses, the participants experienced discomfort in the eye, neck, and shoulder. This research shows that there is a need for additional improvement with smart glasses before incorporating this technology into the workplace. Companies contemplating incorporating smart glasses to improve productivity can use the results of this study to identify important features needed to optimize this device. Likewise, companies interested in shifting away from handheld scanning technologies to wearable solutions can consider ring scanners and similarly donned devices as performance enhancing solutions. Relevance to industry: This study investigates productivity, comfort, and discomfort of standard material handling tasks through the comparison of multiple scanning devices including a commonly used wand scanner and two wearable solutions (smart glasses and a ring scanner). Ring scanner of most productive with smart glasses being both the least productive and comfortable.
查看更多>>摘要：Due to the intrinsic difficulties associated with simulating extreme events, it remains unclear how unpleasant emotional arousal might affect shooting performance among well-trained high-risk operators. To address this issue, an infantry rifle squad performed two simulated shooting exercises of different complexity (low vs. high) while exposed to unpleasant emotionally charged sound clips. A control group underwent the same experimental procedure without the presence of any sound clips. To externally validate our method of emotional arousal inoculation, we collected infantrymen's salivary cortisol and perceived arousal and valence levels over the experimental phases (i.e., baseline, shooting, and recovery). The dependent variables were their shooting performance (shot-to-hit ratio and instructor's evaluation) and the perceived degree of task complexity. Furthermore, we explored the variations of participants' nasal skin temperature during the shooting exercises. Salivary cortisol concentrations varied over time only for the squad exposed to emotionally charged stimuli. While emotional arousal had an effect on overall infantrymen performance (e.g., precision of movements while shooting), shooting accuracy was not affected. Emotional arousal did not influence nasal skin temperature. Overall, our results suggest that arousal inoculation based on emotionally charged sound clips could serve as a complementary (reliable and ethically appropriate) method to train high-risk operators to deal with emotional arousal. These findings may also contribute to a better understanding of the role of emotional arousal in operational effectiveness.
查看更多>>摘要：This study examined the effect of one-person and two-person team lifting on trunk muscle co-activation and activity and correlated them with the forces at lumbar spine at different risk levels. Eleven healthy subjects performed lifting tasks in the sagittal plane alone and together with another person matched by gender, anthmpometry, age, and strength at low, medium at high risk level according to the NIOSH equation. Our results showed that two-person team lifting reduces of the trunk muscles co-activation and activity compared to one-person lifting regardless of the level of risk. Moreover, in one-person lifting co-activation and muscle engagement increase with the forces on L5/S1 joint, while in two-person team lifting some correlations disappear, probably indicating that the muscular involvement in teams does not necessarily increase with risk level. Therefore, two-person team lifting could be recommended as one of the possible ergonomic interventions to reduce workers' biomechanical risk in industry activities in which manual lifting cannot be avoided.
NSTL
Elsevier