• Title/Summary/Keyword: K Band

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Estimation of Water Quality Index for Coastal Areas in Korea Using GOCI Satellite Data Based on Machine Learning Approaches (GOCI 위성영상과 기계학습을 이용한 한반도 연안 수질평가지수 추정)

  • Jang, Eunna;Im, Jungho;Ha, Sunghyun;Lee, Sanggyun;Park, Young-Gyu
    • Korean Journal of Remote Sensing
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    • v.32 no.3
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    • pp.221-234
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    • 2016
  • In Korea, most industrial parks and major cities are located in coastal areas, which results in serious environmental problems in both coastal land and ocean. In order to effectively manage such problems especially in coastal ocean, water quality should be monitored. As there are many factors that influence water quality, the Korean Government proposed an integrated Water Quality Index (WQI) based on in situmeasurements of ocean parameters(bottom dissolved oxygen, chlorophyll-a concentration, secchi disk depth, dissolved inorganic nitrogen, and dissolved inorganic phosphorus) by ocean division identified based on their ecological characteristics. Field-measured WQI, however, does not provide spatial continuity over vast areas. Satellite remote sensing can be an alternative for identifying WQI for surface water. In this study, two schemes were examined to estimate coastal WQI around Korea peninsula using in situ measurements data and Geostationary Ocean Color Imager (GOCI) satellite imagery from 2011 to 2013 based on machine learning approaches. Scheme 1 calculates WQI using estimated water quality-related factors using GOCI reflectance data, and scheme 2 estimates WQI using GOCI band reflectance data and basic products(chlorophyll-a, suspended sediment, colored dissolved organic matter). Three machine learning approaches including Random Forest (RF), Support Vector Regression (SVR), and a modified regression tree(Cubist) were used. Results show that estimation of secchi disk depth produced the highest accuracy among the ocean parameters, and RF performed best regardless of water quality-related factors. However, the accuracy of WQI from scheme 1 was lower than that from scheme 2 due to the estimation errors inherent from water quality-related factors and the uncertainty of bottom dissolved oxygen. In overall, scheme 2 appears more appropriate for estimating WQI for surface water in coastal areas and chlorophyll-a concentration was identified the most contributing factor to the estimation of WQI.

SVC Based Multi-channel Transmission of High Definition Multimedia and Its Improved Service Efficiency (SVC 적용에 의한 다매체 멀티미디어 지원 서비스 효율 향상 기법)

  • Kim, Dong-Hwan;Cho, Min-Kyu;Moon, Seong-Pil;Lee, Jae-Yeal;Jun, Jun-Gil;Chang, Tae-Gyu
    • Journal of IKEEE
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    • v.15 no.2
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    • pp.179-189
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    • 2011
  • This paper presents an SVC based multi-channel transmission technique. Transmission of high definition multimedia and its service efficiency can be significantly improved by the proposed method. In this method, the HD stream is divided into the two layer streams, i.e., a base layer stream and an enhancement layer stream. The divided streams are transmitted through a primary channel and an auxiliary channel, respectively. The proposed technique provides a noble mode switching technique which enables a seamless service of HD multimedia even under the conditions of abrupt and intermittent deterioration of the auxiliary channel. When the enhancement layer stream is disrupted by the channel monitoring in the mode switching algorithm, the algorithm works further to maintain the spatial and time resolution of the HD multimedia by upsampling and interpolating the base layer stream, consequently serving for the non disrupted play of the media. Moreover, the adoption of an adaptive switching algorithm significantly reduces the frequency of channel disruption avoiding the unnecessary switching for the short period variations of the channel. The feasibility of the proposed technique is verified through the simulation study with an example application to the simultaneous utilization of both Ku and Ka bands for HD multimedia broadcasting service. The rainfall modeling and the analysis of the satellite channel attenuation characteristics are performed to simulate the quality of service performance of the proposed HD broadcasting method. The simulation results obtained under a relatively poor channel (weather) situations show that the average lasting period of enhancement layer service is extended from 9.48[min] to 23.12[min] and the average switching frequency is reduced from 3.84[times/hour] to 1.68[times/hour]. It is verified in the satellite example that the proposed SVC based transmission technique best utilizes the Ka band channel for the service of HD broadcasting, although it is characterized by its inherent weather related poor reliability causing severe limitations in its independent application.

Development of relative radiometric calibration system for in-situ measurement spectroradiometers (현장관측용 분광 광도계의 상대 검교정 시스템 개발)

  • Oh, Eunsong;Ahn, Ki-Beom;Kang, Hyukmo;Cho, Seong-Ick;Park, Young-Je
    • Korean Journal of Remote Sensing
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    • v.30 no.4
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    • pp.455-464
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    • 2014
  • After launching the Geostationary Ocean Color Imager (GOCI) on June 2010, field campaigns were performed routinely around Korean peninsula to collect in-situ data for calibration and validation. Key measurements in the campaigns are radiometric ones with field radiometers such as Analytical Spectral Devices FieldSpec3 or TriOS RAMSES. The field radiometers must be regularly calibrated. We, in the paper, introduce the optical laboratory built in KOSC and the relative calibration method for in-situ measurement spectroradiometer. The laboratory is equipped with a 20-inch integrating sphere (USS-2000S, LabSphere) in 98% uniformity, a reference spectrometer (MCPD9800, Photal) covering wavelengths from 360 nm to 1100 nm with 1.6 nm spectral resolution, and an optical table ($3600{\times}1500{\times}800mm^3$) having a flatness of ${\pm}0.1mm$. Under constant temperature and humidity maintainance in the room, the reference spectrometer and the in-situ measurement instrument are checked with the same light source in the same distance. From the test of FieldSpec3, we figured out a slight difference among in-situ instruments in blue band range, and also confirmed the sensor spectral performance was changed about 4.41% during 1 year. These results show that the regular calibrations are needed to maintain the field measurement accuracy and thus GOCI data reliability.

Characterization of Bovine Lymphocyte Antigen DRB3 exon2 Gene of Korean Native Cattle (한우의 BoLA DRB3 exon2 유전자의 특성)

  • Kang, Ho Bum;Ryoo, Seung Heui;Lee, Sang Hoon;Jeon, Byung Soon;Sang, Byung Chan
    • Korean Journal of Agricultural Science
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    • v.25 no.1
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    • pp.79-88
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    • 1998
  • This study was performed in order to apply to effective breeding of Korean native cattle on the molecular genetic level obtained from PCR and nucleotide sequencing analysis of BoLA DRB3 exon2 that has important roles in host immune defence. Genomic DNA used in this study was prepared from the blood of Korean native cattle in Korean Native Cattle Improvement Center of National Livestock Cooperation. The results obtained from this study are summarized as follows: 1. Genomic DNA extracted from the blood of Korean native cattle was subjected to electrophoresis on 1.5% agarose gel. Major band was bigger than 12.2kb, indicating that genomic DNA was well prepared for PCR. Amplified products of 284bp fragments was obtained the amplification of BoLA DRB3 exon2 gene by PCR. 2. Cloning of BoLA DRB3 exon2 of Korean native cattle with pCR2.1 vector was conformed by 300bp fragment from recombinent plasmid that restricted with enzyme digestion of EcoRI. 3. Homology of BoLA DRB3 exon2 alleles of parent was 82.0% between sire's alleles and 90.1% between dam's alleles. 4. In pedigree analysis using BoLA DRB3 exon2 gene, sequencing result of BoLA DRB3 exon2 genes showed inheritance by Mendelian mode through the parents to their offspring. 5. Taking together those experimental results, pedigree was confirmed on the basis of sequencing for the alleles of parents and offspring. This knowledge by the molecular biological approach could be served for the improvement of Korean native cattle.

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Identification of Lettuce Germplasms and Commercial Cultivars Using SSR Markers Developed from EST (EST로부터 개발된 SSR 마커를 이용한 상추 유전자원 및 유통품종의 식별)

  • Hong, Jee-Hwa;Kwon, Yong-Sham;Choi, Keun-Jin;Mishra, Raghvendra Kumar;Kim, Doo Hwan
    • Horticultural Science & Technology
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    • v.31 no.6
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    • pp.772-781
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    • 2013
  • The objective of this study was to develop simple sequence repeat (SSR) markers from expressed sequence tags (EST) of lettuce (Lactuca sativa) and identify 9 germplasms from 3 wild species of lettuce and 61 commercial cultivars using the developed EST-SSR markers. A total of 81,330 lettuce ESTs from NCBI databases were used to search for SSR and 4,229 SSR loci were identified. The highest proportion (59.12%, 2500) was represented by trinucleotide, followed by dinucleotide (29.70%, 1256) and hexanucleotide (6.62%, 280) among SSR repeat motifs. Totally 474 EST-SSR primers were developed from EST and a random set of 267 primers was used to assess the genetic diversity among 9 germplasms and 61 cultivars. Out of 267 primers, 47 EST-SSR markers showed polymorphism between 7 cultivars. Twenty-six EST-SSR markers among 47 EST-SSR markers showed high polymorphism, reproducibility, and band clearance. The relationship between 26 markers genotypes and 70 accessions was analyzed. Totally 127 polymorphic amplified fragments were obtained by 26 EST-SSR markers and two to nine SSR alleles were detected for each locus with an average of 4.88 alleles per locus. Average polymorphism information content was 0.542, ranging from 0.269 to 0.768. Genetic distance of clusters ranged from 0.05 to 0.94 between 70 accessions and dendrogram at a similarity of 0.34 gave 7 main clusters. Analysis of genetic diversity revealed by these 26 EST-SSR markers showed that the 9 germplasms and 61 commercial cultivars were discriminated by marker genotypes. These newly developed EST-SSR markers will be useful for cultivar identification and distinctness, uniformity and stability test of lettuce.

Deterimination of an Optimal Time Point for Analyzing Transcriptional Activity and Analysis of Transcripts of Avian Influenza Virus H9N2 in Cultured Cell (배양세포에서 Semi-quantitative RT-PCR에 의한 조류인플루엔자 H9N2의 전사활성 분석 최적 시기 결정 및 전사체 분석)

  • Na, Gi-Youn;Lee, Young-Min;Byun, Sung-June;Jeon, Ik-Soo;Park, Jong-Hyeon;Cho, In-Soo;Joo, Yi-Seok;Lee, Yun-Jung;Kwon, Jun-Hun;Koo, Yong-Bum
    • Korean Journal of Microbiology
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    • v.45 no.3
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    • pp.286-290
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    • 2009
  • The transcription of mRNA of avian influenza virus is regulated temporally during infection. Therefore, the measurement of transcript level in host cells should be performed before viral release from host cells because errors can occur in the analysis of the transcript levels if the viruses released from the infected cells re-infect cells. In this study, the timing of viral release was determined by measuring the level of viral RNA from viruses released from H9N2-infected chicken fibroblast cell line UMNSAH/DF-1 by semi-quantitative RT-PCR. The viral genomic RNA was isolated together with mouse total RNA which was added to the collected medium as carrier to monitor the viral RNA recovery and to use its GAPDH as an internal control for normalizing reverse transcription reaction as well as PCR reaction. It was found that viral release of H9N2 in the chicken fibroblast cell line UMNSAH/DF-1 took between 16 and 20 h after infection. We measured all 8 viral mRNA levels. Of the 8 transcripts, 7 species of viral mRNAs (each encoding HA, NA, PB1, PB2, NP, M, NS, respectively) except PA mRNA showed robust amplification, indicating these mRNA can be used as targets for amplification to measure transcript levels. These results altogether suggest that the method in this study can be used for screening antiviral materials against viral RNA polymerase as a therapeutic target.

Antioxidative Activity and Component Analysis of Fermented Melissa officinalis Extracts (레몬밤 발효추출물의 항산화 활성과 성분 분석)

  • Yang, Hee-Jung;Kim, Eun-Hee;Park, Jung-Ok;Kim, Jung-Eun;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.35 no.1
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    • pp.47-55
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    • 2009
  • In this study, the antioxidative effects, inhibitory effects on tyrosinase, and component analysis of fermented Melissa officinalis extracts were investigated. The ethyl acetate fraction of fermented extract ($8.38{\mu}g/mL$) showed the most prominent the free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activities ($FSC_{50}$) of extract/fractions of M. officinalis. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of some M. officinalis extracts on ROS generated in $Fe^{3+}$-EDTA/$H_{2}O_{2}$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction of fermented extract ($0.63{\mu}g/mL$) showed the most prominent ROS scavenging activity. The protective effects of extract/fractions of M. officinalis on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The M. officinalis extracts suppressed photohemolysis in a concentration dependent manner ($5\;{\sim}\;75{\mu}g/mL$). The inhibitory effect of M. officinalis extracts on tyrosinase was investigated to assess their whitening efficacy. Inhibitory effects ($IC_{50}$) on tyrosinase of some M. officinalis extracts was 50 % ethanol extract ($365{\mu}g/mL$) < ethyl acetate fraction of fermented extract ($122.43{\mu}g/mL$) < ethylacetate fraction ($94.8{\mu}g/mL$). Fractions of ethyl acetate both from ordinary and fermented M. officinalis extracts showed 2 band in TLC and 2 peak in HPLC (330 nm). In HPLC chromatogram of ethyl acetate fraction, peak 1 (51.64 %) and peak 2 (48.36 %) were identified as caffeic acid and rosmarinic acid in the order of elution time. Also, in HPLC chromatogram of ethyl acetate fraction of fermented extract, peak 1 (4.13 %) and peak 2 (95.87 %) were identified as caffeic acid and rosmarinic acid in the order of elution time. These results indicate that the component and content of ordinary and fermented extracts of M. officinalis are different. And the extract of M. officinalis can be used as an antioxidant.

Theoretical Research for Unmanned Aircraft Electromagnetic Survey: Electromagnetic Field Calculation and Analysis by Arbitrary Shaped Transmitter-Loop (무인 항공 전자탐사 이론 연구: 임의 모양의 송신루프에 의한 전자기장 반응 계산 및 분석)

  • Bang, Minkyu;Oh, Seokmin;Seol, Soon Jee;Lee, Ki Ha;Cho, Seong-Jun
    • Geophysics and Geophysical Exploration
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    • v.21 no.3
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    • pp.150-161
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    • 2018
  • Recently, unmanned aircraft EM (electromagnetic) survey based on ICT (Information and Communication Technology) has been widely utilized because of the efficiency in regional survey. We performed the theoretical study on the unmanned airship EM system developed by KIGAM (Korea Institute of Geoscience and Mineral resources) as part of the practical application of unmanned aircraft EM survey. Since this system has different configurations of transmitting and receiving loops compared to the conventional aircraft EM systems, a new technique is required for the appropriate interpretation of measured responses. Therefore, we proposed a method to calculate the EM field for the arbitrary shaped transmitter and verified its validity through the comparison with analytic solution for circular loop. In addition, to simulate the magnetic responses by three-dimensionally (3D) distributed anomalies, we have adapted our algorithm to 3D frequency-domain EM modeling algorithm based on the edge-FEM (finite element method). Though the analysis on magnetic field responses from a subsurface anomaly, it was found that the response decreases as the depth of the anomaly increases or the flight altitude increases. Also, it was confirmed that the response became smaller as the resistivity of the anomaly increases. However, a nonlinear trend of the out-of-phase component is shown depending on the depth of the anomaly and the used frequency, that makes it difficult to apply simple analysis based on the mapping of the magnitude of the responses and can cause the non-uniqueness problem in calculating the apparent resistivity. Thus, it is a prerequisite to analyze the appropriate frequency band and flight altitude considering the purpose of the survey and the site conditions when conducting a survey using the unmanned aircraft EM system.

Antioxidant Activity and Component Analysis of Fermented Lavandula angustifolia Extracts (라벤더 발효추출물의 항산화 활성과 성분 분석)

  • Park, Soo-Nam;Ahn, You-Jin;Won, Bo-Ryoung;Kang, Myung-Kyu;Kim, Jai-Hyun
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.35 no.2
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    • pp.125-134
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    • 2009
  • In this study, the antioxidative effects, inhibitory effects on tyrosinase, and component of non-fermented and fermented Lavandula angustifolia extracts were investigated. The ethyl acetate fraction of fermented extract (5.95 ${\mu}g/mL$) showed the most prominent the free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of L. angustifolia extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction of fermented extract (1.45 ${\mu}g/mL$) showed the most prominent ROS scavenging activity. The protective effects of extract/fractions of L. angustifolia on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The L. angustifolia extracts suppressed photohemolysis in a concentration dependent manner (1 ${\sim}$ 50 ${\mu}g/mL$). The inhibitory effect of L. angustifolia extracts on tyrosinase was investigated to assess their whitening efficacy. Inhibitory effects ($IC_{50}$) on tyrosinase were determined with ethyl acetate fraction of L. angustifolia extract (144.80 ${\mu}g/mL$) and ethyl acetate fraction of fermented extract (122.40 ${\mu}g/mL$). Fractions of ethyl acetate and fermented extracts showed both 3 band in TLC and 3 peaks, 2 peaks in HPLC (340 nm), respectively. In each chromatography, fractions of ethyl acetate both from non-fermented and fermented L. angusfifolia have rosmarinic acid in common. These results indicate that the component and content of non-fermented and fermented extracts of L. angustifolia are different. Both of the extract of L. angustifolia can be used as an antioxidant.

The Mechanisms of Resistance to TNF in TNF-Sensitive Cancer Cells Transfected with TNF-$\alpha$ Gene Using Retroviral Vector (암세포에서 Retroviral Vector를 이용한 종양괴사인자 유전자 이입후 획득된 종양괴사인자 내성의 기전)

  • Lee, Hyuk-Pyo;Oh, Yeon-Mok;Yoo, Chul-Gyu;Kim, Young-Whan;Shim, Young-Soo;Han, Sung-Koo
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.3
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    • pp.547-558
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    • 1997
  • Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. However, since the efficiency of current techniques of gene transfer is not satisfactory, the majorities of current protocols is aiming the in vitro gene transfer to cancer cells and re-introducing genetically modified cancer cells to hoot. In previous study, it was shown that TNF-sensitive cancer cells transfected with TNF-$\alpha$ cDNA would become highly resistant to TNF. Understanding the mechanisms of TNF-resistance in TNF-$\alpha$ gene transfected cancer cells would be an important step for improving the efficacy of cancer gene therapy as well as for better understandings of tumor biology. This study was designed to evaluate the role of new protective protein synthesis in the acquired resistance to TNF of TNF-$\alpha$ gene transfected cancer cells. Method : We transfected TNF-$\alpha$ c-DNA to WEHI164, a murine fibrosarcoma cell line, using retroviral vector(pLT12SN(TNF)) and confirm the expression of TNF with PCR, ELISA, MIT assay. Then we determined the TNF resistance of TNF gene transfected cells(WEHI164-TNF) and the changes of TNF sensitivities after treatments with actinomycin D(transcription inhibitor) and cycloheximide ( translation inhibitor). Results : WEHI164 which was sensitive to TNF became resistant to TNF after being transfected with TNF-$\alpha$ gene and the resistance to TNF was partially reversed after treatment with actinomycin D, but not with cycloheximide. Conclusion : The acquired resistance to TNF after TNF-$\alpha$ gene transfection may be associated with synthesis of some protective proteins.

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