• Title/Summary/Keyword: synthetic ice

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Simultaneous Analytical Techniques for Determination of 8 Synthetic Food Colors in Foods by HPLC (HPLC를 이용한 식품중 식용타르색소 8종의 동시분석)

  • Park, Sung-Kwan;Lee, Chang-Hee;Park, Jae-Seok;Yoon, Hae-Jung;Kim, So-Hee;Hong, Yeun;Lee, Jong-Ok;Lee, Chul-Won
    • Analytical Science and Technology
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    • v.13 no.3
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    • pp.378-384
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    • 2000
  • This Study has been carried out to develop a method of analysis of 8 permitted synthetic food colors [including Brilliant Blue FCF(B1), Indigocarmine (B2), Fast green FCF(G3), Amaranth (R2), Erythrosine (R3), Allura red (R40), Tartrazine (Y4), Sunset Yellow FCF (Y5)] in Korean foods by HPLC. After adjusting to 0.5% HCl, each of the food colors extracted was eluted by Sep-pak $C_{18}$ cartridge. Eluates were then determined by high performance liquid chromatograph with a UV-VIS detector. Recoveries of the 8 synthetic food colors were found to be 81.2-98.0% for soft drinks, 80.6-96.1% for candy, 79.8-96.3% for chewing gum, 76.5-91.7% for cereals, 79.9-93.8% for ice cream and 78.6-94.7% for jelly, respectively. The detection limits were $0.05-0.1{\mu}g/g$.

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Remote Sensing of Surface Films as a Tool for the Study of Oceanic Dynamic Processes

  • Mitnik, Leonid;Dubina, Vyacheslav;Konstantinov, Oleg;Fischenko, Vitaly;Darkin, Denis
    • Ocean and Polar Research
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    • v.31 no.1
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    • pp.111-119
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    • 2009
  • Biogenic surface films, which are often present in coastal areas, may enhance the signatures of hydrodynamic processes in microwave, optical, and infrared imagery. We analyzed ERS-1/2 Synthetic Aperture Radar (SAR) and Envisat Advanced Synthetic Aperture Radar (ASAR) images taken over the Japan/East Sea (JES). We focused on the appearance of the contrast SAR signatures, particularly the dark features of different scales caused by various oceanic and atmospheric phenomena. Spiral eddies of different scales were detected through surface film patterns both near the coast and in the open regions of the JES in warm and cold seasons. During field experiments carried out at the Pacific Oceanological Institute (POI) Marine Station 'Cape Shults' in Peter the Great Bay, the sea surface roughness characteristics were measured during the day and night using a developed polarization spectrophotometer and various digital cameras and systems of floats. The velocity of natural and artificial slicks was estimated using video and ADCP time series of tracers deployed on the sea surface. The slopes of gravity-capillary wave power spectra varied between .4 and .5. Surface currents in the natural and artificial slicks increased with the distance from the coast, varying between 4 and 40 cm/s. The contrast of biogenic and anthropogenic slicks detected on vertical and horizontal polarization images against the background varied over a wide range. SAR images and ancillary satellite and field data were processed and analyzed using specialized GIS for marine coastal areas.

On the Spatial and Temporal Variability of L-band Polarimetric SAR Observations of Permafrost Environment in Central Yakutia

  • Park, Sang-Eun
    • Korean Journal of Remote Sensing
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    • v.33 no.1
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    • pp.47-60
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    • 2017
  • The permafrost active layer plays an important role in permafrost dynamics. Ecological patterns, processes, and water and ice contents in the active layer are spatially and temporally complex depending on landscape heterogeneity and local-scale variations in hydrological processes. Although there has been emerging interest in the application of optical remote sensing techniques to permafrost environments, optical sensors are significantly limited in accessing information on near surface geo-cryological conditions. The primary objective of this study was to investigate capability of L-band SAR data for monitoring spatio-temporal variability of permafrost ecosystems and underlying soil conditions. This study exploits information from different polarimetric SAR observables in relation to permafrost environmental conditions. Experimental results show that each polarimetric radar observable conveys different information on permafrost environments. In the case of the dual-pol mode, the radar observables consist of two backscattering powers and one correlation coefficient between polarimetric channels. Among them, the dual-pol scattering powers are highly sensitive to freeze/thaw transition and can discriminate grasslands or ponds in thermokarst area from other permafrost ecosystems. However, it is difficult to identify the ground conditions with dual-pol observables. Additional backscattering powers and correlation coefficients obtained from quad-pol mode help understanding seasonal variations ofradar scattering and assessing geo-cryological information on soil layers. In particular, co-pol coherences atHV-basis and circular-basis were found to be very usefultools for mapping and monitoring near surface soil properties.

Development of an Efficient Processor for SIRAL SARIn Mode

  • Lee, Dong-Taek;Jung, Hyung-Sup;Yoon, Geun-Won
    • Korean Journal of Remote Sensing
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    • v.26 no.3
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    • pp.335-346
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    • 2010
  • Recently, ESA (European Space Agency) has launched CryoSAT-2 for polar ice observations. CryoSAT-2 is equipped with a SIRAL (SAR/interferometric radar altimeter), which is a high spatial resolution radar altimeter. Conventional altimeters cannot measure a precise three-dimensional ground position because of the large footprint diameter, while SIRAL altimeter system accomplishes a precise three-dimensional ground positioning by means of interferometric synthetic aperture radar technique. In this study, we developed an efficient SIRAL SARIn mode processing technique to measure a precise three-dimensional ground position. We first simulated SIRAL SARIn RAW data for the ideal target by assuming the flat Earth and linear flight track, and second accessed the precision of three-dimensional geopositioning achieved by the proposed algorithm. The proposed algorithm consists of 1) azimuth processing that determines the squint angle from Doppler centroid, and 2) range processing that estimates the look angle from interferometric phase. In the ideal case, the precisions of look and squint angles achieved by the proposed algorithm were about -2.0 ${\mu}deg$ and 98.0 ${\mu}deg$, respectively, and the three-dimensional geopositioning accuracy was about 1.23 m, -0.02 m, and -0.30 m in X, Y and Z directions, respectively. This means that the SIRAL SARIn mode processing technique enables to measure the three-dimensional ground position with the precision of several meters.

Estimation of Daily Dietary Intake of Food Red Colors - Food Red No.2, No.3 and No. 40 - (식이를 통한 식품첨가물의 섭취량에 관한 연구 - 식용색소적색제2호, 적색제3호 및 적색제40호를 대상으로 -)

  • Park, Sung-Kwan;Lee, Tal-Soo;Park, Seung-Kook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.1
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    • pp.75-80
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    • 2005
  • This study was carried out to measure the amount of daily intake on three synthetic food red colors (Amaranth: R2, Erythrosine: R3, Allura Red: R40) in foods by Korean. Analysis of three synthetic food red colors was conducted by HPLC with the foods including bread, confection, candy, alcoholic beverage, soft drink, ice cream, chocolate, and chewing gum. Recovery rates from the known concentrations of three standard food red colors which were spiked into foods were ranged from 85.1 to 100.4 (%) for each foods. Total Estimated Daily Intake (∑EDI) was from 0 to 1.632 mg/kg bw/day for each food item and from 0.512 to 7.281 mg/person/day for ages (1∼over 65 years old). The data of average food intake for each food item per person per day were obtained from the report of Korean National Nutrition Survey conducted by the Korea Ministry of Health and Welfare in 2001. Total EDI of each red colors per person per day were showed as follows; 0.742 mg/kg bw/day for R2, 0.391 mg/kg bw/day for R3 and 2.018 mg/kg bw/day for R40 as total amount respectively, and the ranges of these values were 0.5∼7.1% of FAO/WHO's Acceptable Daily Intake (ADI) values. Therefore, the amount of daily intake of three synthetic food red colors in Korea was regarded as safe.

Efficient-Use Strategy of ICT based on Integrated Thinking Model (통합사고모형에 기반한 효율적 ICT 활용 전략)

  • Lee, Chul-Hyun;Park, Jong-O;Lee, Tae-Wuk
    • Journal of The Korean Association of Information Education
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    • v.5 no.3
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    • pp.415-431
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    • 2001
  • Recently, the biggest interest in education, education using ICT(Information and Communication Technology) is being emphasized excessively and only the practical side is being embossed on the research about it, so it is causing worry that it is inclined to technical use. In this study, we tried to prepare the strategy for efficient use of ICT in search of theoretical level on use of ICT as an alternative plan for these problems. First, we defined the concept of efficient use of ICT and fixed high thinking of human as basic authority cited for deduction of strategy and analyzed Integrated Thinking Model of Iowa State Dept. of Education. We categorized synthetic thinking for efficient use of ICT through these works. In addition, we classified ICT for efficient use into software area, hardware area, and use skill area, and observed each concepts and interrelationship. And we argued 'Decision Authority of Relation between Thinking Area and ICT Area' to examine relation between synthetic thinking category and each area of ICT, and we established concretization of that, 'Analysis Matrix for Deduction of ICE-EUS'. We tried to guarantee the propriety of deduction process and the clearness of deduction result through this works. Through this process we finally deduct the ICT-EUS(Efficient-Use Strategy of ICT) about learning resources, learning tools, tutee, searching, communication, production and presentation of ICT area. ICT-EUS is expected to provide possibility of being able to enhance the efficiency and effectiveness of achievement of learning goals through cognitive analysis about learning resources, tools and use skills beyond simple use of ICT.

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Estimation of Sea Surface Wind Speed and Direction From RADARSAT Data

  • Kim, Duk-Jin;Wooil-M. Moon
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.485-490
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    • 1999
  • Wind vector information over the ocean is currently obtained using multiple beam scatterometer data. The scatterometers on ERS-1/2 generate wind vector information with a spatial resolution of 50km and accuracies of $\pm$2m/s in wind speed and $\pm$20$^{\circ}$ in wind direction. Synthetic aperture radar (SAR) data over the ocean have the potential of providing wind vector information independent of weather conditions with finer resolution. Finer resolution wind vector information can often be useful particularly in coastal regions where the scatterometer wind information is often corrupted because of the lower resolution system characteristics which is often contaminated by the signal returns from the coastal areas or ice in the case of arctic environments. In this paper we tested CMOD_4 and CMOD_IFR2 algorithms for extracting the wind vector from SAR data. These algorithms require precise estimation of normalized radar cross-section and wind direction from the SAR data and the local incidence angle. The CMOD series algorithms were developed for the C-band, VV-Polarized SAR data, typically for the ERS SAR data. Since RADARSAT operates at the same C-band but with HH-Polarization, the CMOD series algorithms should not be used directly. As a preliminary approach of resolving with this problem, we applied the polarization ratio between the HH and VV polarizations in the wind vectors estimation. Two test areas, one in front of Inchon and several sites around Jeju island were selected and investigated for wind vector estimation. The new results were compared with the wind vectors obtained from CMOD algorithms. The wind vector results agree well with the observed wind speed data. However the estimation of wind direction agree with the observed wind direction only when the wind speed is greater than approximately 3.0m/s.

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Operation of UASB Reactor for Treatment of Dairy Wastewaters (유가공폐수 처리를 위한 UASB 반응조 운전)

  • Bae, Byung-Uk
    • Journal of the Korea Organic Resources Recycling Association
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    • v.3 no.2
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    • pp.37-45
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    • 1995
  • The performance and the operational problems of UASB(Upflow Anaerobic Sludge Blanket) reactor for treatment of dairy wastewaters were investigated. Synthetic milk wastewater was successfully treated up to the loading rate of 3.9kg $COD/m^3.day$, with a specific gas production rate of 1. 23 I/I. day and a COD removal efficiency of over 90%. However, the sludge rising was observed at the loading rate of 2.1kg $COD/m^3.day$, due probably to the formation of scum layer at the surface of settling compartment. The BMP(biochemical methane potential) of raw milk wastewater and ice cream wastewater, measured by using SBT(serum bottle test), were 0.135 and 0.66ml $CH_4/mg\;COD_{added}$, respectively. The sludge activity increased more than 8 times from 0.159g $COD-CH_4/g$ VSS. d during 90 days of operation.

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Seismic properties of Gas Hydrate using Modeling Technique (모델링 기술을 이용한 심해 Gas Hydrate의 탄성파 특성 연구)

  • Shin, Sung-Ryul;Yeo, Eun-Min;Kim, Chan-Su;Kim, Young-Jun;Park, Keun-Pil;Lee, Ho-Young
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.11a
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    • pp.156-157
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    • 2005
  • Gas hydrate is ice-like crystalline lattice, formed at appropriate temperature and pressure, in which gas molecules are trapped. It is worldwide popular interesting subject as a potential energy. In korea, a seismic survey for gas hydrate have performed over the East sea by the KIGAM since 1997. In this paper, we had conducted numerical and physical modeling experiments for seismic properties on gas hydrate with field data which had been acquired over the East sea in 1998. We used a finite difference seismic method with staggered grid for 2-D elastic wave equation to generate synthetic seismograms from multi-channel surface seismic survey, OBC(Ocean Bottom Cable) and VSP(Vertical Seismic Profiling). We developed the seismic physical modeling system which is simulated in the deep sea conditions and acquired the physical model data to the various source-receiver geometry. We carried out seismic complex analysis with the obtained data. In numerical and physical modeling data, we observed the phase reversal phenomenon of reflection wave at interface between the gas hydrate and free gas. In seismic physical modeling, seismic properties of the modeling material agree with the seismic velocity estimated from the travel time of reflection events. We could easily find out AVO(Amplitude Versus Offset) in the reflection strength profile through seismic complex analysis.

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Method Development for the Sample Preparation and Quantitative Analysis of Synthetic Colors in Foods (식품 중 식용타르색소의 시료별 전처리방법 확립 및 함량 분석)

  • Park, Sung-Kwan;Lee, Tal-Su;Park, Seung-Kook
    • Korean Journal of Food Science and Technology
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    • v.36 no.6
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    • pp.893-899
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    • 2004
  • Method for sample preparation and quantitative analysis of 19 permitted and non-permitted synthetic colors in foods was developed based on reversed-phase ion-pairing high performance liquid chromatography. For color extraction of samples, deionized water was added, and pH was appropriately adjusted with 1% ammonia water. Any undissolved matters were extracted with 50% ethanol or 70% methanol. Lipid in snacks was first removed using n-hexane with centrifugation, water was added to extract colors, followed by clean-up and concentration using Sep-Pak $C_{18}$ cartridge. Recovery efficiencies at known concentrations of 19 standard food colors spiked into foods were in 90.3-97.9% range far soft drink, 79.2-101.9% for candy, 84.1-103.4% for jelly, 86.4-100.8% for chewing gum, 83.5-103.4% for ice cream, and 78.5-95.6% for snack.