• 제목/요약/키워드: N.D.C method

검색결과 792건 처리시간 0.041초

Ni-W 기판 위에 동시증발법으로 제조한 SmBCO 초전도선재 (SmBCO superconducting tape fabricated using co-evaporation method on Ni-W substrate)

  • 오상수;김호섭;하홍수;고락길;송규정;하동우;이남진;양주생;김태형;정예현;염도준
    • 한국초전도ㆍ저온공학회논문지
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    • 제8권3호
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    • pp.9-12
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    • 2006
  • Batch type co-evaporation EDDC (Evaporation using Drum in Dual Chambers) system was recently manufactured to fabricate 100m - long SmBCO superconducting coated conductor. As a preliminary study before the fabrication of long tape. short CC samples have been fabricated using the EDDC system and their crystal texture and $I_c$ properties were investigated. $1.2 {\mu}m$-thick SmBCO layers were deposited on $CeO_2/YSZ/CeO_2$ buffered Ni-W tapes. $I_c$ of 128A/cm-w and corresponding $J_c$ of $1.1 MA/cm^2$ at 77K in self-field were obtained for SmBCO CC tape. In-field property of SmBCO CC was confirmed to be better than that of YBCO deposited by PLD.

조성비에 따른 (1-x)(Na,K)$NbO_3$-xBa(Zr,Ti)$O_3$ 세라믹스의 압전 특성 (Piezoelectric properties of (1-x)(Na,K)$NbO_3$-xBa(Zr,Ti)$O_3$ ceramics with composition)

  • 이영희;이동현;배선기;이상철;최달해
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2011년도 제42회 하계학술대회
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    • pp.1436-1437
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    • 2011
  • (1-x)(Na,K)$NbO_3$-xBa(Zr,Ti)$O_3$ lead free piezoelectric ceramics were synthesized to enhance the piezoelectric properties of (Na,K)$NbO_3$. The synthesis and sintering method were the conventional solid state reaction method and general sintering method in air atmosphere. We report the improved piezoelectric properties in the perovskite structure composed of the NKN and BZT ceramics. We investigated the effects of NKN, BZT on the structural and electrical properties of the NKN-BZT ceramics. The NKN-BZT ceramics show good performance with piezoelectric constant $d_{33}$=155pC/N. The results reveal that (1-x)(Na,K)$NbO_3$-xBa(Zr,Ti)$O_3$ ceramics are promising candidate materials for lead-free piezoelectric application.

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동시 열증착법에 의한 $CdS_{1-x}Te_{1-x}$ 삼원계 다결정 박막의 제작과 특성 (Preparation and Characteristics of $CdS_{1-x}Te_{1-x}$ Ternary Polycrystalline Thin Films by Co-evaporation)

  • 박민서;송복식;정성훈;문동찬;김선태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.126-130
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    • 1995
  • $CdS_{1-x}Te_{1-x}$ polycrystalline thin films were fabricated from CdS and CdTe powder by co-evaporation method at $10^{-6}$ Torr. The Optimum evaporation condition was substrate temperature $T_{s}$=$150^{\circ}C$, evaporation time t=30 min. XRD spectrums indicated that the crystal structure chanced from zinc blonde (x$\leq$0.22) to wurtzite (x$\geq$0.96) through mixed structure (0.22$\leq$0.74) as composition value x increase to CdS. Conductive type was n-type by hot point probe method. van der Pauw method was not applicable for x<0,5 due to high hall voltages, Electrical resistivity and Hall carrier mobility were decreased as x increase, while Hall carrier concentration was increased. The optical bandgap of $CdS_{1-x}Te_{1-x}$ polycrystalline thin films measure d at R.T. had quardratic form and the bowing parameter was fitted as 1.98eV for theoretical value of 2.0eV. I-V characteristics of In/CdTe/$CdS_{x}Te_{1-x}$Au Schottky diodes showed that CdS-rich one had better forward characteristics than CdTe-rich one.

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다구찌 방법에 의한 PAC 실내기 유로의 최적설계 (Optimum Design of an Indoor Package Air-Conditioner's Flow Path by Taguchi Method)

  • 김장권;오석형
    • 동력기계공학회지
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    • 제18권1호
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    • pp.32-37
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    • 2014
  • In this study, the optimum design process of an indoor package air-conditioner (PAC) was implemented by Taguchi method. The goal of this study is to obtain the best set condition of each control factor composing of an indoor PAC. The number of revolution of a double inlet sirocco fan installed in an indoor PAC was measured by the orthogonal array of $L_{18}(2^3{\times}3^4)$ and analysed by using the-smaller- the-better characteristic among the static characteristic analyses. As a result, the optimum condition of an indoor PAC was found as a set of when the cost of production, assembling and working conditions were considered. Moreover, the number of revolution of a double-inlet sirocco fan used for an optimum condition was reduced about 8.5% more than that of a standard condition for the target flowrate of $18.5m^3/min$.

통증(痛症)의 한방치료(韓方治療)에 관(關)한 소고(小考) (A Study on the treatment of pain in oriental medicine)

  • 류경주
    • 한국한의학연구원논문집
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    • 제2권1호
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    • pp.454-484
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    • 1996
  • There are many factors to evoke pain, for example cold, heat, seven emotion, digestion, fatigue, venemous worms, deficiency of blood etc., and its pathogenesis is complicated. Treatments for pain in oriental medicine are as follows. 1. Pharmacotherapy is a method to treat pain by different effects of herbal medicine, for example, regulating vital energy, activating blood circulation, eliminating phlegm, and dispelling the cold evil etc. 2. Acupuncture and moxibustion therapy is a kind of external application, it has a distinct effect in relieving pain. Recently its operation method has been more developed, so new acupuncture therapies are used in clinics. There are electroacupuncture, auricular acupuncture and injection of drugs at an acupuncture points etc. 3. Oriental physiotherapy is a treatment method to stimulate acupuncture points and meridians. (1) Hot pack, Paraffin bath, Microwave, Ultrasound, Short wave, Infra-red etc. are used to treat cold syndrome by dispersing cold by warming the channels. (2) E.S.T., I.C.T., T.E.N.S., S.S.P., cupping treatment etc. are used to treat disorders of vital energy. (3) Health ion, Carbon, T.D.P., etc are used to treat conic and deficiency syndrome.

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Advanced Method for Determination of Omeprazole in Plasma by HPLC

  • Kang, Won-Ku;Kim, Dong-Sup;Kwon, Dwang-Il
    • Archives of Pharmacal Research
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    • 제22권1호
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    • pp.86-88
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    • 1999
  • An advance d and sensitive high-performance liquid chromatographic (HPLC) method for determination of omeparzole in human plasma has been developed. After omeprazole was extracted from plasma with diethylether, the organic phase was transferred to another tube and trapped back with 0.1 N NaOH solution. The alkaline aqueous layer was injected into a reversed-phase C8 column. Lansoprazole was used as an internal standard. The mobile phase consisted of 30% of acetonitrile and 70% of 0.2 M $ KH_{2}PO_{4}$, pH 7.0. Recoveries of the analytes and internal standard were >75.48%. The coefficients of variation of intra- and inter-day assay were <5.78 and 4.59% for plasma samples. The detection limit in plasma was 2 ng/ml. The clinical applicability of this assay method was evaluated by determining plasma concentration-time courses of the respective analytes in 24 healthy volunteers after oral administration 40 mg of omeprazole. The present assay is considered to be simple, accurate, economical and suitable for the study of the kinetic disposition of omeprazole in the body.

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곡류 및 버섯류의 평형함수율 및 박층건조방정식에 관한 연구(II) - 표고버섯에 대하여 - (Equilibrium Moisture Contents and Thin Layer Drying Equations of Cereal Grains and Mushrooms (II) - for Oak Mushroom (Lentinus erodes) -)

  • 금동혁;김훈;홍남운
    • Journal of Biosystems Engineering
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    • 제27권3호
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    • pp.219-226
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    • 2002
  • Desorption equilibrium moisture contents of oak mushroom were measured by the static method using salt solutions at flour temperature levels of 35$\^{C}$, 45$\^{C}$, 55$\^{C}$ and 6$\^{C}$ and five relative humidity levels in the range from 11.0% to 90.8%. EMC data were fitted to the modified Henderson, Chung-Pfost, modified Halsey and modified Oswin models using nonlinear regression analysis. Drying tests far oak mushroom were conducted in an experimental dryer equipped with air conditioning unit. The drying test were performed in triplicate at flour air temperatures of 35$\^{C}$, 45$\^{C}$, 55$\^{C}$ and 65$\^{C}$ and three relative humidities of 30%, 50% and 70% respectively. Measured moisture ratio data were fitted to the selected four drying models(Lewis, Page, simplified diffusion and Thompson models) using stepwise multiple regression analysis. The results of comparing root mean square errors for EMC models showed that modified Halsey was the best model, and modified Oswin models could be available far oak mushroom. The results of comparing coefficients of determination and root mean square errors of moisture ratio for four drying models showed that Page model were found to fit adequately to all drying test data with a coefficient of determination of 0.9990 and root mean square error of moisture ratio of 0.00739.

Null 부반송파를 갖는 MIMO-OFDM에서 채널 예측 기반적응 채널 추적 방식 (Channel Prediction based Adaptive Channel Tracking cheme in MIMO-OFDM Systems with Null Sub-carriers)

  • 전형구
    • 한국통신학회논문지
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    • 제32권5C호
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    • pp.556-564
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    • 2007
  • 본 논문에서는 다중 채널 레이리 페이딩으로 인하여 발생하는 시변 채널 환경에서 효율적으로 채널을 추적할 수 있는 방식을 제안하였다. 제안된 적응 채널 추적 방식은 채널 변화를 추정하여 채널을 예측할 수 있으며 예측된 채널 응답을 이용하여 주파수 영역에서 다른 안테나로부터 수신되는 간섭 신호를 제거한다. 그 후 AWGN 성분을 줄이기 위하여 시간영역 채널 추정을 수행한다. 제안된 방식의 장점은 매 심벌 마다 채널 추적시 역행렬을 구할 필요가 없다. 시뮬레이션 결과는 기존의 채널 추적 방식보다 시변 채널 환경에서 더 나은 성능을 보였다. 도플러 주파수 300 Hz, BER = 10-3 조건에서 기존의 Li 방식 보다 약 2.5 dB 성능이 개선되었다. 도플러 주파수 600 Hz에서 기존 방식과 제안된 방식의 성능 차이는 더욱 커졌다.

김에서 Porphyran의 효율적 추출 방법 및 Porphyran 잼 제조연구 (Study on Manufactute of Porphyran Jam and Eppiciency Extraction Method of Porphyran from Porphyra yezoensis)

  • 류성렬
    • 한국응용과학기술학회지
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    • 제30권3호
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    • pp.504-517
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    • 2013
  • The purpose of this study was to process extraction and separation for polyglucose porpyran from pophyra yezoensis as high yield. The acidic porphyran solution was extracted with 0.1~1N of ${\alpha},{\beta}$-dichloromaleic acid or ${\alpha}$-chloromaleic acid of 2% solution as organic acid instead of inorganic acid at $60^{\circ}C$ and then porphyran was collection of high yield to acidic solution and it was neutralization treated with 0.1N of $d-Ca(OH)_2$ solution and the mixture was conversion to porphyran salt form and treated with a shell powder of ouster and then added of ethanol as precipitator. It recovery porphyran contained of violet purple laver coloring matter was obtained as a crystalline and used for the next step without future purification to prepare of porphyran laver jam. so, The resulting porphyran and porphyran jam was characterized by it component and physical properties.

$Cd_{4}GeS_{6}$$Cd_{4}GeS_{6}:Co^{2+}$ 단결정의 성장 (Crystal Growth of Cd4GeS6 and Cd4GeS6:Co2+Single Crystals)

  • 김덕태;김형곤;김남오
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집
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    • pp.1-6
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    • 2004
  • In this paper author describe the undoped and $Co^{2+}$ (0.5mole%)doped $Cd_4GeS_6$ single crystals were grown by the chemical transporting reaction(CTR) method using high purity(6N) Cd, $GeS_2$, S elements. It was found from the analysis of X-ray diffraction that the undoped and $Co^{2+}$(0.5mole%) doped $Cd_{4}GeS_{6}$ compounds have a monoclinic structure in space grop Cc. The optical energy band gap was direct band gap and temperature dependence of optical energy gap was fitted well to Varshni equation. Impurity optical absorption peaks due to the doped cobalt in the $Cd_4GeS_6:Co^{2+}$ single crystal were observed at 3593cm-1, 5048cm-1, 5901cm-1, 7322cm-1, 12834cm-1, 13250cm-1, 14250cm-1,and 14975cm-1 at 11.3K.

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