• Journal of the Korean Society of Safety
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• v.14 no.3
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• pp.174-180
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• 1999

The objective of this study was to investigate the effects of carrying postures and weight of load carried one time on a worker when carrying heavy loads. Six male students participated in this study to perform a manual materials carrying task as subjects. To make comparison of work loads with physical work capacity, maximal oxygen uptake measurement tests were performed with submaximal test. The average oxygen consumption for the tasks of this study was 27.59~31.93% $VO_2$max. The results showed that the weight of load carried one time affects on working heart rate and oxygen consumption($VO_2$). It was found that the workload was significantly lower when handling a 20kg load at a frequency rate of 3times/min than when handling a 40kg load at a frequency rate of 1.5 times/min. There was no difference between carrying postures. It is concluded from the results of this study that the workload can be reduced by controlling conditions of a manual materials handling task.

• IE interfaces
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• v.16 no.2
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• pp.222-228
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• 2003

Computer-dominated jobs and industrial automation have rapidly created work-related musculoskeletal disorders(WMSDs) and WMSDs are also founded in employees of other general industries. WMSDs has been growing problems for Korean industries with higher incidence rate every year. The objective of this paper is to analyze the effects of the neck muscle workload according to postures(joint angle) and load weights. Seven male students participated in this study. Neck workload was rated on each person using a Borg's CR-10 scale. ANOVA showed that the CR-10 ratings were statistically significant according to postures and load weights. To reduce the large number and severity of WMSDs, which employees have been experiencing, we need to redesign the job in workplace so that we can control hazards that are reasonably likely to be causing or contributing to the WMSDs. The results of this study can be used to establish the safety criteria of joint angle and weight of neck workload.

• Proceedings of the ESK Conference
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• 1997.04a
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• pp.90-94
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• 1997

Many workers like welders are working in squat sitting postures with te object on the ground for an entire work shift. It is suspected that such prolonged squat sitting without any supporting stool would gradually cause musculoskeletal injuries to workers. This study is to quantitatively evaluate the physical stress caused by the prolonged squat sitting and to recommend a safe work/rest schedule for the task with squat sitting posture based on the lab experiment. In this study, 8 healthy student subjects participated in the experiment. They maintained a squat sitting posture for 16 minutes with 4 different stool height conditions: no stool, 10cm hight, 15cm height, 20cm height. Every 2 minutes, the discomfort was subjectively assessed using the magnitude estimation method for the whole body, lower back, upper leg and lower leg. Based on discomfort rating, we found that 10cm height stool relieved the workload most. Discomfort rating results also indicated that 20cm height stool showed the heghest workload, and that there was no difference in workload between 15cm height and no stool. We recommend to provide the workers with 10cm height stool for prolonged squat sitting tasks.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.4
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• pp.374-380
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• 2010

This paper proposes a wearable interface for a tendon-driven robotic hand prosthesis. The proposed interface is composed of a dataglove to measure finger and wrist joint angle, and a micro-control board with a wireless RF module. The interface is used for posture control of the robotic hand prosthesis. The measured joint angles by the dataglove are transferred to the main controller via the wireless module. The controller works for directly controlling the joint angle of the hand or for recognizing hand postures using a pattern recognition method such as LDA and k-NN. The recognized hand postures in this study are the paper, the rock, the scissors, the precision grasp, and the tip grasp. In experiments, we show the performances of the wearable interface including the pattern recognition method.

• Journal of the Ergonomics Society of Korea
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• v.29 no.3
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• pp.331-336
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• 2010

The purpose of this study was to identify the effect of the craniocervical posture on swallowing and hyoid bone movement with sitting posture in wheelchair, and to provide basic data for developing a treatment program for dysphagia. A total of sixty healthy adults without a history of dysphagia who were guardians or care assistants of inpatients at Hospital K underwent video fluoroscopy performed by physiatrists from April to July 2009. The results of the fluoroscopy were analyzed based on the measurement of hyoid bone movements. The hyoid bone movement(horizontal, vertical, and diagonal) was significantly high in the neutral craniocervical, chin-tuck, and sixty degrees extension postures, in descending order(p<.05). It was found that the neutral craniocervical posture is the most effective posture for hyoid bone movement with sitting posture in wheelchair.

• Journal of the Korean Home Economics Association
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• v.20 no.3
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• pp.1-8
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• 1982

In this study, we attempted to make an original pattern of clothing for an abnormal type of figure, especially for the type of kyphosis. We measured the curvature of the spine of a woman with kyphosis with a Martin measuring instrument and a silhouetter in the following ways. First, we counted the rate of shrinkage of the standard lines drawn on the surface of the body according as the body moved. Secondly, placing the front and back darts, the front and back shoulder darts and the side darts according to“Munhwa”pattern, we made cubic cuttings of four moving postures as well as the standing one. Thirdly, we superposed the developed patterns of the standing and the moving postures, measuring the position change and the amount to the change of the darts, and compared them. The results are as follows: 1) In the developed pattern of a cubic cutting of the basic pattern and the standing posture, the neckhole became larger than that of the basic pattern, and the waist line was lowered than that of the basic pattern because the center back line was shortened due to the curved backbone.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.151-157
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• 1996

Postural tremor of the upper arm in a static posture was measured to provide guidelines of hand tool weight. Three types of camera recording postures were selected. Postural tremor was measured on five levels of tool weights; no weight, 400g, 800, 1200g, and 1600g. For each conditions, upper arm postural tremor was measured together with EMG of biceps, deltoid, and pectoralis major, and Borg's CR-20 scale ratings of perceived exertion. Results of the experiment are as follows; Frequency analysis of tremor revealed that increased amplitude of frequency band of 2-4Hz and 10-14Hz was observed. Postural tremor of the upper arm maintained the initial level until fatigue developed. After the development of fatigue, the rate of the change of postural tremor was significantly increased. Different tool weights and hand postures showed different rate of tremor increase. And time to fatigue and the corresponding endurance time was positively correlated with Borg's RPF scores.

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.178-182
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• 2000

The purpose of this study is to investigate the train seat dimensions suitable for keeping comfortable postures. We designed a special experimental seat of which the lengths and angles are adjustable separately. Seat dimensions keeping subjects comfortable were measured for the restricted posture and the extended posture. The significant differences of dimensions fur two postures were analyzed, and the differences were found on backrest-seatpan angles, length of backrest and so on. The dimension differences fur the levels of height and weight were also found out. Some dimensions were correlated with subjects' height and weight..

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.138-143
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• 2000

This paper addresses experimental results carried out to investigate the transmission of seat vibration to the head for Korean. Vertical seat vibration in the frequency range of 0.5-30 Hz was applied to a seated Korean male subject. To examine the intra-variable effects on transmissibility, five different postures and three different vibration excitation levels were considered. The applied acceleration and head accelerations of the seated subject were measured simultaneously by using a 6-axes bite-bar. Detailed experimental results of measured transmissibilities are illustrated for each posture and/or vibration excitation level. They are found to allow the identification of dynamic characteristics of Korean seated body for various real vibration environments. Furthermore, they are expected to be very useful in designing new seats for automotive and railway vehicles and in improving their vibration ride quality.

• The korean journal of orthodontics
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• v.22 no.1
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• pp.169-177
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• 1992

This investigation was carried out in order to find out changes in head postures and in craniofacial morphology, in relation to the inclination of cervical column. For this study 85 subjects, consisting 39 males and 49 females, between the ages of 7 to 24 years old were chosen, and following results were observed after analysing the correlation coefficients between each structures. 1. No definite relationships were observed between the inclination of cervical column (CVT/HOR) and the inclination of anterior cranial base (SN/VER) 2. No definite relationships were observed between the inclination of mandibular ramus (RL/HOR) and the inclination of mandibular inclination (MLP/VER). 3. In subjects with anteriorly inclined cervical column, increase in mandibular plane inclinations (ML/VER) were observed. 4. No definite relationships were observed between the inclination of cervical column (CVT/HOR) and changes in palatal plane (NL/VER).