• Journal of agricultural medicine and community health
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• v.16 no.1
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• pp.40-47
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• 1991

Musculoskeletal disorders are a major cause of occupational disabilities. Approximately thirty percent state that the major reason for an inability to work is a musculoskeletal problem. A farm work is associated with increased stress and trauma to joints. Chronic overuse injuries are a result of stresses that exceed the body's adaptive or healing capabilities. They can occur in bone, tendons and muscle-tendon-bone junctions. The aim of the investigation was to the study the frequency of pain, ache, and discomfort in the musculoskeletal system among farmers, to find possible correlations between these symptoms and various working positions and different working actions. A questionnaire was answered by 138 farmers. Of those who answered the questionnaire 82% had pain and discomfort from back, shoulders, arms in orders, The result showed that musculoskeletal pain predominate in the farming seasons, and of those who had pain and discomfort 89% thought that farm works had a correlation with the pain and discomfort of musculoskeletal system. But only 17% of quationnaire were put to periodic medical examinations, and 50% of those who had pain and discomfort consulted a doctor. Education in effective pain treatment should therefore be intensifide to ascertain that farmers in rural areas have satisfactory knowledge of the musculoskeletal pain as a chronic overuse syndrome.

• Transactions on Electrical and Electronic Materials
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• v.18 no.5
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• pp.298-302
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• 2017

With an increasing aging population and improved standards of living, more attention has been paid to health. Although walking exercise is known as an aerobic exercise, it imposes repeated and continuous impacts on the joints of the lower extremities. Therefore, when overweight gives a burden to the lower extremity or there is a joint disease, exercise limit occurs. The articular cartilage, weakened with age, also makes it difficult for the elderly to perform walking exercises. Accordingly, this study conducted a comparative analysis between regular walking using only the lower extremity and Nordic walking, which has been known as stable. For analysis, electromyography (EMG) was performed and the ground reaction force of the upper and lower extremities were measured in the same exercise. Integrated EMG (iEMG) revealed that the upper extremity muscles were more active in Nordic walking than in regular walking, where lower extremity muscles were relatively more inactive. In addition, when EMG measurements were performed at each measurement point during walking exercise, the pattern was different. Nevertheless, the result was the same as in iEMG. The load that occurs in each exercise was measured using the ground reaction force system. As a result, Nordic walking had a lower load than regular walking. Therefore, it was found that Nordic walking minimized the load on the lower extremities owing to the effect of whole-body exercise and was a safer and more efficient exercise method.

• Journal of KSNVE
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• v.9 no.6
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• pp.1259-1266
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• 1999

The objective of this investigation is to develop a compliant track link model and apply this model to the multi-body dynamic analysis of high mobility tracked vehicles. Two major difficulties encountered in developing the compliant track models. The first one is that the integration step size must be kept small in order to maintain the numerical stability of the solution. This solution deals with high oscillatory signals resulting from the impulsive contact forces and stiff compliant elements to represent the joints between the track links. The second difficulty is due to the large number of the system equations of motion of the three dimensional multibody tracked vehicle model. This problem was sloved by decoupling the equations of motion of the chassis subsystem and the track subsystems. Recursive methods are used to obtain a minimum set of equations for the chassis subsystem. Several simulation scenarios were tested for the high mobility tracked vehicle including accelaeration, high speed cruising, braking, and turning motion in order to demonstrate the effectiveness and validity of the methods proposed in this investigation.

• Fashion & Textile Research Journal
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• v.14 no.1
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• pp.136-143
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• 2012

The purpose of this study was to investigate the influence of physical functions of elderly people on their clothing behavior and to provide basic information about manufacturing comfortable apparels for the elderly. A total of 219 people, with ages between 60s and 70s, participated in the survey and in the experiment to correlate their tendency of wearing clothes with the state of their physical functions. About 78.5% of the elderly showed eyesight deterioration in the subjective evaluation. Elders in their 60s raised their arms higher up in overhead reach, and showed shorter distance between middle fingertips in behind back stretch and in back scratch than elders in their 70s. Also, the former stretched farther to the floor in standing trunk flexion, and maintained more steady in one leg stand and in tandem stance than the latter. The narrower the movement range of the upper limb joints was, the more the elderly preferred upper garments with full front opening to those with half or no opening. The more inflexible the upper limbs and waist and the more unbalanced the body was, the more likely the elderly put on pants while sitting on the floor. The time taken to button up the shirt and to put on and take off pants showed a positive correlation with the overhead reach, the behind back stretch, the back scratch and the standing trunk flexion, whereas the former showed a negative correlation with the one leg stand and the tandem stance.

• Korean Journal of Applied Biomechanics
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• v.26 no.1
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• pp.71-82
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• 2016

Objective: The purpose of this study was to investigate kinematic comparisons of Tsukahara vault in gymnastics between a top-level athlete and sublevel collegiate athletes in order to obtain information on key biomechanical points for successful Tsukahara vaults. Methods: An Olympic gold medalist (height, 160 cm; weight, 52 kg; age, 25 years) and five sublevel collegiate gymnasts (height, $168.2{\pm}3.4cm$; weight, $59.6{\pm}3.1kg$; age, $23.2{\pm}1.6years$) participated in this study. They repeatedly performed Tsukahara vaults including one somersault. Fourteen motion-capturing cameras were used to collect the trajectories of 26 body markers during Tsukahara vaults. Event time, displacement and velocity of the center of mass, joint angles, the distance between the two hands on the horse, and averaged horizontal and vertical impact forces were calculated and compared. Results: The top-level athlete showed a larger range of motion (ROM) of the hip and knee joints compared to sublevel collegiate athletes during board contact. During horse contact, the top-level athlete had a narrow distance between the two hands with extended elbows and shoulders in order to produce a strong blocking force from the horse with a shorter contact time. At the moment of horse take-off, reactive hip extension of the top-level athlete enhanced propulsive take-off velocity and hip posture during post-flight phase. Conclusion: Even though a high velocity of the center of mass is important, the posture and interactive action during horse contact is crucial to post-flight performance and the advanced performance of Tsukahara vaults.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.7
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• pp.745-750
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• 2012

This study extends the constraint force design method allowing topology optimization for planar rigid-link and string mechanisms. To our best knowledge, by applying conventional machine and mechanism design theories, it is likely that it is possible to find out optimal locations of joints and lengths of rigid-links but somewhat difficult to find out optimal topology of rigid-links. To achieve optimal topology of rigid links, there is our previous contribution so called the new constraint force design method with the binary design variables determining the existence of the auxiliary forces imposing apparent lengths among unit masses. By adding new binary design variables, this research extends the constraint force design method to find out optimal mechanism consisting of stringy links as well as rigid links that seems impossible in the conventional machine and mechanism design theories.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.2
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• pp.87-100
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• 2011

Objectives : This study was carried out to investigate the effects of Buja-tang treatment on the early change of the monosodium iodoacetate-induced osteoarthritis in rats. Methods : Arthritis was induced by injection of monosodium iodoacetate(MIA)(0.25 mg) into both knee joint cavities of rats. Arthritic rats were divided into control(n=8) and treated(n=8) group. The control group was taken distilled water and the treated group, extracts of Buja-tang by orally for 20 days. At the end of the experiment(20 days after MIA injection), gross and histopathological examinations on the articular structures of knee joints were performed. Proteoglycan(PG) content in articular cartilages was analyzed by safranine O staining method. And also, tumor necrosis factor-$\alpha$($TNF-{\alpha}$) and interleukin-$1{\beta}$($IL-1{\beta}$) contents in synovial fluid were measured by enzyme-linked immunosorbent assay(ELISA) method. Results : 1. Body weight(g) of the treated group was increased significantly compared with control group at 15 and 20 days after injection. 2. Grossly, the degree of osteoarthritis in the treated group was alleviated compared with the control group. 3. PG content in articular cartilage of the treated group was increased significantly compared with the control group. 4. Histopathologically, osteoarthritic score of the treated group was decreased significantly compared with the control group. 5. $TNF-{\alpha}$ content in synovial fluid of the treated group was decreased significantly compared with the control group. Conclusions : On the basis of these results, we suggest that Buja-tang have inhibiting effects on the progression of arthritis in MIA-induced osteoarthritis model. And it is related to inhibiting the activity of $TNF-{\alpha}$ in osteoarthritic chodrocytes and synovial membranes.

• Korean Journal of Applied Biomechanics
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• v.17 no.1
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• pp.111-119
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• 2007

The purpose of this study was to investigate muscle activity and gait pattern in lower limb depending on the outsole of heel rockers. Fifteen healthy men volunteered for this experiment. Each subject performed totally three trails with two pairs of different heel rocker shoes and a pair of normal running shoes at speed of 1.33m/s for 1 minute during walking on a treadmill. Kinematic data gathered in 100Hz was recorded and analyzed by using the 3D motion capture system to measure the trunk tilt and joint angle of the right lower limb. And the lower extremity muscle activities were simultaneously recorded in 1000Hz and assessed by using EMG. The statistical analysis was the one-way ANOVA with the repeated measures to compare among the three kinds of shoes. The level of statistical significance for all tests was 0.05. Joint angle of lower limb was showed statistically significant different in MST(hip joint), LHS(ankle joint), and RTO(knee and ankle joint). Muscle activity of rectus femoris and biceps femoris was statistically increased in both heel rocker shoes during gait cycle on treadmill. The maximum peak time of tibialis anterior in the negative heel rocker showed the delay of approximately 23.8%time than normal shoes. Gait pattern variability of the negative heel rocker was increased in the first half of the stance phase and the variability of the positive heel rocker was increased in the terminal stance phase. In Conclusion, stability was decreased in between joints of lower limb on positive heel rocker than negative heel rocker. This study found that there were different joint angle, muscle activity, gait pattern and coordinate system of the lower limb in each kind of shoes. These unstability affected the lower extremity and the whole body. A further study has to be continued with study of rehabilitation and exercise for a long-term.

• The Journal of the Korea Contents Association
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• v.14 no.9
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• pp.1-13
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• 2014

Apart from the physical realism, the implementation of various physical actions of an agent to respond to dynamically changing situations is essential for the design of an agent in a cyber world. To achieve a maximum diversity in actions, we develop a mechanism that allows composite actions to be constructed by reusing a set of primitive motions and enables an agent to instantly react to changes in the ambient states. Specifically we model an agent's body in terms of joints, and a primitive or composite motion is performed in a real time. To implement this mechanism, we produce an animation for basic joint movements and develop a method to construct overall motions out of the primitive motions. These motions can be assembled into a plan by which an agent can achieve a goal. In this manner, diverse actions can be implemented without excessive efforts. This approach has conspicuous advantages when constructing a parallel action, e.g., eating while walking, that is, two or more parallel actions can be naturally merged into a parallel action according to their priority. We implement several composite and parallel actions to demonstrate the viability of our approach.

• Journal of Haehwa Medicine
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• v.14 no.1
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• pp.141-147
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• 2005

The most fundamental and important medical treatment is science of acupuncture and moxibution, which is based on twelve channels theory. Meridian is a pathway that conveys material and energy in a human body. Twelve channels are divided into channels of hand & foot, channels of yin & yang. Yang channels are divided into taiyang, yangming, shaoyang, yin channels are divided into taiyin, shaoyin, jueyin. These are referred to twelve channels, and this theory is being used for diagnosis and test in oriental medicine. Meridian-doin-tajiquan is born, combining taijiquan which is recently handed down from China and Korean traditional method for health protection and treatment in ancient times and twelve channels, three yin & yang theory. I report this because meridian-doin-tajiquan which is non-medical and non-invasive way can be used in the treatment of disease, just like three yin & yang theory, the heart of the meridian theory, and Gehapchu theory are adjusted in the clinical science of acupuncture and moxibution. And I report this because I could mater the appropriateness of the traditional theory and I believed this corresponded with it, training myself by meridian-din-tajiquan. It is considered that this will be used in the treatment of pain disease of muscles and joints system and the diabetes, hypertension, obesity caused by stress in the near future.