• IE interfaces
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• v.10 no.3
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• pp.197-208
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• 1997

In workplace design, an ergonomic solution should ensure low postural stress in the operator during his/her work. Stress caused by awkward working postures of the trunk, shoulders and legs can result in fatigue, discomfort, musculo-skeletal disorders and nerve entrapment syndromes. Since discomfort and musculo-skeletal disorders are both related to exposure to biomechanical load on the musculo-skeletal system, minimization of discomfort will contribute to reduction of the risk for musculo-skeletal disorders as well. Therefore, in this study, perceived discomfort on the human body joints was measured in the standing postures using the magnitude estimation in order to have a standardized numerical scale for joint discomfort. Nine healthy graduate students participated voluntarily in the laboratory study. The results revealed that perceived discomfort of all the joints increased as the joints deviated from neutral position. Especially, it showed drastic increment on perceived discomfort when deviation from neutral position in each human body joint increased from 75% to 100%. in terms of relative range of motion(R0M). On the basis of these experimental results, a preliminary ranking for assessment of stressfulness of non-neutral postures around the human body joints was suggested.

• Journal of the Korea Safety Management & Science
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• v.12 no.1
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• pp.59-62
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• 2010

At the present time, Musculo-Skeletal Disorders breaks out and it is increased in a high speed. It is a serious problem for the labors and managements. People becoming greatly interested in it. It is caused by the labor intensity which is according to the work form, hours of labor, and the labors and the labor unions have a correct understanding in it, and the labor powers becoming older, and the change of divisional social environment which is latent. Before working do the simple preparation gymnastics or operate insensitive exercise remedy without scientific verification only in the present circumstances. Although operate the Work-related Musculo-Skeletal Disorders exercise remedy, it can not get a sufficient effectiveness. So the study develop one type of exercise remedy which are divided the upper limbs exercise remedy, the trunk exercise remedy, the lower limbs exercise remedy. It can be done without using any exercise equipments and regardless places. We should also enable the exercise remedy to be easily applied to workers who are in different circumstances. To use EMG to measure the burden of exercise remedy. By doing so, employees can easily do exercises and it will help to prevent and even can treat MSD. It is just the objective of the research.

• Journal of Biosystems Engineering
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• v.34 no.4
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• pp.286-294
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• 2009

A high prevalence of protected horticulture farmer's work-related musculo-skeletal disorders (MSDs) have been reported in precedent studies. One of the tasks required ergonomic intervention to reduce the musculo-skeletal risks is the task of product transporting. The purpose of this study is to evaluate quantitatively the spinal load of operator using manual vehicles to predict and prevent musculo-skeletal risks. Spinal load in operators using 4 kinds of manual vehicle were analyzed. Before evaluating spinal load on operator using the manual vehicles by bio-mechanical approach, it is needed to validate human model. In this study, ADAMS LifeMOD human model shows satisfactory results, comparing with already validated model's results or measured results. While Operators pushed the manual vehicles(wheelbarrow, Trolley, 2 wheel cart, and 4 wheel cart) contained loads that were 0 N and 800 N, their spinal loads(compression force, shear force) were evaluated. The compression force demonstrated under the NIOSH action limits - 3410N - for all 4 manual vehicle's operators(McGill 1997; Marras 2000). However, the lateral shear force demonstrated over the University of Waterloo - 500N - for all 3 manual vehicle's operators except 4Wheel cart (Yingline and McGill, 1999). Therefore, operators have risks in prevalence of the musculo-skeletal disorders due to shear force. The findings of this study suggest that it need to be determine the spinal load, especially lateral shear force in designing the manual vehicles in the future.

• Journal of Biosystems Engineering
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• v.36 no.1
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• pp.58-67
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• 2011

A high prevalence of protected horiculture farmer's work-related musculo-skeletal disorders (MSDs) have been reported in precedent studies. One of the tasks required ergonomic intervention to reduce the musculo-skeletal risks is the task of harvesting. The purpose of this study is to evaluate quantitatively the spinal load of worker harvesting with squatting posture to predict and prevent musculo-skeletal risks. Spinal load in Squatting posture with asymmetric trunk motion were analyzed. Before evaluating spinal load on harvesting worker by bio-mechanical approach, it is needed to validate human model. In this study, ADAMS LifeMOD human model shows satisfactory results, comparing with already validated model's results or measured results. While worker reached arms (20%, 40%, 70% arm reach) with various asymmetric trunk motion (0, 45, 90 degree), their spinal loads (extension, twisting and lateral bending moment) were evaluated. In case of extensor moment at lumbo-sacral joint, the more the arm reach got increased, the moment increased. however, in case of twisting moment and lateral bending moment, the more both arm reach and asymmetric trunk motion got increased, the moment increased significantly. The findings of this study suggest that it need to be determine the spinal load, especially twisting, lateral bending moment in evaluating musculo-skeletal workload in squatting posture.

• Journal of the Korean Society of Safety
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• v.14 no.4
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• pp.168-175
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• 1999

The objective of this research is to review the ergonomic keyboard developed to prevent musculo-skeletal disorders from being occurred during keyboard work. It was studied by comparing it with the traditional keyboard after analyzing and comparing the typing performance and work advantages both the two keyboards. Twelve male subjects with no history of musculo-skeletal disorders participated in the experiment. The quantitative data such as typing speed, accuracy, performance time, and the number of typing errors were obtained from the HTT software that was adjusted for this experiment. RULA worksheet and the degrees of extension and ulnar deviation on right and left wrist were used to analyze the upper body postures. The experiment results showed that the typing performance of the ergonomic keyboard decreased a little, but no significant difference statistically, compared with that of the traditional keyboard. On the work posture, the ulnar deviation during typing decreased in case of the ergonomic keyboard. But, the wrist extension was increased unexpectedly. Therefore, it can be regarded as these results occur due to the shape of wrist rest and the overall height of keyboard on a table. As a result, the reconsideration and redesign on the ergonomic keyboard are requested.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3552-3560
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• 2012

This study was conducted to find out the complaint rate of musculo-skeletal disorder and its related factors from male manufacturing workers at a nonferrous manufacturing industry. As for the research subjects, 302 workers selected from a nonferrous manufacturer located in Daejeon City, and as for the collection of data, a standardized anonymous questionnaire survey were conducted from May 1, 2011 to June 30, 2011. As a results, the complaint rate of musculo-skeletal disorders by each body part, the symptom of shoulders was 42.7%, the highest rate, followed by the waist, 36.8%, the neck and the hand/wrist/finger, 30.5% respectively, the leg and foot, 30.1% and arm/elbow, 20.9%. The complaint rate of musculo-skeletal disorder for the sociodemographic characteristics was significantly high as survey participants' age and BMI were low and in the group having low subjective health condition. The complaint rate of musculo-skeletal disorder for the health-related behavior characteristics was significantly high in the group having been absent from work due for diseases, in the group having received outpatient services, in the group having been hospitalized for treatment, in the group not having a regular exercise and in the group having insufficient sleeping hours. Finally, the complaint rate of musculo-skeletal disorder for the job-related characteristics was significantly high in the group suffering from the physical burden of their work, in the group working while bending at the waist and in the group carrying out repetitive tasks.

• Journal of Korean Library and Information Science Society
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• v.42 no.4
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• pp.243-262
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• 2011

The aim of this study was to investigate musculo-skeletal symtoms and working conditions of university library's librarians to search for the risk factors related to musculo-skeletal symptoms. The study subjects were 266 librarians who were working at 20 university libraries. A self-recording questionnaire was used to investigate the general characteristics, working conditions, job intensity, job satisfaction and stress, education of musculoskeletal disorders and nature of musculoskeletal symptom. Statistical analysis was done by using t-test and multiple regression analysis. The complaint proportion of self-reported positive musculoskeletal symptoms was 62.5% and that of severe musculoskeletal symptoms was 26.1%. Multiple regression analysis showed that low satisfaction of working conditions, high job intensity, irregular mealtime, job stress were closely related to the positive rate of musculoskeletal symptoms. Therefore, it will be necessary to make efforts to reduce the prevalence of musculoskeletal disorders improving working conditions and mitigating the job intensity.

• Journal of Korean Physical Therapy Science
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• v.10 no.2
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• pp.163-172
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• 2003

Background and Purpose. Physical therapists are at risk for work-related musculoskeletal disorders (WMSDs). Little understand the characteristics of work in physical therapist or the effort they take to prevent injury. The purpose of this study was to investigate the characteristics of work in physical therapist and the efforts for prevent injury Subjects. Standardized questionnaire was administered to 103 physical therapist in Pusan association. Methods. An questionnaire was given to each subject. Questions investigated the characteristics of work in physical therapist, efforts and caring of injury prevention. Chi-square Test used to assess the association of general characteristics with the characteristics of work in physical therapist. AVONA and T-test used to assess the association of efforts of prevent injury in independent variable Results. Physical therapist was reported a higher prevalence of WMSDs in most body areas. These attributes sometimes resulted in behaviors that contributed to the development of their WMSDs.

• Journal of the Korean Society of Safety
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• v.15 no.2
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• pp.136-142
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• 2000

One of the major requirements in preventing Work-related MusculoSkeletal Disorders(WMSDs) is to know definitely what vigorous exertion requirements are contained in a job. This requires improved job analysis tools which can accurately evaluate potentially harmful stresses to the musculoskeletal system. But to simply evaluate the level of stress at a joint, or in a muscle is not enough to motivate job changes. Therefore, the development of ergonomic evaluation tools for the jobs are important to ergonomics. The main objective is compared of the results that made by the ergonomic evaluation tools (e.g., BRIEF and RULA) in actually shoes manufacturing. These were developed in the foreign. So, it is priory needed to research of the ergonomics about Korean characteristic work by physiology and biomechanics.

• The Journal of Korea CHUNA Manual Medicine
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• v.4 no.1
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• pp.99-109
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• 2003

Dr. Lawrence H Jones developed innovative approach for the treatment of neuromuscular and musculo-skeletal disorders such as fibromyalgia, myofacial pain syndrome, any other muscle pain. This technique is called Strain/Counterstrain technique which uses effect of neuromuscular reflex for treatment of strain. First, Relieving spinal or other joint pain by passively putting the joint into its position of greatest comfort; secondly relieving pain by reduction and arrest of the continuing inappropriate proprioceptor activity. This was accomplished by markedly shortening the muscle that contains the malfunctioning muscle spindle by applying. mild strain to its antagonists. In other words, the inappropriate strain reflex is inhibited by application of counterstrain. Many other techniques have been developed for treating of muscle pain due to somatic dysfunction, but we want to introduce you to strain/counterstrain technique because this is basic concept and theory of Chum therapy for controling motor system.