Movement and positioning of a virtual cuboid in 3d space in an augmented reality environment.

Human-virtual object interaction is common in both entertainment and work settings. This study investigated the movement time (MT) and subjective rating of difficulty (SRD) for moving a virtual cuboid in a 3D space. The participants wore an augmented reality (AR) headset, picked up a virtual cuboid, and placed it on an assigned target.

Relationship between one-handed push force and subjective rating of force exertion.

Background: Pushing is a typical workplace activity that may result in musculoskeletal disorders (MSDs). A convenient method of assessing the risk of MSDs is to determine the association between the force applied and the subjective rating of force exertion.

Objectives: This study aimed to determine the relationship between the subjective rating of force exertion and the force applied to both a fixed and a movable handle.

Factors Affecting Preventive Behaviors for Safety and Health at Work during the COVID-19 Pandemic among Thai Construction Workers.

Occupational health and safety risks are of major concerns in construction industry. The COVID-19 outbreak provides an additional risk that could drastically affect the safety risks and health of construction workers. Understanding the factors that affect the health and safety of construction workers is significant in reducing risky behaviors and enhancing worker preventive behaviors.

Mental workload assessments of aerial photography missions performed by novice unmanned aerial vehicle operators.

Background: Mental workload is one of the important variables in understanding human performance in drone operation.

Objective: To test the effects of gender, age group, flight route, and altitude on the flight performance and mental workload of the novice drone operators.

Methods: Ten male and ten female participants without prior drone operating experience joined.

Fatigue and Recovery of Muscles for Pulling Tasks.

Manual materials handling (MMH) contributes to musculoskeletal disorders (MSDs) in the workplace. The development and recovery of muscle fatigue are essential in work/rest arrangements for MMH tasks. A pulling experiment, including a muscle fatigue test and a muscle fatigue recovery test, was conducted.

Perceived difficulty, flight information access, and performance of male and female novice drone operators.

Background: Unmanned aerial vehicles (UAVs) or drones are becoming popular in both commerce and private usage. Behaviors of novice drone operators are critical to UAV flight safety.

Objectives: This study aims at discovering the perceived difficulty, flight information access frequency, and flight performance of novice drone operators.

Subjective and objective assessments of mental workload for UAV operations.

Background: Unmanned Aerial Vehicles (UAVs) have created safety problems for the publics. Assessments of the mental workload for UAV operations are essential to realize the causes of UAV accidents.

Objective: To test the following hypotheses: i.

Interventions to Improve Physical Capability of Older Adults with Mild Disabilities: A Case Study.

Ageing is related to changes in physical health, including loss of mobility and muscle function. It can lead to impaired physical capability and reduced quality of life. The purpose of this study was to investigate whether a physical activity rehabilitation program (PARP) could improve range of joint motion (ROM), grip strength, and gait speed of older adults with mild disabilities.

Modeling and Validation of Fatigue and Recovery of Muscles for Manual Demolition Tasks.

Manual demolition tasks are heavy, physically demanding tasks that could cause muscle fatigue accumulation and lead to work-related musculoskeletal disorders (WMSDs). Fatigue and recovery models of muscles are essential in understanding the accumulation and the reduction in muscle fatigue for forceful exertion tasks. This study aims to explore the onset of muscle fatigue under different work/rest arrangements during manual demolition tasks and the offset of fatigue over time after the tasks were performed.

Effects of handle height and load on the endurance time for simulated demolition tasks.

Background: Manual demolition tasks are heavy physical demanding tasks which involve forceful exertion of sustained pushing. They result in muscle fatigue which could lead to musculoskeletal disorders. Assessments of maximum endurance time (MET) are essential in understanding the developing of muscle fatigue for these tasks.

Risky scenario identification in a risk perception scale for construction workers in Thailand.

Introduction: Construction sites exhibit unique hazardous characteristics. Hence, investigating the causes of fatal and nonfatal accidents is extremely important to promote safety on construction sites. Literature shows a risk perception (RP) scale for construction workers; to expand the existing research, this study aims to identify risky scenarios for assessing the RP of Thai construction workers, with the goal of reducing workplace incidents.

Assessment of risk of tripping before and after crossing obstacles under dimmed lighting conditions.

Background: Tripping and falling are common at work. Investigating the perceived risk of tripping is important for the safety of workers.

Objective: To test the hypotheses that the perceived risk of tripping is affected by obstacle depth, obstacle height, number of obstacle, and light location under dimmed lighting conditions.

Slip and Fall Incidents at Work: A Visual Analytics Analysis of the Research Domain.

Slip and fall incidents at work remain an important class of injury and fatality causing mechanisms. An extensive body of safety research has accumulated on this topic. This article presents an analysis of this research domain.

Line-of-sight in operating a small unmanned aerial vehicle: How far can a quadcopter fly in line-of-sight?

A field study was conducted to investigate the probabilities of human participants to detect a small unmanned aerial vehicle (UAV) at a certain distance. A Phantom 4 quadcopter was remotely controlled to hover at one of the 32 pre-determined locations in the air. Thirty-two participants on the ground were requested to judge if they could see the quadcopter on a four-point scale: 1.

Strength Decrease, Perceived Physical Exertion and Endurance Time for Backpacking Tasks.

Manual material handling (MMH) tasks create a burden for workers which could result in musculoskeletal injuries. Assessments of the decrease of muscular strength and the maximum endurance time (MET) for MMH tasks are essential in studying the ergonomic risk of MMH tasks. A backpacking experiment was conducted for measuring the MET for MMH tasks.

Correction: Pulling strength, muscular fatigue, and prediction of maximum endurance time for simulated pulling tasks.

[This corrects the article DOI: 10.1371/journal.pone.

Pulling strength, muscular fatigue, and prediction of maximum endurance time for simulated pulling tasks.

Truck pulling is one of the common manual materials handling tasks which contribute to musculoskeletal disorders. The maximum endurance time (MET) for two-handed truck pulling tasks has been rarely discussed in the literature. The objectives of this study were to explore the development of muscular fatigue when performing two-handed pulling task and to establish models to predict the MET.

Modeling of maximum endurance time for static pulling tasks.

Background: Pallet truck pulling is one of the common manual materials handling tasks which could result in musculoskeletal injuries. The endurance time for sustained truck pulling tasks has been rarely discussed in the literature.

Objective: The objectives of this study were to measure the muscular fatigue after performing a pulling task and to establish models to predict the maximum endurance time for truck pulling tasks.

Subjective assessments of floor slipperiness before and after walk under two lighting conditions.

A gait experiment was performed. The participants were tested under shoes, floors, surface and lighting conditions. They gave floor slipperiness ratings before and after a gait trial.

Modeling of predictive muscular strength for sustained one-handed carrying task.

Background: Manual materials handling (MMH) tasks are common. They are considered major contributors of musculoskeletal injuries and are the sources of financial burden for industries in terms of lost work days and worker compensation costs. One-handed carrying is common and could result in arm fatigue.

Isometric arm strength and subjective rating of upper limb fatigue in two-handed carrying tasks.

Sustained carrying could result in muscular fatigue of the upper limb. Ten male and ten female subjects were recruited for measurements of isometric arm strength before and during carrying a load for a period of 4 minutes. Two levels of load of carrying were tested for each of the male and female subjects.

Friction between footwear and floor covered with solid particles under dry and wet conditions.

Solid particles on the floor, both dry and wet, are common but their effects on the friction on the floor were seldom discussed in the literature. In this study, friction measurements were conducted to test the effects of particle size of solid contaminants on the friction coefficient on the floor under footwear, floor, and surface conditions. The results supported the hypothesis that particle size of solids affected the friction coefficient and the effects depended on footwear, floor, and surface conditions.

Perceived floor slipperiness and floor roughness in a gait experiment.

Background: Slips and falls contribute to occupational injuries and fatalities globally. Both floor slipperiness and floor roughness affect the occurrence of slipping and falling. Investigations on fall-related phenomena are important for the safety and health of workers.

Shoe sole tread designs and outcomes of slipping and falling on slippery floor surfaces.

A gait experiment was conducted under two shoe sole and three floor conditions. The shoe soles and floors were characterized by the tread and groove designs on the surface. The coefficients of friction (COF) on the floor in the target area were measured.

A field assessment of floor slipperiness in a student cafeteria.

Investigation of floor slipperiness is critical in studying the risk of slips and falls. This research conducted friction measurements and employee survey on floor slipperiness in a student cafeteria in a university in China in order to study the correlation between the two types of floor slipperiness measure. It was found that the fryer area in kitchen 1 and the meat defrost sink in kitchen 2 had significantly the lowest coefficient of friction (COF) values among all areas in the same kitchen.