Publications by authors named "Jia-Hua Lin"

The purpose of this study was to identify if workplace interventions, (i.e., mindfulness classes and monetary incentives for gym attendance), influenced workers' physical activity.

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Previous studies on Human Factors and Ergonomics (HFE) have primarily examined the impact of Work-From-Home (WFH) on worker health and well-being, yet little research has examined the optimal implementation process of WFH programs. Work systems perspective suggests that organizational policies, leadership, and psychological factors collectively influence the success of organizational change efforts. Our study explored the roles of managerial/supervisory, psychological, and organizational policy factors in facilitating the relationship between employees' HFE awareness and their acceptance and satisfaction with the WFH arrangement.

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There is no report on the relationship between congenital malformation of the outer ear and hearing, which makes it possible to predict the hearing level just based on microtia grades. To investigate the correlation between two types of congenital malformation of the outer ear [microtia and Outer Ear Canal Malformation (OECM)] and hearing, as well as the interrelationship among all three variables. A total of 535 cases (598 ears) of congenital malformation of the middle and outer ear (CMMOE) with hearing data, out of which 319 cases (349 ears) microtia with available images and graded by I-V, 449 cases (482 ears) OECM graded by atresia, stenosis and normal, and 87 cases (87 ears) OEC atresia graded I-IV, 301 cases (301 ears) with materials of microtia, OECM and hearing at the same time were carried out correlation analysis.

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Background: In pure tone audiometry, when the difference of the Average Air Conduction Threshold of pure tone (AACT) between bilateral ears is more than 40 dB HL masking must be performed on the poor side, However, we found that masking also make significance difference when the binaural AACT difference (AACT-d)was less than 40 dB HL in some patients.

Aims/objective: Assessing the significance of masking for the poor ear in pure tone audiometry in patients with different types of deafness to obtain preoperative accurate hearing.

Material And Methods: A comparative analysis of 163 cases (163 ears) with hearing difference between two ears was conducted, who were divided into three groups: G1 Congenital Malformation of the Middle and Outer Ear (CMMOE)as conductive deafness, 63 ears, G2 sudden deafness as sensorineural deafness, 65 ears, and G3 media otitis as conductive or mixed deafness,35 ears.

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Background: It is the challenging clinical issue of combining debridement of infected lesions and retaining the blood skin flap for auricle reconstruction in patients of Congenital Malformation of the Middle and Outer Ear with Infection (CMMOEI).

Aims/objectives: To innovate and introduce an surgery incision to solve the challenging clinical issue of a combined debridement of infection yet retaining a well vascularized skin flap for auricle reconstruction in patients with CMMOEI.

Material And Methods: A combined innovated incision of ear sulcus and prefabricated earlobe was used for 23 cases (23 ears) with CMMOEI, The success in the management of the encountered infections, and the short and moderate-term outcome of the innovated incision to preserve a well-vascularized skin flap for subsequent auricle reconstruction were reviewed.

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Background: There is no report about the definition, classification and clinical epidemiological study of congenital ear malformation (CEM). To investigate the definition, clinical classification and distribution of a large number of CEM cases, along with the clinical and epidemiological characteristics associated with congenital malformation of the middle and outer ear (CMMOE).

Material And Methods: A total of 3231 cases (4714 ears) with CEM and related malformations were retrospectively analyzed, including 2,658 cases (4,064 ears) CEM and 573 cases (650 ears) preauricular fistulas and accessory ears, specifically related malformations to CEM.

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The incidence of re-stenosis or re-atresia after reconstruction of the Outer Ear Canal (OEC) in patients with Congenital Malformation of the Middle and Outer Ear (CMMOE) is very high (up to 48%), and it has been a difficult problem for otologists not being able to solve. To explore new strategies and methods to improve re-stenosis or re-atresia after reconstruction of the OEC in patients with CMMOE. According to the characteristics of reconstructed OEC (r-OEC) re-stenosis or re-atresia summarized by us, a number of new prevention strategies and methods have been proposed and related patent products have been designed, including the improvement of covering epithelium types and skin grafting methods (7 types), simulated drum ring function to prevent the formation of negative pressure in the cavity, and strengthen postoperative support to reduce skin shrinkage and bone hyperplasia.

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Introduction: This study aimed to investigate whether work pace is a critical indicator for predicting a janitor's risk of work-related musculoskeletal disorders (WMSDs).

Method: Field measurements were obtained from commercial building janitors as well as the determination of work pace. Physiological responses collected were heart rate, energy expenditure (calories), activity level (METs), steps, trunk posture.

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Observer, manual single-frame video, and automated computer vision measures of the Hand Activity Level (HAL) were compared. HAL can be measured three ways: (1) observer rating (HAL), (2) calculated from single-frame multimedia video task analysis for measuring frequency (F) and duty cycle (D) (HAL), or (3) from automated computer vision (HAL). This study analysed videos collected from three prospective cohort studies to ascertain HAL, HAL, and HAL for 419 industrial videos.

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After the onset of the COVID-19 pandemic, many office workers transitioned to working-from-home (WFH) which altered routine physical activity (PA). To understand how these workers' PA were affected throughout the pandemic, PA data collected in January, April, June, and December 2020 with an activity tracker and a validated survey were analyzed. Between January and December, it was found that step counts during the weekday decreased (p < 0.

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Workers performing cleaning duties experience higher injury rates, especially in the form of musculoskeletal disorders (MSDs), than other industries. It is essential to understand the inherent risks associated with the nature of this occupation. Based on the Balance Theory (Smith & Carayon-Sainfort, 1989), this review surveys the current literature, especially those published since the previous review paper (Kumar & Kumar, 2008), and identifies which elements contributing to MSD risks were examined: task, technology, organization, environment, individual, and their interactions.

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Janitors' jobs require repetitive work with low control (skill discretion, decision authority) and social support. Previous studies have found this constellation of work conditions leads to high stress levels. This study investigated the relationships among job demand-control-support, burnout, and musculoskeletal symptoms for commercial janitors in Washington State.

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To evaluate the postures in ergonomics applications, studies have proposed the use of low-cost, marker-less, and portable depth camera-based motion tracking systems (DCMTSs) as a potential alternative to conventional marker-based motion tracking systems (MMTSs). However, a simple but systematic method for examining the estimation errors of various DCMTSs is lacking. This paper proposes a benchmarking method for assessing the estimation accuracy of depth cameras for full-body landmark location estimation.

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Musculoskeletal risk is mediated by body posture, especially for static tasks. Workstations that require non-neutral postures can lead to increased load, muscular fatigue and injury risk. However, demands during simple axial rotation tasks are not well-defined.

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Material-cart handling can be strenuous and lead to overexertion injuries. The aim of this study is to produce a thorough understanding of how the cart condition, tire type, physical environment-related factors, and load interact to influence the ergonomics and productivity of cart handling. Eighteen roofing carts with different conditions, tires, and loads were tested by one subject on three laboratory tracks: one L-shaped, one with ramps within constrained spaces, and one with obstacles within constrained spaces.

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Urolithiasis is one of the most common urologic diseases in industrialized societies. More than 80% of renal stones are composed of calcium oxalate, and small changes in urinary oxalate concentrations affect the risk of stone formation. Elucidation of the source of oxalate and its mechanism of transport is crucial for understanding the etiology of urolithiasis.

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Objectives: Varied work-related musculoskeletal disorders (WMSDs) claim rates were found between companies even when they were in the same sectors with similar sizes. This study aimed to (i) identify common risk factors for back, shoulder, hand/wrist, and knee WMSDs among manufacturing jobs, and (ii) characterize the biomechanical exposures in jobs and work organizational practices between high and low WMSD claim rate companies so that more focused, industry-specific intervention strategies may be developed.

Methods: Using historical workers' compensation data, manufacturing companies were divided into two paired groups (low and high in the lower 25%ile and higher 75%ile, respectively).

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Background: Sit-stand workstations have been introduced in the workplaces to address the adverse sedentary effect inherent to typical office jobs. Existing field or laboratory studies showed that standing interventions are not a detriment to work productivity or performance. The effect of gradient standing proportion on these measures is still unknown.

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Cranking the landing gear is a common task performed by truck drivers to raise or lower trailers. This task poses a risk to the shoulder joint due to the required forceful exertion and the posture constrained to the hand-handle interface. As a potential occupational risk, there has been no definitive guideline for best practices among truck drivers.

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Objective: A method for automatically classifying lifting postures from simple features in video recordings was developed and tested. We explored if an "elastic" rectangular bounding box, drawn tightly around the subject, can be used for classifying standing, stooping, and squatting at the lift origin and destination.

Background: Current marker-less video tracking methods depend on a priori skeletal human models, which are prone to error from poor illumination, obstructions, and difficulty placing cameras in the field.

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Twelve office workers participated in a study investigating effects of four sit/stand schedules (90-min sit/30-min stand, 80/40, 105/15, and 60/60) via several objective and subjective measures (muscle fatigue, foot swelling, spinal shrinkage, and self-reported discomfort). Results showed that there were no significant differences in shoulder and low back static muscle activities between sitting and standing. Muscle fatigue was developed during workday under all schedules.

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Shoulder joint kinematics has been used as a representative indicator to investigate musculoskeletal symptoms among computer users for office ergonomics studies. The traditional measurement of shoulder kinematics normally requires a laboratory-based motion tracking system which limits the field studies. In the current study, a portable, low cost, and marker-less Microsoft Kinect™ sensor was examined for its feasibility on shoulder kinematics measurement during computer tasks.

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Optimization combined with a musculoskeletal shoulder model has been used to estimate mechanical loading of musculoskeletal elements around the shoulder. Traditionally, the objective function is to minimize the summation of the total activities of the muscles with forces, moments, and stability constraints. Such an objective function, however, tends to neglect the antagonist muscle co-contraction.

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