• Title/Summary/Keyword: 감극성

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An Improved Single-Phase Zero-Voltage Transition Soft-Switching Inverter with A Subtractive Coupled Inductor Auxiliary circuit (하나의 감극성 커플드 인덕터 보조 회로를 갖는 발전된 영전압 천이 소프트-스위칭 인버터)

  • Lim, Jong-Yeop;Soh, Jae-Hwan;Kim, Rae-Young
    • Proceedings of the KIPE Conference
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    • 2016.07a
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    • pp.307-308
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    • 2016
  • 본 논문에서는 하나의 감극성 커플드 인덕터 보조 회로를 갖는 발전된 영전압 천이 소프트-스위칭 인버터를 제안한다. 기존에 제안된 소프트-스위칭 인버터의 큰 커패시터나 추가 회로의 필요성과 같은 구조적 단점을 극복하였다. 또한, 하나의 커플드 인덕터 보조 회로를 이용하여 풀-브리지 인버터를 구현하여 보조 회로의 소자 수를 줄여 가격과 부피에서 장점이 있다. 본 논문에서 제안된 회로의 동작 원리와 특성들을 다룰 것이며 시뮬레이션을 통하여 유효성을 검증하였다.

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CASE STUDY : FLUOXETINE INDUCED MANIA IN A SCHIZOPHRENIC PATIENCT AND REVIEW OF LITERATURES (정신분열증 여아환자에서 Fluoxetine 투여후 발생한 조증 증례보고 및 문헌고찰)

  • Kim, Bung-Nyun;Cho, Soo-Churl
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.6 no.1
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    • pp.116-122
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    • 1995
  • 목적 : 다음과 같은 fluoxetine으로 유발된 조증 증례를 보고한다. 이와 함께 fluoxetine사용이후 보고된 조증 증례보고를 모아서 정리하고 함께 문헌고찰을 하였다. 증례요약 : 가족력상 기분장애의 병력이 없었으며, 다른 주요 정신과적 질환의 병력은 없었다. 환아는 개인력상 5세경에 주의력 결핍, 과잉행동의 양상을 보였던 병력이 있었고, 13세때에 피해 망상, 환청이 지속되어 haloperidol로 치료받기 시작하였다. 이후 피해 망상의 내용을 언급하거나 환청에 영향받는 행동은 없어졌고 간혹 우울감을 호소하였다. 이후 정신분열증의 진단 하에 haloperidol만으로 3년간 유지하였다. 1994년 환아는 18세때 고3이 되면서 대입에 대한 걱정과 신체적인 허약감을 자주 호소하며, 우울증상이 두드려져 fluoxetine 20mg를 3일간 투여하던 중 갑자기 조증의 임상적 양상을 보이기 시작하여 본원의 입원치료를 받게 되었는데, 입원당시 보인 임상양상은 앙양된 기분, 이자극성(irritability), 사고의 비약, 연상의 이완과 지리멸렬, 과대망상, 피해망상, 관계망상, 환청 등이었고 사람, 장소, 시간에 대한 지남력까지 일시적으로 상실되는 심헌 정신병적 조증상태였다. 토의 : fluoxetine 사용이후 현재까지 세계적으로 문헌상 보고된 14개의 증례보고를 모아서 정리하였다. fluoxetine-induced mania의 병태생리학적인 기전은 명확하지 않지만 가능한 기전에 대해 토론하였다. 이 약물의 중대한 부작용중의 하나인 조증을 예방하기 위해, 이 약물을 다루는 의사는 가능한 조증 발병의 위험인자들에 대하여 인식하고, 약물의 용량조절시에도 주의를 하여야 한다. 가능한 발병 위험인자들에 관해서도 검토하였다.

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Selective Adsorption of Flavonoids Compounds from the Leaf of Ginkgo biloba L. (은행(Ginkgo biloba L)의 잎으로부터의 Flavonoids 화합물의 선택적 흡착)

  • 윤성용;최원재박종문
    • KSBB Journal
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    • v.11 no.6
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    • pp.726-732
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    • 1996
  • Selective adsorption of plant metabolites from a polar dilute solution onto a polycarboxyl ester sorbent (XAD-7) was investigated. Experimental results demonstrated that neutral resins could selectively concentrate specific flavonoids from dilute aqueous mixtures. Adsorption was dependent on the pH of medium, dosage of the resins and medium composition. Especially the medium composition was a key factor for the selective adsorption and it was found that the selective adsorption was dependent on specific sorbent-sorbate-medium characteristics. Under the optimum condition, selectivity increased up to 85% and the yield of recovery was approached to 98%. It was also found that XAD-7 adsorbed flavonoids in the order of hydrophobicity.

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Dipole과 quadrupole 성분의 변화에 의한 SC 24/25 극소기의 태양 자기장의 예측

  • Kim, Bo-Gyeong;O, Su-Yeon;Lee, Yu
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.128.1-128.1
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    • 2012
  • 최근 태양주기 21, 22, 23을 지나 24주기로 감에 따라 태양활동의 지표인 태양상수, 행성간 자기장, 태양극자기장 등과 같은 여러 태양물리량들이 감소하여 태양 활동이 약화되었고 23/24주기의 극소기가 길어졌다. 태양 자기장의 극성은 대체로 Dipole의 형태로 근사하여 나타나지만 dipole 뿐만 아니라 Quadrupole 등과 같은 다중극의 합으로 나타난다. 본 연구에서는 Wilcox Solar Observatory (WSO)에서 제공하는 21주기부터 23주기 동안의 총 태양 자기장의 구조화 함수 coefficient의 세기, dipole 성분 및 Multipole 성분의 변화를 분석하였다. 분석 결과 최근 23 태양주기 시작 이후로 총 태양 자기장의 세기가 감소하는 추세를 보이며 21, 22주기에 비해 23주기에 multipole 성분 보다 dipole 성분이 더 큰 감소율을 보여 dipole이 약해지고 multipole이 강해진 것을 알 수 있었다. 그러므로 태양활동 변화에 Multipole 성분도 중요한 역할을 한다고 볼 수 있다. 전반적으로 태양활동 극대기에는 dipole의 세력이 약하고 극소기에는 dipole의 세력이 강하게 나타난다. 또한 태양주기 23/24의 극소기일 때, 다중극 성분 중 특히 Quadrupole 성분이 차지하는 비율이 두드러지게 증가하였다. 태양활동 극소기에 23/24주기처럼 태양활동이 더 저조해지면 상대적으로 quadrupole 성분이 증가하게 되는 것으로 여겨진다. 그러므로, 다음 태양주기 24/25의 극소기에는 태양활동이 더 약해져서 Quadrupole 성분이 더욱 두드러지게 증가하게 될 것으로 예측된다.

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Anti-oxidant Property and Tyrosinase Inhibition Activity of Various Extracts from plants in Compositae plants (국화류 추출물의 항산화 및 멜라닌 생성 억제 활성)

  • Kang, Jeong-Ran;Lee, Mi-Kyung;Kang, Sang-Mo
    • Applied Biological Chemistry
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    • v.51 no.4
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    • pp.321-328
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    • 2008
  • The research was conducted to identify the antimicrobial effect, anti-oxidative effect and tyrosinase inhibitory effect of MeOH 80% extract and n-hexane, chloroform, ethyl acetate, n-butanol and water fractions from the extract of six kinds of compositae plants, which are naturally grown across the nation. In the antimicrobial effect, the extract and chloroform fraction of Arctium lappa and hexane/ethyl acetate fractions of Taraxacum platycarpum exhibited significant inhibition. In case of antioxidant effect, the extract of Artemisia capillaries showed the highest effect and ethyl acetate/butanol fractions of all plants showed about 90%, which fractions were more polar than the fractions that showed antimicrobial effect. In case of tyrosinase activity, only the MeOH 80% of Arctium lappa among the extracts showed a potent inhibition, and butanol fraction of Chrysanthemum indicum, as well as ethyl acetate/water fractions of Artemisia capillaries showed 48, 38, and 37% respectively, which were higher than control group (arbutin). These active fractions in tyrosinase inhibition also were higher polarity than those that showed antimicrobial effect. In MeOH 80% extracts, only Arctium lappa was found to have antimicrobial, anti-oxidant and tyrosinase inhibitory activity, however there was no fraction to show effects commonly in the three assay system.

Separating of Falcarinol from Acanthopanax senticosus (가시오가피(Acanthopanax senticosus)에서 polyacetylene계 화합물인 falcarinol의 동정)

  • Kim, Seong-Ju;Chang, Kyu-Seob
    • Korean Journal of Food Science and Technology
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    • v.37 no.3
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    • pp.360-363
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    • 2005
  • To detect falcarinol in Acanthopanax senticosus, its stem and bark were extracted with methanol fractionated with petroleum ether and diethyl ether, and separated by silica gel column chromatography, Resulting six crude samples were compared with standard falcarinol through TLC on silica gel plates. Fraction 6 showed $R_{f}$ value of 0.46 similar to that of standard falcarinol. Through analytical reverse phase HPLC/PDA, UV spectra of standard falcarinol and traction 6 recorded between 200 and 340 nm showed identical peaks and UV spectra patterns. GC/MS revealed standard falcarinol and fraction 6 have equal retention times of 7.4 and 8.5 min before and after TMS-derivatization, respectively. Standard falcarinol and fraction 6 showed more similar spectrum patterns after TMS-derivatization than before. These results confirm presence of falcarinol in A. senticosus.

A Study on the Emulsifying Stability of W/O Type Sunscreen Cream by the Hansen Solubility Parameter (Hansen Solubility Parameter 를 통한 W/O 형 자외선차단 제형의 유화 안정성에 관한 연구)

  • Kim, Dong Hee;Lee, Jin Jae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.4
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    • pp.273-280
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    • 2021
  • The water resistance is important factor for sunscreen formulations. Generally a sunscreen cream was formulated by a water-in-oil (W/O) emulsion. In the W/O emulsion system, silicone oils are added to improve the texture of formulations. Silicone oils have low compatibility with organic sunscreen agent, causing problems with the stability in emulsion. In this study, the compatibility between various oils in the W/O emulsion was derived numerically using Hansen solubility parameter (HSP) at first. HSP is represented a dispersion degree, a polarity, and a hydrgen bond in a composition. In this study, various emulsions were prepared according to the types of oils with different HSP values and then monitored by a viscosity and morphology according to the time and temperature. The HSP values of components and the experimental results have similar activities for the stability of emulsions. HSP made it easy to select oil with high compatibility. When the compatibility of the oil phase in the W/O emulsion was high, the viscosity change over time was small. The stability was improved under the freeze-thaw cycle (-15 ℃ ~ 45 ℃). In the future, if the composition of the ingredients is optimized through HSP, it is expected that it will be helpful in the development of W/O type sunscreen formulations that are excellent in use and stability.

Food Components and Quality Characteristics of Boiled-Dried Anchovies Caught by Pound Net (죽방 마른멸치의 성분조성 및 품질)

  • 김종태;강수태;강정구;최동진;김석무;오광수
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.8
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    • pp.1186-1192
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    • 2003
  • The food components and quality characteristics of two kinds of boiled-dried anchovies (Engraulis japonica) in the Korean market such as the Jukbang-Myoel (JM) and Kwonhyunmang-Myeol (KM) were investigated. KM was higher in moisture content, and lower in crude protein and lipid contents than JM. Volatile basic nitrogen was higher in KM than in JM, whereas TBA value showed higher levels in JM. Total combined amino acid contents of KM and JM were 41.9∼46.6 g/100 g and 42.0∼49.2 g/100 g, respectively, and large sized boiled-dried anchovies revealed higher contents than small sized ones in both samples. Their major amino acids were Glu, Asp, His, Leu, Ala and Arg. Total lipids of KM and JM were consisted of 55.4 ∼ 68.4%, 53.0 ∼ 68.0% neutral lipid and 31.6∼44.6%,32.0∼47.0% polar lipid, respectively, and their major fatty acids were 14:0, 16:0, 16:1n-7, 18:1n-9, 20:5n-3 and 22:6n-3. In taste compounds of boiled-dried anchovies, free amino acid contents of Km and JM were 953.7 ∼ 1,044.8 mg/100 g and 968.8 ∼ 1,306.4 mg/100 g, respectively, and main free amino acids were Tau, His, Ala, 1-methyl his, Lys, Glu and Gly. The contents of other taste-active components such as IMP, total creatinine, TMAO and inorganic ions were not significantly different between KM and JM. The results of sensory evaluations for organoleptic characteristics, small sized JM showed no difference in sensory qualities, whereas large sized JM showed good qualities for appearance, taste and odor compared with KM.

Fine Structural Analysis of Principal and Secondary Eyes in Wandering Spider, Pardosa astrigera (배회성 거미 (Pardosa astrigera) 주안과 부안의 미세구조적 분석)

  • Jeong, Moon-Jin;Lim, Do-Seon;Moon, Myung-Jin
    • Applied Microscopy
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    • v.30 no.1
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    • pp.1-9
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    • 2000
  • The wandering spider, Pardosa astrigera, had four pairs of ocelli that arranged in three rows on the cephalothorax. Along the anterior margin lay a pair of small anterior median (AM) eye flanked on each side by anterior lateral (AL) eye. Two large posterior median (PM) eye was situated on the clypeus behind the anterior row and still more posteriorly was a pair of posterior lateral (PL) eye. The visual cell of retina consisted of cell body, rhabdome, and intermediate segment. Bipolar neuron was found in anterior median eye (principal eye) and unipolar neuron in others (secondary eye). Rhabdome showed that arranged in PMeye and PLeye. But rhabdomes of AMeye and ALeye were irregular in retina. Except AMeye, incontinuous tapetum found in ALeye, PMeye, PLeye. Anterior median eye was similar to anterior lateral eye in length and posterior median eye similar to posterior lateral eye. Component size of eye were similar to 4 pairs eye in cornea. Size of lens, cell body, and rhabdome was similar not only anterior median eye and anterior lateral eye but also posterior median eye and posterior lateral eye. Vitreous body was large posterior median eye than others.

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