• 대한인간공학회지
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• 제26권2호
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• pp.35-44
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• 2007

Work-related musculoskeletal disorders (WMSDs) are a major problem in industries in which manual materials handling is performed by workers. To prevent these WMSDs, it is necessary to understand the muscular strength capability and use this knowledge to design job and selection and assignment of workers. Even though two-hands lifting activity of manual materials handling tasks are prevalent at the industrial site, many manual materials handling tasks which require the worker to perform one-hand lifting are also very common at the industrial site and forestry and farming. However, a few researches have been done for one-hand lifting activity of manual materials handling tasks. The objective of this study is to compare one-hand and two-hands lifting strength in terms of static and dynamic strength of the lifting activity for the ranging from the height of knuckle to elbow. It is shown in this study that the isometric lifting strength of one-hand is ranging from 54.7 to 63.3% of the one of two-hands. However, it is found that there is no significant difference between a person's isometric lifting strength for left-hand and right-hand. It is also shown that there is no significant difference between the peak force under the dynamic sub-maximal loading with one-hand and two-hands lifting activity. Similar results were obtained for the peak acceleration and peak velocity under the dynamic sub-maximal loading with one-hand and two-hands lifting activity. Isometric lifting strength at the height of knuckle was ranging from 2 to 3 times of the dynamic peak force during sub-maximal lifting. It is concluded that the dynamic peak forces under the sub-maximal loading are not highly correlated with the isometric lifting strength in similar postures.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 V
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• pp.2827-2830
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• 2003

Tele manipulator is distingushed from industrial robot by iterating same specified work. Manipulator operator is included in control loop for controlling the telemanipulator because he decide directly during the work and order controllabily reducing the modelling error of telemanipulator which depend on the PID controller. But position-force control method of bidirectional control impose unsafety of vibiration and Analytic Hierachy Method can stabilize for reducing nonlinear modelling error by expert operator because of transformation empirical control rule to linear model.

• The Journal of Korean Physical Therapy
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• 제10권2호
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• pp.77-86
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• 1998

The shoulder joint permit ate greatest mobility of any joint area carries out the importment function of stabilization for hand use. So handgrip activity is important to evaluate while assessing shoulder load in manual work. There was an association between static handgrip and shoulder muscle activity. The purpose of this study was to find out the changes of the hand grip strength according to shouter an81e. One hundred (50 female, 50 male) college adult volunteers with no known shoulder dysfunction participated subject in three positions with elbow extension: (1) shoulder $0^{\circ}$ flexion (2) shoulder $90^{\circ}C$ flexion (3)shoulder $180^{\circ}C$ flexion. The paired t-test was used to determine the different in grip strength between right and left hand at shouter position change. All, there was significiant for all three position by right and left shoulder (p<0.001). In mon, the ANOVA results revealed not a significiant F-ratio fer all three position by right and left hand. In woman, revealed significiant (p<0.05).

• Journal of the Korean Statistical Society
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• 제32권3호
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• pp.311-311
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• 2003

This paper contains the following errors. 1. "$I_{\{x>D\}}{\lambda}dt_{p0}(t)s(x)$" should be added to the right hand side of (2.3). 2. "$I_{\{x>D\}}{\lambda}_{p0}(t)s(x)$" should be added to the right hand side of (2.6). 3. "$I_{\{x>D\}}{\lambda}_{p0}s(x)$" should be added to the right hand side of (2.9). 4. In Theorem 2.3 and its proof, "${\lambda}{\int}_{0}^{D}f(y)s(x-y)dy$" appears three times (including one in (2.20)). To each of these, "${\lambda}_{po}s(x)$" should be added. 5. In Remark 2.5, "${\lambda}dt_{p0}/s(x)dx" should be added to "${\int}_{0}^{D}{\lambda}dt\;s(x-y)dxf(y)dy$". As a result of these corrections, a simpler proof of Theorem 2.3 becomes available. Substituting (2.18), (2.21), (2.22) into the left hand side of (2.20) and comparing the result with (2.10), we have the right hand side of (2.20).

• 대한인간공학회지
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• 제15권2호
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• pp.51-62
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• 1996

This research utilized the psychophysical methodology, where secrw drivers are used, to determine the effects of i) the location and orientation of work objects, and ii) wearing gloves, on ratings of perceived exertion at various body parts. The validity of the psychophysical methodology in determining a preferred work pace was also studied. The subjects drove screws with a screw driver into thick wooden sheet at three vertical and three horizontal locations. They drove serews for 3 minutes at each location and assessed the condition using the psychophysical scale. The results showed that only the vertical location was a significant factor in determining the discomfort ratings. Driving screws at elbow height on the vertical surface and with the lower arm close to the body on the horizontal surface were the work locations with the smallest ratings of perceived discomfort. Wearing gloves had significant effects on reducing the pain of the hand. From the experiment in which a comfortable work pace was identified using 20 minute psychophysical adjustment, it was found that the psychophysical method is sensitive to workers perception of the physical stress when the upper limbs are employed. This was confirmend by the high correlation between the psychophysical results and EMG measurement.

• 대한인간공학회지
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• 제22권4호
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• pp.15-25
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• 2003

Recent studies indicate potential links between various psychosocial factors and work-related musculoskeletal disorders (WMSDs). In this research, the effects of job stressors on the WMSDs symptoms were investigated using questionnaire in the largest automotive company in Korea. It was found that perception of workload, over time and shift work, and working using powered hand tools were significant factors for the symptoms of WMSDs, along with smoking habit, periodic exercise, and interpersonal relationship. Practical applications of this research include practitioners taking into account psychosocial work factors and job stress in their efforts to reduce and control WMSDs.

• 한국직업건강간호학회지
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• 제18권2호
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• pp.270-280
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• 2009

Purpose: This study was conducted to examine the relationship between job stress and work-related musculoskeletal symptoms of hospital nurses. Method: The questionnaires were administered to 290 nurses working in a general hospital located in S city from September 1 to 15, 2008. The data were analysed with descriptive statistics, and logistic regression test by SPSS WIN 14.0. Results: With the NIOSH criteria 1, the musculoskeletal symptoms were prevalent in 66.8% of the subjects. The musculoskeletal symptoms by body parts appeared mostly on leg/foot(40.6%) and followed by shoulder (38.7%), waist(30.3%), neck(23.6%), hand/wrist/finger(14.0%) and arm/elbow(4.4%). There were statistically significant differences in prevalence rate of musculoskeletal symptoms by age, work department, career and job stress. Conclusion: When developing a management program for musculoskeletal symptoms of hospital nurses, it is necessary to fully understand nurses' work considering each hospital's nursing administration system.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.57-58
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• 2012

Work to repeat the work using the tool since many occupational diseases such as musculoskeletal disorders, such as occupational low back pain is increasing. To solve this problem, previous(or existing) studies for improving the environment of construction workers are working, but the previous study was lack of approach that applied to condition of construction field. Thus, the objective of this paper will analysis the Correlation of musculoskeletal disease which is caused by Working Hand and Working Type for workers. The results of this Research through a die to improve the work environment of workers and prevention of musculoskeletal disorders in order to prepare is to provide basic data.

• 지능정보연구
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• 제2권1호
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• pp.93-107
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• 1996

A flexible flow line(FFL) consists of several groups of identical machines. All work-orders flow along the same path through successive machine groups. Thus, we emphasized the balancing of workloads between machine groups in order to maximize total productivity. On the other hand, many different types of work-orders, in varying batch or lot sizes, are produced simultaneously. The mix of work-orders, their lot sizes, and the sequence in which they are produced affect the amount of workload. However, the work-orders and their lot sizes are prefixed and cannot be changed. Because of these reasons, we have developed an optimal route selection model using heuristic search and Min-Max algorithm for balancing the workload between machine groups in the FFL.

• 한국안전학회지
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• 제38권6호
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• pp.16-25
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• 2023

This study investigated health problems and work-relatedness for fishermen. In total, 121 fishermen (103 males and 18 females) were extracted from the data of the 6th Korean Working Conditions Survey. Two groups (Symptomatic and Asymptomatic) were statistically compared in terms of health problems and exposure to hazards. The most common health problems identified for fishermen were muscular pain in the shoulder, neck, and upper limbs (73.6%), backache (71.1%), muscular pain in the lower limbs (58.7%), overall fatigue (33.9%), headaches or eyestrain (22.3%), and anxiety (8.3%). These health problems were found to be related to the working conditions of the fishermen (low temperatures, tiring or painful postures, stance, sitting position, repetitive hand or arm placement, and the experience of stress). This study's findings may help us better understand the characteristics of the health problems and work-relatedness of fishermen and could be helpful for improving fishermen's overall health and safety.