• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.6
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• pp.1092-1098
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• 2007

Since one decade, the detection of HFPD (High frequency Partial Discharge) has been proposed as one of the effective method for the diagnosis of the power component under service in power grids. As a tool for HFPD detection, Metal Foil sensor based on the embedded technology has been commercialized for mainly power cable due to its advantages. Recently, for the on-site noise discrimination, several PA (Pulse analysis) methods have been reported and the related software, such as Neural Network and Fuzzy, have been proposed to separate the PD (Partial Discharge) signals from the noises since their wave shapes are completely different from each other. On the other hand, the relevant fundamental investigation has not yet clearly made while it is reported that the effectiveness of the current methods based on PA is dependant on the types of sensors. Moreover, regarding the identification of the vital defects introducible into the Power Cable, the direct identification of the nature of defects from the PD signals through Metal Foil coupler has not yet been realized. As a trial for solving above shortcomings, different types of software have been proposed and employed without any convincing probability of identification. In this regards, our novel algorithm 'PA Map' based on the pulse analysis is suggested to identify directly the defects inside the power cable from the HFPD signals which is output of the HFCT and metal foil sensors. This method enables to discriminate the noise and then to make the data analysis related to the PD signals. For the purpose, the HFPD detection and PA (Pulse Analysis) system have been developed and then the effect of noise discrimination has been investigated by use of the artificial defects using real scale mockup. Throughout these works, our system is proved to be capable of separating the small void discharges among the very large noises such as big air corona and ground floating discharges at the on-site as well as of identifying the concerned defects.

• Applied Biological Chemistry
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• v.48 no.2
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• pp.161-165
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• 2005

Ethanol extracts were prepared from 40 herbs, the extracts of herbs were tested their microbial inhibition activities against Helicobacter pylori. Antimicrobial activity against H. pylori was shown by clear zone and inhibition of cell growth in 24 herbs and 26 herbs extracts. Antimicrobial activity showed the high value in ethanol extracts of Salvia officinalis, Phlomis fruticosa, Creeping Rosemarinus officinalis, Lavandula, Cymtpogan citratus, Rosemarinus officinalis, Cherry Salvia officinalis, Hypericum perforatum, Ruta graveloens, Thymus vulgaris, Oreganum vulgare and Salvia officinalis. Phenol content of herb extracts have high concentration as $134.3-533.33\;{\mu}g/ml$, respectively.

• Journal of Environmental Science International
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• v.17 no.5
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• pp.509-516
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• 2008

New functional surfactant, N,N-dimethyl-N-dodecyl-N-(2-methyl benzimidazoyl) ammonium chloride(DDBAC) having benzimidazole(BI) functional group have been synthesized and the critical micellar concentration of DDBAC measured by surface tentiometry and electric conductivity method was $8.9{\times}10^{-4}M$. Micellar effects in DDBAC functional surfactant solution on the hydrolysis of p-nitrophenylacetate(p-NPA), p-nitro-phenylpropionate(p-NPP) and p-nitrophenylvalerate(p-NPV) were observed with change of various pH (Tris-buffer). The pseudo first rate constants of hydrolysis of p-NPA, p-NPP and p-NPV in optimum concentration of DDBAC solution increase to about 160, 280 and 600 times, respectively, as compared with those of aqueous solution at pH 8.00(Tris-buffer). It is considered that benzimidazole functional moiety accelerates the reaction rates of hydrolysis because they act as nucleophile or general base. In optimum concentration of DDBAC solution, the rate constants of hydrolysis of p-NPP and p-NPV increase to about 1.5 and 3.0 times, respectively, as compared with that of p-NPA. It means that the more the carbon numbers of alkyl group of substrates, the larger the binding constants between DDBAC micelle and substrates are. To know the hydrolysis mechanism of p-NPCE(p-NPA, p-NPP and p-NPV), the deuterium kinetic isotope effects were measured in $D_2O$ solutions. Consequently the pseudo first order rate constant ratios in $H_2O$ and $D_2O$ solution, $k_{H_2O}/k_{D_2O}$, were about $2.8{\sim}3.0$ range. It means that the mechanism of hydrolysis were proceeded by nucleophile and general base attack in approximately same value.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.4
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• pp.470-476
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• 2008

In this paper, we describe the cause of TDMA noise and distinction method of TDMA noise source in a GSM mobile phone. The causes of TDMA noise are composed of RF(Radio Frequency) energy coupling and low frequency energy coupling by burst ripple. We propose the distinction method of TDMA noise source from output(TDMA noise measurement) and frequency response of a system(audio path). Especially we propose a method of insertion loss($S_{21}$) analysis and the improvement method for RF energy coupling. Capacitor(40 pF) is a solution to reduce RF energy coupling and therefore TDMA noise was reduced by 10 dB.

• The Journal of Korean Medicine
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• v.32 no.6
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• pp.122-130
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• 2011

Objectives: This study was designed to investigate the effect of herbal extract medicines for inpatients with fever symptoms in an oriental medicine hospital. Methods: Medical records of inpatients who experienced over $38^{\circ}C$ of fever from July 2010 to August 2011 has been requested with deleted personal identifiable information. The requested data were analyzed by patients' general characteristics, administrated western/herbal medicines, and changes in the body temperature of four administration groups (group 1, herbal extract medicine only; group 2, western medication(antibiotics/antipyretics) only; group 3, combination of herbal extract medicine and western medication; group 4, no medication control). The SPSS 19.0 was used for statistical analysis and p-value of less than 0.05 was regarded significant. Results: The body temperature has significantly dropped over time in the herbal extract medicine only group (p<0.001) along with the antibiotics/antipyretics only group. When both treatments were combined, stronger antipyretic effect was shown compared to the sole treatment of herbal extract medicine or antibiotics/antipyretics. Conclusion: The use of herbal extract medicines may be effective in alleviation of fever.

• Korean Journal of Community Nutrition
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• v.16 no.5
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• pp.580-591
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• 2011

This research was performed to investigate the effects of NEP (Nutritional Education Practice) program developed by KHyDDI (Korea Hypertension Diabetes Daegu Initiative) for hypertension and diabetes patients. The subjects were 116 patients (hypertension 70, diabetes 46) who had completed basic education program at the education information center and four-session program was implemented for them. Nutrient intake was analyzed and compared before and after the program by 24-hr recall method and evaluate weight, waist circumference, body fat, blood pressure and eating habits in terms of nutrition knowledge, eating behavior, salty taste assessment. The improved results after the program were observed in weight, waist circumference, body fat ratio, blood pressure, slightly salty taste in salty taste assessment, nutrition knowledge, eating behavior, sodium, energy, carbohydrate and protein intake ratio to total energy (p < 0.001). Therefore, this program is effective in the improvement of weight, waist circumference and eating behavior, and the continued management would lead to the prevention of cardio-cerebrovascular diseases in the community.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.3
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• pp.71-83
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• 2020

Resilience is the capacity to maintain essential services under a range of circumstances from normal to extreme. It is achieved through the ability of assets, networks, systems and management to anticipate, absorb and recover from disturbance. It requires adaptive capacity in respect of current and future risks and uncertainties as well as experience to date. The agricultural infrastructures with high resilience can not only reduce the size of the disaster relatively, but also minimize the loss by reducing the time required for recovery. This study aims to evaluate the most suitable drought countermeasures with the analysis of various resilience indices by predicting future agricultural water shortage under land use and climate change scenarios for agricultural areas in Jeju Island. The results showed that the permanent countermeasure is suitable than the temporary countermeasures as drought size and the cost required for recovery increase. Wide-area water supply system, which is a kind of water grid system, is identified as the most advantageous among countermeasures. It is recommended to evaluate the capability of agricultural infrastructure against drought with the various Resilience Indices for reliable assessment of long-term effect.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.159-163
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• 2005

This study was conducted to investigate the effect of simulated acid rain (SAR) on growth and antioxidant system in french marigold (Tagetes patula L.). Plants were subjected to four levels of SAR (pH 5.6, 4.0, 3.0, 2.0) in the growth chambers for 2 weeks. SAR decreased both plant height and plant dry weight of french marigold. As the pH levels decreased from 5.6 to 2.0, the content of MDA highly increased linearly. The ratios of dehydroascorbate/ascorbate and oxidized glutathione/reduced glutathione were significantly increased with decreasing pH levels. The enzyme (superoxide dismutase, ascorbate peroxidase etc.) activities of the plant affected by SAR were increased as the pH decreased. Based on the results, SAR caused oxidative stress in french marigold and resulted in significant reduction in plant growth. Biochemical protection responses might be activated to prevent the plant from damaging effects of oxidative stress generated in SAR.

• Journal of Yeungnam Medical Science
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• v.33 no.1
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• pp.40-43
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• 2016

Retroperitoneal fibrosis (RF) is a disorder characterized by the presence of a retroperitoneal mass and concurrent systemic inflammation. Some cases of RF are recognized as belonging to the spectrum of immunoglobulin G4-related disease (IgG4-RD). Glucocorticoids are highly effective for treatment of retroperitoneal fibrosis, although the optimal dose and duration of therapy have not been established. An initial dose of prednisone (40-60 mg) daily is usually administered with a tapering scheme. We report on a 55-year-old man diagnosed with IgG4-related RF and successfully treated with a 3-day course of daily 250 mg (4 mg/kg) intravenous methylprednisolone, which resulted in the prompt resolution of urinary obstruction and systemic symptoms.

• Journal of Pharmaceutical Investigation
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• v.33 no.2
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• pp.121-127
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• 2003

The objective of this study was to solidify the simvastatin self-microemulsifying drug delivery system (SMEDDS) and to improve the encapsulation efficiency of solidified alginate beads using sodium alginate. Typical simvastatin SMEDDS was composed of various oils, surfactants and cosurfactants. Also solidified-alginate beads was prepared by crosslinking liquid emulsion mixtures containing sodium alginate and other excipients (cetylpyridinum chloride (CP-Cl), hydroxypropyl methylcellulose, starch and so on). in $CaCl_2$ solution, it has been investigated that the drug release pattern and encapsulation efficiency were varied with the ratio of cationic lipid (CP-Cl). Solidified sodium alginate beads containing simvastatin SMEDDS were redispersed into media without re-aggregation. Oil droplet size of redispersed solidified-beads in media produced smaller than the initial size. The density of beads and drug loading amount were increased with increasing cationic lipid content. These systems have advantages of storage stability and predictability of drug release rate.