• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.2
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• pp.1-16
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• 2008

Purpose: In this rearch, we made a plan to investigate the effects of Changbuyeukgun-Tang(CET) on the polycystic ovary(PCOS) induced by estradiol valerate(EV) in rats. PCO was induced by single intramuscular injection with EV(4㎎) in female rats. Rats(n=8) in normal group were injected with sesame oil and orally administrated distilled water for 8weeks Rats in PCO control group(n=8) were injected with EV and orally administrated distilled water for 8weeks. Rats in CET treated group(n=8) were injected with EV and orally administrated CET for 8weeks. Methods: We measured the weights of the body, the ovary, the uterus and the adrenal gland. And also, we analyzed ovarian histopathology, NGF and CRF immunohistochemistry. Results: The results were as follows1. the weights(㎎) of the ovaries in CET treated group were significantly increased(p<0.001) compared with PCO control group. 2. the number of the mature follicles in CET treated group were significantly increased(p<0.01) compared with PCO control. 3. the number of the atresia follicles in CET treated group were significantly decreased(p<0.01) compared with PCO control. 4. the number of the corpora in CET treated group were significantly increased(p<0.05) compared with PCO control. 5. the expressions of NGF-immunoreactive cells in the ovarian granulosa cells of rats in CET treated group were less observed than PCO control group. Conclusion: According to these results, we finally concluded that Changbuyeukgun-Tang(CET) has the inhibitory effect on the development of EV-induced polycystic ovary. And we deduced that the effect of it may be related to the decreased NGF activities in the ovary.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.143-153
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• 2014

This paper presents a novel application of LCC resonant converter for 60kW EV fast charger and describes development of the high efficiency 60kW EV fast charger. The proposed converter has the advantage of improving the system efficiency especially at the rated load condition because it can reduce the conduction loss by improving the resonance current shape as well as the switching loss by increasing lossless snubber capacitance. Additionally, the simple gate driver circuit suitable for proposed topology is designed. Distinctive features of the proposed converter were analyzed depending on the operation modes and detail design procedure of the 10kW EV fast charger converter module using proposed converter topology were described. The proposed converter and the gate driver were identified through PSpice simulation. The 60kW EV fast charger which generates output voltage ranges from 50V to 500V and maximum 150A of output currents using six parallel operated 10kW converter modules were designed and implemented. Using 60kW fast charger, the charging experiments for three types of high-capacity batteries were performed which have a different charging voltage and current. From the simulation and experimental results, it is verified that the proposed converter topology can be effectively used as main converter topology for EV fast charger.

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.1
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• pp.84-98
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• 2007

Purpose : Polycystic ovarian syndrome(PCOS) is a endocrine disorder and still remains as one of the common causes of anovulation in women of reproductive age. There are some evidences that nerve growth factor(NGF) is involved in the pathogenesis of PCOS. In this research, the effects of ShingihwanhapChangbudodam- Tang(SCT) on the estradiol valerate(EV)-induced polycystic ovary(PCO) were investigated in rats. Methods : PCO was induced by single intramuscular injection with EV(4mg) in female rats. Rats in PCO control group(n = 8) were EV injected and orally administrated distilled water for sixty days. Rats in SCT-treated group(n = 8) were EV injected and orally administrated SCT for same duration. The weights of body, ovary and adrenal gland were measured. And also, ovarian histopathology and NGF immunohistochemistry were performed. Results : The weights of ovaries in SCT-treated group were significantly increased compared with control group. The numbers of secondly and mature follicles, and corpora lutea in SCT-treated group were significantly increased compared with control group. The numbers of atretic follicles were significantly decreased compared with control group. The expression of NGF positive reaction in the ovarian granulosa cells of SCT-treated group were lesser observed than control group. Conclusion : From the these results, we concluded that ShingihwanhapChangbudodam-Tang(SCT) has inhibitory effect on the development of EV-induced polycystic ovary. And it's effect may be related with decreased NGF activities in the ovary.

• Agribusiness and Information Management
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• v.6 no.2
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• pp.40-48
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• 2014

As basic research to develop HEV and EV agricultural field machinery, the present study analyzes the technical trend of electric agricultural field machinery through product analysis, paper analysis, and patent analysis concerning HEV and EV in the automobile, construction machinery, and agricultural machinery sectors. For product analysis, the homepages of companies in these sectors were consulted to analyze the number of products of each company. For paper analysis, key words related to HEV and EV were selected, a search formula was drawn up, and articles search sites were consulted. And for patent analysis too, key words were selected and then a search formula was drawn up to examine published patent applications or registered patent applications, and trends were analyzed by structure, country, and year. The number of HEV and EV products were 17 in the automobile area, 8 in construction machinery, and 4 in agricultural machinery. Notably, in the agricultural machinery area, all HEV and EV products were from advanced companies overseas. In terms of papers, papers published in the past 5 years were searched and 33,195 papers were from the automobile area, 3,806 were from construction machinery, and 2,687, the fewest papers, were from the agricultural machinery area. A search of patents in the electric drive technology area in Korea, USA, and Japan, and Europe showed 1,927 valid patents, with 1,120 in Japan, 497 in USA, 193 in Korea, and 117 in Europe. Analysis of the trend of research on electric agricultural field machinery by product, paper, and patent shows the development of HEV and EV technology in Korea is insufficient compared to USA, Japan, and Europe, which means rapid technological development is needed.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.1
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• pp.27-41
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• 2011

Objectives: This study was designed to investigate the effect of Ojeok-san(OJS) on the estradiol valerate(EV)-induced polycystic ovaries(PCO) in rats. Methods: PCO was induced by single intramuscular injection with estradiol valerate(EV)(4mg) in female rats. Normal group(n=8) were injected with sesame oil and orally administrated distilled water for sixty days. PCO control group (n=8) were injected with EV and orally administrated distilled water for sixty days. OJS treated group(n=8) were injected with EV and orally administrated OJS for sixty days. Then, we measured weights of body, ovaries, adrenal glands and uterus of rats. The histomorphometrical changes of ovaries were also evaluated. And we observed the NGF and CRF expression by immunohistochemistry. Results: The results were as follows - The weights(mg) of ovaries in OJS treated group($57.4{\pm}9.4$) were significantly increased(p < 0.05) compared with PCO control group($42.3{\pm}8.5$). - The numbers of mature follicles in OJS treated group($9.3{\pm}2.5$) were significantly increased(p < 0.05) compared with PCO control group($6.1{\pm}2.1$). - The expressions of NGF-immunoreactive cells in the ovarian granulosa cells in OJS treated group were weaker than PCO control group. Conclusion: From the these results, we concluded that Ojeok-san(OJS) has inhibitory effect on the development of EV-induced polycystic ovary. And it's effect maybe related with decreased NGF activities in the ovary.

• Preventive Nutrition and Food Science
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• v.15 no.3
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• pp.189-195
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• 2010

Water extracts from 20 medicinal plants, traditionally used for postmenopausal symptoms in Korea, were examined for their vasorelaxant activity in isolated rat thoracic aorta rings precontracted with norepinephrine (NE). Among the 20 medicinal plants, Cornus officinalis (CoEx, 0.3 mg/mL), Schisandra chinensis (ScEx, 0.3 mg/mL), Erythrina variegate (EvEx, 0.3 mg/mL), and Epimedium koreanum (EkEx, 0.3 mg/mL) showed rapid relaxation of endothelium-intact aorta ($69\pm4%$, $40\pm3%$, $25\pm2%$, and $23\pm3%$ of active tone induced by NE, respectively). In contrast, the extracts of Erythrina variegata (EvEx), Angelica gigas (AgEx), Pueraria thunbergiana (PtEx), and EkEx lead to gradual (i.e., long-term) relaxation to baseline in endothelium-intact vessels. The time to complete relaxation was 20～40 min. These 6 plant extracts were selected for the investigation of possible underlying mechanisms. The CoEx-, ScEx-, or EkEx-induced rapid relaxations were virtually abolished by endothelium denudation, and were significantly inhibited by pretreatment with nitric oxide (NO) synthase inhibitor $N^G$-nitro-L-arginine (L-NNA, 10 ${\mu}M$), indicating that increased formation of NO might contribute to the endothelium-mediated relaxation. In long-term responses, the endothelium denudation did not affect PtEx-induced relaxation, whereas it delayed responses by EvEx and AgEx, and significantly inhibited the effect of EkEx. Among EvEx, AgEx, and PtEx, EvEx attenuated the $CaCl_2$-induced vasoconstriction in high-potassium depolarized medium, implying that EvEx is involved in inhibition of the extracellular calcium influx to smooth muscle through voltage dependent calcium channels. These results provide the scientific rationale for the interrelationships between the use of 20 medicinal plants and their effects on cardiovascular health in estrogen deficient conditions.

• Molecules and Cells
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• v.44 no.10
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• pp.736-745
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• 2021

Although various marine ingredients have been exploited for the development of cosmetic products, no previous study has examined the potential of seaweed extracellular vesicles (EV) in such applications. Our results revealed that EV from Codium fragile and Sargassum fusiforme effectively decreased α-MSH-mediated melanin synthesis in MNT-1 human melanoma cells, associated with downregulation of MITF (microphthalmia-associated transcription factor), tyrosinase and TRP1 (tyrosinase-related proteins 1). The most effective inhibitory concentrations of EV were 250 ㎍/ml for S. fusiforme and 25 ㎍/ml for C. fragile, without affecting the viability of MNT-1 cells. Both EV reduced melanin synthesis in the epidermal basal layer of a three-dimensional model of human epidermis. Moreover, the application of the prototype cream containing C. fragile EV (final 5 ㎍/ml) yielded 1.31% improvement in skin brightness in a clinical trial. Together, these results suggest that EV from C. fragile and S. fusiforme reduce melanin synthesis and may be potential therapeutic and/or supplementary whitening agents.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.205-214
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• 2013

In this paper, we analyzed the various EV charging-infra information(charging status, charging pattern, charging rate, charging fee, etc.) through the charging infra simulator which would be of help to effectively construct the EV charging infrastructure. The proposed simulator virtually made the EV motoring pattern referred to TMS(Traffic Monitoring System) & Ministry of Land, Transport and Maritime Affairs, and analyzed the charging-infra information(amount of charging, accumulated charging fee, etc.) based on vehicle types, charging type, time and days using EV charging-fee list noticed by KEPCO. Through this simulator, we deducted some considerable contents to build the EV charging infrastructure similarly with real environment.

• Polymer(Korea)
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• v.25 no.1
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• pp.63-70
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• 2001

The objective of this study was to investigate the effect of cure type on the processing and physical properties under conditions of similar stress-strain properties. On the carbon black filled natural rubber(NR) based compound, the induction time decreased, but the cure rate became fast with increasing loading of sulfur donor agent. Tensile strength was little affected on the curing type. However, elongation generally decreased with increasing accelerator. Effect of cure type on the blow-out properties was followings: CV

• Journal of Energy Engineering
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• v.20 no.1
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• pp.1-7
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• 2011

The performance and life-cycle costs of electric vehicle(EV) and hybrid electric vehicle(HEV) depend inherently on battery packs. Temperature uniformity in a pack is an important factor for obtaining optimum performance for an EV or HEV battery pack, because uneven temperature distribution in a pack leads to electrically unbalanced battery cells and reduced pack performance. In this work, a three-dimensional modeling was carried out to investigate the effects of operating conditions on the thermal behavior of a lithium-ion battery pack for an EV or HEV application. Thermal conductivities of various compartments of the battery were estimated based on the equivalent network of parallel/series thermal resistances of battery components. Heat generation rate in a cell was calculated using the modeling results of the potential and current density distributions of a battery cell.