• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.3
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• pp.139-146
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• 2010

Recent studies suggest that prolonged standing at work is associated with varicose veins (VV). The objective of this study was to analyze the differences of VV risk in terms of work types in casino dealers and hotel service workers. Symptoms of VV were evaluated using a self-reported questionnaire from 2,092 participants, and muscle fatigue in the lower legs were evaluated using surface electromyography. The shift rate of median frequency in Gastrocnemius was -30.0% among the casino dealers working in prolonged static standing posture, and - 14.3% among the casino dealers sitting during working time. After adjusting age, gender, smoking, and family history of VV, the risk ratio of VV was 3.67(95% CI 2.03-6.59) in group I (prolonged standing and occasional walking at work), 6.29(95% CI 3.48-11.35) in group II (prolonged standing, occasional walking and heavy lifting at work), and 8.07(95% CI 4.51-14.43) in groupIII(prolonged static standing at work). In conclusion, prolonged standing at work may be a work related risk factor of VV.

• Exercise Science
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• v.26 no.1
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• pp.61-68
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• 2017

PURPOSE: To examine the cumulative (7 days) effect of breaking up prolonged sitting on systemic endothelial function in sedentary men. METHODS: Thirty sedentary men ($33.93{\pm}5.72years$) participated in two randomized 7 days sitting trial (Sit group (control) vs. Breaks group). The protocol of Breaks group is as follows: 4-minute of moderate-intensity marching in place (walking) every 1 hour during business hour (total: 8 breaks/day). Assessment of brachial artery endothelial function using flow-mediated dilation (FMD) and arterial stiffness indices (augmentation index, arterial pressure and pulse wave velocity) were measured before and after 7 days treatment. RESULTS: Brachial artery FMD significantly increased after 7 days breaking up prolonged sitting treatment (Breaks groups, $9.65{\pm}2.61$ to $9.62{\pm}2.6%$) compared with 7 days prolonged sitting (Sit group, $8.37{\pm}3.41$ to $10.11{\pm}3.75%$) (interaction effect, p=.004). Arterial pressure (AP) significantly increased after treatment (Breaks group, $2.75{\pm}2.19$ to $2.38{\pm}1.63mmHg$, p=.002) in Sit group but there was no change (Sit group, $1.00{\pm}3.18$ to $2.50{\pm}9.23mmHg$) in Breaks groups (interaction effect, p=.008). CONCLUSIONS: These finding show that 7 days regular breaking up prolonged sitting improve in FMD, compared with prolonged sitting. Therefore, regular breaking up prolonged sitting may improve systemic endothelial function in sedentary men.

• Korean Journal of Applied Biomechanics
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• v.26 no.1
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• pp.135-142
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• 2016

Objective: The purpose of this study was to investigate the acute effect of walking on high heels on the behavior of fascicle length and activation of the lower limb muscles. Methods: Twelve healthy inexperienced high heel wearers (age: $23.1{\pm}2.0yr$, height: $162.4{\pm}4.9cm$, weight: $54.4{\pm}8.5kg$) participated in this study. They walked in high heels (7 cm) and barefoot on a treadmill at their preferred speed. During the gait analysis, the lower limb joint kinematics were obtained using a motion analysis system. In addition, the changes in fascicle length and the level of activation of the medial gastrocnemius (MG) were simultaneously monitored using a real-time ultrasound imaging technique and surface electromyography, respectively. Results: The results of this study show that the MG fascicle operates at a significantly shorter length in high heel walking ($37.64{\pm}8.59mm$ to $43.99{\pm}8.66mm$) in comparison with barefoot walking ($48.26{\pm}9.02mm$ to $53.99{\pm}8.54mm$) (p < .05). In addition, the MG fascicle underwent lengthening during high heel walking with relatively low muscle activation while it remained isometric during barefoot walking with relatively high muscle activation. Conclusion: Wearing high heels alters the operating range of the MG fascicle length and the pattern of muscle activation, suggesting that prolonged wearing of high heels might induce structural alterations of the MG that, in turn, hinder normal functioning of the MG muscle during walking.

• Journal of the Ergonomics Society of Korea
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• v.27 no.3
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• pp.71-79
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• 2008

Walking shoes for walking and jogging have been used to enjoy lots of leisure time. Functional shoes such as walking shoes have special functions to improve body motility by changing of shoe shapes. The walking shoes could improve the motility by structural transformation of outsole as increase degrees of heel and toe. The study on insoles has not been conducted enough on the contrary of the study of outsole. The purpose of this study is to perform ergonomics analysis whether the Arch Supported insoles have an improving effect of muscle activities or not. Experiments were performed with 6 subjects who are health and haven't experienced any diseases past. EMG(Electromyography) and Foot Pressures were measured repeatedly for 5 seconds at 0 hour, after 1 hour and after 2 hours of walking. Insoles used for experiment are normal insole, insole inserted Arch Support and pad. The electrodes for EMG measurement were set on waist (erector spinae), and thigh (vastus lateralis), calf (gastrocnemius). Evaluations of EMG were analyzed by shift of MF (Median Frequency) and MPF (Mean Power Frequency). Foot Pressure was analyzed by mean pressure of feet and change of walking time. As results, Arch Support insole had larger frequency shift value than that of normal insole. Frequency shift between Arch Support insoles and normal insole showed significant difference on 95% confidence interval. And insole 1 has the highest value of frequency shift. For results of foot pressure, Arch Support insoles show continuous decreasing tendency when comparing with normal insoles by changing of times. Also, insole 1 has the highest decreasing value of foot pressure. Therefore, this study presented that the Arch Support insole can promote muscle activities and improves comfort for a prolonged walking.

• International Journal of Control, Automation, and Systems
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• v.3 no.2
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• pp.152-158
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• 2005

Commercial lower limb prostheses or orthotics help patients achieve a normal life. However, patients who use such aids need prolonged training to achieve a normal gait, and their fatigability increases. To improve patient comfort, this study proposed a method of predicting gait angle using neural networks and EMG signals. Experimental results using our method show that the absolute average error of the estimated gait angles is $0.25^{\circ}$. This performance data used reference input from a controller for the lower limb orthotic or prosthesis controllers while the patients were walking.

• Journal of Korean Neurosurgical Society
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• v.53 no.5
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• pp.269-273
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• 2013

Objective : Posture induced common peroneal nerve (CPN) palsy is usually produced during the prolonged squatting or habitual leg crossing while seated, especially in Asian culture and is manifested by the onset of foot drop. Because of its similarity to discogenic foot drop, patients may be diagnosed with a lumbar disc disorder, and in some patients, surgeons may perform unnecessary examinations and even spine surgery. The purpose of our study is to establish the clinical characteristics and diagnostic assessment of posture induced CPN palsy. Methods : From June 2008 to June 2012, a retrospective study was performed on 26 patients diagnosed with peroneal nerve palsy in neurophysiologic study among patients experiencing foot drop after maintaining a certain posture for a long time. Results : The inducing postures were squatting (14 patients), sitting cross-legged (6 patients), lying down (4 patients), walking and driving. The mean prolonged neural injury time was 124.2 minutes. The most common clinical presentation was foot drop and the most affected sensory area was dorsum of the foot with tingling sensation (14 patients), numbness (8 patients), and burning sensation (4 patients). The clinical improvement began after a mean 6 weeks, which is not related to neural injury times. Electrophysiology evaluation was performed after 2 weeks later and showed delayed CPN nerve conduction study (NCS) in 24 patients and deep peroneal nerve in 2 patients. Conclusion : We suggest that an awareness of these clinical characteristics and diagnostic assessment methods may help clinicians make a diagnosis of posture induced CPN palsy and preclude unnecessary studies or inappropriate treatment in foot drop patients.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.341-347
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• 2003

Smith-Magenis syndrome (SMS) is a clinically recognizable multiple congenital anomaly and mental retardation syndrome caused by an interstitial deletion of chromosome 17 p11.2. Physical features include short stature, characteristic facial appearance: flattened mid-face, down-turned mouth, prominent and often rosy cheeks; prominent jaw in older children and adults, chronic ear infections, hearing impairment, eye problems, including: strabismus (an eye which turns in or out) and myopia (nearsightedness), hoarse voice, short fingers and toes, heart defects or murmurs, problems related to the urinary system, scoliosis (curvature of the spine), an unusual gait (walking pattern), and decreased sensitivity to pain. Behavioral and developmental characteristics include speech delay and articulation problems, developmental delay, learning disability, mental retardation, hyperactivity, self-injury, including: head banging; hand biting; picking at skin, sores and nails; pulling off finger- and toenails; inserting foreign objects into ears, nose, or other body orifices, explosive outbursts, prolonged tantrums, destructive and aggressive behavior, excitability, arm hugging or hand squeezing when excited. This report is the case of a Korean 3-year-3-month old male with Smith-Magenis syndrome referred from local clinic for the treatment of dental caries. The patient was treated by physical restraint after prophylatic administration of antibiotic(Amoxacillin 50mg/kg).

• Journal of Life Science
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• v.20 no.1
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• pp.71-76
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• 2010

The purpose of this study was to investigate the changes of long term ECG response in a company with middle-aged male employees. Subjects were 60 men who were 40~55 years old. We enrolled 30 exercise group subjects into a 3-year exercise program. In measurement index, body composition was measured by % body fat and BMI. Exercise stress test analyses were measured using ST/HR slope and QRS vector. Statistical analysis was performed using analysis of repeated ANOVA. Results of this study were as follows: In ST/HR slope, the control group showed symptoms of ischemia after nine minutes of exercise. In the rest frontal axis of the QRS vector, the control group had a tendency towards right axis deviation. In the rest horizontal amplitude of the QRS vector, the control group had a tendency to show a significant decrease, but it was increased significantly in the exercise group. These findings suggest that inactive company workers was showed a decrease of exercise capacity, early diagnosis exercise-induced ST depression, and prolonged deviation of QRS vector, but that cardiac function could be elevated in active middle aged men through regular exercise program participation.

• Journal of Intelligence and Information Systems
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• v.29 no.1
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• pp.307-325
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• 2023

Due to the prolonged COVID-19 pandemic, the frequency of people who are tired of living indoors visiting nearby mountains and national parks to relieve depression and lethargy has exploded. There is a place where thousands of people who came out of nature stop walking and breathe and rest, that is the mineral spring. Even in mountains or national parks, there are about 600 mineral springs that can be found occasionally in neighboring parks or trails in the metropolitan area. However, due to irregular and manual water quality tests, people drink mineral water without knowing the test results in real time. Therefore, in this study, we intend to develop a model that can predict the quality of the spring water in real time by exploring the factors affecting the quality of the spring water and collecting data scattered in various places. After limiting the regions to Seoul and Gyeonggi-do due to the limitations of data collection, we obtained data on water quality tests from 2015 to 2020 for about 300 mineral springs in 18 cities where data management is well performed. A total of 10 factors were finally selected after two rounds of review among various factors that are considered to affect the suitability of the mineral spring water quality. Using AutoML, an automated machine learning technology that has recently been attracting attention, we derived the top 5 models based on prediction performance among about 20 machine learning methods. Among them, the catboost model has the highest performance with a prediction classification accuracy of 75.26%. In addition, as a result of examining the absolute influence of the variables used in the analysis through the SHAP method on the prediction, the most important factor was whether or not a water quality test was judged nonconforming in the previous water quality test. It was confirmed that the temperature on the day of the inspection and the altitude of the mineral spring had an influence on whether the water quality was unsuitable.