• Title/Summary/Keyword: 광학적특성

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Effects of Optical Characteristics on the Growth of Benthic Microalga, Nitzschia sp. and Its Growth Kinetics of Phosphate for Bioremediation (생물적 환경정화를 위한 부착미세조류 Nitzschia sp.의 생장에 미치는 광학적 특성과 그에 따른 인산염 성장 동력학)

  • Oh, Seok-Jin;Kang, In-Seok;Yoon, Yang-Ho;Yang, Han-Soeb;Park, Jong-Sick
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.4
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    • pp.205-212
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    • 2009
  • To suggest possible to bioremediation by benthic microalgae Nitzschia sp. isolated from the Jinhae Bay, the studies investigated the effects o flight quality and quantity on the growth of Nitzschia sp. and its growth kinetics for phosphate investigated. The Nitzschia sp. was cultured under blue (450 nm), yellow (590 nm) and red wavelength (650 nm) using light emitting diode (LED) and mixed wavelengths using a fluorescent lamp. The maximum specific growth rate showed the Nitzschia sp. under blue wavelength, although photoinhibition was observed above $100\;{\mu}mol\;m^{-2}\;s^{-1}$. Mixed wavelengths were also observed by decreasing the maximum cell density from high irradiances (>$100\;{\mu}mol$ photons $m^{-2}\;s^{-1}$). The compensation photon flux density ($I_0$) calculated from the mixed wavelengths equated to a depth of 4-10 m in Jinhae Bay, and was lower in the summer season than the depth due to suspended matter (ca. 4 m). Thus, the suitable depth for maximum growth of Nitzschia sp. might be extremely limited. In the growth kinetics for phosphate, half-saturation constant ($K_s$) was similar among different wavelengths, although the maximum growth rate was varied among different wavelengths. Because the $K_s$ was high than that of the phytoplankton, Nitzschia sp. might have adapted to the high nutrient concentrations, and have effective nutrient storage in the cell quota. Thus, Nitzschia sp. may be a useful species for bioremediation of the benthic layer in polluted inner bays by means of irradiated specific wavelength as blue.

Detection of Helicobacter pylori by Pre-embedding Immunoelectron Microscopy - Comparison with Immunoblotting Method (Pre-embedding Immunoelectron Microscopy를 이용한 Helicobacter pylori의 발견 - Immunoblotting법과 비교 -)

  • Jung, Hae-Seoung;Kim, Eun-Jung;Kim, Eun-A;Park, Ji-Hoe;Jun, Jin-Su;Seo, Ji-Hyoun;Lim, Jae-Young;Choi, Myoung-Bum;Woo, Hyang-Ok;Youn, Hee-Shang;Ko, Gyung-Hyuck;Baik, Seung-Chul;Lee, Woo-Kon;Cho, Myung-Je;Rhee, Kwang-Ho
    • Clinical and Experimental Pediatrics
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    • v.45 no.7
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    • pp.862-874
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    • 2002
  • Purpose : We tried to evaluate whether the detection rate of Helicobacter pylori in gastric biopsy specimens could be improved by using pre-embedding immunoelectron microscopy. Methods : A total of 119 children who complained of upper gastrointestinal symptoms were endoscoped at the Gyeongsang National University Hospital from July, 1996 to July, 1999. Five biopsy specimens(three for urease test, one for hematoxylin-eosin(H & E) staining, and one for preembedding immunoelectron microscopy) were obtained from each antrum and body. Immunoblotting analysis were also performed. Results : Among the 119 patients, H. pylori were found in 116 patients(97.5%) by the immunoelectron microscopy. Among three patients who were found H. pylori negative in immunoelectron microscopy, two patients showed H. pylori in H & E stained slides and one patient was urease test positive(color change within six hours). Urease tests were positive in 107 patients(89.9 %). The positive rate of immunoblotting tests was 81.5%. However, only 13 patients(10.9%) showed H. pylori on the H & E stained antrum or body tissue. Conclusion : In this study, we found H. pylori histopathologically in most of the pediatric patients who complained of upper gastrointestinal symptoms. This study showed that pre-embedding immunoelectron microscopic examinations can be used as a gold standard in the diagnosis of childhood H. pylori infection. However, this method also has limited capacity to detect widely scattered H. pylori compared to the other histopathologic diagnostic methods.

Empirical Estimation and Diurnal Patterns of Surface PM2.5 Concentration in Seoul Using GOCI AOD (GOCI AOD를 이용한 서울 지역 지상 PM2.5 농도의 경험적 추정 및 일 변동성 분석)

  • Kim, Sang-Min;Yoon, Jongmin;Moon, Kyung-Jung;Kim, Deok-Rae;Koo, Ja-Ho;Choi, Myungje;Kim, Kwang Nyun;Lee, Yun Gon
    • Korean Journal of Remote Sensing
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    • v.34 no.3
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    • pp.451-463
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    • 2018
  • The empirical/statistical models to estimate the ground Particulate Matter ($PM_{2.5}$) concentration from Geostationary Ocean Color Imager (GOCI) Aerosol Optical Depth (AOD) product were developed and analyzed for the period of 2015 in Seoul, South Korea. In the model construction of AOD-$PM_{2.5}$, two vertical correction methods using the planetary boundary layer height and the vertical ratio of aerosol, and humidity correction method using the hygroscopic growth factor were applied to respective models. The vertical correction for AOD and humidity correction for $PM_{2.5}$ concentration played an important role in improving accuracy of overall estimation. The multiple linear regression (MLR) models with additional meteorological factors (wind speed, visibility, and air temperature) affecting AOD and $PM_{2.5}$ relationships were constructed for the whole year and each season. As a result, determination coefficients of MLR models were significantly increased, compared to those of empirical models. In this study, we analyzed the seasonal, monthly and diurnal characteristics of AOD-$PM_{2.5}$model. when the MLR model is seasonally constructed, underestimation tendency in high $PM_{2.5}$ cases for the whole year were improved. The monthly and diurnal patterns of observed $PM_{2.5}$ and estimated $PM_{2.5}$ were similar. The results of this study, which estimates surface $PM_{2.5}$ concentration using geostationary satellite AOD, are expected to be applicable to the future GK-2A and GK-2B.

Studies on the Solubility Phenomenon and Activities of Silk Cocoon Sericin through the Filature Water Conditions. (제사용수의 수질이 견층세리신의 용해에 미치는 거동구명에 관한 연구)

  • 김병호
    • Journal of Sericultural and Entomological Science
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    • v.16 no.2
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    • pp.77-98
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    • 1974
  • This study was carried out ill an attempt to investigate the properties and activities of sericin obtained from silk cocoon shells in silk reeling water through various instrumental analyses. In addition, the effects of the characteristics in sericin solubility on the reeling process and silk qualities were also studied on the basis of tile above conditions. The results obtained are as follows: I. The sericin properties and activities through various analytical instruments. 1. The water solubility of each amino acid such as serine, glycine. glutamic and aspartic acids against the pH modified water by using automatic amino acid analyzer, showed the lowest solubility at PH 5, but it increased according to drifting toward the alkalinity. 2. When the obtained sericin particles by water pH variation were observed with the electronic microscope, it was found for the sericin Particles to expand in the alkaline regions. 3. The IR spectrum results showed the differences among the pH modified sericin solutions at the range of 2,100cm-1 and 1.890cm-1 of wave number. 4. The existence of sericin with in silk fabrics made differences in the X-ray interference intencity, that is, the non-degummed fabrics had the interference peak at 2$\theta$=14$^{\circ}$, 17$^{\circ}$, 24$^{\circ}$, and the degummed ones had it at 2$\theta$=17$^{\circ}$, 18$^{\circ}$, 20$^{\circ}$, 23$^{\circ}$, 26$^{\circ}$. II. The results of sericin solubility for silk reeling process. 1. The sericin solubility and swelling had a tendency to increase up with high M-alkalinity and pH value of water. But in case of acidity. water hardness and concentration of ethylene glycol were high, the sericin solubility and swelling were decreased. 2. With the filature experiments, the best conditions of filature orator are summarized as fellows ; a. pH; 6.9${\pm}$0.2 d. acidity; below10ppm b. total hardness; 55:5ppm e. Fe ion; none c. M-alkalinity; 40${\pm}$10ppm

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Impact of Lambertian Cloud Top Pressure Error on Ozone Profile Retrieval Using OMI (램버시안 구름 모델의 운정기압 오차가 OMI 오존 프로파일 산출에 미치는 영향)

  • Nam, Hyeonshik;Kim, Jae Hawn;Shin, Daegeun;Baek, Kanghyun
    • Korean Journal of Remote Sensing
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    • v.35 no.3
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    • pp.347-358
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    • 2019
  • Lambertian cloud model (Lambertian Cloud Model) is the simplified cloud model which is used to effectively retrieve the vertical ozone distribution of the atmosphere where the clouds exist. By using the Lambertian cloud model, the optical characteristics of clouds required for radiative transfer simulation are parametrized by Optical Centroid Cloud Pressure (OCCP) and Effective Cloud Fraction (ECF), and the accuracy of each parameter greatly affects the radiation simulation accuracy. However, it is very difficult to generalize the vertical ozone error due to the OCCP error because it varies depending on the radiation environment and algorithm setting. In addition, it is also difficult to analyze the effect of OCCP error because it is mixed with other errors that occur in the vertical ozone calculation process. This study analyzed the ozone retrieval error due to OCCP error using two methods. First, we simulated the impact of OCCP error on ozone retrieval based on Optimal Estimation. Using LIDORT radiation model, the radiation error due to the OCCP error is calculated. In order to convert the radiation error to the ozone calculation error, the radiation error is assigned to the conversion equation of the optimal estimation method. The results show that when the OCCP error occurs by 100 hPa, the total ozone is overestimated by 2.7%. Second, a case analysis is carried out to find the ozone retrieval error due to OCCP error. For the case analysis, the ozone retrieval error is simulated assuming OCCP error and compared with the ozone error in the case of PROFOZ 2005-2006, an OMI ozone profile product. In order to define the ozone error in the case, we assumed an ideal assumption. Considering albedo, and the horizontal change of ozone for satisfying the assumption, the 49 cases are selected. As a result, 27 out of 49 cases(about 55%)showed a correlation of 0.5 or more. This result show that the error of OCCP has a significant influence on the accuracy of ozone profile calculation.

An Artificial Intelligence Approach to Waterbody Detection of the Agricultural Reservoirs in South Korea Using Sentinel-1 SAR Images (Sentinel-1 SAR 영상과 AI 기법을 이용한 국내 중소규모 농업저수지의 수표면적 산출)

  • Choi, Soyeon;Youn, Youjeong;Kang, Jonggu;Park, Ganghyun;Kim, Geunah;Lee, Seulchan;Choi, Minha;Jeong, Hagyu;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.38 no.5_3
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    • pp.925-938
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    • 2022
  • Agricultural reservoirs are an important water resource nationwide and vulnerable to abnormal climate effects such as drought caused by climate change. Therefore, it is required enhanced management for appropriate operation. Although water-level tracking is necessary through continuous monitoring, it is challenging to measure and observe on-site due to practical problems. This study presents an objective comparison between multiple AI models for water-body extraction using radar images that have the advantages of wide coverage, and frequent revisit time. The proposed methods in this study used Sentinel-1 Synthetic Aperture Radar (SAR) images, and unlike common methods of water extraction based on optical images, they are suitable for long-term monitoring because they are less affected by the weather conditions. We built four AI models such as Support Vector Machine (SVM), Random Forest (RF), Artificial Neural Network (ANN), and Automated Machine Learning (AutoML) using drone images, sentinel-1 SAR and DSM data. There are total of 22 reservoirs of less than 1 million tons for the study, including small and medium-sized reservoirs with an effective storage capacity of less than 300,000 tons. 45 images from 22 reservoirs were used for model training and verification, and the results show that the AutoML model was 0.01 to 0.03 better in the water Intersection over Union (IoU) than the other three models, with Accuracy=0.92 and mIoU=0.81 in a test. As the result, AutoML performed as well as the classical machine learning methods and it is expected that the applicability of the water-body extraction technique by AutoML to monitor reservoirs automatically.

Study on Confectionary Properties of Chou made with Flour of Rice and Rice-Wheat mixture (미분을 이용한 chou의 제과특성 연구)

  • 김명애;오승희
    • Korean journal of food and cookery science
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    • v.11 no.1
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    • pp.69-76
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    • 1995
  • This study was concentrated on the subject of chou formation and physicochemical characteristics on medium flour mixed with 0, 25, 50, 75, 100% of rice flour in order to clarify the possibility to substitute rice flour for wheat flour on chou preparation. The water holding capacity, swelling power, and maximum viscosity were higher in rice flour than those in medium flour but the initial pasting temperature was equal to 65$^{\circ}C$ in the two flour groups. The ratio of setback during cooling became 0.94 in the rice flour and 1.14 in the medium flour. So, the rice flour showed a slow tendency during gel formation as compared with the medium flour. The volumes of the rice choux were ranged from 80.0% to 89.0% according to the mixing ratio of medium flour as compared with that of the chou of wheat flour. But, the choux formation were increased as much as 108.8% out the paste added gelation of glutinous substance and 124.4% at the paste added Span20 of emulsifier compared to the non-addition treatment. The paste of rice flour added gelatin and Span20 showed better dispersion of components, especially, the small granules of lipid were fairly or plentifully dispersed in the paste added Span20 due to emulsifying activity. In sensory evaluation, the chou of l00% rice flour was inferior to that of medium flour on cavity-forming but the choux of wheat flour mixed with 25%, 50%, and 75% of rice flour were equal or superior to that of medium flour on all characteristics tested such as appearance, surface color, cavity-forming, chewiness, and taste. There were no significant differences on the cavity-forming expansion and taste between choux of rice flour and wheat flour Therefore, the results of this study made conclusion that rice flour would be substituted for wheat flour on the chou preparation.

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Characteristic Response of the OSMI Bands to Estimate Chlorophyll $\alpha$ (클로로필 $\alpha$ 추정시 OSMI 밴드의 광학 반응 특성)

  • 서영상;이나경;장이현;황재동;유신재;임효숙
    • Korean Journal of Remote Sensing
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    • v.18 no.4
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    • pp.187-199
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    • 2002
  • Correlation between chlorophyll a in the East China Sea and spectral bands (412, 443, 490, (510), 555, (676, 765)nm) of Ocean Scanning Multi-Spectral Imager (OSMI) including the profile multi-spectral radiometer (PRR-800) was studied. The values of remote sensing reflectance (Rrs) at the bands corresponding to the field chlorophyll $\alpha$ in the East China Sea were much higher than those in clear waters off California, USA. In case of the particle absorptions related to the chlorophyll a concentration at the spectral bands (440, 670nm) were much higher in the East China Sea than the ones in the clean waters off California. The normalized water leaving radiances (nLw) at 412, 443, 490, 555 nm of OSMI and the field chlorophyll a in the East China Sea were correlated each other. According to the results, the relationship between field chlorophyll $\alpha$ and nLw 410 nm in OSMI bands was the lowest, whereas that between field chlorophyll a and nLw 555 nm in the bands was the highest. Reciprocal action between the field chlorophyll a and the band ratio of the OSMI bands (nLw410/nLw555, nLw443/nLw555, nLw490/nLw555) was also studied. Relationship between the chlorophyll $\alpha$ and the band ratio (nLw490/nLw555) was highest in the OSMI bands. Relationship between the chlorophyll $\alpha$ and the ratio (nLw490/nLw555) was higher than one in the nLw410/nLw555. The difference in the estimated chlorophyll $\alpha$ (mg/m$^3$) between OSMI and SeaWiFS (Sea Viewing Wide Field-of-View Sensor) at the special observing stations in the northern eastern sea of Jeju Island in February 25, 2002 was about less than 0.3 mg/m$^3$ within 3 hours. It is suggested that OC2 (ocean color chlorophyll 2 algorithm) be used to get much better estimation of chlorophyll $\alpha$ from OSMI than the ones from the updated algorithms as OC4.

Influences of the Composition on Spectroscopic Characteristics of AlxGa1-xN Thin Films (AlxGa1-xN 박막의 조성이 분광학적 특성에 미치는 영향)

  • Kim, Dae Jung;Kim, Bong Jin;Kim, Duk Hyeon;Lee, Jong Won
    • New Physics: Sae Mulli
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    • v.68 no.12
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    • pp.1281-1287
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    • 2018
  • In this study, $Al_xGa_{1-x}N$ films were grown on (0001) sapphire substrates by using metal-organic chemical vapor deposition (MOCVD). The crystallinity of the grown films was examined with X-ray diffraction (XRD) patterns. The surfaces and the chemical properties of the $Al_xGa_{1-x}N$ films were investigated using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS), respectively. The optical properties of the $Al_xGa_{1-x}N$ film were studied in a wide photon energy range between 2.0 ~ 8.7 eV by using spectroscopic ellipsometry (SE) at room temperature. The data obtained by using SE were analyzed to find the critical points of the pseudodielectric function spectra, $<{\varepsilon}(E)>=<{\varepsilon}_1(E)>+i<{\varepsilon}_2(E)>$. In addition, the second derivative spectra, $d^2<{\varepsilon}(E)>/dE^2$, of the pseudodielectric function for the $Al_xGa_{1-x}N$ films were numerically calculated to determine the critical points (CPs), such as the $E_0$, $E_1$, and $E_2$ structure. For the four samples (x = 0.18, 0.21, 0.25, 0.29) between a composition of x = 0.18 and x = 0.29, changes in the critical points (blue-shifts) with increasing Al composition at 300 K for the $Al_xGa_{1-x}N$ film were observed via ellipsometric measurements for the first time.

Fog Detection over the Korean Peninsula Derived from Satellite Observations of Polar-orbit (MODIS) and Geostationary (GOES-9) (극궤도(MODIS) 및 정지궤도(GOES-9) 위성 관측을 이용한 한반도에서의 안개 탐지)

  • Yoo, Jung-Moon;Yun, Mi-Young;Jeong, Myeong-Jae;Ahn, Myoung-Hwan
    • Journal of the Korean earth science society
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    • v.27 no.4
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    • pp.450-463
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    • 2006
  • Seasonal threshold values for fog detection over the ten airport areas within the Korean Peninsula have been derived from the data of polar-orbit Aqua/Terra MODIS and geostationary GOES-9 during a two years. The values are obtained from reflectance at $0.65{\mu}m\;(R_{0.65})$ and the difference in brightness temperature between $3.7{\mu}m\;and\;11{\mu}m\;(T_{3.7-11})$. In order to examine the discrepancy between the threshold values of two kinds of satellites, the following four parameters have been analyzed under the condition of daytime/nighttime and fog/clear-sky, utilizing their simultaneous observations over the Seoul metropolitan area: brightness temperature at $3.7{\mu}m$, the temperature at $11{\mu}m,\;the\;T_{3.7-11}$ for day and night, and the $R_{0.65}$ for daytime. The parameters show significant correlations (r<0.5) in spatial distribution between the two kinds of satellites. The discrepancy between their infrared thresholds is mainly due to the disagreement in their spatial resolutions and spectral bands, particularly at $3.7{\mu}m$. Fog detection from GOES-9 over the nine airport areas except the Cheongju airport has revealed accuracy of 60% in the daytime and 70% in the nighttime, based on statistical verification. The accuracy decreases in foggy cases with twilight, precipitation, short persistence, or the higher cloud above fog. The sensitivity of radiance and reflectance with wavelength has been analyzed in numerical experiments with respect to various meteorological conditions to investigate optical characteristics of the three channels.