• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1998년도 춘계학술대회논문집
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• pp.36-39
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• 1998

In this study, the postural stresses in automobile assembly tasks were evaluated through an experiment. We had 19 subjects who simulated 42 different working postures occuring in the automobile assembly tasks for1 min and rated their whole body discomforts subjectively. We sued a free modulus magnitude estimation technique, commonly used as a psycophysical rating technique, and fully trained the subjects for the technique. The postures were selected through the analysis of the characteristics of te automobile assembly tasks and the expected difficulties. The subjective discomfort rating data were normalized by min-max standardization method. The consistency of the rating data was guaranteed by the analysis of spear man rank-order. The postures were ranked on their ratings and the relationships between the whole body discomfort ratings, and joint discomfort ratings were analysed. It is expected taht a system for evaluating postural stresses, which was specific to automobile assembly tasks, can be developed based on the relationship and can also be expended to a general purpose system with a minor modification.

• International Journal of Human Ecology
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• 제14권1호
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• pp.41-55
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• 2013

The purpose of this study was to analyze human upper body surface changes at the shoulder and back area. The body surface data were analyzed in terms of muscle and bone displacement in dynamic postures. Body surface data were collected with a 3D body scanner. The body surface was scanned at the static and four baseball batting postures. The body surface dimensions over the deltoids, scapulae and trapezius were measured. The results show that the vertical measurements of the deltoids increased by 20%. The horizontal measurements of the axilla of the back increased. The surface of the trapezius was elongated by over 10%, and the lower back musculature was elongated by about 50%. The results of this study showed that changes in back body surface caused by upper arm movements. It was influenced by the deltoid articulated with the humeri and the scapulae and trapezius. These body surface changes caused by muscle activities and ranges of motion can be used to design functional clothing.

• 한국안전학회지
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• 제30권3호
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• pp.93-99
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• 2015

Economic burden of work-related musculoskeletal disorder(WMDs) is increasing. Known causes of WMDs include improper posture, repetition, load, and temperature of workplace. Among them, improper postures play an important role. A smart sensor called SensorTag is employed to estimate the trunk postures including flexion-extension, lateral bend, and the trunk rotational speeds. Measuring gravitational acceleration vector in the smart sensor along the tri-orthogonal axes offers an orientation of the object with the smart sensor attached to. The smart sensor is light in weight and has small form factor, making it an ideal wearable sensor for body posture measurement. Measured data from the smart senor is wirelessly transferred for analysis to a smartphone which has enough computing power, data storage and internet-connectivity, removing need for additional hardware for data post-processing. Based on the estimated body postures, WMDs risks can be conviently gauged by using existing WMDs risk assesment methods such as OWAS, RULA, REBA, etc.

• Journal of Electrical Engineering and Technology
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• 제10권4호
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• pp.1910-1914
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• 2015

Human posture recognition is an attractive and challenging topic in computer vision due to its promising applications in the areas of personal health care, environmental awareness, human-computer-interaction and surveillance systems. Human posture recognition in video sequences consists of two stages: the first stage is training and evaluation and the second is deployment. In the first stage, the system is trained and evaluated using datasets of human postures to ‘teach’ the system to classify human postures for any future inputs. When the training and evaluation process is deemed satisfactory as measured by recognition rates, the trained system is then deployed to recognize human postures in any input video sequence. Different classifiers were used in the training such as Multilayer Perceptron Feedforward Neural networks, Self-Organizing Maps, Fuzzy C Means and K Means. Results show that supervised learning classifiers tend to perform better than unsupervised classifiers for the case of human posture recognition.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.147-150
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• 1996

Human posture prediction and motion simulation methods try to solve inverse kinematic problems using the optimization technique based on the concept of minimum principle. It is very important to select a cost function which relfects the human posture acurately. In this study, lifting postures were predicted using the five biomechanical cost functions and compared with real human postures in order to evaluate the predictivities of the cost functions. The result showed that all the biomechanical cost functions used in this study could not predict lifting postures accurately. The cost function which minimizes the sum of joint moments showed the smallest mean prediction error, while the one which minimizes the MUR showed statistically better performance.

• 대한가정학회지
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• 제44권4호
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• pp.159-173
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• 2006

The purpose of this study was to investigate the seating style of children between Korea and USA viewed from activity analysis in child-care centers. Observation and depth-interview method were used for data collection. Ninety-eight children aged from 38 to almost 62 months were observed for five minutes three times during an indoor free play period in Korea and USA in 2003 and 2004. The results of the research were as follows. There were significant differences between the postures of Korean and American children. Korean children maintained floor-seating postures longer than chair-seating and standing postures. The factors such as sex, age and physical environment influenced the children's seating style, while playing-type influenced their posture. This study will contribute to our understanding of the physical environment and children's seating style according to culture.

• 대한물리의학회지
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• 제1권1호
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• pp.37-47
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• 2006

Purpose : The purpose is to assess the effects of muscle activity of normal person with contact laterally wedged insoles with strapping of varying elevations of 9, 15, 21mm. Methods : The subjects were adult males and women who had not experienced any knee injury. They were asked to performed from isometric contraction exerciese in four postures using lateral wedged. The normalized EMG activity levels(%MVC) of the vastus lateralis, vastus medialis, tibialis anterior, soleus for the four postures of the lower extremities were compared using one way repeted measures ANOVA. Results : Comparison of EMG amplitudes across all postures revealed no significant differences among all muscles(P>0.05). Conclusion : Further studies of the effect of wedged insole angle on knee varus torque in patients with medial-lateral knee osteoarthritis are needed.

• 대한안전경영과학회지
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• 제17권4호
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• pp.223-229
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• 2015

In this study, We designed and implemented a assistant device for the standing X-ray views which is the one of the clinical X-ray imaging position. To evaluate the usability of the proposed assistant device, We choose 11 clinical patient postures that are used frequently and applied the postures to 5 volunteers. 11 images was taken from a volunteer for the patient postures. And we conducted a survey on safety and clinical usefulness, the 5 volunteers responded to the safety and 5 experts responded to the clinical usefulness. The survey results show that the volunteers feel more safe and the obtained images are very clear and clinically useful. The result for the image quality is 4.69 of 5(best) and safety is 2.84 of 3(best). It will be very profitable to both patients and hospitals by using the proposed assistant device.

• 대한인간공학회지
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• 제11권2호
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• pp.3-13
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• 1992

Resultant compressions on the L5/S1 joint of six subjects were studied as they lif- ted light weights in sitting and standing work postures. The subjects activities were photographed and analysed later by a static biomechamical computer model. Statistically significant differences were found between the result of the two postures analyses. Sitting posture showed significantly high compressions on the joint when doing several material handling tasks having the same work loads from the hip joint. Therefore, it is recommended that working with light weights in standing is less hazardous than doint the same work sitting postures, although both the maximum compression forces are under the Action Limit suggested by NIOSH.

• 산업공학
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• 제10권3호
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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.