• 제목/요약/키워드: C-SCI

검색결과 684건 처리시간 0.027초

스퍼터링 방법을 이용한 중금속 산화물 유리 박막의 증착 (Deposition of Heavy Metal Oxide Glass Thin Films by R.F. Magnetron Sputtering)

  • 김웅권;허종;제정호
    • 한국세라믹학회지
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    • 제32권6호
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    • pp.669-676
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    • 1995
  • In this study, EO glass films were deposited by R.F. magnetron sputtering using EO glass target. The glass formation of the EO film was greatly dependent on the substrate temperature and the crystallization started at approximately 28$0^{\circ}C$. As the temperature of the substrate or the oxygen content in the sputtering gas increased, UV/VIS/NIR absorption edge moved toward longer wavelength. A wave guiding phenomenon was observed from the prism-coupler experiment and a fluorescence of 1.06${\mu}{\textrm}{m}$ originated from 4Fe3/2longrightarrow4I11/2 transition of Nd3+ was detected from the film containing Nd3+ ions.

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Properties of Combustion Synthesized $SnO_2:Eu^{3+}$ Phosphors

  • Kang, Jong-Hyuk;Kim, Jin-Young;Jeon, Duk-Young
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.831-834
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    • 2002
  • A novel ceramic synthesis technique, combustion synthesis, is explored to produce an orange-emitting $SnO_2:Eu^{3+}$ phosphors. This technique involves a reaction of metal salts with a citric acid as an organic fuel. The variation of the ratio of citric acid to metal introduces change in reaction temperature and atmosphere of the combustion reaction, which in turn influences crystallinity and luminescence properties of the final products significantly. And the heat treatment of the as-synthesized product improved the CL intensity of the products. Especially, the sample treated at above 1100 $^{\circ}C$ shows an orange-emission, which is attributed to the formation of single phase and well-crystallized $SnO_2$:Eu in rutile structure.

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Magnetization Processes in Partially Crystallized Co-Based Metallic Glass

  • Lachowicz, H.K.;Poplawsi, F.;Zuberek, R.;Kuzminski, M.;Slawska-Waniewska, A.;Dynowska, E.;Yu, S.C.
    • Journal of Magnetics
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    • 제4권3호
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    • pp.84-87
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    • 1999
  • It is shown that progressive crystallization of non-magnetostrictive Co-based metallic glass (VITROVAC 6030) leads to an increase of coercivity by more than three orders of magnitude. The mechani는 responsible for this phenomenon are interpreted showing that the main source for the giant increase of the coercivity is the pinning effect on the domain walls originating from the created crystallites of the size much smaller than the domain width (correlation length for ferromagnetic exchange interactions). It is also shown that gradually devitrified non-magnetostrictive metallic glass is an excellent model material for verification of N el's theory describing the Rayleigh rule.

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ROMP를 이용한 희소 표현 방식 얼굴 인식 방법론 (Face Recognition via Sparse Representation using the ROMP Method)

  • 안정호;최권택
    • 디지털콘텐츠학회 논문지
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    • 제18권2호
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    • pp.347-356
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    • 2017
  • 희소 표현을 이용한 얼굴 인식 방법론은 강인성이 입증된 우수한 얼굴 인식 방법으로 알려져 있다. 이 방법론의 단점은 $L_1$-노름 최적화 문제를 통해 희소해를 구하는 과정에서 많은 시간이 소요되어 실시간 응용 분야에 적합하지 않다는 것이다. 통상적인 $L_2$-노름 최적화 문제를 통해 얻어진 희소해는 희소성이 결여되고 정확도가 떨어져서 희소 표현을 이용한 인식 방법론에는 사용되고 있지 않다. 우리는 본 논문에서는 탐욕적인 방식으로 $L_2$-노름 최적화 문제를 푸는 ROMP 방식을 도입해 희소해를 구하는 방법을 제안하고, 실험을 통해 제안한 방식이 정확도에서 기존 방식과 유사하며 속도는 60배 이상 빠름을 보였다. 또한, 희소 표현기반인식 방법론으로 희소해의 분포만을 고려하여 분류하는 단순한 방식인 C-SCI 방법론을 제안하였다. 이 방법론은 테스트 데이터를 복원하는 기존 방식과 성능 면에서는 유사하나 속도 면에서는 약 5배 빠름을 실험적으로 입증하였고, 이론적인 복잡도 분석 결과도 제시하였다.

Comparative Studies on Velvet Deer Antler and Ossified Deer Antler on the Contents of Bioactive Components and on the Bone Mineral Density Improving Activity for Oophorectomized Rat

  • Jo, Sung Jun;Kim, Jung Hwan;Kim, Jeung-Won;Choi, Hye Ok;Lee, Seung Hwan;Kim, Mu-Kang;Woo, Sun Hee;Han, Byung Hoon
    • Natural Product Sciences
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    • 제19권4호
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    • pp.303-310
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    • 2013
  • Velvet deer antler (VDA) is well known oriental medicine claimed to have tonic activities as improving bone mineral density (BMD), immune-enhancing, rejuvenating and many other medicinal activities. Ossified deer antler (ODA) is bony product produced by over-calcification of deer antler due to late harvesting. The extraction efficiency of ODA by conventional boiling in water must be very poor due to bony nature, hence the reputations for the medicinal efficacies of ODA has been highly under-evaluated compared to that of VDA without any experimental evidences. Employing our new efficient water extraction process ($135^{\circ}C$), the extracts of ODA and VDA were analysed to compare the contents of bioactive components and the potencies of pharmacological activities. The results showed that; 1) The $135^{\circ}C$ extraction (autoclaving) of ODA gave highly increased amount of biomass, 120% more than the conventional extraction by 100-boiling, whereas the same treatment for VDA showed only 15% increased amount of biomass. 2) Feeding the ODA- or VDA-extracts to oophorectomized rats showed very potent BMD-recovering activity. 3) During the ossification of deer antler, the total collagen content was found to be increased by addition of type-1 to pre-existing type-2 collagen, but not replacement of type-2 to type-1 collagen. High titer of peptide hormones like growth hormone and IGF-1 were detected in the ODA- and VDA-extracts and also in the serum of ODA- or VDA-treated oophorectomized animals dose-dependently. Present experimental data will give a conclusion that folkloric poor reputations on ODA must be concerned only with poor extraction efficiency of conventional $100^{\circ}C$ water extraction and not based on the composition of bioactive substances of ODA.

Analgesic Effects of Transcranial Direct Current Stimulation on Central Neuropathic Pain in Spinal Cord Contusive Rat Model

  • Kim, Kyung-Yoon;Sim, Ki-Chol;Kim, Hyun-Seung;Choi, Wan-Suk;Kim, Gi-Do
    • International Journal of Contents
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    • 제8권1호
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    • pp.74-81
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    • 2012
  • The aim is to investigate the analgesic effect of transcranial direct current stimulation(tDCS) on central neuropathic pain(CNP) in spinal cord contusive rat model. Twenty Sprague-Dawley rats($250{\pm}50$ g, male) were used. Thoracic spinal cord(T10) was contused using New York University(NYU) spinal cord impactor. The animals were randomly assigned to two groups; GroupI: Non-treatment after SCI induction(n=10), GroupII: application of tDCS(0.1 mA, 20 min/time, 2 times/day, 5 days/6week) after SCI induction(n=10). Assess the effect of tDCS using the Basso Beattie Bresnahan(BBB) locomotor rating scales, Touch $test^{TM}$ sensory evaluator(TTSE), Plantar test$^{\circledR}$after contusion at the $2^{nd}$, $3^{rd}$, $4^{th}$, $5^{th}$, $6^{th}$ week and the immunohistochemistric response of c-fos in the thalamus, cerebral cortex after contusion at the $3^{rd}$, $6^{th}$ week after SCI. The scores of BBB scales were significantly different from $3^{rd}$week. TTSE were different significantly over time, but there were no differences at each evaluation times on between-measure time effects. Plantar test were different significantly over time and there were difference at the $4^{th}$, $6^{th}$ week after SCI on between-measure time effects. Also, immunohistochemistric response of c-fos was reduced significantly from $3^{rd}$, $6^{th}$ week after SCI in tDCS group compared with control group in thalamus and cortex. These results identified that tDCS of non-invasive therapeutic method may have beneficial analgesic effect on CNP after SCI with behavioral test and immunohistochemical test.

산과 열처리에 따른 마늘 Fructan과 항산화활성 변화 (Change in Fructan Content and Antioxidant Activity of Garlic Treated Acid and Heat)

  • 황인국;김기찬;최성길;이준수;정헌상
    • 농업생명과학연구
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    • 제44권1호
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    • pp.61-67
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    • 2010
  • 마늘의 주요 저장성분인 fructan을 산 가수분해시키고 열처리에 따른 폴리페놀함량과 항산화활성의 변화를 살펴보았다. 마늘 fructan의 최적 산가수분해 조건은 0.3N $H_2SO_4$으로 5분간 반응시켰을 때로 나타났다. 열처리에 의한 fructan 함량은 열처리 온도가 증가함에 따라 240.5 mg/g에서 2.0 mg/g으로 분해되어 감소하였으며, 총 폴리페놀 함량은 열처리 온도 증가에 따라 0.85 mg/g에서 13.74 mg/g으로 증가하였고, 항산화활성($IC_{50}$)은 열처리온도가 증가에 따라 52.9 mg/mL에서 1.5 mg/mL으로 증가하였다. 열처리 후 산가수분해시 총 폴리페놀 함량 및 항산화활성은 증가하였다. 마늘 fructan을 분해하여 식품소재로서의 활용과 동시에 항산화활성을 강화시키기 위한 열처리 조건으로는 $130^{\circ}C$, 2시간 처리가 적합한 것으로 판단되었다.

온도(溫度)와 생장조절물질(生長調節物質)이 무궁화(Hibiscus syriacus ''Honghwarang') 삽수의 맹아(萌芽)에 미치는 영향 (Effects of Temperature and Plant Growth Regulators on Bud Sprouting of Stem Cutting of Hibiscus syriacus 'Honghwarang')

  • 백이화;조근호;박천호;허무룡;곽병화
    • 원예과학기술지
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    • 제16권3호
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    • pp.355-357
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    • 1998
  • 무궁화 (Hibiscus syriacus 'Honghwarang')의 휴면특성을 구명하고자 온도와 생장조절물질을 처리하여 맹아(萌芽) 차이를 비교하였다. 맹아는 온도가 높을수록 빨랐으며($10{\sim}30^{\circ}C$), $30^{\circ}C$ 무처리구는 삽목 후 4일만에 맹아하기 시작하여 6일경에는 100% 맹아했다. GA와 BA처리도 대조구인 무처리와 큰 차이 없이 $20^{\circ}C$ 이상의 온도에서는 6일만에 맹아하여 62.5%의 높은 맹아율을 나타내었다. ABA 침지처리는 $25^{\circ}C$이하의 온도에서는 맹아율이 저조하였으나, $25^{\circ}C$이상의 온도에서는 삽목 6일 후에 맹아하기 시작하여 12일 후에 93% 맹아되어, 고온 조건에서는 생장억제제인 ABA처리가 맹아억제에 전혀 효과가 없었다.

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