• Journal of Korean Dental Hygiene Science
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• v.2 no.1
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• pp.19-30
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• 2019

To prevent the musculoskeletal diseases from repeated dental treatment, the health status and subjective symptom according to the working environment of dental hygienists were examined in 185 Gyeongnam dental hygienists from October 01, 2017 to October 30. The health status of the study subjects (χ²=40.21, p<.001), the physical burden of work (χ²=47.68, p<.001) and the mental fatigue of work (χ²=66.98, p<.001) were significantly different according to working experience. The level of mental fatigue depended on the number of dental hygienists in the clinics (p=0.032). 94.1% of the subjects knew musculoskeletal diseases and there were significant differences according to working experience (χ²=77.85, p<.001), the numbers of patients in a day (χ²=41.08, p<.001) and daily standing time (χ²=6.96, p=.008). Currently, 73.0% of the dental hygienists have musculoskeletal diseases. There was a significant difference according to the number of patients (χ²=51.01, p<.001) and daily standing time (χ²=25.15, p<.001). The presence of injured parts due to musculoskeletal disorders showed a significant difference according to the numbers of patients (χ²=18.98, p<.001) and daily standing hours (χ²=33.20, p<.001). The musculoskeletal diseases examination of dental hygienists is needed based on subjective symptoms of musculoskeletal diseases and prevention and management of measures musculoskeletal diseases are required.

• The Journal of Korea Robotics Society
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• v.12 no.3
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• pp.270-278
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• 2017

The electrical muscle stimulator (EMS) based human machine interface (HMI) free to mechanical constraint and muscle fatigue problems are proposed for force feedback in a virtual reality. The device was designed to provide force feedback up to 4.8 N and 2.6 N each to the thumb and forefingers. The main objective of the HMI is to make unnecessary mechanical structures to attach on the hand or fingers. It employs custom EMSs and an interface arranged in the forearm. In this work, major muscle groups such as extensor pollicis brevis (EPB), extensor indicis proprius (EIP), flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) are selected for efficient force feedback and controlled individually. For this, a human muscular-skeletal analysis was performed and verified. The validity of the proposed multi-channel EMS based HMI was evaluated thorough various experiments with ten human subjects, interacting with a virtual environment.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.2
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• pp.261-278
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• 1998

The paper represented the lower extremity muscle model as four rigid-body segments: trunk, shank, and foot. We transformed their tibial data into our shank data by rotating their tibial X and Y axes by 5.483 degrees, so the revised coordinate data used to translating the origin of their tibial reference frame to our shank reference frame. According to weight of subject, physiological cross-setional area(PCSA) of each lower extremity muscle was calculated by scaling those data by Brand. The objectives of this paper are to investigate the variations of the recruitment patterns of the lower extremity muscles, and to analyze the changes of the role assigned to each muscle during the seated foot operation. For exertion levels, the transition point of type F motor unit of each muscle is inferred by analyzing the electromyogram at the seated postures. Also, for predetermined seated foot operations exertion levels, the recruitment pattern and the changes of the role assigned are identified in the continuous exertion, by analyzing the electromyogram changes due to the accumulated muscle fatigue. This study can be used to design and to assess the pedals and foot-related equipments design.

• Journal of Yeungnam Medical Science
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• v.34 no.1
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• pp.101-105
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• 2017

Gitelman syndrome is a condition caused by a mutation of the thiazide sensitive Na-Cl cotransporter gene on the distal convoluted tubule. It results in a variety of clinical features, including hypokalemia, hypomagnesemia, hypocalciuria, and metabolic alkalosis. It is often diagnosed in asymptomatic adults presented with unexplained hypokalemia; however, it is sometimes associated with muscular cramps, numbness, fatigue, weakness, or paralysis. We experienced a case of rheumatoid arthritis accompanied by Gitelman syndrome, presented with hand tremor. We diagnosed her using renal clearance study and genetic analysis. Here, we report our experiences regarding this case along with a literature review.

• Journal of the Ergonomics Society of Korea
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• v.24 no.4
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• pp.23-30
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• 2005

The mailman's shoes should be designed in due consideration of occupational features they spend most of times to walk. For that reason, the shoes required functions to reduce the foot fatigue and to protect body by dispersing the body weight to the whole foot. In this research, for the functional improvement of the insole, insoles are investigated and analyzed by biomechanics experimentation. Under the base of these experimental results, we develop insoles that can reduce the body load and muscular-skeletal disorder. The pressures are concentrated on the metatarsus and heel by the result of analyzing pressure distributions of the using shoes. Accordingly, we offer the prototype functional insole that is ranked from high pressure to low pressure on the base of a shock absorb function. This prototype functional insole is examined for statistical significance by pressure distribution areas. The experimental results show that pressure areas are dispersed to whole foot, for this reason, pressures of the metatarsus and heel are reduced. Results of this research can not only improve the function of insoles which is suitable for occupational features, but also be a base on constructing data bases for biomechanics gait insoles.

• Korean Journal of Applied Biomechanics
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• v.20 no.3
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• pp.345-353
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• 2010

The purpose of this study was to compare and biomechanical evaluate the effects of three varying functional insoles on the kinematics of the lower extremities and foot pressure distribution during gait. For this 12 subjects participated in this study and each worn the 3 functional insoles during gait which kinematics, kinetics, electromyography and foot pressures were recorded. The function on the first insole was to absorb shock and increase the dynamic stability, the second was a gel type to absorb shock, and the third was to massage the center regions of the foot sole. the results were as follows; the first insole reduced the joints range of motion and reduced muscular fatigue, the second insole reduce the maximum, total and average foot pressures. Finally, the third insole produced larger values for the contact times and contact area.

• BMB Reports
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• v.47 no.2
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• pp.69-79
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• 2014

$Ca^{2+}$ release from intracellular stores and influx from extracellular reservoir regulate a wide range of physiological functions including muscle contraction and rhythmic heartbeat. One of the most ubiquitous pathways involved in controlled $Ca^{2+}$ influx into cells is store-operated $Ca^{2+}$ entry (SOCE), which is activated by the reduction of $Ca^{2+}$ concentration in the lumen of endoplasmic or sarcoplasmic reticulum (ER/SR). Although SOCE is pronounced in non-excitable cells, accumulating evidences highlight its presence and important roles in skeletal muscle and heart. Recent discovery of STIM proteins as ER/SR $Ca^{2+}$ sensors and Orai proteins as $Ca^{2+}$ channel pore forming unit expedited the mechanistic understanding of this pathway. This review focuses on current advances of SOCE components, regulation and physiologic and pathophysiologic roles in muscles. The specific property and the dysfunction of this pathway in muscle diseases, and new directions for future research in this rapidly growing field are discussed.

• The Journal of Korean Physical Therapy
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• v.12 no.1
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• pp.141-146
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• 2000

Making aged exercise by their age it unreasonable because there an differences of personal strength of their body. The three elements which control the aged's possibility of exercising effectivencess are the level of the physical strength in the present state, potential capacities of physical strength and age. Examined the physical strength of aged, the pliancy of body is considerably marked decline by and large and fast twitch muscle are withered. The reason why aged often do prime exercise like and infant. Aged are not fit for the speedy exercise and they can give full scope to their ability by continuing the long time exercise. The reason why aged should dwindle is mainly the retardation of recovering their fatigue which is related to the decline of oxygen activity. Anaerobic energy supply reduction makes aged be bad for severe physical exercise. Basal metabolic rate of rely on physical cellular quantity and people exercising has a high basal metabolic rate because of muscular amount. There were no decline of basal metabolic rate fellowing the age and physical non activiti influences on the atrophy of muscle.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.5 no.3
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• pp.152-157
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• 2012

In this paper, we develop a muscle exercise prescription system and present a prescription method by analyzing bioelectric signal of human muscles. This system is designed to give right exercise prescriptions include strength, duration, frequency of exercise after diagnosing personal body condition using EMG(Electromyography). With the help of these prescriptions all users can keep there optimum exercise status and avoid excess exercise symptom and, we van utilize in all the measurements like abnormal posture, muscle power, muscle regidity, muscle fatigue, muscle balance. Also easily accessable system can offer variable utilizations such as in health care center, sports center, social welfare center, social medical center, school, and kinder garden.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.465-472
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• 2022

Manual material handling is the one of the leading causes for musculoskeletal disorders (MSDs) and lower back discomfort. According to a study, construction formworkers suffer greater rates of muscular injuries and related illness due to manual activities. However, there is still a paucity of information on MSD, preventive posture issues, and corresponding solutions for construction aluminum formworkers. As a result, MSD and disregard of worker health and safety continue to exist at construction sites. Although preventive measures and strategies have been studied in previous research, we believe it is imperative to shed light on this problem through this study. This study aims to 1) implement a simple and cost-effective elevated bench to reduce MSDs, and 2) determine the rapid upper limbs assessment (RULA) and Ovako working posture analyzing system (OWAS) action catagory of workers in different postures to assess their MSD conditions and obtain an optimal position and posture using the Jack human modeling software and simulation tool. The study findings reveal a considerable reduction in MSD discomfort and which posture is acceptable in post-intervention instances.Thus results provide inexpensive and simple ergonomic interventions with favorable RULA and OWAS ratings that can be applied at construction sites. This study demonstrates workstation ergonomic intervention cases that can aid in understanding the urgency of applying existing research strategies into practice.