• 산업경영시스템학회지
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• 제21권48호
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• pp.253-262
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• 1998

The purpose of this study is to suggest prevention methods for the health of VDT workers by an ergonomic survey and analysis of body discomfort. Totally 150 VDT workers(male; 78, female; 72) were investigated with questionnaire. From the results of survey, average of the subjects age was 28.5 years(male; 29.7, female; 27.2), average working period was 5.4 years(male; 5.2, female; 5.6), average VDT working hours was 6.3 hours(male; 6.2, female; 6.4) and workers who answered that they use VDT for more than 5 hours a day were over 79%. Among the questionnaires 10.7% and 7.3% of VDT workers complained the discomfort of their neck and lower back, respectively. VDT workers responded that the height of chair, keyboard and computer monitor were the main reasons for feeling discomfort. The results suggest that the VDT syndrome prevention program should be developed for safety and health of the VDT workers.

• 대한인간공학회지
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• 제34권2호
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• pp.167-177
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• 2015

Objective: The objective of this research is to develop evaluation checklist for personal office furniture and apparatus to shape comfortable and efficient worksite for workers' welfare improvement, productivity enhancement and labor force preservation, and to identify office work environment by applying the checklist. Background: Because most office workers work using computers in a sitting posture, the ratio of office workers among total musculoskeletal disorders patients is forecast to increase. In this regard, an effort to prevent and manage such musculoskeletal disorders is required. Method: This research developed evaluation checklist for personal office furniture and apparatus by examining 25 domestic and international ergonomic literature and anthropometric data. This research carried out a fact-finding survey targeting the A Office and B Office of one public agency using the checklist. Results: Although, the checklist items on desks, chairs, computers and other goods conformed to the checklist standards, the following items did not conformed: desk height adjustment, seat board depth adjustment, lumbar support depth, foot rest, wrist rest, mouse tray, headset, speaker phone and Bluetooth. Conclusion: The evaluation checklist for personal office furniture and apparatus and fact-finding survey results are considered to be used as basic data for office work environment and workers' welfare improvement. Application: The information drawn from this research can be helpful to manufacturers' design and manufacture of ergonomic furniture and apparatus.

• Safety and Health at Work
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• 제10권3호
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• pp.314-320
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• 2019

Background: Sitting posture may be related to risk factors, including inadequate weight-bearing support, particularly when maintained for long periods. Considering that body weight is loaded in a closed support system composed of the seat, backrest, floor and working surface, the aims of the present study were to describe the development of an ergonomic sitting workstation to continuously record weight-bearing at the seat, chair, backrest, work surface, and floor and to test its measurement properties: reproducibility, criterion-related validity, and sensitivity. Methods: Rigid bodies (1 to 30 kg) and participant weights were recorded to evaluate the workstation measurement properties. Results: Rigid body tests showed variation values less than 0.050 kg on reproducibility test and errors below 5% of measured value on criterion validity tests. Participant tests showed no statistically significant differences between repeated measures ($p{\geq}0.40$), errors were less than 2% of participant weights an sensitivity presented statistically significant changes (p = 0.007). Conclusion: The sitting workstation proposed showed to be reliable, valid and sensitive for use in future ergonomic studies to evaluate the sitting posture.

• 한국산업보건학회지
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• 제19권1호
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• pp.16-24
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• 2009

This research aims to measure and analyze the dimensions of typical office chairs and desks sold in domestic market, and to suggest the modifications of national guidelines considering Korean peoples' body characteristics. The scope of this study was limited to the desktop type of computer jobs, excluding laptop environment. The dimensions of 24 different office chairs and 7 tables were measured, and their dimensions were analyzed against the Ministry of Labor (MOL) Notification and Korean Standards (KS). At the same time, the data from the Size Korea was also considered. As a result, the KS guidelines were overall fulfilled by the measured products, while the MOL Notification was not. It was found that the guidelines on the chair height, seat pan depth, lumber support height, and armrest height need to be modified. Some inconsistencies between the MOL Notification and KS were also found. It is suggested that the required dimensions specified by both guidelines should be unified.

• 디자인학연구
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• 제12권3호
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• pp.73-80
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• 1999

국내의 의자 개발은 선진외국의 인체치수 및 설계기준에 의한 디자인으로 인해 많은 사용자가 작업 수행도는 물론, 허리, 목, 어깨 통증에 대한 호소가 늘고 있는 실정이다. 다양한 체격의 사용자가 무리없는 자세로 사무작업을 수행하기 위해선 사무용의자의 각종치수에 대한 인간공학적 설계기준이 필요하다. 본 연구에서는 한국인 성인 인체측정자료를 바탕으로 선 연구의 설계지침을 이용하여 설계권장치수를 제시하였다. 이에 대한 타당성 검증을 위해 피실험자들을 측정하여, 선호치수를 구하였고, 그것과 설계지침에 따른 차이를 분석하였다. 그리고 일반적으로 많이 사용하는 사무용의자들과 자신의 신체에 맞게 조절가능한 의자를 사용하여, 안락감과 신체불편도를 평가하였으며, 각 설계치수가 인체에 미치는 영향을 비교 분석하였다. 좌면의 높이가 높으면 허벅지에 영향을 미치고, 등받침대 폭, 높이, 각도는 어깨, 목, 허리에 피로를 가져다준다.본 연구실험결과 한국인을위한 사무용의자의 좌면 높이 권장치수는 고정식일때 425mm, 조절식일때 365-484mm를 추천한다. 그 외 설계권장치수는 논문에 제시하였으며, 이와 같은 인간공학적 설계권장치수는 결론적으로 사용자의 신체에 맞게 조절범위를 제공하므로 설계분야에 중요한 기초자료가 되리라 본다.

• Journal of Preventive Medicine and Public Health
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• 제26권1호
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• pp.20-36
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• 1993

Work-related low back pain is one of the major factors that cause the loss of working power especially in actively working age, therefore controlling the work-related low back pain is one of the major issues in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the efficient control program of the work-related low back pain. The subjects were male workers employed at the manufacturing industry in Pusan with longer than 6 months' working duration. The data was collected by self-reported questionnaire and interview from May 1 to October 31,1992. The contents of questionnaire were as follows:. the experience of low back pain within the recent one month, general characteristics(age, marital status, education level, religion, regular exercise), physical characteristics(height, weight), employment status(working duration, daily working hours, rest during work, satis(action fur the job), type of work and working environments(posture, forward bending, lifting and movement, satisfaction for table and chair). The result was analyzed for 608 entire respondents by case-control comparative method. The number of cases was 152 with a history of work-related low back pain, so the relative frequency of self-reported work-related low back pain was 25.0%, and the number of controls was 344 without any history of low back pain. As a result, two characteristics of the employment status(working duration, satisfaction fur the job) and all characteristics of type of work and working environments showed a statistical significance between the case and control groups(p<0.01). The Oddb ratios of these variables for Work-related low back pain were calculated. They were 7.88 for the satisfaction fur chair, 7.86 for lifting and movement,3.31 for satisfaction for table, and 2.22 fur bending forward(p<0.01). And for the multivariate logistic regression analysis confirmed that unsatisfaction for table was independent risk factor for Work-related low back pain. In summary, though this study was based upon the self-reported questionnaire and the subjective complaints, the satisfaction for chair, lifting and movement, satisfaction for table, and bending forward concerned with the type of work and working environments were considered as the main factors causing the work-related low back pain, and the work-related low back pain may be preventable by the ergonomic control of these factors.

• 대한기계학회논문집A
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• 제34권2호
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• pp.167-174
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• 2010

본 논문에서는 사무용 의자의 틸트 동작시 요추지지 기능과 등의 미끄럼을 평가함으로써 등판 회전중심의 최적 위치를 연구하였다. 이를 위해 인체와 의자로 이루어진 수학적 모델을 이용하여 틸트 동작 시뮬레이션을 수행하였다. 착석된 인체 모델의 측면 상에서 고관절 중심을 포함한 42개의 위치에 등판 회전축 위치를 설정하고 각각 시뮬레이션을 수행하였다. 또한 등판의 회전중심이 고관절에 위치한 의자 시작품과 좌판하부에 위치한 기존의 의자에 대해 동작분석 실험도 함께 수행하였다. 시뮬레이션 결과 등판의 회전중심이 고관절 중심에 가까이 위치할수록 틸트시 요추각도 변화량과 등의 미끄럼거리는 작아졌다. 한편 실험결과 착석자의 등과 등판사이의 이격변위와 미끄럼변위는 등판의 회전중심이 고관절 위치에 설계된 시작품에서 더 작게 측정되었다. 시뮬레이션과 실험결과로부터 등판의 회전중심이 인체의 고관절 위치에 가깝게 설계되면 틸트시 착석자의 요추를 효과적으로 지지해 줄 수 있음을 알 수 있었고 이때 착석자는 보다 편안하고 건강한 착석자세를 유지할 수 있다. 이 결과는 사무용 의자에서 등판 회전축 위치의 인간공학적 설계를 위한 가이드라인을 제공한다.

• 한국산업보건학회지
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• 제7권2호
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• pp.289-297
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• 1997

Work-related low back pain(below LBP) is one of the major cause of morbidity, disability, limitation of activity and economic loss. Therefore the work-related LBP is one of the major issue in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the effective control programs of work-related LBP. The subjects were male workers employed at the welding and metal factory. The data was collected by self-reported questionnaire, interview and checking abdomen muscular and grasping power for two days on October, 1993. The contents of questionnaire were as follow: the experience of LBP, general characteristics, physical characteristics, employment status, type of work and working environment. The number of cases was 104 with a history of work-related LBP, so the prevalence of work-related LBP was 35.0%, and the number of controls was 140 without any history of LBP. As a result, marital status, educational level, abdomen muscular power, tenure, category of job, satisfaction of job, working posture, satisfaction for table and chair and lifting materials showed a statistical significance between the case and control groups. 284 Lifting jobs were quantified by NIOSH lifting equation method and ergonomic computer modelling methods. There were no significant differences in the action limit and disc compression force between group with LBP and without LBP. But in the lifting frequency and cumulative disc compression force there were significant differences. Therefore work-related LBP should be prevented by the ergonomic and environmental control.

• 환경위생공학
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• 제21권4호
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• pp.19-28
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• 2006

The purpose of this study was to investigate the related factor for the prevalence of musculoskeletal symptoms among 212 sewing worker. The survey was performed with self-administered questionnaire for the risk factors related to musculoskeletal disorders(MSDs) from August 5 to 7 in 2005. The prevalence of musculoskeletal symptoms were 75.8% and the those of the local symptoms were 71.7 % for shoulder, 60.4 % for neck, 35.8 % for arm and 50.9 % for wrist. The risk factors related the self-reported MSDs had not shown in general characteristics. But, there was a significant difference between daily working hour and wrist, working speed and neck, the degree of satisfaction and wrist for work related factor. Also, it was shown the significant difference between chair height and neck, the height of sewing machine and wrist among the space below work station, neck, waist for the prevalence of musculoskeletal symptoms. The significant correlation was shown for daily working hour and wrist, working speed and arm, work load and shoulder and the degree of satisfaction and arm for work related subjective symptom. Considering above results, it is suggested the ergonomic design be provided to working hour, the height of chair and work station as well as daily working hour even there is a significant difference for the prevalence of symptoms in each body part for sewing workers.

• 한국전문물리치료학회지
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• 제16권3호
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• pp.42-49
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• 2009

This study examined the vastus medialis oblique (VMO) and the vastus lateralis (VL) onset time differences (OTD) during quadriceps contraction in different hip positions. Twelve healthy subjects were recruited (four men, eight women). Surface EMG activities of the VMO and VL were measured during a quadriceps strengthening exercise in a long sitting condition and in a sitting at a chair with feet hanging condition. For each condition, subjects were tested in two hip positions (neutral and adduction). The OTD between the two muscles was calculated for each condition, by subtracting the onset time of the VL from the VMO. Therefore, the negative value of OTD represent earlier EMG onset of the VMO compared to the VL. The OTD was not significantly different between the hip neutral and the hip adduction position in the long sitting condition (p=.064). However, the OTD was significantly different between the hip neutral position ($15.83{\pm}109.51$ ms) and hip adduction position ($-5.58{\pm}121.08$ ms) during the sitting at a chair with feet hanging condition (p=.047). The negative OTD value in the hip adduction condition during quadriceps strengthening exercises is the result of earlier onset of the VMO than VL. Therefore, quadriceps contraction in the hip adduction position can prevent the risk of patella lateral tracking. We expect that quadriceps strengthening exercise in the hip adduction position will be a safe way to prevent patellofemoral pain syndrome resulting from abnormal patella lateral tracking.