• 한국치위생학회지
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• 제15권4호
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• pp.649-659
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• 2015

Objectives: The purpose of the study is to investigate the musculo-skeletal pain prevalence and severity in the dental hygienists based on PRECEDE model. Methods: A self-reported questionnaire was completed by 483 dental hygienists in Gwangju from September 13 to October 12, 2013. Data were analyzed by frequency analysis, chi-square test, t-test, and multiple logistic regression analysis using SPSS 18.0 program. Musculo-skeletal pain severity was classified from 1 to 5 by PRECEDE model. The questionnaire consisted of six questions of the general characteristics of the subjects, one question of musculo-skeletal pain prevalence, one question of body part musculo-skeletal pain prevalence, one question of subjective health status, three questions of activities of daily living, six questions of working environment, one question of musculoskeletal system diseases knowledge, two questions of social support, two questions of education experience and data use method, and five questions of necessity of health education. Results: The prevalence rate of musculo-skeletal pain within a year was 83.9% and 22.8% of the dental hygienists complained of severe pain. The odds ratio of moderate pain severity was 1.99(95% CI, 1.10-3.60) and the odds ratio of unhealthiness was 3.27 (95% CI, 1.35-7.94). The odds ratio of pain severity in those working for 4-6 years was 0.21(95% CI, 0.08-0.57). The odds ratio of pain severity in those practicing 6-10 scaling cases per day was 0.33(95% CI, 0.17-0.65). The odds ratio of pain severity in wrist turning and bending was 3.56(95% CI, 1.19-10.62). Conclusions: The muscolu-skeletal pain severity in the dental hygienists was closely associated with subjective health condition, work duration, the number of scaling practice activity, and a treatment posture. Regular physical checkup for the dental hygienists will improve the musculo-skeletal pain due to scaling practice.

• Journal of Biosystems Engineering
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• 제34권4호
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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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• 제36권1호
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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.

• 한국정밀공학회지
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• 제22권11호
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• pp.7-15
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• 2005

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.2155-2156
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• 2006

The purpose of this work is to investigate the fundamental properties of the gradual muscle force potentiation for the prediction of muscle force and body movement from the stimulation input with musculo-skeletal model. We investigated the dependence of force potentiation on both the pulse-amplitude and the pulse-duration. The experimental result showed that the force increment ratio during electrical stimulation decreased with pulse-amplitude. The force increment ratio decreased with short pulse-duration and was maintained to be constant with pulse-duration longer than $500{\mu}s$. A new model of the muscle potentiation based on these results is desired in the future.

• 보건행정학회지
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• 제12권1호
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• pp.125-143
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• 2002

The objectives of this study were analysis of patient\`s characteristics and market segmentation in oriental medical care and western medical care. This study focused on medical utilization using Anderson's health utilization model. The source of data was 1998 National Health and Nutrition Survey which Korean Institute For Health and Social Affairs carried out. A stratified multistage probability sampling design was used in this survey. The analysis was conducted using the statistical software package SPSS version 10.0 and Answer Tree 2.1 which is one of data mining methodology. The results were as follows ; 1) 44.9% of respondents reported visiting oriental medical center within recent two weeks. 3.4% of them used oriental medical care. The group of age, kind of disease and medical expenditure are associated with the difference western and oriental medical utilization rate. 2) There were several factors related to utilization of oriental medical care according to decision tree. Especially, important factors that patient chose his medical center were kinds of disease, kinds of common medical use, and expenditure. 3) in the results of CART analysis, market of oriental medical care were classified by seven categories. The major groups who have a preference for oriental medicine were those musculo-skeletal, cerebra-vascular disease, or chronic headache patients, and they had a preference fur oriental medical care in common use. These results show that oriental and western medical market were divided into various areas by market segmentation.

• 한국정밀공학회지
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• 제22권6호
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• pp.207-212
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• 2005

The purpose of this work is to develop the FES controller that can cope with the muscle fatigue which is one of the most important problems of current FES (Functional Electrical Stimulation). The feasibility of the proposed FES controller was evaluated by simulation. We used a fitness function to describe the effect of muscle fatigue and recovery process. The FES control system was developed based on the biological neuronal system. Specifically, we used PD (Proportional and Derivative) and GC (Gravity Compensation) control, which was described by the neuronal feedback structure. It was possible to control of multiple joints and muscles by using the phase-based PD and GC control method and the static optimization. As a result, the proposed FES control system could maintain the cycling motion in spite of the muscle fatigue. It is expected that the proposed FES controller will play an important role in the rehabilitation of SCI patient.

• 비파괴검사학회지
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• 제31권5호
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• pp.494-499
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• 2011

인체 근골격 시스템에 대한 다물체 동역학 모델을 이용한 동작중의 인체 내부의 생체역학 분석 및 평가 기술에 대하여 기술하였다. 의료영상과 사체실험 결과를 기본으로 하는 인체 다물체 동역학 모델과 3차원 동작분석 시스템을 이용한 인체 동작분석기술을 이용하여 생체내 발생하는 관절기구학, 관절모멘트 관절접촉력 및 근력을 예측하는 기술을 보행과 팔굽혀펴기 두 동작에 적용하였다. 본 연구에서 개발한 인체 다물체 동역학 모델링 기술과 3차원 동작분석기술은 다양한 동작을 수행하는 생체의 분석 및 평가 기술로 활용성이 높을 것으로 생각한다.

• 대한기계학회논문집A
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• 제35권7호
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• pp.785-790
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• 2011

본 연구에서는 인체의 하지부를 다물체 시스템으로 모델링하여 무릎관절에 걸리는 구속력의 불확실성을 추정하였다. 일반적으로 근육의 기계적인 특성은 Hill-type muscle model 이 사용되며 여기에 적용되는 인체의 특성과 해부학적인 데이터는 지난 십 수년 동안 크게 발전되었다. 그러나 정확하게 그것들을 안다는 것은 불가능하며 개인마다 다른점을 고려해야 할 필요가 있다. 본 논문에서는 Hill-type muscle model 과 함께 인체의 해부학적인 데이터를 통계 방법론을 이용하여 무릎 관절에 걸리는 구속력의 불확실성을 추정하였다. 초기 앉아있는 자세에서 일어서는 과정에서 작용하는 구속력을 추정하였으며 이때 인체 하지 근육의 특성을 musculoskeleton-actuator 를 이용하여 해석하였다.

• 한국운동역학회지
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• 제25권1호
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• pp.29-37
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• 2015

Objective : The purpose of this study was to investigate the biomechanical properties of shock absorption strategy and postural stability during the drop landing for each types. Methods : The motions were captured with Vicon Motion Capture System, with the fourteen infra-red cameras (100Hz) and synchronized with GRF(ground reaction force) data(1000Hz). Ten male soccer players performed a drop landing with single-leg and bi-legs on the 30cm height box. Dependent variables were the CoM trajectory and the Joint Moment. Statistical computations were performed using the paired t-test and ANOVA with Turkey HSD as post-hoc. Results : The dominant leg was confirmed to show a significant difference between the left leg and right leg as the inverted pendulum model during Drop Landing(Phase 1 & Phase 2). One-leg drop landing type had the higher CoM displacement, the peak of joint moment with the shock absorption than Bi-leg landing type. As a lower extremity joint kinetics analysis, the knee joint showed a function of shock absorption in the anterior-posterior, and the hip joint showed a function of the stability and shock absorption in the medial-lateral directions. Conclusion : These findings indicate that the instant equilibrium of posture balance(phase 1) was assessed by the passive phase as Class 1 leverage on the effect of the stability of shock absorption(phase 2) assessed by the active phase on the effect of Class 2 leverage. Application : This study shows that the cause of musculo-skeletal injuries estimated to be focused on the passive phase of landing and this findings could help the prevention of lower damage from loads involving landing related to the game of sports.