• 제목/요약/키워드: Investigation of Origin

검색결과 242건 처리시간 0.025초

Recent Discovery of Bioactive Natural Products from Taiwanese Marine Invertebrates

  • Shen, Ya-Ching
    • 한국해양바이오학회지
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    • 제1권4호
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    • pp.225-231
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    • 2006
  • The secondary metabolites from Taiwanese marine soft corals and sponges have attracted much attention because they possess considerable potential biological activities. To explore the origin of bioactivity, many cytotoxic natural products were isolated and characterized in the past few years. For examples, The lipophilic extracts from marine sponges Petrosia elastica and Ircinia formosana were found active against several human tumor cells. The investigation of the gorgonian Junceela has also resulted in the discovery of a series of new juncenolides. Bioassay-directed fractionation of Clavularia viridis yielded seven new prostanoids. These compounds have been tested and evaluated as potential antitumor agents. The soft corals of the genus Cespitularia produced novel secondary metabolites with diverse chemical structures and interesting biological activities. Four new norditerpenoids, designated cespitulactones and cespihypotins were isolated from Cespitularia hypotentaculata. Cespitulactones are novel structures having a bond cleavage between C-10 and C-11. In addition, three novel diterpenes were isolated from C. taeniata and designated cespitulactams A, B and C having a phenylethyl amino side chain.

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한의학에서의 환자-의사 관계 (The Patient-Doctor Relationship in Eastern Medicine)

  • 김근우
    • 동의신경정신과학회지
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    • 제18권3호
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    • pp.97-112
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    • 2007
  • Objectives : This study aimed for desirable cure through the investigation of The Patient-Doctor Relationship in Eastern Medicine. Methods : Research materials is data of the patient the doctor and the Patient-Doctor Relationship in Eastern Medicine bibliography except medical theory and clinical contents. Results and Conclusion :. 1. Relatively the doctor's position origin from exorcist has it over patient's that. 2. In spite of clinical doctor, Confucian physician have Confucianism and the ethics so they set The Patient-Doctor Relationship in Eastern Medicine essentially. 3. Each of doctor(the doctor-doctor relationship) emphasize the partnership in the Patient-Doctor Relationship. 4. Patient's choice for doctor is source of the Patient-Doctor Relationship basically and the choice are prudent. 5. The patient must carry into practice psychological and body medical affairs related to health preserving 6. For desirable Patient-Doctor Relationship, doctor's inquire is considered with temper and circumstance and a consultation room are also required stability. 7. Poor Patient-Doctor Relationship are come about when patient is not trust doctor, patient is not follow doctor's order and doctor's indifference to patient.

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Linzhi Native Pig - An Investigation Report on New Genetic Resource of Livestock

  • Chang, H.;Mimachiren, Mimachiren;Li, X.Y.;Ren, Z.J.;Dongwang, Dongwang;Dejiyangzhong, Dejiyangzhong;Chang, G.B.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권9호
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    • pp.1203-1208
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    • 2001
  • Linzhi Native Pig is a unique local breed recently discovered in the hinterland of Tibet. Its geological distribution, natural environment and ecological conditions have been explored. Using random sampling in typical colony of classification and standard animal-scientific and biogenetic techniques, we examined its contour features, size and weight, reproductive performances, carcass characters, meat quality, fresh-keeping features and the frequency distribution in the 19 structural gene loci encoding enzymes and proteins; according to folklores and Tibetan, Chinese and English history books, the materials and literature of Tibetan Studies, we have analyzed its origin and affirmed the fact that its products have been consumed as Tibetan medicine resources. Our findings make certain that Linzhi Native Pig holds great potential value in economy and culture.

TEM Stud of GaN Thick Film Crystals Grown by HVPE

  • 송세안;이성국
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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    • pp.121-121
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    • 1999
  • Gallium nitride (GaN) semiconductor is intensively under investigation for commercialization of short wavelength light emitting devices and laser diodes. One of serious obstacles to overcome is to reduce the defect density in GaN film grown by various techniques such as MOCVD, HVPE, etc. Many research groups including SAIT are trying to improve the defect density to 106-107/cm2 from the level of 108-1010/cm2. We have investigated epitaxial growth behaviour of GaN thin and thick films under hidride vapour phase epitaxy (HVPE) condition. In this report, we present the microstructural and crystallographical characteristics of the GaN films grown on sapphire (0001) substrate which were studied by both conventional and high-resolution transmission electron microscopy (TEM). Also we present some microscopic analysis results obtained from GaN films grown by ELO(dpitzsial lateral overgrowth)-HVPE and from GaN quantum well structures grown by MOCVD. Another serious problem in growing GaN thick film by HVPE is internal micro-cracks. We also comment the origin of the micro-crack.

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Shell Candidates from I-GALFA HI Survey

  • Park, Geum-Sook;Koo, Bon-Chul
    • 천문학회보
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    • 제35권2호
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    • pp.68.2-68.2
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    • 2010
  • Diffuse interstellar atomic hydrogen (HI) gases are easily shaped into shell-like features by energetic processes such as stellar winds and supernova explosions. The physical characteristics and the Galactic distribution of HI shells and shell-like structures, therefore, are closely related to those of the energy sources. Recently, Inner-Galaxy Arecibo L-band Feed Array (I-GALFA) low-latitude HI survey has been completed. I-GALFA HI survey covers the central part of the first quadrant ($31^{\circ}{\lesssim}1{\lesssim}77^{\circ}$ at b = $0^{\circ}$, ${\mid}b{\mid}\lesssim\;12^{\circ}$) with spatial and velocity resolutions of 3.35′and 0.184 km/s, respectively. The high-angular and high-velocity resolutions enable in-depth investigation of HI shells including the ones of smaller angular sizes. We have found 36 shell candidates with the naked eye. Their angular sizes are distributed from $\sim0.4^{\circ}$ to $\sim12^{\circ}$. About sixteen of them appear to be expanding. We examine associated features at other wavebands and discuss their origin.

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환경물리탐사 기법을 이용한 유류오염 주유소 부지 특성 조사

  • 김창렬;고경석;김정호;박삼규;손정술;정지민
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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    • pp.429-432
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    • 2005
  • Geophysical investigations, as a non-invasive method, were conducted at the former gas station site contaminated with fuel hydrocarbons. GPR (Ground Penetrating Radar) survey was performed to locate buried objects such as USTs (Underground Storage Tanks) and fuel pipes which might serve as a origin of the site contamination. Additional GPR investigation and a resistivity survey were conducted to map water table and to characterize shallow geologic structures of the site. The results of the study have shown that seven USTs including one unknown UST and buried fuel pipes are present, and that the groundwater elevation varies with topography from approximately 1.5 to 3m below the surface and the water table is located in the residual soils above the bedrock in the site. The results also show that the geophysical methods can be a very useful tool for the characterization of the contaminated site.

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탐지문턱값 적응기법을 이용한 표적추적 유효화 영역의 최적화 (Optimization of the Validation Region for Target Tracking Using an Adaptive Detection Threshold)

  • 최성린;김용식;홍금식
    • 한국항공우주학회지
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    • 제30권2호
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    • pp.75-82
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    • 2002
  • 불확실한 측정값 근원의 문제에서는 표적을 최적으로 탐지해내는 것이 유용하다. 본 논문에서는 클러터 환경에서 표적을 추적하는 경우에 탐지확률 및 오경보확률과 동시에 탐지문턱값 처리에 따른 추적오차를 살펴보고, 문턱값과 표적추적 유효화영역의 최적화 알고리즘을 제안한다. 제안한 알고리즘은 시뮬레이션을 통해 상태추정오차공분산의 측면에서 성능을 분석한다.

표면 분석을 이용한 컴퓨터 하드디스크용 윤활제의 특성 연구 (Investigation of the Characteristics of Lubricant in Computer Hard Disk by Using Surface Analysis Technique)

  • 조남철;남인탁
    • 한국자기학회지
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    • 제9권5호
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    • pp.263-270
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    • 1999
  • 컴퓨터 하드디스크용 윤활제인 PFPE중 Z-DOL과 AM2001을 이용하여 pulling-up speed와 윤활제의 농도를 변화시키면서 윤활제의 두께변화를 알아보았으며, 또한 열처리를 통해 overcoat층인 carbon과 윤활제의 결합특성을 알아보았다. Pulling-up speed가 빠를수록, 그리고 윤활제의 농도가 증가할수록 윤활제의 두께는 두껍게 coating되었음을 알 수 있었으며, 또한 XPS을 이용하여 분석해 본 결과, overcoat층인 carbon에 존재하는 표면 오염물은 C-OH, CO가 지배적이었고, 열처리를 함으로써 overcoat층인 carbon과 윤활제의 결합력이 증진됨을 알 수 있었다.

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Investigation of Dark Spots Occurred in Plastic LCDs.

  • Park, Seo-Kyu;Min, Kwan-Sik;Choi, Man-Seob;Im, Jang-Soon;Woo, Sung-Il;Kwon, Soon-Bum
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.524-527
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    • 2003
  • Plastic LCDs have remarkable advantages as compared to glass LCDs, but there still exist reliability issue. Regarding the reliability issue of plastic LCDs, we investigated the phenomena of dark spots that often occurred in plastic LCDs. It was recognized that dark spots are mainly caused by air bubbles that are induced from outside of LCD panel due to cell volume change with external stress and incomplete encapsulation. We have found that cell gap uniformity, spacer density and size and film deformation are important factors influencing dark spot behavior. In this paper, we discuss the phenomena and origin of dark spots in plastic LCDs

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차량화재 사고경향 및 사례분석 (Latest passenger vehicle fire trend and case study based on field investigation data)

  • 신준호;원유진;홍일민
    • 자동차안전학회지
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    • 제6권2호
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    • pp.67-71
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    • 2014
  • Based on the analysis of the actual passenger vehicle fire cases for recent four years (2010~2013), the passenger vehicle fire is increasing annually. Main root cause was analyzed as an electric problem as a 39%. Vehicle fire case by electric problem was mainly caused by use of Non-genuine part. Vehicle fire case by mechanical problem was mainly caused by various oil system maintenance. Vehicle fire case by smoking material was mainly caused by cigarette and disposal lighter. And external fire transition issue and towing mistake fire cases was also confirmed.