• Journal of Korean Medicine for Obesity Research
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• v.7 no.1
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• pp.23-29
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• 2007

Background : Mahuang (Ephedra sinica) has been used widely to treat respiratory disease in traditional medicine for over thousands years. Mahuang preparations contain approximately $0.75{\sim}1%$ ephedrine alkaloids. Recently in North America, the Eephedra alkaloids has aroused a controversy due to its adverse effects in those using whole extracts as "dietary supplements" for weight loss or athletic performance enhancement. Objective : To discuss the need for clinical practice guidelines on the use of Mahuang. Results and Conclusion : It is widely assumed that Mahuang is one of the useful medicines and is safe for human body. Most of scientific literatures support that the safety of Mahuang prescription in common dosage. However, it has been claimed that there were some warnings and apprehensions about the harmfulness of Mahuang as dietary supplements. This article does not negate the fact that it is necessary to pay more attention for use of Mahuang in clinical situations. We assert that the establishment of clinical practice guideline on the use of Mahuang, which is based on scientific materials and consensus, is required in traditional medicine.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.3
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• pp.154-164
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• 2010

Objective : The purpose of this clinical research was to investigate the effects of herbal cosmetics containing Phellinus linteus extracts on patients with atopic dermatitis. Methods : A total of 35 patients who visited Daegu Hanny Oriental Medical Center from November 4th, 2008 to December 28th, 2008 were included in this study. In this study, we observed transepidermal water loss, skin moisture content, modified scorad index of atopic dermatitis and pruritic degree. Statistical analysis was performed by using paired t-test and wilcoxon signed ranks test. Statistical significance was achieved if the probability was less than 5%(p<0.05). Results : Statistically, herbal cosmetics containing Phellinus linteus extracts showed siginificant effect on transepidermal water loss, skin moisture content, modified scorad index of atopic dermatitis and pruritic degree(p<0.05). And satisfaction after using herbal cosmetics was near good. Conclusions : Considering the above results, we have concluded that herbal cosmetics containing Phellinus linteus extracts have the remarkable effects on atopic dermatitis.

• Korean Journal of Optics and Photonics
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• v.14 no.1
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• pp.44-50
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• 2003

This paper describes the thermal effect at Nd:YAG using a laser-diode side-pumping. To detect the depolarization loss and the retardation caused by the thermal effect, a λ/4 plate is inserted between the polarizer and the Nd:YAG laser material. Using a CCD has allowed detection of the variation of the beam pattern that could analyze the change of the refractive index of the Nd:YAG laser material by the thermal effect. Through the change of the probe beam power, we know that 21% of the pumping power was converted into heat in the material. The depolarization loss was 24.7% under a temperature of $25^{\circ}C$ of the laser material and a pumping power of 15 W. The inhomogeneous distribution showed that the retardation angle was 7$^{\circ}$ in the center of the material and 19$^{\circ}$ on the edge of it. It is confirmed that the thermal effect is analyzed at the each point of the laser material and it suggests an effective method to reduce the thermal effect on the LD side-pumped laser material.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.4
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• pp.357-364
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• 2011

In this study, ring-shaped acoustic resonators were proposed to be installed in a silencer to increase the acoustic performance of silencer in the low-frequency range. Evaluation of noise reduction performance of acoustic resonator arrays was carried out by measuring the random-incidence absorption coefficient. It was found that the absorption coefficient of resonator array was measured up to 1 at 125 Hz of 1/3-octave band center frequency. Insertion losses of silencers with ring-shaped acoustic resonator arrays were measured based on ISO 7235. The results were shown that the ring-shaped resonator could increase the insertion loss up to 13 dB without flow, whereas 7 dB when flow speed reached 15 m/s. As increasing the flow speed above 15 m/s, the effect of acoustic resonator decreased due to the effect of nonlinear air damping of the resonator. It was also found that the increment of pressure drop by the presence of resonator arrays was about 9 % at flow speed of 25 m/s.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.398-399
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• 2008

Enhanced performances of high temperature superconducting (HTS) cable attract tremendous interests of the power utility. However, the reliability issue as the power system is still in controversy. To verify the reliability of HTS cable, 22.9 kV HTS cable system with the specification of 100 m length, 50 MVA capacity, and open refrigeration cooling system was laid on Gochang power testing center of KEPCO in 2006. During the test period, the current transport characteristics, the fundamental function of power cable, have been monitored and investigated precisely. In this paper, the heat loss and AC loss measured at various current load conditions are described and discussed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.3
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• pp.29-35
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• 2020

This paper studies the main parameters of tube-to-bar dissimilar material and shape friction welding for piping materials. The weldability of joint parts was investigated with respect to tensile tests, micro-Vickers hardness, the bond of area, and optical microstructure. The specimens are tested as-welded. Optimal welding conditions are n = 2000 rpm, HP = 50 MPa, UP = 100 MPa, HT = 5 sec, and UT = 10 sec when the metal loss (Mo) is 11 mm. Moreover, the same two materials for friction welding are strongly mixed with a well-combined structure of micro-particles without any molten material, particle growth, or defects. Therefore, the expected result of dissimilar material friction welding includes a reduction of cost and material in the welding process.

• The Korean Journal of Rehabilitation Nursing
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• v.13 no.1
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• pp.62-69
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• 2010

Purpose: The purpose of this study was to evaluate the effects of an integrative weight control program including East Asian traditional medicine on the degree of obesity and body compositions. Method: Using one group pre-post test design, 63 subjects aged 19 years or older were conveniently recruited from D University hospital. The weight control program consisted of acupuncture, aerobic exercise, moderate caloric restriction, and behavioral modification for weight loss. Paired t-tests were conducted using the SPSS V18.0. Results: Body weight (t=10.44, p<.001), body fat mass (t=11.47, p<.001), percentage of body fat (t=11.49, p<.001), the degree of obesity (t=10.48, p<.001), body mass index (t=10.66, p<.001), waist circumference (t=10.25, p<.001), hip circumference (t=6.10, p<.001), and WHR (t=2.21, p=.040) decreased after administering the integrative weight control program. Conclusion: This integrative weight control program effectively reduced the obesity degree and percentage of body fat. Further study is needed to replicate our program in a larger sample with control group to validate the findings.

• Tribology and Lubricants
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• v.30 no.2
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• pp.116-123
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• 2014

The objective of this study is to model and simulate the nonlinear lubrication performance of the sliding part between the piston and cylinder wall in a hydrostatic swash-plate-type axial piston pump. A numerical algorithm is developed that facilitates simultaneous calculation of the rotating body motion and fluid film pressure to observe the fluid film geometry and power loss. It is assumed that solid asperity contact, so-called mixed lubrication in this study, invariably occurs in the swash-plate-type axial piston pump, which produces a higher lateral moment on the pistons than other types of hydrostatic machines. Two comparative mixed lubrication models, rigid and elastic, are used to determine the reaction force and sliding friction. The rigid model does not allow any elastic deformation in the partial lubrication area. The patch shapes, reactive forces, and virtual local elastic deformation in the partial lubrication area are obtained in the elastic contact model using a simple Hertz contact theory. The calculation results show that a higher reaction force and friction loss are obtained in the rigid model, indicating that solid deformation is a significant factor on the lubrication characteristics of the reciprocating piston part.

• Applied Science and Convergence Technology
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• v.24 no.6
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• pp.224-227
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• 2015

Ferroelectric $Pb_2(Sc,Nb)O_6$ were prepared under two different sintering conditions using the oxide mixing method and the electrical properties were measured. The sintering conditions were $1350^{\circ}C$ for 25 minutes and $1400^{\circ}C$ for 20 minutes. EDX spectroscopy and XRD were used to determine the crystalline characteristic of the $Pb_2(Sc,Nb)O_6$ compositions Pyrochlore phase showed about 2% in all $Pb_2(Sc,Nb)O_6$ specimens. It expands the growth of crystals in samples sintered at $1400^{\circ}C$ than $1350^{\circ}C$, but all samples were the optimal crystallization. The temperature and frequency dependence of the complex dielectric constant and admittance were measured to analyze the electrical properties. The high dielectric constant of the specimens reflects the good stoichiometry and crystallization. The maximum value of the dielectric constant in the two specimens treated with sintering at $1350^{\circ}C$ and $1400^{\circ}C$ were more than 27,000, and the dielectric loss at room temperature is smaller than 0.05. The maximum dielectric constant decreased with increasing frequency, the transition temperature also increased in $Pb_2(Sc,Nb)O_6$ compositions. The admittance and susceptance values reach a peak at all temperatures, and the magnitude of the peak increases with increasing measuring temperature. Strong frequency dependent of maximum admittance, susceptance, dielectric constant and dielectric loss were observed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.3
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• pp.685-689
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• 2006

In order to examine the injury of vascular endothelial cells related with oxidative stress of reactive oxygen species(ROS), mophological changes of vascular endothelial cells were observed by light microscope after bovine pulmonary vascular endothelial cell line (BPVEC) was treated with 15 uM of hydrogen peroxide. In addition, the effect of vitamin E against ROS-induced oxidative stress was examined by light microscope. In this study, the cell number of BPVEC treated with ROS has significantly decreased than that of control, and the loss of cytoplasmic processes and cell swelling were observed in BPVEC treated with ROS. Whereas, cell number of BPVEC treated with vitamin E has significantly increased than that of BPVEC treated with ROS and also, cytoplasmic processes of BPVEC treated with vitamin E were preserved as control. These findings suggested that not only did ROS induce damage of BPVES by decrease of cell number, loss of cytoplasmic processes and cell swelling, but vitamin E also has protective effect against ROS-induced oxidative stress in cultures of BPVEC.