• Journal of the Korean Society of Industry Convergence
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• v.24 no.3
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• pp.271-281
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• 2021

Pinus densiflora and Larix kaempferi forests not only extended the plantation management area but also cultivated to the sustainable wood supply chain during the last 5-years. These prescriptions are primarily done by manual operation activities, particularly in young tree tending. Two types of tending activities, brashing by brush cutter(BB) and pruning by pruning shear and saw(PP), were selected for the investigate of musculoskeletal disorders' level and postural risks using Ovako Working Posture Analysis System (OWAS). The postural risk indexes (BB and PP) ranged from 115 to 125 and 102 to 105, respectively. There is no significant difference between the species. The young tree tending operations had low postural risks. The results may be used as basic data to develop technical guideline for safe young trees.

• Journal of Oral Medicine and Pain
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• v.48 no.3
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• pp.75-80
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• 2023

Temporomandibular disorders (TMDs) are a group of musculoskeletal disorders that encompass symptoms caused by abnormalities of the craniofacial structures of the temporomandibular joint (TMJ), muscles involved in the masticatory system, and other related tissues or structures. Although TMDs can occur at any age, research on the prevalence, epidemiology, and treatment strategies of TMDs has been conducted in all age groups, but primarily in adults. Unlike adults, children and adolescents are in a period of cognitive and physical development. Because of this growth potential, children respond better to TMD treatment than adults do. However, clinicians must remember that chronic pain and growth abnormalities can occur if the patient's symptoms and signs are not accurately diagnosed and treated. This article reviews the growth and development of the craniofacial region, including the TMJ, and discusses considerations when diagnosing and treating TMDs in children and adolescents.

• Journal of Korean Institute of Industrial Engineers
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• v.42 no.2
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• pp.122-128
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• 2016

The purpose of this study is to improve the firing elevation driving method for towed howitzer to prevent the musculoskeletal disorders. To adjust the firing elevation, it is required to rotate the hand wheel and this work has been done manually in the firing test range as the same method as field artillery troops. In the firing test range, the motor-driven firing elevation adjustment device was developed to improve the working efficiency and safety. These were compared by using posture classification scheme of RULA and REBA. It was measured elapsed time to investigate the improved operational efficiency. The optimal posture of upper body to operate the hand wheel for field artillery troops was proposed.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.2
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• pp.72-92
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• 2000

This research has conducted studies on an Oriental medicine-based method of diagnosing of occupational musculoskeletal system diseases. This researcher has searched through existing relevant medical literature. Also, this researcher has worked on a moire topography using moire topography. In this course, this researcher has reached the following conclusion in relation to the possibility of using a moire topography as a diagnosing device of musculoskeletal system diseases under Oriental medicine . 1 The Western medicine outlines its criteria of screening occupational musculoskeletal system diseases as follows A. The occupational musculoskeletal diseases must clearly include one or more of the subjective symptoms characterized by pain, hypoesthesia dysaesthesia, anaesthesia. etc . B, There should be clinically admitted objective observations and diagnosis outlining that the disease concerned shows symptoms such as tenderness, induration. and edema that can appear with occupational musculoskeletal system diseases. dyscinesia should be admitted with the disease concerned, or there should be observations and diagnosis outlining that abnormality exists in electric muscular or nervous diagnosis and examination . C. It should be admitted that prior to the occurrence of symptoms or observations and diagnosis on musculoskeletal system-related diseases, a patient has been engaged in works with conditions requiring improper work posture or work movement. That is, this is an approach whereby they see abnormality in the musculoskeletal system come from material and structural defect, and adjust and control abnormality in the musculoskeletal system and secreta . 2. The Oriental medicines sees that a patient develops the pain of occupational musculoskeletal diseases as he cannot properly activate the flow of his life force and blood thus not only causing formation of lumps in the body and blocking the flow of life force and blood in some parts of the body. Hence, The Oriental medicine focuses on resolving the cause of weakening the flow of life force and blood, instead of taking material approach of correcting structural abnormality Furthermore , Oriental medicine sees that when muscle tension builds up, this presses blood vessels and nerves passing by, triggering circulation dyscrasia and neurological reaction and thus leading to lesion. Thus, instead of taking skeletal or neurophysiological approach. it seeks to fundamentally resolve the cause of the flow of the life force and blood in muscles not being activated. As a result Oriental medicine attributes the main cause of musculoskeletal system diseases to muscle tension and its build-up that stem from an individual's long formed chronicle habit and work environment. This approach considers not only the social structure aspect including companies owners and work environment that the existing methods have looked at, but also individual workers' responsibility and their environmental factors. Hence, this is a step forward method. 3 The diagnosis of musculoskeletal diseases under Oriental medicine is characterized by the fact that an Oriental medicine doctor uses not only photos taken by himself, but also various detection devices to gather information and pass comprehensive judgment on it. Thus, it is the core of diagnosis under Oriental medicine to develop diagnosing devices matching the characteristics of information to be induced and to interpret information so induced from the views of Oriental medicine. Diagnosis using diagnosing devices values the whole state of a patient and formal abnormality alike, and the whole balance and muscular state of a patient serves as the basis of diagnosis. Hence, this method, instead of depending on the information gathered from devices under Western medicine, requires devices that provide information on the whole state of a patient in addition to the local abnormality information that X-ray. CT, etc., can offer. This method sees muscle as the central part of the abnormality in the musculoskeletal system and thus requires diagnosing devices enabling the muscular state. 4. The diagnosing device using moire topography under Oriental medicine has advantages below and can be used for diagnosing musculoskeletal system diseases with industrial workers . First, the device can Provide information on the body in an unbalanced state. and thus identify the imbalance and difference of height in the left and right stature that a patient can not notice at normal times. Second, the device shows the twisting of muscles or induration regions in a contour map. This is not possible with existing shooting machines such as X-ray, CT, etc., thus differentiating itself from existing machines. Third, this device makes it possible for Oriental medicine to take its unique approach to the abnormality in the musculoskeletal system. Oriental medicine sees the state and imbalance state in muscles as major factors in determining the lesion of musculoskeletal system, and the device makes it possible to shoot the state of muscles in detail. In this respect, the device is significant. Fourth, the device has an advantage as non-aggression diagnosing device.

• Journal of Korean Physical Therapy Science
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• v.9 no.3
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• pp.97-106
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• 2002

Purpose. This study was tried to compare the effect of the change in postural deviation caused by the pain side Subjects and Methods. Inpatients and outpatients (n=71) were selected from I hospital who have a musculoskeletal low back pain and shoulder pain without any history of the central nervous system (CNS) lesions, orthopaedic problems of the both lower extremities, or the vestibular and the visual default. For the control group, normal and healthy subjects (n=30) were selected without any history of weight bearing disorders. the weight bearing was rated by the computerized force plate. Results. 1) Postural deviation was not significant difference between patients and control group(p<0.01). But postural deviation in patients was more pronounced than control group. 2) There was significant difference of postural deviation between in patients according to the pain side(p<0.01). When the pain side was on the left side, postural deviation tended to the right. When the pain side was on the right side and vertebral body, postural deviation tended to the left. 3) There was no significant difference of postural deviation between regional pain in shoulder and regional pain in low back(p<0.01). Discussions and Conclusion. As a result, the pain, for sure, affected the good posture and its keeping process directly or/and indirectly. Therefore, as the postural deviation increases, the additional energy consumption increased by the works of the muscles to keep the good posture. Preponderated postural deviation, furthermore, could load too much to the musculoskeletal system, leading to increase the pain. The postural deviation, a result of the pain, can cause a secondary deformity of the distal area as a compensatory reaction, and this compensation actually become a cause of the musculoskeletal symptom back in a cycle. Therefore, the appropriate treatment of the musculoskeletal problem and the education of the posture correction should be given to decrease the pain, preventing the secondary deformities, and increasing muscle energy efficiency of the posture remaining muscles.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.90-95
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• 2009

The purpose of this study is to investigate industrial safety and health experts' opinions on the examination system of WMSDs(work related musculoskeletal disorders) risk factors. For doing this, a questionnaire study and two FGIs(focused group interview) were conducted. A questionnaire with open questions about the examination system was developed, and sent to 42 experts consented bye-mail. Of the experts, 24 experts responded, whose data were used in the analysis. The FGIs were performed for the persons in charge of industrial safety and health in industries and ergonomists. The questionnaire study revealed that most experts(91.3%) agreed with legalization of employers' duty for preventing WMSDs, necessity of the 11 tasks designated by Ministry of Labor, the examination system and ergonomics program, and pertinency for the examination system classification of periodic and occasional one. However, more than half experts disagreed with timeliness and appropriateness of the legal system. This was validated by the low approval rates for appropriateness of the 11 tasks, methods of the examination, charge person in the examination and ergonomics program. FGIs showed that it was desirable for the examination system to be legalized, and that the system was generally properly performed. It was suggested that the system be partially revised with reflecting problems disclosed during its enforcement rather than whole revision. It is expected that when revising relevant legal system, the results of this study would be used as valuable data.

• Journal of the Korean Society of Safety
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• v.21 no.4 s.76
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• pp.114-118
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• 2006

Recently, work-related musculoskeletal disorders(WMSDs) is one of the major issues in the shipbuilding industry. The number of injured workers has rapidly increased and demands for workers compensation, improvement of work condition and environment to prevent WMSDs become larger. To protect and reduce WMSDs in the shipbuilding industry, simulation technique which showed it's ability of increasing the manufacturing productivity will be applied, because simulation technique has the evaluation ability for a worker's danger level of production process by human activity analysis. In our research, we modeled worker's attitude and simulated worker's action. We evaluated the caution level, compared and analyzed the difference point of digital human which made on computer and actual worker's attitude to check feasibility of human modeling and simulation in the shipbuilding industry.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.67
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• pp.1-10
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• 2001

A series of studies with collaboration of university, research institute, and labor union were conducted to examine the situation and severity of work-related musculoskeletal disorders (MSDs) at an automobile company which is one of the three major car companies in Korea. As the first part of the study, a questionnaire survey was conducted on 4,000 employees at 2 different assembly sites and A/S centers over the country. The questionnaire was consisted of three parts; symptom survey, work environment information, and labor intensity survey. Among 4,000 questionnaires, 2,643 responses were considered for analysis. The result showed that 68.5% of the respondents complained pains on at least one part of the body and 48.8% on at least two parts of the body. After cross-sectional analysis of various information and risk factors such as severity of symptom, duration and frequency of pain, 31.5% of respondents were considered as at high risk of having MSDs. This high-risk rate showed similar result when compared with previous studies conducted at various manufacturing industries in Korea. Also the analysis of the work environment and job intensity survey supported the high-risk rate of MSDs.

• Journal of the Korea Safety Management & Science
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• v.22 no.2
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• pp.31-38
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• 2020

The study evaluated the accuracy and intra-rater reliability for OWAS (Ovako Working posture Analysing System), RULA (Rapid Upper Limb Assessment), REBA (Rapid Entire Body Assessment) to improve their evaluation accuracy and reliability. Participants (n = 163) with undergraduate degree were recruited in this study and trained for 6 hours about the ergonomic assessment methods. Ergonomic assessments were conducted using OWAS, RULA, and REBA for a representative work with dynamic posture found in manufacturing industries. The study compared action categories (overall level) and detailed evaluation scores for individual body part. Action categories of the participants significantly differed from the golden reference defined by ergonomic experts. The participants underrated or omitted scores for truck (37.4% of the participants) and legs (52.8%) in OWAS. Similarly, the participants underrated or omitted additional scores for all body parts except the hand and wrist in RULA (53.5%) and REBA (54.8%). On the other hand, the participants overrated scores for the hand and wrist in RULA (55.2%) and REBA (39.9%). The results found in this study can help of selecting focus points and parts during assessment and education to improve accuracy and reliability of the ergonomic assessment methods.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.728-735
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• 2022

Roofers get exposed to increased risk of knee musculoskeletal disorders (MSDs) at different phases of a sloped shingle installation task. As different phases are associated with different risk levels, this study explored the application of machine learning for automated classification of seven phases in a shingle installation task using knee kinematics and roof slope information. An optical motion capture system was used to collect knee kinematics data from nine subjects who mimicked shingle installation on a slope-adjustable wooden platform. Four features were used in building a phase classification model. They were three knee joint rotation angles (i.e., flexion, abduction-adduction, and internal-external rotation) of the subjects, and the roof slope at which they operated. Three ensemble machine learning algorithms (i.e., random forests, decision trees, and k-nearest neighbors) were used for training and prediction. The simulations indicate that the k-nearest neighbor classifier provided the best performance, with an overall accuracy of 92.62%, demonstrating the considerable potential of machine learning methods in detecting shingle installation phases from workers knee joint rotation and roof slope information. This knowledge, with further investigation, may facilitate knee MSD risk identification among roofers and intervention development.