Effects of different tools and working height on physical workload in vertical cleaning tasks applying ambient control techniques.

This study aimed to investigate the effects of different tools and working heights on physical workloads in vertical cleaning tasks. Thirty healthy adults were recruited to use a rag and a long-handle tool (LHT) to simulate cleaning operations on the Wii Fit board surfaces of 3 different heights, respectively. Participants used a lower 50th percentile force but were required to spend a longer time to finish the task while using an LHT than using a rag. The tool preferences were the main factors considered for efficiency and personal subjective workload and physiological load. 76.6% of the participants preferred to use the LHT instead of the rag at a high task height, but 70% preferred to use the rag when working at a medium task height. For low workload cleaning tasks on vertical surfaces, employers should provide cleaners with different handle lengths tools to choose from to reduce the cleaner's workload.

Disclosing Critical Voice Features for Discriminating between Depression and Insomnia-A Preliminary Study for Developing a Quantitative Method.

Background: Depression and insomnia are highly related-insomnia is a common symptom among depression patients, and insomnia can result in depression. Although depression patients and insomnia patients should be treated with different approaches, the lack of practical biological markers makes it difficult to discriminate between depression and insomnia effectively. Purpose: This study aimed to disclose critical vocal features for discriminating between depression and insomnia. Methods: Four groups of patients, comprising six severe-depression patients, four moderate-depression patients, ten insomnia patients, and four patients with chronic pain disorder (CPD) participated in this preliminary study, which aimed to record their speaking voices. An open-source software, openSMILE, was applied to extract 384 voice features. Analysis of variance was used to analyze the effects of the four patient statuses on these voice features. Results: statistical analyses showed significant relationships between patient status and voice features. Patients with severe depression, moderate depression, insomnia, and CPD reacted differently to certain voice features. Critical voice features were reported based on these statistical relationships. Conclusions: This preliminary study shows the potential in developing discriminating models of depression and insomnia using voice features. Future studies should recruit an adequate number of patients to confirm these voice features and increase the number of data for developing a quantitative method.

Body volume estimation equation for male laborers in Taiwan.

The purpose of this study was to develop a body volume (BV) estimation equation for male laborers in Taiwan with body weight (W) and stature height (H) as initial estimators. A three-dimensional (3D) body scanner and a 3D foot scanner were used to measure the 3D range data of 100 male laborers in this study. Subjects' BV was extracted from the 3D body model, and H and W were used as independent variables in regression analysis. The results show that the final BV estimation equation is BV = 1122.927 × W0.972, with R2 = 0.949. Thirty extra male subjects were scanned to compare this BV estimation equation with those in previous studies. The results show that this BV estimation equation had the smallest absolute mean difference at 1.1458 L and the smallest standard error of the estimate at 2.48% in comparison.

Predicting Emotional Valence of People Living with the Human Immunodeficiency Virus Using Daily Voice Clips: A Preliminary Study.

To detect depression in people living with the human immunodeficiency virus (PLHIV), this preliminary study developed an artificial intelligence (AI) model aimed at discriminating the emotional valence of PLHIV. Sixteen PLHIV recruited from the Taoyuan General Hospital, Ministry of Health and Welfare, participated in this study from 2019 to 2020. A self-developed mobile application (app) was installed on sixteen participants' mobile phones and recorded their daily voice clips and emotional valence values. After data preprocessing of the collected voice clips was conducted, an open-source software, openSMILE, was applied to extract 384 voice features. These features were then tested with statistical methods to screen critical modeling features. Several decision-tree models were built based on various data combinations to test the effectiveness of feature selection methods. The developed model performed very well for individuals who reported an adequate amount of data with widely distributed valence values. The effectiveness of feature selection methods, limitations of collected data, and future research were discussed.

Evaluation of a proposed chair with an arm support for wiring terminal blocks on a vertical plane.

To reduce the muscular exertion of an operator wiring terminal blocks on a vertical plane, a chair with a unique back that can be used as a back support or arm support is proposed in this study. A digital version of the chair was first developed based on anthropometric data and tested with a digital anthropometric subject using the Jack software before the physical chair was developed. To evaluate the effects of the physical chair, an experiment of wiring terminal blocks was conducted with 12 subjects to test whether the use of the arm support can reduce muscular exertion. The results showed that (1) exertion on the anterior deltoid, upper trapezium, and erector spinae muscles decreased with decrease in terminal block height; (2) using the arm support reduced exertion on the anterior deltoid and upper trapezium muscles; and (3) the subjects reported less self-perceived fatigue in the wrist, elbow, and shoulder regions when the arm support was used. These results confirm that the proposed chair can reduce muscular workload in the shoulder muscle over a proper range of working heights. However, using the arm support may restrict certain working postures and lead to force generation in upper extremity muscles.

Design and feasibility study of an integrated pointing device apparatus for individuals with spinal cord injury.

Despite the commercial availability of numerous computer-pointing devices, many severely disabled individuals still rely on customized equipment to operate computers. This study presents a novel Integrated Pointing Device Apparatus (IPDA) that integrates numerous commercial pointing devices. The novel IPDA, which complies with a standard USB 1.1 interface, is compatible with most tested computer-pointing devices and flexibly integrates commercial computer devices, tailoring them to suit individual needs. By using simple integrated circuit design and low-cost electronic components, this low-cost apparatus is easily maintained. The feasibility of the IPDA was evaluated by four subjects with high-level cervical (C4-5) spinal cord injury (SCI). Participants performed normal move-and-click and drag-and-drop tasks typically performed by computer pointing devices. Each participant not able to use a traditional computer mouse or trackball were able to operate a computer adequately with the IPDA and three including one operating a trackball with his chin, operated computers easily and smoothly. This feasibility study showed that the IPDA effectively integrates commercial pointing devices, thereby providing the possibility for some people with SCI to obtain computer operability. This study demonstrated the advantages of flexibility, low cost, and acceptable efficiency of the novel IPDA.

Differences in computer exposure between university administrators and CAD draftsmen.

This study utilized an external logger system for onsite measurements of computer activities of two professional groups-twelve university administrators and twelve computer-aided design (CAD) draftsmen. Computer use of each participant was recorded for 10 consecutive days-an average of 7.9+/-1.8 workdays and 7.8+/-1.5 workdays for administrators and draftsmen, respectively. Quantitative parameters computed using recorded data were daily dynamic duration (DD) and static duration, daily keystrokes, mouse clicks, wheel scrolling counts, mouse movement and dragged distance, average typing and clicking rates, and average time holding down keys and mouse buttons. Significant group differences existed in the number of daily keystrokes (p<0.0005) and mouse clicks (p<0.0005), mouse distance moved (p<0.0005), typing rate (p<0.0001), daily mouse DD (p<0.0001), and keyboard DD (p<0.005). Both groups had significantly longer mouse DD than keyboard DD (p<0.0001). Statistical analysis indicates that the duration of computer use for different computer tasks cannot be represented by a single formula with same set of quantitative parameters as those associated with mouse and keyboard activities. Results of this study demonstrate that computer exposure during different tasks cannot be estimated solely by computer use duration. Quantification of onsite computer activities is necessary when determining computer-associated risk of musculoskeletal disorders. Other significant findings are discussed.

Ergonomic risk factors for the wrists of hairdressers.

This study utilized a portable data logger to measure the wrist angles and forearm flexor and extensor electromyography (EMG) of 21 hairstylists. The hairstylists were divided into two groups, one with 11 barbers (9 males and 2 females) specializing in men's hairdressing, and one with 10 hairdressers (2 males and 8 females) specializing in women's hairdressing. The standard haircut task was divided into three subtasks: hair cutting, washing and blow-drying. The mechanical exposures of the overall task and subtasks were quantified to compare how subtasks, occupational groups, and gender groups differ. Experimental results show that the average time to finish a woman's haircut (51.4min) is significantly longer than that for a man's haircut (35.6min) (p<0.005). Female hairstylists had significantly greater EMG activity than male hairstylists did (p<0.001). The non-dominant hands of hairdressers have significantly higher overall wrist velocity than those of barbers (p<0.005). Analytical results suggest that the relatively higher force exertion and wrist velocity of female hairstylists combined with prolonged exposure may account for the higher rate of hand/wrist pain in female hairdressers than in male barbers.