• 제목/요약/키워드: analysis-dark current

검색결과 66건 처리시간 0.022초

탕약의 실온과 냉장보관 및 기간별 안정성에 대한 실험적 연구 (Stability Study for Herbal Drug According to Storage Conditions and Periods)

  • 손진영;신장우;손창규
    • 대한한의학회지
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    • 제30권2호
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    • pp.127-132
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    • 2009
  • Objectives: This study aimed to investigate the stability of a decoction using three herbal plants and their major components according to the storage conditions and periods. Materials and Methods: A three-herb mixture (1:1:1) of Glycyrrhiza uralensis Fischer, Artemisia capillaris Thunberg, and Poncirus trifoliata Rafinesqui was decocted and kept at room temperature ($25{\pm}2^{\circ}C$) or cold temperature ($4^{\circ}C$) for 0, 2, 4 or 8 weeks in liquid form in a plastic pack under dark conditions. At time points given, they were lyophilized. 200 mg of powdered samples were dissolved in 1 mL of 90% methanol and then applied to a high performance thin layer chromatography (HPTLC) with glycyrrhizin, 6,7-dimethoxycoumarin or poncirin for quantitative or qualitative analysis. Results: There were no gross changes in HPTLC-based compositional band-patterns of the three herbal mixture according to the storage conditions and period. The major components of each herb, glycyrrhizin, 6,7-dimethoxycoumarin and poncirin, showed slight time-dependent reduction in their contents both at room and cold temperature for 8 weeks. Conclusion: We could conclude that the current herbal decoction is generally safe for the stability at both RT or CT for at least 8 weeks. Nevertheless, we proposed that further advanced studies are required for more multiple herbal mixtures and longer storage periods.

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연령 변화에 따른 치조골의 디지탈 방사선학적 특성비교 (Comparison of digitized radiographic alveolar features with age)

  • 이건일
    • 치과방사선
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    • 제27권1호
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    • pp.17-24
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    • 1997
  • The purpose of the present study was to use digital profile image features and digital image analysis of fixed-dimension bone regions, extracted from standardized periapical radiographs of the maxilla, to determine whether differences exist in alveolar bone of younger women(mean age: 59.23±7.34 years) and just menopaused women(mean age: 59.23±7.34). Periapical films were used from two groups of 20 randomly selected women. None of the subjects had a remarkable medical history. To simplify protocol, we chose one interproximal bone area between the maxillary right canine and lateral incisor for study. Ech film was digitized into a 1312 x 1024 pixel x 8 bit depth matrix by means of a Nikon 35 mm film scanner(LS-35lOAF, Japan) with fixed gain and internal dark current correction to maintain constant illumination. The scanner was interfaced to a Macintosh LC III computer(Apple Computer, Charlotte, N.C.). Area and profile orientation were selected with a NIMH Image 1.37(NIH Research Services Branch, Bethesda, Md.). Histogram features were extracted from each profile and area. The results of this study indicate that mean pixel intensities didn't differ significantly between two groups and there was a high correlarion-coefficient between digitized radiographic profile features and area features.

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RNA 형광 검출을 위한 Finger형 PIN 광다이오드의 제작 및 평가 (Development and Characterization of Finger-type PIN Photodiode for Fluorescence Detection of RNA)

  • 김주환;오명환;주병권
    • 센서학회지
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    • 제13권2호
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    • pp.85-89
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    • 2004
  • This paper represents the development of high sensitivity photo-sensor for the fluorescence detection in the integrated biological analysis system. The finger-type PIN photodiodes were fabricated as the photo-sensor, and had a high sensitivity ($I_{light}/I_{dark}$ = 8720). The interference filter consisted of $TiO_{2}$ and $SiO_{2}$ was directly deposited on the photodiodes. Deposited filter with 95.5% reflection under 532 nm and 98% transmission over 580 nm exceedingly decreased the magnitude of background signal in the detection. The PDMS micro-fluidic channels are bonded on the photodiode by $O_{2}$ plasma treatment. The detection current was proportional to two primary parameters (light intensity, concentration), and the on-chip detection system could detect fluorescence signals down to 100 nM concentration (LOD = Limit of detection of rhodamine).

ERROR PROPAGATION ANALYSIS FOR IN-ORBIT GOCI RADIOMETRIC CALIBRATION

  • Kang, Gm-Sil;Youn, Heong-Sik
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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    • pp.92-95
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    • 2008
  • The Geostationary Ocean Color Imager (GOCI) is under development to provide a monitoring of ocean-color around the Korean Peninsula from geostationary platforms. It is planned to be loaded on Communication, Ocean, and Meteorological Satellite (COMS) of Korea. The GOCI has been designed to provide multi-spectral data to detect, monitor, quantify, and predict short term changes of coastal ocean environment for marine science research and application purpose. The target area of GOCI observation covers sea area around the Korean Peninsula. Based on the nonlinear radiometric model, the GOCI calibration method has been derived. The radiometric model of GOCI has been validated through radiometric ground test. From this ground test result, GOCI radiometric model has been changed from second order to third order. In this paper, the radiometric test performed to evaluate the radiometric nonlinearity is described and the GOCI radiometric error propagation is analyzed. The GOCI radiometric calibration is based on onboard calibration devices; solar diffuser, DAMD (Diffuser Aging Monitoring Device). The radiometric model error due to the dark current nonlinearity is considered as a systematic error. Also the offset correction error due to gain/offset instability is considered. The radiometric accuracy depends mainly on the ground characterization accuracies of solar diffuser and DAMD.

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Dark Sides of Engaging in Fan Community of Human Brand

  • Han, Jeongsoo;Kim, Chung K.;Kim, Miyea;Jun, Mina;Kim, Joshua Y.
    • Asia Marketing Journal
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    • 제16권1호
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    • pp.133-148
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    • 2014
  • People enthusiastic about human brands eagerly engage in fan communities to share their common interests with others. Although sharing one's enthusiasm towards the same celebrities can give thempositive senses of we-ness (in-group identity, togetherness, camaraderie) and belongingness, negative sides also exist such as schadenfreude and trash talk. Even though the studies addressing the negative sides of fan community are gaining significance, no prior studies formally examined the negative consequences of engaging in a fan community and their effect on one's well-being. Therefore, this current study aims to investigate how engaging in fan community negatively affects members' psychological well-being through schadenfreude and trash talk. Structural equation modeling analysis revealed that engaging highly in a fan community leads members to feel malicious pleasure at rivals' misfortunes and share negative opinions of rival human brands and fan communities. These negative consequences of fan community engagement ultimately lead to a lower level of psychological wellbeing, especially in the area of personal growth whereas fan community engagement has a direct positive effect on personal growth. By showing the negative influences of engaging in fan communities on members' well-being through schadenfreude and trash talk, the results of this study are expected to add depth to the existing literature.

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박막트랜지스터에 의해 구동되는 이미지센서 (The Image Sensor Operating by Thin Film Transistor)

  • 허창우
    • 한국정보통신학회논문지
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    • 제10권1호
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    • pp.111-116
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    • 2006
  • 본 연구에서는 비정질 실리콘 박막 트랜지스터를 스위칭소자로 포토센서를 구동 하는 방식의 이미지 센서를 구현하고자 한다. 먼저 PECVD(Plasma Enhanced Chemical Vapor Deposition) 진공 증착장비로 최적의 비정질실리콘 박막을 형성하고, 이 박막을 이용하여 스위칭소자인 박막트랜지스터와 광전변환소자인 광다이오드를 제조한다. 또한 이들을 결합하여 이미지 센서를 형성하고 그 특성 및 동작을 분석하고 최적의 동작특성을 이끌 수 있는 밀착이미지 센서를 제조한다. 제작한 이미지 센서를 측정한 결과 광전변환소자인 photodiode는 암전류의 경우 $\~10^{-l2}A$정도였으며, 광전류 $\~10^{-9}A$정도로서 Iphoto/Idark ${\ge}10^3$ 이상을 이루어 좋은 광전변환 특성을 갖고 있었다. 또한 a-Si:H TFT의 경우 Ioff ${\le}10^{-l2}A$, Ion ${\le}10^{-6}A$ 으로서 Ion/Ioff ${le}10^6$ 이상을 나타냈으며 Vth는 $2\~4$ volts였고, Id는 수 ${\mu}A$ 정도로 photodiode를 스위치하기에 충분한 전류-전압특성을 나타내고 있다. 이미지 센서 전체 동작 특성을 측정하기 위하여 photodiode의 ITO쪽에 -5volts의 역 bias를 가한 상태에서 TFT의 gate에 $70\;{\mu}sec$의 pulse를 가하여 photodiode에서 생성된 광전류 와 암전류를 측정하였다. 이렇게 하여 측정된 전압은 암상태에서 수십 mvolts이고, 광상태에서는 수백 mvolts로 나타나 우수한 이미지센서 특성을 갖고 있음을 확인하였다.

II-VI족 화합물 반도체의 결정성장 및 센서 개발에 관한 연구 (Crystal Growth Sensor Development of II-VI Compound Semiconductor : CdS)

  • D.I. Yang;Y.J. Shin;S.Y. Lim;Y.D. Choi
    • 한국진공학회지
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    • 제1권1호
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    • pp.126-133
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    • 1992
  • E-Beam 기법을 이용하여 증착시킨 Ag doped CdS 박막은 육방정계이고 공기, Ar 분위기에서 $^550{\circ}C$로 열처리한 결과 grain size가 1$mu extrm{m}$ 정도로 성장되었고, Van Der Pauw 방법으로 구한 Hall data로부터 CdS crystal은 n형 반도체이고 상온에서의 carrier 농 도는 2.7 $\times$ 1011cm-3이고 Hall mobility는 5.8 $\times$ 102cm2V-1sec-1정도임을 알 수 있었다. CdS : Ag 박막의 PL spectra는 Gaussian curve를 보여주었고, spectra peak는 파장이 520nm 근처에 위치하고 있으며, CdS : Ag 박막에서의 광전류(pc)와 암전류(dc)의 ratio(pc/dc)는 공기 중에서 열처리한 시료의 값이 크다는 것을 알 수 있었다.

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Compositional analysis by NIRS diode array instrumentation on forage harvesters

  • Andreashaeusler, Michael Rode;Christian, Paul
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1619-1619
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    • 2001
  • Ourwork aims to assess the content of dry matter, protein, cell wall parameters and water soluble carbohydrates in forages without having to handle samples, transport them to a laboratory, dry, grind and chemically analyze them. for this purpose, the concept of fresh forage analysis under field conditions by means of compact integrated NIRS InGaAs-diode array instruments on small plot harvesters is being evaluated for plant breeding trials. This work was performed with the world first commercial experimental forage plot harvester equipped with a NIRS module for the collection, compression, and scanning of forage samples (including automatic referencing and dark current measure ments). It was used for harvesting and analyzing a number of typical forage grass and forage legume plot trials. After NIRS measurements in the field each sample was again analyzed in the laboratory by means of a conventional grating spectrometer equipped with Si-and PbS-detectors. Conventional laboratory analysis of the samples was restricted to dry matter (DM) content by means of oven drying at 105. Routine chemometric procedures were then employed to assess the comparative accuracy and precision of the DM assessments in the spectral range between 950 and 1650nm by the NIRS diode array as well as by the conventional NIRS scanning instrument. The results of this study confirmed that the type of NIRS diode array instrument employed here functioned well even in rugged field operations. further refinements proved to be necessary for optimizing the automatic filling of the sample compartment to adjust for the wide variation in forage material under conditions of extremely low or high harvest yields. The error achieved in calibrating the apparatus for forages of typical DM content proved to be satisfactory (SECV < 1.0). Possibly as a consequence of higher sampling errors, its performance in atypical forages with elevated DM contents was less satisfactory. The error level obtained on the conventional grating NIR spectrometer was similar to that of the diode array instrument for both types of forage.

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Transcriptomic analysis of the liver in aged laying hens with different intensity of brown eggshell color

  • Han, Gi Ppeum;Kim, Jun-Mo;Kang, Hwan Ku;Kil, Dong Yong
    • Animal Bioscience
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    • 제34권5호
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    • pp.811-823
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    • 2021
  • Objective: Eggshell color is an important indicator of egg quality for consumers, especially for brown eggs. Various factors related to laying hens and their environment affect brown eggshell coloration. However, there have been no studies investigating hepatic functions of laying hens with variable intensity of brown eggshell color. Therefore, this study was aimed to identify potential factors affecting brown eggshell coloration in aged laying hens at the hepatic transcriptomic level. Methods: Five hundred 92-wk-old Hy-line Brown laying hens were screened to select laying hens with different intensity of brown eggshell color based on eggshell color fans. Based on eggshell color scores, hens with dark brown eggshells (DBE; eggshell color fan score = 14.8) and hens with light brown eggshells (LBE; eggshell color fan score = 9.7) were finally selected for the liver sampling. We performed RNA-seq analysis using the liver samples through the paired-end sequencing libraries. Differentially expressed genes (DEGs) profiling was carried out to identify their biological meaning by bioinformatics. Results: A total of 290 DEGs were identified with 196 being up-regulated and 94 being down-regulated in DBE groups as compared to LBE groups. The Kyoto encyclopedia of genes and genomes (KEGG) analysis revealed that these DEGs belong to several biological pathways including herpes simplex infection (toll-like receptor 3 [TLR3], cyclin-dependent kinase 1, etc.) and influenza A (TLR3, radical S-adenosyl methionine domain containing 2, myxovirus [influenza virus] resistance 1, etc.). Genes related to stress response (ceremide kinase like) and nutrient metabolism (phosphoenolpyruvate carboxy-kinase 1, methylmalonic aciduria [cobalamin deficiency] cblB type, glycine receptor alpha 2, solute carrier family 7 member 11, etc.) were also identified to be differentially expressed. Conclusion: The current results provide new insights regarding hepatic molecular functions related to different intensity of brown eggshell color in aged laying hens. These insights will contribute to future studies aiming to optimize brown eggshell coloration in aged laying hens.

Si 기판위에 열증착법으로 제조한 copper phthalocyanine(CuPc) 박막의 구조 및 광전특성 (Structural and photoelectrical properties of copper phthalocyanine(CuPc) thin film on Si substrate by thermal evaporation)

  • 이혜연;정중현;이종규
    • 센서학회지
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    • 제6권5호
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    • pp.407-413
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    • 1997
  • 기판온도 $300^{\circ}C$에서 열증착법에 의해 p형 <100> Si 기판위에 CuPc(Copper Phthalocyanine) 결정 박막을 증착하였다. X선 회절분석으로부터 CuPc 박막은 a-축 방향으로 성장하였음을 알 수 있었다. CuPc분자들이 기판면위에 수직인 CuPc/Si박막의 광전특성을 조사하기 위하여 수직방향의 전류-전압 (I-V) 특성을 기판 Si의 특성과 비교 관찰하였다. 저항성 접촉을 위해 기판인 p형 Si위에 전극으로 Au를 증착시켰다. Au/Si 접합에 빛을 조사한 결과 전류는 증가하지만 광기전력효과는 관찰되지 않았다. p형 반도체인 CuPc 박막과 기판 p-Si의 접합은 장벽을 형성하지 않기 때문에 빛을 조사하지 않았을 때의 I-V 특성은 저항성을 나타낸다. 빛을 조사하였을 때 CuPc/Si 접합의 증가된 광전류는 Si 웨이퍼보다 현저하게 큰 것을 알 수 있다. 따라서 CuPc 층이 600 nm 파장에서의 붉은 빛을 현저하게 흡수하여 광전류에 기여하는 다량의 광캐리어를 형성함을 알 수 있다. CuPc/Si 박막은 $J_{sc}$ (short-circuit photocurrent) $4.29\;mA/cm^{2}$$V_{oc}$ (open circuit photovoltage) 12 mV의 광기전력 특성을 보여준다.

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