• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.433-437
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• 2009

The purpose of this study was to measure circumference of four body parts of each Sasang groups with Bioelectrical Impedance Analysis (BIA), and evaluate its usefulness for Sasang type diagnostic test. We obtained the circumference measures of neck (CN), chest (CC), waist (CW), and hip (CH) of 91 college students using BIA and standardized by sex and age. The validity of Sasang group prediction with CC was evaluated. The Tae-Eum group (104.87${\pm}$5.19, 108.47${\pm}$4.96, 116.00${\pm}$9.39, 110.4${\pm}$5.29. neck, chest, waist and hip, respectively) has significantly (p<0.001) bigger circumferences than So-Yang (97.79${\pm}$3.82, 100.02${\pm}$4.21, 101.02${\pm}$7.88, 101.95${\pm}$4.06) and So-Eum (95.63${\pm}$4.67, 96.93${\pm}$4.80, 97.63${\pm}$7.72, 99.86${\pm}$4.40) groups at very four measures. Discriminant functions with CC can be used for Tae-Eum Sasang type diagnostic test with 91.2% of overall Percentage Correctly Predicted (PCP). Tae-Eum type-specific sensitivity was 73.3% and Tae-Eum type-specific specificity was 94.7%. The strength and weakness of measurement and standardization methods for Sasang type diagnostic test, and the methods for the standardization of physical traits with sex and age were discussed. Our study showed distinctive physical features of Tae-Eum type and the usefulness of BIA for the Sasang type diagnosis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1180-1190
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• 2013

This study is to analyze femoral necks and lumbar spine bone mineral density in Korean men aged 60 or older 2,736 people, as well as to research in its relation to anthropometry, life style, diet, fracture history, family history of osteoporosis and medical history using data from Korea National Health and Nutrition Examination Survey (KNHANES)(the 2nd(2008) and 3rd(2009) year at the 1st survey, and the 1st(2010) year at the 5th survey). To express the strength of the associations, percent differences were calculated from multiple linear regression models using the formula ${\beta}{\times}$(unit/mesnBMD). Unit for continuous variables were chosen to approximate 1 standard deviation(SD). Prevalence of osteoporosis for 60-69, 70-79 and >80 old men were 6.7%, 15.8% and 31.4% respectively. The proportion of osteoporosis calculated for each age group in the femoral neck group was: 60-69 years old, 2.6%, 70-79years old, 8.2%, >80years old, 24.8%. For the lumbar spine group, the values were: 60-69 years old, 5.5%, 70-79years old, 11.3%, >80years old, 15.4%. In men aged 60 or older, lean mass greatly influenced bone density in the femoral neck and lumbar spine. Thus, to increase the lean mass would be an effective way to prevent osteoporosis in elderly men.

• Physical Therapy Korea
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• v.13 no.3
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• pp.92-101
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• 2006

The purpose of this study was to investigate the characteristics and the current condition of musculoskeletal pain sufferers among fitness center users. The investigation used self-reporting questionnaire with the 797 subjects. On average, the subjects were 30.6 years old, 168.8 cm in height and 65.2 kg in weight. Among them, 423 were male (53.1%) and 374 were female (46.9%). Out of them, 276 suffered from pain, (35.2%). More men felt muscle aches than women (p<.05). In terms of pain, lower back area topped the list with 44.9%, followed by the lower extremities (30.1%), the neck (17.8%) and the upper part of the body (17.8%). Dieters suffered the most from pain (86.2%) while those exercising to build strength suffered the least with 26.8%. There was a significant relationship between the purpose for exercising and the amount of pain suffered (p<.05). By kind of exercise, pain stroke aerobic exercisers disproportionately with 42.4% while it almost steered clear of exercisers for strengthening with 26.9%. There was significant relationship between the kind of exercise and pain suffered (p<.05). The type of suffering differed by body shape. A significantly higher number of overweight people experienced pain than underweight people (p<.05). 32.8% of pain sufferers commented that the pain affects their workout, and on this issue there was no gender difference (p>.05). The pain caused more difficulties in doing activities of daily living for overweight or obese peoples than underweight peoples (p<.05). More than a third of health club and fitness center users are experiencing musculoskeletal pains. Measures such as professional training or information provision is required to prevent injury or disorder caused by improper exercise.

• Journal of the Korean Institute of Gas
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• v.17 no.6
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• pp.52-57
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• 2013

In this study, the strain energy density, stress and deformation behaviors have been analyzed as functions of a thickness and a force area of protective helmets with and without an extruder on the top of the shell structure using the finite element method. The strain energy density in which is related to the absorption capacity of an impact energy transfer is one of a key element of the helmet safety. The FEM analyzed results show that when the impulsive force of 4,540N is applied on the top surface of the helmets, the maximum stress is linearly reduced for an increased area of impact forces. But, the maximum strain energy density has been reduced for the increased force area. The reduced strain energy density may increase the impulsive forces transferred to the head and neck of helmet wearers, which may decrease the impact energy absorption safety of the helmets. In thus, it is safer design of the helmet in which has an extruded structure on the summit surface, but the modified helmet may decrease the impact energy absorption capacity.

• Environmental Engineering Research
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• v.20 no.1
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• pp.79-87
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• 2015

To treat leather industry wastewater (LIW) containing high nitrogen concentration, eight aerobic denitrifiers were isolated from sludge existing in an LIW-treatment aeration tank. Among them, one strain named as KH8 had showed the great ability in denitrification under an aerobic condition, and it was identified as Pseudomonas aeruginosa R12. The aerobic denitrification ability of the strain KH8 was almost comparable to its anaerobic denitrification ability. In lab-scale aerobic denitrifications performed in 1-L five-neck flasks for 48 hr, denitrification efficiency was found to be much improved as the strain KH8 held a great majority in the seeded cells. From the nitrogen balance at the cell-combination ratio of 10:1 (the strain KH8 to the other seven isolates) within the seeded cells, the percentage of nitrogen loss during the aerobic denitrification process was estimated to be 58.4, which was presumed to be converted to $N_2$ gas. When these seeded cells with lactose were applied to plant-scale aeration tank for 56 day to treat high-strength nitrogen in LIW, the removal efficiencies of $COD_{Cr}$ and TN were achieved to be 97.0% and 89.8%, respectively. Under this treatment, the final water quality of the effluent leaving the treatment plant was good enough to meet the water-quality standards. Consequently, the isolated aerobic denitrifiers could be suitable for the additional requirement of nitrogen removal in a limited aeration-tank capacity. To the best of our knowledge, this is the first report of aerobic denitrifiers applied to plant-scale LIW treatment.

• Journal of Biomedical Engineering Research
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• v.24 no.3
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• pp.233-239
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• 2003

Falling related injuries are categorized as the most serious and common medical problems experienced by the elderly, hip joint fracture, one of the most serious consequences of falling in the elderly, occurs in only about 1% of falling. Nevertheless, hip fracture accounts for a considerable part of the disability, death, and medical costs associated with falling. In this study, we considered the impact angle and displacement rate in falling as another factor affecting femoral strength. Using a fresh-frozen human femur, we developed system to simulate the falling condition and then conducted the experiments changing the impact angle (0$^{\circ}$, 15$^{\circ}$, 30$^{\circ}$) of proximal femur. Also, in order to analyze the relative risk due to falling to normal situation in proximal femur, we did the static test simulating the two-legged stance condition. The results showed that the change in impact angle affected the strain distribution in proximal femur, and that a large deformation in femoral neck than in other sites. Furthermore despite low impact velocity, a large deformation in proximal femur occurred in the impact test and different strain distribution was observed compare to the static case.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.905-909
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• 2001

The significance of casting/forging process for reducing the production cost of large components is being noted in these days. This casting/forging process is a method of forging a workpiece preformed by casting into the final shape. In this study, the casting/forging process has been applied in manufacturing a large aluminum flange in order to determine the optimum forging condition of the aluminum flange. The optimum range of forging temperature of Al 5083 was from $420^{\circ}C$ to $450^{\circ}C$. The suitable strain rate was 1.5 $sec^{-1}$. The deformation amount of a preform in a forging process is key role in the mechanical properties of casting/forging products. In order to find the change of mechanical properties according to effective stain of cast aluminum billets, a hot upsetting test were performed with rectangular blocks and then a uniaxial tensile test was performed with specimens cut from the upsetted billets. The tensile strength and the elongation of cast/upsetted aluminum billets were increased largely until the effective strain was 0.7. FE analysis was performed to determine the configurations of cast preform and die for an aluminum flange. In the FE analysis, the forging load-limit was fixed 1500ton for the low equipment cost. The cast preform was designed so that the effective stain around the neck of a flange exceeds 0.7. In the forging experiment for an aluminum flange, it was confirmed that the optimal configuration of the cast preform predicted by FE analysis was very useful. The cast/forged products using designed preform were made perfectly without any defects.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.3
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• pp.395-407
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• 2008

As global interest in clothing spreads over the smart clothing which arouses high added-value in the apparel industry, this study is to develop a smart jacket with an electrically-vibrating device maintaining excellent appearance and comfort. The vibrating device has a massage function that could relieve muscle pain near shoulders and neck. The purposes of this research are to develop jacket pattern for men in their thirties considering body shapes and fashion trend, to develop a wearable device that is composed of motor and controller and integrate it into a jacket, and to assess the external appearance and functional satisfaction of the smart jacket through the wearing test. The results are as follows: 1. In order to develope an appropriate jacket pattern for men in their thirties, several patterns were assessed for their fitting comfort. The final pattern was completed after making alterations some parts, and showed high satisfaction as 3.6(on a five-point scale) in all categories. 2. A vibrating device was developed by connecting motor, controller, battery and switch. Developing this device, focus was maximizing the strength of motor and minimizing the heat generated from motor and controller. Snaps were placed between inner and outer cloth of jacket so that the vibrating device could be easily attachable and detachable. The motor was located around Trapezius where muscles often get stiff. A switch was designed to be used in selecting the modes of Strong, Weak, and Cross Tapping. 3. The wearing test was conducted to examine outer appearance, comfort for motion, and functionality of the smart jacket. The results of assessing outer appearance showed that the location for attaching the vibrating device was not noticeable but looked natural, and there is almost no change in outer appearance when the vibrating device operates. The result of assessing comfort of action revealed that wearer's satisfaction was high in all categories about activity, wearer's comfort, etc. The result also showed that wear's satisfaction for effects of vibrating massage, easiness in using the device, heat generation was not less than 3.5 in all categories except a category about noise.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.2
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• pp.143-149
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• 2012

용융탄산염 연료전지 상용화를 위해서 40,000 시간이상 장기 운전이 가능해야 한다. 장기운전을 위해 크랙 발생이 적고 기계적 강도가 높은 강화 매트릭스의 개발이 절실히 요구되고 있다. 본 연구에서는 $LiAlO_2$에 알루미늄 나노입자를 첨가하여 매트릭스의 기계적 강도를 향상시키는 연구를 수행하였다. 나노 알루미늄 첨가 $LiAlO_2$ 그린 시트를 수소 분위기에서 열처리한 결과, 공기 분위기에서 열처리한 매트릭스에 비해 기계적 강도가 1.5배 증가함을 확인하였다. 이는 환원분위기에서 열처리를 할 경우, 알루미늄의 입자간의 소결으로 인한 neck이 형성 되어 $LiAlO_2$ 입자 간에 다리를 만들어주는 효과가 나타나 매트릭스의 기계적 강도가 크게 증진되었으리라 판단된다.

• Journal of the Korean Ceramic Society
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• v.36 no.1
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• pp.89-96
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• 1999

Manufacturing conditions of the porous alumina mold were established to overcome various limits of the gypsum mold. For the preparations of the porous alumina mold, an activated charcoal was added to the Al2O3 with the wt% variation and then mixed. The binary slurry was study dispersed based on the examination of the ESA and rheological behaviro. The cylinder type alumina mold was cast in the gyspum mold and characterized by the shrinkage rate at the variable sintering temperature and the resistance against wear. It was proper to make a sintering of the Al2O3 by the surface diffusion which was non-shrinkage sintering mechansim, and intergranular neck growed stronger while sintering was being made. We studied a sintering by three categories; 1) thermodynamic method below 1,000$^{\circ}C$, 2) kinetic method above 1,000$^{\circ}C$ and 3) combined method. In the results of the respective works, combined method was superiro to the others. The prepared Al2O3 mold had relatively high strength, low drying rate, the resistance against the acid or base and good casting behavior.