• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.11
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• pp.1131-1137
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• 2017

Recently, regulations on fuel efficiency and $CO_2$ emissions have been reinforced in automobile industries. As a result, many companies make an effort to satisfy these regulations by adapting composite materials to the automobile body as well as its components. In particular, the lower control arm in the suspension system is subjected to heavy loads and is designed to be thick to meet operating loads. Therefore, it is essential for the lower control arm to reduce weight and to secure the durability assessment. In this paper, we conducted structural analysis by performing stress and stiffness analysis under given load conditions through finite element analysis, and verified whether it satisfies the load and stiffness conditions. The inertia relief method is adapted to the process of analysis, and the principal stress is used as a criterion for evaluation. Based on these results, the durability assessment is carried out using the stress-life method.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.4
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• pp.482-489
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• 2011

In practical design process, designer needs to find an optimal solution by using full factorial discrete combination, rather than by using optimization algorithm considering continuous design variables. So, ANOVA(Analysis of Variance) based on an orthogonal array, i.e. Taguchi method, has been widely used in most parts of industry area. However, the Taguchi method is limited for the shape optimization by using CAE, because the multi-level and multi-objective optimization can't be carried out simultaneously. In this study, a combined method was proposed taking into account of multi-level computational orthogonal array and TOPSIS(Technique for Order preference by Similarity to Ideal Solution), which is known as a classical method of multiple attribute decision making and enables to solve various decision making or selection problems in an aspect of multi-objective optimization. The proposed method was applied to a case study of the multi-level shape optimization of lower arm used to automobile parts, and the design space was explored via an efficient application of the related CAE tools. The multi-level shape optimization was performed sequentially by applying both of the neural network model generated from seven-level four-factor computational orthogonal array and the TOPSIS. The weight and maximum stress of the lower arm, as the objective functions for the multi-level shape optimization, showed an improvement of 0.07% and 17.89%, respectively. In addition, the number of CAE carried out for the shape optimization was only 55 times in comparison to full factorial method necessary to 2,401 times.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.10
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• pp.1323-1328
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• 2011

In the current design process for the lower arm used in automobile parts, an optimal solution of its various design variables should be found through exploration of the design space approximated using the response surface model formulated with a first- or second-order polynomial equation. In this study, a multi-level computational DOE (design of experiment) was carried out to explore the design space showing nonlinear behavior, in terms of factors such as the total weight and applied stress of the lower arm, where a fractional-factorial orthogonal array based on the artificial neural network model was introduced. In addition, the tolerance robustness of the optimal solution was estimated using a tolerance optimization with six sigma constraints, taking into account the tolerances occurring in the design variables.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.613-618
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• 2020

The average dose of Fast Low Dose C-arm CT used during hepatic arterial chemoembolization was compared with the average dose of DSA, and the exposure dose was analyzed by analyzing the average dose for each test technique in the total accumulated dose. 50 patients were randomly selected at our clinic and compared with Fast Low Dose C-arm CT, DAP and Air Kerma of DSA, and the accumulation of four test techniques (DSA, Fast Low Dose C-arm CT, Roadmap, Fluoroscopy) The proportion of dose (DAP, Air Kerma) was analyzed. For statistical comparative analysis, the corresponding sample T test and ANOVA test (post hoc test: Tukey) were performed using the statistical program SPSS 20.0. Fast Low Dose C-arm CT showed statistically significantly lower average dose (DAP, Air Kerma) than DSA. Reducing the number of tests for DSA can reduce the patient's exposure to medical radiation.

• The Journal of Korean Physical Therapy
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• v.34 no.4
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• pp.149-154
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• 2022

Purpose: The purpose of this study was to investigate effects of the modified bent arm tornado exercise on weight shift movement and muscle activity of the impact section in the top of the drive swing. Methods: Twenty subjects were divided professional golfer group and amateur golf group. Subjects were required to complete following modified bent arm tornado exercise. The activity and weight shift of the gluteus group and lower extremity muscles between the two groups were measured and the Wilcoxon rank test was analyzed. Results: The distribution of weight shift in the professional golfer group was higher than that of the amateur golfer group (p<0.05). During the golf downswing of the professional golfer group, muscle activation of the lower extremities was higher than that of the amateur golfer group (p<0.05). The distribution of weight shift after exercise by the amateur golfer group was higher than before (p<0.05). Conclusion: We could confirm was increased significantly of muscle activity and weight shift by applying modified bent arm tornado exercise through this study. This result suggests that exercise is needed to improve weight shift.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.6
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• pp.911-923
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• 1995

The zone of expansion and contraction of arm surfaces was analyzed, the correlation between arm surface changes was studied, and ergonomic sleeve designs were presented in which the consideration of body surface changes is emphasized. Experiments were carried out which include 43 upper extremity segments, 21 motions and 35 female subjects. The major conclusions of the study are as follows : 1. As a sleeve drafting method, detailed measures should be applied on the base of the sensitivity of body surface changes. The range of arm surface changes can be divided into three zones : concentrated expansion zone, zone of little change, and contraction part. The maximum expansion zone was the upper part of elbow. 2. The correlations were higher in lengths than in circumferences. Arm lengths were mainly correlated with upper arms. The more detailed the arm surface was, the lower the correlations between surface changes were. So there was not a lot of relation between segment changes. Tendency of body surface changes depended on the anatomical structure of the upper extremity and the movements of arm muscles. 3. As an application of measures and ease, ergonomic sleeve designs weve presented in which arm surface changes were considered. Ergonomic sleeve designs are recommended for working clothes and sports wear.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2009.03a
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• pp.160-160
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• 2009

Compartment syndrome is not uncommon in the forearm or lower extremity, but it is relatively rare in the upper arm. This rarity might delay the diagnosis, especially in the unconscious or intoxicated patient. Therefore, a high index of suspicion is needed to make an accurate, early diagnosis. Although excessive muscle strain leading to localized compartment syndrome is seldom encountered in the upper arm, three cases of compartment syndrome in the upper arm after blunt injury have been reported. Interestingly, there were no bony injuries in any of these patients. However, there are only two reports of isolated dorsal compartment syndrome after blunt trauma. The present report presents the case of a patient who had blunt trauma to the upper arm that resulted in the development of compartment syndrome in the isolated dorsal compartment of the upper arm.

• Journal of the Korean Society of Costume
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• v.30
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• pp.201-210
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• 1996

The perpose of this study is to compare and to analyze the characters of the shape of up-per arm and armscye line between young and aged women. The subjects were measured with the Mar-tin's anthropometer and with free curve ruler. 10 items in the shape of upper arm were measured and 16 items in the shape of armscye line measured indirectly based on the measured shape taken from the subjects with free curve ruler and both date were analyzed. Mean standard deviation f-test factor analysis were performed for the statistical analysis of the date. The main results were as follows: 1) The shape of the upper arm is long and narrow in youg women compared with aged. 2) The length of the axilla of the aged women were longer than that of young women. 3) There are significant differences young and aged women on the shape of armscye line. THe length of from the front point of axilla to shoulder point width and depth of the shape of the armscye line length of axilla of aged women were longer than that of young. but the length of from the back point of axilla to shoulder point of yyoung women was longer than aged. 4.) The front point of axilla was existed lower than back point of axilla in aged women while front point of axilla was existed higher than the back point in young. 5) Through the factor analysis two factors were obtained from the shape of the upper arm and five factors from the shape on armmscye line in both groups. Factor compornents in the shape of the up per arm were length width and girth of that and in the shape of the armscye line were width and length of upper and lower back and front part of the shape of the armscye line depth of the axilla. he items in the same factor were resemble each other between two groups.

• Archives of Reconstructive Microsurgery
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• v.13 no.1
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• pp.51-57
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• 2004

Introduction: To cover the exposed tendons and bones in the foot and hand which need coverage and abundant vascular flow, lateral arm flaps were transferred. Lateral arm flap is a thin and innervated fasciocutaneous flap with a lower lateral cutaneous nerve and posterior radial collateral artery. Materials and methods: From October 1992 through September 2003, we have performed 5 lateral arm flaps for reconstruction of the exposed achilles tendons in 2 cases and the exposed forearm extensors, 2nd to 5th metacarpal bones and scaphoid each 1 case. The causes were traffic accident in 2 cases and machinary injury in 3 cases. Age range was between 31 to 74 (average 50) and all male except 1. Posterior lateral collateral artery and venae comitantes were anastomosed by end to end in 3 cases and vena comitante in 2 cases. Lower lateral cutaneous nerve was anastomosed with a branch of superficial radial nerve in 2 cases. Results: The results were evaluated by survival of the flap, sensory discrimination, cosmesis and comfort in the activities of the daily living. All flaps were survived. Sensory recovery was graded as deep cutaneous pain sensibility in 2 cases. Cosmesis was moderately satisfied and comfort was good except 1 as moderate. Postoperative defatting procedure was done in 1 case and skin abrasion was occurred in 1 case. Conclusion: Lateral arm flap was suitable for coverage of the exposed achilles tendons and exposed forearm extensors, metacarpals and scaphoid in the wrist.

• The Journal of Korean Physical Therapy
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• v.31 no.3
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• pp.151-156
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• 2019

Purpose: This study aimed to investigate the immediate effects of posture correction and real-time visual feedback using a video display on muscle activity and change of head position during overhead arm lift test in individuals with forward head posture. Methods: Fifteen subjects with forward head posture and fifteen normal subjects who volunteered were included in this study. During both groups performed the overhead arm lift test, the muscle activity of the upper trapezius, serratus anterior, sternocleidomastoid, and lower trapezius muscle were measured using electromyography, and head position change was measured using photographs. Then, forward head posture group was asked to perform overhead arm lift test again after posture correction and real-time visual feedback using a video display respectively. One-way analysis of variance (ANOVA) was used to analyze four conditions: pre-test, posture correction, real-time visual feedback, and the control group. Results: The upper trapezius and lower trapezius muscle activity significantly decreased posture correction, real-time visual feedback, and control group than pre-test of forward head posture group (p<0.05). The sternocleidomastoid muscle significantly decreased real-time visual feedback and control group than pre-test of forward head posture group. Head position change significantly decreased three conditions than pre-test of forward head posture group and real-time visual feedback and control group significantly decreased than posture correction. Conclusion: This study recommend for maintaining cervical stability during the overhead arm lift test, postural control using real-time visual feedback is more effective in subjects with forward head posture.