• Journal of the Korean Vacuum Society
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• v.9 no.4
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• pp.360-366
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• 2000

$Sr_xBi_{2.4}Ta_2O_9$ (SBT) thin films of 150 nm thickness were prepared using LSMCD (Liquid Source Misted Chemical Deposition) process with variation of the Sr/Ta mole ratio of 0.35~0.65, and their crystalline phase, microstructure, ferroelectric properties and leakage current characteristics were investigated. Ferroelectric characteristics of the LSMCD-derived SBT films were optimized at the Sr/Ta moleratio of 0.425. The remanent polarization (2Pr) and coercive field (Ec) of the SBT film with the Sr/Ta mole ratio of 0.425 were measured as 15.01 $\mu$C/$ \textrm{cm}^2$ and 41 kV/cm at an applied voltage of $\pm$5 V respectively. LSMCD-derived SBT films with the Sr/Ta mole ratio of 0.35~0.5 exhibited leakage current densities lower than $10^{-5} A/\textrm{cm}^2$ at an applied field of 100 kV/cm, and excellent fatigue-free characteristics of the remanent polarization decrement less than 1% after $10^{10}$ switching cycles at$\pm$5 V.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.11
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• pp.1119-1124
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• 2017

The stabilizer bar mounted on the vehicle underbody makes for a more comfortable ride by holding the vehicle itself when the vehicle is cornering. Stabilizer bars are available in two types: solid and tube. To lighten the weight of the vehicle, and owing to weight reduction requirements, tubular stabilizer bars are increasingly being used. Tubular stabilizer bars can be fabricated to be over 34％ lighter than solid bars, but the lifetime of the product tends to decrease rapidly as the weight ratio increases. However, the durability can be improved by utilizing high-strength and high-hardness materials for the stabilizer bar or by improving the shot peening method.

• Journal of the Korean Society for Heat Treatment
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• v.2 no.4
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• pp.47-55
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• 1989

The effects of thermal cycle, aging heat treatment and Boron addition on the phase transformation characteristics and mechanical properties of the shape memory alloys of Cu-Zn-Al system, which was designed to operate about $80^{\circ}C$ by this research group, were studied. From the view point of the effects of thermal cycle on the phase transformation temperature change, it was found that up to 100 cycles Ms and Af points increased by $3-7^{\circ}C$ and Mf decreased a little bit and after that all of them were remain constant, and As point was not affected. All of the phase transformation temperatures were decreased $5-7^{\circ}C$ by aging heat treatment, at $140^{\circ}C$ for 24h however the effects of thermal cycle on aged alloys were same as on unaged alloys. As the thermal cycle increased the shape memory ability decreased a little up to 20 cycles, but above that it kept almost same ability. By Boron addition, grain size was refined from $1500{\mu}m$ to about $330{\mu}m$ and the hardness, fatigue property were improved but shape memory ability was lowered.

• Fashion & Textile Research Journal
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• v.6 no.6
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• pp.810-814
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• 2004

This study is one of the fundamental researches for the development of future smart clothing and textile products using silver(Ag) nano powder. Our study was focused on the blocking or insulating effects of nano-processed textiles from electromagnetic waves. Also, for the surveying of the actual effect to human body, we measure the variation of electroencephalogram which is an indication of human physical symptoms. Among various textiles in this experiment, nano silver processed case has shown the best blocking performance from the electromagnetic waves, which decreases depending on the distance. As a reference model of working environment, we setup the visual stimuli object on the computer that is a source of electromagnetic wave. The power spectrum distribution and the incidence of electroencephalogram was measured. The analysed data has shown that, with nano-processed textiles, ${\beta}$ wave does not appear very often where ${\beta}$ wave appears only to illustrate the stable states of human's body. However, as for the materials without nano processing, the ratio of ${\gamma}$ waves in the total level of electroencephalogram becomes higher in spite of short exposure to visual stimuli in work environment, which shows that the worker becomes stressed. The ${\beta}$ wave electroencephalogram of all materials is drawn in calcarine fissure of occipital lobe to show the convergent distribution, and stronger with block-processed Nano Silver Silk(NSS). The study based on the potential risks of human diseases such as physical fatigue by electromagnetic waves, and has shown that the application of Nano Silver textile for human uses require a proper particle size of it which would not penetrate cellular tissues, and a proper binder and binding treatment for it. However, it is highly required for back-up researches to verify various aspects in applying nano silver to textile products.

• International Journal of Highway Engineering
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• v.6 no.1 s.19
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• pp.25-36
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• 2004

The total length of paved roads in Korea is 67,265 Km, and among these roads, about 40% of the national highways and 98% of local roads are paved with asphalt concrete. The major distress to asphalt pavement is rutting and fatigue crack. The permanent deformation including rutting accounts for about 75% of this distress. UTW(Ultra-Thin Whitetopping), which is known for its high-quality performance in asphalt pavement with rutting and cracking, seems to reduce maintenance costs significantly if it is used as the maintenance/repair method for domestic asphalt pavement. In the research, static load test was conducted to establish a behavior of Whitetopping under traffic and environmental condition. It showed that the effect of the thickness of the concrete layer and the temperature change was significant. In addition, the tensile strain as the wheel load position was close to interior and edge of concrete slab were increased up to 75% of maximum tensile strain. It showed that joint spacing must be considered in UTW design procedure.

• The Journal of Internal Korean Medicine
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• v.28 no.3
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• pp.624-631
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• 2007

Hypothyroidism is a common disease of the endocrinal system, characterized by fatigue, cold intolerance, bradycardia, and so on. Subclinical hypothyroidism is a common biochemical abnormality which can be found in routine screening tests of thyroid function. It is defined as an asymptomatic state which characterized by normal free thyroxine(FT4) and elevated thyroid stimulating hormone(TSH) levels. The purpose of this study was to evaluate the effect of treatment with palmijihwang-tang and to observe the changes in triiodothyronine(T3), free thyroxine(FT4), thyroid stimulating hormone(TSH) level and VAS of cold intolerance, hoarseness, dry skin. After the treatment, triiodothyronine(T3) increased from 57.12ng/dl to 120.53ng/dl. Free thyroxine(FT4) increased from 12.59pg/ml to 14.21pg/ml. Thyroid stimulating hormone(TSH) decreased from 10.61mU/L to 1.57mU/L. Cold intolerance, hoarseness and dry skin changed for the better. These results support a role for oriental medical therapy in treating subclinical hypothyroidism. Further case studies of herbal treatment of this ailment are needed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.306-309
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• 2004

Liver cirrhosis is caused by virus, alcohol, toxins, drugs and chronic hepatitis. Clinical symptoms of liver cirrhosis are severe fatigue, nausea, fever, dyspepsia, anorexia, RUQ pain, jaundice, ascites. We applied oriental medicines to patient who had chronic hepatitis and liver cirrhosis. Sodalgeonbitang-gamibang has been used to treat hepatitis and liver cirrhosis because of its beneficial effects. The patient symptoms began to improve after about one month of treatment. After medication we could find remarkable effect on clinical symptoms and blood test. So we hope that this clinical study is helpful in treat a patient with hepatic disease.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.206-219
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• 2010

To establish the fundament for EBM of Traditional Korean Medicine, the papers on Sagunja-tang(Sijunzi-tang) frequently used in medical institutions of Traditional Korean Medicine were analyzed through researching domestic and international papers. The papers were classified by the registration of domestic or international journals, the year of publishment, experimental fields and the kinds of studies on biological activities. Of total 228 papers on Sagunja-tang(Sijunzi-tang), 121 volumes were selected according to creteria. 47 volumes were published in domestic journals, 71 in Chinese journal, 2 in Japanese journal, and 1 in Taiwan journal. The papers on instrumental analyses were preceeded by HPLC, MS, GC with standard compounds of herbal medicine in Sagunja-tang(Sijunzi-tang). The papers on biological activities of Sagunja-tang(Sijunzi-tang) showed improvement of gastrointestinal activity and blood circulation, immunoactivity, anti-cancer, anti-oxidant, anti-fatigue, anti-stress, pharmacokinetics, hepatic protection, radioprotection, muscular activity, hematopoiesis and nontoxical effect. Further studies including gastrointestinal disorder, immune related disease, cancer, oxidative injury and pharmacokinetic study need to be preceeded to establish the fundament for EBM of Sagunja-tang(Sijunzi-tang).

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.252-257
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• 2004

The purpose of this study was to investigate the variation in constituent element of blood between the massage group and non-massage group in the period of convalescence after giving intense physical exercise for ten T'ae-Kwondo martial artists. In the variations of red blood cells, white blood cells, hematocrit, hemoglobin and blood platelet, levels decreased during the rest time after physical exercise, but the subjects in the massage group showed lower tendency than the subjects in the non-massage group after physical exercise. The variation of calcium showed an ascension tendency in the massage group after physical exercise. Creatine phosphokinase was increased after physical exercise, but it showed a tendency of rapid decrease in the massage group. Lactic acid showed a variation increase after physical exercise. It showed a tendency of decrease during the rest time in the non-massage group, but it was increased after sports massage. The variation of blood glucose was increased after physical exercise. It was maintained in the massage group after physical exercise in contrast to the non-massage group whose levels decreased during the rest time.

• Korean Journal of Digital Imaging in Medicine
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• v.16 no.1
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• pp.7-11
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• 2014

The body to achieve an interaction that are connected to each other. Foot of which plays an important role in motor activity. Insole that has been recently used, have a dynamic functional elements. In particular, support of Arch plays a very important role in terms of a motor function of the human body as a whole. It is possible to predict the proper support Arch with insole, the overall structure of the body there can affect the balance. In this study, by applying the insole which supports the Longitudinal arch and Transverse arch, you are trying to assess the interaction of balance and the body's ability. To target the 20 there is no problem in the sense of balance, college student, and changes were observed by measuring the Center of Position area and distance through the Biorescue device worn before and after led by Arch support. As a result, I showed improved results significantly discount rate after wearing in the Center of Position area and distance to assess the balance ability. Therefore, the correction insole function is to support the Longitudinal arch and Transverse arch to an important role in the foot. It may be that it has a functional element for improving the balance of the function of preventing collapse of the arch during walking, to disperse the weight of the entire foot, us reduce fatigue in the end.