• Journal of the Ergonomics Society of Korea
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• v.13 no.2
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• pp.13-24
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• 1994

The objectives of this study are twofold : (1) to investigate musculoskeletal discomfort for sedentary workers in offices ane (2) to revise the Korean Standard for the design of office chairs in order to reduce or eliminate the physical discomfort or the office workers. Two hundred seventy-one office workers from nineteen different companies companies were selected to evaluate the musculoskeletal discomfort and indibidual features of chair design. A statistical analysis of the survey rebealed that the office currently being used had two major deficiencies such as insufficient adjustability and inappropriate design specifications in ergonomic sense. A stepwise regression analysis showed that the deficiencies on the musculoskeletal discomfort of the workers. Based on the ergonomic design pronciples, was debeloped to revise the Korean Standard for the design specifications of office chairs. An application of the methodology was made amend the design specifications of the four factors such as seat pan height, seat pan width, and seat pan inclunation. Their effects were evident in the musculoskeletal discomfort of the workers.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.1
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• pp.100-110
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• 1999

The objectives of this study are twofold: (1) to evaluate the cockpit of three Korean air force fighters such as F-4, F-5, and F-16 in an ergonomic perspective and (2) to measure the musculoskeletal discomfort of the fighter pilots. For the study, 369 air force pilots from 7 squadrons were surveyed. The study shows that the cockpit design of F-16 is superior to the others. However, F-4 is the worst among them. Statistical analyses reveal that the seat in the cockpit raised the most complaints, regardless of types of fighter planes. The main problems with the seat included inappropriate designs of the backrest angle, seat cushioning, and parachute harness. Also frequently cited are various control switches, control stick, rudder pedal, and the throttle. That these items lack human integration is found in remote positions and improper dimensions. The implications of these findings are discussed. The self-reported musculoskeletal complaints show that the main discomfort is on the back and neck. Also, the buttocks, shoulders, and the legs/knees are common sites of discomfort. A stepwise regression analysis shows that the back discomfort, is mainly caused by the use of the seat, rudder pedal, control stick, and switches. A Spearman rank correlation coefficient test also reveals that job dissatisfaction of the pilots is related to the complaints with the cockpit and musculoskeletal discomfort. These findings suggest that more comprehensive studies for cockpit design in the aspects of functional anthropometry of Korean pilots are needed to reduce the musculoskeletal discomfort.

• The Journal of the Korea Contents Association
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• v.9 no.9
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• pp.249-258
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• 2009

The purpose of this study is to identify the factors influencing the musculoskeletal discomfort and the physical region related symptoms. The outcome of the study uses KOSHA Code H-30-2003 which defines possible symptoms into different categories. Symptom I, ll showing the highest occurrence rate in shoulder and neck regions and most of Symptom III, IV come from back region. Analysis of the factors influencing the musculoskeletal discomfort vary in different parts of the body. In the neck region, the discomfort related to rest and the computer keyboard. Gender affects the magnitude of pain in the shoulder region. Wrist pain is related to the chairs being used and back discomfort is influenced by shoulder exercise and the degree of rest taken. Physical fatigue due to work affects all the regions mentioned above. Conclusively, office workers are prone to the musculoskeletal discomfort due to their work environment. To alleviate this problem, the workers need to be educated with proper long-term musculoskeletal related health programs and exercise program containing various stretching methods. In addition, the effort to improve the variables in this study would help to reduce the rate of musculoskeletal discomfort.

• Proceedings of the ESK Conference
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• 1995.10a
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• pp.109-113
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• 1995

This study was designed to investigate the effects of work postures and anthropometry on the musculoskeletal discomfort of the telephone operators involved in VDT tasks. The level of musculoskeletal discomfort were evaluated for 279 VDT operators from three different workplaces. The work postures and the anthropometric data were evaluated for 70 VDT operators out of the total of 279 operators. Multiple regression analysis was utilized to examine the relation- ship between the measured ergonomic variables and the level of the musculoskeletal discomfort. It is evident from the result of the study that the ergonomic factors have great influences on the level of the musculoskeletal discomfort.

• Journal of agricultural medicine and community health
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• v.16 no.1
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• pp.40-47
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• 1991

Musculoskeletal disorders are a major cause of occupational disabilities. Approximately thirty percent state that the major reason for an inability to work is a musculoskeletal problem. A farm work is associated with increased stress and trauma to joints. Chronic overuse injuries are a result of stresses that exceed the body's adaptive or healing capabilities. They can occur in bone, tendons and muscle-tendon-bone junctions. The aim of the investigation was to the study the frequency of pain, ache, and discomfort in the musculoskeletal system among farmers, to find possible correlations between these symptoms and various working positions and different working actions. A questionnaire was answered by 138 farmers. Of those who answered the questionnaire 82% had pain and discomfort from back, shoulders, arms in orders, The result showed that musculoskeletal pain predominate in the farming seasons, and of those who had pain and discomfort 89% thought that farm works had a correlation with the pain and discomfort of musculoskeletal system. But only 17% of quationnaire were put to periodic medical examinations, and 50% of those who had pain and discomfort consulted a doctor. Education in effective pain treatment should therefore be intensifide to ascertain that farmers in rural areas have satisfactory knowledge of the musculoskeletal pain as a chronic overuse syndrome.

• Korean Journal of Computational Design and Engineering
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• v.17 no.1
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• pp.62-70
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• 2012

This paper proposes a novel discomfort assessment method for truck ingress and egress motions based on the maximum-voluntary-contraction (MVC) ratios of muscles obtained by biomechanical analysis of human musculoskeletal models. In this study, a human motion to enter and exit a truck cabin with different types and heights of footsteps is first measured using an optical motion capture system and load sensors. Next, in a biomechanical analysis system, a human musculoskeletal model with contacting conditions on footsteps and handles is modeled, and then joint torques and muscles forces are calculated by inverse dynamics of the musculoskeletal model with the motion data. Finally, the MVC ratios for the muscles are calculated and their statistical values are used as the measure of discomfort. To ensure the feasibility of our method, subjective discomfort levels have been investigated through the participants' experiments and questionnaires and compared to the results of our method. Comparing to the existing methods based on joint angles or torques, our approach provide a more essential criterion for discomfort because it is based on the muscle contraction by which an active human motion is basically generated.

• Journal of the Korean Society of Safety
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• v.16 no.1
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• pp.73-78
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• 2001

It has been proposed that the acceptable level of discomfort was a valid measure of postural loading. Although the number of women employees has increased at a much faster rate than men workers did and female workers are thought to be more vulnerable to musculoskeletal disorders, most previous studies dealt with perceived discomforts for joint motions focused on male subjects. This study aims to measure perceived discomfort ratings of females for static joint motions. Ten female subjects participated in the experiment measuring perceived discomforts, in which almost every possible joint motion was included and the free modulus method of the magnitude estimation was employed. The results showed that discomfort levels were dependent on the joint motions and joints, and subjective discomfort ratings of women were significantly larger than those of men.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.1
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• pp.264-273
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• 2012

This cross-sectional study was investigated musculoskeletal discomfort symptoms and related factors on some middle high school teachers. Self-questionnaire of KOSHA CODE H-30-2003 was done with 250 teachers from 1st to 15th October, 2010, the data from 231 teachers (68 male, 163 female) was statistically analyzed to search the factors related to musculoskeletal discomfort symptoms. According to NIOSH rate of musculoskeletal discomfort symptoms by body parts was 36.8%. Musculoskeletal discomfort symptoms related to age, school types, subjective health status, housekeeping time, VDT work time and regular rest. After adjusting for related variables, odds ratio (OR) of musculoskeletal discomfort symptoms was correlation significantly to subjective health status unhealthy (OR 11.75, 95% Confidence Interval, CI, 3.56-378.78). In addition, ORs (95% CI) of age (40-49) and housekeeping time (${\geq}3$) were 4.63 (1.82-26.18) and 4.33 (1.97-19.34). Analysis of the factors influencing the musculoskeletal discomfort symptoms vary in different parts of the body. The most discomfort symptoms by parts was neck (26.0%) and shoulder (30.0%). In the neck region was related to subjective health status and regular rest. In the shoulder and waist region was subjective health status and sex. Age was wrist/finger, leg/foot was related to subjective health status, sex and VDT work time. Age, school types, subjective health status, housekeeping time, VDT work time and regular rest related to musculoskeletal discomfort symptoms and the most discomfort symptoms by parts was neck and shoulder.

• Journal of radiological science and technology
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• v.45 no.4
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• pp.355-363
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• 2022

This study was to investigate the prevalence rate of musculoskeletal disorders in relation to general characteristic factors, living environment factors, and work environment factors for sonographer's. For the response questions, the guidelines for musculoskeletal burden work were used. For statistical analysis, SPSS 26.0 version was used. For the common body parts of the sonographer's who responded, the prevalence was investigated by dividing the group into a group with high pain or discomfort and a group with low pain or discomfort according to the degree to which they experienced symptoms during the past 12 months. Multiple logistic regression analysis was used to determine the variance inflation factor(VIF), odds ratio (OR) and corresponding 95% confidence interval (CI). A p-value of <0.05 was considered statistically significant. As a result, housework hours, examination history, regular physical activity, number of patient examinations per day, and sitting posture were investigated as variables for rate musculoskeletal disorders. The sonographer's occupational group was found to have a high prevalence rate of musculoskeletal disorders like various other occupational groups. Based on the results of this study, it is judged that musculoskeletal disorders can be reduced by recognizing musculoskeletal disorders and improving work environment factors.

• Journal of the Korean Society of Safety
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• v.14 no.2
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• pp.148-154
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• 1999

A self-report musculoskeletal assessment tool was adapted following field use by ergonomic analysis teams and was administrated to 100 employees of ChangWon techno-complex. Results were analyzed to determine of the self-report could adequately predict whether or not an employee reportedly sought medical treatment for a work-related discomfort. It is anticipated this tool can be utilized as an easily administrated, proactive surveillance instrument to assist in early identification of ergonomic concerns and to help prioritize jobs for intervention.