• Title/Summary/Keyword: OI

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SEARCH FOR AN OI EMISSION AT $1304{\AA}$ IN JOVIAN AUROAL SPECTRA

  • Kim, Sang-J.;Kim, Yong-H.
    • Publications of The Korean Astronomical Society
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    • v.10 no.1
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    • pp.127-134
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    • 1995
  • Recent discovery of an Io-related feature in Jupiter's auroral regions prompted us to search for an or multiplet at $1304{\AA}$ in IUE aurora spectra. In three independent IUE spectra taken on January 18, 1981, we found an emission structure at $1304{\AA}$, with a signal-to-noise of about three. If the structure is due to the OI emission, then it is a direct evidence of oxygen ion precipitation, which may originate from Io and Io torus. The emission rates of the $H_2$ band systems and the or multiplet are about 50 kR and 150 R, respectively. We have constructed high resolution model spectra with the estimated emission rates of $H_2$, OI and SI for the Goddard High Resolution Spectrograph (GHRS) onboard the Hubble Space Telescope. The model spectra clearly show the or and SI mulitplets separated from crowded $H_2$ Lyman and Werner band lines, and therefore it is promising to detect the OI and SI multiplets with the GHRS. Given the possibility that the lo-related feature may be caused by ion precipitations from the Io flux tube, it is likely that the OI emission may be detected in the footprint area of the IO flux tube.

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A Survey on Singapore University Students' Perceptions of Korean Commercial Kimchi (상업적 김치에 대한 싱가포르 대학생의 인식 조사)

  • Han, Jae-Sook;Han, Gyeong-Phil;Lee, Jin-Shik;Kim, Young-Jin
    • Journal of the East Asian Society of Dietary Life
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    • v.17 no.4
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    • pp.490-498
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    • 2007
  • The purpose of this study was to investigate the perception of Korean kimchi in Singapore. A questionnaire was given to male 236(43.0%) and female 313(57.0%) college students residing in Singapore. The results are as follows: 86.9% of the participants answered that kimchi is Korean in origin, and 48.7% had eaten kimchi. Also 75.2% of the males and 65.2% of the females had purchased commercial kimchi at restaurants(p<0.05). Regarding the primary reason they purchased commercial kimchi, 62.1% responded 'its taste'(male 58.1%, female 65.0%), also 47.6% stated the package size was 50g(male 44.8%, female 49.7%). Among the kimchi they had experienced, 86.7% had eaten Baechu kimchi, 31.0% Mu kimchi and 30.9% Oi kimchi(males : 82.2% Baechu kimchi, 30.9% Oi kimchi, and 27.4% Mu kimchi, females: 90.0% Baechu kimchi, 33.6% Mu kimchi, and 26.2% Oi kimchi respectively). For their kimchi preference, 67.0% preferred Baechu kimchi, 9.4% Oi kimchi, and 7.1% Mu kimchi(males: 63.4% Baechu kimchi, 12.9% Oi kimchi and 5.4% Mu kimchi, females: 69.5% Baechu kimchi, 8.4% Oi kimchi and 6.9% Mu kimchi, respectively). After having eaten kimchi, 19.3% answer it tasted good, and the primary reason for liking kimchi, 'spicy and hot taste'(51.3%), The main reasons for not liking kimchi were the odor(garlic, ginger, anchovy juice, etc) and too spicy, respectively. Regarding improvements for its expanded consumption 32.0% answered 'not to improve', 18.0% answered 'don't make it too hot', 17.6% answered 'don't make it too salty', and 9.4% answered 'don't make it over-ripe'. For the overall perception of kimchi, the answer with the highest mean(3.95) was 'kimchi is a good side dish with cooked rice', which was significantly different than 'kimchi is delicious'(M=3.14, p<0.05).

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Effect of Output-conductance on Current-gain Cut-off frequency in In0.8Ga0.2As High-Electron-mobility Transistors (In0.8Ga0.2As HEMT 소자에서 Output-conductance가 차단 주파수에 미치는 영향에 대한 연구)

  • Rho, Tae-Beom;Kim, Dae-Hyun
    • Journal of Sensor Science and Technology
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    • v.29 no.5
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    • pp.324-327
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    • 2020
  • The impact of output conductance (go) on the short-circuit current-gain cut-off frequency (fT) in In0.8Ga0.2As high-electron-mobility transistors (HEMTs) on an InP substrate was investigated. An attempted was made to extract the values of fT in a simplified small-signal model (SSM) of the HEMTs, derive an analytical formula for fT in terms of the extrinsic model parameters of the simplified SSM, which are related to the intrinsic model parameters of a general SSM, and verify its validity for devices with Lg from 260 to 25 nm. In long-channel devices, the effect of the intrinsic output conductance (goi) on fT was negligible. This was because, from the simplified SSM perspective, three model parameters, such as gm_ext, Cgs_ext and Cgd_ext, were weakly dependent on goi. However, in short-channel devices, goi was found to play a significant role in degrading fT as Lg was scaled down. The increase in goi in short-channel devices caused a considerable reduction in gm_ext and an overall increase in the total extrinsic gate capacitance, yielding a decrease in fT with goi. Finally, the results were used to infer how fT is influenced by goi in HEMTs, emphasizing that improving electrostatic integrity is also critical importance to benefit fully from scaling down Lg.

Osteogenesis of Human Adipose Tissue Derived Mesenchymal Stem Cells (ATMSCs) Seeded in Bioceramic-Poly D,L-Lactic-co-Glycolic Acid (PLGA) Scaffold (Bioceramic-Poly D,L-Lactic-co-Glycolic Acid(PLGA) Scaffold에 접종한 인간지방조직-유래 중간엽 줄기세포의 골 형성)

  • Kang, Yu-Mi;Hong, Soon-Gab;Do, Byung-Rok;Kim, Hae-Kwon;Lee, Joon-Yeong
    • Development and Reproduction
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    • v.15 no.2
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    • pp.87-98
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    • 2011
  • The present experiment was performed to evaluate the osteogenic differentiation of human adipose tissue derived mesenchymal stem cells (ATMSCs) seeded in bioceramic-poly D,L-latic-co-glycolic acid (PLGA) scaffold. Osteogenic differentiation of ATMSCs were induced using the osteogenic induction (OI) medium. ATMSCs were cultured with OI medium during 28 days in well plate. The proliferation of ATMSCs in OI medium group was significantly increased for 14 days of plate culture but slowed after 21 days. On the other hand, proliferation in the control group showed constant increase for 28 days of culturing. The alkaline phosphatase (ALP) activity of ATMSCs in OI medium group increased during the 21 days of culture but decreased on 28 days. However, in control group ALP activity of ATMSCs was continuously decreased as time goes. Nodule was observed at 21 days of culture in OI medium group and confirmed accumulation of calcium in cell by alizarin red staining. ATMSCs were seeded in PLGA scaffold or in Bioceramic-PLGA scaffold, and cultured with OI medium. ALP activity of ATMSCs by osteoblast differentiation in each scaffold increased on 21 days of culture and decreased rapidly on 28 days. ALP activity of ATMSCs was increased highly in Bioceramic-PLGA scaffold compared to PLGA scaffold on 21 days of culturing. SEM-EDS analysis demonstrated that calcium and phosphate content and Ca/P ratio in Bioceramic-PLGA scaffold increased higher than in PLGA scaffold. Biodegradability of scaffold at 56 days after implantation showed that Bioceramic-PLGA scaffold was more biodegradable than PLGA scaffold. The results demonstrated that the differentiation of ATMSCs to osteoblast were more effective in scaffold culture than well plate culture. Bioceramic increased cell adhesion rate on scaffold and ALP activity by osteoblast differentiation. Also, bioceramic was considered to increase the calcium and phosphate in scaffold when ATMSCs was mineralized by osteogenic differentiation. Bioceramic-PLGA scaffold enhanced the osteogenesis of seeded ATMSCs compared to PLGA scaffold.

Experimental Study of Estimating the Optimized Parameters in OI (서남해안 관측자료를 활용한 OI 자료동화의 최적 매개변수 산정 연구)

  • Gu, Bon-Ho;Woo, Seung-Buhm;Kim, Sangil
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.6
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    • pp.458-467
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    • 2019
  • The purpose of this study is the suggestion of optimized parameters in OI (Optimal Interpolation) by experimental study. The observation of applying optimal interpolation is ADCP (Acoustic Doppler Current Profiler) data at the southwestern sea of Korea. FVCOM (Finite Volume Coastal Ocean Model) is used for the barotropic model. OI is to the estimation of the gain matrix by a minimum value between the background error covariance and the observation error covariance using the least square method. The scaling factor and correlation radius are very important parameters for OI. It is used to calculate the weight between observation data and model data in the model domain. The optimized parameters from the experiments were found by the Taylor diagram. Constantly each observation point requires optimizing each parameter for the best assimilation. Also, a high accuracy of numerical model means background error covariance is low and then it can decrease all of the parameters in OI. In conclusion, it is expected to have prepared the foundation for research for the selection of ocean observation points and the construction of ocean prediction systems in the future.

mPW1PW91 Calculated Relative Stabilities and Structures for the Conformers of 1,3-dimethoxy-p-tert-butylthiacalix[4]crown-5-ether (1,3-디메톡시-티아캘릭스[4]크라운-5-에테르의 이형체들의 상대적인 안정성과 구조들에 대한 mPW1PW91 계산 연구)

  • Kim, Kwang-ho;Choe, Jong-In
    • Journal of the Korean Chemical Society
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    • v.53 no.5
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    • pp.521-529
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    • 2009
  • Molecular structures of the various conformers for the 1,3-dimethoxy-p-tert-butylthiacalix[4] crown-5-ether (3) were optimized by using DFT B3LYP/6 - 31 + G(d,p) and mPW1PW91/6 - 31 + G(d,p) (hybrid HF-DF) calculation methods. We have analyzed the energy differences and structures of eight in/out orientations (cone_oo, cone_oi, pc_oo, pc_io, pc_oi, pc_ii, 13a_oo, 13a_io) of two methoxy groups in three major conformations (cone, partial-cone and 1,3-alternate). The 13a_oo (out-out orientation of the 1,3-alternate conformer) is calculated to be the most stable among eight different conformations of 3, and in accord with the experimental result. The ordering of relative stability resulted from the mPW1PW91/6 - 31 + G(d,p) calculation method is following: 13a_oo > 13a_io$\sim$pc_io$\sim$cone_oo > cone_oi$\sim$pc_oo$\sim$pc_oi > pc_ii.

A Methodology for 3-D Optimally-Interpolated Satellite Sea Surface Temperature Field and Limitation (인공위성 해수면온도 3-D 최적 내삽 합성장 생산 방법과 한계점)

  • Park, Kyung-Ae;Kim, Young-Ho
    • Journal of the Korean earth science society
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    • v.30 no.2
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    • pp.223-233
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    • 2009
  • Three-dimensional (3-D) optimally-interpolated sea surface temperature (SST) field was produced by using AQUA/AMSR-E satellite data, and its limitations were described by comparing the temporal average of sea surface temperatures. The 3-D OI (Optimum Interpolation) SST showed a small error of less than $0.05^{\circ}C$ in the central North Pacific, but yielded large errors of greater than $0.4^{\circ}C$ at the coastal area where the satellite microwave data were not available. OI SST composite around pixels with no observation due to heavy rainfall or cloudy pixels had estimation errors of $0.1-0.15^{\circ}C$. Comparison with temporal means showed a tendency that overall OI SSTs were underestimated around heavy cloudy pixels and smoothed out by reducing the magnitude of SST fronts. In the low-latitude areas near the equator, OI SST field produced discontinuity, originated from the window size for the OI procedure. This was mainly caused by differences in the spatial scale of oceanic features. Infernal Rossby deformation radius, as a measure of spatial stale, showed dominant latitudinal variations with O(1) difference in the North Pacific. This study suggests that OI SST methodology should consider latitudinally-varying size of window and the characteristics of spatial scales of oceanic phenomena with substantial dependency on latitude and vertical structure of density.

Plasma L-Arginine Concentration, Oxygenation Index and Pulmonary Artery Pressure in Premature Infants with Respiratory Distress Syndrome (호흡곤란 증후군 미숙아에서 혈중 L-arginine 농도와 Oxygenation Index 및 폐동맥압과의 관계)

  • Jeong, Kyong Ah;Lee, Soon Ju;Sung, In Kyung;Chun, Chung Sik
    • Clinical and Experimental Pediatrics
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    • v.46 no.12
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    • pp.1207-1211
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    • 2003
  • Purpose : This study was performed to observe the relationship of plasma L-arginine level and the severity of disease and pulmonary artery pressure in respiratory distress syndrome of premature infants. Methods : Peripheral blood samples were obtained at 1st, 3rd and 7th day from 21 premature infants with respiratory distress syndrome to analyze the L-arginine concentration. Oxygenation index (OI), an indicator of the severity of the disease, was calculated at the same time of the blood sampling. And pulmonary artery pressure was measured by Doppler echocardiography at each period. Plasma L-arginine level, OI and right ventricular systolic time interval(RVSTI) were analyzed. Results : Plasma L-arginine concentration of the 1st day was lower than 3rd and 7th day. OI and RVSTI were significantly correlated with each other(r=0.772, P<0.01). Plasma L- arginine level was correlated with oxygenation index(r=-0.346, P<0.01) and RVSTI(r=-0.416, P<0.01). Conclusion : Plasma L-arginine level was lowest in the 1st day during the study period. Plasma L-arginine concentration correlated significantly with the severity of respiratory distress syndrome and pulmonary artery pressure in premature infants.

Dietary Behaviors, Health-related Lifestyle and Blood Lipid Profile of Obese Children in Incheon (인천시 비만초등학생의 식행동, 건강관련 생활습관 및 혈중 지질농도)

  • 이미영;김순기;장경자
    • Korean Journal of Community Nutrition
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    • v.7 no.6
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    • pp.803-813
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    • 2002
  • The purpose of this study was to investigate the anthropometric and blood biochemical characteristics, the dietary behaviors and health-related lifestyles of obese children in Incheon. A cross-sectional survey was conducted using anthropometric measurements, biochemical assessments and questionnaire analysis. The subjects included 7,055 obese children residing in the Incheon area (from 106 elementary schools). The degree of obesity was classified using the Obesity Index (OI) as light 20% < OI < 30% ; Medium 30% < OI < 50% ; Severe 50% > OI. The statistical analysis was conducted using SPSS 10.0 program. Most subjects fell within the medium range of obesity. Most subjects had dietary problems such as overeating, unbalanced meals and skipping breakfast. The ratio of boy subjects eating green and yellow vegetables was lowe. when compared to that of the girl subjects. The boy subjects exercised more frequently and longer than the girls. As the Obesity Index increased, hypercholesterolemia significantly increased. The blood cholesterol levels of the subjects were positively correlated with body fat, waist/hip ratio and BMI; HDL cholesterol levels of the subjects were negatively correlated with the anthropometric data and the LDL cholesterol levels of the subjects were positively correlated with body fat. The blood triglycerides levels of the subjects were positively correlated with body weight, body fat, waist/hip ratio and BMI. Therefore, proper nutritional education and intervention are required for an improvement of obese children's dietary behavior, heath-related factors and blood lipid profiles.

Comparison of Data Assimilation Methods in a Regional Ocean Circulation Model for the Yellow and East China Seas (자료동화 기법에 따른 황·동중국해 지역 해양순환모델 결과 비교)

  • Lee, Joon-Ho;Moon, Jae-Hong;Choi, Youngjin
    • Ocean and Polar Research
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    • v.42 no.3
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    • pp.179-194
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    • 2020
  • The present study aims to evaluate the effects of satellite-based SST (OSTIA) assimilation on a regional ocean circulation model for the Yellow and East China Seas (YECS), using three different assimilation methods: the Ensemble Optimal Interpolation (EnOI), Ensemble Kalman Filter (EnKF), and 4-Dimensional Variational (4DVAR) techniques, which are widely used in the ocean modeling communities. The model experiments show that an improved initial condition by assimilating the SST affects the seasonal water temperature and water mass distributions of the YECS. In particular, the SST data assimilation influences the temperature structures horizontally and vertically in winter, thereby improving the behavior of the YS warm current water. This is due to the fact that during wintertime the water column is well mixed, which is directly updated by the SST assimilation. The model comparisons indicate that the SST assimilation can improve the model performance in resolving the subsurface structures in wintertime, but has a relatively small impact in summertime due to the strong stratification. The differences among the different assimilation experiments are obvious when the SST was sharply changed due to a typhoon passage. Overall, the EnKF and 4DVAR show better agreement with the observations than the EnOI. The relatively low performance of EnOI under storm conditions may be related with a limitation of EnOI method whereby an analysis is obtained from a number of climatological fields, and thus the typhoon-induced SST changes in short-time scales may not be adequately reflected in the data assimilation.