• 제목/요약/키워드: induced- index change

검색결과 167건 처리시간 0.032초

Field-induced refractive index variations in GaAs/AlGaAs multiple quantum well waveguide modulator

  • Cho, Wook-Rae;Park, Seung-Han;Kim, Ung;Park, Kyung-Hyun
    • Journal of the Optical Society of Korea
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    • 제1권1호
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    • pp.48-51
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    • 1997
  • A quantum well electroabsorption waveguide modulator utilizing a field-induced refractive index change was designed and fabricated. The on/off ratios of the device were investigated as a function of wavelength over the spectral range of 850 nm to 910 nm for the various reverse biases. The field-induced refractive index variations associated with quantum-confined Stark effect was theoretically obtained based on the measured on/off ratios. The resulting maximum refractive index change(${\DELTA}n) of ~7.5 {\times} 10^{-4}$ at -8 V was estimated.

수술적 폐경을 경험한 여성과 자연 폐경 된 여성의 Kupperman's Index, MENQOL 비교 (The Comparison of Kupperman's Index and MENQOL between Women with Surgical Menopause and Women with Natural Menopause)

  • 박은영;박영선;공복철;김동철
    • 대한한방부인과학회지
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    • 제24권4호
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    • pp.150-162
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    • 2011
  • Purpose: To investigate the change of the climacteric syndrome with women with induced menopause by hysterectomy or ovariectomy compared with women with natural menopause. Methods: Menopausal women(aged 45-55) were selected at two oriental medicine hospitals, Sam-se Oriental Medicine Hospital and Daegu Hannny Oriental Medicine Hospital. They were asked about Kupperman's Index, MENQOL and a few additional questions. They were divided into two groups: women with induced menopause by hysterectomy or ovariectomy and women with natural menopause. To analyse the Kupperman's index and MENQOL, SPSS for Windows 12.0 and Wilcoxon Ranked Sum Test were used. Results: The total sums of Kupperman's index and MENQOL were significantly correlated with women with induced menopause and women with natural menopause and women with induced menopause had higher total sums. Both the renal and urinary tract disorder and the sexual disorder were significantly correlated with women with induced menopause and women with natural menopause. The gastrointestinal and psychosocial disorder of Kupperman's index and MENQOL were not significantly correlated with women with induced menopause and women with natural menopause. Conclusions: Women with induced menopause by hysterectomy or ovariectomy experienced climacteric syndrome more severely compared with women with natural menopause, specifically the renal and urinary tract disorder and sexual disorder.

견의 황변억제에 관한 연구 - 메탄올 및 희박염산처리에 의한 견피브로인의 내부구조전이가 황변억제에 미치는 영향 - (The Structural Changes in Silk Fibroin Induced by Methanol and Dilute Hydrochloric Acid and Its Photo yellowing Reduction Effect)

  • 장정대
    • 한국의류산업학회지
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    • 제4권2호
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    • pp.198-202
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    • 2002
  • Degummed silk from Bombyx mori was dissolved in 9.3M lithium bromide solution. The regenerated silk fibroin films were completely ${\alpha}$-randomcoil type as shown by x-ray diffraction and infrared spectroscopy. The structural changes in silk fibroin induced by immersion into methanol and dilute hydrochloric acid and its photo-yellowing effect was studied. The changes of crystallinity were measured by infrared spectrometer. Yellowness index caused by ultraviolet irradiation were observed as a function of the structural change on silk fibroin. On treatment with methanol, ${\alpha}$-randomcoil silk film is converted to the ${\beta}$-form structure. After the treatment of hydrochloric acid on ${\beta}$-form structure in silk induced by immersion into methanol, ${\beta}$-form in silk fibroin is partially decreased. Crystallization owing to ${\beta}$-form transition reduced the initial yellowness index by ultraviolet irradiation. A little ${\beta}$-form structure in silk fibroin increased the initial yellowness in comparison with more ${\beta}$-form structure.

광섬유-평면도파로 결합기를 이용한 광변색성 디아릴에텐 유도체의 광유도 굴절률 변화에 관한 연구 (Study on the photo-induced refractive index change of diarylethene derivative using fiber-to-planar waveguide coupler)

  • 조강민;윤정현;임선정;박수영;강신원
    • 한국광학회지
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    • 제15권2호
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    • pp.109-113
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    • 2004
  • 광섬유와 평면도파로 결합기의 소산장 결합을 이용하여 디아릴에텐 유도체 DM-BTE(1,2-bis[2,5-dimethylthio-phen-3-yl]-hexafluorocyclopentene)의 광유도 굴절률 변화(photo-induced refractive index change)에 관하여 그 특성을 평가하였다. DM-BTE가 분산된 평면도 파로는 자외선과 가시광선(λ>450 nm)의 조사에 의해 광변색 반응이 가역적으로 진행되었으며 굴절률변화에 의한 공명 파장 또한 가역적으로 이동하였다. 광변색 반응이 진행되는 동안 평면도 파로의 결정상태(crystal shape)는 일정한 형태를 유지하였으며, 자외선 조사시간에 대한 소자의 파장응답은 0.057 nm/sec 이었고 포화시간은 60 sec로 나타났으며, 가시광선이 다시 조사될 때의 공명파장의 변화는 0.028 nm/sec 이었고, 복귀시간은 140 sec로 측정되었다.

Antiulcer Activity of Sida acuta Burm.

  • Malairajan, P.;Gopalakrishnan, Geetha;Narasimhan, S.;Veni, K. Jessi Kala
    • Natural Product Sciences
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    • 제12권3호
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    • pp.150-152
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    • 2006
  • The ethanol extract of Sida acuta Burm. (ALSA) whole plant was studied for its anti-ulcer activity against aspirin plus pylorous ligation induced gastric ulcer, HCl-ethanol induced ulcer, and water immersion stress induced ulcer (WISIU) in rats. We found that ALSA at a dose of 300 mg/kg, (orally) markedly decrease the incidence of ulcers in the first two models. ALSA showed reduction in gastric volume, free acidity, and ulcer index (53.69%). It has not reduced the total acidity significantly and no significant change in pH. It also showed 55.14% gastro protective activity, wheres standard drug sucralfate showed 94.85%. WISIU showed protection index 24.4%, whereas standard drug omeprazole (OMEZ) showed protection index 100%.

Fabrication of Internal Gratings in PDMS Using a Femtosecond Laser

  • Park, Jung-Kyu;Cho, Sung-Hak;Yu, Jae-Yong;Kim, Jae-Gu;Sugioka, Koji;Hong, Jong-Wook;Heo, Won-Ha;Hwang, Kyung-Hyun
    • 한국레이저가공학회지
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    • 제14권1호
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    • pp.1-5
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    • 2011
  • Photo-induced gratings m flexible PDMS (polydimethly siloxane) film are directly written by a high-intensity femtosecond (130fs) Ti: Sapphire laser (${\lambda}_p$ = 800nm). The refractive index modifications with $4\;{\mu}m$ diameters were photo-induced after the femtosecond irradiation with peak intensities of more than $1{\times}10^{11}W/cm^2$. The graded refractive index profile was fabricated to be a symmetric around the center of the point at which femtosecond laser by controlling both laser power and focused depth. The change on refractive index in the laser-modified regions was estimated to be approximately $10^{-3}$. The internal flexible symmetric diffraction gratings in PDMS film was successfully fabricated using a femtosecond laser.

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지방간방(脂肪肝方)이 Ethanol로 유도(誘導)된 지방간(脂肪肝) 및 간재생능(肝再生能)에 미치는 영향(影響) (Influence of Gibangganbang on Ethanol-Induced Fatty Change and Regeneration Ability of Liver)

  • 심정섭;한상일;김강산
    • 대한한방내과학회지
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    • 제19권1호
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    • pp.3-21
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    • 1998
  • This study was to investigate the effects of Gibangganbang on the liver injury induced dimethylnitrosamine, CCl4, ethanol and partial hepatectomy. Hydroxyproline, hepatic fibrosis, hepatic inflammatory cell infiltration, fatty value, lipidoperoxide levels, glutathione levels, mitotic index, contents of protein in the serum and liver tissues were measured and observed. The results obtained were as follows. 1. The increasing level of hydroxyproline volume induced by dimethylnitrosamine in mice was decreased by the oral administration of Gibangganbang. 2. The degree of hitological fibrosis and hepatic inflammatory cell infiltration induced by $CCl_4$ was decreased by the oral administration of Gibangganbang. 3. The degree of fatty value and the increasing level of lipidoperoxide in liver tissues was decreased by the oral administration of Gibangganbang. 4. The level of glutathione in liver tissues was increasing by the oral administration of Gibangganbang. 5. The increasing level of microsomal lipidoperoxide in vitro assay was decreasing by the oral administration of Gibangganbang. 6. The increasing level of the mitotic index, weight of liver, contents of protein, RNA and DNA synthesis of the liver tissues after partial hepatectomy was activated by the oral administration of Gibangganbang. These results suggest that Gibangganbang not only inhibits liver cirrhotic change and ethanol-induced fatty change but also activates antioxidant enzymes and regeneration ability ocf liver.

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단파장 자외선(254 nm)에 노출된 고밀도 폴리에틸렌 수지의 카르보닐 지수(CI)와 기계적 물성 변화의 관계에 관한 연구 (A Study on the Relationship of Change of Mechanical Properties and Carbonyl Index Induced through Short-wavelength Ultraviolet Radiation (254 nm) for High Density Polyethylene)

  • 김창환;신진용
    • 공업화학
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    • 제24권2호
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    • pp.138-143
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    • 2013
  • 화학적 열화를 빠르게 유도할 수 있는 단파장의 자외선(254 nm)을 고밀도 폴리에틸렌의 표면에 조사하여, 생성된 carbonyl band의 변화로부터 기계적 물성 변화를 예측할 수 있는 지에 대한 가능성을 연구하였다. 오랜 시간이 요구되는 자연 태양광에 의한 옥외폭로시험이나, 제논-아크 광원에 의한 광 열화 대신에 광양자 에너지가 높은 UVC 램프를 사용함으로써, 유도되는 광열화의 화학적 특성이 동일한 기계적 물성 변화를 유발하는지를 확인하는 것에 본 연구의 의미가 있다. 인장시험과 크리프-파괴시험으로 진행된 고밀도 폴리에틸렌의 기계적 강도는 CI 변화에 유사한 양상을 보였으며, 특히 항복강도와 신장률은 자외선 노출시간과 밀접한 관계가 있음을 보여주었다. 따라서 빠른 표면 열화를 유발하는 UVC 램프를 활용한 카르보닐 지수와 기계적 물성 변화의 관계를 통하여 장시간이 요구되는 옥외에서의 기계적 물성변화를 보다 빠르게 파악할 수 있는 방법을 제시하였다.

Dextran Sulfate Sodium 유도 흰쥐 궤양성 대장염에 대한 산초 추출물의 효과 (The Effects of Zanthoxylum schinifolium Extract in a Dextran Sulfate Sodium-induced Rat Colitis Model)

  • 이경호;김병수;이기형
    • 생약학회지
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    • 제43권1호
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    • pp.22-26
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    • 2012
  • The aim of this study was to evaluate the anti-inlfammatory effect of the extract of Zanthoxylum schinifolium on ulcerative colitis induced by 3% dextran sulfate sodium in the rat. The experiment animals were divided into six groups: control (normal), DDS-induced colitis, 1 mg/kg, 15 mg/kg and 150 mg/kg of the extract of Z. schinifolium and 150 mg/kg of 5-aminosalicylic acid (5-ASA) as comparative drug. Anti-ulcerative colitis effect was evaluated pathologically by disease activity index (DAI), the change of weight and myeloperoxidase (MPO) in colon mucosa. Treatment with 15 mg/kg and 150 mg/kg of the extract of Z. schinifolium significantly improved the gain of body weight and DAI as clinical symptoms, and reduced MPO and $PGE_2$ level as biochemical index. Especially, 150 mg/kg of the extract of Z. schinifolium showed markedly more improvement than the same dose of 5-ASA in all kind of index such as MPO, $PGE_2$ and DAI. These results suggest that Z. schinifolium mediated anti-inflammatory action on colorectal sites may be a useful therapeutic approach to ulcerative colitis.

DWDM용 FBG 필터의 스펙트럼 해석에 관한 연구 (Spectral Analysis of the Fiber Brags Grating Filter for the Dense Wavelength Division Multiplexing)

  • 정종래;장진현;손용환;이창원;정진호
    • 전기전자학회논문지
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    • 제3권1호
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    • pp.133-140
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    • 1999
  • 기존의 광통신 시스템을 DWDM에 사용할 경우, 인접 채널사이의 간격이 좁아 심한 간섭이 발생한다. FBG 필터를 사용하여 DWDM에서의 이러한 인접 채널간 간섭은 줄일 수 있다. 따라서, 본 논문에서는 균일한 경우, 가우시안 apodized 경우, 상승-코사인 apodized 경우의 세가지 굴절을 변화에 대한 반사 스팩트럼을 구하였다. 본 논문에서 얻어진 결과로 부터, 균일한 FBG는 적합하지 않고, 최대 굴절을 변화량 ${\sigma}$ 가 작을수록, 상승-코사인 apodized FBG 인 경우 변수 C 가 클수록, 가우시안 apodized FBG 인 경우 변수 G가클수록 DWDM용 협대역 필터에 적합함을 알 수 있었다. 또한, 상승-코사인 apodized FBG는 더 좁은 반사 스펙트럼 대역과 더 낮은 사이드로브를 갖기 때문에 가우시안 apodized FBG보다 더 우수한 특성을 갖음을 알 수 있었다.

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